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- This event has passed.
45th Annual Honolulu Intertribal Powwow
October 5 - October 6
Everyone is welcome to attend a Powwow. It is a wonderful way to learn more about Native American culture and tribal traditions. Above anything else, powwows are social events, a time to see old friends, make new acquaintances, listen, dance, and sing to the heartbeat of the drum, enjoy the taste of freshly prepared frybread, and especially to share our tribal heritage with the community. Don’t be afraid to ask questions and engage in conversation with vendors, dancers, singers, and other powwow participants. Many of our tribal elders in the community will sit around the arena circle and will have many stories to share and are full of knowledge of the “old ways.”
For those of you attending your first powwow, here are some rules and guidelines to
make it more enjoyable:
Be considerate. Some people do not wish to be photographed or video taped. Consider the privacy of the individual, and ask permission before you record them on film or tape. This includes spectators and crafts people as well as dancers and singers.
Be courteous. If you intend to use your photography for commercial purposes please inform the individual. Be sure to get a signed release and offer the subject a copy of your work or contact information.
Be polite. Do not block the view of other spectators and pay attention to the announcers references to Powwow Etiquette and protocol.
Be respectful. Do not enter the dance arena to film or photograph.
Show respect to the Elders, Dancers, and Drummers. Give them priority in line at restrooms, food line, etc. The drum represents the heartbeat of our people, please do not enter the drum tent/circle unless you are invited.
Chairs/benches placed around the dance arena are reserved for dancers. There is a reserved
tent for the elders to sit. Please feel free to bring your own chairs, towels, blankets, or mats to sit on.
Everyone wants to see, so be careful not to block the view of those behind you! | https://www.talkjive.org/event/45th-annual-honolulu-intertribal-powwow/ |
EP: This is a less technical adaptation of the original Hockey and Euclid guest post on WAR On Ice. The underlying math will be discussed briefly in the footnotes.
Spatial reasoning is an innate characteristic in humans. It allows us to intuit conclusions from imagery, which may be exploited by graphical representation of data.1For my money, Micah McCurdy belongs in a class of his own when it comes to hockey-related data viz. You can donate to his cause on Patreon. You’ve no doubt inadvertently benefited from this fact if you’ve ever gleaned information from a chart or visualization. Elements like proximity between points are more easily interpreted in this fashion than they are through the examination of numeric data. In many ways, this idea was the first building block of what would become a generalized method of computing statistical similarity between hockey players.
In two (and to a slightly lesser extent, three) dimensions, understanding and solving for proximity between points is a simple exercise. For all intents and purposes, the similarity that interests us is simply the inverse of the distance – something we’re taught how to calculate in basic trigonometry.2Pythagorean theorem Imagine plotting each NHL player-season by dimensions corresponding to their goal and assist rates. Neighbours clustering around a given point would represent that point’s (player’s) closest comparables in these two measures. Recall that similarity between data is inversely proportional to distance. Transitioning to Euclidean space allows us to generalize this approach for numbers of dimensions beyond the three we can visualize and interpret. We may now derive a standard similarity formula that functions in any number of dimensions.3Here, dimensions can be any numeric measure providing information about players.
The Similarity values may be interpreted as such: The Similarity between two players subtracted from 100 gives the percentage of the maximum allowable distance that is represented by the distance between the two positions occupied by the players. In other words, a 98% similarity between players would mean the distance between their positions in imaginary space is 2% of the largest possible distance that could exist between two points in the space bounded by observed values of each dimension. If you had plotted players according to G/60 and A/60 as described above, this maximum distance would be given by the distance between two corners of the plot.5Mathematically, this equates to each p1 – p0 term in the distance formula being equal to its denominator. The distance equation simplifies to the square root of the sum of all weights, thus the Similarity calculation gives 100 x (1 – 1) = 0.
By default, the Similarity Calculator returns only players of the same position. Because results are dependant on the selected weights, it’s important to be mindful of the conclusions you should or shouldn’t draw from them.
1. ↑ For my money, Micah McCurdy belongs in a class of his own when it comes to hockey-related data viz. You can donate to his cause on Patreon.
3. ↑ Here, dimensions can be any numeric measure providing information about players.
4. ↑ Where p0 and p1 are the origin and comparison points, respectively, i, …, n are the measures by which you are comparing and w are the corresponding weights.
5. ↑ Mathematically, this equates to each p1 – p0 term in the distance formula being equal to its denominator. The distance equation simplifies to the square root of the sum of all weights, thus the Similarity calculation gives 100 x (1 – 1) = 0.
This similarity scores calculator is bookmark-worthy and a great reference tool for any fan of analytics. | http://www.corsica.hockey/blog/2016/02/26/hockey-and-euclid/ |
Summary :
- Establish and maintain positive and productive relationships with internal resources and external customers.
- Provide outstanding customer service. Be responsive and timely in responding to questions, concerns, and requests.
- Serve as primary point-of-contact to the customer and cross-functional teams for day-to-day execution.
- Interpret and meet customer expectations and requirements to ensure outstanding customer satisfaction.
Location: US- Remote
Responsibilities:
- Responsible for overall project management through the life cycle (initiate, plan, execute, control, close).
- Create and manage project schedules and communicate schedule deadlines to internal and external groups.
- Manage customer requirements and documentation required to effectively manage program deliverables as assigned.
- Networks with all project stakeholders and resources (including customers, internal shared services groups, subcontractors, and vendors) to meet project goals.
- Ensures adherence to the quality management plan for all project deliverables.
- Identify changes to project scope or costs and work with the Program Manager to implement scope modification.
- Identify and track project risks and work with project stakeholders on risk mitigation plans.
- Identify and implement opportunities for process and quality improvements that promote cost reduction.
- Execute the tasks as defined in the project plan and schedule in order to meet customer deliverables.
- Prepare and present internal and external reports on program status, risks, and other program-related issues.
- Lead Customer and Internal Meetings, including status meetings, planning meetings, and lessons learned meetings.
- Capture project action items, assign owners, and manage closure.
- Support Program Manager with program invoicing and providing necessary documentation for invoicing.
- Identify process improvement initiatives in order to reduce cost while maintaining quality.
Qualifications:
- Bachelor’s Degree desired or commensurate experience.
- 5 years of experience in a Project Management role.
- PMP certification is preferred or demonstrates an understanding and application of Project Management Institute (PMI) principles.
- Ability to make decisions based upon limited information.
- Demonstrate ability to manage multiple, conflicting priorities, and work in a fast-paced, ever-changing environment.
- Significant experience with customer service
- A high sense of urgency and attention to detail are required.
- Effective verbal/written communication skills, strong listening, negotiation, and facilitation skills, and the ability to develop and deliver presentations.
- Experience with software development life cycle and case management preferred
- Knowledge of K12 student assessment preferred
- Some travel may be required.
Updated category job
As required by the Colorado Equal Pay Transparency Act, Pearson provides a reasonable range of minimum compensation for roles that may be hired in Colorado. Actual compensation is influenced by a wide array of factors including but not limited to skill set, level of experience, and specific office location. For the state of Colorado only, the range of starting pay for this role is $55,000 – $70,000. This position is eligible to participate in an annual incentive program, and information on the benefits offered is here. | https://freeonlinejobalert.com/work-from-home-indianapolis/ |
BACKGROUND OF THE INVENTION
0001 The present invention relates to unloader valves, and particularly to unloader valves used with positive displacement pumps. More particularly, the present invention relates to a flow-actuated unloader valve for a pressure washer system.
0002 Pressure washers provide a supply of high-pressure fluid for performing various tasks (e.g., paint and stain removal, drain cleaning, driveway cleaning, etc.). Usually the water is mixed with a cleaning solution such as soap, ammonia solution, bleach, or other chemicals.
0003 Pressure washers often include an engine that drives a high-pressure pump to supply the cleaning fluid. A trigger-actuated valve (i.e., spray gun) mounted to the discharge hose from the pump allows the user to remotely control the supply of high-pressure fluid. When the trigger is depressed, cleaning solution is discharged. When the trigger is released, the flow of fluid stops and the pump is disengaged, the engine is turned off, or the high-pressure fluid is bypassed to avoid causing damage to the pressure washer system. To that end, many pressure washers include unloader valves that bypass fluid back to the fluid reservoir when the fluid is not being discharged.
0004 Unloader valves, sometimes referred to as bypass valves or diverter valves, are used as a control mechanism for pressure washer systems. The unloader valve controls the pressure and the direction of flow within the system. Located between the outlet side of a pump and a discharge device (such as a spray gun), the unloader valve diverts fluid from the pump outlet back to the pump inlet through a bypass passage when the discharge passage becomes blocked (spray gun valve closed), thereby reducing pressure within the pump. When the discharge passage is unobstructed (spray gun valve open), the unloader valve redirects fluid back to the discharge device and allows the pump pressure to rise back to its' normal operating pressure.
0005 Some pressure washer systems include the ability to inject cleaning solution directly into the discharge stream exiting the high-pressure side of the pump. To add cleaning solution, the user premixes the solution with the water or the solution is drawn into the pressure stream by vacuum with the use of a venturi, this method is commonly referred to as chemical injection. Chemical injection typically requires a separate apparatus adding cost and complexity to the pressure washer. Of the known pressure washer systems to have chemical injection, all require the use of additional components to perform this task. Such additional components may include a separate venturi, housings, o-rings, etc.
0006 Summary of the Preferred Embodiments
0007 The invention provides an unloader valve including a body that engages the pump housing to receive the high-pressure flow from the pump. The preferred valve body design consists of an inlet, an outlet, a bypass passage and an inlet passage for chemical injection. Within the valve body is a shuttle-valve that defines two primary chambers. These two chambers are in fluid communication with one another through a small port (venturi) in the shuttle-valve. The shuttle-valve is movable between a bypass position and a spray position. The shuttle-valve is biased in the bypass position by a spring on the discharge side of the shuttle valve.
0008 Yet another feature of the invention is the cleaning solution inlet. The cleaning solution inlet allows for the admission of a cleaning solution (e.g., soap, ammonia, detergent, bleach, etc.) into the stream of high-pressure water. Flow exiting the high-pressure outlet first passes through a venturi disposed within the movable shuttle valve. The throat area of the venturi is in fluid communication with the cleaning solution inlet. The high-velocity flow through the venturi produces a low-pressure in the throat, thereby drawing the cleaning solution into the venturi.
0009 Combining the cleaning solution inlet and the unloader valve into a single housing greatly reduces the number of parts used. The reduction in parts reduces the cost and complexity of the unloader valve and cleaning fluid inlet.
BRIEF DESCRIPTION OF THE DRAWINGS
0010 The detailed description particularly refers to the accompanying figures in which:
0011FIG. 1 is a perspective view of a pressure washer including an unloader valve;
0012FIG. 2 is an exploded cross-sectional view of the unloader valve of FIG. 1;
0013FIG. 3 is a cross-sectional view of the unloader valve of FIG. 1;
0014FIG. 4 is a cross-sectional view of the unloader valve of FIG. 1 in a bypass position;
0015FIG. 5 is a cross-sectional view of the unloader valve of FIG. 1 in a spray position; and
0016FIG. 6 is a perspective view of a pressure washer.
DETAILED DESCRIPTION OF THE DRAWINGS
0017 Most unloader valves have specific operating ranges, limiting their applications and affecting their performance as conditions change within the high-pressure washer system. The limitation to applications costs manufactures because it requires different design variations, additional parts that need to be inventoried, additional complexity to the assembly process, and so on. The affects in the unloader valve performance due to variations in the system can be costly to the manufacturer and a nuisance to the user. The additional cost to the manufacturer manifests itself on many different levels. For example, the requirement for multiple adjustments during factory setup (back and forth between the engine speed and the unloader pressure adjustment), higher scrap rates, warranty returns, etc. all increase manufacturing costs. The nuisance to the user would include pulsation in the pump pressure, loss of pressure, or large delays in spray pressure when triggering the spray gun.
0018 Most conventional unloader valves are designed with a high rate spring that will allow the opening of a valve only at some preset pressure. In most cases, this preset pressure only occurs in the form of a high-pressure spike when the spray gun valve is closed. The value of this high-pressure spike is usually well in excess of what the pump can maintain for extended periods. With most of these designs, this high-pressure value must be maintained (or trapped) within the discharge line and allowed communication against the high-rate spring in order to keep the bypass open. If the trapped linepressure is lowered due to leakage, hose expansion, etc., then the high-rate unloader spring will close the bypass valve, thereby allowing pressure to rise, even though the spray gun valve is still closed. This unwanted increase in pressure during the bypass state, usually results in pressure pulsations within the pump, engine stalls, or even severe pump or engine damage. For these reasons, it would be desirable to have an unloader system that would function in a wide range of operating conditions, does not require large pressure spikes to overcome heavy spring forces, and does not require factory adjustments.
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0019 With reference to FIG. 1, a pressure washer includes a frame , a motor or engine , a pump , various hoses and fittings , an unloader valve , and a spray gun (shown in FIG. 6). The engine mounts to the frame and drives the pump . While FIG. 1 illustrates an internal combustion engine, other types of engines are possible (e.g., diesel, natural gas powered, or electric motors).
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0020 The frame is supported for movement by a plurality of wheels and provides support for the various components. As such, the frame is generally manufactured from a structural material (e.g., tubing, channels, or rods made of steel, aluminum, other metals, composites and the like). The frame includes a handle portion that extends above the pressure washer components. The handle provides a convenient point for the user to grasp the pressure washer for movement. In addition, controls (e.g., start/stop buttons, keyholes, etc.) and indicators (e.g., lights, gages, or dials) are often positioned on or near the handle portion to allow the user easy access.
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0021 Preferred constructions of the pressure washer include positive displacement pumps (e.g., gear-type pumps, reciprocating pumps, screw pumps etc.). However, other constructions employ other types of pumps such as centrifugal and rotary pumps. The pump receives a flow of fluid at an inlet and discharges a high-pressure flow at an outlet . A fluid reservoir supported by the frame provides fluid to the pump inlet. Alternatively, an external source provides fluid to the pump . Typically, the fluid used is water however, other fluids can be used (e.g., soap-water solution, ammonia solution, etc.). In some constructions, an operator controls the discharge pressure of the pump via a pressure control valve, or by varying the rotating speed of the engine . The user's control of the pressure can be direct (e.g., moving a throttle lever) or indirect (e.g., turning a knob to adjust a pressure switch that in turn controls a relief valve).
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0022 As illustrated in FIG. 2, the unloader valve includes a housing that connects directly to the pump outlet (FIG. 1). In preferred constructions, the housing and the pump outlet include threads sized to engage one another. In other constructions, other attachment methods are used (e.g., welding, flange-mounted, or integrated with the pump housing). In still other constructions, the unloader valve is positioned remote from the pump .
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0023 Referring again to FIG. 2, an exploded view of the unloader valve is shown. The unloader valve includes the housing , a movable shuttle valve , a biasing member , and a chemical injection inlet barb .
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0024 The housing includes a central chamber that extends from an open inlet end to an open outlet end . The chamber includes several cylindrical sections having walls that are substantially parallel to the longitudinal axis - of the housing . In addition, the housing includes a shoulder having a wall that is substantially perpendicular to the longitudinal axis -. The housing also includes an angled wall that defines a frustoconical region.
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0025 A series of radial bores extend through the housing near the threaded portion and provide a flow path out of the housing . In addition, a large threaded bore extends partially through the housing and is in fluid communication with the interior of the housing via a smaller bore .
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0026 As shown in FIG. 3, the housing threads into the pump such that the radial bores align with a bypass return hole . A reducer-pilot bushing is sandwiched between the housing and the pump to provide a seal between the pump outlet and the threads . Alternative constructions combine the reducer-pilot bushing and the unloader valve housing .
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0027 Referring again to FIG. 2, the movable shuttle valve includes a bypass member and an operating member . The bypass member defines an internal chamber open at the inlet end of the valve housing to receive the flow of high-pressure fluid from the pump outlet . A plurality of radial bores extend through the bypass member to provide a path for the fluid out of the bypass member and into a bypass chamber (shown in FIG. 3). The bypass chamber is defined by the housing and the bypass member , and is in fluid communication with the radial holes of the valve housing .
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0028 The outer surface of the bypass member includes an O-ring groove , a spring land , and a threaded portion . A first O-ring fits within the O-ring groove and provides a seal between the housing and the bypass member of the movable shuttle valve near the inlet end . In the construction of FIG. 2, the first O-ring provides a seal between the bypass member and the reducer-pilot bushing .
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0029 The threads of the threaded portion are sized to engage an opposite set of threads on the operating member of the shuttle valve . In the construction of FIGS. 2 and 3, the male threads are located on the bypass member and the female threads are on the operating member . Alternative constructions reverse the location of the male and female threads or use other attachment methods (e.g., welding, brazing, soldering, or quick-connects).
