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The Griffin is a mythical beast with the body of a lion and the head of an eagle. Griffins came into Greek mythology as guardians of the treasures of Apollo. In Christian art, they functioned originally as symbols of Satan but later were used to symbolize the union of Christ's divine and human natures (Impelluso, 374).
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A late example of the satanic symbolism is outside St. Anthony's basilica, where two huge griffins grasp men and beasts in their paws (second picture at right). Perhaps the most notable example of the christological symbolism is in Dante's Purgatorio used the Griffin to represent Christ in the (cantos 29:106-114, 31:118-26).
Griffins also appear in heraldry. In the first picture on the right, of a broken fragment from a French monastery, the griffin could have been intended either as a symbol of Christ or as a heraldic reference to a sponsor.
Prepared in 2018 by Richard Stracke, Emeritus Professor of English, Augusta University. | https://christianiconography.info/griffin.html |
Dry socket (alveolar osteitis) is a wound healing complication that can occur following teeth extractions if the initial blood clot is lost. This results in exposed bone in the socket devoid of normal healing tissues, hence the name “dry socket.” It usually occurs three to five days after an extraction and is characterized by a sudden increase in severe and throbbing pain. Dry socket is treated by temporarily packing the site with eugenol, antibiotics, and oral rinses. As the socket forms a new layer of healing tissue, the pain gradually subsides and, finally, the socket slowly fills in over the next 2-3 months.
The risk for dry socket increases in patients who smoke after teeth extractions, vigorously rinse too early, spit, or use a straw to drink within the first 24 hours—all of which can disturb the initial blood clot. Another major risk factor for developing dry socket is traumatic surgical techniques, such as tearing the gum tissue, aggressive drilling of the bone, and excessive manipulation of the extraction socket, which, ultimately, results in devitalized tissue with poor blood supply.
While the possible incidence of dry socket is between 1-3%, we have experienced no dry sockets after performing more than 150,000 extractions over the past 20 years.
Here are our secrets to avoiding dry socket after teeth extractions:
•Non-traumatic surgical techniques: An experienced oral surgeon can extract teeth using non-invasive or minimally-invasive techniques. This means no gum tissue flap or minimal gum tissue flap. No removal of the bone or minimal removal of the bone. The use of copious amounts of irrigation, gentle handling of the tissues, and the removal of teeth with ease. There is an old saying, “Do less to the body, and the body will do less to you!”
•Avoid smoking following an extraction: Smoking creates suction in the mouth that can dislodge the blood clot. It also directly inhibits the normal healing physiology.
•Avoid rinsing or brushing on the evening of an extraction. Any rinsing or brushing immediately following a tooth extraction can cause loosening or dislodging of the blood clot leading to a dry socket. Do not rinse or brush until the day after the extraction. Then rinse gently for the next 1-2 days and more vigorously in the following days.
•Do not use a straw in the first 24 hours. The use of a straw can also cause suction and dislodge the blood clot. To drink, simply sip from a glass.
•Do not spit within the first 24 hours. With blood and saliva accumulating in the mouth following an extraction, you may be inclined to spit it out. This action, again, can disrupt the organizing blood clot and cause it to loosen. Do not spit; instead, let the accumulated blood and saliva drool down and wipe it gently with a gauze or tissue.
•Keep biting on the gauze with firm pressure until bleeding stops. Constant and firm pressure helps to slow down bleeding following teeth extractions and stabilizes the formed blood clot. The gauze should remain in place for at least 30-45 minutes before changing it for a new one; continue using the gauze until bleeding stops completely. | https://www.facialart.com/2017/07/avoid-dry-socket-teeth-extractions-2/ |
In Relationship-Rich Education, Felten and Lambert demonstrate that for relationships to be central in undergraduate education, colleges and universities do not require immense resources, privileged students, or specially qualified faculty and staff. All students learn best in an environment characterized by high expectation and high support, and all faculty and staff can learn to teach and work in ways that enable relationship-based education. Emphasizing the centrality of the classroom experience to fostering quality relationships, Felten and Lambert focus on students' influence in shaping the learning environment for their peers, as well as the key difference a single, well-timed conversation can make in a student's life. They also stress that relationship-rich education is particularly important for first-generation college students, who bring significant capacities to college but often face long-standing inequities and barriers to attaining their educational aspirations.
Drawing on nearly 400 interviews with students, faculty, and staff at 29 higher education institutions across the country, Relationship-Rich Education provides readers with practical advice on how they can develop and sustain powerful relationship-based learning in their own contexts. Ultimately, the book is an invitationand a challengefor faculty, administrators, and student life staff to move relationships from the periphery to the center of undergraduate education.
Product Details
|ISBN-13:||9781421439365|
|Publisher:||Johns Hopkins University Press|
|Publication date:||11/03/2020|
|Pages:||208|
|Product dimensions:||5.50(w) x 8.50(h) x 0.75(d)|
|Age Range:||18 Years|
About the Author
Table of ContentsForeword
Acknowledgments
Introduction
Chapter 1. Visions of the Possible
Chapter 2. Why Is This So Hard?
Chapter 3. Making Relationships a Cultural Priority
Chapter 4. Creating Relationship-Rich Classrooms
Chapter 5. Rich Relationships Everywhere
Chapter 6. Mentoring Conversations
Conclusion. The Future Is Relationship Rich
Postscript
Notes
Index
What People are Saying About This
"This is the right book for a challenging time. Whether on campus or online or somewhere in between, relationships matter, perhaps now more than ever. In this wonderful book, Felten and Lambert remind us of that truth and show us practical examples of relationship-rich environments for students, faculty, and staff."
"As our country becomes more diverse and our institutions serve the new majorityfirst generation students, students of color, and/or low-income studentscolleges and universities must learn how to build trusted relationships that demonstrate authentic caring, respect, understanding, validation, and love. Relationship-Rich Education provides guidelines for institutions to follow to ensure success for all students."
"Anyone who works on a college or university campusadministrators, faculty, and staffwill come away from this book with fresh inspiration to form supportive and meaningful relationships with students. Readers will also find here a trove of creative, practical strategies for achieving that goal."
"This book takes an innovative approach to student success interventions, focusing on the essential role of relationships in shaping student experience and long-term success. The book includes numerous and detailed examples of how to create relationship-rich environments and incorporates the voices of faculty, staff, administrators, and students to bring its big ideas to life."
"Full of numerous examples of enacting relationship-rich environments, this book marshals a broad range of evidence to make a coherent argument about the importance of relationships while offering specific ways in which they can be enhanced at an individual, departmental, and institutional level. Relationship-Rich Education will resonate with higher education practitioners."
"Education luminaries Peter Felten and Leo M. Lambert challenge us never to forget that undergraduate education is at heart a relational enterprise. Relationship-Rich Education offers a cogent practitioner's guide to the art of teaching and mentorshipand a stern challenge to institutional leaders to prioritize and celebrate relationship-rich cultures. A game-changer in higher education."
"At a time of unprecedented transformation, Felten and Lambert demonstrate why the future of higher education must be grounded in the creation of welcoming campus communities that encourage a sense of belonging. They offer a compelling, insightful guide to fostering relationship-rich undergraduate education and fulfilling the burgeoning equity mandate at institutions of all types."
"The content of this impressively researched book has the potential to transform institutional culture. The voices of these students grabbed me in powerful ways, enabling me to understand more deeply the value of rich relationships to undergraduate success across institutional types and student status." | https://www2.barnesandnoble.com/w/relationship-rich-education-peter-felten/1136509530?ean=9781421439365 |
IU composition majors at all degree levels are invited to submit orchestral works to be considered for the annual New Voices for Orchestra concert. The 2019 concert will be Wednesday, November 20 with one of the Jacobs School's large orchestras and will be conducted by David Dzubay.
Eligibility:
- IU composition majors who will be enrolled full-time during fall semester or who graduated within one semester; in the latter case, the composer must arrange to be in Bloomington to attend a minimum of two rehearsals in addition to both dress rehearsals.
- Works must have been composed or substantially revised and finalized while enrolled at IU and while working with a composition faculty teacher.
- Your teacher must approve of your submission by emailing the other composition faculty (ask them to do so).
Duration limit: 15 minutes (but under 10 is preferred)
Instrumentation maximum: 3333(doublings ok) - 4331 - T+4, harp, piano - strings. If your piece varies from this, check with your teacher and Professor Dzubay. No concertos.
TIMELINE
July 15 (12:00 noon): Deadline for submission of score (PDF) and recording (mp3, required).
Submission procedure: upload your score to the composition department Submissions folder at IU Box. Use this filename format: NewVoices_<last name>_<title>.pdf (or ".mp3")
Example: NewVoices_LastName_TitleOfPiece.pdf; NewVoices_LastName_TitleOfPiece.mp3
(Pro tip: use your IU-provided-freely Acrobat Professional to “Save as…reduced size PDF”)
August 1: Announcement of selections
August 15: Deadline for sample parts (PDF) to Profs. Travers & Fleezanis and to PED (violin 1, flute 1, trumpet 1, percussion 1)
September 15: Deadline for complete set of parts (PDF) and final/corrected score (PDF) to PED
(Since this is for performance by a major ensemble of the JSOM, PED librarian Cynthia Stacy is generously willing to have PED print your scores and parts; scores should be formatted for 11x17 and parts should be formatted for 10x13; be sure to size your music correctly with these final printing sizes in mind). | https://musintra.sitehost.iu.edu/departments/academic/composition/student-activity/new-voices.html |
Q:
How to declare and use static enum in Java
I googled around SO about my question, but does not find the relevant example that matches my situation.
public class Game{
static enum Tile
{
static //Syntax error, insert "Identifier" to complete EnumConstantHeader
{
DIRT = new Tile("DIRT", 1); //Cannot instantiate the type Game.Tile
GRASS = new Tile("GRASS", 2);
ROCK = new Tile("ROCK", 3);
EXIT = new Tile("EXIT", 4);
PLAYER = new Tile("PLAYER", 5);
PLAYER_LEFT = new Tile("PLAYER_LEFT", 6);
PLAYER_RIGHT = new Tile("PLAYER_RIGHT", 7);
//For all above declared fields, I am getting this compile time errors :
/*
Multiple markers at this line
- Cannot instantiate the type
Game.Tile
- DIRT cannot be resolved to a
variable
*/
Tile[] arrayOfTile = new Tile[8];
arrayOfTile[0] = EMPTY;
arrayOfTile[1] = DIRT;
arrayOfTile[2] = GRASS;
arrayOfTile[3] = ROCK;
arrayOfTile[4] = EXIT;
arrayOfTile[5] = PLAYER;
arrayOfTile[6] = PLAYER_LEFT;
arrayOfTile[7] = PLAYER_RIGHT;
$VALUES = arrayOfTile;
}
}
}
In my case I have declared the enum as depicted above. But I am receiving lots of Compile errors which I have inserted as comments in the above code.
Can anybody point me in the right direction to solve this please?
A:
I would follow the standard enum tutorial
http://docs.oracle.com/javase/tutorial/java/javaOO/enum.html
Have a look at the example for Planet
public enum Planet {
MERCURY (3.303e+23, 2.4397e6),
VENUS (4.869e+24, 6.0518e6),
EARTH (5.976e+24, 6.37814e6),
MARS (6.421e+23, 3.3972e6),
JUPITER (1.9e+27, 7.1492e7),
SATURN (5.688e+26, 6.0268e7),
URANUS (8.686e+25, 2.5559e7),
NEPTUNE (1.024e+26, 2.4746e7);
private final double mass; // in kilograms
private final double radius; // in meters
Planet(double mass, double radius) {
this.mass = mass;
this.radius = radius;
}
There is a values() method which is defined for you. You don't need to do that yourself.
| |
Analysis of data from darkside and eclipse observations of Io by the NIMS and SSI instruments show that the South Volund hot spot is a manifestation of high temperature active silicate volcanism. The NIMS data are fitted with a two temperature model (developed from modelling terrestrial lavas) which yields a better fit to the data than a single temperature fit. The multispectral color temperatures obtained from NIMS are compared with the brightness temperatures obtained from the SSI instrument, and show excellent agreement for the hotter of the two components fitted to the NIMS data. The two components might correspond to a cooled crust which has formed on the surface of an active flow or lava lake, at a temperature of approximately 450 K, and covering an area of about 50 km2, and a hotter and much smaller component, at a temperature of approximately 1100 K and an area of less than 0.1 km2. The hot component implies the existence of cracks in the surface crust of a flow or lake through which the hot interior radiates, a hot vent area, or breakouts of lava forming new flow lobes. The ratio of these areas is consistent with the crack-to-crust ratio of some lava flows and lava lakes on Earth. | https://arizona.pure.elsevier.com/en/publications/temperature-and-area-constraints-of-the-south-volund-volcano-on-i |
Abstract:The sharp rise in international students into Ireland has provided colleges with a number of opportunities but also a number of challenges, both at an institutional and individual lecturer level and of course for the incoming student. Previously, Ireland’s population, particularly its higher education student population was largely homogenous, largely drawn from its own shores and thus reflecting the ethnic, cultural and religious demographics of the day. However, over the twenty years Ireland witnessed considerable economic growth, downturn and subsequent growth all of which has resulted in an Ireland that has changed both culturally and demographically. Propelled by Ireland’s economic success up to the late 2000s, one of the defining features of this change was an unprecedented rise in the number of migrants, both academic and economic. In 2013, Ireland’s National Forum for the Enhancement for Teaching and Learning in Higher Education (hereafter the National Forum) invited proposals for inter-institutional collaborative projects aimed at different student groups’ transitioning in or out of higher education. Clearly, both as a country and a higher education sector we want incoming students to have a productive and enjoyable time in Ireland. One of the ways that will help the sector help the students make a successful transition is by developing strategies and polices that are well informed and student driven. This abstract outlines the research undertaken by the five colleges Institutes of Technology: Carlow; Cork; Tralee & Waterford and University College Cork) in Ireland that constitute the Southern cluster aimed at helping international students transition into the Irish higher education system. The aim of the southern clusters’ project was to develop a series of online learning units that can be accessed by prospective incoming international students prior to coming to Ireland and by Irish based lecturing staff. However, in order to make the units as relevant and informed as possible there was a strong research element to the project. As part of the southern cluster’s research strategy a large-scale online survey using SurveyMonkey was undertaken across the five colleges drawn from their respective international student communities. In total, there were 573 responses from students coming from over twenty different countries. The results from the survey have provided some interesting insights into the way that international students interact with and understand the Irish higher education system. The research and results will act as a model for consistent practice applicable across institutional clusters, thereby allowing institutions to minimise costs and focus on the unique aspects of transitioning international students into their institution.
Keywords: Transitions, Digital, International, supportProcedia PDF Downloads 174
3 Governing Urban Water Infrasystems: A Case Study of Los Angeles in the Context of Global Frameworks
Authors: Joachim Monkelbaan, Marcia Hale
Abstract:Now that global frameworks for sustainability governance (e.g. the Sustainable Development Goals, Paris Climate Agreement and Sendai Framework for Disaster Risk Reduction) are in place, the question is how these aspirations that represent major transitions can be put into practice. Water ‘infrasystems’ can play an especially significant role in strengthening regional sustainability. Infrasystems include both hard and soft infrastructure, such as pipes and technology for delivering water, as well as the institutions and governance models that direct its delivery. As such, an integrated infrasystems view is crucial for Integrative Water Management (IWM). Due to frequently contested ownership of and responsibility for water resources, these infrasystems can also play an important role in facilitating conflict and catalysing community empowerment, especially through participatory approaches to governance. In this paper, we analyze the water infrasystem of the Los Angeles region through the lens of global frameworks for sustainability governance. By complementing a solid overview of governance theories with empirical data from interviews with water actors in the LA metropolitan region (including NGOs, water managers, scientists and elected officials), this paper elucidates ways for this infrasystem to be better aligned with global sustainability frameworks. In addition, it opens up the opportunity to scrutinize the appropriateness of global frameworks when it comes to fostering sustainability action at the local level.
Keywords: Governance, Transitions, global frameworks, infrasystemsProcedia PDF Downloads 124
2 Analyzing the Factors That Influence Students' Professional Identity Using Hierarchical Regression Analysis to Ease Higher Education Transition
Authors: Rosalía Cascón Pereira, Alba Barbara-i-Molinero, Ana Beatriz Hernandez Lara
Abstract:Our general motivation in undertaking this study is to propose alternative measures to lighten students experienced tensions during the transitions from high school to higher education based on the concept of professional identity strength. In order to do so, we measured the influence that three different factors external motivational conditionals, educational experience conditionals and personal motivation conditionals exerted over students’ professional identity strength and proposed the measures considering the obtained results. By using hierarchical regression analysis we addressed this issue, across disciplines and bachelor degrees, allowing us to gain also deeper insight into first-year university students PID. Our findings suggest that students’ from the different disciplines are influenced by personal motivational conditionals; while students from sciences are also influenced by external motivational conditionals. Based on the obtained results we propose three different alternative educational and recruitment strategies which aim to increase students’ professional identity strength and reduce the tensions generated during high school-university transitions. From this study theoretical contributions regarding the differences in the influence of these factors on students from different bachelor degrees arise; and practical implications for universities, derived from the proposed strategies.
Keywords: Higher Education, Transitions, Strategies, professional identityProcedia PDF Downloads 33
1 Exploring Transitions between Communal- and Market-Based Knowledge Sharing
Authors: Belbaly Nassim, Benbya Hind
Abstract:Markets and communities are often cast as alternative forms of knowledge sharing, but an open question is how and why people dynamically transition between them. To study these transitions, we design a technology that allows geographically distributed participants to either buy knowledge (using virtual points) or request it for free. We use a data-driven, inductive approach, studying 550 members in over 5000 interactions, during nine months. Because the technology offered participants choices between market or community forms, we can document both individual and collective transitions that emerge as people cycle between these forms. Our inductive analysis revealed that uncertainties endemic to knowledge sharing were the impetus for these transitions. Communities evoke uncertainties about knowledge sharing’s costs and benefits, which markets resolve by quantifying explicit prices. However, if people manipulate markets, they create uncertainties about the validity of those prices, allowing communities to reemerge to establish certainty via identity-based validation. | https://publications.waset.org/abstracts/transitions-related-abstracts |
Experiments combining different groups or factors are a powerful method of investigation in applied microbiology. ANOVA enables not only the effect of individual factors to be estimated but also their interactions; information which cannot be obtained readily when factors are investigated separately. In addition, combining different treatments or factors in a single experiment is more efficient and often reduces the number of replications required to estimate treatment effects adequately. Because of the treatment combinations used in a factorial experiment, the degrees of freedom (DF) of the error term in the ANOVA is a more important indicator of the ‘power’ of the experiment than simply the number of replicates. A good method is to ensure, where possible, that sufficient replication is present to achieve 15 DF for each error term of the ANOVA. Finally, in a factorial experiment, it is important to define the design of the experiment in detail because this determines the appropriate type of ANOVA. We will discuss some of the common variations of factorial ANOVA in future statnotes. If there is doubt about which ANOVA to use, the researcher should seek advice from a statistician with experience of research in applied microbiology. | https://research.aston.ac.uk/en/publications/statnote-11-the-two-factor-analysis-of-variance |
Climate Science Glossary
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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.
Posted on 29 September 2020 by Guest Author
The enjoyable lull in Atlantic tropical cyclone activity over the past week may come to an end this weekend, when a large low-pressure system that is expected to develop in the western Caribbean has a 50% chance of spawning a tropical depression, according to the National Hurricane Center.
A large, complex area of low pressure called the Central American Gyre (CAG) will develop in the western Caribbean late this week, generating heavy rain as it moves slowly west-northwest. CAGs tend to develop near the beginning and end of the Atlantic hurricane season, and they can sprawl over hundreds of miles. They are notoriously long-lasting and slow-moving, making them prodigious rain producers. For more background, Phillipe Papin is an expert on CAGs (click here to animate his tweet, shown right), and he maintains an excellent CAG forecast page.
As smaller-scale vortexes spin around the CAG, one or more of them can consolidate into a tropical cyclone and eventually break away from the gyre. That outcome can happen in either the Atlantic or the Pacific. For example, on May 31, the first named storm of the Eastern Pacific hurricane season, Tropical Storm Amanda, developed from a CAG, and it made landfall on the south coast of Guatemala later that day. In October 2018, after a week of gestation, a disturbance on the north end of a CAG became a tropical depression in the western Caribbean. Three days later, that depression had detached from the gyre and barreled into the Florida Panhandle as mighty category 5 Hurricane Michael.
The exact location and timing of any tropical cyclones that may develop from this week’s CAG cannot yet be predicted with much probability of success. If the CAG does manage to spawn a hurricane in the coming week, the most likely location for a storm would be in the waters of the extreme northwest Caribbean, near western Cuba and the northeast Yucatan Peninsula. It is more likely that a tropical depression or weak tropical storm would form farther to the south, as predicted by the 6Z Tuesday run of the GFS Ensemble Forecast System (Figure 1).
In that figure, predicted locations of centers of low pressure are shown as orange numbers in millibars, with the leading “10” or “9” omitted, depending on whether the low’s central pressure were above or below 1000 mb. For example, a 999-mb low pressure center will be displayed as “99”, and a 1000-mb low pressure system will be displayed as “00”. In blue numbers, with the leading “10” left off, are the predicted locations of centers of high pressure. For example, a 1020-mb high pressure system will be coded as “20”. Each of the 31 forecasts from the individual member forecasts generated a different location and central pressure for major high- or low-pressure systems. The color-coding is a measure (in standard deviations) of ensemble spread – the difference in pressure between the ensemble mean and the individual member. Six ensemble members predicted a hurricane-strength system with a pressure of 985 mb or lower in the western Caribbean on Saturday. These were color-coded orange, showing a high spread from the ensemble mean, since their central pressure differed greatly from the mean predicted pressure.
Figure 2. Departure of sea surface temperature (SST) from average on September 29. SSTs were approximately 1.0 degrees Celsius (1.8°F) above average in the Caribbean. (Image credit: Tropical Tidbits)
Even busy hurricane seasons have extended lulls
Even the busiest hurricane seasons have lulls. For example, during the record-busy 2005 Atlantic hurricane season, Irene was named on August 7, but the next storm, Jose, didn’t get named until August 22.
Lulls like these are usually caused by sinking air over the tropics, leading to drying, high pressure, and reduced odds of tropical storm formation. Sinking air is caused by an unfavorable state of the Madden Julian Oscillation (MJO), or by the suppressed phase of an atmospheric disturbance called a convectively coupled Kelvin wave (CCKW). The MJO is a pattern of increased thunderstorm activity near the equator that moves around the globe in 30 to 60 days; odds of tropical cyclone formation increase when the MJO is strong and located in the proper location, but typically decrease for ocean basins not in the active portion of the MJO. Similarly, a CCKW is a large but subtle atmospheric impulse, centered on the equator, that rolls eastward at 30-40 mph, with showers and thunderstorms along its forward flank. On either side of this center of action, sinking air, high pressure, and reduced odds of tropical storm formation typically occur.
Passage of the suppressed phase of a CCKW and an unfavorable MJO have been acting to dampen Atlantic tropical cyclone activity since last week, but that situation will change by mid-October. With ocean temperatures still much above average (Figure 2) and a season that has a proven track record for spitting out large numbers of named storms, we likely will see at least three named storms form in October. As discussed above, there is even a chance of one spinning up this weekend in the western Caribbean, despite the relatively unfavorable MJO.
*The amount of rising or sinking air can be inferred from the 200 mb velocity potential (VP) departure from average (also called the anomaly). Negative 200 mb VP anomalies mean that upper-level winds at the 200 mb level are diverging, causing rising air from below to replace the air diverging away at high altitudes. This rising air helps nurture thunderstorm updrafts, and favors low pressure and increased chances of tropical cyclone formation. Conversely, positive 200 mb VP anomalies imply converging air aloft, where sinking air, high pressure, and dry conditions will be unfavorable for tropical cyclone formation. In this plot, negative 200 mb VP anomalies (divergence) are cool-colored contours (the scale shows the departure from average in standard deviations); positive 200 mb VP anomalies (convergence) are warm-colored contours. | |
HEALTH INFORMATION SYSTEMS
The Health Information Systems major is shared between the departments of Business, Economics, Health, and Computer Science. This program is designed to develop skills and a knowledge base that will allow students to pursue careers in the health and information technology, including informatics, both here in Maine and elsewhere. The focus of the concentration is to develop specific competencies, knowledge and business, programming and computer skills that will facilitate career progression in health information systems sector, including the State Government, State Agencies and the Private sector. For a full description, visit the UMF catalog.
How do I explore Health Information Systems at UMF?
There are many ways to explore a major. You could:
- Review the webpage for this major.
- Talk to faculty members in the major. Ask about their career path.
- Sit in on a class in this major. Choose a class of interest and contact the faculty member to find out which day might be best to drop in on. If you have access to myCampus, click here to go to Schedule Planner to view classes.
- Talk with upperclass students in the major. They can give you insights into the courses you will take and professors who will instruct you. Just remember, their reasons for liking a major may be different from your own. Ask your advisor, your CA or other UMF staff to help you find someone in the major.
- Enroll in one of the following courses:
- COS 140 Introduction to Computer Science
- HEA 123 Introduction to Community Health
- Get involved with a Club & Organization related to the major (for example, Computer Club or Health Club).
- Volunteer or intern with an organization that is aligned with this major. Contact Joe Austin at The Partnership for Civic Advancement, or Career Counselors Stephen Davis or Cyndi McShane to discuss opportunities.
- Try a Job Shadow or Informational Interview. Contact Stephen Davis or Cyndi McShane for more information.
- Make an appointment to talk to a Career Counselor (Steve or Cyndi) or Academic Advisor (Lori Soucie) about the major.
What can I do with this major?
Learn more about the major using this resource maintained by the University of North Carolina at Wilmington: http://www.uncw.edu/career/WhatCanIDoWithaMajorIn.html
Can I minor in Health Information Systems? Are there related majors at UMF?
UMF has a minor in Computer Science, Community Health, Business Economics, and many other choices. Click here for more information. Majors related to Health Information Systems include Business Economics, Community Health, and Computer Science.
What kind of jobs have UMF graduates obtained with this major?
Graduates have obtained positions as an Assistant Billing Manager at Massachusetts General Hospital, Project Coordinator at Maine Health, Population Health Specialist, and Software Integration Coordinator at OrderLogix.
This academic offering is ideal for those who want to work for state or local public health agencies, managed care organizations, pharmaceutical companies, international health agencies, federal health programs, healthcare providers, or work as IT professionals in jobs such as: Project Manager, Information Systems Analyst, Clinical Informaticist, Clinical Application Manager, Information Systems Trainer Programmer / Analyst, Chief Information Officer, and others.
What other career paths can I pursue?
Other career paths include Medical Records Technician, Health Educator, Occupational Health & Safety Technician, and many more. Talking to faculty in the major or a career counselor can provide you with more information about a variety of career paths associated with this major.
How do I declare this major?
The first step is to communicate with the contact person for this major: Dr. Gail Lange, Brinkman House, [email protected], 207-778-7391.
To apply to the major, complete a change of major form (available in Merrill Center or any academic office). | http://www2.umf.maine.edu/advising/about/explore-majors-at-umf/health-information-systems/ |
Monthly Archives: March 2015
The Countywide Vision Environment Element Group on Wednesday prioritized what additional research is needed to develop a comprehensive approach to the preservation and conservation of habitat for threatened and endangered species in San Bernardino County.
The Group selected as its next steps:
The creation of a countywide inventory of conservation lands in the county and establishment of a system for tracking new conservation land acquisitions
The completion of a detailed analysis of where threatened and endangered species live in comparison to known conservation lands to identify any gaps in protection of those focal species
This was the fourth time in the past year that the Group consisting of experts in environmental protection, land use, infrastructure, utilities, business and regulatory agencies has met to develop a plan for how to best balance habitat preservation and conservation with expected population and economic growth.
Dudek, an environmental and engineering consulting firm hired last year by San Bernardino Associated Governments (SANBAG), has been assisting the Group with the creation of a framework and plan for developing a regional conservation approach.
The additional research tasks chosen by the Group were among the potential next steps suggested by Dudek. The Group decided it needed the information from the countywide conservation lands inventory and habitat gap analysis to better understand the benefits and limitations of possible conservation approaches.
The Group will request financial assistance from the County of San Bernardino and SANBAG to complete the research.
In December and January, the Group reached agreement on a set of policy and biological principles to guide future preservation and conservation of habitat for threatened and endangered species in a way that is beneficial for the health of the environment, the economy, and the citizens of San Bernardino County.
Last year, Dudek staff collected information about existing conservation efforts throughout the county. They provided the Environment Element Group with their insights from their interviews of officials with cities and towns, the County, regional planning and infrastructure entities, environmental protection groups, resource conservation districts, state and federal regulatory and resource agencies, including:
Some municipalities have addressed habitat conservation by designating lands as open space, adopting hillside protection ordinances, and preparation of individual habitat conservation plans.
State and federal wildlife agencies would like to see a connected and comprehensive approach to habitat conservation.
Anyone with valuable insights into conservation planning efforts anywhere in the county is encouraged to contact Josh Lee at SANBAG – [email protected].
Eleven middle schools in San Bernardino and Riverside counties will attend the sixth annual Auto Club Speedway STEM Day on March 20 as part of the Auto Club 400 Weekend. The STEM Day event will be held at the speedway beginning at 9 a.m.
More than 500 students are expected to participant in the event, which will feature special guest speakers Daniel Suarez, a NASCAR Xfinity Series Driver; Dakota Sun, National Hot Rod Association Sportsman Motorcycle National Event Champion; and Ivan “Iron Man” Stewart, an off-road racing legend.
Science, technology, engineering, and mathematics (STEM) are a foundation to the motorsports industry. Students will spend the day participating in a series of hands-on activities demonstrating how concepts are used in the sport of racing.
Students attending will receive a pair of reserved grandstand tickets to the Auto Club 400 race on March 22, courtesy of sponsor King Taco.
Participating schools – and their districts — include:
Almeria Middle School, Fontana Unified School District;
Big Bear Middle, Bear Valley Unified;
Cobalt Institute for Math and Science, Victor Valley Union High School District;
Grace Yokley Middle, Mountain View;
Kolb Middle, Rialto Unified;
Mesa View Middle, Yucaipa-Calimesa Joint Unified;
Ranchero Middle, Hesperia Unified;
Upland Junior High, Upland Unified;
Vanguard Prep, Apple Valley Unified;
Vineyard Junior High, Ontario-Montclair;
Vista Verde Middle, Val Verde Unified.
STEM Day is made possible with the funding from Alcoa Foundation; San Manuel Band of Mission Indians; Toyota Financial Services; John Elway’s Crown Toyota; Toyota Motor Sales; King Taco; and the Inland Empire United Way.
Educational partners teaming up with Auto Club Speedway include San Bernardino County Superintendent of Schools’ Alliance for Education; Chaffey College; Ontario-Montclair School District; San Bernardino County Superintendent of Schools; San Bernardino Community College District; San Bernardino Valley College; MESA Program; and University of California, Riverside.
The Inland Empire Economic Partnership recently recognized the leaders of more than two dozen Inland Empire governments and agencies at its Second Annual “Turning Red Tape to Red Carpet Awards” reception, 14 of them representing San Bernardino County and the Countywide Vision’s Regional Goal of establishing the county as a model in the state where local government, regulatory agencies and communities are truly business-friendly.
The IEEP, the region’s largest economic development organization, honored the cities, counties and agencies that came up with innovative ways to enhance job growth and the local economy despite an often-difficult regulatory environment. These are the San Bernardino County agencies, departments and people that have gone the extra yard to grow the economy.
Business Retention and Expansion
FINALISTS: The San Bernardino Community College District for far exceeding its goals of hiring local people to work on capital improvement projects; City of Redlands for an aggressive downtown improvement project that was accomplished without the use of the city’s general fund.
Sustainable and Green Development
WINNER: City of Rancho Cucamonga for an automation project for numerous city departments that puts vital services online for the first time, dramatically reducing the amount of paper and ink that must be used as well as the need to drive to city offices.
RUNNER UP: San Bernardino Associated Governments, for a regional plan to reduce greenhouse gases in compliance with state laws that brings simplicity and consistency for 21 cities in San Bernardino County.
OTHER FINALIST: San Bernardino Community College District, for alternative energy measures in construction, landscaping and energy consumption, along with other environmental strategies.
Real Estate Redevelopment and Reuse
FINALISTS: City of Ontario, for a downtown office building project the will provide jobs while maintaining the character of the area; City of Rialto, for its repurposing a blighted area and helping create that land into the site of a 718,000-square-foot logistics center.
Public-Private Partnership
RUNNER-UP: San Bernardino County Sheriff’s Department, which rallied other agencies to work with the promoters of the San Manuel Pavilion and other venues, achieving the twin goals of smooth operations and public safety.
Response to Globalization
WINNER: San Bernardino County Land Use Services Department, for using GIS technology to develop a computerized system that lets would-be developers, even developers in other countries, to self-search vacant land in the county.
Tales of Two Cities: Stories of Interagency Cooperation
WINNER: City of Rancho Cucamonga Library, for developing a program, in partnership with Riverside, Ontario and others, to establish new training parameters for a next generation of librarians in the Inland Empire.
RUNNER-UP: City of Fontana, for bringing other cities and agencies on board to solve issues relating to Interstate 10 interchange development, which helped Fontana redevelop some blighted areas.
OTHER FINALISTS: San Bernardino and Riverside counties, along with UCR and Los Angeles, for implementing the state’s Innovation Hub economic development project; The cities of Yucaipa and Calimesa, which work together on numerous projects despite being in two different counties.
Leadership in Public Service
RUNNER-UP: Kristen Riegel, the Supervising Hazardous Materials Specialist for the San Bernardino County Fire Prevention District. She has worked hard to ensure that businesses can operate with a minimal amount of government-imposed fees and still not compromise the environment or the safety of workers. Under her guidance, fees have come down for 20 percent of the businesses that are covered.
On March 6, the San Bernardino School District, in partnership with the City of San Bernardino, led a “Path to Success” field trip designed to excite junior high students about local options in higher education. Six hundred students from Richardson, Shandin Hills, Rodriguez, and King middle schools participated in the event.
The Art Institute, Valley College, and Cal State San Bernardino provided free campus tours and presentations. Omnitrans sponsored transportation for students between institutions on city buses and its sbX rapid transit service. Representatives from the bus agency were on hand to assist each group in navigating their routes.
The three schools are also participants in the Omnitrans GoSmart program, which offers students unlimited free bus rides with their student IDs. Funding for the discounted fare program comes from student fees and administrative sources.
| |
This page is a blog article in progress, written by David Tanzer. To discuss this article while it’s being written, visit the Azimuth Forum. Please remember that blog articles need HTML, not Markdown.
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We’re heading towards writing a simulator for a continuous deterministic Petri net, but lots of concepts are clamoring for attention along the way! In the first place, we need to understand the dynamic principle of these networks, which is captured by the “rate equation.” This is a differential equation, for which we did some preparatory work in the last article.
In a prior article, we introduced the basic model of stochastic Petri nets, through which discrete tokens flow, and which have transitions that fire according to a probabilistic model. Now we are starting to talk about continuous Petri nets, where the moving tokens are essentially treated as a fluid substance. These models are e
How do we pass from the one model to the other?
But before that, in this article I will address, in broad terms, the relationship between continuous Petri nets and the discrete random Petri nets which we described in a prior article.
In a word, the continuous model is derived from a limiting case of the discrete model, as populations get large, and that the determinism results from the “macroscopic” averaging of the mass of “microscopic” discrete random events. So the topics are well connected.
The model of a continuous, deterministic Petri net is actually derived from the more fundamental model of a discrete, stochastic Petri net, which we introduced in a previous blog article. Think of chemical reactions, for example. To a good approximation, we can view the amounts of the various substances as continuously varying magnitudes (and then view them as real-valued concentrations of particles per unit volume), and the processes as continually occurring, at various concentration-dependent rates. But in reality, at a detailed level, there is actually a discrete, integer valued number of each of the particles, and the reaction events take place by separate, discrete, random events.
In a stochastic process, different “runs” of the experiment will produce different sequences of events, and the collection of all possible sequences will be distributed according to a probability distribution. Each sequence of events will lead to a corresponding sequence of states of the system. At every point in time, therefore, there will be a distribution of possible states of the system. We can then take the expected value of the state at each point int time, and form the sequence of expected states for the stochastic process.
So, whereas the stochastic process consists of a non-deterministic collection of possible outcomes, all involving discrete integer states (in a stochastic Petri net, discrete population counts), the sequence of expected states is uniquely determined – a deterministic process – involving states with real-valued components – which result from taking the means of the integer-valued components.
Furthermore, under certain statistical assumptions (cite John’s recent paper), as the population counts get large, and the reaction rates increase, a law of large number will kick in, and the variations of the runs of the stochastic process around the mean will decrease (will cluster more tightly around the mean), so that the deterministic sequence of expected states will become a better and better approximation for the observed runs of the stochastic process.
Let’s illustrate with a physical example. Consider an apparatus where we have a winding spiral pipe, with rough and irregular inner walls. At the bottom it opens into a large jar, and at the top we pour a cup containing small pebbles. Each pebble eventually (bounces) makes its way from the top of the pipe to the bottom and into the jar, but due to the irregularities of friction, etc., there may be a substantial variation in the time that each pebble takes to traverse the pipe.
The events are the arrivals of the pebbles in the jar, and the state at each point we will take to be the number of pebbles in the jar. If we graph the state (the pebble count) as a function of time, it will be a non-decreasing function, with integer values, and integer jumps as pebbles enter the jar. But the expected number of pebbles in the jar, as a function of time, will be an increasing, continuous function.
(We suppose the pipe is wide in comparison to the pebble sizes, so there are no clogging or queueing effects.)
Now consider what happens if, say, we multiply by ten the number of pebbles that we release. The results of the process will still be stochastic, but the overall process, as recorded by the rising count of pebbles in the jar, will be smoother, and closer to the averaged out sequence of expected pebble counts.
In fact, by increasing the pebble counts within each run of the experiment, we are performing a kind of averaging there: the effects of the slower pebbles will be offset by the effects of the faster pebbles – the count in the jar reflects the aggregate effects of all the pebbles.
In the limiting process of a large number of pebbles, the behavior looks more like pouring sand into the pipe, which begins to look like a continuous fluid. The continuous fluid model is an even better approximation when we reach the scale of chemical reactions, which involve moles of chemical entities. As we pass to the theoretical limit, involving an infinite number of infinitesimal particles, we reach the fluid model for a continuous, deterministic process. | https://www.azimuthproject.org/azimuth/show/Blog+-+Petri+net+programming+%28part+4%29 |
Article & photo by Al Perry
Many people have some knowledge of northern lights (aurora borealis), but few have viewed or photographed the colorful, dancing lights in the sky. In less than six months, the northern lights (aurora borealis) can be viewed and photographed in the northern hemisphere. If you want to see them sooner, go to the southern hemisphere.
Northern (and southern) lights can occur all hours of the day, night and seasons of the year. However, northern lights are best viewed under cloudless, moonless, and dark skies in spring and fall at high latitude in the arctic. Active sunspots allow coronal mass ejections of charged particles from the sun to sometimes be directed toward the earth. A few of these fast moving charged particles strike our upper atmosphere and release a photon that we view as green, red, pink, blue, yellow and/or purple northern (or southern) light.
If you want to photograph the aurora borealis, travel to the arctic circle in September or March, take along warm boots, outer and inner wear, sturdy tripod, fast wide angle lens, low noise camera, and lots of patience. Aurora forecasts are not very reliable. If you are serious about photographing the aurora, plan on going out at 10 PM each evening and not coming back before 6 AM. It also helps to avoid big groups of other viewers/photographers as their head lights and LCD’s will often show in your images.
Active northern lights occur about once every ten to fifteen nights. Extraordinary northern lights occur about once every 45 days. For example, I had one very good night in Iceland during a 2 1/2 week visit. Clouds are more of a problem in Northern Europe than in North America. During 2 1/2 weeks in Alaska, I had two very good nights, one of which was extraordinary. Shown with this column is one of 4000+ images during one 8 hour evening. Each of the 4000 images is of similar quality, but all are different in content. For active northern lights, plan on an exposure time of about 10 seconds at f/2.8, 1600 ISO. People’s eyes are more receptive to green, which is the main color of northern lights. Your camera sensor can bring out all the colors of northern lights if properly exposed. Fairbanks, Alaska, is a good location due to its clear skies, relatively low airfares and winter maintenance of major road access to several good viewing areas. | https://rmowp.org/2013/08/24/photographing-northern-lights/ |
Did the US Marine Corps give up on a big ship-based surveillance drone too soon?
According to DefenseNews.com, “The U.S. Navy and Marine Corps both say they need expanded surveillance capabilities for a potential fight with China, but the Marines have cut bait on a big, ship-based system that some analysts say would make a big difference for both services… The Chief of Naval Operations' air warfare lead said earlier this month that every carrier strike group commander needs more surveillance, and he wants to find a way to get more pure intelligence, surveillance and reconnaissance drones flying off the flight decks of Navy ships as soon as possible.”
For more on this complex, still-unfolding story, please see the original article on DefenseNews.com. Lead photo: The Defense Advanced Research Projects Agency has been pursuing a ship-launched, long-range ISR drone capability in its Tactically Exploited Reconnaissance Node, or TERN surveillance drone (DARPA). Bell V-247 “Vigilant” Tiltrotor Unmanned Aerial System is a potential competitor for the Corps' MUX requirement. ( Photo courtesy/Bell Helicopter)
Thanks to CDR David Place (USN/Ret), davidplace47[at]gmail[dot]com, and Robin E. Alexander, President ATC, alexander technical[at]gmail[dot]com, for their assistance with this report, the background for which appeared in their # 20 - 19 - 19 SEPTEMBER 2020 edition of the UNMANNED SYSTEMS NEWS (USN).
David distributes the Unmanned Systems News (USN), a free, comprehensive newsletter in PDF format every week or two, as well as serial news flashes, from which this NREF news update was sourced. To be included in his distribution, simply send David a subscribe request to davidplace47[at]gmail[dot]com. | http://the-nref.org/content/did-us-marine-corps-give-big-ship-based-surveillance-drone-too-soon |
I’ve written “Part II. Dependency Resolution” for the sys-apps/portage documentation (installed with USE=doc enabled). The “Decision Making” chapter is posted here. There are also two more small chapters about package modeling and task scheduling.
Portage Dependency Resolution – Decision Making
Dependency Expression Evaluation
In terms of boolean logic, a dependency expression can
be expressed in disjunctive normal form (DNF), which is a
disjunction of conjunctive clauses. Each conjunctive clause
represents one possible alternative combination of dependency
atoms capable of satisfying the dependency expression.
Look-Ahead
When there are multiple combinations to choose from, a
look-ahead mechanism will choose an optimal combination to
satisfy constraints and minimize cost. The following package
states influence the cost calculation for a given combination:
- installed
- selected (for installation)
- not selected (for installation)
In cost calculations, virtual packages by themselves are
considered to cost nothing since they do not directly install
anything. It is the dependencies of a virtual package that
contribute to it’s cost.
Constraint Propagation
Combinations that include packages from the "installed" or
"selected" categories are less costly than those that include
packages from the "not selected" category. When a package
is chosen for installation, it transitions to the "selected"
state. This state change propagates to the cost calculations of
later decisions, influencing later decisions to be consistent
with earlier decisions. This feedback mechanism serves to
propagate constraints and can influence the modeling process
to converge on a more optimal final state.
Expanded Search Space
When evaluating virtual atoms, an expanded search space is
considered which recursively traverses the dependencies of
virtual packages from all slots matching a given virtual
atom. All combinations in this expanded search space are
considered when choosing an optimal combination to satisfy
constraints with minimal cost. | https://blogs.gentoo.org/zmedico/2008/04/ |
Over the past two decades, paramedics have been performing functions within local health systems beyond their traditional role of emergency transport. Examples include community paramedicine home visits and in-home palliative care. Many of these changes have happened in grassroots local systems without attention to high-level organizational and policy implications. In this exploratory project, we examine the changing roles of paramedics using the frameworks of integrated care.
Impact
The results of this study may help governments, healthcare leaders and the paramedic community understand key gaps in services and develop strategies to address them. This can inform the development of more integrated, patient-centred health and social services, and the appropriate organizational models and policy paradigms to support them.
Findings
Paramedics serve as flexible, adaptive capacity in health systems, filling an unmet need for health systems to be more responsive to local population needs. In collaboration with various care teams, paramedics perform unscheduled response functions and support prevention and primary care through clinical diagnostics and case-finding, targeting both broad, low-needs populations and more complex, high-needs populations. These findings support that integrated care systems can be enhanced by community-based services accessed through a single-point-of-entry, delivered by a generalist, flexible health workforce that is mobile in the community. This means reducing interprofessional barriers between health workers, fostering local organizational networks, allowing local control and experimentation, balancing standardization with flexibility and assessing value at a system level. | https://upstreamlab.org/project/role-of-paramedics-in-integrated-care/ |
I decided to investigate the possibility of a puzzle where each entry could be written as a combination of symbols for elements which would then be encoded to their atomic numbers.
First I created a database containing a plain dictionary and then I wrote modules to identify letter-pairs as elements and convert them into their atomic numbers or to identify single letters as elements and convert them. The plain dictionary became a dictionary which contained concatenated atomic numbers, the pertinent elements and the original words. Any words that did not lend themselves to such a treatment were discarded. The concatenated numbers were then converted to new “words” by changing 1 to A, 2 to B, etc. Each new “word” was scored from 1 to 100 by a formula derived from the length of the concatenated number compared to the length of the original word. It was now a simple matter to design a suitable grid and use Crossword Compiler to fill it using the scored word list. I increased the score of the fill until I was happy with the final grid.
I wanted a title that might hint at the entry method and the homophone for Watson seemed appropriate. Although Sherlock Holmes never exactly said “Elementary, my dear Watson” it is a well-known phrase. I also thought “What’s On?” suggested “What’s Going On Here?”
There have been a number of puzzles using elements and their atomic numbers and I was surprised to see AN Others by Radix and AN Other appear in the Magpie well after I had submitted my puzzle to the Listener. Roddy and I had independently set puzzles using a very similar idea but his had overtaken mine by the time it was published.
4 Responses to “Listener No 4341, What’s On?: A Setter’s Blog by Nod”
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4 May 2015 at 1:14 pm
I really enjoyed this and marvelled at the construction. The information given from intersecting entries was, to be sure, less useful than in a normal crossword, but that gave rise to a new challenge of its own, coupled with some really challenging clues. Thank you!
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4 May 2015 at 6:39 pm
I agree wholeheartedly with Olichant’s comment above. I found your puzzle tough, but rewarding; and the rather fuzzy help that intersections gave added interest and a different challenge. Thank you. | https://listenwithothers.com/2015/05/03/listener-no-4341-whats-on-a-setters-blog-by-nod/ |
Download Eu Enlargement Region Building And Shifting Borders Of Inclusion And Exclusion ebook PDF or Read Online books in PDF, EPUB, and Mobi Format. Click Download or Read Online button to EU ENLARGEMENT REGION BUILDING AND SHIFTING BORDERS OF INCLUSION AND EXCLUSION book pdf for free now.
The 2004 entry of 10 Central and Eastern European countries, along with Malta and Cyprus, into the EU has caused a huge shift in the EU's external boundaries. The socio-economic and political transformations that this shift has caused not only suggest new regional development opportunities, but also many potential problems and tensions. While the EU insists that enlargement will not signify 'new divisions', processes of inclusion and exclusion and the imposition of visa restrictions on non-EU citizens could pose obstacles to co-operation, conjuring fears of an emerging 'fortress Europe' that effectively divides the continent. Illustrated with case studies from Central and Eastern European border areas, this book examines capacities for region building across national borders in within the context of EU enlargement, synthesizing the various insights provided by local information and suggesting ways forward for the future development of the EU's 'Wider Europe' strategy.
Throughout history, the functions and roles of borders have been continuously changing. They can only be understood in their context, shaped as they are by history, politics and power, as well as cultural and social issues. Borders are therefore complex spatial and social phenomena which are not static or invariable, but which are instead highly dynamic. This comprehensive volume brings together a multidisciplinary team of leading scholars to provide an authoritative, state-of-the-art review of all aspects of borders and border research. It is truly global in scope and, besides embracing the more traditional strands of the field including geopolitics, migration and territorial identities, it also takes in recently emerging topics such as the role of borders in a seemingly borderless world; creating neighbourhoods, and border enforcement in the post-9/11 era.
Since 1991, post-Soviet political elites in Ukraine, Russia, and Belarus have been engaged in nation- as well as state-building. They have tried to strengthen territorial sovereignty and national security, re-shape collective identities and re-narrate national histories. Former Soviet republics have become new neighbours, partners, and competitors searching for geopolitical identity in the new "Eastern Europe", i.e. the countries left outside the enlarged EU. Old paradigms such as "Eurasia" or "East Slavic civilisation" have been re-invented and politically instrumentalized in the international relations and domestic politics of these countries. At the same time, these old concepts and myths have been contested and challenged by pro-Western elites. Borderlands into Bordered Lands examines the construction of post-Soviet borders and their political, social, and cultural implications. It focuses on the exemplary case of the Ukrainian-Russian border, approaching it as a social construct and a discursive phenomenon. Zhurzhenko shows how the symbolic meanings of and narratives on this border contribute to national identity formation and shape the images of the neighbouring countries as "the Other" thereby shedding new light on the role of border disputes between Ukraine and Russia in bilateral relations, in EU neighbourhood politics and in domestic political conflicts. Zhurzhenko also addresses 'border making' on the regional level, focusing on the cross-border cooperation between Kharkiv and Belgorod and on the dilemmas of a Euroregion 'in absence of Europe': Finally, she reflects the everyday experiences of the residents of near-border villages and shows how national and local identities are performed at, and transformed by, the new border. Borderlands into Bordered Lands was honored by the American Association for Ukrainian Studies as best book 2009/2010 in the field of Ukrainian history, politics, language, literature and culture. For more information, view: www.ukrainianstudies.org.
Want the straight dope on marijuana? This publication addresses one basic question: how can I find quality information on cannabis, amid all the bias and opinion? This monograph is divided into two volumes. This first volume centers on political, legislative, commercial and social developments relating to cannabis. Its core audience thus comprises policymakers, sociologists, historians, journalists and those involved in enforcement. The second volume is targeted at drugs professionals working in the fields of treatment, prevention and healthcare.
This is a volume of scholarly essays that asks the question of the meaning of Europe by examining certain aspects of Central European history as well as issues dealing with the EU's enlargement into Central Europe that not only have an impact on the EU's development, but that also contribute to bringing about a definition of Europe that reflects the values and aspirations of all its citizens. | http://newbooksinpolitics.com/political/eu-enlargement-region-building-and-shifting-borders-of-inclusion-and-exclusion/ |
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Name the structure present in fish which helps it to change direction? NCERT SCIENCE CLASS 6TH CBSE 2017Name the structure present in fish which helps it to change direction
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Fins are usually the most distinctive anatomical features of a fish. They are composed of bony spines or rays protruding from the body with skin covering them and joining them together, either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as seen in sharks. Apart from the tail or caudal fin, fish fins have no direct connection with the spine and are supported only by muscles. Their principal function is to help the fish swim. Fins located in different places on the fish serve different purposes such as moving forward, turning, keeping an upright position or stopping. Most fish use fins when swimming, flying fish use pectoral fins for gliding, and frogfish use them for crawling. Fins can also be used for other purposes; male sharks and mosquitofish use a modified fin to deliver sperm, thresher sharks use their caudal fin to stun prey, reef stonefish have spines in their dorsal fins that inject venom, anglerfish use the first spine of their dorsal fin like a fishing rod to lure prey, and triggerfish avoid predators by squeezing into coral crevices and using spines in their fins to lock themselves in place
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Good quality medicines are a prerequisite for a successful treatment. Post marketing surveillance is very crucial to ensure product quality and eliminating substandard products to be distributed and, consequently, ensure better patient clinical outcome. Hence, this study assesses quality of six brands of ciprofloxacin tablets marketed in Dessie, Ethiopia using in vitro quality control tests. Weight variation test, disintegration test, dissolution test and assay for the content of active ingredients was done according to United sates Pharmacopoeia, 2007. The percentage content of ciprofloxacin tablets were within the range of 90-110% and the disintegration time was found between 2.375- 6.31 minutes. In addition, ciprofloxacin tablets released more than 80% of the drug after 30 minutes. Hence, all brands of ciprofloxacin tablets met the quality control parameters as per United States Pharmacopoeial specifications.
Keywords: Ciprofloxacin; Quality; Substandard; Pharmacopoeial specifications
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Internship and Externship Opportunities for Current Law Students
Law students play a critical role in helping us to provide access to counsel and justice for low-income residents of the District of Columbia. Our neighborhood-based, service delivery model allows us to bring law students into low-income communities across the city to learn first-hand the myriad, daily challenges faced by residents living in poverty. Our interns/externs assist our staff attorneys in the field by conducting factual investigations and doing legal research across a variety of substantive areas. They also participate in client meetings, trial preparation, and community outreach activities. We also encourage all of our interns to take advantage of the professional networking and training opportunities available in Washington D.C. and the region.
How To Apply
New internship/externship classes begin every September (fall semester), January (spring semster) and May (summer program). Candidates should have excellent writing, factual and legal analytical skills; strong organizational skills; good communication and interpersonal skills to communicate effectively with clients, the public, and co-workers; and the ability to work collaboratively with others. Bilingual language skills are also highly valued. If you are interested in an internship with the Neighborhood Legal Services Program, see the open opportunities below or fill out our inquiry form below.
Current Internship Opportunities
NEW - Summer 2019 Legal Interns
What to Expect
Law students who have volunteered at NLSP have had the opportunity to work on a wide-range of legal projects and benefitted from substantive contact with our staff attorneys.
Maria Maldonado 2014 Women's Bar Association Founders Fellow writes about her experiences.
My fellowship at NLSP was an invaluable experience. Thanks to the generous contributions of the Women’s Bar Association Foundation, my summer internship cultivated and accelerated my professional growth. The work environment at NLSP was casual, yet productive and always offered high quality legal services. Ms. Turner Roberts and Mr. López took on mentoring roles and were, and still are, invested in my professional development. I became a much more sharp, polished, knowledgeable and empathetic legal advocate for the underserved. More importantly, I was able to help low-income communities and families get the legal services they need without charge, and little by little, empower these communities out of the harsh cycle of poverty.
Ashlee Lewis (Howard University School of Law '14):
"I served as the family law intern for Neighborhood Legal Services Program. I worked mostly under Keeshea Turner Roberts and Heather Hodges. While there I researched and analyzed family law issues including but not limited to custody and visitation, child support, domestic violence, divorce and paternity laws. I interviewed clients and participated in all phases of trial preparation. I drafted case summaries and composed research memorandums recommending arguments and positions for attorney usage in client letters and motions presentation. I made court appearances quite often assisting in any way I could including drafting points and questions to cross-examine on. I also designed a new publication/brochure of the services offered by Neighborhood Legal Services Program; it also provided the information on other like services offered in the city."
Schuaa Tajmuul (American University, Washington College of Law '12):
"The housing cases I worked on were very interesting and involved several, dfferent issues. In one case, a client had her rent subsidized by an independent group, and needed help understanding why she was behind on her rent It turned out that the group subsidizing her apartment had missed payments for several months. Another case involved a client who was threatened with eviction after someone picked a fight with her near her apartment complex, as her lease stated she would be evicted upon a physical altercation taking place on the rental property. We worked with her to determine that the conflict did not occur on the rental property and determined that due to that, the apartment complex could not hold her liable. These projects helped me develop skills in conducting legal research and writing, document review, and problem-solving. I was also involved in preparing direct and cross-examination questions for a hearing, as well as preparing the client for the court appearance. I additionally worked on several, other small matters through which I learned how to interview clients and develop working relationships with them. In fact, I was given the opportunity to present a case at a staff meeting where I discussed the merits of a case with the other attorneys and asked their advice as to whether this was a case we would be able to resolve. My experience at such meetings and with clients helped me develop confidence in speaking to others about the law." | http://www.nlsp.org/volunteer/opportunities-for-law-students |
According to the 2020 Open Doors Report on International Educational Exchange, more than 8,800 Bangladeshi students chose to study in the United States during the 2019/2020 academic year, in honor of International Education Week (IEW), November 16-20, 2020, a joint US Department of State and US Department of Education initiative. Bangladesh has reached a new all-time high, with a 7.1 percent growth over the previous year’s record (8,249 pupils), more than tripling since 2009. The United States Embassy in Dhaka has made promoting educational exchanges between Bangladesh and the United States a strategic priority.
Massachusetts Institute of Technology (MIT)
Information sessions and tours for prospective students have been canceled at MIT. The on-campus admissions office is likewise closed indefinitely, however, emails and phone calls are still being answered. Students whose education has been disrupted by COVID-19 have been promised that they will not be punished in the admissions process.
Through the summer of 2020, MIT will not host or sponsor any in-person K-12 student programs. Instead, efforts are being made to ensure that students and their families have access to all of the information they require about campus via an online delivery system.
Stanford University
Until further notice, the Stanford Office of Undergraduate Admission has been closed. However, applications are still being processed, and the office can be reached via email. All prospective student tours, activities, and information sessions have been canceled, and the Visitor Center has been closed till further notice.
Harvard University
For more information, international students who have been accepted to Harvard University should contact their academic department. Staff can be reached by email or phone while the admissions office is closed. There will be no cancellations of information sessions or tours. Visitas, Harvard’s weekend for accepted students, is now available online.
California Institute of Technology (Caltech)
Caltech will continue to admit international students, but all newcomers will have to follow self-quarantine requirements that apply to all travelers at first. Until further notice, all admission-related campus visit activities have been halted.
University of Chicago
At the University of Chicago, all on-campus activities have been canceled, and all classes are now offered online. Applicants will not be permitted to pay a visit to the university.
Princeton Universit
All of Princeton University’s lectures and classes are now delivered on the internet. Applicants will not be permitted to pay a visit to the university.
Cornell University
The Ithaca campus of Cornell University is largely closed, with only students living on-campus permitted to visit. All of the classes have been relocated to the internet.
The United States has more international students than any other country in the world. There are currently over one million of them. Let’s have a look at a few of the reasons for this.
Universities with the highest rankings in the world
The United States has a well-developed and high-quality tertiary education system. According to the 2017-2018 Times Higher Education World University Rankings, it has seven of the top ten universities in the world. In fact, the United States is home to 33 of the top 100 universities in the world [source: QS World Ranking 2019].
Unique curriculum and high-quality education
The United States’ educational system is well-known around the world. Students who attend US institutions benefit from a liberal arts education, which is one of the reasons they are so successful after graduation. This entails a concentration on areas beyond one’s major, such as mathematics, sciences, philosophy, history, and literature.
Language abilities in English
In the United States, English is the primary language spoken, and all courses are taught in English. You’ll be able to improve your talents and make yourself more appealing to companies. Most US campuses have English language programs tailored to international students, as well as study groups and mentoring programs where you may put your language skills to the test.
Research and development
The United States is a leader in scientific and creative innovation. Large research institutes, particularly in the United States, provide opportunities for students to work side by side with their instructors in the lab or workshop, applying what they’ve learned in class. Universities in the United States enthusiastically promote their faculty members’ fieldwork, and information on research possibilities for students is widely available.
Whatever your circumstances, one thing to remember is that studying abroad is still a viable option. The majority of universities, particularly in Europe, allow international students. In addition, visa application centers are beginning to reopen, and the vast majority of institutions have devised contingency plans in the event of further lockdowns, limitations, or travel bans.
It’s also important recalling that in a post-COVID world, the global view of the future is usually favorable. Governments have begun to respond to unexpected issues, and several safety precautions have been developed, such as mass testing and “track and trace” systems.
In terms of healthcare, the majority of European students will be covered in the event of an emergency. This isn’t always the case, though. Always check the laws of the country you’re visiting. Health insurance will almost certainly be required for anyone traveling into or out of the European Union. It’s also a good idea to find out if you’ll require a COVID-19 PCR test before you fly or when you get to your campus country.
Covid situation in both BD and the US
The UK
Bangladesh
Health Protocols
List of Approved Vaccines
To survive in Australia, students are urged to rely on family support, part-time work if possible, and their own funds. It’s worth noting that international students had to show that they could support themselves totally in their first year as part of their visa application. | https://www.apollointl.com.au/the-united-states-post-graduation-for-bangladeshi-students-covid-19-update/ |
Han Feng is a creative force known for her fashion accessories, ready-to-wear clothing line, and stage costumes. Based in New York and Shanghai, she continues to push the line between art and design. A highly refined aesthetic informs every element of her work. | https://shop.neuegalerie.org/products/wiener-carre-kimono |
LANCASTER – For now, the Lancaster City Council is holding off on a proposal to ban skateboarding and roller skating on The BLVD.
“I want to redraft this,” said Mayor R. Rex Parris, at a packed council meeting Tuesday.
The decision came after passionate testimony from more than a dozen residents both for and against a proposed ordinance and resolution that would have made it illegal to skateboard or roller skate on Lancaster Boulevard, between Sierra Highway and 10th Street West, as well as the surrounding side streets. (see the proposed “no skateboarding/ roller skating areas here“).
The City Attorney’s Office drafted the ordinance in response to complaints from residents that skateboarders posed dangers to pedestrians and drivers on The BLVD.
“Few things make me as crazy as getting out of my car and having a skateboarder whiz by me, no idea where he’s going, and I have to jump for my life,” said Diann Moskowitz.
Tenants of the Arbor Artist Lofts said skateboarders had disrupted their quality of life. They said the skateboarders were using the lofts’ parking area as a skate park and said the neighboring Pharmacy Boardshop had become a mecca for noisy skateboarders.
“I’ve had skateboarders living outside my window,” said Piper Coolidge. “I’ve had them throwing rocks at my sliding glass door.”
The ban was met with resistant by a contingent of skateboard supporters who attended Tuesday’s council meeting solely to oppose the ordinance.
Sharon Murray said skateboarding was a positive outlet for her son and many other local youths.
“If they don’t skateboard, they’re gonna do other things, and those things probably aren’t gonna be good things,” Murray said.
“These kids don’t have cars or drivers’ licenses…” said Nathan Morris of Pharmacy Boardshop. “It’s just a logical form of transportation for these kids.”
John Tietjen said his son rode a skateboard down The BLVD to get to school.
“By saying ‘no, you can’t go down Lancaster Boulevard,’ he’s got to go two or three blocks into areas that are less populated and crime could happen,” Tietjen said.
Also speaking against the ban were skaters, who felt they were being unfairly lumped in with the skateboarders.
“I get to my job by my skates,” said Muriah Chenoweth. “I need to go down the boulevard because not all the sidewalks are easy for me to actually skate on… [the ban] affects myself and also my derby team.”
“You have security, if they see somebody doing something that’s unsafe or inappropriate, they could be ticketed and asked to leave,” said avid skater Steven Blum. “I think that would be a better idea than a ban, where you ban everybody, especially the rollarskater who doesn’t seem to be causing any issues at all.”
The council listened to nearly an hour of testimony. Many speakers were granted more than the allotted three minutes speaking time to allow for interaction with the mayor and council members.
“What I am hearing is that there are concerns by the loft residents and they’re very valid concerns…” said Housing Authority Chair Kitty Kit Yee Szeto. “I’m hearing skateboarders need to use The Blvd to go to school or travel… if there is some way we can amend the ordinance or somehow redraft it to have restrictions on time and when it can be used, when the kids can use The BLVD to skateboard and when they can’t, I think that’s a good compromise for everybody.”
Parris instructed the city manager to set up a meeting between all parties that would be affected by a proposed skateboarding ban, including the sheriff’s deputy responsible for policing The BLVD, a Pharmacy Boardshop representative, a representative from the artists’ lofts and other stakeholders.
“Let’s figure out an ordinance that everybody can live with within the next 30 days,” said Parris, adding that he would insist all skateboarders wear helmets. | https://theavtimes.com/2012/07/24/council-holds-off-on-skateboard-ban/ |
Bulgaria is truly a land of outstanding beauty and astonishing heritage linking the East and the West, located on the northeastern portion of the Balkan Peninsula, in southeastern Europe and on the Black Sea. Bulgaria borders five other Balkan countries: Romania to the north /mostly along the Danube/, Serbia and Macedonia to the west, and Greece and Turkey to the south. Population of Bulgaria is approximately 8.8 million, of which about 1,2 million inhabitants live in the Capital of Sofia. With a territory of 110,994 square kilometers, Bulgaria ranks as the 16th largest country in Europe.
Bulgaria has a wealth of attractions for visitors, much more beautiful and diverse than you would ever expect, including wealth of historical monuments, long and beautiful sandy beaches, gorgeous mountain landscape with intriguing caves, waterfalls, striking rock formations, picturesque lakes and rivers, numerous different species of birds, plants and butterflies, ancient cultural and religious monuments, well-preserved medieval monasteries, vineyards and wineries, delicious traditional food, and welcoming and nice people. Many villages hidden in the Bulgarian mountains, pretty and colorful, keep alive the spirit and the culture of the Bulgarian Revival. Bulgaria is a vibrant Balkan country and therefore offers a wide variety of holidays as memorable cultural tours, beach holidays, ski holidays, golf, lakes and mountains holidays, horse-back riding and city breaks.
Bulgaria’s geography varies from vast lowlands in the north, highlands and elevated plains in the south, and the beautiful Black Sea coast in the east. Bulgaria features notable natural diversity, which consists of the Rila, Pirin and the Balkan Mountains landscape of the Alpine snow-capped peaks, the mild and sunny Black Sea coast, the fertile area of the typically continental Danube Plain /ancient Moesia/ occupying one-third of the country and the strong Mediterranean climatic influence in the valleys of Macedonia and in the lowlands in the southernmost parts of Thrace. Plains make about 30% of Bulgaria, while plateaus, mountains and hills account for 41%. The part of Southern Bulgaria that is not taken up by mountains carries the ancient name of Thrace (Northern Thrace, to be exact) and is home to wineries, orchards and fields of roses, sunflowers and tobacco. | http://lcc-panacomp.com/leisure/en/bulgaria |
A urinalysis is a common and frequently used diagnostic test that may be done in an inpatient or outpatient setting. A doctor usually orders a urinalysis as part of a routine health check-up or prior to certain medical procedures. If you or your doctor suspect that you may be experiencing symptoms of a chronic medical condition or disease, a urinalysis may be ordered to help identify any underlying issues.
Existing medical conditions and diseases may be monitored via several diagnostic tools that include urinalysis. Some medications that may impact the liver and kidneys after prolonged use may require frequent urinalysis in order to catch any issues as early as possible.
How is a Urinalysis Performed?
Typically, someone who needs to submit urine for testing will do so at a health care facility such as a lab or doctor’s office. The reason a person needs to undergo a urinalysis will determine if they need to fast or not before submitting a sample of their urine for review.
Persons who are able to collect the urine on their own will be provided the use of a bathroom, any clinical equipment they need and instructions on how to collect the urine safely and cleanly. In cases where a person is unable to collect their urine for testing, a health care professional may use a temporary catheter to collect the sample they require.
Once the sample has been collected, it will usually be examined by lab technicians in three distinct ways. A visual examination looks for any clear signs of infection, such as cloudiness or poor color or odor. A dipstick test will reveal any abnormalities with the chemical profile of a person’s urine, and a microscopic exam can help identify whether levels of any blood cells, bacteria, or yeast are within acceptable ranges of normal.
The results of a urinalysis are usually not available immediately and may require a few days to a week or more to be processed and reported to your physician. In emergency circumstances, such as during a hospital stay while undergoing treatment for an acute condition, results may be available within a few hours.
Medicare Coverage for Urinalysis
Diagnostic tests like a urinalysis are typically covered under Medicare Part B. In order to qualify for Medicare Part B coverage, a urinalysis must be deemed as medically necessary and ordered by an approved physician. A urinalysis for an inpatient recipient in the hospital or skilled nursing facility would fall under Medicare Part A coverage terms. Urine screenings for employment and other non-medical reasons would not be eligible for coverage under Medicare benefits.
With Medicare Part B coverage, most medically necessary diagnostic tests do not require copays or coinsurances. Part A benefits cover diagnostic tests for inpatient hospital stays. It’s important to note that the health care professionals and facility that perform a urinalysis must be Medicare-approved providers for coverage to apply.
Related articles: | https://www.medicare.org/articles/does-medicare-cover-urinalysis/ |
April 8, 2018
The Workshop “Man and Woman – A Sacred Union” – is a shared journey into our primordial nature, our essence. For 6 glorious days we will be discovering the inner space of each other and deeply dive together into recognition of our true nature.
This workshop is about how to go deeper into being Man and Woman; to recognize the nature of these qualities within ourselves and in others; to understand and to feel how different we are and that we are one. We will explore how to accept our female and male qualities and through acceptance and awareness we will find the way to build relationships based on love, freedom, and creativity.
This is an amazingly beautiful union of Man and Woman, where we learn about ourselves through body practices, connection with the Mother Earth, the Father Sky, and family leandge. For women – this is an amazing opportunity to accept your masculine nature; for men – this is an opportunity to recognize your sensual and emotional nature, and to accept your body and your connection with a physical mother and the Mother Earth.
You can participate individually or with a partner.
The workshop is taking place on a beautiful tropical island Bali, Indonesia, in retreat center located on the shore of the ocean, with a quiet beach and calm water. The price includes food and cozy cabin accommodation in the retreat center. | http://mayamandaladance.com/events/8-14-april-2018-bali-man-and-woman-a-sacred-union-with-maya-and-tyezan/ |
A team of physicists has managed to make homogenous cylindrical objects completely invisible in the microwave range without relying on metamaterial coatings. The method is based on a new understanding of electromagnetic wave scattering.
