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2. Which of the following statements is INCORRECT about thixotropic fluids?
(A) Apparent viscosity depends on the time of shearing
(B) Thixotropy is an irreversible process
(C) Thixotropic fluid shows shear thinning behavior
(D) Thixotropic fluids are in general non-Newtonian fluids.
3. A small liquid droplet of radius 1 mm and density 900 kg/m3 is rising up in a column of water. What is the terminal rise velocity of the drop if creeping flow conditions are assumed?(Given: viscosity of water = 1 cp, Gravitational constant g = 10 m/s2 )
(A) m/s (B) m/s (C) m/s (D) m/s
4. Which of the following is NOT RECOMMENDED to increase the collection efficiency of a cyclone separator?
(A) Increase in particle density
(B) Decrease in gas temperature
(C) Increase in particle diameter
(D) Increase in gas flow rate
Statement for Linked Answer – Questions 5 and 6:
In a fluidized bed operation, spherical particles of 1 mm diameter are packed to a height of 1.0 meter. The porosity of this bed is measured to be 0.4. At the minimum fluidization with air the bed height expands to 1.2 meter.
(Given: Particle density = 1200 kg/m3, Gravitational constant g = 10 m/s2 ).
5. The porosity of the bed at minimum fluidization is
(A) 0.4 (B) 0.3 (C) 0.5 (D) 0.6
6. The approximate value of pressure drop in the bed at minimum fluidization will be
(A) 3600 N/m2 (B) 7200 N/m2 (C) 6000 N/m2 (D) 3000 N/m2
7. In a centrifugal filter the inside radius of the filter basket is R2 and radius of the inner surface of liquid is R1. The centrifuge is rotating with an angular speed ?. Which of the following is true about the pressure drop ?P from the centrifugal action?
(A) ?P µ ?1/2 (B) ?P µ (R22 + R12)
(C) ?P µ (R22 – R12) (D) ?P µ ?
8. In a dry crushing operation the mean diameter of the feed and product particles are 100 mm and 1 mm, respectively. The sphericity of the feed and product particles are 0.5 and 1.0, respectively. If the feed particles of 200 mm diameter with the same sphericity are handled at the same feed rate, what will be the percentage increase in power requirement assuming that the product remains the same?
(A) (B) (C) (D)
9. Which of the following is INCORRECT about the boundary layer development over flat infinite plate?
(A) The fluid velocity at solid-liquid interface is zero
(B) The shear rate inside the boundary layer is not zero
(C) The boundary layer thickness increases with distance from the leading edge
(D) The flow in the boundary layer close to the leading edge is turbulent
10. Which of the following velocity field represents an irrotational flow for x, y > 0, x ? y?
(A) V = 2 yi – 2x .j
(B) V = 2 xi – 3y,j
(C) V = xy i – xy j
(D) V = xy i + xy j
11. In a laminar flow between two parallel plates separated by a distance H, the head loss varies
(A) directly as H (B) inversely as H2
(C) directly as H2 (D) inversely as H3
12. Two viscous liquids are to be blended by passing through a pipe. Which of the following would be the most suitable condition for axial mixing?
(A) Creeping flow (B) Low Reynolds number flow
(C) High Reynolds number flow (D) Plug flow
13. A U-tube manometer measures
(A) absolute pressure at a point
(B) local atmospheric pressure at a point
(C) difference in total energy between two points
(D) difference in pressure between two points
14. What will happen to the heat loss if foam insulation, with thermal conductivity 0.09 W/m-K is added to a 5 cm outer diameter pipe carrying hot water? (Heat transfer coefficient on the outer surface = 10 W/m2-K)
(A) Increases (B) Decreases
(C) First increases then decreases (D) Remains constant
15. Biot number (hL/k) is important for which mode of heat transfer?
(A) Natural convection (B) Forced convection
(C) Transient heat conduction (D) Radiation
16. The temperature distribution in a 0.25 m thick wall is given as T (°C) = 250 + bx – cx2,
where x (in meter) is the position of a point with respect to the surface of the wall which is at higher temperature. The thermal conductivity of the wall is 5.95 W/m-°C. What will be the value of b if the surface at x = 0 is insulated?
(A) 0 (B) 1 (C) – 1 (D) 0.5
17. When momentum diffusivity is greater than the thermal diffusivity, the velocity boundary layer
(A) develops faster than the thermal boundary layer
(B) develops slower than the thermal boundary layer
(C) grows together
(D) disappears
18. An aluminium ball of area 0.5 m2 and mass 10 kg is cooled in ambient at 25 °C. When the temperature of the ball is 125 °C, it is found to cool at the rate of 6 °C/min. What will be the surface heat transfer coefficient?
(Given, Cp = 0.5 kJ/kg-°C)
(A) 0.5 W/m2-°C (B) 0.01 W/m2-°C
(C) 0.05 W/m2-°C (D) 0.l W/m2-°C
19. Water at 25 °C enters a pipe with internal diameter 2 cm having a constant wall heat flux of 1 KW/m2. The flow is hydro dynamically and thermally fully developed. What will be the difference between the local wall temperature and the local mean (bulk) temperature? (Thermal conductivity of pipe = 0.4 W/m-°C; Nusselt Number = 5.0)
(A) 5 °C (B) 15 °C (C) 10 °C (D) 50 °C
20. When some liquid nitrogen spills on the floor of a laboratory, the droplets move so briskly that they appear to be dancing before they disappear. This phenomenon
(A) is related to pool boiling (B) is related to film boiling
(C) is related to nucleate boiling (D) has nothing to do with boiling
21. Consider sphere 1 enclosed by sphere 2 as shown in the following figure. The area of sphere 2 is double the area of sphere 1. What are the various view factors (F1I, F12, F21, F22)?
(A) 0, 0.5, 0.5, 1 (B) 0.5, 1, 1, 0.5
(C) 0.5, 0.5, 0, 1 (D) 0, 1, 0.5, 0.5
22. A triple-effect evaporator is concentrating a liquid that has no appreciable elevation in boiling point. The temperature of the steam to the first effect is 110 °C and the boiling point of the solution in the last effect is 50 °C. The ratio of the heat transfer resistance of the first effect to that of the overall heat transfer resistance is 0.2. At what temperature will the liquid boil in the first effect?
(A) 95 °C (B) 98 °C (C) 90 °C (D) 92 °C
23. Gas A is being cracked on a catalyst as per the reaction, A?2B+C in such a way that A diffuses to the cracking surface and B diffuses back, while C is not diffusing. At steady state what will be the ratio of molar flux of A to the total molar flux? | https://www.simplyfreshers.com/drdo-paper-technical-electronics-sep-2010-kolkata/ |
The 2014 SYFLA season opened with our SITC Players’ production of The Tempest. The cast inhabited every corner of Fais Do Do for this production, keeping the audience on their toes. Several of our SITC troupe members now have multiple productions under their belts – they tackled the major roles, and were joined by a dozen new members of our World of Shakespeare introductory class, playing Ariel’s unruly fairies and sprites.
Our LADC veterans wrestled a big Dragon this season. Without a doubt, Richard III makes Macbeth look like a saint. We divided the role of Richard into two parts – the external, charismatic climber and the internal, tormented ruler. As the play progressed, the second Richard took over, culminating in the famous monologue where, in our production, Richard literally argued with himself over his identity and whether he deserved to continue.
We also presented a 1930’s Two Gentlemen of Verona. With tongue planted firmly in cheek, the show opened in a nightclub while a torch singer crooned “What’s cute about a little cutie; it’s her beauty, not brains,” and the entire cast tap danced to “Keep Young and Beautiful.” Establishing those societal expectations gave our young post-feminists (and our audience) insight into why Julia & Proteus might have behaved as they did.
Our youngest Players performed a rollicking Midsummer Night’s Dream. The Runaways navigated the twists and turns of their journey with a skill far beyond their years, and Oberon and Titania introduced their argument with a lyrical dance. The Mechanicals were double-cast as a pack of cranky, misbehaving Fairies, and the audience was delighted by the sense of fun and play they brought to the story. | https://shakespeareyouthfestival.com/2014/08/winter-2014-richard-iii-two-gentlemen-of-verona-midsummer-nights-dream-the-tempest/ |
Bile secretion is a major function of the liver which is frequently impaired in diseases of the liver resulting in the syndrome of cholestasis. The long term objectives of this grant, funded continuously by NIDDK since 1973, have been to characterize the basic transport mechanisms in hepatocytes at the cellular and molecular level that determine the secretion of bile and to define alterations in these mechanisms that result in cholestatic liver disease . In this request for extension of this MERIT award, the specific aims continue much as before. They are Aim 1-A: Mechanisms of Transcriptional Regulation of MRP4/Mrp4 and its role in the adaptive response to cholestasis Aim 1-B: To evaluate the role of basolateral Osta deletion/inhibition in kidney and intestine as a protective effect in cholestasis and hyperlipidemia.
Aim 1 -C: To evaluate the role of MDR3/Mdr2 as therapeutic targets forfenofibrate (FF) and all-trans retinoic acid in human and rat hepatocytes and, if so, by what mechanism.
These aims are a continuation of our work to understand the molecular mechanisms for adaptive regulation of hepatocyte membrane that are important determinants of the adaptive response in cholestatic liver injury - and to devise new therapies based on this information. In particular in Aim 1-A and B we will continue to characterize the transcriptional regulators of the human MRP4 promoter as well as to continue to assess the role that the heteromeric, facilitated bile salt transporter, OSTo-OSTp plays in the adaptive response to cholestasis.
Aim #1 -C determines the molecular mechanisms by which fenofibrate improves cholestatic liver disease and the role of all-trans retinoic acid in this process.
AIM # 2: (previously Aim #3) continues to characterize post-transcriptional mechanisms of regulation of the expression of canalicular ABC transporters by investigating the functional roles of interacting proteins involved in maintaining canalicular apical membrane structural polarity of Mrp2.
AIM #3 : Comparative studies of bile acid transport in marine vertebrates. We will continue to utilize marine animals as comparative models for bile acid transporters in the enterohepatic circulation.
Understanding how the liver adapts to injury resulting from impairment of bile production (known as cholestasis). Bile formation is a vital function &impairment in a variety of cholestasis liver diseases often resulting in progressive cholestasis and liver failure that can result in death or liver transplantation. Understanding the mechanism at the cellular/molecular level, we can design new therapeutic strategies that will augment adaptive responses &retard or reverse the progression of potentially fatal liver disorders. | https://grantome.com/grant/NIH/R37-DK025636-37S1 |
A belief that dance has the power to be world-healing-or at least compassion-awakening-seems to be a common trait among choreographers like Brown who create works that deal with divinity. Their creative process may or may not include personal prayer and meditation, but their works are often active prayers that are intended to affect change.
“What is prayer? I’m not sure I know,” says Liz Lerman, founding artistic director of the Liz Lerman Dance Exchange in Takoma Park, Maryland, who explores questions about God from a Jewish point of view. “But our new piece called Radical Prayer looks at radical action as a form of prayer-at how you create change. I used to think it was through political activism, but now feel I can accomplish more with my art.”
Perhaps dance dissolves barriers between people because it viscerally expresses the human condition and transcends religious differences. Choreographers who explore God in their work may come from specific faith backgrounds, but most say they create works that speak more broadly. Sandra Rivera, a former member of Ballet Hispanico who now performs her own work, often in religious settings, says this is one reason she finds flamenco suited for expressing religious ideas. “It comes from many cultures-European, Sephardic, and Muslim through the Moors,” she says. “I remember performing just after 9/11. I felt all those cultures living in me and coming out to speak, to all cry together.”
Brown’s early days in church are a part of what feed his creativity. But when he began creating Walking Out the Dark (2002), which follows four dancers on a journey from self-doubting isolation, through wrestling with those doubts, to finding the love that allows for community, he found inspiration in other religious places. His visit to a convent in Portugal inspired the dance’s sense of isolation and contemplation. At a funeral ceremony on the Ivory Coast, Brown walked for miles with mourners to a gravesite. As they traveled together, each grieved in his or her own way, some shouting, some crying, some silent. The experience led Brown to give his dancers isolated, very personal phrases while sharing a collective journey.
Ranee Ramaswamy, founder and artistic director of Ragamala, a Minneapolis-based dance company, creates works based in the classical Indian dance form bharatanatyam, which was originally part of Hindu temple rituals. Traditional bharatanatyam uses codified gestures to tell stories, often of gods or goddesses. The form arose thousands of years ago from a single faith, but the message, says Ramaswamy, is much broader. “The dances are very specific, very word-based,” she says. “But the stories they tell are the same ones you hear every day on Oprah.” To illustrate this point, she once set a bharatanatyam-style piece about a jilted lover to a blues song that expressed the same feelings.
Traditional bharatanatyam prayer pieces are solos that focus on the hands and face. “They are emotionally heavy and very difficult to do because the expressions must be just so,” says Ramaswamy. “They are very specific and set, but each dancer must find a way to interpret the stories poetically and believably.”
Kevin Iega Jeff, artistic director of Chicago’s Deeply Rooted Productions, says that dancers these days tend to focus on being physical and technical. “Their depth of physicality is a wonderful thing,” he says, “but there’s not a lot of subtlety, breath, or stillness. For that, they have to get to a place where they can feel. As technique advances, humanity decreases.”
Jeff says movement with a spiritual meaning comes “from the pelvis, the core. It reverberates from there. It generates from the inside and moves out.” He also believes that spiritual connection is created when the dancer has an awareness of the chakra, or point of metaphysical energy, that lies between the eyes. “I can tell when a dancer is moving with that sense,”‘ he says. “There’s a deep, concentrated focus.”
Brown says his dancers must be “physically generous and interested in sharing their whole selves. They can’t want to protect their souls.” When performing Walking Out the Dark, Brown sometimes experiences intense emotions. “There’s a part where I’m playing a brother saying to his sister, ‘I can’t come to you because I’ve got nothing, nothing to give.’ Sometimes I look over at my partner, Diedre Dawkins, onstage as I dance that part and I can’t stop crying.” When that happens, “the performance feels like prayer,” he says. “It’s a deep experience that you can’t control.”
Lerman, who is currently a visiting professor at Hebrew Union College in New York City, has also considered similarities between performing and prayer. She once made a piece that gave members of the clergy speaking parts within the choreography. Just before the curtain, one of them came to her and said, “You know I won’t be performing tonight.” When he saw her panicked look, he added, “Oh, I’ll go out there. But I won’t be acting. When I speak I’ll really be praying.” Lerman quickly assured him that would be fine. “His intent was to pray,” she says. “When I perform, my intent is to bring myself to an undistracted, pure place. Many religious people would call that prayer, too.”
Jamel Gaines is artistic director of Creative Outlet Dance Theatre of Brooklyn, which performs in churches as well as theaters. He says part of the purpose of his dance ministry is to show harsh historical realities like slavery so they won’t be forgotten. And for Rivera, whose flamenco solos often express the suffering of women worldwide, it’s not always necessary to show victory. “By just going deep into the sorrow and struggle,” she says, “you’re already empowering yourself.”
The drive to break barriers that separate people has led some of these choreographers to topple dance world tradition and invite the real world onto the stage. Lerman uses dancers whose ages span six decades. Gaines’ company includes dancers from diverse backgrounds and he embraces each member as a whole person, problems and all. Because Creative Outlet is associated with Saint Paul’s Community Baptist Church in Brooklyn, congregation members get dance training from the company and sometimes join the group. “One person may be late because they’re having an emotional problem,” says Gaines. “Another is homeless and has no place to go after rehearsal. Part of our ministry is to help them and make it possible for them to perform. As a result, they are deeply committed to the work.”
Brown has also melded church and dance by inviting gospel choirs to perform with his company in the theater. When Evidence danced a section of a work in progress called Truth Don Die in Arizona last April, the choir from Phoenix’s Pilgrim Rest Baptist Church sang the song “‘Your Steps Are Ordered.”
That was the first time Brown ever tried bringing a bit of real church to the theater-but he’s long known the power of taking dance to the pews. “Whenever I am in my hometown on a Sunday, I must go to church with my grandfather and I must dance,” says Brown. “In church, the congregation doesn’t feel like an audience, but like part of it-part of the praise.” In Arizona, after hearing the Pilgrim Rest choir at their church, Brown decided that his dancers’ first encounter with them should take place in their sanctuary. “I just wanted the dancers to listen and mark the piece,” he says. “Instead, they danced it full out right away, on the carpet, three times. And it was perfect. Everything was right.”
Janet Weeks is a freelance writer who lives in Brooklyn. | https://www.dancemagazine.com/when-the-spirit-moves-choreographers-who-draw-inspiration-from-prayer/ |
SINGAPORE – They spend every day together as Sophie and her love interest, Sky, in the musical Mamma Mia!.
In fact, Lucy May Barker, 26, and Phillip Ryan, 28, are a couple off stage as well after meeting at the auditions for the musical in 2015. They are now engaged and plan to get married in 2020.
The chemistry and adoration between them is palpable, with each holding the other’s hands and finishing each other’s sentences during an interview with The Straits Times.
“There are plenty of people on this tour who have spent months away from their partners,” says Barker, who is British.
“But we’ve got to enjoy it for what it is now, because we could be doing two different jobs, and trying to see each other in different time zones,” adds Ryan, who is Scottish.
Audiences can see the real life chemistry of the pair on stage at Mamma Mia! which is playing now at the Sands Theatre at Marina Bay Sands until Nov 18. The musical was last in Singapore in 2014.
The brainchild of producer Judy Craymer, Mamma Mia! combines a story of love, family and friendship, all set to the tune of classic hits by Swedish pop group Abba.
Barker’s character, Sophie, is on a quest to find the father she never knew, while her mother Donna (played by Shona White) has to face three men from past romances.
The feel-good musical romp is also one of the longest-running Broadway shows, and was made into a hit movie with the same name starring Amanda Seyfried and Meryl Streep in 2008, and again this year, in the sequel Mamma Mia! Here We Go Again. Next year marks the 20th anniversary of the musical.
In a serendipitous turn, Barker and Ryan also grew up listening to Abba.
Barker remembers listening to the group’s greatest hits compilation, Abba Gold, on her CD Walkman while walking her dog, while Ryan says his father had a jukebox in their home, “where every second record was an Abba one”.
Having been part of the travelling musical for the past three years, the couple will be retiring from the roles in January next year when the musical ends its run in Hong Kong.
“This is my only big musical career-wise, so I’d like to see what else is out there,” adds Ryan.
“In any case, it never leaves you – you hear the first note of a song and immediately you know, ‘that’s Abba!'”.
WHEN: Now showing, until Nov 18. Tuesdays to Fridays, 8pm; Saturdays, 2 and 8pm; Sundays, 1 and 6pm.
« Cut, Ripped, Jacked, or Swole? | http://meandmylifestyleblog.com/entertainment/real-life-couple-star-as-central-love-interests-in-mamma-mia-musical/ |
If you have a question about this talk, please contact Andrew Thomason.
We say that a graph G is saturated with respect to some graph F if G doesn’t contain any copies of F but adding any new edge to G creates some copy of F. The saturation number sat(F,n) is the minimum number of edges an F-saturated graph on n vertices can have. This forms an interesting counterpoint to the Turan number; the saturation number is in many ways less well-behaved. For example, Tuza conjectured that sat(F,n)/n must tend to a limit as n tends to infinity and this is still open. However, Pikhurko disproved a strengthening of Tuza’s conjecture by finding a finite family of graphs, whose saturation number divided by n does not tend to a limit. We will prove a similar result for hypergraphs and discuss some variants.
This talk is part of the Combinatorics Seminar series.
This talk is included in these lists:
Note that ex-directory lists are not shown. | https://www.talks.cam.ac.uk/talk/index/100435 |
As the number of homeless families rise to an eight year high, can Cardiff cope with the soaring demand this Christmas?
Unstable, unsafe just some of the words used to describe their living conditions. For many this Christmas morning there will be no laughter and no cries of happy children racing down the stairs to open presents from under the tree, instead they will traepse their way down to queue outside a filthy, grubby communal toilet.
Homelessness; it’s never planned. Sometimes life just doesn’t go your way. You may suddenly find yourself jobless, unable to pay your rent with nowhere to go and nobody to turn to. Far too many homeless families are in this situation, forced to spend Christmas in B&Bs, hostels or even on a stranger’s sofa.
For many, Christmas underlines an uncertain future. So how are professionals on the frontline coping with the growing demand to try and keep families off the streets this Christmas?
Working with some of the most vulnerable people in society, homeless charities are providing more than just a roof over people’s heads this festive season.
Latest figures released by the housing charity, Shelter suggest that throughout England, Wales and Scotland, 120,000 families will be homeless or living in temporary accommodation this Christmas, raising the figure to an eight year high this year. Among them 12,903 were in emergency accommodation such as B&Bs and hostels.
Shelter blame rising cost, shortage of housing and councils facing greater difficulty to find suitable, sustainable homes for families stuck in temporary accommodation, making it impossible for them to move on with life.
Wales under the microscope
This year more than 1,100 families in Wales will be waking up this Christmas in a place unfit to call their “home.”
The National Statistics for Wales states that the number of households applying for local authorities housing assistance under the Housing Wales Act 2014 show that from April to June 2016, households assessed or threatened with homelessness reached, 2,349. In Cardiff by the end of the quarter, 390 were held in emergency accommodation.
Shortage of social housing means it’s increasingly difficult for people to find a home that suits their needs and budget. Heddyr Gregory, a spokesperson from Shelter Cymru unveils, life can spiral out of control and in a matter of months your home is put at risk.
Homeless charities are more than ever finding it tough to keep up with soaring demand for shelter.
The invisible homeless
They don’t sleep on the streets on a bed of cardboard, instead they are people who have been forced out of their homes, forced to live in sometimes dangerous conditions. The harsh realities of modern day hidden homeless means that their suffering is being forgotten.
Shelter UK spoke to 25 families in emergency B&Bs and hostels and around half had been in that situation for more than six months. Every family lived in a single room, with no space for children to play, exposed to drug abuse and fighting, along with strangers sleeping in the filthy corridors.
“We are constantly trying to break
the cycle of homelessness”
Meet Kimberley: Last year was a Christmas she will want to forget. At 34 weeks pregnant she had the devastating news from her landlord saying they were not going to renew their contract. Kimberley felt shame as they simply had to sit and wait until they had to be evicted.
They contacted Shelter, who coached them through every step of the process. Shelter’s specialist advisers make the difference between a family losing their home and keeping it.
Last Christmas, Kimberley pinned a Christmas tree made out of felt onto their bare wall. This year they will have their own tree in a place they can call home.
Intervention and prevention
“On one morning in September, The Wallich saw 46 people sleeping rough in the city centre,” says Zoe Westerman strategic corporate relationships manager at the homeless charity.
She added, “Many people who experience homelessness have multiple needs such as mental health issues and substance misuse, Cardiff can offer a wide range of services which other areas can’t.”
Intervention and prevention of imminent eviction are their key aims. Wallich support residential projects, from direct access to hostels and emergency night shelters, to providing tenancy support projects.
It’s not just about providing families with a bed. Huggard’s, a homeless charity in the city provide opportunities for homeless people to overcome and tackle their complex problems. Richard Landen, hostel manager says, “We are constantly trying to break the cycle of homelessness.”
They tailor their help to each individual’s needs to deal with a number of problems which may be preventing them from living in permanent accommodation. This may be practical help like CV workshops to build skills and confidence to help put them back in employment.
At Huggard’s hostel centre they have 20 rooms, each have an ensuite and are always full. This Christmas even the day centre floor space is used to provide sleeping space for a further 25 people, according to Richard. “It’s a fairly depressing situation, but there is hope”, says Richard.
We may not see these families sleeping on the streets, yet with nowhere to call home they live in fear of the unknown. Evidently charities work harder than just providing a roof over their heads but it’s tougher to cope with the demand.
It’s a sad fact that, for now many will have to endure washing in a filthy communal bathroom, scramble across a room filled with dirty fold up beds they have to share with their parents and siblings then fall asleep to the sounds of bellowing and crying down a corridor.
For more about the homeless: | https://www.jomec.co.uk/altcardiff/no-logo/in-depth-homeless-at-christmas |
Manufacturing And Construction
The Manufacturing industry is experiencing many threats in advanced supply chains, soaring competition, and the constant demand for innovation in the products. We leverage our clients to innovate and stay ahead in the market in today’s consolidated market. Business owners are growing exponentially with exponential technology modification. Moreover, the industrial IoT has enabled entrepreneurs to make smarter decisions that envision generation manufacturing and real-time contextual data. The future manufacturing industry will focus more on new business models with digital transformation, reinvent core operations, serve compelling consumers.
Aluminum Die Casting Market Size, Share & Trends Analysis, By Type (Pressure Die Casting, Permanent Mold Casting, Sand Casting), By Application (Transportation, Industrial, Building &... | https://marketresearchcommunity.com/manufacturing-and-construction/ |
Nowadays, keeping environment at comfort zone with conventional cooler become expensive, especially in wide and semi outdoor spaces. Evaporative cooler which offer a healthy, non-harmful materials, and low cost can be an alternative to keep environment healthy and comfortable. The objective of this experiment is to determine and compare the performance of direct evaporative cooler embedded with heat pipes and without heat pipes. Heat pipes are placed in the section before cooling pad and work as indirect stage. Evaporator sections of heat pipe are placed before cooling pad and the condenser section are placed in the addition sump. The results show that the saturation efficiency of both system increase along with the increase in inlet temperature and decrease along with the decrease in relative humidity. The saturation efficiency also decreases along with the increase in air velocity. The results also show that the saturation efficiency of modified evaporative cooler using heat pipe is higher than direct evaporative cooler. The addition of heat pipes can increase the saturation efficiency of direct evaporative cooler up to 1.03 without addition more power consumption. | https://www.akademiabaru.com/submit/index.php/arfmts/article/view/2473 |
INTRODUCTION
============
Osteoporosis is characterized by low bone mass with consequent increases in bone fragility and susceptibility to fractures and has become a serious public health concern.\[[@B1]\] An osteoporosis prevalence of 36.4% has been reported in Korean adults \[[@B2]\] and older, and postmenopausal women are particularly affected by the disease.\[[@B1],[@B2]\] The Korean National Health and Nutrition Examination Survey (KNHANES) showed that the prevalence of osteoporosis was four times higher in women than men and it was noticeably increased in postmenopausal women aged over 50 years.\[[@B2]\]
Adequate nutrition, especially sufficient calcium and vitamin D intake, play a major role in the prevention and treatment of osteoporosis.\[[@B3]-[@B5]\] However, the calcium intakes of Korean women were only 55.2% of the dietary reference intakes for Koreans (KDRI).\[[@B6]\] Vitamin D is an essential nutrient for bone health in terms of optimal calcium absorption, but studies on the average intake of vitamin D among Korean are limited.\[[@B7]\] Identifying suitable methods to assess calcium and vitamin D intake has been highlighted. Dietary records, 24-hour recall, and food frequency questionnaires (FFQ) are used for the assessment of all nutrient intakes and take a long time to finish, but there is no tool for only the calcium intake in Korea. Of the methods that can be used for dietary assessment, FFQ appears to be simple, reliable, and quite convenient. The validated simple FFQ called the Calcium Calculator™\[[@B8]\] and an online version\[[@B9]\] are available to assess the calcium intake of western populations, whose major source of calcium is dairy products. However, we previously showed that Korean women consumed only 1/3 of their calcium intake from dairy products, and that vegetables were a very important source of calcium.\[[@B10]\] Dark green vegetables have been shown to be a viable source of dietary calcium,\[[@B11],[@B12]\] although the calcium they contain has low bioavailability compared to the calcium in dairy sources. Nonetheless, large servings of vegetables might allow a total intake of calcium that is equivalent to that which can be achieved by eating dairy products. Thus, the Korean version of the Calcium CalculatorTM needs to be developed and must include a variety of vegetables.
The purpose of the present study was to develop the Korean Calcium Assessment Tool (KCAT), a modified version of the Calcium Calculator™, and then validate the KCAT by comparing it with the FFQ used in KNHANES. The FFQ used in KNHANES has been developed and validated for KNHANES by the Ministry of Health and Welfare.
METHODS
=======
1. Subjects
-----------
This study was conducted according to the guidelines laid out in the Declaration of Helsinki, and all procedures involving human subjects were approved by the institutional review board (IRB) of Chung-Ang University. Written informed consent was obtained from all subjects.
During the summer and fall of 2012, the same numbers of Korean women aged \<50 years and ≥50 years were recruited from the outpatient departments and staff members of 6 medical centers: Asan Medical Center, Chung-Ang University Hospital, Hanyang University Hospital Seoul, Kyunghee University at Gangdong, Samsung Medical Center, Catholic University, and Yeouido ST. Mary\'s Hospital. Women were excluded if they had changed their dietary patterns over the past year or had mental problem, or were pregnant or breast-feeding.
2. Assessment of dietary calcium and vitamin D intake
-----------------------------------------------------
Information on age, height, weight, and use of calcium supplements were obtained through interviews. Subjects were asked to complete two questionnaires, the FFQ used by the KNHANES (2008) and the newly developed questionnaire for calcium intake called KCAT. The dietary intake for the last 12 months was assessed, and full-scale photographs were used to assist in estimating portion sizes such as tablespoons, cups, slices, units, bowls, plates and cans. Nutritional intake was analyzed using CAN-Pro 4.0 (Korean Nutrition Society, Seoul, Korea).
The FFQ used by the KNHANES included 11 food groups consisting of 63 food items, and the frequency of servings was classified into nine categories: never or seldom, once a month, 2-3 times a month, one to two times a week, three to four times a week, five to six times a week, once a day, twice a day, and three or more times a day.\[[@B2]\] The portion size of the food items was classified as follows: small, medium, or large. On the other hand, KCAT was developed based on the Calcium Calculator™ created by registered dietitians working for the BC Dairy Foundation in the 1980s.\[[@B8],[@B9]\] The KCAT included 7 food groups consisting of 24 categories with 45 food items containing calcium and vitamin D, which were consumed frequently by Koreans ([Table 1](#T1){ref-type="table"}). Foods with similar calcium content were put into one category and the average calcium content was used. Frequency of servings was recorded as the number of servings per day, week, or month.
3. Statistical analysis
-----------------------
The differences in the intake of calcium and vitamin D between the two questionnaires were analyzed by *t* tests. Pearson\'s correlation coefficients were obtained from both questionnaires to compare calcium and vitamin D intakes. The Bland-Altman plot was used to compare the two questionnaires for quantifying the calcium and vitamin D intakes, and Cohen\'s Kappa Coefficient was evaluated to verify the agreement between the two questionnaires.\[[@B13]\] Statistical analysis was performed using Med Calc Software (MedCalc version 12.4, Ostend, Belgium) and SPSS version 18.0 for windows (SPSS Inc., Chicago, IL, USA). A *P* value \<0.05 was considered statistically significant.
RESULTS
=======
Two hundred and fifty-six women completed both the FFQ used by the KNHANES and the KCAT, and 128 women were \<50 years old ([Table 2](#T2){ref-type="table"}). Women who were aged ≥50 years were significantly heavier and shorter than women who were aged \<50 years, but there was no significant difference in the consumption of calcium supplements between the women who were aged \<50 years and those who were aged ≥50 years.
Calcium intakes as assessed by the FFQ used in KNHANES and by the KCAT were not significantly different, but vitamin D intake as assessed by the KCAT was significantly greater than that assessed by the FFQ used in the KNHANES ([Table 3](#T3){ref-type="table"}). There were no significant differences in calcium and vitamin D intakes between the women who were aged \<50 years and ≥50 years.
Cohen\'s kappa coefficient of 0.78 indicated that calcium intakes as assessed by the FFQ used in the KNHANES and the KCAT were in substantial agreement ([Table 4](#T4){ref-type="table"}), and no subjects were misclassified. On the other hand, Cohen\'s kappa coefficient of 0.42 indicated that the vitamin D intakes as assessed by the FFQ used in the KNHANES and the KCAT were in moderate agreement, and that 2 subjects were misclassified ([Table 5](#T5){ref-type="table"}). Pearson\'s correlation coefficients also showed that there was a significant positive correlation between the intakes of calcium and vitamin D as assessed by the FFQ used in the KNHANES and the KCAT in all subjects, and in women who were aged \<50 years and ≥50 years ([Fig. 1](#F1){ref-type="fig"}, [2](#F2){ref-type="fig"}). In addition, the Bland-Altman plot demonstrated that there were no significant mean differences of the calcium and vitamin D intakes as assessed by the FFQ used in the KNHANES and the KCAT, with 95% limits of agreement ([Fig. 3](#F3){ref-type="fig"}, [4](#F4){ref-type="fig"}).
DISCUSSION
==========
In the study, calcium intakes as assessed by both the FFQ used by the KNHANES and the KCAT were not significantly different but were significantly and positively correlated, suggesting that the KCAT is a valid tool to assess the calcium intake in Korean women. In the validation study, there was no significant difference in the average calcium intake derived from our new FFQ (KCAT) and the reference method (FFQ used in KNHANES). The Pearson correlation coefficient of 0.98 obtained between the two methods was higher than the range reported in previous studies.\[[@B14]-[@B21]\] The FFQ assessing dietary calcium intake in Asian populations showed lower correlation coefficients: 0.51 in Malaysians,\[[@B14]\] \~0.60 in the Japanese,\[[@B15],[@B16]\] and 0.84 in the Vietnamese.\[[@B17]\] On the other hand, in the FFQ assessment of the calcium intake in the western adult diet, a correlation coefficient of 0.64-0.90 between the FFQ and gold standard methods was found.\[[@B15],[@B19]-[@B21]\] The values from the FFQ assessment of calcium intake in westerners are higher than those of the calcium FFQ previously developed from Asians. Calcium FFQ for Americans and Europeans generally have good correlation coefficients, probably because the amount of calcium intake is higher on average and the ranges are wider than those for Asians, and also because their sources of calcium are simple, with a large dependence on milk and milk products. The sources of calcium in the Korean diet are more varied than for the Western diet, and they include dark green vegetables, seaweed, beans, and seafood. Calcium in dairy products has high bioavailability and thus shows greater absorption in the intestine than calcium from nondairy products, like dark green vegetables, and soybeans, but large servings of vegetables are important sources of calcium, especially for Koreans who do not often drink milk.\[[@B10]\] Although there were no significant differences in the average calcium intake assessed by the two methods, the calcium intake assessed by KCAT was slightly higher than that assessed by the FFQ used in KNHANES. This difference could be due to calcium fortified milk being included in the KCAT, but not in the other questionnaire.
In addition, the extent of misclassification by the two methods was assessed, and Cohen\'s Kappa coefficient of 0.78 indicated that the KCAT was able to correctly classify all subjects into the same quartile of calcium intake, with no subject being grossly misclassified. Gross classification according to the quartiles of intake showed reasonable agreement between the two methods. These results are similar to or better than the results of previous studies, where gross misclassification occurred in 0-4%.\[[@B15],[@B17]\] For epidemiologic purposes, the total potential of a questionnaire to categorize subjects by level of nutrient intake is more important than the capacity to measure group means.\[[@B22]\]
Virtually all of the available techniques have been used previously as reference tools against which the various calcium FFQs have been validated, including modified diet history interviews, 4-day weighed or semi-weighed food records, 3-day, 4-day, 7-day, or 14-day estimated food records, as well as 24-h diet recalls and full-length FFQs.\[[@B20]\] Cade et al.\[[@B23]\] suggested that the FFQ could be used in large-scale epidemiological surveys or in clinical settings as a rapid method for ranking the calcium intake, as well as for discriminating between relatively low and probably insufficient (\<500 mg/day) calcium intakes from relatively high and probably sufficient (\>1,000 mg/day) intakes.
In the present study, we also determined whether the KCAT could be used to assess the vitamin D intake in Korean women. We found that the vitamin D intake as assessed by the KCAT correlated well with that assessed by the FFQ used in the KNHANES, but it was also significantly higher. This may not be surprising since among vitamin D containing foods such as vitamin D fortified milk, different types of mushrooms and fish were not included in the FFQ used in the KNHANES but were added in the KCAT. Therefore, it is possible that the KCAT overestimates the vitamin D intake or the FFQ used in the KNHANES underestimates the vitamin D intake.
In addition, our results showed that Cohen\'s Kappa coefficient for vitamin D was 0.42 and 2 subjects was misclassified by KCAT, and the correlation coefficient was 0.7. Masson et al.\[[@B24]\] suggested that when using correlation coefficients above 0.5, more than 50% of the subjects are correctly classified and less than 10% of the subjects are grossly misclassified, and a kappa value above 0.4 is desirable in epidemiological studies. Thus, although we were unable to validate it, the KCAT could also be a useful tool to assess the vitamin D intake for Korean women.
This study had a few potential weaknesses. First, using the FFQ used in the KNHANES as a reference tool may not be best for validation purposes since the FFQ depends on long-term memory. However, this method is considered the most suitable to get the population means and distribution for subjects with reasonable accuracy, especially when combined with visual aids for estimating portion sizes. Second, compared to the new FFQ, the KCAT was not validated in all 4 seasons, which may be important to do since seasonal variation may occur in calcium and vitamin D intakes. Third, since participants were recruited from a few communities only, selection bias might have been present.
The KCAT we developed has several strengths. First, the KCAT is simple and convenient. It consists of only 24 questions, and it takes about 10-15 minutes to complete. Thus, the KCAT can be used not only in epidemiologic studies, but also in clinical settings. Second, the dietary calcium intake can be assessed with excellent validity and reproducibility. Third, the intake of vitamin D, which is related to bone health, can be also evaluated. In conclusion, this study suggests that the new FFQ, the KCAT, can be a useful tool to assess calcium and vitamin D intakes in Korean women due to its validity and feasibility.
No potential conflict of interest relevant to this article was reported.
{#F1}
{#F2}
{#F3}
{#F4}
######
List of the food items included in the Korean Calcium Assessment Tool
######
General characteristics of women aged \<50 years and aged ≥50 years
Data are expressed as the mean±SD.
^a)^*P*\<0.01, ^b)^*P*\<0.001.
######
Comparison of the calcium and vitamin D intakes assessed by a food frequency questionnaire used by Korean National Health and Nutrition Examination Survey and Korean Calcium Assessment Tool
Values are expressed as the mean ±SD.
^a)^Statistical difference in calcium and vitamin D intakes between women aged \<50 years and women aged ≥50 years using the independent t-test.
^b)^Statistical difference in calcium and vitamin D intakes between KNHANES and KCAT using the independent t-test.
KNHANES, the Korean National Health and Nutrition Examination Survey; KCAT, the Korean Calcium Assessment Tool.
######
Cohen\'s Kappa coefficient for quartiles of calcium intake as assessed by the food frequency questionnaires used by the Korean National Health and Nutrition Examination Survey and the Korean Calcium Assessment Tool
^a)^Cohen\'s kappa coefficient of 0.61-0.80 indicates substantial agreement.\[[@B13]\]
KNHANES, the Korean National Health and Nutrition Examination Survey; KCAT, the Korean Calcium Assessment Tool.
######
Cohen\'s Kappa coefficient for quartiles of vitamin D intake as assessed by the food frequency questionnaire used by the Korean National Health and Nutrition Examination Survey and the Korean Calcium Assessment Tool
^a)^Cohen\'s kappa coefficient of 0.41-0.60 indicates moderate agreement.\[[@B13]\]
| |
Page Patterns are a flexible way to trigger actions when Prospects visit web pages that match a defined pattern. Users could build a Page Pattern to add Prospects into lists, tag Prospects, send alerts to reps, and much more.
Creating a Page Pattern
To create a Page Pattern do the following:
- Navigate to Content > Pages > Page Patterns
- Click the New button
- Assign a name to your Page Pattern
- Choose to match all criteria ("ANDs" all criteria together) or any criteria ("ORs" the criteria together)
- Choose from Page URL or Page Title, select an operator, and enter the relevant text into the field
- Activate the Page Pattern by toggling the switch as shown below:
Triggering Automation from a Page Pattern Match
Page Patterns can be associated with Fulfillment Actions, a lightweight, highly responsive automation template. To trigger actions from a visit and Page Pattern match do the following:
- Hover over the row for your selected Page Pattern
- Click the down arrow and select Actions
- Complete the Fulfillment Action template as needed. | https://leadliaison.atlassian.net/wiki/spaces/LL/pages/18932058/Page+Patterns |
If You Traveled Far Enough Through Space, Would You Return To Your Starting Point?
Could the Universe loop around on itself? And, if so, might an intergalactic journey bring you back to your home planet?
Back when people thought the Earth was flat, it was almost heretical to suggest that traveling in a straight line for a long enough distance would eventually bring you back to your starting point. But it’s true: travel about 40,000 kilometers (or 25,000 miles) in any one direction — over the mountains, oceans and any other terrain you ran across — and return you would to where you began. It makes you wonder if space could be the same way. If you got in a rocket ship and traveled fast enough for long enough, and didn’t ruin things by colliding with a distant star or galaxy, could you eventually return to where you started?
It’s not as crazy as it sounds. We might think that the Universe is infinite, going on forever in all directions, but the evidence we have for the size and shape of the Universe is very much finite. For one, it’s only been 13.8 billion years since the Big Bang, and so we can only see the amount of space that 13.8 billion years of light traveling through the Universe and winding up where we are can illuminate. For another, there are hundreds of billions of galaxies, all appearing younger in the distant past the farther away we look. Is it possible that one (or more) of them is an infant version of the Milky Way we grew up in?
Finally, could it be the case, just as the Earth has two dimensions we can move in on it (north-south and east-west, but not up-and-down), that the Universe might be a higher-dimensional structure like a hypersphere or a hypertorus where the various dimensions are closed and finite, curving back on themselves?
If that were the case, if you could travel in a straight line for long enough, you would wind up right back where you started. If you didn’t age, perhaps you could even wind up seeing the back of your own head just by looking for long enough, as your eyes would eventually encounter the light emitted from your own origin. If the Universe were like this, how would we figure it out?
The key would be to look at the Universe on the largest scales and to look for locations where it appeared to have the same properties in different directions on the sky. A Universe that were finite and recurrent would imply that the same structures would appear over and over again in the Universe.
While most of the Universe would be difficult to identify as recurrent, since the finite speed-of-light means we’d be seeing the same objects at different stages in their evolution (like a younger Milky Way), there are always a slew of objects that would appear at the same stage of evolution at various locations. The large-scale structure of the Universe fails to show any structure like this, but there’s an even better place to look: the cosmic microwave background!
The fluctuations in the Big Bang’s leftover glow have a very particular pattern to them: they follow a bell-curve distribution, slightly larger in magnitude on larger scales than smaller ones, having been slightly processed by a few hundred thousand years of cosmic evolution before we observe them. But, despite the intricacies of that pattern, there’s something else: those fluctuations exhibit a random distribution of that particular pattern.
Many algorithms, generated by both humans and artificial intelligence, have been programmed to look for repetitive, non-random signals or for correlations between the fluctuations on various parts of the sky. If the Universe were finite and closed on itself — if parts of it repeated in other places — the cosmic microwave background would hold the evidence.
We’ve searched exhaustively for it, and that evidence simply isn’t there. But the lack of such a detectable, repeating structure doesn’t necessarily mean that the Universe doesn’t have this type of topology. It only means that if the Universe does repeat, if it is a closed hypersurface, and if we could theoretically re-emerge in the same spot after traveling in a straight line for long enough, it is so on a scale that’s larger than the part we can observe. Given that we’re limited to how far light can travel in 13.8 billion years, there’s plenty of room for this to still be the case.
But there’s a catch.
No matter how technologically advanced you imagine a human will someday be, so long as we’re limited by the speed of light we’ll never be able to find out, even if the Universe is really this way. Thanks to dark energy and the accelerated expansion of the Universe, it’s physically impossible to even reach all the way to the edge of today’s observable Universe; we can only get a third of the way there at maximum. Unless the Universe repeated on a scale that was less than about 15 billion light years in diameter today, we’d have no way to ever return to our original starting point by traveling in a straight line.
However, that doesn’t mean it isn’t possible for the Universe to be closed, finite, and for it to fold in on itself the way a Hypersphere or a Three-Torus does. It just means that the expansion of the Universe — accelerating as it is — forbids us from ever completing a single “circumnavigation” of the Universe and returning to our origin. Because of the combination of:
- the finite age of the Universe,
- the finite speed of light,
- the expansion of the Universe and
- the presence of dark energy,
we may never be able to know whether our Universe is infinite or not, and what its true topology is. We can only see what we have access to, and that doesn’t appear to be enough to be decisive concerning scales larger than what we can observe.
All we can see is the part of the Universe accessible to us, which allows us to place constraints on what its topology is allowed to be. As far as we can tell, it’s flat, non-repeating and possibly (but not necessarily) infinite. Perhaps, as time goes on, and more of the Universe slowly reveals itself to us, or as our curvature measurements get more precise, we’ll discover a departure from what we’ve concluded so far. After all, we’re limited by what we’re capable of observing, but those limits will continue to change as the Universe ages. The possibility of a Universe that’s vastly different from what we’ve concluded thus far might lie just beyond the cosmic horizon.
Ethan Siegel is the author of Beyond the Galaxy and Treknology. You can pre-order his third book, currently in development: the Encyclopaedia Cosmologica. | https://develop.bigthink.com/starts-with-a-bang/if-you-traveled-far-enough-through-space-would-you-return-to-your-starting-point/ |
“I hope the young girls seeing Barbie understand how important scientific careers are to helping the world we live in,” Gilbert continued. Mattel has produced dolls representing different professions, from firefighters to doctors and even astronauts. There are also models depicting athletes, such as British sprinter Dina Asher Smith, or other figures such as civil rights activist Rosa Parks. | https://www.newsnetnebraska.org/covid-astrazeneca-vaccine-scientist-becomes-barbie-video/ |
The utility model discloses a laser light source of a ray casting instrument. The laser light source of the ray casting instrument comprises an outer cylinder; a cylindrical mirror mounting hole is non-eccentrically formed in the outer cylinder; a light exit is formed in the top end face of the outer cylinder; the long axis of the light exit vertically intersects with the axis of the cylindrical mirror mounting hole; the light exit is a waisted hole. A straight line in which the long axis of the light exit is located is perpendicular to the axis of the cylindrical mirror mounting hole. As the light exit is the waisted hole and the straight line in which the long axis of the light exit is located is perpendicular to the axis of the cylindrical mirror mounting hole, laser energy passing through a cylindrical mirror is higher than that of an eccentric design method, and wider light beam sector angle can be formed by virtue of refraction by using the cylindrical mirror. Due to the waisted hole design, the width of the waisted hole is changed so that the width of a laser ray cast can be adjusted to a certain extent. Point light rays are directly emergent from the two ends of the light exit; the central position directly facing the laser light source can be obtained very easily according to the positions of point light spots, and positioning can be realized conveniently. | |
The county seat of and largest city in Santa Cruz County sharing its name, Santa Cruz, California, is located in the San Francisco Bay area of the northern part of the state, about 70 miles south of the city of San Francisco on Monterey Bay's northern edges. The city was estimated to be home to a population of more than 56,000 in 2008, with a median annual household income level around $50,600. Like so many cities, particularly those in California, the Santa Cruz real estate market has taken a hit over the past several years since the onset of the financial crisis and the subsequent world recession. The market saw its inventory soar as the number of foreclosures in Santa Cruz rose, and the oversupply sent prices tumbling down even as many potential buyers were unable to secure financing to buy their much-coveted homes.
The Santa Cruz market has come a long way since the beginning of the recession, and many improvements have been seen this year and in the latter part of 2009. Nonetheless, there are still many fluctuations in the market so buyers and sellers must monitor facts closely.
In June, the most recent month for which statistics are available from the Santa Cruz County Association of Realtors, there were 72 new listings for single-family homes, virtually steady from May, when there were 73, but down year-over-year from 85 in June 2009. Despite a lower number of new listings, total inventory in June was higher than it was a year ago and a month ago, with 235 homes for sale in Santa Cruz on the market. Sales of single-family homes were also down, with only 30 sales in June versus 55 in May and 68 a year ago. Prices also still show signs of suffering; both the average and median prices of homes sold in June were below the figures from the previous month and the previous year. The average price in June was $643,000 while the median sales price was $590,000.
Despite struggling signs in the Santa Cruz market for single-family homes, its other market segment, "common interest developments," showed more signs for optimism. Listings remained constant; in June, there were 18 new listings, compared with 20 in May and 17 in June 2009. Inventory stood at 85, down by three from May but up by 20 year-over-year. There were 12 of these properties sold in June, more than double May's sales of just five, and down only slightly from a year ago, when there were 13 sold. The largest improvement in the common interest developments market was in the average number of days properties spent on the market before selling. Last year, the figure was 120 days, and in May it was 157 days. In June, it was just 47 days. Likewise, both the median and the average price of properties sold has risen month-over-month and year-over-year. The average price in June was $401,600 while the median price was $399,500. | http://www.coastalbay.com/blog/santa-cruz-real-estate-market-stats/ |
Q:
Adding another answer hyperlinked to the question itself
I asked this question here
Best way to part answers from solutions?
And obtained a very good answer. Though I now have a new problem.
I want to type the question, then have one answer linked to the number. And one answer linked to the question itself. (See my MWE in the inked thread for an example. Clicking on the number next to the problem should send you one place, clicking on the equation itself, should send you elsewhere)
Here is an MWE, for my progress so far
\documentclass{article}
\usepackage{answers}
\usepackage{enumitem}
\usepackage{hyperref}
\usepackage{multicol}
\usepackage{changepage}
\usepackage{mathtools}
\newcommand{\dx}{\mathop{}\! \text{d} x}
\setlength{\parindent}{0.0mm}
\hypersetup{colorlinks=true,
linkcolor=blue}
% very useful during de-bugging!
%\usepackage[left]{showlabels}
%\showlabels{hypertarget}
%\showlabels{hyperlink}
% solutions file
\Opensolutionfile{mysolutions}
\Newassociation{mysolution}{mySoln}{mysolutions}
% new environment that sets up hypertargets both in the question
% section, and in the answer section
\newlist{myenum}{enumerate}{3}
\newcounter{question}[section]
\newenvironment{question}%
{%
\refstepcounter{question}%
% hyperlink to solution
\hypertarget{question:{\thequestion}}{}%
\Writetofile{mysolutions}{\protect\hypertarget{soln:\thequestion}{}}%
\begin{myenum}[label=\bfseries\protect\hyperlink{soln:\thequestion}{\thequestion}),ref=\thequestion,itemsep=5pt]
\item%
}%
{%
\end{myenum}}
\newenvironment{IntList}[1]{%
\Opensolutionfile{mysolutions}
\centering
\setlength{\columnsep}{50pt}
\begin{adjustwidth}{-3em}{-2em}\begin{multicols}{#1}}{\end{multicols}\end{adjustwidth}\Closesolutionfile{mysolutions}}
\begin{document}
\begin{IntList}{3}
\begin{question}
$\displaystyle \int\sqrt{4-x}\dx$
\begin{mysolution}
$2+3+4$
\end{mysolution}
\end{question}
\end{IntList}
\section{helo}
$ \int x^3 + 2$
\end{mysolution}
\end{question}
\begin{question}
$\displaystyle \int \sqrt{\frac{1}{x^2+1}}\dx$
\begin{mysolution}
$-\frac{2}{3}(4-x)^{\frac{3}{2}}+C$
\end{mysolution}
\end{question}
\end{IntList}
% close solution file
\Closesolutionfile{mysolutions}
% renew the solution environment so that it hyperlinks back to
% the question
\renewenvironment{mySoln}[1]{%
% add some glue
\vskip .5cm plus 2cm minus 0.1cm%
{\bfseries \hyperlink{question:#1}{#1.}}%
}%
{%
}%
\clearpage
\section{Answers!}
% input the file if it exists
\IfFileExists{mysolutions.tex}{\input{mysolutions.tex}}{}
\end{document}
So I want to add another answer below each question, for an example like below
\begin{myanswer}
To solve this problem one must first...
\end{mysanswer}
\end{question}
\end{IntList}
Where my answer is linked to the whole question and the solution is linked to the number. Prefferably the linked equation should work the same way as the answer does. Eg the hyperref works both ways. Any ideas?
Edit: Here is a more minimal example
\documentclass[10pt,a4paper]{article}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{enumitem}
\usepackage{multicol}
\usepackage{mathtools}
\newenvironment{IntList}[1]{%
\centering
\setlength{\columnsep}{50pt}
\begin{multicols}{#1}\begin{enumerate}[itemsep=5pt]}{\end{enumerate}\end{multicols}}
\usepackage[hidelinks]{hyperref}
\newcommand{\IntExerc}[2]{\item \hyperref[#1]{\mbox{ \( \displaystyle #2 \) }}}
\begin{document}
\begin{IntList}{3}
\IntExerc{R1.1}{\int \frac{x^2+3x}{x^2} \,\mathrm{d}x}
\IntExerc{R1.22}{\int\sin(x)\,\mathrm{d}x}
\IntExerc{R1.2}{\int_0^1 \frac{x}{x^2+1} \,\mathrm{d}x}
\end{IntList}
\newpage
\newpage
\begin{align}
\int \frac{x^2+3x}{x^2} \, \mathrm{d}x & = \int \frac{x^2}{x^2} + \frac{3x}{x^2} \, \mathrm{d}x = \int 1 \mathrm{d}x + 3\int \frac{\mathrm{d}x}{x} = x + 3 \ln|x| + \mathcal{C} \label{R1.1} \\
\int\sin(x)\,\mathrm{d}x & = -\cos(x) + C \label{R1.22} \\
\int\sin(x)\,\mathrm{d}x & = -\cos(x) + C \label{R1.2}
\end{align}
\end{document}
This is closer to the output I want from the answers, package. Note that I have to type the answers seperately, add labels. And have no hyperlinks attached to the numbers.
( I would also prefer to have the syntax below, but I guess this is not possible. )
\begin{Questions}[PartI]
\question
\solution
\answer
\question
\solution
\answer
\end{Questions}
\display{solution}{PartI}
\display{answer}{PartI}
Now, any comments and help would be great.
EDIT:
I made some progress! Is there any way to make
the \long and \short "answers" to be incuded at the beginning? It seems cumbersome to type them
over and over again.
\usepackage{etoolbox}
\newcommand\getcurrentref[1]{%
\ifnumequal{\value{#1}}{0}
{??}
{\the\value{#1}}%
}
\hypersetup{colorlinks=true}
\setlength{\parindent}{0.0mm}
% solutions files
% short solutions
\Opensolutionfile{shortsolutions}
\Newassociation{shortsolution}{shortSoln}{shortsolutions}
\Newassociation{short}{shortSolns}{shortsolutions}
% long solutions
\Opensolutionfile{longsolutions}
\Newassociation{longsolution}{longSoln}{longsolutions}
\Newassociation{longs}{longsSolns}{longsolutions}
% new environment that sets up hypertargets both in the question
% section, and in the answer section
\newlist{myenum}{enumerate}{3}
\newcounter{question}[subsection]
\newenvironment{question}[1]%
{%
\refstepcounter{question}%
% hyperlink to solution
\hypertarget{question:{\thesubsection\thequestion}}{}%
\Writetofile{shortsolutions}{\protect\hypertarget{shortsoln:\thesubsection\thequestion}{}}%
\Writetofile{longsolutions}{\protect\hypertarget{longsoln:\thesubsection\thequestion}{}}%
\begin{myenum}[label=\bfseries\protect\hyperlink{shortsoln:\thesubsection\thequestion}{\thequestion.},ref=\thequestion]
\item%
\hypersetup{linkcolor=black}%
\hyperlink{longsoln:\thesubsection\thequestion}{#1}%
}%
{%
\section{Problems}
\subsection{Questions}
\begin{multicols}{3}
\begin{short}
\vspace*{\baselineskip}
\color{white} hello
\vspace*{-\baselineskip}
\end{short}
\begin{longs}
\vspace*{\baselineskip}
\color{white} hello
\vspace*{-\baselineskip}
\end{longs}
\begin{question}{$\int\sqrt{4-x}\mathrm{d}x$}
\begin{shortsolution}
$-\frac{2}{3}(4-x)^{\frac{3}{2}}+C$
\end{shortsolution}
\begin{longsolution}
In order to do this, we must first make a substitution\ldots
\end{longsolution}
\end{question}
\begin{question}{$\int(2x-1)^{50}\mathrm{d}x$}
\begin{shortsolution}
$\frac{1}{102}(2x-1)^{51}+C$
\end{shortsolution}
\begin{longsolution}
A very long solution| much longer than the shorter solution
\end{longsolution}
\end{question}
\begin{question}{$\int\sqrt[n]{x}\mathrm{d}x$}
\begin{shortsolution}
$\frac{n}{n+1}x^{\frac{1+n}{n}}+C$
\end{shortsolution}
\begin{longsolution}
Even longer!
\end{longsolution}
\end{question}
\end{multicols}
\subsection{Some more questions}
hi
ho
lets go
\end{longsolution}
\end{question}
\end{multicols}
% close solution files
\Closesolutionfile{shortsolutions}
\Closesolutionfile{longsolutions}
\clearpage
\section{SHORT answers}
% renew the SHORT solution environment so that it hyperlinks back to
% the question
\renewenvironment{shortSoln}[1]{%
% add some glue
\vskip .5cm plus 2cm minus 0.1cm%
{\bfseries \hyperlink{question:#1}{#1.}}%
}%
{%
}%
% input the file if it exists
\IfFileExists{shortsolutions.tex}{\input{shortsolutions.tex}}{}
\clearpage
\section{LONG answers}
% renew the LONG solution environment so that it hyperlinks back to
% the question
\renewenvironment{longSoln}[1]{%
% add some glue
\vskip .5cm plus 2cm minus 0.1cm%
{\bfseries \hypersetup{linkcolor=blue}\hyperlink{question:#1}{#1.}}%
}%
{%
}%
% input the file if it exists
\IfFileExists{longsolutions.tex}{\input{longsolutions.tex}}{}
\end{document}
A:
So it sounds like you want both a shortsolution environment and a longsolution environment. Here's a solution that does it- it's very similar to my solution to your previous question, hope it's satisfactory, let me know if not.
I've colour-coded the links such that
red links go to the shortsolutions
blue links go to the longsolutions
% long solutions
\Opensolutionfile{longsolutions}
\Newassociation{longsolution}{longSoln}{longsolutions}
% new environment that sets up hypertargets both in the question
% section, and in the answer section
\newlist{myenum}{enumerate}{3}
\newcounter{question}
\newenvironment{question}[1]%
{%
\refstepcounter{question}%
% hyperlink to solution
\hypertarget{question:{\thequestion}}{}%
\Writetofile{shortsolutions}{\protect\hypertarget{shortsoln:\thequestion}{}}%
\Writetofile{longsolutions}{\protect\hypertarget{longsoln:\thequestion}{}}%
\begin{myenum}[label=\bfseries\protect\hyperlink{shortsoln:\thequestion}{\thequestion},ref=\thequestion]
\item%
\hypersetup{linkcolor=blue}%
\hyperlink{longsoln:\thequestion}{#1}%
}%
{%
\end{myenum}}
\begin{document}
\section{Questions}
\begin{multicols}{3}
}%
{%
}%
}%
{%
}%
Following the question update, and in particular, is it possible to include the answers at the beginning?
Yes, this is possible, but remember that your solution files (shortsolutions.tex and longsolutions.tex) are updated every time you compile. If you input them at the beginning of the document, you'll actually be viewing a previous version of them- that's why it works so well when you include them at the end of your document.
Here's a MWE demonstrating how this works- note that you'll need to compile twice after editing any of the solutions.
\Newassociation{shortsolution}{shortSoln}{shortsolutions}
% long solutions
{%
}%
{%
}%
{%
}%
}%
{%
}%
\clearpage
\Opensolutionfile{shortsolutions}
\Opensolutionfile{longsolutions}
\end{document}
| |
Key Points {#FPar1}
==========
Three research models are described for establishing sport-specific classification criteria for the minimum level of impairment, and sport classes, for athletes with vision impairment (VI).Sports should investigate whether the use of additional measures of visual function (e.g. contrast and motion sensitivity) would improve the evaluation of VI.The test procedures used when evaluating an athlete's vision should represent the habitual conditions experienced in the sport.
Introduction {#Sec1}
============
Para-sports provide tremendous opportunities to enhance the physical, social, and psychological well-being of people with impairment \[[@CR1]--[@CR3]\]. In providing these opportunities, an important goal of para-sport is that the winner of competition should be the best athlete, rather than the athlete with the least impairment. To achieve this goal, sport classes are created so that athletes with impairment are grouped to compete against others who possess a similar level of activity limitation. The process of allocating athletes to a sport class is termed classification. The explicit aim of classification is to minimise the impact of impairment on the outcome of competition \[[@CR4]\].
Historically, classification for para-athletes has been performed on the basis of the medical diagnosis of the athlete's impairment (e.g. level of amputation or spinal cord injury), without necessarily considering the impact of the impairment on performance in that athlete's sport. This has meant that each athlete's class might be the same across different sports, despite what were sometimes very obvious differences in the requirements of those sports. As a result, it has been recognised that classification should take into account the specific impact of impairment on performance in a given sport. For instance, an athlete with an amputated hand will possess a significant activity limitation when rowing, and should therefore qualify to compete in para-rowing; however, the amputation is unlikely to limit performance in long-distance running, therefore the athlete should not qualify to compete in para-running. Similarly, in sports for athletes with vision impairment (VI sports), a mild impairment to the central field of vision could result in a significant activity limitation in sports such as shooting or archery, but not necessarily in other sports such as swimming or running. In that case, an athlete with mild central vision loss should qualify to compete in para-shooting and para-archery, but not para-swimming or para-running. Accordingly, a sport-specific approach is required when evaluating the relationship between impairment and sport performance.
The *IPC Athlete Classification Code* \[[@CR5]\], first published as the *IPC Classification Code* in 2007, formally introduced the requirement for all para-sports to develop their own sport-specific system of classification. Specifically, sports were required to adopt a classification system formed on the basis of evidence which demonstrates the impact of impairment on performance in that sport. To assist with this process, in 2011 the International Paralympic Committee (IPC) endorsed a Position Stand \[[@CR4]\] that articulates guidelines for how an evidence-based system of classification can be developed. However, while publication of the 2011 Position Stand underpinned a move towards sport-specific classification in sports that cater for athletes with physical and intellectual impairments, the progress has been much slower in sports for athletes with VI. Although the 2011 Position Stand was written to be applicable to all para-sports, it was developed largely on the basis of experience in classification for athletes with physical impairment. Some of the unique characteristics of VI, and the unique adaptations made to VI sports, including the use of blindfolds and guides, has led to the need for clarity about how the principles from the 2011 Position Stand would apply to VI sports. Therefore, the aim of this new joint Position Stand is to provide guidance for how evidence-based classification should be achieved in VI sports. This current paper adopts, endorses, and expands on the principles of the 2011 Position Stand, to address pertinent issues that are largely unique for athletes with VI. The paper does so by outlining (i) how evidence-based classification should account for the adaptations commonly used in VI sports; (ii) how the athlete evaluation should be conducted during classification; and (iii) the research approaches that can be adopted to establish an evidence-based system of classification in VI sports.
The Impact of Sport Rules on Vision Impairment (VI) Classification {#Sec2}
==================================================================
Most sports within the Paralympic movement are not identical to their able-bodied equivalent, but instead adopt different sport and equipment rules to better account for the capabilities of people with impairment. For instance, in the regular unadapted form of judo played by those without impairment, athletes start the bout by fighting to obtain the most advantageous grip of their opponent, before continuing to compete with the grip in place. However, in the adapted form of judo played by those with VI, athletes start with the grip already in place, so that the athlete with better vision does not hold a substantial advantage in obtaining a grip on their opponent. A variety of sport adaptations of this type are used within VI sports, and those adaptations hold significant consequences for the way in which research into evidence-based classification should be conducted.
There are two important steps involved in classification for an athlete who wishes to take part in para-sport. In the first step, the athlete must have an eligible impairment that meets the minimum impairment criterion (MIC), defined as "the level of impairment that has an impact on sport performance" \[[@CR6], [@CR7]\]. Crucially, the MIC for para-sports should be the level of impairment that decreases an athlete's level of performance in the unadapted form of the sport. That is, if a judoka's VI impacts their ability to compete when following the rules of the unadapted form of the sport (i.e., when required to obtain a grip on their opponent), then they should be eligible to take part in the para-version of the sport. The second step during classification requires an athlete to be allocated a sport class so he/she competes against others with a similar activity limitation. Because para-athletes will compete against each other in the adapted form of the sport, the sport class should be determined on the basis of the impact of the impairment on performance in the adapted form of the sport. If two judokas with VI have different levels of impairment that provide one with an advantage when obtaining a grip, yet no advantage when the grip is in place, then the two athletes should compete in the same sport class.
The decision to make adaptations to sport rules and equipment in VI sports is the responsibility of the individual sport federations responsible for governing those sports (for a list of those federations, see Tweedy et al. \[[@CR8]\]). Federations generally try to minimise these adaptations so that the sport remains as similar as possible to the sighted version; however, it should now be clear that, when made, these modifications hold significant implications for evidence-based classification. In turn, the outcomes of classification research can lead Federations to consider changes to their technical rules. Below we address two modifications commonly used in VI sport (blindfolds and guides) that have significant implications for how evidence-based classification should be established.
Blindfolds {#Sec3}
----------
Blindfolds (or eyeshades) are used in some VI sports to ensure that all athletes have an equivalent level of impairment during competition (i.e. full blindness). Some VI sports require all athletes to wear a blindfold (e.g. goalball), while other sports require only a subset of athletes to do so (e.g. those with the most severe impairment, as is presently the case for VI swimming).
It has been suggested on occasion that a suitable approach to minimise the impact of impairment on the outcome of competition in VI sport would be to require all athletes to wear a blindfold during competition irrespective of the severity of the athlete's VI. However, there are several reasons why most people in VI sports do not accept this view \[[@CR9]\]. First, a blindfold will add to the existing VI of an athlete who is not completely blind, limiting their ability to capitalise on their remaining vision, a skill that is developed through training. Second, there is concern that when compared with those who are completely blind, those who have some degree of vision but compete with a blindfold might in certain cases perform better during competition because they benefit from having vision away from competition. Indeed, those with some vision may have an advantage not only in their ability to access training but also during training; for instance, when visually modelling their actions on others and when using visual feedback (e.g. video). Conversely, those who are completely blind could, in some cases, have an advantage if competing with a blindfold because they may be better adapted to living and competing when fully blind. Evidently, a consultation process with experts in VI sports revealed that rather than being required to use blindfolds, most VI athletes would prefer to compete without one, even if that meant that they might need to compete in a class against others who have less impairment than they do \[[@CR9]\].
Although the use of blindfolds in VI sports remains a controversial issue, there is general agreement that blindfolds are acceptable in some situations (for a discussion see Ravensbergen et al. \[[@CR9]\]). The decision to use blindfolds within a given sport is at the discretion of the individual sport federation governing that sport, although the decision does hold significant implications for how a system of classification should be developed. Given that the minimum impairment criteria should be established on the basis of performance in the unadapted form of a sport, then the criteria should be established by examining performance without the blindfold in place. However, the nature of the research to be performed to establish the sport classes will depend on whether either some or all athletes are required to wear a blindfold during competition.
If all athletes are required to wear a blindfold during competition, then it can be argued that only one class should be necessary because all athletes will have the same level of VI during competition. Further research is unlikely to be necessary because there is no need to establish the relationship between impairment and performance when all athletes have the same level of impairment. If research was to be conducted with the blindfolds in place, and did find better performance by those who have less impairment, then this would imply that differences away from competition (e.g. advantages during training), or perhaps the development of other skills (e.g. balance), have a direct impact on performance during competition. Typically, these factors should not be accounted for during classification.
If only a subset of athletes is required to use blindfolds during competition, then research for the allocation of sport classes should be performed on the basis of performance when those athletes required to wear a blindfold do have the blindfold in place. This can present a particular challenge for evidence-based classification because it will not be clear what an athlete's level of performance might be like without the blindfold in place. When only some athletes must wear a blindfold, it is typically only those who compete in the class for athletes with the most severe VI who must do so. Conceptually, an athlete should be placed into this class when they (1) would be disadvantaged when competing, without the blindfold, against others with less impairment, and (2) would not have an advantage when competing, either with or without the blindfold, against others with more impairment. Consider, for example, VI swimming, where athletes with the most impairment, who currently compete in class 'S11', must swim with fully blackened goggles (unless they have two prosthetic eyes), while those with less impairment in classes 'S13' and 'S12' do not use blackened goggles. Within class S11, most athletes are blind, but there is also a subset of athletes who have a minimal level of vision. Those athletes typically only have the ability to perceive light, yet must compete blindfolded, presumably at least in part to remove any perceived advantage they might have over others who are fully blind. At present though it remains unclear whether those athletes who can perceive light would possess any advantage if allowed to compete without the blindfold. Research is required in that case to show whether the athletes who have minimal vision would perform better without the blackened goggles. Accordingly, an evidence-based decision can be made about whether those athletes should compete in a different class to those who are fully blind, either in a class against athletes with less impairment, or in a separate class altogether. If so, the sport federation should reconsider their requirement for those athletes to compete blindfolded.
Guides {#Sec4}
------
People with VI frequently experience difficulties in their ability to move safely through their environment. A number of sports such as triathlon and skiing account for this impairment in orientation and mobility \[[@CR10]\] by allowing VI athletes to be accompanied by a guide, whose function is to safely lead the athlete during competition. Whereas blindfolds can generally limit or diminish an athlete's ability to perform, guides help to optimise an athlete's performance.
The choice to allow guides during competition is another rule-related issue that is at the discretion of a sport federation. If a guide is used in the adapted form of the sport, then the minimum impairment criteria should once again be established on the basis of performance without the guide when competing in the unadapted form of the sport, while the determination of sport classes should be done when considering performance with the guide. However, in some sports, the overall performance of an athlete will depend, at least in part, on the individual contribution of the guide, and therefore this ideally needs to be controlled when establishing the relationship between impairment and performance during classification research. For example, in VI para-cycling, athletes compete while riding a tandem bike with their guide, with both the athlete and their guide cycling the pedals. Therefore, the athlete's overall performance will depend not only on their own contribution but also that of the guide. For the purposes of classification research, the contribution of the guide should be controlled or eliminated when establishing the impact of impairment on an athlete's performance, for instance, by standardising the contribution of the guide (e.g. using the same guide for all athletes); limiting the contribution of the guide to one of orientation rather than also contributing to locomotion (unless required for safety); or testing the performance of the athlete without the guide present, using modified equipment (e.g. a stationary bicycle ergometer) while simulating competition.
Procedure for the Evaluation of Vision During Classification {#Sec5}
============================================================
We now turn to consideration of how the principles of sport-specific classification should also apply to the procedures used when evaluating the vision of athletes during classification, and the implications for classification research. Historically, the criteria used for the sport classes in VI sport have been based largely on the medical definitions of low vision and blindness adopted by the World Health Organization \[[@CR11]\]. As a result, the tests performed during classification, and the conditions in which they are tested, have largely been medical. For instance, classification is presently conducted using clinical tests of visual acuity and visual fields, with a minimum level of impairment required on at least one of those tests (≥ 1.0 logMAR or ≤ 20° radius, respectively) for an athlete to be eligible to compete in VI sports. However, the relationship between performance on those tests and sport performance remains largely unclear. Consistent with the principles outlined in the 2011 Position Stand, changes to the way that vision is tested during classification are likely to be required to better capture the way that VI impacts sport performance. Here we address procedural factors for vision testing (e.g. lighting, and testing of the best, or both, eyes) that need to be taken into account to better achieve this aim during athlete evaluation.
Generic Versus Sport-Specific Tests {#Sec6}
-----------------------------------
Vision tests that are suitable for classification should adequately measure a specific impairment type and should be resistant to improvement as a result of training \[[@CR4]\]. If a well-trained athlete was to improve his/her vision test performance as a result of training yet there was no change in the underlying impairment, then the athlete's class would incorrectly change. The test results would make it appear as though the athlete's impairment had decreased, and could place the athlete in a class that required them to compete against others with less impairment. The need for tests of vision to be resistant to training holds important implications for the tests that are most likely to be suitable for the purposes of VI classification.
Colenbrander \[[@CR12]\] makes a distinction between tests of visual function that measure the capacity of the visual system to 'see', and tests of functional vision that assess how a person performs on everyday vision-related tasks. While tests of visual function are those that are typically adopted in medical/clinical settings, tests of functional vision are relevant when evaluating the ability of a person to perform activities of daily living. For example, the test of visual acuity is the most common test of visual function, used to evaluate the ability to read letters on a letter chart at a distance of 4--6 m. However, performance on a test of visual acuity might not necessarily predict how well a person performs when reading a book or driving a car \[[@CR13]\]. Instead, respective tests of functional vision (e.g. reading speed or driving performance) are more likely to capture the impact of impairment on task performance. When applied, for example, to swimming, a test that would evaluate an athlete's ability to visually guide their direction to swim in a straight line may be a suitable sport-specific test of functional vision. However, this test may be less appropriate for classification purposes because a VI athlete's ability to swim in a straight line may improve as a result of training; for instance, some VI athletes have been reported to adapt their stroke to feel for the lane ropes \[[@CR14]\], or even to learn to use the feel of waves reflecting from the ropes to better direct themselves. Subsequently, tests of functional vision that directly evaluate the ability to perform a visually-dependent task are likely to be sensitive to improvements as a result of training, and would therefore unfairly penalise those who have adapted to their impairment.
Whereas most tests of functional vision are highly task-specific and therefore differ according to the task in which performance is being evaluated, tests of visual function are generic tests that are similar irrespective of the task. For VI classification, generic tests are likely to be the most suitable tests of vision, as long as impairment to that visual function is known to have a direct impact on performance in the sport. Research is required to establish the relationship between performance on those tests of visual function and performance in the sport of interest, or in a component of that sport that influences overall performance (for examples, see \[[@CR15]--[@CR22]\]). Consequently, a specific level of impairment in visual function could result in very different conclusions about the functional vision of the athlete, depending on the visual demands of the particular sport.
Generic tests of visual function offer a number of advantages that make them suitable for classification. First and foremost, performance is unlikely to change on tests of visual function as a consequence of training, and should therefore only change if the underlying medical condition causing the impairment has changed. Although tests used for classification should not be chosen on the basis of practical reasons, tests of visual function help to streamline classification because a single test of visual function could be used during classification for a range of different VI sports, and those tests are more likely to be familiar to the clinicians who conduct classification. In some cases, it might still be desirable to use a sport-specific rather than generic test of visual function; for instance, classification could be streamlined if there was to be a single sport-specific test of visual function that could replace multiple individual tests of impairment.
The Incorporation of Additional Tests for VI Classification {#Sec7}
-----------------------------------------------------------
VI is presently classified only on the basis of an athlete's performance on tests of visual acuity and/or visual field, leading to concerns that classification may fail to accurately capture the full impact of VI on sport performance \[[@CR9]\]. This is of particular concern because there is likely to be significant variation in the visual function of VI athletes who might have the same visual acuity, but which is caused by a range of different medical conditions. For instance, there may be significant variation in an athlete\'s ability to perceive contrast, depth, movement, and to see in the presence of bright light, depending on the medical condition causing their impairment. An impairment to any one of those additional measures of visual function could have a significant impact on performance in, for example, alpine skiing, yet those aspects of vision are not presently tested during classification. Instead, the present system would evaluate the vision of athletes as being identical if there is no difference in the extent of the impairment to their visual acuity (or visual field). Moreover, it is entirely possible that other potential athletes are excluded because they perform well on tests of visual acuity and field, yet still have an impairment in other aspects of visual function that decrease their skiing performance. Those athletes would be deemed not eligible (NE) to compete in VI competition. Accordingly, there has been a call from athletes and others in VI sport to consider the inclusion of additional tests of vision during classification \[[@CR9]\].
An evidence-based system of classification is necessarily sport-specific and will therefore most probably lead to the adoption of a unique selection of tests of visual function to account for the particular visual demands of each sport. There is a range of different tests that could be considered for inclusion in classification (e.g. acuity, fields, contrast, colour), and therefore, for any given sport, researchers must first narrow down that candidate list by determining the aspects of visual function that might be related to performance in that sport. Those aspects of vision could be established by (1) a considered breakdown of the subtasks performed within the sport and the nature of the visual information likely to be required to perform those tasks (e.g. Erickson \[[@CR23]\]); (2) determining the types of impairment underrepresented in that sport by comparing the impairments common to athletes who play in that sport with those in the overall VI population; and/or (3) an expert consultation process (e.g. via a Delphi review \[[@CR8], [@CR9]\]) whereby VI athletes and their coaches are asked about the aspects of the sport that athletes find challenging as a result of VI (athletes who acquired their impairment after starting to play the sport can be particularly helpful in this regard).
Once the candidate tests of visual function have been established, research can be performed to provide evidence to demonstrate which of those tests are related to performance. Specifically, if impairment to the visual function is associated with a significant decrease in performance in that sport, then the test should be considered for inclusion in classification. However, for the test to be actually incorporated into the classification procedure, the addition of the new test should improve the ability of the classification system to minimise the impact of impairment on the outcome of competition. That is to say, when the test is included, the outcome of competition should be less related to the level of impairment of the athletes competing than what would be possible if the test were not included. It could be that only a single measure, several measures, or a weighted combination of measures may be required \[[@CR8], [@CR24]\].
Although an evidence-based system could conceivably lead to a different selection of vision tests being adopted for classification in each VI sport, many of the visual functions being tested are likely to be common across the sports. In order to streamline classification, the ideal scenario would be to identify one particular test for each of the visual functions. If each sport were to use a different test of the same function (e.g. contrast sensitivity), then classifiers would be required to become familiar with the range of different tests, or specific classifiers would be required for each sport. In order to deal with this issue, an expert meeting of vision specialists has been convened to recommend the 'ideal' classification test for each of the visual functions most likely to be related to performance in sport. Those performing classification research are encouraged to choose from those tests wherever possible to aid in streamlining classification.[1](#Fn1){ref-type="fn"}
Testing the 'Best' Eye or Both Eyes Together {#Sec8}
--------------------------------------------
Classification has historically been performed on the basis of the vision test results obtained when testing the better performing of the two eyes, although this approach has recently been called into question \[[@CR9]\]. When in competition, in most cases athletes use both eyes simultaneously, with aiming sports such as shooting and archery being two exceptions. Therefore, the level of vision established during classification may fail to accurately capture that used during competition \[[@CR12]\]. When compared with testing the best eye alone, the vision of some athletes may improve if tested with both eyes together (combining the information from the two eyes), while conceivably for some athletes vision could be worse when using two eyes (e.g. in some forms of nystagmus). Therefore, classification should not necessarily rely on the test results for the best eye only, but instead, for some sports, consider the use of both eyes *together*. The choice to use the best or both eyes can be made in one of two ways. The first would rely on a simple evaluation of what the habitual situation is likely to be when competing in that sport. That is, if the majority of athletes would typically use both eyes in that sport, then classification should be performed based on the results obtained when testing both eyes together. Research can then establish the relationship between impairment and performance when vision is tested using both eyes. The second option would be to test vision during research when using both eyes together and using the best eye only (or when using a score combining the test results using each eye individually and both together; see Colenbrander \[[@CR25]\]); the test results that best predict variations in performance would provide an evidence-based decision as to whether to classify on the basis of one or both eyes.
Testing 'Best Corrected' Vision {#Sec9}
-------------------------------
The athlete evaluation performed during classification is always performed with the athlete wearing their best possible optical correction (glasses or contact lenses; e.g. IPC \[[@CR26]\]), even if the athlete does not wear that correction during competition. The requirement for athletes to wear their best optical correction when tested is in place because it establishes the best possible vision of the athlete; if it were not in place, many people with fully correctable short- or long-sightedness could simply remove their glasses/contact lenses and qualify to compete in para-sport. The requirement for best correction during classification does remain somewhat controversial though \[[@CR9]\] because it is not always practical for a VI athlete to wear the correction during competition (e.g. to wear glasses while competing in judo or when swimming). Consequently, some athletes compete with a level of visual function that is markedly worse than that which was measured during classification.
Although athletes must wear their best correction during classification, this may not necessarily be the case when taking part in classification research. A primary goal of classification research is to establish the relationship between vision and performance during competition. Consequently, this relationship should be established on the basis of the athlete's level of vision during competition. That is to say, if the athlete were to compete without any correction in place, then when tested for the purposes of classification research, the athlete should be tested without their correction. Failure to do so may lead to an overestimation of the impact of VI on performance. For instance, take an athlete whose impairment is only mild when corrected, yet is more severe when uncorrected. If the athlete was to compete uncorrected, then the impact on performance may be greater than what it would have been if corrected. However, if the athlete's impairment had been evaluated for research purposes when corrected, then it would appear as though this mild impairment had a stronger impact on performance than it really did. Therefore, research should evaluate the athlete's habitual vision during competition to develop a more accurate understanding of the relationship between impairment and on-field performance.