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0030 The operating member includes a threaded portion , a plurality of radial inlets , an axial outlet , an O-ring groove , and two sliding bearing grooves . As discussed above, the threaded portion accommodates the threaded portion of the bypass member , thereby allowing the bypass member and the operating member to rigidly connect to one another.
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0031 The O-ring groove and the two sliding bearing grooves are located on an outer surface of the operating member and extend completely around. The O-ring groove supports a second O-ring near the threaded portion of the operating member . The function of this O-ring will be discussed below with regard to FIGS. -. The sliding bearing grooves each support a sliding bearing . The sliding bearings engage the inner cylindrical surface of the housing and maintain the shuttle valve in the proper alignment, while minimizing friction. Preferred constructions use plastic sliding bearings . However, other materials are available and will function as sliding bearings (e.g., brass, bronze, steel, composites, ceramics, or rubber).
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0032 The radial inlets direct fluid into an internal chamber defined by the operating member . The internal chamber extends axially along the centerline of the operating member and includes a venturi . The venturi is integrally formed with the operating member . In other constructions, a separate venturi is fixed within the flow path of the operating member . The venturi includes an inlet and an outlet. Between the inlet and the outlet is a throat having a smaller flow area than the inlet and the outlet. A plurality of radial bores connect the throat of the venturi to an injection chamber disposed between the sliding bearings and between the operating member and the unloader valve housing . The reduced flow area of the throat accelerates the flow and reduces its pressure to aid in the introduction of fluid from the injection chamber .
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0033 The chemical injection inlet barb connects to the housing adjacent the injection chamber and includes a valve body with a seat, a ball , and a spring . The valve body threads into the unloader valve body , thereby trapping the ball and the spring within a portion of the injection chamber . The ball rests on the seat and is biased in the closed position by the spring . The chemical injection inlet barb is in fluid communication with a fluid or other substance (e.g., soap, ammonia solution, or other chemicals) to be injected into the injection chamber and into the high-pressure stream.
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0034FIG. 3 shows the unloader valve of the invention in its assembled condition. The operating member of the movable shuttle valve is inserted into the unloader valve housing through the outlet opening . The operating member slides toward the inlet until the second O-ring abuts the angled surface within the housing . A biasing member, in this construction a compression spring , slides over the bypass member of the shuttle valve and engages the spring land . The spring and bypass member are inserted into the unloader housing through the inlet opening . The spring engages the shoulder within the housing and must be compressed to insert the bypass member further. The bypass member and the operating member engage one another and are threaded together.
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0035 The chemical injection inlet barb also threads into the housing to complete the assembly of the unloader valve .
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0036FIGS. 4 and 5 illustrate the unloader valve in two different modes of operation. FIG. 4 illustrates the unloader valve in the bypass position and FIG. 5 illustrates the valve in its spray position.
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0037 Referring to FIG. 4, high-pressure flow exits the pump and enters the unloader valve . The flow passes through the bypass member and out the radial holes (shown in FIG. 3). The flow enters the bypass chamber defined between the first and second O-rings , and the bypass member and the housing . The second O-ring remains sealed against the angled surface of the housing . High-pressure fluid on the outlet side of the operating member , along with the force produced by the spring , maintain the seal force on the second O-ring . High-pressure flow is unable to pass into the operating member . Instead, the high-pressure flow passes over the outer surface of the bypass member and exits the unloader valve through the bypass opening . In preferred constructions, the bypass opening is in fluid communication with the pump inlet or reservoir. The bypassed fluid thus returns to the pump to be pumped through the unloader valve again.
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0038FIG. 5 illustrates the unloader valve in the spray position. As described with respect to FIG. 4, the flow enters the bypass member of the movable shuttle valve and passes through the radial holes . However, the movable shuttle valve is shifted toward the outlet end of the unloader valve when in the spray position. The shift allows an angled surface of the outer surface of the bypass member to contact or rest near the corner of the shoulder supporting the spring . The position of the angled surface substantially reduces the flow area to the bypass outlet and effectively closes off the path. However, the shift has moved the second O-ring off the angled surface it rested on during bypass operation, thereby providing a flow path to the outer surface of the operating member . The first sliding bearing provides a seal that forces the high-pressure fluid into the second set of radial holes located in the operating member . The fluid passes through the radial holes and into the central flow chamber of the operating member . The flow passes through the venturi disposed in the central chamber and out the outlet side of the unloader valve . The exiting flow then passes through a pipe, tube, or hose to a spray gun for use.
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0039 The flow passing through the venturi accelerates as it passes through the throat . The local acceleration and relatively high flow velocity produce a local low-pressure region. The pressure is low enough to open the chemical injection inlet barb and draw in the fluid or other material.
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0040 Overcoming or releasing the biasing force allows the unloader valve to transition from the bypass position to the spray position. In preferred constructions, a control mechanism such as a user controlled valve in the spray gun releases the pressure on the outlet side of the operating member . Once released, the pressure on the outer surface of the bypass member and within the bypass member is sufficient to overcome the spring biasing force and shift the movable shuttle valve into the spray position. In the construction of FIG. 6, the spray gun includes a trigger that directly or indirectly opens a valve. When the user depresses the trigger, the unloader valve shifts to the spray position and high-pressure fluid is directed out the spray gun . When the user releases the trigger the pressure on the outlet side of the operating member increases and equalizes the pressure on the bypass member , thereby allowing the spring to bias the movable shuttle valve into the bypass position.
0041 In the start-up phase, the biasing spring keeps the shuttle-valve in the bypass position, thereby creating an opening to the bypass passage. At this point there is no flow through the venturi of the shuttle valve, all fluid is diverted to the bypass passage. As a result, there is no significant pressure increase to cause resistance to starting or loading of the engine.
0042 When a user wishes to discharge high-pressure fluid from the pump, a discharge valve is opened (spray gun is triggered). This allows for the flow of fluid through the venturi of the shuttle-valve. The flow of fluid across the venturi creates a pressure differential between the two chambers. The resultant force between the two chambers overcomes the spring force, moving the shuttle valve into the spray position. When the shuttle valve is in this position, the bypass passage is closed, thereby allowing the pump pressure to rise to a suitable level for the operator to perform the desired tasks.
0043 When the user wishes to disengage the pump, he/she simply closes the discharge valve (releases the spray gun trigger) stopping the flow of fluid across the shuttle-valve venturi. When the flow across the venturi ceases, the pressure between the two chambers begins to equalize. As the two chamber pressure values near equilibrium, the biasing spring becomes the resultant force and moves the shuttle-valve back to the bypass position. With the shuttle-valve in the bypass position, an opening is created that allows the flow of fluid to be diverted back to the bypass port.
0044 This method for transitioning the unloader system between the bypass mode and the spray mode is commonly referred to as flow-actuated. The flow-actuated method is considered to be more desirable than pressure activated unloader systems for several reasons. Most conventional unloader systems use high-rate unloader springs that require high pressure-spikes to activate, as previously described. In contrast, the present invention monitors the flow of fluid through pressure differentials and does not require such high pressure-spikes to function. This provides smoother transitions from one mode to the next. A reduction in water hammering is seen, reducing the wear and tear of the pressure washer system. If the discharge line were to become gradually obstructed (i.e. clogged nozzle, pinched hose, etc.), the present invention would transition to the bypass mode as the flow diminished, unlike conventional unloader valves.
0045 Another desirable benefit to using the flow-actuated method is the versatility that is inherent to the design. All that is required for operation is the flow of fluid, not specific pressure values that can limit applications and/or require unnecessary factory adjustments. Large variations in the motor speed are permitted, without hindering the function of the present invention.
0046 Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims. | |
Research has shown that certain foods can lower blood pressure. Combining these foods in the diet may lead to long-term health benefits.
Medications, dietary changes, and other lifestyle modifications can reduce high blood pressure, or hypertension, while lowering the likelihood of developing associated conditions. High blood pressure increases a person’s risk of heart disease, stroke, and kidney disease.
Types of food that may help include:
- fruits, such as kiwi and oranges
- vegetables, for instance, green leafy vegetables and beets
- nuts, for example, pistachios and walnuts
- oily fish, such as mackerel
- spices, such as cinnamon
In this article, we discuss foods that can help reduce high blood pressure, and provide scientific evidence.
A note about sex and gender
Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.
Many researchers have found that certain foods can lower high blood pressure. We look at some foods that may help and how to incorporate them into the diet.
In general, the United States Department of Agriculture (USDA) considers a serving to be:
- 1 cup of cooked or raw vegetables or fruit
- 1 cup of 100% fruit juice
- 2 cups of raw leafy salad greens
- half a cup of dried fruit
For most ages, the USDA recommends consuming around 2 cups of fruit per day and 3 cups of vegetables per day, although this varies slightly according to age and sex.
1. Berries
Blueberries and strawberries contain antioxidant compounds called anthocyanins, a type of flavonoid.
In one older study, the researchers looked at data for over 34,000 people with hypertension over 14 years. Those with the highest intake of anthocyanins — mainly from blueberries and strawberries — had an
However, some
To enjoy berries:
- eat them as a snack or sweet treat after meals
- add them to smoothies
- sprinkle them on oatmeal for breakfast
A serving of blueberries is around 1 cup of fresh or frozen blueberries or half a cup of dried blueberries. A serving of strawberries is around 7 strawberries.
Which other foods are rich in antioxidants?
2. Bananas
Bananas contain potassium, which can help manage hypertension. One medium-sized banana contains around
According to the
The Office of Dietary Supplements advises that males aim to consume
Other potassium-rich foods include:
People with kidney disease should consult a doctor before increasing their intake of potassium, as too much can be harmful.
A serving would be 1 large banana, 1 cup of sliced banana, or two-thirds of a cup of mashed banana.
3. Beets
Drinking beet juice may reduce blood pressure in the short and long term, because it contains dietary nitrate.
A
Tips for use include:
- drinking 1 glass of beet juice per day
- adding beets to salads
- preparing beets as a side dish
A serving of beet is around 1 cup, which is around 2 small beets or 1 large one.
4. Dark chocolate
Cacao, an ingredient in dark chocolate, contains flavonoids, an antioxidant. Flavonoids may help reduce blood pressure, according to the
However, it notes that a person may not be able to consume enough flavonoids in dark chocolate for it to have significant benefits.
The AHA says that a small amount of chocolate from time to time can be part of a balanced diet. It advises, however, that people eat it because they enjoy it, not for health reasons.
5. Kiwis
A daily serving of kiwi can help manage mildly high blood pressure, a
People who ate 3 kiwis per day for 8 weeks saw a more significant reduction in systolic and diastolic blood pressure than those who ate 1 apple per day for the same period. The study authors note that this may be due to the bioactive substances in kiwis.
Kiwis are also rich in vitamin C. In an
Kiwis are easy to add to lunches or smoothies. One cup of kiwi, or 2–3 kiwifruits, makes up 1 serving.
Which other foods contain vitamin C?
6. Watermelon
Watermelon contains an amino acid called citrulline.
The body converts citrulline to arginine, and this helps the body produce nitric oxide, a gas that relaxes blood vessels and encourages flexibility in arteries. These effects aid the flow of blood, which can lower high blood pressure.
In one older study, adults with obesity and mild or prehypertension took watermelon extract containing 6 grams (g) of L-citrulline/L-arginine.
After 6 weeks, the participants saw a reduction in blood pressure in the ankles and brachial arteries. The brachial artery is the main artery in the upper arm.
In a small
People can consume watermelon:
- as juice
- in salads, including fruit salads
- in smoothies
- in a chilled watermelon soup
One serving of watermelon is 1 cup of chopped fruit or 1 slice of around 2 inches.
7. Oats
Oats contain a type of fiber called beta-glucan, which
A
Ways of eating oats include:
- having a bowl of oatmeal for breakfast
- using rolled oats instead of breadcrumbs to give texture to burger patties
- sprinkling them on yogurt desserts
8. Leafy green vegetables
Leafy green vegetables are rich in nitrates, which help manage blood pressure.
Some
Examples of leafy greens include:
- cabbage
- collard greens
- kale
- mustard greens
- spinach
- Swiss chard
To consume a daily dose of green vegetables, a person can:
- stir spinach into curries and stews
- saute Swiss chard with garlic as a side dish
- bake a batch of kale chips
A serving of spinach is 2 cups of fresh leaves. A serving of raw cabbage is 1 cup.
9. Garlic
Garlic has antibiotic and antifungal properties, many of which may be due to its main active ingredient, allicin.
A
- blood pressure
- arterial stiffness
- cholesterol
Garlic can enhance the flavor of many savory meals, including stir-fries, soups, and omelets. It can also be an alternative to salt as a flavoring.
10. Fermented foods
Fermented foods are rich in probiotics, which are beneficial bacteria that
In
Sodium is a risk factor for high blood pressure, and experts advise people to limit their salt intake. However, a 2017 study did not find that eating salt-fermented vegetables increased the risk of high blood pressure, despite the high sodium content.
The effects of probiotics on blood pressure appeared more beneficial when the participants consumed:
- multiple species of probiotic bacteria
- probiotics regularly for more than 8 weeks
- at least 100 billion colony-forming units per day
Fermented foods to add to the diet include:
- kimchi
- kombucha
- apple cider vinegar
- miso
- tempeh
Probiotic supplements are another option.
11. Lentils and other pulses
Lentils provide protein and fiber, and
The authors of an
A
People can use lentils in many ways, including:
- as an alternative to minced beef
- adding bulk to salads
- as a base for stews and soups
12. Natural yogurt
Yogurt is fermented dairy food.
A
The participants with high blood pressure who consumed more yogurt had lower systolic blood pressure and lower arterial pressure than those who did not.
To enjoy unsweetened yogurt:
- add 1 spoonful to a plate of stew or curry
- mix with chopped cucumber, mint, and garlic as a side dish
- use it instead of cream on fruit and desserts
- spoon it onto a combination of oatmeal, nuts, and dried fruit for breakfast
13. Pomegranates
Pomegranates contain antioxidants and other ingredients that
An
A
People can consume pomegranates whole or as juice. When buying prepackaged pomegranate juice, check to ensure that there is no added sugar.
14. Cinnamon
Cinnamon may help reduce blood pressure, according to a
To incorporate cinnamon into the diet, a person can:
- add it to oatmeal as an alternative to sugar
- sprinkle it on freshly chopped fruit
- add it to smoothies
15. Nuts
Several studies have found that eating nuts of various types can help manage hypertension.
A
Opt for unsalted nuts and:
- snack on them plain
- add them to salads
- blend them into pestos
- use them in main dishes, such as nut roast
People should not consume nuts if they have a nut allergy.
16. Citrus fruits
Citrus fruits contain hesperidin, an antioxidant that may benefit heart health.
In a
The results indicate that regularly consuming orange juice can help lower systolic blood pressure and that hesperidin contributes to this effect.
People can consume citrus fruits:
- as drinks, for example, by making orange juice or squeezing lemon into water
- whole or in fruit salads, in the case of oranges and grapefruit
- as lemon juice, squeezed on salads for flavor instead of salt
17. Oily fish
The AHA recommends consuming
Examples of oily fish are:
- anchovies
- sardines
- mackerel
- albacore tuna
Some fish contain mercury, and people should check the latest
18. Tomato extract
Tomato contains lycopene, an antioxidant that may be beneficial for heart health.
A
Other
While some foods may relieve hypertension, others can increase the risk of the condition.
Salt
Studies show that a modest decrease in salt intake over
The USDA recommends limiting sodium intake to a maximum of
Caffeine
Results of a
In a
Alcohol
Regular consumption of alcohol can significantly increase the risk of high blood pressure. In females, even moderate consumption can have this impact. There is no evidence that a low to moderate intake has any benefits for heart disease or hypertension, according to a
The
Processed foods
Processed foods often contain added salt and harmful fats. A
Here, learn about 50 foods to avoid if a person has high blood pressure.
As well as dietary measures, the
- Exercise regularly.
- Learn some strategies for managing stress.
- Avoid or quit smoking.
- Reach or maintain a moderate body weight.
- Work together with a doctor, including taking any medications they recommend.
Here are some questions people often ask about lowering blood pressure.
How can I lower my blood pressure immediately?
There is no way to lower blood pressure quickly at home. A person should follow a plan of diet, exercise, and possibly medication to lower their blood pressure over time.
If blood pressure is over
Can drinking water lower blood pressure?
Some
When should I contact a doctor about high blood pressure?
Optimal blood pressure is up to
Dietary and lifestyle choices can help manage high blood pressure.
A diet that focuses on fruits, vegetables, oats, nuts, lentils, herbs, and spices can be beneficial. In contrast, salt, alcohol, and processed foods may worsen hypertension.
A doctor can help a person make a plan that involves exercise, food choices, and other measures to manage high blood pressure and reduce the risk of cardiovascular disease and other health issues. | https://www.medicalnewstoday.com/articles/322284?utm_source=ReadNext |
Reviews of "The Path of the Priestess"
Sacred Mysteries Productions presents 2012: The Odyssey. Written and Directed by Sharron Rose. Produced by Jay Weidner. Featuring Jose Arguelles, Gregg Braden, John Major Jenkins, Rick Levine, Geoff Stray, Moira Timms, Alberto Villoldo, Jay Weidner, the Incan Elders and others. Armageddon is not what it used to be.