The scientists studied light scattering from a glass cylinder filled with water. In essence, such an experiment represents a two-dimensional analog of a classical problem of scattering from a homogeneous sphere (Mie scattering), the solution to which is known for almost a century. However, this classical problem contains unusual physics that manifests itself when materials with high values of refractive index are involved. In the study, the scientists used ordinary water whose refractive index can be regulated by changing temperature.
As it turned out, high refractive index is associated with two scattering mechanisms: resonant scattering, which is related to the localization of light inside the cylinder, and non-resonant, which is characterized by smooth dependence on the wave frequency. The interaction between these mechanisms is referred to as Fano resonances. The researchers discovered that at certain frequencies waves scattered via resonant and non-resonant mechanisms have opposite phases and are mutually destroyed, thus making the object invisible.
The work led to the first experimental observation of an invisible homogeneous object by means of scattering cancellation. Importantly, the developed technique made it possible to switch from visibility to invisibility regimes at the same frequency of 1.9 GHz by simply changing the temperature of the water in the cylinder from 90 °C to 50 °C.
“Our theoretical calculations were successfully tested in microwave experiments. What matters is that the invisibility idea we implemented in our work can be applied to other electromagnetic wave ranges, including to the visible range. Materials with corresponding refractive index are either long known or can be developed at will,” said Mikhail Rybin, first author of the paper and senior researcher at the Metamaterials Laboratory in ITMO University.
The discovery of invisibility phenomenon in a homogenous object and not an object covered with additional coating layers is also important from the engineering point of view. Because it is much easier to produce a homogeneous cylinder, the discovery could prompt further development of nanoantennas, wherein invisible structural elements could help reduce disturbances. For instance, invisible rods could be used as supports for a miniature antenna complex connecting two optical chips.
The subject of invisibility came into prominence with the development of metamaterials – artificially designed structures with optical properties that are not encountered elsewhere in nature. Metamaterials are capable of changing the direction of light in exotic ways, including making light curve around the cloaked object. Nevertheless, coating layers based on metamaterials are extremely hard to fabricate and are not compatible with many other invisibility ideas. The method developed by the group is based on a new understanding of scattering processes and leaves behind the existing ones in simplicity and cost-effectiveness. | https://scitechdaily.com/physicists-make-objects-invisible-without-metamaterial-cloaking/ |
Bauhaus gave a new dimension to what design can do for society. The Bauhaus school where the architect Ludwig Mies van der Rohe taught and served as the director since 1930, formed a new concept for the use of design.
The Bauhaus school first opened in Weimar in 1919. Its original mission was to create a place for mixing craftsmanship with the arts in the service of architecture. With time the mission changed and focused on uniting art with industrial techniques. As soon as Mies took over the directorship in 1930, it became mainly a school for architecture.
Sometimes the vagueness of a purpose can help a brand became more popular. Let a philosophical idea became your professional moto.
Bauhaus movement needed less than a decade to become the symbol of modern style & culture. Bauhaus redefined the idea of progressiveness across the world. It actually opened the doors of art and let society use its principals to reform the everyday life of world’s working classes.
The end of an era is not the end of the world. Changes are part of evolution, so learn to embrace them.
The given circumstances at these difficult years lead Mies and other Bauhaus masters to close the school in July 1933. They gathered together at the studio of the interior designer Lilly Reich in Berlin. They analyzed and discussed the financial and political situation of the school and came to the conclusion that it wasn’t possible to keep it open. The proposal was accepted with unanimous agreement, and the Bauhaus closed its doors.
This was the end of the Bauhaus school but not the end of Bauhaus. It triggered the birth of a design myth. Many architects and designers that began to flee Germany act as Bauhaus Ambassadors.
These well educated refugees pushed forward the principles of Bauhaus. As former teachers or students they had deep knowledge and the skills to implement Bauhaus into the society across Europe.
It was a historical alignment of good luck and need to adjust to new demands. Different countries and governments were trying to find ways to improve the city life. From building’s structure to floor designs and lifestyle changes to economy reformation.
Design can change the world. When it comes to professional decisions, trust the designers more than your personal taste of aesthetics.
Modernism had became the new hot trend of their time. People wanted to get rid of the old and bring in the new. Bauhaus movement found the perfect conditions to bloom. It was translated into different languages and went viral among a wide spread of geographical locations. It expand as an idea of transformation into a modern way of thinking & design and became a milestone in the history of mankind.
In that specific point, Aesthetics could transform the society inside its deep core. Design took the leading part of social transformation. And this overwhelmed the world. Goverments approved new buildings with the new Bauhaus design all over them. In that context, architecture & designers produced the foundations for the revival of the society by adopting a new way of living.
A great idea doesn’t need anyone’s approval to thrive. It’s above and beyond our personal power to control what happens after we create something.
As it usually happens, the first years, every designer had their strong opinion about what Bauhaus really was. Thousands of versions started to rise in different cities all over the world.
Naturally, the process was remarkably out of control. Over time, Bauhaus buildings and objects showed up in London, New York, Chicago, Tel Aviv., Germany, Russia, Greece, Italy, Spain etc.
The principal founder of Bauhaus, Walter Gropius, made his next step to Massachusetts as a professor at Harvard. The well know second director of Bauhaus, Hannes Meyer, continued his life to the Soviet Union. After the end of the WW, some remained in their new homelands and some returned back to the divided Germany.
Institute of Design at the Illinois Institute of Technology. Some years later, another Bauhaus institute was founded in the city of Ulm, West Germany, in 1950. It is known as the Ulm School of Design.
For historians, it is no surprise, that West Germany choosed the Bauhaus as their official symbol of democracy. In the following years, East Germany used it as a symbol of progress.
Bauhaus started as a idea of improvement among architectures and designers in 1919 and succeed to become a globally recognizable symbol of social & political transformation.
History has proved several times that less is more. The same principle apply into Web Design, Content Creation and Digital Marketing Strategy.
Simplicity is more complicated and sustainable than complexity. Less is more. Always. And stays forever.
I was born in Germany in 1973. Nowadays I live in Greece, but I keep visiting my birth country quite often. Last week I visited the remaining sites of Bauhaus, for the 100th anniversary of its opening.
The Bauhaus was one of the most influential modernist art schools of the 20th century. The foundation of its teachings were based to the relationship between art, society, and technology. It had a major impact both in Europe and in the United States long after its closure under Nazi pressure in 1933.
The Bauhaus was influenced by 19th and early-20th-century artistic directions such as the Arts and Crafts movement, as well as Art Nouveau and its many international incarnations, including the Jugendstil and Vienna Secession.
Gropius envisioned the Bauhaus—whose name means “house of building”—as a merger of craftsmanship, the “fine” arts, and modern technology. His iconic Bauhaus Building in Dessau was a forerunner of the influential “International Style,” but the impact of the Bauhaus’s ideas and practices reached far beyond architecture. Students of the Bauhaus received interdisciplinary instruction in carpentry, metal, pottery, stained glass, wall painting, weaving, graphics, and typography, learning to infuse even the simplest functional objects (like the ones seen in today’s Doodle) with the highest artistic aspirations.
Steering away from luxury and toward industrial mass production, the Bauhaus attracted a stellar faculty including painters Wassily Kandinsky and Paul Klee, photographer and sculptor László Moholy-Nagy, graphic designer Herbert Bayer, industrial designer Marianne Brandt, and Marcel Breuer, whose Model B3 tubular chair changed furniture design forever. | https://ideadeco.co/2019/04/13/bauhaus-movement-five-lessons-for-todays-content-creators/ |
The Antikythera Mechanism is one of the mysteries of ancient Greece. Was the ancient Greek mechanism a navigation device, analog computer, or something else?
Ancient Greek Antikythera Mechanism
Does an analog computer dating back over 2000 years sound like fantasy? It might do, if not for the fact that one was discovered in a shipwreck off the coast of Greece!
The Antikythera Mechanism is one of the greatest mysteries of Ancient Greece and mankind's history.
Mysteries of Ancient Greece
When I was in my early teens, I became interested in ancient civilizations. They always seemed somewhat mysterious to me.
This sense of mystery was added to by reading Erich Von Daniken books such as Chariots of the Gods.
I never agreed with his ancient astronaut theories, but I did come to realise that ancient civilisations were far more advanced than we give them credit for.One mysterious object that I remember reading about in his books, was the Antikythera Mechanism. It was over 2000 years old, and seemed to be technologically far ahead of its time.
Imagine my delight then, when I discovered that it had its own exhibition room at the National Archaeological Museum of Athens. Now, I could see it for myself!
The Antikythera Mechanism
I know what you are thinking. “This doesn't look much”, right? Oh, how wrong you are though!
You have just made the same mistake that scholars, archaeologists, and museum cataloguers did for two years after its discovery in 1900.
It was only in 1902 that someone finally noticed the inscriptions and gear wheel. This is hardly surprising really, because the other objects found around the same sunken ship were magnificent.
Huge bronze statues and glass vessels were recovered by divers, and so some objects were overlooked. The Antikythera Mechanism was one of them.
What does the Antikythera Mechanism do?
After years of research, it was finally decided that the Antikythera Mechanism was designed to predict astronomical positions and eclipses, as well as the Olympiads, which were the cycles of the Olympic Games held in antiquity.
It did this by a series of gears and levers. In some circles, this was known as an astrolabe. To others though, this effectively made it the worlds first analog computer.
Two things could be concluded by this – Either the Antikythera Mechanism was a one off design and build. Or, it was one in a series of mechanical devices which had been developed over years.
The great ancient Greek scientist Archimedes has been linked with its design and build, although there is no actual proof to support this.
Regardless of who built it, it was certainly an example of how advanced society had become during the Hellenistic period. The skills and knowledge required to build such a device would not surface again until after the 14th century.
Where is the Antikythera Mechanism now?
This is one of the most astonishing finds in archaeology, because it rewrites history. Not only that, but it also reveals a level of sophistication, knowledge, and technology that was unknown before.
If you are visiting Athens in Greece, I would highly recommend visiting the National Archaeological Museum of Athens so that you can see it for yourself. In the mean time, I have posted an interesting documentary below.
Travel Guides To Greece
Would you like to find out more about things to see and do in Athens and Greece? These Greek blogs might help: | https://www.davestravelpages.com/the-antikythera-mechanism-mysteries-of-ancient-greece/ |
Chiss are blue-skinned humanoids from the planet Csilla in the Unknown Regions.
As remote and secretive as the distant star system from which they emerged, the Chiss species remains a mystery to most of the galaxy. Completely removed from the Republic and the Empire, these blue-skinned humanoids evolved from an advanced civilization known as the Chiss Ascendancy in the Unknown Regions of space. Despite constant political power struggles among the ruling class, the Ascendancy maintained strict controls over its dominion, and the civilization prospered. This is how the Chiss developed socially and technologically in isolation for thousands of years, until they were discovered by the Sith Empire.
During the later period of the Empire's exile, the Sith came into contact with the Chiss. In every previous instance where the Empire had encountered an alien civilization with enough technology and resources to defend itself, the Empire demanded surrender and capitulation to the rule of the Emperor. Each civilization refused and the Sith conquered their worlds and killed or enslaved the inhabitants. The power struggles of the Ascendancy are rarely solved with force of arms, and the Chiss ruling class surprised the Empire by considering the offer on its merits and asking for a summit. The Empire's military leadership, confused, agreed. The Chiss' behaviour was unlike that of any previous civilization confronted with the Sith, and the event remains unique today.
Behind closed doors, the best Chiss negotiators met with a selection of important Imperial diplomats, including the unusual presence of the commander of the secretive Imperial Guard. Nothing has ever been publicly revealed about that meeting except for the outcome, the discussions leading to which are now contemplated by diplomats and historians the galaxy over. The Chiss would become the first official allies of the emperor. Their armies, resources and tax revenues would be offered to the Empire. In return, the Empire would allow the Ascendancy to govern and administer its own planets, and never set foot on the Chiss home-world of Csilla without permission. Not one political representative, not one noble tourist, not one Sith.
In the years that followed, the Chiss assisted the Sith in the invasion of Republic space and earned the Empire's respect and trust as military allies. While in Sith controlled space, the Chiss submit to Imperial authority without question and a handful of Chiss have even integrated themselves into Imperial society. Nonetheless, the Chiss Ascendancy maintains its own forces, separate from the Imperial military, and most members of the species still retain their characteristically private ways, even when working closely with their heavy-handed Imperial allies. To the Republic, the Chiss continue to be a complete mystery and the species' very existence is unknown except in high-level political and military circles.
Social Ability: Salute - Prompts nearby allies to stand at attention. | https://www.ign.com/wikis/star-wars-the-old-republic/Chiss |
Clinical research on the incision line selection of video-assisted thoracoscopic wedge resection of the lung.
To compare the clinical efficacy of video-assisted thoracoscopic direct lung wedge resection (banana peel method) with that of the opposite resection line (traditional method). Review and analysis of 83 cases of video-assisted thoracoscopic wedge resections of lung operations from February 2007 to September 2011. All of the patients were divided into two groups, as follows: Group A: wedge resection of the lung by the opposite resection line (traditional method), 41 cases; Group B: direct lung wedge resection (banana peel method), 42 cases. Both of the groups received video-assisted thoracic surgery. The postoperative follow-up period was 1-6 months, with an average of 3.6 months. The operating conditions (including operation time, transoperative bleeding volume, number of transoperative sutures added, postoperative time to extubation, surgery cost, number of suturing instruments used for incising with the endoscope and the cost of hospitalisation), atelectasis conditions 1 month after the operation and the decreasing lung function conditions were compared between groups. Group B's operative time was (62 ± 10) min, significantly less than Group A's (81 ± 16) min (P < 0.05). The amount of bleeding in Group B was (52 ± 17) ml, which was also significantly less than that of Group A, at (74 ± 21) ml (P < 0.05). Compared to Group A, Group B had significantly (P < 0.05) fewer manual sutures and shorter postoperative extubation times. The cost of surgery and number of endoscopic staplers used during the operation in Group B were significantly larger than in Group A; however, the total hospital costs did not differ between the two groups (P > 0.05). Neither group had any cases of atelectasis based on chest X-ray films taken 1 month after the operation, and no difference was found in the groups' decreased lung functions. The video-assisted thoracoscopic direct lung wedge resection (banana peel method) can shorten the operative time, lessen the surgical trauma, reduce the number of additional manual sutures required, and make for an overall more convenient operation, compared to wedge resection of lung by opposite resection line (traditional method). Although operation costs have increased, the total hospital costs have not. Thus, the better choice for video-assisted thoracoscopic lung wedge resections involves the use of direct lung wedge resection.
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My first encounter with learning styles was some thirty years ago in a training session held for adult educators by the Chamber of Commerce in Austria. The discovery that people learn differently was eye-opening to me as it helped to explain the successes and failures I had had myself as a language learner. After that first introduction, I became very interested in the topic and began to study different styles, experiment in language classes with ideas and look into ways to help students who had questions about learning a language.
Much to my surprise, several years ago I began reading newspaper articles and posts on social media with titles such as ‘Learning styles don’t work’ or ‘Debunking the myth of learning styles’. I have attempted to follow the arguments and the claims that styles either don’t exist or it isn’t necessary to take them into account. What I would like to do in this article is to address these points and explain my point of view regarding the differences I have observed over the years of teaching and working as a teacher trainer.
It is unclear to me what is meant by the comment ‘learning styles don’t work’. In my opinion, they are not supposed to ‘work’, they are simply a method we have at hand for learning more about individual learners in order to help them achieve their goals. I agree wholeheartedly that adapting instruction to fit each individual style is not only very difficult to do but most likely not very helpful in the classroom. Instead, knowing a variety of methods and approaches that we can use gives learners new possibilities to experiment and develop new strategies to help them be successful language learners.
First of all, I think it is necessary to pinpoint which styles may actually come into question for teachers. Over the years a number of styles have been defined which adds to the confusion of what to do in the classroom. Based on a combination of classroom observation, two small-scale research projects and discussions with a wide range of educators, I have limited my use of ‘styles’ to the three areas mentioned by Andrew Cohen as being useful to understanding the process of language learning. These are: sensory/perceptual, cognitive and personality-related preferences. For me this translates to three models: visual, auditory and kinaesthetic perception based on research by Walter Barbe and Raymond Swassing (1979); global and analytic cognitive processing as defined by Herman Witkin (1977), and a model called ‘Mind Organisation’ created by April Bowie (1997) which determines preferred behaviour in learners.
The main point of this article, however, deals with misconceptions about the use of styles. It is important that they are not seen as limitations; in fact, once we are aware of our own strengths it is easier to try out new ideas and experiment with new ideas and with learning in general. In some cases, learners will do this on their own, in others the teacher can challenge learners to take chances and stretch out of their preferred styles.
Styles are also not ‘right or wrong’; some may just be more conducive than others for learning a particular subject. It is also necessary to differentiate between style and competence. Not everything is easy or enjoyable to learn but when the motivation is there, learners find ways to succeed in spite of their difficulties. It should also be kept in mind that the goal of working with styles is not to pigeon-hole learners but simply to be aware of the differences and use a mix of methods to reach as many students as possible. In cases where a learner has not understood a concept, explaining it in a different way may help him or her to grasp the concept. When we first harmonise with learners and then challenge them, we can help them to stretch out of their preferred modes and become autonomous and independent learners. As Guild and Garger say ‘it is possible to strive for uniform outcomes but to intentionally diversify the means for achieving them’.
For those who have asked for ‘evidence of styles’ I would argue that eliminating the concept of styles from our teaching does not take the learners’ own experience into account. When a learner has determined what he or she needs in order to be successful, this should be respected. It may be the case that when we ask our learners what helps them to learn, we will gain valuable insight into the types of activities we plan for the classroom. Teaching and learning is a two-way street and each of us is a vital part of the journey. Remaining flexible and embracing the idea that one-size does not fit all can only enhance the experience of learning and lead us to a wide variety of methods and approaches which will be beneficial to both our students and to us as educators and life-long learners. | https://www.hltmag.co.uk/apr19/learning-styles |
How to Write Communication Essay
Communication essays are a hard nut to crack for many students who do not know the basics of writing this type of paper. Previously, we discussed the basic elements of justice essay and its types. Before discussing the key points of writing communication essays, there is a need to provide a definition of this type of academic writing. Essay on communication is focused on the process of interaction between people and their environment. According to Wikipedia, communication studies refer to an educational discipline that is concentrated on the process of human communication and can be of different types, which are:
- Verbal communication that involves listening to the conversation partner in order to understand the meaning of the shared information.
- Written communication, during which the shared message is read.
- Non-verbal communication that involves observing a person to understand his/her message delivered with the help of non-verbal means of communication.
Essays on communication can be of different types, each of which will be observed in detail in the current essay. Thus, there are such types as nonverbal communication essay, intercultural communication essay and interpersonal communication essay. In order to understand how to write each of the above-mentioned types of communication essays, one needs to know their definitions and basic elements, as well as the key principles of writing these particular types of essays. All this will be discussed as follows.
- Non verbal communication essay is focused on the non verbal means of delivering a message to the conversation partner. According to Wikipedia, nonverbal communication stands for a kind of communication that implies sharing messages through wordless clues. This includes four basic elements, namely the use of visual clues, body language, distance and physical appearance, voice and touch. Written communication is comprised of certain elements of nonverbal communication, namely the style of handwriting that differs from person to person. It should be noted that only a small portion of brain processes verbal information in the course of communication process. The rest resides with nonverbal communication. That is why it is of great importance to know the basic features of nonverbal communication in order to interpret the message delivered by the conversation partner in a correct way. As for nonverbal communication essay, basically, it deals with various nonverbal methods of communication including voice, gestures, eye contact and many others. Understanding of every means of nonverbal communication is important for writing the essay about communication properly. You need to be attentive to the body language of your conversation partner in order to interpret his/her message correctly and understand what he/she wants to say. If you learn to understand nonverbal means of communication, the task of writing a communication essay will become easier.
- As for interpersonal communication, it is also a field of study that investigates the nature of the information exchange between two or more people. According to Wikipedia, successful interpersonal communication means the process of communication between the sender and the receiver, in which both parties understand the message being delivered. Interpersonal communication essay is not easy to write if you lack certain skills and knowledge on this field of study. However, there are certain tips that might help you write an essay on interpersonal communication. First, you need to understand the topic of your research and find required information for the study looking through all the available materials on the discussed topic. Second, you should choose only trustworthy resources for writing an essay on interpersonal communication, as a considerable part of the materials available on the web is not reliable enough to compose a decently written paper. Third, you should consult your professor or supervisor in case you have any questions about the topic of your essay before proceeding to writing the paper. Finally, you need to investigate the given topic to full extent to compose a well-written paper on interpersonal communication. This field of study is a tricky one, so you need to learn the basics first and then expand your knowledge on the given topic. If you follow all the above requirements, you will be sure that you will get the highest grade for your paper without any additional effort. If you want to learn more about interpersonal communication, check our website.
- Intercultural communication essay deals with sharing of information by various social groups and people with different cultural background. In order to write this type of essay, you should understand the peculiarities of different cultures. It is widely known that in today’s globalized world, understanding of other cultures is important for successful intercultural communication with members of different cultural groups. It is easy to be misinterpreted if you speak to a representative of another culture because people from other countries use a different body language and different means of non-verbal communication. Verbal communication obviously differs from culture to culture, and you need to be careful when speaking a foreign language with a representative of another culture. According to Wikipedia, knowledge about intercultural communication should include understanding of how people from other cultures perceive the world around them and what means of communication they use during conversation. In order to write a good intercultural communication essay, you need to understand the key peculiarities of different cultures and distinguish various verbal and nonverbal means of communication used by different social groups. This will ensure that your paper will deserve the highest mark.
Finally, it needs to be noted that essays on communication can be tricky if you do not know much about the verbal and nonverbal means of message delivery, communicative means used by different cultures and peculiarities of interpersonal communication. The basic requirement for writing a communication essay is to understand the essence of various kinds of communication as discussed above. This will ensure that your essay is written well and deserves the highest grade. Understanding the basics is important for writing any type of essay, especially the essay on communication, so don’t hesitate to expand your knowledge about various aspects of human communication to deliver the best-written paper to your professor. Otherwise, you can order communication essay on our website and we will make sure your essay is written to the best of our writers’ abilities. | https://bigessaywriter.com/blog/how-to-write-communication-essay |
Establish a new strategy for an effective end-to-end launch campaign through early conversations with key stakeholders.
Bringing a new product to market is complex, and launching in a new market is even more so. Within the post pandemic environment, there is a lot we can do to virtually to ensure effective drug establishment and distribution, from out-licensing, partnerships, virtual ad boards to engaging with payers and customers. Hence, opportunities to execute an effective product launch is within your reach.
To secure a successful commercialization strategy, we must educate, motivate and communicate with all stakeholders from across the launch journey, to maximize launch impact. Whether you're launching into familiar or unfamiliar markets, engaging key decision makers must happen as early as possible, in order to navigate the regulatory and market access landscape. From pre to post product commercialization, we must build relationships, drive new collaborations and leverage launch synergies to streamline product reviews and ensure appropriate uptake.
In this session the panel we will explore the key decisions that pharmaceutical companies should be considering early in the product journey, to ensure a successful end-to-end launch campaign.
Business-critical insights from Merck, CSL Behring, Takeda and Innomar Strategies include: | https://www.reutersevents.com/pharma/access-and-evidence/webinar/webinar-your-24-month-blueprint-launch-success-02062022 |
Madagascar is one of the most biologically diverse places on the planet, the result of 160 million years of isolation from the African mainland. More than 80% of its species are not found anywhere else on Earth. However, this highly diverse flora and fauna is threatened by habitat loss and fragmentation, and the island has been classified as one of the world’s highest conservation priorities.
Drawing on insights from geography, anthropology, sustainable development, political science and ecology, this book provides a comprehensive assessment of the status of conservation and environmental management in Madagascar. It describes how conservation organisations have been experimenting with new forms of protected areas, community-based resource management, ecotourism, and payments for ecosystem services. But the country must also deal with pressing human needs. The problems of poverty, development, environmental justice, natural resource use and biodiversity conservation are shown to be interlinked in complex ways. Authors address key questions, such as who are the winners and losers in attempts to conserve biodiversity? And what are the implications of new forms of conservation for rural livelihoods and environmental justice?
"The relations between society and nature in Madagascar are complex and often misunderstood. This book offers new light on this subject by exploring the social, political and economic dimensions of conservation and development challenges." – W.M. Adams, Moran Professor of Conservation and Development, University of Cambridge, UK
"The challenges laid down by Scales are a must read for those seeking to understand the current plight of the island and anyone with an interest in the environmental future of Madagascar… It is a timely text that should be required reading for anyone seeking to acquaint themselves with the environmental problems of Madagascar. The work offers very good socio-economic and political background on the island’s conservation history, and, with an eye to the future, the concluding chapter offers suggested research and policy priorities that need to be addressed." - Clive Nuttman in Conservation Biology (2015)
"It tries to look at both the misinformation that has underlain much of the received wisdom on conservation in Madagascar, while also examining in considerable detail the politics of conservation and environmental management… In summary, a useful book." - Bulletin of the British Ecological Society
"The volume is highly interdisciplinary and international, and its overarching concern is the sometimes cooperative, sometimes antagonistic relationship between environmental conservation and human development. Summing Up: Recommended. Graduate students and researchers/faculty." – CHOICE, W. Arens, Stony Brook University
1. Introduction: Conservation at the Crossroads: Biological Diversity, Environmental Change and Natural Resource Use in Madagascar
Ivan R. Scales
Part 1: Madagascar’s Biological Diversity: From Deep Time to the Arrival of Humans
2. Explaining Madagascar’s Biodiversity
Jörg U. Ganzhorn, Lucienne Wilmé and Jean-Luc Mercier
3. Early Human Settlers and their Impact on Madagascar’s Landscapes
Robert E. Dewar
Part 2: Paradise Lost? The Myths, Narratives and Received Wisdoms at the Heart of Conservation Research and Policy
4. Deforestation in Madagascar: Debates over the Island’s Forest Cover and Challenges of Measuring Forest Change
William J. McConnell and Christian A. Kull
5. The Drivers of Deforestation and the Complexity of Land Use in Madagascar
Ivan R. Scales
Part 3: The Politics of Biodiversity Conservation and Environmental Management
6. A Brief History of the State and the Politics of Natural Resource use in Madagascar
Ivan R. Scales
7. The Roots, Persistence, and Character of Madagascar’s Conservation Boom
Christian A. Kull
8. The Transfer of Natural Resource Management Rights to Local Communities
Jacques Pollini, Neal Hockley, Frank Muttenzer and Bruno Ramamonjisoa
9. Conservation Politics in Madagascar: The Expansion of Protected Areas
Catherine Corson
10. The Durban Vision in practice: Experiences in the Participatory Governance of Madagascar’s New Protected Areas
Malika Virah-Sawmy, Charlie J. Gardner and Nanie A. Ratsifandrihamanana
Part 4: Making Conservation Pay? Incentive-Based Conservation, the Commodification of Madagascar’s nature and Conflicting Views of Landscape and Nature
11. Tourism, Conservation and Development in Madagascar: Moving Beyond Panaceas? | https://www.routledge.com/Conservation-and-Environmental-Management-in-Madagascar/Scales/p/book/9780415528764 |
FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION
SUMMARY OF THE INVENTION
The present invention relates generally to the field of database methods and systems. More particularly, the present invention relates, in one aspect, to methods and systems for analyzing and mining information stored in database systems. Still more particularly, aspects of the present invention relate to identifying and extracting information exhibiting inter-relationships and temporal cycles.
Recent advances in data collection and storage technology have made it possible for many companies to keep large amounts of data relating to their business online. At the same time, low cost computing power has also made enhanced automatic analysis of these data feasible. This activity is commonly referred to as data mining.
One major application domain of data mining is in the analysis of transactional data. In this application database system records include information about user transactions, where each transaction is a collection of items. In this setting, association rules capture inter-relationships between various items. An association rule captures the notion of a set of items occurring together in transactions. For example, in a database maintained by a supermarket, an association rule might be of the form “beer→chips (3%, 87%),” which means that 3% of all database transactions contain the items beer and chips, and 87% of the transactions that have the item “beer” also have the item “chips” in them. The two percentage parameters above are commonly referred to as “support” and “confidence,” respectively. Typically, the data mining process is controlled by a user who sets minimum thresholds for the support and confidence parameters. The user might also impose other restrictions, such as restricting the search space of items, in order to guide the data mining process.
Proc.
ACM SIGMOD Intl. Conf. on Management of Data
Following the early work in Agrawal, R., T. Imielinski and A. Swami “Mining Association Rules between Sets of Items in Large Databases,” 1993 , pp. 207-216, Wash., D.C., May 1993, association rules have been extensively studied. (The last-cited paper will be referred to in the sequel as “Agrawal, et al 93.”) However, this work treats data as one large segment, with no attention paid to segmenting data over different time intervals. For example, returning to our previous example, it may be the case that beer and chips are sold together primarily between 6 PM and, 9 PM. Therefore, if we segment the data over the intervals 7 AM-6 PM and 6 PM-9 PM, we may find that the support for the beer and chips rule jumps to 50%.
Prior data mining systems and methods have failed to provide for identifying, analyzing and reporting time-dependent associated data in an efficient, readily usable manner.
Limitations of the prior art are overcome and a technical advance is made in accordance with the present invention described in illustrative embodiments herein.
In one aspect, the present invention provides systems and methods for discovering regularities in the behavior of association rules over time. These techniques enable marketers and others to better identify trends in sales and other contexts, and to allow better forecasting of future events, such as user demand for products, services or other resources.
Typically, transactional data to be analyzed are time-stamped and user-divided into disjoint segments corresponding to respective time intervals. In a common arrangement, users opt for “natural” segmentation of data based on months, weeks, days, etc. In any event, users are usually best qualified to make this decision based on their understanding of the underlying data.
In accordance with another aspect of the present invention, we refer to an association rule as cyclic if the rule has the minimum confidence and support at regular time intervals. Such a rule need not hold for the entire transactional database, but rather only for transactional data in a particular periodic time interval. That is, each cyclic rule must have the user specified minimum support and confidence over a specific periodic time interval. The user typically specifies upper and lower bounds for the periods of such time intervals.
We consider mining cyclic association rules as generating all cycles of association rules. Given a large database comprising transactional information, where each transaction consists of a transaction-id, a set of items and a time-stamp, we provide efficient algorithms to discover such cyclic association rules.
In studying the interaction between cycles and association rule mining, we identify techniques for cycle pruning, cycle skipping and cycle elimination that allow us to significantly reduce the amount of wasted work typically expended during data mining processes.
While an extension of existing association rule mining techniques (treating association rules and cycles independently) can be pursued for some applications, preferred embodiments of the present invention generates cyclic association rules using a two-phase technique. In a first phase, cyclic large itemsets are discovered and advantageously reduced using cycle-pruning, cycle-skipping and cycle-elimination techniques. In a second phase cyclic rules are discovered by sequentially processing results from phase one for each user-specified time interval.
Further aspects of inventive embodiments and the effectiveness of described techniques are demonstrated in disclosed examples.
BRIEF DESCRIPTION OF THE DRAWING
The above-summarized description of illustrative embodiments of the present invention will be more fully understood upon a consideration of the following detailed description and the attached drawing, wherein:
FIG. 1
is an overall view of an illustrative system for carrying out data mining operations in accordance with illustrative embodiments of the present invention.
FIG. 2
shows one illustrative format for a transaction data record.
FIG. 3
shows an illustrative embodiment of a sequential method (algorithm) in accordance with one aspect of the present invention.
FIG. 4
is a flowchart of an illustrative method for determining cycles for detected association rules.
FIG. 5
shows steps illustratively performed in eliminating non-large cycles.
FIG. 6
shows an interleaved algorithm in accordance with an illustrative alternative embodiment of the present invention.
DETAILED DESCRIPTION
EXAMPLE 1
EXAMPLE 2
EXAMPLE 3
EXAMPLE 4
APPENDIX 1
Interleaved Algorithm for Cyclic Large Itemset Detection
APPENDIX 2
Procedure Used for Cyclic Rule Generation
Overview of Typical Cyclic Data Mining Processes
Based on the examples of prior analyses of the type cited above, we observe that although an association rule may have the user specified minimum confidence and support within the entire time spectrum, analysis of the data in finer time granularity may reveal that the association rule exists only in certain time intervals, and does not occur in the remaining time intervals. In this section, we further illustrate cyclic data patterns in data mining rules and present a simple example of such cyclic patterns arising from transaction data records. While this and other examples may provide a context, such as supermarket sales records, it should be understood that such examples are merely typical, and in no way limit the applicability of the present invention and its many embodiments.
Observation of many association rules over monthly data may disclose seasonal variation where peaks occur at approximately the same month in each year. Association rules can also display regular hourly, daily, weekly, etc., variation that has the appearance of cycles. It is also possible that an association rule does not have the user specified minimum confidence and/or support over the entire time spectrum, but its confidence and support are above the minimum threshold within certain time intervals. We have found that these time intervals sometimes display a periodicity, and that discovering association rules and their periodicities may reveal interesting information that can be used for real world prediction and decision making.
Using another supermarket example to which the present inventive techniques may be applied, we analyze sales data over several months. More specifically, assume that we are interested in selling patterns for the items coffee and doughnuts. If we were to look at the overall support for coffee and doughnuts occurring together in transactions, we might discover that the two items do not have enough support (i.e., these items do not meet the minimum threshold for support specified by the user). However, if we look into hourly sales figures, we might discover that coffee and doughnuts have a strong tendency to occur together with high support during the time interval 7 AM-9 AM. That is, “coffee→doughnuts” during the interval 7 AM-9 AM every day. Further analysis might also reveal a larger weekly tendency, wherein coffee and doughnut sales dip during weekends.
Illustrative System Overview
FIG. 1
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The present inventive systems and methods can be embodied in a number of forms. While special purpose digital logic may be used to implement the current inventive techniques, it usually proves more convenient to use one or more programmed general purpose computers to realize the advantages of embodiments of the present invention. shows one such illustrative embodiment of the present invention. There, a user workstation or personal computer is shown connected to a server or database computer . Database computer (server) comprises a database management system , which, in turn, comprises the operating system and commercially available database management system software, such as database manager software available from Oracle or IBM Corporation. Other particular database management software may, of course, be used, as may suit user requirements or preferences and particular characteristics of data records stored in transaction database . Data records in database comprise the transaction or other records to be processed to determine the existence of any cyclic association rules.
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In applying the processing to be described in more detail below in connection with particular embodiments of the present invention, it proves convenient to frame user requests and requirements using keyboard or other input devices in terms recognizable to a software module such as database mining kernel in FIG. . Kernel may be any of a variety of software modules which provide, for example, a toolkit of algorithms and processing techniques that allow users to analyze data in database . Such kernels are available from IBM Corporation, Oracle and others and allow operations including deviation detection, classification and predictive modeling, association, sequential pattern discovery, and database segmentation. In application development, these kernels typically provide a graphical, icon-based environment for developers to use and combine transformers (executable objects) to perform required functions. One such kernel available from IBM Corp. runs on AIX, OS/400, and OS/390 platforms, and it supports clients on AIX, Windows, and OS/2. The functionality of kernel may also be provided by appropriate specially developed queries and database management instructions provided by a user to the database management system.
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The combination of server operating system, database management system (collectively database manangement system ) and illustrative database mining kernel are accessed by user terminal through local wire or wireless connections, or over a local area network, or over a more extensive network—such as a campus network, wide area network or the Internet. User-defined selection and other criteria defined in a user-developed application are typically imposed through database mining kernel and the database management system on the data records in transaction database . Records or analyses of record sets are thereby non-destructively read or extracted from transaction database, and these results are stored, at least temporarily, in illustrative results database or results file . As is known in the art, data structuring and storage can greatly influence operating speed. Accordingly, some applications of the present inventive techniques will seek to store intermediate and final results of processing in main memory of server rather than in secondary storage such as disk or tape memory—when available system capacity makes this possible.
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In appropriate cases, user applications can be developed and run at user terminal for interaction with database mining kernel on a server such as that shown in FIG. . In other cases, such applications can be run entirely at the user location . That is, the kernel functionality, database manager and database can all be operative at the user location . In these latter cases, user terminal will typically include workstation functionality and sufficient storage for substantial data sets. In yet other cases, a workstation having kernal functionality will interact with separate database systems to perform the mining of such separate databases. This latter arrangement avoids the need to store all needed data sets at the workstation , and permits different users at respective workstations (or personal computers) to access the same database for mining purposes. While application of the present invention presented herein may illustrate or suggest the use of one or more of such configurations, it should be understood that inventive method and system solutions in accordance with the present inventive teachings can be embodied in any of the above-mentioned configurations—or combinations of such configurations.
FIG. 2
FIG. 2
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k
shows an example of a transaction data record having a timestamp field and a plurality of item fields, ITEM(K), for K=1, . . . , K(MAX). In general, an ITEM(K) for some K may correspond to any item, e.g., coffee or doughnuts in the above example. Other formats for transaction records may be used, or the format of may take a particular detailed arrangement for some applications. In Agrawal, et al 93, the authors propose a binary transaction vector with t[k]=1 if customer t bought the item I, and t[k]=0 otherwise that proves useful in representing transactions. In many cases standard flat files of data transactions will prove appropiate. Transaction records may, of course, include other transaction data, such as customer or seller identification (department, store location, etc.).
Formal Problem Definition
It proves useful to now introduce definitions, notation and contexts to help in understanding the use of illustrative embodiments and applications of the present invention.
Thus, given a set of items and a set of transactions, where each transaction consists of a subset of the set of items, the problem of discovering association rules is defined as finding relationships between the occurrences of items within transactions. An association rule of the form X→Y is a relationship between the two disjoint itemsets X and Y (an itemset is a set of items). An association rule is described in terms of support and confidence.
min
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The support of an itemset X is the fraction of transactions that contain the itemset. An itemset is called large (or, sometimes,frequent), if its supports exceeds a given threshold sup. Likewise, if support for the set of transactions containing both X and Y, i.e., X∪Y, exceeds a chosen sup, then X∪Y is large.
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The confidence of a rule X→Y is the fraction of transactions containing X that also contain Y. The association rule X→Y holds if X∪Y is large and the confidence of the rule exceeds a given threshold con.
FIG. 2
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To deal with cyclic association rules, we enhance the transaction model by a time attribute that describes the time when the transaction was executed. (This time attribute is represented in by the field labeled TIME.) In this description, we assume that a unit of time is given (e.g., by the user, or by a default mechanism). For simplicity of presentation, other treatments of time, such as multiple units of time and/or a time hierarchy, will not be expressly treated in this description, but those skilled in the art will make adjustments within the spirit of the present teachings to incorporate uses of such altrnative treatments of time. We denote the itime unit, i≧0, by t. That is, tcorresponds to the time interval [i·t, (i+1)·t), where t is the unit of time. We denote the set of transactions executed in tby D[i]. It proves convenient to refer to D[i] specifically as “time segment i” or generically as a “time segment.” We define the problem of discovering cyclic association rules as finding cyclic relationships between the presence of items within transactions.
i
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The support of an itemset X in D[i] is the fraction of transactions in D[i] that contain the itemset X. Likewise, support of an itemset X∪Y in D[i] is the fraction of transactions in D[i] that contain the itemset X∪Y. The confidence of a rule X→Y in D[i] is the fraction of transactions in D[i] containing X that also contain Y. An association rule X→Y holds in time unit t, if the support of X∪Y in D[i] exceeds sup, and the confidence of X→Y exceeds con.
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A cycle c is a tuple (l, o) consisting of a length l (in multiples of the time unit) and an offset o (the first time unit in which the cycle occurs), 0≦o<l. We say that an association rule has a cycle c=(l, o) if the association rule holds in every ltime unit starting with time unit t. For example, if the unit of time is an hour and “coffee→doughnuts” holds during the interval 7 AM-8 AM every day (i.e., every 24 hours), then “coffee→doughnuts” has a cycle (24, 7). We denote the minimum and maximum cycle lengths of interest by land l, respectively. We refer to an association rule that has a cycle as cyclic. An association rule may have multiple cycles. For example, if the unit of time is an hour and “coffee→doughnuts” holds during the interval 7 AM-8 AM and 4 PM-5 PM every day (i.e., every 24 hours), then “coffee→doughnuts” has two cycles: c=(24, 7) and c=(24, 16).
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We say that a cycle (l, o) is a multiple of another cycle (l, o) if ldivides land (o=omod l) holds. By definition, once a cycle exists, all of its multiples with length less than or equal to lwill exist. Therefore, a primary interest is to discover “large” cycles, where a large cycle is the one that is not a multiple of any other cycle. A time unit tis said to be “part of a cycle” c=(l, o) or “participate in a cycle” c if o=i mod l holds.
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An association rule can be represented as a binary sequence where the ones correspond to the time units in which the rule holds and the zeros correspond to the time units in which the rule does not have the minimum confidence or support. For instance, if the binary sequence 001100010101 represents the association rule X→Y, then X→Y holds in D[2], D[3], D[7], D[9], and D[11]. In this sequence, (4,3) is a cycle since the corresponding rule holds within every fourth time unit stating from time unit t. A cycle can also be represented by a binary sequence. For example, cycle (4,3) can also be represented as 0001.
Similar to association rules, itemsets can also be represented as binary sequences where ones correspond to time units in which the corresponding itemset is large and zeros correspond to time units in which the corresponding itemset does not have the minimum support. Also, an itemset is said to be cyclic if the itemset is large at regular intervals (i.e., the sequence representing the itemset is cyclic).
Discovering Cyclic Association Rules
Though useful in many respects, existing algorithms for discovering association rules cannot be applied for discovering cyclic association rules. In order to use existing algorithms for detecting cyclic association rules, one might consider extending the set of items with time attributes, and generate rules. For example, one such rule could be (day=monday)∪X→Y. This approach segments the database such that all transactions that have the same time attribute value are within the same segment. For example, if the time attribute is day, then all the transactions that occurred on Mondays will be within one segment. In this case, the support of the rule (day=monday)∪X→Y is the ratio of the fraction of all transactions that occurred on Mondays and contain X and Y to all transactions. Similarly, the confidence of this rule is the ratio of (i) the fraction of all transactions that occurred on Mondays and contain X and Y to (ii) the fraction of all transactions that occurred on Mondays and contain X. However, there are a number of reasons why such an approach will not solve our problem, as we show below.
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First, it is possible that this approach will detect non-existing cycles. For example, this approach may detect that every Monday X→Y holds, although X→Y holds only every second Monday, or only on some Mondays but not on all. This may occur, for example, when the support of (day=monday)∪X∪Y exceeds sup, but the ratio of the fraction of all transactions that occurred on some Mondays that contain both X and Y to all transactions is below sup. That is, the ratio of the fraction of all transactions that occurred on the remaining Mondays that contain both X and Y to all transactions is high enough to compensate for the other Mondays. In this case, this approach assumes that the support for (day=monday)∪X∪Y exceeds the minimum support threshold, although, in fact, the support of only (day=only−some−mondays)∪X∪Y is above the minimum threshold. Therefore, a non-existing cycle every Monday can be mistakenly identified. Another problem with this approach is that it cannot detect cycles of abitrary lengths. For example, it cannot detect an association rule that holds every 10 days.
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One may also consider the following approach to apply the existing algorithms for detecting cyclic association rules. Each transaction in a time unit tis extended with all possible cycles in which time unit tcan participate (there are lsuch cycles, where lis the maximum cycle length of interest). Such an approach will generate rules in the form of (cycle=(l, o))∪X→Y. Thus, each possible cycle c=(l, o) defines a segment that consists of all the transactions that occurred in each time unit tfor which (o=i mod l) holds. In this case, the support of the rule (cycle=(l, o))∪X→Y is the ratio of the fraction of all transactions that occurred within all the time units tfor which (o=i mod l) holds and that contain both X and Y to all transactions. Similarly, the confidence of this rule is the ratio of the fraction of all transactions that occurred within all the time units tfor which (o=i mod 1) holds that contain both X and Y to the fraction of all transactions occurred within all the time units tfor which (o=i mod 1) holds that contain X.
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Again, this approach may mistakenly detect non-existing cycles. For example, this approach may detect that (cycle=(l, o))∪X→Y holds (i.e., X→Y has a cycle c), although X→Y holds only within some time units t's for which (o=i mod 1) holds, but not within all.
A Sequential Algorithm
Proc.
Intl.l Conf VLDB
Proc. of the
st Intl.l Conf. on Very Large Data Bases
th
Discovering cyclic association rules in accordance with one illustrative technique involves generating rules in each time unit and then applying a pattern matching algorithm a described below to discover cycles. We refer to this approach as the sequential algorithm. Useful rule-generating techniques to be applied in time units include some based on Agrawal, R., and R. Srikant, “Fast Algorithms for Mining Association Rules,” 20, Santiago, Chile, 1994 (hereinafter “Agrawal, et al 94”), and on descriptions in Savasere, A, E. Omiecinski, and S. Navathe. “An Efficient Algorithm for Mining Association Rules in Large Databases,” 21, pages 432-444, Zurich, Switzerland, September 1995. In particular, the Agrawal, et al 94 paper presents the so-called Apriori algorithm. These papers and the above-cited Agrawal, et al 93 papers are hereby incorporated by reference as if set out in their entirety in this description.
Existing algorithms (such as the Apriori algorithm) typically discover the association rules in two steps. In the first step, large itemsets are generated, and in the second step association rules are generated from the large itemsets. The running time for generating large itemsets can be substantial, since calculating the supports of itemsets and detecting all the large itemsets for each time unit grows exponentially in the size of the large itemsets. To reduce the search space for the large itemsets, the existing algorithms exploit the following property: “Any superset of a small itemset must also be small.” (Recall the definitions of “large” (frequent) itemsets given above; a “small” itemset is one that is not large.)
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Existing algorithms typically calculate support for itemsets iteratively and prune all the supersets of a small itemset during the consecutive iterations. Let us refer to this pruning technique as support-pruning. In general, these algorithms execute a variant of the following steps in the kiteration:
1. The set of candidate k-itemsets is generated by extending the large (k−1)-itemsets discovered in the previous iteration (support-pruning).
2. Supports for the candidate k-itemsets are determined by scanning the database.
3. The candidate k-itemsets that do not have minimum support are discarded and the remaining ones constitute the large k-itemsets.
The idea is to discard most of the small k-itemsets during the support-pruning step so that the database is searched only for a small set of candidates for large k-itemsets.
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In the second step, the rules that exceed the confidence threshold conare constructed from the large itemsets generated in the first step with one of the existing algorithms. In an illustrative embodiment of our sequential algorithm, we apply the Apriori and the ap-genrules algorithms from Agrawal, et al 94 to each time unit. Once the rules of all the time units have been discovered, cycles are detected. If r is the number of rules detected, the complexity of the cycle detection phase has an upper bound of O(r·n·l) where n is the number of time units and lis the maximum cycle length of interest (see below in the section Cycle Detection).
In practice, if all the rules in each time unit fit into main memory of a single computer, then the running time of the cycle detection phase has typically been found to be feasible. However, if the rules in all the time units do not fit into main memory, then the overhead of I/O operations substantially increases the running time of the cycle detection phase (see below), and therefore the sequential algorithm may be less desirable in some applications for detecting cyclic association rules.
FIG. 3
FIG. 3
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shows a flowchart for an illustrative method using a sequential algorithm in accordance with one aspect of the present invention. This and other methods described herein may be practiced in a computer or network of computers as noted above. In , after starting at element , the process is shown entering an initialization block during which typical user-specified (or default) process parameters are read and stored in computer memory. In some cases, the user may specify more or fewer parameters, as will befit the nature of the mining to be undertaken and the programming language or toolkit used to effect the user requirements. The database containing the transaction records to be mined is then logically segmented (step ) to reflect the time units selected by the user. In appropriate cases, the database may be physically segmented between different memories or even different computers. To further initialize the mining process, the item parameter i is illustratively set to zero (step ) for the presently described process representation.
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After completing initialization steps , processing is accomplished in accordance with the loop of steps , and . Specifically, a test is made at step for the current value of i; if i<i, then step is performed and i is incremented at step . Processing at step involves determination of rules in time unit i (e.g., using the well-known a priori algorithm, but with the additional application of support pruning as described above. A typical output of is a binary sequence of the type described above, where at the ith bit position in the sequence a 1 indicates that the currently considered rule meets specified support and confidence thresholds. A 0 in the ith bit position in such sequences indicates that the support and confidence (for a particular rule) for the ith time segment does meet the support and confidence thresholds. When the test at step for i=iyields a positive (yes) response, then processing is passed to block for determination of cycles for the rules determined at step .
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elaborates the cycle determination step in FIG. . In , block represents the bit sequence length initialization for sequences derived in the processing of FIG. . Initially, it proves convenient (as shown by block ) to assume that the sequences have all possible cycles (j, k). As will become apparent, cycles will then be selectively eliminated to yield the final result. To effect this elimination, the bit position index m is initially set to 0 at step and the loop , and is performed until a yes result is obtained upon performing the test for m=n−1 at step . For each pass through this loop, bit position m is tested for a 0 value. When this 0 value is determined at step all cycles (j, m mod j) are eliminated for 2 □ j □ m. Processing of the remaining (j, k) cycles then proceeds to block for the elimination of non-large cyles.
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FIG. 5
The steps illustratively employed for the elimination of non-large cycles is shown in FIG. . Specifically, it proves convenient to order the cycles (j,k) in order of increasing j, as reflected by block in FIG. . Then, as reflected by block in , all cycles (j′, k′) for which j′ is a multiple of j and k=k′ mod j are eliminated. The resulting cycles then reflect the cyclic characteristics of the original data.
Cycle Pruning Cycle Skipping and Cycle Elimination
A major portion of the running time of the sequential algorithm is typically spent in calculating support for itemsets. We now present three techniques—cycle pruning, cycle skipping, and cycle elimination to prune the number of itemsets for which the support must be calculated. These techniques rely on the following observation: “A cycle of the rule X→Y is a multiple of a cycle of itemset X∪Y.” Eliminating cycles as early as possible therefore substantially reduces the running time of cyclic association rule detection. Each of these techniques will now be discussed in turn.
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Cycle skipping is a technique for avoiding counting the support of an itemset in time units which cannot be part of a cycle of the itemset. Cycle-skipping is based on the observation: “If time unit tis not part of a cycle of an itemset X, then there is no need to calculate the support for X in time segment D[i].” However, cycle skipping is useful only if we have information about the cycles of an itemset X. But the cycles of an itemset X can be computed exactly only after we compute the support of X in all the time segments.
In order to avoid this self-dependency, it proves useful to approximate the cycles of itemsets. To do this, we use a technique we call cycle pruning. It is based on the property: “If an itemset X has a cycle (l, o), then any of the subsets of X has the cycle (l, o).” (Thus, e.g., for the itemset coffee∪doughnuts to have a cycle (l, o), itemset coffee must have the cycle (l, o).) This property implies that any cycle of itemset X must be a multiple of a cycle of an itemset that is a subset of X. This also implies that the number of cycles of an itemset X is less than or equal to the number of cycles of any of X's subset.
Therefore, one can arrive at an upper bound on the cycles that an itemset X can have by looking at all the cycles of the subsets of X. By doing so, we can reduce the number of potential cycles of itemset X, which, in turn (due to cycle-skipping), reduces the number of time units in which we need to calculate support for X. Thus, cycle-pruning is a technique for computing the candidate cycles of an itemset by merging the cycles of the itemset's subsets.
However, it is possible in some cases that we cannot compute the candidate cycles of an itemset, e.g., when dealing with singleton itemsets. In these cases, it proves convenient to assume that an itemset X has every possible cycle and therefore, calculate the support for X in each time segment D[i] (except the time units eliminated via support-pruning). This method is used in an illustrative embodiment of the sequential algorithm.
If we know that 010 is the only large cycle of item A, and 010 is also the only large cycle of item B, then cycle pruning implies that the itemset consisting of items A and B can have only the cycle 010 or its multiples. Cycle skipping indicates that we do not need to calculate the support for A∪B in every time segment but only in every third one starting with D[1].
If we know that 010 is the only large cycle of item A and 001 is the only large cycle of item B, then cycle-pruning implies that the itemset A∪B cannot have any cycles. Cycle skipping indicates that we do not need to calculate the support for A∪B in any of the time segments.
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We now introduce one more optimization technique we call cycle elimination that can be used to further reduce the number of potential cycles of an itemset X. Cycle elimination is used to eliminate certain cycles from further consideration once we have determined they cannot exist. Cycle elimination relies on the property: “If the support for an itemset X is below the minimum support threshold supin time segment D[i], then X cannot have any of the cycles (j, i mod j), l≦j≦l.” Cycle-elimination enables us to discard cycles that an itemset X cannot have as soon as possible—as demonstrated in the following example.
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If the maximum cycle length of interest is land the support for itemset A is below the threshold supin the first ltime units, then cycle-elimination implies that A cannot have any cycles. Cycle-skipping indicates that there is no need to calculate the support for A in time units greater than l.
Interleaved Algorithm
We now present an alternative algorithm, which we refer to as the interleaved algorithm, for discovering cyclic association rules. The interleaved algorithm consists of two phases. In the first phase, the cyclic large itemsets are discovered. In the second phase, cyclic association rules are generated.
In the first phase, the search space for the large itemsets is reduced using cycle-pruning, cycle-skipping and cycle-elimination as follows. (For k=1, all possible cycles are initially assumed to exist for each single itemset.) For each k, k>1:
1. Cycle-pruning is applied to generate the potential cycles for k-itemsets using the cycles for (k−1)-itemsets.
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2. Time segments are processed sequentially. For each time unit t:
2.1 Cycle-skipping determines, from the set of candidate cycles for k-itemsets, the set of k-itemsets for which support will be calculated in time segment D[i].
2.2 If a k-itemset X chosen in Step 2.1 does not have the minimum support in time segment D[i], then cycle-elimination is used to discard each cycle c=(l, o), for which (o=i mod l) holds, from the set of potential cycles of X.
This process terminates When the list of potential cycles for each k-itemset is empty. Cycle-pruning, cycle-skipping and cycle-elimination can reduce the candidate k-itemsets for which support will be counted in the database substantially, and therefore can reduce the running time of calculating the large itemsets. This is demonstrated by the following example.
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Suppose that the length of the longest cycle we are interested in is l=6 and 1110000000111111111 and 1111010111111111111 represent items A and B, respectively. If the sequential algorithm is used, then the support for A and B will be calculated in all the time segments and the support for A∪B will be calculated in time segments -, - (due to support-pruning). If the interleaved algorithm is used, then the support for A will be calculated in time segments - (due to cycle-elimination and cycle-skipping), whereas the support for B will be calculated in all the time segments, and since A has no cycles, A∪B cannot have any cycle (due to cycle-pruning), and the support for A∪B will not be calculated in any of the time units (due to cycle-skipping).
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In the second phase of the interleaved algorithm, the cyclic association rules can be calculated using the cycles and the support of the itemsets found in the first phase without additional scanning of the database. Interleaving cycle detection with large itemset detection also reduces the overhead of rule generation phase. This is because a cycle of the rule X∪Y must be a multiple of a cycle of itemset X∪Y, and at the end of the first phase of the interleaved algorithm we already know the cycles of large itemsets. Thus, the set of candidate cycles for a rule X→Y initially consists of the set of cycles of the itemset X∪Y. As a result, we need to calculate the confidence of a rule X→Y only for time units that are part of cycles of X∪Y. Moreover, whenever we encounter a time unit tin which this rule does not have minimum confidence con, we can eliminate each other candidate cycle of this rule for which (j, i mod j), 1≦j≦m holds. Once the cycles of the association rules are detected, the cycles that are not large can be eliminated (see Cycle Detection, below).
FIG. 6
FIG. 3
shows a flowchart for an illustrative method using an interleaved algorithm in accordance with the above teachings. As was the case for the method illustrated by the flowchart of , the present illustrative interleaved method may be practiced using a variety of computers or networks of computers.
FIG. 6
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The process of , after starting at element , uses an initialization block, illustratively of the same general type used in the flowchart of FIG. . Thus step represents the initialization and reading of parameters as for the sequential processing of FIG. . The index k is initialized at k=1 at step and step determines the large itemsets for the k=1 (singleton) case by examining D[0] through D[max−1]. Step corresponds to the determination of cycles for the singleton itemset case.
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At step the k variable is incremented and the general cycle-pruning techniques are applied at step to determine candidate k-itemset cycles from (k−1)-itemset cycles. If no candidates are found then the rule detection process is applied at step and the process is concluded. If, however, the test at step reflects the presence of k-itemset candidates for the current value of k, then the steps , , , , and are performed to effect cycle skipping and cycle elimination until all values for i have been used. k is then incremented until the maximum value for k is reached, at which point rule detection is performed at step .
I/O Considerations
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Although the interleaved algorithm reduces the CPU overhead of calculating support for itemsets substantially, it incurs a higher overhead for I/O operations when compared to the sequential algorithm. To reduce such consequences, in accordance with other embodiments of the present invention, each time a time segment D[i] is accessed, calculation of cycles and support for k, (k+1), . . . , and (k+g)-itemsets, for some g>1, is advantageously combined. In this case, cycle-pruning for each (k+j)-itemset, 0≦j≦g, is done by merging the cycles of (k−1) subsets of the (k+j)-itemset. That is, the set of candidate cycles of a (k+j)-itemset consists of the intersection of the sets of cycles of all (k−1) subsets of the itemset. While scanning a time segment D[i], first supports for the k-itemsets that have candidate cycles into which time unit tparticipates are calculated. If the support for a candidate k-itemset X is below sup, then cycle-elimination is applied not only to the candidate cycles of itemset X, but also to each (k+j)-itemset, 0≦j≦g, that is a superset of X. Note that cycle elimination eliminates potentially more (k+j)-itemsets compared to support-pruning. This is because support-pruning eliminates (k+j)-itemsets that are supersets of X only in D[i] whereas cycle-elimination eliminates (k+j)-itemsets that are supersets of X not only in D[i] but potentially also in other time segments following D[i]. Once supports for the candidate k-itemsets in D[i] are calculated, then supports for the candidate (k+1)-itemsets in D[i] are calculated similarly, followed by supports for the candidate (k+2)-itemsets in D[i], and so on. Those skilled in the art will select preferred values for g, depending, e.g., on system configuration and the nature of the data records.
Cycle Detection
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Given a binary sequence of length n and the maximum cycle length of interest l, the running time of detecting all cycles with lengths less than or equal to lof the binary sequence has an upper bound of O(l·n) operations. We now present a two-step approach to detecting cycles. Initially, the set of candidate cycles contains all possible cycles. In the first step, the sequence is scanned, and each time a zero is encountered at a sequence position i, candidate cycles (j, i mod j), 1≦j≦m are eliminated from the set of candidate cycles. The first step completes whenever the last bit of the sequence is scanned or the set of candidate cycles becomes empty, which ever is first. In the second step, large cycles (i.e., cycles that are not multiples of any existing cycles are detected). A straight-forward approach to eliminating cycles that are not large is: starting from the shortest cycle, for each cycle c=(l, o), eliminate each other cycle c=(l, o) from the set of cycles, if lis a multiple of land (o=omod l) holds. The illustrative sequential algorithm typically uses this approach to detect the cycles.
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However, if we know initially, or at any time during scanning the sequence that some of the cycles cannot exist in the sequence (e.g. due to cycle-pruning or cycle-elimination), the cycle detection procedure can be optimized by skipping sequence positions that cannot be part of any of the candidate cycles. That is, instead of scanning the sequence sequentially, we can skip the bit positions that are not part of the candidate cycles (i.e., cycle-skipping). For example, if lis three, and we know initially that 01, 010 and 001 cannot be cycles of a given sequence (e.g., due to cycle-pruning), then we need not scan bit positions , , , , etc. Also, while scanning the sequence, if we also eliminate candidate cycle 100 (i.e., cycle-elimination), we can skip scanning every second bit of the sequence starting at that point. The interleaved algorithm advantageously employs these optimization techniques (cycle-pruning, cycle-elimination and cycle-skipping) to reduce the overhead of cycle detection and, importantly, the overhead of calculating support for itemsets, since the interleaved algorithm “interleaves” both cycle detection and support calculation for itemsets.
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The cycle detection process can be further optimized by considering a candidate cycle c=(l, o) only when there is no other candidate cycle c=(l, o) remaining such that cis a multiple of c(i.e., ldivides land o=omod l). Other optimizations of cycle detection based on the present teachings will occur to those skilled in the art.
Additional Implementation Details
In this section, we present illustrative implementation components and methods for discovering cyclic association rules in embodiments of the present invention. Though many particular algorithms and their variants may be used as a basic data mining algorithm, it proves convenient in embodiments of the present invention to use the apriori algorithm from Agrawal, et al 94 for this purpose. The sequential algorithm is based directly on apriori, with optimizations to speed up the counting of support of itemsets of size 2. Thus, we use to advantage an array for this instead of a hash-tree when memory permits. We found the array to be a much faster technique for discovering 2-itemsets.
The interleaved algorithm uses a well-known hash-tree technique as described in Agrawal, et al 94, to store the large itemsets, their patterns and support counts. The interleaved algorithm also advantageously uses a temporary hash-tree during the processing of an individual time segment. Candidate generation (generation of itemsets of size k+1 and their candidate cycles from itemsets of size k) is employes cycle pruning. Appendix 1 presents the first phase of the interleaved algorithm (cyclic large itemset detection) in psuedo-code. After that, it proves advantageous to apply a generalization of the rule generation procedure in Agrawal, et al 94 for cyclic association rule generation.
Memory Management
As noted above the sequential algorithm advantageously runs the apriori algorithm on each time segment. In order to determine the cycles of the association rules, we need to determine the binary sequence corresponding to each association rule. If there is space in memory to hold a binary sequence for each association rule, we can store the rules and their binary sequences in a hash tree. After generating all the rules over all the time segments, we run cycle detection algorithms.
However, if there is not enough memory to store the rules and their binary sequences, the rules are advantageously written to disk as generated in each time unit. When all association rules for all the time segments are found, the binary sequences for each individual association rule are constructed. In order to do this, we merge the rules from the different time segments. Once this merging is done, we can run the cycle detection algorithms.
Finally, if we do not have enough memory to store all the data structures needed by the apriori algorithm, we have to use one of the overflow management techniques suggested in Agrawal, et al.
Like the apriori algorithm, the interleaved algorithm has two distinct phases. In the first phase, all large itemsets with cycles have their supports counted in the appropriate time segments. In the second phase, rules are generated using the cycle and support information of the large itemsets.
For the first phase, the interleaved algorithm proceeds “level-by-level” to determine itemset support. It first determines the itemset support for singleton candidate itemsets, generates cycles for them, then generates itemsets of size 2 and their potential cycles, etc. In this phase, the interleaved algorithm requires enough memory to hold all large itemsets of a particular size and their support counts in memory. (In addition, it advantageously stores the new candidates and their “potential” cycles. The size of the latter is usually much smaller.) If there is not enough memory, the support counts are typically broken up into chunks and written to disk. After processing of all the time segments, the support counts are merged in memory.
For the cyclic rule generation phase, if there is space in memory to hold all the large itemsets and their support counts for all the time units, rule generation can run entirely in memory. However, if there is a shortage of memory and space is available to hold only a single level of large itemsets and their support counts, we can generate rules in a level-by-level fashion as well starting at the level of the largest itemset. For doing this, we can use a modification of the ap-genrules procedure in Agrawal, et al that we call Level_GenRuleCycles as shown in Appendix 2. Level_GenRuleCycles is a set oriented rule generation procedure that creates rules such that all rules needing to look at the support counts of k-itemsets are generated during one iteration of the outer while loop. (Note that this procedure can be profitably used, instead of ap-genrules, for generating association rules when memory is limited.)
ABCD
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For example, suppose we have the large itemset ABCD with a cycle 001. Initially, ruleList is the empty set and in the first iteration gets set to {ABCD, sup-array, {001}, {}}. In the next round, ABC→D, ABD→C, ACD→B and BCD→A are generated and tested. This round keeps the support counts of all 3-itemsets in memory. Suppose only ABC→D and ABD→C have cycles. ruleList becomes {{ABCD, sup-array, {001 }, {ABC→D, ABD→C}}}. (Of course, large itemsets ABC and ABD will get added to prev, but we ignore that here to keep the example small.) In the next round, only the rule AB→CD is generated. This round keeps the support counts of all the 2-itemsets in memory. If AB→CD has a cycle, ruleList is transformed to {{ABCD, sup-array, {001}, {AB→CD}}} and vanishes in the next round.
This algorithm requires only one member of ruleList to be in memory at any time. If the support counts of a particular level do not fit into memory as well, one has to sort ruleList according to the candidate rules that it stores and merge the itemset support counts in order to generate cyclic association rules.
In typical applications, the interleaved algorithm performs at least as well, and often times, significantly better than the sequential algorithm. Thus, for example, in illustrative examples relative performance enhancements for the interleaved algorithm range from 5%, when support is very high, to several hundred percent, when large itemset sizes are over 5. Much of this advantage comes from the decreased I/O costs possible with the interleaved algorithm. Further, the interleaved algorithm is found to readily scale to accommodate large databases.
While the term “transaction” has been used in connection with particular types of transactions, such as supermarket or other retail transactions, it should be understood that the present invention covers processing of transactions of any kind. Likewise, though transaction item values have been illustratively indicated as occurring in a single record or file, particular implementations will store transaction data in varying ways, including storing such data in a plurality of files.
/* This algorithm uses two hash-trees. itemset-hash-tree contains candidates of size k, their potential cycles, and space to store support counts for the relevant time units. An “active” itemset at time unit t is an itemset that has a cycle that t participates in. tmp-hash-tree, during the processing of time segment t, contains all the itemsets that are active in t. */
initially, -itemset-hash-tree contains singleton itemsets and all possible cycles
k=1
while (there are still candidates in itemset-hash-tree with potential cycles)
for t=0 to n−1
insert active itemsets from itemset-hash-tree into tmp-hash-tree // cycle
skipping measure support in current time segment for each itemset in
tmp-hash-tree
forall l ∈ tmp-hash-tree
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if (sup<sup)
then delete corresponding cycles of itemset l // cycle elimination
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else insert (l, sup, t) into itemset-hash-tree
l
// this just inserts a (sup, time) entry in one of itemset l's fields
end forall
empty tmp-hash-tree
endfor
verify actual cycles of each member of itemset-hash-tree
generate new candidates of size k+1 using cycle pruning
k=k+1
empty itemset-hash-tree after copying it to disk
insert new candidates into itemset-hash-tree
endwhile
Procedure Level_GenRuleCycles()
level=size of the largest itemset
/* ruIeList is a list of records that have four fields. The first three fields contain an itemset name, the support array for the itemset, and the list of cycles for the itemset.
The fourth field is a list of candidate rules generated from the itemset that are known to have cycles. */
ruIeList={} // “ruleList” is the current list of quintuplets used for generating rules.
while (level≧1)
read in support counts and cycles of large itemsets of size level
newRuIeList={}
forall lItem ∈ ruleList do
if (lItem's itemset is being used to generate rules for the first time)
then generate singleton rules
else generate candidate rules using apriori-gen on lItem's current rules verify cycles for each rule generated and discard rules without cycles.
lItemNew=lItem with old rules replaced by the new rules
newRuIeList=newRuIeList+lItemNew
endforall
ruleList=newRuIeList+quintuplets created from large itemsets at current level
level−−
endwhile | |
What Does it Mean to be an Extroverted Writer?
Have you ever noticed that most writers are introverts? There’s Edgar Allan Poe, J. D. Salinger, Virginia Woolf, Sylvia Plath, J. K. Rowling, John Green, and the list goes on and on. If you don’t believe me, try to name at least five authors you consider to be extroverted. It’s impossible, right?
A Word from John Green, Introverted Writer
John Green, author of The Fault in our Stars and Looking for Alaska, says, “Writing is something you do alone. It’s a profession for introverts who want to tell you a story but don’t want to make eye contact while doing it.”
But what about the extroverts, like myself, who are aspiring writers? Are we going against our personal nature to pursue a calling we weren’t designed to fulfill? Are we at a disadvantage to our fellow introverted writers?
Extroversion vs. Introversion
I say no! If you’re extroverted and love writing, do not be fooled. I agree that writing often is something done alone, and introverts tend to thrive in this profession. But that doesn’t mean extroverts can’t be writers. It also doesn’t mean that extroverts should convert into something they’re not in order to be successful writers.
If you’re extroverted, you gain energy from your surroundings: people, social events, movies, current events, etc. You prefer environments that are stimulating (full of energy). In contrast, introverts draw energy from within themselves, and stimulating environments tend to wear them out.
Using Extroversion as a Tool to Successful Writing
With this in mind, how can we extroverts use our extroversion as a tool to better our writing? Here are some things I’ve done that have helped me with my writing.
1) Be involved and learn from your experiences.
Do things other than writing and learn from them! Whether you are playing sports, playing video games, going to the movies with friends, listening to music, playing an instrument, joining a club, or doing something you’re passionate about (other than writing), always engage in something that will fill you. As extroverts, it’s easier to write from an experience. How you interpret that experience (using it in a fiction or nonfiction context) is completely up to you.
2) Meet people and apply what you learn to your characters.
Use your writing ability to meet and socialize with people to strengthen your character development skills. Watch their mannerisms, listen to their dialect, and learn what makes their personality unique.
You can even write down certain phrases or behaviors that stick out to you during the conversation. By better understanding the people around you, you will create more realistic characters and dialogue within your own writing.
3) Write in Different Places.
Many authors tell aspiring writers to always write in one specific area so that they get into the “write” mindset. Personally, I find it easier to write when I go somewhere out of the norm. New places offer new experiences and new ideas, no matter how insignificant it may be. It keeps my mind moving and thinking in different ways which especially helps me when I'm in a rut with my writing.
4) Use your network of relationships as personal editors.
The editing process can be painful, especially when you surrender your writing to a fellow colleague or friend who is sharp with a red pen. However, it’s beneficial for every writer, extrovert or not, to gain another person's perspective of your writing.