Ambient Lighting During Classification {#Sec10}
--------------------------------------
Classification for VI sports takes place indoors, often in a clinic or hospital, meaning that the lighting conditions may differ markedly from those experienced during competition. For sports played outdoors, the lighting is typically much brighter during competition, and can vary enormously, when compared to the controlled conditions experienced during classification. Even for sports played indoors, athletes can be required to adapt to large differences in lighting, for instance in swimming pools with large windows, or when bright lights are used for broadcast television. This would not represent a problem if changes in ambient lighting were to impact the vision of all athletes similarly. However, an athlete's ability to adapt to changes in lighting can be impacted by some medical conditions more than others (e.g. Cornelissen et al. \[[@CR27]\]). For example, albinism typically impacts vision in bright lighting, while retinitis pigmentosa and some cataracts can selectively reduce vision in dull conditions. As a result, the test results obtained indoors could be a poor predictor of performance in outdoor conditions and in some indoor scenarios.
The decision whether to account for the impact of lighting on vision during classification should be sport-specific. Some support has been expressed for classification to take place outdoors for athletes who take part in outdoor sports \[[@CR9]\]; however, such an approach is likely to be indefensible because outdoor lighting levels can vary drastically, and therefore the outcome of classification would fluctuate depending on the lighting. This would lead to some athletes being classified in bright conditions, while others when it is dull, and might encourage some athletes to selectively seek opportunities for classification in conditions that suit them, resulting not only in an approach that is inequitable, but one that would ultimately be open to legal challenge. Instead, the best approach is likely to be for all sports to continue to classify indoors, but with modifications to the procedure to account for the impact of lighting on vision. Unfortunately, it is not practical indoors to fully simulate the level of lighting experienced outside. Instead, classification should attempt to account for the ability to adapt to different lighting conditions \[[@CR28]\]. Performance on tests of visual function such as visual acuity and/or contrast sensitivity can be assessed in normal indoor conditions, in addition to when performed in the presence of glare (e.g. using the brightness acuity tester \[[@CR29]\]), and when it is dark (e.g. using low-light transmission lenses \[[@CR30]\]). Moreover, the speed of adaptation and/or recovery can also be tested in sports where athletes may be required to adapt to rapid changes in lighting, for instance when skiing through a forest or accounting for shadows on a playing field.
The Relative Impact of Congenital and Acquired VI {#Sec11}
-------------------------------------------------
Para-athletes often have an impairment not only in their ability to perform during competition, but also sometimes in their ability to benefit from training. Successful training outcomes can rely on: access to facilities, equipment, and coaching; having the available time necessary for training; and on possessing the capability to actually travel to a training venue. Conceivably, those with greater impairment may find it more challenging to take part in training. As outlined in the 2011 Position Stand, classification should not account for the impact of impairment on the ability to train, and should instead focus solely on the impact on performance during competition \[[@CR4]\]. Indeed, an athlete who has maximised their training opportunities should not be penalised by being placed into a class that requires them to compete against others with less impairment but who trains less. Nonetheless, in VI sport, there is some concern that classification should, in some cases, take into account the impact of impairment on training, not to account for the ability of athletes to *access* training, but rather because some athletes have a fundamental impairment in their ability to acquire skill during training \[[@CR9]\]. In particular, the age at which the VI was acquired could impair an athlete's ability to acquire both their basic movement skills and their more advanced sport-specific skill during training.
Vision can play a decisive role in the development of motor skill, therefore a person with any degree of congenital VI could experience considerable difficulty in their ability to acquire fundamental motor skills \[[@CR31]\]. Children learn to model their movements on those of others, with this process of observational learning \[[@CR32]\] providing the cornerstone for much of our early motor development. Similarly, success in many sports requires an athlete to learn novel complex movements (e.g. swimming and judo), therefore the skill development of an athlete is likely to be slower if they cannot learn those movements with the benefit of vision. Consequently, an athlete with congenital VI may possess a fundamental limitation in their ability to acquire some motor skills \[[@CR33]\]. The crucial implication is that an athlete with congenital VI might not be able to compete equitably against other athletes who acquired their VI later in life, even if they possess an identical level of vision when measured using standard tests of visual function. This has led some to call for classification to take into account the age or developmental stage at which the impairment was acquired so that those with congenital impairment can compete more equitably \[[@CR9]\].
Caution is warranted though when assuming that those with congenital impairment are always at a disadvantage because there may be some situations in which there is no disadvantage. For instance, the role of vision may be minimal when learning relatively simple sport-specific movements such as those required for cycling and rowing. In those sports, the age of impairment may have little or no effect on the ability to acquire the movement necessary to perform the skill. There may even be certain cases in which a congenital impairment provides an *advantage*; for instance, a congenital impairment could provide an athlete with the opportunity to acquire more hours of deliberate practice in the VI form of the sport \[[@CR34]\]. Moreover, a congenital VI can sometimes lead to sensory substitution, whereby there are improvements in the responsiveness to other sensory information (e.g. hearing and touch \[[@CR35]\]). Although speculative, this compensation could lead to specific advantages in some scenarios, for example in VI shooting where the sport is adapted so that athletes can use the pitch of a sound to align their gun towards the target. It is possible that those with more acute sensitivity to auditory stimuli could have an advantage in auditory guidance and therefore in overall shooting performance \[[@CR21], [@CR22]\].
Given the view outlined in the 2011 Position Stand that classification should not take into account the impact of impairment on the ability to train \[[@CR4]\], there is considerable uncertainty whether the age at which VI is acquired can or should be accounted for during classification. Moreover, there is some concern that to do so would overcomplicate classification \[[@CR9]\]. This position may change if there was to be clear evidence that the impairment--performance relationship is moderated by the age at which an impairment is acquired. Those conducting classification research are encouraged during their research to collect background information that maps the development of the athlete's impairment alongside their development of skill in the sport, ideally employing a developmental history of practice volume in the sport \[[@CR36], [@CR37]\], along with a survey of the age the impairment was acquired and the rate at which it progressed. As a result, research can establish whether the age of acquisition does influence performance, and can help lead to an evidence-based decision about whether the age of acquisition should be factored into classification for that sport in the future.
Models for VI Classification Research {#Sec12}
=====================================
A variety of approaches can be adopted to establish the relationship between impairment and performance during VI classification research. A truly evidence-based system of classification is likely to require a combination of those approaches. For instance, because of the adaptations used in VI sports, some approaches are more suitable for establishing the minimum impairment criteria, while others are more suitable for determining sport classes. Here we describe what are likely to be the three most important models for classification research, and discuss how each can contribute to the development of evidence-based classification (see Table [1](#Tab1){ref-type="table"} for an overview).Table 1Outline of three research models that can be used for VI classification researchResearch modelSuitability for the development of:Advantages (+)/disadvantages (−)Minimum impairment criteriaSport-class criteriaTests to be used during classificationImpairment--performance relationship in VI athletes (correlation model)\~\
The existing MIC may limit the ability to find skilled individuals with less severe impairments✔\
Can determine the impact of the complete range of VI on performance in the adapted form of the sport✔\
Can determine which tests are related to performance and therefore are suitable for classification+ Can test participants with VI (i.e., real medical conditions)\
− The current classification system affects the characteristics of the participants\
− Other factors (e.g. training volume, adaptation, talent) also influence performance and should be accounted forSimulation of vision impairment in skilled fully-sighted athletes (simulation model)✔\
A range of VI severities both below and above the current MIC can be simulated to determine the least severe impairment that starts to impact performance\~\
Sport-class criteria should be set based on the impact of the impairment on performance in the adapted form of the sport✔\
Can determine whether certain aspects of visual function impact performance. This can be used to decide which aspects of visual function to assess during classification+ Can measure the direct effect of impairment on performance, without the effect of long-term adaptation through training\
+ Possible to test outside the range of impairment severities currently eligible\
− Not all impairments can be simulated\
− Not all VI sports have sighted equivalentsEstablishing the visual information relied on by skilled fully-sighted athletes (component-analysis model)✔\
The visual information relied on by skilled athletes could be translated into the VI severity that limits the ability to detect this information\~\
Sport-class criteria should be set based on the impact of the impairment on performance in the adapted form of the sport✔\
New sport-specific tests can be designed that assess whether the athlete can detect the visual information that skilled athletes rely on+ No bias from other (indirect) effects of vision impairment confounding the impairment--performance relationship\
− Not all VI sports have sighted equivalents\
− The visual information used by able-sighted athletes might not match that used by those with VI*VI* vision impairment, *MIC* minimum impairment criterion
Establishing the Impairment--Performance Relationship in Athletes with VI {#Sec13}
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The impairment--performance relationship can be established by measuring the vision of athletes who already participate in para-sport, and correlating the outcomes with measures of the performance of those athletes. Therefore, two key decisions need to be made using this 'correlation' approach: (1) which aspects of visual function should be measured (see Sect. [3.2](#Sec7){ref-type="sec"}); and (2) how best to measure performance in that sport. The evaluation of sport performance could involve measuring overall performance, particularly in sports where performance is measured objectively (e.g. race-time in swimming or throw-distance in javelin). Otherwise, measures could evaluate important determinants of performance when the measurement of overall performance is more complex (e.g. the ability to kick towards a target in football or to intercept a ball in goalball). It is wise to consult experts in the sport to establish the aspects of performance likely to be impacted by VI, and to determine how they are best measured. Performance analysts who scrutinise and measure performance can also be particularly useful in providing advice.
Having measured the visual function and performance of a sufficiently large group of athletes, the outcomes can be correlated and subsequently analysed to examine the nature of the impairment--performance relationship. The three main objectives here are to identify (1) those aspects of vision that best predict sport performance; (2) the most appropriate number of sport classes; and (3) the most appropriate sport-class boundaries. To address the first objective, traditional statistical techniques such as a correlation or multiple linear regression would be appropriate. However, for the purpose of determining the most appropriate number of classes, as well as the criteria for separating those classes, a number of contemporary approaches, such as cluster or decision-tree analyses, are more likely to be suitable (for more detail, see Tweedy et al. \[[@CR8]\]). These approaches can help to determine the measure of visual function, or most likely the combination of measures, that should be used to allocate a sport class during evidence-based classification.
Because this correlation approach assesses athletes who already compete in VI sport, it will most likely involve an examination of performance in the adapted rather than unadapted form of the sport. This makes the approach very useful when establishing the number of sport classes and the borders between them, but may be less suitable for establishing the minimum impairment criteria. However, there are still some scenarios in which this approach is suitable for establishing the MIC; in particular, (i) when the VI form of the sport is identical to the unadapted version; or (ii) when data for sport performance can be collected for those VI athletes competing in the unadapted rather than adapted form of the sport (e.g. by a specially convened competition for the purposes of research).
The principal advantage of this research design is that it can examine the impairment--performance relationship in athletes with impairment when competing in VI sports. Instead of attempting to make inferences on the basis of findings for athletes who do not have impairment, it tests athletes who have a variety of conditions that can impact all aspects of visual function. This provides a holistic impression of how impairments truly influence performance. However, this approach does have its drawbacks. Classification research should evaluate the impact of impairment on performance during competition \[[@CR4]\]. Yet, the relationship between impairment and performance established when using this approach is likely to be influenced by other aspects of an athlete's life that might indirectly influence performance, but are not easy to standardise in a population of VI athletes (e.g. age of impairment, volume and quality of training). In an attempt to overcome this limitation, additional athlete information should be gathered during research (see Sect. [3.6](#Sec11){ref-type="sec"}) to either include only those athletes who meet certain criteria or to control for those additional variables.
An important issue to consider when applying this model is that the present classification system will directly influence the characteristics of the athletes who participate in the research. First, people whose level of impairment is less than that required to meet the prevailing MIC may need to be recruited from the able-sighted equivalent of the sport. However, those individuals may be less likely to be actively competing if their impairment does decrease performance in the unadapted form of the sport. Moreover, they might not be accustomed to some of the adaptations, such as blindfolds and guides, that might be used in the adapted form of the sport. Second, there may be an underrepresentation of people with impairment who qualify for inclusion in the para-version of the sport but whose impairment under the existing classification system places them at a significant disadvantage when compared with others with less impairment within their sport class. Because of this disadvantage, those people may be less likely to be actively competing because, for example, they are not able to meet qualification standards to compete, or they decide to leave the sport. Coaches and administrators within the sports can be very useful in identifying athletes who fit those criteria. If those athletes are found at a local or regional rather than international level, the quantity and/or quality of their training experience may need to be taken into account. Ideally, improvements to a classification system should encourage wider participation and lead to a more representative sample of athletes with impairment taking part in the sport. It is therefore necessary to re-evaluate from time-to-time the impairment--performance relationship found for any newly developed classification system.
Simulation of VI in Skilled Fully-Sighted Athletes {#Sec14}
--------------------------------------------------
The relationship between vision and sport performance can be established by simulating VI in fully-sighted athletes and measuring changes in their sport performance. A number of different aspects of visual function can be manipulated in sighted athletes; for instance, changes in visual acuity, contrast sensitivity, and, in some cases, visual field. These manipulations can be achieved through the use of glasses (e.g. Applegate and Applegate \[[@CR20]\], and Bulson et al. \[[@CR18], [@CR19]\]), contact lenses (e.g. Mann et al. \[[@CR15], [@CR16]\]), or by computer-based simulations, including gaze-contingent displays \[[@CR38], [@CR39]\]. However, it remains challenging, or indeed impossible, to manipulate some other types of visual function (e.g. eye movement disorders).
The simulation approach is most suitable for examining performance in the unadapted form of a sport because fully-sighted athletes would be untrained in the adapted format. As a result, the simulation approach holds promise for establishing the minimum impairment criteria, and may be less useful for establishing sport classes, again unless there are no or minimal differences between the unadapted and adapted forms of the sport. When simulating impairment, the skill level of the able-sighted athletes can be chosen so that it matches that of the VI athletes (e.g. matching race times in swimming) to maximise the relevance of the findings to the VI population.
A particular advantage of the simulation approach is that the impairment--performance relationship can be evaluated while controlling for the amount of time that an athlete has had available to adapt to their impairment. When using the *correlation* approach to test para-athletes, it is not always easy to differentiate whether the better-performing athletes are superior because they have less impairment, or rather because they have had more and/or better-quality practice, and are therefore more adapted to their impairment than less-trained athletes. Therefore, a research approach is desirable that can establish the 'raw' impact of the impairment on performance (i.e. while controlling for adaptation). Note though that when establishing the MIC using the simulation approach, it is important that participants without impairment have had at least some time to adapt to the newly imposed impairment. Existing studies that simulate impairment generally provide athletes with 5--15 min to familiarise themselves with any acute effects of the simulated impairment before testing performance \[[@CR15], [@CR16]\]. Given that a longer period of adaptation is likely to provide athletes with more time to develop strategies to adapt to or overcome the newly imposed activity limitation, then it stands to reason that insufficiently short adaptation times will result in an MIC that requires less impairment than that which might genuinely limit performance over the long-term. That is, an insufficiently short period of adaptation would overestimate the impact of VI on performance, ultimately leading to the inclusion of athletes whose impairment results in only a transient impact on sport performance. A longer period of adaptation would help to overcome this concern, and is desirable for setting an MIC that truly reflects the long-term impact of impairment on performance.
Of course there are limitations to the practicality of the simulation approach. First, some sports might have been created specifically for VI athletes and would therefore not have a sighted equivalent (e.g. goalball). In those cases, it would be challenging to find able-sighted athletes who are skilled in the sport. One possible solution is to evaluate the impact of simulated impairment on performance in a sporting task that is very close to that performed in the VI sport. For example, to test changes in performance in goalball (where competitors attempt to roll a ball into their opponents' goal), the interceptive ability of skilled team handball players could be tested as a representative task. A second potential limitation is that athletes who do not have VI have learned to play the sport with the benefit of vision, and it could be that some elements of their performance are so well-learned that their skills are more 'automatic' and rely on different sources of information to that of lesser-skilled athletes \[[@CR40], [@CR41]\] or athletes with VI. Third, it is not possible to simulate an impairment to all the types of visual function that may be relevant to sport performance. Finally, some VI athletes prefer that classification rules should be created on the basis of the performance of athletes who have VI, rather than on the performance of those who do not \[[@CR9]\]. In particular, there is apprehension that simulations in athletes without VI fail to capture the overall impact of the impairment on the athlete's ability to train and to acquire fundamental and sport-specific motor skills. Moreover, caution is of course required when temporarily impairing the vision of these athletes, i.e. test procedures must meet the requirements of the local Ethics Committee; athletes should be prepared for the physical and psychological reactions they may experience during testing; and an appropriate debrief is advised to avoid athletes being left with a negative perception about what it is like to live with VI.
Establishing the Visual Information Relied on by Skilled Able-Sighted Athletes {#Sec15}
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This final component-analysis approach seeks to identify the visual information that skilled able-sighted athletes rely on for best performance in a given sport, and then determines the level of vision necessary to use that information. This approach is necessarily sport-specific because it requires a considered analysis of the performance-determining components of each sport, and what might be the visual information relied on when performing those tasks. Subsequently, the visual information can be manipulated in an attempt to demonstrate if and when it would be used to facilitate performance. For instance, the turn is a crucial component of most swimming races and it is likely that swimmers rely on the position of the 'T' on the bottom of the pool to initiate their turn. By examining changes in the turn in response to manipulations in the position of the 'T', it is possible to show when in the swim that information is used, and therefore the quality of vision that would be required to see that information \[[@CR42]\] (for examples in long-jump, see also Bradshaw et al. \[[@CR43], [@CR44]\] and Panteli et al. \[[@CR45]\]). Once the visual information relied on by skilled fully-sighted athletes is known, the level of vision required to use that information can be established, and thereby the level of VI likely to limit performance.
An advantage of this model is that it can lead to the design of sport-specific tests of visual function that hold promise as tests of classification. These tests can simulate the demands required during competition and could eliminate the need for separate tests that individually evaluate different aspects of visual function. For example in swimming, it could be that a test that discriminates whether an athlete is able to identify the direction of a 'T' similar to that seen in the pool could replace the need for individual tests of acuity, contrast, and colour. A benefit of this type of sport-specific testing is that it may require fewer tests for classification, although this does need to be weighed against the desire for as few classification tests across sports as is possible and the need to ensure that test performance does not improve in response to training in the sport \[[@CR4]\].
Because this approach considers performance in the unadapted format of the sport, it too holds many of the advantages and drawbacks seen in the previous section for the simulation approach, i.e. it is likely to be most beneficial when establishing the MIC; it does offer the benefit of being able to reduce bias from other factors that indirectly influence performance (e.g. training volume); and it does rely on the assumption that the visual information relied on by VI athletes would match that relied on by athletes without VI.
Conclusions {#Sec16}
===========
The vision of the IPC is to "enable para-athletes to achieve sporting excellence and inspire and excite the world" \[[@CR46]\]. An appropriate system of classification is a significant requirement for the legitimacy of para-sport, and an evidence-based form of classification will help to ensure legitimacy. For athletes with VI, the progress towards evidence-based classification has, to date, been slow. The aim of this joint Position Stand is to provide guidance for how evidence-based classification research should be conducted in VI sports. The differentiation between the adapted and unadapted form of a sport holds significant implications for how evidence-based standards are developed for both the minimum impairment criteria and for the design of sport classes. Moreover, the outcomes of classification research may inform recommendations for the design of sport rules; for instance, the need to reconsider which athletes should use blindfolds during competition. The appropriateness of a sport-specific approach to classification also extends to the conditions in which the athlete evaluation takes place, in particular ensuring that appropriate sport-specific decisions are made about the addition of new tests and the lighting used when performing those tests. Finally, there is no single approach to take when performing research to establish an evidence-based system of classification. A robust system is likely to require a combination of approaches.
There are a number of future challenges that need to be overcome to meet the needs of a legitimate system of classification for athletes with VI. New tests of visual function are required to better account for the impact of VI on sport performance, with those tests needing to be suitable for people with VI and to be representative of aspects of visual function that influence sport performance. An additional challenge is to establish whether a single aspect of vision is capable of describing the impact of impairment on sport performance, or rather whether a particular combination of visual functions should be used. The relationship between impairment and performance is likely to be confounded by other factors such as practice volume and age, therefore these factors should also be measured and controlled wherever possible. When these particular challenges are met and new systems of classification are developed, a key task will be to ensure that appropriate athlete education is in place during implementation. VI athletes are very accustomed to their present system and some may be resistant to change, particularly those who benefit from the current system. Education is required to ensure that all athletes are aware of the purpose of sport-specific classification and the long-term benefits to all athletes. Even the best evidence-based system of classification will not be successful if it is not accepted by the athletes for whom the new system is designed to help.
At the time of writing, the details of these tests that were chosen by the expert panel were not yet published. For further information, please contact the corresponding author.
Funding
=======
This project has been carried out with the support of the International Paralympic Committee.
The authors thank Peter van de Vliet, Anne Hart, Jane Blaine, Peter Allen, and Richard Rawson for their comments on earlier versions of this Position Stand.
Conflicts of Interest
=====================
David Mann receives research funding from the International Paralympic Committee, International Blind Sports Federation, Agitos Foundation, Netherlands Olympic Committee (NOC\*NSF), and the Royal Dutch Football Association (KNVB). Rianne Ravensbergen receives research funding from the Agitos Foundation.
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The literature regarding the effectiveness of CST for individuals with dementia will be critically evaluated.
Learning outcomes
After completing the module, you will know:
- How CST was evaluated,
- Which are the main results of CST evaluation.
Introduction
Several studies have been conducted to evaluate the effectiveness and the usefulness of CST internationally. The literature search showed that more than 120 papers have been written, concerning CST evaluation. Some of these surveys were conducted in UK, Hong Kong, Japan, Tanzania and Portugal. Below the common results among these surveys are presented [1,2].
3.5.1 Cognitive improvement
Based on various systematic reviews on CST, it was found an indication of improved cognition. The commonly used tools, Mini Mental State Examination (MMSE) and the Alzheimer’s Disease Assessment Scale-Cognition (ADAS-Cog), ask a number of questions to ascertain cognitive status of people with dementia. More precisely, these tests primarily investigate memory and orientation, but also language and visual/spatial abilities before and after the CST treatment. The systemic literature review on CST, shows a significant positive impact in cognitive functioning and more precisely in memory, orientation and comprehension of syntax [3,4].
3.5.2 Quality of life
A person’s well-being is considered as a key issue in many aspects of dementia care. Besides the significant improvement in cognitive function, CST intervention offers to individuals with dementia, an enhancement in the quality of their lives (QoL). More specifically, 201 people with dementia living in residential homes or attending day centres were assessed using the Quality of Life-Alzheimer’s Disease scale (QOL-AD) measuring the level of cognition, mood, communication, and dependency to the carer. The impressive results showed that the improvement of QoL had a significant positive correlation with lower levels of dependency and depression, as well as with greater willingness to engage in conversation and communication [4,5].
3.5.3 Cost-effectiveness
Cost-effectiveness analyses for the CST trials were conducted by researchers at the London School of Economics and Political Science (LSE). These studies found that CST is more cost-effective than usual care, especially when looking at benefits in cognition and quality of life .
Synopsis
Key points:
- CST evaluation showed changes and more specifically an improvement in thinking skills, in the quality of patients’ daily life, and offers value for money.
1. List of references
- Toh, M., H., Ghazali, E., S., Subramaniam, P. (2016). The acceptability and usefulness of CST for older adults with dementia: A narrative review. https://www.hindawi.com/journals/ijad/2016/5131570/
- Quayhagen, M., P., Quayhagen, M., Corbeil, R., R. et al. (2000). Coping with dementia: evaluation of four nonpharmacologic interventions. International Psychogeriatrics, vol. 12, no. 2, pp. 249–265. | https://dcare.training/topic/3-5-evaluation-of-cst/ |
Fifty mL refers to 50 milliliters in the metric system of measurement, which is equivalent to approximately 1 2/3 fluid ounces using the U.S. customary system of measurement. In recipes, 50 milliliters equals 1/4 cup.
www.reference.com/world-view/much-50-ml-d88a8fdd6625a030
Five hundred ml, or milliliters, is the same volume as a cube 7.937 centimeters on a side. This is approximately the same volume as two small square milk containers.
www.reference.com/article/much-500-ml-7cc3f01fef859044
MLS referees are paid a set fee per game based on their level of experience. Each of the four experience levels are determined by the total number of matches a referee has officiated.
www.reference.com/article/much-mls-referees-make-57fb89746a09556d
150 milliliters (abbreviated mL) is equal to 0.634 cups. This amount is approximately equivalent to 5.072 ounces. A single cup contains 8 ounces or 236.59 milliliters.
www.reference.com/world-view/150-ml-cups-d8a3f500297349ac
The cup, in United States customary units of measurement, holds 8 U.S. fluid ounces. If the U.S. fluid cup is equivalent to 8 fluid ounces, 2/3 of 8 fluid ounces is 5.28 U.S. fluid ounces. A cup in the British imperial s...
www.reference.com/world-view/2-3-cup-ounces-10642f83d7c42d3e
When converting milliliters to ounces, 750 ml is the equivalent to roughly 25.4 fluid ounces. Milliliters are part of the metric system, while ounces are part of the US and imperial systems of measurements.
www.reference.com/science/many-ounces-750-ml-135a936f45968b75
A measurement of 50 milliliters is equivalent to 1.6907 U.S. fluid ounces. U.S. fluid ounces is slightly different from imperial ounces, with 1 U.S. fluid ounce measuring 29.5735295625 milliliters in the International Sy... | https://www.reference.com/web?q=how+much+is+50+ml&qo=relatedSearchBing&o=600605&l=dir&sga=1 |
Selected books owned by Loyola are included in the Books section of this guide. To find an item in Loyola's collection which is not on this list, please use Loyola's online catalog. Some suggested subject headings you can search and/or browse:
Legal Assistants--United States.
Legal Assistants--United States--Handbooks, manuals, etc.
Legal Research--United States
In the alternative, you can browse the shelves in the Law Library. Generally, books aimed at paralegals are located on our 5th floor, at call numbers KF320. Books on particular legal topics, although written specifically for paralegals, are usually shelved with other books on those topics. (For example, Basic Administrative Law for Paralegals is shelved with other books on administrative law.)
To locate books in libraries outside the Loyola University Chicago System, use the WorldCat database (valid Loyola ID and password required).
Loyola's online library catalog contains records for all of the books in the Law Library and the University Libraries. A few highlighted books are listed below.
To see longer lists of selected books, in three categories - Legal Research and Writing, Paralegal Specific Titles, and Select Legal Topics - scroll over the red Books tab, above, and choose one of the categories that appear below it. | https://lawlibguides.luc.edu/c.php?g=610774&p=4239670 |
With an architecturally pleasing exterior, internally the house delights with its unique and characterful rooms. The Manor is able to accommodate 22 guests comfortably, making it an ideal venue for those special family birthdays, anniversaries or celebrations. With ten bedrooms split over two floors, The Manor can cater for various groups, be it three or four families using the rooms as family suites, or individuals and couples sharing a weekend away to relax. | https://www.middlelittletonmanor.com/destinations/uk-england-worcestershire/manor-houses |
CITY Groups are the central hub of church life at New City. These groups are designed so the family of God at NCC will be known, cared for, built up in the gospel, equipped, and sent out to proclaim the gospel in Word and Deed.
WHAT TO EXPECT?
A trained leader(s) who oversees the spiritual life of the group under the care/oversight of the elder team; ensuring people are known, loved, and included in the family of NCC. Second, shared meals to encourage hospitality and friendship. Third, sermon-based Bible discussion/study with the intent of applying the Word of God to all of life. Fourth, times of prayer and encouragement for the sake of gospel growth and gospel mission in the world. Fifth, opportunities to serve one another and our city using the gifts God has given for his service. Sixth, life together is always better than life alone... This means laughter, fun, and joy!
These smaller gospel communities meet weekly at different times and places throughout the Kansas City metro-area. Theses groups are always open; so find a group near you, fill out the form below, and get connected.
CITY Group Sign Up (CITY Groups Winter Quarter begins January, 2019 *Groups are always open)
. | http://newcitychurchkansascity.org/city-groups |
- This event has passed.
Case solving with LINC Research and Analysis
January 20 @ 4:00 pm - 5:30 pm
LINC Research and Analysis provides Lund University students with the opportunity to practice Financial Analysis, Equity and Quantitative research together with ~ 40 other ambitious student analysts. As an analyst, you will start building your professional network, get exposure towards finance professionals and learn how to apply theoretical concepts in practice. Previous analysts from R&A have received offers from prestigious firms such as Fidelity Investments, Goldman Sachs, J. P. Morgan, Deutsche Bank, ABG Sundal Collier, BNP Paribas, Nomura, SEB, Nordea and more.
If you are interested in applying to LINC R&A, we recommend attendance at this event. During the event, we will introduce R&A, and you will get the opportunity to practice your case solving skills within the space of equity research. Furthermore, you will get the chance to meet some of our talented team leaders who will aid the student analyst of R&A during this term and learn more about the recruitment process, giving you an edge while preparing your application.
When: Wednesday, January 20th, 16:00-17:30
Where: https://zoom.us/j/98998132087
Where: https://zoom.us/j/98998132087
How to apply for R&A: If you want to become an analyst within LINC R&A, please visit https://linclund.com/researchandanalysis/, scroll down, and click “Apply” to be taken to the application form. You will then be asked to submit a cover letter (no more than 250 words) and a resume according to the following template:
In addition to the 250 words limit for the cover letter, feel free to write about a stock you like and outline why (no more than 500 words total).
Please attach your documents as PDF and submit your application no later than January 24th at 23:59. All students at Lund University are welcome to attend this event and apply for R&A. Applications open on the 11th of January. | https://linclund.com/event/introduction-to-ra/ |
Don’t worry if you’ve never heard of whisker fatigue. It isn’t necessarily a well-known disease. However, for some cats, it has a negative effect on their everyday lives.
What Whisker Fatigue is?
Cats have thick whiskers that protrude from their noses, behind their eyes, chins, and the backs of their front legs. Sensory collecting nerves abound in them. It gathers information about the cat’s surroundings, such as objects, movements, and wind currents. They help cats hunt in the dark and play an important role in their communication system.
When something rubs up a cat’s sensitive whiskers, like a food or water bowl on a regular basis, it may cause whisker fatigue. It causes discomfort and even pain, as well as tension when eating and drinking.
Whisker receptors are primarily activated by a cat’s autonomic system, which consists of sympathetic and parasympathetic nerves. These nerves respond to the internal and external environment without conscious control. Cats will voluntarily “turn on” the sensory focus of their whiskers in the exact location they want (pupils constricting in response to bright light, for example).
Whisker exhaustion can be thought of as a knowledge overload that causes your cat to become stressed. Whisker hairs are so responsive, They send signals from the sensory organs at the base of your cat’s whiskers to her brain. So, any time she comes into contact with an object or senses movement, even if it’s only a tiny shift in the air current or a gentle brush against her face.
Whisker exhaustion is not a disease (and no link to any illness}, and frequent interaction with food and water bowls tends to cause it. A depressed cat, on the other hand, is unhappy. If she refuses to eat or drink, she may become malnourished and/or dehydrated.
What Are the Symptoms of Cat Whisker Fatigue?
The following are symptoms that your cat may be suffering from whisker fatigue:
1. Pawing at or removing food from the bowl to eat it on the floor
2. When eating or drinking, making a huge mess around the dish.
3. Leaving food in the bowl when acting hungry.
4. Trying to approach the bowl of food with caution, behaving as if he or she wants to eat but nervously walking around first
5. Demanding that the food bowl be kept filled to the brim at all times; refusing to eat if the bowl is not full.
6. During mealtimes, behaving aggressively against other pets or people in the house.
What Can Be Done to Prevent Whisker Fatigue?
It’s as simple as replacing your cat’s food and water bowls to avoid or stop stress-related whisker exhaustion at feeding time. Provide a flat surface or a wide-enough bowl for cat food so her whiskers don’t hit the bowl’s edges. Use a paper plate as a food tray.
Most cats prefer to drink from a lipless, big flowing water stream. Pet parents should ideally have an automatic, freshwater supply for their cats. It includes a cat water fountain, which cats prefer, to an icky, stale bowl of water.
Some cat parents assume that trimming their cats’ whiskers is another option, but this is a no-no. Trimming whiskers muffs their expressions dims their senses, and generally confuse and annoy cats. You should not trim cat whiskers.
Should You Take Your Cat to The Veterinary for Symptoms of Whisker Fatigue?
In most cases, simple changes to how you feed your cat and the dish you use will eliminate any signs of whisker fatigue. If you’ve made the required adjustments and your cat always seems worried about feeding, call the Cat Hospital. It can ensure there aren’t any more serious issues at hand. | https://blogtion.com/whisker-fatigue/ |
Pangong Lake(aka. Pangong Tso) is an international lake located in the Himalayas at the height of approximately 4,242 meters, at the junction of China's Tibet and Kashmir. "Pangong" in the Tibetan language calls "Cuomu Angla Renbo Tso", which means "long-necked swan". It's the longest rift vally lake in the world. There's the highest bird island in the world, located in the northwest of Ritu County, Ngari Prefecture, Tibet.
China controls about two-thirds of the eastern part of the lake, and India takes about one-third of the western part. Pangong Tso covers an area of 604 square kilometers. The strangest thing about the lake is that it is a lake with different amounts of salt in the water from east to west. In other words, the east is a freshwater lake(in China), the middle is a semi-saline lake, and the west is a saline lake(in Kashmir).
Overview
Pangong Tso is located in the western part of the Tibetan Plateau. It's 155 kilometers long from east to west and it's narrow from north to south. The narrowest point is about 40 meters. It covers an area of 604 square kilometers and the deepest is 41.3 meters. The lake has a maximum depth of 41 meters and an average depth of 5 meters. The ice epoch of Pangong Lake is about six months a year.
It is an inland lake with beautiful scenery, clear water, and snow-capped mountains surrounded in the distance. The lake is quite clear as the visibility can reach 3 to 5 meters. Due to factors such as light, depth, and brightness, it presents different colors such as dark green, light green and dark blue, which are very amazing. At night, you can see the starry sky, as well as the reflections on broad water, which is quiet and deep.
- Location: Ritu County, Ngari, Tibet
- Opening hours: 08:00 - 16:00
- Ticket price: CNY 30
- Suggest visit time: 3 - 4 hours
- Best travel time: May to July
Animals of Pangong Lake
There are more than a dozen islands of varying sizes in the lake, among which the most famous is Bird Island. It's named after the nests of waterbirds on the island. Bird Island is the highest bird island in the world, as well as the kingdom of birds. It is located about 12 kilometers northwest of the Ritu county in the Ngari region, at the junction of the Nagri region and Kashmir.
Bird Island is small in size, about 300 meters long and 200 meters wide. There are no big trees on the island, only some low shrubs, and some unnamed grasses growing along the coast. Due to the good ecological environment, thousands of gulls on the island live here. The gulls and the Anatidae flying on the wind, covering the sky, which has become a major spectacle of the Ngari Plateau. There are about 20 kinds of various birds on the island, and the number can reach tens of thousands at the most.
The main birds are bar-headed gooses, brown-headed gulls, great black-headed gulls, crested ducks, red ducks, etc., among which bar-headed gooses and the brown-headed gulls have the largest number. It takes about 30 minutes to reach Bird Island by boat from the shore. However, for the protection of birds, it is not allowed to land on the island. You can only enjoy this magical bird kingdom around this Island.
Pangong Lake is also a fish world. There are a lot of aquatic plants in the lake to provide a good habitat for fish. There are more than 10 species of fish. In the lake, there are endemic Tibetan fish, such as snowtrout, especially famous for not growing scales.
Best Time to Visit Pangong Tso
From May to July each year is the best time to travel to Pangong Tso. The weather in Pangong Lake at that period is fine, the surrounding scenery is stunning and there're thousands of birds come to Bird Island to breed offspring. Bird watching in Pangong Lake is a famous tourist highlight in the Ngari region and even in Tibet. Up above there're blue sky and white clouds; down below there're snow-capped mountains and lakes. At the same time, here you will feel the harmony between the natural and the animals.
During this period of time, the average annual temperature of Ngari is 19℃. The altitude of this area is more than 5000 meters, and there's a great temperature difference between day and night. In summer, the temperature in the daytime is above 13 ℃, however, it drops to below 0℃ at night. So it's necessary to take enough warm clothes if you're traveling here. From the end of October to the end of April of the following year, the Xinjiang-Tibet Highway is blocked by heavy snow.
Pangong Lake Travel Tips
1. Prepare Necessary Documents:
As Pangong Lake is located in a strategically important area, you need to obtain a permit to visit the lake. An inside line permit (ILP) is required to visit Pangong Lake. Foreign tourists need to obtain a Protected Area Permit (PAP).
2. How to Get to Pangong Lake？
Pangong Lake is located about 12 kilometers northwest of Ritu County, Ngari, Tibet. It's 1,800 from Lhasa to Ritu County, which takes at least 3 days. Alternatively, you can drive along the Xinjiang - Tibet Highway. It's about 129 kilometers northwest of Shiquan Town.
3. Ticket and Boat Ride
The ticket for Pangong Tso is CNY30. If you want to take a boat trip, you need to pay another CNY 80 for renting a boat. A boat ride from the shore to the bird island in Pangong Lake takes 30 to 40 minutes. On the way, you can enjoy the gorgeous scenery of Pangong Lake and the magnificent scenery of remote mountains.
Lhasa - Gyantse - Shigatse - EBC - Saga - Lake Manasarovar - Darchen - Mt.Kailash Kora - Zada - Gegye - Gertse - Shigatse - Lhasa
20days
$4020Per Person
Witness the magnificent landscape of western Tibet, experience 3-day kora and explore the lost civilizations of Ngari.
Lhasa - Shigatse - EBC - Lake Manasarovar - Mt. Kailash - Guge Kingdom - Ali - Gegye – Gertse - Shigatse - Lhasa
19days
$3939Per Person
Uncover all must-see attractions in central and western Tibet. Get ready to be impressed by its in-depth charm.
Email response within 0.5~24 hours. | https://www.greattibettour.com/tibet-attractions/pangong-lake.html |
I’m Irish, but live over in Czech republic, I’m back in the sport after 10 years (I did a race called the FBD Ras, 8 day affair – popular with strong UK riders, its a 2.2, its my modest claim to fame) I have a coach based in the US. A former student of Hunter Allen – he is good and works you hard.
This season I rode a 6 minute hill climb and was 9th overall and 3rd age group, big event. About 6 minutes at 6%, and I hit 400w at 65kg. Good for me but I got beaten by 15 seconds so a rather convincing defeat. I have since done 430 for 5 minutes and am averaging about 500w in minute on 3 minute off repeats – about 10 of them.
But my question is about a comment you made re flat vs hill power. Riding 320w for 10 miles, one would think that at 450 for 5 minutes you would be way higher that 320 – is this a deliberate training choice ? or you found it to be a physiological limitation ? I’m about similar to 320 for 20 minutes on the flat – but it is growing, and my curiosity lies in how far I can take the longer efforts.
I’ve just got back from Czech Republic (Zlin) over weekend. So will answer as blog post.
In 2015:
- My max power for 10 mile TT (20 mins) was about 338 W this summer. (Quark)
- My max power for hill climb (5 mins) is about 450 watts. Though it may have been closer to 470 for last few climbs I did without any power meter.
There are a few reasons.
- They are different power meters, I think hill climb bike (Stages) gives slightly more power than Quark.
- If I did a 5 minute TT on the flat, (I’ve never actually tried.) but, I would be very surprised if I could get anywhere near 450 watts. In other words, it is easier to post a higher power figure for a steep climb on road bike than a flat 5 minute TT bike test.
Why more power for short hill climbs?
- You can get more power on a steep hill, when you stand on the pedals rather than stay seated (I think it is due to the extra use of body weight increasing power.)
- Different physiology for hill climb vs TT bike. I’ve not tested, but it might be easier to get more power on a road bike. Depends how much you train on TT bike too. Certainly, if you’re not used to riding on TT bike, you need to spend time getting used to different muscles used.
- I don’t train only for 5 minute climbs. One interesting thing is that at end of time trial season I can get close to my max 5 min power for hill climbs. Two months of specific hill climb training does increase 4-5 minute power a little, but less than you might expect. But, I also train for 10 mile TT, by doing five minute intervals.
Secondly I’m not sure I fancy spending 10k on a tt bike for next year. I may buy an old Stuart Dangerfield frame I found, and might just build it up with newer wheels and a good cockpit. Do you believe in the 10k spend for tt bikes?
Yes and No. I did spend a lot on my TT bike (Speed Concept), but then it wasn’t that much quicker than my previous Trek Equinox that I sold for £750 on ebay.
The simple answer is you don’t need to spend 10k on a bike. For example, winner of UK national 10 spent £1k on bike (he got a lot of aero coaching / wind tunnel testing, which is probably expensive, but probably more effective than spending money on a bike.)
If you go Ultegra mechanical rather than Dura Ace Di2, you can save $4-,$5000, but the difference in speed over a 25 mile TT is practically ‘nothing’. I still bought Dura Ace Di2 though. You might be better off spending a lot of money on skinsuit, helmets and aero-testing. See also marginal aero gains
Next year I just want to develop, not winning doesn’t bother me too much as I just want to build the engine. (I was 30th in the non UCI nationals here of 340 riders – on an R3 with t-bars)
A simple TT bike can help improve over a road bike with t-bars. But, I agree the real test of time-trialling is building your engine and seeing how you can stretch your performance. Aerodynamics do make a lot of difference to your speed, but for me the real buzz comes from improving performance – not relying on aero improvements. | https://cyclinguphill.com/questions-on-five-minute-efforts-vs-10-mile-tt/ |
Here’s how environmental justice leaders are pushing forward in the Trump era
These are challenging times for environmental justice — at least at the federal level. Earlier this month, Mustafa Ali, who led environmental justice work at the U.S. Environmental Protection Agency, resigned rather than preside over the dismantling of his program.
To understand the prospects for environmental justice work in Trump’s America, we gathered (by phone) an impressive cadre of leaders from across the country:
Q.Ellison: In the Trump era, the prospects for progress on environmental justice at the federal level seem rather grim. But even in this political landscape, there’s discussion about building alternative systems. What are those exactly?
A.Martinez: When the political system does not provide for the common good, those that deal with the consequences have to be creative, innovative, and action-oriented. And we do see that. All kinds of communities are coming together to try and figure out how to build systems that are both environmentally sustainable and equitable. Cities are leaders in developing plans on climate action and adaptation, irrespective of what federal legislation or international agreements are in place. That kind of action is feeding into a locally based national and international movement. The challenge continues, though, to move states and cities to incorporate justice into their institutional work.
Abdul-Rahman: Communities on the front lines can lead the way. We’ve formed a group called Women’s Voices Unheard [in Indianapolis], and we’re asking the women about their concerns and issues. We give them the tools and the knowledge they need to speak for themselves.
We look at the contrasts between communities. Who gets to have an aesthetically pleasing environment? Which community gets the natural gas plant that emits methane, or the coal-fired power plant? Who gets to decide about issues affecting the community? Then we look at another vision of how we can control our own destiny by honing in on solar and wind, and how our communities can benefit by getting the training and the jobs. We present another vision of the future, where we as human beings and as communities can change our own destiny. We can utilize our power and speak truth to power.
Adrar: With the issues we’re facing in frontline communities, we can go issue by issue, rule by rule — or we can look at the underlying root causes. We see the enclosure of wealth and power; Trump’s cabinet is one of the wealthiest in modern history. That creates an opening for greater extraction of fossil fuels and more human rights violations in our communities. So as our Native friends [who’ve been] marching in D.C. are saying, we have to end this colonial mindset.
Yeampierre: We need to build an economy that is not extractive, but regenerative. In our industrial waterfront community [in Brooklyn], we’ve been working with industries to operate in a way that’s cleaner, retrofitting to reduce emissions. Our vision is to use the industrial waterfront as a place that creates good jobs in green industries — like building offshore wind turbines or community-owned solar. We see this as a solution that could prevent people from getting displaced, while addressing climate change and environmental justice.
Q.Ellison: Displacement is a big problem: As people are pushed out of gentrifying cities, we are seeing the rise of poverty in suburban areas and surrounding exurbs. How do you discuss and address that?
A.Martinez: I think it points to the deep structural issue that Angela talked about. There was a racial and class dimension to suburbanization in the first place. Suburbanization could not have happened without federal policy constructing a highway system that destroyed many communities of color. The reason many of our communities of color are in the state that they are in is because of federal policy and housing policy that promoted segregation, and redlining that extracted capital from certain communities to the benefit of others. So it was not an equal process.
We’ve been able to institute some policies and laws that hopefully prevent the most egregious of those abuses, but the reality is that the dynamic still continues. So now white middle-class people are leaving the suburbs, which leaves these areas open to people of color and low-income communities. The amenities move with the capital and with the middle class, and the low-income communities that are left behind suffer.
Q.Ellison: Those low-income communities of color are going through some real struggles and disruptions on the economic front. So there’s got to be a tug-of-war between the need for jobs and economic growth in those communities and protecting the environment and the climate. How do you strike that balance?
A.Yeampierre: It doesn’t have to be one or the other. The clean energy jobs we are promoting in the industrial waterfront pay $60,000 a year, and come with benefits. That would make it possible to retain the community, to keep people from being displaced. But the New York City Economic Development Corporation is going with conventional development models that would basically turn our community into a workforce for the privileged in their own communities. There is an opportunity to do it differently — to address climate change and create jobs.
I completely agree with what Cecilia is saying. In our community, we’ve had to bear all the environmental burdens. But the moment we start fighting for the amenities, all of the sudden we can’t afford to live here anymore. Even our successes have displaced us. So our park, our greenway, the fact that we stopped a power plant from being sited in the neighborhood — all of our victories are being used by developers to displace us.
Martinez: The reality — at least in the communities I work with — is that people are very aware of environmental issues and that it isn’t a tradeoff between economic development and environmental sustainability precisely because of the public health impact. So in our communities — whether they’re Latino, African-American, or Native — there isn’t the kind of disconnect that is popularly assumed between environmental sustainability and economic development. The question is, how do we bring those two together with the appropriate investment and in a way that is equitable and provides the kind of benefits these communities have been lacking in the past?
Adrar: I really appreciate that because, based on the intersectional work we’ve been doing since the administration came into power, it’s clear that groups are mobilizing around environmental issues in a way that makes sense to them, using a different narrative than what we’ve been used to hearing in the media around carbon emissions.
We understand that climate change is a catastrophe: It’s going to lead to flooding, droughts, and it’s going to shift migration around the country and around the world. But groups are looking at how to create solutions for that. We are talking about a “just transition” away from the extractive economy and creating tools for reinvestment in communities. We want to create safeguards and make sure that public investment goes into these communities in ways that lead to community control of energy and resources. I just got off a Movement for Black Lives conversation yesterday and they’re talking about divestment and reinvestment. Indigenous groups have moved incredible amounts of money from the fossil fuel industry.
Q.Ellison: Does the new political and social environment change how you think and strategize?
A.Abdul-Rahman: Indiana is now a hyper-conservative state, and we are continuously battling a lot of bad policy. So we find ourselves battling redistricting deals and anti-Ban the Box laws and laws against obstruction of traffic to prevent folks from being able to protest. For us it just means we need to organize more intensely and intentionally. For example, our communities — when they’re inundated with pollution — need to advocate for community benefits agreements, so they can benefit from the jobs and the movement of making their communities cleaner and better.
Q.Ellison: The innovation sector is so focused right now on creating technologies of convenience and efficiency. The word disruption is used quite a bit. What sort of pressure could we put on the innovation sector, on Silicon Valley, to develop technologies that help heal the planet?
A.Yeampierre: I think that these innovators should have people representing frontline communities at the table before they even shape these technologies. There is technology called carbon capture and sequestration that we oppose because it keeps us dependent on coal and other fossil fuels. So although it may be innovative, it is still not environmentally just.
So these folks could start by having a conversation with communities, saying, “What do you need, and how can we use our skills, our resources, our power, and our access to technology to address community needs?” Instead, what they do — because they’re competitive and top-down and their behavior mirrors the problem that got us here in the first place — they create technology that we then have to stop, to react to, to respond to.
Adrar: At COP22 at Marrakesh [the 2016 United Nations Climate Change Conference], when [then-Secretary of State] John Kerry said that the private sector was going to be the savior of the climate, we knew there was going to be favoritism toward techno-fixes and market-based solutions. I don’t want our energy sector to make the same mistakes that the industrial agriculture sector made. We’re overproducing food, but there are still hungry people on the planet, and we’ve overlooked ancestral wisdom and knowledge from native peoples, peasants, and people who’ve lived on the land.
Martinez: We have to keep in mind that technology is not neutral. Technology embodies certain social and political principles, for better or worse. Our energy system is a major contributor to climate change, and we have not integrated its social cost, its environmental cost in the market of technology development. We have an obese energy system, which is geared toward producing an abundant supply of energy year after year, into the next century. But what is the role of our community in managing, operating, and making decisions about that energy system? We need to ask: Energy for what? And energy for whom? And how do we incorporate those costs? That’s inherently what energy democracy is all about.
Q.Ellison: What are you working on right now?
A.Adrar: What aren’t we working on? A lot of our groups are working on rapid response, collaborating to be more responsive to direct threats to communities — on issues like immigration, police abuses and the defense of black lives, and the indigenous struggle. The Climate Justice Alliance just put forth a new strategy plan that has an ambitious goal of developing 50 Just Transition campaigns around the country, which means we’ll be working with communities to understand the framework, share tools, and develop collective strategies.
Yeampierre: We’ve got three community-owned solar initiatives, and we’ve spent a lot of time thinking about what governance and financial engineering look like for a utility that would be owned by low-income people. And, in partnership with the Climate Justice Alliance, we are organizing the largest gathering of young people of color on climate change in the country, scheduled for Aug. 3 this year at Union Theological Seminary.
Abdul-Rahman: Our main mission is to work on energy-efficiency policy and climate resistance and moving more renewable, clean energy. In East Chicago, where drinking water is contaminated by lead, we are delivering water and filters and helping the people lift up their narrative. We recently filed a petition with some other groups to rebuild East Chicago’s water infrastructure, which is connected to making the community resistant to climate change and creating a new vision. In lieu of being gentrified, could we build affordable housing there? Could this affordable housing have solar on it? And who gets to build that? We want to help move that community forward toward a just transition.
Martinez: We are continuing to do research on how you develop climate-resilience indicators from the perspective of communities, particularly communities of color and low-income communities. I think everybody on this call is also working on a very important national initiative called Building Equity and Alignment for Impact, which is about shifting philanthropic and other resources to grassroots community organizations and environmental justice groups that have not been funded at the level of larger mainstream environmental work. And, given that the federal state of the art right now is problematic for moving environmental justice issues, we continue to look for other policy levers at the state and local level. | |
What is contra dancing?
Contra dancing is a form of North American folk dance in which the dancers form two parallel lines that run the length of the hall. In its simplest form, it is danced by pairs of couples. One lady and gent face another lady and gent. Under the direction of a caller, each couple dances a sequence of figures with each other and with the other couple, for 64 beats of live music. Then each couple moves forward to meet another couple, and they repeat the same figures. When a couple reaches the end of the line of couples, it turns around and comes back the other way. Eventually each couple dances with every other couple in the set.
Normally, the caller teaches each dance before it is actually done to music. This gives everyone an idea of what to expect, and an opportunity to practice the figures. The caller calls each figure just before it is about to begin, hence the dancers can perform the figures in time to the music. Once the dancers appear to have mastered a particular dance, the caller may choose to stop calling, leaving the dancers to enjoy the movement with music alone. Many of the basic figures in contra dancing are similar to those in square dancing. Listed below are some of the most common contra dance figures. When a couple stand side by side, normally the lady is on the right and the gent on the left.
To see a PBS report on contra dancing in Maine, click here.
To see for yourself, check out the TCD schedule here.
What to expect at your first dance
Beginners are welcome and you do not need to have any prior dance experience. Also, you do not need to bring a dance partner with you. A beginners class starts at 7:30 PM so you will learn everything that you need to know to be able to contra dance. The dance starts at 8 PM and ends at 11 PM. We also recommend that you dance with experienced dancers, rather than dancing with other beginners, since your experienced partner can guide you through the dance. Anyone may ask anyone else to dance so don't be shy about finding a partner and getting on the dance floor.
What should I wear?
Wear loose, comfortable clothing, and dress to stay cool since you can expect to sweat. Many of us bring an extra shirt to change into partway through the dance.
Shoe policy
To protect our floors:
- Shoes must be clean and soft-soled
- No spike heels may be worn; heels must be wider than 3/4 inch
Quotes
"O body swayed to music, O brightening glance, How can we know the dancer from the dance?"
- William Butler Yeats, "Among School Children"
"Any problem in the world can be solved by dancing."
- James Brown
"You've gotta' dance like there's nobody watching, Love like you'll never be hurt, Sing like there's nobody listening, And live like it's heaven on earth. (And speak from the heart to be heard.)"
- William W. Purkey
"To watch us dance is to hear our hearts speak."
-- Hopi Indian saying
"Dancers are the athletes of God."
-- Albert Einstein
"Those who dance are considered insane by those who can't hear the music."
-- George Carlin
Figures for two dancers
- BALANCE: Holding one or both hands, each dancer takes two steps toward the other, and two back.
- SWING: In ballroom position, each dancer walks around the other. Optionally, this can be performed more like a pivot, with the right foot held in and a scooter-like "buzz" step used. There are several variants to the ballroom position. A swing always ends with the lady on the right and the gent on the left.
- ALLEMANDE: The dancers walk around each other, holding right (left) hands with fingers pointing up.
- GYPSY: Similar to a swing or allemande, but with eye contact only.
- DOS-à-DOS: (also known as do-si-do) The dancers walk around each other, remaining back-to-back, passing right shoulders as they move forward and left shoulders as they return.
- SEE-SAW: A dos-à-dos in the opposite direction.
- BOX the GNAT: Holding right hands throughout, lady and gent face each other. Each moves forward and makes a half turn (lady to the left and gent to the right) until they finish in each other's original places.
- CALIFORNIA TWIRL: Lady and gent begin side by side facing in one direction, and finish side by side facing in the opposite direction. They raise their joined hands, and both walk forward in a semicircle, the lady passing under the raised hands and the gent passing outside the lady.
Figures for four dancers
- BALANCE the RING: Hands held in a ring, all four dancers take two steps forward and two back.
- CIRCLE: Holding hands in a ring, all four walk to the right (left).
- STAR RIGHT: Holding right hands in the center, all four walk to the left.
- STAR LEFT: Holding left hands in the center, all four walk to the right.
- PROMENADE: Two couples face each other. In skater's position (left hand in left, right hand in right), each couple crosses to where the other couple was standing, the gents passing left shoulders.
- LADIES' CHAIN: With two couples facing each other, ladies pass each other, taking right hands and giving the left hand to the opposite gent, who turns the lady forward while he walks backward, until both once again face the other couple. The turn portion is called a Courtesy Turn.
- RIGHT and LEFT THROUGH: Two couples face each other. Each dancer passes the opposite dancer by the right shoulder, optionally taking right hands, then each couple takes left hands for a courtesy turn.
- DOWN the HALL: Four dancers in line (in an order specified by the caller) walk together away from the music.
- HAY: All four dancers, with eye contact only, simultaneously dance a figure-eight pattern in which each one returns to the starting place. This is easier to demonstrate than to describe.
Prepared by Peter Calingaert.
Contra dance etiquette
Contra dancing... high energy, whirling, twirling fun! To foster a safe, friendly atmosphere, TCD offers the following suggestions:
- Wear loose, comfortable clothing, and expect to sweat. Many of us bring an extra shirt to change into partway through the dance since we think dancing in a dry shirt is more fun—and our partners agree! Drink lots of water: Dehydration is no fun, even if water leads to more sweating. Please also wear sturdy, clean, soft–soled shoes to protect our floor. Many dancers bring shoes that they put on at the dance.
- Contra dancing, unlike most sports, throws you into the arms of another new person every few seconds. Some dancers are hypersensitive or allergic to highly scented products such as perfume, after–shave, cologne, etc, and others react to odors such as spices, onions or garlic. Please be thoughtful in your pre–dance scent application. And, yes, fresh bathing and clean clothing win you points.
- Anyone may ask anyone else to dance. Same–gender dance partners are common. To be welcoming and to help people not fear rejection, we also cultivate a community in which you generally accept an invitation to dance unless you have good reason not to.
- Many experienced contra dancers improvise during a dance. We encourage artistic expression and experimentation, but being on time and helping your partner be on time are always more important than nifty embellishments.
- Dancers flirt to various degrees. Contra dance flirting is usually meaningless fun, but of course dancers do also find romance on the floor. Please pay attention to your partner's comfort with flirting.
- People dance in close physical contact—but please hold yourself so that both you and your partner are comfortable. Remember that your partner's comfort zone may be different from yours!
- Eye contact can help prevent dizziness during swings and allemandes. Eye contact is also fun, friendly, and flirty. If you're not comfortable with eye contact, try using your partner's ear, chin, collar, etc., as a dizziness–preventing focus—but be careful not to focus your gaze anywhere that could make your partner uncomfortable (e. g., down at a woman's chest!).
- You should be comfortable at a contra dance. However, different people are comfortable in different ways, so dancers can have a mismatch. In the event that someone approaches you or dances with you in a way that makes you uncomfortable, here are some suggestions: Your comments will probably be most effective in person, especially if the other dancer is unintentionally causing you physical pain. We suggest gently and forthrightly saying, "Please don't do X. When you do X, it makes me feel Y. I would prefer it if you do Z." This feedback can help people learn and grow. Remember that in all likelihood this person has no desire to make you uncomfortable and will be appalled at themselves and grateful to you when they find out. If approaching this person by yourself doesn't feel possible, please discuss the issue with a board member (TCD Board) and we will work with you to solve the problem. If you're not sure who board members are, please ask the person who made the announcements.
- We welcome children. However, please keep your children who are not dancing off the dance floor for safety on all sides.
- Contra dance demands coordination with yourself and with others. Dancing under the influence, just like driving, can be a tricky proposition. Please be responsible, especially so that your dancing doesn't impair the rest of the set.
Videos
Instructional videos by Chattahoochee Country Dancers
- Introduction
- Two Dancers
- Four Dancers
- A Contra Line
- Come Dance With Us
- A Called Dance #1
- A Called Dance #2
- The Basics
- Contra Video Credits
They also offer a higher resolution DVD version of these videos.
Other
Santa Barbara Country Dance Society has a good page: What is Contra Dance? | http://www.tcdancers.org/aboutcontra.html |
For the benefit of our members (and the broader writing community), we’ve collected this list of current competitions and opportunities for you. Please note that we do not administer these competitions, and we can’t answer any questions you might have about them.
You can also subscribe for our competitions newsletter here.
April
Poetry publisher Recent Works Press is open 1-30 April, 2020, for submissions.
Griffith Review 70: The Novella Project VIII (fiction and creative non-fiction ranging between 15-25k words on ‘generosities of spirit’, no fee, publication) has been extended to 7 April 2020.
The Neilma Sidney Literary Travel Fund offers grants of $2000-$10,000 towards writing-related travel. Applications close 15 April, 2020
The Rachel Funari Prize for Fiction (fiction of up to 2000 words that engages with ‘future’ by Australian women or non-binary authors, entry fee, cash prize) closes 17 April, 2020
Science-me a story is accepting science-related submissions that engage primary school age children. Prizes offered, submissions close 20 April, 2020
The 2020 Heroines Women’s Writing Prize & Anthology (short fiction and poetry accepted from writers who identify as women, entry fee, cash prize and publication) closes 20 April, 2020
Positive Words Short Story Competition (short stories up to 2k words, poetry up to 48 lines, cheap entry fee, cash prize) closes 23 April, 2020
The 2020 Picture Book Competition (picture books manuscripts, entry fee, cash prizes and a mentorship for first) closes 27 April, 2020
The 2020 Daisy Utemorrah Award (open to all Aboriginal and Torres Strait Islander peoples living in Australia, junior or YA fiction, cash prize and publishing contract) closes 30 April, 2020
Furphy Literary Award (story on Australian life of no more than 5000 words, no entry fee, prize includes cash prize, a university residency and publication options) closes 30 April, 2020
POETICA CHRISTI PRESS 2020 Annual Poetry Competition (poems on the theme of ‘joy in the morning’, entry fee, cash prize publication) closes 30 April, 2020
KYD Unpublished Manuscript Award (includes Varuna fellowship for short-listed writers, cash prize, subscribers only) closes 30 April 2020
Davitt Awards for the best crime and mystery books by Australian women (submit copies of books, trophy) close 30 April 2020
Queenscliffe Literary Festival micro-fiction writing prize (free, Victoria writers only, prizes TBA) seeks pieces of exactly 50 words via email by 30 April 2020.
CRAFT short story prize (cash prize, entry fee, stories to 5000 words) closes 30 April, 2020
Best of Times humorous short story contest (cash prize, open theme, entry fee, stories to 2500 words) closes 30 April, 2020
Recent Works Press is accepting submissions up until 30 April for publication. Details on the site.
May
The Poetry d’Amour Love Poetry Contest (entry fee, cash prize, poems to 40 lines, enter by email) closes 1 May, 2020
Elizabeth Jolley Short Story Prize (short stories of 2000 to 5000 words, entry fee, large cash prize) closes 1 May, 2020
Lord Mayor’s Creative Writing Awards (several categories with up to $12,000 in prizes, free) for unpublished emerging writers closes 3 May 2020
The Golden Pen Writing Award (under 18s only, variety of written and drawn genres on ‘planet earth’ no fee, various prizes) has been extended to May 10, 2020
US-based Book Pipeline adaptation contest (published work, entry fee) for its adaptation has an earlybird deadline of 20 May, 2020, closing on 31 August, 2020.
Fellowship of Australian Writers Literary Competition (multiple categories/genres, entry fee, cash prize) closes 15 May, 2020
Grieve Writing Competition (short stories (500 words) and/or poetry (36 lines) on the theme of ‘grief’, entry fee, cash prize, publication) closes 25 May, 2020
The Australian/Vogel’s Literary Award (longform work by an author under 35, entry fee, cash prize and publication) closes 31 May, 2020
HarperCollins’ The Banjo Prize for adult commercial fiction (publication and $15,000 advance, two runner-up prizes) closes 29 May, 2020
June
US-based Book Pipeline contest (entry fee) for unpublished manuscripts has an earlybird deadline of 1 June, 2020, closing on 5 October, 2020.
2020 Bruce Dawe National Poetry Prize (entry fee, cash prizes) closes 5 June 2020
Adelaide Plains Poets Poetry competition (poetry to the theme of ‘vision’ in an open and junior category, entry fee, cash prize) closes 26 June, 2020
ARA Historical Novel Prize ($30,000 prize, for books published 1 Jan 2019-30 June 2020) opens 1 May, closes 30 June 2020
Dorothea Mackellar Poetry Awards (students only, cash prizes, various categories) close 30 June 2020
July
The ACU Poetry Prize (cash prizes, theme “generosity”, entry fee) opens 6 April and closes 6 July 2020
August
Sydney Hammond Short Story Writing Competition 2020 (stories up to 1000 words on the theme of ‘if only’, entry fee, publication) closes 1 August, 2020
St Kilda Historical Society Short Story Competition (open and junior sections with different word limits for stories in or inspired by St Kilda, entry fee, cash prize) closes 7 August, 2020
Ongoing Opportunities
The COVID-19 collective dream journal is looking for dreams and hallucinations experienced during the COVID-19 pandemic. No payment, but collected accounts will be published. You can submit your experiences here.
The Australian Bush Poets Association run a calendar of bush poetry events for both written and performed bush poetry.
Ginninderra Press (accepts unsolicited manuscripts across a range of genres, please read their criteria carefully).
Wombat Books (accepts unsolicited manuscripts, submitting authors should be familiar with WB’s body of printed books).
Brow Books (the book publishing arm of The Lifted Brow) currently has submissions open for non-fiction books.
LitMag is looking for fiction, poetry and non-fiction submissions (submission fees, paid).
Utterance journal is looking for female, trans and non-binary writers to submit poems and short non-fiction on their life. Submissions open monthly and are capped at 100 total, so keep an eye on this one.
Babyteeth journal is looking for a variety of content (including photography, scripts and illustrations). There is a small payment for contributors.
Transcollaborative is looking for people to help with a translation project (no second language required) (paid)
Furious Fiction begins on the first Friday of every month, there is a cash prize for the best story in the month. | https://www.ballaratwriters.com/competitions/other-writing-competitions-and-opportunities/ |
FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION
SUMMARY OF THE INVENTION
DETAILED DESCRIPTION OF THE INVENTION
The field of the invention generally relates to electronic devices which utilize the global positioning system (“GPS”) to determine locations and distances, and more particularly to a GPS device for determining distances to features on a golf course, and displaying the distances to features, golf course images, and/or other golf related data. The invention also relates to systems and methods for supporting such a GPS device.
Various golf GPS devices, both handheld and golf cart-mounted, have been previously disclosed and described in the prior art. Generally, these devices comprise a GPS receiver and processing electronics (the “GPS system”), a display such as a liquid crystal display (“LCD”) or cathode ray tube (“CRT”), and a user input device such as a keypad. Golf course data is input and stored in the golf GPS device, including for example, the coordinates for locations of greens, bunkers and/or other course features. These types of devices use the GPS system to determine the location of the device. Then, the device calculates and displays the distances to the various golf course features, such as the distance to the front, middle and back of the green, or the distance to a bunker or water hazard. Accordingly, by placing the device at or near the golfer's ball, the device can relatively easily and accurately provide the golfer with important distance information usable while playing golf. For example, the distance information is used by the golfer to formulate strategy for playing a hole (sometimes called “course management”) and for club selection.
As an example of a golf GPS device, U.S. Pat. No. 5,507,485 (“the '485 patent”), which is hereby incorporated by reference herein in its entirety, purports to disclose a golf GPS device which can display depictions of a golf hole including multiple, selectable views of each hole such as the approach to the green and the green itself. The '485 patent describes that the device is configured to automatically determine the location of the device using a GPS receiver and then automatically display the golf hole view that would be of immediate interest to the golfer. Although the '485 patent discloses that the distance to displayed features may be indicated on the display, there is no description of how or where such information is displayed. The '485 patent also describes that the device may include other features such as means for receiving climate (i.e. temperature and humidity) and weather (i.e. wind speed and direction) conditions, means for recording and computing scores, bets and handicaps, means for recording details of a golf game sufficient to later replay and analyze a round of golf, means for suggesting shot and club selections to the golfer, clubs used and distances obtained for shots, and means for updating daily tee and hole positions on a removable integrated circuit (“IC”) card. The course data for each particular course is also described as being stored on removable IC cards which are interchangeable between a host computer and the golf computer.
However, the '485 patent does not describe how the course data is generated, or how daily tee and hole positions are determined. The means for updating and supplying course data through removable IC cards which are programmed on a host computer and then inserted into the golf computer is clumsy and inconvenient. Moreover, the '485 patent only describes a cart-based golf computer, and although the '485 patent suggests that portions of the device (the display and input means) could be implemented on a handheld unit such as the Apple Computer Company's NEWTON™, there is no enabling disclosure of a fully integrated, standalone, handheld golf GPS device.
U.S. Pat. No. 6,456,938 (“the '938 patent”), which is hereby incorporated by reference herein in its entirety, describes a handheld golf GPS device. The handheld device is described as software executed on a palm-held computer (PC) saddled into and connected directly to a dGPS (differential global positioning system or differential GPS) receiver. The handheld device of the '938 patent has a modular construction comprising a dGPS receiver module which receives and accommodates a display module. The display module is described as being any of a variety of handheld, multifunctional computing devices having a display screen and a processor running an operating system. Suitable display modules disclosed include Personal Data Assistants (PDAs), such as a Pocket PC, Palm™ PDA, or similar palm held computing device. The screen is split into two distinct sections, a course display section for displaying a graphic representation of an area of a golf course, and a separate data and menu display section for displaying touch sensitive menu buttons and data (including distances). In the disclosed embodiment, the majority of the screen includes the first section, and a thin, left column of the screen shows a vertical menu column of touch sensitive menu buttons and data, such as distances.
The '938 patent also describes that the handheld golf GPS device could be constructed so that the modules are integrated into one unit, but does not describe the construction of such an “integrated” unit in any detail.
The '938 patent describes various functionality of the handheld golf GPS device, methods of creating golf course maps, and methods of distributing the golf course maps to the handheld golf GPS devices. For example, to use the device of the '938 patent during a round of golf, course data is first loaded onto the device. This may be accomplished by mapping the course using the device and using that course data file, as discussed below, or by connecting the device to a personal computer (PC) or directly to an internet connection and downloading the course data file onto the device. There is a setup menu for setting player preferences such as: club selection and data gathering; lie and stroke tracking enabled/disabled; marking of green strokes; and setting the green reference point, system units, and course, tee and starting hole selections. Once the course, tee and starting hole have been selected, the device displays a graphical (icon) representation of the selected hole, and certain distances to features whose locations are pre-stored in the course data file is displayed only in the data and menu section of the display. For example, the distance to the center of the green may be displayed in one of the boxes in the data and menu section of the display. The graphical representation includes simple icons for various features to be shown on the display, as shown in FIG. 29 of the '938 patent. At any time, the location of the device is determined using the dGPS receiver.
The device of the '938 patent also includes a club selection feature, in which the average distance for the player's clubs is displayed for each shot during play. The device also includes features for distance measuring from the location of the device to a target marked on the display by the user. Another described feature of the device is a shot tracking method which allows the user to store the location of each shot and the club used for the stroke at such location. Several other features are described in the '938 patent, including display functions such as pan and zoom, score keeping, statistics tracking, and the ability to upload game shot data to a web site or PC and then view a replay of a round with the speed of replay being adjustable.
Another example of a handheld golf GPS device is the Skycaddie™ line of devices from Skygolf®. At present, there are four models of Skycaddies with various levels of functionality and features. Like the devices described in the '485 patent and the ‘'938 patent, the golf course data is loaded into the Skycaddie device. As described by Skygolf, the golf course data is generated by mapping each course on the ground using GPS and survey equipment. The database of golf course data is accessible through the internet on Skycaddie's website. The golf course data is downloaded onto a PC and then may be loaded onto the Skycaddie device by connecting the device to the PC. In addition, the Skycaddie devices allow a user to map a course, or additional course features, in the event a course or feature of interest is not included in the Skygolf database.
The Skycaddie devices use a GPS receiver to determine the geographic location of the device. Using the GPS determined location of the device and the golf course data, the Skycaddie devices display distance data such as the front, center and back of green. Certain models of the Skycaddie devices may also display the distance to features such as bunkers and water hazards whose locations have been pre-stored in the golf course data.
Certain models of the Skycaddies may also display an outline of the green for a selected hole with the distances to the front, center and back of green displayed to the side of the displayed outline. Some models also display an icon representation of certain features, such as a creek, bunker or green, in one section of the display and the distances to such features in a different section of the display next to the icons. The Skycaddie devices can only measure distance to locations which are not pre-stored in the course data by marking a starting location and then moving the device to the measured location and marking the ending location. The device will then display the distance between the two locations. However, this requires walking all the way to the measured location. The Skycaddie devices are configured to automatically advance to the next hole of play based on the location of the device.
However, none of the previously described golf GPS devices provides a convenient, pocket-sized form factor, a high-resolution color display capable of displaying photographic images of a golf course, flexible calibration to improve accuracy, or the functionality and ease of use to take full advantage of such features. Accordingly, there is a need for an improved golf GPS device which overcomes the deficiencies and drawbacks of previous devices and systems.
The present invention comprises a portable golf GPS device and system which is simple, accurate, and easy to use, yet provides excellent functionality and features in a compact, lightweight form factor. The portable golf GPS device of the present invention generally comprises a microprocessor operably coupled to a GPS unit, an input device such as a keypad (or touch screen) operably coupled to the microprocessor, and a display such as a liquid crystal display (“LCD”) operably coupled to the microprocessor. A program memory system which contains at least some of the software and data to operate the device is also operably coupled to the microprocessor. The device also comprises various firmware and software configured to control the operation of the device and provide the device functionality as described in more detail below. In addition, data utilized by the device, such as golf course data and images, may be stored in the program memory or other memory module such as Secure Digital memory card (“SD Card”), USB based memory devices, other types of flash memory, or the like.
For portability, the golf GPS device of the present invention is self-contained, compact and lightweight. For example, the device is preferably battery operated. The portable golf GPS device is preferably contained in a housing such that the entire device has a very compact and lightweight form factor, and is preferably handheld and small enough to fit comfortably in a pocket of a user's clothing. For example, the entire golf GPS device may be 4 inches long (4″), by 2 inches wide (2″), by 0.6 inches thick (0.6″), or smaller in any one or more of the dimensions. The entire golf GPS device may weigh 3.5 ounces or less, including the battery.
The microprocessor may be any suitable processor, such as one of the MX line of processors available from Freescale Semiconductor or other ARM based microprocessor. The GPS unit may be any suitable GPS microchip or chipset, such as the NJ1030/NJ1006 GPS chipset available from Nemerix, Inc. The LCD is preferably a high resolution (e.g. 320 pixels by 240 pixels, QVGA or higher resolution), full color LCD, having a size of about 2.2″ diagonal.
The program memory may include one or more electronic memory devices on the golf GPS device. For example, the program memory may include some memory contained on the microprocessor, memory in a non-volatile memory storage device such as flash memory, EPROM, or EEPROM, memory on a hard disk drive (“hdd”), SD Card(s), USB based memory devices, other types of flash memory, or other suitable storage device. The program memory stores at least some of the software configured to control the operation of the device and provide the functionality of the golf GPS device.
The components of the portable golf GPS device are preferably assembled onto a PCB, along with various other electronic components used to control and distribute the battery power, thereby providing the electronic connections and operability for a functional electronic device.
The hardware and software of the portable golf GPS device are configured to determine, track, and display useful golf related information, before, during and after a round of golf. For example, the GPS device is configured to store golf course data for a particular golf course of interest which is loaded onto the GPS device in any suitable manner. The golf course data includes geographic location coordinates for various golf course features, such as bunkers, greens, water hazards, tees, and the like. The golf course data may also include golf hole data such a par, handicap, daily tee and hole locations, etc. In addition, the golf course data may include photographic course images, such as satellite or aerial photographs and/or video images.
The use of the GPS device during play of a round of golf is referred to herein as “Play Golf” mode. In Play Golf mode, the basic functionality of the device is as follows. First, the golf course being played is selected on the GPS device, for example, from a list of courses displayed on the display. Then, the user should locate the GPS device at a location of play (e.g. the location of the user's ball, or a tee box). The GPS device determines the location of the device, and then displays various golf hole information on the display. For example, the device may display the number of the particular golf hole being played, par for the hole, the length of the hole, and the handicap of the hole. The device may also display information regarding the distance to various features of the golf hole being played and an identification of the type of feature. For example, the display may show the front and carry distance of bunkers, the front, middle and back of the green, the front and carry distance of water hazards, and the like.
In one innovative aspect of the present invention, the GPS device is configured to display the golf hole information in two distinct operating modes. In a first mode, also referred to herein as the Basic Mode, the distances and features are displayed in a text and/or icon format. This may be accomplished by simply displaying a list of features and respective distance(s) for each feature, such as “Right Fairway Bunker . . . 245-275” or an icon representing a fairway bunker next to the distance “ . . . 245-275.” This would indicate that there is a fairway bunker on the right, and is 245 yards to reach the bunker and 275 yards to carry the bunker. In a second mode, also referred to herein as the Pro Mode, the distances and features are shown on the display on a graphical image of a relevant area (also referred to as a “viewport”) of the golf course. The graphical image is preferably a photographic image generated from geo-referenced (e.g. coordinates are available for any location on the image) satellite or aerial digital photographs, or geo-referenced generated images. Thus, the images of the features, such as bunkers, the green, water hazards, etc. are displayed in the photographic image and the distances are overlaid onto the image. In another feature of the present invention, a distance marker, such as a red dot or other small but easily viewable symbol, is placed on the feature at the exact point of measurement, and the distance number is displayed in the vicinity of the marker.
If the Pro Mode course data has been loaded onto the device, the device is configured such that it can toggle back and forth between the Pro Mode display and the Basic Mode display. However, if only the Basic Mode course data has been loaded onto the device, only the Basic Mode information may be displayed. While viewing a list of features in Basic Mode, a feature may be selected, such as by scrolling through the list of features, and the user may select to view the Pro Mode display of such feature simply by selecting the feature from the list and selecting the Pro Mode. Of course, this feature would only be available if the Pro Mode course data has been loaded onto the device. The golf course data set required to operate the device in the Pro Mode and the Basic Mode is the same, except that the Pro Mode data set includes the graphical images of the golf course. This simplifies the creation of the course databases because creation of the Pro Mode data set also creates the Basic Mode data set.
In another aspect of the present invention, the device includes an innovative automatic, dynamic, viewport generation method for optimizing the viewability of the distance and feature images in the Pro Mode. The viewport generation may include one or more of several methods to determine the displayed viewport. In one example, the viewport generation method may include a method of determining the location and scale of the image of the golf course to be displayed based on the location of the device (and therefore the location of play) and the characteristics of the golf hole. As an example, the method of viewport generation method may display a section of the golf hole that will be most relevant to the golfer from the current location, which may be a yardage range such as the next 150 to 250 yards of the golf hole. The method will automatically scale (i.e. set the zoom level) the graphic image of the relevant section of the hole so that it will fit on the display while maintaining viewability of relevant features (e.g. bunkers, the green, hazards) and informational text (e.g. yardages). If the hole happens to be a par 3, or there is less than a certain distance (e.g. 250 yards) to the end of the hole, then the viewport generation method may display the rest of the hole at a maximum zoom level that can fit the rest of the hole on the display.
In another method of viewport generation, the distances displayed may be adjusted to avoid overlapping. This method may also be referred to as collision management. At certain zoom levels, for example very low zoom levels, many features as displayed on the display may be very close together such that if all of the distances to these features are displayed the numbers will overlap and the readability of the information will be compromised. To avoid this, the method will not display some of the distances so as to avoid any overlapping distances.
In another aspect of the present invention, the GPS device is configured to provide panning and zooming of the displayed graphical images of the golf course with the distance overlays. In other words, when viewing any Pro Mode graphical display with distances overlaid onto features, the device is configured so that the user can pan the image to display the golf course outside the original viewport, and the distances remain overlaid at the correct locations next to their respective features. Similarly, when zooming in or out from a particular viewport, the distances again remain overlaid at the correct locations next to their respective features (or feature marker). In addition, when zooming and panning, the font size of the distances may be constant or set to display at a minimum font size, and the collision management methods described above may also be utilized.
In still another aspect of the present invention, the golf GPS device is configured to allow the measurement of the distance between locations on the golf course using the images displayed on the display. This is a useful feature which is enabled by the use and display of the actual photographic images of the golf course, and is very simple to use. For example, to measure the distance between the current location of the device and another location of interest as displayed on the display, the user simply selects the measurement mode, moves a cursor displayed on the display to the location of interest and then selects the location of interest. The device is configured to determine and display the distance between the coordinates of the current location of the device and the location of interest. In a similar manner, the device may also be configured to measure the distance between two locations of interest selected on display. In addition, the pan and zoom functions may be utilized automatically or manually during the measurement mode in order to select a location of interest. In other words, as the cursor reaches the edge of the viewing area, the image will pan to display a portion of the image that was previously outside the viewing area.
In yet another aspect of the present invention, the device is configured to perform an innovative calibration method. Like the measurement mode, this feature is enabled by the use and display of the actual photographic images of the golf course. To utilize this feature, the user locates a physical feature at the golf course which can also be fairly accurately identified and located on a graphical image of the same physical feature shown on the display of the GPS device. Several examples of good features for this calibration method are a cart path intersection, a distinctive shape of a bunker, a manhole cover, or a permanent tee marker. The device is then placed at the physical feature, and then the user places a cursor shown on the display of the device onto the image of the same physical feature. To improve the precision of the location of the cursor, the image of the feature may be zoomed in to a high zoom level or even the maximum zoom level. The device is configured to determine the offset between the apparent location measured by the GPS device and the location of the physical feature on the displayed image. The resultant offset may then be used to correct all future GPS readings. The positional errors in GPS due to pseudo-range errors in the GPS satellite system and environmental conditions are approximately equal within the period of time of a round of golf and over the area of a single golf course. Thus, a single calibration during a round of golf will usually be sufficient to account for inaccuracies due to environmental conditions and pseudo-range errors of GPS satellite system. Still, multiple calibrations during a single round of golf may be accomplished, if desired.