What lies ahead for the human race? Will we reach the destiny that awaits us? In the film 2012 The Odyssey, author Sharron Rose went on a quest to understand the many prophecies around the year 2012. In this sequel to that film, she travels far beyond the world of 2012.
During this fascinating expedition into the nature of time itself, Ms. Rose speaks to many of the world’s experts on mythology, alchemy, astrology, anthropology and ancient history; Jose Arguelles, Gregg Braden, Riane Eisler, William Henry, Jean Houston, John Major Jenkins, Rick Levine, Dennis McKenna, Terence McKenna, Daniel Pinchbeck, Geoff Stray, Whitley Strieber, Alberto Villoldo and Jay Weidner. They discuss topics such as the shift of the ages, the galactic alignment, global warming, the pervasive role of the media in our lives, the secret place of refuge, the mystic work of Benjamin Franklin, renewal of the American spirit and the transformation of humanity.
Journey with Ms. Rose beyond the Georgia Guidestones, Denver Airport, Cross of Hendaye and Mayan Calendar to the Sacred Valley of Peru where we sit in ceremony with the powerful Shaman/healers of the Q’ero people and listen to their powerful prophecies for the future of humankind.
While firmly based in a rich perspective on our past history, and a new understanding of the nature of the times we live in, Timewave 2013 offers a clear, yet positive vision of what is to come.
In this elegant and enlightening presentation, award winning author, educator and performing artist Sharron Rose introduces the feminine – based Yoga of Light, an ancient science and spiritual practice of physical and spiritual revitalization. Rooted in her extensive research and first-hand experience in women’s mysteries and the mystic arts of Tantra and Alchemy, Ms. Rose introduces a system of yogic training based upon the unique dynamics of the female energy field. This consists of meditations for relaxation and stress reduction, visualizations for cleansing, restoring and protecting the physical body and luminous energy field that surrounds it, mudras (sacred gestures) designed to depict the flow of subtle energy through the luminous field, and exercises to enhance visionary capacity and align women with the most powerful and profound feminine role model – the Great Goddess. Segments include; Yoga of Light, Cleansing the Luminous Body, Igniting the Inner Fire, Awakening the Serpent Power, Opening the Heart and Healing the Luminous Body.
A guide for personal exploration of the path of the Divine Feminine and the spiritual power of women, this book is an excellent compendium to the Awakening the Divine Feminine video series.
The Path of the Priestess takes readers on a compelling journey deep into the heart of the feminine experience, presenting a rare glimpse of the essential and significant role of women as caretakers of the psychic-energetic-emotional landscape of society. It is based upon the author's years of first-hand experience in the ancient arts of Tantra, Dzogchen, Indian and Egyptian Temple Dance and Healing, as well as her research into the feminine principle in the mystic teachings of the Alchemists, Hebrew Kabbalists and Christian Gnostics.
Through its mythic and historic tales, thought-provoking analysis of contemporary society's conditioning of women, descriptions of sacred ritual practices and teachings on the Goddess traditions, The Path of the Priestess provides contemporary women with the means to enter this time-honored path. In keeping with the experientially based teaching methods of these traditions, it also offers exercises and visualizations designed to align them with the powerful, sensuous and loving energies of the most profound feminine role model that shaped and preserved culture and society - the Great Goddess.
Reviews for "The Path of the Priestess"
"An inspiring read. Sharron Rose takes us along on her spiritual journey, unveiling at every turn the presence of the Divine Feminine that has been hidden in this age of spiritual materialism from which we are beginning to awaken."
"From the moment I read the first words of the preface, I knew that 'The Path of the Priestess' was totally 'on the beam'. The book provides both eloquent insights into the nature of Goddess energyand ways for the reader to realize it for themselves. As I feel that Goddess Consciousness is the evolutionary path of choice for the planet, I send Sharron my heartfelt appreciation and give the book my highest endorsement".
Sharron Rose, MA.Ed, is a filmmaker, teacher, writer, choreographer and Fulbright Senior Research Scholar in World Mythology, Religion and the Sacred Arts of Dance, Music and Theatre. She is the writer/director of the feature length documentary 2012 The Odyssey, author of the award winning book, The Path of the Priestess; A Guidebook for Awakening the Divine Feminine (Inner Traditions), creator of the DVD Yoga of Light and producer of the Sacred Mysteries DVD Collection. Read more.. | http://www.sharronrose.com/Home.html |
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---
abstract: 'We study a Hamiltonian system of type describing a charged particle resonant interaction with an electromagnetic wave. We consider an ensemble of particles that repeatedly pass through the resonance with the wave, and study evolution of the distribution function due to multiple scatterings on the resonance and trappings (captures) into the resonance. We derive the corresponding kinetic equation. Particular cases of this problem has been studied in our recent papers [@ANVM16; @ANVM17].'
author:
- 'A. V. Artemyev'
- 'A. I. Neishtadt'
- 'A. A. Vasiliev'
- 'D. Mourenas'
title: 'Kinetic equation for systems with resonant captures and scatterings.'
---
Introduction
============
Resonant phenomena are a key part in long-term evolution of numerous systems in plasma physics, hydrodynamics, celestial mechanics, etc. The phenomena of scattering on a resonance and capture (trapping) into a resonance were described in details in [@Neishtadt75; @Neishtadt99] (see also [@bookAKN06; @NV06]), and all the characteristics of a single passage through a resonance were obtained. These results were applied to studies of the resonant phenomena in various problems in physics; among recent studies we just mention papers [@Itin00; @Vainchtein04:prl; @Neishtadt11:mmj; @Vasiliev11; @Artemyev10:chaos; @Artemyev15:pre]. However, in physical systems one has usually to deal with an ensemble of particles (phase trajectories), which pass repeatedly through the resonance during long time intervals. These multiple resonant interactions affect the distribution function of the ensemble. Thus a crucial issue is to implement the properties of individual resonant interactions into a kinetic description of evolution of the distribution function.
A major peculiarity on this way is that captures into resonances provide fast and large-distance transport in the phase space, which cannot be described with differential operators in the kinetic equation. In the papers [@Shklyar81; @Artemyev14:grl:fast_transport; @Omura15], it was proposed to introduce integral operators describing this kind of transport. This approach, however, did not take into account kinetic balance between the captures and the scattering. Namely, while rare captures result in strong variation (say, growth) of energy of a small part of particles (phase trajectories), scatterings produce small energy variation in the opposite direction (decrease) of a large sub-ensemble. Therefore, to include these phenomena into the kinetic equation, one should find and implement the relationship between the corresponding kinetic coefficients. This approach was first proposed in [@ANVM16] in the simplest case of a Hamiltonian system with one and a half d.o.f., and in [@ANVM17] for a more realistic system with two d.o.f. In these papers, we have introduced a Fokker-Planck kinetic equation describing evolution of an ensemble of particles in a system where repeated scatterings on resonances and captures into resonances (followed by escapes from the resonances) take place. Our approach is based on the fact that one can introduce probability of capture into a resonance, and that this probability turns out to be interconnected with the velocity of the drift in the phase space due to scatterings on the resonance.
In the present work we derive the kinetic equation in a general case when the time period between successive passages through the resonance depends on the particle energy. In Section 2, we briefly outline the main approaches and results concerning an individual resonance crossing. In Section 3, we use these results to construct the kinetic equation describing the long-term evolution of the distribution function in a system with multiple resonant captures and scatterings. Note that in [@ANVM17] the similar equation was obtained with smaller terms omitted. In the present paper, these terms are taken into account allowing to represent the kinetic equation in a more elegant form.
Resonant phenomena in slow-fast Hamiltonian systems
===================================================
Consider a Hamiltonian system with Hamiltonian H = H\_0(p,q) + A(p,q)(kq-t), \[2.1\] where $\eps$ is a small parameter and $(p,q)$ are canonically conjugate variables. Such Hamiltonians naturally appear in problems of motion of a charged particle in a harmonic electromagnetic wave and a background magnetic field. This is a Hamiltonian system with 1$\frac12$ degrees of freedom. Introduce $t$ as a new canonical coordinate $u$, and $U$ as the canonically conjugate momentum. The Hamiltonian takes the form $$H = U + H_0(p,q) + \eps A(p,q)\sin(kq-\om u).$$ Now we introduce the phase of the wave as an independent variable $\ffi = q- \om u/k$. To do this, we make a canonical transformation $(p,q,U,u) \mapsto (\hat p, \hat q, I, \ffi)$ using generating function $$W = I(q-\frac{\om}{k}u) + \hat p q + \hat U u$$ Omitting constant $\hat U$ and omitting hats over $p$ and $q$, we obtain a 2 degrees of freedom Hamiltonian (we keep the same notations for the functions $H_0$ and $A$): H = -I + H\_0(p,q,I) + A(p,q,I)(k) \[2.2\] Now we rescale the variables introducing $\bar \ffi = k\ffi$. In order to keep the symplectic structure, we also rescale time introducing $\bar t = kt$ and consider $(p,kq)$ as a pair of canonically conjugate variables. We assume that $k^{-1} = \eps$. Omitting the bars we obtain the Hamiltonian in the new variables: H = H\_0(p,q,I) - v\_I +A(p,q,I) , \[2.3\] where we have used the notation $v_{\phi} = \om/k$. One can see from (\[2.3\]) that with the accuracy of order $\sim\eps$ the system stays on the energy level $H_0(p,q,I) - v_{\phi}I =\const$; thus, we obtain the following relation between the particle energy $h = H_0$ and the value of $I$: h - v\_I = . \[2.40\]
In Hamiltonian (\[2.3\]), the pairs of conjugate variables are $(p,\eps^{-1}q)$ and $(I,\ffi)$. The equations of motion in the main approximation are p &=& -\
q &=& \[2.30\]\
I &=& -A\
&=& -v\_ . Thus, in this system variable $\ffi$ is a fast phase, and the other variables are slow. Far from the resonance $\dot \ffi = 0$ the equations of motion can be averaged over the fast phase. Thus we obtain the averaged system: p = -, q = , I = 0 \[2.4\] Variable $I$ is the integral of the averaged system (\[2.4\]) and hence is an adiabatic invariant of the exact system (\[2.3\]) (see, e.g., [@bookAKN06]). Far from the resonance, it is preserved with a good accuracy along phase trajectories of (\[2.3\]).
We assume that the slow motion on the $(p,q)$-plane in the averaged system (\[2.4\]) is periodic. The area bounded by a trajectory of this averaged motion can be considered as a function of the energy $H_0=h$ or of the corresponding value of $I$ (see (\[2.40\])). The condition of resonance ${\pt H_0}/{\pt I}=0$ defines a curve on the $(p,q)$-plane (the resonant curve). In a general situation, trajectories of the averaged system cross the resonant curve.
In a small vicinity of the resonance, the averaging of equations (\[2.30\]) does not work properly, and here we apply the standard approach developed in [@Neishtadt99] (see also, e.g., [@bookAKN06; @NV06]). We expand the Hamiltonian $H$ into series near the resonant value of $I=I_R$, where $I_R = I_R(p,q)$ is found from the equation ${\pt H_0}/{\pt I}=v_{\phi}$. Thus we obtain Hamiltonian H = (p,q) + 12 g(p,q)(I-I\_R)\^2 + A(p,q,I\_R), \[2.5\] where $\Lambda = H_0(p,q,I_R)$ and $g = \left.\pt^2 H_0/\pt I^2 \right|_{I=I_R}$ and smaller terms are omitted. Introduce new canonical momentum $K = I-I_R$ with the generating function $W=\bar p \eps^{-1}q + (K+I_R)\ffi$, where $(\bar p,\bar q)$ are new variables. In the new variables the Hamiltonian takes the form (bars are omitted, we keep the same notations for the functions $\Lambda$ and $A$): H = (p,q) + 12 g(p,q)K\^2 + A(p,q)+(p,q)(p,q) + F, \[2.6\] where $\beta(p,q) = \{I_R,\Lambda\}$, $\{\cdot,\cdot\}$ denotes the Poisson bracket with respect to $(p,q)$, and we have introduced the so-called pendulum-like Hamiltonian $F$. The coefficients $g,A,$ and $\beta$ in $F$ depend on slow variables $p,q$, while the evolution of $p,q$ is defined by Hamiltonian $\Lambda$. If $A(p,q)>\beta(p,q)$, the phase portrait of $F$ on the $(\ffi,K)$-plane has a saddle point and a separatrix, see Fig. 1. The area $S$ of the region inside the separatrix loop can be found as S(p,q)=2 \_[\_[min]{}]{}\^[\_1]{} K = \_[\_[min]{}]{}\^[\_1]{} , \[2.7\] where $F_s$ is the value of $F$ at the saddle point, $\ffi_1$ and $\ffi_{min}$ are shown in Fig. 1.
![Phase portrait of Hamiltonian $F$ in (\[2.6\]) in the case $A(p,q)>\beta(p,q)$. It is assumed that $g,\beta$ are positive. \[fig:phase\]](fig1){width="14cm"}
Closed phase trajectories on the phase portrait of the pendulum-like Hamiltonian $F$ correspond to phase points captured into the resonance, while open trajectories correspond to those passing through the resonance. If $S$ grows, there appears additional phase volume inside of the separatrix loop, and phase points can be captured into the resonance. Motion on the phase portrait is fast compared to the speed of variation of $p,q$. Hence, the area surrounded by a captured trajectory is an adiabatic invariant of this system. Therefore, while the area $S$ grows, the phase point stays within the separatrix loop. If later $S$ decreases, the phase point can leave the separatrix loop when the area $S$ again equals the same value as at the time of capture. This is an escape from the resonance. Hence to predict the escape from the resonance one can use the time profile of the function $S(p,q) = S(t)$ along the resonant trajectory where the evolution of $(p,q)$ is defined by the Hamiltonian $\Lambda$. On the other hand, capture into the resonance is possible only if the phase point approaches the resonance when the function $S(t)$ grows.
While a phase point is captured, the corresponding value $h$ of the Hamiltonian $H_0$ of the averaged system (\[2.4\]) varies with time. The value $h$ can be used to parametrize function $S$, and it is useful to consider $S$ as a function of $h$: $S=S(h)$. We assume that $S(h)$ has the only maximum at $h = h_{max}$ (see Fig. 2). Thus, phase points captured at $h_- < h_{max}$ are transported in Fig. 2 to the right and escape from the resonance at $h_+ < h_{max}$ such that $S(h_+)=S(h_-)$. One can see that a capture followed by escape from the resonance result in strong (of order $1$) variation of the value of $h$ (and of the value of $I$, see (\[2.40\])).
![Plot of the area $S$ as a function of the particle energy $h$. \[fig:plot\]](fig2){width="14cm"}
Capture into a resonance is a probabilistic process (see [@Neishtadt99]). Consider a small time interval $\Dt t$. The probability of capture can be calculated as the ratio of the number of phase points captured into the resonance during this interval (i.e., $\sim \Dt t \dot S$) to the total number of phase points crossing the resonant curve. Thus one obtains the following formula for the probability of capture into the resonance: = , {S,}>0,\
\[2.8\]\
= 0, {S,} 0. One can see from (\[2.8\]) and (\[2.7\]) that the capture probability is a small value of order $\sqrt\eps$.
Phase points that cross the resonant curve without capture are scattered on the resonance. The scattering results in a small variation $\Dt I \sim \sqrt\eps$. Exact amplitude of scattering is a random value (see, e.g., [@Neishtadt99; @NV06]). If we have an ensemble of phase points, the mean scattering amplitude is (see [@Neishtadt99]) I = -(), \[2.9\] where $\langle \cdot \rangle$ denotes the ensemble average. In terms of the particle energy $h$, the mean scattering amplitude is h = -() v\_. \[2.10\]
To summarize, suppose we have an ensemble of phase points with the same initial value of $h$. After crossing the resonance, a small part of this ensemble given by (\[2.8\]) is captured into the resonance and its energy significantly changes. The other phase points of the original ensemble are scattered on the resonance with the mean variation of energy given by (\[2.10\]). Generally speaking, on each period $\tau(h)$ of the slow motion a phase trajectory of the averaged system crosses the resonance several times. Assume for simplicity that $A \ne 0$ at only one of these crossings. (Such situations occur in physical problems, see, e.g., [@ANVM17]). Repeated passages through the resonance result in drift and diffusion of $h$. Introduce the drift velocity and the diffusion coefficient as V\_h =h /(h), D\_[hh]{} = (h)\^2 /(h). \[eq2\]
Next step is to establish the relation between the capture probability $\Pi$ and the drift velocity $V_h$. From (\[2.8\]) and (\[2.40\]) one obtains (if $\{S,\Lambda\}>0$): = . |\_[I=I\_R]{}= v\_ = (). \[2.11\] Comparing this expression with (\[2.10\]), we find = - . \[2.12\]
Evolution of the distribution function.