Extroverts tend to value having an abundance of friends. With this in mind, it’s important to make use of these relationships to develop your writing. Do not send out your manuscripts and papers to everyone you meet. Instead, send your work to a collection of friends you know you can trust and gain constructive criticism to better understand your own strengths and weakness.
Writing doesn’t belong to any one type of person, extroverted, introverted, or something in between. Writing is art with words, and it belongs to anyone who possess the passion and drive to practice and perfect it.
Take the quiz!
What kind of writer are you?
Extrovert/ Introvert Quiz
- Self Tests by Psychology Today
If you don't know what type you are or if your looking for some reassurance, take the extreovert/ introvert quiz provided through this link.
Are you an extroverted or introverted writer? How does this affect your writing style and craft?
Answer below in the comments section.
© 2015 Noah Clayton
Comments
I really don't know what I am, but writer's do write alone even while in a crowded room ..This isn't to say that extrovert writers devote less time to writing, but in general introverts spend more time alone and have the option to use their time differently.. you make sound points and this hub is very interesting so glad Jodah shared it, because I would have missed it.. Frank
Interesting hub, Noah. I am without doubt an introverted writer. I actually prefer to communicate through writing than speaking. Although I am better now at thing like speaking in public than I used to be, it was a matter of forcing myself out of my comfort zone. I do however don't see writing as purely a profession for introverts. As you rightly state extroverts are more likely to be out in public mixing with others and gaining valuable life experiences that they can write about. Introverted writers probably rely on their inner feelings, emotions, music and the like for their inspiration rather than actual experiences. Some writer may however just appear introverted because they spend so much time writing they don't have much time to participate in real world activities. | https://hubpages.com/literature/What-Does-it-Mean-to-be-an-Extroverted-Writer |
The present invention relates to a traction control apparatus for preventing slippage of driving wheels in an acceleration state.
An apparatus for preventing slippage of driving wheels of a vehicle in an acceleration state, as disclosed in U.S.P. No. 4,637,487, or the like, is known. In such an apparatus, a main throttle valve whose opening is controlled in cooperation with an accelerator pedal and a sub throttle valve whose opening is electrically controlled are arranged in an air intake path of an engine. When slippage of driving wheels is detected, the opening of the sub throttle valve is controlled to be decreased, thereby reducing an engine output, and eliminating slippage of the driving wheels.
However, in this apparatus, when slippage of driving wheels is detected, the engine output is reduced to prevent slippage of driving wheels, as described above. When slippage of the driving wheels is no longer detected and control for reducing the engine output is stopped, slippage of the driving wheels occurs again.
It is an object of the present invention to provide a traction control apparatus wherein when slippage of driving wheels is detected, the driving wheels are braked, a target engine output is determined by correcting a reference target torque according to a driving state of a vehicle by a correction torque corresponding to a slip value of driving wheels, and an engine output is controlled to reach the target engine output.
According to the present invention, a traction control apparatus comprises:
drive state detecting means for detecting a drive state of a vehicle;
driving wheel velocity detecting means for detecting a driving wheel velocity of the vehicle;
driven wheel velocity detecting means for detecting a driven wheel velocity of the vehicle;
reference velocity setting means for setting a reference velocity on the basis of an output from said driven wheel velocity detecting means;
slip value detecting means for detecting a slip value of the driving wheel on the basis of a difference between the driving wheel velocity and the reference velocity;
control start instruction means for outputting at least an engine control start signal when a slip state of the driving wheel including at least the slip value satisfies a predetermined control start condition;
vehicle acceleration calculating means for calculating a vehicle acceleration of the vehicle on the basis of the output from said driven wheel velocity detecting means;
reference drive torque calculating means for calculating a reference drive torque on the basis of an output from said vehicle acceleration calculating means;
target output torque setting means for determining a target output torque of the engine in accordance with an output from said reference drive torque calculating means;
correction torque setting means for setting a correction torque on the basis of an output from said slip value detecting means;
target output torque correcting means for correcting the target output torque in accordance with an output from said correction torque setting means; and
drive torque control means for, when the engine control start signal is output, controlling an engine output of the vehicle in accordance with the corrected target output torque to control the drive torque of the driving wheel.
According to the present invention, when slippage of driving wheels is detected, the driving wheels are braked, a target engine output is determined by correcting a reference target torque according to a driving state of a vehicle by a correction torque corresponding to a slip value of driving wheels, and an engine output is controlled to reach the target engine output. Therefore, a traction control apparatus with high accuracy can be provided.
Fig. 1A is a diagram showing an overall arrangement of a traction control apparatus according to a first embodiment of the present invention;
Fig. 1B is a diagram showing a detailed arrangement of a traction controller shown in Fig. 1A;
Figs. 2A to 2C are block diagrams showing control of the traction controller shown in Fig. 1A in units of functional blocks;
Fig. 3 is a graph showing the relationship between a centripetal acceleration GY and a variable KG;
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Fig. 4 is a graph showing the relationship between a time after traction control is started and a variable KT;
Fig. 5 is a graph showing the relationship between a vehicle velocity VB and a variable KV;
Fig. 6 is a graph showing the relationship between and a changing value GFR (GFL) of a slip value DV as a function of time and a braking hydraulic pressure variation ΔP;
Fig. 7 is a graph showing the relationship between an engine speed NE and an opening of a main throttle valve THm;
Fig. 8 is a graph showing changes in driving (front) wheel velocity VF, reference driving wheel velocity Vφ, and vehicle velocity VB as a function of time;
Fig. 9 is a graph showing the relationship between a slip rate S and a friction coefficient µ of a road surface;
Fig. 10 is a graph showing the relationship between a vehicle acceleration GBF and a variable K1;
Fig. 11 is a graph showing the relationship between the slip value DV and a coefficient KI;
Fig. 12 is a graph showing the relationship between the slip value DV and a coefficient Kp;
Fig. 13 is a graph showing the relationship between a target torque Tφ′ and an equivalent throttle opening ϑs′;
Fig. 14 is a graph showing the relationship between the engine speed Ne and a lower limit of an opening ϑs of a sub throttle valve THs;
Fig. 15 is a graph showing the relationship between the centripetal acceleration GY and variation of coefficient Kp ΔKp;
Fig. 16 is a view showing the arrangement of the main throttle valve THm and a sub throttle valve THs;
Fig. 17A is a diagram showing an overall arrangement of a traction control apparatus according to a second embodiment of the present invention;
Fig. 17B is a diagram showing a detailed arrangement of a traction controller shown in Fig. 17A;
Figs. 18A to 18C are block diagrams showing control of the traction controller shown in Fig. 17A in units of functional blocks;
Fig. 19 is a graph showing the relationship between a centripetal acceleration GY and a variable KG;
Fig. 20 is a graph showing the relationship between the centripetal acceleration GY and a variable Kr;
Fig. 21 is a graph showing the relationship between the centripetal acceleration GY and a slip value Vg;
Fig. 22 is a graph showing the relationship between a changing value ΔGY of the centripetal acceleration GY as a function of time and the slip value Vd;
Figs. 23 to 28 are graphs showing the relationship between a vehicle velocity VB and a coefficient KV;
Fig. 29 is a graph showing a change in coefficient KB after traction control is started;
Fig. 30 is a graph showing the relationship between an changing value GFR (GFL) of a slip value DV as a function of time and a braking hydraulic pressure variation ΔP;
Figs. 31 and 34 are graphs showing the relationship between a slip rate S and a friction coefficient µ of a road surface;
Fig. 32 is a graph showing the relationship between a lower limit Tlim of a target engine torque and a time (t1) after traction control is started;
Fig. 33 is a graph showing the relationship between the vehicle velocity VB and the lower limit Tlim of the target engine torque;
Fig. 35 is a view showing a state of a vehicle when it is turned;
Fig. 36 is a diagram showing an overall arrangement of a traction control apparatus according to a third embodiment of the present invention;
Fig. 37 is a circuit diagram showing the principle of a differential transformer type G sensor;
Fig. 38 is a graph showing an output voltage of a lateral G sensor; and
Fig. 39 is a drive state detecting means.
This invention can be more fully understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:
A traction control apparatus for a vehicle according to a first embodiment of the present invention will now be described with reference to the accompanying drawings. Fig. 1A is a diagram showing a traction control apparatus for a vehicle. Fig. 1A illustrates a front-wheel drive vehicle. In Fig. 1A, reference symbol WFR denotes a front right wheel; WFL, a front left wheel; WRR, a rear right wheel; and WRL, a rear left wheel. Reference numeral 11 denotes a wheel velocity sensor for detecting a wheel velocity VFR of the front right wheel (driving wheel) WFR; 12, a wheel velocity sensor for detecting a wheel velocity VFL of the front left wheel (driving wheel) WFL; 13, a wheel velocity sensor for detecting a wheel velocity VRR of the rear right wheel (driven wheel) WRR; and 14, a wheel velocity sensor for detecting a wheel velocity VRL of the rear left wheel (driven wheel) WRL. The wheel velocities VFR, VFL, VRR, and VRL detected by the wheel velocity sensors 11 to 14 are input to a traction controller 15. The traction controller 15 performs control of preventing slippage of driving wheels in an acceleration state. An engine 16 has a main throttle valve THm and a sub throttle valve THs, as shown in Fig. 16. In a normal drive mode, the main throttle valve THm is operated by an accelerator pedal to adjust an engine output. In a traction control mode, a throttle opening ϑs of the sub throttle valve THs is controlled to control the engine output. Reference numeral 17 denotes a wheel cylinder for braking the front right wheel WFR; and 18, a wheel cylinder for braking the front left wheel WFL. Supply of a pressurized oil from an accumulator 19 to the wheel cylinder 17 is performed through an inlet valve 17i, and exhaustion of the pressurized oil from the wheel cylinder 17 to a reservoir 20 is performed through an outlet valve 17o. Supply of the pressurized oil from the accumulator 19 to the wheel cylinder 18 is performed through an inlet valve 18i, and exhaustion of a pressurized oil from the wheel cylinder 18 to the reservoir 20 is performed through an outlet valve 18o. A normally-open right shut valve 202R is arranged on a right oil path 201R between a master cylinder 201 and the inlet valve 17i, and a normally-open left shut valve 202L is arranged on a left oil path 201L between the master cylinder 201 and the inlet valve 18i. The inlet valves 17i and 18i and the outlet valves 17o and 18o and shut valves 202R and 202L are open/close-controlled by the traction controller 15.
The traction controller 15 receives a shift signal SHT from a transmission controller 151 for controlling switching of shift positions of an automatic transmission 16m. The SHT signal indicates a shift position of the automatic transmission 16m. The traction controller 15 also receives an engine speed signal Ne of the engine and an opening signal ϑm of the main throttle valve THm shown in Fig. 16.
The detailed arrangement of the traction controller 15 shown in Fig. 1A will now be described with reference to Fig. 1B. The traction controller 15 comprises an MPU (micro processor unit) 15p including various registers, an ALU (arithmetic and logic unit), and the like, a memory 15m for storing a traction control program, various maps, coefficient data, variable data, counters, and flags, and the like.
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More specifically, the memory 15m stores the traction control program whose control content is shown in Figs. 2A and 2B in units of functional blocks, a variable KG shown in Fig. 3, a variable KT shown in Fig. 4, a variable KV shown in Fig. 5, a GFR (GFL) - ΔP map shown in Fig. 6, a map showing the opening ϑm of the main throttle valve THm shown in Fig. 7, a variable Kl shown in Fig. 10, a coefficient KI shown in Fig. 11, ΔKp shown in Fig. 12, a Tφ′ - ϑs′ map shown in Fig. 13, a ϑs map shown in Fig. 14, a ΔKp map shown in Fig. 15, a vehicle weight W and a wheel radius Re, correction torques TSn and TPn, a target torque Tφ, a braking time FR of the right driving wheel, a braking time FL of the left driving wheel, a present vehicle acceleration GB, an immediately preceding vehicle acceleration GB, a present vehicle acceleration GBF passed through a filter, an immediately preceding vehicle acceleration GBF passed through the filter, a timer t1 for counting a time t1 after traction control is started, a control flag CNTl which is set when a start condition for starting engine output control is established and is reset when an end condition for ending the control is established, a control flag CNT2 which is set when a start condition for starting braking control is established and is reset when an end condition for ending the braking control is established, and a shift change flag CHFLG to which "1" is set for a predetermined period of time after a shift change operation is performed.
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The detailed arrangement of the traction controller 15 will be described below with reference to the block diagrams of Figs. 2A to 2C showing the control of the traction controller 15 in units of functional blocks. The wheel velocities VFR and VFL of the driving wheels detected by the wheel velocity sensors 11 and 12 are averaged by an averaging section 21 to calculate an average wheel velocity (VFR + VFL)/2. At the same time, the wheel velocities VFR, VFL, VRR, VRL are sent to a slip rate calculating section 111. In this section 111 slip rate is calculated. And at the same time, the wheel velocities VRR and VRL are sent to a drive state detecting section 112. In this section 112, various drive conditions are detected. For example, a vehicle velocity VB and an acceleration of the vehicle and an centripental acceleration GY are calculated in section 112a, 112b, 112d on the basis of the wheel velocities VRR and VRL. And also a time after traction control by braking is started is counted in timer T. At the same time, the wheel velocities VFR and VFL of the driving wheels detected by the wheel velocity sensors 11 and 12 are sent to a low vehicle velocity selecting section (SL) 22, so that a lower vehicle velocity Vdℓ of the wheel velocities VFR and VFL is selected and output. The average wheel velocity Vde output from the averaging section 21 is multiplied with a variable K by a weighting section 23. The selected wheel velocity output from the SL 22 is multiplied with (1 - K) by a weighting section 24. The outputs from the weighting sections 23 and 24 are added to each other by an adder 25. As the variable K, a largest one of a variable KG which changes in accordance with a centripetal acceleration GY generated upon turning of a vehicle, the variable KT which changes along with the time after slip control by braking is started, and the variable KV which changes in accordance with a vehicle velocity (driven wheel velocity) VB, as shown in Figs. 3 to 5 is selected by a variable setting section 231. The wheel velocity output from the adder 25 is sent to a differential section 26 as a driving wheel velocity VF, so that a changing value of driving wheel velocity VF as a function of time, i.e., a driving wheel acceleration GW is calculated. At the same time, the velocity VF is used for calculating a slip value DV of the driving wheel, as will be described later.
The vehicle velocity VFR of the right driving wheel detected by the wheel velocity sensor 11 is sent to a subtractor 27, so that a reference driving wheel velocity Vφ (to be described later) is subtracted therefrom. The wheel velocity VFL of the left driving wheel detected by the wheel velocity sensor 12 is sent to a subtractor 28, so that the reference driving wheel velocity Vφ (to be described later) is subtracted therefrom. The output from the subtractor 27 is multiplied with KB set by the KB setting section 291 (0 < KB < 1) by a multiplier 29, and the output from the subtractor 28 is multiplied with (1 - KB) by a multiplier 30. Thereafter, the outputs from the multipliers 29 and 30 are added to each other by an adder 31 to obtain a slip value DVFR of the right driving wheel WFR. Similarly, the output from the subtractor 28 is multiplied with KB by a multiplier 32, and the output from the subtractor 27 is multiplied with (1 - KB) by a multiplier 33. Thereafter, the outputs from the multipliers 32 and 33 are added to each other by an adder 34 to obtain a slip value DVFL of the left driving wheel WFL. The slip value DVFR of the right driving wheel WFR is differentiated by a differential section 35 to calculate its change as a function of time, i.e., a slip changing value GFR. The slip value DVFL of the left driving wheel WFL is differentiated by a differential section 36 to calculate its changing value as a function of time, i.e., a slip changing value GFL. The slip changing value GFR is sent to a braking hydraulic pressure variation ΔP calculating section 37 to obtain a braking hydraulic pressure variation ΔP necessary for suppressing the slip changing value GFR with reference to the GFR (GFL) - ΔP conversion map shown in Fig. 6. Similarly, the slip changing value GFL is sent to a braking hydraulic pressure variation ΔP calculating section 38 to obtain a braking hydraulic pressure variation ΔP necessary for suppressing the slip changing value GFL with reference to the GFR (GFL) - ΔP conversion map shown in Fig. 6 (if DV > 6 km/h, a larger one of ΔP and 2 kg/cm² is employed). The variation ΔP represents a variation in amount of liquid flowing in or flowing out through the inlet valve 17i (18i) or the outlet valve 17o (18o). More specifically, as the slip changing value GFR (GFL) is increased, ΔP is increased, and the driving wheels WFR and WFL are braked to decrease a driving torque.
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The braking hydraulic pressure variation ΔP, output from the ΔP calculating section 37 for suppressing the slip changing value GFR is supplied to a ΔP - T converter 40 for calculating open times T of the inlet valve 17i and the outlet valve 17o through a switch 39. When the variation ΔP is a positive value, the open time of the inlet valve 17i is calculated, and when the variation ΔP is a negative value, the open time of the outlet valve 17o is calculated. The switch 39 is opened/closed by signal b outputted from a slip detector 391 when a start/end condition for braking the driving wheel is satisfied. For example, the following three conditions (1) to (3) are satisfied at the same time, the switch 39 is closed: (1) an idle switch SW is OFF; (2) the main throttle opening ϑm falls within a hatched region of Fig. 7; and (3) the slip value DVFR (DVFL) > 2 (km/h) and a G switch is ON, or the slip value DVFR (DVFL) > 5 (km/h). The G switch is turned on/off in accordance with GFR (GFL). When GFR (GFL) > 1g, the G switch is turned on, and when GFR (GFL) < 0.5g, it is turned off (g indicates the gravitational acceleration). The switch 39 is opened by said signal b when one of the following three conditions is satisfied: (1) the idle SW is ON; (2) an accelerator SW is ON; and (3) an ABS (Anti-lock Brake System) is operated. The signal b is also outputted to said drive state detecting section 112 so that the time after traction control by braking is counted in timer T. 411 is a right drive time accumulation section. This section 411 calculates an accumulation value ΣTir of drive times of the right inlet valve 17i set every predetermined period from the signal b is outputted until an immediately preceding period, and an accumulation value ΣTor of drive times of the right outlet valve 17o set every predetermined period. The accumulation values ΣTir and ΣTor are sent to a right drive time correcting section 412. The section 412 calculates an invalid liquid amount correction value ΔTR (= KT·ΣTor - ΣTir), KT is constant. Thereafter, the open time T of the inlet valve 17i calculated by the ΔP - T converter 40 is added to the invalid liquid amount correction value ΔTR in control by an adder 41, and the open time T of the outlet valve 17o is directly output to be used as the braking time FR of the right driving wheel WFR. Then, the driving time of the inlet valve 17i and the outlet valve 17o is controlled by a valve controller 45.
The braking hydraulic pressure variation ΔP, output from the ΔP calculating section 38 for suppressing the slip changing value GFL is supplied to a ΔP - T converter 43 for calculating open times T of the inlet valve 18i and the outlet valve 18o through a switch 42.
441 is a left drive time accumulation section. This section 441 calculates an accumulation value ΣTiℓ of drive times of the left inlet valve 18i set every predetermined period from the signal b is outputted until an immediately preceding period, and an accumulation value ΣToℓ of drive times of the left outlet valve 18o set every predetermined period. The accumulation values ΣTiℓ and ΣToℓ are sent to a left drive time correcting section 442. The section 442 calculates an invalid liquid amount correction value ΔTL (= KT·ΣToℓ - ΣTiℓ), Kt is constant. Thereafter, the open time T of the inlet valve 18i calculated by the ΔP - T converter 43 is added to the invalid liquid amount correction value ΔTL in control by an adder 44, and the open time T of the outlet valve 18o is directly output to be used as the braking time FL of the left driving wheel WFR. Then, the driving time of the inlet valve 18i and the outlet valve 18o is controlled by a valve controller 46. The correction value corrects a delay time from when a brake liquid amount is increased until a brake begins to function. In this case, since ΔTR(L) can be a maximum of 40 ms to correct the delay time, it is clipped at 40 ms.
The wheel velocities VRR and VRL of the driven wheels detected by the wheel velocity sensors 13 and 14 are sent to a high vehicle velocity selecting section (SH) 45, and a higher one of the wheel velocities VRR and VRL is selected and output as the vehicle velocity VB.
At the same time, the wheel velocities VRR and VRL of the driven wheels detected by the wheel velocity sensors 13 and 14 are sent to a drive state detecting section 112. A centripetal acceleration GY calculating section 112d of the means 112 calculate an acceleration GY as the centripetal acceleration for judging the presence/absence and degree of turning of a vehicle. And the vehicle velocity VB and travel acceleration VB′ are also calculated on the basis of the wheel velocities VRR and VRL.
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The vehicle velocity VB selected and output by the SH 45 is input to a vehicle acceleration calculating section 47 at every 15-msec sampling time T to calculate an acceleration of the vehicle velocity VB, i.e., a vehicle acceleration VB′ (GB). The vehicle acceleration VB′ is calculated by dividing a difference between a vehicle velocity VB presently input to the vehicle acceleration calculating section 47 and a vehicle velocity VB previously input to the vehicle acceleration calculating section 47 by the sampling time T. That is,
VB′ = GB = (VB - VB)/T (1)
More specifically, the vehicle acceleration calculating section 47 calculates the vehicle acceleration VB′ (GB), so that a driving torque capable of being transmitted from the driving wheel to a road surface is estimated from the vehicle acceleration VB′ of the driven wheels generated during acceleration slippage of the driving wheels. More specifically, in the case of the front-wheel drive vehicle, a force F capable of being transmitted from the driving wheels to a road surface is given by:
F = µWF = MB·VB′
(where WF is the driving wheel sharing load, and MB is the vehicle mass)
As can be seen from equation (2), when the driving wheel sharing load WF and the vehicle mass are constant values, a friction coefficient µ of a road surface is in proportion to the vehicle acceleration VB′. When the driving wheels slip and a slip rate S exceeds a point "2", it exceeds a maximum value of µ, and µ approaches a point "1", as shown in Fig. 9. When the slip rate converges, µ falls within a region between "2" and "3" through the peak "2". If the vehicle acceleration VB′ at the peak "2" can be measured, a maximum torque capable of being transmitted to a road surface having the corresponding friction coefficient µ can be estimated. The maximum torque is used as a reference torque TG.
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The vehicle acceleration VB′ (GB) calculated by the vehicle acceleration calculating section 47 is passed through a filter 48 to obtain a vehicle acceleration GBF. More specifically, when a vehicle is in a state corresponding to the position "1" in Fig. 9, it quickly shifts to a state corresponding to the position "2". Therefore, the previously calculated GBF and the presently detected GB are similarly weighted and averaged to calculate GBF = (GBF + GB)/2. Between the positions "2" and "3" in Fig. 9, in order to prolong a response time and to improve acceleration characteristics such that a larger maximum torque is estimated on the basis of an acceleration closer to an acceleration corresponding to the position "2" as much as possible, the previously calculated GBF is weighted by a larger value to calculate GBF = (27GBF + 5GB)/32. The vehicle acceleration GBF is supplied to a reference torque calculating section 49 to calculate the reference torque TG = GBF × W × Re (where W is the vehicle weight and Re is the wheel radius). The reference torque TG calculated by the reference torque calculating section 49 is supplied to a torque lower limit limiter 50, so that a lower limit Ta of the reference torque TG is limited to, e.g., 45 kg·m.
The vehicle velocity VB selected by the SH 45 is multiplied with K0 (e.g., 1.03) by a constant multiplier 51, and the product is added to the variable Kl stored in a variable memory 53 by an adder 52 to obtain the reference driving wheel velocity Vφ. Note that Kl changes in accordance with the vehicle acceleration GBF (VB′), as shown in Fig. 10. When the vehicle acceleration GBF (VB′) is large, as shown in Fig. 10, it is determined that a vehicle travels along a rough road such as a gravel road. On the gravel road, since the peak of the friction coefficient µ is present in a portion with a large slip rate in Fig. 9, Kl is increased to increase the reference driving wheel velocity Vφ as a criterion for slip determination, that is, to moderate the criterion for slip determination to increase the slip rate, thereby improving acceleration characteristics. The reference driving wheel velocity Vφ as an output from the adder 52 is subtracted from the driving wheel velocity VF calculated by the adder 25 by a subtractor 54 to calculate the slip value DV = VF - Vφ.
The slip value DV is supplied to a TSn calculating section 55 at every sampling time T in a state wherein the shift change flag CHFLG is not "1", i.e., during a period other than a period within a predetermined period of time from a shift change operation, and is integrated while being multiplied with the coefficient KI set by a KI setting section 552, thereby calculating a correction torque TSn. That is, a correction torque obtained by integrating the slip value DV, i.e., an integral correction torque TSn is calculated as follows:
TSn = KI·ΣDVi
The coefficient KI changes in accordance with the slip value DV, as shown in Fig. 11. A shift position detecting section 551 receives the shift signal SHT shown in Fig. 1A, and when the shift change operation is performed, i.e., for a predetermined period of time from when the shift signal SHT changes, the shift change flag CHFLG is set to be "1".
The slip value DV is supplied to a TPn calculating section 56 at every sampling time T, thereby calculating a correction torque TPn proportional to the slip value DV. More specifically, a correction torque proportional to the slip value DV, i.e., a proportional correction torque TPn, given by TPn = DV × Kp (Kp is the coefficient set by a Kp setting section 561) is calculated. The coefficient Kp changes in accordance with the slip value DV, as shown in Fig. 12. The coefficient Kp changes by ΔKp in accordance with the centripetal acceleration GY, as shown in Fig. 14.
The integral correction torque TSn calculated by the TSn calculating section 55 is subtracted from the reference torque Tφ by a subtractor 57. The subtraction result (TG - TSn) is input to a torque lower limit limiter 58 so that the lower limit of a torque is limited to Tb, e.g., 45 kg·m. Furthermore, TG - TSn - TPn is calculated by a subtractor 59, thus obtaining a target torque Tφ. Based on the target torque Tφ, Tφ × 1/(ρm·ρD·tr) is calculated by an engine torque calculating section 60, thereby calculating a target torque Tφ′ as an engine torque. In this case, ρM is the transmission gear ratio, ρD is the deceleration ratio, and tr is the torque ratio. The target torque Tφ′ as the engine torque calculated by the engine torque calculating section 60 is supplied to a lower limit torque limiter 61, so that the lower limit of the target torque Tφ′ is limited to 0 kg·m. After the lower limit torque of the target torque Tφ′ is limited by the lower limit torque limiter 61, the target torque Tφ′ is input to a correction section 63 through a traction control switch TRSW.
The switch TRSW is closed by a signal a outputted from the slip detector 391 when the control flag CNTl is set to be "1" and is opened when it is "0". Processing for controlling a throttle opening so that the output torque of the engine reaches the target torque is started or ended. When the switch TRSW is closed, the following three conditions (1) to (3) are satisfied at the same time: (1) the idle switch is OFF; (2) the main throttle opening ϑm falls within a hatched region of Fig. 7; (3) DVFR(FL) > 2 (km/h) and GW > 0.2g and ΔDV > 0.2g (g indicates the gravitational acceleration). When one of the following four conditions is satisfied, the switch TRSW is opened: (1) the main throttle opening ϑm < 0.533ϑs continues for 0.5 sec; (2) the ON state of the accelerator SW continues for 0.5 sec; (3) the ON state of the idle SW continues for 0.5 sec; and (4) the ABS is operated. In the correction section 63, the target torque Tφ′ is corrected in accordance with an engine cooling water temperature, an air pressure, and an intake air temperature.
The target torque Tφ′ is supplied to a Tφ′ - ϑs′ converter 64 to calculate an equivalent throttle opening ϑs′ for obtaining the target torque Tφ′ when the main throttle valve THm and the sub throttle valve THs are considered as a single unit. Note that the Tφ′ - ϑs′ relationship is shown in Fig. 13. The equivalent throttle opening ϑs′ calculated by the Tφ′ - ϑs′ converter 64 is supplied to a ϑs′ - ϑs converter 65 to obtain a sub throttle opening ϑs when the equivalent throttle opening ϑs′ and the main throttle opening ϑm are input. The sub throttle opening ϑs is output to a limiter 66. When the sub throttle opening ϑs is too small when the engine speed Ne is low, an engine stalls. Therefore, the limiter 66 provides a lower limit of the sub throttle opening ϑs set by a lower limit setting section 661. Fig. 14 shows the relationship between the lower limit and the engine speed Ne. As shown in Fig. 14, the lower limit is increased as the engine speed Ne is decreased. The sub throttle valve THs is controlled by an actuator controller 67 to obtain the sub throttle opening ϑs, so that the engine output has the target torque.
The operation of the traction control apparatus for a vehicle according to the first embodiment of the present invention with the above arrangement will now be described. The wheel velocities VFR and VFL of the driving wheels output from the wheel velocity sensors 11 and 12 are averaged by the averaging section 21 to calculate the average wheel velocity (VFR + VFL)/2. At the same time, the wheel velocities VFR and VFL of the driving wheels are supplied to the SL 22, so that a lower one of the wheel velocities VFR and VFL is selected and output. The wheel velocity output from the averaging section 21 is multiplied with the variable K by the weighting section 23, and the wheel velocity output from the SL 22 is multiplied with (1 - K) by the weighting section 24. Thereafter, the outputs from the weighting sections 23 and 24 are added to each other by the adder 25. As the variable K, a largest one of the variables KG, KT, and KV shown in Figs. 3 to 5 is selected. This is to match with various conditions of turning of a vehicle, a time after braking control is started, and the vehicle velocity VB. More specifically, when only the wheel velocity output from the SL 22 is used, engine output decreasing control is performed in accordance with the lower wheel velocity. Therefore, for a wheel having a higher wheel velocity, i.e., a wheel suffering from a larger slip value, mainly braking control is performed, and a decrease value of the engine output is made small to improve acceleration characteristics. When only the wheel velocity output from the averaging section 21, the engine output is controlled in accordance with a higher wheel velocity, i.e., a wheel velocity suffering from a larger slip value, the engine output is largely decreased, and acceleration characteristics of the vehicle are impaired. For this reason, the weighting sections 23 and 24 are arranged, so that the wheel velocities output from the SL 22 and the averaging section 21 are weighed while changing the variable K, thereby preventing slippage of the driving wheels in correspondence with the drive state of a vehicle. More specifically, when a turning tendency of a vehicle becomes large (when the centripetal acceleration GY is increased), the variable KG is set to be "1" to use the average wheel velocity of the averaging section 21, thereby preventing that a difference between rotational speeds of the left and right driving wheels caused by an inner wheel difference upon turning is erroneously determined as slippage. When a braking time is prolonged, the variable KT is set to be "1", and the lower driving wheel velocity is used to have KT = 0 for a while after traction control is started. Thus, a decrease in driving torque of a driving wheel having a larger slip value is mainly achieved by braking control, and the engine is controlled to have acceleration characteristics as the primary importance. After the time has passed and KT = 1 is established, traction control by reducing the engine output is also performed, thereby preventing an increase in energy loss due to use of braking control for a long period of time. The variable KV is set to be KV = 0 since a variation in both the driving wheels' velocity is largest upon starting of a vehicle (VB = 0) and the braking control is effective. However, in a high-speed travel state, KV = 1 so as to use only the average wheel velocity of the averaging section 21, thereby avoiding immediate braking using a brake when slippage occurs in the high-speed travel state. The wheel velocity output from the adder 25 is supplied to the differential section 26 as the driving wheel velocity VF, thereby calculating a changing value in driving wheel velocity VF as a function of time, i.e., the driving wheel acceleration GW. In addition, the wheel velocity is used for calculating the slip value DV of the driving wheels, as will be described later.
The wheel velocity VFR of the right driving wheel detected by the wheel velocity sensor 11 is supplied to the subtractor 27, so that the reference driving wheel velocity Vφ (to be described later) is subtracted therefrom. The wheel velocity VFL of the left driving wheel detected by the wheel velocity sensor 12 is supplied to the subtractor 28, so that the reference driving wheel velocity Vφ is subtracted therefrom. The output DVR from the subtractor 27 is multiplied with KB (0 < KB < 1) by the multiplier 29, and the output DVL from the subtractor 28 is multiplied with (1 - KB) by the multiplier 30. Thereafter, the outputs from the multipliers 29 and 30 are added to each other by the adder 31 so as to obtain the slip value DVFR of the right driving wheel. Similarly, the output from the subtractor 28 is multiplied with KB by the multiplier 32, and the output from the subtractor 27 is multiplied with (1 - KB) by the multiplier 33. Thereafter, the outputs from the multipliers 32 and 33 are added to each other by the adder 34 so as to obtain the slip value DVFL of the left driving wheel. For example, when a = 0.8, if one driving wheel slips, the other driving wheel is braked by a 20% force. If the brakes of the left and right driving wheels are independent of each other, when one driving wheel is braked and its rotational speed is decreased, the opposite driving wheel slips in turn upon operation of a differential gear, and is then braked. This operation is undesirably alternately repeated. The slip value DVFR of the right driving wheel is differentiated by the differential section 35 to calculate its changing value as a function of time, i.e., the slip changing value GFR. The slip value DVFL of the left driving wheel is differentiated by the differential section 36 to calculate its changing value as a function of time, i.e., the slip changing value GFL. The slip changing value GFR is supplied to the braking hydraulic pressure variation ΔP calculating section 37 to obtain the braking hydraulic pressure variation ΔP for suppressing the slip changing value GFR with reference to the GFR (GFL) - ΔP conversion map shown in Fig. 6. Similarly, the slip changing value GFL is supplied to the braking hydraulic pressure variation ΔP calculating section 38 to obtain the braking hydraulic pressure variation ΔP for suppressing the slip changing value GFL with reference to the GFR (GFL) - ΔP conversion map shown in Fig. 6.
The braking hydraulic pressure variation ΔP, output from the ΔP calculating section 37 for suppressing the slip changing value GFR is supplied to the ΔP - T converter 40 for calculating the open times T of the inlet valve 17i and the outlet valve 17o through the switch 39. The open time T of the inlet valve 17i calculated by the ΔP - T converter 40 is added to the invalid liquid amount correction value ΔTR under control by the adder 41, and the open time T of the outlet valve 17o is directly output to be used as the braking time FR of the right driving wheel. Similarly, the braking hydraulic pressure variation ΔP, output from the ΔP calculating section 38, for suppressing the slip changing value GFL is supplied to the ΔP - T converter 43 for calculating the open times T of the inlet valve 18i and the outlet valve 18o. The open time T of the inlet valve 18i is added to the invalid liquid amount correction value ΔTL under control by the adder 44, and the open time T of the outlet valve 18o is directly output to be used as the braking time FL of the left driving wheel. Then, valves 17i, 17o, 18i, 18o, 202R, 202L are controlled by the valve controllers 45, 46. As described above the open time T is corrected by being added to, the invalid liquid correction values ΔTR and ΔTL, thereby correcting a short in liquid amount from when the valves are ON until the brakes begin to function. In this manner, as has been described in the description of the arrangement, when the slip values of the driving wheels are increased and the conditions of closing the switches 39 and 42 are satisfied, the driving wheels are braked.
The wheel velocities VRR and VRL of the driven wheels detected by the wheel velocity sensors 13 and 14 are sent to the SH 45, and a higher one of the wheel velocities VRR and VRL is selected and output as the vehicle velocity VB. The SH 45 selects a higher one of inner and outer wheel velocities in consideration of an inner wheel difference when a vehicle travels along a curved road, thereby preventing erroneous determination of slippage. More specifically, as will be described later, the vehicle velocity VB serves as a reference velocity for detecting generation of slippage. The vehicle velocity VB is increased to prevent erroneous slippage determination caused by the inner wheel difference when a vehicle travels along a curved road.
At the same time, the wheel velocities VRR and VRL of the driven wheels detected by the wheel velocity sensors 13 and 14 are sent to the centripetal acceleration GY calculating section 112d of the drive state detecting means 112 so as to calculate GY as the centripetal acceleration G for judging the presence/absence and degree of turning of a vehicle.
The vehicle velocity VB selected and output by the SH 45 is input the vehicle acceleration calculating section 47 to calculate an acceleration of the vehicle velocity VB, i.e., the vehicle acceleration VB′ (GB).
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The vehicle acceleration VB′ (GB) calculated by the vehicle acceleration calculating section 47 is filtered through the filter 48 to obtain the vehicle acceleration GBF. More specifically, when a vehicle is in a state corresponding to the position "1" in Fig. 9 and the acceleration is increasing, control is quickly shifted to a state corresponding to a state of the position "2" is quickly started. Therefore, the previously calculated GBF and the presently detected GB are similarly weighted and averaged to calculate GBF = (GBF + GB)/2. Between the positions "2" and "3", in order to delay a response time and to improve acceleration characteristics such that a larger maximum torque is estimated on the basis of an acceleration closer to an acceleration corresponding to the position "2" as much as possible, the previously calculated GBF is weighted by a larger value to calculate GBF = (27GBF + 5GB)/32, thereby increasing a rate of holding the previous vehicle acceleration GBF.
The vehicle acceleration GBF is supplied to the reference torque calculating section 49 to calculate the reference torque TG = GBF × W × Re (where W is the vehicle weight and Re is the wheel radius). The reference torque TG calculated by the reference torque calculating section 49 is supplied to the torque lower limit limiter 50, so that the lower limit Ta of the reference torque TG is limited to, e.g., 45 kg·m.
The vehicle velocity VB selected by the SH 45 is multiplied with K0 (e.g., 1.03) by the constant Kl stored in the variable memory 53 by the adder 52 to obtain the reference driving wheel velocity Vφ. Note that Kl changes in accordance with the vehicle acceleration GBF (VB′), as shown in Fig. 10. When the vehicle acceleration VB′ is large, as shown in Fig. 10, it is determined that a vehicle travels along a rough road such as a gravel road. In this case, Kl is increased to increase the reference driving wheel velocity Vφ as the criterion for slip determination, that is, to moderate the criterion for slip determination to increase the slip rate, thereby improving acceleration characteristics. The reference driving wheel velocity Vφ as an output from the adder 52 is subtracted from the driving wheel velocity VF calculated by the adder 25 by the subtractor 54 to obtain the slip value DV = VF - Vφ.
The slip value DV is supplied to the TSn calculating section 55 every sampling time T in a state wherein the shift change flag CHFLG is "0", and is integrated while being multiplied with the coefficient KI, thereby calculating the correction torque TSn. That is, slip values DVi at the corresponding sampling times when the shift change flag CHFLG is "0" are integrated to obtain a correction torque, i.e., the integral correction torque TSn:
TSn = KI·ΣVi
The coefficient KI changes in accordance with the slip value DV, as shown in Fig. 11. In this manner, only when the shift change flag CHFLG is "0", the TSn calculating section 32 calculates the slip value DV. Therefore, the calculation of the slip value DV performed by the TSn calculating section 32 is held for a predetermined period of time after a shift change operation is performed. For this reason, slippage of the driving wheels caused by a shift change shock is prevented from being erroneously detected as acceleration slippage.
The slip value DV is supplied to the TPn calculating section 56 every sampling time T, thereby calculating the correction torque TPn proportional to the slip value DV. More specifically, the correction torque proportional to the slip value DV, i.e., the proportional correction torque TPn, given by TPn = DV × Kp (Kp is the coefficient set by the Kp setting section 56) is calculated. The coefficient Kp changes in accordance with the slip value DV, as shown in Fig. 12.
More specifically, as shown in Figs. 11 and 12, when DV > -1, the coefficients KI and Kp are smaller than those when DV < -1. A region larger than Vφ in Fig. 8 almost corresponds to DV > -1. In this region, since a variation range is wide, if the coefficients KI and Kp are large, a gain is increased although a change in slip value DV is large and control becomes unstable. When DV < -1 (that is, an almost hatched region in Fig. 8), the coefficients KI and Kp are increased to increase the gain. When DV < -1, a variation range is present only between Vφ and VB and is narrow, as shown in Fig. 8, the coefficients KI and Kp are increased to increase the gain, thereby shortening a response time. When the centripetal acceleration GY is increased, i.e., a turning tendency becomes large, as shown in Fig. 15, ΔKp (Fig. 12) is increased to increase the value Kp when DV > -1. Thus, the gain is increased not to cause unstable control, thereby suppressing generation of slippage along a curved road and improving turning performance.
The integral correction torque TSn calculated by the TSn calculating section 55 is subtracted from the reference torque Tφ by the subtractor 57. The subtraction result (TG - TSn) is input to the torque lower limit limiter 58 so that the lower limit of a torque is limited to Tb, e.g., 45 kg·m. Furthermore, TG - TSn - TPn is calculated by the subtractor 59, thus obtaining the target torque Tφ. Based on the target torque Tφ, Tφ × 1/(ρM·ρD·tr) is calculated by the engine torque calculating section 60, thereby calculating the target torque Tφ′ as an engine torque. In this case, ρM is the transmission gear ratio, ϑD is the deceleration ratio, and tr is the torque ratio. A torque exceeding 0 kg·m is output to the correction section 63 as the target torque Tφ′ through the switch TRSW. In the correction section 63, the target torque Tφ′ is corrected in accordance with an engine cooling water temperature, an air pressure, and an intake air temperature.
The target torque Tφ′ is supplied to the Tφ′ - ϑs′ converter 64 to calculate the equivalent throttle opening ϑs′ for obtaining the target torque Tφ′ when the main throttle valve THm and the sub throttle valve THs are considered as a single unit. Note that the Tφ′ - ϑs′ relationship is shown in Fig. 13. The equivalent throttle opening ϑs, calculated by the Tφ′ - ϑs′ converter 64 is supplied to the ϑs′ - ϑs converter 65 to obtain the sub throttle opening ϑs when the equivalent throttle opening ϑs′ and the main throttle opening ϑm are input. The sub throttle opening ϑs is output to the limiter 66. When the sub throttle opening ϑs is too small when the engine speed Ne is low, an engine tends to stall. The lower limit of the sub throttle opening ϑs is set so as to be increased as the engine speed Ne is lower. The sub throttle valve is controlled to obtain the sub throttle opening ϑs, so that the engine output torque has a maximum torque capable of being transmitted in a present road surface state.
When only one throttle valve is used unlike in the first embodiment wherein two throttle valves are used, the equivalent throttle opening ϑs′ is directly used as the opening of the throttle valve.
In the first embodiment, the vehicle velocity VB is multiplied with K0 by the constant multiplier 51, and the product is added to the variable Kl stored in the variable memory 53 by the adder 52 to obtain the reference driving wheel velocity Vφ. However, the present invention is not limited to this. For example, after the vehicle velocity VB is multiplied with a variable, the product can be added to a constant to calculate the reference driving wheel velocity Vφ. Alternatively, the vehicle velocity VB may be multiplied with a variable to obtain the reference driving wheel velocity Vφ.
A second embodiment of the present invention will now be described with reference to Figs. 17A to 36. The same reference numerals in Fig. 17A denote the same parts as in Fig. 1A, and a detailed description thereof will be omitted. In the second embodiment, as shown in Fig. 16, a main throttle valve THm whose opening ϑm is controlled in accordance with an operation amount of an accelerator pedal and a sub throttle valve THs whose opening is controlled by a traction controller 15 are arranged in series with each other.
The traction controller 15 receives a shift signal SHT from a transmission controller 151 for controlling switching of shift positions of an automatic transmission 16m. The SHT signal indicates a shift position of the automatic transmission 16m. The traction controller 15 also receives an engine speed signal Ne of the engine and the opening signal ϑm of the main throttle valve THm shown in Fig. 16.
The detailed arrangement of the traction controller 15 shown in Fig. 17A will now be described with reference to Fig. 17B. The traction controller 15 comprises an MPU (micro processor unit) 15p including various registers, an ALU (arithmetic and logic unit), and the like, a memory 15m storing a traction control program, various maps, coefficient data, variable data, counters, and flags, and the like.
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More specifically, the memory 15m stores the traction control program whose control content is shown in Figs. 18A to 18C in units of functional blocks, a variable KG shown in Fig. 19, a variable Kr shown in Fig. 20, a slip value Vg shown in Fig. 21, a slip value Vd shown in Fig. 22, a coefficient KV shown in Figs. 23 to 28, a coefficient KB shown in Fig. 29, a GFR (GPL) - ΔP map shown in Fig. 30, a target torque lower limit Tlim shown in Figs. 32 and 33, a vehicle weight W and a radius of tire Re, correction torques TSn and TPn, a target torque Tφ, a braking time FR of the right driving wheel, a braking time FL of the left driving wheel, a present vehicle acceleration GB, an immediately preceding vehicle acceleration GB, a present vehicle acceleration GBF passed through a filter, an immediately preceding vehicle acceleration GBF passed through the filter, coefficients GKI and GKp whose values are changed in accordance with gear shift positions, a timer t1 for counting a time after traction control is started, a timer t2 for counting a setting time t2 after a shift change operation is started, a control flag CNTl which is set when a start condition for starting engine output control is established and is reset when an end condition for ending the control is established, and the like.
The detailed arrangement of the traction controller 15 will be described below with reference to the block diagrams of Figs. 18A to 18C showing the control of the traction controller 15 in units of functional blocks. Wheel velocities VFR and VFL of the driving wheels detected by wheel velocity sensors 11 and 12 are sent to a high vehicle velocity selecting section (SH) 71, so that a higher one of the wheel velocities VFR and VFL is selected and output. The wheel velocities VFR and VFL of the driving wheels detected by the wheel velocity sensors 11 and 12 are averaged by an averaging section 72 to calculate an average wheel velocity (VFR + VFL)/2. The selected wheel velocity output from the SH 71 is multiplied with the variable KG by a weighting section 73. The average wheel velocity output from the averaging section 72 is multiplied with (1 - KG) by a weighting section 74. The outputs from the weighting sections 73 and 74 are added to each other by an adder 75. Note that the variable KG is set by KG setting section 731 and changes in accordance with a centripetal acceleration GY as shown in Fig. 19. As shown in Fig. 19, the variable KG is proportional to the centripetal acceleration until the centripetal acceleration GY is a predetermined value (e.g., 0.1g: g is the gravitational acceleration), and is set to be "1" when it exceeds the predetermined value.
Wheel velocities of driven wheels detected by wheel velocity sensors 13 and 14 are input to a low vehicle velocity selecting section (SL) 76, so that a smaller wheel velocity is selected. Furthermore, the wheel velocities of the driven wheels detected by the wheel velocity sensors 13 and 14 are input to a high vehicle velocity selecting section (SH) 77, so that a higher wheel velocity is selected. The lower wheel velocity selected by the SL 76 is multiplied with a variable Kr by a weighting section 78, and the larger wheel velocity selected by the SH 77 is multiplied with a variable (1 - Kr) by a weighting section 79. The variable Kr is set by a Kr settign section 781 and changes between "1" and "0" in accordance with the centripetal acceleration GY, as shown in Fig. 20.
The wheel velocities output from the weighting sections 78 and 79 are added to each other by an adder 80 to obtain a driven wheel velocity VR. The driven wheel velocity VR is multiplied with (1 + α) by a multiplier 801 to obtain a target driving wheel velocity Vφ.
The target driving wheel velocity Vφ output from the multiplier 801 is subtracted from the driving wheel velocity VF output from the adder 75 by a subtractor 81 to calculate a slip value DVi′ (= VF - Vφ). The slip value DVi′ is corrected by an adder 82 in accordance with the centripetal acceleration GY and a changing value ΔGY of the centripetal acceleration GY as a function time. The changing value ΔGY of the centripetal acceleration GY is calculated at ΔGY calculating section 841. More of specifically, the slip correction value Vg which changes in accordance with the centripetal acceleration GY shown in Fig. 21 is set in a slip value correction section 83, and the slip correction value Vd which changes in accordance with the changing value ΔGY of the centripetal acceleration GY as shown in Fig. 22 is set in a slip value correction section 84. The slip correction values Vd and Vg are added to the slip value DVi′ output from the subtractor 81 by the adder 82 to obtain a slip value DVi.
The slip value DVi is supplied to a calculating unit 85a in a TSn calculating section 85 every 15-ms sampling time T. The slip values DVi are integrated while being multiplied with a coefficient KI, thereby calculating a correction torque TSn′. That is, a correction torque obtained by integrating the slip values DVi, i.e., an integral correction torque TSn′ is calculated as follows:
TSn′ = ΣKI·DVi
(KI is the coefficient which changes in accordance with the slip value DVi)
The integral correction torque TSn′ is a correction value for a torque driving the driving wheels WFR and WFL, and a control gain must be adjusted in accordance with a change in characteristics of a power transmission mechanism between an engine 16 and the driving wheels upon switching of a shift position. Therefore, the correction torque TSn′ is respectively multiplied with coefficients GKi according to a shift position detected by a shift position detecting section 861, thereby calculating the integral correction torque TSn which is corrected in accordance with the shift position.
The slip value DVi is supplied to a calculating unit 86a of a TPn calculating section 86 every sampling time T so as to calculate a correction torque Tpn′ proportional to the slip value DVi. That is, a correction torque proportional to the slip value DVi, i.e., a proportional correction torque Tpn′ is calculated as follows:
TPn′ = DVi·Kp
(Kp is the coefficient which changes in accordance with the slip value DVi)
The proportional correction torques TPn′ are respectively multiplied with different coefficients GKp according to a shift position detected by a shift position detecting section 861 for the same reason as the integral correction torque TSn′, thus obtaining a proportional correction torque TPn which is corrected according to the shift position.
When a shift-up operation is detected on the basis of the shift signal SHT input to the traction controller 15, the coefficients GKi and GKp are switched to those after shift change operation after the setting time t2 has been measured by the timer t2 after detection. When a shift-down operation is detected on the basis of the shift signal SHT, the coefficients GKi and GKp are immediately switched.
The driven wheel velocity VR output from the adder 80 is input to a reference torque calculating section 87 as a vehicle velocity VB. In a vehicle acceleration calculating unit 87a of the reference torque calculating section 87, an acceleration VB′ (GB) of the vehicle velocity is calculated.
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The vehicle acceleration VB′ (GB) calculated by the vehicle acceleration calculating unit 87a is filtered through a filter 87b to obtain a vehicle acceleration GBF. In the filter 87b, when a slip rate S shown in Fig. 31 is in a state corresponding to a position "1" and when an acceleration is increased, control is quickly shifted to a state corresponding to a position "2". Therefore, GBF as an immediately preceding output of the filter 87b and presently detected GB are similarly weighted and averaged:
GBF = (GB + GBF)/2 (1a)
When the slip rate S > S1 (S1 is set to be a value slightly smaller than a slip rate Smax yielding a maximum coefficient friction coefficient µ) and an acceleration is decreased, e.g., when the slip rate S is shifted from the position "2" to a position "3", the filter 87b is switched to a slower filter. That is,
GBF = (GB + 7GBF)/8 (2a)
In this equation, the immediately preceding output GBF of the filter 87b is weighted by a larger value.
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When the slip rate S ≦ S1 and an acceleration is decreased, i.e., when an acceleration is decreased in a region "1", control according to a state of Smax should be held as much as possible, the filter 87b is switched to a further slower filter. That is,
GBF = (GB + 15GBF)/16 (3)
The immediately preceding output GBF of the filter 87b is weighted by a much larger value. In this manner, the filter 87b is switched in three ways as shown in equations (1a), (2a), and (3) in accordance with the slip rate and an acceleration state. The vehicle acceleration GBF is supplied to a reference torque calculating unit 87c to calculate a reference torque TG given by:
TG = GBF × W × Re
where W is the vehicle weight and Re is the wheel radius.
The integral correction value TSn is subtracted from the reference torque TG by a subtractor 88, and the proportional correction torque TPn is subtracted from the output from the subtractor 88 by a subtractor 89. In this manner, the target torque Tφ is calculated by Tφ = TG - TSn - TPn.
Since the target torque Tφ indicates a torque for driving the driving wheels WFR and WFL, it is divided by a total gear ratio between the engine 16 and the driving wheels to be converted to a target engine torque. A lower limit setting section 911 provides the lower limit Tlim of an engine torque to a limiter 91, the lower limit of a target engine torque Tφ′ is limited by the lower limit Tlim which changes in accordance with a lapse of time from the beginning of traction control or the vehicle velocity VB as shown in Fig. 32 or 33. The target engine torque Tφ′ whose lower limit is limited by the limiter 91 is supplied to a torque/throttle opening converter 92, thereby obtaining an opening ϑs of the sub throttle valve for generating the target engine torque Tφ′. The sub throttle valve THs is controlled by an actuator controller 67 so that the engine output torque has the target engine torque Tφ′.
The wheel velocities VRR and VRL of the driven wheels are supplied to a centripetal acceleration calculating section 112e of the drive state detecting section 112 to obtain a centripetal acceleration GY′ to judge a degree of turning. The centripetal acceleration GY′ is supplied to a centripetal acceleration correction section 112f, and is corrected in accordance with the vehicle velocity detected by a detector 1.
More specifically, GY = KV·GY′ is calculated. The coefficient KV changes in accordance with the vehicle velocity as shown in Figs. 23 to 28, so that the centripetal acceleration GY is corrected in accordance with the vehicle velocity.
A larger driven wheel velocity output from the SH 77 is subtracted from the driving wheel velocity VFR by a subtractor 95. Furthermore, the larger driven wheel velocity output from the SH 77 is subtracted from the the driving wheel velocity VFL by a subtractor 96.
The output from the subtractor 95 is multiplied with KB (0 < KB < 1) by a multiplier 97, and the output from the subtractor 96 is multiplied with (1 - KB) by a multiplier 98. Thereafter, the outputs from the multipliers 97 and 98 are added to each other by an adder 99 to obtain a slip value DVFR for the right driving wheel. Similarly, the output from the subtractor 96 is multiplied with KB by a multiplier 100, and the output from the subtractor 95 is multiplied with (1 - KB) by a multiplier 101. Thereafter, the outputs from the subtractors 100 and 101 are added to each other by an adder 102 to obtain a slip value DVFL for the left driving wheel. The variable KB is set by a KB setting section 971 and its changes in accordance with a lapse of time from start of traction control, as shown in Fig. 29. Upon start of traction control, the variable KB is set to be "0.5", and approaches "0.8" as the traction control progresses. For example, when KB = 0.8, if one driving wheel slips, it is recognized that the other driving wheel slips by a value 20% of one driving wheel, and braking control is performed accordingly. If the brakes of the left and right driving wheels are independent of each other, when one driving wheel is braked and its rotational speed is decreased, the opposite driving wheel slips in turn upon operation of a differential gear, and is then braked. This operation is undesirably alternately repeated. The slip value DVFR of the right driving wheel is differentiated by a differential section 103 to calculate its changing value as a function of time, i.e., a slip changing value GFR. The slip value DVFL of the left driving wheel is differentiated by a differential section 104 to calculate its changing value as a function of time, i.e., a slip changing value GFL. The slip changing value GFR is supplied to a braking hydraulic pressure variation ΔP calculating section 105 to obtain a braking hydraulic pressure variation ΔP for suppressing the slip changing value GFR with reference to a GFR (GFL) - ΔP conversion map shown in Fig. 30. Similarly, the slip changing value GFL is supplied to a braking hydraulic pressure variation ΔP calculating section 106 to obtain a braking hydraulic pressure variation ΔP for suppressing the slip changing value GFL with reference to the GFR (GFL) - ΔP conversion map shown in Fig. 30.
The braking hydraulic pressure variation ΔP, output from the ΔP calculating section 105 for suppressing the slip changing value GFR is supplied to a ΔP - T converter 107 for calculating open times T of an inlet valve 17i and an outlet valve 17o through a switch BSW. When the variation ΔP is a positive value, the open time of the inlet valve 17i is calculated, and when the variation ΔP is a negative value, the open time of the outlet valve 17o is calculated. The calculated open time is used as a braking time FR for the right driving wheel.
107a is a right drive time accumulating section. This section 107a calculates an accumulation value ΣTir of drive times of the right inlet valve 17i set every predetermined period from the signal b is outputted until an immediately preceding period, and an accumulation value ΣTor of drive times of the right outlet valve 17o set every predetermined period. The accumulation values ΣTir and ΣTor are sent to a right drive time correcting section 107b. the section 107b calculates an invalid liquid amount correction value ΔTR (= KT·ΣTor - ΣTir), KT is constant. Thereafter, the open time T of the inlet valve 17i calculated by the ΔP - T converter 107 is added to the invalid liquid amount correction value ΔTR in control by an adder 107c, and the open time T of the outlet valve 17o is directly output to be used as the breaking time FR of the right driving wheel WFR. Then, the driving time of the inlet valve 17i and the outlet valve 17o is controlled by a valve controller 107d.
The braking hydraulic pressure variation ΔP, output from the ΔP calculating section 10b for suppressing the slip changing value GFL is supplied to a ΔP - T converter 108 for calculating open times T of the inlet valve 18i and the outlet value 18o through a switch BSW.
108a is a left drive time accumulating section. This section 108a calculates an accumulation value ΣTiℓ of drive times of the right inlet valve 18i set every predetermined period from the signal b is outputted until an immediately preceding period, and an accumulation value ΣTor of drive times of the right outlet valve 18o set every predetermined period. The accumulation values ΣTiℓ and ΣToℓ are sent to a left drive time correcting section 108b. the section 108b calculates an in valid liquid amount correction value ΔTR (= KT·ΣToℓ - ΣTiℓ), KT is constant. Thereafter, the open time T of the inlet valve 18i calculated by the ΔP - T converter 108 is added to the invalid liquid amount correction value ΔTL in control by an adder 108c, and the open time T of the outlet valve 18o is directly output to be used as the breaking time FL of the left driving wheel WFL. Then, the driving time of the inlet valve 18i and the outlet valve 18o is controlled by a valve controller 108d.
The correction value corrects a delay time from when a brake liquid amount is increased until a brake begins to function. In this case, ΔTR(L) can be maximum of 40 ms to correct delay time, it is clipped at 40 ms.
a
In Fig. 30, when braking is performed during turning, the variation ΔP in the inner wheel side detected by the inner wheel detecting section 112h during turning is as indicated by a broken line in order to increase a braking force of the inner driving wheel.
The operation of the traction control apparatus for a vehicle according to the second embodiment of the present invention will now be described. In Fig. 17A and Figs. 18A and 18C, the wheel velocities of the driven wheels (rear wheels) output from wheel velocity sensors 13 and 14 are input to the SH 77, the SL 76, and the centripetal acceleration calculating section 93. The SL 76 selects a lower one of the wheel velocities of the left and right driven wheels. The SH 77 selects a higher one of the wheel velocities of the left and right driven wheels. In a normal straight travel state, if the wheel velocities of the left and right driven wheels are equal to each other, the same wheel velocity is selected and output from the SL 76 and the SH 77. The centripetal acceleration calculating section 93 receives the wheel velocities of the left and right driven wheels, and calculates a degree of turning on the basis of the wheel velocities of the left and right driven wheels, i.e., a degree indicating immediate turning.
The way of calculating the centripetal acceleration in the centripetal acceleration calculating section 93 will be described below. In a front-wheel drive vehicle, since the rear wheels are driven wheels, a vehicle velocity at that position can be detected by wheel velocity sensors regardless of slippage by driving, an Ackerman geometry can be utilized. In a normal turning state, a centripetal acceleration GY′ is given by:
GY′ = v²/r (4)
(v = vehicle velocity, r = turning radius)
For example, when the vehicle turns to the right, as shown in Fig. 35, if the center of turn is represented by M0, a distance from the center M0 of turn to an inner wheel (WRR) is represented by r1, a tread is represented by Δr, a wheel velocity of the inner wheel (WRR) is represented by v1, and a wheel velocity of an outer wheel is represented by v2, the following relation is established:
v2/vl = (Δr + r1)/rl (5)
Equation (5) can be modified as follows:
l/r1 = (v2 - v1)/(Δr.vl) (6)
The centripetal acceleration GY′ with reference to the inner wheel is given by:
GY′ = vl²/rl
= vl²·(v2 - v1)/(Δr·vl)
= vl·(v2 - v1)/Δr (7)
The centripetal acceleration GY′ can be calculated by equation (7). During turning, since the wheel velocity v1 of the inner wheel is lower than the wheel velocity v2 of the outer wheel, the centripetal acceleration GY′ is calculated using the wheel velocity v1 of the inner wheel, and the centripetal acceleration GY′ is calculated to be smaller than an actual one. Therefore, the coefficient KG multiplied in the weighting section 73 becomes a smaller value as the centripetal acceleration GY′ is estimated smaller. Since the driving wheel velocity VF is estimated smaller, the slip value DV′ (VF - Vφ) is also estimated smaller. Thus, the target engine torque is estimated larger to provide a sufficient drive force during turning.
r
When a vehicle travels at a very low velocity, the distance between the inner wheel and the center M0 of turn is r1. However, in a vehicle which tends to be understeered as a velocity is increased, the center of turn is shifted to M, and its distance becomes (r > r1). When the velocity is increased in this manner, since the radius of turn is calculated as r1, the centripetal acceleration GY′ calculated on the basis of equation (7) becomes larger than an actual one. For this reason, the centripetal acceleration GY′ calculated by the centripetal acceleration calculating section 112e is supplied to the centripetal acceleration correction section 112f, and is multiplied with the coefficient KV shown in Fig. 23 so that the centripetal acceleration GY′ is decreased at a high velocity. The variable KV is set to be smaller as the vehicle velocity is increased, and may be set, as shown in Fig. 24 or 25. In this manner, the centripetal acceleration correction section 112f outputs the corrected centripetal acceleration GY as the centripetal acceleration GY′ as the contripetal acceleration GY.
In a vehicle which tends to be oversteered (r < r1) as a vehicle velocity is increased, correction opposite to that for the vehicle which tends to be understeered is performed by the centripetal acceleration correction section 94. That is, one of the variables KV shown in Figs. 26 to 28 is used, and the centripetal acceleration GY′ calculated by the centripetal acceleration calculating section 93 is corrected to be increased as the vehicle velocity is increased.
The lower wheel velocity selected by the SL 76 is multiplied with the variable Kr shown in Fig. 20 by the weighting section 78, and the higher wheel velocity selected by the SH 77 is multiplied with the variable (1 - Kr) by the weighting section 79. The variable Kr is set to be "1" during turning wherein the centripetal acceleration GY becomes larger than 0.9g, and is set to be "0" when the centripetal acceleration GY becomes smaller than 0.4g.
Therefore, during turning wherein the centripetal acceleration GY becomes larger than 0.9g, the lower driven wheel velocity output from the SL 76, i.e., the wheel velocity of the inner wheel upon steering is selected. The wheel velocities output from the weighting sections 78 and 79 are added to each other by the adder 80 to obtain the driven wheel velocity VR. The driven wheel velocity VR is multiplied with (1 + α) by the multiplier 801 to obtain the target driving wheel velocity Vφ.
After the higher one of the driving wheel velocities is selected by the SH 71, it is multiplied with the variable KG shown in Fig. 19 by the weighting section 73. Furthermore, the average vehicle velocity (VFR + VFL)/2 of the driving wheels calculated by the averaging section 72 is multiplied with (1 - KG) by the weighting section 74, and is added to the output from the weighting section 73 by the adder 75 to obtain the driving wheel velocity VF. Therefore, if the centripetal acceleration GY exceeds 0.1g, since KG = 1, a higher one of the two driving wheel velocities output from the SH 71 is output. More specifically, if the degree of turning of the vehicle is increased and the centripetal acceleration GY exceeds 0.9g, since KG = Kr = 1, an outer driving wheel velocity as a higher wheel velocity is set to be the driving wheel velocity VF, and an inner driven wheel velocity as a lower wheel velocity is set to be the driven wheel velocity VR. The slip value DVi′ calculated by the subtractor 81 is given by VF - Vφ, the slip value DVi′ is estimated larger. Therefore, since the target torque Tφ is estimated smaller, the engine output is reduced, and the slip rate S is decreased to increase a lateral force A, as shown in Fig. 34. Therefore, a gripping force of the wheels during turning can be increased, thus guaranteeing safe turning.
The slip value DV′ is added with the slip correction value Vg shown in Fig. 21 by the slip value correction section 83 and added with the slip value Vd shown in Fig. 22 by the slip value correction section 84 only when the vehicle turns while the centripetal acceleration GY is generated. For example, assuming a 90° turn, the centripetal acceleration GY and its changing value ΔGY are positive values in the first half of turning. However, in the second half of turning, the changing value ΔGY of the centripetal acceleration GY becomes a negative value. Therefore, in the first half of turning, the slip value DVi′ is added to the slip correction value Vg (> 0) shown in Fig. 21 and the slip correction value Vd (> 0) shown in Fig. 22 by the adder 82 to obtain the slip value DVi. In the second half of turning, the slip correction value Vg (> 0) and the slip correction value Vd (< 0) are added to the slip value DVi′ to obtain the slip value DVi. The slip value DVi in the second half of turning can be estimated to be smaller than that in the first half of turning. In the first half of turning, the engine output is decreased to increase a lateral force to improve turning characteristics. In the second half of turning, the engine output is recovered relative to the first half to improve acceleration characteristics after turning is terminated.
The corrected slip value DVi is supplied to the TSn calculating section 85 every 15-ms sampling time T. In the TSn calculating section 85, the slip values DVi are integrated while being multiplied with the coefficient KI, thereby obtaining the correction torque TSn. That is,
TSn = GKi·ΣKI·DVi
(KI is the coefficient which changes in accordance with the slip value DVi)
In this manner, a correction torque obtained by integrating the slip values DVi, i.e., the integral correction torque TSn can be obtained.
The slip value DVi is supplied to the TPn calculating section 86 every sampling time T, thus calculating the correction torque TPn. That is,
TPn = GKp·DVi·Kp
(Kp is the coefficient which changes in accordance with the slip value DVi)
Thus, a correction torque proportional to the slip value DVi, i.e., the proportional correction torque TPn is calculated.
The values of the coefficients GKi and GKp used in calculations of the coefficient multipliers 85b and 86b are switched to values corresponding to a shift position after a shift change operation after the set time t2 has passed from the beginning of the shift change operation in a shift-up mode. A given time is required from beginning of the shift change operation until the shift position is actually switched and the shift change operation is completed. In the shift-up mode, if the coefficients GKi and GKp corresponding to the higher shift position after the shift change operation are used immediately after the shift change operation is started, the values of the correction torques TSn and TPn become values corresponding to the higher shift position. Therefore, the correction torques become smaller than those before the shift change operation is started although an actual shift change operation is not completed, and hence, the target torque Tφ is increased. Thus, slippage is induced, resulting in unstable control.
The driven wheel velocity VR output from the adder 80 is input to the reference torque calculating section 87 as the vehicle velocity VB. The vehicle acceleration calculation unit 87a then calculates the acceleration VB′ (GB) of the vehicle. The acceleration GB of the vehicle calculated by the vehicle acceleration calculating unit 87a is filtered according to one of equations (1) to (3) by the filter 87b, as has been described in the description of the arrangement of the filter 87b, so that GBF is optimally held in accordance with the state of the acceleration GB. In the reference torque calculating unit 87c, the reference torque TG (= GBF × W × Re) is calculated.
The integral correction torque TSn is subtracted from the reference torque TG by the subtractor 88 and the proportional correction torque TPn is subtracted from the reference torque TG from the subtractor 88 by the subtractor 89. In this manner, the target torque Tφ is calculated by Tφ = TG - TSn - T pn.
The target torque Tφ is converted to the target engine torque Tφ′ by the engine torque calculating section 90. In the lower limit setting section 91 which provides the lower limit Tlim of the engine torque, the lower limit of the target engine torque Tφ′ is limited by the lower limit Tlim which changes in accordance with the lapse of time from start of traction control or the vehicle velocity VB, as shown in Fig. 32 or 33. More specifically, at the beginning of traction control or when the reference torque TG fails to detect at a low velocity, the value of the torque lower limit Tlim is set to be slightly larger as shown in Fig. 32 or 33, and the engine torque Tφ′ exceeding a torque causing no slippage can be output, thus assuring good acceleration characteristics. When the engine torque Tφ′ exceeding a torque causing no slippage is output and slippage occurs, generation of slippage is suppressed by braking control.
The target engine torque Tφ whose lower limit is limited by the limiter 91 is supplied to the torque/throttle opening converter 92, and the opening ϑs of the sub throttle valve for generating the target engine torque Tφ′ is obtained. An opening ϑs of the sub throttle valve is adjusted by the actuator controller 67, so that the engine output torque has the target engine torque Tφ′.
The larger driven wheel velocity output from the SH 87 is subtracted from the driving wheel velocity VFR by the subtractor 95. Furthermore, the higher driven wheel velocity output from the SH 87 is subtracted from the driving wheel velocity VFL by the subtractor 96. Therefore, the outputs from the subtractors 95 and 96 are estimated smaller. Even when a difference between left and right driven wheel velocities is generated by an inner wheel difference during turning, a braking operation due to an erroneous detection of slippage can be prevented, thus improving travel stability.