The GPS golf device of the present invention may also be configured to present a pre-round preview of a golf course, including a display of each hypothetical shot and/or suggested strategy. This allows the user to get a visual experience and strategize the course prior to playing.
Similarly, the device may be configured to track each shot during a round of golf, including the club used for each shot and other shot information (such as quality and condition of lie, degree of swing such as full shot, half shot, etc., quality of contact, ball flight, etc.). The device may also be configured to play back a round of golf which was tracked using the device, and/or download the tracked round to a computer or other device for playback and/or analysis.
In still another feature of the present invention, the golf GPS device may include voice recognition/navigation. The golf GPS device may be configured to allow a user to enter information using vocal inputs, such as shot information and scores. The voice recognition feature may also be used to audibly enter commands, such as switching between Basic Mode and Pro Mode, navigating through the devices menus, changing the settings, or any other command within the devices menus. Voice recognition facilitates the use of more advanced features, such as shot tracking, by reducing the amount of inputs that must be made using the input device. As an example, when entering a club selection for shot tracking, instead of having to scroll through a list of clubs, the user need only say “seven iron” or “driver.”
Accordingly, a portable golf GPS device and system is provided. Additional aspects and features of the portable golf GPS device and system of the present invention will become apparent from the drawings and detailed description provided below.
FIG. 1
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Referring to , a schematic block diagram of the major electronic components of a golf GPS device according to one embodiment of the present invention will be described. The golf GPS device comprises a microprocessor which is operably coupled to a GPS chipset , a user input device , an LCD display ; a program memory , a voice recognition module , an audio output , a data transfer interface , and a battery and power management unit . As understood by one of ordinary skill in the art, the device also comprises other electronic components, such as passive electronics and other electronics configured to produce a fully functional GPS device as described herein. In addition, the device comprises various firmware and software configured to control the operation of the device and provide the device functionality as described in more detail below.
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The microprocessor is preferably an ARM based microprocessor, such as one of the MX line of processors available from Freescale Semiconductor, but may be any other suitable processor. The microprocessor executes instructions retrieved from the program memory , receives and transmits data, and generally manages the overall operation of the GPS device .
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The GPS chipset is preferably an integrated circuit based GPS chipset which includes a receiver and microcontroller. The GPS chipset may be a single, integrated microchip, or multiple microchips such as a processor and a separate receiver which are operably coupled to each other (for example, on a printed circuit board (“PCB”)). For instance, the GPS chipset may be a NJ1030 GPS chipset available from Nemerix, Inc., or any other suitable GPS chipset or microchip. The GPS chipset includes a GPS receiver, associated integrated circuit(s), firmware and/or software to control the operation of the microchip, and may also include one or more correction signal receiver(s) (alternatively, the correction signal receiver(s) may be integrated into a single receiver along with the GPS receiver). As is well known, the GPS unit receives signals from GPS satellites and/or other signals such as correction signals, and calculates the positional coordinates of the GPS unit . The GPS device utilizes this positional data to calculate and display distances to features or selected locations on a golf course, as described in more detail below.
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The display may be any suitable graphic display, but is preferably a high resolution (e.g. 320 pixels by 240 pixels, QVGA or higher resolution), full color LCD. The display is preferably the largest size display that can be fit into the form factor of the overall device , and preferably has a diagonal screen dimension of between about 1.5 inches and 4 inches. For example, for the form factor described below with reference to , the display may be a 2.2″ diagonal, QVGA, full color LCD. In addition, since the display is intended to be used outside under sunlit conditions, the display should provide good visibility under brightly lit conditions, such as with a transflective LCD.
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The program memory stores at least some of the software and data used to control and operate the device . For example, the program memory may store the operating system (such as LINUX or Windows CE), the application software (which provides the specific functionality of the device , as described below), and the golf course data. The program memory broadly includes all of the memory of the device , including memory contained on the microprocessor, memory in a non-volatile memory storage device such as flash memory, EPROM, or EEPROM, memory on a hard disk drive (“hdd”), SD Card(s), USB based memory devices, other types of flash memory, or other suitable storage device, including one or more electronic memory devices on the golf GPS device, including an additional removable memory unit .
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The user input device may comprise a plurality of buttons, a touch screen, a keypad, or any other suitable user interface which allows a user to select functions and move a cursor. Referring to the embodiment shown in , an example of a user input device comprises a directional pad and plurality of buttons , , , and . The device is configured such that directional pad may be used to move a cursor around the display, while the buttons -may be used to make selections and/or activate functions such as activating the voice recognition or switching between modes (as described in more detail below).
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In order to provide portability, the golf GPS device is preferably battery powered by a battery and power management unit . The battery may be any suitable battery, including one or more non-rechargeable batteries or rechargeable batteries. For instance, a rechargeable, lithium-ion battery would work quite well in this application, as it provides relatively long life on a single charge, it is compact, and it can be re-charged many times before it fails or loses significant capacity. The power management unit controls and distributes the battery power to the other components of the device , controls battery charging, and may provide an output representing the battery life. The power management unit may be a separate integrated circuit and firmware, or it may be integrated with the microprocessor , or other of the electronic components of the device .
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The voice recognition unit comprises electronics and software (the term “software” as used herein shall mean either software or firmware, or any combination of both software and firmware) configured to receive voice or other sounds and convert them into software commands and/or inputs usable by the main application software. The voice recognition unit may comprise a separate integrated circuit, electronics and/or software, or it may be integrated into the main microprocessor . The voice recognition unit includes a microphone . The voice recognition unit is configured to detect voice and/or other sound inputs from a user of the device , and convert the sound inputs into electrical signals. The voice recognition unit then digitizes the analog electrical signals and computes a command or other input representative of the digitized signal. For example, a command for switching between Pro Mode and Basic Mode may be input using the voice recognition unit by speaking the term “Pro Mode” or “Basic Mode” into the microphone . Of course, the main application software must also be configured to receive the inputs from the voice recognition unit . The hardware and software for the voice recognition unit are relatively complex, but packaged solutions are available, such as the products available from Texas Instruments, Inc. or Wolfson Micro, Inc.
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The audio output comprises electronics and software to convert digital signals from the device into electrical signals for driving a speaker or headphones. The audio output may comprise a phone jack (also shown in ) and/or a speaker . The audio output typically includes a digital-to-analog converter, a power amplifier, and may also include software for converting information or data into audible sounds. For instance, the audio output may be configured to convert distances measured by the device into an audibly replicated voice of the distance in words, such as “one-hundred fifty.” Additionally, the device may be configured to also play digital music files (such as MP3 audio files) or digital video files (such as MPEG files), with the audio being output using the audio output .
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The voice recognition unit and audio output may be integrated together into a software and hardware unit. For example, such integrated products are available from Texas Instruments, Inc. and Wolfson Micro, Inc.
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The data transfer interface is configured to send and receive data from a computer or other electronic device (e.g. another golf GPS device ). The interface may be a physical connection such as a USB connection, a radio frequency connection such as Wi-Fi, wireless USB, or Bluetooth, an infra-red optical link, or any other suitable interface which can exchange electronic data between the GPS device and another electronic device. As shown in one preferred embodiment in , the interface comprises a USB connection having a USB connector
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The electronic components of the golf GPS device are preferably assembled onto a PCB, along with various other electronic components and mechanical interfaces (such as buttons for the user input device ), thereby providing the electronic connections and operability for a functional electronic GPS device .
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Turning to now, the golf GPS device preferably comprises a housing which houses the electronic components such that the entire device has a very compact, thin, and lightweight form factor. The housing may be formed of any suitable material, but is preferably a plastic material which is substantially transparent to radio frequency signals from GPS satellites. Indeed, the golf GPS device is preferably handheld and small enough to fit comfortably in a pocket of a user's clothing. One example of the form factor for the GPS device with dimensions is shown in . In one preferred form, the GPS device may have the following dimensions: a height of about 4 inches or less, a width of 1.9 inches or less and a thickness of 0.6 inches or less. More preferably, the height is 3.9 inches or less, the width is 1.8 inches or less, and the thickness is 0.55 inches or less. The entire golf GPS device may weigh about 3.5 ounces or less, including the battery .
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An application software program is stored in the program memory . The application software program is configured to operate with the microprocessor and the other electronic components to provide the golf GPS device with the functionality as described herein. Most generally, the hardware and software of the portable golf GPS device are configured to determine, track, and display useful golf related information, before, during and after a round of golf. The GPS device is configured to store golf course data for a particular golf course of interest which is loaded onto the GPS device through the data transfer interface .
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The golf courses are mapped to create the golf course data using any suitable method, such as ground survey, or more preferably, by using geo-referenced satellite or aerial images. The mapping process produces golf course data which can be used by the GPS device to determine the coordinates of golf course features of interest, such as the greens, bunkers, hazards, tees, pin positions, other landmarks, and the like. Generally, the perimeter of the golf course features will be mapped so that distance to the front and back of the feature may be determined. The mapping process can be done quickly and easily by displaying the geo-referenced images of the golf course on a computer and then using a script (or other software) each feature of interest is traced (or a series of discrete points on the perimeter may be selected). The captured data is then used to create a data set comprising the coordinates for a plurality of points on the perimeter of the feature, or a vector-map of the perimeter, or other data, which can be used to calculate the distance to such feature from the location of the GPS device . The golf course data preferably also includes golf hole data such as par, handicap, daily tee and hole locations, etc. In addition, for use with the “Pro Mode” as described below, the golf course data may include geo-referenced photographic course images, such as satellite or aerial photographs and/or video images. Indeed, the golf course data package for operating the device in the Pro Mode and the Basic Mode is substantially the same, except that the Pro Mode data package includes the graphical images of the golf course. In other words, the golf course data related to the feature locations is exactly the same for both the Pro Mode and the Basic Mode, and the GPS device is configured to utilize this data with or without the graphical images. Thus, advantageously, creation of the Pro Mode data package also creates the Basic Mode data set.
FIGS. 3-11
FIG. 3
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With reference now to , the operation and functionality of GPS device according to one embodiment will be described. Referring to , a “Main Menu” screen is displayed on the display . The “Main Menu” screen has two options, “Play Golf” or “Settings.” The choices on the Main Menu screen (or any of the other menus and screen displays described herein) can be selected by changing the highlighted option using the up and down arrows on the directional pad of the user input device . The button may function as an “Enter” key to make a selection. If a touch screen input device is utilized, the user can simply touch the selection on the display .
Selecting “Settings” will bring up a “Settings” menu which allows the user to set various device and player settings and preferences. For example, the “Settings” menu may allow the user to set such user preferences as system units (e.g. yards or meters), preferred display settings (e.g. text size, Pro Mode vs. Basic Mode, screen brightness and contrast), turning on/off functions (such as score keeping, voice recognition, shot tracking, etc.), and other device settings.
FIG. 4
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Selecting the “Play Golf” mode brings up a “Golf Menu” as shown in for initializing the GPS device for use during a round of golf. The course being played may be selected by selecting “Select Course” which may bring up a list of courses currently stored on the device . The list of courses shown can be determined based on the location of the device as determined by the GPS device , for example, a list of the two or three courses closest to the location of the device. Alternatively, the list can be generated as a simple alphabetical list, a list of favorites, or other suitable listing method. The “Golf Menu” also allows the user to choose the starting hole, for instance, if a player is going to start on a hole other than the 1st hole, such as starting on the 10th hole (the “back nine”).
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FIG. 5
Once the course and starting hole have been selected, GPS device determines the location of the device using the GPS chipset , and then displays various golf hole information on the display. Turning to , in this described embodiment, the GPS device is configured to display the hole number , the current time (the device may include a clock function which can be provided by the microprocessor , the GPS chipset , or other electronic device), the par for the hole , a battery charge indicator , and a GPS signal strength indicator . The GPS device further calculates the distance between the determined location of the device and the front, middle and back of the green and displays the distance to the front , the middle and the back of the green. As the device is moved, the location of the device is continually updated, and the distances (such as the front , middle , and back of green) displayed are updated accordingly.
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The GPS device may also be configured to display a video flyover of the hole being played using a satellite or aerial photographic images of the hole. The GPS device may be configured to automatically display the flyover when the device detects that the GPS device is approaching or has reached a particular hole, and/or the user can select to display the flyover using the menu-driven selections.
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FIG. 6
FIG. 5
FIG. 6
FIG. 6
FIG. 6
d
The golf GPS device also may display the distances from the location of the device to hazards and other features of interest as shown in . As an example, the user may select the “Hazard” selection on the display shown in using the button to bring up the screen as shown in . The screen shown in displays the “Hazard” information in what is referred to herein as “Basic Mode.” Basic Mode displays the “Hazard” information in a list using icons or text and respective measured distances. The example of shows an icon for a right fairway bunker and the distance to the front side of the bunker is 248 yards and the distance to carry the bunker is 264 yards. Similarly, the screen shows that the distance to the left greenside bunker is 455 yards to reach and 472 yards to carry. Instead of easy to read icons, the features can alternatively be displayed using text, such as “Right Fairway Bunker” or using an abbreviation such as RtFwyBnkr, or the like.
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FIGS. 7 and 8
FIG. 7
FIG. 6
FIG. 8
As described above, the GPS device may be configured to display the golf hole information in two distinct operating modes. The first mode is the Basic Mode which displays the distances and features in a text and/or icon format. In the second mode, referred to herein as the Pro Mode, the distances and features are shown on the display on a graphical image of a relevant area (also referred to as a “viewport”) of the golf course. Examples of the Pro Mode showing the same information as the display shown in are shown in . The graphical image is preferably a photographic image generated from geo-referenced (e.g. coordinates are available for substantially any location on the image) satellite or aerial digital photographs, or geo-referenced, generated images. In Pro Mode, the images of the features, such as bunkers, the green, water hazards, etc. are displayed in the photographic image and the distances are overlaid onto the image. A distance marker , such as a red dot or other small but easily viewable symbol, is placed on the feature at the exact point of measurement, and the distance number is displayed in close proximity to the marker . Referring to the example of , the right fairway bunker is 248 yards to reach and 264 yards to carry. This is exactly the same distance information shown in the display depicted in . Likewise, as shown in , the left greenside bunker is 455 yards to the front and 472 yards to the back.
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As explained above, the golf course data for both the Pro Mode and the Basic Mode is the same, except that the golf course images are required for the Pro Mode. Thus, if the Pro Mode course data has been loaded onto the device, the device is configured such that it can toggle back and forth between the Pro Mode display and the Basic Mode display. One of the buttons, such as button or (see ), may be set up to toggle between the Pro Mode and the Basic Mode. However, if only the Basic Mode course data has been loaded onto the device, only the Basic Mode information may be displayed.
FIG. 6
While viewing a list of features in Basic Mode, a feature may be selected, such as by scrolling through the list of features as shown in , and the user may select to view the Pro Mode display of such feature simply by selecting the feature from the list and selecting the Pro Mode. Of course, this feature would only be available if the Pro Mode course data has been loaded onto the device.
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In order to optimize the viewability of the golf course images and displayed distances in the Pro Mode on a relatively small display , the golf GPS device may include a automatic, dynamic, viewport generation method. The ability to miniaturize the size of the device is in many ways limited by the size of the display , the major tradeoff being the desire to maximize the size of the display in order to be able to display as much information and images at an easily viewable scale, while at the same time keeping the overall size of the device as small as possible. Intelligent generation of the of the images and numbers being displayed can help to display the most relevant section of the golf hole being played with distances displayed at a font size that is easily readable.
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The viewport generation may include one or more methods to determine the displayed viewport. First, the viewport generation method may include a method of determining the location and scale of the image of the golf course to be displayed based on the location of the device (and therefore the location of play) and the characteristics of the golf hole. For example, the method of viewport generation method displays the section of the golf hole that will be most relevant to the golfer from the current location, which may be a yardage range such as the fairway which is between 150 and 250 yards from the current location. As one specific example, shows a viewport which might be displayed if the user is on the tee box of the displayed hole. The viewport displays the fairway and area surrounding the fairway from about 200 yards to 375 yards from the tee. The graphic image is automatically scaled (i.e. the zoom level is set) to display the relevant section of the hole so that it will fit on the display while maintaining viewability of relevant features (e.g. the bunkers) and distance to the fairway bunker. If the hole happens to be a par 3, or there is less than a certain distance (e.g. 250 yards) to the end of the hole, then the viewport generation method may display the rest of the hole at a maximum zoom level that can fit the rest of the hole on the display (see e.g. ).
In another method of viewport generation, the distances displayed may be adjusted to avoid overlapping. This method may also be referred to as collision management. At certain zoom levels, for example very low zoom levels, many features as displayed on the display may be very close together such that if all of the distances to these features are displayed the numbers will overlap and the readability of the information will be compromised. To avoid this, the method will not display some of the distances so as to avoid any overlapping distances. The determination of the distances which will not be displayed, so as to avoid overlap, may be determined based on a hierarchy of the features, a random determination, a predetermination contained in the course data, an algorithm which determines the most important distances, some other criteria, or a combination of these methods. In another aspect of this feature, the method can be configured such that the user may select to display some or all of the non-displayed distances in which case the previously displayed distances which overlap these non-displayed distances are turned off. This selection may be a toggle, so that the user can toggle back and forth between the distances displayed. If there are more than two distances which would conflict with each other if displayed simultaneously, this user selection can advance through each of the non-displayed distances until all of the distances can be displayed sequentially, while the other conflicting distances are turned off.
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The GPS device may also pan and zoom the displayed graphical images of the golf course with the distance overlays in Pro Mode. Referring to , an example of a green view at a low zoom level is shown. The device is shown in “Zoom” mode which is indicated by the “Zoom/Pan” toggle selection at the bottom left corner of the display . To zoom “in” on the image being displayed, the “up” arrow on the directional pad is pushed, as shown in . To zoom “out”, the “down” arrow on the directional pad is pushed. The device may be configured such that holding down the “up” or “down” arrow will continue to zoom “in” or “out,” respectively. To switch to “Pan” mode as shown in , the button is pushed. The user can pan the displayed image by pressing the desired direction of pan on the directional pad . When zooming or panning, the distances again remain overlaid at the correct locations next to their respective features (or feature marker) and at the pre-set font size.
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The golf GPS device may also be configured to measure the distance between locations on the golf course using the images displayed on the display. In order to measure a distance from the location of the device to a location as viewed on image on the display, the “Meas” button is selected (see ), to enter “Measure” mode as shown in . A cursor (such as a “+”) and a marker (such as the star shown in ) will appear at the current location of the device . The marker indicates the current location of the device , and the cursor indicates the point being measured to. At the outset, the marker and cursor are at the same location, so the distance is displayed as “0”. The directional pad is then used to move the cursor to the location of interest. As the cursor is moved, the distance between the cursor and the marker is calculated and displayed. As the cursor reaches the edge of the display in the direction of interest, the display may automatically pan (and/or zoom), as shown in . When the cursor is located at the location of interest, the desired distance will be displayed, as shown in the example of . In a similar manner, the device may also be configured to measure the distance between two locations of interest selected on display. The user simply selects the “Meas” mode. The cursor is then positioned at a first point of interest, the button is pushed to set the first point of interest, and then the cursor is moved to a second point of interest. As in the example above, the distance between selected first point of interest and the location of the cursor will be updated and displayed as the cursor is moved. The distance between a first location for the device and a second location of the device may also be measured by simply entering the “Meas” mode and then moving the device to a new location. As the device is moved, the distance between the original location of the device and the new location of the device will be calculated and displayed. The pan and zoom functions may be utilized automatically or manually during any of the above described measurement modes in order to select a location of interest. In other words, as the cursor reaches the edge of the viewing area, the image will pan (and/or zoom “out”) to display a portion of the image that was previously outside the viewing area.
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In order to improve the accuracy of the device, the golf GPS device also includes a calibration method which corrects for local errors in the GPS system. Because the golf course images utilized on the device are accurately geo-referenced with global coordinates, every discernable feature on the golf course images is a potential calibration point. To perform the calibration, referring to , the “Calibrate GPS” mode is selected. The use then locates a physical feature at the golf course which can also be fairly accurately identified and located on a graphical image of the same physical feature shown on the display of the GPS device . As examples, the calibration feature may be a cart path intersection, a distinctive shape of a bunker, a manhole cover, or a permanent tee marker. The GPS device is then placed at the physical feature, and then the user places a cursor shown on the display of the device onto the image of the same physical feature. It may be helpful to zoom in to a high zoom level or even the maximum zoom level of the physical feature to improve the precision of the location of the cursor. The device then determines the offset between the apparent location measured by the GPS device and the location of the physical feature on the displayed image. The resultant offset is then used to correct all the GPS readings for the round of golf.
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The golf GPS device of the present invention may also be configured to present a pre-round preview of a golf course. The golf GPS device allows the user the load a desired golf course and then navigate around the course, such as hole by hole. The preview may include a display of each hypothetical shot which might be take for each hole and/or suggested strategy for playing each hole and/or shot. For instance, the preview mode may display pre-loaded hypothetical shots which are automatically generated or contained within a golf course data package; or the preview mode may use distances typical of the user's club distances, or a distance as selected by the user for each shot, to perform a shot-by-shot preview. A golf game may be implemented on the golf GPS device , in which the user can play a game of golf on the desired golf course, similar to other golf video games like “Tiger Woods PGA Tour” or “Mario Golf”, in which the game will be played on the actual golf course images stored on the device .
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Similar to the pre-round preview feature, the golf GPS device may be configured to track each shot taken by the user during a round of golf, including the club used for each shot and other shot information (such as quality and condition of lie, degree of swing such as full shot, half shot, etc., quality of contact, ball flight, etc.). At each ball position during a round of golf, the device is configured to receive an input of the shot information and store the shot information referenced to the location of the device . With this stored information, the device may also be configured to play back a round of golf which was tracked using the device, and/or download the tracked round to a computer or other device for playback and/or analysis.
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In order to facilitate the entry of commands and information into the device, the golf GPS device may include voice recognition/navigation utilizing the voice recognition unit . Indeed, voice recognition for inputting commands and information can be absolutely critical in enabling the timely use of many advanced features, such as shot tracking and score keeping, for example. Without voice recognition, such advanced features would be far too cumbersome and time consuming on a golf course. Moreover, voice recognition also enables the small form factor of the present invention because it avoids the need for a larger, more complicated input device, which might otherwise be necessary to quickly access and use certain advanced functions. For instance, additional input buttons and/or menus may be required to provide fast and easy use of advanced features which can have many options and/or possible input data.
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Several examples of the use of the voice recognition capability follow. The golf GPS device may be configured to allow a user to enter shot information while using the shot tracking mode using vocal inputs, or to enter scores on each hole. For instance, when entering a club selection for shot tracking, the user simply enters the voice mode and speaks into the device, “seven iron” or “driver”, or whatever club is being used. For score keeping, the device can be configured to recognize a player's name vocally input into the device, and then the score for a hole for such player. Thus, a user need only activate the voice recognition, then state the player's name and score in order to input the score for a player (e.g. “John, six;” Jerry, four”). The device determines the name and score from the voice input, and then stores the data. The score data can then be displayed on the display . The voice recognition feature may also be used to audibly enter commands, such as switching between Basic Mode and Pro Mode, navigating through the devices menus, changing the settings, or any other command within the devices menus. Voice recognition facilitates the use of more advanced features, such as shot tracking, by reducing the amount of inputs that must be made using the input device. The use of voice recognition can also allow faster, and simpler access to certain commands/functions by bypassing menus that might normally be encountered when accessing such commands/functions. For example, a screen brightness setting might require going to the “Settings” menu, and then a submenu for “Display” settings, and then a selection of a “Screen Brightness” setting. Instead, the device may be configured to recognize a voice command, such as “Screen Brightness” spoken into the device , in which case the device will skip directly to the “Screen Brightness” setting. Of course, the device could be configured to directly perform any of the functions of the device using a voice command.
The golf GPS device of the present invention may include any one or more of the features and functions described above, or any combination of such features and functions which are not by their nature mutually exclusive.
The foregoing illustrated and described embodiments of the invention are susceptible to various modifications and alternative forms, and it should be understood that the invention generally, as well as the specific embodiments described herein, are not limited to the particular forms or methods disclosed, but also cover all modifications, equivalents and alternatives falling within the scope of the appended claims. The invention, therefore, should not be limited, except to the following claims, and their equivalents.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a schematic block diagram of a golf GPS device according to one embodiment of the present invention.
FIG. 2
is a four view showing the front, left side, right side, top and bottom of a golf GPS device according to one embodiment of the present invention.
FIG. 3
is front, elevational view of a GPS device with a Main Menu displayed on the display according to one embodiment of the present invention.
FIG. 4
is front, elevational view of a GPS device with a Golf Menu displayed on the display according to one embodiment of the present invention.
FIG. 5
is front, elevational view of a GPS device with golf hole information displayed on the display according to one embodiment of the present invention.
FIG. 6
is front, elevational view of a GPS device with a Hazard view in Basic Mode displayed on the display according to one embodiment of the present invention.
FIG. 7
is front, elevational view of a GPS device with a Pro Mode view displayed on the display according to one embodiment of the present invention.
FIG. 8
is front, elevational view of a GPS device with another Pro Mode view displayed on the display according to one embodiment of the present invention.
FIG. 9
is front, elevational view of a GPS device with a zoomed in Pro Mode view displayed on the display according to one embodiment of the present invention.
FIG. 10
is front, elevational view of a GPS device in a Measure mode displayed on the display according to one embodiment of the present invention.
FIG. 11
is front, elevational view of a GPS device with another aspect of the Measure mode displayed on the display according to one embodiment of the present invention. | |
I’ve been curious about how much of scholarship is now open access, but recent news of universities such as Harvard and UC San Francisco requiring faculty to either publish in open access (OA) journals or post their work in publicly accessible repositories prompted me to want to undergo a more serious examination of this question.
There are three main quantitative measures researchers use to answer this question:
- the percentage of all scholarly journals that are OA
- the percentage of all scholarly articles published per year that are OA
- the percentage of all scholarly articles in important scholarship indexes that are to OA articles
Let’s address each of these in turn, and then I’ll conclude with implications for what OA will look like in 10 years
The percentage of all scholarly journals that are OA
A study by Bo-Chister Björk and colleagues finds that in 2009 there were 4,769 OA journals with an 18% yearly growth rate from 1993 to 2009. The directory of open access journals (DOAJ) now lists 7787 OA journals, out of a universe of approximately 26,000 scholarly journals total (calculated using Heather Morrison’s methodology), so somewhere between 24% and 29% of all journals are open access. An important note is that while there are thousands of OA journals, they constitute less than 24%-29% of all articles published because many OA journals are newer and hence have fewer back issues, and many OA journals publish fewer than average articles per year – which leads us to …
The percentage of all scholarly articles published per year that are OA
Approximately 1.5 million scholarly articles are published per year. Björk and colleagues estimated in 2009 that 7.7% of all articles published were in OA journals. Richard Poydner draws on Björk and Gargouri to conclude that “around 30% of the academic and scientific literature published in 2011 worldwide may now be freely available on the Web, two thirds of it as Green OA and one third of it as Gold OA.” For reference, gold OA generally refers to OA journals while green OA refers to public repositories with either the published article, a pre-print version, or a different post-print version (for more, see Peter Suber’s overview). The Open Access Directory estimates that 94.9% of non-OA journals permit “authors to self-archive their preprints, postprints, or both, according to Eprints statistics.”
The percentage of all scholarly articles in important scholarship indexes that are to OA articles
Indexes such as ISI and SJR are important because they give an indirect measure of how important an individual articles is both within its field and within academia more broadly. Articles that are not indexed are generally not being cited by other scholars and not being published in journals that have other important articles. The question of how much of the indexed scholarship is OA is important for gauging the importance of OA scholarship as well as an indicator of whether OA literature is, on average, as important as non-OA scholarship.
Scholars offer case studies to support OA scholarship, such as the example of the OA journal Cancer Journal for Clinicians, which “is the 4th most heavily cited journal among ALL journals indexed. With 62 citations per article based on SCImago calculations, its articles on average appear to be the most highly cited of any scholarly journal of any kind.” Similarly, PLoS One has been ranked #1 since the first year it was tracked.
From a macro standpoint, a study by Elena Giglia concludes that while the results are mixed, OA journals are competing from a 5-year impact factor standpoint with older journals, and she expects OA journals to gain reputation as they age, and in certain fields such as law open access scholarship is actually more cited than non-OA.
Implications for the next 10 years
Springer offers a projection through 2020 that is revealing. It assumes 3.5% growth of all scholarly articles produced and 20% growth of OA articles, and concludes that it expects about 25% of all articles to be OA in 2020. This is higher than 0.5% annual growth Bjork estimates, which based on OA constituting 7.7% of the article volume for 2009 would only anticipate 13.2% of all articles being OA in 2020.
Another interesting note is that Springer assumes about 4% of articles are OA in 2009, but it we use Björk’s 7.7% number as a starting point with 20% growth per year, by 2020 we would expect 50% of all articles to be OA. And by Springer’s own figures, by 2025 we would expect 60% of all articles to be OA!
I would expect that if the wave of college and university OA mandates continue (there are 148 institutions who have mandates currently) this would accelerate OA publishing, especially if the mandates require publishing in OA journals versus requiring green OA in public repositories.
It’s not clear to me how increased mandates and more OA articles will affect non-OA journal pricing. I could image an overall decreased demand for journals as scholars access articles via searches and aggregators such as Google Scholar, but I can also image scholars still wanting their libraries to purchase access to all scholarship and thus demand remaining steady or even rising as more content is free to paid content becomes even more premium (think the HBO model). Ideally, the price of journals would drop to the point where the value seems more in line with cost – which again points to journals decreasing prices until in line with value: PLoS ONE is an example of OA leading to reduced journal costs, as it costs 1/8 the average journal price.
In summary, conservative figures expect OA publishing to constitute ~15% of published scholarship in the next 10 years, moderate calculations arrive at ~25%, and more hopeful numbers point to potentially 40%-50% of scholarship being OA in 10 years. I’m excited that Scholastica is rolling out an OA publishing solution that builds on our peer review functionality, and I’m excited to be part of the OA future. | https://blog.scholasticahq.com/post/what-will-open-access-look-like-10-years-from-now/ |
Time Management: Are You Making These 3 Major Time Management Mistakes?
Author : Nickolove Lovemore
Submitted : 2008-10-20 00:00:00 Word Count : 843 Popularity: 246
Tags: time management, increase productivity, increase profitability, achieve more in less time
Time management is becoming an ever increasing concern for business owners and entrepreneurs today. Even employees are increasing feeling the strain because as a result of down-sizing and lay-offs people are expected to achieve more in less time.
However, because of poor time management skills, business owners, entrepreneurs and employees are falling far short of what they could and should be accomplishing. This reduced productivity leads to increased stress and massive loss in profits.
Good time management can result in the success of a business. Poor time management can not only result in poor performance, it can result in the overall failure of a business.
Thomas Edison said:
"Time is really the only capital that any human being has, and the only thing he can't afford to lose."
He was right.
The 3 major mistakes in time management that many people fall victim to are as follows:
1. Multi-Tasking
Many people are proud multi-taskers but studies have proven that multi-tasking is inefficient.
When you split your focus across many projects nothing benefits from your full undivided attention. Consequently:
~ You make more mistakes.
~ It takes you longer to complete a particular task.
~ It takes you longer to see the fruits of your labour.
It is more effective to prioritise your projects and set aside a dedicated block of time to work solely on that project. Naturally, there are some projects which you won't be able to complete in one sitting. Practice using flowcharts to break down your project and divide each project into smaller discrete blocks of tasks that can be completed in a few dedicated hours.
Focusing all of your mental resources on a particular task may be challenging at first but with practice it will become easier. When you develop your laser focus you will develop flow. And, when you're working in flow you will b able to complete tasks in record time and vastly increase your productivity.
2. Distractions and Interruptions
These come in all guises. To name just a few culprits there's the
~ Telephone
~ Fax
~ Email
~ Newspapers
~ Television
~ Post
~ Social Media sites, e.g. Twitter, Facebook
Yet, generally these are things we can control. We can switch off the telephone. We can hire someone to deal with phone calls and open the post. We can set aside discrete periods of the day, ideally when our energy levels are naturally low, to check email.
We can allocate a set amount of time to participate on Social Media Sites. We can also automate or outsource certain aspects of this. Sites such as Facebook, Twitter and LinkedIn can be valuable for networking, lead generation, promotion, etc. but only if we have a Social Media strategy. You also need to limit the amount of time you speed on these sites or else you can simply end up wasting your time.
Whenever, we are interrupted it can take up to 20 minutes for our full attention to be restored. Often, during this time we may be interrupted yet again which only compounds the negative effect interruptions have on our productivity.
Hence to become more productive it is essential that you learn how to eliminate distractions and interruptions in your working life. You also need to respect other people's time and stop unnecessarily interrupting and distracting others.
3. Fragmented Working Pattern
This is when you start a project for a few minutes and the turn to something else, then go back to the originally project and so on. This is another way to get nowhere fast.
You achieve MAXIMUM effectiveness and productivity when you focus on one thing. This is one reason why meditation is such a valuable tool in helping individuals improve their personal effectiveness. Also, when you think about it, applying your full attention to a particular task is in itself a form of meditation.
The other downside to working in a fragmented, haphazard fashion is that you end up expending far more energy. The result is that at the end of your working day you'll not only wind up achieving less than you had hoped for but you will feel more fatigued and more stressed.
The key is clearly to prioritise the tasks that you need to achieve. Work on the tasks that will result in creating the greatest value first. An important consideration is that what constitutes value is not what you consider to be of value. It is what your clients and customers consider to be of value. In other words, if a particular task results directly or indirectly in generating income for your business and company then this is a task worthy of the investment of your time.
Author's Resource Box
For a FREE video with more expert time management tips to dramatically increase your productivity visit: http://www.MaximiseYourProductivity.com. And for details on a powerful teleseminar series featuring 10 of the worlds leading experts on time management visit Time Management Telesummit
Article Source: | http://www.1articleworld.com/Article/403752/Time-Management-Are-You-Making-These-3-Major-Time-Management-Mistakes.html |
Claiming it will make a great novel, Roc offers to pay Harley and Cyrus for their story. As they talk, the waitress advises Harley and Cyrus that their credit cards don't work.
Cyrus gets a friend in the banking industry to check Harley's credit record and discovers it's terrible.
Harley assures Gus that she's very happy. Pushed by the doctor, Mallet encourages a feverish Marina to fight to get better. Delirious, she calls him Cyrus and kisses him.
Gus pushes Rafe to be there for Natalia, warning that she needs his support right now.
Explaining why she wants her to spend more time with Emma, Olivia advises Ava that it's time the girl start viewing Ava as a mother figure. Ava is reluctant to do so. Later, Olivia asks Natalia to free Gus from his commitment so that she can have him in her final days. Natalia refuses.
Gus asks Ava to sign the legal papers that transfer custody of Emma to her once Olivia is dead. Afterwards, admitting he can't give Natalia what she wants, Gus kisses Olivia passionately.
Thanks to a phony driver's license, Daisy gets approval for an apartment and boasts of her success to Rafe. She claims she'll get the money for the deposit by lying to her mother about needing cash for a class trip.
After Harley turns her down, Daisy lays into her mother for spending all her money on Cyrus. When her friend Jamie admires her fake ID and offers her $100 for one of his own, Daisy decides to go into business.
Mallet forces Cyrus to visit Marina in hopes of helping her feel better.
Harley asks Mallet about throwing some work her way but when he claims he has no interest in helping her, she accuses him of stealing her brother's job. Cyrus sells his watch so he and Harley can have a nice dinner.
What happens next? Find out in our Guiding Light spoilers ...
- Show:
- Guiding Light
- Season:
- Guiding Light Season 56
- Episode Number: | http://plus.tvfanatic.com/shows/guiding-light/episodes/season-56/march-24-2008/ |
12-year-old white-hat hacker is working to save the internet
Cyber criminals use the internet against us to steal money from banks, trick us to steal our data, spy on us, and infect our systems with malicious software.
Author:
Art Holliday
Published:
5:35 PM CST November 27, 2018
Updated:
6:58 PM CST November 27, 2018
One is a former Secret Service agent while the other is a 7th grader who has a black belt in Kung Fu. What Ron Green and Reuben Paul have in common is figuring out ways to make the internet safer for all of us who depend on it.
Recently, 12-year-old Reuben Paul of Austin, Texas, came to St. Louis as the keynote speaker for STLCybercon, an internet security conference at the University of Missouri-St. Louis. Paul is a hacker but not in the negative connotation. He’s a white hat, a good hacker who uncovers security gaps that leave us vulnerable.
More News
“I once asked my mama ‘what’s the difference between a good hacker and a bad hacker?’ Paul told the audience, “and she said ‘a good hacker always listens to his mama, and a bad hacker doesn’t.'”
Paul’s specialty is household items connected to the internet. For instance, one advantage of having a smart home is the convenience it adds to daily life, like programming security, lighting, heating and air conditioning. The downside?
“This connectivity comes with a cost,” Paul said. “The cost of not having enough controls in them to protect us.”
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One disadvantage of smart systems is they can be vulnerable to hacking, an unintended consequence of the internet that affects people all over the world in a variety of ways. Cybercriminals use the internet against us to steal money from banks, trick us to steal our data, spy on us and infect our systems with malicious software. Cybersecurity is the ultimate game of high stakes Whack-a-mole. While we deal with one internet threat, two more pop up in its place.
“I became a Secret Service agent and I was one of the first agents to work on electronic crimes,” said Ron Green, chief security officer of Mastercard in O'Fallon, Missouri.
Among Green’s duties are overseeing the Fusion Center, a large room where Mastercard employees monitor cyber threats from all over the world.
“Anything that might be of interest to us that might affect the cardholders, or to think about things we can do to make ourselves an even harder target in the future. A lot of that stuff happens right here,” said Green.
Green said there are national security implications when it comes to cybersecurity. Financial institutions, hospitals, and energy plants are all internet-dependent, making them an inviting target for hackers.
“So making sure that the power grids are protected, making sure that financial infrastructure is sound. Making sure the energy that we all depend on the lights, medical equipment in hospitals, that's all important to make sure that stuff works,” said Green.
Can the internet be saved from cybercriminals?
“I don't know if it needs saving,” said Green. “I think of it like it’s just like a city, right? There's all kinds of good things that happen and there are also bad things that happen.”
Paul sees it this way.
“I believe that hackers will always find a way to exploit it but we can get very close to trying to save it by putting the right security controls in, making the internet as safe as possible.” | |
Q:
Remove domain extension
So let's say I have just-a.domain.com,just-a-domain.info,just.a-domain.net how can I remove the extension .com,.net.info ... and I need the resultes in two variables one with the domain name and another one with the extension.
I tried with str_replace but doesn't work, I guess only with regex....
A:
preg_match('/(.*?)((?:\.co)?.[a-z]{2,4})$/i', $domain, $matches);
$matches[1] will have the domain and $matches[2] will have the extension
<?php
$domains = array("google.com", "google.in", "google.co.in", "google.info", "analytics.google.com");
foreach($domains as $domain){
preg_match('/(.*?)((?:\.co)?.[a-z]{2,4})$/i', $domain, $matches);
print_r($matches);
}
?>
Will produce the output
Array
(
[0] => google.com
[1] => google
[2] => .com
)
Array
(
[0] => google.in
[1] => google
[2] => .in
)
Array
(
[0] => google.co.in
[1] => google
[2] => .co.in
)
Array
(
[0] => google.info
[1] => google
[2] => .info
)
Array
(
[0] => analytics.google.com
[1] => analytics.google
[2] => .com
)
A:
$subject = 'just-a.domain.com';
$result = preg_split('/(?=\.[^.]+$)/', $subject);
This produces the following array
$result[0] == 'just-a.domain';
$result[1] == '.com';
A:
If you want to remove the part of the domain that is administrated by domain name registrars, you will need to use a list of such suffixes like the Public Suffix List.
But since a walk through this list and testing the suffix on the domain name is not that efficient, rather use this list only to build an index like this:
$tlds = array(
// ac : http://en.wikipedia.org/wiki/.ac
'ac',
'com.ac',
'edu.ac',
'gov.ac',
'net.ac',
'mil.ac',
'org.ac',
// ad : http://en.wikipedia.org/wiki/.ad
'ad',
'nom.ad',
// …
);
$tldIndex = array_flip($tlds);
Searching for the best match would then go like this:
$levels = explode('.', $domain);
for ($length=1, $n=count($levels); $length<=$n; ++$length) {
$suffix = implode('.', array_slice($levels, -$length));
if (!isset($tldIndex[$suffix])) {
$length--;
break;
}
}
$suffix = implode('.', array_slice($levels, -$length));
$prefix = substr($domain, 0, -strlen($suffix) - 1);
Or build a tree that represents the hierarchy of the domain name levels as follows:
$tldTree = array(
// ac : http://en.wikipedia.org/wiki/.ac
'ac' => array(
'com' => true,
'edu' => true,
'gov' => true,
'net' => true,
'mil' => true,
'org' => true,
),
// ad : http://en.wikipedia.org/wiki/.ad
'ad' => array(
'nom' => true,
),
// …
);
Then you can use the following to find the match:
$levels = explode('.', $domain);
$r = &$tldTree;
$length = 0;
foreach (array_reverse($levels) as $level) {
if (isset($r[$level])) {
$r = &$r[$level];
$length++;
} else {
break;
}
}
$suffix = implode('.', array_slice($levels, - $length));
$prefix = substr($domain, 0, -strlen($suffix) - 1);
| |
Belief in misinformation causes confusion, reduces trust in authorities and encourages risky behaviours that can cause significant harm to health, as exemplified by the COVID-19 pandemic. Social media platforms have taken several policy measures to address this challenge; working with independent fact-checking companies to label inaccurate content, promoting verified information through prompts of fact-checked articles, or tailoring the algorithm to demote false posts in the newsfeed. But how effective are these measures? I aim to address this issue with a focus on Facebook and its policies to combat health-related misinformation in the context of India. My study has three key goals. First, I will evaluate the effectiveness of specific policies currently used by Facebook to debunk misinformation using an online experiment. Second, I aim to examine policy design tweaks informed by behavioural science to improve the effectiveness of these existing policies. Finally, I will examine how core aspects of users’ identities interact with the content of inaccurate posts to impact the efficacy of the policies, accounting for potential demand-side factors that contribute to the spread of misinformation.
For more information and to request a link to join online, visit the CESS events listings. | https://www.nuffield.ox.ac.uk/news-events/events-and-seminars/cess-colloquium-mt22-week-1/ |
English, The Universal Language
Over a hundred years ago, in the late 19th century, a Polish-Jewish eye doctor named Dr. Ludwig Lazarus Zamenhof wanted to bridge the gaps and misunderstandings between different ethnic groups that he grew up around. Being from a Polish city that, at the time, was a polyglot, multi-ethnic mixture of Poles, Russians, Jews, Lithuanians, and Germans, he saw there was a great deal of distrust between each group, and he believed it was due to the language barriers that each imposed. To create a common ground between every group, he created an international, universal language called Esperanto (Yaffe, 2017). While it was a great idea to create a language that did not belong to any ethnic group and could be used universally, it did not take off in the 20th century as Dr. L.L. Zamenhof had hoped it would. Fast forward to the late 20th and early 21st century, and you will find that there is a universal language— English.
This post was written by our TEFL certification graduate Gabrielle N.
Boost of popularity
Within the last couple of decades, English has become more and more important. It has taken on the role as the global language. It has become extremely important for travel. One reason to learn English as a second language is that it will enable you to communicate in different countries that you may not know the native language of. For example, let’s say that a young couple from China wants to travel to a few European countries over the spread of 4 months. They want to travel to Italy, France, Germany, and Poland, spending one month in each place. In each country, a different language is spoken. While it would be a good idea to learn a few basic phrases and greetings in each language, it would be very difficult to study four new languages in such a short period of time. What if they are in trouble or are lost and need directions? They cannot assume that most Europeans speak Chinese. However, they can make the assumption that most Europeans speak English. English is the universal language, and it is one of the most widely spoken second-languages in the world. While of course, you should always try to speak the native language of the country that you are visiting, if all else fails, give English a shot— someone is bound to speak it.
Also Read: 5 Advantages and Disadvantages of Teaching Business English
The language of freedom
In addition to the growing importance of English in the world of travel, it is also growing to be extremely important for the business. The world’s growing globalism and inter-connectivity demand quick and appropriate forms of communication. Companies from all over the world hold trade relations, and it is crucial that they share a common language to communicate. English is the go-to language for many internationally acting companies and agents. This is not only true for companies that do business within the English-speaking world, but also for companies from other countries that use English as their chosen language to communicate. Therefore, an understanding and knowledge of English that is specifically used within business contexts is very important. Being able to write and respond to emails, make phone calls, give presentations and reading company reports and memos all in English are just a few of the everyday tasks that are becoming a requirement for employees. Having a working knowledge of English specifically used for business purposes is essential for many jobs.
Also Read: 6 Essential Roles of an EFL Teacher
Are you ready to spread English across the globe?
Overall, it is safe to say that English can be found nearly everywhere in the world. It is a traveler’s back-up language when they are in a country where their mother tongue is not spoken. It is also the primary language used in the world of international business, and more and more employers are requiring that their employees are able to speak English. Unlike Esperanto, English has become the modern-day global language, and I can only predict that more people will be speaking it as their second language for travel and business purposes.
Apply now & get certified to teach english abroad!
Speak with an ITTT advisor today to put together your personal plan for teaching English abroad!
Send us an email or call us toll-free at 1-800-490-0531 to speak with an ITTT advisor today.
Related Articles: | https://www.teflcourse.net/blog/the-universal-language-ittt-tefl-blog/ |
Recipe: Good Kabocha Squash Croissants
Kabocha Squash Croissants.
Nowdays, you should can have Kabocha Squash Croissants using 12 ingredients and 16 steps. Here is how the way you achieve that.
Ingredients of Kabocha Squash Croissants
- It’s 150 grams of Bread (strong) flour.
- It’s 50 grams of Cake flour.
- You need 100 grams of Kabocha squash.
- Prepare 5 grams of Skim milk powder.
- Prepare 10 grams of Sugar.
- Prepare 3 grams of Natural Salt.
- You need 15 grams of Butter (unsalted).
- It’s 130 grams of Soy milk.
- It’s 3 grams of Dry yeast.
- Prepare 3 tbsp of Grated cheese.
- You need of Toppings (to taste):.
- You need 1 of Powdered cheese / cinnamon sugar / Sliced almonds.
Kabocha Squash Croissants instructions
- Cut the kabocha squash into small chunks and soften either by boiling or popping them in the microwave..
- Add all of the ingredients except for the toppings and grated cheese into the bread machine and let the machine do the work until the first rising..
- Once risen, take out of the bread machine, roll into a ball and leave to rest for 15 minutes..
- Roll the dough into a 18 x 30 cm rectangle and spread 1 tablespoon of grated cheese around the center..
- Fold into 3 layers and roll out to the original size..
- Turn the dough 90°, spread another tablespoon of grated cheese in the middle, fold into 3 layers again and roll out once more..
- Repeat steps 4 & 5 once more. Don't worry if the dough tears a little here, it's not filled with butter..
- Roll the dough out to 18 x 30 cm again and cut into 8 triangles as shown in the photo..
- Make a 1cm cut in the middle of the triangle and whilst stretching the tips of pastry a little, curl them away from you as shown in the photo..
- Now roll it into a croissant shape. Spray with water and wrap to prevent drying out. Leave to rise until double in size..
- .
- Brush over the glaze and top with what you like..
- Bake in an oven preheated to 200°C for 13 – 14 minutes..
- Roll up the left over croissant dough and bake these too!.
- .
- These croissants are unsweetened so they make great sandwiches as well.. | https://noiseworx.info/1360-recipe-good-kabocha-squash-croissants/ |
Alien Shaped Ball Point Pen - Chrome Colored Silver Body .
Refill Easily Replaceable - Writes In Black Ink.
Available In Silver Body As Shown- Length 6"
Case Pack=432 Pieces Case Weight=46 Lbs Case Size Approximately 26" x 19" x 16" | http://www.chulani.com/products/733.htm |
It’s a thought that most people come across at some point in their life; “What would I do if I could stop time?” This is commonly accepted to be impossible. Why, though, is it? It is more than a technological barrier that stops you from being able to do this; the very laws of nature are in play here.I want to address three things here: what a timeless world would be like, why the conventional idea is impossible, and how it could hypothetically be possible, but maybe not to your satisfaction.A TIMELESS WORLDLet’s assume for just a moment that you have achieved the impossible and have stopped time. Keep in mind this scenario is purely hypothetical. So, what is it like? Discussing this will partially address why it is not a possibility, but will not be its main focus. It will also help us figure out what it is that we want out of stopping time.
So, by your frame of reference, time is stopped. All the people around you have frozen solid. Wind stops blowing, water stops running, and the Earth stops turning.Sound waves through air.Image Credit: Wikimedia CommonsBefore you run off with glee to rob a bank or stick your friend’s finger up their nose, there are some things you should be aware of. This is all under the assumption that everything that makes up you, all the cells, microbes, and atoms, are the only things that are still affected by time. Everything else is at a stand-still.
To keep this thought experiment relatively easy, let us also assume that the laws of nature are still in effect. That is, we will contemplate how the laws would behave in a frozen world, the laws having not disappeared entirely because their effect is not in motion. This is a slight contradiction because we are breaking a few physical laws by stopping time. As you begin to take your first steps, you realize you are stuck in place. The atmosphere is also frozen so you are stuck in position, unable to maneuver around the molecules in the air. On this note, you would be unable to breath, as there is no way to intake the motionless air into your lungs. Perhaps you try to call out for help (forgetting you are the only conscious person around) and find that no sound can resonate through the environment, being incapable of using the atmosphere as a transmitter of sound waves.
Then you freeze to death, the world having ceased to emit any heat.So let’s say you and the atmosphere still move, or perhaps you have the ability to reinstate time/motion into things you interact with. So you can push the atmosphere out of the way, as you do when you walk in normal everyday life, or use it for oxygen. We will also give you heat, so that you can survive longer than a few moments. Come to think of it, we should put the entire electromagnetic spectrum back in motion – heat radiation is a part of the electromagnetic spectrum, in which our visible light also lies – otherwise you would be unable to see, as photons would not be moving into your eyes. If you had the ability to move, you could move into the light and capture it as you move along, but light is constantly moving around you from all directions, so you would capture light from every direction around you. It is unlikely your brain would be able to decipher this information.
So you get heat, light, sound, breath, and the convenience of moving. There is one other obstacle we will have to deal with, though this one isn’t as bad as freezing to death.An excerpt from Principia, Newtons book in which he describes gravity.
Image Credit: Wikimedia commonsA few seconds in, and you will realize that gravity no longer affects you. When Newton first described gravity in Principia, the force was believed to move instantaneously across space, having no speed limit. If this were true, then you would probably be able to have gravity in a timeless world. However, since Newton, the notion of infinitely fast gravity has been debunked.
It has to follow the universal speed limit (light speed) like everything else.THE IMPOSSIBILITYWhat we have talked about so far have been, for the most part, hindrances to your ability to function in a world without time, being the time bound beings that you are. But they do not necessarily describe why this concept is not possible.Recall that the speed of light – described mathematically as c – is approximately 300,000,000 meters per second. In two seconds, light travels 600,000,000 meters. In zero seconds, light travels zero meters. If time were stopped zero seconds would be passing, and thus the speed of light would be zero.
In order for you to stop time, you would have to be traveling infinitely fast. Nothing can travel faster than light (let alone infinitely fast) without gaining infinite mass and energy, according to Einstein’s theory of relativity.THE POSSIBILITYThere are ways you could theoretically “stop time”, but many of these have hindrances as well. The most convenient way to do it is to change your definition. We don’t really need to stop time completely, but perhaps enough so that you could observe the world moving at a very slow rate. Here’s how to do it. One way is to go to a universe where the laws of physics allow for this.
Another conceivable way is to freeze the universe, thus slowing molecular motion. You would not be able to completely stop the universe this way, because as of right now, zero degrees Kelvin (absolute zero) has not been reached, and it may not be possible. Another issue is that heat is an energy, and energy is only ever transferred. Because of this you would need to displace the heat into another place, but what other place would that be besides the universe, and how could you possibly do this? This applies even to removing most of the heat from objects and not all of it, so maybe we could find a way to technologically freeze a planet or a local area so that molecular motion is slower. Trouble is you would probably kill everybody; and imagine how enjoyable a nearly absolutely frozen wasteland would be.Let’s do the opposite, something that was done in the movie Clockstoppers.
In this movie, they speed up the atoms of a person so that time is moving extremely slow, but not frozen. Trouble with this is that molecular motion and heat are linked. If your molecules are moving vibrating quickly, you would also be very very hot… And it’s hard to predict how this would effect your perception of things.
An illustration of a black hole.Image Credit: Wikimedia commonsAnother way to “stop time” is to put whatever it is you wish to stop near a black hole. I won’t go too in depth with black holes as we already have plenty of articles on the subject, but say you threw something (a clock, perhaps) into a black hole, as it got closer and closer to the black hole it would appear to slow down. But from its perspective, you would speed up.Much is left to be understood about how time works and what it really is, but it is a great mind exercise to think about things like traveling through, perceiving, and stopping time.
It is a difficult subject to ponder on as time is not it’s own substance, as far as we understand it, but the succession of events within our own perception of the world. It deserves pondering, as it is the most fundamental force in the universe. It lets everything exist, and change, and I doubt imagining something outside of it is easy for time-bound beings like us.One final way to stop time: Take a picture. | https://wallaceandjames.com/its-not-be-its-main-focus-it-will/ |
---
abstract: 'Identifying strongly connected substructures in large networks provides insight into their coarse-grained organization. Several approaches based on the optimization of a quality function, e.g., the modularity, have been proposed. We present here a multistep extension of the greedy algorithm (MSG) that allows the merging of more than one pair of communities at each iteration step. The essential idea is to prevent the premature condensation into few large communities. Upon convergence of the MSG a simple refinement procedure called “vertex mover” (VM) is used for reassigning vertices to neighboring communities to improve the final modularity value. With an appropriate choice of the step width, the combined [MSG-VM ]{}algorithm is able to find solutions of higher modularity than those reported previously. The multistep extension does not alter the scaling of computational cost of the greedy algorithm.'
author:
- Philipp Schuetz and Amedeo Caflisch
title: |
Efficient modularity optimization by\
multistep greedy algorithm and vertex mover refinement
---
Introduction
============
The networks under study in natural and social sciences often show a natural divisibility into smaller modules (or communities) originating from an inherent, coarse-grained structure. In general, these modules are characterized by an abundance of edges connecting the vertices within individual communities in comparison to the number of edges linking the modules.
To detect these partitions several algorithm- or score-based approaches have been developed and applied. Very popular became the approach introduced by Girvan and Newman [@Newman2004] based on the quality function called “modularity” for partition assessment. This scoring function compares the actual fraction of intracommunity edges with its expectation in the random case given an identical degree distribution. The partition with the highest value of the scoring function is then considered to be the optimal splitting. The modularity $Q$ is defined (for undirected networks) as $$Q = \sum_{i=1}^{N_C} \left [ \frac{I(i)}{L} - \left ( \frac{d_i}{2 L} \right )^2 \right ]$$ with $I(i)$ the weights of all edges linking pairs of vertices in community $i$, $d_i$ the sum over all degrees of vertices in module $i$, $L$ the total weight of all edges, and $N_C$ the number of communities.
Intrinsically, the modularity based approach does not prescribe the usage of a particular optimization procedure. In practice, a strategy for optimization has to be chosen. The modularity optimization is a NP-hard problem [@Brandes2006]. Therefore, only an exhaustive search reveals the optimal solution for a generic network. This type of search is extremely demanding and only in a few cases feasible. Thus, many heuristic approaches such as extremal optimization [@Duch2005], simulated annealing [@Guimera2005], and the greedy algorithm [@Newman2004a] have been developed, refined, and successfully applied. Among the published approaches the greedy algorithm is one of the fastest techniques [@Danon2005]. On the other hand, many examples show that the greedy algorithm is not capable of finding the solutions with the highest modularity value. Furthermore, recent studies have provided evidence that modularity [@Fortunato2007] and Potts model based approaches [@Kumpula2007] are endowed with an intrinsic resolution limit (small modules are not detected and amalgamated into bigger ones). Thus, each community has to be refined by subduing it as a separate network to the community detection algorithm. Therefore, a fast and accurate optimization technique is necessary.
In this article, we enhance the greedy algorithm by a multistep feature in combination with a local refinement procedure. The enhanced algorithm finds partitions with higher modularity values than previously reported. This paper is organized as follows. In Sec. \[algorithm\] we introduce both procedures and describe the motivation for their construction. In addition, we discuss performance oriented implementations and estimate their running times. Benchmarking results for a set of real-world networks and a comparison with other published results are presented in Sec. \[benchmarks\]. The conclusions are in Sec. \[conclusions\]. In this paper, all networks are considered as undirected. The extension to directed networks is straightforward.
------------------------------------------------------------------------
Each vertex is a community Calculate the modularity change matrix $\Delta Q$ Determine the community degrees $d_i$ MergeCommunities(i,j)
------------------------------------------------------------------------
The Algorithm {#algorithm}
=============
Multistep Greedy algorithm (MSG)
--------------------------------
The classical greedy algorithm (first application in Ref. [@Newman2004a]) joins iteratively the pair of communities that improves modularity most in each step. The essential idea of the “multistep greedy” algorithm (MSG) is to promote the simultaneous merging of several pairs of communities at each iteration. The pseudocode of the MSG algorithm is presented in algorithms \[concept\] and \[details\], and an illustrative example is given in Fig. \[example\]. The MSG-algorithm starts with each vertex separated in its own community. At each iteration the modularity change $\Delta Q_{ij}$ upon merge of each pair of connected communities $(i,j)$ is calculated (while nonconnected pairs are ignored because their merging yields a negative modularity change). The triplets $(i,j,\Delta Q_{ij})$ are parsed in the order of decreasing $\Delta Q$-value and increasing community index. Those community pairs $(i,j)$ are joined which fulfill the following two criteria:
1. The modularity change $\Delta Q_{ij}$ is within the $l$ most favorable values (levels) and positive.
2. “Touched-community-exclusion-rule” (TCER): Neither module $i$ nor $j$ is present in another pair inducing a higher modularity change.
Convergence is reached when all pairwise merges of communities decrease modularity (by induction one can prove that all merges in further iterations would decrease modularity). A *level* encompasses all triplets $(i,j,\Delta Q_{ij})$ with equal $\Delta Q_{ij}$-value and the *level parameter* $l$ is kept constant. By construction the level parameter is always smaller than the number of edges in the network.
{width="14.5cm"}
The multiple levels promote the concurrent formation of multiple centers. Simultaneously growing community centers hinder the condensation into few large communities (few formed communities scrape all vertices as the establishment of a new community is too expensive in modularity) as observed in the classical greedy algorithm. The TCER is a second mean against excessive aggregation into few large modules. This rule permits the addition of only one community to an existing community per algorithm iteration. Furthermore, the TCER guarantees that the modularity change upon all performed merges is just the sum over the corresponding $\Delta Q$ elements which improves efficiency.
Implementation details of MSG {#implementation-MSG}
-----------------------------
The key observation for an efficient implementation of the MSG is the following: Upon merge of communities $i$ and $j$ only those $\Delta Q$-elements concerning either of the two modules have to be recalculated. When the modules $i$ and $j$ are joined into a new one called $I$, the updated modularity changes $\Delta Q_{Ik}^{\rm new}$ (module $k$ is connected either to community $i$ or $j$) reads (see Sec. II in Ref. [@Clauset2004] for details) $$\label{merge-equation}
\Delta Q_{Ik}^{\rm new} = \left \{
\begin{array}{cl}
\Delta Q_{ik} + \Delta Q_{jk} & i,j \mathrm{ \; and \;} k\mathrm{\;pairwise \;connected} \\
\Delta Q_{ik} - \frac{d_j d_k}{2 L^2} & i \mathrm{\; and \; } k \; \mathrm{connected,}\; j \mathrm{\; and \; } k \; \mathrm{not} \\
\Delta Q_{jk} - \frac{d_i d_k}{2 L^2} & j \mathrm{\; and \; } k \; \mathrm{connected,}\; i \mathrm{\; and \; } k \; \mathrm{not} \\
\end{array} \right .$$ with $d_x$ the sum over all degrees of vertices in community $x=i,j$ and $L$ the total edge weight.
Further efficiency improvements are gained from an appropriate choice of data structures. A *set* (implementation taken from the <span style="font-variant:small-caps;">C++-STL</span>-library) is a sorted binary search tree. In a set individual elements can be found or inserted in $O(\log(n))$ time ($n$ the number of elements) and the extremal entries are found in constant time. The modularity changes are stored in the *$\Delta Q$* matrix implemented as vector of row structures. The $i$th row consists of a set with elements $(j, \Delta Q_{ij})$ ($j$ a module linked to the community $i$) ordered according to the community index $j$. This data structure obsoletes a separate storage of the topology information. The extraction of the best $l$ modularity changes is handled via the *level set*. For each pair of connected communities $i$ and $j$ the element $(\min\{i,j\},\max\{i,j\},\Delta Q_{ij})$ is added to the *level set*. The *level-set* elements are sorted with respect to decreasing $\Delta Q$ and increasing index values. The degree information is stored in a vector henceforth named *d*. In each iteration a Boolean vector called *touched* stores whether a community has already been modified in the same round. To save the time to determine the highest index of a present communities, the number of vertices (initial length) is chosen as length of the *touched* vector.
------------------------------------------------------------------------
Each vertex is a community Calculate community degrees $d$ and the $\Delta Q$ matrix Determine the initial modularity $Q\gets Q_0= - \sum_{i=1}^n \frac{d_i^2}{4 L^2} $ *level set* $\gets $ set of $\Delta Q$ elements $(i,j,\Delta Q_{ij})$, sorted with respect to decreasing $\Delta Q$ and increasing $ (i,j)$
$touched\gets (0,\ldots,0)$ Boolean, $N$-dimensional vector ($N = $ No. vertices) $MP\gets$ subset of *level-set* elements $(i,j,\Delta Q_{ij})$ with $\Delta Q_{ij} >0$ and $\Delta Q_{ij}$ among highest $l$ values
$\Delta Q_{ik} \gets \left \{
\begin{array}{cl}
\Delta Q_{ik} + \Delta Q_{jk} & i, k \; \mathrm{and}\; j,k \; \mathrm{are \; linked}\\
\Delta Q_{ik} - \frac{d_j d_k}{2 L^2} & i \mathrm{\; and \;} k \mathrm{\; are \; linked} \\
\Delta Q_{jk} - \frac{d_i d_k}{2 L^2} & j \mathrm{\; and \; } k \mathrm{\; are \; linked}
\end{array} \right . $ $\Delta Q_{ki}\gets \Delta Q_{ik}$ Update the *level set* Update the modularity $Q\gets Q + \Delta Q_{ik}$ Empty $\Delta Q_{j.}$ Flag $touched_i, touched_j\gets 1$ Update degrees: $d_i\gets d_i+d_j, d_j \gets 0 $
------------------------------------------------------------------------
The implementation details of the MSG algorithm are listed in algorithm \[details\]. The calculation of the community degrees involves one parse of the edge information. In the second parse of the edge information the $\Delta Q$ matrix and the *level set* is filled. The initial modularity change $\Delta Q_{ij}$ upon join of modules (at this stage the vertices) $i$ and $j$ is calculated as (see Sec. II in Ref. [@Clauset2004] for details) $$\Delta Q_{ij} = \frac{I}{L} - \frac{d_i d_j}{2 L^2}$$ with $I$ the weight of the edges connecting the vertices $i$ and $j$, $d_{x}$ the degree of vertex $x=i,j$, and $L$ the total edge weight. The modularity value of the initial partition is ($N$ the number of vertices) $$Q_0 = - \sum_{i=1}^N \frac{d_i^2}{4 L^2}.$$ The algorithm iteration starts by initializing the *touched* vector. Subsequently, the *Level*-set is parsed and all elements with positive $\Delta Q$ value, whose modularity change is among the best $l$ (external *level parameter*) different values, are stored in a set named *MP* conserving the order of the *level set*. In this order the module pairs are merged unless one of them was part of a amalgamation in the same algorithm iteration. In the merge process, the changed $\Delta Q$ matrix elements are calculated as described at the beginning of this paragraph. To determine which case applies in Eq. (\[merge-equation\]) the fact that each row of the $\Delta Q$ matrix is ordered with respect to the community index can be used. More precisely, parse for the merge of modules $i$ and $j$ the corresponding rows concurrently. For each row define an momentarily considered element $p$. If the community index of $p_i$ is equal to the one of $p_j$, the first case applies and advance both $p$’s to the next element in the corresponding row. If the index $k$ of $p_i$ is lower than the one of $p_j$ calculate the $\Delta Q_{Ik}^{\rm new}$ element ($I$ the name of the merged community) according to the second case and advance (if possible) only $p_i$. If the module index of $p_i$ is larger than the one of $p_j$, proceed analogously. If one $p$ reaches the end of the row, merge the remaining elements of the other row according to the respective rule. This procedure will be called “asynchronous parsing” in Sec. \[complexity-MSG\]. It is customary to update each $\Delta Q$ element after calculation. To complete the merge process it remains to update the community degrees and to flag the modified communities in the *touched* vector.
Running time estimation of MSG {#complexity-MSG}
------------------------------
As we adopted the modularity change calculation of Clauset et al. (Sec. II in Ref. [@Clauset2004]) we can adopt their method of running time estimation as well. First, we observe that the update of one element in the $\Delta Q$ matrix and the *level set* costs in the worst case $O(\log(N))$ (insertion in set, each community has at most $N$ neighbors with $N$ the number of vertices) and $O(\log(M))=O(\log(N))$ running time (the number of distinct edges $M$ is bounded by the square of the number of vertices $N^2$), respectively.
Merging communities $i$ and $j$ involves an update of the $\Delta Q$ matrix and the *level set* for each element of the corresponding rows of the $\Delta Q$ matrix . The calculation of each changed value can be achieved in constant time as during the asynchronous parsing it is known whether the other community is linked as well and all other information (community degrees) is stored in a vector. Thus, the total running time contribution of one merging event is $O((d_i + d_j) \log(N))$ with $d_k$ the number of edge starts/ends on vertices of community $k = i,j$. In the worst case all communities are changed in one algorithm round. As the sum over all $d_i$ values is twice the number of distinct edges, the contribution of the merging processes in one algorithm round is at most $O(M \log(N))$. The other steps of one algorithm round are less consumptive: The extraction of pairs belonging to the best $l$ levels can be performed in constant time. The same is true for the update of the degree information. If $D$ is defined as the depth of the dendrogram of communities, at most $D$ algorithm rounds have to be performed. Thus, the running time expectation for the iterative part is $O(D M \log(N))$ which is identical to the complexity of the classical greedy algorithm [@Clauset2004].
The initialization involves the read-in processes of the edge information ($M$ constant time operations), the degree calculation (part of read-in process), the calculation of the initial modularity (constant time operation on $N$ elements) and finally the generation of the $\Delta Q$ matrix and the *level set* at costs $O(M \log(N))$ ($M$ insertions in a set with at most $N$ or $M$ elements, respectively). In the worst case the expected contribution of the initialization to the running time is $O(M \log(N))$.
In the precedent paragraphs we have shown that the MSG greedy algorithm has the total complexity $O(D M \log(N))$. Among the published strategies for modularity optimization the classical greedy algorithm [@Clauset2004] is the fastest [@Danon2005]. As the MSG shares the worst case expectation for the running time with the classical greedy algorithm, we conclude that the MSG is one of the fastest procedures for modularity optimization.
Vertex mover (VM)
-----------------
To further improve modularity by “adjusting” misplaced vertices, a refinement step called “vertex mover” (VM) is applied upon convergence of the MSG algorithm. In principle, it could also be applied to other modularity optimization procedures. In the VM, the list of vertices is parsed in the order of increasing degree and vertex index (to resolve the degeneracy of multiple vertices with equal degree) and every vertex is reassigned to the neighboring community with maximal modularity improvement. This parsing-and-reassignment procedure is repeated until no modularity improvement is observed.
The VM procedure is similar to the Kernighan-Lin algorithm [@KernighanLin72] (applied to modularity optimization in Ref. [@Newman2006a]). In contrast to the Kernighan-Lin algorithm the VM procedure has a perfectly local focus. In other words, instead of repetitively searching for the optimal vertex to reassign, the VM procedure parses the vertices in the aforementioned order and identifies the optimal community for the considered vertex. Furthermore, each reassignment of the VM approach improves modularity. Therefore, the selection of the optimal intermediate partition as in the Kernighan-Lin algorithm is not necessary.
---------------------------------------------------------
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VM implementation {#performance-VM}
-----------------
The modularity change $\Delta Q$ upon reassignment of vertex $v$ from community $i$ to $j$ can be written as $$\label{formula}
\Delta Q = \frac{\mathrm{links}(v \leftrightarrow j) - \mathrm{links}(v \leftrightarrow i)}{L} - \frac{k_v \left ( d_j - d_{i \setminus v}\right ) }{2 L^2}$$ with $k_v$ the degree of vertex $v$, $d_j$ the sum over the degrees of all vertices in community $j$, $d_{i \setminus v} = d_i - k_v$ the corresponding degree for community $i$ without vertex $v$, and $L$ the total weight of all edges.
The most time consuming part of the VM is the calculation of the modularity changes upon reassignment of the vertices. Consequently, Eq. (\[formula\]) reduces this bottleneck to the calculation of weight of the edges connecting the vertex to the neighboring communities. [ The connectivity information of vertex $v$ is stored in a sparse vector \[i.e., a vector of elements $(u,w_{vu})$ with $u$ a vertex linked to $v$ and $w_{vu}$ the total weight of all edges connecting vertices $u$ and $v$\]. These rows are stored in a vector and form the topology matrix. To determine the total edge weight connecting vertex $v$ with community $j$ the $v$th row is parsed and for each entry the weight is added to the subtotal edge weight of the corresponding community. To keep access times short a $N$-dimensional vector ($N$ the number of vertices) is chosen to store the intermediate $\mathrm{links}(v \leftrightarrow j)$ results. The optimal reassignment partner for vertex $v$ is the community with smallest index yielding the maximal modularity improvement. ]{}
Estimation of VM running time {#complexity-VM}
-----------------------------
Calculating the modularity changes upon reassignment of one vertex to any neighboring community involves one parse of its edge list supplemented with direct memory access to determine the community affiliation and some constant time operations for the actual modularity calculation. Therefore, the running time contribution of one vertex is proportional to its degree. One algorithm round requires $O(L) = O(\sum_i d_i)$ running time. The estimation of the number of needed iterations is not possible as it depends on the quality of the MSG result. In all examples tested by us the running time of the VM was always at least one order of magnitude smaller and less than one minute even for the biggest networks under study.
------------------------ ------------------------------- ---------- --------- -- --------------- ------- ------------ ------- -- ------- ------------ -------
Name Ref. Vertices Edges $l_{\rm opt}$ Time $[s]$ $N_C$ Time $[s]$ $N_C$
Zachary Karate Club [@Zachary1977] 34 78 3 0.398 na 4 0.381 na 3
Metabolic *E. coli* [@Ma2003] 443 586 6, 8 0.816 na 19 0.811 na 20
College Football [@Girvan2002] 115 613 1 0.603 na 8 0.556 na 6
Metabolic *C. elegans* [@Jeong2000] 453 1899 209 0.450 na 8 0.412 na 13
Jazz [@Gleiser2003] 198 2742 566 0.445 na 4 0.439 na 4
Email [@Guimera2003] 1133 5451 56 0.575 na 10 0.503 na 12
Yeast (PPI, CP) [@Krogan2006] 2552 7031 35 0.706 na 33 0.675 na 51
M. Karplus [@karplus] 1167 13423 91 0.316 na 11 0.264 na 18
PPI-CP *S. cerevisiae* [@Colizza2005] 4626 14801 170 0.545 na 24 0.500 na 38
PPI *S. cerevisiae* [@Colizza2005] 4713 14846 170 0.546 na 65 0.501 na 81
M. Karplus weighted [@karplus] 1167 18991 173 0.320 na 13 0.296 na 11
Internet [@AS2001] 11174 23409 278 0.625 8 35 0.584 8 49
PGP-key signing [@Guardiola2002; @Boguna2004] 10680 24340 44 0.878 2 140 0.849 3 195
Word Association (CP) [@Nelson2004] 7204 31783 71 0.541 4 16 0.452 7 52
Word Association [@Nelson2004] 7207 31784 97 0.540 3 17 0.465 7 38
Collaboration [@Newman2001b] 27519 116181 153 0.748 14 82 0.661 103 381
WWW [@Albert1999] 325729 1117563 3034 0.939 562 674 0.927 7640 2183
Actor [@Barabasi1999] 82583 3666738 2429 0.543 1722 238 0.470 6288 406
Actor weighted [@Barabasi1999] 82583 4475520 389 0.536 5099 322 0.480 3541 361
------------------------ ------------------------------- ---------- --------- -- --------------- ------- ------------ ------- -- ------- ------------ -------
Network $Q_{\rm max}^{\mbox{\tiny MSG-VM}}$ $Q_{\rm pub}$ Source Method
------------------------ ------------------------------------- --------------- ---------------- ----------------
Zachary Karate Club 0.398 0.419 [@Newman2006a] [@Newman2006a]
College Football 0.603 0.601 [@Girvan2002] [@Girvan2002]
Metabolic *C. elegans* 0.450 0.435 [@Newman2006a] [@Newman2006a]
Jazz 0.445 0.445 [@Newman2006a] [@Duch2005]
Email 0.575 0.574 [@Newman2006a] [@Duch2005]
PGP-key signing 0.878 0.855 [@Newman2006a] [@Newman2006a]
Collaboration 0.748 0.723 [@Newman2006a] [@Newman2006a]
: \[performance-comparision\]Comparison of maximal value of modularity obtained by the [MSG-VM ]{}algorithm $Q_{\rm max}^\mathrm{{MSG-VM }}$ with previously published results $Q_{\rm pub}$. The highest published value was extracted from the referenced paper (“Source”) where it has been calculated by the “Method” whose reference is listed in the last column.
Results {#benchmarks}
=======
Test set of networks {#benchmarking-sets}
--------------------
For benchmarking algorithms that optimize modularity the networks commonly used are the collaboration network (coauthorships in cond-mat articles) [@Newman2001b], the graph of metabolic reactions in *Caenorhabitis elegans* [@Jeong2000], the email network [@Guimera2003], the network of mutual trust (PGP-key signing) [@Guardiola2002; @Boguna2004], the conference graph of college football teams [@Girvan2002], the network of jazz groups with common musicians [@Gleiser2003] and the Zachary karate club example [@Zachary1977]. In addition, we include less frequently used examples such as the graph of the metabolic reactions in *Escherichia coli* [@Ma2003], two different data set describing the protein-protein interactions in S. cerevisiae (budding yeast) [@Krogan2006; @Colizza2005] with labels “PPI” and “yeast.” To cover linguistic applications we benchmark the word association network [@Nelson2004] and the graph of the co-appearing words in publication titles (co)authored by Martin Karplus [@karplus] who has the third highest $h$-factor [@Hirsch2005] among chemists [@Ball2007]. Further aspects of social webs were incorporated by considering the graph of costarring actors in the IMDB database [@Barabasi1999]. Noticeable, the actor network - being the network with the largest number of edges - serves as a proof of concept for such big networks being treatable as well. From computer science we include the internet routing network [@AS2001] and the graph of World Wide Web pages [@Albert1999]. With this selection of networks most currently known application fields of networks are covered. To study the effect of disconnected graphs and weighted networks, we consider in both cases the full network as well as the largest connected component (suffix “CP”) and the unweighted variant, respectively. Unless stated otherwise the networks are treated unweighted.
Dependence on $l$ and vertex labeling
--------------------------------------
It is important to investigate the robustness upon the choice of $l$ and to determine the highest modularity values achievable with the [MSG-VM ]{}algorithm. There is a minor dependence on the value of $l$ (Fig. \[profiles\]) which changes the [MSG-VM ]{}modularity by less than 2 % for large networks. Moreover, the maximal modularity is obtained with $l < 300 $ for 14 of the 19 networks (Table \[real-world\]). An empirical formula for the optimal choice of the level parameter will be presented elsewhere.
Noteworthily, for a labeled graph and a chosen level parameter the algorithm is deterministic. To assess the contribution of the labeling, the benchmarking procedure is performed also on hundred copies of the smallest ten networks with permuted vertex labels. This permutation leaves the topology invariant, but modifies the order in which the community pairs are considered. In comparison to the maximal modularity value found for the unscrambled variants a maximal improvement of 0.94 % is observed.
Performance and running time {#performance-results}
----------------------------
The modularity values obtained with the [MSG-VM ]{}approach are listed in Table \[performance-comparision\]. For five of the seven networks considered here the [MSG-VM ]{}algorithm finds solutions with modularity higher than previously published. Only for the Zachary Karate network the [MSG-VM ]{}procedure yields a smaller modularity value. For the jazz network a solution with the identical $Q$ value is obtained. For the networks without published modularity values we compare the optimal values obtained by the [MSG-VM ]{}algorithm with the classical greedy algorithm for modularity optimization as introduced by Newman [@Newman2004a] in Table \[real-world\]. We observe that the [MSG-VM ]{}algorithm outperforms the original greedy algorithm significantly.
The running time estimations in Secs. \[complexity-MSG\] and \[complexity-VM\] are based on a worst case scenario. To investigate the running time behavior on real-world examples, we compare the running times of the classical greedy variant and the [MSG-VM ]{}algorithm in Table \[real-world\]. These data show that given the appropriate level parameter choice the [MSG-VM ]{}algorithm is in almost all cases faster than the classical greedy algorithm and, at the same time, reaches a higher value of modularity.
Conclusions
===========
To prevent premature condensation into few large communities the greedy algorithm for modularity optimization has been extended by a procedure for simultaneous merging of more than one pair of communities at each step. Furthermore, this “multistep” greedy variant has been combined with a simple vertex-by-vertex a posteriori refinement. On seven networks with previously published modularity values the [MSG-VM ]{}algorithm combination outperforms all other frequently used, generic techniques except for the smallest of the seven examples. In addition, a single run of the [MSG-VM ]{}algorithm requires similar computer time as the greedy algorithm. In most cases less than 10 independent (i.e., embarrassingly parallel) runs of [MSG-VM ]{}are required to obtain a modularity within 1 % of the highest value because an empirical formula has been derived for the appropriate choice of the optimal step-width. Therefore, the [MSG-VM ]{}algorithm is an efficient tool to find network partitions with high modularity [^1].
Acknowledgments
===============
The authors thank Stefanie Muff and Francesco Rao for helpful discussions. Christian Bolliger, Thorsten Steenbock, and Dr. Alexander Godknecht are acknowledged for maintaining the Matterhorn cluster where most of the parameter studies were performed. We are thankful to Drs. Arenas, Barabási, Gleiser, and Newman for providing the network data. This work was supported by a Swiss National Science Foundation grant to A.C.
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[^1]: The code is available at *http://www.biochem-caflisch.uzh.ch/communitydetection/*
| |
---
abstract: 'A linear dispersive mechanism leading to a burst in the $L_\infty$ norm of the error in numerical simulation of polychromatic solutions is identified. This local error pile-up corresponds to the existence of spurious caustics, which are allowed by the dispersive nature of the numerical error. From the mathematical point of view, spurious caustics are related to extrema of the numerical group velocity and are physically associated to interactions between rays defined by the characteristic lines of the discrete system. This paper extends our previous work about classical schemes to dispersion-relation preserving schemes.'
author:
- |
Claire David , Pierre Sagaut\
\
Université Pierre et Marie Curie-Paris 6\
Institut Jean Le Rond d’Alembert, UMR CNRS 7190\
Boîte courrier $n^0162$, 4 place Jussieu, F-75252 Paris cedex 05, France\
title: 'Spurious caustics of *Dispersion Relation Preserving* schemes'
---
*[Keywords]{}*: Dispersion; numerical schemes; spurious caustics.