=======================================
Consider the distribution function of the phase points $f(h,t)$. The kinetic equation for this distribution function has a general form = L\_s f+ L\_c f, \[eq0\] where operators $L_s$ and $L_c$ are related to scattering and capture/escape processes, respectively. The scattering part has a standard form L\_s f = - + 12 ( [D\_[hh]{} ]{} ) + L\_[sm]{} f. \[eq1\] Here $V_h, D_{hh}$ are drift and diffusion coefficients respectively, defined in the previous section, and $L_{sm}$ is an additional small ($\sim D_{hh}$) drift term. This term appears because $V_h$ is calculated in the principal order in $\sqrt\eps$, and it will be omitted in the following consideration.
We assume that the function $S(h)$ has only one maximum at $h = h_{max}$. The capture/escape operator in (\[eq0\]) has different forms for $h<h_{max}$ (capture) and $h>h_{max}$ (escape from the resonance). In the case of capture, $h<h_{max}$, we have L\_c f = -, \[eq3\] where $\Pi(h)$ is the probability of capture and $\tau = \tau(h)$ is the period of the averaged motion. Using (\[2.12\]) we find from (\[eq3\]) L\_c f = . \[eq4\]
In the case of escape, $h>h_{max}$, introduce $h_*$ as the value of the energy that the phase point had before the capture to escape with energy $h$. Denote $\Pi_* = \Pi(h_*), \, \tau_* = \tau(h_*), \, f_* = f(h_*,t)$. Then we have L\_c f &=& | | = - = - f\_\*\
&=& - () f\_\*\
&=& - () f\_\* = . Substituting the above expressions into (\[eq0\]) and using (\[eq2\]) we obtain the following form of the kinetic equation:
At $h<h_{max}$ = - V\_h + V\_h f + 12 ( [D\_[hh]{} ]{} ) ; \[eq6\]
at $h>h_{max}$ = - V\_h - ( [f - f\_\* ]{} ) + V\_h f\_\* + 12 ( [D\_[hh]{} ]{} ) . \[eq7\] In [@ANVM17], we omitted smaller terms with $\tau^{-1}\pt\tau/\pt h$ in equation (\[eq6\])-(\[eq7\]). This does not affect significantly the numerical results. However, now we keep these terms to proceed to a more concise form of the kinetic equation.
One can rewrite kinetic equation (\[eq6\])-(\[eq7\]) using the action variable of the averaged system $J$ instead of the energy $h$. According to the Hamiltonian equations of motion, these two variables are interconnected via $\pt h/\pt J = 2\pi/\tau$. Using this relation we introduce $\tilde f(J,t), \, V_J, \, D_{JJ}$ in place of $f(h,t), \, V_h, \, D_{hh}$ in the kinetic equation and take into account that f = , V\_h = , D\_[hh]{} = . After straightforward calculations we finally obtain the kinetic equation in terms of the action $J$ (we omitted tildes over $f$):
At $h<h_{max}$ = - V\_J + 12 ( [D\_[JJ]{} ]{} ) ; \[eq8\]
at $h>h_{max}$ = - V\_J - ( f - f\_\* ) + 12 ( [D\_[JJ]{} ]{} ) . \[eq9\]
One can find numerical evidence supporting validity of kinetic equations (\[eq6\]-\[eq9\]) in our paper [@ANVM17].
Acknowledgements {#acknowledgements .unnumbered}
================
The work of A. Artemyev, A. Neishtadt, and A. Vasiliev was supported by the Russian Scientific Fund, Project No. 14-12-00824.
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A. I. Neishtadt and A. A. Vasiliev, Destruction of adiabatic invariance at resonances in slow-fast Hamiltonian systems, Nucl. Instr. Meth. Phys. Res. A 561, 158 (2006).
A. P. [Itin]{}, A. I. [Neishtadt]{}, A. A. [Vasiliev]{}, [Captures into resonance and scattering on resonance in dynamics of a charged relativistic particle in magnetic field and electrostatic wave]{}, Physica D: Nonlinear Phenomena 141 (2000) 281–296. [](http://dx.doi.org/10.1016/S0167-2789(00)00039-7).
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There is a moment – near the end, so I will not specify – in Mission: Impossible – Fallout during which I genuinely could not believe my eyes. I took in the information onscreen, registered to some extent the effort it must have took to create this image, and could not believe or fully understand how it came to be in front of me. This sensation did not much let up for the remainder of the film, which, while not the strongest of the series, is so audacious to be almost absurd, so inventive that it elicits laughter purely because some response is required, and so masterfully executed you’d think every action scene was crafted in the safety of a computer or soundstage, which it most certainly was not. For a series its star, Tom Cruise, seemed to increasingly be using as a means of pushing himself physically, this is its ultimate achievement, the best marriage of outrageous stunt work, set piece, and narrative. It’s honestly beautiful to behold.
The title suggests a sort of long denouement, and in every way except its suggestion of calm, that’s fairly accurate – Fallout ties together so many threads that have been left dangling ever since Ethan Hunt (Cruise) wound up back in prison at the start of Ghost Protocol after giving up the rough life for a happy home at the end of Mission: Impossible III. Here, after losing some plutonium (whoops), Ethan is roped into breaking Rogue Nation villain Solomon Lane (Sean Harris) out of custody as a sort of trade to regain it, lest it fall into the wrong hands and, you know, blow up everything. As always, his bosses at IMF are all over his ass with oversight, and are sending an agent Walker (Henry Cavill) to watch over the operation. Walker is more by-the-books than Ethan, which mostly seems to amount to his preference for a plan versus just making it all up as he goes along. Benji (Simon Pegg) and Luther (Ving Rhames) happily go along as they always do, and before long they run back into their Rogue Nation mostly-ally Ilsa Faust (Rebecca Ferguson), who once again is working to similar-but-potentially-destructive ends to the team’s goals.
As one would hope, there’s much ado about who’s working for whom and what they hope to gain from every exchange. This reaches its ecstatic high when, midway through the film, we – and soon Ethan himself – realize that we have no idea who exactly is chasing him, and that it no longer much matters. More than I recall from past films, Fallout forces Ethan and his team to make most of their decisions moment to moment, rarely letting them design the terms on which they embark.
This approach especially seems to suit Cruise, who now in his mid-50s is doing more and more outlandish stunts every time out. The publicity team is really pushing the skydiving sequence – which, don’t get me wrong, is a blast – but that is honestly nothing compared to the truly insane finale that seems designed to kill its star. Yet by keeping the focus throughout the film, right from the very beginning when Ethan has to choose between saving Luther and saving the plutonium, on the immediate obstacles Ethan faces rather than the large goal, these stunts are a reflection of not only Fallout’s themes, but Ethan’s whole ethos. It’s easy to forget now, as the series hits its twenty-second birthday, that the first film began with Ethan’s entire team murdered, him the last man standing. When he repeatedly tells a worried Benji that he’ll keep him safe, this is the word of a man who knows the cost of these missions.
The stunt work underlines this by clarifying the danger they’re all in at every moment. Through what is essentially yet another race-against-the-clock scenario, we feel every hurdle to reach there. There’s no question, six films in, that Ethan will save the day. The question has always been how he’ll do it and what he’ll risk getting there. By placing himself in outrageous danger, Cruise is not only thrilling audiences in ways we really never see anymore, but also committing to the threat of every single moment. It’s not just something like a skydive gone wrong, or an impromptu helicopter flight; it’s seeing him race a motorcycle between two cars moving opposite directions, or bounding a staircase at full running speed. It’s all these little moments that last a fraction of a second but could easily end him. That’s what makes it all seem Impossible, not Ethan’s own determination to survive and save the day, but carry his team through with him.
Christopher McQuarrie returns as writer/director after making an outstanding entry to the series with Rogue Nation. There was some concern among those of us who love this series that it would lose its distinctiveness along the way, as each prior film brought in a new director who found something different in the premise to emphasize and play with. But Fallout is a surprisingly distinctive film from its predecessor. Rob Hardy takes over from cinematographer Robert Elswitt, some of the shadows leaving with the Oscar winner, and more movement brought to bear. This a more brutal film, its action sequences designed around the physical difficulty rather than the beauty that Rogue Nation so loved. That film’s romance is replaced here the male competition between Ethan and Walker, and unlike Ethan’s showdown with Brandt in Ghost Protocol, this one isn’t entirely designed to make Tom Cruise look good. Walker quite often has the more effective approach, and is far more formidable than Ethan in a fight.
Cruise, on the whole, is really starting to show his age. As a longtime fan of Tom Cruise Running, Fallout has far and away the most thrilling Tom Cruise Running shot I’ve ever seen, but Cruise is no longer the flawless physical machine he was even seven years ago. You can see him strain a bit, huffing and puffing and grappling with every inch he crosses. Far from making the effort pathetic, though, this only heightens the danger. Each film out, Cruise has sought the make the mission more and more impossible. He’s holding up his end by raising the stakes of his stunts; age, too, has continued to raise them. | https://criterioncast.com/reviews/theatrical/scott-reviews-christopher-mcquarries-mission-impossible-fallout-theatrical-review |
In addition to researchers on the lookout for seabirds, the Oscar Dyson is also hosting researchers hoping to catch a glimpse of some the world’s largest animals: marine mammals. Either ocean dwelling or relying on the ocean for food, marine mammals include cetaceans (whales, porpoises, and dolphins), manatees, sea lions, sea otters, walrus, and polar bears. Although marine mammals can be enormous in size (the largest blue whale ever recorded by National Marine Mammal Laboratory scientists was 98 feet long or almost the length of a ten story building laid on its side!), studying marine mammals at sea can be challenging as they spend only a short time at the surface. Joining the Dyson from the NMML on this cruise are Suzanne Yin, Paula Olson, and Ernesto Vazquez. As a full time observer, Yin spends most of the year on assignment on various vessels sailing on one body of water or another and only occasionally is to be found transitioning through her home of San Francisco, California. Paula calls San Diego, California home and spends most of her time when not observing at sea working on a photo identification database of blue and killer whales. Ernesto is a contract biologist from La Paz, Mexico and has been working on and off with NOAA for several years. Ernesto has worked with several projects for the Mexican government including ecological management of the Gulf of California Islands. | https://noaateacheratsea.blog/category/richard-chewning/ |
1. Introduction {#sec1}
===============
Passive immunization using antibodies has been used successfully for treatment and prophylaxis of infectious disease in humans, and there is increasing interest in the use of antibodies for treatment of infectious diseases that may be used as terrorist weapons, but for which the risk is not sufficiently high to justify preventive vaccination of a large civilian population (see \[[@B1]--[@B4]\] and references therein). Toxins are an important potential target for designing therapies against these threats and a broad range of approaches have been taken to develop inhibitors that may be of prophylactic or therapeutic use \[[@B1], [@B5]\].
Antibody engineering techniques allow affinity maturation of antibodies, and these techniques are being exploited to produce inhibitors for a number of toxins \[[@B6], [@B7]\]. The emphasis of this approach is on producing reagents with high affinity, based on the proposition that higher affinity will provide better protection.
However affinity, by itself, is a poor predictor of protective or therapeutic potential. Antibodies with high in vitro affinity for toxins do not automatically confer protection in vivo \[[@B8], [@B9]\] and may exacerbate the toxicity \[[@B10], [@B11]\]. The effects of using multiple antibodies with high affinities may be additive \[[@B12]\] or synergistic \[[@B8]\] or without effect \[[@B9]\]. In addition, epitope specificity \[[@B13]\], antibody titre \[[@B14]--[@B18]\], and dissociation rate \[[@B19]\] have been correlated with protection.
Toxins are produced by a number of plants, animals and microorganisms. Toxins may act at the cell surface and either damage the cytoplasmic membrane or bind to a receptor and act via transmembrane signalling subsequent to that binding \[[@B20]\]. Alternatively, toxins may cross the cell membrane and act on intracellular targets \[[@B20]\]. For example, anthrax lethal toxin, ricin and cholera toxin bind to a cell surface receptor and make use of cellular membrane trafficking to enter the cell \[[@B21], [@B22]\].
The objective of this study is to develop a simple mathematical model that may be used to predict the optimum antibody parameters (kinetic constants and concentration) needed to inhibit the binding of the toxin to its receptor. These predictions may be used to select candidate antibodies for progression to in vivo evaluation and to assess the potential value of affinity enhancement.
This paper is an extension to our previous work \[[@B23]\]. In the model presented in the following we explicitly take into account the process of toxin internalization and diffusive fluxes around the cell.
2. Model {#sec2}
========
The kinetic model describing the interactions of toxins with cell receptors can be formulated based on the well-known analytical framework for ligand-receptor binding. The models of this process have been studied for many years and a vast amount of literature has accumulated on this subject (see \[[@B24]--[@B27]\] and references therein).
When a toxin diffuses in the extracellular environment and binds to the cell surface receptors, the toxin concentration will vary in both space and time. Any rigorous description of this process would entail a system of Partial Differential Equations (PDE), which couples extracellular diffusion with reaction kinetics of the cell surface. The resulting system of PDE is nonlinear and too complex to be treated analytically. This complexity makes any comprehensive study of parameter optimization unfeasible. From another perspective, it is well known that under some rather broad conditions (see \[[@B24]--[@B27]\] and references therein) the reaction-diffusion system of the ligand-receptor binding can be well approximated by a system of Ordinary Differential Equations in which the spatial variability of the process is simulated by different concentrations of species in initially predefined spatial domains (called compartments). Although this compartment model is significantly simpler than the initial reaction-diffusion system, it still allows a consistent description of reaction-diffusion transport in underlying system \[[@B28], [@B25], [@B27]\]. In the current paper we use the compartment-model approach for our analytical study and numerical simulations.
To begin, we consider the following simple model. The toxin, *T*, binds reversibly to cell surface receptors, *R*, with a forward rate *k* ~1~ and a reverse rate *k* ~−1~ to form the toxin-receptor complex *C* ~*R*~ which is then slowly internalized at a rate *k* ~3~. The neutralizing antibody binds competitively to the toxin with on and off rates of *k* ~2~ and *k* ~−2~, respectively. The antibody-toxin complex, *C* ~*A*~, remains in the extracellular space (see [Figure 1](#fig1){ref-type="fig"}).
We can easily write an equation for the toxin-receptor binding (namely, without antibody being present). For a spherical cell of radius *a* with the toxin binding to its surface \[[@B24]--[@B27]\], $$\begin{matrix}
{\frac{dC_{R}}{dt} = k_{f}^{e}RT + k_{r}^{e}C_{R},} \\
\end{matrix}$$ where *C* ~*R*~ is the concentration of the bound receptors (toxin-receptor complexes), *R* is the concentration of receptors, and *T* is the bulk toxin concentration (i.e., far from the cell surface) and is assumed to be spatially uniform. The effective forward and reverse rate coefficients are defined by \[[@B24]--[@B27]\] $$\begin{matrix}
{k_{f}^{e} = \gamma k_{1},\quad\quad k_{r}^{e} = \gamma k_{- 1},} \\
\end{matrix}$$ where *k* ~1~, *k* ~−1~ are intrinsic reaction rates, *k* ~*D*~ = 4*πaD* is the diffusion rate, *D* is the diffusivity of toxin in the extracellular space, and *γ* = 1/(1 + *Rk* ~1~/*k* ~*D*~) ≤ 1 \[[@B28]--[@B26]\].
The bulk concentration of toxin *T* is mainly driven by the binding to antibody. Therefore, in this case we can write an equation system similar to ([1](#EEq1){ref-type="disp-formula"}) but without any "diffusive" modification of the intrinsic rate constants: $$\begin{matrix}
{\frac{dC_{A}}{dt} = k_{2}AT + k_{- 2}C_{A},} \\
\end{matrix}$$ where *C* ~*A*~ is the concentration of toxin-antibody complexes and *A* is the concentration of antibody.
The process of toxin internalization is phenomenologically introduced into our model by the following equation: $$\begin{matrix}
{\frac{dT_{i}}{dt} = k_{3}C_{R},} \\
\end{matrix}$$ where *T* ~*i*~ is the concentration of internalized toxin. The corresponding term should be included in ([1](#EEq1){ref-type="disp-formula"}), so we arrive at modified expression for *k* ~*r*~ ^*e*^ $$\begin{matrix}
{k_{r}^{e} = \gamma k_{- 1} - k_{3}.} \\
\end{matrix}$$
The systems ([1](#EEq1){ref-type="disp-formula"}), ([3](#EEq3){ref-type="disp-formula"}), and ([4](#EEq4){ref-type="disp-formula"}) should be supplemented with three conservation laws for concentrations of *R*, *T*, and *A*: $$\begin{matrix}
{R_{0} = R + C_{R},} \\
\end{matrix}$$ $$\begin{matrix}
{A_{0} = A + C_{A},} \\
\end{matrix}$$ $$\begin{matrix}
{T_{0} = T + C_{T} + C_{A} + T_{i},} \\
\end{matrix}$$ where *R* ~0~, *T* ~0~, and *A* ~0~ are the initial concentrations.