The output from the subtractor 95 is multiplied with KB (0 < KB < 1) by the multiplier 97, and the output from the subtractor 96 is multiplied with (1 -KB) by the multiplier 98. Thereafter, the outputs from the multipliers 97 and 98 are added to each other by the adder 99 to obtain the slip value DVFR of the right driving wheel. At the same time, the output from the subtractor 96 is multiplied with KB by the multiplier 100, and the output from the subtractor 95 is multiplied with (1 - KB) by the multiplier 101. Thereafter, the outputs from the multipliers 100 and 101 are added to each other by the adder 102 to obtain the slip value DVFL of the left driving wheel. As shown in Fig. 29, the variable KB changes in accordance with a lapse of time from the beginning of traction control. The variable KB is set to be "0.5" at the beginning of the traction control, and approaches "0.8" as the traction control progresses. More specifically, when slippage of the driving wheels is eliminated by braking, both the wheels are braked at the same time at the beginning of braking, so that an uncomfortable steering shock at the beginning of braking on, e.g., a split road can be eliminated. An operation when the braking control continues and KB becomes "0.8" will be described below. In this case, if one driving wheel slips, it is recognized that the other driving wheel also slips by a value 20% of one driving wheel, and braking control is performed accordingly. If the brakes of the left and right driving wheels are independent of each other, when one driving wheel is braked and its rotational speed is decreased, all the driving torque is transmitted to the opposite driving wheel, and the opposite driving wheel slips in turn upon operation of a differential gear and is then braked. This operation is undesirably alternately repeated. The slip value DVFR of the right driving wheel is differentiated by the differential section 103 to calculate its changing value as a function of time, i.e., the slip changing value GFR. The slip value DVFL of the left driving wheel is differentiated by the differential section 104 to calculate its changing value as a function of time, i.e., the slip changing value GFL. The slip changing value GFR is supplied to the braking hydraulic pressure variation ΔP calculating section 105 to obtain the braking hydraulic pressure variation ΔP for suppressing the slip changing value GFR with reference to the GFR (GFL) - ΔP conversion map shown in Fig. 30. Similarly, the slip changing value GFL is supplied to the braking hydraulic pressure variation ΔP calculating section 106 to obtain the braking hydraulic pressure variation ΔP for suppressing the slip changing value GFL with reference to the GFR (GFL) - ΔP conversion map shown in Fig. 30.
The braking hydraulic pressure variation ΔP, output from the ΔP calculating section 105 for suppressing the slip changing value GFR is supplied to the ΔP - T converter 107, and the open time of the inlet valve 17i or the open time of the outlet valve 17o is calculated. The calculated open time is used as the braking time FR for the right driving wheel, and the left driving wheel WFR is braked. Similarly, the braking hydraulic pressure variation ΔP, output from the ΔP calculating section 106, for suppressing the slip changing value GFL is supplied to the ΔP - T converter 108, and the open time of the inlet valve 18i or the open time of the outlet valve 18o is calculated. The calculated open time is used as the braking time FL for the left driving wheel, and the left driving wheel WFL is braked. Then, valves 17i, 17o, 18i, 18o, 202R, 202L are controlled by the valve controllers 107d, 108d.
a
In Fig. 30, when braking is performed during turning, the variation ΔP of the inner wheel side during turning is as indicated by a broken line in order to enhance braking of the inner driving wheel. During turning, the inner wheel tends to slip since a load is shifted toward the outer wheel side. This can be prevented such that the braking hydraulic pressure variation ΔP of the inner wheel is increased to be larger than that of the outer wheel.
In the second embodiment, the coefficients GKi and GKp used in calculations by the coefficient multipliers 85b and 86b are switched to values according to a shift position upon completion of the shift change operation after the lapse of a setting time from the beginning of the shift change operation in a shift-up mode. Switching in the shift-up mode may be performed upon completion of the shift change operation, and switching in a shift-down mode may be performed at the beginning of the shift change operation. In this manner, the target engine torque Tφ′ in the shift-up or shift-down mode is suppressed to prevent induction of slippage.
n
n
n-1
n
n
n-1
In the filter 87b, when the slip rate S ≦ S1 and the acceleration is decreased, the filter of equation (3) is selected. The vehicle acceleration GB may be held without using the filter of equation (3). The filter of equation (1) is used when the acceleration is increased. At a very low vehicle velocity (VB < 3 km/h), a slow filter may be defined as:
GBF = (GB + 3GBF)/4
At a normal vehicle velocity (VB > 3 km/h), a fast filter may be defined as:
GBF = (GB + GBF)/2
In the lower limit setting section 91, when the degree of turning is increased, i.e., when the centripetal acceleration GY is increased, the lower limit Tlim may be decreased. That is,
Tlim = Tlim - α·GY (≧ 0)
(α is the coefficient)
Thus, generation of any slippage during turning is prevented, and a large lateral force is maintained. A vehicle can be prevented from being deviated due to small slippage during turning.
In the second embodiment, the calculation of the centripetal acceleration GY′ in the centripetal acceleration calculating section 93 is made with reference to the inner wheel velocity v1. However, the present invention is not limited to this. For example, the calculation may be made with reference to an average of the inner and outer wheel velocities v1 and v2 or with reference to the outer wheel velocity v2.
For example, a case will be described below wherein the centripetal acceleration GY′ is calculated with reference to an average value of the inner and outer wheel velocities v1 and v2. In this case, when v = v2 + v1/2 and r = (r1 + Δr)/2 are substituted in equation (4) and equation (4) is modified using equation (5), the centripetal acceleration GY′ is expressed by:
GY′ = (v2² - vl²)/2·Δr (8)
On the other hand, when the calculation is made with reference to the outer wheel velocity v2, if v = v2 and r = r1 + Δr are substituted in equation (4) and equation (4) is modified using equation (5), the centripetal acceleration GY′ is expressed by:
GY′ = (v2 - vl)v2/Δr (9)
Therefore, when the centripetal acceleration GY′ is calculated with reference to the outer wheel velocity v2, it is estimated higher than an actual one, and hence, the slip value DV′ is also estimated larger than an actual one. Therefore, the target torque Tφ is estimated smaller, and the engine output torque is reduced than required, thus increasing a lateral force and improving turning characteristics. When the centripetal acceleration GY′ is calculated with reference to the average value of the inner and outer wheel velocities v1 and v2, intermediate engine output control between a case using the inner wheel velocity v1 and a case using the outer wheel velocity v2 is made. Therefore, the driving force and turning characteristics during turning are equally emphasized.
A traction control apparatus according to a third embodiment of the present invention will now be described with reference to Figs. 36 to 39. The third embodiment corresponds to a modification of the second embodiment described above with reference to Figs. 17A to 36. That is, the third embodiment is substantially the same as the second embodiment except that the diagram shown in Fig. 36 is used in place of that shown in Fig. 17A and the drive state detecting section 112 of Fig. 39 is used in place of the shown in Fig. 18A. Fig. 37 shows the principle of a lateral G sensor 111 (112i) shown in Fig. 36, and Fig. 38 shows output voltage characteristics of the lateral G sensor 111.
The same reference numerals in Fig. 36 denote the same parts as in Fig. 17A, and a detailed description thereof will be omitted. In Fig. 36, reference numeral 110 (112k) denotes a steering angle sensor for detecting a steering speed of a steering wheel; and 111 (112i), a lateral G sensor for detecting a lateral acceleration applied to a vehicle. A steering angle ϑ of a steering wheel detected by the steering angle sensor 110 and a lateral acceleration detected by the lateral G sensor 111 are input to a traction controller 15 as amounts indicating a degree of turning, i.e., turning degree.
Fig. 37 shows the principle of the lateral G sensor 111. The lateral G sensor 111 is an operational transformer type displacement detection sensor. A core 120 is arranged between a primary coil 121 and two secondary coils 122a and 122b to be movable in a lateral direction of a vehicle. With this arrangement, when the vehicle turns and a lateral acceleration is increased, the core 120 is displaced in the lateral direction in accordance with the lateral acceleration, and an output voltage E shown in Fig. 38 is generated. More specifically, when the output voltage E is measured, the lateral acceleration applied to the vehicle, i.e., the turning degree, can be detected. The lateral acceleration corresponds to the centripetal acceleration GY. In the third embodiment, the lateral acceleration detected by the lateral G sensor 111 is used in place of the centripetal acceleration GY in the second embodiment. When the lateral G sensor 111 malfunctions, the lateral acceleration GY output from the lateral acceleration calculator 112d is is outputted through a selector 112m. The selector 112m is switch by a failure detector 112k.
(1) E > EH or E < EL continues for a predetermined period of time;
(2) ϑ > +A, VB < B, and E < E0 continue for a predetermined period of time; and
(3) ϑ < -A, VB > B, and E > E0 continue for a predetermined period of time.
(ϑ: steering angle, VB: vehicle velocity, A, B: preset values, EH: upper limit, EL: lower limit, EO: reference value)
The traction controller 15 receives the lateral acceleration detected by the lateral G sensor 111 as the turning degree. When the turning degree is increased, the controller 15 controls to decrease a slip rate S and increase a lateral force A during turning, thereby improving turning characteristics. However, when the lateral G sensor 111 malfunctions, the lateral acceleration GY is calculated on the basis of driven wheel velocities output from wheel velocity sensors 13 and 14 for detecting driven wheel velocities, and the slip rate S during turning is decreased on the basis of the centripetal acceleration GY, thereby improving turning characteristics. The malfunction of the lateral G sensor 111 can be detected by the failure detector 112j when one of the following conditions is satisfied:
Thereafter, the operation for calculating the centripetal acceleration GY, and making control on the basis of the centripetal acceleration GY in accordance with the slip rate S to improve turning characteristics is the same as that in the second embodiment shown in Figs. 18A and 18B.
In the first to third embodiments, the reference torque TG is calculated as an axial torque of the driving wheels from the driven wheel velocities, and after the correction torque according to a slip value is subtracted from the reference torque TG to calculate the target torque as an axial torque, the target torque is converted to an engine target torque. However, the reference torque and the correction torque may be calculated after they are converted to an engine torque. | |
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Over the last two decades advances in the understanding of disease at a cellular and molecular level has led to innovative therapies that are based on the administration of cells which have been modified outside of the body. Ex vivo cell therapy is in essence gene therapy delivered by transfer of therapeutic genes to cells in culture, which are then given to the patient to treat fatal infections such as AIDS, or other conditions such as cancer or genetic diseases. These manipulations include the purification and culture of therapeutic cell subtypes, as well as elimination of cells which cause disease (cancer cells or immune cells reacting to the body itself). Gene therapy can be delivered by transfer of therapeutic genes to cells in culture, which are then given to the patient to treat fatal infections such as AIDS, cancer or genetic diseases. For small-scale laboratory methods to become clinically applicable processes, these new therapies require efficient technologies for cell separation, cell production in culture and gene transfer. This book integrates the recent advances in biological and clinical research with developments in cell-based technologies to provide a comprehensive review for clinicians, researchers, biotechnologists and biomedical engineers working in this rapidly developing area. The biotechnology and pharmaceutical industry requires a broad perspective for development of future technologies, and this text will provide then with an excellent overview of this rapidly evolving field.
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About the Editor
Klaus Schindhelm
Klaus Schindhelm received his PhD in chemical engineering in 1978 at the University of New South Wales with a dissertation on patient hemodialysis interactions. The main focus of his research has been the manipulation of body fluids for extra-corporeal therapies ranging from hemodialysis to therapeutic immunoadsorption systems. This work has involved mass transfer studies, kinetic modeling and the investigation of blood material interactions. His interest in cellular therapy has evolved from a background in therapeutic solute manipulation, and is currently developing affinity membrane systems for the preparation of therapeutic cell subsets. Professor Schindhelm is a former chairman of the College of Biomedical Engineers in Australia and is currently the Head of the Graduate School of Biomedical Engineering at the University of New South Wales.
Affiliations and Expertise
University of New South Wales and Graduate School of Biomedical Engineering, Sydney, Australia
Robert Nordon
Dr. Robert Nordon graduated from the School of Medicine at the University of New South Wales (UNSW), Australia, in 1986, and following three years of clinical training commenced his research career at the Centre for Biomedical Engineering, UNSW. Since receiving his PhD in 1994, his central research interest has been the development of biomedical devices for hematopoietic stem cell selection and expansion. The British Columbia Cancer Agency, Canada, awarded him a Physician/Scientist training fellowship in 1996 to study at the Terry Fox Laboratory, Vancouver, where he established flow cytometric techniques for tracking the divisional recruitment of quiescent stem cells by hematopoietic growth factors. He is currently an Australian Research Council postdoctoral research fellow at the Graduate School of Biomedical Engineering, UNSW and is working with the Australian Children’s Cancer Research Institute to develop novel systems for cord blood stem cell enrichment and expansion.
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An asteroid the size of the world’s tallest building will make one of its closest approaches to Earth. According to NASA, the asteroid 7482 (1994 PC1) will pass by on January 18.
The asteroid is estimated to be 1 kilometer across, or more than 3,280 feet tall — more than twice the height of New York’s Empire State Building, which is 1,454 feet tall from base to antenna, and hundreds of feet taller than Dubai’s Burj Khalifa, the world’s tallest building, which is 2,716.5 feet tall.
According to NASA’s Jet Propulsion Laboratory, the space body might come within 1,231,184 miles of Earth. This would be the asteroid’s closest approach to Earth since January 17, 1933, when NASA predicted it came within 700,000 miles of the globe.
As per NASA’s report, the asteroid will pass by Earth again in July this year, but at a far greater distance. It is not expected to sail by Earth again at such a near distance until January 18, 2105, when it is expected to reach within 1,445,804 miles.
The space agency has been tracking this asteroid since it was found in August 1994, and it has been designated as an Apollo asteroid, which means its orbit overlaps that of Earth and has somewhat greater axes. According to NASA, it is also designated as “possibly dangerous” because of its “potential to conduct threatening near encounters to the Earth.”
There are over a million known asteroids, and it is not unusual for many of them to pass close to Earth, with the vast majority of those that do being of little significance. According to NASA, at least five asteroids will pass past the earth on Wednesday and Thursday this week, including one the size of a bus and three the size of a home.
According to Nancy Chabot, a chief planetary scientist at Johns Hopkins University’s Applied Physics Laboratory, there are roughly 25,000 near-Earth asteroids at least 500 feet broad that may be “devastating” if they collide with Earth.
“We’re actually not talking, like, global extinction event, but regional devastation on the area that could wipe out a city or even a small state,” she previously stated. “And so it is a real concern. It is a real threat.”
And, in the event that an asteroid emergency such as the one shown in Netflix’s “Don’t Look Up” occurs in the future, NASA is already working on a solution. NASA launched a spacecraft in November that will collide head-on with a minor asteroid next September as part of a test to see if it is feasible to force a future asteroid off course if it looks that it will collide with the earth.
At 15,000 miles per hour, the Double Asteroid Redirection Test, or DART, will crash with Dimorphos, a 525-foot-wide body. | https://expertistnetwork.com/potential-hazardous-asteroid-to-make-a-close-pass-to-earth-by-jan-18/ |
When is the Bold Center reopening?
Starting Thursday, July 2, the Bold Center will be open to the public from 12-8 p.m.
Why won’t the Bold Center have its usual operating hours?
This is a starting point. To meet current COVID-19 safety protocols, there are increased safety measures and cleaning practices we need to follow, and limits to the number of amenities and facilities we can open. Being open from 12-8 p.m. allows those who work during the day to come to the Bold Center after regular work hours, and also allows those who may be considered vulnerable to visit earlier in the afternoon. Our hope is we will be able to increase our operating hours soon.
What facilities and amenities will be available starting July 2?
Facilities that are permitted to open include:
- Booster Juice and Stuart MacPherson Public Library (already open)
- Paratransit Bus and Community Access Bus for individuals (no group bookings; masks required for all passengers)
- Cenovus Fitness Centre and adjoining fitness studios
- Canadian Natural Walking Track
- Cenovus Fieldhouse 2 (Fieldhouse 1 to open at a later date)
- Meeting rooms (for clubs/group meetings that can follow COVID-19 measures and hours)
- User groups/rentals and programs that can follow COVID-19 measures and hours
- Recreation programs and fitness classes (will be held outdoors when possible, as per provincial recommendations) – For full listing of programs, camps and workshops, please refer to our Summer Programs Pamphlet
What facilities and amenities will NOT be available starting July 2?
- Arenas/ice rinks (at least one sheet expected to open August 4)
- Portage Pool (expected to open August 4)
- Cenovus Child Mind Centre/indoor playground (reopening date TBD*)
- Changerooms, steam rooms and boxing area (reopening date TBD*)
- Personal training services (more details coming soon)
- Fitness centre towel service and locker rentals
- Weddings, funerals and social gatherings, including birthday parties
- Summer sport camps and slo-pitch league
- Laser Tag, Ultimate Challenge obstacle course and other equipment rentals
*Expected to reopen as part of Stage 3 of the Government of Alberta’s Relaunch Strategy.
What can I expect when I arrive at the Bold Center?
For everyone’s safety and wellbeing, all guests will be required to complete a COVID-19 screening before accessing the Bold Center. Staff will greet guests at the main entrance and conduct the screening (the public will not be able to use the back entrance). The screening consists of a checklist, and all personal information collected will be kept confidential. Members will be checked in, while pre-booked drop-in users will be encouraged to pay over the phone with a credit card prior to arriving (in-person payments will also be accepted).
Please stay home if you display any signs/symptoms of COVID-19, as you will not be permitted to enter the Bold Center. Common COVID-19 symptoms include but are not limited to:
- Fever
- Shortness of breath
- Cough
- Runny nose
- Sore throat
Do I need to wear a mask?
Wearing a mask is not recommended for recreation program or fitness class participants. We do encourage users to follow physical distancing protocols at all times (except those in family/friend cohorts). You may see Bold Center employees wearing masks when physical distancing is not possible, or if they simply feel more comfortable wearing masks.
Masks are required for Community Access Bus and Paratransit Bus passengers and drivers.
What measures are you taking to ensure user safety?
- Limited hours and limited numbers of people for the time being
- Pre-booked times and screening of all facility users/program participants
- Protection screens and signage installed throughout facility
- Staff wearing masks when physical distancing of at least 2 metres is not possible
- Hand sanitizer stations available upon entry/exit
- Extra sanitizing wipes available in fitness areas and classes
- Increased cleaning measures and cleaning frequency
- Staff reminding users to respect physical distancing protocols and other safety measures
- Wristbands not being issued for the time being, as staff will be tracking attendance and usage
- Payments accepted by phone for pre-booked drop-ins (in-person payments also accepted, with terminals cleaned after every use)
When and how can I get in to work out?
To start, the Cenovus Fitness Centre will be limited to a maximum of 20 users per one-hour time slot. Members and passholders will have priority to pre-book.
Time slots:
- 12-1 p.m.
- 1:30-2:30 p.m.
- 3-4 p.m.
- 4:30-5:30 p.m.
- 6-7 p.m.
Staff will clean in between time slots, and thoroughly clean the entire area at the end of each day.
Will cardio equipment be spaced out, or will there be limited usage allowed?
We can’t move all of our cardio equipment, so these pieces of equipment will have 30-minute time limits for the time being, to ensure all users have an opportunity to use them. Users can change cardio machines after 30 minutes, though.
How do I book my workout times?
Members and passholders can call to book and reserve time slots. Please call the Bold Center at (780) 623-3829 and press 0 to speak to a customer service representative.
Drop-ins are welcome and will be accepted if space permits in the fitness areas. We strongly encourage both members and drop-in guests/users to call ahead to avoid disappointment.
There won’t be public access to locker rooms and steam rooms. Users should arrive in workout clothing (clean indoor shoes still required). Day use lockers are available to store belongings, and these lockers will be cleaned after every use.
Can I book multiple dates/times at once?
This is our first time handling this type of situation, so for now members/passholders will be given priority to call and more than one workout time slot ahead of time. If we experience high demand and can’t accommodate user volumes, we may need to reassess. Drop-in guests/users can call up to 24 hours in advance to book an available space.
Do I need to book times to use Cenovus Fieldhouse 2 or the Canadian Natural Walking Track?
No, because these areas allow for easier physical distancing, but user numbers will still be monitored to ensure COVID-19 safety protocols are being followed. As the Province updates restrictions, we will post new information outside of all activity areas. Users are encouraged to check with staff monitoring these areas and, where possible, bring their own equipment like balls, racquets, etc. to reduce contact and equipment-sharing. The middle lane of the Canadian Natural Walking Track will be closed to allow distancing and passing in the outside lane.
What other changes can I expect when using Cenovus Fieldhouse 2?
A limited number of users will be allowed in the Cenovus Fieldhouse at one time, so everyone can practice physical distancing. A maximum of 10 people will be permitted on each court, unless the group is a family/friend cohort, in which case up to 15 people will be permitted. Employees will have discretion to adjust these numbers if necessary, depending on the situation.
Users can stay in the Cenovus Fieldhouse for a maximum of one hour, as a courtesy to others who may be waiting. If no other users are waiting, then this time limit may be extended. Users must be actively using the fieldhouse (not simply loitering or socializing). We ask that users congregate and socialize outside the Bold Center as much as possible.
Equipment-sharing is not allowed unless all participants are from the same household. This does not include pucks and soccer balls, as long as participants are not touching the items with their hands. | https://boldcenter.ca/news/covid-19-q-a/ |
Potato dumpling in a gorgonzola cheese sauce, served with speck (cured meat), rucola, and walnuts.
Belgian endive and gorgonzola cheese salad, dijon mustard dressing, and toasted walnuts.
Bice’s signature: classic braised veal shank ossobuco with saffron risotto.
Homemade baked eggplant parmigiana. Garnished with basil pesto.
Thinly sliced wild salmon scaloppini with black truffle and white wine sauce, on a lemon rosemary risotto.
Italian thinly sliced cured meat with gorgonzola cheese, Parmesan, and olives.
Caprese of buffalo mozzarella, vine ripe tomatoes, herloim tomatoes and basil julienne with extra virgin olive oil.
24 months aged prosciutto san daniele with fresh burrata and apple tempura fritters.
Crispy flash fried calamari, prawns, fresh zucchini and mushrooms with a spicy tomato sauce.
Tartar of fresh ahi tuna with avocado, fresh basil, teriyaki glaze, and onions.
Coconut breaded shrimp over a mango, avocado and frisee salad with sweet and spicy sauce.
Vegetable minestrone drizzled with basil pesto.
Mixed leaf salad with shaved carrots and cherry tomatoes in a balsamic vinegar dressing.
Caesar salad with hearts of romaine lettuce and croutons.
Radicchio, endive and arugula salad with Parmesan cheese, pine nuts, and lemon dressing.
Baby spinach salad with green apple, almonds, goat cheese, and apple vinegar.
Fresh Mediterranean sea bass grilled on a cedar wood plank, garnished with grape tomatoes, Balsamic truffle vinaigrette and sautéed spinach.
Sesame crusted ahi tuna steak sliced in a saffron potato, green beans, seaweed and teriyaki sauce.
Grilled 14oz organic milk feed veal chop, served with roasted potatoes and asparagus.
Bice’s signature: veal milanese with arugula and cherry tomato salad in a balsamic vinegar dressing.
8oz roasted beef tenderloin in a barolo wine sauce, asparagus, baby carrots and crispy potato dumpling.
Pan seared chicken breast with a lemon and capper sauce, served with mashed potato.
Pan fried chicken milanese style with arugula salad and cherry tomatoes in a balsamic dressing.
Penne pasta in a spicy tomato sauce, extra virgin olive oil.
Ravioli stuffed with braised beef, veal and spinach in a mushroom cream sauce.
Homemade fettuccine pasta in a sicilian pistachio pesto sauce with cream and speck.
Beef tortellini in a 24 months aged parmesan cheese sauce with green peas and prosciutto.
Pappardelle with mozzarella cheese, fresh basil in a tomato cream sauce.
Fettuccine in a classic slow braised bolognese meat sauce.
Spaghetti with fresh maine lobster and cherry tomatoes.
Linguine with fresh mixed seafood in a tomato red sauce.
Linguine with clams, extra virgin olive oil, flavored with basil and grape tomatoes.
Potato dumpling in a basil pesto sauce.
Traditional oven baked lasagna with bolognese meat sauce.
Traditional saffron risotto with ossobuco sauce. | https://www.ubereats.com/fi-US/fort-myers/food-delivery/bice-ristorante/5ZbgRaVRT-mhPEIwGGyp-A/ |
6636656271 has 8 divisors (see below), whose sum is σ = 10113000064. Its totient is φ = 3792375000.
The previous prime is 6636656261. The next prime is 6636656317. The reversal of 6636656271 is 1726566366.
It is a sphenic number, since it is the product of 3 distinct primes.
It is not a de Polignac number, because 6636656271 - 25 = 6636656239 is a prime.
It is a super-3 number, since 3×66366562713 (a number of 30 digits) contains 333 as substring.
It is a Duffinian number.
It is a self number, because there is not a number n which added to its sum of digits gives 6636656271.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (6636656261) by changing a digit.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 158015605 + ... + 158015646.
It is an arithmetic number, because the mean of its divisors is an integer number (1264125008).
Almost surely, 26636656271 is an apocalyptic number.
6636656271 is a deficient number, since it is larger than the sum of its proper divisors (3476343793).
6636656271 is a wasteful number, since it uses less digits than its factorization.
6636656271 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 316031261.
The product of its digits is 1632960, while the sum is 48.
The square root of 6636656271 is about 81465.6754160917. The cubic root of 6636656271 is about 1879.2437231787.
The spelling of 6636656271 in words is "six billion, six hundred thirty-six million, six hundred fifty-six thousand, two hundred seventy-one". | http://www.numbersaplenty.com/6636656271 |
References Abstract Scientific writing and publication are essential to advancing knowledge and practice in public health, but prospective authors face substantial challenges. Authors can overcome barriers, such as lack of understanding about scientific writing and the publishing process, with training and resources. The objective of this article is to provide guidance and practical recommendations to help both inexperienced and experienced authors working in public health settings to more efficiently publish the results of their work in the peer-reviewed literature.
How to write an effective title and abstract and choose appropriate keywords Key takeaways: Without the title, abstract, and keywords—the key marketing tools for research papers—most papers may never be read or even found by interested readers. The abstract should provide a quick and accurate summary of the paper, to help the reader decide whether the rest of the paper is worth reading.
Keywords ensure that your paper is indexed well by databases and search engines, and thus improve the discoverability of your research.
Therefore, keywords should be selected after careful consideration. A BELS-certified editor known for her tireless pursuit of excellence and sharp eye for detail. Nov 04, 1. A negligent or sloppy attitude towards these three vital elements in the research paper format would be almost equivalent to leaving the accessibility of the research paper up to chance and lucky guessing of target words, indirectly making the effort and time expended on the research and publication process almost null and void.
It could be said that the keywords, title, and abstract operate in a system analogous to a chain reaction.
This functional advantage alone serves to make an abstract an indispensable component within the research paper format. However, formulating the abstract of a research paper can be a tedious task, given that abstracts need to be fairly comprehensive, without giving too much away.
This is mainly because if readers get all the details of the research paper in the abstract itself, they might be discouraged from reading the entire article. The title, abstract, and keywords: Without them, most papers may never be read or even found by interested readers Most electronic search engines, databases, or journal websites will use the words found in your title and abstract, and your list of keywords to decide whether and when to display your paper to interested readers.
The title and abstract are often the only parts of a paper that are freely available online. While busy journal editors may use the abstract to decide whether to send a paper for peer review or reject it outright, reviewers will form their first impression about your paper on reading it.
Good research paper titles typically 10—12 words long use descriptive terms and phrases that accurately highlight the core content of the paper. How to write a good title for a research paper Journal websites and search engines use the words in research paper titles to categorize and display articles to interested readers, while readers use the title as the first step to determining whether or not to read an article.
Descriptive abstracts, usually used in the social sciences and humanities, do not give specific information about methods and results. Ask a Question In this section, we focus on how to write a research paper abstract that is concise and informative, as such abstracts are more commonly used in scientific literature.
Beautifully Designed Conference Presentations Effective conference presentations mean slideshows need to be clear, succinct and impactful. As scientists ourselves, we have considerable experience in making slideshows for oral presentations, and can offer you guidance. We can design your presentation or rework an existing one to make you stand-out in a conference! How to Read and Respond to a Journal Rejection Letter Vivian Siegel Public Library of Science San Francisco A fter putting your best work and thoughts and efforts into a manuscript and sending it off for publication, the day of decision arrives. As you open the letter a wave of anger sweeps through your Most scientific Only a few. How to Write a Paper in Scientific Journal Style and Format (pdf) Bates College 1 Reporting Statistical Results in Your Paper Overview The results of your statistical analyses help you to understand the outcome of your study, e.g., whether or not.
You can follow the same strategy to write a structured abstract; just introduce headings based on the journal guidelines. Here are some steps with examples you can follow to write an effective title: What is my paper about?
What were the results?
My paper studies whether X therapy improves the cognitive function of patients suffering from dementia. It was a randomized trial. I studied 40 cases from six cities in Japan.
There was an improvement in the cognitive function of patients. Use your answers to list key words.Keywords: Abstract, preparing a manuscript, writing skills INTRODUCTION This paper is the third in a series on manuscript writing skills, published in the Indian Journal of Psychiatry.
assist with the preparation of a manuscript for a scientific journal.
Before writing a first draft, it is important to establish that the topic of the manuscript is likely to be consistent with the focus of the journal. HOW TO WRITE A PAPER FOR A SCIENTIFIC JOURNAL. How to write a manuscript.
Step-by-step guide. Model manuscript. A manuscript usually has the following structure: Introduction Body Conclusion The three parts are explained on the following slides. Abstract. The objective of the course described here is to train undergraduate students to write a scientific manuscript.
The students participate in selection of a current topic in contemporary genetics or molecular biology by choosing the most interesting paper of a given year. Robert S. Day, How to Write and Publish a Scientific Paper, 4th edition, Oryx Press, Phoenix, Earlier editions also good.
A bit more advanced, intended for those writing papers for publication. Oct 31, · Preparing to write a manuscript Background information The question or hypothesis formulated by the investigator is the common starting point . | https://denypelusuxem.r-bridal.com/how-to-write-a-scientific-manuscript-ppt-48853fb.html |
Welcome back to the next video in the 9 part Virtual Garden Tour of the Rock Creek Learning Garden!
Even with campus closures, Learning Gardens are continuing to flourish! The Rock Creek Learning Garden is the largest Learning Garden at PCC. It comprises 3.5 acres of fruit trees, vegetables, an observation bee hive, a worm nursery, cob oven and other sustainably designed structures in a garden dotted with sculptural works of art all initiated by students at PCC. This summer, the Rock Creek Learning Garden Coordinator – Miriam Latzer has created us a virtual tour of the garden! With 9 videos total, Miriam explains gardening techniques used at Rock Creek, highlighting features, such as the Three Sisters – Corn, Squash and Beans.
Below is the second video explaining the Three Sisters Gardening technique used in the garden.
Start the discussion
PCC offers this limited open forum as an extension of the respectful, well-reasoned discourse we expect in our classroom discussions. As such, we welcome all viewpoints, but monitor comments to be sure they stick to the topic and contribute to the conversation. We will remove them if they contain or link to abusive material, personal attacks, profanity, off-topic items, or spam. This is the same behavior we require in our hallways and classrooms. Our online spaces are no different. | https://www.pcc.edu/sustainability/2020/09/10/rock-creek-learning-garden-virtual-tour-video-2/ |
By Sarah D. Sparks. Cross-posted from Inside School Research.
Want to find a better teacher for English-language learners? Start by looking for teachers who add the most value for any students, rather than limiting the search to those who may have had specialized training to work with ELLs.
That's the conclusion of a new Stanford University study, "Is a Good Teacher a Good Teacher for All?" in online preview in the journal Education Evaluation and Policy Analysis. Education researchers Susanna Loeb, James Soland, and Lindsay Fox used a value-added measure to look at the effectiveness of teachers both with and without bilingual certification in Miami-Dade public schools in Florida.
They analyzed teachers' effectiveness in reading and in math, with English-learners (both current and those who had been considered not proficient in English within the last three years) and those fluent in English. The researchers conducted separate analyses of English-learners and non-ELLs in the same school and the same classroom, to correct for potential differences in how students are sorted to teachers.
Loeb and her colleagues found that generally, a great teacher is great for all students, and an ineffective teacher is pretty much ineffective for everyone, too. In math, nearly six in 10 teachers who rated in the top 20 percent of effectiveness for students fluent in English were also in the top quintile for English-learners. In reading, 42 percent of teachers in the top 20 percent for non-ELLs were also most effective for ELLs.
The researchers also noted that more than half of teachers would be rated in different quintiles of effectiveness under value-added measurements if they were being judged on ELLs or non-ELLs alone. However, the differences are rarely very large. A very effective teacher might be in the top 20 percent for ELLs and the top 40 percent for all students, for example, and a less effective teacher might be in the bottom 20 percent of value-added scores for ELLs and the bottom 40 percent of value-added for non-ELLs.
But educators are not likely to be misclassified as ineffective when they are really highly effective: Fewer than 4 percent of teachers in math were rated most effective for non-ELLs but least effective for ELLs or vice versa. For reading, that was about 7 percent.
Of course, this doesn't mean English-learners don't benefit from having a teacher who specializes in teaching students learning a new language. The researchers found teachers who were fluent in Spanish, or had a bilingual certification, were more effective with English-learners than teachers who were not as familiar with students' native language and teaching ELLs, all else being equal. That makes sense.
But Loeb and her colleagues cautioned that Miami-Dade is an unusually homogenous district, where English-learners are overwhelmingly Spanish speakers, and many adults also speak both English and Spanish fluently. The effects of having a bilingual certification may be more or less important in a district like New York City, boasting students and teachers alike who speak dozens or even hundreds of different native languages.
"Finding a better teacher for English-learners is at least as much if not more a question of finding an effective teacher, as it is a question of finding a teacher who specializes in English-learners," they concluded. | http://blogs.edweek.org/edweek/learning-the-language/2014/10/un_gran_maestro_in_any_languag.html |
Q:
For Loop for a Fourier Series Equation
How can I plot the Fourier Series equation below, using a for loop where I can change n, instead of writing out the cos(x) + cos(2x) + cos(3x), etc.?
My script is below:
import matplotlib.pyplot as plt
import numpy as np
fig = plt.figure()
pi = np.pi
x = np.linspace(-pi,pi,100)
ao = (1/(2*pi))
y = ao + (1/pi)*(np.cos(x)+np.cos(2*x)+np.cos(3*x) + np.cos(4*x)+np.cos(5*x)+np.cos(6*x) + np.cos(7*x) + np.cos(8*x) + np.cos(9*x)+np.cos(10*x))
plt.plot(x,y)
plt.show()
A:
This is all you need:
n = 10
x = np.linspace(-pi,pi,100)
y = (1/(2*pi)) + (1/pi)*(sum(np.cos(i * x) for i in xrange(1, n)))
plt.plot(x,y)
plt.show()
Basically you just have a list comprehension which does the sum for you:
sum(np.cos(i * x) for i in xrange(1, n))
A:
You can use a list comprehension:
n = 10
y = ao + (1/pi) * sum([np.cos((i+1)*x) for i in range(n)])
| |
Chopping boards, garlic crusher, knives, measuring spoons, 2 large saucepans, wooden spoon, weighing scales, colander, tin foil, frying pan or skillet.
Heat the oil in a large saucepan and cook the onion and garlic until soft.
Add the tomatoes and cook for 3 minutes until they start to soften. Add the basil and stir.
Bring water to the boil in a large saucepan, add the pasta and cook for 10-12 minutes. Drain the pasta.
Add the tomatoes to the pasta and stir. Cover with tin foil to keep warm and set aside.
Season the steak with black pepper.
Heat a frying pan or skillet and cook the steak for 4 minutes on each side.
Remove the steak from the pan and cut into thin slices.
Serve the pasta with the steak slices and top with the crumbled goats cheese. | https://www.food4life.org.uk/recipes/beef-and-pasta |
Rain helps slow Alaska wildfire that prompted evacuations
ANCHORAGE, Alaska (AP) — Some rain helped firefighters battling an Alaska wildfire that prompted evacuations.
About a half inch fell into early Monday, allowing crews to build more fire breaks to help control the wildfire started by lightning June 21.
“It’s not really like a season-ending type of rain, it’s more like a slowing,” said a spokesperson for the fire, Mark Enty.
The fire has been burning near the community of Anderson. Evacuation orders were place for all properties accessed by roads, trails or driveways on the west side of the Parks Highway from mileposts 269 to 275.
The city of Anderson, located about 80 miles (130 kilometers) southwest of Fairbanks, is not under an evacuation order.
At least one home has been confirmed to have been lost, and Enty said Denali Borough officials will make an official assessment of other structures.
The fire is estimated to be 110 square miles (284.90 square kilometers) . | https://apnews.com/article/wildfires-fires-alaska-evacuations-fairbanks-c45c26d398afb64d5279dd64041eb43d |
.
Sovereign
Coburg Green , Exeter, EX2 7PZ, Exeter
- Bedrooms :3
- Number of occupants:5
3 bed 4 person semi-detached house with private garden & allocated parking. Close to schools, transport links and local amenities.
Two weeks rent required in advance.
|Property reference||3548108|
|Area||Exeter|
|Landlord||Sovereign|
|Property type||House|
|Floor level||Ground floor|
|Closing date||14/06/2021|
|Bedrooms||3|
|Number of occupants||5|
|Heating type||Full gas central heating|
|Energy efficiency||C|
|Double glazed||Yes|
|Parking||Allocated Space|
|Lift||No|
|Garden||Yes|
|Pets allowed||Pets with permission|
|Rent||£111.6Detail|
|Accessible housing category||5-General Needs|
|Rent frequency||Weekly|
|Sheltered||No|
|Age restriction||No|
|Minimum age of at least one person||NA|
|Local connection||No|
|Contact details||Yes|
Contact details
Contact Number :
0300 5000 926
Contact Email : | https://www.devonhomechoice.com/property-detail/519645263-3548108 |
We’ve all fallen down an internet rabbit hole from time to time—you start looking for a good place to get a burrito for lunch, and an hour later, you realize you’re breathlessly reading about the lifespan of a waterbug on the other side of the planet during the 1700s...and you're still starving. The fun part comes, however, when seemingly unlikely topics crash into each other, echoing observations and sentiments, as happened to me this morning.
There is an energizing boundlessness to [the concept of] removing limits to what is possible in order for creativity to take on less damaging forms and really thrive. But is this the case? Some time ago, back in the mid 2000s, I was working on a small project exploring the impact of digital technologies on music. As part of that project I was speaking to a recording engineer about their practices.
We reflected on the changing technologies of music production, the impact of the infinite number of tracks in recording studios, and the unlimited possibilities of post-production. We discussed whether creativity might actually be hampered by these endless options, since at least in part it is about overcoming limits, and is not always, as Mould suggests, about creating something from nothing. In a much larger follow up project a few years later, we found that the recording engineer actually sees it as their role to find ways to realize the sonic vision of the recording artist even as it clashes against the material constraints of the studio. Here, the constraints are an active part of the way that such artistic creations are made real.
… As the recording engineer suggested to me, we might use the boundaries we face to inspire creative action and help us to imagine alternatives.
Of course, as Beer says at the top of that excerpt, sometimes the boundaries are really the artists themselves, paralyzed into creative indecision thanks to too many options.
That idea fit ironically with the next entry in my Google search: a Spin article recounting a Rolling Stone article recounting an audiobook recounting the Beastie Boys’ new memoir, Beastie Boys Book.
So, in essence, Caldato saw the Boys’ inability to narrow down their artistic options as the boundary they had to overcome. Ironically, venting his frustration led to the trio seeing him as their greatest obstacle, whether for real or in jest, and that finally inspired them to complete the now legendary track. | https://www.prosoundnetwork.com/pro-sound-news-blog/audio-obstacles-fueled-recording-the-beastie-boys-sabotage-engineer-book-rock-rap-hiphop-punk |
In March 2011, about 3.8 million people left Syria as an uprising began against the government, and they went to camps in many countries, including Jordan. People at one camp in Jordan help the refugees, especially the children and young people, by encouraging them to play football.
A woman who helps at the camp explained that the children need to play and be kids so that they can feel better about themselves. She said that they need to forget the bad things that happened to them. Playing football gives them hope that they can feel normal and happy again.
Difficult words: uprising (when people fight their government), refugee (a person who left his country), encourage (to tell someone nicely to do something).
You can read the original story and watch the video in the Level 3 section.
Do you think playing football helps the children?
LEARN 3000 WORDS with NEWS IN LEVELS
News in Levels is designed to teach you 3000 words in English. Please follow the instructions
below.
How to improve your English with News in Levels:
Test
- Do the test at Test Languages.
- Go to your level. Go to Level 1 if you know 1-1000 words. Go to Level 2 if you know 1000-2000 words. Go to Level 3 if you know 2000-3000 words.
Reading
- Read two news articles every day.
- Read the news articles from the day before and check if you remember all new words.
Listening
- Listen to the news from today and read the text at the same time.
- Listen to the news from today without reading the text.
Writing
- Answer the question under today’s news and write the answer in the comments.
Speaking
- Choose one person from the Skype section.
- Talk with this person. You can answer questions from Speak in Levels. | https://www.newsinlevels.com/products/football-helps-people-in-jordan-level-2/ |
reinforcers, biases, or effective problem-solving strategies).
The
article must meet the following criteria:
1.The
article must be from a peer-reviewed journal.
2.The article must be obtained from the Library.
3.The
article must be a research study, rather than a literature review (i.e., the
article has to have methods, results, and discussion sections).
4.The
article must utilize a cognitive or behavioral theory, model, or effect.
5.The
purpose of this article review is to get you to think critically about an area
of cognition or learning. After reading your chosen article, address the
following questions. Use subheadings to differentiate between the various
aspects of your review. Remember, APA guidelines can be found in the APA Style
Guide, located in the Student Success Center.
Major
Findings/Conclusions:
1.Be
sure to include the major findings of the study.
2.What
conclusions did the researchers draw from the data?
Implications
for the Field of Psychology (how the findings could be used/applied in the
field):
1.Include
how the results of the study can be applied (e.g., why are the findings of the
study important?). These may be the implications the authors put forth, or your
own ideas (be sure to cite if they are not your ideas).
2.How
would psychology/education/counseling professionals benefit (learn) from the
findings?
3.How
might the results improve knowledge or application in the field? What should
psychology professionals “take away” from the findings?
Method/Participants:
1.Describe
the basics of how the study was conducted. What procedures were used?
2.Who
were the participants?
Strengths/Limitations
of the Study:
1.Include
at least one strength AND one limitation you saw in the study.
2.Explain
why you believe each is a strength or limitation. Hint: study findings are not
“strengths” in and of themselves.
The
article review should be 1,000-1,250 words. Include a minimum of three
scholarly articles.
Prepare
this assignment according to the guidelines found in the APA Style Guide,
located in the Student Success Center. An abstract is not required.
This
assignment uses a rubric. Please review the rubric prior to beginning the
assignment to become familiar with the expectations for successful completion.
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are required to submit this assignment to LopesWrite. Please refer to the
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Note: This benchmark
assignment assesses the following programmatic competency: 4.4: Explain the
importance of maintaining knowledge of current trends in psychology. | https://prowriters.firstclassessaywriters.com/2020/01/29/solutionbenchmark-article-review/ |
Crime Scene Investigation
Introduction:-
Most police investigations begin at the scene of a crime. The scene is simply defined as the actual site or location in which the incident took place. It is important that the first officer on the crime scene properly protect the evidence. The entire investigation hinges on that first person being able to properly identify, isolate, and secure the scene. The scene should be secured by establishing a restricted perimeter. This is done by using some type of rope or barrier. The purpose of securing the scene is to restrict access and prevent evidence destruction.
Once the scene is secured, the restrictions should include all nonessential personnel. An investigation may involve a primary scene as well as several secondary scenes at other locations. On major scenes a safe space or comfort area should be designated at the crime scene to brief investigators, store needed equipment, or as a break area.
In critical incident management the protocol that is being taught today identifies a three layer or tier perimeter. The outer perimeter is established as a border larger than the actual scene, to keep unlookers and nonessential personal safe and away from the scene, an inner perimeter allowing for a command post and comfort area just outside of the scene, and the core or scene itself. An extreme advantage will be seen by taking the time to properly teach the uniform officers and first responders to evaluate and secure the scene.
Services in this vertical are as under:-
Preserving and protecting the crime scene so that evidence can be recovered and recorded without being lost, spoilt or destroyed.
Finding out what evidence is needed, deciding the best way to recover it and collecting it as required.
Recording the scene using photography and video.
Searching for evidence footprints and for marks left by tools or weapons.
Developing, recording and capturing fingerprint evidence.
Locating, recording and recovering evidence such as fibres, blood, hair, paint or glass using various techniques.
Putting samples into protective packaging and sending them for analysis.
Keeping written records, producing statements and updating systems with details of evidence.
Bloodstain Pattern Analysis:-
Bloodstain Pattern Analysis (BPA) is the science of studying the bloody aftermath of violent crime and accidents to help investigators gather evidence.
Characterizing evidence and interpreting the results through laboratory analysis.
Reconstructing and representing events.
Preparing reports and presenting evidence in court.
Laser Scanning:-
ESR is using this new technology to record a crime scene, accurately measuring the position, size and orientation of evidence. Laser scanning can also superimpose complex evidence such as bloodstain patterns and bullet trajectories.
Footwear and Tyre Impressions:-
Our scientists can identify impressions as belonging to a shoe or tyre through matching class (pattern) and individualising (damage) characteristics present on both the impression and shoe/tyre. They are experienced at preserving and/or recording impressions and enhancing faint impressions.
Firearms and Toolmarks:-
ESR firearm investigation services include comparison of recovered projectiles and cartridges to identify the firearms that fired them; tracking of projectile trajectory; identifying residues associated with firing a firearm and estimating the distance between firearm and target. Our toolmark investigation services include comparing toolmarks at the scene with tools recovered from suspects.
Vehicle Accident Investigations:-
Our services include investigation of vehicles involved in traffic accidents. Our specialist staff can identify vehicles in a “hit and run” situation by means of paint transferred between vehicles; body filler; glass and car parts at the accident scene; fabric traces or impressions on a vehicle establishing exact place of impact. Our DNA profiling of blood and other trace evidence techniques assist driver identification; and we can provide analysis of the driver’s blood for alcohol and drugs.
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Please use this identifier to cite or link to this item:
http://hdl.handle.net/10773/6136
|Title:||Finite element and experimental cortex strains of the intact and implanted tibia|
|Author:||Completo, A.|
Fonseca, F.
Simões, J. A.
|Keywords:||promixal tibia|
Knee prosthesis
Synthetic tibia
Finite element analysis
Strain gauge measurements
|Issue Date:||2007|
|Abstract:||Finite Element (FE) models for the simulation of intact and implanted-bone find their main purpose in accurately reproducing the associated mechanical behavior FE models can be used for preclinical testing of joint replacement implants, where some biomechanical aspects are difficult, if not possible, to simulate and investigate in vitro. To predict mechanical failure or damage, the model should accurately predict stresses and strains. Commercially available synthetic femur models have been extensively used to validate finite element models, but despite the vast literature available on the characteristics of synthetic tibia, numerical and experimental validation of the intact and implant assemblies of tibia are very limited or lacking. In the current study, four FE models of synthetic tibia, intact and reconstructed, were compared against experimental bone strain data, and an overall agreement within 10% between experimental and FE strains was obtained. Finite element and experimental (strain gauge) models of intact and implanted synthetic tibia were validated based on the comparison of cortex bone strains. The study also includes the analysis carried out on standard tibial components with cemented and noncemented stems of the RE C Sigma Modular Knee System. The overall agreement within 10% previously established was achieved, indicating that FE models could be successfully validated. The obtained results include a statistical analysis where the root-mean-square-error values were always < 10%. FE models can successfully reproduce bone strains under most relevant acting loads upon the condylar surface of the tibia. Moreover FE models, once properly validated, can be used for preclinical testing of tibial knee replacement, including misalignment of the implants in the proximal tibia after surgery, simulation of long-term failure according to the damage accumulation failure scenario, and other related biomechanical aspects.|
|Peer review:||yes|
|URI:||http://hdl.handle.net/10773/6136|
|DOI:||10.1115/1.2768382|
|ISSN:||0148-0731|
|Appears in Collections:||DEM - Artigos|
Files in This Item:
|File||Description||Size||Format|
|Artigo_original.pdf||Documento principal||1.13 MB||Adobe PDF|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated. | https://ria.ua.pt/handle/10773/6136 |
We grew up watching movies like The Terminator, Star Wars, and The Matrix; weaving our AI dreams since our childhood. The term ‘Artificial Intelligence’ was coined in 1956 by John McCarthy, but it is in the recent years that AI has experienced a resurgence as we are now being introduced to its real-world applications.
Today, artificial intelligence is all around us, at times we don’t even realize it; all of us at some point have been assisted by Siri or Google Assistant, have heard about a self-driving car, and have definitely received product and movie recommendations from Amazon and Netflix respectively. AI is already a part of our daily lives and its realm is likely to grow in the coming years. Now, terms like ‘Machine Learning’ and ‘Deep Learning’ have also started gaining ground. A lot of us use ‘Artificial Intelligence’ and ‘Machine Learning’ interchangeably, no doubt both of them are connected, but in effect, both of them are vastly different things.
In this blog, I’ll try to explain what machine learning and artificial intelligence actually mean, how they are correlated, and clear the differences between the two.
What is artificial intelligence?
It is a state when a machine develops an ability to function with little or no human involvement. Once the sample data and algorithms are fed, machines can take decisions based on predefined parameters and conditions. With AI, machines can carry out tasks by planning processes, understanding verbal context, recognizing images and sounds, and using all of these data to solve problems that otherwise require human intelligence.
Discover what, why and how of Vision AI at the Edge
Date: Wednesday, April 21, 2021
Webinar agenda
- What is Vision AI at the Edge
- Why vision AI at the edge is a game-changer
- Applications of Vision AI at the Edge
- Industrial use cases for accelerating AI at the Edge
- Q & A
And now, what is machine learning?
In simple words, machine learning is the most proficient way to achieve artificial intelligence. When computer systems have ML, they have the ability to “learn” with data and perform tasks even when they are not programmed to do so. This is done by relying on already known algorithms and analyzing existing data, which provides them with the competence to solve unfamiliar problems without the need to hard code software routines.
How are they correlated?
Machine learning is basically the ability to learn without being explicitly programmed. So, we can say that artificial intelligence can be achieved even without machine learning, but it would require developing billions of lines of code that reflect various decision trees and complex rules to accomplish any pre-known tasks.
The concept of artificial intelligence was surrounded around the belief that we could program the computer systems with all the code that is required to “mimic” human behavior. Later, we realized that it isn’t feasible or practically possible to teach machines each and everything about this world, instead we need machines to learn on their own and solve problems or make decisions. This is why machine learning plays a significant role in achieving artificial intelligence.
According to a research by Domo, users of the Internet generated approximately 2.5 quintillion bytes of data each day in the year 2017.
Based on this, we can say that we have an immense amount of training data to feed to our systems so that they can use machine learning to learn patterns and predict future data behavior. In addition to having training data, businesses also need knowledge of algorithms that can be used to build machine learning models.
The majority of industries today are dealing with humungous data, which can be better used by applying machine learning and artificial intelligence technologies. Machine learning can help them proactively address business problems and take crucial business decisions.
Here’s a table that shows how different industry verticals can make use of machine learning algorithms:
In plain words, you can say that machine learning makes it possible for us to make our AI dreams real. | https://www.softwebsolutions.com/resources/use-of-machine-learning-and-AI.html |
Hi my name is Keaton, I’m 24 and currently living in West End but am looking to move into a smaller, quieter house, and a much more comfortable and welcoming household. I would describe myself as a kind, friendly and considerate person and quite easy to live with. I would say I’m quite a tidy person, especially when it comes to shared spaces and am looking for like minded people to share a place with.
Available 1 September 2020
Erin
Early bird
$185/week•21 year old female
Hi potential housemates, I'm an easy going person and bartend for work, I also study primary education. I'm tidy and I'm happy to keep to myself but also enjoy being sociable. I love animals and am happy to share a house with some furry friends. I do have a Rhodesian Ridgeback named Toby. He's a quiet, playful, and well-behaved boi, and loves his cuddles.
Available 8 December 2020
Maryanne
Free to message
$250/week•20 year old female
My name is Mary-Anne, I am 20 and studying a Batchelor of Sports and Exercise Science! I am a well presented, enthusiastic, exceptionally mannered and respectful person. I have lived in shared accommodation for over a year and am looking for a change of scenery. I look forward to hearing from you and can provide an array of references too!
Available Now
Sophie Tiver
Early bird
$180/week•21 year old female
Hey guys, I'm a 21-year-old dual degree nursing/paramedic uni student in my third year. So I'm super busy at uni and placement. I'm super easygoing and easy to live with as I'm clean and tidy. I like my own space, but I also like a conversation. I would love to move in with a group in their 20's who are fun and easy-going.
Available Now
Carolyn
Early bird
$250/week•30 year old female
I am 30 years old, work full time, friendly, pay my rent on time and am looking for a nice, quiet place to move to. Am specifically seeking air conditioned ensuite room in Brisbane. Not at all interested in 'party houses'. Please msg me if you have something :)
Available Now
Chelsea
Early bird
$200/week•23 year old female
I’m Chelsea, i’m 23 and just returned from Canada on a working visa. Looking for a place to stay for the next few months before returning to Canada again. I’m clean, respectful, social, and understand people’s boundaries. I love adventuring and meeting new people but also like to have relaxed days reading or going to the beach. Looking for relaxed housemates and hoping to move in asap. Looking for something that is flexible as I’m not sure when i’m flying back - ideally 3 months or so
Available Now
Lucy
Free to message
$175/week•21 year old female
Hey! I am a really social person who works 2 jobs and studying MPH full time, so looking to get closer to my uni (Kelvin Grove QUT). I'm looking to join a friendly house that are respectful but also down to have a few drinks or hang out, even cook a few meals together. Some weekends or weeks I'll be up the sunshine coast where my boyfriend lives, where i love the beach and im learning to surf. Im really friendly so happy to meet up beforehand or connect on socials!
Available Now
Chloe
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$200/week•17 year old female
I am 17 years old, friendly and love meeting new people. I am a boarder right now but i graduate school in November and is looking for a place to live soon after that. I am currently unemployed however will soon be looking for a part-time/full-time job before going to uni. weekly rent will still be guaranteed. My family lives in Dubai and France so finding a nice and friendly accommodation would be appreciated. I don't mind living with older people, majority of my friends are 19+. I like to say i'm tidy and wont be too noisy or disturbing. I respect privacy and i always clean up after myself and others if needed. | https://flatmates.com.au/people/newmarket-4051?page=12 |
Abstract:Recently, low-dose computed tomography (CT) has become highly desirable due to increasing attention to the potential risks of excessive radiation. For low-dose CT imaging, ensuring image quality while reducing radiation dose is a major challenge. To facilitate low-dose CT imaging, we propose an improved statistical iterative reconstruction scheme based on the Penalized Weighted Least Squares (PWLS) standard combined with total variation (TV) minimization and sparse dictionary learning (DL) to improve reconstruction performance. We call this method "PWLS-TV-DL". In order to evaluate the PWLS-TV-DL method, we performed experiments on digital phantoms and physical phantoms, respectively. The experimental results show that our method is in image quality and calculation. The efficiency is superior to other methods, which confirms the potential of its low-dose CT imaging.
Keywords: Low dose computed tomography, penalized weighted least squares, total variation, dictionary learning.Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 197
1 Duration Analysis of New Firms in the Banking Industry
Authors: Jesus Orbe, Vicente Nunez-Anton
Abstract:
This paper studies the duration or survival time of commercial banks active in the Moscovian three month Rouble deposits market, during the 1994-1997 period. The privatization process of the Russian commercial banking industry, after the 1988 banking reform, caused a massive entry of new banks followed by a period of high rates of exit. As a consequence, many firms went bankrupt without refunding their deposits. Therefore, both for the banks and for the banks- depositors, it is of interest to analyze which are the significant characteristics that motivate the exit or the closing of the bank. We propose a different methodology based on penalized weighted least squares which represents a very general, flexible and innovative approach for this type of analysis. The more relevant results are that smaller banks exit sooner, banks that enter the market in the last part of the study have shorter durations. As expected, the more experienced banks have a longer duration in the market. In addition, the mean survival time is lower for banks which offer extreme interest rates. | https://publications.waset.org/search?q=%20penalized%20weighted%20least%20squares |
This last February I was the heaviest I have ever been, 185lbs (picture with the pink shirt). I decided at that point that is was time to make a change. Most of you know that I am pretty active but I needed some incentive. I decided to set a goal to do Scott Tinley’s Extreme Adventure triathlon at the end of the summer. This would be a good reason to start training. I got out the bicycles, started running and lifting weights pretty regularly. Over 2 months went by and I was running 15-20 miles a week and lifting weights at least 3-4 days and I had barely lost 10 lbs. (picture next to pink shirt pic is after 10lb loss) THEN I found Orange Coast Crossfit (see previous posts about the gym and stuff). I have written a lot about how awesome Crossfit is and my gym is so I won’t go way into that. After my first couple weeks of crossfit Justin asked me about my diet and talked to me about the Zone Diet. Of course he had already shown me so much and I really trusted him so I had no problem giving it a shot. Not to mention it kinda seemed like a challenge and I am all about the challenge, “Bring it on” (insert spirit fingers here).
I followed the diet exactly and the first week I felt great, a little hungry but good for the most part. But then the second week I thought I should have been committed to the mental ward! I was totally emotional and a space cadet! I went into the gym and told Justin that I was losing it. He told me about this other Crossfit girl who had the same issues and told me to push through it. I did make some minor adjustments that made life easier and the next week I was fine and living the Zone! I won’t go into details about the diet there is lots of info out there about it but I will tell you the biggest change for me was the carbohydrates. I originally decided to do the diet as much as I could Paleo Style (has a face, comes out of the ground or off a tree basically). I traded ALL my carbs for fruits and vegetables. AND I don’t eat Gluten (well barely). No Pasta, no rice :(, no bread :(:(. I don’t buy anything that comes in a box. I eat fruit 4-5 times a day, I eat cashews (because I hate almonds) 4-5 times a day (for my fat source), and I don’t have a cheat day. I found that when the cheat day came I didn’t want to cheat and/or I would crave my zone meal.
Did it work?? Minus the original 10 lbs I lost I have lost 20 lbs in 10 weeks for a total loss of 30 lbs since February. I am in great shape and feel amazing! I don’t have any clothes that fit me anymore but I don’t want to buy any because I continue to lose weight.
My goal weight is 145 and I am 10 lbs away. Losing weight and getting in shape is not easy but once you realize that being healthy isn’t “this short time of diet and training to get to your goal weight so you can return to your normal life” and start making it your lifestyle, you will see that its not that hard.
I look at these pictures and I feel really proud of myself and really excited because I know how much fun I am having and how seeing the results only motivates me more.
- so you know Im not a total health freak there are some things that I still eat to make myself happy-chocolate covered soy beans (have a couple a day), beer once and a while is good, I still eat sushi, and never feel guilty if I fall off the wagon, life is too short.
- my gym is the happiest place on earth because of the PEOPLE. All the people I work out with I know by name and I can tell you something special about all of them. AND they all care about my success as well as their own. In the 10 years I was a member at 24hour fitness I NEVER knew any ones name and had to practically beg people to even do so much as give me a spot!
- Two people that are very dear to me play a big role in my success, my trainers. Justin who is my crossfit “rock”- he puts his heart and soul in that gym and constantly teaches us more and more stuff. He takes pride in making each one of us better crossfitters. And somehow he finds time to improve himself so he is a great role model for those who are around him. Zac-who never lets me fail, and then when I am so disappointed in myself cause I could have done better he picks me up, brushes the dust off and tells me how awesome I did and how proud he is of me. Even when he is not there I hear his voice cheering me on. I couldn’t ask for a better support system.
So that’s my story and I am sticking to it! | https://thebyproduct.com/2009/08/06/thats-my-story-and-im-sticking-to-it/ |
Hydroinformatics offers a fresh perspective that is enabling communities around the world to tackle ageold problems in new ways and with a bigger toolset.
The water sector is in the throes of a bold transformation, driven by technology and smart water infrastructure. While advanced digital solutions have been leading the charge, there is a powerful, lesser-known force driving this disruption — hydroinformatics. Evolving from the early discipline of computational hydraulics, hydroinformatics is the application of information and decision support systems to address the equitable and efficient management of water.
Hydroinformatics engineers thrive from multidisciplinary perspectives, folding in expertise from traditional civil and environmental engineering, signal processing, machine learning, and control theory. Similar to computational hydraulics, hydroinformatics relies on the digital simulation of water flows and related processes but focuses on its application rather than the technology alone.
The Holistic Approach Of Hydroinformatics
Combining smart technologies with real-time data analytics and both physics- and non-physics-based models, hydroinformatics engineers work with clients to develop the next generation of sustainable, efficient, and autonomous water systems. As the industry continues to embrace digital solutions, water networks are becoming more and more instrumented. Therefore, the accurate and granular sensing of data is of fundamental importance to the application of digital systems in order to deliver high-quality results that inform better decision-making.
In a collaborative practice, hydroinformatics teams often work in conjunction with software developers to design solutions that optimize water and wastewater networks. Hydroinformatics engineers begin by analyzing a particular client’s challenges to come up with a highly configured algorithmic solution, such as a control strategy using existing assets, which can then be optimized with a genetic algorithm to work under an array of hydraulic conditions.
Optimization objectives can include (but are not limited to) adverse hydraulic conditions (such as flooding, overflows, high pressures), energy usage, and capital costs. Possible solutions are implemented, tested, and further refined with each iteration by hydroinformatics engineers to become solidified, before collaborating with software developers to bring a real-time decision support system into production.
The data collected, combined with the expertise to evaluate how these data correlate with a utility’s day-to-day operations, result in solutions that promote greater system visibility for early intervention. Such solutions are both sustainable and cost-effective, supporting long-term resiliency and capital planning.
Hydroinformatics In Action
Take smart network optimization systems, for example. Sewer overflows are a growing problem for many utilities in the U.S. and around the world, and with instances of severe weather on the rise due to climate change, utilities are challenged with managing them effectively in an affordable way. Xylem’s end-to-end wastewater optimization solution integrates directly into existing wastewater networks, using a combination of sensors and weather data, digital twin technology, and optimization algorithms to drastically reduce sewer overflows, minimize flooding events, and optimize functionality while maintaining regulatory compliance.
Serving a population of more than 850,000 people over 290 square miles, the Metropolitan Sewer District of Greater Cincinnati (MSD) operates combined and sanitary sewer systems, some of which were built more than a century ago. The systems were built to collect rainwater runoff, domestic sewage, and industrial wastewater in the same pipe. Whether by design or due to infiltration and inflow of stormwater they have a tendency to overflow, discharging an average of 14.4 billion gallons of combined sewage every year into the Ohio River and its tributary streams within Cincinnati’s urban watershed.
In 2002, the U.S. EPA entered into a federal consent decree with MSD, mandating the elimination of sanitary sewer overflows and significant mitigation of combined sewer overflows into receiving waterways. Engineers estimated the cost to mitigate the sewer overflows through capital investments at $3.1 billion, an unacceptable capital expense to pass along to MSD’s customers.
To overcome these challenges MSD partnered with Xylem to optimize the performance of their existing assets through advanced digital optimization solutions. Xylem worked with MSD to implement Xylem’s Wastewater Network Optimization solution that utilizes a combination of sensors and weather data to create a real-time decision support system (RT-DSS) that delivers automated, optimized control of existing assets to reduce sewage overflows while maximizing storage and treatment plant operations during wet weather.
After MSD implemented a coordinated real-time control (RTC) program, overflow volumes were reduced by 247 million gallons annually, representing a 45 percent reduction in overflow compared to the original design. Additionally, operational enhancements from the project increased treatment facility utilization by more than 100 percent, the result of more efficient use of existing assets.
Taking a similar approach, the City of Evansville in Indiana reduced its sewer overflows by more than 100 million gallons a year. Leveraging the same wastewater network optimization technology, the city effectively provided a software upgrade to its existing sewer system — allowing water managers to collect and analyze valuable data insights and convert the city’s existing network into infrastructure that is more resilient and affordable.
With real-time situational awareness of critical data points throughout the system, the city now has the visibility needed to allocate resources accordingly during instances of severe weather events.
Flow prediction dashboard from the City of Evansville
A New Future For Water Management
With challenges surrounding water availability, water quality, and water-related natural disasters set to increase in the near future, the time has come for utility managers to think smarter about water. This unique and relatively untapped discipline can transform utility operations by prescribing cost-effective and adaptive solutions that level the playing field and solve the world’s most complex water challenges.
With robust and high-resolution data and decision support forecasts coming online, the future of water network management will become capable of running a self-discovery of problems accompanied by recommendations to operators on the best mitigation strategies and respective outcomes. This will ultimately enhance resiliency in the face of unforeseen threats, decrease capital costs on infrastructure upgrades, and protect the environment to promote a sustainable and efficient approach to urban water management.
About The Author
Bryant E. McDonnell serves his team as the Senior Manager of Hydroinformatics and Process Control for Xylem. He is a Professional Engineer (OH, KY, NE, MO) and has degrees in civil and environmental engineering from Southern Illinois University Carbondale and the University of Cincinnati. He is an autodidactic analytical software programmer and has been working in the hydroinformatics space for over 10 years. He was the original author behind OpenWaterAnalytics-PySWMM (Python Programming Interface to Stormwater Management Model) open-source software library. He is passionate about solving old problems in new ways to save money for public utilities and their ratepayers. | https://www.wateronline.com/doc/hydroinformatics-intro-to-water-optimization-and-efficiency-0001 |
BACKGROUND
DETAILED DESCRIPTION
An extended graph topology comprising explicit graph edges can be processed by systems comprising tools, libraries and frameworks. These systems processing the graph topology may rely on the explicit graph edges to obtain answers to queries.
The desire for computers to give direct answers to human questions has proven a popular field of research for many years. Techniques can be used to create query answering (QA) systems to give direct answers to human questions or queries. In this particular field, the use of graphs has also proven popular. Existing systems may rely either on graph databases with complete knowledge, or on unstructured systems that require specialized technology for analysis. A QA system is any system or method that produces answers to queries and may associate those answers with confidences indicating the likelihood the answers can be correct, and that may associate answers with a passage-based justification that are intended to explain to humans why the answer is likely correct. A system that gives direct answers to human questions using graph topologies by interrogating the graph may rely on explicit elements of the graph topology, such as explicit graph edges to provide an answer to a query. In these cases, if an element of the graph is missed, a (human) question queried to the system may not be answered as the query of the graph topology may be incomplete due to missed parts of the graph topology (e.g., where explicit graph edges do not link to the missed parts).
A query may be defined as a single sentence or phrase in natural language (e.g., English) or a formal language (e.g., First order logic) that may intend to ask for the end point(s) of a relation or to ask whether or not a relation between two concepts can be true. A relation may be a named association between two concepts. General examples of relations include: A “indicates” B, A “causes” B, A “treats” B, A “activates” B, and A “discovered” B. The concepts can be considered the “arguments” or “end points” of the relation. An answer or solution can be an element of text: a word, number, phrase, sentence, passage or document. An actual answer is thought to be correct or partially correct with respect to a query if a human considers it useful response to the query. Thus, an actual answer may be provided by a user or otherwise determined by a QA system. In the case of a simple query or relation, the answer is typically the sought-after end-point of the relation.
The present disclosure proposes a solution applied for a QA system which may provide strong guessing capabilities responsive to querying a graph topology as a knowledge base. The QA system can provide a most-likely answer (e.g., with a highest likelihood score) to a query related to an actual answer, and node grouping patterns can be used to perform edge inference among unconnected nodes within the patterns in the graph topology. As an illustrative example, the QA system proposed in the present disclosure may imitate human thinking to find a most likely answer to a question such as a question asking: “How many legs does a Pomeranian have?”. If the human is unaware that a Pomeranian is a dog, then he could resort to other information to arrive at the most likely answer. Perhaps the human could see an advertisement at a pet store offering “White Pomeranians for sale”, or he may know that a friend had bought one for her elderly mother. He could thus make a strong guess that the Pomeranians have four legs as the most likely answer, even if he can't be 100% certain.
The QA system proposed in the present disclosure can implement natural language processing (NLP) through machine learning techniques, for example, in order to answer questions posed by humans in a natural language. Some major tasks in NLP that can be implemented by the proposed QA system can include, e.g., morphological segmentation, named entity recognition (NER), natural language generation and understanding, optical character recognition, relationship extraction, sentence breaking, speech recognition and processing, word segmentation, information retrieval IR, etc.
The structured database of knowledge of information, e.g. the knowledge base described herein, can be a graph topology. A graph topology or inference graph can be any graph represented by a set of nodes connected by edges, where the nodes can represent statements and the edges or arcs can represent relations between statements. Each relation may be associated with a confidence, and each concept in a relation may be associated with a confidence. Each edge can be associated with a set of passages providing a justification for why that relation may be true. Each passage justifying an edge may be associated with a confidence indicating how likely the passage justifies the relation. An inference graph can be used to represent relation paths between factors in an inquiry and possible answer to that inquiry. An inference graph is multi-step if it contains more than one edge in a path from a set of factors to an answer.
In an example according to the present disclosure, a query answering system to query a graph topology includes a physical processor and a non-transitory memory storing machine-readable instructions. The machine-readable instructions, when executed, can cause the processor to obtain a query provided by a user to query the graph topology, where an actual answer to the query may be unknown from the graph topology and to query a set of nodes and a set of edges in the graph topology associated with the obtained query. In this respect, querying the set of nodes and edges can comprise applying neighboring graph structure statistics to the set of nodes and edges to obtain a set of node grouping patterns and where each of the node grouping patterns can comprise an associated score within the graph topology. Furthermore, the machine-readable instructions, when executed, can cause the processor to identify a set of unconnected nodes within the obtained set of patterns based on the associated score, infer one or more edges to link the set of unconnected nodes based on machine learning and feedback techniques and provide a most-likely answer to the query based on the linking of the set of unconnected nodes.
In another example according to the present disclosure, a method can be implemented or performed by a query answering system including a physical processor executing machine readable instructions. The method may include obtaining a query provided by a user to query the graph topology. An actual answer to the query is unknown from the graph topology. The method may further comprise querying a set of nodes and a set of edges in the graph topology associated with the obtained query, where querying the set of nodes and edges comprises applying neighboring graph structure statistics to the set of nodes and edges to obtain a set of node grouping patterns and where each of the node grouping patterns comprises an associated score within the graph topology. The method may comprise identifying a set of unconnected nodes within the obtained set of patterns based on the associated score, inferring one or more edges to link the set of unconnected nodes based on machine learning and feedback techniques, obtaining a set of likely answers to the query ranked by likelihood based on the linking of the set of unconnected nodes and providing a likely answer from the set based on a highest likelihood score.