Introduction {#sec:intro}
============
The analysis and the control of numerical error in discretized propagation-type equations is of major importance for both theoretical analysis and practical applications. A huge amount of works has been devoted to the analysis of the numerical errors, its dynamics and its influence on the computed solution (the reader is referred to classical books, among which [@Hirsch; @vich; @lomax; @tapan-book]). The emergence of *Dispersion-Relation-Preserving (DRP)* schemes [@Tam]), which have the same dispersion relation as the original partial difference equations, enables one to have very accurate high order finite difference schemes.\
The two sources of numerical error are the dispersive and dissipative properties of the numerical scheme, which are very often investigated in unbounded or periodic domains thanks to a spectral analysis.\
It appears that existing works are mostly devoted to linear, one-dimensional numerical models, such as the linear advection equation
$$\label{transp}
\frac{\partial u}{\partial t}+c \, \frac{\partial u}{\partial x}=0$$
where $c$ is a constant uniform advection velocity.
The two sources of numerical error are the dispersive and dissipative properties of the numerical scheme, which are very often investigated in unbounded or periodic domains thanks to a spectral analysis. Following this approach, a monochromatic wave is used to measure the accuracy of the scheme. Such a tool is very powerful and provides the user with a deep insight into the discretization errors. But some results coming from practical numerical experiments still remain unexplained, despite the linear character of the discrete numerical model. As an example, let us note the sudden growth of the numerical error for long range propagation reported by Zingg [@zingg] for a large set of numerical schemes, including optimized numerical schemes.
The usual modal analysis is almost always applied to monochromatic reference solutions, with the purpose of analyzing the error committed on both their amplitude and their phase, leading to classical plots of the relative error as the function of the Courant number and/or the number of grid points per wavelength. Therefore, dispersive phenomena associated to polychromatic solutions are usually not taken into account.\
The present paper deals with the analysis of linear dispersive mechanism which results in local error focusing, i.e. to a sudden local error burst in the $L_\infty$ norm for polychromatic solutions. This phenomena is reminiscent of the physical one referred to as the caustic phenomenon in linear dispersive physical models [@witham], and will be referred to as the spurious caustic phenomenon hereafter. It extends our previous work [@Cl.; @David] to *DRP* schemes. The present analysis is restricted to interior stencil, and the influence of boundary conditions will not be considered.
The paper is organized as follows. Main elements of caustic theory of interest for the present analysis are recalled in section \[Caustiques\]. *DRP* schemes are presented in section \[DRPStudy\]. Their caustical analysis is exposed in section \[CaustiquesDRP\]. A numerical example is presented in section \[Example\].
Caustics {#Caustiques}
========
The solution of Eq. (\[transp\]) is taken under the form:
$$\label{depl} u(x,t,k)=e^{i\,(k\,x-\omega \, t)}$$
where $\omega = {\xi}_\omega+i \,{\eta}_\omega $ is the complex phase, and $k$ the real wave number. For dispersive waves, it is recalled that the group velocity $V_g (k)$ is defined as
$$\label{Vg} V_g (k) \equiv \frac{{\partial } \xi _\omega }{\partial
{k}}$$
A caustic is defined as a focusing of different rays in a single location. The equivalent condition is that the group velocity exhibits an extremum, i.e. there exists at least one wave number $k_c$ such that
$$\label{eq:caustic} \frac{{\partial } V_g}{\partial {k}} (k_c) =0$$
The corresponding physical interpretation is that wave packets with characteristic wave numbers close to $k_c$ will pile-up after a finite time and will remain superimposed for a long time, resulting in the existence a region of high energy followed by a region with very low fluctuation level.
The linear continuous model Eq. (\[transp\]) is not dispersive if the convection velocity $c$ is uniform, and therefore the exact solution does not exhibits caustics since the group velocity does not depend on $k$. The discrete solution associated with a given numerical scheme will admit spurious caustics, and therefore spurious local energy pile-up and local sudden growth of the error, if the discrete dispersion relation is such that the condition (\[eq:caustic\]) is satisfied. For a uniform scale-dependent convection velocity, such spurious caustics can exist in polychromatic solutions only, since they are associated to the superposition of wave packets with different characteristic wave numbers.\
Set:
$$k=\frac{\varphi \,\sigma}{c\,dt}$$
The general dispersion relation associated with the discrete scheme enables us to obtain the corresponding group velocity, given by:
$$\label{eq:Vg} V_g =h \frac{{\partial} \xi _\omega }{\partial
{\varphi}}$$
The numerical solution will therefore admits spurious caustics if
$$\frac{{\partial } V_g }{\partial {k}} = \frac{{\partial } V_g
}{\partial {\varphi}} \, \frac{{\partial } \varphi }{\partial {k}}=0
\Longleftrightarrow
\frac{{\partial } V_g }{\partial {\varphi}}=0$$
The corresponding values of $\varphi$ and $k$ will be respectively denoted ${\varphi}_c$ and $k_c$.
Spurious caustics are associated with characteristic lines given by
$$\frac{x}{t}=U_c$$
where
$$U_c=V_g(\varphi_c)$$
*DRP* schemes {#DRPStudy}
=============
The Burgers equation:
$$\label{Burgers} u_t + c\, u\, u_x - \mu \,u_{xx} = 0,$$
$c$, $\mu$ being real constants, plays a crucial role in the history of wave equations. It was named after its use by Burgers [@burger1] for studying turbulence in 1939.\
$i$, $n$ denoting natural integers, a linear finite difference scheme for this equation can be written under the form: $$\label{scheme} \displaystyle \sum \alpha_{lm}\,u_{l}^{m}=0$$
where: $${u_l}^m=u\,(l\,h, m\,\tau)$$ $l\, \in \, \{i-1,\, i, \, i+1\}$, $m \, \in \,
\{n-1,\, n, \, n+1\}$, $j=0, \, ..., \, n_x$, $n=0, \, ..., \,
n_t$. The $ \alpha_{lm}$ are real coefficients, which depend on the mesh size $h$, and the time step $\tau$.\
The Courant-Friedrichs-Lewy number ($cfl$) is defined as $\sigma = c \,\tau / h$ .\
A numerical scheme is specified by selecting appropriate values of the coefficients $ \alpha_{lm}$. Then, depending on them, one can obtain optimum schemes, for which the error will be minimal.\
$m$ being a strictly positive integer, the first derivative $\frac{\partial
u}{\partial x}$ is approximated at the $l^{th}$ node of the spatial mesh by:
$$\label{approx}
(\, \frac{\partial u}{\partial
x}\,)_l \simeq
\displaystyle \sum_{k=-m}^m \gamma_{k}\,u_{i+k}^n$$
Following the method exposed by C. Tam and J. Webb in [@Tam], the coefficients $\\gamma_{k}$ are determined requiring the Fourier Transform of the finite difference scheme (\[approx\]) to be a close approximation of the partial derivative $ (\, \frac{\partial u}{\partial x}\,
)_l$.\
(\[approx\]) is a special case of:
$$\label{approx_Cont}
(\, \frac{\partial u}{\partial
x}\,)_l \simeq \displaystyle \sum_{k=-m}^m \gamma_{k}\,u(x+k\,h)$$
where $x$ is a continuous variable, and can be recovered setting $x=l\,h$.\
Denote by $\omega$ the phase. Applying the Fourier transform, referred to by $\,\widehat{\, }$ , to both sides of (\[approx\_Cont\]), yields:
$$\label{Wavenb}
j\, \omega \, \widehat{u} \simeq \displaystyle \sum_{k=-m}^m \gamma_{k}\,e^{\,j\,k\,\omega\,h}\, \widehat{u}$$
$j$ denoting the complex square root of $-1$.\
Comparing the two sides of (\[Wavenb\]) enables us to identify the wavenumber $ \overline{\lambda}$ of the finite difference scheme (\[approx\]) and the quantity $\frac{1}{j}\,{\displaystyle \sum_{k=-m}^m
\gamma_{k}\,e^{\,j\,k\,\omega\,h}}$, the wavenumber of the finite difference scheme (\[approx\]) is thus:
$$\overline{\lambda}=-\,j\, \displaystyle \sum_{k=-m}^m \gamma_{k}\,e^{\,j\,k\,\omega\,h}$$
To ensure that the Fourier transform of the finite difference scheme is a good approximation of the partial derivative $ (\, \frac{\partial u}{\partial x}\, )_l$ over the range of waves with wavelength longer than $4\,h$, the a priori unknowns coefficients $\gamma_{k}$ must be choosen so as to minimize the integrated error:
$$\begin{array}{rcl}
{\mathcal E} &=&\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} | \lambda \,h- \overline{\lambda}
\,h|^2\,d(\lambda \,h)\\
&=&\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} | \lambda \,h+j\, \displaystyle \sum_{k=-m}^m \gamma_{k}\,e^{\,j\,k\,\omega\,h} \,h|^2\,d(\lambda \,h)\\
&=& \int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} | \zeta+j\, \displaystyle \sum_{k=-m}^m \gamma_{k}\,\left \lbrace \cos (\,k\,\zeta)+j\,\sin(\,k\,\zeta) \right \rbrace \,
|^2\,d \zeta \\
&=& \int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} \left \lbrace \left [ \zeta- \displaystyle \sum_{k=-m}^m \gamma_{k} \,\sin(\,k\,\zeta) \right ]^2+
\left [ \displaystyle \sum_{k=-m}^m \gamma_{k}\, \cos (\,k\,\zeta) \right ]^2\, \right \rbrace \,d
\zeta \\
&=& 2 \, \int_0^{\frac{\pi}{2}} \left \lbrace \left [ \zeta- \displaystyle \sum_{k=-m}^m \gamma_{k} \,\sin(\,k\,\zeta) \right ]^2+
\left [ \displaystyle \sum_{k=-m}^m \gamma_{k}\, \cos (\,k\,\zeta) \right ]^2\, \right \rbrace \,d
\zeta \\
\end{array}$$
The conditions that ${\mathcal E}$ is a minimum are:
$$\frac {\partial{\mathcal E}}{\partial \gamma_i} =0 \,\,\, , \,\,\,
i=-m, \ldots , \, m$$
i\. e.:
$$\label{RelDer}
\int_0^{\frac{\pi}{2}} \left \lbrace
\,-\,\zeta\,\sin(\,i\,\zeta)\, + \displaystyle \sum_{k=-m}^m \gamma_{k}
\,\cos\left(\,(k-i)\,\zeta \right) \right \rbrace \,d
\zeta =0$$
Changing $i$ into $-i$, and $k$ into $-k$ in the summation yields:
i\. e.:
Thus:
$$\label{Int1}
\int_0^{\frac{\pi}{2}} \displaystyle \sum_{k=-m}^m \left \lbrace
\gamma_{-k} + \gamma_{k} \right \rbrace
\,\cos\left(\,(k-i)\,\zeta \right) \,d
\zeta =0$$
which yields:
$$\frac{\pi}{2} \,\left \lbrace
\gamma_{-i} + \gamma_{i} \right \rbrace +\displaystyle \sum_{k \neq i,\, k=-m}^m
\left \lbrace \frac {
\gamma_{-k} + \gamma_{k} }{k-i} \right \rbrace
\,\sin\left(\,(k-i)\,\frac{\pi}{2} \right) \ =0$$
which can be considered as a linear system of $2\,m+1$ equations, the unknowns of which are the $ \gamma_{-i} +
\gamma_{i} $, $i=-m,\,\ldots, \,m$. The determinant of this system is not equal to zero, while it is the case of its second member: the Cramer formulae give then, for $i=-m,\,\ldots, \,m$:
$$\gamma_{-i} + \gamma_{i} =0$$
or:
$$\label{RelCoeffDRP1}
\gamma_{-i} =- \gamma_{i}$$
For $i = 0$, one of course obtains:
$$\gamma_0=0$$
All this ensures:
$$\label{RelCoeffDRP} \displaystyle \sum _{k=-m}^m \gamma_{k} =0$$
The values of the $\gamma_k$ coefficients are obtained by substituting relations (\[RelCoeffDRP1\]) into (\[RelDer\]):
$$\label{RelCoeffDRP} \displaystyle \sum _{k=-m}^m \gamma_{k} =0$$
$m$ being a strictly positive integer, a ${2m+1}$-points *DRP* scheme ([@Tam]) is thus given by:
$$\label{DRP}
\begin{aligned}
&-u_{i}^{n+1}+u_{i}^{n } +\frac{ \tau }{h}\, \displaystyle \sum
_{k=-m}^m \gamma_{k}\,u_{i+k}^{n } =0
\end{aligned}$$
where the $\gamma_{k}$, $k\in \{-m,m\}$ are the coefficients of the considered scheme, and satisfy the relations (\[RelCoeffDRP1\]).
General study of *DRP* schemes {#CaustiquesDRP}
==============================
The dispersion relation related to a general *DRP*-scheme (\[DRP\]) is given by:
$$\begin{aligned}
&\frac{ \tau }{h}\, \displaystyle \sum _{k=-m}^m \gamma_{k}\,e^{i
\,\left(k\, \varphi +\xi _{\omega }\,\tau \right)-B \,\tau +e^{i
\,\xi _{\omega }\,\tau-B \,\tau}}-1=0
\end{aligned}$$
from which it comes that
$$\begin{aligned}
& i\,{ \xi _{\omega }\,\tau }=B \,\tau -\ln \left(1+\frac{ \tau
\displaystyle \sum _{k=-m}^m \gamma_{k}\,e^{ \,i\,k\,\varphi} }{h}
\right)
\end{aligned}$$
The group velocity can be expressed as
$$V_g = \frac{i \,\displaystyle \sum _{k=-m}^m i\,k
\,\gamma_{k}\,e^{\,i\,k\,\varphi } }{\omega \left(\frac{\sigma
\displaystyle \sum
_{k=-m}^m \gamma_{k}\,e^{\,i\,k\,\varphi } }{c}+1\right)}$$
from which it comes that
$$\label{rel}
\begin{aligned} \frac{{\partial } V_g }{\partial
{\varphi}}&= \frac{i \,c^2 \tau\, \left(\left(c+\sigma
\,\displaystyle \sum _{k=-m}^m \gamma_{k}\,e^{i\,k\,\varphi }
\right)
\displaystyle \sum _{k=-m}^m \, i\,k ^2 \gamma_{k}\,e^{i\,k\,\varphi } -\sigma \, \left(\displaystyle \sum _{k=-m}^m
\gamma_{k}\,e^{ i\,k \varphi } i\,k \right){}^2\right)}{\sigma \, \left(c+\sigma \,\displaystyle \sum
_{k=-m}^m \gamma_{k}\,e^{i\,k\,\varphi } \right){}^2}
\end{aligned}$$
Through identification of the real and imaginary part of (\[rel\]), we obtain:
$$\label{rel1} \sigma \, \displaystyle \sum _{k,l=-m}^m \,
\gamma_{k}\,\gamma_{i+l}\,\left \lbrace k^2 \sin \left [ \,(k+l)
\varphi \,\right ] -k\, l\, \cos \left [\,(k+l) \varphi\,
\right ]\right \rbrace =-c \, \displaystyle \sum _{k=-m}^m k^2 \,\gamma_{k}\,\sin (k \,\varphi
)$$
and
$$\label{rel2}
\sigma \, \displaystyle \sum _{k,l=-m}^m \gamma_{k}\,\gamma_{l}\, \left \lbrace -\,\cos \left [\,(k+l)\,
\varphi\right
]
-k\,l\,\sin \left [\,(k+l)\, \varphi \,\right ] \right \rbrace=c \, \displaystyle \sum _{k=-m}^m k^2 \,\gamma_{k}\,\cos (k \,\varphi
)$$
Due to (\[RelCoeffDRP1\]), (\[rel1\]) and (\[rel2\]) respectively become:
$$\label{rel1} \sigma \, \displaystyle \sum _{k,l=-m}^m \,
\gamma_{k}\,\gamma_{l}\,\left \lbrace k^2 \sin \left [ \,(k+l)
\varphi \,\right ] -k\, l\, \cos \left [\,(k+l) \varphi\,
\right ]\right \rbrace =-2\, c \, \displaystyle \sum _{k=1}^m k^2 \,\gamma_{k}\,\sin (k \,\varphi
)$$
]
-k\,l\,\sin \left [\,(k+l)\, \varphi \,\right ] \right
\rbrace=0$$
Denote by $T_j$, $j\in \N^*$ the Chebyshev polynomial of the first kind, and by $U_j$, $j\in \N^*$ the Chebyshev polynomial of the second kind:
$$\label{Tche1} \cos(j\,x)=T_j\left (\cos(x)\right )=\frac
{n}{2}\displaystyle \sum_{k=0}^{\big [ \frac {n}{2}\big ]}
(-1)^k\,\frac {(n-k-1)!}{ k!\,(n-2\,k)!}\,(2\,\cos(x))^{n-2k}$$
$$\label{Tche2} \sin(j\,x)=\sin(x)\,U_j\left (\cos(x)\right )$$
where: $$\label{Tche2} U_j\left (\cos(x)\right )= \displaystyle
\sum_{k=0}^{\big [ \frac {n}{2}\big ]} (-1)^k\,\frac {(n-k )!}{
k!\,(n-2\,k)!}\,(2\,\cos(x))^{n-2k}$$
$\big [ \frac {n}{2}\big ]$ denotes the integer part of $ \frac {n}{2} $.
Equations (\[rel1\]), (\[rel2\]) can thus be written as:
$$\label{rel1bis} \sigma \, \displaystyle \sum _{k,l=-m}^m \,
\gamma_{k}\,\gamma_{l}\,\left \lbrace k^2
\sin(\varphi)\,U_{k+l}\left (\cos(\varphi)\right ) -k\, l\,
T_{k+l}\left (\cos(\varphi)\right )\right \rbrace =-c \,
\displaystyle \sum _{k=-m}^m k^2
\,\gamma_{k}\,\sin(\varphi)\,U_{k}\left (\cos(\varphi)\right )$$
and
$$\label{rel2bis}
\sigma \, \displaystyle \sum _{k,l=-m}^m \gamma_{k}\,\gamma_{l}\, \left \lbrace T_{k+l}\left (\cos(\varphi)\right )
+k\,l\,\sin(\varphi)\,U_{k+l}\left (\cos(\varphi)\right )\right
\rbrace=0$$
Using the relation:
$$\sin(\varphi)=\sqrt{1-\cos^2(\varphi)}$$
equations (\[rel1bis\]), (\[rel2bis\]) can be written as:
$$\label{rel1ter} f_1\left (\cos(\varphi)\right )=0$$
and
$$\label{rel2ter}
f_2\left (\cos(\varphi)\right )=0$$
where, for all $\theta \in \R$:
$$f_1(\theta) =\sigma \, \displaystyle \sum _{k,l=-m}^m \,
\gamma_{k}\,\gamma_{ l}\,\left \lbrace k^2
\sqrt{1-\theta^2}\,\,U_{k+l}\left (\theta\right ) -k\, l\,
T_{k+l}\left (\theta\right )\right \rbrace \,+\,c \, \displaystyle
\sum _{k=-m}^m k^2 \,\gamma_{k}\,\sqrt{1-\theta^2}\,U_{k}\left
(\theta\right )$$
i.e.: $$f_1(\theta) =\sigma \, \displaystyle \sum _{k,l=-m}^m \,
\gamma_{k}\,\gamma_{ l}\,\left \lbrace k^2
\sqrt{1-\theta^2}\,\,U_{k+l}\left (\theta\right ) -k\, l\,
T_{k+l}\left (\theta\right )\right \rbrace \,+2\,c \, \displaystyle
\sum _{k=1}^m k^2 \,\gamma_{k}\,\sqrt{1-\theta^2}\,U_{k}\left
(\theta\right )$$
and
$$f_2(\theta) = \displaystyle \sum _{k,l=-m}^m
\gamma_{k}\,\gamma_{ l}\, \left \lbrace T_{k+l}\left
(\theta\right )
+k\,l\,\sqrt{1-\theta^2}\,U_{k+l}\left (\theta \right )\right \rbrace$$
Due to:
$$T_{j}\left
(1\right )=1 \,\,\, \forall\, j\in\N^*$$
it is worth noting that:
$$f_1(1) =-\sigma \, \displaystyle \sum _{k,l=-m}^m \,
\gamma_{k}\,\gamma_{ l}\, k\, l$$
and
$$f_2(1) = \displaystyle \sum _{k,l=-m}^m
\gamma_{k}\,\gamma_{ l}$$
The knowledge of the scheme coefficients $\gamma_{k}$, $k\in \{-m,m\}$, enables one to study their variations, and to determine wether the equations (\[rel1ter\]), (\[rel2ter\]) admit a solution. One can thus know wether $\frac{{\partial } V_g }{\partial
{\varphi}}=0$ admits real roots, i. e. wether the schema has spurious caustics.
Numerical application: the 3-points DRP scheme {#Example}
==============================================
The 3-points DRP scheme is given by:
$$\gamma_1= 0.63662$$
We thus have:
$$f_1(1) =-2\,\sigma \, \left \lbrace \gamma_1^2-\gamma_1^2\right \rbrace=0$$
and
$$f_2(1) = 2\, \left \lbrace \gamma_1^2-\gamma_1^2\right \rbrace=0$$
For the 3-points DRP scheme, the dispersion relation is:
$$\begin{aligned}
& \,e^{\,i\, \varphi } \left(-e^{-\eta_{\omega} \,\tau}+e^{i
\,\tau\, \xi _{\omega }}\right)+e^{i
\tau\,\xi _{\omega }} \left(-0.63662 +0.63662 \, e^{2\,i \,\varphi }\right)\, \sigma=0
\end{aligned}$$
which leads to:
$$\begin{aligned}
& e^{i
\,\tau\, \xi _{\omega }} =\frac{e^{\,i\, \varphi } \,e^{-\eta_{\omega} \,\tau}}{ \,e^{\,i\, \varphi } + 0.63662 \,\sigma\, (e^{2\,i \,\varphi }-1)}
\end{aligned}$$
It yields:
$$\begin{aligned}
& \xi _{\omega } =\frac{1}{\tau}\,\text{Arctan} \left [\frac {
- \left (1+ 0.63662
\,\sigma \, \right ) \,\sin(\varphi ) }
{1+\left ( 0.63662 \,\sigma -1\right )\,\cos (\varphi )
} \right ]
\end{aligned}$$
The derivative $\frac{{\partial } V_g }{\partial
{\varphi}}$ of the group velocity $V_g$ vanishes for $\varphi=0$, $\varphi=\frac{\pm\pi}{2}$, and $\varphi=0.950935$.
The 3-points DRP scheme admits thus spurious caustics.
We now illustrate the caustic phenomenon considering the two following sinusoidal wave packets:
$$\label{paquet1} u_1=e^{\,-\alpha\,
(x-x_0^1-c\,t)^2}\,\text{Cos}\,[\,k_1\,(x-x_0^1-c\,t)\,]$$
$$\label{paquet2} u_2=e^{\,-\alpha\,
(x-x_0^2-c\,t)^2}\,\text{Cos}\,[\,k_2\,(x-x_0^2-c\,t)\,]$$
where $\alpha>0$. The two wave packets are initially centered at $x_0^1$ and $x_0^2$, respectively. The group velocity of the two wave packets are $V_1 = V_g (k_1)$ and $V_2 = V_g
(k_2)$, respectively, where the function $V_g (x)$ is associated to the numerical scheme used to solve Eq. (\[transp\]).
If the solution obeys the linear advection law given by Eq. (\[transp\]), the initial field is passively advected at speed $c$, while, if the advection speed is scale-dependent (as in numerical solutions), the two packets will travel at different speeds, leading to the rise of discrepancies with the constant-speed solution. Another dispersive error is the shape-deformation phenomenon: due to numerical errors, the exact shape of the wave packets will not be exactly preserved. This secondary effect will not be considered below, since it is not related to the existence of spurious caustics. It is emphasized here that the occurance of spurious caustics originates in the differential error in the group velocity, not in the fact that shapes of the envelope of the wave packets are not preserved. The issue of deriving shape-preserving schemes for passive scalar advection has been adressed by several authors (e.g. [@leonard1; @leonard2]).
The spurious caustics will appear if the two wave packets happen to get superimposed. During the cross-over, the $L_\infty$ norm of the error (defined as the difference between the constant-speed solution and the dispersive one) will exhibit a maximum. The characteristic life time of the caustic, $t^*$, depends directly on the difference between the advection speeds of the two wave packets and the wave packet widths. Denoting $l_1$ and $l_2$ the characteristic length of the two wave packets, the time during which they will be (at least partially) superimposed can be estimated as
$$t^* = \frac{l_1 + l_2}{\vert V_1 - V_2 \vert}$$
It is seen that, since caustics are defined as solutions for which $\partial V_g / \partial k =0$, $t^*$ will be large if $
\vert k_1 - k_2 \vert \ll 1$. Noting $ k_1 = k_c + \delta k $ and $ k_2 = k_c - \delta k$, one obtains
$$t^* \simeq \frac{l_1 + l_2}{ 2 ( \delta k) ^2 \left| \frac{\partial
^2 V_g}{\partial k} (k_c) \right| }$$
leading to $t^* \propto ( \delta k ) ^{-2} $.
Neglecting shape-deformation effects and assuming that the numerical scheme is non-dissipative, the numerical error $E$ is given by:
$$\begin{aligned}
E = \vert & \, e^{- \alpha (x-x_0^1-c\,t )^2} \text{Cos} [
k_1\,(x-x_0^1-ct)\,] - e^{- \alpha
(x-x_0^1-t \,{V_1})^2} \text{Cos} [ k_1 (x-x_0^1-t {V_1})] \\
&+ e^{- \alpha (x-x_0^2-c\,t)^2} \text{Cos} [ k_2 (x-x_0^2-c t) ] -
e^{ - \alpha (x-x_0^2-t \,{V_2})^2} \,
\text{Cos}\,[\,k_2\,(x-x_0^2-t \,{V_2})\,] \vert
\end{aligned}$$
A simple analysis show that
$$\lim _{t \rightarrow + \infty} L_\infty ( E(t) ) = L_\infty ( u_1
(t=0)) , \quad \max _t L_\infty ( E(t) ) = 2 L_\infty ( u_1 (t=0))$$
The time history of the $L_\infty$ norm of $E$ for the 3-points *DRP* scheme scheme, is displayed in Fig. \[fig-error1\], showing the occurance of the caustic and the sudden growth of the $L_\infty$ error norm.
Figure \[CaustDRP3\] displays the isovalues of the residual kinetic energy for 3-points *DRP* scheme, for $cfl=0.9$. Minima are in black, maxima in white. In each case, the caustic corresponds to the white domain, where the residual kinetic energy is maximal.
\
Concluding remarks
==================
In the above, we have set a general method that enables one to determine wether a *DRP* scheme admits or not spurious caustics.\
The existence of spurious numerical caustics in linear advection *DRP* schemes has been proved. This linear dispersive phenomenon gives rise to a sudden growth of the $L_\infty$ norm of the error, which corresponds to a local focusing of the numerical error in both space and time. In the present analysis, spurious caustics have been shown to occur in polychromatic solutions. The energy of the caustic phenomenon depends on the number of spectral modes that will get superimposed at the same time. As a consequence, the spurious error pile-up will be more pronounced in simulations with very small wave-number increments. It has been shown that a popular existing scheme, as the 3-points *DRP*-scheme, allows the existence of spurious caustics.
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A polymer is a general term for any molecule that is a long string of smaller repeating parts. The difference between linear and branched polymers is based on their structure.
A polymer is a general term for any molecule that is a long string of smaller repeating parts formed by carbon-carbon bonds. The bonds can form long straight chains known as linear polymers, or parts can branch off from the chain, forming branched polymers. The polymers can also be cross-linked.
In manufacturing, polymers are often thought of as plastics because many artificial substances like plastics are polymers derived from petroleum. However, there are many different polymers (both naturally occurring and artificial) that are made of different parts. The way the units join together to form the polymer chain determines the polymer's properties along with its name. Polymers with different structures are named as linear polymers, branched polymers or cross-linked polymers.
Polymers are made from long, repeating chains of carbon-carbon bonds joining monomers, which are the smallest unique part of the chain. Many common polymers are made from petroleum and other hydrocarbons but others occur naturally. For example, artificial polyethylene is formed from a chain of ethylene molecules. Naturally occurring starch is made from long chains of glucose molecules. Some polymer chains are only a few hundred units long, while others have the potential of being infinitely long. For example, the molecules in natural rubber are so entwined that a whole rubber band can be considered one large polymer molecule.
The simplest polymer is a linear polymer. A linear polymer is simply a chain in which all of the carbon-carbon bonds exist in a single straight line. An example of a linear polymer is Teflon, which is made from tetrafluoroethylene. It is a single strand of units made from two carbon atoms and four fluorine atoms. When formed, these linear polymers can create strands of fibers or form a mesh that can be very strong and hard to break through.
Branched polymers occur when groups of units branch off from the long polymer chain. These branches are known as side chains and can also be very long groups of repeating structures. Branching polymers can be further categorized by how they branch off from the main chain. Polymers with many branches are known as dendrimers, and these molecules can form a webbing when cooled. This can make the polymer strong in the ideal temperature range. However, when heated, both linear and branched polymers soften as the temperature vibration overcomes the attractive forces between the molecules.
The cross-linked polymer forms long chains, either branched or linear, that can form covalent bonds between the polymer molecules. Because cross-linked polymers form covalent bonds that are much stronger than the intermolecular forces that attract other polymer chains, the result is a stronger and more stable material. An example of this is when natural rubber is vulcanized, which means it is heated so the sulfur molecules in the rubber polymer chains form covalent bonds with each other. This difference in strength is noticeable when you compare the stiffness, rigidity and durability of a car tire with that of a rubber band.
Carr, Kevin. "Difference Between Linear & Branched Polymers." Sciencing, https://sciencing.com/difference-between-linear-branched-polymers-8521652.html. 25 May 2018. | https://sciencing.com/difference-between-linear-branched-polymers-8521652.html |
Jiuzhaigou Sichuan Province, is approximate 250 miles (400 kilometers) north of Chengdu and is regarded by many as a fairy-world of mountains, great trees, wildlife, waterfalls, and stunning lakes. With the area of just over 23,000 square miles (60,000 square kilometers), the name of the park, Jiuzhaigou (“9 Village Valley,” “Dzitsa Degu” in Tibetan), is derived from the nine villages where Tibetans once lived near the ravine. Rising about 6,500 feet (2,000 meters) above sea level, Jiuzhaigou is covered by the dense virgin forest which is home to 108 lakes.
In 1992, the Jiuzhaigou National Park was named a UNESCO World Heritage Site and was given the status of UNESCO Man and Biosphere Reserve in 1997.
The beauty of Jiuzhaigou revolves around these lakes. The waterfalls cascade into a tranquil pond which make for a glistening turbulence. The scenic nooks in the waterfall are veiled by curtains of water.
In the 1970s, Jiuzhaigou was discovered by several lumberjacks by chance. In 1975, a team from the Agricultural Department made a comprehensive exploration and concluded that Jiuzhaigou is rich in wildlife, water, and minerals, and is a rare natural sight to boot.
With a forest covering over 7,700 square miles (20,000 square kilometers), Jiuzhaigou is the home to various types of wildlife. It shelters many kinds of rare and endangered animals like giant pandas, cloud leopards, lesser pandas, and golden cats. Jiuzhaigou also boasts a rich variety of flora with over 3,000 species and subspecies of trees and plants including more than 60 kinds of pine trees and 70 kinds of medicinal herbs.
The scenic area of Jiuzhaigou includes Baojingyan, Shuzheng, Rize, Jianyan, Changhai and Zharu, among which Rize and Shuzheng are the most famous. The Mirror Lake has more than 40 lakes which reflect light as well as mirrors. Shuzheng’s main scenery in Rize lies in the number of waterfalls such as Pearl Shoal Waterfall, Panda Waterfall, High Falls, and others. High Falls is the highest waterfall in Jiuzhaigou.
The main valley of Jiuzhaigou is Shuzheng, which is about 8.5 miles from the entrance of the valley to the Nuorilang Waterfall. Shuzheng Waterfall, Sparkling Lake, Tiger Lake, and many other small bodies of water are spread out across 3 miles of classical Tibetan villages.
In the same valley is Rhinoceros Lake, over a mile long, and 50 acres in size, and glistens in different shades of green during the summer months. If you look closely, you might be able to see the rhinoceros at the bottom of the 50-foot deep lake.
The main scenery in Shuzheng is Potted Landscape Shoal, Shuzheng Waterfall, and Reed Sea. At 8 and half miles (13.8 kilometers) long, Shuzheng is the gate of Jiuzhaigou, which is considered a miniaturized version of Jiuzhaigou.
The Zechawa, Rize, and Shuzheng Valleys all meet at the beautiful Nuorilang Waterfall, where you can also find local hostels and Tibetan restaurants. At more than 60 feet (20 meters) high and almost 1,000 feet across (300 meters), this impressive calcified geological feature is the symbol of Jiuzhaigou.
More than 11 miles long (18 kilometers), Zechawa Valley is the longest in the area at the south-eastern part of Jiuzhaigou. Long Lake can be found in this valley: enveloped by forested hills, it is incredibly photogenic with its azure blue waters formed from snow melt.
Nearby Five Color Pond is much smaller, but what it lacks in size it more than makes up for in sheer amazing displays of different colors ranging from pale blue to emerald green thanks to its varying depths and concentration of different minerals.
Rize Valley contains some of the most iconic spots in the greater Juizhai Valley. Tranquil Panda Lake is where pandas once came to drink of its blue-green waters, and is the only lake containing fish. like Five Color Pond, Five Flower Lake takes on a different shade depending on the angle at which you look at it.
Jiuzhaigou has four distinctive seasons with charming views, making just about any time of year and ideal time to pay a visit to the park. When bright blossoms erupt in spring, the whole of Jiuzhaigou bursts into color. In summer, Jiuzhaigou is veiled under the lush shady trees. Colorful lakes like pearls sparkle in the green. Jiuzhaigou presents another view in autumn when the leaves turn red and float on the lakes after falling from the trees. Jiuzhaigou in winter is covered by the snow, becoming even more tranquil and picturesque.
You can fly into Jiuzhaigou National Park from Xian, Chengdu, Beijing, or Shanghai, or take one of several bus routes. No trains go through Jiuzhaigou, however.
High-quality hotels can be found just outside the park such as the Sheraton Resort, InterContinental Resort, Hilton Resort, and others which typically meld-traditional Tibetan-style residences with modern facilities. Thankfully, most hotels make electric blankets available for those colder nights.
The valley entrance to Jiuzhaigou itself is roughly 6,500 feet above sea-level, so during any stay in Jiuzhaigou, take measures to prevent altitude sickness. This means avoiding strenuous activity and not consuming excessive amounts of alcohol. If you experience heart palpitations and a headache, seek medical attention.
Admission Fee: 220 RMB (from Apr. 1st to Nov. 15th ); 80 RMB (from Nov.16 to Mar.31 of the following year). Discounts on the entry fee are offered to those 6 to 18 years old, and those between 60 and 70. Children under 6 and seniors over 70 can enter the park for free. Visitors are required to take the Jiuzhaigou sightseeing Bus in the aftermath of a serious earthquake which shook the region in August 2017. The bus ticket costs 90 RMB. | http://www.chinatour.com/china-guide-and-tools/china-landmarks/jiuzhaigou-national-park/ |
The Chuburna House is a very straightforward contemporary residence located in a secluded spot in the coastal town of Chuburna, along the coast of Yucatan, Mexico. It was designed by Cabrera Arquitectos and it comes with a very simple construction, yet one that perfectly appeases the contemporary principles of minimalism and simplicity. The contemporary box shape of this home carries on to the interiors through large openings that expose its open floor plan layout.
A simple volumetric concrete located in a secluded and quiet beach on the Yucatan coast. This house, located in an area of low density is planted next to other buildings and within a predominant dune area on the turquoise beaches of the west coast of the port of Chuburna, as a large box of polished concrete that thanks to its cold volume, Sober and with a very strong tectonic presence, it becomes an architectural reference in the profile of the coast.
Thanks to the luminosity of its windows, light penetrates the house in a subtle and controlled manner, allowing the ground floor areas to have a unique atmosphere and invite relaxation, reading and meditation. In the upper part the window that is spoken in the room area becomes an instrument of visual communication with the outside to be able to contemplate the immensity of the sea.
The interior has a fairly simple decoration, the taste for Yucatecan crafts, the colors and textures and the architecture of the house make it an ideal architectural space to relax and disconnect from the world. Thinking that the most important thing is space and light, we have opted for neutral gray colors of polished concrete, both in floors and walls and the white color as a light screen on the soffits of the house. This makes a very integral contrast with the wood that appears everywhere, in details, furniture and doors.
The living room, the dining room, the kitchen and the terrace are a single space that has a small double height that integrates spatially the ground floor as the top floor and serves as a space and filter distributor to put overhead light of some grooves in the ceiling superior of the atrium.
Next to it, and without any separation, is the dining area. An area that I found especially attractive despite its simplicity thanks to the glass that surrounds the space and allows you to see the beach and the sea in the background while you are eating.
In front, and without any separation, is the pool. This area is the public heart of the house especially attractive because it integrates completely with the public spaces of the interior, its simplicity allows you to see the beach and the sea in the background while you are in the pool, resting or contemplating the exterior landscape from the dining room, you can Also enjoy this transparency since you enter the house and never lose direct contact with the beach.
The kitchen, also integrated in that unique space on the ground floor without divisions, and in which the simplicity of the space stands out, a concrete bar virtually divides the space with the dining room and the use of pasta floor tapes give it a special design touch.
In the upper part and around the double height a distributor hall is developed where it connects with a study that turns into an alcove with a view to the south, and also the circulation generates a very useful workspace for the owners.
The rooms follow the same decorative style, simple and natural that in the rest of the house, with shortage of furniture, large presence of wood, large windows to put the landscape inside the house and allow us to wake up with the sea as a backdrop background, and the bathroom again in a subtle way is integrated into the same bedroom.
Finally, its habitable rooftop works as a viewpoint in this fantastic place and as a detail of integration the land in the beach area is delimited with a very typical “albarrada” of the rural area of the state of Yucatan. | https://www.architectureartdesigns.com/chuburna-house-by-cabrera-arquitectos-in-chuburna-mexico/ |
This chapter discusses numerical methods for finding eigenvalues. However, to do this correctly, you must include numerical analysis considerations which are distinct from linear algebra. The purpose of this chapter is to give an introduction to some numerical methods without leaving the context of linear algebra. In addition, some examples are given which make use of computer algebra systems. For a more thorough discussion, you should see books on numerical methods in linear algebra like some listed in the references.
Let A be a complex p × p matrix and suppose that it has distinct eigenvalues
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and that
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with J1 an m1 × m1 matrix.
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where Nkrk≠0 but N krk+1 = 0. Also let
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Now fix x ∈ Fp. Take Ax and let s1 be the entry of the vector Ax which has largest absolute value. Thus Ax∕s1 is a vector y1 which has a component of 1 and every other entry of this vector has magnitude no larger than 1. If the scalars
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||(14.1)|
Consider one of the blocks in the Jordan form. First consider the kth of these blocks, k > 1. It equals
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which clearly converges to 0 as n →∞ since
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where limn→∞en = 0 because it is a sum of bounded matrices which are multiplied by
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where En → 0,en → 0. Let
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However, this is an eigenvector because
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Here ≈ means “approximately equal”. However, there is a more convenient way to identify the eigenvalue in terms of the scaling factors sk.
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Pick the largest nonzero entry of w, wl. Then for large n, it is also likely the case that the largest entry of wn will be in the lth position because wm is close to w. From the construction,
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In other words, for large n
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Therefore, for large n,
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and so
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But limn→∞
This has proved the following theorem which justifies the power method.
Theorem 14.1.1 Let A be a complex p × p matrix such that the eigenvalues are
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with
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where s1 is an entry of Ax which has the largest absolute value. If the scalars
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where sn is the entry of Ayn−1 which has largest absolute value. Then it is probably the case that
In summary, here is the procedure.
Finding the largest eigenvalue with its eigenvector.
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where sk+1 is the entry of Auk which has largest absolute value.
Example 14.1.2 Find the largest eigenvalue of A =
You can begin with u1=
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Divide by the largest entry to obtain a good aproximation.
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Now begin with this one.
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Divide by 12 to get the next iterate. | https://klkuttler.com/books/Linearalgebra/x1-14800014.1 |
"Laces Out"
Settings
Location
(All)
Lowry CrossFit
Program
CrossFit
CrossFit SATURDAY
Date
WOD
MONDAY 6.29.20 - Lowry CrossFit
Class
(All)
6:00 AM CrossFit
7:30 AM CrossFit
9:00 AM CrossFit
12:00 PM CrossFit
4:15 PM CrossFit
5:30 PM CrossFit
6:45 PM CrossFit
Age Group
All Ages
0 - 17
18 - 24
25 - 34
35 - 44
45 - 54
55 - 64
65+
Count (M/F):
11 (6/5)
WOD
MONDAY 6.29.20
Please continue to schedule classes on the wodify app. Thank you.
WU:
5 Minutes.
2 Snatch Drops
2 Tall Snatches
Set 1: Empty Barbell
Set 2: 35% of 1RM Snatch
Sets 3-5: 40-50% of 1RM Snatch"
STIMULUS
DESCRIPTION
The first part of todays Snatch Technique work will train us to get under the bar quickly
We're repeating this piece from last week with the intention of increasing weight slightly in sets 3-5
Both movements start at full extension and focus on a fast, aggressive drop
Note that there is no dip and drive with the legs to elevate the bar - the only motion is down
These loads are designed to be very light, so adjust percentages as necessary
1: Metcon (Weight)
Snatch Complex
On the 2:00 x 5 Sets:
1 Low Hang Power Snatch
1 Power Snatch
1 Low Hang Squat Snatch
1 Squat Snatch
Set 1: 63% of 1RM Snatch
Set 2: 66% of 1RM Snatch
Sets 3-5: 69% of 1RM Snatch
STIMULUS
DESCRIPTION
This piece is also a repeat, as we climb 3% over last week
The focus of this piece is to keep the bar close to the body as your navigate the knees
These 4 reps are designed to be completed without letting go of the bar
""Low Hang"" is defined as just below the knee
1: Front Squat (10-8-6-4-2)
On the 3:00 x 5 Sets:
Set 1: 10 Reps @ 63%
Set 2: 8 Reps @ 68%
Set 3: 6 Reps @ 73%
Set 4: 4 Reps @ 80%
Set 5: 2 Reps @ 88%
STIMULUS
DESCRIPTION
Also climbing 3% over last week in this Front Squat piece
The reps will decrease as the loading increases in this running clock workout
You'll start a new set every 3 minutes [0-3-6-9-12]
This format ensures you have adequte rest between efforts
These sets are designed to be completed unbroken, so adjust percentages as needed based on feel
MC: "Laces Out" (AMRAP - Rounds and Reps)
AMRAP 18:
6 Bar Muscle-ups
9 Push Presses (135/95)
15 Deadlifts (135/95)
21 Wallballs (20/14)
STIMULUS
DESCRIPTION
Combining gymnastics and weighlifting in this longer AMRAP workout
With each station, we'll alternate between pulling and pressing movements
Choose weights and variations that allow you to complete 4+ rounds today
This works out to a round at least every 4:30
BAR MUSCLE-UPS
If you have over 9 unbroken bar muscle-ups when fresh, let's complete this station as written
If you're not quite there, consider reducing the reps [3-5] or choose a substitution from the list further down the page
BARBELL MOVEMENTS
Pick your barbell weight based off the push press, as it is the more challenging of the two at this weight
Use a load that you can complete the 9 push presses within 2 sets during the workout
WALLBALLS
Use a weight that you could complete for 30+ reps unbroken when fresh
Men throw to a 10ft. target
Women throw to a 9ft. target
SUBS
BAR MUSCLE-UPS
Reduce Reps
Jumping Bar Muscle-ups
Banded Bar Muscle-ups
12 Chest to Bar Pull-ups
15 Pull-ups "
Want to see some of these movements in action? Check out our
video library
.
Whiteboard:
Monday, June 29, 2020
Male Athletes
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Action
Jackson
4:15 PM CrossFit
175 lbs
2
Ben
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135 lbs
4
Joe
Espinoza
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Chris
Benedict
5:30 PM CrossFit
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6
Josh
Randels
4:15 PM CrossFit
110 lbs
Female Athletes
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Erin
Bonthron
5:30 PM CrossFit
105 lbs
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Chelsea
Morgan
5:30 PM CrossFit
80 lbs
3
Liz
Salisbury
12:00 PM CrossFit
75 lbs
4
Melissa
Wood
7:30 AM CrossFit
60 lbs
5
Alysia
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12:00 PM CrossFit
35 lbs
Trainer bar
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With death toll rising from the devastating typhoon in the Philippines this week, it seems that we’re constantly being reminded of the destruction of natural disasters, especially for rural and poor areas. Rural communities can be difficult to reach in times of environmental chaos, and poorer regions don’t always have the resources to cope with a crisis. When city services shut down or relief aid doesn’t come through immediately, community members band together to manage the aftermath of the disaster as best they can.
Sociologist Eric Klinenberg believes that community resources including “public places from libraries to mom-and-pop shops and coffee shops” can influence the outcomes of a crisis by providing the community the familiarity and support they need. In researching one such disaster, the 1995 Chicago heat wave, Klinenberg found that the residents of neighborhoods with more social infrastructure—like libraries and coffee shops—fared much better during the heat.
Those resources so dramatically improve the quality of our life on a regular day, but when there’s a heat wave or a hurricane or some other disaster, they can make the difference between life and death. In the Chicago heat wave, they did.
These types of social infrastructure benefit communities beyond times of crisis, according to Klinenberg who argues,
The nice thing about investing in climate security through social infrastructure is that the residual benefit is that we could dramatically improve the quality of life in these places all the time regardless of the weather. And it’s that kind of intelligent design that we desperately need at this moment. | https://thesocietypages.org/clippings/2013/11/15/libraries-coffee-shops-and-natural-disasters/ |
Musician Ilayaraja is the one who has bound today’s generation with his music. He made his cinematic debut in 1976 with the film Annakkili and has consistently composed music for over 1000 films. Ilayaraja has worked as a composer in various languages besides Tamil and has won 5 national awards.
He has so much pride, he is always outspoken. In many cases, his actions have been shown to be arrogant. Copyright bought the song a few years ago so that no one could sing the songs he composed. It caused a great deal of controversy.
Some celebrities have said that he has a character that does not belong to anyone. The musician has always had respect for only one person to be like this. Musician Ilayaraja has used the melody king Mr. MS Viswanathan as his guru.
Ilayaraja, who has always had respect for him, once met him at a house party. When he saw the melody king, he fell at his feet and worshiped the musician. This act has come as a surprise to many who have seen it.
Despite his many criticisms, he is at such a high ebb because of his respect for the Guru. The music of this film is still very popular today. In this musical, AR Rahman has worked as a keyboard player.
Ilayaraja, who is currently working on a lot of films, is conducting music concerts. He last composed music for the Hindi film Happy in 2019. It is noteworthy that MSV last had a natural disaster in 2015.
View uncensored news and videos on CinemaPad YoutubeSubscribe on. | https://mpmcorner.com/entertainment-world/ilayaraja-who-does-not-respect-anyone-will-only-submit-to-him-the-incident-of-falling-at-his-feet-and-worshiping/ |
Exciting postdoctoral training opportunity developing novel influenza vaccines at the University of Chicago We are seeking a Postdoctoral Fellow to...
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Postdoctoral Fellow
A postdoctoral position is immediately available for a highly motivated upcoming or recent Ph.D. or M.D./Ph.D. graduate in the field of optogenetics
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A Postdoctoral Scholar position is available in the laboratory of Dr. Senthil Radhakrishnan in the Department of Pathology at Virginia Commonwealth...
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Postdoctoral Associate (Immunology and Cancer Research)
Conducts experiments in a research laboratory studying the innate immune regulator STING and its role in influencing inflammatory disease and cancer.
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Postdoctoral Fellowship Position, Microbiome and Cancer
We have an opening for a postdoctoral fellow to join a translational prostate cancer research team at the Johns Hopkins University School of Medicine.
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Join the laboratory of Dr. Panos Z. Anastasiadis at the Mayo Clinic in Florida, a highly collaborative and dynamic research environment, with a str...
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Radiation Oncology Postdoctoral Fellowship
Work with a team of biologists, physicians, physicists to evaluate a revolutionary new technology in delivery of particle beam (Proton) radiotherapy.
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Postdoctoral Fellow in Cancer Biology
Seek a highly qualified individual to examine the mechanisms that control cell cycle and genomic stability.
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Dr. Pamela Munster seeks a Post-doc for her UCSF lab to explore cancer epigenetics and immunology as therapeutic targets to treat BRCA-like cancer.
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ITMO University’s Laboratory of Solution Chemistry of Advanced Materials and Technologies is looking for a Postdoc Researcher in Molecular Oncology.
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Postdoctoral Research Fellow- Cancer Biology
Applications are currently being accepted for a postdoctoral fellow to join the laboratory of Khashayar Vakili at Boston Children’s Hospital/Harvar...
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Investigating drug resistance and metastases of breast cancers, and validating novel therapeutic approaches using patient-derived tumor models.
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The Sheltzer Lab at Cold Spring Harbor is seeking postdoctoral researchers for a funded project identifying novel cancer drug targets.
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Post-doctoral fellows Georgetown University’s Lombardi Comprehensive Cancer Center is currently recruiting talented scientists for post-doctoral fe...
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Postdoctoral Fellow in Computational Biology
Exciting computational biology postdoc opportunities with a focus on genome engineering and cancer research.
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We are looking for highly motivated candidates with a Ph.D. within last three years in cellular and molecular immunology with an emphasis on the ca...
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Post-Doctoral Associate
Dr. Scott Dehm at the Masonic Cancer Center, University of Minnesota is currently seeking exceptional and creative scientist for POST DOC ASSOC.
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postdoctoral scholar
Postdoctoral position in basic and translational cancer biology at the UCSF Helen Diller Family Comprehensive Cancer Center.
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Postdoctoral Position, Molecular Biology, Translational Science, Penn State University
Postdoc position on RNA biology and translational musculoskeletal research, focusing on the molecular basis of obesity/T2D-associated bone diseases.
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Postdoctoral Research Position: Focus on Immunotherapy of Leukemia
Postdoctoral positions with focus on Immunotherapy of Leukemia at Johns Hopkins University School of Medicine. | http://jobs.sciencecareers.org/jobs/cancer-research/academia/postdoc-fellowship/ |
This is the third in a series of blog posts on the role Twitter plays in scholarly communication by, scientometrics researcher, Stefanie Haustein.
It’s in the content and context of tweets that we can often find the most meaning. Unfortunately, most altmetrics research has analyzed counts and correlations rather than tweet content. In this post, I continue to analyze Altmetric data to explain how retweets and hashtags can help us better understand the degree to which users are engaging with research on Twitter.
Of the studies looking at tweet content, one found that the majority contained the title of the article it linked to or summarized it briefly. Another reported that sentiment was mostly absent, and, although most tweets were neutral, the share of positive and negative tweets differed between disciplines. A number of studies focused on analyzing the use of Twitter specific affordances, such as retweets (RTs), user mentions (@mentions) and hashtags (keywords following #). These functions were co-created by users and developers to facilitate communication on Twitter. Studies analyzing affordance use among scholars compared different types of users, disciplines and personal and professional use. They found, for example, that the majority of tweets sent by astrophysicists were conversational, as 61% were retweets, @replies or @mentions. Most of these mentions referred to Twitter accounts of science communicators, other astrophysicists or organizations. Similarly, 72% of tweets sent by Canadian doctoral students in the social sciences and humanities contained other user names, while conversational tweets were less likely to contain URLs. While retweets and tweets with hashtags or links were mostly of professional nature, @mentions appeared more often in US professors’ tweets classified as personal, which suggests that when professors discuss their work, they are less likely to address other users than when they tweet about private matters. In fact, more than 90% of @mentions functioned to address another user, while 5% worked as a reference (Honeycutt & Herring, 2009).
Tweet, tweet, retweet
Retweets are not original contributions to discourse on Twitter, but they do have unique meaning. Like most Twitter affordances, retweets originated within the Twitter user base to facilitate forwarding messages and was only later integrated by Twitter developers in form of the retweet button. Retweets have been described as “internal citations” and, since users forward tweets sent by others, they represent a specific form of information diffusion. Once common in many Twitter bios, the disclaimer, “retweets do not equal endorsements” emphasizes that retweets are diffusing rather than advocating tweet content. Studies examining academics’ Twitter use found that retweeting was less common than other affordances among a group of astrophysicists or that US professors were more than twice as likely to retweet when tweeting professionally. Researchers were more likely to retweet tweets containing links but links to papers—such as those captured by Altmetric—were less likely to be retweeted by a group of 28 scholars.
Nevertheless, the analysis of Altmetric Twitter data shows that retweeting seems to be particularly popular on academic Twitter: Half of the 4 million tweets linking to 2015 WoS papers were retweets (see table below). This suggests that a significant amount of academic tweeting activity focuses on information diffusion, which does not involve much engagement. After all, it only takes the click of a button to retweet another user’s post.
A 50% retweet rate is particularly high when compared to general Twitter users (3%) and also exceeds other studies investigating academic users (between 15% and 37%). It should be noted that general Twitter use analyzed by boyd was based on a random sample of tweets collected in 2009. Among journals with more than 10,000 users tweeting their 2015 articles, the percentage of retweets ranges from 47% for PLOS ONE to 70% for PLOS Biology (see table above). It is also interesting to note that the most active users (based on number of tweets linking to the journal’s articles) often include the journal’s official Twitter account (marked in bold in the table). We will look into who is tweeting scholarly articles in the last post of this mini series.
As we have already seen in the previous blog post, the table above highlights that biomedical journals are particularly popular, as demonstrated by a high Twitter coverage and average number of tweets per document. With retweets exceeding the number of original tweets per scientific specialty, retweeting was particularly common in Miscellaneous Zoology, General & Internal Medicine, Miscellaneous Clinical Medicine and Ecology. At less than 20%, publications in Solid State Physics, Inorganic & Nuclear Chemistry, Chemical Physics and Applied Chemistry were least likely to be retweeted. Comparing the share of retweets with Twitter coverage for 2015 publications per field, retweets are less common in disciplines with low Twitter activity, which suggests that users in these fields do not tweet as much to diffuse others’ information, possibly because they are not well connected.
Japanese tweet on mental health and Fukushima study most retweeted
The most retweeted tweet captured by Altmetric until June 2016 was sent by@takebata, a professor at the University of Hyogo in Japan. It was retweeted 7,126 times by 7,057 users and written in Japanese, allowing for more detailed discussions than languages using Latin characters. The tweet linked to a study in the Community Mental Health Journal showing that giving 50 Euros per month to mental health patients in Sweden significantly improved their depression, anxiety and social life.
The most retweeted scholarly article, regardless of who sent the original tweet, appeared in Nature’s Scientific Reports and demonstrates the nuclear contamination of freshwater fish by the Fukushima accident. The publication was retweeted 15,768 times, 45% of retweets were received by 366 tweets sent by @Lulu__19. Her tweets were also written in Japanese and most retweeting users were from Japan, which is not surprising given that Twitter is the country’s most popular social media platform.
Tweets with conference hashtags enable backchannel discussions
Hashtags enable exchanges among Twitter users with common interests, regardless of whether they follow each other (e.g. #academicswithdogs). They thus allow macro-level communication among users. In academia, hashtags are commonly used at conferences. Tweeting at scholarly conferences has been one of the earliest and most popular uses of Twitter by academics, maybe because tweeting fosters communication among people participating in shared experiences. Almost every scientific conference today has a specific hashtag to connect attendees and remote participants, who are not able to attend in person (e.g., #5amconf and #altmetrics15). Apart from increasing the visibility of conference presentations, tweeting at scientific meetings has introduced another level of communication, creating backchannel discussions online. Due to the ease of collecting tweets with a particular hashtag, there are countless studies on tweets analyzing scholarly Twitter use based on tweets with conference hashtags.
Hashtags seem to be less popular among academics on Twitter, maybe because they are less familiar with this feature or they do not wish to expand conversations beyond their personal publics established through their follower networks. Sixty-one percent of surveyed professors rarely or never used a hashtag, while around a quarter of astrophysicists’ as well as Canadian PhD students’ tweets by contained a hashtag. Inferring hashtag use from most other studies is not possible, as data collection itself is often based on specific hashtags.
#science, #cancer, #physics are most popular hashtags
Just below one third of the 24.3 million tweets in the Altmetric database file made available to researchers contained a hashtag. This hashtag use is much higher than the 5% of a random sample of tweets analyzed by boyd and colleagues, but is comparable to other studies on academic tweets. 401,287 unique hashtags were mentioned 12.6 million times, which amounts to a mean occurrence of 31 hashtag uses per unique term (see table below), but since hashtag frequency is extremely skewed, the standard deviation is high and the median hashtag frequency is as low as only 2. The most popular hashtag occured 162,754 times, while 169,992 hashtags were used in one tweet only. As few as 3% of hashtags make up 80% of occurrences with #science (1.3% of hashtag occurrence), #cancer (0.9%), #physics (0.8%), #openaccess, #health (0.7% each), #paper, #oa and #research (0.5% each) appearing most frequently. The occurrence of #oa as well as #openaccess among the most frequent hashtags reflects the known heterogeneity of folksonomies and the need for tag gardening, where tags with different spellings and abbreviations are combined.
Hashtag use is extremely skewed
We also studied a subset of Web of Science articles published in 2015 when analyzing Altmetric’s data. These Web of Science articles were described using 105,705 unique hashtags, with 6% of all hashtags representing 80% of hashtag uses. Each hashtag was mentioned on average 21 times (mean; median: 2) for a total hashtag frequency of 2.2 million. While 33% tweets contained a hashtag, 46% of all tweeted about articles were described with at least one hashtag. Articles were most frequently tagged with #cancer (1.0%), #health, #openaccess, #science (0.9% each), #FOAMed, #Diabetes, #ornithology and #Psychiatry (0.6% each).
The figure on the right demonstrates (A: for all documents in the Altmetricdata dump; B: Web of Science articles published in 2015) the number of tweets containing a particular hashtag and the number of distinct users mentioning it on a log-log scale. While in general, a log-linear relationship can be found between the number of occurrences and users, a few popular hashtags are tweeted by a limited number of users, which suggests a small but active group of users. The number of users, documents and journals associated with a hashtag can provide information as to how general and widespread a hashtag is, or how specific and relevant to only a small community.
#StandWithPP, #Fit, #dataviz and #coffee most widely spread hashtags
Looking at the number of unique users per hashtag, the largest discrepancy (among hashtags occurring at least 1,000 times) can be observed for #genomeregulation (1,924 tweets; 10 users), #eprompt (2,281; 17) and #cryptocurrency (4,515; 38), which were, on average, tweeted by the same users more than 100 times. On the contrary, the user-hashtag ratio was lowest for #Fit (4,818; 4,743), #StandWithPP (Stand with Planned Parenthood; 1,060; 972), #dataviz (1,010; 912), #coffee (1,517; 1,246, see figure above), and #PWSYN (The Patient Will See You Now; 1,017; 834), which indicates a widespread adoption among Twitter users. Accordingly, these hashtags point to more general, less scientific topics.
How do these findings influence metrics?
When analyzing the Twitter impact of scholarly publications, the way in which they are tweeted should be taken into account. Namely, we should be careful to remember that Twitter is primarily used as a mechanism to diffuse, rather than engage with, research.
The fact that half of all tweets were not original contributions and only involved minimal user engagement—clicking the retweet button—suggests that most tweets simply spread the word about scientific articles, rather than contribute to debate or endorsement of research. Intense discussions about research are the exception rather than the rule. Admittedly, 140 (or, more recently, 280) characters do not provide too much room for in-depth discussions.
The hypothesis that Twitter users diffuse rather than engage with scholarly documents is further supported by the studies that showed that most tweets contain article titles or short summaries and no sentiments. Scholarly Twitter metrics should thus distinguish between different levels of engagement—diffusion, discussion, appraisal—or at least identify the share of original tweets and retweets.
Hashtags are a powerful Twitter feature that enable the exchange among users beyond follower networks. It can be argued that hashtag terms carry special meaning, because they connect users interested in the same topic or event and play a central role in retrieving relevant tweets. Even if statistics on hashtag frequency—particularly in combination with other Twitter data—can reveal some information about how users are tweeting, a qualitative analysis of hashtags is much more meaningful. Provided adequate tag gardening combining various spellings of the same concept, hashtags offer a crowdsourced view on tweet content—and by extension article content—and the context in which scholarly documents are shared on Twitter. Hashtag analysis thus represent a first step towards content analysis and helps to move away from simple counting of mentions towards contextual interpretation of altmetrics data.
Stefanie Haustein is assistant professor at the University of Ottawa’s School ofInformation Studies, whereshe teach research methods and evaluation, social network analysis and knowledge organization. Her research focuses on scholarly communication, bibliometrics, altmetrics and open science. Stefanie co-directs, together with Juan Pablo Alperin, the #ScholCommLab, a research group that analyzes all aspects of scholarly communication in the digital age. Stefanie’s publications can be found on her website. She tweets as @stefhaustein. | https://www.altmetric.com/blog/rt-plosone-cancer-health-openaccess-or-how-scholarly-papers-are-diffused-on-twitter/ |
What are the Mathematics Achievements of the Mongolians?
The Mongolians have done a lot of research on mathematics. The first to study Euclid’s “Elements of Geometry” was Meng Ge. According to records, “The Genghis Khan kings Yimengge are more knowledgeable, and Bizhi explained some of the schemes of Euclid.”
In the early eighteenth century, Ming Antu, a Mongolian scientist who served at the Qintian Supervisor of the Qing Dynasty, made great contributions to mathematics. At that time, three analytic formulas related to trigonometric functions were imported from Europe, but they were not proved.
Mingan Tu “pity only has its method, but did not elaborate its meaning”, so he spent 30 years on research, not only created the “cut circle and connected proportion method” to prove three formulas, but also obtained six analysis independently. formula. The mathematics research manuscript left by Ming Antu was later compiled into a book by his son Ming Xin, students Chen Jixin, and Zhang Liangting, and was inscribed in a 4-volume mathematics monograph “The Method of Cutting the Circles, Secrets, and Shortcuts.”
“Circle cutting” refers to dividing the circumference into equal parts, or dividing the arc length in the circle into several equal parts, and then using the cutting circle method to find the circumference or the arc length in the circle.
This value is very close to the actual value, and it can also be said to be an approximation of the pi. “Quick method” refers to a method that can be easily and quickly calculated. In this book, he not only rigorously proved the correctness of the three infinite series passed in from the West, and deduced the three “circle diameter seeks the circumference”, “the arc back seeks the sine”, and “the arc back seeks the sine”. 6 formulas, and 6 infinite series were discovered and demonstrated, and 6 formulas that surpassed the world scientific level at that time were created, namely, the arc back seeks the string, the arc back seeks the vector, the string seeks the arc back, the sine seeks the arc back, The positive vector seeks the arc back, the vector seeks the arc back.
In proving these nine formulas, he created four formulas: cosine and cosine for cosine and sine, cosine and cosine for the original arc, sine and cosine by arc back, and sine and cosine for arc back by sine and cosine. The “method of cutting circles and connecting proportions” created by him contains the advanced ideas of the combination of figure and number and the mutual transformation of straight lines and arcs. This idea of finding a circle with a straight line and finding a straight line with a circle has the same meaning as Western calculus. It was a relatively advanced idea in the world of mathematics at that time.
Therefore, Mingantu is regarded as the pioneer of calculus and the pioneer of advanced mathematics in our country, and has made significant contributions to the development of mathematics in our country.
The Mongolian people who study mathematics and have written works for later generations are not only Ming Antu alone, but also Dulun in the late Qing Dynasty. Du Lun authored a volume of “Yi Liao Da Fang Shu Cao”, also known as “Shao Guang Zhang Chu Bian”, the content belongs to elementary mathematics.
Cut circle ratio
It is the geometric basis of the series theory in the Qing Dynasty. It was first clarified by Ming Antu in “The Method of Cutting the Secret Rate and Shortcut”, and it was later improved by the work of mathematicians such as Xiang Mingda and Dong Youcheng. . The central problem of cutting circle connection ratio is how to find the length of the arc when the arc length is known, how to find the length of the chord and the height of the vector, or how to find the length of the arc when the length of the chord and the height of the vector are known.
The method of cutting the circle and connecting the center of the proportion is to combine the method of connecting the proportion introduced from the West and the traditional Chinese calculation method to divide the arc into multiple equal parts, draw multiple vectors, and then construct a series of similar triangles to obtain a series of continuous proportions. , And then divide the arc to be thinner, and use a broken line to approach the arc to obtain the arc length.
Mingantu also proposed four formulas that use cosines, cosines, and cosines to simplify calculations with the help of trigonometric transformations. At the same time, it also solves the calculations of cosines and arccosines. Volume 2 “Usage” is the use of each formula in mathematics and astronomy Application examples include the calculation of trigonometric function values such as sine and cosine, the solution of plane and spherical triangles, the calculation and conversion of the right ascension, declination and yellow longitude of Venus, and the calculation and conversion of yellow latitude. | https://ninenovel.net/2021/06/09/what-are-the-mathematics-achievements-of-the-mongolians/ |
It’s been 34 years, an entire generation, since the US government’s chief climate scientist warned Congress that the planet was warming with potentially catastrophic consequences. It’s already happening now. It’s time to stop the bullshit,” Dr. James Hansen said in his 1988 testimony. Scholars have since struggled to communicate this to the public and government officials.
Scientists and their translators explained that pollution from the combustion of fossil fuels collects above the Earth, acting like glass in a greenhouse and carrying the sun’s heat close to the planet’s surface – the “greenhouse effect”. Or they described the gases as an invisible mantle covering the Earth and getting thicker with every ton of carbon dioxide (CO2) emitted by civilization.
But before metaphors and analogies explain climate change, the public should be open to hearing about it. Unfortunately, the letter is not good news. Many people with the power to do something about global warming haven’t listened to it because it’s easier to deny a harsh truth than to fix it.
Those of us who try to break through the communication barrier on climate change focus on that crisis and fail to point out an even harsher truth: climate change is just one manifestation of humankind’s harmful effects on nature. What’s really at risk is the biosphere – the atmosphere, the hydrosphere (oceans), and the lithosphere (the Earth’s hard surface). These are the places where all life on this planet exists, working together like organs in our bodies.
The best metaphor for this is the popular Jenga game. Players build a tower of blocks, then take turns removing them one by one. The loser is the person who removes the block that brought down the tower.
With industrialization and population growth, civilization has been pulling blocks from the Jenga Tower for centuries, including many elements vital to the integrity of the structure. The inconvenient truth that not many people want to accept or even hear is that the hospitable land we knew 10,000 to 12,000 years ago is on the verge of collapse.
A few years ago, the Stockholm Center for Adaptation at Stockholm University met with 28 renowned scientists to identify “safe operating spaces” on the planet that humanity cannot cross without causing large-scale, sudden and irreversible changes in the biosphere. The team came up with nine critical spaces. Only one is climate change. Other factors include ocean acidification, ozone layer depletion, changes in land use, and loss of fresh water.
Geologists believe that man’s influence on the biosphere is so extensive that it created a new era in the planet’s 4.5 billion year history. They have suggested calling it the Anthropocene, a term indicating that the human race is now the most influential and destructive force on Earth. The evidence, which ranges from plastic pollution to the fallout from nuclear weapons tests, reads like an indictment of modern civilization because that’s what it is. Humanity is on trial, with little time left to fix things before judgment is passed and the planet imposes the harshest punishment.
We must answer some questions if we are generous enough to care about the future. What happens if we remove the biodiversity block, the freshwater block, or the fertile soil block? What if we removed the blocks representing the carbon and water cycles on Earth or the chemistry of the oceans? In this regard, how many blocks do we dare to add to the top of the tower to represent the growth of the population?
If the US Congress, other world leaders, and the general public had heeded Hansen’s warning about climate change 34 years ago, we could have made the necessary corrections with minimal cost and disruption. Instead, the use of fossil fuels over the past three decades has thickened the cap, while urbanization, agriculture, deforestation and pollution have brought us closer to the limits of the planet.
The Jenga tower sways as we carelessly remove its mass. Its destabilization is so gradual that we are not shocked. But all life will suffer when it collapses. Here the Jenga analogy breaks down because, unlike the game, we won’t be able to rebuild the structure and start over.
This is not a message that political leaders, policymakers, or friends and neighbors want to hear. It is the inappropriate absolute truth. However, pulling civilization from collapse would be the most precious gift to the current generation to our descendants, the biosphere and the incredibly beautiful web of life.
William S. baker He is the former central regional director of the US Department of Energy who managed energy efficiency programs and renewable energy technologies, and also served as a special assistant to the Department’s Assistant Secretary for Energy Efficiency and Renewable Energy. Baker is also the executive director of the Presidential Climate Action Project, a nonpartisan initiative founded in 2007 that works with national thought leaders to develop recommendations for the White House as well as House and Senate committees on climate and energy policies. The project is not affiliated with the White House. | https://sdquarter.com/climate-change-the-global-jenga-game/ |
The maximum range of a projectile is directly proportional to the square of its velocity. A baseball pitcher throws a ball at 60 mi/h, with a maximum range of 242 ft. What is his maximum range if he throws the ball at 70 mi/h?
Experts are waiting 24/7 to provide step-by-step solutions in as fast as 30 minutes!*
Q: (use implicil dif- find ond dz 3 3 え+とナZ 3 3 ii) zz + zlny - z = z in) 1)
A: Click to see the answer
Q: Explain how to find the partial fraction decomposition of a rational expression with a prime quadrat...
A: Click to see the answer
Q: sketch the region bounded the followng by cuoves and find Othe Volume generated by Jevolving ° about...
A: The volume formed by revolution is given by the following figure The volume generated by revolving ...
Q: please solve the following integral
A: Click to see the answer
Q: solve the following differential equation
A: Click to see the answer
Q: Calculus Question
A: Equation of the curve is Formula to find surface area
Q: Solve formula for the specified variable.IR + Ir = E for I
A: Click to see the answer
Q: Solve the inequality
A: Here, 5q2+30q≤ -125 Add 125 to both sides 5q2+30q+125≤ -125+125 5q2+30q+125≤ 0
Q: find the area between the curves
A: The area between any two given curves f(x) and g(x), which intersect at two points having x-coordina... | https://www.bartleby.com/questions-and-answers/the-maximum-range-of-a-projectile-is-directly-proportional-to-the-square-of-its-velocity.-a-baseball/2e0a839f-bf32-4b57-b823-6f060476d896 |
so if you have $100 available on one credit card, and “almost” $200 in the bank, and you get paid in ten days, and your car is going to cost you $500 to fix (you would’ve had another $100 on another credit card, but you are stubborn and want to be able to get around on your own, so you rented a car . . . dumb decision, probably, but you got the cheapest car you could find, and for the shortest period of time possible . . . plus that extra $100 wouldn’t have helped anyway)
anyway . . . is there anybody out there who is really, REALLY good at math and can show me a solution to this word problem?
and iff you’re bad at math but good at praying, please send up a prayer for me to the God for whom no problem is too big, even when it feels that way from my wallet’s perspective . . . | https://littlemisstottenville.com/2007/06/20/a-puzzling-math-problem/?replytocom=50 |
BACKGROUND
SUMMARY
DETAILED DESCRIPTION
The present embodiments relate to integrated circuits and, more particularly, to performing double-precision floating-point multiplication operations using specialized processing blocks in an integrated circuit.
As applications increase in complexity, it has become more common to include specialized processing blocks in integrated circuits. Such specialized processing blocks may be partly or fully hardwired to perform one or more specific tasks, such as a logical or a mathematical operation. A specialized processing block may also contain one or more specialized structures, such as an array of configurable memory elements.
Examples of structures that are commonly implemented in such specialized processing blocks include: multipliers, arithmetic logic units (ALUs), barrel-shifters, various memory elements or storage circuits such as first-in first-out (FIFO) circuits, last-in first-out (LIFO) circuits, serial-in parallel-out (SIPO) shift register circuits, parallel-in serial-out (PISO) shift register circuits, random-access memory (RAM) circuits, read-only memory (ROM) circuits, content-addressable memory (CAM) circuits and register files, logic AND, logic NAND, logic OR, logic NOR arrays, etc., or combinations thereof.
One particularly useful type of specialized processing block, which is sometimes also referred to as a digital signal processing (DSP) block, may be used to process digital signals such as video signals, audio signals, etc. Such blocks are frequently also referred to as multiply-accumulate (MAC) blocks, because they include structures to perform multiplication operations, and sums and/or accumulations of multiplication operations.
Integrated circuits such as programmable integrated circuits sold by Altera Corporation, of San Jose, Calif., as part of the STRATIX® and ARRIA® families include specialized processing blocks, each of which includes a plurality of multipliers. Each of those specialized processing blocks also includes adders and registers, as well as programmable connectors (e.g., multiplexers) that allow the various components of the block to be configured in different ways.
Typically, the arithmetic operators (adders and multipliers) in such specialized processing blocks have been fixed-point operators. If floating-point operators were needed, they would be construct outside the specialized processing block using general-purpose programmable logic of the device, or using a combination of the fixed-point operators inside the specialized processing block with additional logic in the general-purpose programmable logic.
Double-precision floating-point multiplication circuitry that performs a double-precision floating-point multiplication of first and second double-precision floating-point numbers may include first and second specialized processing blocks. The first specialized processing block may generate a first bit and a first partial result of the double-precision floating-point multiplication. The second specialized processing block may include a first arithmetic operator circuit that computes a product of a first portion of the first double-precision floating-point number and a second portion of the second double-precision floating-point number, a second arithmetic operator circuit that computes a sum of the product and the first partial result, and an inter-block signaling circuit that generates a second bit and a second partial result based on the sum, and a third bit based on the sum and the first bit.
In certain embodiments, the above mentioned inter-block signaling circuit may include a logical OR gate that performs a logical OR operation of a subset of bits from the sum to generate a fourth bit.
If desired, the inter-block signaling circuit may further include an additional logical OR gate that performs a logical OR operation of the first and fourth bits to generate a fifth bit and a multiplexer that selects the third bit among the first bit, the fourth bit, and the fifth bit.
It is appreciated that the embodiments described herein can be implemented in numerous ways, such as a process, an apparatus, a system, a device, or a method executed on a processing machine. Several inventive embodiments are described below.
In certain embodiments, the above mentioned double-precision floating-point multiplication circuitry may further include a third specialized processing block that is configurable to select between performing a fixed-point operation, a single-precision floating-point operation, and a double-precision floating-point operation.
If desired, the third specialized processing block may include a third arithmetic operator circuit that computes an additional product of the first portion of the first double-precision floating-point number and a third portion of the second double-precision floating-point number.
In some embodiments, the above mentioned third specialized processing block may further include a fourth arithmetic operator circuit that receives the second bit, the second partial result, and the third bit from the second specialized processing block and the additional product from the third arithmetic operator circuit, simultaneously computes a plurality of results, and selects a result among the plurality of results based on the second bit and the third bit.
Further features of the invention, its nature and various advantages, will be apparent from the accompanying drawings and the following detailed description of the preferred embodiments.
The present embodiments provided herein relate to integrated circuits and, more particularly, to performing double-precision floating-point multiplication operations using specialized processing blocks in an integrated circuit.
Specialized processing blocks that perform arithmetic operations may be used in digital signal processing (DSP) applications (e.g., to process video signals, audio signals, etc.). Such specialized processing blocks often include a plurality of multipliers, adders, registers, and programmable connectors (e.g., multiplexers) that allow the various components of the specialized processing block to be configured in different ways.
Typically, the arithmetic operators (adders and multipliers) in such specialized processing blocks have been fixed-point operators. If floating-point operators were needed, they would be construct outside the specialized processing block (e.g., using additional logic in the integrated circuit, or using a combination of the fixed-point operators inside the specialized processing block with additional logic in the integrated circuit).
However, as applications increase in complexity, the use of floating-point operators, and in particular the use of double-precision floating-point operators, has become more common. Consequently, it is desirable to provide a specialized processing that is adaptable to efficiently implement fixed-point operations, single-precision floating-point operations, and double-precision floating-point operations.
It will be recognized by one skilled in the art, that the present exemplary embodiments may be practiced without some or all of these specific details. In other instances, well-known operations have not been described in detail in order not to unnecessarily obscure the present embodiments.
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An illustrative embodiment of a specialized processing block that is adaptable to efficiently implement fixed-point operations and floating-point operations is shown in .
In this logical representation, implementation details, such as registers and some programmable routing features, such as multiplexers that may allow the output of a particular structure to be routed around certain components or directly out of the specialized processing block, are omitted to simplify discussion.
FIG. 1
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In the logical representation of , “left multiplier” is a partial product generator such as an 18×18 partial product generator, which may be used, e.g., as two 9×18 partial product generators, if desired. Left multiplier may produce two dimensionless output vectors , . Similarly, “right multiplier” is a partial product generator such as an 18×18 partial product generator, which may be used, e.g., as a 18×9 partial product generator and a 27×9 partial product generator. Right multiplier may produce two dimensionless output vectors , .
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Together, left multiplier and right multiplier may implement a 27×27 partial product generator to support single-precision floating-point multiplication, which under the IEEE 754-1985 standard has a mantissa size of 23 bits (exclusive of an implied leading ‘1’). Input multiplexer stage may combine and align between four and six inputs according to the needs of a particular user logic design.
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Multiplexers , may align vectors , , , and , respectively, according to the type of operation being performed, as determined by a user design, if desired. Specifically, vectors , , , and may be totally offset from one another (e.g., to perform two separate smaller multiplications, such as two 9×9 multiplications), totally aligned with one another (e.g., to perform one larger multiplication, such as one 18×18 multiplication), or partially aligned with one another (e.g., to perform a “rectangular” multiplication, such as a 9×18 multiplication).
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4:2 compressor may combine the four dimensionless output vectors , , , and into two dimensionless output vectors and . If desired, each of the input and output vectors of 4:2 compressor may be up to 74 bits wide.
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Specialized processing block may receive another vector from another specialized processing block. 3:2 compressor may receive vector , along with vectors and and provide vectors and . Multiplexer may select between vectors , and vectors , , allowing 3:2 compressor to be bypassed if cascade input is not used. AND gate may set input to zero when, for example, the structure is being used in an accumulator mode and the accumulator has to be reset.
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Output vectors and may each be up to 74 bits wide and are input to main adder to provide the resultant product of the multiplication operation, which can be a fixed-point output or a floating-point output . In a floating-point case, the exponent may be handled at .
When multiplying two floating-point numbers according to the IEEE 754-1985 standard, the input multiplicands are normalized numbers between decimal 1.0 and decimal 1.999 . . . . Therefore, the resultant product can be between decimal 1.0 and decimal 3.999 . . . , and may be subject to normalization and rounding.
To accommodate normalization and rounding, it may be necessary to add either zero, one or two to the least significant bit(s) of the result (which may be referred to as the sum).
Specifically, normalization may involve a right shift of zero bits or one bit (if the result is greater than or equal to decimal 1.0 and less than decimal 2.0, the right shift is zero bits; if the result is greater than or equal to decimal 2.0 and less than decimal 4.0 the right shift is one bit). In cases where rounding is not applied, whether the normalization is O bit or 1 bit, the sum-plus-zero (i.e., the sum) may be used. In cases where rounding is applied, then if the normalization is zero bits, the sum-plus-1 may be used, while if the normalization is one bit, the sum-plus-2 may be used.
Therefore, in accordance with embodiments, and as described in more detail below, those three quantities (sum, sum-plus-1 and sum-plus-2) are generated simultaneously using different portions of the circuitry, and then one of the three quantities is selected as the final result using a signal (e.g., a carry signal) from another portion of the calculation, thereby eliminating the need to wait for the other portion of the calculation before generating the appropriate result (i.e., sum, sum-plus-1 or sum-plus-2).
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In one embodiment, generating the three results simultaneously is accomplished by decomposing adder into two adders (e.g., low adder and a middle adder of ), which may be used together to perform a single fixed-point addition (e.g., adding two 74-bit numbers), a single-precision floating-point multiplication, or a double-precision floating-point multiplication.
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If desired, a plurality of specialized processing blocks may implement together a double-precision floating-point multiplication of first and second double-precision floating-point numbers. As an example, shows four specialized processing blocks , , , and that are arranged in a cascade chain and perform a double-precision floating-point multiplication of double-precision floating-point numbers A and B.
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In some embodiments, one or more specialized processing blocks of specialized processing blocks , , , and may be identical. For example, specialized processing block of may implement specialized processing blocks , , , and . In this example, four identical specialized processing blocks may each be configured differently such that the configured specialized processing blocks implement the respective functionality of specialized processing blocks , , , and of .