Equations ([1](#EEq1){ref-type="disp-formula"}), ([3](#EEq3){ref-type="disp-formula"}), ([4](#EEq4){ref-type="disp-formula"}), and ([6](#EEq6){ref-type="disp-formula"})--([8](#EEq8){ref-type="disp-formula"}) form a framework for our analysis. This is a system of nonlinear ODE (because of conservation laws ([6](#EEq6){ref-type="disp-formula"})--([8](#EEq8){ref-type="disp-formula"}) and because effective rates *k* ~*f*~ ^*e*^, *k* ~*r*~ ^*e*^ are functions of the receptor concentration). It can be easily solved numerically and also allows some analytical progress (see the following). If parameter *γ* ≪ 1 (and this is the case in many practical situations), then this model can be reduced to the "well-mixed" kinetic model with constant kinetic rates \[[@B23]\].
It is worth emphasizing that the aim of our analytical framework is to develop a simple but scientifically rigorous model that may be used to predict the optimum antibody kinetic properties and concentration required to achieve a desired protective effect rather than develop a detailed, biologically accurate model that captures all the details of the toxin internalization process. Therefore, the model does not take into account the pharmacokinetics of the toxin-antibody complex \[[@B11]\] or receptor internalization and recycling \[[@B30], [@B31]\]. *k* ~3~ is a lumped constant that describes all the processes that result in the appearance of the free toxin in the intracellular space \[[@B32]\]. Wiley and Cunningham \[[@B33]\] and Shankaran et al. \[[@B34]\] have also developed mathematical models of this type of process.
We are particularly interested in the behaviour of the model under conditions most likely to reflect the real biological situation, that is, toxin concentration much lower than the concentration of receptors (*T* ~0~/*R* ~0~ ≪ 1).
Testing of the model was carried out using `COPASI` (software application for simulation and analysis of biochemical networks and their dynamics \[[@B35]\]) and the kinetic parameters for the binding of ricin to its receptor and its internalization \[[@B36]\] and competition by the monoclonal antibody 2B11 \[[@B8]\]. The kinetic parameters used are shown in [Table 1](#tab1){ref-type="table"}. The value of *k* ~3~ used is that determined by Sandvig et al. \[[@B36]\] to be the rate of irreversible binding of ricin to HeLa cells. For simplicity, the simulation was carried out using all reactions taking place in the same compartment.
To illustrate the model, we used toxin and receptor concentrations based on cell culture studies carried out in our laboratory. These typically use a cell concentration of 1 · 10^4^ cells per 100 *μ*L experiment and a ricin concentration of 10 pM. Assuming 3 · 10^7^ receptors/cell \[[@B36]\], the receptor concentration is approximately 5 nM.
3. Analytical Results {#sec3}
=====================
3.1. Cell Surface Binding {#sec3.1}
-------------------------
Initially we derive some analytical results for toxins that act at the cell surface and are not internalized; that is, we set *k* ~3~ = 0 in ([4](#EEq4){ref-type="disp-formula"}). At equilibrium *d*/*dt* = 0 and from ([1](#EEq1){ref-type="disp-formula"}) and ([3](#EEq3){ref-type="disp-formula"}) we can write $$\begin{matrix}
{C_{R} = \frac{RT}{K_{1}},\quad\quad C_{A} = \frac{AT}{K_{2}},} \\
\end{matrix}$$ where *K* ~1~ = *k* ~1~/*k* ~−1~, *K* ~2~ = *k* ~2~/*k* ~−2~ are the association constants for the toxin binding to the receptor and antibody, respectively. It is worth noting that the parameter *γ* (diffusive correction of the intrinsic reaction rates) disappears from ([9](#EEq9){ref-type="disp-formula"}), so in this case the analytical results are identical to ones derived using the "well-mixed" approximation \[[@B23]\].
In order to simplify notations, we denote by *z* and *y* the equilibrium concentrations of the toxin-receptor and toxin-antibody complexes; that is, $$\begin{matrix}
{z = \left\lbrack C_{R} \right\rbrack_{\text{eq}},\quad\quad y = \left\lbrack C_{A} \right\rbrack_{\text{eq}}.} \\
\end{matrix}$$ From ([9](#EEq9){ref-type="disp-formula"}) and conservation laws ([6](#EEq6){ref-type="disp-formula"})--([8](#EEq8){ref-type="disp-formula"}) the following closed equation for *z* can be derived: $$\begin{matrix}
{\left( R_{0} - z \right)\left( T_{0} - z - y \right) - K_{1}z = 0,} \\
\end{matrix}$$ $$\begin{matrix}
{y = A_{0}\frac{\epsilon z}{R_{0} - z\left( 1 - \epsilon \right)},} \\
\end{matrix}$$ where *ϵ* = *K* ~1~/*K* ~2~.
Equation ([11](#EEq11){ref-type="disp-formula"}) can be written in a more conventional form of a cubic equation as follows: $$\begin{matrix}
{a_{3}z^{3} + a_{2}z^{2} + a_{1}z + a_{0} = 0,} \\
\end{matrix}$$ where $$\begin{matrix}
{a_{3} = \epsilon - 1,} \\
{a_{2} = \left( {1 - \epsilon} \right)C_{0} + \epsilon A_{0} + R_{0},} \\
{a_{1} = - R_{0}\left( C_{0} + A_{0} + \left( 1 - \epsilon \right)T_{0} \right),} \\
{a_{0} = T_{0}R_{0}^{2},} \\
\end{matrix}$$ and *C* ~0~ = *R* ~0~ + *K* ~1~.
It is well known that ([13](#EEq13){ref-type="disp-formula"}) has a closed-form analytical solution (Cardano\'s formula \[[@B37]\]), which in our case provides a consistent way to derive exact solutions for the proposed model. Unfortunately these solutions still involve rather cumbersome expressions, which require further simplifications in order to be used in practical situations. In the following we present another approach that explicitly employs the smallness of ratio *T* ~0~/*R* ~0~ ≪ 1 and leads to a simple analytical expression for the protective properties of the antibody.
We observe that in the absence of antibody (i.e., *A* ~0~ = 0), ([11](#EEq11){ref-type="disp-formula"}) is an elementary quadratic equation that has two roots. If we impose the obvious constraint *z* → 0 as *T* ~0~ → 0, then there is only one solution, which we designate as *z* ~0~: $$\begin{matrix}
{z_{0} = \frac{C_{0}}{2}\left\lbrack {1 - \left( {1 - \frac{4R_{0}T_{0}}{C_{0}^{2}}} \right)^{1/2}} \right\rbrack.} \\
\end{matrix}$$ Under the condition *T* ~0~/*R* ~0~ ≪ 1, this can be simplified to $$\begin{matrix}
{z_{0} \approx \frac{R_{0}T_{0}}{C_{0}},\quad\quad C_{0} = R_{0} + K_{1}.} \\
\end{matrix}$$
Let us now evaluate the effect of adding an antibody. From a mathematical point of view this effect (i.e., change of *z* under condition *A* ~0~ \> 0) is captured entirely by the term *y* in ([11](#EEq11){ref-type="disp-formula"}), so our aim is to provide a reasonable analytical estimation of this term.
From ([12](#EEq12){ref-type="disp-formula"}) and based on our initial assumption of low toxin concentration (*T* ~0~/*R* ~0~ ≪ 1), we can deduce the following simple estimate *y* ≈ *ϵzA* ~0~/*R* ~0~. This then leads to a modified form of ([11](#EEq11){ref-type="disp-formula"}) as follows: $$\begin{matrix}
{\left( R_{0} - z \right)\left( T_{0} - z \right) - K_{\ast}z = 0,} \\
\end{matrix}$$ where $$\begin{matrix}
{K_{\ast} = K_{1} + \epsilon A_{0}.} \\
\end{matrix}$$
We can see that this is the same form as the equation for *z* when *A* ~0~ = 0, but now with *K* ~1~ replaced with *K* ~∗~. This also implies that the analytical solution ([16](#EEq15){ref-type="disp-formula"}) is still valid but only with the substitution *K* ~1~ = *K* ~∗~.
In order to characterize the effect of an antibody on the binding of a toxin to its receptor, we introduce the nondimensional parameter Ψ, the relative reduction in *C* ~*R*~ due to the introduction of an antibody as follows: $$\begin{matrix}
{\Psi \equiv \frac{z\left( A_{0} > 0 \right)}{z\left( A_{0} = 0 \right)}.} \\
\end{matrix}$$ The analytical results presented previously enable us easily to derive a simple formula for the antibody efficiency parameter Ψ. By using ([10](#EEq10){ref-type="disp-formula"}), ([16](#EEq15){ref-type="disp-formula"}), ([18](#EEq17){ref-type="disp-formula"}), and ([19](#EEq18){ref-type="disp-formula"}), we can readily deduce the following: $$\begin{matrix}
{\Psi = \frac{1}{1 + \epsilon\lambda},\quad\quad\epsilon = \frac{K_{1}}{K_{2}},\quad\quad\lambda = \frac{A_{0}}{C_{0}}.} \\
\end{matrix}$$ This expression is the main result of the current paper and will be validated with numerical simulations.
To conclude this section let us briefly discuss some additional constraints for the parameters of our model in order for the expression ([20](#EEq19){ref-type="disp-formula"}) to be valid. As mentioned above the condition of low toxin concentration is always assumed in our study. Another simple condition can be derived from the constraint *C* ~*R*~ + *C* ~*A*~ ≤ *T* ~0~ and by using ([16](#EEq15){ref-type="disp-formula"}): $$\begin{matrix}
{\frac{R_{0}}{C_{0}}\left( 1 + \epsilon\frac{A_{0}}{C_{0}} \right) \approx \epsilon\frac{R_{0}A_{0}}{C_{0}^{2}} \leq 1,} \\
\end{matrix}$$ since *R* ~0~/*C* ~0~ ≤ 1. This condition could always be checked retrospectively and always hold in our numerical simulations.
3.2. Toxin Internalization {#sec3.2}
--------------------------
For toxins that are internalized, the effect of antibodies that prevent receptor binding is to reduce the effective rate of internalization. To examine and evaluate this effect, we need to analyze the full systems ([1](#EEq1){ref-type="disp-formula"}), ([3](#EEq3){ref-type="disp-formula"}), and ([4](#EEq4){ref-type="disp-formula"}).
In order to characterize the effect of antibody concentration on the rate of toxin internalization, we introduce a new parameter as follows: $$\begin{matrix}
{G = \frac{T_{i}\left( A_{0} > 0 \right)}{T_{i}\left( A_{0} = 0 \right)},} \\
\end{matrix}$$ which is a function of time (i.e., *G* ≡ *G*(*t*)).
Our aim is to deduce function *G* based on the kinetic models ([1](#EEq1){ref-type="disp-formula"}), ([3](#EEq3){ref-type="disp-formula"}), and ([4](#EEq4){ref-type="disp-formula"}). It is evident that *G* ≤ 1 for *t* \> 0 and *G* → 1 as *t* → *∞* (since in that case all toxin will be internalized).
For the toxins of interest, while the receptor binding is rapid (time sale \~1/(*k* ~1~ *C* ~0~)) \[[@B24], [@B25]\], the subsequent internalization is much slower (time scale \~1/*k* ~3~ ≫ 1/(*k* ~1~ *C* ~0~)). This coupling of slow and fast processes in our system allows us to develop a simplified model of toxin internalization using the well-known framework of Quasi-Steady-State Approximation (QSSA); see \[[@B24]--[@B27], [@B29]\] and refs therein.
When applied to our system, QSSA elucidates the toxin internalization as a two-stage process. After the initial rapid binding of the toxin to the receptor we can simply set *dC* ~*R*~/*dt* = 0 in ([1](#EEq1){ref-type="disp-formula"}). The further slow evolution of *T*(*t*) (namely, quasi-steady state) is completely determined by the conservation laws ([8](#EEq8){ref-type="disp-formula"}) and ([4](#EEq4){ref-type="disp-formula"}) and spans a time scale of the order of the internalization time (\~1/*k* ~3~). In addition, for solving ([4](#EEq4){ref-type="disp-formula"}) at the initial stage of internalization, we can assume that *T* ~*i*~ ≪ *T* ~0~ and write $$\begin{matrix}
{T_{i}\left( t \right) = k_{3}z_{0}t,\quad t \ll \frac{1}{k_{3}},} \\
\end{matrix}$$ where *z* ~0~ is given by expressions ([15](#EEq14){ref-type="disp-formula"}) and ([16](#EEq15){ref-type="disp-formula"}). The evolution of *T* ~*i*~(*t*) for the late stage of internalization can be readily derived from ([4](#EEq4){ref-type="disp-formula"}) and ([6](#EEq6){ref-type="disp-formula"})--([8](#EEq8){ref-type="disp-formula"}) by assuming \[*T* ~0~ − *T* ~*i*~(*t*)\] ≪ *T* ~0~: $$\begin{matrix}
{T_{i}\left( t \right) = T_{0}\left\lbrack 1 - \exp\left( - k_{3}t \right) \right\rbrack,\quad t \geq \frac{1}{k_{3}},} \\
\end{matrix}$$ so *T* ~*i*~(*t*) exponentially approaches its saturation limit. A simulation of this process is shown in [Figure 5](#fig5){ref-type="fig"}, and the slow linear increase of *T* ~*i*~ at the initial stage is clearly visible.
Now, consider the case where *A* ~0~ \> 0. According to ([23](#EEq22){ref-type="disp-formula"}) the main effect of the introduction of an antibody is to reduce the value of *z* ~0~, as described in the previous section. Then, based on ([22](#EEq21){ref-type="disp-formula"}), ([23](#EEq22){ref-type="disp-formula"}), and ([19](#EEq18){ref-type="disp-formula"}) we can conclude that, during the quasi-equilibrium stage, the following approximation holds: $$\begin{matrix}
{G = \frac{T_{i}\left( A_{0} > 0 \right)}{T_{i}\left( A_{0} = 0 \right)} \approx \Psi,} \\
\end{matrix}$$ where Ψ is given by expression ([20](#EEq19){ref-type="disp-formula"}).
The overall effect of introducing an antibody can be best described in terms of the internalization half-time, *τ* ~*i*~. Without antibody the latter can be estimated from ([24](#EEq23){ref-type="disp-formula"}) and condition *T* ~*i*~(*τ* ~*i*~) = *T* ~0~/2. Thus from ([23](#EEq22){ref-type="disp-formula"}) we yield $$\begin{matrix}
{\tau_{i} \approx \frac{T_{0}}{2k_{3}z_{0}} = \frac{C_{0}}{2k_{3}R_{0}}.} \\
\end{matrix}$$ For the internalization time with the presence of antibody we can apply reduced value of *z* ~0~ and write the following simple formula: $$\begin{matrix}
{\frac{\tau_{i}}{\tau_{i}^{0}} \approx \frac{1}{\Psi},} \\
\end{matrix}$$ where *τ* ~*i*~ ^0^ is the internalization time in the absence of antibody (*A* ~0~ = 0).
Equations ([26](#EEq25){ref-type="disp-formula"}) and ([27](#EEq26){ref-type="disp-formula"}) have a clear interpretation. As described in the previous section, the introduction of an antibody results in a decrease, at *t* ≪ *τ* ~*i*~, in the equilibrium value of *C* ~*R*~ (i.e., in *z* ~0~). This can be related, in accordance with ([23](#EEq22){ref-type="disp-formula"}) and ([26](#EEq25){ref-type="disp-formula"}), to a corresponding decrease in the concentration of internalized toxin *T* ~*i*~ and a consequent increase in the toxin internalization time (since it takes longer to achieve a give level of *T* ~*i*~). Since changes in *z* ~0~ can be described comprehensively by means of the parameter Ψ, it still remains the only parameter needed to characterize the influence of an antibody on the concentration of internalized toxin ([25](#EEq24){ref-type="disp-formula"}), ([27](#EEq26){ref-type="disp-formula"}).
It is evident that the two main effects described above (reduction of the concentration of internalized toxin at a given time and increase in the time required for the internalized toxin to reach a given concentration) are not independent of each other. The linear relationships ([25](#EEq24){ref-type="disp-formula"}), ([27](#EEq26){ref-type="disp-formula"}) allow us to establish a general identity that relates these two effects for any time *t*.