In another example according to the present disclosure, a non-transitory machine-readable storage medium may be encoded with instructions to query a graph topology. The non-transitory machine-readable storage medium may comprise instructions to obtain a query provided by a user to query the graph topology. An actual answer to the query is unknown from the graph topology. The non-transitory machine-readable storage medium may comprise instructions to query a set of nodes and a set of edges in the graph topology associated with the obtained query, where querying the set of nodes and edges comprises applying neighboring graph structure statistics to the set of nodes and edges to obtain a set of node grouping patterns and where each of the node grouping patterns comprises an associated score within the graph topology. The non-transitory machine-readable storage medium may comprise instructions to identify a set of unconnected nodes within the obtained set of patterns based on the associated score, infer one or more edges to link the set of unconnected nodes based on neural networks, obtain a set of likely answers to the query ranked by likelihood based on the linking of the set of unconnected nodes and provide a likely answer from the set based on a highest likelihood score.
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Referring now to the drawings, shows an example of a query answering system to query a graph topology. The query answering system may be, for example, a cloud server, a local area network server, a web server, a mainframe, a mobile query answering system, a notebook or desktop computer, a smart TV, a point-of-sale device, a wearable device, any other suitable electronic device, or a combination of devices, such as ones connected by a cloud or internet network, that perform the functions described herein. In the example shown in , the query answering system includes a processing resource and a non-transitory machine-readable storage medium encoded with instructions to query a graph topology.
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The processing resource may be one or more central processing units (CPUs), semiconductor-based microprocessors, and/or other hardware devices suitable for retrieval and execution of instructions stored in a machine-readable storage medium . The processing resource may fetch, decode, and execute instructions , , , and and/or other instructions to implement the procedures described herein. As an alternative or in addition to retrieving and executing instructions, the processing resource may include one or more electronic circuits that include electronic components for performing the functionality of one or more of instructions , , , and .
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In an example, the program instructions , , , and , and/or other instructions can be part of an installation package that can be executed by the processing resource to implement the functionality described herein. In such a case, the machine-readable storage medium may be a portable medium such as a CD, DVD, or flash drive or a memory maintained by a query answering system from which the installation package can be downloaded and installed. In another example, the program instructions may be part of an application or applications already installed on the query answering system .
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The machine-readable storage medium may be any electronic, magnetic, optical, or other physical storage device that contains or stores executable data accessible to the query answering system . Thus, the machine-readable storage medium may be, for example, a Random Access Memory (RAM), an Electrically Erasable Programmable Read-Only Memory (EEPROM), a storage device, an optical disc, and the like. The machine-readable storage medium may be a non-transitory storage medium, where the term “non-transitory” does not encompass transitory propagating signals. The machine-readable storage medium may be located in the query answering system and/or in another device in communication with the query answering system .
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As described in detail below, the machine-readable storage medium may be encoded with instructions to obtain a query provided by a user to query the graph topology. An actual answer to the query may be unknown from the graph topology but known by the user providing the query. Instructions can query a set of nodes and a set of edges in the graph topology associated with the obtained query. Querying the set of nodes and the set of edges may comprise applying neighboring graph structure statistics to the set of nodes and edges to obtain a set of node grouping patterns upon execution of instructions . In this respect, each of the node grouping patterns can comprise an associated score within the graph topology. Instructions can identify a set of unconnected nodes within the obtained set of patterns based on the associated score of the node grouping patterns. Furthermore, instructions can infer one or more edges to link the set of unconnected nodes based on machine learning and feedback techniques and instructions can provide a most-likely answer to the query based on the linking of the set of unconnected nodes.
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shows a query answering (QA) system to query a graph topology according to another example of the present disclosure. The QA system may comprise a processing resource and a machine-readable storage medium comprising (e.g., storing) instructions to query a graph topology. Furthermore, the QA system comprises a display and input-output equipment . Examples of input-output equipment can comprise a keyboard, microphone, webcam, connectors, etc.
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The machine-readable storage medium can comprise instructions to obtain a query provided by a user to query the graph topology. Instructions may cause the QA system to identify a set of nodes and a set of edges within the graph topology associated with the query by parsing the query. In an example, instructions may perform NLP as e.g. information retrieval IR and text recognition in order to parse the query and identify a set of nodes and edges associated with the query. In an example according to the present disclosure the query may be e.g., ASCII characters, files as text documents, images, audio, mind maps, videos, etc.
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In an example, the instructions to obtain a query provided by a user to query the graph topology can comprise instructions to present a blank record in the display that may permit the user to specify the query by means of a keyboard comprised within the I/O equipment . In another example, instructions to obtain a query provided by a user to query the graph topology can comprise instructions to obtain the query according to voice recognition via a voice sensor as e.g. a microphone comprised in the I/O equipment .
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The machine-readable storage medium can comprise instructions to query a set of nodes and a set of edges in the graph topology associated with the obtained query, which may cause the QA system to query the set of nodes and edges by applying neighboring graph structure statistics to the set of nodes and edges to obtain a set of node grouping patterns. In this respect, the present solution can take use of the obtained set of node grouping patterns within the graph topology itself to infer related edges within the graph topology in order to obtain a most-likely answer to the query.
In an example, the neighboring graph structure statistics use a nearest neighbor search (NNS) for finding the most likely nodes based on the query and data mining processing for graph databases as, e.g., sequential pattern mining in order to discover patterns in the graph topology from a macroscopic graph analysis. The NNS applied in the present disclosure can be defined as an optimization problem for finding the most similar nodes in the graph topology having as starting points the nodes and edges extracted from the query. In an example, the associated score can be a likelihood score based on the actual answer. The likelihood score can be, e.g., a percentage value or an integer or it can be a number of edge hops between nodes associated with the query and the actual answer.
In another example, statistical measures as, e.g., the covariance or the mean of node properties can be obtained in order to find related likely nodes within the graph topology to the nodes from the set of nodes associated with the query based on the aforementioned statistical measures and include the found nodes into one or more node grouping patterns. Node grouping patterns may be redefined based on statistics results and likelihood optimization.
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In another example, responsive to having a graph topology having one edge with no attributes linking two nodes, the statistics used may comprise deciding whether there's a link or not, if there is a link from where it may come from and counting of other links. As an analogy of this type of graph to the human brain, the statistics can work by deciding whether there are links between neurons or not. Hence, this measure can become hugely powerful when the large number of links work all together from a macrocospic perspective of the brain. This analogy can apply to graph topologies that can be used by the QA system , the QA system , or any other system implementing the features disclosed herein.
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The machine-readable storage medium can comprise instructions to identify a set of unconnected nodes within the obtained set of node grouping patterns. Instructions may take use of the associated likelihood scores in the node grouping patterns. Hence, the most likely unconnected nodes in a node grouping pattern may identified based on statistics for performing edge inference.
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The machine-readable storage medium can comprise instructions to infer one or more edges to link the set of identified unconnected nodes from the set of node grouping patterns based on machine learning and feedback techniques. An example of machine learning techniques can be, e.g., neural networks applied for edge inference. The inference of one or more edges may provide one or more new paths, e.g, the one or more new paths in the graph topology may comprise previously-unconnected nodes from the set of node grouping patterns now linked based on edge inference. Hence, instructions may permit the graph to connect or link the set of nodes associated with the obtained query in order to arrive at a most-likely answer representing the actual answer over one or more paths having one or more edges representing relations between the query and the actual answer. These one or more paths may represent one or more solutions in the graph to the actual answer and these one or more paths may have an associated likelihood score.
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The machine-readable storage medium can comprise instructions to provide a set of likely answers according to the query, and this set of likely answers may be ranked by likelihood. Instructions may select a most-likely answer to the query based on the linking of the set of unconnected nodes. The one or more paths may represent one or more solutions in the graph to the actual answer and they may be classified based on an associated likelihood score. Hence, instructions my select the most-likely answer associated with a path with a highest likelihood score obtained by executing instructions . In an example according to the present disclosure, the most-likely answer may be equal to the actual answer that can be known by the user. Hence, the likelihood score of the most-likely answer can be, e.g., 100%.
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The machine-readable storage medium can comprise instructions to verify the most-likely answer based on human feedback. Human feedback may be obtained by means of the I/O equipment . The human feedback representing the actual answer once processed by the QA system may be analyzed and compared against the most-likely answer obtained by the QA system .
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In an example, the machine-readable storage medium may be encoded with instructions to provide a likelihood score associated with the most-likely answer. This provided likelihood score may be the highest likelihood score obtained by the QA system . The likelihood score associated with the most-likely answer may be displayed in the display .
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In an example, the machine-readable storage medium may be encoded with instructions to query the graph topology and obtain a set of node grouping patterns that comprise instructions to apply community detection algorithms to node properties of the graph topology associated with the obtained query and wherein these nodes may contain information about people. Different communities can be represented as different nodes in the graph. This algorithm may apply a filter that may be useful in the cases when a different mapping of information is needed. Some examples of community filtering may be to access the information filtered per period, location or gender.
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In another example, the machine-readable storage medium may be encoded with instructions to query the graph topology and obtain a set of node grouping patterns that comprise instructions to apply a decay function on timestamped data associated with the graph, e.g. some existing timestamp relationships in the graph could be ignored in the graph if they happen to be very old. This function may apply a filter that may be useful in the cases where the old data may not be relevant anymore.
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In another example, the machine-readable storage medium may be encoded with instructions to query the graph topology and obtain a set of node grouping patterns that comprise instructions to apply a triadric closure (e.g. transitivity) to measure the strength of the connection of data among nodes. Triadic closure is the property among three nodes A, B, and C, such that if a strong tie exists between A-B and A-C, there is a weak or strong tie between B-C. It can be a method commonly used in social networks to identify further connections between its users.
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Turning now to , this figure shows a flowchart of an example process implemented by a query answering QA system for querying a graph topology. The process comprises block for obtaining a query provided by a user to query a graph topology upon executing instructions or . In block a set of nodes and a set of edges within the graph topology associated with the query may be identified by parsing the query. In an example, in block NLP as, e.g., information retrieval IR and text recognition may be performed in order to parse the query and identify a set of nodes and edges associated with the query. In an example according to the present disclosure, the query may be e.g., ASCII characters, files as text documents, images, audio, mind maps, videos, etc.
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The process further comprises block for querying a set of nodes and edges in the graph associated with the query upon executing instructions or . Neighboring graph structure statistics may be applied in block in order to obtain a set of node grouping patterns where each of the node grouping patterns can comprise an associated score within the graph topology. In one example, neighboring graph structure statistics can take use of nearest neighbor search NNS for finding the most likely nodes based on the query and data mining processing for graph databases as e.g. sequential pattern mining in order to discover patterns in the graph topology from a macroscopic graph analysis. In another example, statistical measures as, e.g., the covariance or the mean of node properties can be obtained in order to find related likely nodes within the graph topology to the nodes associated with the query based on the aforementioned statistical measures and identify the found nodes into one or more node grouping patterns. Node grouping patterns may be redefined based on statistics results and likelihood optimization. In another example, responsive to having a graph topology having one edge with no attributes linking two nodes, the statics used may comprise deciding whether there's a link or not, who may be from and counting of other links.
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The process further comprises block for identifying a set of unconnected nodes within the obtained set of node grouping patterns based on the associated score upon executing instructions or . The most likely unconnected nodes in a node grouping pattern may identified based on statistics for performing edge inference. In another example, one or more unconnected nodes having a similar associated likelihood score may be identified. Block may take use of the associated likelihood scores in the node grouping patterns. The likelihood score can be e.g. a percentage value or an integer or it can be a number of edge hops between nodes associated with the query and the actual answer.
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The process further comprises block for inferring one or more edges to link the set of unconnected nodes based on machine learning and feedback techniques upon executing instructions or . An example of machine learning techniques can be, e.g., neural networks applied for edge inference. The inference of one or more edges may provide one or more new paths based on the graph topology, e.g. the one or more new paths in the graph topology may comprise previously-unconnected nodes from the set of node grouping patterns now linked based on edge inference. Hence, block upon executing instructions or may permit the graph to connect or link the set of nodes associated with the obtained query in order to obtain a most-likely answer representing the actual answer that may be known by the user over one or more paths having one or more edges representing relations between the query and the actual answer. These one or more paths may represent one or more solutions in the graph to the actual answer and these one or more paths may have an associated likelihood score.
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The process further comprises block for obtaining a set of likely answers to the query ranked by likelihood based on the linking of the set of unconnected nodes upon executing instructions . Block may select a most-likely answer to the query based on the linking of the set of unconnected nodes previously performed in block . The one or more paths obtained in block may represent one or more solutions in the graph to the actual answer and they may be classified based on an associated likelihood score. Hence, block may select the most-likely answer associated with a path with a highest likelihood score. In an example according to the present disclosure, the most-likely answer may be equal to the actual answer that can be known by the user. Hence, the likelihood score of the most-likely answer can be e.g. 100%.
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The process further comprises block for providing a likely answer from the set based on a highest likelihood score upon executing instructions . One of the likely answers may be identified as the most-likely answer responsive to having the highest likelihood score. In an example, the likelihood score of the most-likely answer, i.e. the most-likely answer can be provided to the user.
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In another example, the process may comprise a block for presenting a blank record on a display that may permit the user to specify the query by means of a keyboard. In another example, the process may comprise a block to obtain the query according to voice recognition via a voice sensor as e.g, a microphone.
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In another example, the process may comprise a block for verifying whether the most-likely answer is the actual answer based on human feedback. Human feedback representing the actual answer once processed by the QA system performing the process may be analyzed and compared against the most-likely answer obtained under block .
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Turning now to . shows a block diagram of an example non-transitory machine-readable storage medium . The non-transitory machine-readable medium may include instructions executed in a query answering QA system as the examples shown in and . The non-transitory machine-readable medium can store machine-readable instructions executable by a processing resource . The non-transitory machine-readable medium can comprise instructions to obtain a query provided by a user to query the graph topology. The actual answer to the query can be unknown from the graph topology.
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The non-transitory machine-readable medium can comprise instructions to query a set of nodes and a set of edges in the graph topology associated with the obtained query. Querying the set of nodes and edges can comprise applying neighboring graph structure statistics to the set of nodes and edges to obtain a set of node grouping patterns. Furthermore each of the node grouping patterns can comprise an associated score within the graph topology. Neighboring graph structure statistics may be applied by executing instructions in order to obtain a set of node grouping patterns where each of the node grouping patterns can comprise an associated score within the graph topology.
In one example, neighboring graph structure statistics can take use of nearest neighbor search NNS for finding the most likely nodes based on the query and data mining processing for graph databases as e.g. sequential pattern mining. In another example, statistical measures as e.g. the covariance or the mean of node properties can be obtained. Hence, node grouping patterns may be redefined based on statistics results and likelihood optimization. In another example, responsive to having a graph topology having one edge with no attributes linking two nodes, the statics used may comprise deciding whether there's a link or not, who may be from and counting of other links.
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The non-transitory machine-readable medium can comprise instructions to identify a set of unconnected nodes within the obtained set of patterns based on the associated score. In one example, instructions can comprise instructions to identify a set of unconnected nodes having a similar associated score. The most likely unconnected nodes in a node grouping pattern may identified based on statistics for performing edge inference. In another example, one or more unconnected nodes having a similar associated likelihood score may be identified. The instructions may take use of the associated likelihood scores in the node grouping patterns.
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The non-transitory machine-readable medium can comprise instructions to infer one or more edges to link the set of unconnected nodes based on neural networks. The inference of one or more edges may provide one or more new paths based on the graph topology, e.g. the one or more new paths in the graph topology may comprise previously-unconnected nodes from the set of node grouping patterns now linked based on edge inference. Instructions may permit to link unconnected nodes associated with the obtained query in order to obtain a most-likely answer representing the actual answer over one or more paths having one or more edges representing relations between the query and the actual answer. These one or more paths may represent one or more solutions in the graph to the actual answer and these one or more paths may have an associated likelihood score.
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The non-transitory machine-readable medium can comprise instructions to obtain a set of likely answers to the query ranked by likelihood based on the linking of the set of unconnected nodes. Instructions may select a most-likely answer to the query based on the linking of the set of unconnected nodes previously performed by instructions . The one or more paths obtained by instructions may represent one or more solutions in the graph to the actual answer and they may be classified based an associated likelihood score. The likelihood score can be e.g. a percentage value or an integer or it can be a number of edge hops between nodes associated with the query and the actual answer.
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The non-transitory machine-readable medium can comprise instructions to provide a likely answer from the set based on a highest likelihood score. Hence, instructions may select the most-likely answer associated with a path with a highest likelihood score. In an example according to the present disclosure, the most-likely answer may be equal to the actual answer that can be known by the user. Hence, the likelihood score of the most-likely answer can be e.g. 100%.
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The non-transitory machine-readable medium can further comprise machine-readable instructions to verify whether the most-likely answer is the actual answer based on human feedback. The human feedback representing the actual answer can be processed and compared against the most-likely answer obtained by the QA system comprising the machine-readable medium .
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The non-transitory machine-readable medium can further comprise machine-readable instructions to provide the highest likelihood score of the most-likely answer. One of the likely answers may be identified as the most-likely answer responsive to having the highest likelihood score. The likelihood score of the most-likely answer, i.e. the most-likely answer can be provided to the user, as e.g. displaying the most-likely answer in a display.
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The sequence of operations described in connection with are examples and are not intended to be limiting. Additional or fewer operations or combinations of operations may be used or may vary without departing from the scope of the disclosed examples. Furthermore, implementations consistent with the disclosed examples may not perform the sequence of operations or instructions in any particular order. Thus, the present disclosure merely sets forth possible examples of implementations, and many variations and modifications may be made to the described examples. All such modifications and variations are intended to be included within the scope of this disclosure and protected by the following claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a block diagram of an example query answering system for querying a graph topology.
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is a block diagram of another example query answering system for querying a graph topology.
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is a flowchart of an example process for querying a graph topology.
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is a block diagram of an example machine-readable storage medium including instructions to query a graph topology. | |
Tomato Basil Bruschetta is such a classic Italian appetizer, and something everyone should make when tomatoes are at their peak. This version is completely authentic with just tomatoes, basil, olive oil, and a little bit of salt and pepper to season the tomatoes. It's served with crusty Italian bread, and that's it.
Preheat oven to 350 degrees.
Use a sharp knife to cut bread into 3/4-inch slices. Cut in half so each piece is about 3-4 inches long. Using a pastry brush, brush bread with 1 1/2 tablespoons olive oil. It doesn't need to be saturated in oil, just damp enough for the salt and pepper to ahere. Season with salt and pepper. Line up on baking sheet. Toast unitl LIGHTLY toasted, about 4-5 minutes. Cool completely.
While the bread toasts, add tomatoes, garlic, salt, basil, and remaining 2 teaspoons olive oil to a small bowl. Mix to combine. Let sit for about 15 minutes.
Serve toasted bread with bruschetta topping. | https://www.cookingforkeeps.com/wprm_print/recipe/22305/ |
TECHNICAL FIELD
This invention relates to a cam motor apparatus used as a motor for traveling a construction machine or a motor for other purposes, and specifically relates to a cam motor apparatus configured such that the motor capacity is changed between large and small stages so that the rotation is changed between a low-speed mode rotating at low speed and a high-speed mode rotating at a speed higher than that in the low-speed mode.
BACKGROUND ART
As a cam motor apparatus of such kind, there is known a conventional cam motor apparatus configured such that a plurality of pistons and cylinders are divided into four groups and the condition of distribution of working oil to the pistons and cylinders included in each group is changed between two stages through the operation of a selector valve (See, for example, FIG. 2 in Japanese Patent Application Laid-Open Gazette No. 55-153871). In this motor, when the selector valve is changed to a low- speed mode, working oil is supplied to each cylinder included in two groups selected from among the four groups, whereas each cylinder included in the other two groups is connected to an oil tank so as to discharge working oil thereto. Thereby, the motor capacity of the cam motor apparatus becomes a maximum value so that the motor is rotated at relatively low speed and high output torque.
On the other hand, when the selector valve is changed to a high- speed mode, working oil is supplied to each cylinder included in one of the selected two groups, working oil is discharged from each cylinder included in one of the other two groups, and cylinders included in the remaining two groups are connected to each other to form a closed circuit. Thereby, the motor capacity becomes half the value in the low- speed mode so that high-speed rotation is made at a speed approximately twice as fast as the low-speed mode.
In the conventional cam motor apparatus above-described, however, since each cylinder included in the two groups in which neither oil supply nor oil discharge is made in the high-speed mode has a closed circuit, no escape route is left for pressurized oil in the cylinder so that large resistance to the motor rotation may be produced. To cope with this, it can be considered that each cylinder included in the above- mentioned two groups is communicated with the oil tank. In this case, however, the oil pressure of each cylinder included in the two groups becomes close to the atmospheric pressure so that slide contact between the piston and the cam surface in the cylinder cannot be held by the oil pressure. As a result, undesirable beat sounds are produced due to collision between the piston and the cam surface, and the piston and the cam surface are decreased in durability.
To eliminate the above problems, it is necessary to dispose a spring between the piston and the bottom surface of the cylinder room as in the conventional cam motor apparatus so as to press the piston against the cam surface by the spring. In this case, however, the component count of the apparatus is increased. This increases the weight of the apparatus and complicates the structure thereby involving much expense in time and effort for assembly.
In view of the foregoing problems, the present invention has been made. Therefore, an object of the present invention is to hold slide contact between the piston and the cam surface thereby increasing silentness and durability and to decrease component count thereby reducing weight and increasing ease of assembly.
DISCLOSURE OF THE INVENTION
To attain the above object, in the present invention, pressurized oil is supplied from a charging pump, provided for supplying working oil to the working oil supply system of the cam motor apparatus so as to cope with leakage of the working oil, to the piston which falls into a state that no driving force is produced in a high-speed mode. As a result, slide contact between the piston and the cam surface can be held.
More specifically, as shown in FIGS. 1 and 2, the present invention premises a cam motor apparatus comprising: a cylindrical cylinder block (2); a cam ring (3) having a cam surface (3a) formed in the inner periphery thereof and disposed surrounding the outer periphery of the cylinder block (2); a plurality of cylinders (5, 5, . . . ) radially formed in the cylinder block (2) to extend radially outward around the central axis (X) of the cylinder block (2) and to be open in the outer periphery of the cylinder block (2); pistons (6) respectively housed in the cylinders (5) in a manner to extend to and retract from the cam surface (3a); and a distribution valve (7), coupled to an end surface (2a) of the cylinder block (2) in a manner to be rotatable relative to the cylinder block (2), for distributing working oil, supplied from a working oil supply system (150), to the cylinders (5) corresponding to the pistons (6) in an ascending cycle of ascending toward the cam surface (3a) out of the plurality of cylinders (5, 5, . . . ), wherein the pistons (6) in the ascending cycle press the cam surface (3a) so that one of the cylinder block (2) and the cam ring (3) the other of which is fixed in a non-rotating state rotates relative to the other.
The cam motor apparatus having the above structure further comprises: four communication passages (8a, 8b, 8c, 8d) for supplying working oil to the plurality of cylinders (5, 5, . . . ) divided into four groups in a manner to distribute the working oil among the four groups; and a selector valve (9) for selectively connecting the four communication passages (8a, 8b, 8c, 8d) to an oil supply side or an oil discharge side of the working oil supply system (150) to change the rotation of the cylinder block (2) or the cam ring (3) between a low- speed mode and a high-speed mode.
Further, the cylinder block (2) is provided with distributed- side ports (21, 21, . . . ) which are communicated with the respective cylinders (5, 5, . . . ) and are open at the end surface (2a) at uniform intervals on a circumference around the central axis (X). The distribution valve (7) is provided at an end surface (7a) coupled to the cylinder block (2) with distribution ports (71, . . . , 72, . . . , 73, . . . , 74, . . . ) a count of which is an integral multiple of 4 and which are formed to be open at uniform intervals on the same circumference as the distributed-side ports (21, 21, . . . ) are located, the distribution ports (71, . . . , 72, . . . , 73, . . . , 74, . . . ) being divided into four distribution port groups having the same port count, the distribution ports being each communicated at an end thereof with one of the four communication passages (8a, 8b, 8c, 8d) in units of the distribution port groups.
The selector valve (9) includes: a low rotational speed position that connects two passages (8c, 8d or 8a, 8b), selected from among the four communication passages (8a, 8b, 8c, 8d), to the oil supply side of the working oil supply system (150) and connects the other two passages (8a, 8b, or 8c, 8d) to the oil discharge side of the working oil supply system (150); and a high rotational speed position that connects one (8c or 8a) of the selected two passages to the oil supply side, connects one (8a or 8c) of the other two passages to the oil discharge side and connects the remaining two passages (8d, 8b) to a delivery side of a charging pump (16) for supplying charging oil to the oil discharge side of the working oil supply system (150).
Under the above configuration, when the selector valve (9) is in the low rotational speed position, two passages (8c, 8dor 8a, 8b) selected from among the four passages are connected to the oil supply side of the working oil supply system (150) and the other two passages (8a, 8b or 8c, 8d) are connected to the oil discharge side of the working oil supply system (150). Thereby, working oil is supplied from the selected two passages (8c, 8dor 8a, 8b) to the cylinders (5) in which the pistons (6) are in the ascending cycle of ascending toward the cam surface (3a) through the distribution ports (71, . . . , 73, . . . or 72, . . . , 74, . . . ) and the distributed-side ports (21, 21, . . . ). The pistons (6) housed in the cylinders (5) press the cam surface (3a) so that one of the cylinder block (2) and the cam ring (3) rotates relative to the other. Working oil is discharged from the cylinders (5) in which the pistons (6) are in a descending cycle of descending toward the rotational axis (X), passes through the distributed-side ports (21, 21, . . . ) and the distribution ports (72, . . . , 74, . . . or 71, . . . , 73, . . . ) and is returned to the oil discharge side of the working oil supply system (150) through the non-selected two passages (8c, 8b or 8c, 8d). As a result, the cam motor apparatus obtains a maximum motor capacity to rotate in the low-speed mode where the speed is relatively low and the output torque is relatively high.
On the other hand , when the selector valve (9) is in the high rotational speed position, one (8c or 8a) of the selected two passages (8c, 8dor 8a, 8b) is connected to the oil supply side of the working oil supply system (150), one (8a or 8c) of the other two passages (8a, 8b or 8c, 8d) is connected to the oil discharge side of the working oil supply system (150), and the remaining two passages (8d, 8b) are connected to the delivery side of the charging pump (16) for supplying charging oil to the oil discharge side of the working oil supply system (150). Thereby, the pistons (6, 6, . . . ) supplied with high-pressure working oil are reduced to half the count in the low-speed mode. As a result, the motor capacity of the cam motor apparatus is reduced in half so that the motor apparatus is rotated in the high-speed mode having approximately double the speed and half the output torque in the low- speed mode.
At the time, the pressures in the cylinders (5) connected to the delivery side of the charging pump (16) are held at the same pressure as in the oil discharge side of the working oil supply system (150) through the supply of pressurized oil from the charging pump (16). Thereby, slide contact between the piston (6) in each of the cylinders (5) and the cam surface (3a) can be held without producing large rotational resistance. As a result, collision between the piston (6) and the cam surface (3a) can be prevented. This increases silentness and durability. Further, since there is no need for providing a spring for pressing the pistons (6, 6, . . . ) against the cam surface (3a), the component count of the apparatus can be decreased as compared with the prior art. This reduces the weight of the entire apparatus and increases ease of assembly.
As shown in FIG. 1, the cam motor apparatus described above can be configured such that the cam ring (3) is fixed in a non-rotating state to a body (13) of the cam motor apparatus and the cylinder block (2) is rotatably supported to the body (13).
According to this configuration, when the cylinder block (2) is rotated relative to the cam ring (3) fixed in a non-rotating state to the body (13) of the cam motor apparatus, the cam motor apparatus can supply a rotational driving force with reliability.
Further, under the above configuration, as shown in FIGS. 1, 4 and 5, the selector valve (9) can be configured to be changeable between the low rotational speed position and the high rotational speed position by pressurized oil supplied from the charging pump (16).
According to this configuration, the selector valve (9) operates through the supply of pressurized oil from the charging pump (16) for supplying charging oil to the oil discharge side of the working oil supply system (150). Accordingly, there is no need for providing any special driving source for operating the selector valve (9). This achieves cost reduction and compaction of the entire apparatus.
Furthermore, under the above configuration, as shown in FIGS. 4 and 5, the selector valve (9) can include a valve element (92) formed in a column and a charge pressure supply passage (926) formed in the valve element (92) and communicated through one end thereof with the charging pump (16), and can be configured such that the other end of the charge pressure supply passage (926) is open to the two communication passages (8d, 8b) connected to neither the oil supply side nor the oil discharge side of the working oil supply system (150) when the selector valve (9) is in the high rotational speed position.
According to this configuration, charging oil from the charging pump (16) is supplied to the two communication passages (8d, 8b) connected to neither the oil supply side nor the oil discharge side of the working oil supply system (150), through the charge pressure supply passage (926) formed in the valve element (92) of the selector valve (9). Thus, since the charge pressure supply passage (926) is formed in the valve element (92) of the selector valve (9), an oil pressure circuit for supplying charge pressure can be compacted. This compacts the entire apparatus.
Further, under the above configuration, as shown in FIG. 1, the working oil supply system (150) can be configured such that the oil supply side and the oil discharge side are reversible.
According to this configuration, by reversing the oil supply side and the oil discharge side of the working oil supply system (150) each other, the cam motor apparatus can be changed between a normal rotation and a reverse rotation. In the case of the reverse rotation as well as the case of the normal rotation, when the selector valve (9) is in the low rotational speed position, the cam motor apparatus obtains a maximum motor capacity so as to be rotated in the low-speed mode having relatively low speed and high output torque. On the other hand, when the selector valve (9) is in the high rotational speed position, the motor capacity of the cam motor apparatus is reduced in half so that the cam motor apparatus is rotated in the high-speed mode having approximately double the speed and half the output torque in the low-speed mode.
At the time, when the selector valve (9) is in the high rotational speed position, as in the case of the normal rotation, the two passages (8d, 8b) connected to neither the oil supply side nor the oil discharge side of the working oil supply system (150) are connected to the delivery side of the charging pump (16). Thereby, the pressures in the cylinders (5), supplied with pressurized oil from the charging pump (16) through the two passages (8d, 8b), are held at the same pressure as in the oil discharge side of the working oil supply system (150). Accordingly, slide contact between the piston (6) in each of the cylinders (5) and the cam surface (3a) can be held without producing large rotational resistance. As a result, also in the reverse rotation, silentness and durability in the high-speed mode can be increased.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partly cutaway view of an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken on line A--A of FIG. 1.
FIG. 3 is a perspective view showing the arrangement of distribution ports.
FIG. 4 is an enlarged sectional view showing the structure of a supply/discharge operating valve.
FIG. 5 is a diagram of the supply/discharge operating valve in a high rotational speed position, which corresponds to FIG. 4.
FIG. 6 is a diagram showing an exemplified structure of a supply/discharge operating valve in a conventional cam motor apparatus.
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments for carrying out the invention will be described with reference to the drawings.
FIG. 1 shows a cam motor apparatus A according to an embodiment of the present invention. In FIG. 1, a reference numeral 1 denotes an annularly shaped casing body, a reference numeral 2 denotes a cylinder block formed in a cylinder having a heavy wall thickness, a reference numeral 3 denotes a cam ring disposed so as to surround the outer periphery of the cylinder block (2), and a reference numeral 4 denotes an end cap. Reference numerals 5, 5, . . . (See FIG. 2) denote a plurality of cylinders disposed in the cylinder block (2), a reference numeral 6 denotes a piston housed in each of the cylinders (5), and a reference numeral 7 denotes a distribution valve for distributing working oil to the cylinders (5, 5, . . . ). Reference numerals 8a, 8b, 8c, 8d denote annular communication passages as four communication passages formed so as to surround the outer periphery of the distribution valve (7), a reference numeral 9 denotes a supply/discharge operating valve as a selector valve for selectively connecting the annular communication passages (8a, 8b, 8c, 8d) to an oil supply side or an oil discharge side for working oil, and a reference numeral 10 denotes an output shaft. The cam motor apparatus A is provided in a construction machine or the like for driving wheels, crawlers or the like.
The casing body (1) is disposed coaxially with the output shaft (10) and is connected to an approximately conical casing cover (11) disposed at a part of the output shaft (10) located at one side along the length of the output shaft (10) (a left side of FIG. 1: hereinafter, referred to as a left side), through a plurality of bolts (11a, 11a, . . . ). Further, the casing body (1) is connected at the other side of the output shaft (10) (a right side of FIG. 1: hereinafter, referred to as a right side) to the cam ring (3) and the end cap (4) through a plurality of bolts (12, 12, . . . ) (See FIG. 2). In this manner, a casing (13) forming a main body of the cam motor apparatus A is formed. The output shaft (10) passes through the casing (13) in a lateral direction of FIG. 1 and is rotatably supported to the casing (13) through tapered roller bearings (111, 41) respectively disposed in the casing cover (11) and the end cap (4). In the outer peripheries of the casing body (1) and the end cap (4), mounting flanges (14, 14, . . . ) protruding outward are provided. The casing (13) is fixed to a vehicle body through the mounting flanges (14, 14, . . . ).
The cylinder block (2) is coupled to the outer periphery of the output shaft (10), for example, by spline coupling, and is disposed so as to rotate on a rotational axis (X) (i.e., a central axis of the cylinder block (2) together with the output shaft (10). In the cylinder block (2), as shown in FIG. 2, a plurality (eight in the figure) of cylinders (5, 5, . . . ) are radially formed around the rotational axis (X) at uniform intervals in a circumferential direction, extend outward in a radial direction of the cylinder block (2) and are open in the outer periphery of the cylinder block (2). Each of the cylinders (5) houses a piston (6). Each of the pistons (6) rotates a roller (61) formed at an end thereof, along a cam surface (3a) formed in the inner periphery of the cam ring (3) , and concurrently extends and retracts in the cylinder (5) in a manner to be guided by the cam surface (3a). Further, in the cylinder block (2), eight distributed-side ports (21, 21, . . . ) are formed so as to be communicated with the respective cylinders (5, 5, . . . ) and to be open in the end surface (2a) (i.e., a right-end surface in the figure) of the cylinder block (2) at uniform intervals on a circumference around the rotational axis (X).
As shown in FIG. 2, the cam ring (3) is provided at the cam surface (3a) with a specified count (six in the figure) of convex parts (31, 31, . . . ) and a specified count (six in the figure) of concave parts (32, 32, . . . ), which are alternately formed at uniform intervals in a circumferential direction and whose counts are determined based on the piston count and arrangement. As for the positional relationships of the eight pistons (6, 6, . . . ) to the cam surface (3a), when the piston (6) located at the upper right of FIG. 2 is termed a first piston and other pistons are sequentially termed second to eighth pistons in a clockwise direction, these pistons are positioned such that the first and fifth pistons (6, 6) each come into contact with approximately the bottom point of the concave part (32), the second and sixth pistons (6, 6) each come into contact with approximately a middle point between the concave part (32) and the convex part (31) (i.e., each enter the descending cycle) , the third and seventh pistons (6, 6) each come into contact with approximately the top point of the convex part (31) and the fourth and eighth pistons (6, 6) each come into contact with approximately a middle point between the convex part (31) and the concave part (32) (i.e., each enter the ascending cycle).
Under the above positional relationships, when working oil is mainly supplied to the fourth and eight pistons (6, 6) such that they press the cam surface (3a), the cylinder block (2) rotates in a counterclockwise direction of FIG. 2 (a direction shown in arrows) around the central axis (X). Subsequently, when working oil is mainly supplied to the third and seventh pistons (6, 6), the cylinder block (2) further rotates. This rotation causes the second and sixth pistons (6, 6) to overcome the convex part (31) and working oil is then supplied to the second and sixth pistons (6, 6). In this manner, working oil is distributively supplied to the pistons (6, 6, . . . ) so that the cylinder block (2) and the output shaft (10) are successively driven into rotation in one piece.
The distribution valve (7) is formed in approximately a column, is disposed such that one end surface (7a) thereof (a left-end surface: hereinafter, referred to as a coupled end surface) is relatively rotatably coupled to the right-end surface (2a) of the cylinder block (2), and is fixed in a non-rotating state in a manner to be fitted in the end cap (4). In the inner periphery of the end cap (4), four annular concave parts, arranged in a longitudinal direction of the output shaft (10) (a lateral direction of FIG. 1), are formed over the circumference and are open so as to correspond to the shape of the outer periphery of the distribution valve (7). The annular concave parts and the outer periphery of the distribution valve (7) define second, fourth, first and third annular communication passages (8a, 8b, 8c, 8d) in the order from the left end. In the coupled end surface (7a), as shown in FIG. 3, distribution ports (71, . . . , 72, . . . , 73, . . . , 74, . . . ), whose count is an integral multiple (12 in the figure) of the count of the convex parts (31, . . . ) or the count of the concave parts (32, . . . ) of the cam surface (3a), are provided so as to be communicable with the distributed-side ports (21, 21, . . . ) disposed in the right-end surface (2a) of the cylinder block (2) and so as to be open at uniform intervals on the same circumference where the distributed-side ports (21, 21, . . . ) are located.
The distribution ports (71, . . . , 72, . . . , 73, . . . , 74, . . . ) are divided into a first distribution port group composed of first distribution ports (71, 71, . . . ) arranged every three ports in a circumferential direction, a second distribution port group composed of second distribution ports (72, 72, . . . ) each disposed next to the first distribution port in a direction of normal rotation of the cylinder block (2) (in a counterclockwise direction of FIG. 3), a third distribution port group composed of third distribution ports (73, 73, . . . ) each disposed next to the second distribution port in the same direction, and a fourth distribution port group composed of fourth distribution ports (74, 74, . . . ) each disposed next to the third distribution port in the same direction. An end (a right end in FIG. 3) of each of the first distribution ports (71) located far from the cylinder block (2) extends to the first annular communication passage (8c) in the longitudinal direction of the output shaft (10) so as to be communicated with the first annular communication passage (8c). Similarly, the second distribution ports (72, 72, . . . ) are individually communicated with the second annular communication passage (8a), the third distribution ports (73, 73, . . . ) are individually communicated with the third annular communication passage (8d), and the fourth distribution ports (74, 74, . . . ) are individually communicated with the fourth annular communication passage (8b).
Among the four annular communication passages (8c, 8b, . . . ), the first annular communication passage (8c) is connected to a main pump (15) through a supply passage (81), and receives working oil discharged from the main pump (15) when the cam motor apparatus (A) is normally rotated. On the other hand, the second annular communication passage (8a) is connected to the main pump (15) through a discharge passage (82), and returns working oil, discharged from the cylinder block (2), to the main pump (15) when the cam motor apparatus (A) is normally operated. A working oil supply system (150) is formed of: a closed circuit composed of the main pump (15), the supply passage (81), the discharge passage (82) and so on; and a charging pump (16) for adding charging oil to the passage that is put under low pressure so as to cope with leakage of working oil from the closed circuit. The main pump (15) is configured so as to be reversible between a suction direction and a delivery direction of working oil. Under this configuration, when the oil supply side and the oil discharge side of the working oil supply system (150) are reversed each other so that working oil is supplied to the discharge passage (82), the output shaft (10) is reversely rotated. As a result, the cam motor apparatus (A) can be reversely rotated.
The supply/discharge operating valve (9) is composed of a valve room (91) formed in the end cap (4) so as to have a circular form in cross section and a cylindrical valve element (92) housed in the valve room (91) so as to be slidable in a longitudinal direction (a lateral direction). As shown in FIGS. 4 and 5 in detail, the valve room (91) includes first, second, third and fourth enlarged-diameter parts (91a, 91b, 91c, 91d) in the order from the left side of the figures (hereinafter, referred to as the left side). These four enlarged- diameter parts (91a, 91b, 91c, 91d) are individually communicated with the four annular communicationpassages (8a, 8b, 8c, 8d) through four communication passages (83a, 83b, 83c, 83d) formed in the end cap (84).
At the right end of the valve room (91) in FIGS. 4 and 5 (hereinafter, referred to as the right end), a cylinder part (91e) is formed. When a selector valve (161) (See FIG. 1) is in its right position, the cylinder part (91e) receives pressurized oil from the charging pump (16) through a charging oil supply passage (93) to operate the valve element (92). The valve element (92) comprises first, second and third large-diameter parts (921, 922, 923) in the order from the left side, small-diameter parts (924, 925) intermediately formed among the large- diameter parts (921, 922, 923), and a charge pressure supply passage (926) which is open at one end thereof on the right end surface of the valve element (92) and passes through the valve element (92) along the length of the valve element (92) (in a lateral direction of the figure) such that the other end extends to the second large-diameter part (922). The charge pressure supply passage (926) has four openings (926a, 926a, . . . ) formed in the outer periphery of the second large- diameter part (922) at uniform intervals in a circumferential direction and four openings (926a, 926a, . . . ) formed in the outer periphery of the third large- diameter part (923) at uniform intervals in a circumferential direction.
As shown in FIG. 4, the valve element (92) is urged rightward by resilient forces of springs (94, 95) so as to be positioned in a low rotational speed position. In this low rotational speed position, the valve element (92) communicates the third enlarged-diameter part (91c) with the fourth enlarged-diameter part (91d) and concurrently communicates the first enlarged-diameter part (91a) with the second enlarged-diameter part (91b). Accordingly, when the valve element (92) is in the low rotational speed position, the first and third annular communication passages (8c, 8d) are communicated with the supply passage (81) and concurrently the second and fourth annular communication passages (8a, 8b) are communicated with the discharge passage (82).
On the other hand, when the cylinder part (91e) is supplied with charge pressure, the charge pressure causes the valve element (92) to move leftward against the resilient forces of the springs (94, 95) so that the valve element (9) is changed into a high rotational speed position as shown in FIG. 5. As a result, the second enlarged-diameter part (91b) is communicated with the fourth enlarged-diameter part (91d) through the charge pressure supply passage (926). At the time, the charge pressure is transmitted from the cylinder part (91e) to the second and fourth enlarged-diameter parts (91b, 91d) through the charge pressure supply passage (926), whereas the first and third enlarged- diameter parts (91a, 91c) are each put into a state that communication with other enlarged-diameter parts is interrupted. In other words, the first annular communication passage (8c) is communicated with the supply passage (81), the second annular communication passage (8a) is communicated with the discharge passage (82), and the third and fourth annular communication passages (8d, 8b) are communicated with each other and are supplied with charge pressure.
Accordingly, when the valve element (92) of the supply/discharge operating valve (9) is in the low rotational speed position (See FIG. 4), working oil having passed through the supply passage (81) is supplied to each of the first and third distribution ports (71, 73), whose total number is 6, through the third and fourth enlarged-diameter parts (91c, 91d) and the first and third annular communication passages (8c, 8d), so that the distribution ports (71, 73) are put under high pressure. Concurrently, the second and fourth distribution ports (72, 74), whose total number is 6, are communicated with the discharge passage (82) through the second and fourth annular communication passages (8a, 8b) and the first and second enlarged- diameter parts (91a, 91b) and thereby are put under low pressure. In short, six among the twelve distribution ports (71, . . . , 72, . . . , 73, . . . , 74, . . . ) are under high pressure and the remaining six are under low pressure.
On the other hand, when the valve element (92) of the supply/discharge operating valve (9) is in the high rotational speed position (See FIG. 5), working oil having passed through the supply passage (81) is supplied to the three first distribution ports (71) through the third enlarged- diameter part (91c) and the first annular communication passage (8c) so that the first distribution ports (71) are put under high pressure. Concurrently, the three second distribution ports (72) are communicated with the discharge passage (82) through the second annular communication passage (8a) and the first enlarged- diameter part (91a) and thereby are put under low pressure, and the three third distribution ports (73) are communicated with the three fourth distribution ports (74) through the third and fourth annular communication passages (8d, 8b) and the second and fourth enlarged- diameter parts (91b, 91d) and are held under charge pressure. In short, three among the twelve distribution ports (71, . . . , 72, . . . , 73, . . . , 74, . . . ) are under high pressure, another three distribution ports are under low pressure and the remaining six distribution ports are supplied with charge pressure.
In FIG. 1, a reference numeral 17 denotes a negative brake mechanism for blocking rotation of the output shaft (10). The negative brake mechanism (17) has a plurality of pressure rings affixed on the outer periphery of the output shaft (10) and pressure plates each interposed between the adjacent pressure rings and affixed on the inner periphery of the casing body (1). When supplied with no pressurized oil from the charging pump (16), the negative brake mechanism (17) makes the pressure rings and the pressure plates pressed against each other by a pressing force urged by a belleville spring (18) to cause a frictional force due to slide therebetween, and the frictional force blocks rotation of the output shaft (10) relative to the casing body (1). On the other hand, when the negative brake mechanism (17) is supplied with pressurized oil from the charging pump (16), the pressure rings are separated from the pressure plates so that the output shaft (10) is released from the brakes to become freely rotatable.
Description will be made below about operations and effects of the cam motor apparatus A of this embodiment.
First, the charging pump (16) is activated so that the negative brake mechanism (17) is supplied with pressurized oil. Thereby, the output shaft (10) is released from the brakes applied by the negative brake mechanism (17). Subsequently, the main pump (15) is activated so that the supply passage (81) is supplied with working oil.
At this point, in the case where the cam motor apparatus A is rotated in a low-speed mode, the selector valve (161) is changed into its left position to block the supply of pressurized oil from the charging pump (16) to the supply/discharge operating valve (9). As a result, the valve element (92) of the supply/discharge operating valve (9) is positioned in the low rotational speed position (See FIG. 4) so that the first and third distribution ports (71, 73), whose total number is 6, are changed into ports for supplying working oil while the second and fourth distribution ports (72, 74), whose total number is 6, are changed into ports for discharging working oil. Thereby, working oil is supplied to a half of the eight cylinders (5, 5, . . . ), i.e., four cylinders (5, 5, . . . ) in the ascending cycle (i.e., the third, fourth, seventh and eighth cylinders of FIG. 2), so that the pistons (6, 6, . . . ) housed in these cylinders (5, 5, . . . ) each generate a driving force, which causes the cylinder block (2) and the output shaft (10) to rotate together. This rotation provides a change in positional relationship between the cylinder block (2) and the distribution valve (7). As a result, working oil is supplied to another four cylinders (5, 5, . . . ) that subsequently enter the ascending cycle (i.e., the second, third, sixth and seventh cylinders in FIG. 2) so that the cylinder block (2) further rotates. Such an operation is repeated so that the cylinder block (2) and the output shaft (10) successively rotate. On the other hand, working oil is discharged from four cylinders (5, 5, . . . ) in the descending cycle by their pistons (6, 6, . . . ) and is returned to the suction side of the main pump (15) through the discharge passage (82). In this manner, the cam motor apparatus A in the low-speed mode is rotated with a maximum motor capacity at relatively low speed and relatively high output torque.
In the case where the cam motor apparatus A is rotated in a high- speed mode, the selector valve (161) is changed into its right position to allow the supply of pressurized oil from the charging pump (16) to the supply/discharge operating valve (9). As a result, the valve element (92) of the supply/discharge operating valve (9) is positioned in the high rotational speed position (See FIG. 5), so that the three first distribution ports (71) are changed into ports for supplying working oil, the three second distribution ports (72) are changed into ports for discharging working oil, and the third and fourth distribution ports (73, 74), whose total number is 6, are communicated with each other and are supplied with charge pressure. Thereby, working oil is supplied to a quarter of the eight cylinders (5, 5, . . . ), i.e., a half of four cylinders (5, 5, . . . ) in the ascending cycle (the fourth and seventh cylinders in FIG. 2), so that the pistons (6, 6) housed in the two cylinders (5, 5) each generate a driving force. On the other hand, working oil is discharged from a half of four cylinders (5, 5, . . . ) in the descending cycle (i.e., the first and sixth cylinders in FIG. 2). Further, in each of the remaining four cylinders (5, 5, . . . ) (i.e., the second, third, fifth and eighth cylinders in FIG. 2), the piston (6) reciprocates in the cylinder (5) along the cam surface (3a) but generates no driving force. In this manner, the cam motor apparatus A in the high- speed mode is rotated with approximately half the motor capacity in the low-speed mode at relatively high speed and relatively low output torque.
In the high-speed mode, charge pressure is supplied to the cylinders (5) connected to neither the ports for supplying working oil nor the ports for discharging working oil, so that the pistons (6) are held in slide contact with the cam surface (3a). This prevents collision between the pistons (6) and the cam surface (3a), thereby providing increase in silentness and durability. Further, since there is no need for providing a spring for pressing the pistons (6) against the cam surface (3a), the component count of the cam motor apparatus A can be decreased as compared with the conventional case. This reduces the weight of the entire apparatus and increases ease of assembly.
Furthermore, in the cam motor apparatus A of this embodiment, the third distribution ports (73, 73, . . . ) and the fourth distribution ports (74, 74, . . . ) are connected in the high-speed mode, and the charge pressure supply passage (926) for supplying charge pressure to the third and fourth distribution ports (73, . . . , 74, . . . ) is formed in the valve element (92) of the selector valve (9). This compacts the oil pressure circuit for supplying charge pressure, which compacts the entire apparatus.
In the case where the cam motor apparatus A is reversely rotated, the main pump (15) is reversely operated between its suction direction and its delivery direction so that the oil supply side and the oil discharge side of the working oil supply system (150) are reversed each other, which allows working oil to be supplied to the discharge passage (82). When the cam motor apparatus A is reversely rotated in the low- speed mode, the supply/discharge operating valve (9) is positioned into the low rotational speed position as in the case of the normal rotation in the low-speed mode, so that the second and fourth distribution ports (72, 74), whose total number is 6, are changed into ports for supplying working oil while the first and third distribution ports (71, 73), whose total number is 6, are changed into ports for discharging working oil. Thereby, working oil is supplied to the four cylinders (5, 5, . . . ) in the ascending cycle while working oil is discharged from the four cylinders (5) in the descending cycle. As a result, the cam motor apparatus A can be rotated at relatively low speed and relatively high output torque.
On the other hand, when the cam motor apparatus A is reversely rotated in the high-speed mode, the supply/discharge operating valve (9) is changed into the high rotational speed position as in the case of the normal rotation in the high-speed mode, so that the three second distribution ports (72) are changed into ports for supplying working oil, the three first distribution ports (71) are changed into ports for discharging working oil, and the third and fourth distribution ports (73, 74), whose total number is 6, are communicated with each other and are supplied with charge pressure. Thereby, working oil is supplied to a half of the four cylinders (5, 5, . . . ) in the ascending cycle while working oil is discharged from a half of the four cylinders (5, 5, . . . ) in the descending cycle. As a result, the cam motor apparatus A can be rotated at relatively high speed and relatively low output torque.
Comparison will be made below between the cam motor apparatus in reverse rotation of this embodiment and the conventional cam motor apparatus illustrated in FIG. 6. The conventional cam motor apparatus is configured such that a plurality of pistons and cylinders are divided into three piston-cylinder groups and working oil is distributed among the three piston-cylinder groups through three communication passages (108a, 108b, 108c), respectively. Specifically, twelve distribution ports are divided into a group of six first distribution ports (not shown), a group of three second distribution ports (not shown) and a group of three third distribution ports (110) (only one port is shown in the figure). The first communication passage (108a) located on the left side of the figure (hereinafter, referred to as the left side) is communicated with the first distribution ports, the second communication passage (108b) located in the middle position is communicated with the second distribution ports, and the third communication passage (108c) located on the right side of the figure (hereinafter, referred to as the right side) is communicated with the third distribution ports. Further, the first communication passage (108a) is communicated with a discharge passage for working oil and the third communication passage (108c) is communicated with a supply passage for working oil.
When the conventional cam motor apparatus is normally rotated in the high-speed mode, the three third distribution ports (110) are supplied with working oil through the third communication passage (108c) so as to be put under high pressure, whereas the six first distribution ports and the three second distribution ports are put under low pressure through the first communication passage (108a) and the second communication passage (108b), which are communicated with each other by a selection of a supply/discharge operating valve (109).
When the conventional cam motor apparatus is reversely rotated in the high-speed mode, in contrast to the case of the above-described normal rotation, the first communication passage (108a) and the second communication passage (108b) are supplied with high-pressure working oil through the discharge passage, so that the six first distribution ports and the three second distribution ports are put under high pressure, whereas the third communication passage (108c) is communicated with the supply passage so that the three third distribution ports (110) are put under low pressure. In this manner, in the conventional cam motor apparatus, high-pressure working oil is supplied not only to the cylinders generating driving forces for reverse rotation but also to the cylinders generating no driving force. This extremely increases rotational resistance and increases ill thermal effect.
On the other hand, when the cam motor apparatus A of this embodiment is reversely rotated in the high-speed mode, high-pressure working oil is supplied to the second annular communication passage (8a) (See FIG. 5) through the discharge passage (82), and the first annular communication passage (8c) is communicated with the supply passage (81) so that working oil is discharged. Further, as is the case with the normal rotation in the high-speed mode, the third and fourth annular communication passages (8d, 8b) are supplied with charge pressure having the same pressure as in the discharge side of the working oil supply system (150) and the charge pressure can hold slide contact between the piston (6) and the cam surface (3a) without producing large rotational resistance. This largely decreases rotational resistance with the operation of the piston (6) as compared with the conventional case as shown in FIG. 6, minimizes ill thermal effect and provides increase in silentness and durability also during reverse rotation in the high-speed mode.
The present invention is not limited to the above embodiment and can include various kinds of other embodiments. For example, though the cam motor apparatus A of the above embodiment has a configuration that the cam ring (3) is affixed to the casing (13) and the output shaft (10) is connected to the cylinder block (2) rotating relative to the cam ring (3), the cam motor apparatus of the present invention can have a configuration that the cylinder block is affixed to the main body of the apparatus and an annular casing with a cam ring is rotated relative to the cylinder block.
Further, though the cam motor apparatus of the above embodiment has a configuration that six convex parts (31, 31, . . . ) and six concave parts (32, 32, . . . ) are formed in the cam surface (3a) of the cam ring (3) and eight pistons (6, 6, . . . ) are correspondingly disposed in the cylinder block (2), another embodiment of the present invention can have a configuration that both a convex part count and a concave part count are same values other than 6 and pistons whose count is a value except 8 are correspondingly disposed.
INDUSTRIAL APPLICABILITY
According to the present invention, in a cam motor apparatus selectable between two stages of high and low rotational speeds, noise reduction and increased durability can be achieved in the high rotational speed mode, and the component count of the apparatus can be reduced, resulting in weight reduction and cost reduction. This contributes to widespread use of the cam motor apparatus. Accordingly, the present invention has a high industrial applicability. | |
..and 18, dang it.
Last week my dad posted on his blog about (one of) his (many) twenty mile run(s). I'm Jake Emmett and "make mine a 20!" he said.. Well I'm just his daughter, so make mine an 18.
But, hey! An 18! Today I ran eighteen miles, in three loops of six miles. And I passed two different Taco Bells three different times each. Eighteen miles, six Taco Bells, breaking all my PR's in one morning..
After twelve miles I really didn't want to go do another loop. But then I remembered how the day before, Stefan had asked me if I consider myself to be a self-driven person. I thought about all my marathon training and my time at Disneyworld and deciding to go to college and everything I accomplished in high school and I decided, yeah. I think I am a pretty self-driven person. And self-driven people don't quit at twelve miles, dang it! dang it.. sooo, eighteen it was.
After my run I went to the Provo temple to do baptisms for the dead. After the temple I went to see Lindsay, Taylor, Meg, and Jess. While I was with them I stuffed myself with Costa Vida and a milkshake and that, dear internet, is my kind of day.
3 comments :
- Lesa Emmett said...[Reply to comment]
-
Way.To.Go!
- August 30, 2013 at 10:36 PM
- Molly Seawright said...[Reply to comment]
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Freak yeah, internet! That's my baby sissy!
- September 1, 2013 at 11:45 AM
- Jake Emmett said...[Reply to comment]
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Congratulations on the milage AND Taco Bell PRs! Those TB PRs are so rare but oh so special. Unfortunately, I don't believe the TOU marathon passes any Tacos el Bellos but it does go pass one Chuck-A-Ramma! | http://www.girlerin.com/2013/08/make-mine-an-18-dang-it.html |
Definition of year to date (accounting): The cumulative financial result from the start of the latest accounting year until the present day.
What is Year to Date (YTD)?
Year to date is the name for a period of time without a fixed meaning. Its context depends on when the present day falls within the financial year.
Year to date is often abbreviated to YTD for the sake of brevity, particularly when used in financial charts and tables to quickly set the context for a figure. For example:
Turnover:
This month: £450,900
YTD: £2,463,400
About financial years
A financial year, or accounting period, is the calendar over which a company measures and reports its results.
It is common for a company to use the ordinary calendar year beginning January as their financial year. This means that their year end is the 31 December.
However, companies have the free choice to start their financial year at any point. Many UK businesses choose to have a year-end of 31 March or 30 April. 30 September is also not uncommon.
Having an obscure financial year-end can help lower accounting and professional service fees, because it may move the timing of the preparation of accounts and tax returns to outside of the busiest period for accounting professionals.
Year to date or YTD may refer to the calendar year, or it may refer to the financial year. This should not be assumed when a company has a financial year-end which differs from the calendar year.
How is the phrase year to date used in a sentence?
“The YTD turnover as per the general ledger is £35,000.”
“While profits are down in the month, year to date profits are still ahead of budget.”
How does the definition of year to date (YTD) relate to investing?
As an investor in company stocks & shares, you may hear references to ‘year to date’ when reviewing interim financial statements or trading updates provided by management teams.
As you read management accounting books, you’ll notice that all management information is expressed as a current month, or a year-to-date measure. I.e. live versus cumulative performance. | https://www.financial-expert.co.uk/year-to-date-ytd-definition/ |
At the dawn of the modern era, Galileo discovered and described how composite bodies fall through the air (or at least the discovery is usually attributed to him).
I'm interested in whether this had been discovered earlier and how, particularly since it seems to me that there are good grounds for this result to hold true purely on the basis of continuity and symmetry.
Imagine three balls of the same size and weight, and at equal distances from each other, dropped from a tower at the same time. By symmetry, all three must hit the ground at the same time.
Now repeat the experiment, but move the left-hand ball next to the middle one. This makes no difference to the result—the three balls still hit the ground at the same time.
Now repeat the experiment once more after slightly increasing the contact area of the two adjacent balls. Again, I would expect them to hit the ground at the same time. By repeating this, the left-hand and middle balls eventually merge into a single larger ball, which will fall at the same time as the right-hand one.
Did anyone make this argument in the pre-modern literature? I'd be interested to know whether any of the ancient atomists came up with similar arguments when they considered how atoms moved under gravity. It ought to have then been a simple step via the above argument to see that composite bodies fall at the same rate. | https://physics.stackexchange.com/questions/28097/were-there-any-efforts-made-by-early-physicists-to-discover-and-explain-how-comp |
Don't Feed the Artists is a show about music featuring interviews, topical discussions, stories about important moments in music, deep dives into artist's discographies, and more. New episodes Wednesdays.
From Austin, this week's guest is Strange Mother y'all! We talk about venn diagrams, how they named their band, wrestling, the music scene in Austin, and more!
Strange Mother - Blueberry for NPR's Tiny Desk
See Strange Mother in Austin at Cheer Up Charlies on August 3rd
Harry Styles - Harry Styles
Parcels & Daft Punk - Overnight
Kendrick Lamar - Damn
The Chronic 2001
Wipers
Parquet Courts - Light Up Gold
Darkthrone
Number Girl
What're You Listening To? Email us and let us know! | https://dfta.show/?name=2017-08-01_e0015_strange-mother.mp3 |
Q:
How to prevent grid-row span from changing column placement?
I have a 3 X 3 CSS Grid.
I have a row in which I have three items A, B & C.
I want item C to have a rowspan of 2.
To do so, I am using grid-row: 1 / span 2;. It is taking two rows, but it's being placed in the first column instead of simply lying in the 3rd column. I don't know why this is happening.
I want item C to stay at the place where it is in the HTML.
One work around to this problem is to explicitly setting grid-column: 3 / span 1 which I don't want to do. I want items to be placed the way they are in HTML.
Is there any way to suppress this behavior?
.grid-container {
display: grid;
grid-template-columns: repeat(3, 1fr);
grid-template-rows: repeat(3, 1fr);
}
h1 {
border: 2px solid;
padding: 0;
margin: 0;
font-size: 20px;
}
.a {
grid-row: 1 / span 2;
background: orange;
}
<div class="grid-container">
<div>
<h1>A</h1>
</div>
<div>
<h1>B</h1>
</div>
<div class="a">
<h1>C</h1>
</div>
</div>
A:
Another way of solving it (That points to the reason why is stating a row for the other items):
}
}
}
.b {
grid-row: 1;
}
<div class="grid-container">
<div class="b">
<h1>A</h1>
</div>
<div class="b">
And the reason of this behaviour is that the more restrictive elements get positioned first. This way, the possibilities of the grid algorithm to achieve a solution are bigger.
That is, an element that has a requirement will be positioned first, elements that don't have a requirement last.
Steps 2 (for a item) and 4 (for the remaining items) in this part of the spec
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The present application relates to a new and improved construction of a step of an escalator or moving stairway or the like, particularly a step equipped with at least one warning device for warning the passenger that he or she has tread on a danger zone of the step.
Generally speaking, the step of the escalator comprises a step body equipped with a tread surface and a front or riser surface. The step further contains two side uprights or plates, each provided with a drag roller or roll and each provided with a fixing device for connection to an endless transport means. A step band or run composed of a number of steps and two endless transport means is guided between two fixed skirt guards.
In escalators or moving stairways there exists, between the moving step and the fixedly arranged skirt guards, a latent risk of entrapment or catching of the passenger's shoe, especially when wearing light or flimsy footwear. Even in escalators of the most different types of construction shoe pinching or catching accidents occur from time to time. During these accidents, fortunately, usually only gymnastic shoes, tennis shoes, rubber or plastic boots are pulled-in between the side uprights or plates of the step and the fixed skirt guards, whereas the foot can mostly still leave the caught footwear. Such accidents usually occur when the passenger places his or her foot laterally so near to the edge of the tread surface of the step that the shoe brushes or wipes against the related fixed skirt guard positioned laterally besides the step.
Apart from the thus ensuing friction opposite to the direction of travel which prevails between the passenger's shoe and the related skirt guard, there also occurs at the escalator transition locations a relative movement with a friction transverse to the direction of escalator travel. Depending on the direction of travel of the escalator, this transverse friction occurs at the upper or lower transition locations where the risers of the steps disappear, i.e. retract, or form, i.e. deploy as the case may be. Through the action of this transverse friction light footwear especially can be pulled-in between the moving step and the fixed skirt guard.
Various inventions have become known to the art by means of which attempts were and are being made to overcome the above-described danger:
Minimizing the distance between the step and the skirt guard by means of special guide devices positioned at the step and centering the step by means of the skirt guard.
Marking of the side and rear parts of the step as danger zones by coloring or inserting different colored edge or margin strips.
Reducing the coefficient of friction by covering the skirt guard with a slide or non-friction layer, e.g. formed of "TEFLON".
Raising the side parts of the tread surface of the step, also by means of inserts, so that these will be avoided because of the uncomfortable foot position.
Fan-type swivelling or pivoting safety or protective walls positioned laterally beside the step and by means of which the relative movement between the step and the skirt guard is screened.
Positioning of safety contacts along the skirt guard, especially at a predetermined distance before the entry of the step into the comb.
A step for escalators with a safety device of this type has become known from the European Pat. No. 0,087,692, published Sept. 7, 1983. Laterally at the steps there are provided two-piece, swivelling apart, fan-type side walls that ar arranged about a common pivot over the drag or trailing roller at the side plate. In the horizontal entrance or exit zone the two side wall parts lie against the step body and conjointly rest next to each other on the axle connecting the step with the transport means. At the transition from the horizontal to the slanting or sloped runway or travel path, at the location where the step risers form or deploy, there first rises or ascends the one side wall part entrained by the neighboring leading step. This, in turn, entrains the second side wall part in a fan-type manner so as to fully cover the triangle towards the skirt guard. This triangle is formed between the tread plate of the one step and the front part of the preceding step in the region of the sloped runway or travel path. The relative movement occurring up to now between the moving step and the fixed skirt guard is thus transformed into a relative movement between the moving step and the side wall moving with the same speed. Thus, while the danger of lateral pinching or entrapment of the shoe is markedly reduced, it is however not rendered totally impossible.
A further construction of step for escalators and equipped with a safety device as mentioned above is disclosed in the German Pat. No. 2,161,442, published July 13, 1972. Here the lateral edge strips and the edge strips of the tread plate directed towards the front part of the neighboring step, are made of colored, differently formed inserts. The lateral insert pieces can additionally rise above or protrude beyond the tread height of the rest of the tread plate. The function of the colored edge strips is to optically indicate to the passenger those parts of the tread plate which should not be stepped upon. Additionally, the possibly raised lateral insert pieces should, when being trod upon by the passenger, result in an uncomfortable foot position and should require him or her to remove his or her foot from this area.
A disadvantage of this prior art construction exists in that when heavy passenger frequency occurs, the colored edge parts will not be noticed or will be completely non-visible and that the lateral raised edge parts of the tread plate, because of structural reasons (greater spatial requirements in the area of the upper and lower turning points covered by the entrance plates) will not be designed with such a height that the passenger will find that standing on them will actually cause an uncomfortable foot position.
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Half-marathon held by following all the safety protocols
Half-marathon held by following all the safety protocols
Sebastian Coe, the head of the World Athletics, said a half-marathon test event run here on Wednesday made him confident that the Olympic marathon can be held successfully in the city when the Tokyo Games opens in just under three months.
Spectators were encouraged to stay off the streets and not watch the race in person. Security officials held signs on the roads that read: ”Please refrain from watching the event from here.”
The smattering of competitors from abroad were largely restricted to their hotel rooms while not competing or training. Coe said strict protocols measures against COVID-19 were followed.
Coe said “today Sapporo demonstrated the highest level of capability to organise successful” marathon and race walk events. Those events are being held outside of Tokyo because of the city’s hot summers.
Coe will be on hand on Sunday when Tokyo organisers hold another test event at the new $1.4 billion National Stadium in Tokyo.
Organisers have held a series of test events in the last several days and have reported few problems. The largest problem is convincing the Japanese population that the Olympics, with 11,000 athletes and thousands of others, should take place in the middle of a pandemic.
“You can understand the concern,” Coe told a news conference. He tried to reassure by saying that one-fifth of the athletes in the Olympics represent track and field — and that World Athletics can meet the challenge.
“Everybody, the athletes particularly, will hope for spectators,” Coe said. “But I think they recognise that if that’s not possible then the Games will still take place and the competition will still be extremely good.”
He said athletes had become used to competing at stadiums where there aren’t any crowds.
“The challenges are big. I don’t believe any Olympic Games has been delivered under more difficult circumstances,” Coe said.
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Knitting for newborns
Maxine Colyer has been knitting since World War I.
About 20 years ago, the Hollidaysburg woman who turns 102 on Tuesday, started making baby hats to donate to then Altoona Hospital.
She’s still at it today.
“I hurt my right hand a couple of months ago and couldn’t knit for about a month, but I am back knitting now. I am getting back into my groove,” Colyer said. “I just do it to keep busy. I just like to knit, so I keep on doing it.”
Since 1994, Colyer has spent more than 6,300 hours making the hats and has donated more than 1,250 to the hospital, said Debbie McClellan, UPMC Altoona manager of volunteer services.
Colyer is one of the many volunteers who donate the baby hats to the hospital’s maternity department. More than 900 have been donated so far this year.
“Our knitting volunteers create a very nice selection of beautiful pastel colored hats, but they go above and beyond with imaginative and colorful designs for special occasions, holidays, notable dates and seasonal themes,” McClellan said.
Parents of newborns appreciate the effort.
“Parents appreciate the time and effort that is required in making the newborn hats. The hats do serve a purpose as an infant may lose body heat, and the hat helps keep his or her temperature stable. Parents also like to choose a certain color or design as we may have several choices depending on which volunteers are making them,” said Pam O’Donnell, nurse manager of the maternity and nursery department.
“The parents are very appreciative. A lot of times if they don’t like the color, they can trade and get a color they like. We just put a hat in each crib. They can choose and get what they want,” said Kathy Bost, a registered nurse in the maternity and nursery department.
Kathy Loose of Altoona has been making and donating the baby hats for about five years.
“It is a way to do something for the community, and it is fun. I do the seasonal hats; the people just love them,” Loose said.
“For Valentines Day, I make a white hat with a red heart,” Loose said. “For Easter, I have a plain one with bunny ears on it. I make a Frankenstein hat for the boys at Halloween, pumpkin hats for fall and Thanksgiving, and I also make Christmas hats. There are all kinds you can do.”
Emily Jo Donlan, daughter of Robert and Brigitte Donlan, received two hats made by Loose – one with flowers and another a witch hat – after she was born Oct. 2 at UPMC Altoona.
“I think this is a nice gesture. It was cool. I never expected a Halloween hat. It was a nice surprise,” Brigitte Donlan said.
A group called the Presbyterian Village Knitters and Crocheters of Hollidaysburg started donating baby hats this summer. | http://www.altoonamirror.com/news/local-news/2013/11/knitting-for-newborns/ |
Malaysia’s Second Space Mission On, But Not Soon
KUALA LUMPUR, Nov 24 – Malaysia plans to have its second astronaut stay in the International Space Station for weeks or months instead of days, but the second space mission is unlikely to take place soon – at least not in the next couple of years.
National Space Agency Director-General Dr Mustafa Subari said time was necessary to work out the details of the preparations and for the negotiation process with potential collaborators.