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If desired, specialized processing blocks , , , and may be arranged in a row or a column. If desired, a row or a column may include more than four specialized processing blocks. In the example in which four identical specialized processing blocks are configured differently to implement the functionality of specialized processing blocks , , , and , any subset of four neighboring specialized processing blocks in a row or a column may implement a double-precision floating-point multiplication. If desired, an integrated circuit may include one or more rows or columns of specialized processing blocks.
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Double-precision floating-point numbers A and B may have 54-bit mantissas, and each specialized processing block , , , and may receive a respective portion of double-precision floating-point numbers A and B. For example, specialized processing block may receive the 27 least significant bits (LSBs) of A and B (i.e., A[27:1] and B[27:1]), specialized processing block may receive the 27 least significant bits (LSBs) of A and the 27 most significant bits (MSBs) of B (i.e., A[27:1] and B[54:28]), specialized processing block may receive the 27 most significant bits (MSBs) of A and the 27 least significant bits (LSBs) of B (i.e., A[54:28] and B[27:1]), and specialized processing block may receive the 27 most significant bits (MSBs) of A and B (i.e., A[54:28] and B[54:28]).
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If desired, specialized processing block , , , and may each include a first arithmetic operator circuit , , , and and a second arithmetic operator circuit , , , and . Specialized processing blocks , , and may include inter-block signaling circuits , , and . If desired, specialized processing block may also include an inter-block signaling circuit (not shown).
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The first arithmetic operator circuit of each specialized processing block may generate a partial product of the respective portions of the first and second double-precision floating-point numbers. For example, multiplier may generate the partial product of the 27 least significant bits (LSBs) of A and B (i.e., A[27:1] and B[27:1]), multiplier may generate the partial product of the 27 least significant bits (LSBs) of A and the 27 most significant bits (MSBs) of B (i.e., A[27:1] and B[54:28]), multiplier may generate the partial product of the 27 most significant bits (MSBs) of A and the 27 least significant bits (LSBs) of B (i.e., A[54:28] and B[27:1]), and multiplier may generate the partial product of the 27 most significant bits (MSBs) of A and B (i.e., A[54:28] and B[54:28]).
The second arithmetic operator circuit of each specialized processing block may generate a combined partial product by combining the partial product from the first arithmetic operator circuit with another combined partial product from a neighboring specialized processing block of the plurality of specialized processing blocks that is arranged upstream in the cascade chain.
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For example, second arithmetic operator circuit of specialized processing block may generate a combined partial product by combining the partial product from first arithmetic operator circuit and the combined partial product from specialized processing block . Similarly, second arithmetic operator circuit of specialized processing block may generate a combined partial product by combining the partial product from first arithmetic operator circuit and the combined partial product from specialized processing block ; and second arithmetic operator circuit of specialized processing block may generate a combined partial product by combining the partial product from first arithmetic operator circuit and the combined partial product from specialized processing block .
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Each specialized processing block may output ranges of the combined partial product as a range of the double-precision floating-point multiplication result C. For example, specialized processing block may output the 27 LSBs (i.e., C[27:1]) of the double-precision floating-point multiplication result. Similarly, specialized processing blocks and may output the next 27 bits (i.e., C[54:28]) and the 54 MSBs (i.e., C[108:55]) of the double-precision floating-point multiplication result, respectively.
The inter-block signaling circuit may select a portion of the respective combined partial product generated by the respective second arithmetic operator circuit for the neighboring specialized processing block of the plurality of specialized processing block that is arranged downstream in the cascade chain.
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For example, inter-block signaling circuit of specialized processing block may select the 29 MSB (i.e., bits [56:28]) of the combined partial product generated by second arithmetic operator circuit and send the selected bits to specialized processing block . Similarly, inter-block signaling circuit of specialized processing block may select all 56 bits (i.e., bits [56:1]) of the combined partial product generated by second arithmetic operator circuit and send the selected bits to specialized processing block ; and inter-block signaling circuit of specialized processing block may select all 56 bits (i.e., bits [56:1]) of the combined partial product generated by second arithmetic operator circuit and send the selected bits to specialized processing block .
If desired, the inter-block signaling circuit of each specialized processing block may generate a sticky bit and a round bit for the neighboring specialized processing block of the plurality of specialized processing blocks that is arranged downstream in the cascade chain.
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For example, inter-block signaling circuit of specialized processing block may generate a sticky bit and a round bit for specialized processing block , inter-block signaling circuit of specialized processing block may generate a sticky bit and a round bit for specialized processing block , and inter-block signaling circuit of specialized processing block may generate a sticky bit and a round bit for specialized processing block .
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is a diagram of an illustrative specialized processing block with first and second arithmetic circuits and and inter-block signaling circuit in accordance with an embodiment. As shown, specialized processing circuit may receive respective portions of first and second double-precision floating-point numbers, sticky bit and cascade-in signal from neighboring specialized processing block and provide sticky bit , round bit , and cascade-out signal to neighboring specialized processing block .
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If desired, first arithmetic operator circuit and second arithmetic operator circuit may be configured to implement a multiplication and an addition operation, respectively. In this configuration, first arithmetic operator circuit may compute a product of the respective portions of the first and second double-precision floating-point numbers and provide the product to second arithmetic operator circuit . Second arithmetic operator circuit may compute a sum of the product and cascade-in signal , and provide the sum to inter-block signaling circuit .
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As shown, inter-block signaling circuit may include logical OR gates and , multiplexers and , logical AND gate , and right shifter .
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Right shifter may receive the sum signal and shift the sum signal a predetermined number of bits to the right. For example, right shifter may receive a sum signal that includes 56 bits and shift the sum signal 27 bits to the right, thereby generating a right shifted sum signal that has 27 bits of zero followed by the 29 MSBs of the sum signal as the 29 LSBs of the right shifted sum signal.
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Multiplexer may receive the sum signal and the right shifted sum signal and generate cascade out signal by selecting between the sum signal and the right shifted sum signal. If desired, the selection may be based on the position of specialized processing block within a cascade chain of specialized processing blocks that perform a double-precision floating-point multiplication operation (e.g., whether specialized processing block implements specialized processing block , , or of ). For example, specialized processing block may generate cascade out signal by selecting the right shifted sum signal, and specialized processing blocks and may both generate cascade out signal by selecting the sum signal.
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Logical OR gate may receive a portion of the sum signal and generate a first additional sticky bit by performing a logical OR function of a predetermined number of LSBs of the sum signal. For example, logical OR gate may receive the 27 LSBs of the sum signal and perform a logical OR function of the 27 LSBs of the sum signal to generate the first additional sticky bit.
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Logical OR gate may generate a second additional sticky bit by performing a logical OR function of sticky bit and the first additional sticky bit from logical OR gate .
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Multiplexer may receive sticky bit and first and second additional sticky bits and generate sticky bit by selecting between sticky bit and first and second additional sticky bits. If desired, the selection may be based on the position of specialized processing block within a cascade chain of specialized processing blocks that perform a double-precision floating-point multiplication operation (e.g., whether specialized processing block implements specialized processing block , , or of ). For example, specialized processing block of may output the first additional sticky bit, specialized processing block may output sticky bit from specialized processing block , and specialized processing block may output the second additional sticky bit.
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Inter-block signaling circuit may generate round bit by providing one bit of the sum signal through logical AND gate to neighboring specialized processing block . Logical AND gate may selectively set round bit to zero based on the position of specialized processing block within a cascade chain of specialized processing blocks that perform a double-precision floating-point multiplication operation (e.g., whether specialized processing block implements specialized processing block , , , or of ). For example, logical AND gate may set round bit to zero if inter-block signaling circuit is in specialized processing blocks , , and of . Logical AND gate may output one bit of the sum signal in specialized processing block .
As shown above, to accommodate normalization and rounding, it may be necessary to add either zero, one, or decimal two to the least significant bit(s) of the result. Specifically, in cases where rounding is not applied, whether the normalization is zero bits or one bit, a sum-plus-zero signal (i.e., the sum signal) may be used. In cases where rounding is applied, then if the normalization is zero bits, a sum-plus-1 signal (i.e., a one added to the sum signal) may be used, while if the normalization is one bit, a sum-plus-2 signal (i.e., a decimal two added to the sum signal) may be used.
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If desired, different portions of a specialized processing block such as specialized processing block may generate those three signals (i.e., sum signal, sum-plus-1 signal, and sum-plus-2 signal) simultaneously, and then select between these three signals using a control signal from another portion of the specialized processing block, thereby parallelizing portions of the double-precision floating-point multiplication operation.
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An embodiment of circuitry that simultaneously computes the sum signal, the sum-plus-one signal, and the sum-plus-two signal and then selects between these three signals to determine the result of a single-precision floating-point operation or a double-precision floating-point operation is shown in . If desired, the circuitry of may replace adder of .
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As shown, the circuitry of includes low adder , middle adder , prefix network , logical OR gate , float round circuit , and multiplexers , , , , , and , and may implement a fixed-point operation (e.g., a single fixed-point addition operation or two separate fixed-point addition operations), a single-precision floating-point operation (e.g., rounding for a single-precision floating-point multiplication operation), or a double-precision floating-point operation (e.g., a double-precision floating-point multiplication operation).
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Low adder and/or middle adder may receive portions of partial products computed by additional circuitry (e.g., 4:2 compressor of ). As an example, middle adder may receive the partial products when performing in single-precision floating-point multiplication operation, generate the sum-plus-zero signal, the sum-plus-one signal, and the sum-plus-two signal of the single-precision floating-point multiplication result, and provide these three signals to multiplexer .
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As another example, low adder and middle adder may receive the LSBs and the MSBs of partial products of a double-precision floating-point multiplication operation, respectively. Low adder may generate the sum-plus-zero signal, the sum-plus-one signal, and the sum-plus-two signal for the LSBs of the double-precision floating-point multiplication result, and provide these three signals to multiplexer .
420
430
430
420
410
464
Middle adder may compute the sum of the MSBs of the partial products and provide the sum to prefix network . Prefix network may then generate the sum-plus-zero signal, the sum-plus-one signal, and the sum-plus-two signal for the MSBs of the double-precision floating-point multiplication result based on the sum signal from middle adder and the MSB of the sum signal from low adder , and provide these three signals to multiplexer .
456
460
462
464
450
452
454
Float round circuit may generate a control signal that selects between the respective sum-plus-zero signal, sum-plus-one signal, and sum-plus-two signal at multiplexers , , and based on signals received from multiplexers , , and .
440
410
410
410
Logical OR gate may generate a round-to-nearest-even signal by performing a logical OR function of the 23 LSBs of the sum-plus-zero signal from low adder to determine the presence of a one in any bit location, signifying, when the highest bit from low adder is a one, whether the result from low adder is exactly decimal 0.5 or greater than decimal 0.5.
454
397
410
452
420
410
450
390
440
FIG. 3
FIG. 3
As shown, multiplexer may receive a float round bit (e.g., round bit of from a neighboring specialized processing block) and the carry bit from low adder , multiplexer may receive the lowermost bits from middle adder and the lowermost bits from low adder , and multiplexer may receive a sticky bit (e.g., sticky bit of from a neighboring specialized processing block) and the round-to-nearest-even signal from logical OR gate .
FIG. 4
FIG. 4
454
410
452
420
450
440
454
452
410
450
When the circuitry of is configured to implement a single-precision floating-point rounding operation, multiplexer may select the carry bit from low adder , multiplexer the lowermost bits from middle adder , and multiplexer the round-to-nearest-even signal from logical OR gate , whereas when the circuitry of is configured to implement a double-precision floating-point rounding operation, multiplexer may select the float round bit, multiplexer the lowermost bits of the sum-plus-zero signal from low adder , and multiplexer the sticky bit.
505
510
505
501
502
104
FIG. 5
FIG. 1
An embodiment of a circuit that may implement a portion of the circuitry that generates sum-plus-zero, sum-plus-one, and sum-plus-two signals is shown in . As shown, half adders of circuit may receive signals and , which may include 31-bit portions of partial products of a floating-point multiplication operation (e.g., the partial products computed by 4:2 compressor of or the MSBs of partial products of a double-precision floating-point multiplication operation).
505
505
510
505
510
505
Circuit may perform fixed-point, single-precision floating-point, and double-precision floating-point operations and support up to 31 bits of precision. In some embodiments, circuit may exclusively perform single-precision and/or double-precision floating-point operations and support fewer bits of precision. For example, half adders may include 23 half adders instead of the shown 32 half adders if circuit performs exclusively single-precision floating-point operations. If desired, half adders may include 27 half adders instead of the shown 32 half adders if circuit performs single-precision and double-precision floating-point operations.
510
513
523
513
501
502
523
501
502
523
410
FIG. 4
As shown, half adder may generate two 32-bit signals, which may be referred to as half-add-sum and half-add-carry . Half-add-sum may be the 31-bit result of the bitwise logical XOR operation of signals and ; the 32nd bit is not used. Half-add-carry may be a 32-bit signal resulting from a 1-bit left-shift of the bitwise logical AND operation of signals and . In single-precision floating-point operation mode, a zero may be inserted in the least-significant bit position of half-add-carry , whereas the most-significant bit from low adder of may be inserted in double-precision floating-point operation mode, if desired.
513
523
533
543
553
563
510
533
543
553
563
520
530
540
520
530
540
520
530
540
In some embodiments, signals and may be divided into lower 14 bits (i.e., signals and ) and upper 17 bits (i.e., signals and ), respectively. Half adder may provide signals , , , and to a first parallel prefix network tree, which may include prefix networks , , and . Each prefix network of prefix networks , , and may be, for example, a Kogge-Stone prefix network or any other prefix network such as a Brent-Kung prefix network or a Han Carlson prefix network, just to name a few. Each prefix network of prefix networks , , and may output respective generate and propagate vectors.
520
533
543
515
525
530
553
563
535
545
540
540
503
520
For example, prefix network may receive signals and and provide 14-bit generate signal and 14-bit propagate signal , and prefix network may receive signals and and provide 17-bit generate signal and 17-bit propagate signal to prefix network . Prefix network may also receive the prefix (g, p) output of the highest node of prefix network .
540
555
565
515
525
575
585
Prefix network may provide generate signal and propagate signal , which may be concatenated with generate signal and propagate signal , respectively, to provide 31-bit single-precision generate signal and 31-bit single-precision propagate signal .
550
575
585
550
550
507
410
FIG. 4
A second parallel prefix network tree, which may include prefix network , may receive the 31-bit generate signal and the 31-bit propagate signal . If desired, prefix network may receive additional signals. For example, prefix network may receive the prefix (g, p) output of low adder of (i.e., signals g_low[23:22] and p_low[23:22]).
550
550
576
586
507
575
585
Prefix network may be, for example, a Kogge-Stone prefix network or any other prefix network such as a Brent-Kung prefix network or a Han Carlson prefix network, just to name a few. Prefix network may generate 31-bit double-precision generate signal and 31-bit double-precision propagate signal by incorporating the prefix (g, p) output with the single-precision generate and propagate signals and , using for each of the 31 bits a single logical AND gate and a single logical OR gate, respectively, if desired.
560
576
586
575
585
Multiplexer may receive the double-precision generate and propagate signals and , the single-precision generate and propagate signals and , and a control signal (e.g., signal FLOAT). If desired, the control signal may indicate whether the specialized processing block is configured to perform a single-precision floating-point operation (e.g., signal FLOAT is equal to ‘1’) or a double-precision floating-point operation (e.g., signal FLOAT is equal to ‘0’).
560
575
585
562
564
560
576
586
562
564
For example, in response to indicating that the specialized processing block is configured to perform a single-precision floating-point operation, multiplexer may select single-precision generate and propagate signals and as 31-bit generate and propagate signals and (i.e., signals g_x[31:1] and p_x[31:1]), respectively. In response to indicating that the specialized processing block is configured to perform a double-precision floating-point operation, multiplexer may select double-precision generate and propagate signals and as 31-bit generate and propagate signals and (i.e., signals g_x[31:1] and p_x[31:1]), respectively.
580
513
523
516
If desired, logical exclusive OR gate , which is sometimes also referred to as logical XOR gate, XOR gate or XOR, may perform a logical XOR operation of half-add-sum signal and half-add-carry signal to provide signal (i.e., signal aa_bb[31:1]).
570
513
508
410
FIG. 4
Multiplexer may receive the LSB of half-add-sum signal , the LSB of a corresponding signal from low adder of (i.e., signal aah_low[1]), and a control signal (e.g., signal FLOAT). If desired, the control signal may indicate whether the specialized processing block is configured to perform a single-precision floating-point operation (e.g., signal FLOAT is equal to ‘1’) or a double-precision floating-point operation (e.g., signal FLOAT is equal to ‘0’).
570
572
570
508
572
For example, in response to indicating that the specialized processing block is configured to perform a single-precision floating-point operation, multiplexer may select the LSB of half-add-sum as output signal (i.e., aah_x). In response to indicating that the specialized processing block is configured to perform a double-precision floating-point operation, multiplexer may select signal (i.e., aah_low[1]) as output signal .
505
516
562
564
572
Circuit may provide signals , , , and to additional circuitry that generates sum-plus-zero, sum-plus-one, and sum-plus-two signals. Such circuitry may perform fixed-point, single-precision floating-point, and double-precision floating-point operations and therefore are computed to 31 bits of precision. However, in some embodiments the sum-plus-two and sum-plus-one signals may only be used for floating-point operations. In such an embodiment sum-plus-one and sum-plus-two signals may only be 29 bits wide.
505
682
683
689
685
686
687
688
693
690
691
692
694
FIG. 6
An embodiment of the circuitry that generates the sum-plus-one signal based on the signals generated by circuit is shown in . As shown, the circuitry may include logical AND gates , , and , logical OR gates , and , multiplexers and , logical exclusive OR gates , , and , and inverter .
689
572
564
687
689
562
690
687
516
Logical AND gate may perform the logical AND operation of signal (i.e., aah_x) and the 29 LSBs of signal (i.e., p_x[29:1]), logical OR gate may perform the logical OR operation of the output of logical AND gate and the 29 LSBs of signal (i.e., g_x[29:1]), and logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and the 29 MSBs of signal (i.e., aa_bb[31:3]) to generate the 29 MSBs of the sum-plus-one signal (i.e., sum-plus-one[31:3]).
683
572
23
507
686
683
23
507
688
686
572
691
688
2
516
2
Logical AND gate may perform the logical AND operation of signal (i.e., aah_x) and bit of the propagate portion of signal (i.e., p_low[23]), and logical OR gate may perform the logical OR operation of the output of logical AND gate and bit of the generate portion of signal (i.e., g_low[23]). Multiplexer may select the output of logical OR gate when the specialized processing block performs a double-precision floating-point operation and signal (i.e., aah_x) when the specialized processing block performs a single-precision floating-point operation. Logical exclusive OR gate may perform the logical XOR operation of the output of multiplexer and bit of signal (i.e., aa_bb[2]) to generate bit of the sum-plus-one signal (i.e., sum-plus-one[2]).
682
572
22
507
685
682
22
507
692
685
1
516
694
572
693
692
572
1
Logical AND gate may perform the logical AND operation of signal (i.e., aah_x) and bit of the propagate portion of signal (i.e., p_low[22]), and logical OR gate may perform the logical OR operation of the output of logical AND gate and bit of the generate portion of signal (i.e., g_low[22]). Logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and bit of signal (i.e., aa_bb[1]). Inverter may invert signal (i.e., aah_x), and multiplexer may select the output of logical XOR gate when the specialized processing block performs a double-precision floating-point operation and inverted signal (i.e., NOT(aah_x)) when the specialized processing block performs a single-precision floating-point operation to generate bit of the sum-plus-one signal (i.e., sum-plus-one[1]).
505
785
786
787
788
793
790
791
792
794
FIG. 7
An embodiment of the circuitry that generates sum-plus-two based on the signals generated by circuit is shown in . As shown, the circuitry may include logical OR gates , , and , multiplexers and , and logical exclusive OR gates , , , and .
787
562
564
790
787
516
Logical OR gate may perform the logical OR operation of the 29 LSBs of signals and (i.e., g_x[29:1] and p_x[29:1]), and logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and the 29 MSBs of signal (i.e., aa_bb[31:3]) to generate the 29 MSBs of the sum-plus-two signal (i.e., sum-plus-two[31:3]).
786
23
507
788
786
791
788
2
516
794
791
Logical OR gate may perform the logical OR operation of bit of the generate and propagate portions of signal (i.e., g_low[23] and p_low[23]). Multiplexer may select the output of logical OR gate when the specialized processing block performs a double-precision floating-point operation and a constant zero when the specialized processing block performs a single-precision floating-point operation. Logical exclusive OR gate may perform the logical XOR operation of the output of multiplexer and bit of signal (i.e., aa_bb[2]). Logical exclusive OR gate may perform the logical XOR operation of the output of logical exclusive OR gate and a control signal (e.g., signal FLOAT).
794
791
2
791
2
Consider the scenario in which the control signal indicates whether the specialized processing block is configured to perform a single-precision floating-point operation (i.e., signal FLOAT is equal to ‘1’) or a double-precision floating-point operation (i.e., signal FLOAT is equal to ‘0’). In this scenario, the logical exclusive OR gate may invert the output of logical exclusive OR gate to generate bit of the sum-plus-two signal (i.e., sum-plus-two[2]) when the specialized processing block is configured to perform a single-precision floating-point operation and provide the output of logical exclusive OR gate as bit of the sum-plus-two signal (i.e., sum-plus-two[2]) when the specialized processing block is configured to perform a double-precision floating-point operation.
785
22
507
792
785
1
516
793
792
572
1
Logical OR gate may perform the logical OR operation of bit of the generate and propagate portions of signal (i.e., g_low[22] and p_low[22]). Logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and bit of signal (i.e., aa_bb[1]). Multiplexer may select the output of logical exclusive OR gate when the specialized processing block performs a double-precision floating-point operation and signal (i.e., aah_x) when the specialized processing block performs a single-precision floating-point operation to generate bit of the sum-plus-two signal (i.e., sum-plus-two[1]).
505
850
860
870
880
890
FIG. 8
An embodiment of the circuitry that generates sum-plus-zero based on the signals generated by circuit is shown in . As shown, the circuitry may include multiplexers and and logical exclusive OR gates , , and .
890
562
516
Logical exclusive OR gate may perform the logical XOR operation of the 29 LSBs of signal (i.e., g_x[29:1]) and the 29 MSBs of signal (i.e., aa_bb[31:3]) to generate the 29 MSBs of the sum-plus-zero signal (i.e., sum-plus-zero[31:3]).
880
23
507
2
516
860
880
2
516
2
Logical exclusive OR gate may perform the logical XOR operation of bit of the generate portion of signal (i.e., g_low[23]) and bit of signal (i.e., aa_bb[2]). Multiplexer may select the output of logical exclusive OR gate when the specialized processing block performs a double-precision floating-point operation and bit of signal (i.e., aa_bb[2]) when the specialized processing block performs a single-precision floating-point operation to generate bit of the sum-plus-zero signal (i.e., sum-plus-zero[2]).
870
22
507
1
516
850
870
572
1
Logical exclusive OR gate may perform the logical XOR operation of bit of the generate portion of signal (i.e., g_low[22]) and bit of signal (i.e., aa_bb[1]). Multiplexer may select the output of logical exclusive OR gate when the specialized processing block performs a double-precision floating-point operation and signal (i.e., aah_x) when the specialized processing block performs a single-precision floating-point operation to generate bit of the sum-plus-zero signal (i.e., sum-plus-zero[1]).
FIG. 6
FIG. 7
FIG. 8
FIG. 9
900
900
926
910
912
914
940
942
944
920
922
924
930
932
934
962
964
969
950
952
954
956
958
960
970
972
If desired, the circuitry that generates the sum-plus-one signal of , the sum-plus-two signal of , and the sum-plus-zero signal of may be combined into a single circuit. An embodiment of such a circuit is shown as circuit in . As shown, circuit may include inverter , logical OR gates , , , , , and , logical AND gates , , , , , , , , and , logical exclusive OR gates , , , , and , and multiplexers , , and .
505
516
562
564
572
900
507
900
900
900
FIG. 5
In addition to the signals generated by circuit of (i.e., signals , , , and ), circuit may receive signals , “FLOAT”, “+0”, “+1”, and “+2”. If desired, signal “FLOAT” may indicate whether circuit performs a single-precision floating-point or a double-precision floating-point operation. For example, signal “FLOAT” may be one if circuit is configured to perform a single-precision floating-point operation and zero if circuit is configured to perform a double-precision floating-point operation.
900
900
900
900
900
Signals “+0”, “+1”, and “+2” may indicate whether circuit generates the sum-plus-zero signal, the sum-plus-one signal, or the sum-plus-two signal, respectively. For example, signals “+0”, “+1”, and “+2” may be one if circuit generates the sum-plus-zero signal, the sum-plus-one signal, and the sum-plus-two signal, respectively, and zero otherwise. In other words, signal “+0” may be one and signals “+1” and “+2” zero if circuit generates the sum-plus-zero signal. Similarly, signal “+1” may be one and signals “+0” and “+2” zero if circuit generates the sum-plus-one signal, and signal “+2” may be one and signals “+0” and “+1” zero if circuit generates the sum-plus-two signal.
900
969
910
912
914
926
564
23
507
22
507
930
932
934
Consider the scenario in which circuit generates the sum-plus-two signal for a floating-point operation. In this scenario, signals “+0”, “+1”, and “+2” may be set to ‘0’, ‘0’, and ‘1’, respectively. Thus, the output of logical AND gate may be ‘0’, and the outputs of logical OR gates , , and and of inverter may be ‘1’, which may result in propagating the 29 LSBs of signal (i.e., p_x[29:1]), bit of the propagate portion of signal (i.e., p_low[23]), and bit of the propagate portion of signal (i.e., p_low[22]) from the respective inputs to outputs of logical AND gates , , and , respectively.
940
562
564
950
940
516
FIG. 7
Thus, logical OR gate may perform the logical OR operation of the 29 LSBs of signals and (i.e., g_x[29:1] and p_x[29:1]), and logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and the 29 MSBs of signal (i.e., aa_bb[31:3]) to generate the 29 MSBs of the result signal (i.e., result[31:3]), which is logically equivalent to the 29 MSBs of the sum-plus-two signal (i.e., sum-plus-two[31:3]) of .
942
23
507
960
942
969
Logical OR gate may perform the logical OR operation of bit of the generate and propagate portions of signal (i.e., g_low[23] and p_low[23]). Multiplexer may select the output of logical OR gate when the specialized processing block performs a double-precision floating-point operation and the output of logical AND gate (i.e., constant ‘0’) when the specialized processing block performs a single-precision floating-point operation.
952
960
2
516
956
952
962
962
2
952
952
2
FIG. 7
Logical exclusive OR gate may perform the logical XOR operation of the output of multiplexer and bit of signal (i.e., aa_bb[2]), and logical exclusive OR gate may perform the logical XOR operation of the output of logical exclusive OR gate and the output of logical AND gate . Logical AND gate may be one when performing a single-precision floating-point operation and zero when performing a double-precision floating-point operation. Thus, bit of the result signal (i.e., result[2]) may be the signal from logical exclusive OR gate when performing a double-precision floating-point operation and the inverse of the signal from logical exclusive OR gate when performing a single-precision floating-point operation, which is logically equivalent to bit of the sum-plus-two signal (i.e., sum-plus-two[2]) of .
944
22
507
954
944
1
516
972
954
958
572
1
1
FIG. 7
Logical OR gate may perform the logical OR operation of bit of the generate and propagate portions of signal (i.e., g_low[22] and p_low[22]). Logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and bit of signal (i.e., aa_bb[1]). Multiplexer may select the output of logical XOR gate when the specialized processing block performs a double-precision floating-point operation and the output of logical exclusive OR gate , which is signal (i.e., aah_x) since “+1” is ‘0’, when the specialized processing block performs a single-precision floating-point operation to generate bit of the result signal, which is logically equivalent to bit of the sum-plus-two signal (i.e., sum-plus-two[1]) of .
900
910
912
914
920
922
924
Consider the scenario in which circuit generates the sum-plus-one signal for a floating-point operation. In this scenario, signals “+0”, “+1”, and “+2” may be set to ‘0’, ‘1’, and ‘0’, respectively. Thus, logical OR gates , , and may propagate the respective other signal than “+2” to logical AND gates , , and , respectively.
920
572
564
940
920
926
562
950
940
516
FIG. 6
Thus, logical AND gate may perform the logical AND operation of signal (i.e., aah_x) and the 29 LSBs of signal (i.e., p_x[29:1]), logical OR gate may perform the logical OR operation of the output of logical AND gate (since the output of inverter is ‘1’) and the 29 LSBs of signal (i.e., g_x[29:1]), and logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and the 29 MSBs of signal (i.e., aa_bb[31:3]) to generate the 29 MSBs of the result signal (i.e., result[31:3]), which is logically equivalent to the sum-plus-one signal (i.e., sum-plus-one[31:3]) of .
922
572
23
507
942
922
23
507
960
942
969
572
952
960
2
516
956
952
962
2
FIG. 6
Logical AND gate may perform the logical AND operation of signal (i.e., aah_x) and bit of the propagate portion of signal (i.e., p_low[23]), and logical OR gate may perform the logical OR operation of the output of logical AND gate and bit of the generate portion of signal (i.e., g_low[23]). Multiplexer may select the output of logical OR gate when the specialized processing block performs a double-precision floating-point operation and the output of logical AND gate , which may be signal (i.e., aah_x) since “+1” is one, when the specialized processing block performs a single-precision floating-point operation. Logical exclusive OR gate may perform the logical XOR operation of the output of multiplexer and bit of signal (i.e., aa_bb[2]). Logical exclusive OR gate may propagate the output of logical exclusive OR gate (since “+2” is zero and thus the output of logical AND gate is zero) to generate bit of the result signal (i.e., result[2]), which is logically equivalent to the sum-plus-one signal (i.e., sum-plus-one[2]) of .
924
572
22
507
944
924
22
507
954
944
1
516
958
572
972
954
572
1
FIG. 6
Logical AND gate may perform the logical AND operation of signal (i.e., aah_x]) and bit of the propagate portion of signal (i.e., p_low[22]), and logical OR gate may perform the logical OR operation of the output of logical AND gate and bit of the generate portion of signal (i.e., g_low[22]). Logical exclusive OR gate may perform the logical XOR operation of the output of logical OR gate and bit of signal (i.e., aa_bb[1]). Logical exclusive OR gate may invert signal (i.e., aah_x) since signal “+1” is one, and multiplexer may select the output of logical XOR gate when the specialized processing block performs a double-precision floating-point operation and inverted signal (i.e., NOT(aah_x)) when the specialized processing block performs a single-precision floating-point operation to generate bit of the result signal (i.e., result[1]), which is logically equivalent to the sum-plus-one signal (i.e., sum-plus-one[1]) of .
900
926
930
932
934
562
23
507
22
507
940
942
944
Consider the scenario in which circuit generates the sum-plus-zero signal for a floating-point operation. In this scenario, signals “+0”, “+1”, and “+2” may be set to ‘1’, ‘0’, and ‘0’, respectively. Thus, the output of inverter may be ‘0’, which may result in the outputs of logical AND gates , , and being ‘0’, which in turn may result in propagating the 29 LSBs of signal (i.e., g_x[29:1]), bit of the generate portion of signal (i.e., g_low[23]), and bit of the generate portion of signal (i.e., g_low[22]) from the respective inputs to outputs of logical OR gates , , and , respectively.
950
940
516
FIG. 8
Logical exclusive OR gate may perform the logical XOR operation of the signal from logical OR gate (i.e., g_x[29:1]) and the 29 MSBs of signal (i.e., aa_bb[31:3]) to generate the 29 MSBs of the result signal (i.e., result[31:3]), which is logically equivalent to the sum-plus-zero signal (i.e., sum-plus-zero[31:3]) of .
952
23
507
2
516
960
942
952
960
2
516
956
952
962
970
970
952
2
516
2
FIG. 8
Logical exclusive OR gate may perform the logical XOR operation of bit of the generate portion of signal (i.e., g_low[23]) and bit of signal (i.e., aa_bb[2]). Multiplexer may select the output of logical OR gate when the specialized processing block performs a double-precision floating-point operation, and logical exclusive OR gate may perform the logical XOR operation of the output of multiplexer and bit of signal (i.e., aa_bb[2]). Logical exclusive OR gate may propagate the output of logical exclusive OR gate (since “+2” is zero and thus the output of logical AND gate is zero) to multiplexer . Multiplexer may select the output of logical exclusive OR gate when the specialized processing block performs a double-precision floating-point operation and bit of signal (i.e., aa_bb[2]) when the specialized processing block performs a single-precision floating-point operation to generate bit of the result signal (i.e., result[2]), which is logically equivalent to the sum-plus-zero signal (i.e., sum-plus-zero[2]) of .
954
944
22
507
1
516
972
954
572
1
FIG. 8
Logical exclusive OR gate may perform the logical XOR operation of the signal from logical OR gate (i.e., bit of the generate portion of signal (i.e., g_low[22])) and bit of signal (i.e., aa_bb[1]). Multiplexer may select the output of logical exclusive OR gate when the specialized processing block performs a double-precision floating-point operation and signal (i.e., aah_x) when the specialized processing block performs a single-precision floating-point operation to generate bit of the result signal (i.e., result[1]), which is logically equivalent to the sum-plus-zero signal (i.e., sum-plus-zero[1]) of .
FIG. 10
is a diagram of a flow chart showing illustrative steps for operating a specialized processing block in accordance with an embodiment.
1010
During operation , the specialized processing block may receive a first portion of a first double-precision floating-point number, a second portion of a second double-precision floating-point number, and a partial result of a partial multiplication of the first and second double-precision floating point numbers at the specialized processing block, wherein the partial result includes a first partial product, a sticky bit, and a round bit.
216
214
214
244
FIG. 2
For example, specialized processing block of may receive a portion of double-precision floating-point number A (e.g., signal A[54:28]), a portion of double-precision floating-point number B (e.g., signal B[54:28]), and a partial result from specialized processing block . The partial result may include the partial product computed by specialized processing block as well as a sticky bit and a round bit that were generated by inter-block signaling circuit .
1020
226
216
FIG. 2
During operation , the specialized processing block may multiply the first portion of the first double-precision floating-point number with the second portion of the second double-precision floating-point number to determine a second partial product. For example, multiplier in specialized processing block of may multiply signal A[54:28] with signal B[54:28] to generate a second partial product.
1030
236
216
226
214
FIG. 2
During operation , the specialized processing block may generate a plurality of results based on the second partial product and the partial result. For example, adder in specialized processing block of may generate a sum-plus-zero signal, a sum-plus-one signal, and a sum-plus-two signal based on the output of multiplier and the partial product from specialized processing block .
1040
216
214
During operation , the specialized processing block may determine a double-precision floating-point multiplication result by selecting among the plurality of results based at least in part on the sticky bit and the round bit. For example, specialized processing block may select between the sum-plus-zero signal, the sum-plus-one signal, and the sum-plus-two signal based on the round bit and the sticky bit received from specialized processing block .
The method and apparatus described herein may be incorporated into any suitable circuit or system of circuits. For example, the method and apparatus may be incorporated into numerous types of devices such as microprocessors or other integrated circuits. Exemplary integrated circuits include programmable array logic (PAL), programmable logic arrays (PLAs), field programmable logic arrays (FPGAs), electrically programmable logic devices (EPLDs), electrically erasable programmable logic devices (EEPLDs), logic cell arrays (LCAs), field programmable gate arrays (FPGAs), coarse-grained reconfigurable architectures (CGRAs), digital signal processing (DSP) circuits, application specific standard products (ASSPs), application specific integrated circuits (ASICs), just to name a few.
The integrated circuit described herein may be part of a data processing system that includes one or more of the following components: a processor; memory; I/O circuitry; and peripheral devices. The data processing system can be used in a wide variety of applications, such as computer networking, data networking, instrumentation, video processing, digital signal processing, or any suitable other application where the advantage of using circuitry that efficiently performs both, single-precision floating-point arithmetic operations and double-precision floating-point arithmetic operations, is desirable.
The integrated circuit may be configured to perform a variety of different logic functions. For example, the integrated circuit may be configured as a processor or controller that works in cooperation with a system processor. The integrated circuit may also be used as an arbiter for arbitrating access to a shared resource in the data processing system. In yet another example, the integrated circuit may be configured as an interface between a processor and one of the other components in the system. In one embodiment, the integrated circuit may be one of the families of devices owned by the assignee.
Although the method operations were described in a specific order, it should be understood that other operations may be performed in between described operations, described operations may be adjusted so that they occur at slightly different times or described operations may be distributed in a system which allows the occurrence of the processing operations at various intervals associated with the processing.
The foregoing is merely illustrative of the principles of the embodiments and various modifications can be made by those skilled in the art without departing from the scope and spirit of the embodiments disclosed herein. The foregoing embodiments may be implemented individually or in any combination. The above described embodiments are presented for purposes of illustration and not of limitation, and the present invention is limited only by the claims that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a diagram of an illustrative specialized processing block for performing either fixed-point, single-precision floating-point, or double-precision floating-point operations in accordance with an embodiment.
FIG. 2
is a diagram of an illustrative plurality of specialized processing blocks arranged in a cascade chain that performs a double-precision floating-point multiplication of first and second double-precision floating-point numbers in accordance with an embodiment.
FIG. 3
is a diagram of an illustrative specialized processing block with a multiplier circuit, an adder circuit, and an inter-block signaling circuit in accordance with an embodiment.
FIG. 4
is a diagram of illustrative arithmetic operator circuit that performs single- and double-precision floating-point rounding in a specialized processing block in accordance with an embodiment.
FIG. 5
is a diagram of illustrative arithmetic operator circuitry including a half-adder with two parallel prefix network trees in accordance with an embodiment.
FIG. 6
is a diagram of illustrative arithmetic operator circuitry for computing sum-plus-one in accordance with an embodiment.
FIG. 7
is a diagram of illustrative arithmetic operator circuitry for computing sum-plus-two in accordance with an embodiment.
FIG. 8
is a diagram of illustrative arithmetic operator circuitry for computing sum-plus-zero in accordance with an embodiment.
FIG. 9
is a diagram of illustrative arithmetic operator circuitry for computing and selecting among sum-plus-zero, sum-plus-one, and sum-plus-one in accordance with an embodiment.
FIG. 10
is a diagram of a flow chart showing illustrative steps for operating a specialized processing block in accordance with an embodiment. | |
The centroid-based model for extractive document summarization is a simple and fast baseline that ranks sentences based on their similarity to a centroid vector. In this paper, we apply this ranking to possible summaries instead of sentences and use a simple greedy algorithm to find the best summary. Furthermore, we show possibilities to scale up to larger input document collections by selecting a small number of sentences from each document prior to constructing the summary. Experiments were done on the DUC2004 dataset for multi-document summarization. We observe a higher performance over the original model, on par with more complex state-of-the-art methods.
1 Introduction
Extractive multi-document summarization (MDS) aims to summarize a collection of documents by selecting a small number of sentences that represent the original content appropriately. Typical objectives for assembling a summary include information coverage and non-redundancy. A wide variety of methods have been introduced to approach MDS.
Many approaches are based on sentence ranking, i.e. assigning each sentence a score that indicates how well the sentence summarizes the input Erkan and Radev (2004); Hong and Nenkova (2014); Cao et al. (2015). A summary is created by selecting the top entries of the ranked list of sentences. Since the sentences are often treated separately, these models might allow redundancy in the summary. Therefore, they are often extended by an anti-redundancy filter while de-queuing ranked sentence lists.
Other approaches work at summary-level rather than sentence-level and aim to optimize functions of sets of sentences to find good summaries, such as KL-divergence between probability distributions Haghighi and Vanderwende (2009) or submodular functions that represent coverage, diversity, etc. Lin and Bilmes (2011)
The centroid-based model belongs to the former group: it represents sentences as bag-of-word (BOW) vectors with TF-IDF weighting and uses a centroid of these vectors to represent the whole document collection Radev et al. (2004). The sentences are ranked by their cosine similarity to the centroid vector. This method is often found as a baseline in evaluations where it usually is outperformed Erkan and Radev (2004); Hong et al. (2014).
This baseline can easily be adapted to work at the summary-level instead the sentence level. This is done by representing a summary as the centroid of its sentence vectors and maximizing the similarity between the summary centroid and the centroid of the document collection. A simple greedy algorithm is used to find the best summary under a length constraint.
In order to keep the method efficient, we outline different methods to select a small number of candidate sentences from each document in the input collection before constructing the summary.
We test these modifications on the DUC2004 dataset for multi-document summarization. The results show an improvement of Rouge scores over the original centroid method. The performance is on par with state-of-the-art methods which shows that the similarity between a summary centroid and the input centroid is a well-suited function for global summary optimization.
The summarization approach presented in this paper is fast, unsupervised and simple to implement. Nevertheless, it performs as well as more complex state-of-the-art approaches in terms of Rouge scores on the DUC2004 dataset. It can be used as a strong baseline for future research or as a fast and easy-to-deploy summarization tool.
2 Approach
2.1 Original Centroid-based Method
The original centroid-based model is described by Radev et al. (2004). It represents sentences as BOW vectors with TF-IDF weighting. The centroid vector is the sum of all sentence vectors and each sentence is scored by the cosine similarity between its vector representation and the centroid vector. Cosine similarity measures how close two vectors and are based on their angle and is defined as follows:
|(1)|
A summary is selected by de-queuing the ranked list of sentences in decreasing order until the desired summary length is reached.
Rossiello et al. (2017) implement this original model with the following modifications:
-
In order to avoid redundant sentences in the summary, a new sentence is only included if it does not exceed a certain maximum similarity to any of the already included sentences.
-
To focus on only the most important terms of the input documents, the values in the centroid vector which fall below a tuned threshold are set to zero.
This model, which includes the anti-redundancy filter and the selection of top-ranking features, is treated as the ”original” centroid-based model in this paper.
We implement the selection of top-ranking features for both the original and modified models slightly differently to Rossiello et al. (2017): all words in the vocabulary are ranked by their value in the centroid vector. On a development dataset, a parameter is tuned that defines the proportion of the ranked vocabulary that is represented in the centroid vector and the rest is set to zero. This variant resulted in more stable behavior for different amounts of input documents.
2.2 Modified Summary Selection
The similarity to the centroid vector can also be used to score a summary instead of a sentence. By representing a summary as the sum of its sentence vectors, it can be compared to the centroid, which is different from adding centroid-similarity scores of individual sentences.
With this modification, the summarization task is explicitly modelled as finding a combination of sentences that summarize the input well together instead of finding sentences that summarize the input well independently. This strategy should also be less dependent on anti-redundancy filtering since a combination of redundant sentences is probably less similar to the centroid than a more diverse selection that covers different prevalent topics.
In the experiments, we will therefore call this modification the ”global” variant of the centroid model. The same principle is used by the KLSum model Haghighi and Vanderwende (2009) in which the optimal summary minimizes the KL-divergence of the probability distribution of words in the input from the distribution in the summary. KLSum uses a greedy algorithm to find the best summary. Starting with an empty summary, the algorithm includes at each iteration the sentence that maximizes the similarity to the centroid when added to the already selected sentences. We also use this algorithm for sentence selection. The procedure is depicted in Algorithm 1 below.
2.3 Preselection of Sentences
The modified sentence selection method is less efficient than the orginal method since at each iteration the score of a possible summary has to be computed for all remaining candidate sentences. It may not be noticeable for a small number of input sentences. However, it would have an impact if the amount of input documents was larger, e.g. for the summarization of top-100 search results in document retrieval.
Therefore, we explore different methods for reducing the number of input sentences before applying the greedy sentence selection algorithm to make the model more suited for larger inputs. It is also important to examine how this affects Rouge scores.
We test the following methods of selecting sentences from each document as candidates for the greedy sentence selection algorithm:
N-first
The first sentences of the document are selected. This results in a mixture of a lead- baseline and the centroid-based method.
N-best
The sentences are ranked separately in each document by their cosine similarity to the centroid vector, in decreasing order. The best sentences of each document are selected as candidates.
New-TF-IDF
Each sentence is scored by the sum of the TF-IDF scores of the terms that are mentioned in that sentence for the first time in the document. The intuition is that sentences are preferred if they introduce new important information to a document.
Note that in each of these candidate selection methods, the centroid vector is always computed as the sum of all sentence vectors, including the ones of the ignored sentences.
3 Experiments
Datasets
For testing, we use the DUC2004 Task 2 dataset from the Document Understanding Conference (DUC). The dataset consists of 50 document clusters containing 10 documents each. For tuning hyperparameters, we use the CNN/Daily Mail dataset Hermann et al. (2015) which provides summary bulletpoints for individual news articles. In order to adapt the dataset for MDS, 50 CNN articles were randomly selected as documents to initialize 50 clusters. For each of these seed articles, 9 articles with the highest word-overlap in the first 3 sentences were added to that cluster. This resulted in 50 documents clusters, each containing 10 topically related articles. The reference summaries for each cluster were created by interleaving the sentences of the article summaries until a length contraint (100 words) was reached.
Baselines & Evaluation
Hong et al. (2014) published SumRepo, a repository of summaries for the DUC2004 dataset generated by several baseline and state-of-the-art methods
Preprocessing
In the summarization methods proposed in this paper, the preprocessing includes sentence segmentation, lowercasing and stopword removal.
Parameter Tuning
The similarity threshold for avoiding redundancy () and the vocabulary-included-in-centroid ratio () are tuned with the original centroid model on our development set. Values from to with step size were tested using a grid search. The optimal values for and were and , respectively. These values were used for all tested variants of the centroid model. For the different methods of choosing sentences of each document before summarization, we tuned separately for each, with values from to , using the global model. The best found for -first, -best, new-tfidf were 7, 2 and 3 respectively.
Results
Table 1 shows the Rouge scores measured in our experiments.
The first two sections show results for baseline and SOTA summaries from SumRepo. The third section shows the summarization variants presented in this paper. ”G” indicates that the global greedy algorithm was used instead of sentence-level ranking. In the last section, ”- R” indicates that the method was tested without the anti-redundancy filter.
Both the global optimization and the sentence preselection have a positive impact on the performance.
The global + new-TF-IDF variant outperforms all but the DPP model in Rouge-1 recall. The global + N-first variant outperforms all other models in Rouge-2 recall. However, the Rouge scores of the SOTA methods and the introduced centroid variants are in a very similar range.
Interestingly, the original centroid-based model, without any of the new modifications introduced in this paper, already shows quite high Rouge scores in comparison to the other baseline methods. This is due to the anti-redundancy filter and the selection of top-ranking features.
In order to see whether the global sentence selection alleviates the need for an anti-redundancy filter, the original method and the global method (without sentences per document selection) were tested without it (section 4 in Table 1). In terms of Rouge-1 recall, the original model is clearly very dependent on checking for redundancy when including sentences, while the global variant does not change its performance much without the anti-redundancy filter. This matches the expectation that the globally motivated method handles redundancy implicitly.
4 Example Summaries
Table 2 shows generated example summaries using the global centroid method with the three sentence preselection methods. For readability, truncated sentences (due to the 100-word limit) at the end of the summaries are excluded. The original positions of the summary sentences, i.e. the indices of the document and the sentence inside the document are given. As can be seen in the examples, the N-first method is restricted to sentences appearing early in documents. In the new-TF-IDF example, the second and third sentences were preselected because high ranking features such as ”robot” and ”arm” appeared for the first time in the respective documents.
5 Related Work
In addition to various works on sophisticated models for multi-document summarization, other experiments have been done showing that simple modifications to the standard baseline methods can perform quite well.
Rossiello et al. (2017) improved the centroid-based method by representing sentences as sums of word embeddings instead of TF-IDF vectors so that semantic relationships between sentences that have no words in common can be captured. Mackie et al. (2016) also evaluated summaries from SumRepo and did experiments on improving baseline systems such as the centroid-based and the KL-divergence method with different anti-redundancy filters. Their best optimized baseline obtained a performance similar to the ICSI method in SumRepo.
6 Conclusion
In this paper we show that simple modifications to the centroid-based method can bring its performance to the same level as state-of-the-art methods on the DUC2004 dataset. The resulting summarization methods are unsupervised, efficient and do not require complicated feature engineering or training.
Changing from a ranking-based method to a global optimization method increases performance and makes the summarizer less dependent on explicitly checking for redundancy. This can be useful for input document collections with differing levels of content diversity.
The presented methods for restricting the input to a maximum of sentences per document lead to additional improvements while reducing computation effort, if global optimization is being used. These methods could be useful for other summarization models that rely on pairwise similarity computations between all input sentences, or other properties which would slow down summarization of large numbers of input sentences.
The modified methods can also be used as strong baselines for future experiments in multi-document summarization.
Footnotes
- http://www.cis.upenn.edu/~nlp/corpora/sumrepo.html
- ROUGE-1.5.5 with the settings -n 4 -m -a -l 100 -x -c 95 -r 1000 -f A -p 0.5 -t 0
References
- Ziqiang Cao, Furu Wei, Li Dong, Sujian Li, and Ming Zhou. 2015. Ranking with recursive neural networks and its application to multi-document summarization. In AAAI. pages 2153–2159.
- Günes Erkan and Dragomir R. Radev. 2004. Lexrank: Graph-based lexical centrality as salience in text summarization. Journal of Artificial Intelligence Research 22:457–479.
- Aria Haghighi and Lucy Vanderwende. 2009. Exploring content models for multi-document summarization. In Proceedings of Human Language Technologies: The 2009 Annual Conference of the North American Chapter of the Association for Computational Linguistics. Association for Computational Linguistics, pages 362–370.
- Karl Moritz Hermann, Tomas Kocisky, Edward Grefenstette, Lasse Espeholt, Will Kay, Mustafa Suleyman, and Phil Blunsom. 2015. Teaching machines to read and comprehend. In Advances in Neural Information Processing Systems. pages 1693–1701.
- Kai Hong, John M. Conroy, Benoit Favre, Alex Kulesza, Hui Lin, and Ani Nenkova. 2014. A repository of state of the art and competitive baseline summaries for generic news summarization. In LREC. pages 1608–1616.
- Kai Hong and Ani Nenkova. 2014. Improving the estimation of word importance for news multi-document summarization. In EACL. pages 712–721.
- Chin-Yew Lin. 2004. Rouge: A package for automatic evaluation of summaries. In Text summarization branches out: Proceedings of the ACL-04 workshop. Barcelona, Spain, volume 8.
- Hui Lin and Jeff Bilmes. 2011. A class of submodular functions for document summarization. In Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics: Human Language Technologies-Volume 1. Association for Computational Linguistics, pages 510–520.
- Stuart Mackie, Richard McCreadie, Craig Macdonald, and Iadh Ounis. 2016. Experiments in newswire summarisation. In European Conference on Information Retrieval. Springer, pages 421–435.
- Dragomir R. Radev, Hongyan Jing, Małgorzata Styś, and Daniel Tam. 2004. Centroid-based summarization of multiple documents. Information Processing & Management 40(6):919–938.
- Gaetano Rossiello, Pierpaolo Basile, and Giovanni Semeraro. 2017. Centroid-based text summarization through compositionality of word embeddings. MultiLing 2017 page 12. | https://www.groundai.com/project/revisiting-the-centroid-based-method-a-strong-baseline-for-multi-document-summarization/ |
If you've got delicate wallpaper, wrap the bristles in some toilet paper or paper towel and slightly wet it too. 4. Apply any scrub powder to especially dirty areas. If you've got lime and build-up in the tub, sink, or around faucets, damp those areas slightly and sprinkle with scrubbing powder like Comet. Letting it sit for 10-15 minutes while you do other things will help to work loose the... A rung wet towel, a bit of soap, and some old scrubbing. Don't soak the pad, as a lot of them have a glued/adhesive surface that will start to peel at the edges if you soak it enough. Don't soak the pad, as a lot of them have a glued/adhesive surface that will start to peel at the edges if you soak it enough.
If you've got delicate wallpaper, wrap the bristles in some toilet paper or paper towel and slightly wet it too. 4. Apply any scrub powder to especially dirty areas. If you've got lime and build-up in the tub, sink, or around faucets, damp those areas slightly and sprinkle with scrubbing powder like Comet. Letting it sit for 10-15 minutes while you do other things will help to work loose the how to draw a circuit diagram online A handful of wet newspaper doesn't hold together so well. Also, the ink from wet newspaper can rub off on molding and trim, requiring more cleaning. It can also leave ink on your hands, although with the switch to water-based inks and more absorbent newsprint, there's less transference these days.
Dirty finger marks or other clingy dirt may be lightly removed with a dampened wipe, moistened with the mild emulsion used to clean eyeglass lenses. Try it on a corner before swiping it across the entire print. Photo emulsion cleaner works the same way to remove the grime that's muddying the surface of the print. You also can try a cotton ball just moistened with a small amount of rubbing how to clean before moving in A handful of wet newspaper doesn't hold together so well. Also, the ink from wet newspaper can rub off on molding and trim, requiring more cleaning. It can also leave ink on your hands, although with the switch to water-based inks and more absorbent newsprint, there's less transference these days.
Wet some more paper towels and wipe away all the excess toothpaste, switching the dirty paper towels out for clean ones when necessary. Finish by rubbing a soft cloth over the damp board to dry and shine it.
A rung wet towel, a bit of soap, and some old scrubbing. Don't soak the pad, as a lot of them have a glued/adhesive surface that will start to peel at the edges if you soak it enough. Don't soak the pad, as a lot of them have a glued/adhesive surface that will start to peel at the edges if you soak it enough. | http://mazurpr.com/quebec/how-to-clean-dirty-wet-paper.php |
The fine separator comprises a connecting part and a screening cavity, the connecting part is provided with a first surface connected with a length-controlled screening hole screening plate, the screening cavity is arranged at one end of the connecting part and provided with a feeding port and a discharging port, the plane where the feeding port is located is coplanar with the first surface, and the discharging port is located on the second surface. The inner wall of the screening cavity is a rotating curved surface, the feeding port is an arc with a preset central angle, the feeding port is a rotating track of a first end point of a generatrix of the rotating curved surface around a rotating shaft, a second end point of the generatrix is located below the first end point, the generatrix of the rotating curved surface is an arc and is coplanar with the rotating shaft, and the rotating shaft is perpendicular to the plane where the feeding port is located. According to whether the rotating shaft passes through the circle center of the screening hole or a point on the circumference, whether the radius of the generatrix arc is L or L/2 and whether the circle center coincides with the circle center of the screening hole or is on the circumference, the fine classifiers a, b and c are subdivided, and the tobacco stem separation accuracy can be improved by additionally arranging a spherical crown and increasing the solid angle omega of the rotating curved surface. | |
Any macroscopic object we meet contains a large number of particles, each of which moves according to the laws of mechanics (which can be classical or quantum). Yet we can often ignore the details of this microscopic motion and use a few average quantities such as temperature and pressure to describe and predict the behaviour of the object. Why we can do this, when we can do this and how to do it are the subject of this module.
The most important idea in the field is due to Boltzmann, who identified the connection between entropy and disorder. The empirical laws of thermodynamics required the existence of entropy, but there was no microscopic definition for it. The module shows how the structure of equilibrium thermodynamics follows from Boltzmann's definition of the entropy and shows how, in principle, any observable equilibrium quantity can be computed. This microscopic theory (now called statistical mechanics) provides the basis for predicting and explaining all thermodynamic properties of matter.
The module introduces statistical mechanics and its central role in physics. It should give an appreciation of Boltzmann's insights into the nature and role of entropy. Many of the ideas introduced here will be used in the description of the properties of matter in solid state, nuclear and astrophysics modules.
Be familiar with the definition of thermal equilibrium, the ergodic hypothesis and the various ensembles.
Know the definition and importance of the partition function and be able to calculate thermodynamic averages from it. This includes the Fermi-Dirac and Bose-Einstein distributions.
Introduction to Statistical Mechanics: Systems and states: microstates. Fundamental assumptions of stat. mech.
Boltzmann distribution and Lagrange multipliers: Partition function, Z. Evaluation of Z for a spin-half system in a magnetic field and harmonic oscillator and system with degeneracy. Relationship of Z to thermodynamic quantities E, S and F=E-TS. Minimization of F in equilibrium for systems at fixed T and V. Microscopic basis for thermodynamics and relation to statistical mechanics.
Classical Thermodynamics of Gases: Thermal equilibrium, quasistatic and reversible changes. Statistical Mechanics of Classical Gases. Thermodynamic potentials G and H. The ideal gas law, the Gibbs paradox.
Grand-Canonical ensembles: system not closed (possibility of particle exchange between systems). Bose- Einstein and Fermi- Dirac distribution functions. Density of states. Chemical potential. Fermi energy. Relevance of Fermi-Dirac and Bose-Einstein to matter. Phonons: Einstein model, Debye model and dispersive phonons, role of elastic modulus, phonon heat capacity, thermal expansion. Thermal properties of the free Fermi gas.
There will be four examples sheets associated with the module with some problems to be done for assessment.
Assessment: 1 hour examination (85%) + assessed work (15%).
Recommended Texts: S. Blundell and K. Blundell, Concepts in Thermal Physics, OUP; M. Glazer and J. Wark, Statistical Mechanics - a survival guide, OUP; A.M. Guenault, Statistical Physics, Springer. | https://text.www2.warwick.ac.uk/fac/sci/physics/current/teach/syllabi/year2/px265/?external=true |
BACKGROUND OF THE INVENTION
SUMMARY OF THE INVENTION
SWASH PLATE ASSEMBLY EMBODIMENT
DOUBLE
YOKE ASSEMBLY EMBODIMENT DESCRIPTION
BRIEF DESCRIPTION OF THE DRAWINGS
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Swash Plate Embodiment - [Figures (1) through (8B)]
Double Yoke Embodiment - [Figures (9) through (18)]
Multiple Double Yoke Arrangements
TRANSMISSION LEVERAGE & ROTATIONAL MOTION ANALYSIS
The invention relates to a mechanical device that provides for an infinitely and continuously variable transmission system that is capable of gradually and smoothly multiplying TORQUE while decreasing RPM and vice-versa. For a given input shaft TORQUE and RPM, the system will deliver to the output shaft, through an infinite and continuous process, such increases or reductions in TORQUE with inversely corresponding increases or reductions in RPM as may be desired across a predetermined and very wide range of transmission ratios. The range can include zero RPM for the output shaft while the input shaft continues to rotate at any RPM, thus eliminating the need for an input shaft disengaging clutch. The infinitely and continuously variable TORQUE and RPM ratios are produced by causing a central assembly including a hub having one, two, three or more co-axial opposing pairs of short shafts which share the same plane with each other and with the hub's multi-directional center and which are radially and symmetrically mounted on its outer perimeter, to oscillate around some or all of such short shaft axes. Each short shaft coaxially carries at its outer end a one-way clutch "freewheel" that engages in one rotational direction of its carrying short shaft and disengages its carrying short shaft in the other direction. All such freewheels are in turn continuously and uni-directionally engaged to a common rotatable output gear which is caused to rotate through a simultaneous combination of the short shaft oscillations and their one way engagement/disengagement freewheel action. The central assembly is caused to oscillate either through gradually pivoting a rotating swash plate co-centrally mounted to and pressing against the oscillating central assembly through a thrust bearing or through gradually pivoting while rotatably displacing one pivotable and rotatably displacable yoke with respect to a second fixed and opposing yoke, wherein the yokes are connected to each other through the oscillating central assembly's short shafts.
The capability of the transmission to provide infinite and continuous increases or reductions in TORQUE with inversely corresponding increases or reductions in RPM is extremely desirable since it allows the selection of the exact TORQUE and RPM settings that may be required under any particular environment. This results in the most energy efficient transmission of power from the source to the load. At the same time, since the transmission described and claimed herein remains continuously engaged while shifting through the entire TORQUE and RPM range including the zero output RPM position, it totally eliminates the loss of power and/or momentum while down-shifting or up-shifting between gears which is inherent in today's manual and automatic gearboxes
Prior infinitely Variable Transmissions and continuously variable transmissions are generally of two types: "friction drive" transmissions and the "shaft oscillation" transmissions.
The "friction drive" transmissions rely mostly on conical pulleys and friction belts or cones with intermediate friction rollers, or toroidal discs with intervening friction rollers. All such devices are inherently "torque limited" and susceptible to unacceptable levels of wear and tear due to their reliance on friction.
The "shaft oscillation" transmissions rely on generating shaft oscillations generally through reciprocating or rotating cam followers oscillated by rotating cams. Such shaft oscillations rotate the output shafts through "one-way clutches" which engage when rotated in one direction and disengage when rotated in the opposite direction. Although such clutches are dependable, efficient and can sustain extremely heavy torque loads, the rotating or reciprocating cam followers together with their respective rotating cam arrangements disclosed thus far are too complex, are inefficient in that there are high friction losses associated with the multitude of moving parts, and are susceptible to very high wear and tear.
While the present invention may generally be considered to be of the "shaft oscillation" type, it overcomes the problems associated with prior art systems due to the inherent simplicity of its design, the total lack of cams and cam followers, and the fact that all moving parts and shafts rotate on ball bearings and/or thrust bearings throughout their entire range of motion.
light vehicles, heavy trucks, earth moving equipment, racing cars, motorcycles, wind generators, conveyor belts, production line machinery, marine propulsion
The additional advantages offered by the invention over existing technology include, but are not limited to: exceptional torque amplification (from over 90 to 1 down to 1 to 1) with associated RPM ranges from source RPM down to zero; no need for input shaft disengaging clutch; improved fuel economy; improved acceleration; improved matching of power transmission from source to load; improved reliability through use of few moving parts; low manufacturing costs due to the simplicity of parts; very compact volume and low weight; and an extremely broad range of applications including units, etc.
Swash Plate Assembly
- In one of the preferred embodiments of the invention at least one "swash-plate assembly" is utilized preferably having an inner circular rotating portion, an outer non-rotating partially hollow portion and a thrust bearing retention ring. The inner circular rotating portion has a central hub that contains a slot running radially through its center and a centrally positioned yoke-type retaining pin housing where the two exposed ends of the input shaft's retaining pin are rotatably mounted. The inner circular rotating portion is pivotally and centrally fixed by way of such central retaining pin housing and retaining pin to the input shaft, which runs horizontally through the center of the radial slot of such inner circular rotating portion thereby forcing it to co-rotate with the input shaft while at the same time allowing it to pivot with respect to the input shaft at any angle from zero degrees to over 25 degrees with respect to the vertical axis. The outer circular non-rotating partially hollow portion, is mounted concentrically to the inner rotating portion by way of an intervening main thrust bearing such that the inner rotating portion is rotatably driven by the input shaft and can freely rotate within the outer non-rotating partially hollow portion, thus causing the outer non-rotating partially hollow portion to exactly follow any motion, other than the motion of rotation, induced upon it by the inner rotating portion as its angle of pivot with respect to the input shaft is varied from the vertical. The thrust bearing retention ring is bolted on to the outer non-rotating partially hollow portion and holds the inner rotating portion, the intervening main thrust bearing and the outer non-rotating partially hollow portion together as one assembly through an auxiliary thrust bearing positioned between the thrust bearing retention ring and the inner rotating portion. The entire swash plate assembly pivots around the central retaining pin attached to the input shaft such that the longitudinal axis of the central retaining pin lies in the same plane that runs radially through the exact center of the main thrust bearing.
The outer non-rotating partially hollow portion of the swash plate assembly has four short radial shafts vertically fixed on its outer perimeter in a "cross pattern," each one of such four short radial shafts being positioned 90 degrees apart from its neighboring short shafts. The longitudinal axes of all four such short shafts lie on the same plane which plane in turn passes exactly through the point where the longitudinal axis of the central retaining pin of the swash plate assembly intersects with the longitudinal axis of the input shaft. Such four short shafts run in the north, south, east and west directions and are accordingly referred to as the "north", "south", "east", and "west" swash plate assembly short shafts.
Outer Ring
- The entire swash plate assembly is perimetrically surrounded by an outer ring that is concentrically mounted to the swash plate assembly and which is pivotally coupled to the swash plate assembly through the "north" and "south" swash plate assembly short shafts through related bearings. The outer ring has two of its own main shafts protruding outwards and vertically fixed to its outer perimeter in the "east" and "west" positions with respect to the "north" and "south" swash plate assembly short shafts. These two outer ring main shafts are in turn pivotally mounted in bearings that are part of the main frame, which allows the outer ring to pivot with respect to the main frame around the "east-west" axis. Concentrically mounted on each of the two outer ring main shafts between the outer ring and the main frame is a "freewheel" (one-way clutch) that carries a toothed gear concentrically mounted on its outer perimeter. Both of the toothed gears mounted perimetrically on the two freewheels are in turn continuously engaged with one main output gear which directly and simultaneously meshes with both said outer ring freewheel gears. The main output gear rotates concentrically with the input shaft but at varying rotation speeds and is connected to the output shaft either directly or through reduction gears.
Two Freewheel Swash Plate
- As the inner rotating portion of the swash plate assembly is forced to pivot with respect to the rotating input shaft, it causes the entire swash plate assembly to pivot with it. For example, as the angle of pivot of the swash plate assembly with respect to the rotating input shaft is varied from the vertical position (at zero degrees) to one degree, the rotation of the input shaft through 360 degrees forces the swash plate assembly's outer non-rotating partially hollow portion to which the four short shafts are perimetrically attached to oscillate around its "north-south" and "east-west" axes. As the swash plate assembly oscillates around the "east-west" axis it forces the outer ring to which it is attached through its "north" and "south" short shafts to also oscillate around its "east-west" axis. As the input shaft rotates by 360 degrees it will cause each of the outer ring's "east-west" main shafts to oscillate by 4 degrees (from minus 1 degree to zero to plus 1 degree and then back through zero to minus 1 degree). Accordingly each outer ring main shaft will engage its respective freewheel through 180 degrees of rotation of the input shaft and disengage its freewheel through the other 180 degrees of rotation of the input shaft. Since the two outer ring main shafts are opposed and their freewheels are equally opposed, when the freewheel of the east main shaft is engaged the freewheel of the west main shaft will be disengaged and vice-versa. Accordingly one freewheel will positively engage the main output gear through the first 180 degrees of rotation of the input shaft and the opposite freewheel will positively engage the main output gear through the other 180 degrees of rotation of the input shaft, thus producing rotary motion of the main output gear.
The Spider
- The basic transmission motion having a two freewheel swash plate assembly configuration relies solely on the oscillation of the swash plate assembly over its "east-west" axis. However, the swash plate assembly also oscillates over its "north-south" axis. This oscillation is transferred to the main output gear through an assembly called the spider. The spider has two sets of double legs (each set being much like a yoke) set 90 degrees apart and connected to each other through a common hub. It effectively resembles two yokes one superimposed over the other and set 90 degrees out of phase with each other. The inner yoke of the spider is pivotally mounted through simple bearings to the "east-west" short shafts of the swash plate assembly while the outer yoke of the spider has two protruding main shafts vertically fixed at the end of each leg on its "north-south" axis, such that the center of such bearings and the longitudinal axis of such main shafts share the same plane. These two spider main shafts are in turn pivotally mounted in bearings that are set in the main frame, which allows the Spider to pivot with respect to the main frame around the "north-south" axis. Concentrically mounted on each of the two spider main shafts between the spider legs and the main frame is a freewheel (one way clutch) that carries a toothed gear concentrically mounted on its outer perimeter. Both of the two toothed gears mounted perimetrically on the two freewheels are in turn continuously engaged with the same main output gear which directly and simultaneously meshes with both said freewheel gears and the also with the two freewheel gears of the outer ring. The longitudinal axis of the two outer ring main shafts and the two spider main shafts all lie in one plane which is vertical to the input shaft and intersects the input shaft at the point of intersection of the longitudinal axes of the central retaining pin and the input shaft.
Four Freewheel Swash Plate
4
- In order to produce a continuous rotary motion of the main output gear, the "north-south" oscillation of the swash plate assembly must also be utilized in addition to its "east-west" oscillation. Accordingly, as the swash plate assembly oscillates around the "north-south" axis, it forces the spider to which it is attached through its "east" and "west" short shafts to also oscillate about its "north-south" axis. Given an angle of pivot of 1 degree, as the input shaft rotates by 360 degrees, the spider's two "north-south" main shafts begin to oscillate by degrees (from minus 1 degree to zero to plus 1 degree and then back through zero to minus 1 degree) thereby in turn intermittently engaging and disengaging each of their two freewheels every 180 degrees of rotation of the input shaft. Since the spider's two main shafts are opposed and their freewheels are equally opposed, when the freewheel of the north main shaft is engaged the freewheel of the south main shaft will be disengaged and vice-versa. Accordingly one freewheel will positively engage the main output gear through the first 180 degrees of rotation of the input shaft and the opposite freewheel will positively engage the main output gear through the other 180 degrees of rotation of the input shaft thus producing rotary motion of the main output gear. The combination of the positive main output gear intermittent engagement by the two "north-south" freewheels of the spider and the two "east- west" freewheels of the outer ring set 90 degrees out of phase with each other will cause the main output gear to rotate in a continuous and fluent motion at input shaft speeds equal to or in excess of 1,000 RPM, since each freewheel will positively engage the main output gear for only 90 degrees at a time (instead of 180 degrees) before its neighboring freewheel takes over by positively engaging the main output gear.
Six Freewheel Swash Plate
- In this configuration the swash plate assembly oscillates around three axis set 60 degrees out of phase to each other instead of oscillating around two axes set 90 degrees out of phase to each other as in the "Two" and "Four" Freewheel Swash Plate examples described previously. The three axes can be described as the "east-west" or "0-180" degree axis; the "southeast-northwest" or "60-240" degree axis; and the "southwest-northeast" or "120-300" degree axis. This configuration includes one central swash plate assembly, two outer rings and two spiders.
The swash plate assembly has two pairs of opposed short shafts vertically embedded on its outer perimeter, where one pair of opposed short shafts is fixed at the "0" and "180" degree positions and is pivotally mounted to the "0" and "180" orifices of Ring(A) and the other pair of opposed short shafts is fixed at the "90" and "270" degree positions and is pivotally mounted to Spider(A)'s "90" and "270" degree leg orifices. Ring(A) has two pairs of opposed short shafts vertically embedded on its outer perimeter where one pair of opposed shafts is fixed at the "60" and "240" degree positions and is pivotally mounted to the "60" and "240" degree orifices of Ring(B) and the other pair of opposed shafts is fixed at the "150" and "330" degree positions and is pivotally mounted to Spider(B)'s "150" and "330" degree leg orifices. Ring(B), Spider(A) and Spider(B) each have one pair of protruding opposed main shafts vertically embedded on their outer perimeter/legs at the "120"/"300" "O"/"180" and "60"/"240" degree positions, respectively, which are in turn pivotally mounted in bearings set in the main frame, thus allowing Ring(B), Spider(A) and Spider(B) to freely pivot with respect to the main frame around their "120-300", "0-180" and "60-240" main axes respectively. Concentrically mounted on each of such main shafts between respectively Ring(B), Spider(A) and Spider(B) and the main frame is a freewheel (one way clutch) that carries a toothed gear concentrically mounted on its outer perimeter. All six such toothed freewheel gears are in turn continuously engaged with the main output gear which rotates concentrically with the input shaft but at varying rotation speeds and is in turn connected to the output shaft either directly or through reduction gears.
As the swash plate assembly is pivoted with respect to the rotating input shaft away from the vertical, it induces oscillation of Ring(B)'s "120-300" main shafts, Spider(A)'s "0-180" degree main shafts and Spider(B)'s "60-240" degree main shafts, which causes their attached freewheels to intermittently positively and uni-directionally engage the main output gear with which they all mesh so that the main output gear rotates in a continuous and fluent motion.
Double Yoke Assembly
- In another embodiment of the invention, at least one double yoke assembly is utilized, preferably having a fixed yoke, a pivotable second yoke and a central cross assembly connecting the two opposed yokes to each other fork-to-fork. The fixed yoke has a central shaft which is rigidly mounted to the embodiment's rear frame such that it cannot either rotate or be rotatably displaced. The pivotable second yoke has an attached pivotable yoke shaft which cannot rotate but can be rotatably displaced through motions induced upon it, thereby causing it to oscillate on two axes (the "north-south" and "east-west" axes) with respect to the fixed yoke to which it is mounted fork-to-fork by way of the central cross assembly. The central cross assembly includes a central hollow hub having one pair of two opposed co-axial main shafts radially and rigidly mounted on its outer perimeter in the "north-south" axis, which are rotatably mounted through the fixed yoke's "north-south" axis orifices and whose shaft ends are rotatably housed in the embodiment's main frame in "north-south" alignment, and another pair of two coaxial opposing short shafts radially and rigidly mounted on its outer perimeter in the "east-west" axis, which are rotatably connected to the pivotable yoke's "south-east" axis orifices, all such main and short shafts being co-planar to each other such that their theoretical extensions intersect each other vertically at the same point as the hub's multi-directional center. Concentrically mounted on each of the two "north-south" main shafts between the fixed yoke's "north-south" fork ends and the main frame is a freewheel having a toothed gear concentrically mounted on its outer perimeter such that both freewheel gears are in turn continuously engaged with one main output gear that rotates concentrically with the axis of the central fixed yoke shaft and is preferably connected to the output shaft through a reduction gear.
Rotating Grooved Disc Driven By Input Shaft
- A rotating grooved disc that is driven by the power source is rotatably mounted on the front frame and is connected with the pivotable second yoke's central shaft end through an arc shaped groove. The free end of the pivotable yoke shaft is slidably mounted in the arc shaped groove through a sliding shoe rotatably fitted to its end such that the pivotable yoke shaft can be smoothly displaced (shifted) throughout the length of the arc shaped groove from being perfectly aligned with the grooved disc's central shaft until it is over 30 degrees out of alignment with the shaft while the grooved disc is rotating. Such displacement (shifting) is achieved through an extension arm being either screwed-in or screwed-out through a hollow central section of the pivotable yoke shaft, thereby forcing a pivotable and rotatable sliding bogie attached to its end to slide radially in or out the straight grooved track of the grooved rotating disc that is aligned with and lies directly behind the arc shaped groove.
Two Freewheel Double Yoke Arrangment
- The pivotable yoke is caused to oscillate around the "north-south" and "east-west" axes of the central cross assembly when the inclination angle of the pivotable yoke shaft with respect to the axis of rotation of the rotating grooved disc is varied from the horizontal position (zero degrees). The "east-west" oscillation of the pivotable yoke shaft causes the central cross assembly to which it is rotatably attached through the "east-west" short shafts to oscillate strictly and only around its "north-south" axis. Given an inclination angle of 1 degree, as the grooved disc rotates by 360 degrees it will cause the central cross assembly's "north-south" main shafts to oscillate by 4 degrees (from minus 1 degree to zero to plus 1 degree through zero to minus 1 degree). Since the two central cross assembly main shafts are opposed and their freewheels are equally opposed, one freewheel will positively engage the main output gear through the first 180 degrees of rotation of the grooved disc and the opposite freewheel will positively engage the main output gear through the other 180 degrees of rotation of the grooved disc thus producing rotary motion of the main output gear.
The Oscillating Horse Shoe
- An assembly called the horse shoe transforms the pivotable yoke shaft's "north-south" oscillation to an "east-west" axial oscillation whose axis is co-planar to the central cross assembly's "north-south" main shaft axis, which it vertically intersects at the point of intersection of the central cross assembly's "north-south" and "east-west" shaft axes. The horse shoe is aligned in the "east-west" direction and includes a central hollow semi-circular section through which the pivotable yoke's shaft is slidably mounted such that it can oscillate within such hollow section though a 60 degree arc in the "east-west" direction. A pair of "east-west", opposed, protruding, co-axial main shafts are rigidly and vertically attached to the horse shoe's ends such that the ends of said two main shaft are rotatably housed in the embodiment's main frame in "east-west" alignment.
The two main shafts of the central cross assembly and the two main shafts of the horse shoe are thus co-planar, their theoretical extensions vertically intersecting each other at a point co-incidental to the point of intersection of the central cross assembly's main "north-south" shafts and short "east-west" shafts. Concentrically mounted on each of the horse shoe's "east-west" main shafts between the horse shoe legs and the main frame is a freewheel that carries a toothed gear concentrically mounted on its outer perimeter such that both freewheel gears are in turn continuously engaged with the same main output gear to which are engaged the two freewheel gears attached to the central cross assembly's main "north-south" shafts.
Four Freewheel Double Yoke Arrangement
- As the pivotable yoke shaft oscillates in the "north-south" direction it forces the horse shoe to which it is slidably attached to oscillate strictly around the "east-west" axis of its two main "east-west" shafts. Given an inclination angle of 1 degree, as the grooved disc rotates by 360 degrees it will cause the horse shoe's "east-west" main shafts to oscillate by 4 degrees (from minus 1 degree to zero to plus 1 degree back through zero minus 1 degree). Since the horse shoe's two main shafts are opposed and their freewheels are equally opposed one freewheel will positively engage the main output gear through the first 180 degrees of rotation of the grooved disc and the opposite freewheel will positively engage the main output gear through the other 180 degrees of rotation of the grooved disc. The combination of the intermittent engagement of the main output gear by the horse shoe's two "east-west" freewheel gears and the cross assembly's two "north-south" freewheel gears set 90 degrees out of phase with each other will cause the main output gear to rotate in a continuous and very fluent motion.
Figures(1) through (8B)
relate to one preferred embodiment utilizing the Swash Plate Assembly.
Figure (1)
exploded view
is an of the swash plate assembly coupled to the outer ring and the spider including the input shaft and the parts associated with the shifting mechanism.
Figure(1A)
exploded view
is an of the input shaft assembly including some elements of the swash plate pivoting mechanism.
Figure(1B)
exploded view
is an of the back and front sides of the swash plate assembly's circular rotating portion.
Figure(2)
side view
is a schematic of the cross section of the entire assembled four freewheel single swash plate embodiment wherein the four freewheels are 90 degrees out of phase with each other and the applied swash plate inclination angle is set at zero degrees off the vertical.
Figure(2A)
side view
is a schematic of the cross section of the entire assembled four freewheel single swash plate embodiment having an applied swash plate inclination angle while the shifting linkage connecting the input shaft to the swash assembly's inner rotating portion is facing north.
Figure(3)
top view
is a schematic of the cross section of the swash plate and freewheel assembly of the four freewheel single swash plate embodiment with the applied swash plate inclination angle set at zero degrees off the vertical.
Figure(3A)
top view
is a schematic of the cross section of the swash plate and freewheel assembly of the four freewheel single swash plate embodiment having an applied swash plate inclination angle while the shifting linkage connecting the input shaft to the swash assembly's inner rotating portion is facing east.
Figure(4)
c front view
is a schemati of the cross section of the swash plate and freewheel assembly of the four freewheel single swash plate embodiment with the applied swash plate inclination angle set at zero degrees off the vertical.
Figure(5)
front view
is a schematic of the cross section of the swash plate and freewheel assembly of the two freewheel single swash plate embodiment with the applied swash plate inclination angle set at zero degrees off the vertical.
Figure(5A)
side view
is a schematic of the cross section of the swash plate and freewheel assembly of the two freewheel single swash plate embodiment with the applied swash plate inclination angle set at zero degrees off the vertical.
Figure(6)
front view
is a schematic of the cross section of the swash plate and freewheel assembly of the six freewheel single swash plate embodiment including two outer rings and two spiders with the applied swash plate inclination angle set at zero degrees off the vertical.
Figure(7)
side view
is a schematic of two opposed sets of the four freewheel swash plate assembly set 45 degrees out of phase with each other wherein the four freewheels of the left swash plate assembly set engage the left side of a common main output gear and the four freewheels of the right swash plate assembly set engage the right side of the common main output gear.
Figure(7A)
side view
is a schematic of the inner circular rotating portions of the swash plate assemblies of Figure(7) showing their 45 degree out of phase mounting to the common input shaft.
Figure(7B)
front view
is a schematic of the inner circular rotating portions of Figure(7A) showing their 45 degree out of phase mounting to the common input shaft.
Figure(8)
side view
is a schematic of two opposed sets of the two freewheel swash plate assembly set 90 degrees out of phase with each other wherein the two freewheels of the left swash plate assembly set engage the left side of a common main output gear and the two freewheels of the right swash plate assembly set engage the right side of the common main output gear.
Figure(8A)
side view
is a schematic of the inner circular rotating portions of the swash plate assemblies of Figure(8) showing their 90 degree out of phase mounting to the common input shaft.
Figure(8B)
front view
is a schematic of the inner circular rotating portions of Figure(8A) showing their 90 degree out of phase mounting to the common input shaft.
Figures (9) through (18)
relate to one preferred embodiment utilizing the Double Yoke Assembly.
Figure(9)
side view
is a schematic of the entire "two freewheel" double yoke embodiment.