Let us assume that for *A* ~0~ = 0, *τ* ~0~ is the time taken for the internalized toxin to reach a concentration *T* ~*i*~ ^0^ (i.e., *τ* ^0^ = *T* ~*i*~ ^0^/(*k* ~3~ *z* ~0~); see ([23](#EEq22){ref-type="disp-formula"})). The effect of introducing an antibody is to reduce the internalized toxin concentration to a value *T* ~*i*~ ≤ *T* ~*i*~ ^0^. Then from ([25](#EEq24){ref-type="disp-formula"}), ([27](#EEq26){ref-type="disp-formula"}) we can derive the following identity: $$\begin{matrix}
{T_{i}\tau_{i} = T_{i}^{0}\tau_{i}^{0},} \\
\end{matrix}$$ where *τ* ~*i*~ is the time required for the internalized toxin to reach *T* ~*i*~ ^0^ when *A* ~0~ \> 0. The identity ([28](#EEq27){ref-type="disp-formula"}) has no explicit dependency on antibody kinetic parameters or concentration and provides an easy way to calculate any of the parameters (*T* ~*i*~, *T* ~*i*~ ^0^, *τ* ~*i*~, *τ* ~*i*~ ^0^) if the other three are known.
4. Numerical Results and Discussion {#sec4}
===================================
We have derived an analytical expression for the parameter Ψ, the relative ability of an antibody to reduce the binding of a toxin to its receptor ([20](#EEq19){ref-type="disp-formula"}). Our derivation is based on the following assumptions:toxin concentration is much lower than the receptor concentration,for toxins that are internalized, the internalization rate is much slower than establishment of the receptor-toxin binding equilibrium.
Applying these assumptions, we found that parameter Ψ is independent of the toxin concentration (see ([20](#EEq19){ref-type="disp-formula"})); that is, it is determined by the ratio of antibody to receptor concentration and not by the ratio of antibody to toxin concentration as commonly used. For the low toxin/receptor ratios likely to occur in biological situations, the condition ([21](#EEq20){ref-type="disp-formula"}) can be met by large range of antibody kinetic parameters. From this point of view ([20](#EEq19){ref-type="disp-formula"}) should be valid for most practical applications.
The implications of our analytical findings are illustrated by simulation of the complete kinetic models (([1](#EEq1){ref-type="disp-formula"}),([3](#EEq3){ref-type="disp-formula"}), ([4](#EEq4){ref-type="disp-formula"}), and ([6](#EEq6){ref-type="disp-formula"})--([8](#EEq8){ref-type="disp-formula"})) using the kinetic constants for ricin and the anti-ricin antibody 2B11 ([Table 1](#tab1){ref-type="table"}). [Figure 2](#fig2){ref-type="fig"} is a simulation of the effect of the presence of an antibody on the binding of the toxin to its receptor (formation of *C* ~*R*~). The antibody concentration is expressed as the dimensionless parameter *λ* = *A* ~0~/*C* ~0~. In this case, since *R* ~0~ and *T* ~0~ ≪ *K* ~1~, the parameter *C* ~0~ = *R* ~0~ + *K* ~1~ is dominated by *K* ~1~ (1.08 · 10^−7^).
[Figure 3](#fig3){ref-type="fig"} shows the effect of increasing antibody concentration on Ψ. There is a good agreement between the values of Ψ determined from ([20](#EEq19){ref-type="disp-formula"}) and from ([19](#EEq18){ref-type="disp-formula"}) using the equilibrium values of *C* ~*R*~ determined from simulation of the complete kinetic model ([Figure 3](#fig3){ref-type="fig"}). For instance, the results predict that, for this toxin and antibody combination, the additional protection provided by increasing the antibody concentration diminishes rapidly when *λ* exceeds 0.1.
[Figure 4](#fig4){ref-type="fig"} shows the relationship ([20](#EEq19){ref-type="disp-formula"}) between Ψ, antibody concentration and the toxin/antibody and the ratio of toxin/receptor dissociation constants (*ϵ*). This plot is valid for all combinations of toxin, receptor, and antibody consistent with the assumptions used to derive ([20](#EEq19){ref-type="disp-formula"}), principally *T* ~0~ ≪ *R* ~0~. The antibody kinetic parameters and concentration required to provide a specified degree of protection may be determined from this plot. For example, any combination of *ϵ* and *λ* falling below the dashed line will reduce either *C* ~*R*~ or *T* ~*i*~ by 80%.
This, in turn, enables important judgements to be made about antibody selection. For example, if an antibody concentration of 0.25*C* ~0~ (*λ* = 0.25) is achievable, then an antibody with an *ϵ* value of 50 will provide good protection (93% reduction in *C* ~*R*~ or *T* ~*i*~). If an antibody concentration of only 0.05*C* ~0~ (*λ* = 0.05) is achievable, then an *ϵ* value of 250 is required to achieve the same level of protection. The structure of ([20](#EEq19){ref-type="disp-formula"}) is such that a given increase in protection (Ψ or Γ) may be achieved by either an *x*-fold increase in *ϵ* or an *x*-fold increase in *λ*.
The effect of antibody on toxin internalization is simulated in [Figure 5](#fig5){ref-type="fig"}. Rapid equilibration of receptor and toxin is followed by slow accumulation of toxin within the cell. Equation ([25](#EEq24){ref-type="disp-formula"}) predicts that Ψ is the only parameter needed to characterize the influence of an antibody on toxin internalization. [Figure 6](#fig6){ref-type="fig"} compares Γ calculated using ([25](#EEq24){ref-type="disp-formula"}), ([20](#EEq19){ref-type="disp-formula"}) with Γ determined using values of *T* ~*i*~ and *T* ~*i*~ ^0^ at *t* = 10^4^ sec from this simulated data and shows good agreement between the two values under the condition *T* ~0~ ≪ *R* ~0~, although the value of Γ is slightly greater than Ψ. The plot predicts the degree of protection provided by a given concentration of antibody and enables assessment of the value of increasing antibody concentration beyond a certain value. For example, to enhance the reduction of *T* ~*i*~ from 90% to 95% requires doubling of *A* ~0~.
The expression for Ψ, ([20](#EEq19){ref-type="disp-formula"}), assumes a quasi-equilibrium state in the system. In practice, this state may take significant time to be achieved. [Figure 7](#fig7){ref-type="fig"} shows a simulation of the time taken by the ricin/receptor/2B11 system to reach the quasi-equilibrium state for *λ* = 0.05. The value of Γ determined from the toxin internalization profiles ([Figure 7](#fig7){ref-type="fig"}) parallels this process; that is, experimental validation of Γ must allow sufficient time to elapse for the quasi-equilibrium state to be established.
The relationship between the internalization time *τ* ~*i*~ and Ψ described in ([27](#EEq26){ref-type="disp-formula"}) is shown in [Figure 8](#fig8){ref-type="fig"}. Ψ was determined from simulated toxin internalization time courses ([Figure 5](#fig5){ref-type="fig"}) as the time to internalize 5 · 10^−14^ M ricin. The slope of the fitted line is 1.07, close to the predicted value of 1.0.
In summary, the protection provided by an antibody against toxins that act either at the cell surface or after binding to the cell surface followed by internalization may be predicted from a simple kinetic model. Protection parameter Ψ is a simple function of antibody, receptor, and toxin concentrations and the kinetic parameters governing the binding of the toxin to the receptor and antibody: $$\begin{matrix}
{\Psi = \frac{1}{1 + \left( K_{1}/K_{2} \right)\left( A_{0}/C_{0} \right)}.} \\
\end{matrix}$$
The calculated value of Ψ matches closely the degree of protection determined from numerical simulation of the binding and internalization reactions and provides a convenient method for predicting the optimum antibody parameters (concentration and dissociation constants) needed to provide effective treatment or prophylaxis for toxins.
The authors acknowledge helpful discussions with Dr. Chris Woodruff and Dr. Ralph Leslie.
{#fig1}
{ref-type="table"}. *R* ~0~ = 5 nM, *T* ~0~ = 10 pM, *C* ~0~ = 1.15 · 10^−7^.](BMRI2013-230906.002){#fig2}
{ref-type="disp-formula"}) was determined from ([20](#EEq19){ref-type="disp-formula"}) (solid lines) and by using simulated values of *C* ~*R*~ from [Figure 2](#fig2){ref-type="fig"} at 2500 sec (△), *ϵ* = 25.9.](BMRI2013-230906.003){#fig3}
{ref-type="disp-formula"}) as a function of parameter *ϵ* = *K* ~1~/*K* ~2~ and *λ* = *A* ~0~/*C* ~0~ (([20](#EEq19){ref-type="disp-formula"})): *λ* = 0.01 (*⚪*); 0.025 (△); 0.05 (□); 0.1 (*▽*); 0.25 (*◊*). The range of values for *λ* and *ϵ* below dashed line corresponds to 80% protection.](BMRI2013-230906.004){#fig4}
{ref-type="table"}. *λ* = *A* ~0~/*C* ~0~, *R* ~0~ = 5 nM, *T* ~0~ = 10 pM, *C* ~0~ = 1.15 · 10^−7^, *ϵ* = 25.9.](BMRI2013-230906.005){#fig5}
{ref-type="table"}. Parameter Ψ (solid line) was determined from ([20](#EEq19){ref-type="disp-formula"}). *R* ~0~ = 5 nM, *T* ~0~ = 10 pM, *C* ~0~ = 1.15 · 10^−7^, *ϵ* = 25.9.](BMRI2013-230906.006){#fig6}
{ref-type="table"}. Γ (□) was determined using ([25](#EEq24){ref-type="disp-formula"}) and values *T* ~*i*~ and *T* ~*i*~ ^0^ at *t* = 10^4^ sec using simulated toxin internalization time courses. *R* ~0~ = 5 nM, *T* ~0~ = 10 pM, *C* ~0~ = 1.15 · 10^−7^, *λ* = 0.05.](BMRI2013-230906.007){#fig7}
{ref-type="disp-formula"}). Solid line is formula ([27](#EEq26){ref-type="disp-formula"}) and (□) is simulation with `COPASI`. *τ* ~*i*~ was determined as the time to internalize 5 · 10^−14^ M of ricin. All other parameters are the same as in [Figure 7](#fig7){ref-type="fig"}.](BMRI2013-230906.008){#fig8}
######
Kinetic constants used in numerical simulations (the binding of ricin to its receptor and the monoclonal antibody 2B11).
Reaction Value
---------- -------------------------
*k* ~1~ 1.3 · 10^5^ M^−1^s^−1^
*k* ~−1~ 1.4 · 10^−2^ s^−1^
*k* ~2~ 1.25 · 10^5^ M^−1^s^−1^
*k* ~−2~ 5.2 · 10^−4^ s^−1^
*k* ~3~ 3.3 · 10^−5^ s^−1^
[^1]: Academic Editor: Nirmal K. Ganguly
| |
It is true that both volume and area have a wide range of applications in everyday life. Despite the fact that we learn about area and volume at school, it is critical that we retain this knowledge for the remainder of our life. Both concepts are often misunderstood by the general public.
Despite the fact that volume and area seem to be almost same, this is not the case at all.
Area Vs. Volume
Because area refers to how much space an item occupies, volume refers to how much space an object holds. Shapes in the area are two-dimensional; those in the volume are three-dimensional. The capacity of a can, for example, is 5 liters, yet the can only covers 5 cm of the surface area.
While on a plane or flat surface, an object’s complete area is known as its perimeter. Objects with their own potential exist in the same way. A water tank, for example, has a specific capacity for holding water.
This is the water tank’s capacity. Remember that only things with a hollow interior have measurable volumes that can be plugged into formulas.
You may learn more about the differences between an object’s area and volume from the information provided in the following table and sections.
What is the purpose of Area?
The area of any thing is the whole 2-dimensional space that is covered by an object or form, as we learned in our math lessons. Basically, the area of an item informs us how much space it occupies on the surface of a flat object.
The dimensions of the provided form are simply multiplied to arrive at this result. The area of any item will give us the total number of squares of fixed sizes that are needed to cover the object. This is correct.
The square meter, abbreviated as m2, is the standard unit of area in the International System of Units. There are a variety of formulas that may be used to calculate the area of various forms. The following paragraphs cover a few of the most frequently used formulas.
In a square, the area is equal to the sum of its perimeters.
- Area: Length x Width = Rectangle
- Breadth x Height = Area of a Parallelogram
- (Breadth x Height) x 2 = Area of a Triangle
- A Circle’s Surface Area Is Defined As r2
What’s the current volume level?
Any object’s volume may be thought of as the amount of three-dimensional space contained inside a single closed surface.
In other words, it provides us with information on the object’s volume. The cubic meter, abbreviated m3, is the SI unit of volume. To put it another way, the volume of an item is just its overall capacity. A basketball or a soccer ball, for example, will contain a specified amount of air.
There are several formulas for calculating an object’s volume, just as there are numerous formulas for calculating an object’s area. To help you better understand these formulas, we’ve included their explanations below.
- a3 is the cubic unit’s volume.
- A Rectangular Prism’s volume is calculated as follows:
- A Sphere’s Volume: (4/3) x xr3
- A Cylinder’s volume may be calculated by multiplying its diameter by its height.
- Cone volume: (Height/3) (Height/2) x r2
Difference Between Area and Volume
In all cases, the term “area” refers to a two-dimensional object or surface. A three-dimensional item and its individual capability are defined by volume, on the other hand.
The area of a planar figure will always be greater than the volume of a solid object.
When we speak about an item’s area, we’re referring to the space encompassed by the object’s length and width, which are typically the length and breadth of the object. Volume refers to the sum of an object’s three dimensions: length, width, and height.
Square centimeters, square meters, and even square kilometers are used to quantify an object’s surface area. Cubic units, such as cubic centimeters, cubic meters, and cubic grams, are used to express volume.
The area of every two-dimensional form is always equal to the sum of its length and width. As a result, a volume is always present in any form with three dimensions: length, width, and height.
Area and Volume: Frequently Asked Questions
Is it possible to compare capacity and volume?
Volume refers to the amount of space an item occupies, while capacity refers to how much an object can hold or transport. Putting a bottle of water on a table, for example, fills in the empty space.
The volume is made up of all of this white space. However, the capacity of the bottle is determined by the volume of water it can hold, not by the volume of air it can hold.
Capacity and volume have some conceptual similarities, but they aren’t interchangeable ideas.
When comparing surface area and volume, how can you know which is which?
The term “area” refers to the size of a two-dimensional surface, such as a playground. It is possible to represent the area of a plane in a variety of units, such as square meters and square miles.
It is possible, however, to utilize the same surface in both 3D space and a 2D plane. Surface area, on the other hand, is a measure of an object’s visible surface area. As a result, the surface area is most typically utilized in the context of three-dimensional objects.
To illustrate this point, consider a cube, which has a surface area that equals the sum of the area of all six sides.
Which two volume formulae are there?
The volume of various forms and objects may be calculated using a variety of formulae.
Cuboid and prism formulae are the two most regularly utilized formulas.
lwh is the formula for calculating the cuboid’s volume. L stands for length, W for width, and H for height.
The volume of a prism may be calculated using the formula Bh. h=height, and B=base area.
What is the formula for determining a sphere’s area?
The formula for determining the sphere’s area is: A=4 r2
r represents for radius in this formula, where A stands for the area and stands for pi. Archimedes, the famed Greek philosopher, originally utilized this formula roughly two thousand years ago.
Conclusion
In light of the foregoing explanation, we all understand the difference between an area and a volume. Additionally, we know how to calculate the dimensions and volumes of any object.
Area and volume are two different mathematical notions, yet they vary in several ways.
An object’s area refers to the amount of space it occupies in two dimensions. Any three-dimensional item or figure’s volume relates to how much space it occupies.
Any two-dimensional shape or object may be measured in terms of its surface area using a variety of different formulas. For example, a square’s surface is measured using a different method than that of a triangle.
When it comes to measuring the volume of 3-D figures or objects, there are a number of various formulas that may be used. A cylinder’s volume is measured using a different formula than a sphere’s volume is measured using a different formula. | https://difference-between.net/difference-between-area-and-volume/ |
How do you find the proportion of a population?
How do you find the proportion of a population?
Formula Review p′ = x / n where x represents the number of successes and n represents the sample size. The variable p′ is the sample proportion and serves as the point estimate for the true population proportion.
What is the proportion of a population?
What is the Population Proportion? A population proportion is a fraction of the population that has a certain characteristic. For example, let’s say you had 1,000 people in the population and 237 of those people have blue eyes. The fraction of people who have blue eyes is 237 out of 1,000, or 237/1000.
How do you calculate true proportion?
Find the number of observations that meet the criterion in your sample. In our example, we would find how many of the children in our sample were boys. Divide this number by the total number of observations in the sample. This is the estimated proportion.
What is the point estimate of the population proportion?
sample proportion
The point estimate for the population proportion is the sample proportion, and the margin of error is the product of the Z value for the desired confidence level (e.g., Z=1.96 for 95% confidence) and the standard error of the point estimate.
How to calculate the difference between two population proportions?
Standardized Test Statistic for Hypothesis Tests Concerning the Difference Between Two Population Proportions The test statistic has the standard normal distribution. must lie wholly within the interval [0, 1].
What does probability have to say about sample proportion?