A few things had to be sorted out before the mission could be launched, including partnership and the types of experiment to be conducted on board the ISS, he told Bernama.
He gave the assurance, however, that the programme had received the nod from the government, considering the benefits it would bring to the nation.
“It is ongoing but it won’t happen in the next few years, maybe at the end of the 10th Malaysia Plan (10MP). But the commitment given by the government under the 10MP is a good start,” he said.
Mustafa said the agency was still in the midst of negotiating with potential collaborators such as the Russian Federal Space Agency (Roscosmos) and the National Aeronautics and Space Administration (Nasa) in order to provide the necessary facilities and arrangements.
“To date, the negotiations are still not finalised. We haven’t got any concrete proposals from them as yet,” he said.
He said that unlike the first mission, Malaysia planned to send the second astronaut on a longer mission to the ISS. Malaysia’s first astronaut Datuk Dr Sheikh Muszaphar Shukor spent only 10 days in the ISS in October 2007 and conducted five experiments.
“It (the last mission) was quite short. So, for the second mission, we hope to have the astronaut stay longer in the ISS, maybe a few weeks to months, so that he can carry out more scientific experiments on micro gravity,” he said.
Recently, Science, Technology and Innovation Minister Datuk Dr Maximus Ongkili was reported as saying that the Cabinet had agreed to continue the astronaut programme under the 10th Malaysia Plan (2011-2015).
However, no allocation has been set aside for the second mission as yet although allocations have been given for space training and education purposes.
Mustafa said he estimated that at least US$20 million (about RM62.5 million) was needed to fund the project.
He also said that Malaysia would have to launch another search for backup astronaut candidates once the second mission was launched.
Major Dr Faiz Khaleed, who was the backup astronaut for the first mission, has been named as the most potential astronaut for the second mission. | https://umno.info/2010/11/24/malaysia%E2%80%99s-second-space-mission-on-but-not-soon/ |
As in coppicing, the tradition of pollarding is to encourage the tree to produce new growth on a regular basis to maintain a supply of new wood for various purposes, particularly for fuel. In some areas, dried leafy branches are stored as winter fodder for stock. Depending upon the use of the cut material, the length of time between cutting will vary from one year for tree hay or withies, to five years or more for larger timber. Sometimes, only some of the regrown stems may be cut in a season – this is thought to reduce the chances of death of the tree when recutting long-neglected pollards.
Pollarding was preferred over coppicing in wood-pastures and other grazed areas, because animals would browse the regrowth from coppice stools. Historically, the right to pollard or "lop" was often granted to local people for fuel on common land or in royal forests; this was part of the right of Estover
Oskar Zapirain's photographs capture eerie forests cast in thick fog, hazy light descending upon the foliage in the same green shade that blankets the floor in moss. Zapirain has been attracted to this landscape for years because of the homogenous light as well as the way it forces the viewer directly into a mystical atmosphere.
The forest Zapirain features is a beech forest in Oiartzun, Basque Country in Northern Spain. This particular forest is unique due to the history charcoal production within the region. Instead of clearcutting like we do today, the trees were instead pruned to preserve the trees and maintain the integrity of the forest across generations. The trees have since regrown with short trunks and dramatically long limbs that shoot outward like arms from almost every angle, adding a ghostly feel to each of Zapirain’s photos. You can explore more of his work on Flickr. | https://offgridquest.com/green/foggy-forests-of-ancient-trees-pruned-fo |
SUMMARY: The Securities and Exchange Commission is adopting amendments to the registration form for insurance company separate accounts that are registered as unit investment trusts and that offer variable annuity contracts. The amendments revise the format of the fee table to require disclosure of the range of total expenses for all of the mutual funds offered through the separate account, rather than disclosure of the expenses of each fund. In addition, the Commission is amending the fee table of the registration form for variable life insurance policies to require disclosure of the range of total expenses of all of the mutual funds offered, consistent with the amendments to the fee table of the registration form for variable annuities.
Effective Date: December 23, 2002.
1. Initial Compliance Date: All new registration statements, and post-effective amendments that are annual updates to effective registration statements, filed on Form N-4 or Form N-6 on or after January 1, 2003, must comply with the amendments to Form N-4 or Form N-6, respectively.
2. Final Compliance Date: All insurance company separate accounts that are registered as unit investment trusts and that currently offer variable annuity contracts or variable life insurance policies with effective registration statements must comply with the amendments to Form N-4 or Form N-6, respectively, for post-effective amendments that are annual updates to their registration statements on Form N-4 or N-6 filed on or after January 1, 2003, and no later than January 1, 2004.
FOR FURTHER INFORMATION CONTACT: Katy Mobedshahi, Senior Counsel, (202) 942-0721, Office of Disclosure Regulation, Division of Investment Management, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0506.
SUPPLEMENTARY INFORMATION: The Securities and Exchange Commission ("Commission") is adopting amendments to Form N-4 [17 CFR 239.17b; 17 CFR 274.11c], the form used by separate accounts organized as unit investment trusts and offering variable annuity contracts to register under the Investment Company Act of 1940 [15 U.S.C. 80a-1 et seq.] ("Investment Company Act") and to offer their securities under the Securities Act of 1933 [15 U.S.C. 77a et seq.] ("Securities Act"). The Commission is also adopting amendments to Form N-6 [17 CFR 239.17c; 17 CFR 274.11d], the form used by separate accounts organized as unit investment trusts and offering variable life insurance policies to register under the Investment Company Act and to offer their securities under the Securities Act.
We received four comment letters on the proposed amendments.6 Two of the commenters supported the proposed requirement for disclosure of the range of expenses for all of the Portfolio Companies offered, while one commenter favored disclosure of the expenses of each Portfolio Company in the variable annuity prospectus.
We continue to believe that our approach will assist investors in understanding the fees and charges that they will pay for a variable annuity contract. The amendments will streamline the fee table in the contract prospectus and make it more understandable, while at the same time investors will continue to have access to information about the fees and expenses of each Portfolio Company. We recently amended Form N-1A, the form used by mutual funds to register under the Investment Company Act and to offer their securities under the Securities Act, to require that every mutual fund that offers its shares as an investment option for a variable annuity contract include a fee table in its prospectus.7 Investors in variable annuity contracts now have access to information about the fees and expenses of each Portfolio Company in the prospectus for the Portfolio Company.8 The amendments that we are adopting to the fee table of Form N-4 will require a statement referring investors to the Portfolio Company prospectuses for more detail concerning Portfolio Company fees and expenses. In addition, the requirement that the fee table of Form N-4 include the range of Portfolio Company expenses will clearly indicate to investors the maximum fees that may be charged by any of the Portfolio Companies offered, so investors will receive disclosure in the variable annuity contract prospectus of the highest possible amount of Portfolio Company expenses that they may pay.
We are adopting other amendments to the format and instructions for the fee table of Form N-4 substantially as proposed, with minor changes to address commenters' suggestions.
In response to a commenter's suggestion, we are modifying the Instructions to the expense example of Item 3(a) regarding conversion of annual contract fees to a percentage basis by providing that the total amount of the contract fees collected during the year should be divided by the total average net assets for the contract (which includes both general account and separate account assets), rather than only separate account assets, as we had proposed and as the instructions to Item 3(a) of Form N-4 currently require.18 This revision will result in a more accurate calculation of the annual contract fee percentage, by attributing the contract fee to both separate account and general account assets.
Requirement to Disclose All Fees and Charges. We are adopting, as proposed, an instruction to the fee table of Form N-4 that would require registrants to disclose all recurring fees and charges, including fees and charges for all optional features.20 One commenter suggested that we clarify the instruction requiring disclosure of all recurring fees and charges, to indicate that mutually exclusive fees (such as fees for mutually exclusive death benefit options) do not need to be presented in the fee table. We disagree with this approach because it would result in charges for some available features not being disclosed. As a result, investors who are considering these features would be unable to assess their cost. Registrants may, however, indicate, through a footnote or other means, that charges for certain features shown in the fee table are mutually exclusive. We note that registrants should not include multiple mutually exclusive fees in the expense example, but should include the highest of these charges. For example, if a contract offers two mutually exclusive death benefit options, with mortality and expense risk charges of 1.25% and 1.40%, respectively, the expense example should reflect a mortality and expense risk charge of 1.40%.
The effective date of these amendments is December 23, 2002. All new registration statements, and post-effective amendments that are annual updates to effective registration statements, filed on Form N-4 or N-6 on or after January 1, 2003, must comply with these amendments. The final compliance date for filing amendments to effective registration statements to conform to these amendments is January 1, 2004. A registrant may, at its option, comply with the requirements of these amendments to Forms N-4 and N-6 at any time after the effective date.
The Commission is sensitive to the costs and benefits imposed by its rules on affected persons and entities. In the Proposing Release, we requested comment and specific data regarding the costs and benefits of the proposed amendments, but received none.
Form N-4 is the registration form used by insurance company separate accounts organized as unit investment trusts that offer variable annuity contracts to register under the Investment Company Act and to register their securities under the Securities Act.24 Form N-4 requires that a prospectus for a variable annuity contract include a fee table showing the costs and expenses that a variable annuity contractowner will bear, directly or indirectly, including the annual operating expenses for each mutual fund in which a contractowner may invest ("Portfolio Company"). The amendments adopted today will revise the fee table in the prospectus of Form N-4 to require registrants to disclose the range of total expenses for all of the Portfolio Companies offered, rather than separately disclosing the fees and expenses of each Portfolio Company. Registrants will still be permitted to include additional disclosure of the fees and expenses of each Portfolio Company offered through a sub-account of the registrant. Use of a range of Portfolio Company expenses is warranted in order to streamline and improve fee tables for variable annuity contracts, which have grown increasingly longer and more complex in recent years as the number of investment options available through a typical variable annuity contract has expanded. In addition, the amendments that we are adopting include a conforming change to the fee table of Form N-6, to require disclosure of only the range of total expenses for all the Portfolio Companies, and not line item disclosure of the range of each category of expenses.
Revising the expense example in the fee table to require only an example based on the maximum expenses charged by any Portfolio Company.
Making other modifications to the format of the example.
Prescribing narrative explanations to precede each section of the fee table.
Adding an instruction requiring disclosure of all recurring fees and charges other than Portfolio Company operating expenses.
We believe that the amendments adopted today to Form N-4 will benefit investors by making the variable annuity prospectus easier for investors to understand. As noted above, disclosure of a range of Portfolio Company expenses should make fee tables for variable annuity contracts, which have grown increasingly longer and more complex in recent years, shorter and more comprehensible. Investors will continue to have access to information about the fees and expenses of each Portfolio Company in the prospectus for the Portfolio Company. The amendments will also modify the expense example of the Form N-4 fee table, consistent with the use of the range of Portfolio Company expenses in the fee table.
The amendments will make technical changes to the format and instructions of the fee table of Form N-4, in order to improve transparency of the fees and charges that contractowners will pay, to make the Form N-4 fee table more consistent with its counterpart in Form N-6, and to reflect changes in the types of fees and charges assessed by variable annuity contracts since the fee table of Form N-4 was adopted. We believe these changes may improve disclosure of variable annuity fees and expenses to investors. It is difficult to quantify the effects of this improved disclosure, though we note that the changes we are adopting are limited in nature.
In addition, conforming the disclosure requirements for Portfolio Company expenses in variable annuity prospectuses to those in variable life prospectuses may simplify the process of preparing registration statements for some registrants, because frequently insurance companies that issue variable annuities also issue variable life insurance.28 We believe that these cost savings will be relatively small, however.
Finally, the conforming amendments we are adopting to the fee table of Form N-6 will reduce the potential for confusion to investors that may occur if the disclosure of the range of minimum and maximum expenses for each category of Portfolio Company operating expenses results in two columns that do not add up to the range of minimum and maximum total operating expenses. This change will streamline the Form N-6 fee table, while continuing to ensure that investors have access to fee information about the Portfolio Companies in which they invest.
Although the amendments to the fee table of Form N-4 are limited and many of them are technical in nature, they differ from the current requirements of the fee table of Form N-4, which have been in place since 1989. Therefore, variable annuity issuers may incur a one-time cost for training in order for their personnel, particularly lawyers and others who are responsible for supervising the preparation of filings on Form N-4, to review and analyze the disclosure requirements of the amendments to Form N-4. Because the amendments will make mostly minor changes to the current format of the Form N-4 fee table, and will not require the disclosure of information that the current fee table does not require, we estimate that this cost will be fairly small. We lack data necessary to make a more precise estimate of the cost resulting from the amendments, but we estimate that this cost will be approximately $500 for each insurance company that sponsors separate accounts that are registered on Form N-4 and issue variable annuity contracts that are actively being sold. Further, we estimate that there are 94 such insurance companies.29 We therefore estimate the one-time cost attributable to the proposed amendments to Form N-4 to be $47,000. We requested comment on these cost estimates in the Proposing Release, but received none.
We do not expect that the amendments to Form N-4 will result in any net effect on the aggregate hour burden for completing and filing Form N-4. We expect that in preparing their fee tables for Form N-4, registrants will still need to collect information about the expenses for each Portfolio Company offered through the contract, in order to determine the minimum and maximum total operating expenses of the Portfolio Companies offered through the contract. We also expect that the other proposed amendments modifying the format and instructions of the Form N-4 fee table to conform more closely to the Form N-6 fee table will have no net effect on the burden hours for completing and filing Form N-4, because they will not require disclosure of any additional information by issuers.
Finally, we do not anticipate that the conforming changes we are making to the fee table of Form N-6 will result in any increased costs to issuers or investors. Issuers will be required to disclose only the range of total Portfolio Company operating expenses, rather than the range of each category of expenses as well as the range of total expenses. In addition, issuers have only recently begun using new Form N-6, or have not yet begun doing so. Therefore, any cost for training personnel to apply the amendment to the fee table of Form N-6 may be incorporated in the overall cost for training personnel in the disclosure requirements of Form N-6 as a whole.
Section 2(c) of the Investment Company Act, section 2(b) of the Securities Act, and section 3(f) of the Securities Exchange Act of 1934 require the Commission, when engaging in rulemaking that requires it to consider or determine whether an action is consistent with the public interest, to consider, in addition to the protection of investors, whether the action will promote efficiency, competition, and capital formation.30 The Commission has considered these factors. We requested comments regarding the effects of the proposed amendments on efficiency, competition and capital formation and received none.
The amendments to Form N-4 and Form N-6 are expected to have minimal effects on efficiency and competition among issuers of variable insurance products. As adopted, the amendments will revise the fee table in the prospectus of Form N-4 to require registrants to disclose the range of expenses for all the Portfolio Companies offered through the separate account, rather than disclosing separately the fees and expenses of each Portfolio Company. The amendments will make certain other technical changes to conform the format and instructions to the fee table of Form N-4 more closely to its counterparts in Form N-6 and Form N-1A. In addition, the amendments will revise the fee table of Form N-6 to require disclosure of the range of total expenses for all the Portfolio Companies offered, and not disclosure of the range of each category of Portfolio Company expenses, consistent with the amendments to the fee table of Form N-4. The amendments will allow fee table disclosure of Portfolio Company expenses in both Form N-4 and Form N-6 to be shorter, and generally make fee table disclosure clearer and more understandable to investors. However, we do not expect the amendments to have any significant effect on competition and efficiency because they will not change the quantity of information about fees and expenses that investors in variable annuity contracts receive. Similarly, it is unclear whether the amendments to Form N-4 and Form N-6 will affect capital formation.
As explained in the Proposing Release, certain provisions of Form N-4 contain "collection of information" requirements within the meaning of the Paperwork Reduction Act of 1995 [44 U.S.C. 3501 et seq.]. The title for the collection of information is "Form N-4 under the Investment Company Act of 1940 and Securities Act of 1933, Registration Statement of Separate Accounts Organized as Unit Investment Trusts." The information collection requirements imposed by Form N-4 are mandatory. Responses to the collection of information will not be kept confidential. An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid control number.
We published a notice soliciting comments on the collection of information requirements of Form N-4 in the Proposing Release. The Commission did not receive any comments on the Paperwork Reduction Act portion of the Proposing Release.
Form N-4 (OMB Control No. 3235-0318) was adopted pursuant to section 8(a) of the Investment Company Act [15 U.S.C. 80a-8] and section 5 of the Securities Act [15 U.S.C. 77e].31 As stated above, the purpose of Form N-4 is to meet the registration and disclosure requirements of the Securities Act and Investment Company Act and to enable separate accounts organized as unit investment trusts that offer variable annuity contracts to provide investors with information necessary to evaluate an investment in a variable annuity contract.
The Commission proposed to amend Form N-4 to conform the disclosure of Portfolio Company expenses in the fee table to the format used in Form N-6, the registration form for insurance company separate accounts registered as unit investment trusts that offer variable life insurance policies. Under the proposed amendments, registrants on Form N-4 will be required to disclose only the range of the expenses for all of the Portfolio Companies in which the separate account invests. Variable annuity investors will continue to have access to complete information about the Portfolio Company fees and expenses because disclosure of the fees and expenses for each Portfolio Company will be included in its prospectus under the requirements of Form N-1A. The amendments will also make other technical changes in order to conform the format and instructions for the fee table of Form N-4 to its counterparts in Form N-6 and Form N-1A.
We do not expect that the amendments to Form N-4 will result in any net effect on the aggregate hour burden for completing and filing Form N-4, and therefore the amendments to Form N-4 will not impose any additional collection of information on registrants. We expect that in preparing their fee tables for Form N-4, registrants will still need to collect information about the total operating expenses for each Portfolio Company offered through the contract, in order to determine the minimum and maximum expenses of the Portfolio Companies. We also expect that the other amendments modifying the format of the Form N-4 fee table to conform more closely to the fee tables of Forms N-6 and N-1A will have no net effect on the burden hours for completing and filing Form N-4, because they will not require any additional information to be disclosed.
In addition, we expect that the conforming amendments we are adopting to Form N-6, the registration form for insurance company separate accounts that are registered as unit investment trusts and that offer variable life insurance policies, requiring disclosure of only the range of total expenses for all of the Portfolio Companies offered through the separate account rather than line item disclosure of the range of each category of expenses as well as the range of total expenses, will have no effect on the burden of completing Form N-6. Form N-6 already requires variable life insurance issuers to calculate the range of total expenses for each Portfolio Company offered through a variable life insurance policy, and therefore the amendments will not impose any additional costs on issuers.
Pursuant to Section 605(b) of the Regulatory Flexibility Act [5 U.S.C. 605(b)], the Chairman of the Commission has certified that the proposed amendments to Form N-4 would not, if adopted, have a significant economic impact on a substantial number of small entities. The initial certification was attached to the Proposing Release as Appendix A. We requested comments on the certification, but received none.
Pursuant to Section 605(b) of the Regulatory Flexibility Act [5 U.S.C. 605(b)], the Commission certifies that the amendments to Form N-6 adopted as part of this Adopting Release will not have a significant economic impact on a substantial number of small entities. The amendments will revise the fee table of Form N-6 to require only disclosure of the range of total expenses for all of the Portfolio Companies offered through a variable life insurance policy, rather than line item disclosure of the range of each category of expenses as well as the range of total expenses. The economic impact of the amendments will not be significant. Form N-6 already requires variable life insurance issuers to calculate the range of total expenses for each Portfolio Company offered through a variable life insurance policy, and therefore the amendments will not impose any additional costs on issuers.
The amendments to Form N-4 and Form N-6 are being adopted pursuant to sections 5, 7, 8, 10, and 19(a) of the Securities Act [15 U.S.C. 77e, 77g, 77h, 77j, and 77s(a)] and sections 8, 24, 30, and 38 of the Investment Company Act [15 U.S.C. 80a-8, 80a-24, 80a-29, and 80a-37].
For the reasons set out in the preamble, the Commission amends Chapter II, Title 17 of the Code of Federal Regulations as follows.
Section 274.101 is also issued under secs. 3(a) and 302, Pub. L. No. 107-204, 116 Stat. 745.
h. Adding new Instructions 17 through 22.
Note: The text of Form N-4 does not and these amendments will not appear in the Code of Federal Regulations.
The following tables describe the fees and expenses that you will pay when buying, owning, and surrendering the contract. The first table describes the fees and expenses that you will pay at the time that you buy the contract, surrender the contract, or transfer cash value between investment options. State premium taxes may also be deducted.
The next table describes the fees and expenses that you will pay periodically during the time that you own the contract, not including [portfolio company] fees and expenses.
The next item shows the minimum and maximum total operating expenses charged by the portfolio companies that you may pay periodically during the time that you own the contract. More detail concerning each [portfolio company's] fees and expenses is contained in the prospectus for each [portfolio company].
This Example is intended to help you compare the cost of investing in the contract with the cost of investing in other variable annuity contracts. These costs include contract owner transaction expenses, contract fees, separate account annual expenses, and [portfolio company] fees and expenses.
1. Include the narrative explanations in the order indicated. A Registrant may modify a narrative explanation if the explanation contains comparable information to that shown.
3. A Registrant may omit captions if the Registrant does not charge the fees or expenses covered by the captions. A Registrant may modify or add captions if the captions shown do not provide an accurate description of the Registrant's fees and expenses.
5. In the Contractowner Transaction Expenses, [Annual] Contract Fee, and Separate Account Annual Expenses tables, the Registrant must disclose the maximum guaranteed charge, unless a specific instruction directs otherwise. The Registrant may disclose the current charge, in addition to the maximum charge, if the disclosure of the current charge is no more prominent than, and does not obscure or impede understanding of, the disclosure of the maximum charge. In addition, the Registrant may include in a footnote to the table a tabular, narrative, or other presentation providing further detail regarding variations in the charge. For example, if deferred sales charges decline over time, the Registrant may include in a footnote a presentation regarding the scheduled reductions in the deferred sales charges.
15. If the Registrant (or any other party pursuant to an agreement with the Registrant) imposes any other recurring charge other than annual portfolio company total operating expenses, add another caption describing it and list the (maximum) amount or basis on which the charge is deducted.
17. (a) If a Registrant has multiple sub-accounts, it should disclose the minimum and maximum "Total Annual [Portfolio Company] Operating Expenses" for any portfolio company. "Total Annual [Portfolio Company] Operating Expenses" include all expenses that are deducted from a portfolio company's assets. The amount of expenses deducted from a portfolio company's assets are the amounts shown as expenses in the portfolio company's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]).
(b) "Total Annual [Portfolio Company] Operating Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred by any portfolio company that would, if included, materially affect the minimum or maximum amounts shown in the table, disclose in a footnote to the table what the minimum and maximum "Total Annual [Portfolio Company] Operating Expenses" would have been had the extraordinary expenses been included.
18. (a) Base the percentages of "Total Annual [Portfolio Company] Operating Expenses" on amounts incurred during the most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If a portfolio company has a fiscal year different from that of the Registrant, base the expenses on those incurred during either the period that corresponds to the fiscal year of the Registrant, or the most recently completed fiscal year of the portfolio company. If the Registrant or a portfolio company has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Total Annual [Portfolio Company] Operating Expenses."
(ii) In a footnote to the table, disclose that the expense information in the table has been restated to reflect current fees.
(c) A change in "Total Annual [Portfolio Company] Operating Expenses" means either an increase or a decrease in expenses that occurred during the most recent fiscal year or that is expected to occur during the current fiscal year. A change in "Total Annual [Portfolio Company] Operating Expenses" does not include a decrease in operating expenses as a percentage of assets due to economies of scale or breakpoints in a fee arrangement resulting from an increase in a portfolio company's assets.
19. A Registrant may reflect minimum and maximum actual total [portfolio company] operating expenses that include expense reimbursement or fee waiver arrangements in a footnote to the table. If the Registrant provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, or whether it can be terminated at any time at the option of a portfolio company.
20. A Registrant may include additional tables showing annual operating expenses separately for each portfolio company immediately following the required table of "Total Annual [Portfolio Company] Operating Expenses." The additional tables should be prepared in the format, and in accordance with the Instructions, prescribed in Item 3 of Form N-1A [17 CFR 239.15A; 17 CFR 274.11A] for disclosing "Annual Fund Operating Expenses."
(i) Include in the Example the information provided by the caption "If you annuitize at the end of the applicable time period" only if the Registrant charges fees upon annuitization that are different from those charged upon surrender.
(a) Base the percentages in "Total Annual [Portfolio Company] Operating Expenses" on payments that will be made, but include in expenses amounts that will be incurred without reduction for expense reimbursement or fee waiver arrangements, estimating amounts of expenses that are not established pursuant to contract. Disclose in a footnote to the table that "Total Annual [Portfolio Company] Operating Expenses" are based, in part, on estimated amounts for the current fiscal year.
(b) A New Registrant may reflect in a footnote to the table expense reimbursement or fee waiver arrangements that are expected to reduce the minimum and/or maximum total [portfolio company] operating expenses shown in the table. If the New Registrant provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, or whether it can be terminated at any time at the option of a portfolio company.
(c) Complete only the 1- and 3-year period portions of the Example, and estimate any [annual] contract fees collected.
b. Revising Instructions 4 and 5.
Note: The text of Form N-6 does not and these amendments will not appear in the Code of Federal Regulations.
The following tables describe the fees and expenses that you will pay when buying, owning, and surrendering the Policy. The first table describes the fees and expenses that you will pay at the time that you buy the Policy, surrender the Policy, or transfer cash value between investment options.
The next table describes the fees and expenses that you will pay periodically during the time that you own the Policy, not including [Portfolio Company] fees and expenses.
4. Total Annual [Portfolio Company] Operating Expenses.
(a) The Registrant may substitute the term used in the prospectus to refer to the Portfolio Companies for the bracketed portion of the caption provided.
(b) If a registrant has multiple sub-accounts, it should disclose the minimum and maximum "Total Annual [Portfolio Company] Operating Expenses" for any Portfolio Company. "Total Annual [Portfolio Company] Operating Expenses" include all expenses that are deducted from a Portfolio Company's assets. The amount of expenses deducted from a Portfolio Company's assets are the amounts shown as expenses in the Portfolio Company's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]).
(c) "Total Annual [Portfolio Company] Operating Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred by any Portfolio Company that would, if included, materially affect the minimum or maximum amounts shown in the table, disclose in a footnote to the table what the minimum and maximum "Total Annual [Portfolio Company] Operating Expenses" would have been had the extraordinary expenses been included.
(d)(i) Base the percentages of "Total Annual [Portfolio Company] Operating Expenses" on amounts incurred during the most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If a Portfolio Company has a fiscal year different from that of the Registrant, base the expenses on those incurred during either the period that corresponds to the fiscal year of the Registrant, or the most recently completed fiscal year of the Portfolio Company. If the Registrant or a Portfolio Company has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Total Annual [Portfolio Company] Operating Expenses."
(B) In a footnote to the table, disclose that the expense information in the table has been restated to reflect current fees.
(iii) A change in "Total Annual [Portfolio Company] Operating Expenses" means either an increase or a decrease in expenses that occurred during the most recent fiscal year or that is expected to occur during the current fiscal year. A change in "Total Annual [Portfolio Company] Operating Expenses" does not include a decrease in operating expenses as a percentage of assets due to economies of scale or breakpoints in a fee arrangement resulting from an increase in a Portfolio Company's assets.
(e) A Registrant may reflect minimum and maximum actual total [Portfolio Company] operating expenses that include expense reimbursement or fee waiver arrangements in a footnote to the table. If the Registrant provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, or whether it can be terminated at any time at the option of a Portfolio Company.
(f) A Registrant may include additional tables showing annual operating expenses separately for each Portfolio Company immediately following the required table of "Total Annual [Portfolio Company] Operating Expenses." The additional tables should be prepared in the format, and in accordance with the Instructions, prescribed in Item 3 of Form N-1A [17 CFR 239.15A; 17 CFR 274.11A] for disclosing "Annual Fund Operating Expenses."
1 Item 3(a) of Form N-4.
2 Variable annuity separate accounts registered as unit investment trusts are divided into sub-accounts, each of which invests in a different Portfolio Company. Each contractowner selects the sub-accounts, and thus the Portfolio Companies, in which his or her account value is invested. A "Portfolio Company" may be a registered investment company, or a series of a registered investment company, in the case of a series company.
3 Investment Company Act Release No. 25521 (Apr. 12, 2002) [67 FR 19886, 19886 (Apr. 23, 2002)].
4 Rick Carey, 9-Month Variable Annuity Sales Fell 17.8% To $113 Billion Last Year, National Underwriter Life & Health/Financial Services Edition, March 11, 2002, at 16 (estimating that average number of funds available in a variable annuity contract increased from five in 1988 to 33 in 2001).
5 Timothy C. Pfeifer, Growing Rider Use Furthers Flexibility But Also Complexity, National Underwriter Life & Health/Financial Services Edition, Sept. 3, 2001, at 22 (describing growth in optional riders on both variable annuities and variable life insurance).
6 The comment letters and a summary of comments prepared by our staff are available for public inspection and copying in the Commission's Public Reference Room, 450 Fifth St., N.W., Washington, D.C. 20549, in File No. S7-07-02. Public comments submitted electronically and a summary of comments are also available electronically on our website at www.sec.gov.
7 Investment Company Act Release No. 25522 (Apr. 12, 2002) [67 FR 19847, 19860 (Apr. 23, 2002)] ("N-6 Adopting Release"); Item 3 of Form N-1A. Prior to this amendment, a mutual fund that offered its shares exclusively as investment options for variable life insurance policies and variable annuity contracts was permitted to omit the fee table from its prospectus. See Investment Company Act Release No. 16766 (Jan. 23, 1989) [54 FR 4772 (Jan. 31, 1989)] (adopting Form N-4 fee table and eliminating the fee table requirement in Form N-1A for Portfolio Companies offering shares exclusively to insurance company separate accounts).
8 Investors in variable annuity contracts receive the prospectuses for both the separate account unit investment trust and the Portfolio Companies they have selected.
9 Instruction 20 to Item 3(a) of Form N-4; Instruction 4(f) to Item 3 of Form N-6.
10 Item 3(a) and Instruction 17(a) to Item 3(a) of Form N-4.
11 Item 3(a) of Form N-4. If none of the Portfolio Companies offered by a variable annuity contract charge distribution (12b-1) fees, the reference to these fees may be omitted.
12 Item 3 and Instructions 4 and 5 to Item 3 of Form N-6.
13 Proposing Release, supra note 3, 67 FR at 19888.
14 Instructions 18(a), 19, and 22(a) to Item 3(a) of Form N-4. We intend that the staff construe the amendments to the fee table of Form N-4 consistent with the approach taken under Form N-1A, to permit the addition of one line to the fee table showing the range of net Portfolio Company operating expenses after taking account of contractual limitations that require reimbursement or waiver of expenses. This additional line would be placed immediately under the "Total Annual [Portfolio Company] Operating Expenses" line of the fee table and would have to use appropriate descriptive captions. A footnote to the fee table would be required to describe the contractual arrangement. See Proposing Release, supra note 3, 67 FR at 19887 n.15.
15 Instruction 21(b) to Item 3(a) of Form N-4. Under Form N-1A, the staff has permitted mutual funds with fees that are subject to a contractual limitation that requires reimbursement or waiver of expenses to take account of the reimbursement or waiver in calculating the example required by the fee table of Item 3, but only for the duration of the contractual limitation. Funds may not assume that the reimbursement or waiver will continue for periods subsequent to the contractual limitation period in calculating expenses shown in the example. Cf. Letter from Barry D. Miller, Associate Director, Division of Investment Management, SEC, to Craig S. Tyle, General Counsel, Investment Company Institute (Oct. 2, 1998) (permitting funds with fees that are subject to a contractual limitation that requires reimbursement or waiver to add two lines to the fee table showing the amount of the reimbursement or waiver and total net expenses). We intend that the staff construe the amendments to the expense example requirements of Form N-4 consistent with the approach it has taken with the expense example of the fee table of Form N-1A, to permit expense examples to take into account contractual limitations on Portfolio Company operating expenses that require reimbursement or waiver of expenses, but only for the period of the contractual limitation.
16 Instruction 21(b) to Item 3(a) of Form N-4.
18 Instruction 21(f) to Item 3(a) of Form N-4; Instruction 21(e) to Item 3(a) of current Form N-4.
19 Item 3(a) and Instructions 21(a) and (b) to Item 3(a) of Form N-4.
20 Instruction 15 to Item 3(a) of Form N-4.
21 See supra note 7 and accompanying text.
22 N-6 Adopting Release, supra note 7, 67 FR at 19860 (discussing compliance date for amendment to Form N-1A).
23 Id. at 19860 n.83.
24 Under a variable annuity contract, purchase payments are invested in an insurer's separate account created under state law and legally segregated from the assets of the insurer's general account. The separate account offers the contract owner a number of investment options, which generally consist of mutual funds.
25 The amendments will require a registrant to include a statement referring investors to Portfolio Company prospectuses for more detail concerning Portfolio Company fees and expenses. This required statement would not impose any additional disclosure burden on registrants, because the instructions to Form N-4 currently require a similar cross-reference to the Portfolio Company prospectuses. See General Instruction 1 to Item 3(a) of current Form N-4.
26 An insurance company that issues variable annuities provided the staff with estimates of the typical print run of a prospectus and the associated printing and mailing costs.
27 The estimate of 814 variable annuity contracts is based on the number of contracts tracked by Morningstar, Inc. Morningstar, Principia Pro Plus, Variable Annuities/Life (May 2002). While Morningstar tracks a substantial majority of variable annuity contracts, it does not track all existing contracts.
28 We estimate, based on an analysis of data from the EDGAR filing system for 2000 and 2001, that approximately two-thirds of insurers issuing variable annuities also issue variable life insurance policies.
29 The estimate of the number of insurance companies issuing variable annuities is based on the staff's analysis of data from the EDGAR filing system for 2000 and 2001.
30 15 U.S.C. 77b(b), 78c(f), and 80a-2(c).
31 OMB approved the collection of information requirements contained in Form N-6 (OMB Control No. 3235-0503). The title for the collection of information is "Form N-6 Under the Investment Company Act of 1940 and the Securities Act of 1933, Registration Statement of Variable Life Insurance Separate Accounts Registered as Unit Investment Trusts." | https://www.sec.gov/rules/final/33-8147.htm |
I always wanted to travel across the United States and take one of these American classic road trips, but I had no idea this will happen so unexpectedly this year.
After moving to Germany, and some short trips around Berlin and some others in Europe, I’ve been dreaming of spending this year summer holiday somewhere on the beach, just enjoying the sun and, eventually, discover the local lifestyle, while I can simply give myself enough time to relax and feel the summer vibes.
But, one day, we found some cheap plane tickets, Berlin – San Francisco and suddenly, we forgot about everything else and start dreaming about a road trip that could be our greatest journey so far: a road trip in California!
We traveled for 19 days across California and I can assure you, the US is the absolute best country for road tripping.
Here are a few things you should keep in mind as you plan your California road trip (there are also basic tips that can help you when you are planning long road trips):
Planning a road trip in California
1. How long before you should start planning the road trip?
If you are going to take a long trip, definitely you need to plan in advance. We had two months for planning after we found the plane tickets, and it was more than enough. But, for sure, the more time (and energy for doing this) you have, the more you can read, plan, and discover points of interest you do not want to miss.
2. Choosing the route
The ideal way to experience California is to hit the road because that’s how you can fully taste its spirit. The “sunshine state” has everything: scenic roads, amazing beaches, natural parks, historical landmarks, bustling cities. Are you after the ocean and the south laid-back atmosphere? The mountains are calling you and want to spend few days in the wilderness? Want to try your luck in Vegas? History is your thing? Regardless of the answer, California has it all. But, funny as it is, that can be a problem. There are countless things to see and do, but, unfortunately, you can’t say the same thing about your time and budget. So, before embarking on the journey, you have to decide what you really want not to miss.
Not sure where you want to go or what to see? Take a look at our route:
- Day 1: Arrival in San Francisco, overnight stop in Cupertino
- Day 2: Cupertino to Los Angeles, with stops in Half Moon Bay, Santa Cruz, and Monterey
- Days 3 – 4 – 5: Los Angeles, Santa Monica, Malibu, Venice
- Day 6: Los Angeles to Las Vegas (also Route 66)
- Days 7 – 8 – 9: Las Vegas and Grand Canyon
- Day 10: Las Vegas to Bishop (through Death Valley)
- Day 11: Bishop / Lone Pine
- Day 12: Bishop to Mariposa (Yosemite)
- Days 13 – 14: Yosemite
- Day 15: Yosemite to San Francisco
- Days 16 – 17 – 18 – 19: San Francisco
But there are also a lot of alternatives, depending on your preferences, time, budget and type of experiences you are looking for:
Alternative routes for a California Road Trip
- A Coastal California Road Trip: San Diego – Los Angeles – Santa Barbara – Monterey & Carmel – Santa Cruz – San Francisco
- Discover National Parks: San Francisco – Yosemite – Lake Tahoe – Redwood National Park – Muir Woods – San Francisco
- From beaches to the mountains: Los Angeles – San Diego – Palm Springs – Joshua Tree National Park – Death Valley – Mammoth Lakes – Yosemite – San Francisco
Online Tools for Planning a Road Trip
If you need extra help, you can try one of these online tools for planning your road trip:
- Road Trip USA – you’ll find cross-country routes and road-tested advice for adventurers
- Furkot.com – plan the route, find accommodation and suggestions for sightseeing along the route you chose
- Roadtrippers.com – plan the route, explore amazing places, road trips guides
- Tripit.com – road trip planner with stops
- RoadtripAmerica.com – helps you to plan your road trips and share your roadtripping passion and expertise with others
- Myscenicdrives.com – pre-planned scenic routes highlighting captivating places of interest with a feature-rich road-trip planner.
3. Book your flight
Generally, flights from Europe to the USA are pretty expensive. But if you constantly check for deals (and you’re a little lucky), you can find money-saving tickets. Anyway, make sure to book your flight as early as you can, at least two or three months in advance. We found an amazing cheap airfare, only 370 EUR from Berlin to San Francisco, with Lufthansa, two months before our departure.
Where you can search for flight fares
And some bonus tips:
Be flexible with dates – flying in the middle of the week is way cheaper than flying on weekends;
Use more airline search websites, because sometimes they can provide you different prices for the same flight, or they don’t always include all the budget airlines.
If you’re flying with a low-cost company, pay attention to all the possible costs they can add to your basic ticket (luggage, fees for selecting seats, fees for paying with credit card etc)
Choose the aisle seat instead of the window seat! For the long flights, this is the best option for me, cause I need to move from time to time (at least at two hours), and like this, there’s no need to disturb the other person sitting next to me.
4. Book your Accommodation
Hotels, motels, inns, camping, Airbnb, whatever you choose, book in advance. You can also add changes to your route taking into account accommodation prices. For example, we chose to stay in San Francisco at the end of our trip, because that was the time when the hotel prices were the lowest.
Tips:
If for whatever reason, it happens to have no accommodation for the night to come, and you don’t want to pay a fortune, use Hotel Tonight – an app that lets you book hotel rooms on the same day and at attractive rates (for iPhone only).
Book a hotel that has breakfast included. Even if you’re not a big fan of breakfast, like me (I usually get hungry in the “morning”, just after 11 o’clock), traveling all day can change things out, and a healthy breakfast in the morning will fuel you up for many hours.
Where to search for accommodation:
- Booking.com
- Airbnb.com
We loved staying at:
- Hard Rock Cafe Hotel – Las Vegas
- The Monarch Inn – Mariposa
- Fusion Hotel – San Francisco
5. Rent your Car
For sure the car is one of the most important things to consider when you’re thinking about a road trip. So, rent a car before you go, and be sure to choose something appropriate for all kind of roads.
Where to rent your car:
- Rentalcars.com
- Sixt.com
- Herz.com
6. Other bookings you should consider
After you’re done with all the essential bookings, take time to review some events that are going to happen during your road trip in one of your stops (festivals, concerts or any other kind of event you want to attend); it could be a good chance to buy tickets in advance and kill two birds with one stone. Furthermore, there are special tours or museums that require ahead of time bookings. Ice Cream Museum in San Francisco was completely sold out for the next 3 days, and to find a ticket for the night tours on Alcatraz (which I highly recommend), you need to reserve your entrance with at least 1 week before as well.
There are a lot of things to take into consideration when you start planning a road trip in California and, at the beginning, all this can seem a bit overwhelming. Be sure not to miss anything important in the planning phase and do some research about the things you want to see. But also keep loose plans, because you never know when other interesting things will arise. And, most of all, just enjoy the experience! Whatever route you’ll choose, I can assure you, a California road trip will be one of your life top experiences! | http://faraway.life/2017/11/07/how-to-plan-a-road-trip-in-california/ |
We won’t get into the aftermath of the stage 2 TTT, @LaVelocipede has summed up our thoughts perfectly here, but as expected the TTT has completely ripped up the GC race with Valverde sitting pretty with a two second lead over Van Garderen, Dennis and Hermans. Thomas, Landa and Froome are forty-six seconds behind the Movistar rider, Contador and Mollema are one minute fifteen seconds back and Yates sitting at one minute twenty-four seconds behind. This is where we’ll draw a line and say anyone under this won’t now be in contention for the overall. That means Kruijswijk (one minute forty-eight seconds), Martin (two minutes thirteen seconds), Bardet (two minutes fifteen seconds) and Majka (two minutes twenty-seven seconds and Zakarin (two minutes forty-eight seconds) are pretty much out of the running.
EDIT: Before the start of stage 3 the race organisers announced that they had penalised the whole of the Movistar team with a one-minute penalty. So the revised stage and GC placing are listed here. This means that Valverde isn’t now in as advantages position as we originally thought, so bear that in mind as you read on through the stage preview!
Regardless of the GC standings, we expect all of these riders to be in the mix in stage 3, which is the first of two summit finishes. The stage has four categorised climbs, with three of them coming in the last third of the stage, finishing with a double ascent up to the ski resort of La Molina.
The race starts with a cat three lump which will allow a break to get away and it’s pretty much uphill all day. Movistar will do sweet F.A. about bringing the break back as Valverde just needs to follow any attacks from his nearest rivals and sit on their wheels. So it will be up to Sky, Trek-Segefredo and Orica-Scott to chase the break down. We’d expect the to ramp up the pace on the first cat 1 climb, the Puerto de Toses, which isn’t a smooth, gradual gradient. It starts off at 3-4%, then flattens out, then pitches back up to 5% and then ramps up to 14% in the final km. If the riders are going to shake of Valverde it will be here, but it will be tough!
After this, the final 48km of the stage takes in two accents up to La Molina, the same as last year and previous editions. The climb itself is short and has an average of 5.8% with peaks at 9%. After the second ascent, they will climb for a further 2km and this will be the scene of a last ditch attempt to snatch back some time for Valverde’s pursuers. The final few hundred metres are a descent to the line.
We mentioned above that we expect all the main GC contenders to be at the sharp end of the stage and last year’s winner here, Dan Martin will be looking for a repeat success, especially given the fact he’s far down in the GC. But Alejandro Valverde will be looking to extinguish any hope his rivals have of clawing back even a few seconds, so if Movistar has staved off the attacks then expect them to deliver him to the final ascent of La Molina to go with the stage win and the bonus seconds on offer. Adam Yates should also go well and try and match his brother’s stage win at Paris-Nice. In terms of non-GC contenders, the likes of Brenden Canty or Micheal Woods of Cannondale Drapac would suit this finish, and a win would most certainly suit their team at the moment! Darwin Atapuma has done very little so far this season and will need to start to show his new team some sort of return. Finally, you can’t not mention Thomas De Gent on a stage like this, but we think he may be eyeing the queen stages on stage 5, as he did last year.
Our Pick: Adam Yates to continue the World Tour sibling rivalry and gain back some bragging rights.
Winner: Alejandro Valverde (Adam Yates 3rd)
Overall Preview
| |
The Normal Parks and Recreation Department features 18 playgrounds located in parks and close by Town Facilities throughout the community. Each play structure is unique in its target age and amenities featured. Whether your child likes slides, swings, monkey bars, climbing structures or just about anything - we've got you covered!
We provide citizens and visitors with a clean, safe, well-managed, fiscally sound and environmentally pleasant community.
Welcome to the Town of Normal, Illinois! A vibrant Midwestern community located in Central IL & home to Illinois State University, Rivian Automotive, Heartland Community College & Carle BroMenn. | https://normalil.gov/1508/Playgrounds |
I primarily help companies to identify new opportunities, to evaluate the business case and to plan for implementation. My outsider's perspective complements the internal business expertise of client teams. My engineering background provides the technical and procedural underpinning to these projects, in order to produce commercially viable strategies.
I add significant leverage to company-teams helping them to:
- gain familiarity very quickly with the issues and dynamics of the M2M/IoT market.
- explore innovative service concepts and go-to-market strategies that extend beyond existing company approaches.
- qualify new opportunities based on qualitative filters (competencies, key resources, strategic fit etc.) and quantitative analysis (market sizing, business case etc.).
- manage business risks through critical feedback on strategy, product and marketing plans.
Please contact me at [email protected] for further information.
RECENT PROJECTS
IoT Platform Strategy – IoT device and service providers recognize the need for connectivity- and application enablement platforms to optimize the user-experience and deliver high levels of service quality. This project, for a US technology firm, focused on strategic changes in the IoT platforms market, and especially the importance of inter-operability across different vendor products, to launch a new product and partner-collaboration strategy.
M2M Industry and Market Development - Between 2008 and 2012, I worked with strategy and go-to-market teams in the GSM Association to devise and launch a market development strategy to steer a path for the mobile industry, beyond M2M, into the wider connected devices market.
New Product Development (IoT Service Opportunities) - I worked with a major European mobile network operator (MNO) to short-list and then develop an initial strategy for new IoT services, about 12-18 months prior to launch.
IoT Operations and Service Strategy – This project, for a major US supplier of hardware and technology, assessed the emerging demand for operational support of enterprise M2M and emerging IoT services. This assessment fed into a business-unit strategy including key capability development goals and partnering opportunities.
Digital Currency and Mobile Payment Platform Strategy – I advised on a strategy to promote a next-generation payments-platform using mobile as a distribution channel for digital currencies. My work focused on the eco-system necessary to implement such a platform. I also outlined a multi-party business model and quantified the profitability outcomes necessary to incentivize each of the different partners in the value chain.
Competitive Dynamics for User-authentication Services – There is a growing tendency to use social-network login procedures as a mechanism for user-authentication. For this project, I analysed feedback from corporate users and developers of authentication systems to assess the relative market share of different approaches. The survey data also characterized the commercial criteria that buyers and developers wished to see in second-generation authentication solutions.
Off-Net M2M Strategy - This project, for a mobile network operator (MNO), evaluated the addressable market opportunity and recommended a channel strategy to target "off-net" M2M opportunities in countries adjoining the MNO's footprint. | http://www.more-with-mobile.com/p/services.html |
Thermwood has a strong commitment to advanced technology. It develops, manufactures and distributes technology based products, software, equipment and services for the manufacturing sector. It sells its products primarily as all-inclusive systems targeting specific customer applications and offers complete packages for many familiar industrial applications. Thermwood works closely with each customer and their application to find the best machine product and support technology and then provides extensive guidance, support, training and ongoing service.
Thermwood is also the US distributor for Fravol Edge Banders, making them the only CNC router manufacturer that can supply and service all the major software and equipment needed by custom cabinet shops.
Thermwood is an international company with sales and service in 35 industrialized countries. | http://www.thermwood.com/header/header7.htm |
Who knew science could be so much fun?? This past term one of my courses was Bloodstain Pattern Analysis. I know, I know – you’re asking, “There’s actually enough to this to make an entire course out of it?” and my answer is “Yes!” We used a textbook and everything!
There’s really enough information for more than one class, but one is all I got. In any case, I had no idea all of the things that this specialty can tell an analyst. Interesting? Definitely. Informative? Absolutely. Gruesome? Perhaps, but remember, as crime scene investigators, we are looking for anything that can tell us what happened. We are trying to recreate the scene – put the pieces of the puzzle together, so to speak. Everything from fingerprints to trace evidence to blood can speak volumes. So we’re looking at the blood not as some freakish special effect from a horror movie, but as a puzzle piece. However, if you have a weak stomach you may want to stop reading. Or just skip the pictures.
Forgive me for working in reverse here, but I’m playing catch-up because I let so much time lapse and didn’t post regularly when I should have. I’m going to start with what constituted as our final: a case study and a partial re-enactment of two actual crimes that my professor investigated when he was a homicide detective. They both involved bludgeoning cases; one where there was relatively little bloodstain evidence, and the other where the victim sustained over thirty blows to the head with a hammer and there was an overwhelming amount of blood on the scene, as you can imagine. We concentrated on the second case.
Here, the prime suspect was the victim’s husband. When he woke up in the hospital after having tried to commit suicide by swallowing anything he could get his hands on before the police showed up (including bleach) while his wife was bleeding to death on the floor, he claimed that it was self-defense: she had come at him with a pot of rice that had been cooking, as well as a knife, and he had several (very superficial) knife wounds on his chest “to prove she attacked him”. I guess she was pretty scary to merit all that head trauma… oops, I mean… our job as investigators is not to judge. Or assume. Just to collect and analyze facts. Ahem.
As a class we studied photos of the scene. They showed clearly that the attack was confined to the kitchen, and that the largest area of blood spatter was concentrated on the lower front of the dishwasher. The attack must have involved her being close to the ground. While we didn’t see pictures of his clothing, my professor explained that her blood was found on the back and even on the inside of the lower legs of his pants.
Next came the recreation. Could we effectively re-enact the crime in order to study the blood stains and what they may tell us? Well, we could sure try. Materials needed: dropcloths, painter suits, a hammer, foam core boards to prop against the wall, two heavy plaster “heads” called Splatter Heads (I’m not making this up, folks – see pic)with flat surfaces to hold “bladders” filled with sheep blood,and two guinea pigs, I mean students, to serve as the suspects. One of the heads was positioned a few feet away from the foam core on the wall. After being suited up and duct taped to protect clothing and body parts from flying blood drops, the first suspect was free to beat on the Spatter Head. We counted his blows… up to 40 of them… and then stood back to admire the damage. See pictures…
The spatter on the wall from Suspect No. 1 sure didn’t resemble the overwhelming amount of blood seen in the actual crime scene photos. There wasn’t nearly as much and the patterns were different. But taking into consideration that the actual victim was moving at the time, and that our Suspect No. 1 was not swinging with force (in an effort to save the classroom and himself from being covered in sheep’s blood) the resulting stains could be somewhat understandable. However, what should be noted is the back spatter on his clothing and just how much of the victim’s blood would be found on him – patterns can clearly be distinguished from the way he was kneeling and the way the clothing was bunched. But it was confined mostly to the front of him. The actual case suspect had blood droplets on the back (and inside) of his jeans. Why?
On to Suspect No. 2. In this case the Spatter Head was moved to within inches of the wall. And this “suspect” didn’t hold back. A softball player in “real life”, Kristen swung at the head with the force of a ball player in the last inning of the World Series. Her swings were much more extended and powerful, and the resulting spatter of thirty-some hits showed it.
This looked MUCH closer to the actual crime scene, proving that at some point during the crime, the victim was on her knees inches from the dishwasher. The blows she sustained were powerful and strong. And unlike with Suspect No. 1, Kristen also had blood drops on her back – she was swinging wider and harder – the drops came from the hammer cast off backwards. In addition, the detectives at the actual scene determined that the blood on the inside of the suspect’s pant legs came from the fact that they had been rolled up at the time of the crime, exposing the inside fabric.
Studying the spatter closer, my professor pointed out areas within the overall staining that showed individual blows. We could also see areas that had a pinkish hue, called atomized blood or misting – which often results from what’s known as high-velocity impact spatter, seen frequently in gunshot cases. With high-velocity spatter, the size of preponderant stain is 1 mm or smaller, as opposed to low-velocity spatter, which involves stains greater than or equal to 4 mm in diameter. In this case the pinkish hue came not from high-velocity but from the repetition of spatter in the same area.
This was perhaps the most fun and informative “final exam” I’ve ever taken – minus the clean up of course, which involved mopping floors and wiping down walls while the suspects went to the bathroom to wash the blood off their faces. Anyone seen the movie Sunshine Cleaning??? I will revisit Bloodstain Analysis again in the future since there’s so much to it and it’s just so damn cool. Now, how to apply this to animal cases? Same concepts, just different subjects, who bleed slower than humans and may have different spatter patterns as a result, plus they have lots of hair… hmm.. plenty of research for me.
And how did the actual case turn out? Well, the husband was convicted of aggravated assault (yes, ridiculous, I know, but apparently the court testimony involved a long story and cultural differences and the cooking consistency of rice… bunch of hooey, really). The knife wounds on his chest? Self-inflicted. A good lesson not only about blood but about the effectiveness of good counsel. | https://animalcsi.com/2010/12/ |
If I make the assumption that you’re in the position to buy a property – in other words, you have an income that can service a debt and you have a deposit to allow you to buy a property – then it comes down to this: the return you can get on your money.
Wanting to own your dream home is a personal factor that is up to you. I’m taking the sentimental value or the security value out of this question and thinking about it solely in investment terms. I’m talking purely about yield. I can’t answer the question in any other way.
Risk vs. reward
There’s a lot of data around what they call the Sharpe ratio. In finance, this index measures the performance of an investment compared to a risk-free asset.
Over a limited period time it can show whether the share market outperforms the property market in terms of yield or vice-versa. It depends on what the period of time is and when the end date of that period of time is.
Is buying a house a better investment in terms of yield than the share market?
When anyone wants to invest their spare capacity in income and their deposit, I think that real estate is a safer bet than other asset classes of investment. It’s more tangible, it’s more understandable and there’s a more ready market for it.
Therefore, I would only continue to rent and not invest my money in property if I was very confident that the other asset classes that I could invest my spare capacity in – my spare income in and my deposit in – would outperform real estate.
On balance, in my opinion, that’s a rare event and that property is always the best investment. Therefore, if I look at it purely as an investment, I would buy rather than rent.
Expectation vs. reality
“I can’t afford to buy in the area I’d like to live in but I want to get on the property market.”
If the question becomes: should I continue to rent until I can afford to buy where I want to live, that’s a different matter. My opinion on that is no, you shouldn’t, because where you can afford to live will probably outgrow your ability to save a deposit.
Buy where you can afford. Don’t try and save a deposit for a house in South Yarra in Melbourne or Paddington in Sydney if you’re on an average income because you’ll be saving forever. That needed deposit will increase at a faster rate than your savings will increase.
Buy in area where you can afford, not where you want to live. Picture: Gaye Gerard/NCA NewsWire
I would hedge my position, buy where I can afford to buy and rent where I want to live. Use your deposit for something you can afford to buy and just get into the property market.
What that does for you, is it allows the deposit you put into that property to keep up naturally with the property market increases. The return on a deposit at the moment, at a bank, is lucky to be 1 per cent per annum, whereas the property market is going to increase by a number north of that.
In Sydney, the average property increase has been 18.8 per cent in the past 12 months, you’re never going to get that on your deposit money anywhere. Never.
However, if you put that deposit into a property you can afford to buy – in the regions or a growing suburb – then that deposit, by definition, will keep pace.
More Coverage
Disclaimer: The information contained in this article is general in nature and does not take into account your personal objectives, financial situation or needs. Therefore, you should consider whether the information is appropriate to your circumstances before acting on it, and where appropriate, seek professional advice from a finance professional. | |
Introduction {#Sec1}
============
Several factors may predispose to or directly induce enamel damage during, or after, fixed orthodontic treatment. The post clean-up procedure after removal of attachments is regarded as the most significant cause of enamel damage \[[@CR1], [@CR2]\]. Therefore, various methods have been proposed for clean-up of residual orthodontic adhesives from the enamel surface, such as: hand instruments, stones (Arkansas stone, green stone), wheels and discs, scalers, dental burs (typically tungsten carbide burs), lasers and pumice or zirconium paste \[[@CR3]\]. Currently, no technique has proven capable of complete and efficient removal of residual adhesives, without inducing even a minor amount of enamel damage \[[@CR4]\]. These surface changes reduce the resistance of enamel to bacterial/organic acid attacks therefore increasing its susceptibility to demineralization and dental caries.
The critical threshold value of enamel surface roughness for bacterial adhesion has been established at 0.2 μm by Bollen et al. \[[@CR5]\]. A number of studies have shown that conventional methods of adhesive removal, including scalers and dental burs, may lead to visible surface roughness with gouges ranging from 10--20 μm deep, and loss of up to 100 μm thickness of enamel \[[@CR6]\]. Thus, maintaining the integrity of the enamel surface during the removal of residual adhesive is a key consideration during the removal of orthodontic appliances.
In recent years, air-abrasion has shown promise as a method for removing residual adhesives \[[@CR7]\]. Banerjee and his co-workers, in an in vitro air-abrasion study, reported that the bioactive glass powder 45S5 produced less enamel damage compared with alumina air-abrasion and tungsten carbide burs \[[@CR7]\]. However, there still remains a need to improve the properties of bioactive glasses to facilitate the safe removal of residual adhesives, with minimal/no enamel damage, following bracket debonding.
The aims of the present study were therefore:i.To develop a novel fluoride-containing bioactive glass with a hardness lower than that of the bioactive glass 45S5(Sylc™) and that of sound enamel surface, andii.To study the effectiveness of the novel glass in the removal of residual orthodontic adhesives from the enamel surface, when propelled via an air-abrasion hand-piece, in comparison with a TC bur and 45S5(Sylc™)-air-abrasion.
Material and methods {#Sec2}
====================
Glass design and synthesis {#Sec3}
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A series of three novel glasses incorporating SiO~2~− P~2~O~5~−CaO−Na~2~O−CaF~2~, based on the molar composition of a commercially-used bioactive glass 45S5(Sylc™; Denfotex Research Ltd., London, UK) were synthesized using a melt quench route (Table [1](#Tab1){ref-type="table"}). The Na~2~O content was systematically increased (in exchange for CaO) up to 30 mol%. High-phosphate content (6.1 mol% P~2~O~5~) was also used. In addition, a constant ratio of calcium fluoride (3 mol% CaF~2~) was added. The network connectivity value was kept constant (2.08) for all the experimental glasses. Each glass (batch size 200 g) was prepared by melting SiO~2~ (analytical grade; Prince Minerals Ltd., Stoke-on-Trent, UK), Na~2~O, CaO, P~2~O~5~, and CaF~2~ (Sigma-Aldrich, Gillingham, UK) in a platinum-rhodium crucible, in an electrical furnace (EHF 17/3, Lenton, UK) for 60 min between 1420 to 1450 °C (Table [1](#Tab1){ref-type="table"}). The resulting molten glass was rapidly quenched in deionized water (DW) to obtain glass frits, which were collected into a sieve and kept in a vacuum oven (Harvard LTE, UK) to dry at 80 °C overnight.Table 1Nominal glass composition (in Mol %) and melting temperature (Tm)GlassesMol %TmSiO~2~Na~2~OCaOP~2~O~5~CaF~2~45S5(Sylc™)46.124.426.92.61450QMAT1372033.96.131440QMAT2372528.96.131430QMAT3373023.96.131420
After drying, 100 g of each glass frit was ground using a vibratory mill (Gy-Ro mill, Glen Creston, London, UK) for 1 min to form glass powders, which were then sieved for 10 min (38 and 90 μm mesh analytical sieves; Endecotts, Ltd., London, UK), to obtain glass particle size fractions between 38 and 90 μm. Each glass powder was stored in dry re-sealable plastic bags until further use. Glass particles of \< 38 μm size were used for bioactivity tests to assess apatite formation (in Tris buffer solution), whereas glass particles between 38 and 90 μm were used for propulsion via the air-abrasion hand-piece. This range of particle size allowed escape of the glass powder through the hand-piece nozzle tip without agglomeration. Bioactive glass 45S5(Sylc™) was used as a reference with a particle size less than 38 μm for bioactivity tests and between 38 and 90 μm for air-abrasion studies.
Glass characterization {#Sec4}
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X-ray diffraction (XRD; X'Pert PRO MPD, PANalytical, Cambridge, UK; 40 kV/40 mA, Cu Kα, data collected at room temperature; results not shown) was used to determine the amorphous state of the glass. The glass transition temperature (Tg) was determined for each glass composition using Differential Scanning Calorimetry (DSC; Stanton Redcroft DSC1500, Rheometric Scientific, Epsom, UK). 50 mg (± 0.1 mg) of glass powder (\< 38 μm) was placed in a DSC platinum crucible and run against alumina powder (analytical grade) as a reference, at a heating rate 20 °C per minute in flowing nitrogen gas (flow rate of 60 ml/min), from 25 to 1000 °C.
Glass Vickers hardness measurements {#Sec5}
-----------------------------------
For hardness measurements, a glass rod (20 mm in diameter) was prepared from each glass batch, by re-melting approximately 100 g of glass frit, pouring into a graphite mould, and annealed for 1 h in a preheated furnace, at the Tg determined in 2.2. Thereafter, the casting glass was slowly cooled to room temperature overnight in the furnace, which was switched off. The rod from each glass batch was sectioned into approximately 1-mm thick discs using a diamond cutter machine (Accutom-5, Struers A/S, Ballerup, Denmark). These discs were subsequently polished with silicon carbide paper (P1000 in roughness) wet with acetone (instead of water), to avoid the glass reacting with water during polishing. The hardness of the discs was measured using a Vickers diamond pyramid indenter (Zwick/Roell, ZHU 187.5) with an applied load of 29.4 N for 10 s. The Vickers hardness number (VHN) of each glass composition was taken 10 times. The VHN values (displayed on the LCD) were averaged and presented as mean ± standard deviation (SD). QMAT3 experimental glass was selected for air-abrasion tests on the basis of its lower hardness compared to that of enamel and bioactive glass 45S5(Sylc™).
Glass particle size and shape {#Sec6}
-----------------------------
Particle size analysis was performed on glass powders using a Malvern/E Mastersizer (Malvern instruments, UK), since air-abrasion technique utilizes kinetic energy, which depends on the mass (size) and the velocity of the propelled glass powder particles. Approximately 30 mg of the glass powder was dispersed in DW until the ideal laser absorbance level was achieved. Two measurements were recorded and the average of these measurements was taken to produce a more reliable value. For glass particle shape, a scanning electron microscope (SEM-FEI Inspect F, Oxford instruments, UK) with an accelerating voltage of 20 kV and a working distance of 10 mm was used after mounting the glass particles on stubs, and sputter-coated with gold using an automatic sputter coater (SC7620, Quorum Technologies, UK).
Apatite formation in Tris buffer {#Sec7}
--------------------------------
Tris buffer solution was prepared (15.09 g Tris (hydroxylmethyl) aminomethane powder, 800 ml of DW and 44.2 ml of 1 M hydrochloric acid---Sigma Aldrich), and shaken (orbital shaker; IKA® KS 4000i control, Germany) at 37 °C overnight. The pH of the solution was measured using a pH meter (Oakton Instruments), and adjusted to \~ 7.25--7.4 (with 1 M hydrochloric acid); the volume of Tris buffer solution was increased to 2 litres by adding DW and stored in an incubator at 37 °C. In order to observe apatite formation of each glass powder, the latter was dispersed (75 mg; with a particle size \< 38 μm) into 50 ml of Tris buffer solution in a polyethylene bottle (150 ml). These bottles were then kept in a shaking incubator at 37 °C, with a rotation rate of 60 rpm, for the following time intervals: 1, 3, 6, 9, and 24 h.
After the designated time intervals, the glass powders immersed in Tris buffer solution were filtered (through filter paper; Fisher brand® qualitative filter paper). The glass powder within the filter paper was then placed in an oven at 37 °C for 24 h to be dried. The dried powders were subsequently analysed using Fourier transform infrared spectroscopy (FTIR; \~ 5 mg of each glass powder; \< 38 μm) and X-ray diffraction (XRD; 1 to 20 mg of each glass powder, with a particle size \< 38 μm). The FTIR (Spectrum GX, Perkin-Elmer, Waltham, USA) data was collected between from 500 to 1800 cm^−1^ ~,~ absorbance mode. The XRD (X'Pert PRO MPD, PANalytical, Cambridge, UK; 40 kV/40 mA, Cu Kα) data was collected at room temperature in the 2*θ* range of 10° to 70°.
Tooth sample preparation {#Sec8}
------------------------
Sixty human premolars, extracted for orthodontic purposes, were used (with approval from Queen Mary Research Ethics Committee QMREC 2011/99). These teeth were selected on the basis of visual observation using an optical stereo-microscope at ×4.5 magnification (VWR International Microscope). The inclusion criteria were no carious lesions, cracks or any other defects on the buccal surfaces. The selected teeth were cleaned and stored in DW in a refrigerator at 4 °C until required. Prior to the start of the experiment, these teeth were washed with DW, air-dried and embedded into plastic moulds filled with cold cure acrylic resin (Orthocryl™, UK), leaving the buccal surfaces exposed. The buccal surface of each tooth sample was polished with non-fluoridated pumice paste (20 s), rinsed with water and air-dried. Thereafter, a polyvinyl chloride tape was placed on the buccal surface of each tooth sample, excluding a 4 × 4 mm window at the centre for bonding of orthodontic brackets to the exposed enamel. The covered area was used as a reference for later visual comparison between the treated and untreated surfaces. Finally, these prepared teeth samples were stored in an incubator at 37 °C until the brackets were bonded.
Orthodontic adhesive removal {#Sec9}
----------------------------
Following the manufacturer's instructions, two light-cured orthodontic adhesive systems: resin composite; Transbond XT™ (3 M Unitek, Monrovia, CA, USA), and resin modified glass ionomer cement; Fuji Ortho LC™ (GC corporation, Tokyo, Japan) were used to bond 60 premolar metal brackets (MiniSprint®, Forestadent, Pforzheim, Germany) to the prepared teeth samples (30 premolar teeth per each orthodontic adhesive system group). Enamel etching with 37% phosphoric acid was undertaken for 30 s prior to application of Transbond XT™. When the brackets were placed, each bracket was subjected to a 300 g compressive force using a force gauge (Correx Co, Berne, Switzerland) for 5 s, to ensure a uniform thickness of the adhesive \[[@CR8]\]. After bonding, the teeth with the attached brackets were stored in DW for 1 week at 37 °C. Thereafter, the plastic moulds (with the extracted teeth mounted) were held by a special holding device (Instron® machine, UK), to remove the attached brackets from the buccal surfaces using a debonding plier (Ixion™, DB Orthodontics) by one operator. Three different clean-up methods (slow-speed tungsten carbide bur (TC), 45S5(Sylc™)-air-abrasion, and the selected experimental glass (QMAT3)-air-abrasion were used for removal of the residual of the aforementioned two orthodontic adhesive systems following bracket debonding. The teeth samples of each orthodontic adhesive system group were randomly assigned to three groups (ten teeth for each post clean-up method). Both the commercially available bioactive glass 45S5(Sylc™) and QMAT3 glass were propelled via an air-abrasion hand-piece (BA Ultimate air polisher) connected to a dental chair unit. The operating parameters were air-pressure 60 psi, nozzle angle 75° and nozzle tip-enamel surface distance of 5 mm. Complete removal of the adhesive remnants was assessed by visual inspection under a dental operating light and later verified by an optical stereo-microscope at ×4.5 magnification (VWR International Microscope). A non-contact white light profilometery (Proscan®2000, Scantron, Taunton, UK) was used to measure the enamel surface roughness for all prepared teeth samples before bracket bonding, after post clean-up method, and after polishing (using rubber cup and non-fluoridated pumice for 20 s). In addition, scanning electron microscopy (SEM-FEI Inspect F, Oxford instruments, UK) was used to examine the enamel surface damage following the aforementioned post clean-up methods, and the time required to remove adhesive remnants was also assessed.
Statistical analysis {#Sec10}
--------------------
Statistical analysis was performed with the SPSS software package (version 24; SPSS Inc., New York, NY, USA). Two-way analysis of variance (ANOVA) and Tukey's HSD post-hoc test were used to test significant differences in enamel surface roughness under three different conditions (before bracket bonding, after post clean-up methods following bracket debonding, and after polishing). The level of significance was pre-specified at alpha = 0.05.