Figures (10) and (10A)
side view
front view
depict the and respectively of the central cross assembly.
Figures(11), (11A) and (11B)
front view
side views
depict the and two respectively of the rotating grooved disc driven by the input source.
Figures(12), (12A), (12B) and (12C)
side view, side cross section(a), transverse cross section
side cross section(b)
depict the and respectively of the pivotable second yoke and yoke shaft.
Figure(13)
side cross
depicts the section of the pivotable second yoke's extension arm.
Figures(14) and (14A)
front view
side view
depict the and the respectively of the pivotable and rotatable sliding bogie.
Figures(15), (15A), (15B) and (15C)
side cross section, front view, rear view
top view
depict the and respectively of the oscillating horse shoe.
Figure(16)
side view
is a schematic of the entire "four freewheel" double yoke embodiment.
Figure (17)
is a schematic frontal cross section of the four freewheel double yoke embodiment's common plane shared by the four main freewheel shafts.
Figure (18)
side view
is a schematic of the entire "eight freewheel" double yoke embodiment.
Swash Plate Assembly:
Referring to FIG. (1), there is shown one of the preferred embodiments of the invention utilizing a swash plate assembly. The swash plate assembly includes an inner circular rotating portion (3), a concentrically mounted outer non-rotating partially hollow portion (5), and a thrust bearing retention ring (1) which is perimetrically attached to the outer non-rotating portion (5) thereby rotatably sandwiching the main thrust bearing (4), the inner rotating portion (3) and the auxiliary thrust bearing (2) in that order between the outer non-rotating partially hollow portion (5) and its attached thrust bearing retention ring (1). Assembled items (1,2,3,4 and 5) shall hereinafter be collectively referred to as the "swash plate assembly".
The inner rotating portion (3) has a central hub which contains a slot (46) running radically through its center and a centrally positioned yoke-type retaining pin housing (47) per FIG.(1B). The two exposed ends of the central retaining pin (44) of the input shaft (6) are rotatably mounted in the two opposed orifices (48) per FIG.(1B), thereby forcing the inner rotating portion (3) to co-rotate with the input shaft (6) while at the same time the inner rotating portion (3) may be pivoted with respect to the input shaft (6) at any angle from 0 degrees (vertical) to over 25 degrees from vertical with respect to the input shaft. The inner retaining portion (3) rotatably driven by the input shaft (6) can freely rotate within the outer non-rotating partially hollow portion (5) thus causing the outer non-rotating partially hollow portion (5) to exactly follow any motion, other than the motion of rotation, induced upon it by the inner rotating portion (3), as its angle of pivot with respect to the input shaft (6) is varied from the vertical. The entire swash plate assembly pivots around the central retaining pin (44) attached to the input shaft (6) such that the longitudinal axis of the central retaining pin (44) lies in the same plane that runs radially through the exact center of the main thrust bearing (4).
The outer non-rotating partially hollow portion (5) of the swash plate assembly has two pairs of opposed short shafts (7,8,9 and 10) radially and vertically fixed on its outer perimeter in a cross pattern such that each of such four short shafts lies 90 degrees apart from its neighboring short shafts. The longitudinal axis (7-8) running "east-west" and the longitudinal axis (9-10) running "north-south" of each pair of such opposed short shafts share the same plane with each other and with the point where the longitudinal axis of the central retaining pin (44) intersects with the longitudinal axis of the input shaft (6).
Pivot Mechanism:
The swash plate assembly can be pivoted with respect to the longitudinal axis of input shaft (6) while the input shaft is rotating. This is achieved through the linkage system consisting of the anchoring yoke (23) fixed to the swash plate assembly's inner rotating portion (3) through orifice (33) and pivotably connected to one end of lever arm (24) whose other end is pivotably connected to anchoring yoke (25) which is fixed to sliding carrier (26). Sliding carrier (26) is slidably mounted through its central orifice around input shaft (6) but is forced to co-rotate with input shaft (6) through a longitudinal recessed keyway machined in its central orifice which is aligned with a corresponding protruding rib (45) per FlG.(1A) longitudinally fixed on the surface of the input shaft (6) ninety degrees out of phase with respect to the axis of central retaining pin (44). A hollow rotatable flange (27) having two diametrically opposed orifices (28) and (29) is rotatably mounted on sliding carrier (26) and retained in place through the threaded end nut (30). Input shaft (6) is mounted through the front frame (60) per FlG.(2) of the embodiment by way of bearing (43) per FlG.(1A) which is rotatably fixed at its approximate mid-length point.
Sliding carrier (26) with hollow rotatable flange (27) and end nut (30) are mounted on the internal section of input shaft (6) while rotatable carrier (34), which is rotatably and slidably mounted to the external section of input shaft (6), together with shifting lever (40) and shifting yoke (37, 38, 39) are mounted on the external section of input shaft (6). Hollow rotatable flange (27) of sliding carrier (26) is connected to rotatable carrier (34) through two parallel connector shafts (31) and (32) whose inward ends are fixed to orifices (28) and (29) of hollow rotatable flange (27) and whose outward ends are fixed to the two corresponding orifices (35) and (36) of rotatable carrier (34). Parallel connector shafts (31) and (32) are slidably mounted with respect to the embodiment's front frame (60) per FIG.(2) through orifices (61). Shifting lever (40) with its related shifting yoke (37, 38, 39) is rotatably attached through shaft (39) per FlG.(1) to bracket (62) per FlG.(2), which is mounted on frame (60). Shifting lever yoke legs (38) and (37) are slidably and rotatably mounted to carrier (34) through its two protruding pins (41) and (42). As shifting lever (40) is slidably displaced with respect to bracket (63) per FIG.(2), which is mounted on frame (60) it forces rotatable carrier (34) to slide in or out with respect to input shaft (6) in turn causing sliding carrier (26) to correspondingly slide in or out with respect to input shaft (6) while co-rotating with input shaft (6), thereby causing through the pivotable action of lever arm (24) the swash plate assembly's inner rotating portion (3) to pivot with respect to input shaft (6). The combination of rotation of input shaft (6) and the inducement of a pivot angle to inner rotating portion (3) with respect to input shaft (6) causes the swash plate assembly's outer non-rotating portion (5) to symmetrically and harmoniously oscillate about the "east-west" and "north-south" axes of its short shafts (7, 8, 9, 10).
Outer Ring:
The entire swash plate assembly is perimetrically surrounded by an outer ring (13) that is concentrically and pivotally coupled to the swash plate assembly through short shafts (9) and (10) pivotally mounted to outer ring (13) through opposed orifices (12) and (11), respectively, which are aligned with the "north-south" axis. Outer ring (13) has two co-axial main shafts (14) and (15) protruding radially outward and vertically fixed to its outer perimeter in "east-west" axis alignment. The outer ring's main shafts (14) and (15) are pivotally mounted to the main frame of the embodiment in orifices (97) and (98) per FlG.(3), FlG.(3A) and FIG.(5) through related bearings, thus allowing outer ring (13) to pivot with respect to main frame (60) per FlG.(5) around the "east-west" axis. Concentrically mounted on each of the outer ring's two main shafts (14) and (15) between outer ring (13) and the main frame (60) are one way clutches freewheels (51) and (94) per FIG.(5), which carry toothed gears concentrically mounted on their outer perimeters. Freewheel gears (51) and (94) are continuously engaged with one main output gear (52) per FIG.(5). Examples of such freewheels are the Stieber Heidelberg Freewheels, types NF, NFS and NSS. Main output gear (52) per FIG.(2) is rotatably mounted within main frame (60) through main bearing (53) and thrust bearings (54) and (55) per FlG.(2) and rotates concentrically with input shaft (6) but at varying rotation speeds. Main output gear (52) is connected either directly to output shaft (58) or through meshing reduction gears (56) and (59) to output shaft (99) per FIG.(2). Main output gear's main bearing (53) and thrust bearings (54) and (55) are held in place through a set of three retention rings (57) per FIG.(2).
Two Freewheel Swash Plate:
As inner rotating portion (3) of the swash plate assembly is forced to pivot with respect to input shaft (6), it causes the entire swash plate assembly to pivot with it as depicted in FlG.(2A), which is a "side view" and FlG.(3A) which is a "top view" of the swash plate embodiment. As input shaft (6) begins to rotate while inner rotating portion (3) is pivoted the entire swash plate assembly begins to oscillate about its "east-west" and "north-south" axes.
The swash plate assembly's oscillation about its "east-west" axis will cause outer ring (13) through its "north-south" coupling with the swash plate assembly to also oscillate about its "east-west" axis, thereby causing the outer ring's two main shafts (14) and (15) to also oscillate about their "east-west" axis. Referring to FlG.(5) and FlG.(5A), both of which depict an embodiment having two freewheels per swash plate assembly, as input shaft (6) rotates by 360 degrees with an applied pivot angle of 1 degree of inner rotatable portion (3), such rotation will cause each of outer ring's opposed main shafts (14) and (15) to oscillate by 4 degrees (from minus 1 degree to zero to plus 1 degree back through zero to minus 1 degree). Accordingly, each outer ring main shaft (14) and (15) will engage its respective freewheel (51) and (94) through 180 degrees of rotation of input shaft (6) and disengage its respective freewheel (51) and (94) through the other 180 degrees of rotation of input shaft (6). Since two main shafts (14) and (15) are diametrically opposed and their freewheels (51) and (94) are equally diametrically opposed, when freewheel (51) is engaged freewheel (94) will be disengaged and vice-versa. Accordingly, freewheels (51) and (94) will intermittently engage main output gear (52) through 180 degrees of rotation and intermittently disengage main output gear (52) through the other 180 degrees of rotation of input shaft (6), thus producing rotary motion of the main output gear (52).
Spider:
The swash plate assembly's oscillation about its "north-south" axis is converted to rotary motion of main output gear (52) through the "spider," which consists of inner yoke (16), outer yoke (20) and common hub (19) per FlG.(1). Inner yoke (16) and outer yoke (20) are mounted to common hub (19) 90 degrees out of phase to each other. Inner yoke (16) is pivotally mounted through orifices (17) and (18) to "east-west" short shafts (7) and (8) of outer non-rotatable portion (5). Outer yoke (20) has two protruding co-planar main shafts (21) and (22) fixed at the end of each leg and aligned with the "north-south" axis such that the center of orifices (17) and (18) and the longitudinal axis of co-planar main shafts (21) and (22) share the same plane. The spider's main shafts (21) and (22) are pivotally mounted to the embodiment's main frame (60) in orifices (95) and (96) per FIG.(2) and FlG.(4) through related bearings, thus allowing the spider to pivot with respect to main frame (60) per FlG.(2) around the "north-south" axis. Concentrically mounted on each of the spider's two main shafts (21) and (22) between outer yoke (20) and the main frame (60) are freewheels (49) and (50) per FlG.(4) which carry toothed gears concentrically mounted on their outer perimeters. Freewheel gears (49) and (50) are continuously engaged with main output gear (52) per FlG.(4).
Four Freewheel Swash Plate:
As the swash plate assembly oscillates around the "north-south" axis, it forces the spider to which it is attached through inner yoke orifices (17) and (18) to also oscillate around its "north-south" axis. As input shaft (6) rotates by 360 degrees with an applied pivot angle of 1 degree of inner rotatable portion (3), such rotation will cause each of the spider's main shafts (21) and (22) to oscillate from minus 1 degree through plus 1 degree back to minus 1 degree, thereby engaging their respective freewheels (49) and (50) through 180 degrees of rotation of input shaft (6) and disengaging their respective freewheels (49) and (50) through the other 180 degrees of rotation of input shaft (6). The combination of the positive intermittent engagement of main output gear (52) by freewheels (49) and (50) of the spider and freewheels (51) and (94) of outer ring (13) set 90 degrees out of phase with each other will cause main output gear (52) to rotate in a continuous and fluent motion at input shaft (6) speeds equal to or in excess of 1,000 RPM, each freewheel positively engaging main output gear (52) only every 90 degrees (instead of 180 degrees) before its neighboring freewheel positively engages main output gear (52).
Six Freewheel Swash Plate:
In this configuration, the swash plate assembly oscillates around three axis set 60 degrees out of phase to each other instead of oscillating around two axis set 90 degrees out of phase to each other as in the "Two" and "Four" Freewheel Swash Plate embodiments described previously. The three axes can be described as the "east-west" or "0-180" degree axis; the "southeast-northwest" or "60-240" degree axis and the "southwest-northeast" or "120-300" degree axis. This configuration includes one central swash plate assembly (shaded area), two outer rings (71) and (73) and two spiders (70) and (72) per FlG.(6).
Referring to FIG.(6) the swash plate assembly (shaded area) has two pairs of opposed short shafts (74-75) and (76-77) vertically embedded on its outer perimeter, where pair (74-75) is fixed at the "0" and "180" degree positions and is pivotally mounted to the "0" and "180" orifices of inner ring (71) and pair (76-77) is fixed at the "90" and "270" degree positions and is pivotally mounted to the "90" and "270" degree leg orifices of inner spider (72). Inner ring (71) has two pairs of opposed short shafts (80-81) and (82-83) vertically embedded on its outer perimeter where pair (82-83) is fixed at the "60" and "240" degree positions and is pivotally mounted to the "60" and "240" degree orifices of outer ring (73) and pair (80-81) is fixed at the "150" and "330" degree positions and is pivotally mounted to the "150" and "330" degree leg orifices of outer spider (70). Outer ring (73), inner spider (72) and outer spider (70) each have one pair of protruding opposed main shafts (86-87), (78-79) and (84-85) respectively, which are vertically embedded on their outer perimeter/legs at the "120"/"300", "0"/"180" and "60"/"240" degree positions, respectively which are in turn pivotally mounted in bearings set in the main frame, thus allowing outer ring (70), inner spider (72) and outer spider (70) to freely pivot with respect to the main frame around their "120-300", "0-180" and "60-240" main axes, respectively. Concentrically mounted on each of such main shafts (86),(87),(78),(79),(84) and (85) between outer ring (70), inner spider (72), outer spider (70) and the main frame are freewheels (66),(67),(69),(68),(64) and (65), respectively each of which carries a toothed gear concentrically mounted on its outer perimeter. Freewheel gears (66),(67),(69),(68),(64) and (65), are in turn continuously engaged with a common main output gear which rotates concentrically with the input shaft but at varying rotation speeds and is in turn connected to the output shaft either directly or through reduction gears.
As the swash plate assembly is pivoted with respect to the rotating input shaft (6) away from the vertical, oscillation of outer ring's main shafts (86) and (87), inner spider's main shafts (78) and (79) and outer spider's main shafts (84) and (85) is induced which causes their attached freewheels (66)-(67), (69)-(68) and (64-65) to intermittently positively and uni-directionally engage the common main output gear with which they all mesh, so that the main output gear rotates in a continuous and fluent motion.
Multiple Swash Plate Arrangements:
The two, four and six freewheel swash plates and various combinations thereof can be employed in order to meet specific requirements. Generally, the two and four freewheel swash plates described previously can accept pivot angles with respect to the rotating input shaft of up to about 15 degrees while the six freewheel swash plate described previously can accept higher pivot angles, thus allowing for a wider range of RPM ratios and TORQUE amplification factors.
Referring to FIG.(7), FIG.(7A) and FIG.(7b), two sets of four freewheel swash plate assemblies (89) and (90) can be co-axially but not co-rotatably placed each on either side of a double faced main output gear (88) driving an output shaft (91) such that the "north-south" freewheels of set (89) are positioned on the north-south "0-180" degree axis and the "north-south" freewheels of set (90) are positioned on the northeast-southwest "45-225" degree axis per FIG.(7B), thus being 45 degrees out of phase with each other. This arrangement offers an extremely smooth output gear rotation down to an input shaft rotation of below 500 RPM.
Referring to FIG.(8), FIG.(8A) and FIG.(8B), two sets of the two freewheel swash plate assemblies (92) and (93) can be co-axially but not co-rotatably placed each on either side of a double faced main output gear such that the "north-south" freewheels of set (92) are positioned on the "north-south" "0-180" degree axis and the "north-south" freewheels of set (93) are positioned on the "east-west" "90-180" degree axis per FIG.(8B) thus being 90 degrees out of phase with each other. This arrangement offers the same output gear rotation smoothness as a single four freewheel swash plate assembly but without the use of spiders.
Two sets of six freewheel swash plate assemblies can be co-axially but not co- rotatably placed each on either side of a double faced main output gear such that the "north-south" freewheels of the right set are positioned on the north-south "0-180" degree axis and the "north-south" freewheels of the left set are positioned on the northeast-southwest "30-210" degree axis thus being 30 degrees out of phase with each other. This arrangement offers an extremely smooth output gear rotation down to an input shaft rotation of well below 500 RPM and an expanded range of ratios from a bottom end of as low as (3 to 1] to a high end of as high as (90 to 1].
Swash plate arrangements having more than six freewheels each engaging one or more main output gears can be utilized to meet any extraordinary or other application requirements.
Double Yoke Assembly:
Referring to FIG.(9), there is shown another of the preferred embodiments of the invention utilizing a double yoke assembly wherein at least one double yoke assembly is utilized preferably having a fixed yoke (101), a pivotable second yoke (102) and a central cross assembly (103) connecting the two opposed yokes (101) and (102) to each other "fork to fork". The fixed yoke (101) has a central shaft which is rigidly mounted to the embodiment's rear frame (120) at position (121) thereby not allowing it to either rotate or be rotatably displaced. The pivotable second yoke (102) has an attached pivotable yoke shaft which cannot rotate but can be rotatably displaced through motions induced upon it, thereby causing it to oscillate about two axes (the "north-south" and "east-west" axes) with respect to the fixed yoke (101) to which it is mounted fork to fork by way of the central cross assembly (103). The central cross assembly (103) includes a central hollow hub (103) having one pair of two opposed coaxial main shafts (111) and (112) per FIG.(10) and (10A) radially and rigidly mounted on its outer perimeter in the "north-south" axis, which are rotatably mounted through the "north-south" axis orifices of the fixed yoke (101) and whose shaft ends (111) and (112) are rotatably housed in the embodiment's main frame (120) in "north-south" alignment and another pair of two co-axial opposing short shafts (122) and (123) per FIG.(10A) radially and rigidly mounted on its outer perimeter in the "east-west" axis, which are rotatably connected to the "east-west" axis of the pivotable yoke orifices (128) and (129) respectively per FIG.(12A) and (12B), wherein main shafts (111) and (112) and short shafts (122) and (123) are co-planar to each other such that their theoretical extensions intersect each other vertically at the same point as the hub's (103) multi-directional center. Concentrically mounted on each of main shafts (111) and (112) between the "north-south" fork ends of fixed yoke (101) and main frame (120) are freewheels (116) and (117), each having a toothed gear concentrically mounted on its outer perimeter such that both freewheel gears (116) and (117) are in turn continuously engaged with main output gear (113) which rotates concentrically with the axis of the central fixed yoke shaft (101) and is preferably connected to the output shaft (114) through a reduction gear (115).
Rotating Grooved Disc Driven By Input Shaft:
Rotating grooved disc (104), which is driven by the power source through input shaft (107) and reduction gear (108), is rotatably mounted on the front frame (120) and is connected with the pivotable second yoke's central shaft end (102) through an arc-shaped groove (105) as set out in detail in FIG.(11), (11A) and (11B). The free end of the pivotable yoke shaft (102) is slidably mounted in the arc-shaped groove (105) through sliding shoe (109) rotatably fitted to its end such that the pivotable yoke shaft (102) can be smoothly displaced (shifted) throughout the length of the arc shaped grove (105) from a position where it is perfectly aligned with the grooved disc's central shaft (119) until it is over 30 degrees out of alignment with the shaft while grooved disc (104) is rotating.
Pivot Arrangement of Pivotable Yoke Shaft:
Concentrically and threadably mounted to hollow sections (130) and (131) of pivotable yoke shaft (102) per FIG.(12), (12A), (12B), (12C) and FIG.(13) is yoke shaft extension arm (124), the free end of which is in turn attached to pivotable and rotatable sliding bogie (110) per FlG.(14) and (14A), The bogie (110) is slidably mounted in straight bogie track (106) of rotating grooved disc (104). As yoke shaft extension arm (124) is rotated by first rotatable shifting shaft (118) and its attachments per FlG.(9) and FIG.(12) it is either screwed-in or screwed out with respect to the pivotable yoke shaft (102) thereby causing yoke shaft extension arm (124) to extend outwards or inwards from the free end of pivotable yoke shaft (102). This in turn forces sliding bogie (110) radially outward or inward within straight bogie track (106) of rotating grooved disc (104), thus displacing pivotable yoke shaft (102) out of alignment and, respectively, back into alignment, with respect to the axis of rotation of the rotating grooved disc's shaft (119). The means of rotation of yoke shaft extension arm (124) are provided by a first rotatable shifting shaft (118) which passes through the hollow center of fixed yoke shaft (101) and is in turn attached to small universal joint (148) which passes through the hollow center of cross assembly hub (103). The center of pivot of small universal joint (148) is perfectly aligned with the point of intersection of the axes of main "north-south" shafts (111) and (112) and short "east-west" shafts (122) and (123). Small universal joint (148) is further attached to a second rotatable shifting shaft (149) which passes through hollow center (132) of the pivotable yoke shaft (102) such that the free ribbed "male end" of second shifting shaft (149) is slidably mounted in a central hollow ribbed recess "female end" running through the threaded section (150) of pivotable yoke shaft extension arm (124).
Two Freewheel Double Yoke Arrangement:
Pivotable yoke (102) is caused to oscillate around the "north-south" and "east-west" axes of central cross assembly (103) when the inclination angle of pivotable yoke shaft (102) with respect to the axis of rotation of rotating grooved disc (104) is varied from the (zero degree) horizontal position. The "east-west" oscillation of pivotable yoke shaft (102) causes central cross assembly (103) to which it is rotatably attached through "east-west" short shafts (122) and (123) to oscillate strictly and only around its "north-south" axis.
Given an inclination angle of 1 degree, as grooved disc (104) rotates by 360 degrees it will cause the central cross assembly's "north-south" main shafts (111) and (112) to oscillate by 4 degrees (from minus 1 degree through plus 1 degree back to minus 1 degree). Since main shafts (111) and (112) are opposed and their freewheels (116) and (117), respectively, are equally opposed, one freewheel will positively engage main output gear (113) through the first 180 degrees of rotation of grooved disc (104) and the opposite freewheel will positively engage main output gear (113) through the other 180 degrees of rotation of grooved disc (104) thus producing rotary motion of the main output gear (113).
The Oscillating Horse Shoe
: Horse shoe (125) per FIG.(15), (15A),(15B) and (15C) transforms pivotable yoke shaft's (102) "north-south" oscillation to an "east-west" axial oscillation whose axis is co-planar to the central cross assembly's (103) "north-south" main shaft axis which it vertically intersects at the point of intersection of the central cross assembly's "north-south" and "east-west" shaft axes. Horse shoe (125) is aligned in the "east-west" direction with respect to embodiment frame (120) when viewed from the front and includes a central hollow semi-circular section (134) through which pivotable yoke shaft (102) is slidably mounted through rollers (133) per FlG.(12A),(12B) and (12C), which are fitted on either of its sides such that pivotable yoke shaft (102) can oscillate within hollow section (134) though a 60 degree arc in the "east-west" direction with respect to frame (120). A pair of "east-west", opposed, protruding, co-axial main shafts (126) and (127) are rigidly and vertically attached to the ends of horse shoe (125) such that the ends of main shafts (126) and (127) are rotatably housed in main frame (120) in "east-west" alignment when viewed from the front. Central cross assembly main shafts (111) and (112) and horse shoe main shafts (126) and (127) share the same plane with each other, their theoretical extensions vertically intersecting each other at a point co-incidental to the point of intersection of main "north-south" shafts (111) and (112) and short "east-west" shafts (122) and (123) of central cross assembly (103).
Concentrically mounted on each horse shoe "east-west" main shaft (126) and (127) between horse shoe legs (125) and main frame (120) are freewheels (135) and (136) per FIG.(16) and FIG.(17) each of which carries a toothed gear concentrically mounted on its outer perimeter such that freewheel gears (135) and (136) are in turn continuously engaged with the same main output gear (113) to which freewheel gears (116) and (117) are also engaged.
Four Freewheel Double Yoke Arrangement
- As pivotable yoke shaft (102) oscillates in the "north-south" axis, it forces horse shoe (125) to which it is slidably attached to oscillate strictly around the "east-west" axis of its two main "east-west" shafts (126) and (127). Given an inclination angle of 1 degree, as grooved disc (104) rotates by 360 degrees it causes "east-west" main shafts (126) and (127) to oscillate by 4 degrees (from minus 1 degree through plus 1 degree back to minus 1 degree). Since main "east-west" shafts (126) and (127) are opposed and their freewheels (135) and (136) are equally opposed, one freewheel will positively engage main output gear (113) through the first 180 degrees of rotation of grooved disc (104) and the opposite freewheel will positively engage main output gear (113) through the other 180 degrees of rotation of grooved disc (104). The combination of the intermittent engagement of main output gear (113) by main "east-west" freewheel gears (135) and (136) and main "north-south" freewheel gears (116) and (117) set 90 degrees out of phase with each other will cause main output gear (113) to rotate in a continuous and very fluent motion.
The geometry of the two and four freewheel double yoke embodiments provides for very high deflection angles of pivotable yoke shaft (102) with respect to the rotation axis of rotating grooved disc (104). Generally, such deflection angles can easily exceed 30 degrees thus, allowing for a very wide range of RPM ratios and TORQUE amplification factors from a high end of over 90 to 1 to a low end of below 3 to 1. In one embodiment, two sets of the two freewheel double yoke assemblies can be co-axially but not co-rotatably placed each on either side of a double faced main output gear such that the central cross assembly freewheels of the right set are positioned on the "north-south" axis when viewed from the front and the central cross assembly freewheels of the left set are positioned on the "east-west" axis, respectively, thus being 90 degrees out of phase with each other. This arrangement offers the same output gear rotation smoothness as a single four freewheel double yoke assembly but without the use of the oscillating horse shoe.
Referring to FIG. (18), two sets of the four freewheel double yoke assembly are coaxially but not co-rotatably placed each on either side of double faced main output gear (137) such that the central cross assembly "north-south" freewheels (116) and (117) of the right set are positioned on the north-south "0-180" degree axis when viewed from the front and the central cross assembly "north- south" freewheels (138) and (139) of the left set are positioned on the northeast-southwest "45-225" degree axis of the embodiment when viewed from the front, thus being 45 degrees out of phase with each other. The left four freewheel double yoke assembly consists of four freewheels (138), (139-not shown), (140) and (141 - not shown), a common output shaft (143) with its reduction gear (142), a common input shaft (144), a pivotable yoke (145), a grooved disc (146) and a fixed yoke (147) in mirror image of the right four freewheel double yoke assembly. Pivotable yokes (102) and (145) deflect outwards within their corresponding grooved disc straight bogie tracks in absolute unison and in a diametrically opposed fashion in order to enhance balancing generally. This arrangement offers an extremely smooth output gear rotation down to an input shaft rotation of well below 500 RPM.
Arrangements using more than two sets of double yoke embodiments (each equipped with two or four freewheels) engaging one or more main output gears can be utilized to meet any extraordinary or special application requirements.
For a given input shaft RPM and TORQUE setting, and regardless of the configuration employed (two, four or six freewheel swash plates or two or four freewheel double yoke embodiments or multiple sets thereof), every specific pivot angle setting (for swash plate embodiments) and every specific shaft deflection angle setting (for double yoke embodiments) will result in one and only one output TORQUE and RPM setting provided that all of the freewheels have identical perimeters (teeth) to each other, are engaged to one or more main output gears having identical perimeters (teeth) to each other and that all pivot/deflection angles of the swash/plates double yokes involved (if more than one) are identical.
For example, given a two freewheel swash plate or a two freewheel double yoke embodiment (where each freewheel is 180 degrees out of phase to the other) set at a pivot/deflection angle of (1) degree with respect to the input shaft/grooved disc shaft: for every (360) degrees of rotation of the input shaft/grooved disc each freewheel's main concentric shaft will oscillate through a total of (4) degrees and will cause its respective freewheel to provide 2 degrees of positive engagement to the main output gear (where the Freewheel will cause the main output gear to rotate) and 2 degrees of disengagement (where the main output gear will cause the freewheel to rotate) since each freewheel carrying main shaft will oscillate from (-1) degree through (0) degrees to (+1) degree for the first 180 degrees of rotation of the input shaft/grooved disc and then from (+1) degree back through (0) degrees to (-1) degree for the second 180 degrees of rotation of the input shaft/grooved disc. Thus, for (1) degree of pivot/deflection each freewheel will positively engage the main output gear through (2) degrees and disengage for another (2) degrees (since both freewheels continuously and directly mesh with the main output gear but are opposite each other) thus in fact rotating (4) degrees around its main concentric shaft for every 360 degrees of rotation of the input shaft/grooved disc. This effectively provides a ratio of input shaft/grooved disc RPM to freewheel RPM of (360) degrees to (4) degrees or (90 to 1) and a multiplication of freewheel TORQUE with respect to input shaft/grooved disc TORQUE by a factor of (90).
Correspondingly: (2) degrees of pivot/deflection angle will provide input shaft/grooved disc to output shaft RPM ratios of (45 to 1) and a multiplication of freewheel TORQUE with respect to input shaft/grooved disc TORQUE by a factor of (45), and (22.5) degrees of pivot/deflection angle will provide input shaft/grooved disc to output shaft RPM ratios of (4 to 1) and a multiplication of freewheel TORQUE with respect to input shaft/grooved disc TORQUE by a factor of (4).
TABLE A
pivot angle or deflection angle
RPM ratio of in shaft/Disc to freewheel
Torque increase factor
pivot angle or deflection angle
RPM ratio of in shaft/Disc to freewheel
Torque increase factor
1
90.00 to 1
9.00
16
5.63 to 1
5.63
2
45.00 to 1
45.00
17
5.29 to 1
5.29
3
30.00 to 1
30.00
18
5.00 to 1
5.00
4
22.50 to 1
22.50
19
4.74 to 1
4.74
5
18.00 to 1
18.00
20
4.50 to 1
4.50
6
15.00 to 1
15.00
21
4.29 to 1
4.29
7
12.86 to 1
12.86
22
4.09 to 1
4.09
8
11.25 to 1
11.25
23
3.91 to 1
3.91
9
10.00 to 1
10.00
24
3.75 to 1
3.75
10
9.00 to 1
9.00
25
3.60 to 1
3.60
11
8.18 to 1
8.18
26
3.46 to 1
3.46
12
7.50 to 1
7.50
27
3.33 to 1
3.33
13
6.92 to 1
6.92
28
3.21 to 1
3.21
14
6.43 to 1
6.43
29
3.10 to 1
3.10
15
6.00 to 1
6.00
30
3.00 to 1
3.00
The invention's effect on RPM ratios and TORQUE amplification factors between the input shaft/grooved disc and the freewheels is summarized in Table A below:
At swash plate pivot angles or double yoke deflection angles below 1/2 of one degree the freewheels begin to cease positively engaging the main output gear and, thus, even though the input shaft/grooved disc continues to rotate the freewheels will effectively stop rotating and the main output gear to which they are engaged will also stop rotating. In effect all transmission of the input shaft/grooved disc rotation ceases and the swash plate/double yoke embodiments act like an input source RPM disengaging clutch.
Once the pivot/deflection angle starts positively engaging the freewheels at say 1/2 of one degree the invented transmission's freewheels provide their highest TORQUE amplification of the input source TORQUE and correspondingly their lowest output RPM with respect to the input source RPM.
Furthermore, in configurations employing multiple pairs of freewheels engaged to the same main output gear (but out of phase to each other), each freewheel positively engages the main output gear only when the main concentric shaft to which it is mounted oscillates in such positive direction faster than any other main concentric freewheel shaft at that given time and disengage its main concentric shaft at all other times.
supportive
Thus all additional freewheels (over and above the basic two opposed freewheels of any embodiment) provide a effect to one another and not a cumulative effect.
Thus in the case of a single "four freewheel swash plate/double yoke embodiment," each freewheel will positively engage the main output gear through only 90 degrees before its neighboring freewheel begins to engage the main output gear due to the faster rate of rotation of its concentric main carrying shaft.
Correspondingly, in an embodiment involving two "four freewheel awash plate/double yoke embodiments" engaged to the left and right of a double faced (toothed) main output gear and 45 degrees out of phase to each other, each of the eight freewheels will engage the main output gear through only 45 degrees before its neighboring freewheel begins to engage the main output gear due to the faster rate of rotation of its concentric main carrying shaft. This will result in a perfectly smooth and fluent rotation speed of the main output gear at 500 input shaft RPM or even lower.
Since the angle of pivot/deflection of the swash plate/double yoke embodiment can be varied infinitely within the range between 0 degrees and over 30 degrees so too will the transmission's RPM ratios and TORQUE amplification factors vary infinitely within the range of over 90 to 1 down to below 3 to 1.
Furthermore, the transmission system of the present invention remains continuously engaged throughout the entire shifting process. This means that since there are no neutral spots in the shifting process (excepting only when the transmission acts like a clutch at the (0) degree pivot/deflection angle setting) there can be no loss of momentum whatsoever while upshifting or downshifting.
In conclusion, the invention provides for an infinitely and continuously variable transmission system which is very compact, has very few and simple-to-engineer moving parts, has very low friction losses with correspondingly low wear and tear, requires no input shaft disengaging clutch, provides infinite TORQUE and RPM ratios within a range starting from over (90 to 1) down to below (3 to 1) while at the same time it is able to deliver very high TORQUE throughputs without any slippage whatsoever.
The preferred embodiments of the present invention having been described, it will be appreciated by those of ordinary skill in the art that there can be departure from the details set forth herein without departing from the true nature and scope of the invention. | |
OK, some kids out there have been making a lot of snow ghost pies, because this winter thing is not slowing down! As we head into snow day #2 of the week, I feel it necessary to post one more cozy breakfast food, just because. Yes, this has been a very carb-heavy spell on Bring It, and I promise, the green is coming. But for now we still need some comfort food to get us over the snowbank and into spring.
So, voila! Here is another episode of overnight breakfast brilliance (with a fancy French name at no extra charge.) This came from Gourmet circa 2003. Imagine yourself at a friend’s house for a weekend. Big dinner Saturday night. As you are cleaning up afterwards, finishing a glass of wine, take one of the dishes you have just washed and instead of putting it away, butter it (with the nice soft butter that’s lying around), lay the uneaten baguette slices in it, and whip up the super easy custard to pour over it. Then stash the whole thing in the fridge. Nobody even noticed what you were doing and the next morning, Ta da! Pain perdu. AKA baked French toast for those of us on this side of the pond.
If you are not at a friend’s house having a big dinner party you can still whip this up and be a hero in your own home. Use whatever bread you have (you know, love the one you’re with), and don’t be afraid to use the rest of that Maple Oat Breakfast Bread for a double shot of maple.
Pain Perdu
Ingredients
1 – 13 to 14 inch long loaf of soft-crust supermarket Italian bread (without seeds)
1/2 stick (1/4 cup) softened unsalted butter
2 large eggs
1 2/3 cups whole milk
1/4 tsp salt
3 Tbsp sugar
Handful of chopped walnuts or pecans (optional)
Method
Cut 12 1-inch thick diagonal slices from bread (don’t use ends).
Butter 1 side of each slice and arrange slices, buttered sides up, in 1 layer in a buttered 13 by 9 inch glass baking dish, squeezing them in slightly to fit.
Whisk together eggs, milk and 1/4 tsp. salt until combined well, then pour evenly over bread.
Chill, covered until bread has absorbed all of custard – at least one hour and up to 1 day, depending on bread.
In the morning: Take pan out of the refrigerator to bring to room temperature and preheat oven to 425 degrees.
Sprinkle bread with 3 tablespoons of sugar. Sprinkle on chopped nuts, if using.
Bake, uncovered in middle of oven until bread is puffed, and top is golden – about 20 to 25 minutes. Serve immediately with topping and syrup of choice (as long as it involves real maple). | https://bringiteats.com/pain-perdu-ooh-la-la/ |
Time needed: 40–50 minutes
Materials needed:
Setup:
Birds can be identified by their shape, their color, their sound, and what they’re doing. You can find birds in your neighborhood, in the woods, or at the zoo. You can even watch birds in nature through videos and livestreams.
Bird scientists are called ornithologists. They gather all kinds of data or information about birds. They write down the kinds of birds they see. They write down how many they see. They write down what the birds eat. Bird-watchers keep lists of birds, too. Many people share their data with others. They might give a presentation or make a poster about what they’ve learned.
Just like scientists, you can track and share your data with others. One way to do this is with a data table. A data table is a chart. It lists information in rows and columns. Rows are lines that go from side to side. Columns are lines that go up and down. You can use a data table to track the kinds of birds you see. You can also make tally marks to count how many you see. You can count or add your tally marks to find out how many birds you saw of each kind and in total.
Activity:
First, decide how you’ll go bird-watching. Go outside or have an adult help you find nature videos or livestreams with birds online. Then, look at the field guides or have an adult help you research online to learn about the birds you expect to see. Find information about their names, shapes, colors, and songs or calls. If you can, find audio for the birds’ calls, too.
Next, set up a data table. Make a grid with three rows and at least five columns. In the boxes of the first column, going from top to bottom, write, “Kind of Bird,” “Tally,” and “Total.”
Then, go bird-watching. If you see a bird, try to identify it. Add each new kind of bird you see to the top row of a column. If you don’t know, that’s okay—just write or draw what it looks like. Add more columns if needed.
Track the number of birds you see in the row below with tally marks. For example, if you see three cardinals, write “Cardinal” on top of a column and make three tally marks in the row below. Be very quiet so you don’t miss any birds. Sometimes you’ll hear a bird before you see it. Look and listen very closely.
Afterward, organize your data. Try to identify any birds you didn’t know earlier. Find the total for each kind of bird by counting the tally marks in each column. Write the total number for each kind of bird in the row below the tally marks. If needed, write an equation, like 5 + 5 + 5 + 5 + 3 = 23. Then, find the total number of birds you saw. Use an equation to add the row of numbers you just wrote, or count all the tally marks in the row above.
Look at your final data table: how many birds did you see of each kind? How many did you see in total? What kind of bird did you see most often? Which kind did you see the least often? Lastly, brainstorm how the bird count would change if the season or location were different. How do your location and the weather affect the kinds of birds you see?
If you can, show your data table to someone else. Tell them about the birds you saw. What was your favorite part about bird-watching? What can you learn from watching birds? Would you like to go bird-watching again?
Download the Badge Requirements.
Troop Leaders: The instructions for all badge steps
are available free of charge in the Girl Scout Volunteer Toolkit.
Girl Scout Activity Zone activities have been adapted from existing Girl Scout programming. | https://www.girlscouts.org/en/activities-for-girls/brownies/brownie-create-data-table-badge-activity.html |
Happy November! We've had a huge cool down in the weather in the last few days, and it is totally getting me in the mood for fall (and especially yummy fall foods). I loooove soups and could eat them for dinner every night in the fall, and these flaky buttermilk biscuits are pretty much the best ever side for soup. I've made them more times than I can count now, and every time they disappear within a few minutes. The kids love them, and we're pretty obsessed with them too! I served these with some butternut squash soup (recipe coming soon) and fresh homemade peach jam. They are pretty much just biscuit perfection!
Flaky Buttermilk Biscuits
2 cups flour
1 tablespoon sugar
1 tablespoon baking powder
1 teaspoon salt
1/2 cup butter, cut into pieces
3/4 cup buttermilk
Preheat the oven to 450. Line a baking sheet with parchment or spray with cooking spray. In a large bowl, whisk together the flour, sugar, baking powder, and salt. Add the butter and cut in using a pastry cutter or two knives, until the butter is about pea-sized and smaller. Add the buttermilk and mix until just combined. Turn the dough out onto a lightly floured surface and pat into a rectangle that is about 6 x 9 inches. Fold each side of the dough over the middle (like you're folding a letter) and pat out again to about 6 x 9 inches. Cut biscuits out of the dough using desired size of biscuit cutter (I usually use a 2 inch cutter). Place on prepared baking sheet and bake 10-12 minutes, or until golden brown. Serve warm and enjoy! | https://www.thebakerupstairs.com/2014/11/flaky-buttermilk-biscuits.html |
From My View For July 20
With the 71st Rudy Mumley OVAC All-Star Game coming Saturday evening, I can picture loads of things that will happen during all the festivities. I can’t wait to see it unfold. However, there are festivities that I haven’t had the pleasure of attending but have heard a lot about.
The first day, the players from both the Ohio and West Virginia All-Stars meet each other and their coaching staff at Bethany College. Getting to know guys you faced in the trenches, that will now be your
teammates, will be something to remember. The trading of T-shirts, helmet stickers, and the war stories that will be exchanged will be something to be around.
The coaches, who may or may not have seen some of their new all-stars play, will meet for the first time and will need to figure out in a very short time where each player can help the team. After a few months of not playing football, the players must get ready to run, tackle and block again. Some might have put on a few pounds and will need to dig deep to get ready.
When all the band and cheerleading all-stars show up, it is about the same. I can picture all of them hugging one another and telling stories about their adventures they had during school and band camps. It will be a great experience to play music with different musicians and work on footwork for the different shows they will show us on the field at halftime.
With the band, both the Ohio and West Virginia kids will be on the same team now, but I’m sure they will be rooting inside when the game starts. The cheerleaders, like the players and the band members, will meet their teammates for the first time and share the things that cheerleaders share. The camaraderie of cheerleading is awesome. Not only do they have to be pleasant when they’re sad, they must learn different formations, dance routines and cheers.
The players, coaches, Queen of Queens candidates and all-star cheerleaders came together for the first time at the annual George Strager Evening With the Stars. Dinner is held at the White Palace at Wheeling Park.
This is a great experience for the kids in more ways than just football and making friendships with each other. Many don’t have no idea who George Strager or Rudy Mumley are, so it’s a great learning process for these guys to know how this whole week came to be. And that will only continue as days and nights go by.
There are activities for the kids each day, including an ice-cream social and a Queen of Queens pageant where 21 high school pageant winners will perform at the historic Capital Music Hall in downtown Wheeling.
The OVAC McDonald’s All-Star Band will first show off its routine at a pep rally on the Bethany College campus. The players, cheerleaders, queens and coaches will then attend a dance. The Osiris Shrine guys have a Film and Pizza Night at the Steinman Theater for all the kids at Bethany College too.
Besides all of this, there will be a reunion luncheon for the 1966 former all-stars. The tales, I’m sure, will be plentiful.
Then it will be time for the game. This year, the game will be played on Saturday, instead of Sunday, and its Pack The House Night on Wheeling Island Stadium.
The hard work that the OVAC Rudy Mumley All-Star Committee and staff will start to take form. To put an All-Star fun-filled week for the kids in the OVAC, and to even give scholarships to boot, my hat is off to the OVAC.
I know, I probably missed some of the festivities, but like I said these are the things that the OVAC does for our kids that I know have, but not had the pleasure of attend.
I hope and pray, that this year’s All-Star Classic goes on without a hitch, and people off all ages can go and watch a bunch of our area youths have the time of their lives and build friendships they would have ever had if there wasn’t an Rudy Mumley All-Star Classic. | https://www.wetzelchronicle.com/sports/local-sports/2016/07/20/from-my-view-for-july-20/ |
The number of people that could be sent to another planet would be rather limited, says Jean-Marc Salotti at the Bordeaux Institut National Polytechnique, the author of “The Minimum Number of Settlers for Survival on Another Planet.”
“A mathematical model can be used to determine the minimum number of settlers and the way of life for survival on another planet,” writes Salotti. “The minimum number of settlers has been calculated and the result is 110 individuals.”
That figure is interesting. SpaceX is currently working on its Starship, something of a reusable interplanetary spaceship that would be capable of sending 100 passengers at a time to Mars. However, Salotti has doubts about reusability and thinks that developing a vehicle that can both land and relaunch from Mars could take several decades.
Developing a vehicle that can both land and relaunch from Mars could take several decades to ... [+] perfect.
Getty
Concepts of crewed Mars missions take about six months for between three and six astronauts to reach the planet, along with a few dozens of tons of consumables. Although it may be possible for some resources to be obtained from Mars—carbon dioxide from the atmosphere, water ice from the soil to produce oxygen and organic compounds, hematite to produce iron, silicates to produce glass—we’re decades away from understanding if any of that would be practically possible.
Salotti’s calculations are based on the ability of a group of individuals to survive if cargo drops from Earth were stopped. That could perhaps be because a colony is becoming too expensive to send cargo to, because of war on Earth, or because the colonists decide to go it alone and declare an independent Martian republic.
It takes into account factors like how long the colonists would need to to spend mining, producing metal, ceramics and glass, chemicals and clothes, and recommends that colonists use three guiding principles:
Make it simple: minimize the need for complex objects. All individuals to live under a dome (covered in a few meters of soil to protect the colonists from radiation) and share the same life support system. Plants will be grown in greenhouses, water will be extracted from ice, solar panels use for electricity and methane used to power engines. Salotti thinks that producing new solar panels and new spacesuits would be a major challenge for the colonists that they would need to overcome.
I'm an experienced science, technology and travel journalist interested in space exploration, moon-gazing, exploring the night sky, solar and lunar eclipses, astro-travel, wildlife conservation and nature. I'm the editor of WhenIsTheNextEclipse.com and the author of "A Stargazing Program for Beginners: A Pocket Field Guide" (Springer, 2015), as well as many eclipse-chasing guides. | |
The main aim of this paper is to appreciate and evaluate human resource management practice of nurse managers utilizing Henri Fayol’s theory. The study being conducted to health facilities in Southern Leyte purposively employed sixteen respondents qualified based on the inclusion criteria such as having supervisory experience of atleast five years, either male or female and with permanent employment status. The study utilized descriptive-evaluative research design in order to collect information without manipulating or changing study subjects and its environment. Demogrpahic data were tabulated using simple percentage. Weighted mean was also used to establish different management practice delivered and implemented by nurse managers. Based from the findings, most of the nurse managers are female (87%), aging 40-47 years old, with an average gross individual monthly income of 17,000 to 25,000 thousand pesos. All of them did not have units of graduate degrees, however underwent trainings parallel to nursing practice. Education and supervisory-related trainings were acquired through shadowing and peer-coaching. Nurse Managers identified that the fast turnover of staff nurses is the leading factor affecting human resource management due to low salary rate of staff nurses. On the other hand, planning and controlling were the least among the five managerial roles delivered by nurse managers. The study recommends enhancement of these management components to effectively deliver care among clientele.
American Nurses Association. Standards and Practice of Nursing. 2012.
Masters K. Role Development in Professional Nursing Practice. Jones & Bartlett Publishers; 2015. 474 p.
Sullivan EJ, Decker PJ. Effective Leadership and Management in Nursing. Pearson/Prentice Hall; 2005. 372 p.
Wilson BL, Butler MJ, Butler RJ, Johnson WG. Nursing Gender Pay Differentials in the New Millennium: Gender Pay Differentials. J Nurs Scholarsh. 2018 Jan;50(1):102–8.
Dehghani K, Nasiriani K, Salimi T. Requirements for nurse supervisor training: A qualitative content analysis. Iran J Nurs Midwifery Res. 2016 Feb;21(1):63.
Brown P, Fraser K, Wong CA, Muise M, Cummings G. Factors influencing intentions to stay and retention of nurse managers: a systematic review. J Nurs Manag. 2013 Apr 1;21(3):459–72.
Clark L. Leading by example. Nurse Manag. 2008;15(6):12–5. | http://jurnalfpk.uinsby.ac.id/index.php/jhsp/article/view/120 |
Synopsis: The Opposite of Friction
The motion of paired particles (dimers) on a surface appears in a wide variety of different contexts, such as the layer-by-layer growth of a semiconductor or the hopping of molecules in an optical lattice. In Physical Review E, David Speer at Bielefeld University, Germany, and colleagues report a nonintuitive effect based on their calculations of the motion of a dimer of two identical particles on an isotropic surface: in spite of the intrinsic symmetry of the system, a periodic external potential acting on the dimer can cause a spontaneous symmetry breaking. This is reflected in the net motion of the dimer in a specific direction, which depends on the initial conditions. The essential condition for this effect is a non-convex interaction potential between the dimer components, such as one where the potential changes from repulsive to attractive with distance.
Speer et al. show that if a dimer is also subjected to thermal noise, it can exhibit a divergent diffusion constant at low temperatures – a counterintuitive result, given that the diffusion coefficient of a particle on a surface usually vanishes as the temperature goes to zero. Furthermore, under the action of a constant force, the dimer can have a “negative mobility,” where it moves in the opposite direction to that of the applied force. According to the authors, this behavior could be observed in a nanofriction experiment, where the friction force may be acting not against, but along the pulling direction – a phenomenon bearing some resemblance to so-called superlubricity. – Hernan Rozenfeld
Dimer motion on a periodic substrate: Spontaneous symmetry breaking and absolute negative mobility
David Speer, Ralf Eichhorn, Mykhaylo Evstigneev, and Peter Reimann
Phys. Rev. E 85, 061132 (2012)
Published June 28, 2012
Features
Meetings: An Astronaut’s View of Thunderstorms
Videos of thunderstorms recorded from space reveal unexpectedly active lightning in the sky above storm clouds.
Q&A: A World of Experiments Inside a Liquid Crystal
Teresa Lopez-Leon describes how topological defects in liquid crystals could be used to create artificial atoms or to study math problems in the lab.
Highlights of the Year
Physics looks back at its favorite stories from 2016.
Announcements
Topological Phases
Find out more about topological phases of matter in this collection of articles from the archive of Physics. | http://physics.aps.org/synopsis-for/10.1103/PhysRevE.85.061132 |
China’s Long March 3C opens record-setting Year with Beidou Navigation Satellite Launch
China’s year opening space launch took place on Monday from the Xichang Satellite Launch Center when a heavy-lift Long March 3C rocket blasted off on a multi-hour mission to deliver the next Beidou-3 navigation satellite to orbit to become part of the Chinese pendant to the American Global Positioning System or Europe’s Galileo Satellite Navigation System.
Liftoff occurred just after 7:30 UTC Monday morning, according to local reports of shaking windows and photos posted to Chinese social media. Confirmation of launch success will be provided after the successful insertion into an orbit over 20,000 Kilometers in altitude, several hours after liftoff.
Monday’s mission – opening what is expected to be a record-setting year for Chinese space flight – marks the last launch of an experimental Beidou-3 navigation satellite in an important step in Phase III of the Beidou program, scheduled for completion by 2020 for operational global navigation coverage. Over two dozen launches from Chinese launch centers are on the books for 2016 including the first missions from the Wenchang Satellite Launch Center, premiering the Long March 5 and Long March 7 launch vehicles. China also plans to launch the Tiangong-2 Space Station module later this year to be followed up with a crewed mission using the Shenzhou spacecraft to visit the miniature space station in China’s continued development efforts aiming to deploy a modular station around the end of the decade.
Beidou-3 is the third phase in China’s Navigation Satellite System that finds its origin in 1983 when the first concepts were submitted. The project had a long road to orbit, seeing its first launch in 2000 when the first generation of Experimental Satellites began deployment to Geostationary Orbit. Consisting of only three Geostationary Satellites, the system offered navigation services for just the Chinese territory, reaching an accuracy of 20 meters. To expand navigation services to the broader Asia-Pacific region, the Beidou-2 series was inaugurated in 2009 comprised of five satellites in Geostationary Orbit, five in inclined Geosynchronous Orbits and four (plus one test satellite) in Medium Earth Orbit. The second phase of the program saw an increase in accuracy and a longer in-orbit life of the satellites.
This step-wise deployment of navigation satellites allowed lessons to be learned and implemented before the final stage of the project – the establishment of a Global Navigation Satellite System combining a number of satellites operating from different orbits. The Beidou-3 satellite constellation will consist of 27 Beidou-3M satellites in Medium Earth Orbit, each weighing 1,014 Kilograms, five 4,600-Kilogram Beidou-3G satellites in Geostationary Orbit and three Beidou-3I satellites in inclined Geosynchronous Orbits each with a mass of 4,200 Kilograms.
To provide compatibility with receivers built for the first and second generation of Beidou, the Geostationary and Geosynchronous satellites of Beidou-3 carry two navigation payloads – the Radio Determination Satellite Service that provides compatibility with Beidou-1 terminals, and the Radio Navigation Satellite Service operating like the Global Positioning System.
The Radio Determination Satellite Service uses two GEO/GSO satellites that are contacted by the terminal on the ground. Time delay data recorded for signals from both satellites is then sent to a ground station that employs a topographic algorithm to turn the 2D measurement made by two satellites into a 3D position that can be sent back to the user.
The Radio Navigation Satellite Service operates in a similar way as the Galileo, GPS, Glonass and IRNSS navigation systems – sending coded signals in the L-Band frequency with ultra high timing precision so that receivers on the ground can process three or four different signals in order to calculate the user’s precise position, elevation and speed.
The Medium Earth Orbit Satellites carry only the Radio Navigation Satellite Service payload allowing them to be smaller in size. They weigh 1,014 Kilograms and are based on a newly developed satellite bus smaller than the DFH-3 platform, but using a number of DFH-3 heritage components to match its capabilities and reduce risk. The three-axis stabilized satellites accommodate a payload mass of 280 Kilograms and measure 2.25 by 1.0 by 1.22 meters in size. Two deployable solar arrays generate 1,500 Watts of of power.
The Medium Earth Orbit satellites are deployed to an orbit of 21,500 Kilometers inclined 55 degrees and the finished constellation will feature three orbital planes with nine satellites per plane to guarantee global coverage.
>>Beidou-3 Satellite Constellation Overview
Monday’s mission is the third flight of China’s YZ-1 restart-capable upper stage.
To loft the Satellites directly into or close to their operational orbit, China developed a multi-purpose upper stage that can perform multiple engine burns over missions of several hours to deliver payloads to a variety of orbits. The Yuanzheng-1 (Expedition-1) upper stage is equipped with its own power, navigation, control and propulsion systems to autonomously perform missions with several burns spaced by extended coast phases.
Using storable propellants, the main engine of the YZ-1 stage delivers 6.5 Kilonewtons of thrust. At least two burns can be supported by the stage. The first to enter an elliptical transfer orbit, the second to circularize the orbit at the desired altitude. The capabilities of this new upper stage can be compared to Russia’s Fregat stage used aboard the Soyuz rocket when delivering payloads to high-energy orbits.
Lifting off from Xichang at around 07:30 UTC on Monday, the 56.3-meter tall Long March 3C Rocket, weighing 368 metric tons, began heading south-east after a short vertical ascent. Under the power of its core stage and two liquid-fueled boosters, the vehicle began racing downrange for a trip over China before heading out over the Pacific Ocean, starting with a total thrust of 458 metric-ton-force.
The twin boosters, each 16.09 meters long and 2.25 meters in diameter holding 41,100 Kilograms of storable propellants, were to burn for two minutes and 20 seconds to deliver 740 Kilonewtons of thrust for the initial flight portion. The vehicle was to continue powered flight on the four-chamber DaFY-6-2 engine of the core stage delivering 2,961 Kilonewtons of thrust. Over a burn of 158 seconds, the 24.76-meter long first stage was to burn through 186,200 Kilograms of hypergolic propellants.
>>Long March 3C Technical Overview
Separation between the first and second stage was planned to occur in hot mode with the vernier engine of the second stage igniting to pull the 12.92-meter second stage away from the spent core upon separation. Igniting its 742-Kilonewton main engine, the second stage was to burn 49,000 Kilograms of propellants for a burn of close to three minutes.
Assuming control of powered flight, the cryogenic third stage, consuming LOX and LH2 propellants, was expected to ignite the YF-75 dual-engine cluster to deliver 16,000 Kilogram-force of thrust to boost the stack into an elliptical orbit.
Immediately after separation from the launch vehicle, the YZ-1 upper stage was to start an engine burn to deliver the stack to an elliptical transfer orbit with an apogee on the order of 22,000 Kilometers. Next was a long coast phase of around three and a half hours to allow the stack to climb up to a position near apogee so that the second burn of the upper stage could serve as a circularization maneuver to reach a circular orbit just over 22,000 Kilometers in altitude, at an inclination of 55 degrees. | https://spaceflight101.com/chinas-long-march-3c-opens-record-setting-year-with-beidou-navigation-satellite-launch/ |
Joint plate in high quality developed for the chemical industry: composed of aramidics fibers, fillers and a mixture of heat-resistant CSM particularly suitable for acid and alkaline levels and chemically aggressive fluids in general.
Applications
Acids, alkalis, solvents, chemical, petrochemical and pharmaceutical industries.
DIN3754
1,75
Max. work range temperature
250°C
Max. work range pressure
60 bar
Compressibility
ASTM F36
8%
Elasticity
ASTM F36
45%
Stress retention 16 hours – 175°C. 50 N/mm2
DIN 52913
25 N/mm2
Tensile strenght (min.)
DIN 52910
8 N/mm2
Permeability to nitrogen
DIN 3535/4
0.6ml/min
Loss on ignition
DIN 52911
30%
Diving behavior ASTM F146 – in oil ASTM n°3 for 5 hours at 150°C
Thickness increase in nitric acid
max.
10%
Thickness increase in sulfuric acid
max.
10%
Tensile stranght in sulfuric acid
min.
6 N/mm2
Constant clamping ASME – VSR
Thickness > 1,5 mm.
3,0 mm.
Y
25 Mpa
11 Mpa
M
2,75 Mpa
2,00 Mpa
*The data listed depend on a variety of factors (state of the joints, dimensions, clamping, thermal and mechanical shock etc.) To which can be indicated for orientation purpose. | https://www.gasketitaly.com/en/products/splice-type-met-acid/ |
Structural studies of the lipid components of bile.
The lipid-rich molecular aggregates responsible for the transport of cholesterol in bile include mixed micelles and bilayer vesicles. In this review, the molecular conformations of the individual lipid components of biliary micelles and vesicles (phospholipids, bile salts and cholesterol) obtained by high-resolution x-ray crystallographical analysis are described. The key conformational/packing features relevant to lipid organization, molecular interactions and cholesterol solubility in bile are discussed. The structure of cholesterol monohydrate, the major component in cholesterol gallstones, is described and problems relevant to cholesterol crystal nucleation/growth processes are briefly discussed.
| |
Gain/loss, status/disgrace, censure/praise, pleasure/pain: these conditions among human beings are inconstant, impermanent, subject to change. Knowing this, the wise person, mindful, ponders these changing conditions. Desirable things don’t charm the mind, undesirable ones bring no resistance. His [or her] welcoming and rebelling are scattered, gone to their end, do not exist. Knowing the dustless, sorrowless state, he [or she] discerns rightly, has gone, beyond becoming, to the Further Shore.
AN 8.6 Lokavipatti Sutta: The Failings of the World
Having just landed back in the Blue Mountains, Australia, after two months of travel in the Northern Hemisphere and New Zealand, there’s now some time to catch my breath and reflect on the kaleidoscope of people and places I’ve just visited. Perhaps because conditions were changing so rapidly, it was so clear that whenever there was holding on, there was suffering. And when there was no holding on, no resistance, there was no suffering. Moving through – or with – all of these changes, I’m grateful for the possibility of equanimity; and grateful too, for the rich experiences of these last few weeks.
And to finish, some more thoughts on equanimity from Pema Chodron:
To cultivate equanimity we practice catching ourselves when we feel attraction or aversion, before it hardens into grasping or negativity. We train in staying with the soft spot and use our biases as stepping-stones for connecting with the confusion of others. Strong emotions are useful in this regard. Whatever arises, no matter how bad it feels, can be used to extend our kinship to others who suffer the same kind of aggression or craving — who, just like us, get hooked by hope and fear. This is how we come to appreciate that everyone’s in the same boat. We all desperately need more insight into what leads to happiness and what leads to pain.
It’s easy to continue, even after years of practice, to harden into a position of anger and indignation. However, if we can contact the vulnerability and rawness of resentment or rage or whatever it is, a bigger perspective can emerge. In the moment that we choose to abide with the energy instead of acting it out and repressing it, we are training in equanimity, in thinking bigger than right and wrong. This is how all the four limitless qualities — love, compassion, joy, and equanimity — evolve from limited to limitless: we practice catching our mind hardening into fixed views and do our best to soften. Through softening, the barriers come down. | https://jill0shepherd-insightmeditation.com/tag/london/ |
The use of an electric vehicle (EV) over a gasoline vehicle (GV) is often portrayed as environment friendly or green movement ignoring how the electricity is produced. EVs get credit for preserving green environment and preventing global warming by minimizing the dependency on oil. Most of the time, these assumptions that favor EV are not well justified. Therefore, proper studies on the impact of electric vehicles on energy demand, on environment and on power system are necessary before reaching to any conclusion. This thesis explores the possibility of energy consumption pattern shift within the different sectors of energy use due to the massive switching of EVs over traditional GVs. In an attempt to find out whether electric vehicles are really efficient over traditional vehicles in terms of energy use as well as emissions, a complete well-to-wheel analysis and estimations of emissions during their use are calculated and compared. Lastly, a survey on the effect due to high penetration of electric vehicle chargers on the residential power grid is presented.
Tiwari, Sital, "Impact of plug-in electrical cars on energy demand, on power system and on environment" (2012). LSU Master's Theses. 2967. | https://digitalcommons.lsu.edu/gradschool_theses/2967/ |
Is qibla and Kaaba the same?
The qibla is the direction of the Kaaba, a cube-like building at the centre of the Sacred Mosque (al-Masjid al-Haram) in Mecca, in the Hejaz region of Saudi Arabia. The Kaaba has an approximately rectangular ground plan with its four corners pointing close to the four cardinal directions.
Do Muslims pray to the Kaaba stone?
Muslim pilgrims circle the Kaaba as a part of the tawaf ritual during the hajj and many try to stop to kiss the Black Stone, emulating the kiss that Islamic tradition records that it received from Muhammad. Muslims do not worship the Black Stone.
What Stone is in the Kaaba?
the Black Stone of Mecca
Located in the eastern corner of the Kaaba is the Black Stone of Mecca, whose now-broken pieces are surrounded by a ring of stone and held together by a heavy silver band. According to tradition, this stone was given to Adam on his expulsion from paradise in order to obtain forgiveness of his sins.
What is in Mecca stone?
Muslims say that the Stone was found by Abraham (Ibrahim) and his son Ishmael (Ismail) when they were searching for stones with which to build the Kaaba. It has been described variously as basalt stone, an agate, a piece of natural glass or — most popularly — a stony meteorite.
What is called the qibla?
Qiblah, also spelled qibla or kiblah, the direction of the sacred shrine of the Kaaba in Mecca, Saudi Arabia, toward which Muslims turn five times each day when performing the salat (daily ritual prayer). In a mosque the qiblah is indicated by the mihrab, a niche in the building’s interior wall facing Mecca.
Can Muslims go inside Kaaba?
Today, the Kaaba is kept closed during the hajj because of the overwhelming number of people, but those who visit the Kaaba during other times of the year are sometimes allowed to go inside. It’s quite beautiful: The walls are white marble on the lower half and green cloth on the upper half.
How does Qibla finder work?
Launched during Ramadan, Qibla Finder (g.co/QiblaFinder) uses augmented reality to show Muslims the fixed direction toward the Kaaba in the Grand Mosque in Mecca, Saudi Arabia. Just go to the address g.co/QiblaFinder on your smartphone and move the camera until the Kaaba symbol shows up, floating in space.
Is the qibla in the direction of the Kaaba?
A pilgrim makes a supplication in the direction of the Kaaba, the Muslim qibla, in the Sacred Mosque of Mecca. A prayer congregation in the United States prostrates in the same direction: the qibla.
Why do Muslims not worship the Kaaba and the Black Stone?
The Kaaba is to show the direction (qibla) for the 5 prayers (salat). Also, touching or kissing the Black Stone is to symbolically connect Muslims to divinity and the hereafter. So Muslims neither worship this cube structure in the desert nor the black stone that is stuck in its Eastern corner.
Is the Holy Kaaba the direction of prayers?
The Holy Kaaba; The Direction of Muslims’ Prayers. According to the Quran and the Bible, the Holy Kaaba is just a focal point for the Muslims all over the world. It is actually the direction given to the Muslims for offering prayers. Muslims from all over the world face to the direction of Kaaba in Makkah five times a day.
How is the Kaaba different from Hindu and Buddhist idols?
Difference Between the Holy Kaaba and Hindu or Buddhist Idols. Islam denies the idol-worship. On the other hand, it believes in the Oneness of God. It is a fact that the Muslims all over the world only face the Holy Kaaba during prayers, they do not worship it (God forbids) or regard it to be their God. | https://pvillage.org/archives/18337 |
- It's never too early to share how you feel about drugs and what your expectations are in terms of zero tolerance of drug use by your children. A study showed that 74% of 4th graders wished their parents would speak with them about drugs.
- Every family situation is different. Some children are experimenting with drugs as young as 8 and 9 years old. We suggest that a program of random drug testing is implemented by the age of 12.
- First of all, stay calm. You are in control and now have the proof that your child is using drugs. Our program manual teaches you how to respond to a positive test. We're with you every step of the way. Should your child need counseling or treatment, we have the resources to help you take the next steps.
- Some children may refuse to comply with taking a drug test. We address this issue in our program manual. As a last resort, we do offer parents a method to test their child without the child's knowledge.
- Each panel shows the positive or negative result for a particular drug or drug category. So you know at a glance which drug you have tested positive for if there is one red line on the test strip.
- Be on the look out for warning signs such as:
- Skipping school, a drop in grades, and changes in friends
- Changes in appearance, mood, behavior, or motivation
- Missing money, valuables, liquor or beer
- Discovery of smoking paraphernalia (e.g., pipes, papers, small containers, baggies, or short sections of drinking straws)
- Frequent unexplained colds, nausea, or watery or red eyes
- In addition to several of the warning signs of abuse listed for Teens, be observant of the following signs: | https://www.catchthemquick.com/frequently-asked-questions/drug-questions-substance-abuse/ |
Ottawa – On Wednesday, September 19, 2012, The Honourable Jason Kenney, Minister of Citizenship, Immigration and Multiculturalism distributed a statement titled “MP Albrecht Expresses Canada’s Concern About the Release of Ramil Safarov”. This statement drew attention to a statement made that day in the House of Commons by Mr. Harold Albrecht, MP for Kitchener-Conestoga and President of the Canada Armenia Parliamentary Friendship Group on behalf of the Government of Canada. The statement, reproduced in full below, expresses the government’s “utter contempt and complete disbelief” at the pardon and release of convicted axe murderer Ramil Safarov by Azerbaijani authorities. The statement also expresses Canada’s continued support for the peace process in Nagorno-Karabakh.
This statement is only one of a number recent expressions of interest shown by the Canadian government and politicians in advancing the Nagorno-Karabakh peace process.
The Honourable Jim Karygiannis, MP for Scarborough-Agincourt acted as an official observer for the presidential election in the Nagorno-Karabakh Republic and held a town hall in Toronto on September 23, 2012, along with Mr. Robert Avetisyan, Permanent Representative of the Nagorno-Karabakh Republic to the United States of America and Canada, to deliver his verdict that the presidential elections were free of any irregularities and properly reflected the will of the people of the Nagorno-Karabakh Republic. Mr. Karygiannis also expressed his support for the recognition of the Nagorno-Karabakh Republic’s independence by the international community.
Additionally, Mr. Avetisyan recently held a meeting with Canadian parliamentarians in Ottawa where he discussed the ongoing peace process and explained the importance of Canada supporting international recognition of an independent Nagorno-Karabakh Republic.Text of a statement circulated by the Honourable Jason Kenney:
Friends,
I wanted to share this important statement made by MP Harold Albrecht on behalf of our Conservative Government in the House of Commons concerning the release of Ramil Safarov.
Harold Albrecht, Member for Kitchener—Conestoga (CPC): Mr. Speaker,
I rise today to express my utter contempt and complete disbelief of recent developments in the case of Azerbaijani military officer, Ramil Safarov.
On August 31, Safarov was transferred from Hungary to Azerbaijan to ostensibly serve out a life prison sentence for the brutal murder of an Armenian military officer in 2004. Upon his return, he was pardoned and released.
These developments are of real concern to Canada, and in particular to Canadians of Armenian descent who want peace in their homeland.
Murder should be condemned, not rewarded.
Canada continues to support the ongoing peace process, and we will continue to promote regional cooperation and reconciliation. We encourage all parties to take the necessary measures to increase trust and constructively contribute to the peace process between Armenia and Azerbaijan.
Sincerely, | https://www.anccanada.org/canada-expresses-renewed-interest-in-nagorno-karabakh-peace-process/ |
WHEN we think of medical advances, we think of a lonely scientist and an isolated eureka moment. One of them happened in 1928, when Alexander Fleming noticed that some mold accidentally found growing on a culture dish seemed to keep bacteria at bay. But only in 1945, after numerous others in academia and industry had worked to isolate, manufacture, and deliver penicillin, did the wonder drug begin to save lives and change the world.
Medical innovation has always depended upon the work of many people with many eureka moments. The dramatic medical advances of the last 30 years are the result of massive coordinated research efforts wholly unlike Fleming's haphazard accident.
Medical research today is a communal enterprise unfolding within a grand network. As Massachusetts seeks to nourish the local biotech industry, policy makers need to keep the collaborative nature of the industry in mind.
The economics of the enterprise rely on steady advances in science through a long pipeline. Basic discoveries, often made in university research laboratories and funded with government dollars from the National Institutes of Health or National Science Foundation, don't languish anymore; biotechnology, pharmaceutical, and medical device companies seize upon them eagerly.
Within this information-intensive network, biotechnology companies are the crucial connectors -- the drivers of medical innovation and the translators of theoretical breakthroughs into practical benefits for society.
In the 1980s, "biotechnology" typically referred to companies involved in recombinant DNA-based drug research. Today the term is more broadly defined around companies developing innovations across the biological and medical fields. Biotech healthcare companies work on injectable protein drugs, diagnostics, medical devices, vaccines, and pills.
The collaborative nature of the industry is particularly beneficial to Massachusetts, which is arguably the world center of life-science research today. The state is awash in great universities that justifiably attract a disproportionate share of NIH dollars and Nobel prizes. Surrounding these institutions are premier medical schools and hospitals that bring innovations to patients. This network has given rise to one of the largest, densest clusters of innovative biotechnology companies on the planet, with tens of thousands of jobs in a rapidly growing and evolving life-sciences supercluster.
Outward-looking cooperation and urgent innovation have been hallmarks of the local biotech industry from the start. Founded in 1978, the premier biotech company Biogen knitted together an improbable alliance of government-funded academics, discoveries of a German subsidiary and other firms, and forward-looking NIH-funded clinical investigators. This partnership, fueled by monstrously large amounts of Biogen money, brought forward Avonex, the breakthrough drug for multiple sclerosis.
Success builds on itself: This confluence of academia, medicine, and biotech has prompted most of the world's pharmaceutical companies to establish research and development operations in Massachusetts.
The system, of course, is far from perfect. There are a myriad of ways for conflict to arise along the way to introducing innovative medicines. Disagreements around patent rights and other issues, for example, can result in delays in the introduction of life-saving therapies while draining resources from drug development. We need to continue to find ways to manage conflict and align interests.
Policy makers, meanwhile, can also play a key role in enabling this network to flourish and remain competitive in the face of local, national, and global challenges. Not only do we need to find new ways to ensure that all patients have equal access to medicine, but we need to invest in our talent pool and create incentives for innovation.
At a time of unparalled medical breakthroughs, Massachusetts is a major center of medical innovation. As likely as not, a treatment you will depend on to extend and enhance your life in the next 20 years will come out of a vibrant network of Massachusetts laboratories. And this is no accident.
Joshua Boger is president and CEO of Vertex Pharmaceuticals Inc. of Cambridge. | http://archive.boston.com/news/globe/editorial_opinion/oped/articles/2007/05/07/building_on_a_system_of_outreach_collaboration/ |
Scarce edition from 1896, in well preserved condition. Dark red boards with gilt title (etc.) on spine; 326 pages. The boards and binding are solid and tight with minimal shelfwear. The pages are crisp and clean save for note on the first blank page and previous owner's name on the top of the second and title pages. Thebook is a comprehensive scientific investigation including topics on:
- Psychic Abilities and Development of,
- Examination of the Different Types of Spiritual Phenomena
- The Unscientific Attitude of Spirits
- Why Cannot Spirits Communicate with the Living
- A Psychic Basis for Immortality,
- Telepathy as a Means of Communication in the
"Future Life"
- Spiritism as a Step in the Process of Evolution
- Spiritism in early Christian Antiquity
- Revelations of Science into the Concept of Jesus
- Thunder Considered as a Voice of an Angry God
- Concept of "Man Having a Soul"
- The Kinetic Force of the Soul
- The Human Brain and Suggestion
- The Human Brain Not the Sole Organ of the Mind
- The Development of the Animal Brain
- Necessity for Limiting the Suggestive Power of the Human Mind
- Danger Attending Psychic Activity
Biography
Thomson Jay Hudson (February 22, 1834 - May 26, 1903) — born in Windham, Ohio and died in Detroit, Michigan — known for his three laws of psychic phenomena, which were first published in 1893. Thomson Jay Hudson began observing hypnotism shows and noticed similarities between hypnosis subjects and the trances of Spiritualist mediums. His idea was that any contact with "spirits" was contact with the medium's or the subject's own subconscious. Anything else could be explained by telepathy, which he defined as contact between two or more subconsciouses. Hudson postulated that his theory could explain all forms of spiritualism and had a period of popularity until the carnage of the First World War caused a fresh interest in spiritualism again as psychic mediums emerged to meet the demands of grieving relatives. Hudson spoke of an "objective mind" and a "subjective mind"; and, as he further explained, his theoretical position was that our "mental organization" was such that it seemed as if we had "two minds, each endowed with separate and distinct attributes and powers; each capable, under certain conditions, of independent action"; and, for explanatory purposes, it was entirely irrelevant, argued Hudson, whether we actually had "two distinct minds", whether we only seemed to be "endowed with a dual mental organization", or whether we actually had "one mind [possessed of] certain attributes and powers under some conditions, and certain other attributes and powers under other conditions."
Hudson's Three Laws
Man has two minds: the objective mind (conscious) and the subjective mind (subconscious).
The subjective mind is constantly amenable to control by suggestion.
The subjective mind is incapable of inductive reasoning. | https://blackcatcaboodle.com/products/1896-scientific-demonstration-of-future-life-thomas-j-hudson-psychic-laws |
Job Description:
Be Part of a Global Firm Committed to a Sustainable World
Senior Architect
Doha, Qatar
Parsons’ engineering and construction management staff members create innovative, safe, and sustainable infrastructure in the Kingdom of Saudi Arabia, the United Arab Emirates, Qatar, Oman, Bahrain, and Kuwait. We deliver rail, transit, road, and highway transportation; water conveyance and wastewater treatment; oil and gas; land development; public; and aviation infrastructure to our customers and communities. Parsons creates interconnected communities and world-class infrastructure.
POSITION OVERVIEW:
Review and assess the building permit application drawings’ accuracy against the design regulations and standard including completeness of information and technical / admin requirements, and contribute with master planning / urban design teams in city design regulation improvement and code preparation
Responsibilities:
- Liaise with Lusail city architects and master planners to update and improve the design regulations and design code.
- Lead and /or co-collaborate in building permits processes update and improvement.
- Conduct necessary assessment and provide recommendations of building applications.
- Liaise with other necessary authorities to facilitate the approval process.
- Liaise with investors/consultants and architects to provide guidance and advice regarding building applications within Lusail city district.
- Lead and coordinate with the team in technical reports preparation & implement best practices of architecture at QD.
- Engage in concept designs assessment team of Lusail city developments.
- Handling the mega development processes management and coordination with internal and external relevant authorities to facilitate permitting and various related applications. | https://gulfjobseek.com/job/senior-architect-9/ |
THE BUSINESS CASE
Hong Kong's Community Business shares the value of diversity and inclusion for driving competitive advantage.
INCLUSION, EXCLUSION, ILLUSION AND COLLUSION
An internationally recognized thought leader on unconscious bias, global inclusion and diversity, Helen Turnbull, CEO of Human Facets shares the insights from her 25+ year successful track record in the field of Global Inclusion.
STATUS QUO
To compete in the global digital economy and to consistently deliver value to one's stakeholders and shareholders, it takes a diverse array of skills, talents and personal characteristics for success in the Asia Pacific. Board and Leadership diversity is defined as the percentage of members with different skills, domain knowledge and industry expertise. It also considers the inclusion of diverse ages, genders, ethnic backgrounds and varied international, sectoral and digital experiences.
Whilst many countries in the region are instituting quotas and changing their corporate governance guidelines to require boards to report their level of diversity, the number of women and diverse Directors is increasing at a snail’s pace. In this video Dr Marleen Dielemen, NUS Centre for Corporate Governance, Institutions and Organisations, talks about the Diversity Dividend with a spotlight on Singapore.
The latest Korn Ferry / NUS Asia Pacific 2015 Benchmarking report can be found here.
For research from 2016 through to 2011 scroll down below this video.
Alicia Yi & Tom Pedersen: Diversity Matters - Adding Color to Boards in APAC
Alicia Yi is the Managing Director of Consumer Market for Asia Pacific and Board and CEO Services Practice at Korn Ferry. Based in Singapore, she also serves as the Co-Leader for the Firm's Human Resources Center of Expertise, Asia Pacific. Tom Pedersen is a Senior Partner and Managing Director for Korn Ferry's Leadership and Talent Consulting Practice in Japan. | http://www.diversitydirectory.asia/research |
Putin and Russian History
In the United States, the arts and humanities in the main are flourishing, but one art seems to have disappeared, the political art of losing gracefully. Instead, there is the frenetic search for scapegoats to blame for unexpected and embarrassing defeat. Washington political leaders, rather than wallowing in allegations of foreign electoral interference in U.S. elections, might more properly benefit from examining changes in and the significance of recent events in Russia, a century after the revolutions that ended the Tsarist regime and led to Communist power. For U.S. officials concerned with foreign policy, it is useful to reflect on the nature of the Russian revolutions in 1917, and changes since then.
On May 9, 2017, a massive military parade was held in Red Square in Moscow in which 10,000 troops marched, featuring contingents of female servicewomen dressed in different outfits, and 114 units of equipment were displayed, including medium range and long range surface-to-air missile systems, intercontinental ballistic missile system, and battle tanks.
President Vladimir Putin attended, together with Prime Minister Dmitry Medvedev, took the salute, and displayed a photo of his father in naval uniform. The parade is significant in two ways. It celebrated the 72nd anniversary of the defeat and capitulation in Berlin on May 9, 1945 of Nazi Germany in World War II, and it was a showcase for Russian military might.
But from a political point of view, the parade. honoring the 26 million soldiers and civilians killed in Russia's “Great Patriotic War” was important. Parades were held throughout Russia but the main one in Red Square was central. In essence, this parade replaced in importance the former celebrations of the 1917 revolutions. In reality, there were two revolutions. In February, (really March in the Gregorian calendar) a popular uprising of workers and soldiers led to the abdication of the Tsar. In October (really November) the small Bolshevik group led by Vladimir Lenin dissolved the constituent assembly and captured power.
Putin's remarks after the May 9 parade emphasized the military might of Russia which in 2016, spent $69 billion on its military. He was forthright about Russian strength, but more important for the U.S. policy, Putin also urged international effort to fight terrorism. In words that may well have been aimed at President Donald Trump, the Russian leader said, "Our forces are capable of repelling any kind of attack, but to efficiently combat terrorism, Nazism, extremism, what we need is the consolidation of the international community. Russia will always be on the side in the world of those who fight against these scourges."
What is important is that this celebration of Russian might and defense of country has essentially replaced the celebration of the 1917 revolutions, especially October. It is a commonplace truism that it is difficult if not impossible to predict the future. Russians for several generations have found it not only difficult but perilous to predict the past, though memories linger on and there is, according to recent public opinion polls, a positive view of Lenin’s role in history. Yet, like the aphorism in Virginia Woolf’s Orlando, in Russian political parlance, “But Sasha was from Russia… and sentences are often left unfinished from doubt as how best to end them.”
It is risky to give simple answers to complex problems, but it may be telling that, apart from true believers in Stalinism, only a minority want to celebrate the revolution of October 25, 1917, the military coup and insurrection by Lenin and his Bolshevik group that overthrew the republic established by the February 1917 revolution, and established a dictatorship, and then a totalitarian regime, started by Lenin and fully implemented by Stalin.