In Lesson 8 we learned what probability has to say about how close a sample proportion will be to the true population proportion. sample proportion = population proportion + random error. The Normal Approximation tells us that the distribution of these random errors over all possible samples follows the normal curve with a standard deviation of
How to calculate standard error for population proportion?
The standard error calculation involves estimating the true standard deviation by substituting the sample proportion for the population proportion in the formula. Luckily, this works well in situations where the normal curve is appropriate [i.e. when np and n (1-p) are both bigger than 5].
Which is the null hypothesis for a population proportion?
Thus, we reject the null hypothesis, H0: p = 0.40. Our sample data provide significant evidence that the population proportion is not 0.40, and in fact, is likely much less. This means that significantly fewer people had “a great deal” of confidence in public schools in the year 2005 compared with the year 1995. | https://www.handlebar-online.com/popular-questions/how-do-you-find-the-proportion-of-a-population/ |
Today, I was reading some comments from one of my previous posts on running. The comments were from readers of various posts. One reader had some nice things to say. I began to think what an appropriate post for January 1, 2018. Running for the Prize. OK, OK, yeah, I will be using an old post for a new post, again. The Blog Post Etiquette Police can advise me after the fact.
Let me start with saying I AM SO GLAD 2017 IS OVER! It has been a trying year, to say the least! I feel like I have been running and running and running all year. My family has gone through a great personal loss and my health has taken hit after hit after hit. I just know 2018 will be better.
I do feel, from time to time, that I am “Running for the Prize”. Sometimes it seems a spiritual prize and at other times, it’s just running for the prize to just finish the day and to get home to my quiet house with my father and my Zuckie (my standard dachshund). My home – my Solace .
If you know me at all, you know that I do love my home. I love to be at home and I love my family. So, with that said, I will tell you that I do long for the time when I finish this race that we call “life”. When that occurs for me, I will be home where my heart has always been. In the presence of my Lord and Savior, Jesus Christ. But until that day, I will continue to run this race on earth. Striving to make the most of each moment in this race for the prize. Striving to forget the past and pressing on towards the future because that is where the prize is.
13 Brothers, I do not consider that I have made it my own. But one thing I do: forgetting what lies behind and straining forward to what lies ahead, 14 I press on toward the goal for the prize of the upward call of God in Christ Jesus. 15 Let those of us who are mature think this way, and if in anything you think otherwise, God will reveal that also to you.
So, with that said… I will continue with this old post made new, once again.
Have you ever seen a dachshund race? Oh My Goodness! It is the funniest thing I have ever seen! I follow a little dachshund on Facebook and he is quite the celebrity! His name is Crusoe and he is from Canada. He was in a “wiener dog race” and he finished 3rd and the prize was a squeaky ball! (see it here and if you still want more see his blog… here) It is so much fun and the funniest thing to watch! If you know me at all you know I L-O-V-E love dachshunds and everything about them! These races are so funny because these little guys are so excited at the starting line. They are so wound up to get going on that race and for what? To get a squeaky ball!? Not much of a prize as far as you and I are concerned… (or Zuckie – one of my dachshunds – for that matter. He does not like anything that squeaks! He doesn’t like noise… loud trucks, loud anything and especially sirens).
24 Do you not know that those who run in a race all run, but one receives the prize? Run in such a way that you may obtain it. 25 And everyone who competes for the prize is temperate in all things. Now they do it to obtain a perishable crown, but we for an imperishable crown. 26 Therefore I run thus: not with uncertainty. Th us I fight: not as one who beats the air. 27 But I discipline my body and bring it into subjection, lest, when I have preached to others, I myself should become disqualified.
We should be running for the prize daily! So shouldn’t we begin our daily race the way these little dachshunds begin their race? With excitement, anticipation and readiness? We as Christians, in our walk with the Lord, should be filled with excitement, anticipation and readiness. If we meet every day with that frame of mind we cannot loose!
Jesus left us a Helper which is the Holy Spirit, our closest friend! That means He can help us throughout each day! I have a friend at work that when she gets there and walks to her desk we speak the “Good Mornings”. Then we ask one another the usual “how are you doing?” We usually say…”Blessed and Highly Favored!” and yesterday I added “…because I am a child of the King!” If we truly believe this we can meet each day with an attitude of excitement for what God will do in our lives that day, anticipation of how it will change us or someone around us and readiness to be used for the Kingdom of Christ.
He has blessed you with another day to breathe the air of freedom we have here in America – and that is so precious and hard to come by to others throughout the world.
Therefore, thank Him for all the blessings you have whether it be a little heartbeat at your feet (human or animal) or a job, or a vehicle to drive, or a nice soft (or firm) bed to sleep in, or food on your table or any number of things! You choose! Focus on what blessings God has bestowed on you in your life and not the worries, problems and trials you face each day and THANK HIM FOR THOSE BLESSINGS! I know… I KNOW if you do this you will feel better and you will be ready to run the race for the day!
The Song – Hezekiah Walker – Every Praise!
WE ARE RUNNING THE RACE FOR LIFE!
I am re-posting an older post. I haven’t had enough time to research and read about Moses, yet. Please enjoy this one about running a race. I have begun reading a book “Unstoppable” by Christine Caine. I have just begun the book, but this post is about a race that we run every day and so is the book.
I will be back to writing about Moses tomorrow! Thanks for your patience. Enjoy!
24 Do you not know that those who run in a race all run, but one receives the prize? Run in such a way that you may obtain it. 25 And everyone who competes for the prize is temperate in all things. Now they do it to obtain a perishable crown, but we for an imperishable crown. 26 Therefore I run thus: not with uncertainty. Thus I fight: not as one who beats the air. 27 But I discipline my body and bring it into subjection, lest, when I have preached to others, I myself should become disqualified.
We should be running for the prize daily! So shouldn’t we begin our daily race the way these little dachshunds begin their race? With excitement, anticipation and readiness? We as Christians, in our walk with the Lord, should be filled with excitement, anticipation and readiness. If we meet every day with that frame of mind we cannot loose! Jesus left us a Helper which is the Holy Spirit, our closest friend! That means He can help us throughout each day! I have a friend at work that when she gets there and walks to her desk we speak the “Good Mornings” and then we ask one another the usual “how are you doing?” We usually say…”Blessed and Highly Favored!” and yesterday I added “…because I am a child of the King!” If we truly believe this we can meet each day with an attitude of excitement for what God will do in our lives that day, anticipation of how it will change us or someone around us and readiness to be used for the Kingdom of Christ.
He has blessed you with another day to breathe the air of freedom we have here in America – that is so precious and hard to come by to others throughout the world. You can thank Him for all the blessings you have whether it be a little heartbeat at your feet (human or animal) or a job, or a vehicle to drive, or a nice soft (or firm) bed to sleep in, or food on your table or any number of things! You choose! Focus on what blessings God has bestowed on you in your life and not the worries, problems and trials you face each day and THANK HIM FOR THOSE BLESSINGS! I know… I KNOW if you do this you will feel better and you will be ready to run the race for the day!
The Video – Hezekiah Walker – Every Praise!
But let’s focus on how the dachshunds begin the race. These little guys are so excited and so ready to get going! Excitement, anticipation and readiness are the traits you see in them! They are full of joy and life! You know we run a race too! Every day! And we run the race for a far greater prize than any squeaky ball. We are running for the prize of an imperishable crown (1 Corinthians 9:24-27). We should be running for the prize daily! So shouldn’t we begin our daily race the way these little dachshunds begin their race? With excitement, anticipation and readiness? We as Christians, in our walk with the Lord, should be filled with excitement, anticipation and readiness. If we meet every day with that frame of mind we cannot loose! Jesus left us a Helper which is the Holy Spirit, our closest friend! That means He can help us throughout each day! I have a friend at work that when she gets there and walks to her desk we speak the “Good Mornings” and then we ask one another the usual “how are you doing?” We usually say…”Blessed and Highly Favored!” and yesterday I added “…because I am a child of the King!” If we truly believe this we can meet each day with an attitude of excitement for what God will do in our lives that day, anticipation of how it will change us or someone around us and readiness to be used for the Kingdom of Christ. | http://abidinginthevine.net/tag/run-the-race/ |
COVID has been particularly cruel to segments of the population, including minorities, nursing home residents and the disabled.
As the COVID-19 pandemic continues to spread across the globe, young people with disabilities are facing unique challenges. The threat of contracting the virus has led to schools and businesses closing, citizens being told to stay home and shelter in place and hospitals being overrun.
Emerging research on COVID-19 shows that the coronavirus pandemic has increased psychological distress both in the general population and among high-risk groups. Behaviors such as physical distancing, as well as their social and economic impacts, are worsening mental health consequences. Research on the psychological impact of mass trauma (e.g., natural disasters, flu outbreaks) suggests that the pandemic might particularly harm the mental health of marginalized populations who have less access to socioeconomic resources and supportive social networks.
There are unique stressors and challenges that could worsen mental health for people with disabilities during the COVID-19 crisis.
Sickcare USA, Inc has been lax in addressing behavioral health, social determinants and those with disabilities, which have been amplified by the COVID pandemic.
The collision of media, information and communications technologies (MICT) and BIG DIGITAL might be a solution for sickcare, workforce development and education.
Cabled not Disabled is a new reality. But, unlike a vaccine, those with disabilities will still be at risk in the post-COVID 4th industrial revolution. Making it happen will require a new global cybernervous system, education and training, universal broadband access, different customer service requirements and innovative business models.
Creating a better diabled customer experience will mean MICTurating on it, much like PISSing on doctor burnout. | https://sopenet.org/cabled-not-disabled/ |
It should be noted that, while weak to one type of damage after every TP move, it is resistant to all other types. For example, after using Seismic Impact it will take increased damage from piercing, but will resist all other types of damage until the next TP move. Striking with the type of attack it is currently weak to does approximately 1.5x damage, while resisted attacks do approximately 0.5x damage.
|Physical Qualities||Magical Qualities|
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Every attack is considered a TP attack. To strike "!!" weaknesses, attacks must be carefully timed in between its own attacks.
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|Further Notes|
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(see testimonials)
This article uses material from the "Ironclad_Smiter" article on FFXIclopedia and is licensed under the CC-BY-SA License. | https://ffxi.gamerescape.com/wiki/Ironclad_Smiter |
How long is a 7 page essay?
Using this as an example, a 3-4 page double spaced paper is 750-1000 words, and a 7 page double spaced paper would be 1750 words. Assignments often specify a research paper or essay length in terms of words, rather than pages – a paper of 750-1000 words or a paper of 1500-1750 words.
Can you write a 10 page paper in one day?
It is certainly quite possible to write a 10 page paper in a day, or even a considerably longer paper in a day. The first step is to GET OFF QUORA and all other social media until you are finished with your project, and avoid all distractions.
How many paragraphs is a 10 page paper?
But be sure to break the subject matter into smaller sections with each section carrying a detailed analysis of the topic sentence. The entire research paper 10 pages may contain approximately 22 paragraphs. The research paper will naturally begin with an introduction that may consist of two paragraphs.
How do you write a 10 page essay?
Use a Timeline
- Fully understand the assignment and ask any questions.
- Start to read and document sources.
- Create notecards and cite books for sources.
- Write a summary of what you’ve discovered so far that will be used in some of your paper.
- Create 3-5 subtopics and outline points you want to explore.
Can I finish a 7 page essay in one day?
Definitely possible. I’ve done it before during my senior year of college since I had so much work to do. Do one page per hour and then take a small break — then do the next page and take another break; repeat until the essay is done.
Can I write a 10 page paper in 5 hours?
If you’re a slow, hesitant writer, an hour per page is the maximum I would ever suggest. In all likelihood, you can probably write a fairly decent 10 to 12-page paper in about five hours. Set a paced schedule for yourself and then work carefully but briskly.
How long will it take to write a 10 page paper?
Writing 10 pages will take about 2.1 hours for the average writer typing on a keyboard and 4.2 hours for handwriting. However, if the content needs to include in-depth research, links, citations, or graphics such as for a blog article or high school essay, the length can grow to 16.7 hours.
Can I write 7 pages in a day?
Can I write a 10-page paper in 5 hours?
How many words are in a 10 page essay?
It seems like a good length for most topics that instructors want students to research and write about. Plus, it doesn’t seem horribly discouraging – in terms of how many words is a ten page paper double spaced, it will vary from about 2500 – 2750.
How to write a 10 page paper well?
How to write a ten page paper well means that you sift through your research and identify the major sections that you will want to cover. These sections will let you get organized for writing, whether you choose to make an outline or not. At least, put the sub-topics in a logical order so that the paper will flow well.
Can a student write a 10 page research paper?
Students who have to write 10 page research paper may often experience problems relating to selection of the topic of the research paper essay. It includes practical research work and then writing the paper in a proper formatting style as per the requirements of the particular academic standards.
How many sources do you need for a 10 page essay?
Part of learning how to write a 10 page essay is knowing what resources to use and how many sources for a 10 page paper is enough. Generally, six resources should be a minimum, although there really is no maximum limit. Be aware that some professors limit the number of online sources you can use. | https://www.cravencountryjamboree.com/other/how-long-is-a-7-page-essay/ |
Liter (abbreviations: ltr, or lit, or l, or litre): is an SI accepted metric system unit of volume equal to 1 cubic decimetre (dm3), 1,000 cubic centimetres (cm3) or 1/1,000 cubic metre. A cubic decimetre (or litre) occupies a volume of 10x10x10 centimetres and is thus equal to one-thousandth of a cubic metre.
Centimeter Cube (abbreviations: cm3, or cm cube): is the SI derived unit of volume. It is the volume of a cube with edges one centimeter in length.
How to Convert Liters to Centimeters Cube
Example: How many centimeters cube are equivalent to 91.26 liters?
As;
1 liters = 1000 centimeters cube
91.26 liters = Y centimeters cube
Assuming Y is the answer, and by criss-cross principle;
Y equals 91.26 times 1000 over 1
(i.e.) Y = 91.26 * 1000 / 1 = 91260 centimeters cube
Answer is: 91260 centimeters cube are equivalent to 91.26 liters.
Practice Question: Convert the following units into cm3:
N.B.: After working out the answer to each of the next questions, click adjacent button to see the correct answer. | https://www.infoapper.com/unit-converter/volume/l-to-cm3/ |
Polygons always give a shiver to most students but you don’t need to be afraid of it. Polygon is no scary topic, in fact it is a really interesting and fun topic. Therefore this topic from the GRE Quantitative Reasoning section can be easily mastered by understanding the fundamental points and practicing problems.
Let us understand What polygons are and What its concepts are?
Any two-dimensional figure made up of three or more straight sides are known as polygons. The naming of the polygons is done according to the number of sides they are made of.
|Name of Polygon||Number of sides|
|Triangle||3|
|Quadrilateral||4|
|Pentagon||5|
|Hexagon||6|
|Heptagon||7|
|Octagon||8|
|Nonagon||9|
|Decagon||10|
|Do-decagon||12|
|n-gon||n|
Properties of Polygons
- The sum of all the interior angles of a polygon having n- number of sides (n – 2)×180°. For example, the summation of the interior angles of a do-decagon will be :
(12 – 2) × 180°= 10 × (180°) = 1800°.
- Any polygon that has equal interior angles and equal sides is known as a regular polygon.
- The perimeter of a polygon = Summation of all the sides of the polygon
- The total sum of the exterior angles of any polygon = 360°.
- The area of a polygon = The region bounded by the polygon. Each polygon figure has different formulas specified for calculating their area.
Characteristics of Polygons
- Triangles: This is the simplest form of polygon having only three sides. Properties of triangle:
- The summation of the two sides of a triangle is always greater than the third side. Similarly, the difference of two sides is always less than the third side.
- The greater is the angle of a triangle, the greater will be its corresponding side.
- The sum of the internal angles of a triangle is always supplementary.
- There are many types of triangles, namely; equilateral, isosceles, scalene, acute angle triangle, obtuse angled triangle, right angled triangle.
- The sum of angles in the triangle is 180 degrees.
- Quadrilaterals: Quadrilaterals are made up of four straight sides.
- There are mainly six types of quadrilaterals, namely; square, rectangle, kite, parallelogram, trapezium and rhombus.
- A parallelogram is a type of quadrilateral where the opposite sides are parallel and congruent. The diagonals of a parallelogram bisects each other.The area of a parallelogram is the product of base and height.
- A parallelogram with only one set of parallel sides is known as a trapezium. The area of a trapezium is the average length of the parallel sides multiplied by height.
- Sum of internal angles as well as external angles of a quadrilateral is always equal to 360o.
- Pentagon: Five straight sides together make up a pentagon
- The summation of the internal side of a pentagon is equal to 540o
- The angle made at the center of a regular pentagon formed by each side = 360o÷5 = 72o.
- Every individual interior angle of a regular pentagon = 108o
- There are two types of polygons, namely; regular and irregular. Curved shapes are not polygons.
- A regular polygon has equal length sides and equal angles between each side.
- An irregular polygon has unequal length sides and unequal angles between sides.