Results {#Sec11}
=======
Glass characterization and Vickers hardness measurements {#Sec12}
--------------------------------------------------------
The glass transition temperature (Tg) of both 45S5(Sylc™) and experimental glasses are shown in Table [2](#Tab2){ref-type="table"}. The Tg was 530 °C for 45S5(Sylc™) with sodium and phosphate contents of 24.4 and 2.6 mol%, respectively. The Tg of QMAT3 reduced to 355 °C as the sodium and phosphate increased to 30 and 6.1 mol%, respectively. This was also associated with the addition of a constant ratio of fluoride (3 mol%). Furthermore, the Vickers hardness number (VHN) decreased dramatically (Table [2](#Tab2){ref-type="table"}) from 472.8 ± 2.28VHN (\~ 4.63GPa) for 45S5(Sylc™) to 350.4 ± 1.14VHN (\~ 3.43GPa) for QMAT3. The experimentally determined VHN were converted to GPa units using the equation: GPa = VHN × 0.009807.Table 2Glass transition temperature (Tg), and Vickers hardness number (VHN) of 45S5(Sylc™) and experimental glassesBioactive glassesTg (°C)Vickers hardness (VHN) mean ± SDHardness (GPa)45S5(Sylc™)530472.8 ± 2.284.63QMAT1524458.6 ± 2.504.49QMAT2450433.6 ± 1.944.25QMAT3355350.4 ± 1.143.43
Glass particle size and shape {#Sec13}
-----------------------------
The particle size distribution (in micrometres; μm) of 45S5(Sylc™) glass and experimental glasses are given in Table [3](#Tab3){ref-type="table"}, where D10 represents 10% of the glass particle size, indicating the fine particles within the distribution D50 represents 50% of the glass particle size, giving a measure of the mean particle size within the distribution and D 90 represents 90% of the glass particle size, reflecting larger particle sizes.Table 3Particle size distribution of 45S5(Sylc™) and experimental glassesBioactive glassesParticle size (μm)D10D50D9045S5(Sylc™)34.163.576.8QMAT138.665.577.2QMAT238.965.577.2QMAT333.862.776.7
SEM images of 45S5(Sylc™) and experimental glasses are presented in Fig.[1](#Fig1){ref-type="fig"}. All glasses show similar morphology, represented as sharp, angular irregular particles of variable sizes (in micrometres).Fig. 1SEM images of (**a**) 45S5(Sylc™), (**b**) QMAT1, (**c**) QMAT2, and (**d**) QMAT3 at ×250 magnification
Apatite formation in Tris buffer {#Sec14}
--------------------------------
After immersion in Tris buffer solution for 1, 3, 6, 9 and 24 h, the FTIR spectra for all experimental glasses showed dramatic changes compared to their respective untreated (not immersed) versions. The latter were characterized by the presence of two main bands at 910 and 1040 cm^−1^, indicating non-bridging oxygen (Si^+^-O^-^- M^+^, where M^+^ is an alkali metal modifier element) and vibrational stretching of Si-O-Si, respectively \[[@CR9], [@CR10]\]. After immersion, the non-bridging oxygen (Si^+^-O-M^+^) band at 910 cm^−1^ disappeared, and a single P--O vibration band at 560 cm^−1^ appeared after 3 h, which is an indicator for the presence of apatite precursors \[[@CR9]\]. At 6 h, the latter band split into prominent twin bands at 560 and 600 cm^−1^, which became well-defined with longer immersion times. These twin bands indicate the presence of apatitic PO~4~ ^3−^groups, the main characteristic feature of apatite, including hydroxyapatite, fluorapatite and carbonated hydroxyapatite \[[@CR11], [@CR12]\]. The formation of apatite was confirmed by the presence of a sharp phosphate band (PO~4~)^3−^ at 1040 cm^−1^ after 6, 9 and 24 h of immersion \[[@CR9]\]. Conversely, 45S5(Sylc™) did not show any bands at 560 and 600 cm^−1^, with the absence of the sharp phosphate band at 1040 cm^−1^ at 6 h. Apatite formation features of 45S5(Sylc™) appeared at 24 h but these were still less prominent compared to those obtained for all experimental glasses (Fig.[2](#Fig2){ref-type="fig"}).Fig. 2FTIR spectra for (**a**) QMAT1, (**b**) QMAT2, (**c**) QMAT3 and (**d**) 45S5(Sylc™) after immersion in Tris buffer solution
With regard to XRD patterns, all the experimental glasses showed a small peak at 26° and a broad peak from 32° to 34° 2*θ* after 6 h of immersion in Tris buffer solution, superimposing the amorphous broad peak of untreated glass and those that were immersed for 1 and 3 h (Fig.[3](#Fig3){ref-type="fig"}). These two peaks, indicating the presence of apatite, became more pronounced as the immersion time increased. However, all these peaks were absent in 45S5(Sylc™) until 24 h, when much smaller peaks indicative of apatite appeared \[[@CR13]\].Fig. 3XRD data for (**a**) QMAT1, (**b**) QMAT2, (**c**) QMAT3 and (**d**) 45S5(Sylc™) after immersion in Tris buffer solution
Orthodontic adhesive removal {#Sec15}
----------------------------
The profilometry analysis was carried out on three experimental groups (TC group, 45S5(Sylc™)-air-abrasion, and QMAT3-air-abrasion) for each orthodontic adhesive. The means and standard errors (SE) of the average enamel surface roughness (Ra) in micrometers, under three different conditions, are presented in Table [4](#Tab4){ref-type="table"}. No statistically significant differences were observed in the enamel roughness measurements among the six experimental study groups before bracket bonding (baseline measurements). For Transbond XT™ resin groups, the enamel roughness significantly increased after post clean-up with TC bur (2.93 ± 0.06 μm), and 45S5(Sylc™) (1.89 ± 0.04 μm) compared with their corresponding baseline measurements (*p* \< 0.001), while QMAT3-air-abrasion group did not exhibit any significant difference in enamel roughness (*p* = 0.927). In addition, enamel roughness values after polishing were significantly higher for both the TC and 45S5(Sylc™)-air-abrasion groups (2.73 ± 0.77 μm and 1.81 ± 0.05 μm, respectively), than their corresponding baseline measurements (*p* \< 0.001). However, no significant difference was shown following clean-up with QMAT3-air-abrasion and subsequent polishing and baseline values (*p* = 0.983). Furthermore, enamel roughness measurements did not appear to be affected by polishing subsequent to clean-up in each group (*p* = 0.104 to 1.000) compared to those after clean-up.Table 4Enamel surface roughness (Ra) in micrometers (mean ± SE) for each experimental group under three different conditionsGroup (*n* = 10)Experimental group based on:\
orthodontic adhesive + post clean-up method usedBefore bracket bonding (baseline)After post clean-up methodAfter polishing1Transbond XT™ + TC0.49 ± 0.272.93 ± 0.062.73 ± 0.772Transbond XTT^M^ + 45S5(Sylc™)-air-abrasion0.51 ± 0.031.89 ± 0.041.81 ± 0.053Transbond XT™ + QMAT3-air-abrasion0.49 ± 0.040.58 ± 0.020.56 ± 0.034Fuji Ortho LC™ + TC0.54 ± 0.022.57 ± 0.052.63 ± 0.065Fuji Ortho LC™ + 45S5(Sylc™)-air-abrasion0.46 ± 0.041.59 ± 0.021.74 ± 0.046Fuji Ortho LC™ + QMAT3-air-abrasion0.36 ± 0.020.51 ± 0.040.45 ± 0.01
With Fuji Ortho™ resin modified glass ionomer cement, similar patterns were observed for enamel roughness measurements. They were significantly higher after post clean-up in the TC (2.57 ± 0.05 μm) and 45S5(Sylc™)-air-abrasion groups (1.59 ± 0.02 μm) compared to baseline measurements (*p* \< 0.001), but the QMAT3-air-abrasion group (0.51 ± 0.04 μm) did not show any significant difference with their corresponding baseline measurements. In addition, significantly higher enamel roughness values were shown in TC and 45S5(Sylc™)-air-abrasion groups (2.63 ± 0.06 μm and 1.74 ± 0.04 μm, respectively) after polishing than their corresponding baseline measurements (*p* \< 0.001), but no significant difference was shown between those of QMAT-air-abrasion and their corresponding baseline measurements (*p* = 1.000).
The time required to remove the orthodontic adhesives was recorded for three post clean-up methods: TC bur, Sylc™-air-abrasion, and QMAT3-air-abrasion ([Table]{.ul} [5](#Tab5){ref-type="table"}). Differences between QMAT3 glass (42.51 ± 1.11 s) and Sylc™ (40.72 ± 0.92 s) were not statistically significant (*p* = 0.913) in the Transbond XT™ groups. However, both took longer (*p* \< 0.001) to remove excess Transbond XT™ resin compared to the TC bur (23.2 ± 1.58 s). A similar pattern was observed in the Fuji Ortho LC™ groups with no significant differences (*p* = 0.893) found between the time required to remove Fuji Ortho LC™ by both QMAT3 and Sylc™ glasses, while both glasses took significantly longer than the TC bur (*p* \< 0.001).Table 5Means ± SE of the time (seconds) required to remove two residual orthodontic adhesives after bracket debondingGroup (*n* = 10)Experimental study group based on:\
orthodontic adhesive + post clean-up method usedTime (Sec.)1Transbond XT™ + TC23.20 ± 4.992Transbond XT™ + 45S5(Sylc™)-air-abrasion40.71 ± 2.893Transbond XT™ + QMAT3-air-abrasion42.51 ± 3.514Fuji Ortho LC™ + TC22.90 ± 4.415Fuji Ortho LC™ + 45S5(Sylc™)-air-abrasion38.42 ± 4.296Fuji Ortho LC™ + QMAT3-air-abrasion40.32 ± 3.36
Representative SEM images (at ×250 magnification) are shown in Fig.[4](#Fig4){ref-type="fig"} prior to bracket bonding and after the three post clean-up methods (TC bur, 45S5(Sylc™)-air-abrasion, and QMAT3-air-abrasion). The sound enamel surface appeared smooth before bracket bonding (Fig.[4](#Fig4){ref-type="fig"}a), whilst it became roughened and pitted surface after the use of a slow-speed TC bur (Fig.[4](#Fig4){ref-type="fig"}b). In addition, the enamel surface, following 45S5(Sylc™)-air-abrasion is seen to have microscopic roughness in some areas (Fig.[4](#Fig4){ref-type="fig"}c), while a uniformly smooth surface was obtained after using QMAT3-air-abrasion (Fig.[4](#Fig4){ref-type="fig"}d).Fig. 4Representative SEM images (×250 magnification) of the enamel surface. (**a**) Before bracket bonding. (**b**) After clean-up using the TC bur. (**c**) After clean-up using 45S5(Sylc™)-air-abrasion. (**d**) After clean-up using QMAT3-air-abrasion
Discussion {#Sec16}
==========
Glass characteristics {#Sec17}
---------------------
Bioactive glass, 45S5, has been used in a number of commercial products such as NovaBone™ (orthopaedic application), Perioglass™ (periodontal application), Sylc™ and NovaMin™ (dental application) \[[@CR14]\]. Furthermore, preliminary in vitro research has been undertaken on its use via propulsion using air-abrasion, in order to cut sound and carious enamel and dentine \[[@CR15], [@CR16]\], remove residual orthodontic adhesive following bracket debonding from enamel surfaces \[[@CR7]\] and potentially re-mineralize white spot lesions \[[@CR17]\]. However, this glass has higher hardness than that of sound enamel (\~ 3.5GPa) \[[@CR18]\] with reported values varying between 4.5GPa \[[@CR19]\] and 5.75GPa \[[@CR20]\], thus risking roughening of the enamel surface. Therefore, it is desirable to develop glasses which have similar or lower hardness than that of enamel.
It has been reported that increasing Na~2~O content (in exchange for CaO), across a series of bioactive glasses, with a constant network connectivity value close to two, resulted in a linear decrease in Tg and density of the glass \[[@CR21], [@CR22]\]. This was attributed to the substitution of CaO for Na~2~O producing a more disrupted silicate glass network, since one Ca^2+^ was replaced by two Na^+^ ions. This resulted in the loss of the ionic bridges that Ca^2+^ ions provided between two adjacent non-bridging oxygens, contributing to a decrease in the packing density of the glass. Therefore, less rigid glasses were formed with a lower glass transition temperature (Tg) to transform them from a molten liquid to a glassy state.
Additionally, it has also been reported that a reduction in silica content, characteristic of all experimental glasses tested compared to the proprietary bioactive glass 45S5(Sylc™), resulted in a decrease in Tg \[[@CR23]\]. In the latter study, a reduction in silica content was accompanied by an increase in phosphate content. Similarly, a range of studies \[[@CR13], [@CR14], [@CR24]\] have reported a decrease in Tg related to a reduction in silica content accompanied by an increase in phosphate content and the addition of fluoride. Moreover, the addition of fluoride to bioactive glasses has also been reported to lower the Tg as well as to promote fluorapatite formation, which is more stable and resistant to acid attack, compared with hydroxyapatite \[[@CR25], [@CR26]\].
Fluoride, in the form of CaF~2~, was incorporated in the composition of all experimental glasses in this study. The amount of CaF~2~ was kept constant (3 mol%) to enhance fluorapatite formation and prevent fluorite development (as a result of excessive fluoride; ≥ 5 mol%) \[[@CR13], [@CR26], [@CR27]\]. The formation of fluorite indicates crystallization of the glass, resulting in inhibition of its bioactive properties; the presence of crystalline phases gives rise to increased resistance to ion exchange reactions between the glass surface and physiological solution, which in turn affect apatite formation. Furthermore, the phosphate content in this study was also increased from 2.6 mol% in the reference glass 45S5(Sylc™) to 6.1 mol% in all experimental glasses. This formulation was informed by two recent studies \[[@CR13], [@CR28]\] indicating that increasing the phosphate content to approximately 6 mol% in fluoride-containing glasses resulted in an increase in the degradation of the glass, leading to a rapid release of calcium (Ca^2+^) and orthophosphate (PO4^3−^) ions to the surrounding solution, thus forming fluorapatite within 6 h after immersion in Tris buffer solution. The results of this study regarding apatite formation are consistent with these findings.
Interestingly, it was also evident that increasing the Na~2~O content in the present study, resulted in a decrease in hardness values for all experimental glasses to (3.43GPa for QMAT3) compared with the reference 45S5(Sylc™; 4.63 GP). Hence, QMAT3 conserved the enamel surface while removing the residual adhesives, without inducing undesirable surface enamel changes. It should be noted that the available information on the hardness values of bioactive glasses is limited due to the relatively small number of studies investigating this property. Reported values vary significantly from one study to another; for example, the hardness for bioactive glass, 45S5 reported by Lopez-Esteban et al. \[[@CR20]\] and Farooq et al. \[[@CR28]\] were 5.75GPa and 5.84GPa, respectively. This variation might be due to the differences in the methodology used to prepare these glasses, and the indenter load used to measure the hardness, although all studies used a Vickers's instrument. Moreover, in the current study the indenter load was 2.9 kg while the indenter loads used by Lopez-Esteban et al. \[[@CR20]\] and Farooq et al. \[[@CR28]\] were 0.5--1.2 and 0.01 kg, respectively.
Ninety per cent of each experimental glass (QMAT1, QMAT2 and QMAT3) had a particle size of 77.2, 77.2 and 76.7 μm, respectively. These values were close to those for 45S5(Sylc™; 76.8 μm). The larger mass (particle size) leads to higher kinetic energy since the latter relates to the mass (particle size) and velocity. In addition, the presence of large particles and the absence of fine particles prevented agglomeration of the glass powder, since fine particles can result in clumping and stagnation of the glass powder within the nozzle tip of the air-abrasion hand-pieces, thus potentially hindering the air-abrasion process.
With regard to the morphology of the commercially-available 45S5(Sylc™) glass and experimental glasses, the SEM images revealed a very similar appearance characterized by sharp, angular and irregular particles, thus aiding in removing the residual of orthodontic adhesives.
The FTIR spectra and XRD patterns of 45S5(Sylc™) and all experimental glasses showed dramatic changes after immersion in Tris buffer solution for periods of 1, 3, 6, 9 and 24 h. These changes related to ion exchange between the glass powder and the Tris buffer solution forming a silica-gel surface layer-Si(OH)~4~ on the glass surface after breaking of the Si-O-Si bonds. This was followed by leaching of calcium, phosphate and fluoride from the glass into the solution to form apatite. These findings were in agreement with the mechanism of apatite formation proposed by Hench \[[@CR29], [@CR30]\]. Furthermore, the ability of experimental glasses to form apatite in 6 h, compared with 24 h for the commercially-available 45S5(Sylc™), after immersion in Tris buffer solution, were consistent with previous findings of Farooq et al. \[[@CR28]\] and Mneimne et al. \[[@CR13]\].
Orthodontic adhesive removal {#Sec18}
----------------------------
It has previously been reported that TC bur increased enamel roughness compared to composite burs \[[@CR31]\], white stone \[[@CR32]\], stainburster bur \[[@CR33]\] and adhesive residue remover \[[@CR34]\]. These studies compared results with atomic force microscopy, profilometry and 3D scanning in blue-light technology. In the present study, the profilometry data revealed that the use of the TC bur in removing residual orthodontic adhesive increased enamel surface roughness regardless of the type of adhesive used. 45S5(Sylc™)-air-abrasion also produced an increase in the enamel roughness to some extent. These findings are in agreement with Banerjee et al. \[[@CR7]\], who demonstrated that removal of residual adhesive resin (Unite™) using alumina air-abrasion caused more enamel loss (0.0386 mm^3^), followed by the TC bur (0.285 mm^3^) and finally 45S5 air-abrasion (0.135 mm^3^). In the present study, the novel experimental glass (QMAT3) induced less enamel roughness compared with the TC bur and 45S5(Sylc™)-air-abrasion, irrespective of the adhesive material used, a finding which was corroborated using SEM imaging. This finding relates to the lower hardness value of QMAT3 which approximates but does not exceed that of the enamel surface. Therefore, propelling this glass powder was less likely to roughen the enamel surface, mitigating the associated risk of plaque accumulation and caries formation. Furthermore, the handling technique used in this study was similar to that used by Paolinelis et al. \[[@CR16]\], who confirmed that using the aforementioned operating parameters increased the cutting efficiency of the air-abrasion technique. Consequently, using accepted clinical handling parameters it appears that this novel glass powder may be capable of selective removal of orthodontic adhesives without inducing deleterious abrasion of the enamel surface, although quantification of the volume of loss was not undertaken.
Further laboratory research in relation to the cutting efficiency of this approach is required prior to clinical application, although preliminary data suggests comparable levels of efficiency to other bioactive glass formulations. Adhesive removal took approximately half the time with the TC bur. This discrepancy might relate to the aggressive cutting associated with sharp cutting blades of TC bur while bioactive glass propulsion works by means of abrasion. Similar conclusions were reached by both Karan et al. \[[@CR31]\] and Mohebi et al. \[[@CR32]\], who reported that TC burs removed adhesive remnants faster than composite bur and white stone, respectively. Moreover, polishing with non-fluoridated pumice for 20 s has little effect on enamel surface roughness values. These findings mirror analogous studies involving use of non-fluoridated pumice for 10 to 30 s \[[@CR35]--[@CR37]\] suggesting that polishing does not affect either the grooves or pits induced by enamel clean-up methods.
The ability of QMAT3 glass to form apatite earlier than 45S5(Sylc™) offers further promise to induce enamel remineralization; this potential may lead to application in the management of both pit and fissure, and smooth surface enamel caries. Notwithstanding this, it is important to emphasize that the present research is limited by its ex vivo nature; as such, replication within an in vivo situation is required. Moreover, blinding of the investigator was not performed, risking the introduction of assessor bias. In addition, teeth were stored in deionized water rather than undergoing a simulated artificial aging process involving thermomechanical cycling, the latter approach may have been more clinically representative, although use of water storage remains an accepted approach \[[@CR38]\]. However, in view of the promising physical and handling properties highlighted in the present study, the remineralization potential of QMAT3 for orthodontically-induced white spot lesions will be explored in ongoing laboratory research.
Conclusions {#Sec19}
===========
A novel bioactive glass (QMAT3) with a lower hardness than 45S5(Sylc™) and enamel has been developed. Its bioactivity was proved by early apatite formation compared with a proprietary agent. QMAT3 was capable of selective removal of residual orthodontic adhesive without inducing enamel damage. It, therefore, shows promise as a viable alternative to adhesive removal with a TC bur.
This study is a part of a PhD that is being funded by the Iraqi Ministry of Higher Education and Scientific Research.
Conflicts of interest {#FPar1}
=====================
One of the four authors is an inventor on the patented bioactive glass: WO 2011/161422.
Ethical approval {#FPar2}
================
This article does not contain any studies with human participants or animals performed by any of the authors.
Informed consent {#FPar3}
================
For this type of study, formal consent is not required.
| |
Illustrated by Scott Gandell
There wasn’t supposed to be water here. They brought it with them. They swallowed up the Earth with it and let it seep into the ground, men shoveling and heaving to make a hole, a massive bathtub to fill with water and call a lake. The water was clear then, not murky like it got to be, clear and lined with lotuses, fragrant and full, white saucers with yellow yolks. They are gone now. The water, drained. A mound of gravel rests in the middle of the lake, waiting to make a parking lot.
The statue of The Lady of the Lake still stands, tall and proud, on the tip of the peninsula overlooking the cracked dirt. Her mouth is tightly closed, as if she is holding in a secret. Her eyes are hollowed and emptied by the broken promises of others. Yellowed photographs of deceased women and children litter the cement block she stands on, smiling faces perched against candles of La Virgen de Guadalupe and wilted marigolds.
She is stuck here, just like me, stuck to this Earth. This woman encased in stone. I hunch over her feet and touch the folds on the bottom of her gown. It feels cool beneath my palms. My fingers claw at the tips of her toes; the mud from my hand smears the white stone black as I kiss her feet. My fingers poke through the holes of my dress—the tears and snags caused by fallen tree branches and shrubs, the ones that used to line the lake before they were uprooted—as I wipe the dirt away from her toes.
Before the lake was closed off, they came for her, Angelenos bearing gifts and prayers.Abuelitas with their roses and spicy mango slices, pimply-faced teenagers looking for a place to spoon, models in polka-dot bikinis and evening gowns contorting their bodies for the camera, men on their lunch breaks drinking forties, families celebrating birthdays, quinceañeras, anniversaries, and deaths.
At night, boys who wanted to be men would touch her. They came to leave their mark on her, to try and claim her as their own; ExP is sprayed across her breasts, AHTS across her hips, and LA on her back in red. The boys were covered in signs too, cryptic layers of ink that covered their faces, chests, and arms—messages of love and hate that peaked out from beneath their shirts. When they thought no one was watching, they cried at her feet and pleaded for her to pray for them, to help them.
Even now, the fence doesn’t stop them. They cut holes in the bottom of the chain-link and swiftly squeeze themselves through it or, if they’re strong enough, climb over. Their movements send ripples through the metal and, when they reach the top and jump, their momentarily airborne bodies appear weightless.
Like those boys, I beg for her help, for her forgiveness. I beg her to undo the curse placed upon me. I get down on my knees and weep. I repeat the names of my children under my breath over and over. The children I have lost because of my own selfishness. I tell her to punish me for what I have done, to fill the lake with water again and send me to the bottom of it with them, to send me someplace, anyplace but here. Please, I say, anything but this silent waiting. I clasp my hands tighter together and burrow my nails into my skin, hoping to break the flesh. I feel nothing. I collapse at her feet, waiting for guidance, waiting for a sign.
* * *
When they came in their trucks, men shouting with their helmets and drills, I watched as they slowly drained the lake, as they destroyed what they had made and nature had gotten used to.
At first, I thought they had come to rescue me, to save me from the land I was tied to. Men with purpose, I thought, men who could move mountains and lakes if they wanted to.
“Are these the children who will save me?” I asked The Lady.
She stood over me. Be patient, her eyes seemed to say.
I tried. I sat and watched the workers as they came and went. Their neon vests moved like clusters of ants as they stomped through bougainvillea bushes and tore up patches of grass, clearing the perimeter to make space for their fence. I saw the greed in their eyes as they did it, as they put their metal posts into the ground and glued them to the Earth with concrete, closing off the lake to everyone but themselves, trapping The Lady and me inside of our home.
They brought long hoses that moved across the lake’s surface like hungry snakes. They gulped down the water and pumped it into the tanks that waited on Glendale Boulevard, gallons of water that were packed up and driven down the 5, out the 710, and into the Pacific.
“Are these the children who will save me?” I asked The Lady again. “Will these men destroy my secret, my shame, and I will be set free?”
As they drained the lake, I closed my eyes and remembered them. The faces of my children as they floated in the water, their mouths open as they cried out my name, as they cried for help, begging for mercy. Their limp bodies on the water’s surface, their hollow eyes staring up at the sky. I saw the pale little faces and the round cheeks. She has your eyes, people used to say. He has his nose. They haunt me. Those empty eyes pleading for help.
I open my eyes and look out upon the dry muck. The secrets the lake has kept hidden, wrapped tightly in her soil, lay naked upon the ground, basking beneath the sun. But my secret, my shame, remains hidden deep inside me. | https://locavorelitla.org/journal/issue-4/these-are-my-children/ |
Mycobacterium avium subsp. paratuberculosis (MAP) is one of the most fastidious members of the Mycobacterium genus. It is the causal agent of Johne's disease (also known as paratuberculosis) which is an untreatable disease characterized by granulomatous enteritis, diarrhoea, loss of body weight and death (Chiodini 1993).
Although it is generally assumed that this infection occurs similarly in all domestic ruminant species, there is sufficient evidence to suggest that MAP infection in small ruminants is different to that in cattle, both in the clinical form as well as the MAP strains involved (Clarke 1997).
The disease is responsible for significant economic losses to livestock production worldwide (Sweeney 2011, Garcia and Shalloo 2015). Additionally, a zoonotic potential has been proposed since MAP has been consistently found in humans with Crohn's disease (Zarei-Kordshouli et al 2019). Furthermore, an increasing number of diseases such as Blau syndrome, type 1 diabetes, Hashimoto thyroiditis and multiple sclerosis have also been associated to MAP presence, reinforcing the zoonotic potential of this pathogen (Lee et al 2011, Sechi and Dow 2015).
Some research on MAP infection in Colombia has been reported for small ruminants (Mogollón et al 1983, Mancipe et al 2009, Hernández et al 2017), but information on the presence and distribution of this infection is still scarce and the true prevalence (TP) of MAP infection in sheep populations in Colombia is clearly unknown. However, the Colombian sheep industry has identified paratuberculosis as one of the causes of the low development of the industry, limiting meat commercialization at national and international levels (Castellanos et al 2010). Unfortunately, there are currently no programs regarding the prevention and control of MAP infection for sheep populations in Colombia.
The lack of a prevalence estimate not only limits the capacity to assess the real impact of this important infectious disease, but also limits the capacity to allocate sufficient resources for its control precluding an adequate monitoring of the effectiveness of potential control measures. Since neither the Colombian sheep industry nor the Colombian government have estimates on the TP of MAP infected flocks, we aimed to accurately estimate the flock level prevalence of MAP infection and also to explore flock level risk factor associated with the presence of MAP antibodies in these sheep flocks located in the Antioquia province, Colombia.
MATERIAL AND METHODS
STATEMENT OF ANIMAL RIGHTS
The authors declare that the present study does not contain clinical studies or patient data. Informed consent was obtained from all individual participants included in the study. The study was conducted according to the current law of animal protection in Colombia and was approved by the Ethics Committee for Animal Experimentation of the Universidad de Antioquia, Colombia (Act 111, May 2017).
ANIMAL POPULATION AND STUDY DESIGN
A cross sectional study was carried out using ELISA test as well as faecal culture and direct qPCR as diagnostic tools to assess MAP infection prevalence in this animal population and to explore the influence of multiple flock management practices associated with MAP seroprevalence (figure 1).
To avoid a possible selection bias and taking into account that in the province of Antioquia there were no official records of sheep flocks, a census to identify each sheep farm located in the study region was carried out before selecting the participants. According to this, the whole sheep population located in the Metropolitan Area, the Northern, and the Eastern region of the Province of Antioquia, Colombia, were the sample frame of the present study (n=2,479).
As a result of this search, 25 sheep farms were identified but one refused to participate in the study. All remaining sheep farmers agreed to participate, permitting the sampling and the interview (n=24) to take place. The Metropolitan Area region, the Northern region, and the Eastern region of the Province of Antioquia, Colombia were selected as the study regions due to their increase in sheep production in recent years and proximity to Medellín city, which is the nearest and main sheep consumption market.
The only inclusion criterion for sampling was that animals must be over one year of age. A representative sample of this animal population was taken following a multistage sampling procedure, in which a constant proportion of animals was taken from each flock (Dohoo et al 2010). The sample size calculation allowed an error of 5%, 95% confidence, and expected prevalence of 50%. According to this, the sample size was estimated at 384 animals. In each study participant flock, 20% of the animals over one year of age was randomly sampled. In those flocks with less than 20 animals over one year of age, only five animals were sampled in order to complete at least one single faecal pool. In total, 456 animals were sampled in selected flocks.
DATA AND SAMPLE COLLECTION
Between August and September 2017, each of the 24 sheep flocks was visited once for data and sample collection. Overall, blood and faecal samples were collected from 456 sheep of the 24 participating flocks. Available data regarding flock management practices were collected using a questionnaire, the same day in which blood and faecal samples were collected. The information was obtained from the flock manager or flock owner. All questionnaires included an introductory paragraph explaining the rationale and importance of the questions, how data was going to be used, and a confidentiality agreement. The questions were divided into three sections: 1) general information of the herd, 2) herd management practices, and 3) knowledge about the disease. Questions were read out to the farmer and answers were selected from multiple closed responses or otherwise written down. The questions searched for MAP infection transmission risk factors in ruminants, for example: shared roads between neighbouring flocks (Dhand 2007), presence of different species of ruminants in the same flock (Al-Majali et al 2008), co-grazing between cattle and goats or sheep (Cetinkaya et al 1997), community grazing, poor control of intestinal parasites (Angelidou et al 2014) and animal trade between related flocks (Marquetoux 2016).
DIAGNOSTIC TESTS
Enzyme-linked Immunosorbent Assay (ELISA). Blood samples were taken from the jugular vein using Vacuette® tubes of 7 mL without anticoagulant (Greiner Bio-one, Kremsmünster, Austria) and a single 21G x 1V2" needle per animal, after local cleaning and disinfection with antiseptic alcohol. After collection, the blood samples were left to stand at room temperature to allow clot retraction. Subsequently, each sample was centrifuged at 2000-2500 rpm for 3-5 minutes to ease the serum extraction. The serum obtained was kept refrigerated until arrival at the Diagnostic Unit of the Facultad de Ciencias Agrarias, Universidad de Antioquia in Medellin, Colombia, where it was frozen at -20 °C until analysis by ELISA in October 2017. The presence of antibodies against MAP in the blood serum samples was determined by ELISA using the commercial diagnostic kit CATTLETYPE® MAP Ab (Qiagen, Leipzig, Germany) according to manufacturer guidelines.
The test characteristics of the ELISA assays used in this study, which are licensed in Germany for the detection of antibodies against Mycobacterium avium subsp. paratuberculosis in cattle, are sensitivity 59.1% and specificity 98.6%, determined by the Friederich Loeffler Institut, National Reference Laboratory for Paratuberculosis, using the reference panels for serum and milk of the NRL for paratuberculosis.
Culture. From each of the 456 study animals, a faecal sample (2-5 g) was taken with a new clean glove directly from the rectum. No animals had been vaccinated against MAP infection and researchers were unaware of their historical infectious status or the status at the time of sampling. The samples were kept refrigerated until arrival at the laboratory. To overcome the high costs of faecal culture, faecal samples of individual animals were pooled at the laboratory. Therefore, individual faecal samples of five animals from the same flock were pooled in a new sterile container (Fiorentino et al 2012, Mita 2016). Briefly, each faecal sample (2-5 g) from the study animals was homogenised in a sterile container. The pools (n=90) were frozen at -80°C, then shipped to the Laboratorio de Enfermedades Infecciosas, Instituto de Medicina Preventiva Veterinaria, Universidad Austral de Chile, Valdivia, Chile at 4°C allowing the slow defrosting of samples. On arrival, samples were immediately refrigerated and processed by both culture and direct MAP qPCR detection within the following hours. Pool faecal samples were processed in the BACTEC™ MGIT™ Para TB System (BD Diagnostic Systems, Franklin, NJ, USA), according to the manufacturer's instructions. Each inoculated MGIT tube was inserted into an MGIT 960 instrument (BD Diagnostic Systems, Franklin, NJ, USA) and incubated at 37°C for 49 days. Tubes signalling positive by day 49 were removed and confirmed for the presence of MAP by IS900 qPCR. Tubes not signalling positive by that time were considered negative.
DNA extraction. A simple, efficient and low-cost method of harvesting MAP DNA based on mechanical cell disruption was used to extract DNA from direct faecal pool samples as well as from a positive MGIT culture tube (Salgado et al 2014). Briefly, a 200 pL aliquot of a bacterial suspension from pooled faecal samples or the medium of the MGIT tube was aseptically transferred to 1.5 mL centrifuge tubes, which were then centrifuged at 5,000 g for 5 min. The supernatant of each tube was discarded, and the opening of the tube was briefly touched with a clean soft paper tissue to remove the remaining liquid. The pellet was disrupted by pipetting with a mixture of 500 pL lysis buffer (2 mM EDTA, 400 mM NaCl, 10 mM Tris-HCL pH 8.0, 0.6% SDS) and 2 pL proteinase K (10 mg/mL), and then it was transferred to a bead beating tube (BioSpec Products Inc., Bartlesville, OK, USA) containing 200 pL of beads (0.1 mm zirconia/silica beads; BioSpec Products Inc., Bartlesville, OK, USA). The tubes were incubated at 56 °C for 2 h with shaking at 600 rpm. The tubes were then shaken in a cell Disrupter (MiniBeadbeater-8; Biospec Products) at 3,200 g for 60 sec and incubated on ice for 10 min. To remove foam and beads from the inner walls, the tubes were centrifuged at 5,000 x g for 30 sec. The samples were briefly vortexed to ensure that any DNA adhering to small solid particles was not lost when the lysate was transferred. All liquid contents from the bead-beating tube were transferred to 1.5-mL microcentrifuge tubes (Eppendorf tubes; Sigma-Aldrich) and 500 pL of 100% ethanol was added. The tubes were left standing for 2 min at room temperature before being vortexed for 5 seconds and centrifuged at 18,000 x g for 5 min. at 18 °C. The supernatant was discarded and the pellet was washed once in 200 pL 70% ethanol by resuspension and centrifugation under the same conditions as mentioned above. Next, the pellet was resuspended in 50 pL of sterile distilled water. The tubes were placed in a dry heating block (Eppendorf; Germany) at 100 °C for 5 min. The solution was briefly centrifuged at full speed (16,000 x g for 30 sec) to remove any contaminating material. Finally, a 25-pL aliquot of the supernatant was placed into a new Eppendorf tube (Eppendorf tubes; Sigma-Aldrich) to be used as a template for qPCR.
Molecular detection and culture confirmation of MAP by qPCR. To detect MAP, either directly from faecal pools or confirmation of positive MGIT tubes, a qPCR protocol previously reported by Salgado et al (2013) was used. Briefly, the target was the insertion element IS900. The qPCR mixture included 5 pl DNA template, 10 pl TaqMan Universal Master Mix (Roche, Indianapolis, IN), 0.2 pM IS900 primers, 0.1 pM probe (Roche, Indianapolis, IN), and water for a total volume of 20 pl. Primer sequences for IS900, which amplified a 63-nucleotide fragment of the IS900 gene target, were 5'-GACGCGATGATCGAGGAG-3' (left) and 5'-GGGCATGCTCAGGATGAT-3' (right). The probe sequence was TCGCCGCC. The reactions were carried out in a Roche LightCycler System version 2.0 (Roche, Indianapolis, IN, USA) under the following standard conditions: one cycle at 95°C for 10 min; 45 cycles with three steps of 95 °C for 10 s, 60 °C for 30 s, and 72 °C for 1 s; and a final cooling step at 40 °C for 30 s. Negative (Mix and Water PCR-grade) and positive (Mycobacterium avium subsp. paratuberculosis ATCC 19698) PCR controls were included.
STATISTICAL ANALYSIS
The information collected through the questionnaire and the ELISA test was first analysed descriptively and then analytically. These analyses were carried out using a bivariable and multivariable logistic regression, to explore the influence of multiple flock management practices to MAP seroprevalence. The calculation of the 95% confidence interval for the prevalence results was performed. Also, the calculation of the true prevalence was made using the WinEpi platform, available at www.winepi.net. An unconditional mixed-effects logistic regression analysis, grouped by flock to account for clustering, was also performed. The criteria of Hosmer-Lemeshow (P<0.25) was used to retain variables for the multivariable model. Statistical analysis was carried out using the Stata 12.0 software (StataCorp LP, College Station, Texas, USA). For the exploration of the influence of multiple flock managements practices to MAP seroprevalence, the unit of analysis was the individual and the case definition of a positive flock was the one that had at least one positive result to the ELISA test, culture or qPCR.
RESULTS
FLOCK CHARACTERISTICS
Flock characteristics and management practices explored and then considered as predictors for the risk factor assessment are presented in table 1. The study flocks were all pasture-based and mostly had an area of less than 2 hectares and the flock average population (> 1 year) was 155 animals. The flock distribution was composed mainly of small flocks with limited access to veterinary assistance. Katahdin, Dorper and Santa Ines were the predominant breeds. Most of the farms managed other ruminant species in their facilities, mainly cattle, and in 40.3% of the cases these species shared paddocks. A 61.1% of the flocks shared roads with neighbouring flocks and 52.6% spread slurry onto pastures. Purchase of animals was highly frequent in the study flocks. Most of the interviewed owners/managers reported not having heard about the disease before and not having seen paratuberculosis-symptomatic animals in their flocks in the last 2 years.
SEROPREVALENCE
Eight per cent (37/456, IC: 5.5-10.5) of the serum samples were positive, and at least one or more seropositive animals were detected in 70.8% (17/24, IC: 51.2-90.0) of the flocks. Positive ELISA results among regions were 70, 100, and 63.6% in the Metropolitan Area, Northern and Eastern region of Antioquia, respectively (table 2). The intra-flock seroprevalence ranged from 0 to 21.4% (data not shown).
FAECAL CULTURE
Overall, 78.8% (71 /90) of faecal pools showed positive results after confirmation by qPCR. MAP positive pools (one or more) were detected in 83.3% (IC: 67.3-99.3) of the flocks. The apparent prevalence values among different regions were 100, 67 and 72.7% in the Metropolitan Area, Northern and Eastern region, respectively (table 3).
qPCR OF FAECAL POOLS
qPCR informed 25 (27,7%) positive pools out of 90
faecal pools tested. Forty-six per cent (IC: 24.3-67.3) of the flocks showed MAP positive results in one or more of the analysed pools. The apparent prevalence among regions based on qPCR results of pools were 40, 100 and 36,4% in the Metropolitan Area, Northern and Eastern regions, respectively (table 3).
aVariables used for the multivariable analysis (P<0.25).
*The distribution refers to the percentage that each value represents.
|Faecal culture||qPCR|
|Region||Flocks||Pools||Positive pools||Flock positive resulta||Flock apparent prevalence||Positive pools||Flock Positive resulta||Flock apparent Prevalence|
|Metropolitan Area||10||38||37||10||100||10||4||40|
|Northern||3||13||6||2||67||5||3||100|
|Eastern||11||39||28||8||72.7||10||4||36.4|
|Total||24||90||71||20||83.3||25||11||45.8|
aRefers to flocks in which at least one pool resulted MAP positive by culture or PCR.
FACTORS ASSOCIATED WITH THE MAP SEROLOGICAL STATUS
Among the nine risk factors explored in the univariable analysis, four (flock population, sharing paddocks, sharing roads, use of dewormer) were associated with the seropositivity to MAP infection (P≤0.25) and were eligible for their inclusion in the final model (table 1).
However, no significant variables were obtained in the final model when the multivariable logistic regression analysis was carried out.
DISCUSSION
This study was carried out using a combination of direct and indirect diagnostic methods to detect MAP infection in sheep in the Metropolitan Area, Northern and the Eastern regions of the province of Antioquia, Colombia. The combination of ELISA, direct qPCR and faecal culture assured an accurate MAP infection detection in the study regions. To the author´s knowledge, this is the first epidemiological report on sheep MAP infection in Colombia, and one of the few studies in Latin America performed in small ruminants to estimate MAP prevalence and to explore management practices associated with MAP seropositivity.
The results show that antibodies against MAP are widespread in the study regions, which in general means that MAP infection had progressed significantly in this animal population, and the serological results indicate a significant proportion of individuals are in the late phase of this infection and, as such, efficient MAP shedders. The latter finding agrees with the results reported elsewhere in the same ruminant species (Attili et al 2011, Stau 2012, Moron-Cedillo et al 2013, Bauman et al 2016a, Morales-Pablos et al 2020). Additionally, the observed flock-level prevalence of MAP infection in sheep flocks could be considered as high, in comparison with what has been reported by Bauman et al (2016b) in sheep flocks in Canada, using direct and indirect diagnostic methods (ELISA, bacterial culture and qPCR). According to a systematic review for Latin America and the Caribbean, the prevalence of this infection in sheep is 16% (7.9-24.1%) at an individual level, and the prevalence in sheep at the flock level was not reported due to the lack of studies that met the inclusion criteria; the high heterogeneity detected in overall prevalence estimations could be attributed to the high diversity in study design, the variable quality of measures, or the test used (Fernández-Silva et al 2014).
Although no seropositive animals were identified in some flocks (data not shown) in this study. These animals were likely to be found in the early stages of infection and the levels of antibodies may have not been detectable (Nielsen 2010). The location and flock management practices also may limit the contact between neighbouring flocks and different animal species in these regions since the paddocks are distant to each other or the flocks are isolated, and the entry of other animals is not allowed. Nevertheless, MAP infection shows similar behaviour in the study regions, e.g. few seropositive animals being observed within each flock, but many flocks with at least one seropositive animals (Coelho et al 2007, Stau et al 2012, Morales-Pablos et al
2020, Khamassi Khbou et al 2020).
The lower rate of positive results obtained by qPCR in comparison to culture was expected as previously reported (Alinovi et al 2009, Plain et al 2014) for sheep. The different diagnostic sensitivity between qPCR and culture is mainly explained by the fact that the direct qPCR tool has to deal with faecal sample inhibitors for polymerase activity (Monteiro et al 1997, Thornton and Passen 2004) as well as intermittent MAP shedding (Whitlock et al 2000). On the other hand, culture can address these difficulties along the culture period due to the bacteria replication rate (Harris and Barletta 2001). It is well known that liquid media based on Middlebrook 7H9 Broth base such as BACTEC MGIT system has shown better results to grow several strains of Mycobacterium avium subsp. paratuberculosis than conventional media (HEYM) (Gumber and Whittington, 2007). However, the combination of both MAP detection tools improves the capacity of detection of infected flocks.
Even though some flocks showed only negative qPCR and culture results, it is also likely that the results for the tests did not necessarily mean that the animals were not infected, and it may be that the shedding phase has not started (infected animal in a noninfectious phase) yet (McKenna et al 2006, Nielsen 2010). The high MAP prevalence obtained in this study is consistent with what has been previously confirmed for cattle in the same region (Fernández-Silva et al 2011, Ramírez et al 2011, Correa-Valencia et al 2016, Correa-Valencia et al 2019). In addition, the absence of strategies, programs, or projects to prevent or control the infection and the historic management practices that allow the entrance and spread of the infection in the different animal productions help to explain the findings.
The small number of observations and the fit for several factors may explain the lack of association in the multivariate linear or logistic regression analysis (Hackshaw 2008, Figueiredo et al 2013). Also, the number of positive and negative outcomes in the observed data influence the precision of the estimates of coefficients in the model. It has been suggested that the dataset should contain a minimum of 10(k+1) positive outcomes where k is the number of predictors in the model in order to adequately fit the model (Dohoo et al 2010). These reasons can explain why no significant variables were obtained in the final model.
In the last decade, the arrival of sheep in the study regions has occurred for purposes of restocking and genetic improvement due to the increase of lamb consumption in the region. However, these animals are purchased without quarantine or any diagnostic test. Most of these animals come from different provinces of Colombia where the prevalence of paratuberculosis infections is unknown. In the absence of biosecurity practices, a single animal (clinically or subclinically sick) is enough to infect a flock and disseminate MAP among other flocks. The paratuberculosis prevalence may increase as the biosecurity practices intended for the prevention and control of infection are not being implemented or executed in the
flocks (Morales-Pablos et al 2020).
In conclusion, MAP infection is widespread in sheep flocks of the study regions and the combination of several diagnostic tests were necessary to achieve a more accurate diagnosis of MAP infection. Further studies including a larger sample size are needed to identify the risk factors associated with MAP infection in sheep in Colombia. | https://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0719-81322021000200083&lng=en&tlng=en |
You can direct seed cucumber or start plants indoors 2-3 weeks before the last rains after all danger of frost is gone before planting them outdoors. plant in rows 1-2 meters apart, Sow seeds 50-70 centimeter apart. Seeds should be planted 1 centimeter deep, place 2 seeds, You may want to thin the seedlings as they grow. planted in rows you can encouraged them to climb trellises.
cucumbers are ready for seeds when they are fully ripe, the color changes from green to yellow, harvest only when thy are completely yellow (as in pic), and store in dark cool place until fruits are soft to the touch.
Clean work area with water and rag, removing any debris and inspecting for rogue seeds that may have been left previously.
Bring the variety that is to be processed and place tub on table next to the work area.
Estimate quantity of seed that will be extracted and choose a holding tub representative of the expected amount. For example, use a short deli tub for a low number of fruits, a large deli tub for a good number of fruits, and a small bin for a large quantity of fruits.
Chose a knife and make a slice in the cucumber. Be mindful when cutting into the fruit that seeds are not damaged in the process. This is more crucial when processing fruits like cucumbers, but a good habit to get into!
Break fruit open the rest of the way with hands. Place one half back into the tub and hold onto the half that will be processed immediately.
With fingers, squish around the inside of the cucumber, loosening the seeds and creating a nice juicy environment. The point of this process is to separate the seeds from the placenta and pulp, allowing as little pulp as possible into the holding container.
Allow seeds to enter the holding container as more juice is created, removing pulp as created, and placing in compost bin. This is a somewhat gentle process and the flesh of the fruit should not be disturbed.
When seeds have been removed, place the flesh and rind into compost bin.
If a fruit is very ripe and losing integrity, do the best you can to remove all seeds, sometimes this is very tricky, and if some pulp or flesh drops in the holding container, that’s ok. Water processing goes quicker the cleaner the seed is in the holding container, but sometimes it can’t be helped.
Take holding container and label to the sink and add a small amount of warm water. The water helps break down the sugars in the membrane surrounding the seed and softens the pulp.
Set holding container and label on table in the processing room and leave sit for 1-2 days.
Wipe down the sink area.
Choose a holding container of cucumber seed that has sat for 1-2 days and bring to sink.
Place one of the towels next to sink.
Add water to the holding container until bucket is almost full. Swish seed and debris with hand, squishing the mush between fingers.
Allow the water to settle. Good cucumber seed will sink to the bottom of the holding container, while light/empty seed floats to the top along with the jelly coating.
Gently pour off the water and anything that has floated to the top of the bucket. If there is a large concentration of jelly coats on the surface, they may either be poured off or scooped out with a small hand-held sieve.
Repeat steps 4 and 5 until everything that floats has been removed and the good seed is contained at the bottom of the container.
Transfer seed from holding container to sieve.
Turn hose on and begin spraying seed up, down, back and forth, circular, removing juices, sugars, and other debris. If there is larger debris present that will not pass through holes, remove it with fingers. Sometimes the pulp is particularly persistent; in which case the seed will need to be transferred to original holding container, add water to seeds, place back in sieve, and begin spraying again to clean seed. This process can take anywhere from 45 seconds to minutes.
Once seed is clean, debris has been removed, and the jelly around the seed is no longer present, turn hose off and wipe the bottom of the sieve on the towel to remove excess water.
If working with a small amount of seed, grab a coffee filter and place the seed in the filter. Spread seed out with fingers to encourage drying.
When working with a large amount of seed, find a colander in that is of suitable size (seed won’t sneak through) and place seed in colander.
Take the processed seed, with label, place the seeds ON the a screen and cover with another screen in front of fan.
Clean up the sink area, any colander/sieves that were used in the process, and proceed with the next variety.
Seed will need to be stirred every day to ensure proper drying. Drying usually takes 7-10 days. Seed moisture can either be checked by feel with hands, or a seed can be cracked between teeth—you are looking for a hard dry seed coat and an embryo that is full. This comes with practice! | https://www.nativityseeds.com/en/knowledge-base/cat/guides/post/instructions-for-growing-processing-cucumber-seed/ |
Creative Informatics is delighted to announce recipients of funding for its third round of Small Grants for researchers based at the University of Edinburgh and Edinburgh Napier University. The grants offer academic researchers support with research costs of £5,000 for original research on the Creative Industries over a six-month period. After a robust selection process from a range of high-quality applications, we have selected the following nine recipients for grants:
John Paul Vargheese, Lecturer, School of Computing (Edinburgh Napier University), Marianne Wilson and Katherine Stephen (Edinburgh Napier University): Exploring the relationship between listener receptivity and the source of music recommendations. Music streaming platforms often employ algorithmic recommender systems in addition to expert curated playlists. These are intended to assist listeners with navigating extensive libraries, discovering new content and helping artists establish new audiences. Listeners may also receive word-of-mouth music recommendations from their peers based on knowledge of each other’s preferences and personal experiences. This project aims to investigate if the source of a music recommendation influences a listener’s receptivity, particularly their intentions of engaging further with a recommended artist, for example through album streaming, live show attendance or merchandise purchase. To achieve this, researchers plan to conduct an exploratory study designed to measure participants’ receptivity between three perceived sources of music recommendations (algorithmic, editorial-curated and peer recommendation). The researchers believe this research may provide insights into how those within the creative industries can optimise their ability to generate a sustainable revenue from their work.
Dr Dimitris Papageorgiou, (Edinburgh Napier University): Improvisation Technologies and Creative Machines: The Performer-Instrument Relational Milieu. This practice-led, artistic research study traces theoretical and practical understandings that explore the technicity and performance-practice of musical improvisation and builds upon the lead’s prior research on the fields of free improvisation, contemporary music notation, and interactive computer music to create a new, software-based generative musical system (pre-alpha, alpha). The project also invites internationally renowned performers/improvisers to test and to play with the developed system, and explores via its practice-led methodology whether the HCI performance setting promotes a dialogic and co-produced improvisational musical space.
Martin Disley (University of Edinburgh): Investigative Computing: An Aesthetic Approach. In recent years, sociotechnical critiques of machine learning systems have shed light on the myriad ways in which essentialist thinking both governs, and is operationalised in, the construction of machine learning models. Whilst the development of facial recognition models have been underscored by extensive critical work on their inherent fallibility, models centred on the voice remain an understudied area of AI ethics research despite falling foul of the same essentialising impulse. Through the production of an experimental short film, this project seeks to open up the social and technical limitations of these models for a general audience. In doing so we hope to articulate the potential of investigative computing to be used as part of creative practice to disseminate technical knowledge to non-technical researchers or to enable non-technical researchers to explore technical systems.
Samantha Vettese (Edinburgh Napier University): Measuring the capabilities of new, sustainable materials in digital and traditional craft practices towards repeatability and a widening of their usage. A big challenge in developing by-products of industrial processes into novel materials for craftspeople is the lack of shared knowledge on the possibilities and best practices for using them. Better understanding of how novel materials could be recycled and reused could lead to less wasteful industrial processes overall. This project proposes to gather knowledge about the best ways to use recyclable materials out of the heads of individual creatives and makers and into a repository which can be disseminated across the creative industries as a whole.
Dr Zack Moir, Director of the Applied Music Centre (Edinburgh Napier University): Mountain Bikes Data and Music Creation. This project explores ways in which an interdisciplinary approach to sports and the arts can encourage engagement in both areas. We will look at ways in which we can encourage integrated engagement in artistic endeavours and healthy activity through the sonification of health and activity data from mountain biking. This will involve a range of activities including working with younger riders to collect and discuss health data and running music-making workshops with participants to help them to learn about and make music from their health/activity data. This is novel and innovative because it meaningfully links engagement with sport/exercise and music/arts education. This project will provide opportunities for people to actively engage in the creation/development of music through practical engagement in sports and exercise.
Tod Van Gunten, Lecturer in Economic Sociology (University of Edinburgh): Music streaming as global cultural diffusion. This research builds on prior Creative Informatics-funded work to develop models on of the global spread of songs on a music streaming platform. Building on previous research on radio play, the project seeks to assess the extent to which globally successful songs are instant hits (a likely sign of coordinated marketing campaigns) or more slowly spreading “sleeper hits.” The research will result in descriptive statistical models and visualisation tools demonstrating patterns of musical spread around the world.
Haftor Medbøe, Head of Screen & Performing Arts (Edinburgh Napier University)
Iain McGregor, School of Computing (Edinburgh Napier University)
Andrew Bell, School of Geosciences (University of Edinburgh): The Sound Beneath Our Feet. Taking as a starting point the curation and treatment of sonic data collected during the 16 year eruption of Tungurahua volcano, Ecuador, the project team will produce a range of creative responses to data to be presented in an immersive, surround sound setting. In exploring creative potentials of seismic data our aim is to make meaningful links between disciplines of science and humanities that provide new pathways to access while providing additional knowledge in respective fields. Processes and methods will be fully documented for dissemination to relevant communities and the project artefact will be showcased through a number of public engagement activities.
Iain McGregor, (Edinburgh Napier University): SOVRA: Subjective Orientation in VR audio. This project will involve establishing a method for capturing listeners’ experiences of spatial audio in VR. Whilst wearing a Head Mounted Display (HMD), sounds will be presented to listeners who will be asked to indicate the relative position in both orientation and depth. Traditional methods of capturing spatial listening experiences have focused on physical anatomy, in the erroneous belief that hearing is identical to listening. There are many factors that affect auditory spatial perception, from levels of listening, reproduction hardware, noise floor, presbycusis, general health, cognitive load, levels of distraction, type of content and even the choice of task, amongst many others. Having the ability to identify where listeners perceive a sound emanating from can also utilised for diagnosing hearing impairments as well as head injuries. Both VR simulations and AR support systems could be tested under different cognitive loads to develop novel forms of sonification to improve reaction times, spatial orientation, and navigation.
Dr Michael Wamposzyc, (Edinburgh Napier University): Visualisation of Metadata in 2D/3D Digital Cuneiform Artefacts. Cuneiform is an ancient writing system that was first used in around 3400 BC and is distinguished by its 3D imprinted, wedge-shaped reed marks on clay artefacts. The particular interest within the topic relates to the epistemic issues of 2D/3D data translation and representation. Two specific issues that the proposed creative prototype pilot will examine are: visualisation of the metadata of collected artefacts and visualisation of AI processes indicating/predicting the content of damaged tablet passages. The proposed interdisciplinary project will utilise hybrid creative practices and starts a collaboration with the Digital Pasts Lab (Israel) between Dr Michael Wamposzyc (PI) and Dr Shai Gordin (CI). The outcomes will investigate epistemic applications of data in the creative and cultural sector and ways of unlocking the value of archives and data sets.
Throughout their projects, researchers will share their findings through blog posts on the Creative Informatics website and other public engagement activities. Projects must complete by December 2022 and Creative Informatics will host a showcase in early 2023 to publicly share the outcomes of this new research. | https://creativeinformatics.org/research/meet-our-2022-small-research-grant-holders/ |
CROSS-REFERENCE TO RELATED APPLICATIONS
0001 This application is a continuation of U.S. patent application Ser. No. 09/587,423 filed on Jun. 5, 2000. The disclosure of the above application is incorporated herein by reference.
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION
SUMMARY OF THE INVENTION
0002 This invention relates to the detection of cracks in manufactured parts. More particularly, this invention relates to the detection of surface cracks in parts made of materials having a highly reflective surface and a low emissivity.
0003 Manufacturers are often forced to optimize the design of parts that they manufacture in an effort to increase the efficiency of devices employing the parts. To that end, the design of the parts are optimized through the use of lighter weight materials and through the elimination of material that does not strengthen the part. The design optimization process assumes that the part is manufactured to exacting specifications.
0004 Oftentimes, the optimized part includes complex geometric and curved surfaces which need to be manufactured. Manufacturers must identify parts that fail to meet the specifications in an efficient manner to control manufacturing costs. To reduce weight, manufacturers employ lighter weight materials such as aluminum, titanium and silicon which have a high reflectivity and a low emissivity. In order for these parts to perform as intended, the parts must be manufactured without surface irregularities such as cracks, pits, scratches and holes. If the surface irregularities are not found, the part may fail early which can be problematic if the part is critical to the safe operation of the device.
0005 For example, aircraft manufactures currently manufacture complex geometric and curved aluminum stringers which can be 110 feet in length and 12 inches wide. These stringers are considered to be a critical structure of aircraft wings. After being manufactured, the stringer is transferred to a liquid penetrant inspection station for quality control. A liquid penetrant is applied to a surface of the part that is to be inspected. An operator inspects the part for surface irregularities. This technique is time consuming which increases the cost of the stringer and the time required to manufacture the stringer. The liquid penetrant that is applied to the stringer also contaminates the part.
0006 Infrared crack detection involves applying a highly emissive material to a surface of the part to be inspected. The part is heated uniformly using a flash lamp or other suitable devices. The part absorbs or couples some of the energy contained in the flash. The coupled energy causes the entire part to radiate heat. If the part was manufactured perfectly, a thermal gradient for the part would vary in a continuous manner. Using an infrared camera, the thermal gradient of the part is measured. Abrupt discontinuities in the thermal gradient identify the surface irregularities such as surface cracks, pits, scratches and holes. This method fails to identify smaller cracks, scratches, and holes because the heat energy flows over the opening.
0007 Unfortunately, the conventional infrared crack detection method cannot be used on aluminum having a thickness greater than approximately . Aluminum has relatively high heat dissipation characteristic. Therefore, if the aluminum part has a thickness, greater than , the heat generated by the flash lamp is quickly absorbed and dissipated by the aluminum. The thermal gradient does not adequately and reliably identify smaller surface irregularities such as cracks, pits, scratches and holes. If a higher energy source such as a laser is used, the emissive material is vaporized. If the highly emissive material is not used, an extremely high power laser is required to heat or couple with aluminum.
0008 A detection system for identifying surface irregularities includes a part that is made of a material having a relatively high reflectivity in a relatively low emissivity. A laser source generates a laser beam. A scanning device scans the laser beam across a surface of the part. A surface irregularity radiates energy absorbed from said laser beam. An infrared receiver is directed at the surface of the part. The infrared receiver generates an infrared signal of the surface. A display that is connected to the infrared receiver displays the infrared signal to identify the surface irregularity.
0009 In one feature of the invention, the scanning device directs the laser beam onto the part in an incident angle that is substantially perpendicular to the surface of the part.
0010 In other features of the invention, the laser beam has a beam diameter that is approximately 50 microns or less. The infrared camera is oriented at a first angle relative to a line perpendicular to the surface of the part. The first angle is greater than 20 degrees and less than 30 degrees.
0011 In still other features of the invention, a part transport device moves the part in a first direction. The scanning device scans the surface of the part in a second direction that is perpendicular to the first direction. An image processing module that is associated with the computer performs image processing on the infrared signal. A peak detection image processor associated with the computer identifies a surface irregularity by comparing the infrared signal generated by the infrared receiver through a threshold signal. The peak detection processor declares a surface irregularity when the infrared signal exceeds the threshold signal.
0012 In yet another feature of the invention, the scanning device includes a first mirror and a second mirror. At least one of the first and second mirrors is rotatable and includes a plurality of facets for scanning the laser beam across the surface of the part.
0013 Other objects, features and advantages will be readily apparent from the specification, the claims, and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
0014FIG. 1 illustrates an infrared crack detection system according to the present invention;
0015FIG. 2 illustrates a functional block diagram of an infrared crack detection system according to the invention;
0016FIG. 3 illustrates a functional block diagram of a peak storage image processor according to the present invention; and
0017FIG. 4 illustrates a peak storage image output by a display.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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0018 Referring now to FIG. 1, an infrared crack detection system that identifies surface irregularities such as surface cracks, pits, scratches and holes in a part is shown. The part includes a plurality of surfaces , and which are to be inspected. The part is made of a highly reflective material with a relatively low emissivity. Materials such as aluminum, titanium, and silicon (for example silicon solar panels) have a relatively high reflectivity and low emissivity. The infrared crack detection system includes one or more lasers , , and which generate a laser beam , , and . A beam diameter of the laser beams , and is preferably 50 microns or less. Preferably the lasers , and operate between 1 and 10 W. A part transport system (FIG. 2) moves the part in a direction indicated by arrow .
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0019 The infrared crack detection system further includes mirrors , , , , and . The mirrors , , , , and include fixed and/or movable mirrors as will be described further below. One or more infrared linear detectors , , and sense light that lies in an infrared region of the light spectrum. Alternately, infrared cameras can be used. A computer includes a display , a microprocessor (FIG. 2), memory (FIG. 2) one or more input devices such as a keyboard and a mouse .
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0020 Preferably, the infrared linear detector is positioned at an angle (identified at ) relative to a line (identified at ) that is perpendicular to the surface . The infrared linear detector has a linear field of view . The infrared linear detector is positioned at an angle relative to a line that is perpendicular to the surface in a similar manner. The infrared linear detector has a linear field of view of the surface . The infrared linear detector is positioned at an angle (identified at ) relative to a line (identified at ) that is perpendicular to the surface . The infrared linear detector has a linear field of view .
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0021 In use, the laser generates the laser beam that is reflected by the mirrors and onto the surface . The mirrors and scan the laser beam across the surface of the part . Preferably, the laser beam strikes the surface at an angle that is approximately perpendicular to the surface . One or both of the mirrors and can be a multifaceted surface that is rotated to scan the laser beam linearly across the surface in a conventional manner (for example across a line that is within the field of view of the infrared camera ).
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0022 The laser generates the laser beam that is directed by the mirrors and onto the surface . The mirrors and scan the laser beam across the surface of the part . Preferably the laser beam strikes the surface at an angle that is approximately perpendicular to the surface . One or both of the mirrors and can be a multi-faceted surface that is rotated to scan the laser beam in a conventional manner.
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0023 The mirrors and direct the laser beam onto the surface . The mirrors and scan the laser beam across the surface of the part . Preferably the mirrors and scan the laser beam across a line . Preferably the laser beam strikes the surface at an angle that is perpendicular to the surface . One or both of the mirrors and can be a multi-faceted surface that is rotated to scan the laser beam in a conventional manner.
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0024 Because the part is made of a highly reflective material, approximately 90 to 95 percent of the energy of the laser beam is reflected. When a surface irregularity such as a crack, pit, scratch and/or hole is encountered, a lower percentage of the laser beam is reflected. The difference in energy is absorbed by the surface irregularity. The surface irregularity becomes a cavity radiator. As can be appreciated, the infrared crack detection system does not depend on the identification of abrupt discontinuities in a thermal gradient of the material. The coupling of the laser in areas surrounding the surface irregularity are irrelevant in the present invention and critical in conventional infrared crack detection.
0025 Localized radiation from the surface irregularity will be detected by the infrared camera. The localized radiation is caused by the surface imperfection absorbing more of the laser beam energy than the surrounding area. As a result, the surface irregularity will also radiate more energy than the surrounding area. The surface imperfection behaves like a cavity radiator or a small gray body. The following formula represents the energy emitted by a gray body:
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0026 is the energy emitted by gray body, is the Stefan-Boltzmann constant. is the material emissivity. is the angle of the incident laser relative to a line perpendicular to the surface. Where d is the crack depth, ris a distance from a crack axis point inside a cone under consideration and ris crack opening width. Energy radiated by a gray body is described further in Engineering Radiation and Heat Transfer by J. A. Wiebelt, Holt, Rienhart, and Winston, 1966 which is hereby incorporated by reference. Assuming the crack is a cone, F is a configuration factor defined by:
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0027 Referring now to FIG. 2, the infrared crack detection system is illustrated in further detail. The computer includes an input/output interface that is connected to a processor and memory . The memory contains an operating system module , an image processing module and a peak storage image processing module .
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0028 The lasers , and (collectively identified at in FIG. 2) are connected to the input/output interface . The infrared linear detectors , and (collectively identified at ) are also connected to the input/output interface . The display , the keyboard and the mouse are also connected to the input/output interface . The computer can also be connected to a manufacturing system through a local area network , a wide area network , and/or an input/output network such as an Ethernet network. The manufacturing system is connected to a part transport system such as a conveyor. The manufacturing system can also be connected to one or more position sensors that generate signals that identify a location of parts travelling on the part transport device . The computer is connected to one or more other input/output devices such as printers, scanners, etc. The position sensors may be attached as one of the I/O devices if desired. The image processing module performs conventional image processing on outputs of the infrared cameras , and . Alternately, the output of the infrared linear detectors , and can be output directly to the display .
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0029 The peak storage image processing module is illustrated further in FIG. 3. Outputs of the infrared linear detectors , and (collectively identified at ) are input to a comparator . A threshold signal generator generates a threshold signal which identifies surface irregularities that are sufficiently large. The threshold signal is set high enough to eliminate noise and surface irregularities that are within specifications for the part. A laser position generator generates a position signal related to the current scanning position of the laser beam on the part. The position signals and comparator output identify which portions of the part have the surface irregularities for output directly to the display or for storage. When the signal generated by the infrared camera exceeds the threshold signal, the comparator generates a signal that is output to the data capture module .
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0030 The threshold signal generator , the laser position generator , the comparator , and the data capture module can be implemented as a stand alone module, a device or software executed by the processor.
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0031 Referring now to FIG. 4, the computer collects data related to a part from the data capture module for output on the display . The computer generates a graphical representation of a part at and a graphical representation of a surface irregularity at . The location of the surface irregularity relative to the part is provided. X and Y coordinates can be provided along with zoom in, zoom out, and other functions generally provided by toolbars and menu bars with conventional drawing or design programs.
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0032 In use, the computer or a switch (not shown) actuates the lasers , and which generate the laser beams. The mirrors scan the lasers across the surfaces of the part as the part transport moves the part. The infrared cameras generate infrared images of the scanned surfaces of the part. As the laser beam is incident upon surface irregularities, energy is radiated by the surface irregularities. The radiation by the surface irregularity raises the temperature of the surface irregularity above the ambient temperature of the surroundings. The infrared camera captures an infrared image that is output to a display and/or image processing is performed. Surface irregularities are readily identifiable. When coupled with position sensors, the system identifies and stores the location of the surface irregularities relative to the part.
0033 As can be appreciated, the present invention solves the problem of identifying surface irregularities in parts made of highly reflective materials with low emissivity. Surface irregularities can be identified in a production line in real time without contamination or other time consuming processes. Surface irregularities in the order of 10 microns can be detected. In the production of stringers, the system can identify surface irregularities while the part is being transported by the part transport system at 30 inches per minute.
0034 Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the present invention can be implemented in a variety of forms. Therefore while this invention has been described in connection with particular examples thereof, the true scope of the invention should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, the specification and the following claims. | |
The Collaborative International Dictionary of English v.0.48:
Merry \Mer"ry\ (m[e^]r"r[y^]), n. (Bot.) A kind of wild red cherry. [1913 Webster]The Collaborative International Dictionary of English v.0.48:
Merry \Mer"ry\, a. [Compar. Merrier; superl. Merriest.] [OE. merie, mirie, murie, merry, pleasant, AS. merge, myrige, pleasant; cf. murge, adv.; prob. akin to OHG. murg, short, Goth. gama['u]rgjan to shorten; cf. L. murcus a coward, who cuts off his thumb to escape military service; the Anglo-Saxon and English meanings coming from the idea of making the time seem short. Cf. Mirth.] 1. Laughingly gay; overflowing with good humor and good spirits; jovial; inclined to laughter or play; sportive. [1913 Webster] They drank, and were merry with him. --Gen. xliii. 34. [1913 Webster] I am never merry when I hear sweet music. --Shak. [1913 Webster] 2. Cheerful; joyous; not sad; happy. [1913 Webster] Is any merry? let him sing psalms. --Jas. v. 13. [1913 Webster] 3. Causing laughter, mirth, gladness, or delight; as, a merry jest. "Merry wind and weather." --Spenser. [1913 Webster] Merry dancers. See under Dancer. Merry men, followers; retainers. [Obs.] [1913 Webster] His merie men commanded he To make him bothe game and glee. --Chaucer. [1913 Webster] To make merry, to be jovial; to indulge in hilarity; to feast with mirth. --Judg. ix. 27. [1913 Webster] Syn: Cheerful; blithe; lively; sprightly; vivacious; gleeful; joyous; mirthful; jocund; sportive; hilarious. [1913 Webster]WordNet (r) 3.0 (2006):
merry adj 1: full of or showing high-spirited merriment; "when hearts were young and gay"; "a poet could not but be gay, in such a jocund company"- Wordsworth; "the jolly crowd at the reunion"; "jolly old Saint Nick"; "a jovial old gentleman"; "have a merry Christmas"; "peals of merry laughter"; "a mirthful laugh" [syn: gay, jocund, jolly, jovial, merry, mirthful] 2: offering fun and gaiety; "a festive (or festal) occasion"; "gay and exciting night life"; "a merry evening" [syn: gay, festal, festive, merry] 3: quick and energetic; "a brisk walk in the park"; "a lively gait"; "a merry chase"; "traveling at a rattling rate"; "a snappy pace"; "a spanking breeze" [syn: alert, brisk, lively, merry, rattling, snappy, spanking, zippy]Moby Thesaurus II by Grady Ward, 1.0: | http://www.freedictionary.org/?Query=merry |
Gerald Brisco is a professional wrestler whose real name is Gerald Floyd Brisco. Gerald Brisco was born on September 19, 1946, in Oklahoma City, Oklahoma, United States. This page will examine Gerald Brisco’s total career net worth.
Gerald Brisco married Barbara Brisco, is the parent of 2, including Wes Brisco, and is part of the Jack Brisco (brother). In the ring, Gerald Brisco was trained by Jack Brisco. Billed from Blackwell, Oklahoma Gerald Brisco has had a interesting career in wrestling which debuted in 1969 and which ended in 1985.
Some of the signature moves employed by Gerald Brisco included the Sleeper hold, and Multiple suplex variations. In terms of music, Gerald Brisco has entered the ring to “Real American” by Rick Derringer (WWF; 1999; while teaming with Pat Patterson (wrestler)).
Wrestlers’ income differ depending on league, experience, and skill. According to the league, the average professional wrestler earns nearly $500,000 a year. But some earn more than a million dollars. Separately, non-professional part-time wrestlers earn at most $1000 or less per match.
So what is Gerald Brisco’s net worth in 2018? Our estimate for Gerald Brisco’s net worth in 2018 is: | https://www.thesquander.com/gerald-brisco-net-worth-2018-what-wrestler-worth-1593732517 |
Section A (20 Marks)
Write short notes on any four of the following:
Section B (30 marks)
(Attempt any three)
1. What do you mean by functions? Write a note on supply and demand functions.
2. An investor wants to invest `15,000 in two types of bonds. He earns 12% in first type and 15% in the second. Find his investment in each of his total earning is `1950.