The former October ceremonies, starting with a speech by Lenin in Moscow on November 7, 1918, became the main holiday of the year, the glorification of Lenin, the opportunity for revolutionary propaganda, memories of revolutionary heroes, and advocacy of world-wide “proletarian” revolution. In 1996, the day changed to one emphasizing concord and reconciliation. The speech by Putin on May 9, 2017 was devoted, not to any call for revolution, but to the Russian patriotic victory over the Nazis.
It can be argued that the true significance of October and the victory won by the Bolsheviks in the Russian civil war was that it prevented the development of a Western-type democratic system, continuing the slow change in Russian politics after the emancipation of the serfs in 1861, the creation of the Duma in 1905, the abdication of Tsar Nicholas II on March 2, 1917 and the start of the Soviet of Petrograd on February 27, 1917.
Attempts after February to introduce elements of democratic freedom, by Soviets (worker’s councils), factory committees, and popular expression, were crushed by the Bolshevik dictatorship, which turned out to be not “dictatorship of the proletariat,” as Lenin proclaimed, but dictatorship and compulsion by a small group of Bolshevik politicians, and the physical liquidation or persecution of those people, parties, and publications, who disagreed with the ruler, and the imposition of state terror.
Not until the regimes headed by Mikhail Gorbachev and Boris Yeltsin was there any real attempt to modify the system and introduce Western political concepts, and the official renunciation of Marxism and a call for universal Communism. Under Putin, there is a complex arrangement in contemporary Russia, a developing if faltering capitalist economy, limited political freedom, political authoritarianism, a place for the Orthodox Church, a very limited Communist party, absence of official memories of or monuments to Stalin, and an expanding middle class. For President Putin, stability, not revolutionary insurrections throughout the world is the declared objective. The current celebration is patriotic, not revolutionary, focused on the political and military power of the state.
In spite of the allegations of Russian interference in Western elections, Putin has made his position clear, independent management of Russian destiny, Russian global power, and cooperation with the U.S. in the fight against the real threat, international terrorism, not a fictional threat. Washington, particularly Congress, should be really be spending its time reviewing the possibilities of such cooperation, not performing in front of television cameras.
In the United States, the arts and humanities in the main are flourishing, but one art seems to have disappeared, the political art of losing gracefully. Instead, there is the frenetic search for scapegoats to blame for unexpected and embarrassing defeat. Washington political leaders, rather than wallowing in allegations of foreign electoral interference in U.S. elections, might more properly benefit from examining changes in and the significance of recent events in Russia, a century after the revolutions that ended the Tsarist regime and led to Communist power. For U.S. officials concerned with foreign policy, it is useful to reflect on the nature of the Russian revolutions in 1917, and changes since then.
On May 9, 2017, a massive military parade was held in Red Square in Moscow in which 10,000 troops marched, featuring contingents of female servicewomen dressed in different outfits, and 114 units of equipment were displayed, including medium range and long range surface-to-air missile systems, intercontinental ballistic missile system, and battle tanks.
President Vladimir Putin attended, together with Prime Minister Dmitry Medvedev, took the salute, and displayed a photo of his father in naval uniform. The parade is significant in two ways. It celebrated the 72nd anniversary of the defeat and capitulation in Berlin on May 9, 1945 of Nazi Germany in World War II, and it was a showcase for Russian military might.
But from a political point of view, the parade. honoring the 26 million soldiers and civilians killed in Russia's “Great Patriotic War” was important. Parades were held throughout Russia but the main one in Red Square was central. In essence, this parade replaced in importance the former celebrations of the 1917 revolutions. In reality, there were two revolutions. In February, (really March in the Gregorian calendar) a popular uprising of workers and soldiers led to the abdication of the Tsar. In October (really November) the small Bolshevik group led by Vladimir Lenin dissolved the constituent assembly and captured power.
Putin's remarks after the May 9 parade emphasized the military might of Russia which in 2016, spent $69 billion on its military. He was forthright about Russian strength, but more important for the U.S. policy, Putin also urged international effort to fight terrorism. In words that may well have been aimed at President Donald Trump, the Russian leader said, "Our forces are capable of repelling any kind of attack, but to efficiently combat terrorism, Nazism, extremism, what we need is the consolidation of the international community. Russia will always be on the side in the world of those who fight against these scourges."
What is important is that this celebration of Russian might and defense of country has essentially replaced the celebration of the 1917 revolutions, especially October. It is a commonplace truism that it is difficult if not impossible to predict the future. Russians for several generations have found it not only difficult but perilous to predict the past, though memories linger on and there is, according to recent public opinion polls, a positive view of Lenin’s role in history. Yet, like the aphorism in Virginia Woolf’s Orlando, in Russian political parlance, “But Sasha was from Russia… and sentences are often left unfinished from doubt as how best to end them.”
It is risky to give simple answers to complex problems, but it may be telling that, apart from true believers in Stalinism, only a minority want to celebrate the revolution of October 25, 1917, the military coup and insurrection by Lenin and his Bolshevik group that overthrew the republic established by the February 1917 revolution, and established a dictatorship, and then a totalitarian regime, started by Lenin and fully implemented by Stalin.
The former October ceremonies, starting with a speech by Lenin in Moscow on November 7, 1918, became the main holiday of the year, the glorification of Lenin, the opportunity for revolutionary propaganda, memories of revolutionary heroes, and advocacy of world-wide “proletarian” revolution. In 1996, the day changed to one emphasizing concord and reconciliation. The speech by Putin on May 9, 2017 was devoted, not to any call for revolution, but to the Russian patriotic victory over the Nazis.
It can be argued that the true significance of October and the victory won by the Bolsheviks in the Russian civil war was that it prevented the development of a Western-type democratic system, continuing the slow change in Russian politics after the emancipation of the serfs in 1861, the creation of the Duma in 1905, the abdication of Tsar Nicholas II on March 2, 1917 and the start of the Soviet of Petrograd on February 27, 1917.
Attempts after February to introduce elements of democratic freedom, by Soviets (worker’s councils), factory committees, and popular expression, were crushed by the Bolshevik dictatorship, which turned out to be not “dictatorship of the proletariat,” as Lenin proclaimed, but dictatorship and compulsion by a small group of Bolshevik politicians, and the physical liquidation or persecution of those people, parties, and publications, who disagreed with the ruler, and the imposition of state terror.
Not until the regimes headed by Mikhail Gorbachev and Boris Yeltsin was there any real attempt to modify the system and introduce Western political concepts, and the official renunciation of Marxism and a call for universal Communism. Under Putin, there is a complex arrangement in contemporary Russia, a developing if faltering capitalist economy, limited political freedom, political authoritarianism, a place for the Orthodox Church, a very limited Communist party, absence of official memories of or monuments to Stalin, and an expanding middle class. For President Putin, stability, not revolutionary insurrections throughout the world is the declared objective. The current celebration is patriotic, not revolutionary, focused on the political and military power of the state.
In spite of the allegations of Russian interference in Western elections, Putin has made his position clear, independent management of Russian destiny, Russian global power, and cooperation with the U.S. in the fight against the real threat, international terrorism, not a fictional threat. Washington, particularly Congress, should be really be spending its time reviewing the possibilities of such cooperation, not performing in front of television cameras. | |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Stage application under 35 U.S.C. § 371 of International Application PCT/US17/55606 (published as WO 2018/067975 A1), filed Oct. 6, 2017, which claims priority to U.S. patent application Ser. No. 15/287,337, titled “Blood Vessel Sizing Device,” filed on Oct. 6, 2016. Benefit of the filing date of each of these prior applications is hereby claimed. Each of these prior applications is hereby incorporated by reference in its entirety for any and all non-limiting purposes.
BACKGROUND
The present disclosure relates generally to medical devices, and more specifically, to systems and methods for determining dimensions of objects imaged within a radiological image, and for correct positioning of a synthetic structure within a biological feature of a patient.
Determining blood vessel size quickly and accurately is important, for example, for correct positioning of a MEMS device for monitoring of physiological parameters of a patient.
Diagnostic imaging using, for example, x-ray machines in combination with a contrast agent introduced into the blood stream of a patient, may generate images of one or more of the patient's blood vessels. However, the contrast agent may be associated with side effects if used in high quantities.
A need accordingly exists for medical devices and methods that improve the process of determining blood vessel size during and positioning of a MEMS device, while reducing the amount of contrast agent used.
SUMMARY
Aspects of the present disclosure relate to systems, devices, and methods that provide for improved accuracy when positioning of a synthetic structure, such as a MEMS device or a stent, within a biological feature, such as a blood vessel, of a patient. In one example, the present disclosure is directed to medical devices and methods that provide for more accurate measurement of biological features represented in a radiological image. In one implementation, a blood vessel sizing device is configured for placement on the skin of a patient near a feature of interest (e.g. a blood vessel to be imaged). Accordingly, the device may include one or more radiopaque elements, including a target element, and one or more positioning markers having known sizes. When a computer machine generates a radiological image of the blood vessel, the radiopaque elements cause the features of known size to be visible on the generated image (along with the blood vessel image). As such, a clinician may quickly and accurately determine the actual size (true dimension/length) of one or more portions of the blood vessel(s), and identify a portion of a blood vessel suitable for positioning of the synthetic structure.
In one aspect, a method and a non-transitory computer-readable medium comprising computer-executable instructions is described for positioning of a synthetic structure at a biological feature of a patient. The methods and instructions include receiving first radiological image data of an area of a body of a patient as a radiopaque contrast agent is present in one or more biological features within the area. Further, the instructions include identifying, within the received first radiological image data, a radiopaque target element of a sizing device positioned on an area of skin of the patient. The radiopaque target element is compared to one or more biological features to identify a selected biological feature with a dimensional property within an acceptable dimensional range, as indicated by the radiopaque target element. A target location of the selected biological feature relative to one or more radiopaque positioning markers of the sizing device is determined. Further, second radiological image data of the area of the body of the patient is received, and a radiopaque portion of a synthetic structure to be positioned at the selected biological feature is identified. A location of the radiopaque portion of the synthetic structure relative to the target location is further determined.
In another aspect, the systems and methods described herein include a blood vessel sizing device that has a planar base structure with a front surface and a back surface, with the planar base structure configured to be placed on a user's skin during radiological imaging of a target area of the user, and the planar base structure being substantially transparent to light in the visible spectrum. The device further includes a series of radiopaque positioning markers on the front surface spaced apart along a longitudinal axis of the sizing device. Further, a radiopaque target element is positioned on the front surface, and indicates a dimensional range of a biological feature that is acceptable for positioning of a synthetic structure. The device additionally includes an adhesive layer on the back surface configured to adhere the device to the user's skin.
It is accordingly an advantage of the present disclosure to provide a medical device that simplifies and improves blood vessel size determination and positioning of a device within the blood vessel.
It is a further advantage of the present disclosure to provide a method for improving the process for blood vessel size determination and positioning of a device within the blood vessel.
Additional features and advantages are described herein, and will be apparent from the following Detailed Description and the figures.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1
is a plan view of a blood vessel sizing device.
FIG. 2
is a plan view of an alternative implementation of a blood vessel sizing device.
FIG. 3A-3B
depicts alternative implementations of blood vessel sizing devices.
FIG. 4A-4B
schematically depict side views of blood vessel sizing devices.
FIG. 5A-5B
schematically depict side views of alternative implementations of blood vessel sizing devices having deformable structures.
FIG. 6A-6B
schematically depict radiographic images produced by blood vessel sizing devices.
FIG. 7
schematically depicts a radiological image including one or more biological features.
FIG. 8
is a schematic block diagram of an imaging system.
FIG. 9
is a flowchart diagram of one or more processes for automatically determining a true dimension of a future captured in a radiological image.
FIG. 10A-10B
schematically depict a blood vessel sizing device being used on a human patient.
FIGS. 11A-11D
schematically depict various implementations of a device that may be utilized for locating an area of interest within a radiological image.
FIGS. 12A-12B
schematically depict a sizing device, according to one or more aspects described herein.
FIGS. 13A-13B
schematically depict another implementation of a sizing device, according to one or more aspects described herein.
FIGS. 14A-14B
schematically depict yet another implementation of a sizing device, according to one or more aspects described herein.
FIGS. 15A-15B
schematically depict radiological images that include images of a sizing device, according to one or more aspects described herein.
FIG. 16
schematically depicts another implementation of a radiological image that may be produced according to one or more aspects described herein.
FIG. 17
is a flowchart diagram of a process for identification of a suitable site within a biological feature of a patient for positioning of a synthetic structure, according to one or more aspects described herein.
DETAILED DESCRIPTION
In one example, the present disclosure is directed to medical devices and methods that provide for improved accuracy when positioning of a synthetic structure, such as a MEMS device or a stent, within a biological feature, such as a blood vessel, of a patient. In one implementation, a blood vessel sizing device is configured for placement on the skin of a patient near a feature of interest (e.g. a blood vessel to be imaged). Accordingly, the device may include one or more radiopaque elements, including a target element, and one or more positioning markers having known sizes. When a computer machine generates a radiological image of the blood vessel, the radiopaque elements cause the features of known size to be visible on the generated image (along with the blood vessel image). As such, a clinician may quickly and accurately determine the actual size (true dimension/length) of one or more portions of the blood vessel(s), and identify a portion of a blood vessel suitable for positioning for the synthetic structure.
The terms “graphical representation” and “image” are used herein to refer to an output of an imaging technique. Such imaging techniques that generate the graphical representations/images may include one or more processes (which may not be mutually exclusive, and may be combined with other processes, including non-image based processes), to provide an output comprising a graphical representation or image of a target area and/or target object, including an angiogram, MRI, X-Ray, CT scan, myelogram, thermograph, MRN, ultrasound, and/or combinations thereof or other mechanisms that can produce a graphical representation or image of a target object or target area. Further, those of ordinary skill in the art will readily appreciate that the systems and methods described herein may be utilized for non-biological purposes (e.g. for imaging of synthetic materials, and the like), and without departing from the disclosures herein.
FIG. 1
100
100
100
schematically depicts a device configured for providing a mechanism to determine one or more dimensions of features in a graphical representation of an imaged object or area. In one implementation, device may be configured to be placed in an area to be imaged, such as, contact with an area of skin of a patient prior to a medical imaging procedure, and such—device may be utilized to determine a true dimension/length of one or more biological features to be imaged using an imaging technique (e.g. an angiogram using x-rays, and the like).
100
102
102
104
104
106
106
107
107
104
104
106
106
107
107
104
106
107
a
h
a
g
a
g
a
h
a
g
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In particular, device may comprise a base structure . Positioned on the base structure or another surface are shown a plurality concentric-circle elements, numbered as elements -, and a plurality symbols, numbered as symbols -and -. In one example, the elements -, and symbols -and -, may comprise a radiopaque (radiodense) metal, a radiopaque alloy, or another radiopaque material known to those of ordinary skill in the art, and wherein radiopacity will be readily understood to those of ordinary skill in the art as a property of a material that substantially reduces and/or prevents electromagnetic radiation of a certain wavelength/range of wavelengths from passing through the material. In particular, radiopacity may be understood as a property of a material that substantially reduces and/or prevents x-rays from passing through the material. In yet other embodiments, materials that are reactive to certain imaging techniques or chemical processes may also be utilized. In this regard, the elements and symbols herein (including elements , symbols and/or ) may be configured to reduce or prevent transmission of wavelengths such as to appear opaque. In yet other embodiments, they may contain materials known to contrast with an intended target object or target area, such as would be similar to the use of contrast agents in radiological sciences. In yet another embodiment, at least one element and/or symbol may comprise a material that is configured to fluoresce as a result of being imaged or some mechanism utilized prior to or during the imaging process(es).
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In one example, one or more of elements -and/or symbols -may be provided directly, e.g., printed, onto base structure using, e.g. any appropriate printing method known to those of ordinary skill in the art. In other examples, one or more of elements -and/or symbols -and -may be molded into base structure , fastened to base structure by any appropriate fastener, or adhered/welded to base structure , and the like.
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In one example, base structure may comprise one or more of a polymeric material, a glass, a metal, an alloy, or any other material with material properties that give rise to a contrast between base structure and one or more of elements -, symbols -and -, and/or location marker when imaged using electronic radiation of a particular wavelength/range of wavelengths (e.g., x-rays). In one example, base structure may comprise a polymer that is substantially transparent to electromagnetic radiation in the visible spectrum (e.g. visible light). As discussed above, certain elements () or symbols (,) may be configured to be opaque and/or react to different imaging processes.
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In one implementation, base structure may comprise a material with mechanical properties exhibiting a level of rigidity such that base structure does not readily conform to one or more undulations of a surface onto which it is positioned. In one example, this rigidity may be achieved by selecting base structure with a material thickness corresponding to an appropriate level of rigidity. Specifically, in one example, base structure may comprise a polymeric material with a thickness ranging between 0.2 mm and 2.5 mm, or a thickness of 0.25 mm, 0.5 mm, 0.75 mm, 1.0 mm, among many others.
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FIG. 1
In one implementation, concentric-circle elements -may have known diameters. In one example, the diameters of the elements -may measure 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, 14 mm, 16 mm, 20 mm or 30 mm. However, as will be readily apparent to those of ordinary skill in the art, differently sized concentric-circle elements -may be used without departing from the scope of this disclosure. Furthermore, a different number of elements than those eight elements represented as -may be used on device without departing from the scope of this disclosure. In one example, elements -may have a thickness (line thickness) of approximately 0.25 mm, and wherein the diameter of each of the elements -is measured to the center of the radiopaque line that makes up each of the elements -. In one implementation, and as depicted in , one or more symbols (e.g., symbols -and/or -) may intersect one or more of the elements -. In this way, a symbol may serve as an indicator of a dimensional property of a element with which it intersects. For example, a symbol may denote a radius or diameter of a concentric-circle element with which it intersects. In another example, a symbol may not intersect with an element for which it denotes a dimensional property. In the specific example depicted , a plurality of symbols denote a plurality of diameters of respective concentric-circle elements. Specifically, symbols and are shown as being diametrically opposed on the concentric-circle element , and indicate that concentric-circle element has a diameter of 4 mm. Similarly, symbols and indicate that concentric-circle element has a diameter of 6 mm; symbols and indicate that concentric-circle element has a diameter of 8 mm; symbols and indicate that concentric-circle elements has a diameter of 10 mm; symbols and indicate that concentric-circle element has a diameter of 14 mm; symbols and indicate that concentric-circle element has a diameter of 16 mm; and symbols and indicate that concentric-circle element has a diameter of 20 mm. Yet in another embodiment, one or more elements may have a diameter of 30 mm.
FIG. 1
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In one example, and as depicted in , symbols -are embodied as numerals (e.g. Arabic numerals). In another implementation, different symbols may be used to denote a dimensional property (e.g., a diameter) of one or more of concentric-circle elements -. For example, symbols -may be computer-readable shapes and/or patterns (e.g. barcodes, and the like). Indeed, in certain embodiments, a symbol or marker may provide computer-readable indicia that may be detected (including automatically) before, during, or after an imaging process. In certain embodiments, the symbol or indicia may not readily convey the dimensional property represented without prior knowledge to its correlation to the dimensional property.
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In one implementation, device has a location marker , wherein location marker . Location marker, like the elements and symbols described herein, may comprise a radiopaque area, contrast materials, and/or fluorescent materials. In one implementation, location marker has a surface area of between 18 and 22 mm. Location marker may be positioned a predetermined distance from at least one or more of elements , symbols and/or symbols . In one embodiment, the diameter of the a concentric circle, such as circle , may be less than, equal to, or larger than the distance from location marker to that circle, the center of the concentric circles , or another location associated with the circles or symbols /. In yet another embodiment, a dimension (e.g., diameter) of marker may be proportional to one or more aspects of the elements (depicted as circles) , and/or symbols /.
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In one example, electromagnetic radiation of a certain wavelength (e.g. x-rays) may not pass through, and/or the transmission of the radiation may be substantially attenuated through elements -, symbols -and -, and/or location marker . Accordingly, a radiological image (otherwise referred to as a radiograph, or x-ray, and the like) of a biological and/or synthetic feature may include a representation or image corresponding to one or more of elements -, symbols -and -, and location marker .
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In one implementation, location of one or more of elements -, and/or symbols -and -may be aided by location marker , wherein location marker has a comparatively larger radiopaque surface area than any one element (e.g., of elements -) or symbol -or -. As such, the comparatively larger radiopaque surface area of location marker may correspond to a larger feature within a radiological image produced using device . Accordingly, location marker may be relatively more visible to a user, and hence, more quickly recognized in a produced radiological image. One or more of elements , symbols /, and/or marker may be configured to have a first appearance when imaged under a first imaging process and second appearance when imaged under a second image process. This may be beneficial for a few reasons. In one embodiment, it may allow the detection of whether the proper procedure was used, and/or what type of procedure was used. In one embodiment, the first appearance may be configured to present itself on a graphical representation when a first wavelength was used and the second appearance may be associated with a second wavelength, such as one that may be erroneously used for a specific instance.
FIG. 1
FIG. 2
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depicts device having base structure with an outer perimeter having a discrete shape. Those of ordinary skill in the art will recognize that base structure (and/or entire device ) may have any shape, and without departing from the scope of this disclosure. In this way, one alternative implementation of device is depicted in .
FIG. 2
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depicts device , which may be similar in one or more aspects to device from . In particular, device has a base structure that may be similar in structural features to base structure from . In this example, base structure is embodied with outer perimeter , which exhibits a different shape than outer perimeter of device . Device further includes a scale located thereon. In one example, scale may comprise one or more elements like or similar to elements -and/or symbols -and -from , including in relation to one or more of their quantity, size, shape, proportional dimensions, radio opacity, and combinations thereof. Further, location marker may be similar (in terms of dimension, location, and/or other attributes, such as those described above) to location marker from .
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One or more devices, such as devices or , may include a unique identifier. In one example, device comprises a unique identifier . Unique identifier may be provided, e.g., printed, onto base structure . In one specific example, unique identifier may comprise a radiopaque material. In one example, unique identifier may be used to associate one or more data points with device . For example, unique identifier may be used to identify a patient imaged using device (e.g. to produce, in one example, an x-ray), the specific imaging equipment, personnel employing the imaging technique, date, time, locational information, and combinations thereof, among others. Those of ordinary skill in the art will readily understand that unique identifier may be utilized to associate a device, such as device or device , with any type of stored information, wherein the unique identifier itself may store said information, or wherein unique identifier may comprise a sequence of digits and/or symbols that may be used to look up information stored in a collection of information, whether electronic or not, separate from the device /.
FIG. 3A
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FIG. 2
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depicts a blood vessel sizing device which may be similar in one or more aspects to one or more of devices and/or from and , respectively. Device is shown as comprising a base structure , wherein, in one example, base structure may be similar to base structure and/or from and , respectively. Furthermore, device has a scale , which may be similar to scale from .
FIG. 3A
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In the example depicted in , base structure comprises a substantially transparent (e.g. to light in the visible spectrum) polymeric material. Accordingly, this transparency may be utilized when positioning device on an area of skin of a patient and/or other surface (biological or synthetic) prior to an imaging procedure (e.g. an x-ray).
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FIG. 4
FIG. 5
In one example, device may comprise a perimeter area , wherein perimeter area may represent an area of the base structure to which one or more of an adhesive layer or a deformable structure (described further in relation to and ) may be affixed. In one example, that adhesive layer and/or deformable structure (not pictured) affixed to perimeter area may be opaque to light in the visible spectrum and/or spectrum of wavelengths utilized by an imaging process. In one implementation in which the perimeter area is opaque to light in the visible spectrum, perimeter area encloses a window of base structure , wherein that area of base structure designated as window remains substantially transparent to light in the visible spectrum. As such, window facilitates visual positioning of device on an area of interest prior to an imaging procedure while perimeter area is substantially opaque. In certain embodiments, the perimeter area may be opaque with respect to only one of (a) light in the visible spectrum and (b) spectrum of wavelengths utilized by an imaging process to capture the target object or target area.
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FIG. 3A
It will be readily apparent to those of skill in the art that while perimeter area is depicted in with a particular shape, many alternative shapes for perimeter area and/or window may be realized without departing from the scope of this disclosure. Furthermore, in another example, perimeter area may cover substantially the same area as base structure , and without departing from the scope of this disclosure.
FIG. 3B
FIG. 3A
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depicts a device , wherein device may be similar to device from . Similarly to device , device may have a substantially transparent base structure . Furthermore, base structure may have a perimeter area , wherein perimeter area represents an area to which one or more of an adhesive layer and/or a deformable structure may be affixed. Accordingly, perimeter area may be substantially opaque to light in the visible spectrum. As such, visual placement of device on an area of interest may be facilitated by a substantially transparent window . It is noted that window , and similarly for window , while being substantially transparent to light in the visible spectrum, include radiopaque scales and , wherein scales and may be substantially opaque to light in the visible and/or x-ray spectrum, among others.
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In one example implementation, device comprises a tab structure , wherein tab structure may be an area of base structure that is non-adhesive. As such, structure may facilitate removal of device from an area to which device was adhered prior to an imaging procedure. An adhesive layer may be positioned on the entirety of or just a portion of the perimeter area .
FIG. 4A
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FIG. 2
FIG. 3A-3B
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schematically depicts a side view of an imaging device , similar to devices , , and/or (wherein , , and depict plan views of devices , , and/or ). As such, device comprises a base structure having a front surface and a back surface . A scale , which may be similar in one or more aspects to scales and , is positioned on the front surface of base structure . As previously described, scale may be printed, adhered, welded, or joined by any other means known to those of ordinary skill in the art to a surface, such as the front surface . The thickness of base structure is represented as thickness , and which may range between 0.2 mm and 2.5 mm, and the like.
FIG. 4B
FIG. 4A
FIG. 3A
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Turning to , device from is depicted having an alternative configuration, and including an adhesive layer on the back surface of base structure . In one example, adhesive layer may cover the entire surface area of the back surface of base structure . In another example, adhesive layer may only partially cover the back surface . Specifically, in one example, adhesive layer may cover an outer perimeter area, such as perimeter area from .
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It will be readily apparent to those of skill in the art that adhesive layer may comprise any known adhesive. In one example, adhesive layer may comprise a medical adhesive configured to temporarily and removably bond a structure, such as device , to an area of skin of a patient.
FIG. 5A
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schematically depicts device . In one example, device may be similar in one or more aspects, to devices , , , and/or previously described. Accordingly, device may comprise a base structure , which may be similar to one or more aspects described herein of base structure , , and/or . A scale may be positioned on a front surface of base structure, and a deformable structure may be positioned on a back surface of base structure .
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As such, a front surface of deformable structure may be adhered to the back surface of base structure by any methodology known to those of ordinary skill in the art, and including, but not limited to, adhesion, molding, fastening, and/or welding, among others. Additionally, an adhesive layer , similar to adhesive layer , may be positioned on part or all of a back surface of deformable structure . It should be understood that deformable structure and adhesive layer may be the same layer. Therefore, discussion of a deformable structure or adhesive layer may be interpreted as a single layer that has both properties.
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Deformable structure may comprise a material with physical properties (e.g. hardness) allowing for deformation (compression, and the like) without failure of the material. Accordingly, deformable structure may comprise a sponge-like material which may be a synthetic foam, or any other material with mechanical properties suitable for deformation. Furthermore, in one example, deformable structure may have a thickness ranging between 0.5 mm and 15 mm, or a thickness of 1 mm, 2 mm, 5 mm, 10 mm, 15 mm, among others.
FIG. 5B
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schematically depicts device adhered to an uneven surface . As such, deformable structure is depicted in a compressed state, wherein the back surface of deformable structure conforms to the undulations of uneven surface , while the front surface of the deformable structure remains substantially planar. Accordingly, base structure of device , in addition to the radiopaque scale thereon, also remain substantially planar while device is adhered to uneven surface .
FIG. 6A
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schematically depicts a radiographic image resulting from electromagnetic radiation of a certain wavelength (or range of wavelengths), e.g. x-rays, incident on a device which may be laid over a passageway of a living being, such as a blood vessel of a human. Accordingly, device may be similar in one or more of the aspects described herein to one or more of devices , , , , and/or . In particular, schematically depicts a source emitting electromagnetic radiation that is incident upon a base structure , a radiopaque scale , and a location marker of device . In one example, part, or all, of the electromagnetic radiation incident on scale and location marker is absorbed. Yet, other embodiments may have materials that get excited by, or otherwise react to the imaging process or other process used in conjunction with the imaging process. Accordingly, the radiographic image produced upon detection of the electromagnetic radiation transmitted through base structure includes a radiopaque scale image and a location marker image .
FIG. 6B
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depicts the same device , but angled, at angle , with respect to source along a defined plane. Those skilled in the art will appreciate that the device may be angled with respect to the source along multiple planes, however, for sake of understanding aspects of the innovative embodiment, only a single plane is discussed. Because the device is angled with respect to the source, the electromagnetic radiation emitted from source is no longer orthogonal to base structure (electromagnetic radiation now incident upon base structure at an angle of (90°−[angle ]°)). As such, the radiographic image produced as a result of the angle between the incident radiation and device results in a radiopaque scale marker image and a location marker image having ellipsoidal shapes, as depicted.
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The distortion of the radiopaque scale marker image and location marker image may be regarded as an error of parallax, wherein, among others, minor axis of radiopaque scale marker no longer represents a true length. However, due to the concentric-circle design of scale marker (e.g. radiopaque concentric-circle elements -from ), the resulting radiopaque scale marker image includes at least one true length. In particular, the true length of concentric-circle elements -is represented in radiopaque scale marker image along the longest axis (major axis) of that ellipsoidal image of radiopaque scale marker . As such, a user may determine the longest axis of radiopaque scale marker image , and measure one or more true lengths of one or more concentric-circle elements -along said axis . In this regard, although there are two axes shown ( and ), those skilled in the art will realize that any straight line that passes through the center of a concentric circle can serve as an axis. In this regard, the closest axis to the true axis may be set to the nearest degree, of the circle, or nearest half degree or whole number of degrees. Advantageously, device , and in particular, the concentric-circle elements -, thereby allow a user to avoid errors of parallax.
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FIG. 1
In one example, device may not comprise a rigid structure. In particular, in one example, base structure may bend in one or more directions. For example, base structure may substantially conform to one or more areas of curvature of the human body onto which it is a fixed. As such, due to bending of base structure along one or more axes, a resulting marker image produced by source may be distorted along multiple axes. For example, distortion of marker image may result in a first major axis associated with the depicted 20 mm (which may be other dimensions, such as 30 mm or 3 cm) concentric circle of marker image (e.g. circle from ), and a second major axis associated with, in one example the 10 mm concentric circle of marker image (e.g. circle from ), wherein the first and the second major axes are not parallel. As such, in one example, it may be advantageous for a user to determine a concentric circle size, from those concentric circle sizes depicted in marker image (e.g. 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, 14 mm, 16 mm, 20 mm, or 30 cm among others) that most closely matches a dimension of an imaged feature. In this way, a user may identify a first major axis in marker image to be used in association with a first imaged feature, wherein this first major axis is a most accurate axis visible in marker image having a dimension that is close to a dimension to be measured in the first imaged feature. Accordingly, a user may identify a second major axis in marker image , due to distortion of marker image as a result of bending of base structure along one or more axes. As such, the second major axis may not be parallel to the first major axis identified. Accordingly, the second major axis may be a most accurate axis visible in marker image having a dimension that is close to a dimension to be measured in a second imaged feature.
FIG. 7
FIG. 7
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schematically depicts a radiological image , that defined a field of view or target area including one or more biological features (which may include a target object. In particular, the image of may be an angiogram. Those of ordinary skill in the art will readily understand various methodologies for carrying out an angiogram, which include, among others, use of contrast agents to view blood vessels, and the like. Accordingly, any known technique for angiography or other radiographic imaging may be employed with the systems and methods described herein, and without departing from these disclosures. Furthermore, image may be computer-generated, or may be produced by the detection of electromagnetic radiation (e.g. x-rays) by a film.
FIG. 7
FIG. 1
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depicts a plurality of blood vessels comprising at least a portion of the carotid artery , and one exemplary branching blood vessel is labeled as vessel . In one example, it may be desirable to obtain one or more dimensions of biological features from a given radiological image . Accordingly, in one example, one or more dimensions of a stenosis may be obtained from radiological image . In one implementation, a device, such as device , , , , and/or may be positioned on a surface of interest, and within the field of view of a radiological image to be produced. In one specific example, a scale image (which may comprise a plurality of elements and symbols) may be included in a radiological image produced. As such, one or more true dimensions of one or more biological features (e.g. a blood vessel width ) may be determined using one or more concentric-circle elements of the unknown size (e.g. elements -from ) of scale image .
FIG. 8
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schematically depicts an imaging system . Specifically, system includes a computer having a processor , memory , and an interface . Computer is further connected to a user interface , a source , and a detector . It will be readily apparent to those of ordinary skill in the art that connections between devices , , , and/or may be wired or wireless, and using any known network type and/or communication protocol. For example, communication between one or more of devices , , , and/or may be through a local area network (LAN), a wide area network (WAN), or the Internet, and using a communication protocol including one or more of the Transmission Control Protocol (TCP), the Internet Protocol (IP), or the User Datagram Protocol (UDP), among many others.
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Processor may be a general-purpose central processing unit, or a dedicated and specialized processing chip. Processor may contain a single processing core, or multiple cores acting in parallel, and the like. Memory may be volatile or persistent, and may include one or more of read only memory (ROM), random access memory (RAM), a solid state hard drive (SSD), or memory using optical disc media (CD, DVD, and the like), among others. Interface may comprise those hardware and/or software components for connection of computer to one or more devices , , and/or across a network. Furthermore, user interface may comprise one or more of a display and/or a control interface for receiving instructions from user. Source may comprise a source of electromagnetic radiation (e.g. x-rays) suitable for radiographic imaging. Accordingly, detector may comprise an electronic detection device sensitive to electromagnetic radiation emitted from source , and such that the electromagnetic radiation received by detector may be used to construct a digital image.
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Element represents an area of skin of a patient to be imaged using source and detector . Positioned on said area of skin of a patient is a blood vessel sizing device , wherein the device may be similar to one or more of those devices (, , , , and/or ) previously described. Accordingly, one or more features of device , such as, for example, a radiopaque scale, such as radiopaque scale , may be included in a resulting image constructed by computer .
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In one example, a user of system may identify a biological feature within a radiological image, wherein said image may be a real-time digital image produced by computer from data received from detector . For example, a user may identify a one or more passageways (blood vessels) and/or one or more objects within passage ways (blood clots), among others. In one example, it may be desirable for a user to determine a true dimension of one or more biological features present in an image produced by system . Accordingly, a user may input one or more instructions, via interface , identifying one or more biological features of interest within an image produced by system , and visible to a user at user interface . Subsequently, one or more identified features of interest may be compared to an image produced by blood vessel sizing device , wherein said image may be similar to a scale, such as scale , among others. As such, one or more known sizes/dimensions of said scales and/or may be compared to the one or more identified features of interest, and a true dimension may be determined. Furthermore, it will be apparent to those of ordinary skill that blood vessel size or device is agnostic to the type of imaging equipment used, in addition to the magnification and/or specific image manipulation processes applied to the data detected by detector .
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FIG. 1
FIG. 6B
In one example, a user may manually compare a length property of a biological feature visible within an image produced by system to one or more known dimensions of a radiopaque scale present within said image. For example, a user may measure a width of a blood vessel, as shown in an image produced by system , using a calipers. However, due to the magnification/scaling and/or other image manipulation steps carried out on the data received from detector , this length measured by the calipers may not be a true dimension of the width of the blood vessel. Accordingly, the user may compare the length measured by the calipers to one or more concentric-circle elements (e.g. elements -from ) visible within a radiopaque scale (e.g. radiopaque scale and/or ), and wherein the radiopaque scale is visible within the same radiological image as the blood vessel of interest (e.g the visible radiopaque scale and/or will have been subject the same scaling and/or other image manipulation processes such that a direct comparison between the length measured with the calipers, and one or more lengths from the radiopaque scale is still possible). In doing so, the user may compare the measured length from the calipers to the major axis (e.g. as discussed in relation to ) of the radiopaque scale, and by comparison to one or more of the known dimensions of the concentric-circle elements, determine a true dimension of the blood vessel width. Furthermore, it will be readily apparent to those of skill that any mechanical measurement device may be utilized for measuring a length property of a biological feature. For example, a user may utilize a ruler, measuring tape, or calipers, among many others.
FIG. 9
In another example, one or more true dimensions of an identified biological feature may be determined by an automated process. One example of such an automated process is described in relation to .
FIG. 9
FIG. 9
FIG. 8
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is a flowchart that may be implemented in the automatic determination of a true dimension of a feature captured in a radiological image (e.g., radiograph/x-ray). In one example, the description in may be used in conjunction with imaging system from . Image data may be received from a detector, such as detector (e.g., block ). In one example, this image data may include information related to one or more biological features (tissues, organs, blood vessels, blood clots, and the like). A dimensional property (e.g., a length property) of the one or more biological features of interest within the received image data may be obtained (e.g., block , which may follow block ).
904
In an example embodiment, block may represent one or more processes to determine a length of one or more features within a radiological image using an arbitrary length metric (e.g. a number of screen pixels, and the like). In this way, due to one or more scaling and/or other image manipulation processes carried out on the image data used to create the radiological image, a true dimension of the one or more features is not readily known.
104
104
906
906
904
906
a
h
FIG. 1
One or more elements from image data that correspond to concentric-circle elements, such as those elements -from , may be identified (e.g., block ). Block may occur in the absence of block . Those of ordinary skill in the art will readily understand that any computer image recognition processes may be utilized with the one or more processes of block , and without departing from the scope of this disclosure.
106
106
107
107
904
906
910
624
104
104
a
g
a
g
a
h
FIG. 6B
FIG. 6B
Symbols, such as for example, -and -, may be identified from the image data. This may occur before, during, after and/or in absence of blocks /. In accordance with further embodiments, a major axis of one or more identified concentric-circle elements may be determined, such as at block . In this way, and as described in relation to , a longest axis of a radiopaque scale marker image, such as radiopaque scale marker image from , may be used to read known lengths of one or more concentric-circle elements -without an error of parallax (and/or with a statistically significant reduction in an error of parallax.
624
914
A dimensional property (e.g., the length property) of a biological feature may be compared to one or more dimensions (e.g., lengths) of concentric-circle elements along the determined major axis of a radiopaque scale marker image, such as radiopaque scale marker image . Upon comparison of the determined length property of the biological feature to the corresponding concentric-circle elements of the same length (or interpolating/extrapolating from one or more known dimensions of concentric-circle elements), a true dimension value may be determined. As such, the determined dimensional property (e.g., the length) of the biological feature may be converted into a true dimension value (e.g., block ).
820
916
FIG. 8
A true dimension value may be communicated to a user, such as via user interface from , which may occur at example block .
FIG. 10A
FIG. 10A
FIG. 10A
FIG. 10
1004
1004
1002
1004
100
200
300
400
1002
1010
1010
1010
schematically depicts an example implementation of device being used. In particular, schematically depicts device positioned on a neck area of a human patient . Accordingly, in one implementation, device may be similar to device , , , or , and the like. Following from , B schematically depicts patient being imaged using imaging device . As will be apparent to those of ordinary skill in the art from the foregoing disclosures described herein, imaging device may be, among others, part of an x-ray device for performing an angiogram. In other implementations, device may be a part of an MRI device, a CT device, a myelogram device, a thermograph device, an MRN device, an ultrasound device, and/or combinations thereof, among others.
FIG. 10B
1010
1006
1004
1008
1008
Accordingly, as schematically depicted in , imaging device may image a region that includes both device and, in one example, blood vessel . In one specific example, blood vessel may be a carotid artery, among others.
FIGS. 11A-11D
FIGS. 11A-11D
FIG. 11A
FIG. 11A
FIG. 11A
FIG. 11A
1100
1102
706
100
1106
1104
1108
1106
1104
1100
1104
schematically depict various implementations of a device that may be utilized for locating an area of interest within a radiological image. In certain embodiments disclosed herein, the device may be used to locate or estimate the location of a feature or area of interest of: (1) a first image of a first area, wherein a first feature is captured under a first image criteria; and (2) a second image that comprises at least the same first area, wherein the same feature is present but not captured or captured to a less degree, under a second image criteria, Non-limiting examples are discussed in relation to . In one example, depicts a radiological image that includes a scale image , which may be similar to scale image , and generated as a result of one or more imaging processes of a device, such as device , and the like. Additionally, depicts a schematic view of a blood vessel having a feature of interest , which may be, in one example, a stenosis, and the like. Furthermore, depicts a branching vessel . In one example, vessel and feature may be visible within an image (e.g., radiological image) through use of a contrast agent. In this regard, may represent a first image of a first area, wherein the feature may be a first feature that is captured under the specific capturing conditions, such as using a radiograph and contrast agent (or specific type/dosage of agent).
FIG. 11B
FIG. 11A
FIG. 11B
1140
1100
1102
1104
1102
1104
1120
1122
1140
1140
1102
1104
1106
1140
1104
1122
1104
1102
1120
1106
1104
1140
1104
1102
1104
schematically depicts a radiological image that is similar to image from . In particular, schematically depicts scale image being utilized to locate a feature of interest . Specifically, a position of scale image may be noted relative to feature . Accordingly, those lines and may represent imaginary lines, or visible lines depicted on an electronic interface (computer screen) or other representation of image (e.g. a printed copy of image , and the like) that may be traced out from the center of scale image , and delimiting the ends of feature within vessel . For example, a user (a clinician or otherwise) viewing image may note that a “top” end of feature corresponds to a “3 o'clock position” at an outer concentric-circle element (that largest 20 mm circular element depicted, which may be larger or smaller, including, for example, 30 mm or 3 cm), and delimited by line . Similarly, the user may note that a “bottom” end of feature corresponds approximately to a “4 o'clock position” at the outer concentric circle of scale image , and delimited by line . As such, while vessel and feature are visible in image through use of a contrast agent, noting a position of feature relative to scale image may allow said feature to be located without using further contrast agent in subsequent images having a same field of view.
1100
1106
1104
1104
In furtherance of this example, those of ordinary skill in the art will readily understand various contrast agents, otherwise referred to as radiocontrast agents, or contrast media, among others, may be used to improve visibility of one or more blood vessels, and associated features, when imaged using x-ray-based imaging techniques. Accordingly, in one example, a contrast agent may be utilized in image to view vessel , and may include an iodinated (iodine-based) contrast agent, among others. As such, those of ordinary skill in the art will understand that while contrast agents are generally considered safe for use during in vivo imaging, there exist various side effects that may be associated with the use of contrast agents. For example, contrast agents may have a detrimental impact upon kidney function, or may, in some instances, lead to higher rates of blood clotting, among others. As such, it may be desirable for an imaging process to reduce an amount of contrast agent utilized to, in one example, image a vessel for positioning of a stent, among others. Thus, a second image (which may be a subsequent frame in a live video capture) may be the same area and feature (e.g., feature ), however, blood flow has moved the contrast agent, and as such, feature may be less visible or not visible.
FIG. 11C
FIG. 11A
FIG. 11C
FIG. 11C
FIG. 11B
FIG. 11B
FIG. 11B
FIG. 11B
FIG. 11D
1102
1106
1106
1110
1112
1110
1112
1106
1150
1110
1112
1106
1140
1150
1110
1112
1106
1150
1104
1102
1120
1122
1104
1150
1120
1122
1104
1130
1160
1102
1120
1122
1130
1106
1106
1160
1120
1122
schematically depicts scale image being utilized to locate a feature within a vessel without using contrast agent. As such, respective to , may be considered a second image that comprises at least the same first area, wherein the same feature is present but not captured or captured to a less degree, under a second image criteria (e.g., no or less contrast agent). In one embodiment, at least a portion of the vessel itself may be the feature that is less visible or not visible in the second image (or any image that is not the first image). In particular, an outline of vessel is depicted in , having a first side wall , and a second sidewall . However, sidewalls and outlining vessel are included for clarity within radiological image . As such, sidewalls and represent one or more lengths of blood vessel that were previously visible within the radiological image from through use of a contrast agent, but which may no longer be visible, or may have diminished visibility, within radiological image due to an absence of a contrast agent. As such, it may be assumed that sidewalls and/or of the vessel are not clearly visible within radiological image in accordance to one embodiment. However, having noted the position of feature (which also may not be visible or is of reduced visibility relative to scale image from ), lines and/or may be utilized to locate, approximately, feature (from ) within image . As such, lines and/or may be utilized to position, in one example, a stent, at the feature of interest from , and without using, or using a reduced amount of a contrast agent. Turning to , stent may be positioned in image relative to scale image , and utilizing that relative positioning noted using lines and/or , and the like. Specifically, stent may be moved into an area of vessel (vessel may not be clearly visible within image due to absence of contrast agent, and the like) by positioning relative to lines and .
1100
1140
1150
1160
1100
1140
1150
1116
Those of ordinary skill in the art will understand that images , , , and/or may be still images, or may be “live” images that are periodically updated. In one example, one or more of said images may be updated as a frame rate of six frames per second, however those of ordinary skill in the art will understand that any update/refresh rate may be utilized without departing from the scope of these disclosures. Additionally, those of ordinary skill in the art will understand that's images , , , and/or may be generated using any appropriate imaging technology including, among others, computed tomography and/or radiography, among many others.
FIG. 12A
FIG. 12A
1200
1200
1202
1202
1202
102
100
202
200
302
300
402
400
502
500
602
600
1200
1204
1204
1206
1204
1204
1204
1204
1200
1208
1204
1204
1206
1204
1204
1206
1204
1204
1204
1204
1200
1204
1204
a
t
a
t
c
d
a
t
c
d
a
t
a
t
a
t
schematically depicts an example sizing device , according to one or more aspects described herein. In particular, the sizing device has a base structure . In one example, the base structure may be planar, and may be configured to be placed on a user's skin during radiological imaging of a target area of the user. Further, the base structure may be similar to one or more of base structure of device , base structure of device , base structure of device , base structure of device , base structure of device , and/or of device . Additionally, the sizing device may include a series of positioning markers -and a target element . The series of positioning markers -may be uniformly/equally spaced apart from one another (with the exception of markers and ) along a longitudinal axis of the device that is parallel to arrow . In one example, a spacing between an adjacent two of the positioning markers -may measure 10 mm. However, any spacing value may be utilized, without departing from the scope of these disclosures. In the specific example depicted in , the target element is centered at a halfway point between positioning markers and . However, the target element may be positioned between other markers in the series -, or replace the first or last positioning marker within the series -, without departing from the scope of these disclosures. Further, the sizing device may be embodied with less than or more than the depicted positioning markers -, without departing from the scope of these disclosures.
1204
1204
1206
1204
1204
1206
104
104
106
106
107
107
206
306
346
408
504
604
a
t
a
t
a
h
a
g
a
g
FIG. 1
FIG. 2
FIG. 3A
FIG. 3B
FIGS. 4A and 4B
FIGS. 5A and 5B
FIGS. 6A and 6B
In one example, the series of positioning markers -and the target element may comprise one or more radiopaque materials. As such, the series of positioning markers -and the target element may utilize a material similar to those described in relation to elements -, -and -from , scale from , scale from , scale from , scale from , scale from , and/or scale from , among others.
FIG. 12B
FIG. 12A
FIG. 12B
FIG. 12B
1200
1202
1204
1204
1204
1204
1206
1204
1204
1204
1208
1210
1208
1208
1204
1204
1204
1204
1208
a
b
c
d
c
d
a
a
b
c
d
schematically depicts a more detailed view of a portion of the sizing device of , according to one or more aspects described herein. In particular, schematically depicts a portion of the base structure , and positioning markers , , , and , with the target element spaced between positioning markers and . In the depicted example, each positioning marker (e.g. positioning marker ) includes a readable symbol and a notch associated with the readable symbol . In the depicted example of , the symbols (e.g. ) associated with positioning markers , , , and include Arabic numerals. However, in other implementations, different symbols may be utilized. For example, readable symbol may include computer-readable shapes and/or patterns (e.g. barcodes, and the like), without departing from the scope of these disclosures.
1206
1212
1204
1204
1206
1214
1216
1218
1216
1218
1206
802
1206
c
d
In one example, the target element includes a central marker that is centered at a point equidistant to positioning markers and . Additionally, the target element includes a radiopaque ring that has an inner diameter and an outer diameter . In one example, the inner diameter and an outer diameter may indicate a minimum and a maximum size (e.g., either recommended, absolute, acceptable, or other dimensions for positioning of a synthetic structure (e.g. a MEMS device) within a biological feature (e.g. a blood vessel) of a patient. For example, the acceptable dimensions may represent the acceptable diameter of a blood vessel within an imaged area to receive a medical device. However, the target element may utilize any dimensions, which may be chosen for any purpose, without departing from the scope of these disclosures. Where described herein, a MEMS device may include, among others, a micro-electromechanical systems (MEMS) sensor device that may be utilized to measure blood pressure and/or blood flow rate of a patient, and/or to communicate related data wirelessly to a remote computer device (e.g. computer device ). As such, this MEMS device may be positioned within a blood vessel of a user that meets one or more criteria, which may include a blood vessel diameter criteria (which may be visually conveyed with target element or a portion thereof). In one specific example, a specific MEMS device may be deployed in a blood vessel having a diameter measuring between 7 mm and 10 mm. However, it is contemplated that this disclosure should not be limited to this diameter range, and any sizing constraints may be utilized, without departing from the scope of these disclosures.
1206
1220
1222
1216
1218
1214
1216
1218
1220
1222
1220
1222
FIG. 12B
FIG. 12B
The target element may additionally include symbols and indicating the size of the inner diameter and the outer diameter of the radiopaque ring , respectively. In the specific example depicted in , the inner diameter and the outer diameter may measure 7 mm and 10 mm, respectively, as indicated by symbols and . However, any dimensions may be utilized, without departing from the scope of these disclosures. Additionally, symbols and may include additional or alternative symbols to those Arabic numerals depicted in .
1206
1204
1204
1224
1206
1204
1224
1206
1204
1206
c
d
a
a
In one example, the target element may be located between positioning marker and positioning marker such that the distance , corresponding to the distance between the center of the target element , and the first positioning marker in the series of positioning markers, indicates a length of a synthetic structure (e.g. a MEMS device), or a portion thereof, to be positioned within a biological feature (e.g. a blood vessel) of a patient. In one example, the length may correspond to a length of a synthetic structure, whereby the length of the synthetic structure may not be fully visible within a radiological image as a result of a portion of the synthetic structure not being radiopaque. As such, the positioning of the target element spaced apart from the first positioning marker may, in one example, indicate to a user that a synthetic structure is longer than it appears in a radiological image. Thus, targeting element (as well as others envisioned herein) may be utilized as relative locational devices with respect to features captured within radiographic data, sizing guides with respect to one or more biological features, such as blood vessels for receiving a specific device, as well as positional devices to ensure devices and/or portions thereof that may not be readily visible in the radiographic data are properly guided and/or placed.
1206
104
104
106
106
107
107
a
h
a
g
a
g
FIG. 1
In another implementation, the target element may include one or more concentric circles similar to those described in relation to elements -, symbols -, and -from .
FIG. 13A
FIG. 12A
1300
1300
1200
1302
1202
1304
1304
1304
1304
1300
1308
1304
1304
1204
1204
1304
1304
a
t
a
t
a
t
a
t
a
t
schematically depicts another implementation of a sizing device , according to one or more aspects described herein. The sizing device may be similar to sizing device from , and include a base structure similar to the base structure , and a series of positioning markers -. The positioning markers -may be equally spaced apart from one another along a longitudinal axis of the device that is parallel to our . In one example, a spacing between an adjacent two of the positioning markers -may measure 10 mm. However, any spacing value may be utilized, without departing from the scope of these disclosures. Similar to the positioning markers -, positioning markers -may comprise one or more radiopaque materials.
1300
1306
1306
1304
1306
1300
a
FIG. 13B
FIG. 13A
The sizing device may additionally include a target element . In the depicted example, the target element is positioned before the first of the positioning markers . This target element is more clearly depicted in , which schematically depicts a more detailed view of a portion of the sizing device of , according to one or more aspects described herein.
1306
104
104
106
106
107
107
a
h
a
g
a
g
FIG. 1
In one example, the target element includes multiple concentric circular shapes and symbols similar to elements -, -and -described in relation to .
1306
1304
1310
1310
1312
1304
1304
1310
1312
a
a
b
In one implementation, the target element may be positioned with its center spaced away from the first positioning marker by distance . Further, distance may be equal to the distance between positioning markers and . As previously described, this distance and/or may be equal to 10 mm, but may be embodied with any length, without departing from the scope of these disclosures.
1306
1304
1304
1206
1310
1312
1304
1304
1204
1204
a
t
a
t
a
t
FIGS. 12A and 12B
It is further contemplated that the target element may be positioned between two of the positioning markers -, similar to target element described in relation to . Further, distance , may, in another example, not be equal to distance . In yet another example, the spacing between one or more of positioning markers -and/or positioning markers -may not be uniform. As such, the spacing may, in one example, be logarithmic, among others.
FIG. 14A
FIG. 14B
1400
1400
1402
1202
1302
1200
1300
1400
1404
1404
1404
1404
1204
1204
1304
1304
1200
1300
1400
1406
1206
1306
1400
1408
1408
1408
a
c
a
c
a
t
a
t
schematically depicts another implementation of a sizing device , according to one or more aspects described herein. Sizing device includes a base structure similar to base structures and described in relation to sizing devices and , respectively. Further, the sizing device includes a series of positioning markers, of which positioning markers -are an exemplary sub-set. These positioning markers -may be similar to positioning markers -and -described in relation to sizing devices and . The sizing device includes a target element , which may be similar to target element and/or target element , as previously described. The sizing device further includes a device deployment guide , which may be utilized by comparing the device deployment guide to a radiological image of a synthetic device (e.g. a stent, not depicted). The device deployment guide is further described in relation to .
FIG. 14B
FIG. 14A
FIG. 14B
FIG. 14B
1400
1402
1404
1404
1406
1408
1406
1408
1406
1408
1406
1408
a
c
schematically depicts a more detailed view of a portion of the sizing device from , according to one or more aspects described herein. In particular, schematically depicts a portion of the base structure , positioning markers -, target element , and a portion of the device deployment guide . In the depicted implementation of , the center of the target element is aligned with a centerline of the device deployment guide such that a user may utilize the target element to quickly determine a desired deployment diameter of the synthetic device (e.g. a stent) that the device deployment guide represents. It is contemplated, however, that the target element may not be aligned with a centerline of the device deployment guide , without departing from the scope of these disclosures.
1408
1404
1404
1406
1408
1408
1408
a
c
In one implementation, the device deployment guide may comprise one or more radiopaque materials, similar to the positioning markers -, and the target element . In one specific implementation, the device deployment guide may depict a pattern of one or more structures of a stent when expanded/deployed to a correct configuration. As such, the stent pattern depicted by the device deployment guide may be compared to a radiological image of a stent being inserted into a blood vessel of a patient. As such, when the pattern of the device deployment guide matches, or is within a range of, a received image of a deployed stent, a user may determine that the stent has been deployed to a correct configuration.
1408
1408
In one embodiment, the depicted image from the radiopaque materials is configured to depict a specific medical device, such as a stent. In one embodiment, a specific model of a stent may be depicted. A specific medical device (e.g., a stent) may have a specific pattern that is discernable in radiographic images when a placed in a specific arrangement, such as when correctly placed within a patient. For example, in one embodiment, element may depict a replica of properly placed Supera stent, commercially available from Abbott Laboratories, Abbott Park, Ill. In one embodiment, element may depict a stent or other device having an interwoven design such that the depicted element shows a pattern (which may be the overlaying pattern) when the device is correctly placed. Thus, when imaged, the pattern will be show the correct pattern in accordance with aspects herein. In one embodiment, the length of the depicted stent (or other depicted device) is to scale, such that a stent to be positioned within a blood vessel of a patient may be adjusted to match the depicted length, and thereby facilitate correct deployment.
1408
1408
In an alternative implementation, it is contemplated that the device deployment guide may include one or more images corresponding to one or more additional or alternative synthetic devices intended to be deployed within a biological feature (e.g. a blood vessel) of the patient. As such, the device deployment guide may depict a MEMS device, or a portion thereof, among others.
1200
1300
1400
500
601
812
1200
1300
1400
FIGS. 5A and 5B
FIGS. 6A and 6B
FIG. 8
FIGS. 15A-15B
The sizing devices , , and may be configured to be utilized in a similar manner to device described in relation to , device described in relation to , and/or device described in relation to . Accordingly, one or more of sizing devices , , and/or may be utilized during radiological imaging, as described in further detail in relation to .
FIG. 15A
FIG. 15A
FIG. 15A
1500
1502
1502
1200
1504
1506
1504
1506
1500
1200
1500
1502
1200
schematically depicts a first radiological image that includes an image of a sizing device , according to one or more aspects described herein. In one example, the image of the sizing device may be generated by utilizing the sizing device during radiological imaging, among others. further depicts a schematic view of a blood vessel and a branching blood vessel . It is contemplated that the blood vessels and are visible within the schematic first radiological image by introducing a contrast agent into the vessels while capturing one or more radiological images (e.g. x-rays, among others). As such, in the depicted schematic example of , a radiopaque portion of the sizing device appears within the image as sizing device image . As previously described, the sizing device may be utilized to, in one example, position a synthetic structure/device (e.g. a MEMS device) within a biological feature (e.g. a blood vessel) of a patient (it is contemplated that the systems and methods described herein may be utilized with human patients, as well as with animals, without break from the scope of these disclosures).
802
1502
1500
802
1206
1214
1504
1504
1508
1508
1204
1204
1508
1204
1204
1510
1204
1204
b
c
b
c
a
t
In one example, computer , may identify the sizing device image within the radiological image . In another embodiment, a user may facilitate the identification. Yet in another embodiment, the user may identify the image, such as to the computer . Further, the user and/or processes may identify the target element , and compare the size of the radiopaque ring to one or more portions of the blood vessel . A suitably-sized portion of blood vessel may be identified at position (it is contemplated that other criteria for blood vessel suitability may be utilized in addition to, or as an alternative to, blood vessel size, without departing from the scope of these disclosures). The location of position may be manually or automatically recorded relative to, in the depicted example, positioning markers and (e.g. the identified position may be identified as falling approximately halfway between positioning markers and , and at a distance away from the centerline of the series of positioning markers -).
1500
1508
1500
1508
In one implementation, it is contemplated that one or more processes may be executed to overlay digital graphics on the radiological image marking the location of position . In another example, a user may manually draw overlaid graphics (computer-generated or otherwise) on the radiological image marking the location of position .
FIG. 15A
1512
1512
1504
1512
1504
further schematically depicts a synthetic structure (e.g. a MEMS device ) that is being moved through the blood vessel and is in an un-deployed configuration. It is contemplated that the structure may be moved within the blood vessel using a catheter, or another device (not depicted), without departing from the scope of these disclosures.
FIG. 15B
FIG. 15A
FIG. 15B
FIG. 15A
FIG. 15A
1550
1550
1504
1506
1512
1508
schematically depicts a second radiological image of the same field of view from , according to one or more aspects described herein. Accordingly, schematically depicts the same area of the patient's body as , but since a contrast agent is not used while capturing the image data used to produce image , blood vessels and are not visible, or have reduced visibility. However, using the positioning information calculated from , the synthetic structure may be deployed at the selected position , as depicted.
FIG. 16
1600
1600
1500
802
1512
1600
1512
1512
1604
1512
1504
schematically depicts another implementation of a radiological image that may be produced according to one or more aspects described herein. In one example, the radiological image may be similar to radiological image . However, in one example, one or more processes may be executed by computer to identify a portion of the synthetic structure that is radiopaque and visible within the radiological image . Further, one or more processes may be executed to identify the model type of the synthetic structure , and overlay a computer-generated image that indicates a size of an additional portion of the synthetic structure that is not radiopaque. As such, element may represent a portion of the synthetic structure that extends beyond the radiopaque portion visible within a radiological image without a computer-generated overlay. As such, a user may utilize these one or more processes to display a true size of a synthetic structure as it is being delivered into, for example, a blood vessel of a patient.
FIG. 17
FIG. 8
FIGS. 12, 13, and 14
1700
800
1200
1300
1400
is a flowchart diagram of a process for identification of a suitable site within a biological feature of a patient for positioning of a synthetic structure, according to one or more aspects described herein. In one example, flowchart may be executed using the imaging system from , and one or more of the sizing devices , and/or from , respectively.
816
804
802
1702
1700
In one implementation, first radiological image data of an area of a body of a patient may be received. This first radiological image data may be generated during a time period when a radiopaque contrast agent is present in one or more biological features within the imaged area. These biological features may include, among others, tissues, organs, blood vessels, blood clots, and the like. In one embodiment, the radiological image data includes at least one vessel having a contrast agent present within at least a portion of a first vessel of the at least one vessel. The radiological image data may be received, from the detector , at the processor of computer device . These one or more processes to receive the first radiological image data may be executed at block of flowchart .
1200
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1400
804
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In one example, a radiopaque target element may be identified from the received first radiological image data. The target element may be generated by a sizing device, such as one or more of the sizing devices , and/or as electromagnetic radiation (e.g. x-rays) is passed through both the imaged area of the body of the patient, and the sizing device positioned on an area of skin of the patient. In one implementation, the radiopaque target element may be identified using one or more image recognition processes executed by the processor . Further, the radiopaque target element may be identified at block of flowchart .
The radiological image data may include images of one or more biological features within the imaged area of the patient's body. The identified radiopaque target element may be utilized to identify a specific location, portion, or entire feature itself that, as dictated by the captured radiologic data, has a dimensional property within an acceptable dimensional range. In one example, the biological feature may be a blood vessel, and the dimensional property may be a diameter of the blood vessel. Further, the target element may indicate a minimum and a maximum vessel diameter for a specific application (which may be mandatory, recommended, considered acceptable, and/or other criteria). In accordance with one aspect, the selected blood vessel (or location or portion thereof) may be identified to have a vessel diameter within the acceptable range between the minimum and maximum acceptable vessel diameters based upon a comparison with the target element as captured by the imaging data.
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Accordingly, one or more processes may be executed to identify, from the radiopaque target element, the acceptable dimensional range, and compare it to one or more biological features within the first radiological image data. Further, the one or more processes may identify one or more portions of a biological feature (e.g. one or more sections of a blood vessel of a patient) within the acceptable dimensional range indicated by the radiopaque target element. It is contemplated that additional or alternative criteria may be utilized to identify the biological feature, or a portion thereof. These additional or alternative criteria may include, among others, a length and/or a straightness of the biological feature. It is further contemplated that the radiopaque target element may be compared to the one or more biological features to manually identify a biological feature with a dimensional property within an acceptable dimensional range. Accordingly, one or more manual tools may be utilized. For example, a calipers may be utilized to mark a vessel diameter within the acceptable dimensional range, and compare this marked vessel diameter to one or more portions of blood vessels imaged within the first radiological image data. One or more processes to identify the biological feature, from one or more biological features within the received first radiological image data, may be executed at block of flowchart .
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A target location of the identified biological feature may be determined relative to one or more radiopaque positioning markers of a sizing device, such as one or more of the sizing devices , and/or , as previously described. In one example, an x- and y-coordinate of a target location of the identified biological feature may be determined. It is contemplated, however, that additional or alternative coordinate systems may be utilized, without departing from the scope of these disclosures. In one example, the target location of the identified biological feature may be calculated by a processor, such as connected to computer , and may be communicated to a user as a computer-generated graphical overlay on a radiological image output from, in one example, the user interface . In another example, the target location of the identified biological feature may be manually identified by noting a position of the target location relative to one or more of the positioning markers of the sizing device (in addition to the target element serving as a guide for which location of one or more features (or portions thereof) are suitable for receiving the medical device and/or selecting a specific medical device, model of device, or medical device with specific dimensional properties (e.g., diameter). This manual identification may utilize one or more manual tools (e.g. a calipers may be utilized to determine the position of the target location relative to one or more of the radiopaque positioning markers. These one or more processes may be executed at block of flowchart .
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Second radiological image data may be received, such as by the processor . The second radiological image data may correspond to the same area of the body of the patient as the first radiological image data. However, the second radiological image data may be captured during a time period when the contrast agent is not present within one or more biological features within the imaged area. As such, in one example, the generated radiological image may not include one or more blood vessels previously visible within the first radiological image described in relation to block . In one implementation, one or more processes may be executed to receive the second radiological image data at block of flowchart . In this regard, aspects of this disclosure relate to using reduced contrast agent quantities when compared to prior art systems and methods.
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A synthetic structure, or a radiopaque portion thereof, may be identified within the received second radiological image data. Accordingly, one or more image recognition processes may be executed to identify the synthetic structure within the second radiological image data. In another example, a user may manually identify the synthetic structure within a second radiological image communicated to the user by the user interface . The synthetic structure may comprise, among others, a MEMS device, or a stent, and may be configured to be positioned within the biological feature at the identified target location. One or more processes to identify the synthetic structure to be positioned at the target location of the identified biological feature may be executed at block of flowchart .
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Optionally, one or more processes may be executed to generate an augmented image of the identified synthetic structure. The augmented image may comprise a computer-generated graphical overlay on top of a radiological image that is communicated to the user through the user interface . As such, one or more image recognition processes may be utilized to identify a visible portion of the synthetic structure within radiological image data. This visible portion may correspond to a radiopaque portion of the synthetic structure. Further, upon identification of the radiopaque portion of the synthetic structure, a stored description of the synthetic structure may be utilized to identify and generate the graphical overlay that represents at least a portion of the synthetic structure that is radiolucent/radio translucent, and not readily visible within radiological image data. As such, these one or more processes may be executed to generate an augmented image of the synthetic structure that includes a radiolucent portion at block of flowchart .
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A location of the identified synthetic structure relative to the target location may be determined. As such, a user may utilize this information to move the synthetic structure to the target location without, or with reduced, contrast agent being introduced into one or more biological features of a patient. One or more processes to determine the location of the synthetic structure relative to the target location may be executed at block of flowchart .
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An output may be communicated to a user when the synthetic structure is within a threshold distance of the target location. It is contemplated that the output may comprise a visual, an audible, or a haptic feedback signal that is communicated to the user through the user interface . It is further contemplated that the threshold distance may include any distance value, without departing from the scope of these disclosures. Accordingly, one or more processes to communicate the output to the user when the synthetic structure is within the threshold distance may be executed at block of flowchart .
The various embodiments described herein may be implemented by general-purpose or specialized computer hardware. In one example, the computer hardware may comprise one or more processors, otherwise referred to as microprocessors, having one or more processing cores configured to allow for parallel processing/execution of instructions. As such, the various disclosures described herein may be implemented as software coding, wherein those of skill in the computer arts will recognize various coding languages that may be employed with the disclosures described herein. Additionally, the disclosures described herein may be utilized in the implementation of application-specific integrated circuits (ASICs), or in the implementation of various electronic components comprising conventional electronic circuits (otherwise referred to as off-the-shelf components). Furthermore, those of ordinary skill in the art will understand that the various descriptions included in this disclosure may be implemented as data signals communicated using a variety of different technologies and processes. For example, the descriptions of the various disclosures described herein may be understood as comprising one or more streams of data signals, data instructions, or requests, and physically communicated as bits or symbols represented by differing voltage levels, currents, electromagnetic waves, magnetic fields, optical fields, or combinations thereof.
One or more of the disclosures described herein may comprise a computer program product having computer-readable medium/media with instructions stored thereon/therein that, when executed by a processor, are configured to perform one or more methods, techniques, systems, or embodiments described herein. As such, the instructions stored on the computer-readable media may comprise actions to be executed for performing various steps of the methods, techniques, systems, or embodiments described herein. Furthermore, the computer-readable medium/media may comprise a storage medium with instructions configured to be processed by a computing device, and specifically a processor associated with a computing device. As such the computer-readable medium may include a form of persistent or volatile memory such as a hard disk drive (HDD), a solid state drive (SSD), an optical disk (CD-ROMs, DVDs), tape drives, floppy disk, ROM, RAM, EPROM, EEPROM, DRAM, VRAM, flash memory, RAID devices, remote data storage (cloud storage, and the like), or any other media type or storage device suitable for storing data thereon/therein. Additionally, combinations of different storage media types may be implemented into a hybrid storage device. In one implementation, a first storage medium may be prioritized over a second storage medium, such that different workloads may be implemented by storage media of different priorities.
Further, the computer-readable media may store software code/instructions configured to control one or more of a general-purpose, or a specialized computer. Said software may be utilized to facilitate interface between a human user and a computing device, and wherein said software may include device drivers, operating systems, and applications. As such, the computer-readable media may store software code/instructions configured to perform one or more implementations described herein.
Those of ordinary skill in the art will understand that the various illustrative logical blocks, modules, circuits, techniques, or method steps of those implementations described herein may be implemented as electronic hardware devices, computer software, or combinations thereof. As such, various illustrative modules/components have been described throughout this disclosure in terms of general functionality, wherein one of ordinary skill in the art will understand that the described disclosures may be implemented as hardware, software, or combinations of both.
The one or more implementations described throughout this disclosure may utilize logical blocks, modules, and circuits that may be implemented or performed with a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
The techniques or steps of a method described in connection with the embodiments disclosed herein may be embodied directly in hardware, in software executed by a processor, or in a combination of the two. In some embodiments, any software module, software layer, or thread described herein may comprise an engine comprising firmware or software and hardware configured to perform embodiments described herein. Functions of a software module or software layer described herein may be embodied directly in hardware, or embodied as software executed by a processor, or embodied as a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read data from, and write data to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user device. In the alternative, the processor and the storage medium may reside as discrete components in a user device.
Accordingly, it will be understood that the disclosure is not to be limited to the embodiments disclosed herein, but is to be understood from the following claims, which are to be interpreted as broadly as allowed under the law. | |
Abstract: Three clones of black poplar and a hybrid poplar clone, “NE-42”, were trialled in a short rotation coppice system. The trial was replicated in three sites located in the Czech Republic with distinctly different soils and climates which were judged to be respectively favorable, unfavorable and marginal for growing black poplar. In the marginal and unfavorable sites the planting density was 2222 trees ha-1 and in optimal conditions 7407 trees ha-1. The aim of the trial was: (1) to test the performance of black poplar clones as a possible replacement for commercial hybrid poplars in areas where the genetic integrity of wild black poplar populations is under threat; (2) to test the range of conditions in which it is possible to grow black poplar and its suitability for utilizing marginal agricultural land; and (3) to measure the potential yield of black poplar clones grown in these conditions. During four harvests at three-year intervals, the following parameters were measured: plant mortality, number of shoots, thickness of shoots, the total cross-sectional area (TCA) of all shoots, the dry matter weight of individual plants (DMIP) and the dry matter yields per hectare. The differences observed between “NE-42” and the best black poplar clone decreased as conditions became more favorable. During the fourth harvest at the unfavorable site for growing poplars, the yield of dry biomass was 11.7 t ha-1 yr-1 for “NE-42” compared to 3.7 t ha-1 yr-1 for the best black poplar clone. In marginal conditions the yields were 11.8 and 9.9 t ha-1 yr-1 respectively, and in the favorable conditions there was no statistically significant difference, being 15.9 and 13.2 t ha-1 yr-1, respectively. The higher yield of “NE-42” was due to the higher proportion of thicker shoots or, alternatively, lower plant mortality. The observed TCA was highly correlated with DMIP (rs = 0.87) and dry biomass yield (rs = 0.48). It was demonstrated that black poplar can be successfully grown in marginal conditions on land which otherwise would not be especially suitable for agricultural production, and also in areas where the genetic purity of native populations of black poplar is threatened by the spread of commercially grown hybrid poplars.
The cultivation of fast-growing trees in short rotation coppice (SRC) systems has increased in recent years mainly because it provides a source of renewable energy. Today such kind of farming covers thousands of hectares in Europe (, ), with the most commonly grown species being willows (Salix) and poplars (Populus - , , ). This trend has also been accompanied by extensive plant breeding (, ), but the selection of new cultivars has been based almost entirely on inter-specific crosses. In Europe new poplar hybrids are derived mainly from crosses between P. nigra and P. deltoides Bart. ex Marsh. () or P. nigra and P. maximowiczii Henry (). Such hybrids are capable of successfully pollinating and breeding with wild populations of P. nigra, and consequently are a threat to the genetic purity of this indigenous species (, , ). The spread of these hybrids and the contamination of P. nigra gene pools has lead in certain places to restrictions being placed on their cultivation. This raises the question if it is possible or not to develop commercially acceptable clones of pure-bred black poplars to grow in place of the undesirable interspecific hybrids. According to several published results, many clones derived from genetically pure species of the genus Populus show yields comparable with the inter-specific hybrid clones. In trials with the species P. trichocarpa Torr. & Gray, the pure species had similar yields to the hybrids (). In other trials using P. nigra and P. trichocarpa, their biomass yields over four successive harvests were remarkably higher than in hybrid clones such as P. trichocarpa × P. deltoides and P. deltoides × P. trichocarpa ().
Species of the genus Populus and their hybrids can be regarded as having two main different strategies for biomass formation as for the number of shoots per plant. The first group includes P. trichocarpa and P. trichocarpa × P. deltoides, which eliminate small shoots rapidly to leave just a few large dominant shoots. The second group, comprising genotypes like P. nigra and P. trichocarpa× P. balsamifera L., eliminate small shoots slowly, so maintaining many small shoots per stool (, ). Furthermore, differences in the proportion of lateral shoots contributing to yield in P. nigra and hybrid clones have been observed as early as in the second and third harvests, when the proportion of lateral shoots can be significant (, ). In situations where there is a lower overall number of shoots it can be expected that these will be thicker. Moreover, after each harvest there is an increase in the number of shoots per plant (, , ) and therefore the resource demands on the site will also increase, boosting the intra-specific plant competition. However, this is off-set by the reduction of plant shoots or even plant numbers due to pathogens, shading or increased competition for resources (the self-thinning effect), which then opens up the area to be better utilized by the remaining plants (). The number of plants per unit area after the first and second rotations can be significantly reduced by plant mortality (, ). Large differences in mortality among the studied genotypes have been observed in experiments conducted over several rotations (, ).
SRC systems are a long-term culture which may last for up to 25 years (). The expression of the various yield traits, which together contribute to the final yield of biomass, is dependent on the interaction of any given genotype and its environment. It is therefore important to evaluate the performance of genotypes in the different conditions in which they will be grown. The main environmental factors to consider are levels of available light, water and soil fertility.
P. nigra is the principal pioneer tree species that colonizes river floodplains, wastelands and other exposed sites, where the moist, sandy soil exposed after seasonal flooding provides an ideal seedbed (). Based on an analysis of ecological requirements of P. nigra, optimal conditions for its growth in the Czech Republic would be provided by sites with an average annual temperature of 7.5 to 9.0 °C, a temperature in the growing season (April to September) above 14 °C, with hydromorphic or semi-hydromorphic soils and a water table at a depth of 0.5 to 1.2 m, or at a depth of only 1.0 m where dense vegetation prevents the full penetration of rain water. Heavy clay soils are unsuitable. Colder locations are less favorable, and those with an annual average temperature below 6 °C and temperatures during the growing season below 12 °C are unsuitable (). However in Italy, for example, optimal conditions for hybrid poplar cultivation are a mean annual temperature of 8.5 to 17 °C and a summer precipitation of 100-150 mm ().
Fast-growing trees in SRC systems are predominantly grown in areas of intensive agriculture. This lead to a competition between the production of food and other agricultural commodities on the one hand, and the production of biomass from fast-growing trees on the other. Trees can also be grown in conditions which are marginal for conventional agricultural activities, but perhaps the real question here is whether they can still achieve satisfactory yields in such conditions.
The aim of this study was to appraise the individual yield parameters contributing to the total yield of biomass, and compare the biomass yields of several clones of black poplar with that of the hybrid clone “NE-42”, when grown in three distinctly different environments for a total of four rotations. Further, to determine the environments in which black poplar can be successfully established and grown.
The experiment was established in three sites in the Czech Republic, each with different soil and climatic conditions (Tab. 1). The first site (Smilkov - SM) represents natural conditions which can be regarded as marginal but typical for the main areas where SRC systems are used. The second site (Bystrice - BY) is located in unfavorable soil and climate conditions. After a four year delay, the third trial (Rosice - RO) was established in optimal soil and climate conditions typical for a flood plain ecosystem and therefore most favorable. Compared to the other two localities, trees were established here using more dense plantings.
Tab. 1 - Description of the study localities.
Four clones of P. nigra (designated 107, 210, 301 and 302), of the total of 29 included in a wider trial, can be found growing in all three trial localities. These clones are the offspring of individuals found in local sub-populations (). The first three clones of P. nigra (107, 210, 301) have already been shown to be healthy and possessing good yield potential, and have been recommended for cultivation in the Czech Republic (). Clone 302, on the other hand, is regarded as being one of the least productive. Clone “NE-42”, an interspecific hybrid of P. maximowiczii × P. trichocarpa, was used as a control.
Densities of 2222 plants ha-1, with a spacing of 3 × 1.5 m, were employed in the less favorable (SM) and the unfavorable (BY) localities; in the RO site (favorable conditions) the planting density was increased to 7407 plants ha-1, with a tighter spacing of 2 × 0.67 m. Plant densities were chosen with regard to the soil and climatic characteristics of these three localities (Tab. 1). Rainfall during the growing season (months IV-IX) was only measured at the SM site. In the localities BY and RO a crucial role was played by groundwater.
The experiment was established in 1998 at the SM and BY sites, while the RO site was planted in 2002. A randomized block design with four replications was used, with four plants of each clone per replication in the BY locality and with five plants per replication in the SM site. In the RO locality the experiment had five replications with six plants per replication. Bordering rows were planted around each experimental plot. The plots were also fenced to prevent browsing by wild animals.
The planting material was obtained by cultivating 0.2 m-long hardwood cuttings, 5 to 6 mm in thickness; the resulting one-year old saplings were planted out manually, with those planted at the SM site being watered in. Using one-year old saplings, the planting densities at the beginning of the experiment were the same for each investigated clone at any given site. All plants were clipped to a height of 0.4 m after planting out. The SM site was also always fertilized after harvest, with an NPK (1:1:1) growth fertilizer at a rate of 150 kg ha-1, and a herbicide applied in the spring following each harvest. Twice each summer the weeds were cut and the soil disced between the rows. At the BY and RO sites discing was omitted.
The first harvest at the BY and SM sites was carried out in February 2001, the second harvest was in March 2005, the third in March 2008 and the fourth in March 2011. At the RO site the first harvest was carried out in February 2005, the second in February 2007, the third in March 2010 and the fourth in January 2013. Plants were pruned by hand to a height of 0.1 m above the ground for the first harvest, but in subsequent harvests they were pruned to 0.2 m above the ground.
At the end of each growing season before harvesting, growth was measured by taking the diameter of each main stem at a height of 0.5 m from the ground. Before the second, third and fourth harvests, all shoots thicker than 0.01 m were counted and their diameters measured using a digital caliper. Shoots were classified on the basis of their diameter as being “weak” (10-43 mm) or “strong” (44-95 mm). The shoot with the highest diameter was considered as a main stem. Before the fourth harvest the combined total cross-sectional area of all measured shoots (TCA) was calculated and expressed as the sum total area in mm2 per plant. The TCA per 100 m2, which also indirectly took account of plant mortality, was expressed in m2.
During harvest the fresh weight biomass produced jointly from all the plants of a given clone in each replicate was weighed. To measure dry weights at the same time, a representative sample of the harvested material, including the main and lateral shoots, was taken from each replicate and weighed separately. The size of these samples ranged from 400 to 1200 g, depending on the thickness of the shoots. The samples were dried at 105 °C until their weights stabilized. Total dry matter yields per unit area were calculated from the weight of harvested fresh biomass obtained from a given replicate multiplied by the appropriate value for the per cent dry matter and calculated for a given unit area (ha) per year. Yield is a function of the number of plants actually harvested and takes the plant mortality into account. The average dry matter weights of individual plant (DMIP) were expressed in kg yr-1.
The analysis of variance (ANOVA, MANOVA) or its non-parametric homologous tests was carried out using the Statistica 8.0 statistical software package (StatSoft Inc., Tulsa, OK, USA). Clones, replicates, localities and rotations were used as independent variables, and parameters such as total dry matter yields per unit area, DMIP, number of shoots per plant, TCA, and diameters of the strongest shoots were used as dependent variables. When a statistical difference was found, a post-hoc comparison was carried out using Duncan’s test or multiple comparisons of mean ranks. Significant differences between individual rotations or localities were established on the basis of t-tests. Spearman’s coefficient of rank correlation was calculated between TCA and the parameters DMIP and total biomass production. All the results are presented using a significance level of α = 0.05.
Since some of the results based on the first two harvests have already been published elsewhere (), the results presented here are mainly those derived from the third and fourth harvests. Significantly different performances of the clones in each of the three different localities was confirmed during the fourth harvest for each of the variables considered, with the exception of the dry matter yields per unit area.
The number of shoots and plants per unit area fell during the course of the four rotations, and significantly differed among sites and clones (Tab. 2).
Tab. 2 - Percentage of surviving plants in each site before harvests.
At the locality with marginally suitable soils and climatic conditions (SM), and with less dense vegetation, mortality of clones was low (0-5%), and such losses were the result of mechanical damage incurred during the year of planting. Only for clone 302, which has been shown to be unsuitable for growing in SRC, losses were high, reaching 20%. There were no significant differences between “NE-42” and the black poplar clones.
In locality BY mortality of clone “NE-42” was lower (6%), though not statistically significant. Before the fourth harvest mortality in the black poplar clones ranged from 19 to 50%, although in clone 302 it was 94%. The high losses were the result of unsuitable soils and climate.
In the locality RO (with dense vegetation), losses were observed for all clones, and by the time of the fourth harvest, mortality in the black poplar clones ranged from 40 to 90%. In “NE-42” the mortality was 36%. An increase in mortality was always observed after harvest, and was particularly significant after the third harvest (Tab. 3). At this time, the surviving plants completely shaded the ground. The dead tree stumps were also infected by Cylindrocarpon, Fusarium and Verticillium fungi (Pešková & Soukup, personal communication), which in certain circumstances can act as facultative parasites, invading weakened plants.
Tab. 3 - A comparison of successive harvests in clones of black poplar and “NE-42” in each locality (t-tests). (*): significant differences (p<0.05).
Clone 302 was dropped from subsequent assessments due to the unacceptably high mortality observed in all sites.
The number of shoots per plant was always higher in the black poplar clones compared to “NE-42” before harvest in each locality but only statistically significantly higher in the SM locality, before the second, third and fourth harvests. In locality BY, with less suitable conditions, the average number of shoots was significantly lower than in SM. In the locality RO the number of shoots before the second harvest was low and increased very slowly in following harvests (Tab. 4).
Tab. 4 - Four yield traits and differences among clones before the fourth harvest. (N): number of observations.
The number of shoots developed after the third harvest in locality SM was roughly double compared to the BY site (Tab. 5). In the interval between the third and fourth harvests the number of shoots in SM and BY was reduced by a third, and in RO by half, although in locality BY the temperature and soil conditions were less favorable than RO with similar soil-water availability. As a result of the higher planting density the light conditions were worse in locality RO, which probably had an influence on the production of a lower number of shoots and their higher mortality.
Tab. 5 - Mortality of shoots during the forth rotation with respect to the dead plants.
The results show that the plants are able to utilize a larger area for the formation of a higher number of shoots, especially in P. nigra.
Leading shoot diameter before the first harvest correlated with the quality of natural conditions in P. nigra (Fig. 1b). During the fourth harvest in locality BY with sufficient ground water but unfavorable soil and temperature conditions, the leading shoot diameter was significantly greater in “NE-42” compared to the black poplar clones. Also, in the site SM with less available ground water and average rainfall but with higher levels of nutrients (see Tab. 1), the differences between “NE-42” and the black poplar clones were significant. In locality RO with accessible ground water, higher temperatures and fertile soils, the leading shoot diameter in “NE-42” was the same as the black poplar clones (Tab. 4).
Fig. 1 - Time course of stool survival rate (a), diameter of the strongest shoot (b), dry matter weight of individual plants (c) and total dry matter yield per unit area (d) over the four rotations of the coppiced the best P. nigra clone 107 (triangle) and “NE-42” (square) in SM (continuous line) and RO site (dotted line).
The average shoot diameter was 30.4 mm in RO, where the number of shoots was lower, 25.9 mm in BY and 21.4 mm in SM, where the number of shoots was higher.
The proportion of stronger shoots in any given locality was always lower in black poplar (based on average values for the three clones) compared to “NE-42” (Tab. 6), although in the most favorable soils and temperatures the differences were reduced. This shoot diameter difference is also related to the yield parameters.
Tab. 6 - Percentage of weak (diameter 10-43 mm) and strong shoots (44-95 mm) per clone in each locality. (∅): diameter [mm].
The TCA of all shoots was measured before the fourth harvest (Tab. 4). In locality BY there was a significantly higher average TCA in “NE-42” (15.677 mm2) than in the black poplar clone 210 (5.466 mm2), while in SM the average TCA values in all clones were similar, ranging from 14.063 to 15.974 mm2. In RO the best black poplar clone, 107, had an average TCA value of 7.042 mm2 and “NE-42” had an average TCA of 5.878 mm2. Just as with the leading shoot diameter, in unfavorable conditions of soil and temperature in the presence of adequate water, “NE-42” performed better than black poplar regarding TCA. Using Spearman’s coefficient of rank correlation the very strong positive correlation of TCA and DMIP (rs = 0.871, p < 0.001) and moderate positive correlation of TCA and dry matter yield (rs = 0.475, p = 0.001) was confirmed.
In the locality RO, the DMIP increased almost linearly among harvests (Fig. 1c) and the increment between first and second harvest was significant in almost all clones (Tab. 3). No difference in DMIP was found among all clones in any harvest (Tab. 7). When comparing localities SM and BY after the first harvest, non-significantly higher average values for DMIP were found in all clones at the locality SM with exception of “NE-42”. During the second and subsequent harvests, significantly higher average values were found in the locality SM compared to BY in all black poplar clones. By the fourth harvest, the DMIP of black polar clones in SM was twofold higher than in BY. However, the DMIP of the best black poplar clone in each locality was only significantly lower than “NE-42” for the second and fourth harvests at the BY site.
Tab. 7 - Dry matter weight of individual plants [kg yr-1] for each harvest.
“NE-42” gave the highest biomass yields in each of the four harvests in each of the three sites (Tab. 8). During the fourth harvest the difference in biomass produced by “NE-42” and the best black poplar clone was significant in sites BY and SM. However, in locality RO the yield from clone 107 during the fourth harvest was not significantly different, being 13.2 t ha-1 yr-1 compared to 15.9 t ha-1 yr-1. In the locality BY the black poplar yields were low and showed no significant differences in growth from the the second to the fourth harvest (Tab. 3). In the SM site yields from the second harvest onwards were significantly greater and gradually increased over time, even though the differences were not statistically significant. Only in clone 107 was the yield significantly increased from the second to the third harvest in SM and RO (Tab. 3). In this clone, as in “NE-42”, the strong shoots made up a significant proportion of the TCA. In “NE-42” after the second harvest biomass did not significantly increase. During the first two harvests in RO the yields of all clones were much higher than in the other two locations, which can be explained by the higher initial planting densities and, during the first harvest, also the higher individual plant weights. In subsequent harvests the yields increased less rapidly and during the fourth harvest in all clones yields actually fell (Fig. 1d), due to high mortality.
Tab. 8 - Total dry matter yields per unit area [t ha-1 yr-1] in black poplar clones and in the hybrid clone “NE-42”; expressed with respect to the percentage of surviving plants.
The interaction of environmental conditions on yield traits and biomass produced by black poplar compared to the hybrid clone “NE-42” was evaluated at three localities. Differing natural conditions in these sites allowed the study of a wide range of reactions of the individual genotypes. Two localities represented marginal areas in the distribution of black poplar, where the planting of allochthonous species is usually not allowed (e.g., national parks). In these situations it is anticipated that only pure clones of black poplar will be grown in SRC systems. The third locality represents flood plain areas which are suitable for growing black poplar because it is tolerant of long-term flooding ().
The hybrid “NE-42” showed higher yield than the most productive black poplar clone in all three environments. It must be said, however, that this hybrid clone is the result of a selection process involving several thousand seedlings derived from planned crossings (), while the black poplar clones were chosen from a group of 200 individuals collected from wild populations (). However, several new clones of black poplar now exist which are the result of deliberate crossings, and in early trials have given higher yields than “NE-42” (), so black poplar clones with satisfactory yield potential are expected to be available soon.
In the locality with a low average temperature and low pH, and nutrient-poor peaty soils (BY), the black poplar clones had low yields, while “NE-42” achieved yields comparable to those in locality SM with its medium quality soils and higher average annual temperatures. In these more favorable conditions the yields of the best black poplar clones approached those of “NE-42”. In the most favorable conditions (locality RO), there was no significant difference between the yields of the best black poplar clones and the hybrid. This means that black poplar did not perform well only in the very unfavorable conditions regarding soils and temperatures, while “NE-42” demonstrated greater adaptability and performed well even under unfavorable conditions. It would appear that here the character of one of the parent species (Populus trichocarpa) is being expressed ().
Total yields per unit area are determined by the number of plants per unit area and the weight of individual plants. The initial numbers of plants falls over time due to mortality, although observed mortality was lower than in stands with higher initial plant densities (). The effect of varying initial plant densities on subsequent mortality was observed in our experiment also.
The weight of individual plants is positively correlated with various component parameters such as height, thickness and the number of shoots (, , ). As has been shown, height is correlated with thickness of the main stem (), and so only one of these parameters needs to be measured in order to estimate yields. Differences in the thickness of stems between “NE-42” and the black poplar clones was less pronounced in the more favorable growing conditions. The number of shoots increased during the four harvests in this study, although the number of shoots regenerating from the cut stumps also depends on the amount of light, which is in turn affected by plant density (). Competition between shoots for light during canopy closure is believed to affect stool survival (). The poplar genotypes differ with regard to their light-use efficiency and so also in the extent to which their photosynthesis is optimized in dense canopies ().
Even though the weight of individual plants was great in locality SM, the amount of biomass yield per hectare was not corresponding with it. The maximum yield of biomass was probably limited here by the overall low density of plants, as reported by Enquist et al. () and Weiner & Freckleton ().
In comparing the yield potential of the hybrid “NE-42” and the best black poplar clones used in these trials, it can be supposed that black poplar can be successfully grown even in marginal areas for the natural occurrence of black poplar, that is, in areas with low average temperatures and less fertile soils, but not however in areas with low temperatures and peaty soils (), where the hybrid clone “NE-42” is more successful.
The TCA measured just before the fourth harvest was highly correlated with DMIP and also correlated with the yield of biomass on individual plots. As early as the second harvest a correlation was confirmed between the number of shoots and also the thickness of the main shoot and biomass yields (). The correlation between the height of plants, thickness of shoots and other parameters and biomass yields is well-known from many studies and has been used for the non-destructive estimation of total biomass (, ). These correlations could be used to estimate DMIP and biomass yields during the selection process in breeding programs, when the first selection is made on the basis of visual assessments. However, breeding programs must also take into account resistance to important diseases, principally the leaf rust Melampsora larici-populina, which can significantly lower final yields () with its damaging effects on plant growth (), affecting the amount of light penetrating the canopy and so the competition among plants.
It can be concluded that in the selection of new black poplar clones it is important to consider the genotypes which produce thick, strong shoots rather than large numbers of weaker shoots, even though black poplar yields tend to be based on the production of large numbers of weaker shoots (). The possibility of successfully making such a selection in black poplar is confirmed by the marked genetic diversity evident in the number and strength of its shoots ().
The three best black poplar clones planted in three different sites had in all four harvests a lower yield than the hybrid clone “NE-42” which was used as a standard for comparison. These differences were less marked in the locality with better natural growing conditions and were not significantly different at the site with the most favorable growing conditions. The higher yield of the hybrid clone is evidently related to the fact that it has been produced by selecting from the progeny of an interspecific cross, in which the aim was to take advantage of the phenomenon of hybrid vigor. The black poplar clones, however, were derived by taking material from a wild population and were not the product of any kind of selective breeding program. These clones showed less adaptability to unfavorable temperature and soil conditions compared to “NE-42”, whose greater adaptability can be attributed to the characteristics of one of its parent species, P. trichocarpa.
A clear correlation was shown between the total cross-sectional area of shoots on the one hand and the dry weight of individual plants and the dry weight of harvested biomass on the other. This relationship could prove useful when making the first selection in any breeding program designed to produce higher performing clones of black poplar.
This research was financially supported by project no. 2B06131 of the Czech Ministry of Education, Youth and Sports and institutional support (VUKOZ-IP-00027073). The authors gratefully acknowledge the help provided by Malcolm Russell with the English.
Atwood CJ, Fox TR, Loftis DL (2008). Stump sprouting of oak species in three silvicultural treatments in the southern Appalachians. In: Proceedings of the “16th Central Hardwoods Forest Conference” (Jacobs DF, Michler CH eds). West Lafayette (Indiana, USA) 8-9 April 2008, pp. 2-7.
Benetka V, Vacková K, Bartáková I, Pospíšková M, Rasl M (2002). Introgression in black poplar (Populus nigra L. ssp. nigra) and its transmission. Journal of Forest Science 48: 115-120.
Benetka V, Vrátný F, Šálková I (2007). Comparison of the productivity of Populus nigra L. with an interspecific hybrid in a short rotation coppice in marginal areas. Biomass and Bioenergy 31: 367-374.
Benetka V, Cerný K, Pilarová P, Kozlíková K (2011a). Effect of Melampsora larici-populina on growth and biomass yield of eight clones of Populus nigra. Journal of Forest Science 57: 41-49.
Benetka V, Kozlíková K, Štochlová P (2011b). New clones of black poplar (Populus nigra L.) for short station coppice cultures. Acta Pruhoniciana 97: 33-38. [in Czech].
Benetka V, Novotná K, Štochlová P (2012). Wild populations as a source of germplasm for black poplar (Populus nigra L.) breeding programmes. Tree Genetics and Genomes 8: 1073-1084.
Bisoffi S, Gullberg U (1996). Poplar breeding and selecion strategies. In: “Biology of Populus and its implications for management and conservation” (Stettler RF, Bradshaw Jr HD, Heilman PE, Hinckley TM eds). NRC Research Press, National Research Council of Canada, Ottawa, ON, Canada, pp. 139-158.
Cagelli L, Lefèvre F (1995). The conservation of Populus nigra L. and gene flow with cultivated poplars in Europe. Forest Genetics 2: 135-144.
Dickmann DI, Kuzovkina J (2008). Poplars and willows in the World. Chapter 2, Working paper IPC/9-2, FAO, Rome, Italy, pp. 134.
Dillen SY, Vanbeveren S, Al Afas N, Laureysens I, Croes S, Ceulemans R (2011). Biomass production in a 15-year-old poplar short-rotation coppice culture in Belgium. In: “Aspects of Applied Biology 112: Biomass and Energy Crops IV”. Association of Applied Biologists, Wellesbourne, UK, pp. 99-106.
Enquist BJ, West GB, Brown JH (2009). Extensions and evaluations of a general quantitative theory of forest structure and dynamics. Proceedings of the National Academy of Sciences USA 106: 7046-7051.
Felix E, Tilley DR, Felton G, Flamino E (2008). Biomass production of hybrid poplar (Populus spp.) grown on deep-trenched municipal biosolids. Ecological Engineering 33: 8-14.
Green DS, Kruger EL, Stanosz GR, Isebands JG (2001). Light-use efficiency of native and hybrid poplar genotypes at high levels of intracanopy competition. Canadian Journal of Forest Research 31: 1030-1037.
Karp A, Hanley SJ, Trybush SO, Macalpine W, Pei M, Shield I (2011). Genetic improvement of willow for bioenergy and biofuels. Journal of Integrative Plant Biology 53: 151-165.
Langeveld H, Quist-Wessel F, Dimitriou I, Aronsson P, Baum C, Schulz U, Bolte A, Baum S, Köhn J, Weih M, Gruss H, Leinweber P, Lamersdorf N, Schmidt-Walter P, Berndes G (2012). Assessing environmental impact of short station coppice (SRC) expansion: model definition and preliminary results. Bioenergy Research 5: 621-635.
Laureysens I, Pellis A, Willems J, Ceulemans R (2005). Growth and production of a short rotation coppice culture of poplar. III. Second rotation results. Biomass and Bioenergy 29: 10-21.
Nelson ND, Burk T, Isebrans JG (1981). Crown architecture of short-rotation, intensively cultured Populus. I. Effects of clone and spacing on first-order branch characteristics. Canadian Journal of Forest Research 11: 73-81.
Pontailler JY, Ceulemans R, Guittet J, Mau F (1997). Linear and non-linear functions of volume index to estimate woody biomass in high density young poplar stands. Annals of Forest Science 54: 335-345.
Rogers DL, Stettler RF (1989). Genetic variation and productivity of Populus trichocarpa and its hybrids. III. Structure and pattern of variation in a 3-year field test. Canadian Journal of Forest Research 17: 415-425.
Smith JHG (1957). Some factors indicative of site quality for Black Cottonwood (Populus trichocarpa Torr. and Gray). Journal of Forestry 55: 578-580.
Smulders MJM, Beringen R, Volosyanchuk R, Van den Broeck A, Van der Schoot J, Arens P, Vosman B (2008). Natural hybridisation between Populus nigra L. and P. × canadensis Moench. Hybrid offspring competes for niches along the Rhine river in the Netherlands. Tree Genetics and Genomes 4: 663-675.
Stanton BJ, Neale DB, Li S (2010). Populus breeding: from the classical to the genomic approach. In: “Genetics and Genomics of Populus” (Jansson S, Bhalerao RP, Groover AT eds). Plant Genetics and Genomics: Crops and Models, Springer Science + Business Media, vol. 8, pp. 309-342.
Strong T (1989). Rotation length and repeated harvesting influence Populus coppice production. Research Note NC-350, North Central Experimental Station, USDA Forest Service, St. Paul, MN, USA, pp. 1-4.
Stout AB, Schreiner EJ (1933). Results of a project in hybridizing poplars. Journal of Heredity 24: 216-229.
Venendaal R, Jørgensen U, Foster CA (1997). European energy crops: a synthesis. Biomass and bioenergy 13: 147-185.
Verwijst T (2001). Willows: an underestimated resource for environment and society. Forestry Chronicle 77: 281-285.
Weiner J, Freckleton RP (2010). Constant final yield. Annual Review of Ecology, Evolution, and Systematics 41: 173-192. | http://www.sisef.it/iforest/contents/?id=ifor1162-007 |
Objective: To evaluate the efficacy of artificial neural networks in categorizing pediatric trauma patients into four distinct acuity of care groups and in determining the length of stay (LOS) within specific areas of the hospital.
Design: Using historical information from > 8,000 pediatric trauma patient records, train and evaluate artificial neural networks to predict the injury severity and LOS for each patient in pediatric intensive care units (PICUs), step-down units, and floor units. Each artificial neural network is evaluated for categorization accuracy and mean absolute error difference on the predicted LOS.
Subjects: A total of 10,353 patient records from the National Pediatric Trauma registry, representing all pediatric trauma patients treated at affiliated hospitals from April 1994 through December 1996. Records with incomplete information were eliminated from the study, leaving 8,081 usable patient records.
Measurements: A total of 14 variables are selected from the 81 values present in the National Pediatric Trauma Registry as independent variables for the artificial neural networks. Each neural network produces nine output values: five for categorizing the patient’s injury severity, three for the LOS in the PICU, step-down unit, and floor units, and one for the patient’s total LOS.
Results: A fuzzy ARTMAP neural network accurately categorizes 88% of mortality patients and 58.3% of critical PICU patients. A backpropagation neural network succeeded in predicting the total LOS to within 1 day for 51.4% and the ICU LOS to within 1 day for 70.4% of all evaluated patients.
Conclusion: Information available in the first 10 mins of a patient’s presentation at the emergency room can be used by an artificial neural network to predict injury severity and LOS. Artificial neural networks enable more effective resource planning and patient management.
Walczak, Steven and Scorpio, Ronald J., "Predicting Pediatric Length of Stay and Acuity of Care in the First Ten Minutes with Artificial Neural Networks" (2000). School of Information Faculty Publications. 205. | https://scholarcommons.usf.edu/si_facpub/205/ |
Indigenous African Spirit Technologies(IAST)
NOTE: **You May Join this 5-session program during Session #1 or Session #2. After Session #2, Registration is closed for this 5-session series.
Indigenous African Spirit Technologies is a 5-session IntensiveTraining that will meet 5 times for 5 days during a 1-2 year period.
We will meet 12 miles NW of Asheville, NC at
Indigenous African Spirit Technologies Session #1
June 5-9, 2019
Session #1:
Elemental Medicine
We will move into experiencing the inherant Medicine of the 5 Elements of Dagara Cosmology: Earth, Fire, Water, Nature & Mineral.
Indigenous African Spirit Technologies Session #2
October 9-13, 2019
(may be taken as 5-session course or individually)
Session #2:
Ancestralization
We will create the Ritual of Ancestralization and connect deeply with those that have gone before us.
“Dagara people’s main job is to look the dead in the face, to treat their bodies not as remains but as temples of grace and beauty continuing from this world to the other. People grieve the passing of loved ones, though in this grief they stress beauty and community and continuity. The handing over of the loved one to the realm of the ancestors is what we call ancestralization”. It allows for a sense of completion in the vast array of duties following the passing of a person. In this five-day event, we will address this issue of fulfilling our duties toward the dead in the interest of transforming restlessness into rest, discontinuity into continuity and homelessness into homecoming.” -Malidoma Patrice Some´
A Note from Malidoma:
“The time for a vigorous act of devotion to, and embracing of the wisdom of indigenous Africa has come. After centuries of silence and in hiding, the powers and wisdom of the ancestors are rising up to lead the world into the next level of consciousness and spirituality. As we know, the continent is not just the birthplace of mankind, it is also the repository of profound unseen powers and technologies on standby to contribute to a radical healing change much needed in the world today. This calls for some militant initiative on the part of those in whose heart ancient Africa speaks, to check in for this exciting and compelling journey home where they can expect to find how much of the old in them has been waiting to burst in service of the world’s need to heal and to transform. This training is offered in response to that call.
Designed for those raised in cultures with a high dose of militantism who want to serve the purpose of this new era, this multi-part program is being created to lay the groundwork, deeply and personally, for a leap into the magical and spiritual technological legacies of our ancestors.
Grounded in radical exploration of the elements of cosmology, Fire, Water, Earth, Nature, and Mineral, this program aims at enriching our working relationships with them in order to anchor ourselves more fully in this world and to be of greater service to all living beings. We will create, experience and learn to provide for others, ritual involving each element and its healing properties, thus fostering healing for ourselves, others, and our communities.
In addition, through the rituals of Ancestralizaton, we will manifest a response to our own desire for a deeper understanding of and more intimate daily interaction with the ancestors, those who have left the visible earth plane and now carry the responsibility to monitor our growth from the spirit world as we meet our duties in this world.
We will explore the art and science of Talisman making and acquire Tools of Protection and the practical applications of these ancient representations of hidden power and protection. We will learn to apply these creative skills in our work with others who seek deeper meaning in their lives.
During the final sessions we will create ritual experiences which will address the particular needs of our growing community; embracing such issues as health, abundance, grief, growth & connection with the Otherworld. We will delve into the True Nature of each individual's Purpose and Medicine.
We will meet for five days together~ two to three times, yearly, for a minimum of five sessions total.
Our gatherings will begin on Wednesday evening with supper, and conclude by noon on Sunday.
Copyright 2010 Ancestral Events. All rights reserved. | http://www.ancestralevents.com/dr_malidoma_patrice_som%C3%A9_asheville_dagara_inspired_village/indigenous_african_spirit_technologies_2016-2017__2018-2019 |
Followers of the Path of Harmony, druids use natural magic. They are primarily healers with a variety of spells they can learn to aid their realm mates. They receive basic buffs and can specialize in buffs that are unique in the realm. Druids have some offensive capabilities. Besides the ability to pick up a weapon and swing it at an enemy, they can cast poison spells to physically harm their opponent and cast root spells to freeze their opponent in place. They are also able to summon Nature's spirits as companions to travel or fight beside them. The role of a healing druid can be exacting. It takes a lot of patience, dedication and quick reflexes to keep your group healthy and performing their best. A druid can choose to spend his life alone with his spirit companion, dedicated to a group, or a little of both.
Races
Attributes
Primary: Empathy
Secondary: Constitution
Tertiary: Strength
Abilities
Armor: Cloth, Leather, Reinforced, Scale
Weaponry: Staves, Blunt, Blades
Shield: Small
Miscellaneous: Sprint
Specialization
Spells
- Regrowth
- Regrowth Specialization
- Nurture
- Nuture Specialization
- Nature Affinity
- Nature Affinity Specializaton
Autotrain
Tactics
PVE
RVR
Realm Abilities
Useful Realm Abilities
Neutral Realm Abilities
Useless Realm Abilities
Realm Rank 5 Ability:
|Name||Nature's Womb|
|Reuse||10 minutes|
|Effect||
|
An instant cast spell that silences the druid for 5 seconds and converts all damage taken for the duration into healing the druid. | https://camelotherald.fandom.com/wiki/Druid?diff=9444&oldid=9423 |
Students are empowered when they understand their own hearing loss.
Career Education
Students can plan for life after high school by developing daily living skills and gaining vocational experience.
Communication
Students who are Deaf or Hard of Hearing need a rich language base and strong communication skills to succeed socially, academically, and vocationally.
Family Education
Empowering families with information allows them to support their child and participate effectively in the educational team.
Functional Skills for Educational Success
Educational success depends on a student's ability to access, learn, and apply new information in a variety of ways.
Self-Determination and Advocacy
As they grow older, students become aware of their unique needs and learn how to ensure their needs are met.
Social-Emotional Skills
Social and emotional skills for students who are Deaf or Hard of Hearing include self-management, building support networks, practicing social interaction, and more.
Technology
Assistive technology allows students who are Deaf or Hard of Hearing to perform various tasks, access educational content, or use technology in general. | https://mdelio.org/deaf-hard-of-hearing/expanded-core-curriculum |
Demand for Codava land autonomy, tribal status, not for religious minority: CNC President
Mysuru: “The consistent stand of the Codava National Council (CNC) since the last 28 years has been the demand for ‘Codava land autonomy’ and to declare Kodava community as a tribe and accord it Tribal status. It has never been its demand for a religious Minority status,” said CNC President N.U. Nachappa.
Addressing a press conference at the Patrakarthara Bhavan here this morning, he said, however, there are forces inimical to the Kodava cause who are trying to weaken it by demanding a religious status.
“Our demand is always for the Kodavas to be given tribal status and not for a separate religion or even caste. We are firm on the decision and we will not withdraw from this demand at any cost,” he said.
A memorandum had been submitted to the Centre through Kodagu Deputy Commissioner recently in this regard. “There is a conspiracy among a few people including a few Kodavas themselves to derail this movement. The Kodavas come under the Hindus and to keep asking whether we are Hindus are not is redundant,” he said.
There is a consistent attempt in a few media circles and especially on Feb. 21 and 22 that the CNC had made a demand for separate religious status. “Especially on the International Day for Elimination of Racial Discrimination, a photograph and videograph of mine was published that after the Lingayats demand for religious minority tag, now it is the turn of Kodavas,” he said.
In spite of clarifying many times that this was not the stand of the CNC but the demand for Codava land autonomy and tribal status, efforts are on to besmirch the reputation of the CNC by such false claims, he said.
He charged that the Leftists, many betrayers among Kodavas and anti-national Maoists are responsible for such false propaganda.
The post Demand for Codava land autonomy, tribal status, not for religious minority: CNC President appeared first on Star of Mysore. | https://kannada.club/demand-for-codava-land-autonomy-tribal-status-not-for-religious-minority-cnc-president/ |
New York City, June 29, 2011—PEN American Center, the largest branch of the world’s oldest literary and human rights organization, today announced changes to its by-laws that will open the ranks of its membership. Comprised of more than 3,400 writers, translators, editors, and other literary professionals across the country, PEN is a membership organization devoted to defending free expression and advancing literature throughout the world.
Prior to a unanimous vote by PEN’s Board of Trustees on June 15, most authors were required to have published two books to join PEN. PEN’s by-laws have now been amended to allow writers to apply for membership after the publication of their first book. Playwrights and screenwriters may join after producing one work in a professional setting. Others in the literary community who have achieved recognition in the field—e.g., publishers, editors, literary agents, scouts, and publicists—may also apply to become members of PEN.
The decision to amend PEN’s membership criteria was reached after full discussion. PEN’s membership committee unanimously proposed a recommendation to its trusteeship, by-laws, and executive committees, all of which contributed edits and approved the final proposal brought before and ratified by PEN’s board.
Anyone wishing to apply to PEN may download an application at www.pen.org/join. Completed applications should be sent to [email protected]. Annual membership dues are $100. PEN also welcomes associate members, a tier of membership open to all those who support PEN’s mission regardless of professional affiliation. Associate membership remains unchanged in all ways. Annual associate membership dues are $40, or $20 for students. Inquiries about PEN membership or associate membership may be directed to Alena Graedon, Manager of Membership and Literary Awards. | https://pen.org/press-release/pen-american-center-announces-new-membership-criteria/ |
Building information modeling (BIM) is a building design and documentation methodology based on coordinated, reliable high quality information. It enables design and construction teams to create and manage information about a building project consistently and reliably across the scope of the project.
The information is stored in a single building model. This ensures that the information is coordinated, consistent, and complete.
· BIM is a process which goes far beyond switching to a new software.
information gets the power of BIM.
· Improved productivity due to easy retrieval of information.
· Increased coordination of construction documents.
· Increased speed of delivery.
· Reduced costs, minimize waste on-site. | http://eng-haitham.weebly.com/bim.html |
Introduction {#s1}
============
The ability to anticipate impending environmental change(s) and mount a preparative response is crucial to the fitness of all organisms [@pone.0005485-Johnson1], [@pone.0005485-Dodd1]. Such preparatory behavior has been observed over a wide range of time scales (e.g. daily or seasonal variations) and is mediated via sensing, internalizing and subsequently recalling fluctuation patterns in the specific environmental factor(s) (EFs). Interestingly, such behavior can also result from the ability of biological systems (even microorganisms) to internalize and use reproducible interrelationships among EFs such that by sensing a change in one or few EFs (i.e. proxy variables) they are informed of impending changes in other EFs [@pone.0005485-Tagkopoulos1]. In other words, anticipatory or preparative behavior is a manifestation of gene regulatory networks that are appropriately structured to reproduce the cyclic nature and interrelatedness of EFs that have constrained their evolution [@pone.0005485-Baliga1].
In context of the diurnal cycle, anticipatory behavior appears widely throughout the eukaryotes and has been observed in some bacteria and is typical of organisms possessing circadian clocks [@pone.0005485-BellPedersen1]. However, photoresponsive anticipatory behavior is yet to be observed in archaea. The halophilic archaeaon *Halobacterium salinarum* was considered a prime candidate for LD entrainment of transcription owing to the presence in its genome of genes for four opsins, one putative cryptochrome and an ortholog of the bacterial clock component KaiC [@pone.0005485-DasSarma1]. *H. salinarum NRC-1* uses light as a source of information for physical relocation towards favorable wavelengths of light or away from damaging radiation [@pone.0005485-Hoff1], [@pone.0005485-Spudich1], [@pone.0005485-Spudich2], [@pone.0005485-Spudich3], [@pone.0005485-Spudich4]. Under anoxic conditions it can use light-driven ion pumping by bacteriorhodopsin (bR) as means for producing ATP phototrophically [@pone.0005485-Krebs1], [@pone.0005485-Sumper1], [@pone.0005485-Hartmann1]. Taken together with substantial evidence for light-mediated global gene regulation in this organism [@pone.0005485-Baliga2], [@pone.0005485-Baliga3], [@pone.0005485-Twellmeyer1], these observations make a compelling case for investigating the feasibility of entraining global expression changes in *Halobacterium salinarum NRC-1* by prolonged culturing under diurnal 12h∶12h light∶dark (LD) cycles.
Here we present results of these experiments in which we detected free-running rhythms for at least 72 hours in up to 12% of all genes in *H. salinarum NRC-1* under constant darkness post-entrainment with 3 days of LD cycles. Remarkably, we observe that despite maintaining constant O~2~ during this experiment, a significant fraction of cycling genes are those that are also independently regulated by changes in O~2~ concentration [@pone.0005485-Schmid1]. This is interesting because O~2~ is another EF that has dominant influence on haloarchaeal physiology as a result of poor gas solubility in hypersaline environments. As such, we have previously demonstrated that a significant number of genes (at least 10%) in *H. salinarum NRC-1* are differentially regulated as a direct consequence of changes in O~2~ availability [@pone.0005485-Schmid1]. We conclude that *H. salinarum* can take advantage of coupled changes in sunlight and O~2~ such that it can use the L∶D cycle to anticipate higher levels of O~2~ during nighttime and lower levels during daytime. Given that entrainment of halobacterial physiology was best accomplished under nutrient limited condition we discuss this finding as a possible mechanism for maximizing resource utilization.
Results and Discussion {#s2}
======================
We investigated possible diurnal entrainment of gene expression in *H. salinarum NRC-1* by subjecting cultures at various cell densities (Supplementary [Table S1](#pone.0005485.s002){ref-type="supplementary-material"}) to 72 hours of light∶dark (L∶D) changes on a 12∶12 hour cyclic schedule. Cells were harvested over 3 or 4 hour intervals for up to 75 hours in continuous darkness post-entrainment ([Fig 1a](#pone-0005485-g001){ref-type="fig"} and Supplementary [Table S1](#pone.0005485.s002){ref-type="supplementary-material"}). The cell pellets were flash frozen and subsequently processed for transcriptome analysis using whole genome microarray hybridization [@pone.0005485-Baliga3], [@pone.0005485-Ideker1]. The duration of each experiment, sampling frequency and cell densities over which the experiments were conducted (as estimated by optical density (OD) at 600 nm) are reported in Supplementary [Table S1](#pone.0005485.s002){ref-type="supplementary-material"}.
{ref-type="supplementary-material"}). b, Frequency histogram of genes detected with periodic transcriptional changes (binned at intervals of 0.001 hr^−1^, p\<0.2) using Lomb-Scargle analysis. c, Spectral density (black line) of the histogram in (a) shows two dominant frequencies of ∼12.5 and ∼21 hours; the blue swath shows data distribution of normally distributed gene expression changes. d, Five k-means clusters of periodic transcriptional changes of the 290 genes (from Experiment A) in (a, b) are visualized as a heatmap \[average period is shown in parentheses and overrepresented GO or KEGG physiological functions (p\<0.01) are also indicated\]. The phasing of the diurnal L∶D cycle is indicated at the top of the heatmap with alternating white and shaded rectangles, respectively. e, Phase alignment of periodic gene expression changes shows co-induction of related cellular functions according to the diurnal cycle. DNA replication, tyrosine metabolism and ion-coupled transporters were upregulated during the middle of the light and dark phase with a period of 13.6 hours. Transcription of genes encoding components of NADH dehydrogenase (*ndhG3* and *ndhG4*), cytochrome oxidase (*coxB*), the urea cycle and glutamine-glutamate metabolism peaked at the transitions from one phase to the next. Finally, nucleotide sugar metabolism, general sugar metabolism, and DNA integration were maximally induced during the latter half of the dark phase.](pone.0005485.g001){#pone-0005485-g001}
The resulting microarray data (Geo accession number: GSE15282) were analyzed for periodic expression patterns using the Lomb-Scargle (LS) method [@pone.0005485-Glynn1] (see [methods](#s3){ref-type="sec"} for details). The LS analysis makes use of a least squares fit of sinusoidal curves to a given time series, and thus does not require evenly spaced data and is tolerant to missing data points [@pone.0005485-Lomb1]. The null distribution for the periodogram was also derived to determine statistical significance (p-value) of detecting oscillatory gene expression patterns [@pone.0005485-Scargle1]. The application of this analysis to 5 extended time courses (3 experimental and 2 controls with durations up to 75 hours with a 3--4 hour sampling frequency) allowed us to investigate oscillatory expression patterns with periods ranging from 6 hrs to \>30 hrs. A gene was considered to have oscillatory behavior if a periodic pattern was detected in its expression with a p-value\<0.2 in its respective LS periodogram ([Figure 1b](#pone-0005485-g001){ref-type="fig"} and Supplemental [Figure S1](#pone.0005485.s001){ref-type="supplementary-material"}). Consistent with the 3-day 12∶12 L∶D entrainment regimen, statistically significant periodic expression patterns with dominant periods of ∼13.0 hrs or ∼21 hrs were detected in a total of 290 genes (∼12.1% of the genome) in Experiment A and 230 genes (9.6% of the genome) in Experiment B ([Fig 1c](#pone-0005485-g001){ref-type="fig"}, Supplementary [Figure S1](#pone.0005485.s001){ref-type="supplementary-material"}). When expanded to include transcriptionally-linked genes within operons [@pone.0005485-MorenoHagelsieb1] (Koide et al., submitted to *Mol Sys Bio*) this represents potential periodic transcription of up to 636 genes in Expt A (27%) and 460 genes in Expt B (19%). An overlap of 167 genes between these gene-sets demonstrated significant reproducibility across the two experiments (p\<10^−8^). Significantly, periodic gene expression with either of the two dominant frequencies was not observed at a lower cell density (OD~600~\<0.4) (this is discussed further below), in control cultures that received no entrainment but were otherwise processed identically; or after shuffling/randomization of the expression-matrices (Supplementary [Figure S1](#pone.0005485.s001){ref-type="supplementary-material"}).
Genes with significant periodic expression patterns were further investigated in context of cellular physiology. This identified several classes of expression profiles, each with a distinct period and phasing and several with significant over-representation of diverse function categories ([Fig 1d--e](#pone-0005485-g001){ref-type="fig"}). This preliminary integrated analysis demonstrated the diurnal synchronization of a large number of linked enzymatic steps including key steps in the synthesis of nucleotides ([Figure 2](#pone-0005485-g002){ref-type="fig"}, Supplementary [Figure S1B](#pone.0005485.s001){ref-type="supplementary-material"} and Supplementary [Table S2](#pone.0005485.s003){ref-type="supplementary-material"}). Moreover, it was possible to phase-align several classes of oscillatory gene expression changes with the L∶D cycle ([Fig 1e](#pone-0005485-g001){ref-type="fig"}). This revealed that related cellular processes align well with respect to patterns of co-induction within the entrained transcriptional program.
{#pone-0005485-g002}
Interestingly, diurnal entrainment of gene expression was maximally observed above a cell density (OD~600~\>0.4) (Supplementary [Figure S1](#pone.0005485.s001){ref-type="supplementary-material"}) at which *H. salinarum NRC-1* is known to undergo a large physiological transition that involves the differential regulation of over 63% of all genes (Facciotti et al., submitted to *J. Bact*) through diverse mechanisms including activation of a large number of alternate promoters, terminators and putative ncRNAs (Koide et al., submitted). Not surprisingly, transcription of a significant fraction of cycling genes is also independently induced at this growth phase (Experiment A: p = 7×10^−5^; Experiment B: p = 3.7×10^−7^). This growth-phase dependent phenomenon results from exhausted nutritional resources including decreased oxygen carrying capacity in the medium - conditions akin to those in the natural environment of *H. salinarum NRC-1* [@pone.0005485-Oren1] (Facciotti et al., submitted). Consistent with this observation, the 135 transcripts that are both periodically induced upon diurnal entrainment (including 70 genes with peak expression during daytime) and also independently upregulated at high cell density are significantly enriched for anoxic functions [@pone.0005485-Schmid1] ([Figure 3](#pone-0005485-g003){ref-type="fig"}, Supplementary [Table S3](#pone.0005485.s004){ref-type="supplementary-material"}) [@pone.0005485-Schmid1]. Surprisingly, the converse was also true - 45 transcripts that are typically downregulated at this growth phase and also independently repressed by a decrease in oxygen availability were also diurnally entrained with maximal expression during nighttime [@pone.0005485-Schmid1] ([Fig 3](#pone-0005485-g003){ref-type="fig"}; Supplementary [Table S3](#pone.0005485.s004){ref-type="supplementary-material"}). Remarkably, the distinct partitioning of periodic transcriptional changes in oxic and anoxic genes continues for at least 72 hours post-entrainment ([Fig 3A](#pone-0005485-g003){ref-type="fig"}). This clear split in oscillatory behavior of genes associated with oxic and anoxic functions strongly suggests synchronization and entrainment of oxygen-responsive physiologies according to the L∶D phase. Taken together these results demonstrate that nutrient and oxygen-limited conditions are the most conducive to entrainment with L∶D cycles -- indicating perhaps the importance of synchronizing gene expression for efficient resource utilization under such conditions. Again, this periodic switching between oxic and anoxic physiologies was observed post-entrainment with the L∶D cycle, in constant darkness, and in culture conditions that were controlled to maintain constant dissolved oxygen (Supplementary [Table S1](#pone.0005485.s002){ref-type="supplementary-material"}). However, one could argue that natural oxygen consumption during aerobic growth and the subsequent adaptive shift to anaerobic physiology might have induced spontaneous cycling of oxic and anoxic gene expression similar to a phenomenon observed during continuous culturing of yeast [@pone.0005485-Tu1]. We can rule out such a phenomenon because control experiments that were conducted simultaneously and at the same cell density did not result in oscillatory expression of oxic and anoxic physiology genes. Thus, we conclude that the 12∶12 L∶D entrainment indirectly induced cycling of oxygen-related physiologies and speculate that this might be an outcome of a natural relationship between changes in light and oxygen that has been internalized by *H. salinarum NRC-1*. This was initially intriguing because in most aquatic environments the direct physical coupling between light and oxygen via temperature is often confounded by diverse hydrological (river inflow, tides, rainfall, etc.) and biological (e.g. the balance between photosynthesis and respiration) phenomena [@pone.0005485-Saenger1], [@pone.0005485-ValdezHolguin1]. Further investigation into the physical characteristics of the natural hypersaline environment of halophilic archaea provided clues into the potential implication of light-mediated entrainment of oxygen-associated physiologies.
![Entrained genes are directly linked to the oxygen and growth response in *H. salinarum NRC-1*.\
Three classes of average mRNA profiles for 180 of the 290 genes detected as cyclers in Experiment A. Expression profiles in all three panels are color-matched to indicate transcript profiles for the same three sets of genes over the LD cycle (A), in response to oxygen (B) and during growth in a batch culture (C). In panel A The period of oscillations in transcription upon entrainments is indicated as is the L∶D cycle (open∶grey boxes). Average transcript level changes in the same three groups of genes are plotted over the course of the growth curve for *H. salinarum NRC-1* (data from Facciotii et al. submitted). (C) The transcriptional response of these genes to sudden inflow of O~2~ after \>6 hrs of anoxia \[O2 levels are shown as a magenta dotted line (see secondary y-axis)\] (Schmid et al. 2007).](pone.0005485.g003){#pone-0005485-g003}
Extreme haloarchaea such as *H. salinarum NRC-1* thrive in closed ponds or terminal lake systems (such as the Great Salt Lake or the Dead Sea) with salinities in excess of 100--150 g salt L^−1^ [@pone.0005485-Oren2]. Oxygen solubility is extremely poor at such high salinities and, not surprisingly, in addition to aerobic respiration most halophilic organisms also require alternate means of energy production such as phototrophy, denitrification and other dissimilatory processes [@pone.0005485-Baliga4], [@pone.0005485-Bolhuis1], [@pone.0005485-Falb1], [@pone.0005485-Ng1]. Adaptive responses that enable efficient conditional switching between these varied modes of energy production are critical for the energetically expensive lifestyle of halophilic organisms [@pone.0005485-Baliga3], [@pone.0005485-Oren1], [@pone.0005485-Betlach1], [@pone.0005485-Muller1], [@pone.0005485-Ruepp1], [@pone.0005485-Shand1]. For instance, in these environments, temperature and salinity are generally considered to be the dominant parameters influencing dissolved oxygen content [@pone.0005485-Ashton1] as biological primary production (photosynthesis) is greatly reduced [@pone.0005485-Pinckney1], [@pone.0005485-Wieland1]. The physicochemical dependence of O~2~ concentration on temperature and salinity is well known [@pone.0005485-Stumm1], [@pone.0005485-Han1]. Notably, concentration of dissolved O~2~ in water drops as its temperature goes up; the solubility of O~2~ at 0°C is about twice its solubility at 30°C. Furthermore, there is evidence for an average diurnal cycle of 1--2°C in surface temperature of Great Salt Lake, a prototypically closed hypersaline ecosystem, with lower temperatures at nighttime [@pone.0005485-Department1]. Hence, higher oxygen levels are generally expected at nighttime relative to the warmer daytime period. Our data suggests that this physicochemical relationship between light and oxygen in the natural closed hypersaline environment has been imprinted onto the regulatory architecture of indigenous organisms such as *H. salinarum NRC-1*. In other words, under nutrient limited conditions halophilic archaea take advantage of this relationship to streamline their physiology by anticipating present and future linked changes in oxygen availability and operate oxically during nighttime and anoxically during daytime.
While such anticipatory behavior has been observed over shorter time scales [@pone.0005485-Tagkopoulos1], this study shows sustained oscillations in oxic/anoxic transitions over longer time scales through several cell divisions even after the L∶D stimulus is removed and the cells are maintained under constant conditions. Large families of haloarchaeal regulatory proteins (signal transducers and TFs) with physically linked domains for sensing light and oxygen are further evidence of tight coupling between these environmental factors and the biological architecture of the gene regulatory networks [@pone.0005485-DasSarma1], [@pone.0005485-Baliga4], [@pone.0005485-Mascher1]. Finally, the discovery of diurnal entrainment of gene expression in an archaeon also raises important questions regarding the origin of light-responsive clock mechanisms. This is because archaeal information processing machinery is assembled from components that share ancestry with eukaryotic (general transcription factors and RNA polymerase) and bacterial (sequence-specific transcription regulators) counterparts [@pone.0005485-Geiduschek1]. Furthermore, components of both bacterial [@pone.0005485-Dvornyk1], [@pone.0005485-Taniguchi1] and eukaryotic [@pone.0005485-Lin1] clocks are encoded in its genome [@pone.0005485-DasSarma1], [@pone.0005485-Ng1]. Indeed, further detailed experimentation is necessary to ascertain precise phasing, temperature compensation, adaptability to different periods of entrainment etc. to ascertain the mechanistic underpinnings of this diurnal entrainment and its physiological implications. Nonetheless, our results demonstrate that even extremophilic archaea can use the diurnal day/night cycle to their advantage by anticipating future physicochemically linked changes in other EFs.
Materials and Methods {#s3}
=====================
Culturing, sampling and RNA extraction {#s3a}
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Wild type *Halobacterium salinarium NRC-1* was cultured from a single colony in Complete Medium (CM) [@pone.0005485-DasSarma2]; at 37°C with shaking at 125 rpm (Innova Waterbath, NewBrunswick Scientific, Edison, NJ). Cells were incubated under entrainment conditions (12∶12 L∶D cycle; daylight was simulated with full spectrum light at 150 µE/m^2^/s) or in continuous darkness (control) for three to four days prior to sampling. Post-entrainment Samples (2 ml) were collected periodically (every 3--4 hours) for up to 72 hours in continuous darkness, under constant cell density. The cell density was maintained by replacing a fixed volume in the culture (typically 30 mls) with equivalent of fresh CM every 3--4 hours [@pone.0005485-Mori1]. Comparative analysis with a similarly processed control culture discounted any unaccounted perturbations that were introduced by this periodic dilution. Cell pellets were harvested by centrifugation at 1600 rcf for 2 min, decanted, flash-frozen in liquid N~2~ and stored at −80° until RNA extraction. Total RNA was prepared using the Absolutely RNA kit (Qiagen, Foster City, CA, USA). RNA quality was examined by spectrophotometry and BioAnalyzer (Agilent, Santa Clara, CA, USA) analyses and DNA contamination was ruled out by PCR with 16S rDNA primers.
Microarray Analysis {#s3b}
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*H. salinarum NRC-1* microarrays were fabricated at the Institute for Systems Biology Microarray Facility. Each microarray slide contains a unique 70mer oligonucleotide for each of the 2400 genes spotted in quadruplicate at two spatially distinct locations. Labeling, hybridization and washing have been previously described [@pone.0005485-Baliga3]. Statistical significance of differential gene expression was determined using the maximum likelihood method [@pone.0005485-Ideker1]. [All microarray data reported in the manuscript is described in accordance with MIAME guidelines.]{.ul}
Frequency Analysis {#s3c}
------------------
To examine the relative periodicity of genes in the constant light and constant dark experiments we used the Lomb normalized periodogram to estimate the spectral power as a function of angular frequency [@pone.0005485-Glynn1], [@pone.0005485-Press1], [@pone.0005485-Vityazev1], [@pone.0005485-Lomb2]. This method can be used to evaluate whether a given gene is periodic or is the result of noise or some other non-periodic process (a p-value associated with the significance of the each peak in the periodogram can be easily calculated). There are other methods that would allow us to calculate periodograms and statistically evaluate whether a signal was truly periodic [@pone.0005485-Scargle1], [@pone.0005485-Press1], [@pone.0005485-Wichert1]; we chose the Lomb periodogram in part because it does not require evenly sampled data. Further, obeying the Nyquist limit, the highest frequency allowed was 0.167 hr^−1^ (period = 6 hrs). For our analysis the lowest frequency detected was 0.033 hr^−1^ (period = 30 hrs). This allowed for detection of a 24 hour signal and also for the experiment duration to contain two full periods over which to detect.
The Lomb periodogram, P~N~(ω), is calculated as follows:where mean and variance are calculated as per usual:Tau is an offset that makes P~N~(ω) invariant to shifts in all time-points by a constant; tau is defined by the relation:This offset removes phase from the calculation. The Lomb periodogram is analogous to least squares fitting of sins and cosines to our signal in the time domain.
The significance of periodicity of expression changes for each gene is then calculated as the probability that a peak in the periodogram with intensity greater than z is due to a random or non-periodic process [@pone.0005485-Scargle2]:Where M is the effective number of independent frequencies sampled, which in our case is well approximated by N, the number of samples [@pone.0005485-Horne1]. Thus, for each of the 2400 unique genes the analysis of a single time series resulted in a spectrogram and the significance of the maximum peak in that spectrogram.
Data Integration and Visualization {#s3d}
----------------------------------
Data were explored using the Gaggle and Firegoose framework for integrating diverse software tools and algorithms including Cytoscape, Data Matrix Viewer (DMV), KEGG, STRING, the R statistical package and MeV [@pone.0005485-Bare1], [@pone.0005485-Shannon1].
Supporting Information {#s4}
======================
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A. Results from Lomb-Scargle analysis are presented as periodograms for each experiment described in [Supplementary Table 1](#pone.0005485.s002){ref-type="supplementary-material"}. Only genes with p\<0.2 were considered to be cyclic in their expression pattern. Note that a strong banding pattern with p\<0.2 is only observed in experiments A and B. B. Reproducibility of periodic transcriptional changes in 12 genes of diverse functions post-entrainment with three days of 12∶12 LD. Transcriptional changes over 48 hours of "memory" phase are shown along with putative functions.
(0.94 MB PDF)
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Click here for additional data file.
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Experiment design, culturing parameters and sampling schedule.
(0.18 MB PDF)
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Click here for additional data file.
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Genes with oscillatory gene expression profiles in Experiments A and B, period of oscilattion and significance.
(0.38 MB PDF)
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Click here for additional data file.
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The number of genes and average period in each of the clusters presented in [Figure 3](#pone-0005485-g003){ref-type="fig"} of the Experiment A.main text. The number of genes correlated to high or low oxygen (taken from Schmid et al. 2007) are also given.
(0.13 MB PDF)
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Click here for additional data file.
We thank Monica Orellana for insightful comments and her expert advice on O~2~ solubility in marine and hypersaline waters. We also thank Carl Johnson for guidance in setting up the diurnal entrainment experiments and analyzing data.
**Competing Interests:**The authors have declared that no competing interests exist.
**Funding:**This work was supported by grants from NIH (P50GM076547 and 1R01GM077398-01A2), DoE (MAGGIE: DE-FG02-07ER64327 and DE-FG02-07ER64327), NSF (EF-0313754, EIA-0220153, MCB-0425825, DBI-0640950) and NASA (NNG05GN58G) to NSB and an NSF OPP Postdoctoral Fellowship to KW. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
[^1]: Conceived and designed the experiments: KW KiM RB NSB. Performed the experiments: KW KiM MP NSB. Analyzed the data: KW KiM RB NSB. Contributed reagents/materials/analysis tools: KW RB NSB. Wrote the paper: KW RB NSB.
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Deteccion de mutaciones en el gen F8 en mujeres portadoras y en pacientes con hemofilia A. Identificacion de una mutacion nueva.
INTRODUCTION
Hemophilia A (HA) is an X-linked recessive bleeding disorder caused by the total or partial absence or dysfunction of blood coagulation factor VIII (FVIII) (1). Severe HA (sHA) is characterized by plasma levels of FVIII < 0.01 IU mL-1 (< 1% of normal levels) (2) and is commonly caused by the intron 22 inversion (frequency of approximately 45%) (3) or the intron 1 inversion (frequency of approximately 2%) (4) in the F8 gene; the rest of the causative mutations is greatly diverse. In the Factor VIII Variant Database, 2,015 unique mutations have been reported to date (5).
Because of the X-linked inheritance pattern of HA, mostly men are affected, while their female relatives may be heterozygous for the mutation, also referred to as carriers. HA carriers are expected to have FVIII plasma concentrations of nearly half of that of healthy individuals, which is generally sufficient for normal hemostasis. However, a wide range of FVIII levels has been reported in carriers: from very low, resembling male patients, to normal (6). For this reason, molecular diagnosis is the method that offers the most certainty about the carrier status of HA (7).
Similarly to male HA patients, the severity of the bleeding tendency of carriers is correlated to the type of mutation in the F8 gene (8). It is important to assess the bleeding risk in HA carriers to improve their care, an aspect often not recognized by physicians and health care professionals. Prophylactic factor substitution or alternative treatments may prevent abnormal bleeding such as menorrhagia, in surgical and dental procedures, childbirth, or the treatment of injuries. Also, the molecular diagnosis of HA carriers allows for genetic counseling and prenatal diagnosis of the disease, which have become part of the comprehensive care for HA in many countries (9). On the contrary, this is not an established practice in the Venezuelan healthcare system. The only other study reported was the indirect diagnosis of carriers realized by the analysis of intragenic polymorphisms in the F8 gene (10).
In this study, we report the results of the first direct molecular diagnosis of HA carriers in Venezuela. In addition, we report the causative mutations in the F8 gene of 6 Venezuelan sHA non-related male patients, including a mutation that has not been previously reported.
PATIENTS AND METHODS
Patients and potential carriers
Twelve non-related male sHA patients, diagnosed biochemically at the National Hemophilia Center located at the Banco Metropolitano de Sangre (Caracas, Venezuela), were studied. The mothers of sHA patients with identified causative mutations [both from the present study and from a previous work (11)] were investigated for the presence of the genetic alterations found in their sons. Informed consent was obtained from all participants.
Detection of F8 mutations
Genomic DNA extraction was performed from peripheral blood samples by standard protocols using chloroform purification and ethanol precipitation (12). Detection of F8 mutations was initially performed in all sHA patient samples, and once a mutation was identified, it was investigated in their mothers by the same method. The presence of the intron 22 inversion was investigated using a touchdown inverse PCR method, as previously described (11). Patients negative for the intron 22 inversion were then analyzed for the presence of the intron 1 inversion, as previously reported (4). Finally, the F8 was screened in all patients negative for both inversions. The entire coding region, including the flanking splice sites, the 5'- and 3'-UTR, was amplified through multiplex PCR (M-PCR), as previously described (11). The M-PCR products were screened for mutations through a mildly denaturing conformation-sensitive gel electrophoresis (CSGE) (12.5% polyacrylamide) (13). Samples displaying abnormal CSGE patterns were sequenced in the forward and reverse directions using an automated ABI 377 genetic analyzer (Applied Biosystems) at the UEGF-IVIC (Caracas, Venezuela). Mothers of patients with point mutations were analyzed by sequencing the potentially affected region of F8. Mutation nomenclature was according to the Human Genome Variation Society (HGVS) (14).
In silico analysis of missense mutations
The pathological authenticity of novel (not previously reported in the Factor VIII Variant Database) or not previously analyzed F8 gene mutations was determined through the following steps: 1) In UniProtKB (15), the domain and chain location of the mutation was determined. Information was obtained on whether the mutation occurred at an amino acid involved in cleavage, post-translational modification or disulfide bond. 2) The potential effect of amino acid substitutions was analyzed with the software UCSF Chimera, version 1.7 (16), using the tridimensional model of the crystal structure of FVIII available at the Protein Data Bank (17, 18) (PDB ID: 2R7E). 3) MutPred (19) and PolyPhen-2 (20) (version 2.2.2) were used to corroborate the probability of an amino acid substitution being deleterious. 4) Evolutionary sequence conservation of the substituted amino acids was evaluated through sequence alignment of F8 orthologues from eight vertebrate species: Homo sapiens (NP_000123), Bostaurns (NP_001138980), Canis lupus familiaris (AAB87412), Mus musculus (NP_032003), Oryctolaguscuniculus (ACA42556), Rattus norvegicus (NP_899160), Susscrofa (NP_999332), and Takifugu rubripes (NP_001027922). Sequence alignment was performed with the DnAMAN(r) software (21) and the sequences were obtained from Gene Bank.
RESULTS
Molecular diagnosis of sHA patients
F8 variants were identified in eight out of 12 non-related male sHA patients (Table I). No mutations were identified in 33.33% of the patients studied. The intron 22 inversion was detected in three patients, while point mutations were identified in five patients: two nonsense (p.S872* and p.R1985*) and three missense (p.G190C, p.D1260E and p.M2257V). The mutation p.D1260E was detected in two unrelated patients, while p.G190C has not been previously described and therefore we report it as a novel mutation for sHA. In silico analysis suggests a possible pathogenic effect of this mutation, as discussed later. Only the intron 22 inversion, p.S872* and p.R1985* mutations have been previously associated with a pathogenic effect. Altogether, were detected 6 distinct sHA causative mutations, as also discussed later. The intron 1 inversion was not found in the patients analyzed.
Molecular diagnosis of mothers of sHA patients
The six distinct causative mutations detected in this study and those found in seven patients from a previous work (11) [3 intron 22 inversions, 2 missense (p.R1966* and p.S524*), one splicing (c.6654-1G>A) and one small deletion/insertion (del_TTGT209-212) mutations] were used to identify the carrier status among the mothers of these patients. All 13 possible carriers were found to have the mutation, for a carriership frequency of 100%.
DISCUSSION
Intron 22 and intron 1 inversions
The intron 22 inversion was the most common mutation found in this study, with an incidence of 25%. In a previous study (11) we found a 41% frequency for this mutation, which is consistent with the 45% reported in other studies (3, 4). Additionally, no intron 1 inversions were found, while it is reported to cause approximately 2% of HA cases (4). We assume that the lower than expected frequencies are most likely due to the small number of patients studied. However, it should be noted that the intron 1 inversion, the second most common causative mutation of sHA, is yet to be found in Venezuelan patients, as it was not detected in this study and neither in the 54 sHA patients studied in the first and only other work of this kind in Venezuela (11).
Nonsense and missense mutations
We found two nonsense mutations that have been previously reported as sHA causative mutations: p.S872* and p.R1985* (22, 23). In addition, we detected two missense mutations that have been previously reported: p.D1260E and p.M2257V. However, the effects of these amino acid changes on the function of FVIII have not been analyzed in earlier publications.
Mutation p.D1260E was found in two unrelated patients in this study: H158 and H162 (Table I). It has been previously reported as a polymorphism (rs1800291) and the mutant allele has been associated with reduced FVIII:C levels (24, 25). However, no other missense mutation in the Asp1260 residue has been reported, it is not conserved, and PolyPhen and MutPred analysis both suggest it has no deleterious effect on the FVIII protein (Table II).
Mutation p.M2257V, also reported as a polymorphism (rs1800297), was first detected in 4/42 non-related Brazilian patients with moderate HA in whom no other mutation was found (26). The researchers considered the possibility that this relatively common alteration was polymorphic and thus analyzed 100 Dutch and 63 Brazilian unaffected individuals, none of which had the mutation. It was found in a later study in 1/7 Jamaican sHA patients (27). This patient, however, had another mutation in the F8 gene (intron 5 671-2A>G), to which the authors attribute the cause of the disease. Furthermore, the p.M2257V mutation was present in healthy family members of this patient, and the authors found a 42% heterozygosity rate of the mutation in 31 unrelated Jamaican individuals. No other missense mutations have been reported in the Met2257 residue and it is conserved in 5/8 of the species analyzed (Table II). While Met2257 generates one clash with Cys2345 (Fig. 1a), Val2257 is predicted to generate two clashes of higher overlap values with Phe2253 (Fig. 1b, orange lines). Since both valine and phenylalanine are hydrophobic amino acids, these unfavorable interactions may cause a steric hindrance effect in the C2 domain, which may affect its stability or conformation and potentially its interaction with von Willebrand Factor (VWF) and/or phospholipids. PolyPhen predicts the amino acid substitution to be benign (0.15); however MutPred calculates the probability of it being a deleterious mutation at 0.60. Even though the previous evidence is not conclusive, it would seem that this mutation is not causative of sHA because it has been found in healthy male subjects (27).To date we have not found reports of patients or healthy individuals carrying both polymorphisms (p.D1260E and p.M2257V). The allelic frequencies
reported in world population are 0.19 and 0.03 for p. D1260E and p.M2257V, respectively (28). The low frequency of allele Val2257, could explain the absence of individuals with both mutations. Even though patient H158 has two apparently innocuous mutations in F8 (p.D1260E and p.M2257V) and another pathogenic mutation was not found, an additive effect of both alterations in FVIII could not be discarded. However, this could not be further explored in the crystal structure of FVIII because it does not contain the B domain, which includes amino acid D1260.
We also detected the novel mutation p. G190C. A missense mutation in the same amino acid position, p.G190D, has been previously reported as a sHA causative mutation, but no mechanism was proposed (29). Gly190 is a highly conserved residue (Table II) located in the A1 domain, specifically in the plastocyanin-like 1 domain (18). As shown in the tridimensional structural model of FVIII, the cysteine residue may cause a steric hindrance effect (Fig. 1d); in fact, five clashes are generated in the mutant protein, four of them with carbon atoms of residue Leu69. These unfavorable interactions may affect the stability or conformation of this domain, which could affect its copper-binding property. PolyPhen predicts the amino acid substitution to be probably damaging (1.00) and MutPred calculates that the probability of it being a deleterious mutation to be 0.85 (Table II).
No mutations were identified in 33.33% of the patients studied. It is possible that the M-PCR-CSGE approach may have missed some mutations or that the mutation is outside of the region analyzed, like intronic sequence changes that might affect transcription or translation. In addition, the size of the fragment is important for the CSGE sensitivity (30) and some of the fragments analyzed in this study exceeded the recommended size (200- 450 bp) because of the adoption of previously described primers. However, this technique showed a 91% of sensibility in our previous study (11).
Carriership of severe hemophilia A
We found that all mothers of patients with sHA were carriers. In spite of the small number of mothers studied, this frequency is within the expected range. It has been calculated that the mother of a patient with sporadic HA has a probability of 0.85 of being a carrier, while in the case of familiar HA, the probability is 1.00 (31). Since we had no information about the occurrence of the disease in the families analyzed in this study, we expected a carrier state frequency between 85 and 100%.
All six mothers of patients with the intron 22 inversion were carriers of the mutation. This is consistent with other studies in which 20/20, 43/43 and 49/50 mothers were carriers of the inversion (32-34). This high probability of intron 22 inversion carriership is due to the fact that the recombination that produces the inversion is more probable during male meiosis because the homologous pairing of X chromosomes that occurs during female meiosis inhibits the bending of the tip of X chromosomes (35). In fact, it has been reported that the sex ratio frequency of this mutation is >10-fold-higher in male germ cells (22). Therefore, intron 22 inversion has a higher probability of originating in the male germ cells of the maternal grandfather than in the female germ cells of the mother.
The point mutation carriership frequency found in this study was of 100% (7/7). This result matches another study that found that point mutations have a sex ratio frequency 5 to 10-fold higher in male germ cells (22). It has been suggested that this tendency is due in part to the fact that methylation at CpG sites in the female germ line is considerably reduced (36). Since methylated cytosine is prone to deamination and further mutation to thymidine, transitions C to T and G to A occur more frequently in male germ lines. This mechanism is particularly relevant in HA because 40% of causative point mutations occur in one of 70 CpG sites of the F8 gene, even though these regions represent only 2% of the coding region of the gene (37).
The results obtained in this study highlight the importance of implementing the molecular diagnosis of HA carriers in Venezuela, given the high probability for a patient's mother to be a carrier. This information is useful for family members of yet unknown HA status who could benefit from genetic counseling for future pregnancies, which is highly relevant in third-world countries. Knowledge of the causative mutation can improve clinical care of both HA carriers and patients, as the mutation type is correlated to phenotype severity (8) and, in the case of male patients, to the risk of developing inhibitors (38).
ACKNOWLEDGMENTS
The authors gratefully acknowledge Drs. Arlette Ruiz-Saez, Apsara Boadas and Norma de Bosch for sample collection and data compilation. This work was funded by LOCTI project 4984-07. The authors stated that they had no interests which might be perceived as posing a conflict or bias.
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Lucia Lopez-Vasquez, Silvia Albanez, Carolina Pestana and Antonietta Porco.
Laboratorio de Genetica Molecular Humana B, Departamento de Biologia Celular, Division de Ciencias Biologicas, Universidad Simon Bolivar, Caracas, Venezuela.
Corresponding author: Antonietta Porco Giambra, Laboratorio de Genetica Molecular Humana B, Departamento de Biologia Celular, Division de Ciencias Biologicas, Universidad Simon Bolivar, Caracas, Venezuela. Tel./fax: +58 2129063061. Email: [email protected]
Recibido: 01-02-2016. Aceptado: 30-06-2016
Caption: Fig.1. Three dimensional representations of amino acidic residues interactions in two missense mutations: (a and b) Effect of mutation p.M2257V. (c and d) Effect of mutation p.G190C. The affected amino acids are shown in purple; the interacting amino acids are shown in cyan; clashes are represented as orange lines; sulfur atom on Cys190 is represented as a ball.
TABLE I MUTATIONS IDENTIFIED IN THE F8 GENE IN 8 OF 12 sHA MALE PATIENTS Patient Mutation* Amino acid ID change* H178 Intron 22 inversion -- H180 Intron 22 inversion -- H182 Intron 22 inversion -- H211 c.568G>T p.G190C H196 c.2615C>G p.S872X H162 c.3951C>G p.D1260E[section] H158 c.3951C>G; p.D1260E[section] c.6940A>G p.M2257V[section] H183 c.5953C>T p.R1985X Patient Type of mutation Exon/intron FVIII domain ID H178 Complex rearrangement -- -- H180 Complex rearrangement -- -- H182 Complex rearrangement -- -- H211 Missense 4 A1 H196 Nonsense 14 B H162 Missense 14 B H158 Missense 14 B Missense 25 C2 H183 Nonsense 18 A3 Patient previous ID reports ([dagger]) H178 Several H180 Several H182 Several H211 0 H196 3[double dagger] H162 2 H158 2 5 H183 30 * Mutation nomenclature was according to the Human Genome Variation Society (HGVS) (13). ([dagger]) Number of previous reports in non-related individuals according to the Factor VIII Variant Database (5). ([double dagger]) 2 reports in the Factor VIII Variant Database and 1 in a previous work in Venezuela (10). [section] Non-deleterious mutations. TABLE II INSILICO ANALYSIS OF NOVEL OR PREVIOUSLY NOT ANALYZED MISSENSE MUTATIONS Mutation* Amino acid Degree of conservation PolyPhen score change* ([dagger]) c.6940A>G p.M2257V MM/MM/M/V/V/- Benign (0.15) c.3951C>G p.D1260E D/E/E/V/T/T/G/I Benign (0.00) c.568G>T p.G190C G/G/G/G/G/G/G/G Probably damaging (1.00) Mutation* MutPred probability of deleterious mutation c.6940A>G 0.60 c.3951C>G 0.10 c.568G>T 0.85 * Mutation nomenclature was according to the Human Genome Variation Society (HGVS) (13). ([dagger]) Amino acid residue present in the Factor VIII sequence for each of the following species: Homo sapiens/Bos Taurus/ Canis lupus familiaiis/Mus musculus/ OryctoJagus cuniculus/Rattus norvegicus/ Sus scrofa/ Takifugu rubripes. | https://www.thefreelibrary.com/Deteccion+de+mutaciones+en+el+gen+F8+en+mujeres+portadoras+y+en+...-a0505302223 |
Road safety is a major issue affecting the road sector. Road accidents remain a serious impediment to sustainable human development in many of the developing member countries (DMCs) of the Asian Development Bank (ADB). Road accidents continue to be an important social and economic problem in developing countries like India. Growth in the number of motor vehicles, poor enforcement of traffic safety regulations, poor quality of roads and vehicles, and inadequate public health infrastructures are some of the road safety problems facing in India.The object of this Thesis is to present a status report on the nature of the government policy towards the Activity plans implemented till now and which has to be implemented later for the reduction of road fatalities and for the safe roads, and also giving the guidelines for financing of remedial measures, institutional framework, physical characteristics of the road, traffic control and calming measures, road safety education and enforcement issues.The aim of the Activity plans is to analyze the present situation of road safety in India and to indicate main problems in individual sector of the Activity implemented by comparing and taking the examples of some of the ASEAN Region who are successed in implementing in the individual sectors. | https://phdessay.com/road-safety-2/ |
The organic crop farming system is based on the up-to-date scientific vision of environmental problems and soil science challenges, with due regard to the crop rotation principles, thereby preserving the soil fertility alongside with weed and pest control.
The use of an organic system implies the minimized consumption of non-renewable resources. Organic crop farming contibutes to the balance-of-nature preservation, because protection of the environment and wildlife is among the priorities of such farming.
The results of a number of research studies show that the food, grown organically, contains more vitamins, nutrients and antioxidants, having an anticancer effect, than the conventional food grown in a regular manner.
Organic systems preclude any use of artificial chemicals, pesticides or fertilizers.
Certified organic products do not contain any GMOs, inasmuch as any use of GMOs is prohibited by the organic food and organic crop farming standards. | http://biofarm-organicplus.com/en/news/5-the-advantages-to-choose-certified-organic-150 |
Eucalyptus wood is a sturdy wood that is native to Australia. Eucalyptus wood has not been used as prevalently in the United States as in Australia, but it is an effective alternative to teak and other hardwoods. It is resistant to water, disease and insects, which makes it ideal for use as patio furniture. It does require some care, however, to stay in excellent condition.
Place a waterproof protective furniture cover over the eucalyptus wood furniture when not in use. Although eucalyptus is moisture-resistant, all wood eventually is ruined by moisture, so cover the furniture when it's not in use.
Mix a solution of 1 tbsp bleach, 5 tbsp dish soap and 1 gallon of bleach. Scrub the surface of the wood once or twice a year with this solution, using a soft bristle brush. Dry the wood with old towels. This removes any residue from the wood and kills any mould or mildew spores.
Spray some wood sealer protector over the wood about once per week. Rub the solution over the wood with a soft cloth to buff the wood to a shine and keep the finish in good condition. Do not use this spray if your wood is not sealed.
Paint the surface of unsealed wood with a thin coat of polyurethane sealer. Allow the sealer to dry for two hours, then apply another coat. Apply a total of three coats. This will help the wood resist water damage and protect it from scratches, stains, nicks and weathering.
Prevent further damage to the wood by keeping hot objects, such as hotplates and cooking dishes, off the surface. Wipe spills immediately with a dry towel. Do not leave the wood in a humid or extremely shady area. Cover the bottom of the furniture legs with rubber shoes to protect the bottom of the wood from rotting. | https://www.ehow.co.uk/how_6537239_care-eucalyptus-wood.html |
Аннотация: This book examines the use of football in building peace and promoting social development, focusing on case study projects in Liberia and Israel. Football has proven useful in this regard due to its popularity, uniformity and suitability in local contexts. When conflicts are resolved peacebuilding and social development serve as key challenges facing fractured communities. It examines related literature, methodological theory and context-bound reflections on the focus, rationale, challenges and possibilities associated with implementing such initiatives. Civil and transnational conflicts continue to threaten peace in contemporary society, notably in Africa and the Middle East. The book is structured as a research project, which guides readers through the process of project investigation and implementation. However, little is known about the value and implications of such projects. Some NGOs have responded to the need to stabilise social order, using a variety of mechanisms including sport. Football projects have been developed to encourage segregated groups and individuals to congregate in shared space to partake in communal sporting and social experiences.
Research on language and social interaction in scenographic settings MULTIMODALITY IN MISE-EN-SCENE COMMUNICATION.
Achievement, Cultural Identity and Community Development Adaptation of Cambodians in New Zealand.
A survey analysis in the Southern Africa Development Community INFORMATION TECHNOLOGY INFRASTRUCTURE DEVELOPMENT.
CONFLICT RESOLUTION AND PEACE BUILDING IN A COMPOSITE COMMUNITY THE IFE-MODAKEKE CONFLICT, 1800-2000. | http://www.bookin.org.ru/book/1125896 |
Globalization considerably increased probability of pandemics. Consequently, many researchers investigated what are the dynamics of rapidly spreading diseases. However, new study carried out by Swiss sociologists suggests that one important mechanism of disease dissemination was overlooked.
“Here we study the dynamics of an epidemic when the recovery of sick individuals depends on the availability of healing resources that are generated by the healthy population. We find that epidemics spiral out of control into explosive pandemics if the cost of recovery is above a critical cost,” they say.
Dangers created by global epidemics are clear. Spanish influenza killed 50 million people one century ago. And past world was less connected than the present one. Over 3 billion people travel by plane each year. Large number of interactions creates conditions for new dangerous viruses will be transmitted very rapidly. These challenges are well known and considerable efforts were invested into understanding of the diffusion of viruses.
“Important progress in understanding epidemic spreading has been made using mathematical models that capture the underlying processes and their dependence on infection and recovery rates. These studies have focused mainly on the interplay between the dynamics and the structure of interactions, on identifying the main spreaders,” the scientists note.
However, most of the contemporary mathematical models assume that disease outbreaks can be solved without treatment or that treatment capacities are unlimited. However, Lucas Böttcher and his colleagues at ETH Zürich thought that this factor can play a decisive role as well.
“A large enough healthy and productive population is crucial to enable the recovery of those that become ill: Healthy individuals are both the human resources needed to provide health services and pharmaceuticals, and contributors to the healthcare budget through taxes and insurance premiums,” the scholars explain.
Expanding epidemics reduce resources needed for its treatment and consequently reinforce itself. Computer simulations showed that situation becomes uncontrollable when recovery cost becomes critical. Moreover, this change is very fast and does not depend on social networks structuring human interaction.
“This discontinuity indicates the importance of carefully monitoring the situation in order to avoid a sudden and uncontrollable transition into the pandemic regime,” the sociologists emphasize.
Article: Böttcher, Lucas and Woolley-Meza, Olivia and Araujo, Nuno A.M. and Herrmann, Hans J. and Helbing, Dirk, Disease-Induced Resource Constraints Can Trigger Explosive Pandemics (August 6, 2014). Available at SSRN, source link. | https://www.technology.org/2014/11/14/disease-induced-resource-constraints-can-trigger-explosive-pandemics/ |
Differences and similarities in cross-cultural perceptions of boundaries: a comparison of results from two studies.
There has been substantial literature on boundary excursions in clinician-patient relationships; however, very little empirical research exists. Even less information exists on how perceptions of this issue might differ across cultures. Prior to this study, empirical data on various kinds of boundary excursions were collected in different cultural contexts. First, clinicians from the U.S. and Brazil were asked to rate 173 boundary excursions for both their perceived harmfulness and their professional unacceptability (Miller et al., 2006). In a second study, colleagues from Qatar administered a slightly modified version to mental health care professional staff of a hospital in Doha, Qatar (Ghuloum et al., 2011). In this paper, the results of these two separate studies are compared. The results showed some similarities and some differences in perceptions of the boundary behaviors. For example, both sets of cultures seem to agree that certain behaviors are seriously harmful and/or professionally unacceptable. These behaviors include some frankly sexual behavior, such as having sexual intercourse with a patient, as well as behavior related to doing business with the patient, and some disclosing behavior. There are also significant cultural differences in perceptions of how harmful some of the behaviors are. Qatari practitioners seemed to rate certain behaviors that within therapy mix disclosing or personal behavior with therapy as more harmful, but behaviors that involved interacting with patients outside of therapy as less serious. A factor analysis suggested that participants in U.S./Brazil saw a much larger number of behaviors as making up a set of Core Boundary Violations, whereas Qatari respondents separated sexual behaviors from others. Finally, a Rasch analysis showed that both cultures perceived a continuum of boundary behaviors, from those that are least harmful or unprofessional to those that are highly harmful or unprofessional. One interpretation is that cultural factors may be most influential on those kinds of behaviors that are perceived as relatively less serious. Implications for training and supervision are also discussed.
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Lucerne is a beautiful city in central Switzerland on the shore of Lake Lucerne – popular with tourists for sites like the 14th century wooden Chapel Bridge (Kapellbrücke) spanning the river Reuss. It has long been accepted that the first settlement on Lake Lucerne was the Benedictine Monastery of St. Leodegar, founded in 750 CE. That may change drastically with the recent discovery of what is being called the Atlantis of Lake Lucerne – an underwater village that dates back to 1000 BCE in the late Bronze Age. Did early tourists come there for the sites and leave with souvenir animal skin T-shirts?
Swiss archeologists and historians have long suspected that the monks weren’t the first to settle in Lucerne, but they had no proof – at least none that was readily accessible. Those who believed an early settlement might be hidden under Lake Lucerne were hampered by the lake’s thick layer of mud on its bottom. That mud came prior to the 15th century when the Krienbach river feeding it brought large amounts of rubble and debris that blocked the lake’s outflow. After that, locals built mills and dwellings and further reduced the outflow. Archeologists estimate all of this added 5 meters (16.4 feet) to the depth of Lake Lucerne.
“The construction of the lake water pipeline last year offered the first opportunity to gain an archaeological insight into the Lucerne lake bottom. On behalf of the Cantonal Archeology of Lucerne, a team from Underwater Archeology in Zurich accompanied the dredging work.”
A press release from the Cantonal Archeology of Lucerne described what was found when the lake was carefully dredged to lay a lake water pipeline for the Inseliquai lake energy center of ewl AG. Work started in December 2019 and the diving team accompanying the dredgers began finding artifacts of a lost village in March 2020. (Photos here.)
“As early as March 2020, the excavator lifted numerous wooden piles from the water in addition to alluvial sediments. The diving archeology experts quickly realized that the artificially prepared piles were prehistoric timber. Soon ceramic shards also came to light. The pipeline trench thus leads through the middle of an area with remains of pile dwellings. The dating of the timber using the C14 method and the analysis of the ceramics prove that these settlement remains were dated to the late Bronze Age, around 1000 BC.”
That means a 3,000-year-old lost village from the Bronze Age exists just four meters below the surface of Lake Lucerne. According to Ancient Origins, the timber was once piles or pylons for stilt houses with thatch roofs that allowed prehistoric humans to live near the shore safe from rising waters due to perioding flooding. That was a common building style around other Alpine lakes but this is the first evidence that there were people living at Lake Lucerne in stilt houses.
Nothing else is known about the Bronze Age Lucernians – where they came from, what they did and why they left. That could change with this discovery. There are already 111 known pile-dwelling settlements in the Alps region, including 56 in Switzerland, dating back to 50000 BCE and all have been granted World Heritage Site status to protect them and their artifacts. That will probably be extended to Lake Lucerne’s newly found Atlantis. | https://mysteriousuniverse.org/2021/05/prehistoric-lost-village-found-on-the-bottom-of-switzerlands-lake-lucerne/ |
We approach every project as a partnership. We call that the Robins & Morton Building Forward® approach. It is a formal process that engages everyone on the project team, reinforcing the commitment to deliver exceptional results. Building Forward empowers individuals at every level, fosters inclusion, promotes sustainability and drives innovation.
Building Forward brings Robins & Morton’s culture of caring about our clients, team members, trade contractors and communities to the forefront in every aspect of our company, holding us accountable to carry that culture forward. Building Forward’s guiding tenets–Collaboration, Continuous Improvement, Leadership Development and Creating a Learning Culture–and the integration of Lean tools and practices reinforce our Values and drive us to become better in everything we do.Learn More About Building Forward
At Robins & Morton, we’re building something great. We’re building to make a difference. From budgets and timelines, to communities and relationships, we pursue big ideas, while concentrating on the smallest details.
As one of Glassdoor's Best Places to Work, we’re constantly learning and continuously improving. We build each other up and together we’re building a legacy. | https://www.robinsmorton.com/ |
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