3. Given the following column vectors
Find (i) A+B, (ii) A+B+C, (iii) 2A-B+C
4. A company is faced with the problem of assigning five different machines to five different jobs with a view to minimize total cost. The costs (in thousands) are estimated and shown in the following table:
Jobs
Machines
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2
3
4
5
I
2.5
6
II
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7
III
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8
IV
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9
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V
Section C (50 marks)
(Attempt all questions. Every question carries 10 marks)
Read the case “Constructing Payoff Table” and answer the following questions:
Constructing Payoff Table
A company wants to increase its production beyond its existing capacity. It has finally arrived at two approaches to increase the capacity (1) Expansion, at a cost of ` 80 Lakh or (2) Modernization at a cost of ` 50 Lakh. Both approaches would require 8 months for implementation. The Board of Directors feels that during implementation and thereafter the demand will either be very high or moderate. The probability for very high demand is estimated as 0.35 and for moderate it is 0.65. If demand is very high, expansion would result additional profit of 120 Lakh, but on the other hand modernization would bring additional 60 Lakh only. It is estimated that when demand is moderate, the comparable profit would be 70 Lakh and 50 Lakh for modernization.
Questions
1. Construct the Payoff (Profit) Table.
2. What is the optimum strategy for the company?
3. Calculate EMV and EVPI.
4. Calculate EOL.
5. Summarize the case-study in your own words. | http://academiclub.com/features-prodect.php?id=394 |
FROM RPD — On Sunday, March 23, 2014, the Reno Police Department responded to the Flamingo Motel, 520 N. Center St., #207 on the report of a deceased person inside the room.
Upon arrival, officers found a victim obviously deceased and in a state of decomposition indicating that he had died several days earlier; however, a time frame could not be definitively identified.
An autopsy was performed and numerous stab wounds were located, lending a preliminary ruling as the manner of death being a homicide.
Paperwork belonging to the suspect (listed below) was located in the room and further investigation revealed that he, the suspect, had been arrested by Reno Police on March 9th, 2014 after he showed up at the police station and called 911 requesting assistance.
At that time, he had quite a bit of blood on his person and some injuries that were bleeding, but did not give any discernible information about a location of a crime or victim.
Thus, officers were not able to develop any information that the Flamingo or the victim were involved. Ultimately, he was arrested for misuse of 911 and booked into the Washoe County Jail, where he currently remains.
With the assistance of the Washoe County Crime Lab, DNA testing was performed on March 25 and 26, on the clothing the suspect was wearing on March 9, and the victim’s DNA was located in numerous areas.
This information, along with the comments made to 911 and the officers on scene of the original call on March 9th, the Reno Police Department was able to develop probable cause for the arrest of the suspect for the charge of murder. The suspect has been additionally charged and remains in the Washoe County Jail.
He is the only known suspect at this time; however, if anyone has any information about the incident or the suspect, please call the Reno Police Department.
Suspect: Lee, Tony D. DOB: 12-5-1968. Charges: Open Murder.
This Is Reno is your source for award-winning independent, online Reno news and events since 2009. We are locally owned and operated. | https://thisisreno.com/2014/03/death-ruled-murder-suspect-custody/ |
This is one of the reasons why the consortium was created: the resident is actually the owner of the public space, and the members of Olifantenpad would like to know what happens if we also designate and address the resident as owner.
The consortium will be created in 2021, when the engineering consultancy Sweco together with Dutch Design Week invites designers to design the meeting room of the future in a What If challenge. Search for the limits of the technical possibilities and color outside the lines, is the motto.
Elephant Path takes up the challenge: An urban psychologist, a spatial designer, a lighting designer, a VR expert and an expert in neurofeedback join forces in a search for other ways to engage people and explore how technology can serve this purpose. can stand. (During the People’s Information Symposium in November, they gave an insight into their working method.)
Practice
As an example, lighting designer Ellen de Vries cites a study in Eindhoven, where different lighting scenarios were used in a specific environment. The municipality wanted a scientific infrastructure, and it had to fit into the city’s digital twin, a virtual environment where innovative ideas can be tested.
“We let people go through scenarios with a headband: young and old, male and female, resident and professional. We measure the neurofeedback via brain waves, how they react to what they experience. Not literally from “I like this or not”, but you can detect patterns.” In conversations with the city psychologist, a qualitative component was added to the collected data. In addition, extreme situations were tested, for example using color, to record what it causes in the brain.
recognizable surroundings
Olifantenpad continues in the same way in another experiment involving a large, stony (school) square in Rotterdam, which needs to be redesigned. In the virtual environment, three variants have been designed with input from the residents.
These basic environments are set up with data available in the Netherlands, so that a recognizable environment is created for the resident. He chooses a variant and specifies adjustments: the elements come from Rotterdam’s style book and can therefore actually be used in the space in question, such as tiles, votives, furniture, greenery, playground equipment and light poles. There’s also a night mode so you can move lights around or turn them on and off. The resident is an expert by experience and knows what is needed, where, also in terms of lighting, the tank is.
Surprising results
It provides a lot of surprising information. “That residents find other things important than professionals, that men and women can experience stress due to different reasons, that people feel good when their brain understands the perspective in a split second,” De Vries summarizes a few findings. | https://lawnservicemaintenance.com/2023/01/06/engaging-citizens-in-design-with-virtual-reality-and-neurofeedback/ |
CROSS-REFERENCE TO RELATED APPLICATIONS
TECHNICAL FIELD
This application claims priority to Chinese Application No. 201910906113.0, filed on Sep. 24, 2019 and entitled “Method and Apparatus for Outputting Information,” the entire disclosure of which is hereby incorporated by reference.
Embodiments of the present disclosure relate to the field of computer technology, and specifically to a method and apparatus for outputting information.
BACKGROUND
At present, lidar ranging has been widely used in the fields, such as autonomous driving and auxiliary driving, due to its excellent characteristics and strong adaptability to the external environment. In the application scenarios of data collected by a lidar, many parameters often need to be adjusted. Manual adjustment of these parameters is often time-consuming and labor-consuming.
SUMMARY
Embodiments of the present disclosure propose a method and apparatus for outputting information.
In a first aspect, an embodiment of the present disclosure provides a method for outputting information, including: acquiring obstacle data collected by a vehicle during a driving process, the obstacle data including point cloud data and image data; determining a plurality of time thresholds based on a preset time threshold value range; executing following processing for each time threshold: identifying obstacles included in each point cloud frame in the point cloud data and each image frame in the image data respectively; determining a similarity between an obstacle in each point cloud frame and an obstacle in each image frame; determining, in response to the similarity being greater than a preset similarity threshold, whether a time interval between the point cloud frame and the image frame corresponding to two similar obstacles is less than the time threshold; and processing recognized obstacles based on a determining result, to determine a number of obstacles; and determining, based on obtained a plurality of numbers, and outputting a target time threshold.
In some embodiments, the determining a plurality of time thresholds based on a preset time threshold value range includes: selecting a plurality of points in the time threshold value range at a preset time interval, as the plurality of time thresholds.
In some embodiments, the processing recognized obstacles based on a determining result, to determine a number of obstacles includes: associating, in response to the time interval being less than the time threshold, the two similar obstacles as the same obstacle; and non-associating, in response to the time interval being greater than or equal to the time threshold, the two similar obstacles as the same obstacle.
In some embodiments, the method further includes: fusing, in response to the associating the two similar obstacles as the same obstacle, the two similar obstacles based on the point cloud frame and the image frame corresponding to the two similar obstacles.
In some embodiments, the determining, based on obtained a plurality of numbers, and outputting a target time threshold includes: determining a number-time threshold curve based on the plurality of numbers and a time threshold corresponding to each number; and determining a slope of the curve at each time threshold, and determining the target time threshold based on each slope.
In some embodiments, the determining the target time threshold based on each slope includes: determining a maximum value of absolute values of the slopes; and using a time threshold corresponding to the maximum value as the target time threshold.
In a second aspect, an embodiment of the present disclosure provides an apparatus for outputting information, including: a data acquiring unit configured to acquire obstacle data collected by a vehicle during a driving process, the obstacle data including point cloud data and image data; a threshold determining unit configured to determine a plurality of time thresholds based on a preset time threshold value range; a data processing unit configured to execute following processing for each time threshold: identifying obstacles included in each point cloud frame in the point cloud data and each image frame in the image data respectively; determining a similarity between an obstacle in each point cloud frame and an obstacle in each image frame; determining, in response to the similarity being greater than a preset similarity threshold, whether a time interval between the point cloud frame and the image frame of two similar obstacles is less than the time threshold; and processing recognized obstacles based on a determining result, to determine a number of obstacles; and a target determining unit configured to determine, based on obtained a plurality of numbers, and output a target time threshold.
In some embodiments, the threshold determining unit is further configured to: select a plurality of points in the time threshold value range at a preset time interval, as the plurality of time thresholds.
In some embodiments, the data processing unit is further configured to: associate, in response to the time interval being less than the time threshold, the two similar obstacles as the same obstacle; and non-associate, in response to the time interval being greater than or equal to the time threshold, the two similar obstacles as the same obstacle.
In some embodiments, the apparatus further includes: a data fusing unit configured to fuse, in response to the associating the two similar obstacles as the same obstacle, the two similar obstacles based on the point cloud frame and the image frame corresponding to the two similar obstacles.
In some embodiments, the target determining unit is further configured to: determine a number-time threshold curve based on the plurality of numbers and a time threshold corresponding to each number; and determine a slope of the curve at each time threshold, and determine the target time threshold based on each slope.
In some embodiments, the target determining unit is further configured to: determine a maximum value of absolute values of the slopes; and use a time threshold corresponding to the maximum value as the target time threshold.
In a third aspect, an embodiment of the present disclosure provides an electronic device, the electronic device including: one or more processors; and a storage apparatus, storing one or more programs, where the one or more programs, when executed by the one or more processors, cause the one or more processors to implement any embodiment of the method according to the first aspect.
In a fourth aspect, an embodiment of the present disclosure provides a computer readable medium, storing a computer program thereon, where the computer program, when executed by a processor, implements any embodiment of the method according to the first aspect.
The method and apparatus for outputting information provided by some embodiments of the present disclosure may first acquire obstacle data collected by a vehicle during a driving process, the obstacle data may include point cloud data and image data; then may determine a plurality of time thresholds based on a preset time threshold value range; may execute processing for each time threshold: identifying obstacles included in each point cloud frame in the point cloud data and each image frame in the image data respectively; then determining a similarity between an obstacle in each point cloud frame and an obstacle in each image frame; determining, in response to the similarity being greater than a preset similarity threshold, whether a time interval between the point cloud frame and the image frame of two similar obstacles is less than the time threshold; and processing recognized obstacles based on a determining result, to determine the number of obstacles; and finally determine, based on obtained a plurality of numbers, and output a target time threshold. The method of the present embodiment may determine the time threshold during the obstacle data processing based on the number of obstacles, thereby achieving automatic adjustment of the time threshold without the need of manual adjustment.
BRIEF DESCRIPTION OF THE DRAWINGS
After reading detailed description of non-limiting embodiments with reference to the following accompanying drawings, other features, objectives and advantages of the present disclosure will become more apparent.
FIG. 1
is a diagram of an example system architecture in which embodiments of the present disclosure may be implemented;
FIG. 2
is a flowchart of a method for outputting information according to an embodiment of the present disclosure;
FIG. 3
is a schematic diagram of an application scenario of a method for outputting information according to an embodiment of the present disclosure;
FIG. 4
is a flowchart of determining a target time threshold in the method for outputting information according to an embodiment of the present disclosure;
FIG. 5
is a schematic structural diagram of an apparatus for outputting information according to an embodiment of the present disclosure; and
FIG. 6
is a schematic structural diagram of a computer system adapted to implement an electronic device of embodiments of the present disclosure.
DETAILED DESCRIPTION OF EMBODIMENTS
Embodiments of present disclosure will be described below in detail with reference to the accompanying drawings. It should be appreciated that the specific embodiments described herein are merely used for explaining the relevant disclosure, rather than limiting the disclosure. In addition, it should be noted that, for the ease of description, only the parts related to the relevant disclosure are shown in the accompanying drawings.
It should also be noted that some embodiments in the present disclosure and some features in the disclosure may be combined with each other on a non-conflict basis. Features of the present disclosure will be described below in detail with reference to the accompanying drawings and in combination with embodiments.
FIG. 1
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shows an example system architecture in which a method for outputting information or an apparatus for outputting information of embodiments of the present disclosure may be implemented.
FIG. 1
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As shown in , the system architecture may include autonomous vehicles , , and , a network , and a server . The network serves as a medium providing a communication link between the autonomous vehicles , , and , and the server . The network may include various types of connections, such as wired or wireless communication links, or optical cables.
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The autonomous vehicles , , and may be provided with various sensors, such as a lidar or an image collecting apparatus, to collect point cloud data or image data of a driving environment of the autonomous vehicles , , and . The autonomous vehicles , , and may be further provided with various electronic devices, such as a navigation apparatus, an autonomous vehicle controller, an anti-lock braking system, and a braking force distribution system. The autonomous vehicles , , and may be vehicles that include an autonomous driving mode, including both fully autonomous vehicles and vehicles that can be switched to the autonomous driving mode.
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The server may be a server that provides various services, such as a back-end server for processing obstacle data collected by the vehicles , , and . The back-end server can process, e.g., analyze, received data, such as the obstacle data, and return the processing result (e.g., a target time threshold) to the vehicles , , and .
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It should be noted that the server may be hardware, or may be software. When the server is hardware, the server may be implemented as a distributed server cluster composed of a plurality of servers, or be implemented as a single server. When the server is software, the server may be implemented as a plurality of software programs or software modules (e.g., software programs or software modules for providing distributed services), or may be implemented as a single software program or software module. This is not specifically limited here.
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It should be noted that the method for outputting information provided by some embodiments of the present disclosure may be executed by the vehicles , , and , or may be executed by the server . Accordingly, the apparatus for outputting information may be provided in the vehicles , , and , or may be provided in the server .
FIG. 1
It should be understood that the numbers of vehicles, networks, and servers in are merely illustrative. Any number of vehicles, networks, and servers may be provided based on actual requirements.
FIG. 2
200
With further reference to , a process of a method for outputting information according to an embodiment of the present disclosure is shown. The method for outputting information includes following steps.
201
Step : acquiring obstacle data collected by a vehicle during a driving process.
105
FIG. 1
In the present embodiment, an executing body (e.g., the server shown in ) of the method for outputting information may acquire the obstacle data collected by the vehicle during the driving process through a wired connection or connection. The obstacle data may include point cloud data and image data. The point cloud data may include a plurality of point cloud frames, and each point cloud frame may include a plurality of point cloud points. The image data may include a plurality of image frames. The vehicle may be provided with a lidar sensor and a camera, to collect point cloud data and image data of a surrounding environment of the vehicle during driving.
202
Step : determining a plurality of time thresholds based on a preset time threshold value range.
In the present embodiment, the executing body may acquire a preset time threshold value range, and the time threshold value range may be determined based on values of a plurality of preset time thresholds. For example, the plurality of preset time thresholds may include 0.5 ms, 1.0 ms, and 1.5 ms. Each time threshold may be set by a skilled person based on his own experience. The executing body may obtain the plurality of time thresholds by taking values at intervals of a preset duration in the time threshold value range. For example, the time threshold value range is 0.5 ms-1.5 ms. The executing body may take a value every 0.1 ms, and then may obtain the plurality of time thresholds, which are 0.5 ms, 0.6 ms, 0.7 ms, . . . , 1.5 ms, respectively. Alternatively, the executing body may also randomly select the plurality of time thresholds from the above time threshold value range.
FIG. 2
In some alternative implementations of the present embodiment, the executing body may determine the plurality of time thresholds through the following steps that are not shown in : selecting a plurality of points in the time threshold value range at a preset time interval, as the plurality of time thresholds.
In the present implementation, the executing body may select the plurality of points in the time threshold value range at the preset time interval, as the plurality of time thresholds. Specifically, the time threshold value range may be divisible by the time interval.
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Step : executing the following processing steps - for each time threshold.
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After obtaining the plurality of time thresholds, the executing body may perform the processing steps - for each time threshold.
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Step : identifying obstacles included in each point cloud frame in point cloud data and each image frame in image data respectively.
The executing body may identify the obstacles included in each point cloud frame in the point cloud data, and may also identify the obstacles included in each image frame in the image data, using a pre-trained obstacle recognition model or an obstacle recognition algorithm (e.g., a point cloud segmentation algorithm, or a feature extraction algorithm). Specifically, the executing body may input each point cloud frame in the point cloud data or each image frame in the image data into the obstacle recognition model from an input side, such that recognized obstacles may be obtained from an output side of the obstacle recognition model.
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Step : determining a similarity between an obstacle in each point cloud frame and an obstacle in each image frame.
After recognizing the obstacles included in each point cloud frame and each image frame, the executing body may compute the similarity between the obstacle in each point cloud frame and the obstacle in each image frame. Specifically, the executing body may extract features of the obstacles and compute the similarity between the obstacles based on a distance between feature vectors.
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Step : determining, in response to the similarity being greater than a preset similarity threshold, whether a time interval between the point cloud frame and the image frame corresponding to two similar obstacles is less than the time threshold.
For each obtained similarity, the executing body may determine whether the similarity is greater than the preset similarity threshold. Here, the similarity threshold may be used for characterizing a degree of similarity between obstacles. If the similarity is greater than the similarity threshold, then the two obstacles are very similar. Then, the executing body may further determine the point cloud frame and the image frame of the two similar obstacles. Then, the time interval between the point cloud frame and the image frame is computed, and whether the above time interval is greater than the time threshold is determined.
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Step : processing recognized obstacles based on a determining result, to determine the number of obstacles.
After obtaining the determining result, the executing body may process the recognized obstacles based on the determining result, to determine the number of obstacles. Specifically, in response to the time interval being less than the time threshold, the executing body may identify the two obstacles as the same obstacle. In response to the time interval being greater than or equal to the time threshold, the executing body may not identify the two obstacles as the same obstacle. It can be understood that if the two obstacles are identified as the same obstacle, then the two obstacles are statisticized as one obstacle, when statisticizing the number of obstacles. If the two obstacles are not identified as the same obstacle, then the two obstacles are statisticized as two obstacles, when statisticizing the number of obstacles. Thus, the number of recognized obstacles can be determined at each time threshold.
FIG. 2
In some alternative implementations of an embodiment, the executing body may determine the number of obstacles in the following ways that are not shown in : associating, in response to the time interval being less than the time threshold, the two similar obstacles as the same obstacle; and non-associating, in response to the time interval being greater than or equal to the time threshold, the two similar obstacles as the same obstacle.
FIG. 2
In some alternative implementations of an embodiment, the above method may further include the following steps that are not shown in : fusing, in response to the associating the two similar obstacles as the same obstacle, the two similar obstacles based on the point cloud frame and the image frame corresponding to the two similar obstacles.
In response to the associating the two similar obstacles as the same obstacle, the executing body may fuse the two similar obstacles based on the point cloud frame and the image frame corresponding to the two similar obstacles. Thus, more accurate obstacle information can be obtained for guiding the driving of the autonomous vehicle.
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Step : determining, based on obtained a plurality of numbers, and outputting a target time threshold.
In the present embodiment, with the increase of the time threshold, the more are the similar obstacles likely to be associated, and the smaller is the number of obtained obstacles. Accordingly, the smaller is the time threshold, the less are the similar obstacles likely to be associated, and the larger is the number of obtained obstacles. Then, the executing body may determine a change rate of the numbers of obstacles based on the obtained numbers, and determine the target time threshold based on the change rate.
FIG. 3
FIG. 3
FIG. 3
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With further reference to , is a schematic diagram of an application scenario of the method for outputting information according to the present embodiment. In the application scenario of , an autonomous vehicle collects point cloud data through a lidar sensor provided thereon, collects image data through a camera provided thereon during a driving process, and sends the point cloud data and the image data to a server . The server performs processing in steps - for the point cloud data and the image data, to determine a target time threshold, and sends the target time threshold to the autonomous vehicle . The autonomous vehicle may fuse obstacles during the driving process based on the target time threshold.
The method for outputting information provided by embodiments of the present disclosure may first acquire obstacle data collected by a vehicle during a driving process, where the obstacle data may include point cloud data and image data; then may determine a plurality of time thresholds based on a preset time threshold value range; may execute processing for each time threshold: identifying obstacles included in each point cloud frame in the point cloud data and each image frame in the image data respectively; then determining a similarity between an obstacle in each point cloud frame and an obstacle in each image frame; determining, in response to the similarity being greater than a preset similarity threshold, whether a time interval between the point cloud frame and the image frame of two similar obstacles is less than the time threshold; and processing recognized obstacles based on a determining result, to determine the number of obstacles; and finally determines, based on obtained a plurality of numbers, and outputs a target time threshold. The method of the present embodiment may determine the time threshold during the obstacle data processing based on the numbers of obstacles, thereby achieving automatic adjustment of the time threshold without the need of manual adjustment.
FIG. 4
FIG. 4
400
With further reference to , a process of determining a target time threshold in the method for outputting information according to an embodiment of the present disclosure is shown. As shown in , the method for outputting information according to the present embodiment may determine a target time threshold through the following steps.
401
Step : determining a number-time threshold curve based on a plurality of numbers and a time threshold corresponding to each number.
In the present embodiment, the executing body may obtain a number-time threshold curve with the time threshold as the X axis, with the number of obstacles as the Y axis, based on the obtained plurality of numbers and the time threshold corresponding to each number.
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Step : determining a slope of the curve at each time threshold.
Then, the executing body may determine the slope of the curve at each time threshold based on an equation of the curve. The slope here can represent a change rate of the numbers of obstacles. The executing body may determine the target time threshold based on the obtained each slope. For example, the executing body may use a time threshold with a maximum absolute value of the slope as the target time threshold. Alternatively, the executing body may compute an average value of the slopes, and then use a time threshold corresponding to the average value as the target time threshold. It can be understood that the target time threshold is determined based on the curve, and may be the same as, or different from, the preset time threshold.
403
Step : determining a maximum value of absolute values of the slopes.
In the present embodiment, the executing body may determine the maximum value of the absolute values of the slopes. It can be understood that the less is the time threshold, i.e., the larger is the number of obstacles, the more is the false detection likely to take place, and the higher is the false detection rate. The greater is the time threshold, i.e., the smaller is the number of obstacles, the more is the missed detection likely to take place, and the higher is the missed detection rate. Here, a point corresponding to the maximum value is a point at which the number of obstacles decreases fastest, and is also an intersection point of a false detection rate curve and a missed detection rate curve.
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Step : using a time threshold corresponding to the maximum value as a target time threshold.
The executing body may use the time threshold corresponding to the maximum value as the target time threshold.
The method for outputting information provided by embodiments of the present disclosure may automatically determine an appropriate time threshold, thereby reducing the workload in the process of obstacle data processing.
FIG. 5
FIG. 2
With further reference to , as an implementation of the method shown in the above figures, an embodiment of the present disclosure provides an apparatus for outputting information. An embodiment of the apparatus may correspond to an embodiment of the method shown in . The apparatus may be specifically applied to various electronic devices.
FIG. 5
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As shown in , the apparatus for outputting information of the present embodiment includes: a data acquiring unit , a threshold determining unit , a data processing unit , and a target determining unit .
501
The data acquiring unit is configured to acquire obstacle data collected by a vehicle during a driving process. The obstacle data include point cloud data and image data.
502
The threshold determining unit is configured to determine a plurality of time thresholds based on a preset time threshold value range.
503
The data processing unit is configured to execute the following processing for each time threshold: identifying obstacles included in each point cloud frame in the point cloud data and each image frame in the image data respectively; determining a similarity between an obstacle in each point cloud frame and an obstacle in each image frame; determining, in response to the similarity being greater than a preset similarity threshold, whether a time interval between the point cloud frame and the image frame corresponding to two similar obstacles is less than the time threshold; and processing recognized obstacles based on a determining result, to determine the number of obstacles.
The target determining unit is configured to determine, based on obtained a plurality of numbers, and output a target time threshold.
502
In some alternative implementations of the present embodiment, the threshold determining unit may be further configured to: select a plurality of points in the time threshold value range at a preset time interval, as the plurality of time thresholds.
503
In some alternative implementations of the present embodiment, the data processing unit may be further configured to: associate, in response to the time interval being less than the time threshold, the two similar obstacles as the same obstacle; and non-associate, in response to the time interval being greater than or equal to the time threshold, the two similar obstacles as the same obstacle.
500
FIG. 5
In some alternative implementations of the present embodiment, the above apparatus may further include a data fusing unit that is not shown in , and is configured to fuse, in response to the associating the two similar obstacles as the same obstacle, the two similar obstacles based on the point cloud frame and the image frame corresponding to the two similar obstacles.
504
In some alternative implementations of the present embodiment, the target determining unit may be further configured to: determine a number-time threshold curve based on the plurality of numbers and a time threshold corresponding to each number; and determine a slope of the curve at each time threshold, and determine the target time threshold based on each slope.
504
In some alternative implementations of the present embodiment, the target determining unit may be further configured to: determine a maximum value of absolute values of the slopes; and use a time threshold corresponding to the maximum value as the target time threshold.
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FIG. 2
It should be understood that the unit to unit recorded in the apparatus for outputting information correspond to the steps in the method described in respectively. Therefore, the operations and features described above for the method for outputting information also apply to the apparatus and the units included therein. The description will not be repeated here.
FIG. 6
FIG. 6
600
Referring to below, a schematic structural diagram adapted to implement an electronic device of some embodiments of the present disclosure is shown. The electronic device shown in is merely an example, and should not limit the functions and scope of use of some embodiments of the present disclosure.
FIG. 6
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As shown in , the electronic device may include a processing apparatus (e.g., a central processing unit, or a graphics processor) , which may execute various appropriate actions and processes in accordance with a program stored in a read-only memory (ROM) or a program loaded into a random access memory (RAM) from a storage apparatus . The RAM further stores various programs and data required by operations of the electronic device . The processing apparatus , the ROM , and the RAM are connected to each other through a bus . An input/output (I/O) interface is also connected to the bus .
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FIG. 6
FIG. 6
In general, the following apparatuses may be connected to the I/O interface : an input apparatus including a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, or the like; an output apparatus including a liquid crystal display device (LCD), a speaker, a vibrator, or the like; a storage apparatus including a magnetic tape, a hard disk, or the like; and a communication apparatus . The communication apparatus may allow the electronic device to exchange data with other devices through wireless or wired communication. While shows the electronic device having various apparatuses, it should be understood that it is not necessary to implement or provide all of the apparatuses shown in the figure. More or fewer apparatuses may be alternatively implemented or provided. Each block shown in may represent an apparatus, or represent a plurality of apparatuses as required.
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In particular, according to some embodiments of the present disclosure, the process described above with reference to the flow chart may be implemented in a computer software program. For example, some embodiments of the present disclosure include a computer program product, which includes a computer program that is tangibly embedded in a computer readable medium. The computer program includes program codes for executing the method as shown in the flow chart. In such an embodiment, the computer program may be downloaded and installed from a network via the communication apparatus , or be installed from the storage apparatus , or be installed from the ROM . The computer program, when executed by the processing apparatus , implements the above functions as defined by the method of some embodiments of the present disclosure. It should be noted that the computer readable medium according to some embodiments of the present disclosure may be a computer readable signal medium or a computer readable medium or any combination of the above two. An example of the computer readable medium may include, but is not limited to: electric, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, elements, or a combination of any of the above. A more specific example of the computer readable medium may include, but is not limited to: electrical connection with one or more pieces of wire, a portable computer disk, a hard disk, a random access memory (RAM), a read only memory (ROM), an erasable programmable read only memory (EPROM or flash memory), an optical fiber, a portable compact disk read only memory (CD-ROM), an optical memory, a magnetic memory, or any suitable combination of the above. In some embodiments of the present disclosure, the computer readable medium may be any tangible medium containing or storing programs, which may be used by, or used in combination with, a command execution system, apparatus or element. In some embodiments of the present disclosure, the computer readable signal medium may include a data signal in the base band or propagating as a part of a carrier wave, in which computer readable program codes are carried. The propagating data signal may take various forms, including but not limited to an electromagnetic signal, an optical signal, or any suitable combination of the above. The computer readable signal medium may also be any computer readable medium except for the computer readable medium. The computer readable medium is capable of transmitting, propagating or transferring programs for use by, or used in combination with, a command execution system, apparatus or element. The program codes contained on the computer readable medium may be transmitted with any suitable medium, including but not limited to: wireless, wired, optical cable, RF medium, etc., or any suitable combination of the above.
The computer readable medium may be included in the above electronic device; or a stand-alone computer readable medium without being assembled into the electronic device. The computer readable medium stores one or more programs. The one or more programs, when executed by the electronic device, cause the electronic device to: acquire obstacle data collected by a vehicle during a driving process, the obstacle data including point cloud data and image data; determine a plurality of time thresholds based on a preset time threshold value range; execute following processing for each time threshold: identifying obstacles included in each point cloud frame in the point cloud data and each image frame in the image data respectively; determining a similarity between an obstacle in each point cloud frame and an obstacle in each image frame; determining, in response to the similarity being greater than a preset similarity threshold, whether a time interval between the point cloud frame and the image frame of two similar obstacles is less than the time threshold; and processing recognized obstacles based on a determining result, to determine the number of obstacles; and determine, based on obtained a plurality of numbers, and output a target time threshold.
A computer program code for executing operations in some embodiments of the present disclosure may be compiled using one or more programming languages or combinations thereof. The programming languages include object-oriented programming languages, such as Java, Smalltalk or C++, and also include conventional procedural programming languages, such as “C” language or similar programming languages. The program code may be completely executed on a user's computer, partially executed on a user's computer, executed as a separate software package, partially executed on a user's computer and partially executed on a remote computer, or completely executed on a remote computer or server. In a circumstance involving a remote computer, the remote computer may be connected to a user's computer through any network, including local area network (LAN) or wide area network (WAN), or be connected to an external computer (for example, connected through the Internet using an Internet service provider).
The flow charts and block diagrams in the accompanying drawings illustrate architectures, functions and operations that may be implemented according to the systems, methods and computer program products of the various embodiments of the present disclosure. In this regard, each of the blocks in the flowcharts or block diagrams may represent a module, a program segment, or a code portion, said module, program segment, or code portion including one or more executable instructions for implementing specified logical functions. It should be further noted that, in some alternative implementations, the functions denoted by the blocks may also occur in a sequence different from the sequences shown in the figures. For example, any two blocks presented in succession may be executed substantially in parallel, or they may sometimes be executed in a reverse sequence, depending on the functions involved. It should be further noted that each block in the block diagrams and/or flow charts as well as a combination of blocks in the block diagrams and/or flow charts may be implemented using a dedicated hardware-based system executing specified functions or operations, or by a combination of dedicated hardware and computer instructions.
The units involved in some embodiments of the present disclosure may be implemented by software, or may be implemented by hardware. The described units may also be provided in a processor, for example, described as: a processor including a data acquiring unit, a threshold determining unit, a data processing unit, and a target determining unit. The names of the units do not constitute a limitation to such units themselves in some cases. For example, the data acquiring unit may be further described as “a unit configured to acquire obstacle data collected by a vehicle during a driving process.”
The above description only provides an explanation of embodiments of the present disclosure and the technical principles used. It should be appreciated by those skilled in the art that the inventive scope of the present disclosure is not limited to the technical solutions formed by the particular combinations of the above-described technical features. The inventive scope should also cover other technical solutions formed by any combinations of the above-described technical features or equivalent features thereof without departing from the concept of the present disclosure. Technical schemes formed by the above-described features being interchanged with, but not limited to, technical features with similar functions disclosed in the present disclosure are examples. | |
Summer Kid's Gardening Club
The Cholmondeley Kids Gardening Club offers little gardeners a chance to learn about the growing of vegetables and flowers. At Cholmondeley we are committed to encouraging children to take part in gardening activities, and we are delighted to offer this our fourth and final session of the season.
Our session today Wednesday 23rd August will give children the opportunity to take part in and learn about activities such as seed sowing, planting, harvesting vegetables, and growing and picking flowers. As well as learning about the importance of encouraging wildlife into the garden. Children who take part in these sessions will have the benefit of seeing the seasonal changes to the plot, as well as reaping what they sow!
There is no charge for children taking part in the Garden Club, but normal garden entry fees apply. Limited spaces so booking is essential. Children attending should meet the Gardener supervising the session at the Tea Room. | http://www.cholmondeleycastle.com/events/article/summer-kids-gardening-club/ |
Weak MHD turbulence consists of waves that propagate along magnetic field lines, in both directions. When two oppositely directed waves collide, they distort each other, without changing their respective energies. Each wave suffers many collisions before cascading; by contrast, in strong MHD turbulence, waves cascade on the same timescale at which they collide. "Imbalance" means that more energy is going in one direction than the other. In general, MHD turbulence is unbalanced. Yet unbalanced MHD cascades are not understood. For example, turbulence in the solar wind is observed to be unbalanced, so solar wind turbulence will not be understood until a theory of the imbalanced cascade is developed. We solve weak MHD turbulence that is unbalanced. Of crucial importance is that the energies going in both directions are forced to equalize at the dissipation scale. This "pinning" of the energy spectra was discovered by Grappin and coworkers. It affects the entire inertial range. Weak MHD turbulence is particularly interesting because perturbation theory is applicable. Hence, it can be described with a simple kinetic equation. Galtier and coworkers derived this kinetic equation. We present a simpler, more physical derivation, based on the picture of colliding wavepackets. In the process, we clarify the role of the zero-frequency mode. We also explain why Goldreich & Sridhar claimed that perturbation theory is inapplicable, and why this claim is wrong. (Our "weak" is equivalent to Goldreich & Sridhar's "intermediate.") We perform numerical simulations of the kinetic equation to verify our claims. We construct simplified model equations that illustrate the main effects. Finally, we show that a large magnetic Prandtl number does not have a significant effect, and that hyperviscosity leads to a pronounced bottleneck effect. | https://www.scholars.northwestern.edu/en/publications/imbalanced-weak-magnetohydrodynamic-turbulence |
This article is about human ageing. For other uses, see Ageing (disambiguation).
Ageing (British English) or aging (American English) is the accumulation of changes in a person over time. Ageing in humans refers to a multidimensional process of physical, psychological, and social change. Some dimensions of ageing grow and expand over time, while others decline. Reaction time, for example, may slow with age, while knowledge of world events and wisdom may expand. Research shows that even late in life, potential exists for physical, mental, and social growth and development. Ageing is an important part of all human societies reflecting the biological changes that occur, but also reflecting cultural and societal conventions. Roughly 100,000 people worldwide die each day of age-related causes.
Age is measured chronologically, and a person's birthday is often an important event. However the term "ageing" is somewhat ambiguous. Distinctions may be made between "universal ageing" (age changes that all people share) and "probabilistic ageing" (age changes that may happen to some, but not all people as they grow older including diseases such as type two diabetes). Chronological ageing may also be distinguished from "social ageing" (cultural age-expectations of how people should act as they grow older) and "biological ageing" (an organism's physical state as it ages). There is also a distinction between "proximal ageing" (age-based effects that come about because of factors in the recent past) and "distal ageing" (age-based differences that can be traced back to a cause early in person's life, such as childhood poliomyelitis).
Differences are sometimes made between populations of elderly people. Divisions are sometimes made between the young old (65–74), the middle old (75–84) and the oldest old (85+). However, problematic in this is that chronological age does not correlate perfectly with functional age, i.e. two people may be of the same age, but differ in their mental and physical capacities. Each nation, government and non-government organisation has different ways of classifying age.
Population ageing is the increase in the number and proportion of older people in society. Population ageing has three possible causes: migration, longer life expectancy (decreased death rate), and decreased birth rate. Ageing has a significant impact on society. Young people tend to commit most crimes, they are more likely to push for political and social change, to develop and adopt new technologies, and to need education. Older people have different requirements from society and government as opposed to young people, and frequently differing values as well. Older people are also far more likely to vote, and in many countries the young are forbidden from voting. Thus, the aged have comparatively more political influence.
Recent scientific successes in rejuvenation and extending a lifespan of model animals (mice-2.5 |times, yeast -15 times, nematodes-10 times) and discovery of variety of species (including humans of advanced ages) having negligible senescence give hope to achieve negligible senescence (cancel ageing) for younger humans, reverse ageing or at least significantly delay it.
Early observations
The first formal studies of ageing appear to be those of Muhammad ibn Yusuf al-Harawi (1582) in his book Ainul Hayat, published by Ibn Sina Academy of Medieval Medicine and Sciences. This book is based only on ageing and its related issues. The original manuscript of Ainul Hayat was scribed in 1532 by the author Muhammad ibn Yusuf al-Harawi. Four copies of the manuscript survive and were reprinted in an edited and translated version by Hakim Syed Zillur Rahman (2007). The book discusses behavioural and lifestyle factors putatively influencing ageing including diet, environment and housing conditions. Also discussed are drugs that may increase and decrease ageing rates.
SenescenceMain article: Senescence
In biology, senescence is the state or process of ageing. Cellular senescence is a phenomenon where isolated cells demonstrate a limited ability to divide in culture (the Hayflick Limit, discovered by Leonard Hayflick in 1961), while organismal senescence is the ageing of organisms. After a period of near perfect renewal (in humans, between 20 and 35 years of age), organismal senescence is characterised by the declining ability to respond to stress, increasing homeostatic imbalance and increased risk of disease. This currently irreversible series of changes inevitably ends in death. Some researchers (specifically biogerontologists) are treating ageing as a disease. As genes that have an effect on ageing are discovered, ageing is increasingly being regarded in a similar fashion to other geneticly influenced "conditions", potentially "treatable."
Indeed, ageing is not an unavoidable property of life. Instead, it is the result of a genetic program. Numerous species show very low signs of ageing ("negligible senescence"), the best known being trees like the bristlecone pine (however Dr. Hayflick states that the bristlecone pine has no cells older than 30 years), fish like the sturgeon and the rockfish, invertebrates like the quahog and sea anemone and lobster.
In humans and other animals, cellular senescence has been attributed to the shortening of telomeres with each cell cycle; when telomeres become too short, the cells die. The length of telomeres is therefore the "molecular clock," predicted by Hayflick.
Telomere length is maintained in immortal cells (e.g. germ cells and keratinocyte stem cells, but not other skin cell types) by the telomerase enzyme. In the laboratory, mortal cell lines can be immortalised by the activation of their telomerase gene, present in all cells but active in few cell types. Cancerous cells must become immortal to multiply without limit. This important step towards carcinogenesis implies, in 85% of cancers, the reactivation of their telomerase gene by mutation. Since this mutation is rare, the telomere "clock" can be seen as a protective mechanism against cancer. Research has shown that the clock must be located in the nucleus of each cell and there have been reports that the longevity clock might be located in genes on either the first or fourth chromosome of the twenty-three pairs of human chromosomes.
Other genes are known to affect the ageing process. The sirtuin family of genes have been shown to have a significant effect on the lifespan of yeast and nematodes. Over-expression of the RAS2 gene increases lifespan in yeast substantially.
In addition to genetic ties to lifespan, diet has been shown to substantially affect lifespan in many animals. Specifically, caloric restriction (that is, restricting calories to 30-50% less than an ad libitum animal would consume, while still maintaining proper nutrient intake), has been shown to increase lifespan in mice up to 50%. Caloric restriction works on many other species beyond mice (including species as diverse as yeast and Drosophila), and appears (though the data is not conclusive) to increase lifespan in primates according to a study done on Rhesus monkeys at the National Institute of Health (US), although the increase in lifespan is only notable if the caloric restriction is started early in life. Since, at the molecular level, age is counted not as time but as the number of cell doublings, this effect of calorie reduction could be mediated by the slowing of cellular growth and, therefore, the lengthening of the time between cell divisions.
Drug companies are currently searching for ways to mimic the lifespan-extending effects of caloric restriction without having to severely reduce food consumption.
In his book, 'How and Why We Age', Dr. Hayflick notes a contradiction to the caloric restriction longevity increase theory for humans, noting that data from the Baltimore Longitudinal Study of Ageing show that being thin does not favour longevity.
Dividing the lifespan
An animal's life is often divided into various age ranges. However, because biological changes are slow-moving and can vary within one's own species, arbitrary dates are usually set to mark periods of life. The human divisions given below are not valid in all cultures:
- Juvenile [via infancy, childhood, preadolescence, adolescence (teenager)]: 0-19
- Early adulthood: 20-39
- Middle adulthood: 40-59
- Late adulthood: 60+
Ages can also be divided by decade:
Term Age (years, inclusive) Denarian 10 to 19 Vicenarian 20 to 29 Tricenarian 30 to 39 Quadragenarian 40 to 49 Quinquagenarian 50 to 59 Sexagenarian 60 to 69 Septuagenarian 70 to 79 Octogenarian 80 to 89 Nonagenarian 90 to 99 Centenarian 100 to 109 Supercentenarian 110 and older
People from 13 to 19 years of age are also known as teens or teenagers. Tween is an American neologism referring to someone between the ages of 8 and 14. The casual terms "twentysomething", "thirtysomething", etc. are also in use to describe people by decades of age.
Cultural variations
In some cultures (for example Serbian) there are other ways to express age: by counting years with or without including current year. For example, it could be said about the same person that he is twenty years old or that he is in the twenty-first year of his life. In Russian the former expression is generally used, the latter one has restricted usage: it is used for age of a deceased person in obituaries and for the age of an adult when it is desired to show him/her older than he/she is. (Psychologically, a woman in her 20th year seems older than one who is 19 years old.)
Depending on cultural and personal philosophy, ageing can be seen as an undesirable phenomenon, reducing beauty and bringing one closer to death; or as an accumulation of wisdom, mark of survival, and a status worthy of respect. In some cases numerical age is important (whether good or bad), whereas others find the stage in life that one has reached (adulthood, independence, marriage, retirement, career success) to be more important.
East Asian age reckoning is different from that found in Western culture. Traditional Chinese culture uses a different ageing method, called Xusui (虛歲) with respect to common ageing which is called Zhousui (周歲). In the Xusui method, people are born at age 1, not age 0, because conception is already considered to be the start of the life span, and another difference is the ageing day: Xusui grows up at the Spring Festival (aka. Chinese New Year's Day), while Shuo An grows up at one's birthday.
Society
Legal
There are variations in many countries as to what age a person legally becomes an adult.
Most legal systems define a specific ages for when an individual is allowed or obliged to do particular activities. These ages include voting age, drinking age, age of consent, age of majority, age of criminal responsibility, marriageable age, age of candidacy, and mandatory retirement age. Admission to a movie for instance, may depend on age according to a motion picture rating system. A bus fare might be discounted for the young or old.
Similarly in many countries in jurisprudence, the defence of infancy is a form of defence by which a defendant argues that, at the time a law was broken, they were not liable for their actions, and thus should not be held liable for a crime. Many courts recognise that defendants who are considered to be juveniles may avoid criminal prosecution on account of their age, and in borderline cases the age of the offender is often held to be a mitigating circumstance.
Economics and marketing
The economics of ageing are also of great importance. Children and teenagers have little money of their own, but most of it is available for buying consumer goods. They also have considerable impact on how their parents spend money.
Young adults are an even more valuable cohort. They often have an income but few responsibilities such as a mortgage or children. They do not yet have set buying habits and are more open to new products.
The young are thus the central target of marketers. Television is programmed to attract the range of 15 to 35 year olds. Mainstream movies are also built around appealing to the young.
Health care demand
Many societies in Western Europe and Japan, have ageing populations. While the effects on society are complex, there is a concern about the impact on health care demand. The large number of suggestions in the literature for specific interventions to cope with the expected increase in demand for long-term care in ageing societies can be organised under four headings: improve system performance; redesign service delivery; support informal caregivers; and shift demographic parameters.
However, the annual growth in national health spending is not mainly due to increasing demand from ageing populations, but rather has been driven by rising incomes, costly new medical technology, a shortage of health care workers and informational asymmetries between providers and patients.
Even so, it has been estimated that population ageing only explains 0.2 percentage points of the annual growth rate in medical spending of 4.3 percent since 1970. In addition, certain reforms to Medicare decreased elderly spending on home health care by 12.5 percent per year between 1996 and 2000. This would suggest that the impact of ageing populations on health care costs is not inevitable.
Impact on prisons
As of July 2007, medical costs for a typical inmate in the United States might run an agency around $33 per day, while costs for an ageing inmate could run upwards of $100. Most State DOCs report spending more than 10 percent of the annual budget on elderly care. That is expected to rise over the next 10–20 years. Some states have talked about releasing ageing inmates early.
Cognitive effects
Steady decline in many cognitive processes is seen across the lifespan, accelerating from the thirties. Research has focused in particular on memory and ageing, and has found decline in many types of memory with ageing, but not in semantic memory or general knowledge such as vocabulary definitions, which typically increases or remains steady. Early studies on changes in cognition with age generally found declines in intelligence in the elderly, but studies were cross-sectional rather than longitudinal and thus results may be an artefact of cohort rather than a true example of decline. Intelligence may decline with age, though the rate may vary depending on the type, and may in fact remain steady throughout most of the lifespan, dropping suddenly only as people near the end of their lives. Individual variations in rate of cognitive decline may therefore be explained in terms of people having different lengths of life. There are changes to the brain: though neuron loss is minor after 20 years of age there is a 10% reduction each decade in the total length of the brain's myelinated axons.
Coping and well-being
Psychologists have examined coping skills in the elderly. Various factors, such as social support, religion and spirituality, active engagement with life and having an internal locus of control have been proposed as being beneficial in helping people to cope with stressful life events in later life. Social support and personal control are possibly the two most important factors that predict well-being, morbidity and mortality in adults. Other factors that may link to well-being and quality of life in the elderly include social relationships (possibly relationships with pets as well as humans), and health.
Individuals in different wings in the same retirement home have demonstrated a lower risk of mortality and higher alertness and self-rated health in the wing where residents had greater control over their environment, though personal control may have less impact on specific measures of health. Social control, perceptions of how much influence one has over one's social relationships, shows support as a moderator variable for the relationship between social support and perceived health in the elderly, and may positively influence coping in the elderly.
Religion
Religion has been an important factor used by the elderly in coping with the demands of later life, and appears more often than other forms of coping later in life. Religious commitment may also be associated with reduced mortality, though religiosity is a multidimensional variable; while participation in religious activities in the sense of participation in formal and organised rituals may decline, it may become a more informal, but still important aspect of life such as through personal or private prayer.
Self-rated health
Self-ratings of health, the beliefs in one's own health as excellent, fair or poor, has been correlated with well-being and mortality in the elderly; positive ratings are linked to high well-being and reduced mortality. Various reasons have been proposed for this association; people who are objectively healthy may naturally rate their health better than that of their ill counterparts, though this link has been observed even in studies which have controlled for socioeconomic status, psychological functioning and health status. This finding is generally stronger for men than women, though the pattern between genders is not universal across all studies, and some results suggest sex-based differences only appear in certain age groups, for certain causes of mortality and within a specific sub-set of self-ratings of health.
Retirement
Retirement, a common transition faced by the elderly, may have both positive and negative consequences.
Societal impact
Of the roughly 150,000 people who die each day across the globe, about two thirds — 100,000 per day — die of age-related causes. In industrialised nations, the proportion is much higher, reaching 90%.
Societal ageing refers to the demographic ageing of populations and societies. Cultural differences in attitudes to ageing have been studied.
Emotional improvement
Given the physical and cognitive declines seen in ageing, a surprising finding is that emotional experience improves with age. Older adults are better at regulating their emotions and experience negative affect less frequently than younger adults and show a positivity effect in their attention and memory. The emotional improvements show up in longitudinal studies[specify] as well as in cross-sectional studies[specify] and so cannot be entirely due to only the happier individuals surviving.
Successful ageing
The concept of successful ageing can be traced back to the 1950s, and popularised in the 1980s. Previous research into ageing exaggerated the extent to which health disabilities, such as diabetes or osteoporosis, could be attributed exclusively to age, and research in gerontology exaggerated the homogeneity of samples of elderly people.
Successful ageing consists of three components:
- Low probability of disease or disability;
- High cognitive and physical function capacity;
- Active engagement with life.
A greater number of people self-report successful ageing than those that strictly meet these criteria.
Successful ageing may be viewed an interdisciplinary concept, spanning both psychology and sociology, where it is seen as the transaction between society and individuals across the life span with specific focus on the later years of life. The terms "healthy ageing" "optimal ageing" have been proposed as alternatives to successful ageing.
Six suggested dimensions of successful ageing include:
- No physical disability over the age of 75 as rated by a physician;
- Good subjective health assessment (i.e. good self-ratings of one's health);
- Length of undisabled life;
- Good mental health;
- Objective social support;
- Self-rated life satisfaction in eight domains, namely marriage, income-related work, children, friendship and social contacts, hobbies, community service activities, religion and recreation/sports.
Theories
Biological theories
At present, the biological basis of ageing is unknown. Most scientists agree that substantial variability exists in the rates of ageing across different species, and that this to a large extent is genetically based. In model organisms and laboratory settings, researchers have been able to demonstrate that selected alterations in specific genes can extend lifespan (quite substantially in nematodes, less so in fruit flies, and less again in mice). Even in the relatively simple and short-lived organisms, the mechanism of ageing remain to be elucidated. Less is known about mammalian ageing, in part due to the much longer lives in even small mammals such as the mouse (around 3 years).
The US National Institute on Aging currently funds an intervention testing program, whereby investigators nominate compounds (based on specific molecular ageing theories) to have evaluated with respect to their effects on lifespan and age-related biomarkers in outbred mice. Previous age-related testing in mammals has proved largely irreproducible, because of small numbers of animals, and lax mouse husbandry conditions. The intervention testing program aims to address this by conducting parallel experiments at three internationally recognised mouse ageing-centres, the Barshop Institute at UTHSCSA, the University of Michigan at Ann Arbor and the Jackson Laboratory.
Many have argued that life-span, like other phenotypes, is selected.
- Evolutionary Theories: Enquiry into the evolution of ageing aims to explain why almost all living things weaken and die with age. Exceptions such as rockfish, turtles, and naked molerat are highly informative.
- Telomere Theory: Telomeres (structures at the ends of chromosomes) have experimentally been shown to shorten with each successive cell division.. Shortened telomeres activate a mechanism that prevents further cell multiplication. This may be particularly limit in tissues such as bone marrow and the arterial lining where cell division occurs repeatedly throughout life. Importantly though, mice lacking telomerase enzyme do not show a dramatically reduced lifespan, invalidating at least simple versions of the telomere theory of ageing. Mice may be an exception for the theory, as they have long hypervariable telomeres , prolonging the period after which telomere shortening would affect life-span. But wild mouse strains do not, and telomere length in these breeds is unrelated to lifespan
- Reproductive-Cell Cycle Theory: The idea that ageing is regulated by reproductive hormones that act in an antagonistic pleiotropic manner via cell cycle signalling, promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence (dyosis).
Some theories suggest that ageing is a disease. Two examples are
- DNA Damage Theory of Ageing: Known causes of cancer (radiation, chemical and viral) account for about 30% of the total cancer burden and for about 30% of the total DNA damage. DNA damage causes the cells to stop dividing or induce apoptosis, often affecting stem cell pools and hence hindering regeneration. DNA damage is thought to be the common pathway causing both cancer and ageing. It seems unlikely that the estimates of the DNA damage due to radiation and chemical causes has been significantly underestimated. Viral infection would appear to be the most likely cause of the other 70% of DNA damage especially in cells that are not exposed to smoking and sun light. It has been argued, too, that intrinsic causes of DNA damage are more important drivers of ageing.
- Autoimmune Theory: The idea that ageing results from an increase in autoantibodies that attack the body's tissues. A number of diseases associated with ageing, such as atrophic gastritis and Hashimoto's thyroiditis, are probably autoimmune in this way. While inflammation is very much evident in old mammals, even SCID mice in SPF colonies still experience senescence.
Genetic theories
Many theories suggest that ageing results from the accumulation of damage to DNA in the cell, or organ. Since DNA is the formative basis of cell structure and function, damage to the DNA molecule, or genes, can lead to its loss of integrity and early cell death.
Examples include:
- Accumulative-Waste Theory: The biological theory of ageing that points to a buildup of cells of waste products that presumably interferes with metabolism.
- Wear-and-Tear Theory: The very general idea that changes associated with ageing are the result of chance damage that accumulates over time.
- Somatic Mutation Theory: The biological theory that ageing results from damage to the genetic integrity of the body’s cells.
- Error Accumulation Theory: The idea that ageing results from chance events that escape proof reading mechanisms, which gradually damages the genetic code.
Some have argued that ageing is programmed: that an internal clock detects a time to end investing in the organism, leading to death. This ageing-Clock Theory suggests, as in a clock, an ageing sequence is built into the operation of the nervous or endocrine system of the body. In rapidly dividing cells the shortening of the telomeres would provide such a clock. This idea is in contradiction with the evolutionary based theory of ageing.
- Cross-Linkage Theory: The idea that ageing results from accumulation of cross-linked compounds that interfere with normal cell function.
- Free-Radical Theory: The idea that free radicals (unstable and highly reactive organic molecules), or more generally reactive oxygen species or oxidative stress create damage that gives rise to symptoms we recognise as ageing.
- Reliability theory of ageing and longevity: A general theory about systems failure. It allows researchers to predict the age-related failure kinetics for a system of given architecture (reliability structure) and given reliability of its components. Reliability theory predicts that even those systems that are entirely composed of non-ageing elements (with a constant failure rate) will nevertheless deteriorate (fail more often) with age, if these systems are redundant in irreplaceable elements. Ageing, therefore, is a direct consequence of systems redundancy. Reliability theory also predicts the late-life mortality deceleration with subsequent levelling-off, as well as the late-life mortality plateaus, as an inevitable consequence of redundancy exhaustion at extreme old ages. The theory explains why mortality rates increase exponentially with age (the Gompertz law) in many species, by taking into account the initial flaws (defects) in newly formed systems. It also explains why organisms "prefer" to die according to the Gompertz law, while technical devices usually fail according to the Weibull (power) law. Reliability theory allows to specify conditions when organisms die according to the Weibull distribution: organisms should be relatively free of initial flaws and defects. The theory makes it possible to find a general failure law applicable to all adult and extreme old ages, where the Gompertz and the Weibull laws are just special cases of this more general failure law. The theory explains why relative differences in mortality rates of compared populations (within a given species) vanish with age (compensation law of mortality), and mortality convergence is observed due to the exhaustion of initial differences in redundancy levels.
- Mitohormesis: It has been known since the 1930s that restricting calories while maintaining adequate amounts of other nutrients can extend lifespan in laboratory animals. Recently, Michael Ristow's group has provided evidence for the theory that this effect is due to increased formation of free radicals within the mitochondria causing a secondary induction of increased antioxidant defence capacity.
- Misrepair-Accumulation Theory: Wang et al. suggest that ageing is the result of the accumulation of "Misrepair". Important in this theory is to distinguish among "damage" which means a newly emerging defect BEFORE any reparation has taken place, and "Misrepair" which describes the remaining defective structure AFTER (incorrect) repair. The key points in this theory are:
- There is no original damage left unrepaired in a living being. If damage was left unrepaired a life threatening condition (such as bleeding, infection, or organ failure) would develop.
- Misrepair, the repair with less accuracy, does not happen accidentally. It is a necessary measure of the reparation system to achieve sufficiently quick reparation in situations of serious or repeated damage, to maintain the integrity and basic function of a structure, which is important for the survival of the living being.
- Hence the appearance of Misrepair increases the chance for the survival of individual, by which the individual can live at least up to the reproduction age, which is critically important for the survival of species. Therefore the Misrepair mechanism was selected by nature due to its evolutionary advantage.
- However, since Misrepair as a defective structure is invisible for the reparation system, it accumulates with time and causes gradually the disorganisation of a structure (tissue, cell, or molecule); this is the actual source of ageing.
- Ageing hence is the side-effect for survival, but important for species survival. Thus Misrepair might represent the mechanism by which organisms are not programmed to die but to survive (as long as possible), and ageing is just the price to be paid.
Non-biological theories
- Disengagement Theory
- This is the idea that separation of older people from active roles in society is normal and appropriate, and benefits both society and older individuals. Disengagement theory, first proposed by Cumming and Henry, has received considerable attention in gerontology, but has been much criticised. The original data on which Cumming and Henry based the theory were from a rather small sample of older adults in Kansas City, and from this select sample Cumming and Henry then took disengagement to be a universal theory. There are research data suggesting that the elderly who do become detached from society as those were initially reclusive individuals, and such disengagement is not purely a response to ageing.
- Activity theory
- In contrast to disengagement theory, this theory implies that the more active elderly people are, the more likely they are to be satisfied with life. The view that elderly adults should maintain well-being by keeping active has had a considerable history, and since 1972, this has come to be known as activity theory. However, this theory may be just as inappropriate as disengagement for some people as the current paradigm on the psychology of ageing is that both disengagement theory and activity theory may be optimal for certain people in old age, depending on both circumstances and personality traits of the individual concerned. There are also data which query whether, as activity theory implies, greater social activity is linked with well-being in adulthood.
- Selectivity Theory
- mediates between Activity and Disengagement Theory, which suggests that it may benefit older people to become more active in some aspects of their lives, more disengaged in others.
- Continuity Theory
- The view that in ageing people are inclined to maintain, as much as they can, the same habits, personalities, and styles of life that they have developed in earlier years. Continuity theory is Atchley's theory that individuals, in later life, make adaptations to enable them to gain a sense of continuity between the past and the present, and the theory implies that this sense of continuity helps to contribute to well-being in later life. Disengagement theory, activity theory and continuity theory are social theories about ageing, though all may be products of their era rather than a valid, universal theory.
Prevention and reversalSee also: Life extension
Several drugs and food supplements have been shown to retard or reverse the biological effects of ageing in animal models; none has yet been proven to do so in humans. Resveratrol, a chemical found in red grapes, has been shown to extend the lifespan of yeast by 60%, worms and flies by 30% and one species of fish by almost 60%. It does not extend the lifespan of healthy mice but delays the onset of age-related disease and infirmity.
Small doses of heavy water increase fruit-fly lifespan by 30%, but large doses are toxic to complex organisms.
In 2002, a team led by Professor Bruce Ames at UC Berkeley discovered that feeding aged rats a combination of acetyl-L-carnitine and alpha-lipoic acid (both substances are already approved for human use and sold in health food stores) produced a rejuvenating effect. Ames said, "With these two supplements together, these old rats got up and did the macarena. The brain looks better, they are full of energy - everything we looked at looks like a young animal." UC Berkeley has patented the use of these supplements in combination and a company, Juvenon, has been established to market the treatment.
In 2007, researchers at the Salk Institute for Biological Studies, identified a critical gene in nematode worms that specifically links eating fewer calories with living longer. Professor Andrew Dillin and colleagues showed that the gene pha-4 regulates the longevity response to calorie restriction. In the same year Dr Howard Chang of the Stanford University School of Medicine was able to rejuvenate the skin of two-year-old mice to resemble that of newborns by blocking the activity of the gene NF-kappa-B.
In 2008, a team at the Spanish National Cancer Research Center genetically engineered mice to produce ten times the normal level of the telomerase enzyme. The mice lived 26% longer than normal. The same year a team led by Professor Michael O Thorner at the University of Virginia discovered that the drug MK-677 restored 20% of muscle mass lost due to ageing in humans aged 60 to 81. The subjects' growth hormone and insulin-like growth factor 1 (IGF-1) levels increased to that typical of healthy young adults.
In 2009, a drug called rapamycin, discovered in the 1970s in the soil of Easter Island in the South Pacific, was found to extend the life expectancy of 20-month-old mice by up to 38%. Rapamycin is generally used to suppress the immune system and prevent the rejection of transplanted organs. Dr Arlan Richardson of the Barshop Institute said, "I never thought we would find an anti-ageing pill in my lifetime; however, rapamycin shows a great deal of promise to do just that." Professor Randy Strong of the University of Texas Health Science Center at San Antonio said, "We believe this is the first convincing evidence that the ageing process can be slowed and lifespan can be extended by a drug therapy starting at an advanced age."
Also in 2009, the British Journal of Nutrition reported a study at Tufts University in Boston which showed that brain function and motor skills in aged rats could be improved by adding walnuts to their diet. The human equivalent would be to eat seven to nine walnuts per day.
In September 2009, researchers at UC Berkeley discovered they could restore youthful repair capability to muscle tissue taken from men aged 68 to 74 by in vitro treatment with mitogen-activated protein kinase. This protein was found to be essential for the production of the stem cells necessary to repair muscle after exercise and is present at reduced levels in aged individuals.
Ronald A. DePinho, a cancer geneticist at the Dana-Farber Cancer Institute and Harvard Medical School, published a paper in Nature magazine in November 2010 which indicated that the organs of genetically altered mice, designed to activate telomerase after feeding them with a chemical, were rejuvenated.
Shrivelled testes grew back to normal and the animals regained their fertility. Other organs, such as the spleen, liver, intestines and brain, recuperated from their degenerated state. Dr Lynne Cox of Oxford University said, "This paper is extremely important as it provides proof of the principle that short-term treatment to restore telomerase in adults already showing age-related tissue degeneration can rejuvenate aged tissues and restore physiological function."
In this experiment mice were engineered to not produce telomerase naturally but after a chemical "switch" the system would then restore telomerase. Importantly, this chemical does not have the ability to produce telomerase in animals that are not genetically altered. Moreover, telomerase activation is also associated with the growth of cancerous tumours which could prevent anti-ageing treatments using this discovery.
Measure of age
The age of an adult human is commonly measured in whole years since the day of birth. Fractional years, months or even weeks may be used to describe the age of children and infants for finer resolution. The time of day the birth occurred is not commonly considered.
The measure of age has historically varied from this approach in some cultures. In parts of Tibet, age is counted from conception i.e. one is usually 9 months old when one is born.
Age in prenatal development is normally measured in gestational age, taking the last menstruation of the woman as a point of beginning. Alternatively, fertilisation age, beginning from fertilisation can be taken.
Obtaining survey data on ageing
Numerous worldwide health, ageing and retirement surveys contain questions pertaining to pensions. The Meta Data Repository - created by the non-profit RAND Corporation and sponsored by the National Institute on Aging at the National Institutes of Health - provides access to meta data for these questions as well as links to obtain respondent data from the originating surveys.
See also
- Aging movement control
- Ageing brain
- Ageing of Europe
- Biodemography
- Biological immortality
- Death
- Endocrinology of Development
- Gerontology
- Life expectancy
- List of life extension-related topics
- Longevity
- Memory and ageing
- Population ageing
- Retirement
- Senescence
- software ageing
- Stem cell theory of aging
- Supercentenarian
Notes
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Developmental biology EmbryologyEmbryogenesis (Human embryogenesis · Drosophila embryogenesis · Fish embryogenesis) · Polarity in embryogenesis OtherMetamorphosis · Regeneration · Ageing · Model organisms · Compartment · Metamerism Human Development: Biological • Psychological Pre- and perinatalBiologicalPsychological InfancyBiologicalPsychologicalInfant and child psychology ChildhoodBiologicalPsychologicalInfant and child psychology · Preadolescence AdolescenceBiologicalPsychological Young adulthoodPsychological Middle adulthoodBiological MaturityBiologicalAgeing · SenescencePsychological Legal and general definitionsMinor (law) · Infancy · Child · Childhood · Adolescence · Age of majority · Adult Theorists and theories Longevity Terminology IssuesAlleged Brazilian supercentenarians · Longevity claims · Longevity myths · People reported to have lived beyond 130 RecordsOldest people · Oldest people by year of birth · 100 verified oldest people (males · females) · Oldest people by nation · Oldest living people by nation · Longest marriages · Oldest twins CentenariansLiving · Activists, non-profit leaders, and philanthropists · Actors, filmmakers, and entertainers · Artists · Authors, poets, and journalists · Businessmen · Educators, school administrators, social scientists, and linguists · Explorers · Jurists and practitioners of law · Medical professionals · Military commanders · Musicians, composers, and music patrons · Philosophers and theologians · Politicians and government servants · Religious figures · Royalty and nobility · Scientists and mathematicians · Sportspeople · Miscellaneous SupercentenariansLiving · Deaths by year (before 1980 · 1980s · 1990s · 2000 · 2001 · 2002 · 2003 · 2004 · 2005 · 2006 · 2007 · 2008 · 2009 · 2010 · 2011)
By continent (Europe) By country (Australia · Austria · Belgium · Canada · Denmark · Finland · France · Germany · Italy · Japan · Netherlands · Norway · Portugal · Spain · Sweden · United Kingdom · United States)
War-related listsList of the last surviving veterans by war (European · American · Canadian) · World War I (Surviving veterans · Last surviving veterans by country) · Surviving veterans of the Spanish Civil War · Living recipients of the Knight's Cross Non-humanLong-living organisms · List of oldest trees · List of oldest dogsSee also Gerontology · Ageing · Life extension-related topics · Extreme longevity tracking · FOXO3 longevity gene
External links
Media related to Aging at Wikimedia CommonsCategories:
Wikimedia Foundation. 2010. | https://en-academic.com/dic.nsf/enwiki/9326462 |
Writing a survey can be tricky. The way in which you phrase a survey question can influence your data. If you write the questionnaire wrong, your data will end up being skewed. A poorly phrased question or too can turn into a real problem for your results. In order to avoid biasing your research, watch out for the following common missteps:
1. Be clear.
It is very important that a survey is written in a clear and concise manner. Uncomplicated language should be used in a survey to avoid confusing respondents. Avoid technical terms and jargon, instead, make questions as easily understood as possible. It is important to provide adequate definitions and examples where needed throughout your survey.
2. Keep the survey accurate.
A common pitfall on in survey writing can be as simple as asking a question about the respondent’s age. If asking respondents their age and categorizing it, make sure you correctly group the ages. For example, 25-30 and 30-35, this will confuse respondents who are 30 years old as they will not know which group to select and it will also hinder analysis.
3. Ensure your questions are not leading.
Leading questions may influence responses by containing wording that may have an effect on respondents. These questions can work their way into your survey without you realizing as they are hard to catch. For example, asking “how expensive is this product?” will immediately lead the respondent to believe that the product is costly. The survey should aim to be unbiased and ask, “what is the price of the product?”.
4. Avoid loaded questions.
A loaded question in survey writing can force a respondent to answer a question without it reflecting their option or situation. For example, instead of asking “do you enjoy watching sports?”, yes or no. Ask “do you watch sports?” and then ask those who do watch sports, “what is your favorite sport to watch?”. The respondent might have never watched sports before and therefore not know the answer to the previous question. Asking the question in this way will provide much more accurate, detailed data which will be easier to analyze.
5. Refrain from incorporating double-barreled questions.
It is impossible to collect precise data from a double-barreled question. An example of a double-barreled question is asking if a concept is interesting and effective. This does not give respondents the option to give an answer to both questions. They may find the concept interesting but not effective but have no way of responding with the correct information.
6. Do not ask questions in absolute terms.
Absolute questions are questions that force a respondent to give an absolute answer. These questions are not flexible. Respondents cannot provide useful information if they answer an absolute. An example of an absolute question would be “Do you play sports? yes or no. With this question, someone who plays sports twice a year has to answer yes along with the people who play sports everyday. In order to get a more detailed answer and provide clearer data for the researcher, ask the respondent how many times a week/month they play sports.
Although these errors seem obvious, it is very common for them to appear in surveys. It is essential to keep these six common missteps in mind when writing your survey.
The main goal of every survey is to collect useful information that is both accurate and easy to analyze, however, if one of these mistakes makes its way into your survey it could bias or damage your data and make it impossible to interpret. It’s vital to your results to follow these rules. Just a little question bias could ruin the survey responses and turn your results into a nightmare. Don’t let it happen by following these easy steps.
Want to Learn More About Market Research? Here are some blog posts to check out!
- What Questions Should You Ask a Market Research Company
- Types Of Market Research Every Advertiser Should Know
- What is Advertising Research?
- Why Primary Research is Necessary When Launching a Brand
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It is a paradox few economists expected to see in the middle of the most significant period of economic disruption since the Second World War: a jobs boom. But then economists miss a lot of things.
Up and down the country, more and more vacancies keep appearing – stretching from a shortage of lorry drivers and manufacturing workers, to bartenders and waiters. Many of these opportunities are coming at a time when social restrictions remain and there are mutterings that the Indian (Delta) variant poses a threat of local lockdowns.
It is against this backdrop that a sea change is under way in the labour market. On Friday 21 May, over 18,297 jobs were posted to reed.co.uk – the highest daily number I can recall in years – taking the total number of vacancies on the site to well over 240,000. In fact in May we received more new jobs than in any month since February 2008.
Job opportunities are swelling in regions previously hit hard by the pandemic. London, for instance, experienced an 18 per cent increase in job numbers in May compared to April and had the largest volume of postings across all regions, with 57,100 jobs added.
This surge contrasts with last year’s reports of jobs receiving thousands of applicants and suggests that the labour market is shifting from a buyer’s to a seller’s market.
By this, I mean the tables have turned: skilled workers now hold all the cards and can demand a higher price which, in turn, will require businesses to work harder to secure talent.
One obvious way businesses can do this is by raising their wages – and the best way to do this is by increasing productivity so that they can pay people more. These will be the companies that win in the new economy.
Given the current economic climate, employers will be pleased to learn that there are many cost-effective ways they can find new hires and make themselves more attractive – whether that is finding an agency partner or going online.
Firms must employ good recruitment practices, such as giving applicants quick responses and detailed feedback, and including information about salaries, benefits and work perks in job postings. Equally employers must avoid bad recruitment practices, such as setting inordinate tasks and requiring substantial experience for entry-level roles. These are unacceptable in any jobs market.
The switch to a seller’s market is likely to last for a significant period and many companies will struggle to attract workers. Businesses will need as many boots on the ground as possible to take advantage of what is expected to be the fastest period of economic growth in living memory.
Companies must improve interview processes, think creatively about ways they can attract and retain top talent, and look further afield for alternative candidates. | https://inews.co.uk/opinion/comment/staff-shortages-put-jobseekers-in-the-driving-seat-as-thousands-of-vacancies-are-posted-online-1033680 |
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