The polygons usually tested in the GRE exam are triangles and quadrilaterals. The quadrilaterals that are highly liked by GRE question makers are: Parallelograms, Squares, Rectangles and Kites.
BYJU’S will be glad to help you in your GRE preparation journey. You can ask for any assistance related to GRE from us by just giving a missed call at +918884544444, or you can drop an SMS. You can write to us at [email protected]. | https://byjus.com/free-gre-prep/polygons/ |
Q:
Constructing regular integer matrices with distinct integer eigenvalues
How can I construct matrices with positive integer values and distinct integer
eigenvalues (not necessarily positive, but 0 should not be an eigenvalue). The
standard-method to construct matrices with given eigenvalues is a transformation
$A\rightarrow B^{-1}AB$, but the problem is that such transformations do not tend to
produce positive matrices. A few examples are (the eigenvalues are shown in brackets)
$[4, 2; 3, 5] \ \ \ \ [2, 7]~$
$[2, 5, 2; 5, 2, 6; 6, 6, 5] \ \ \ [-3, -1, 13]~$
$[1, 5, 4, 3; 4, 6, 1, 2; 5, 1, 4, 3; 2, 5, 4, 2] \ \ \ [-3, -1, 4, 13]~$
$[1, 1, 5, 3, 5; 4, 6, 3, 4, 5; 6, 6, 5, 5, 4; 6, 3, 5, 5, 4; 5, 6, 4, 5, 4] $
$[-3, -1, 1, 2, 22]~$
I do not know a 6x6-matrix or a bigger one with the desired property.
A:
For a $6 \times 6$ example, try
$$ \left[ \begin {array}{cccccc} 6&1&1&1&1&1\\ 1&6&1&1
&1&1\\ 1&2&5&1&1&1\\ 1&2&2&3&1&2
\\ 1&2&2&1&3&2\\ 1&2&2&1&2&3
\end {array} \right]
$$
with eigenvalues $1,2,3,4,5,11$.
EDIT: More generally, start with an $n \times n$ diagonal matrix $D$ with positive integer diagonal entries
$d_1 > d_2 > \ldots > d_n$. Let $B$ be the $n \times n$ matrix with first row
$[d_1, d_2, \ldots, d_n$ and all else $0$. Thus $B + D$ is upper triangular
with eigenvalues $2 d_1, d_2, \ldots d_n$ which are distinct positive integers.
Take $A = L (B + D) L^{-1}$ where $L$ is the lower triangular matrix with
all entries $1$ on and below the main diagonal. Of course, this has the same eigenvalues as $B+D$. Note that $L^{-1}$ has
$1$ on the main diagonal, $-1$ on the diagonal below that, and everything else $0$. Then
$$A_{ij} = \cases{d_j - d_{j+1} & if $ i < j < n$\cr
2 d_j - d_{j+1} & if $ i = j < n$\cr
2 d_j - 2 d_{j+1} & if $i > j$\cr
d_n & if $i < j = n$\cr
2 d_n & if $i=j=n$\cr
}$$
which are all positive integers.
EDIT: Still more generally, you don't need to use the same positive integers in $B$ and $D$...
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Q:
let R be an ordering of Aand S be the coresponding strict ordering of A, and R* be the ordering coresponding to S show R=R*
i think i have to use these facts
(a,b)$\in$R* and a$\neq$b
(a,b)$\in$R or a=b
to show they are both subsets of each other .?? but im not sure how.
A:
If I understand your question correctly, you have a relation $R$ on $A$ that is reflexive, antisymmetric, and transitive, $S=\{\langle a,b\rangle\in R:a\ne b\}$ is the strict order corresponding to $R$, and $R^*$ is the non-strict order extending $S$, and you want to prove that $R^*=R$.
By definition $R^*=S\cup\{\langle a,a\rangle:a\in A\}$, so you’re trying to show that
$$\{\langle a,b\rangle\in R:a\ne b\}\cup\{\langle a,a\rangle:a\in A\}=R\;.$$
You can indeed do this by showing that each of the sets $\{\langle a,b\rangle\in R:a\ne b\}\cup\{\langle a,a\rangle:a\in A\}$ and $R$ is a subset of the other. I’ll do one direction.
If $\langle x,y\rangle\in\{\langle a,b\rangle\in R:a\ne b\}\cup\{\langle a,a\rangle:a\in A\}$, then either $\langle x,y\rangle\in\{\langle a,b\rangle\in R:a\ne b\}$, or $\langle x,y\rangle\in\{\langle a,a\rangle:a\in A\}$. If $\langle x,y\rangle\in\{\langle a,b\rangle\in R:a\ne b\}$, then certainly $\langle x,y\rangle\in R$. If, on the other hand, $\langle x,y\rangle\in\{\langle a,a\rangle:a\in A\}$, then $\langle x,y\rangle=\langle a,a\rangle$ for some $a\in A$, and then $\langle x,y\rangle\in R$ because $R$ is reflexive.
Now you show that $R\subseteq\{\langle a,b\rangle\in R:a\ne b\}\cup\{\langle a,a\rangle:a\in A\}$: assume that $\langle x,y\rangle\in R$, and show that either $\langle x,y\rangle\in\{\langle a,b\rangle\in R:a\ne b\}$, or $\langle x,y\rangle\in\{\langle a,a\rangle:a\in A\}$.
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Centrifuges for Paper Mill Waste Sludge Dewatering W. C. MATTHEWS, Senior Staff Consultant GEORGE H. ANDREWS, Technical Director Central Research Laboratory The Mead Corporation Chillicothe, Ohio JOHN K. SULLINS, Technical Director Kingsport Division The Mead Corporation Kingsport, Tennessee INTRODUCTION The use of centrifuges in the paper industry has had a long history of successful operation in the concentration of solids materials in the papermaking operations. Mead and others have used centrifuges for the recovery of lime from the water softening process. In the Chillicothe Division of Mead, this has resulted in the recovery and reuse of 20 to 25. tons of material each day that previously was discharged to the stream. In a cooperative study (1) carried out in 1958 and 1959 by the Ohio Mills Research Group and the National Council For Stream Improvement on the sludge de- watering of paper mill wastes, it was indicated that the use of centrifuges for the concentration of sludges from the clarification of paper mill effluent nad much promise. At approximately this same time, technological improvements were being made in the design of centrifuges with the higher "G" forces and greater load capacities that made the use of this equipment more feasible than had previously been the case. As an outgrowth of these studies, centrifuges were installed in three mills in the Miami Valley in Ohio, and the results from these operations have been described in a paper presented by Bamford (2). Since that time, the number of centrifuges in the industry has increased many times so that there are now some 27 installations using a total of 34 centrifuges for the concentration of sludges resulting from the clarification of paper mill effluents. There are now more than 30 plants using centrifuges for the concentration of lime mud, and four installations using such units for the recovery of lime from water softening sludges. The two main types of centrifuges of interest are the solid bowl conveyor type and the disk centrifuge with nozzle discharge. It is the solid bowl type that has found extensive use in the paper industry, since up to the present time our main concern has been with primary treatment. As we become involved with secondary treatment, where a higher centrifugal force is needed, the disk type may be of increasing importance. The solid-bowl horizontal-conveyor type centrifuge is available in different gravitational forces. A sketch of one such unit, capable of operating up to 3200 'G" force is shown in Figure 1. This unit has a solid cylindrical bowl supported - 325 -
Object Description
|Purdue Identification Number||ETRIWC196729|
|Title||Centrifuges for paper mill waste sludge dewatering|
|Author||
Matthews, W. C.
|
Andrews, George H.
Sullins, John K. | http://e-archives.lib.purdue.edu/cdm/compoundobject/collection/engext/id/14567/rec/34 |
Mathematics Exam Advice
- The first piece of advice is to read questions carefully. Don’t glance at a question and go off writing: take a moment to understand what you have been asked to do.
- Don’t use tippex; instead draw a simple line(s) through work that you think is incorrect.
- For equations, check your solution by substituting your solution into the original equation. If your answer is wrong and you know it is wrong: write that on your script.
If you do have time at the end of the exam, go through each of your answers and ask yourself:
- have I answered the question that was asked?
- does my answer make sense?
- check your answer (e.g. differentiate/antidifferentiate an antiderivative/derivative, substitute your solution into equations, check your answer against a rough estimate, or what a picture is telling you, etc)
Week 12
On Monday, and Wednesday PM, we finished the module by looking at triple integrals.
The Wednesday 09:00 lecture was a tutorial along with most of Wednesday PM and the Thursday class.
Week 13
Monday is a bank holiday.
In the Wednesday 09:00 lecture we will work on the Summer 2018 Paper and hopefully finish it before the end of the Thursday 10:00 lecture.
If we finish the Summer 2018 paper early (unlikely), any extra time will be dedicated to one-to-one help.
Exam Papers
These are not always found in your programme selection — most of the time you will have to look here.
Study
Please feel free to ask me questions about the exercises via email or even better on this webpage.
Student Resources
Please see the Student Resources tab on the top of this page for information on the Academic Learning Centre, etc.. | https://jpmccarthymaths.com/2019/05/01/math7021-spring-2019-week-12/ |
Why Does My Cat Follow Me Everywhere?
Are you wondering why your furry friend just won’t leave you alone? Does your cat follow you around the house, from room to room, as if she’s almost glued to your hip? Though it may feel a bit strange at times, there could be a few reasons why your kitty is paying so much attention to her favorite human.
Cats are surprisingly social creatures and their attentiveness to us can be incredibly rewarding or extremely annoying depending on the situation. In this blog post, we’ll take an in-depth look at some of the possible explanations for why does my cat follow me everywhere.
There are many theories behind this mysterious behavior, and it’s important to understand so that we can appreciate our cats even more. Cats have been domesticated for centuries, yet their behavior still remains largely unknown to us.
Ever since you brought your furry feline home, they have been a loyal companion who follows you everywhere— from room to room in your house and even out into the yard. While it’s endearing that your cat loves being so close to their favorite person, you may be wondering why does my cat follow me everywhere?
After all, cats are known for having minds of their own and keeping a certain distance when they choose. Turns out there is quite an interesting psychology behind cats following humans around the house or outdoors.
Why Does My Cat Follow Me Everywhere?
The most likely explanation for why cats follow their humans is because of the bond they have created with them. Cats are very social animals, and they view the members of their human family as part of their own “clan” or group. In other words, your cat may be following you around simply because she loves spending time with you and wants to be close to you.
Cats can become very attached to their owners, so if your cat follows you around it could be because she’s trying to show her affection for you. Cats may also follow their people as a way of reassuring themselves that everything is okay—they want to make sure their person is safe and sound.
In addition to the bond cats form with their humans, there could also be some practical reasons why cats follow us around. For instance, cats are natural hunters and like to stay close to their people to detect any potential prey in the environment. By staying near you, your cat is likely on the hunt for small critters or reptiles that she can stalk and catch.
Your cat may also be looking for food or attention from you. Cats are creatures of habit, so if they see you doing something that involves food or petting, they may try to follow you around in hopes of getting some treats or a good cuddle session!
Finally, cats may also follow us around simply because they are curious creatures. They want to explore their environment and see what’s going on—and who better to do that with than their favorite person? Your cat may be just following you out of sheer curiosity and a need to stay close to their beloved human companion.
So, why does my cat follow me everywhere? The answer is simple—because cats are social animals that form strong bonds with their humans and because of the practical reasons mentioned above. Whatever the reason may be, we can all agree that it’s pretty special when our cats follow us around. After all, it’s a sign that they love us and view us as part of their family!
Do All Cats Follow Their Owners Around?
Not all cats will follow their owners around. Some cats are more independent and content to stay in one area of the home, while other cats will be more social and like to be around their owners. It really depends on the individual cat’s personality and preferences. However, if you have a particularly sociable kitty, it can be endearing when they follow you around. Just make sure that your feline friend isn’t getting too stressed by it and has plenty of places to retreat if they need some peace and quiet. As long as your cat is comfortable, it can be a sweet experience to share with them.
If your cat does decide to follow you around, it is likely because they are comfortable and feel secure in their environment. It can also be a sign that they enjoy your company and want to spend as much time with you as possible. Cats love being interactive and engaging with their owners, so this could be an indication of how content they are in your home.
Overall, the decision to follow the owner around is up to each individual cat. If your cat enjoys following you, then it can add a special bond between you and create some memorable moments. Just make sure that your cat isn’t feeling stressed or overwhelmed by being too close. Happy cats make for happy owners!
How Can I Get My Cat to Stop Following Me Around?
If your cat is following you too closely or getting in the way of daily activities, there are a few things you can do. First, make sure that your cat has plenty of toys and other objects to keep her occupied while you’re away from home or busy doing something else. This will help distract them and give them something to focus on other than following you around.
You can also try to establish certain areas in the house that are off-limits for your cat. This will give them a space where they can retreat and relax without feeling like they have to follow you everywhere. Make sure that these spaces are comfortable and appealing, so your cat is happy to stay there.
If simply giving your cat attention doesn’t work, consider providing it with more stimulation while you are away. Set up an area with toys, scratching posts, and other objects that your cat can explore while you are out of the house. You may even want to consider getting another cat or pet as a companion for your feline friend. The presence of another animal may help keep it occupied when you’re not around.
Finally, rewarding your cat when they aren’t following you can help encourage this behavior. If they don’t follow you around the house, give them a treat or some extra cuddles to let them know that it is appreciated and encouraged.
Overall, cats may follow their owners around for various reasons. It could be out of curiosity, comfort, or affection—or some combination of the three. If your cat follows you around, it can be a sign of their deep bond and connection with you. However, if your cat’s following is becoming too much for you to handle, there are ways to help them break this habit and find other activities to do. No matter why your cat follows you around, it’s a reminder of how special the bond between cats and humans can be. Enjoy these precious moments with your feline friend!
FAQs of Why Does My Cat Follow Me Everywhere
Why does my cat follow me to the bathroom?
It is common for cats to follow their owners to the bathroom. This behavior is often due to your cat’s strong bond with you. Cats are very curious and love to explore, so they may want to investigate what you’re doing in the bathroom. Additionally, cats tend to be quite territorial and protective of their owners, so they may want to be present in case you need help or protection. Finally, cats may simply enjoy your company and want to spend time with you, even if it’s just a short trip to the bathroom. Whatever the reason for your cat following you to the bathroom, it is likely that they are displaying their affection towards you. Enjoy the special bond!
How do you tell if a cat loves you?
Cats are often mysterious and hard to read, but with a little patience and observance you can tell if your cat loves you. Here are some signs that your cat may love you:
– Your cat will show affection by rubbing against you or leaning into your hand as you pet them.
– They will purr when they’re around you, which is a sign of contentment.
– Your cat will make eye contact with you and follow you around the house with their eyes.
– They will greet you at the door when you come home from work or school, or even when leaving for short errands.
– They may bring you their favorite toys as a sign of affection.
– Your cat will sleep next to you, or in your lap if they’re feeling particularly loving.
– They may give you gifts such as dead mice or other small critters.
These are just some of the ways that cats show their love, but each cat is unique and may have their own way of expressing affection. It’s important to take the time to get to know your feline friend so you can understand how they communicate with you. If you observe these signs, then there’s a good chance your cat really loves you!
What is the most affectionate cat breed?
The most affectionate cat breed is the Ragdoll. This breed is known for its extremely loving and laid-back personality, making them a great choice for families looking for a friendly and cuddly pet. Ragdolls tend to be very loyal to their owners, and enjoy spending time with them. They also have a very gentle and calm temperament, making them well-suited to both young and old owners alike.
Another breed known for its affectionate nature is the Persian. Persians are well known for their sweet and gentle personalities, making them perfect companions for people who want a loyal and loving pet. They tend to be quite laid-back and calm, but can also be playful when they want to. Additionally, Persians enjoy receiving love from their owners and showing them plenty of affection in return. They make excellent cuddle buddies and can even learn to respond to simple commands with a little bit of patience and effort. All in all, Persians are some of the most affectionate cats around, so if you’re looking for an extra loving companion, this breed is definitely worth considering.
Do cats have a favorite person to sleep with?
Yes, cats do have a favorite person to sleep with. Cats are very social animals and can form strong bonds with their owners. They will often choose to sleep on you or next to you over any other place in the house. Cats may even recognize specific people’s smells and prefer sleeping near that individual over others.
Additionally, cats may choose to sleep with their favorite person because they feel safe and secure around them. Cats prefer a comfortable, warm space so they may also be looking for a cozy spot to curl up in when they find their favorite person. Generally speaking, cats will seek out the company of those they trust most and want to spend time with!
Do cats trust you if they sleep around you?
Yes, cats can certainly trust the people they sleep around. Cats are very sensitive creatures that rely heavily on their sense of smell to assess and evaluate their environment and the people in it.
If a cat feels safe and comfortable around you, he or she may choose to curl up near you for a nap. This is an indication that your cat trusts you and looks to you for safety and protection. In order to ensure that your cat feels this level of trust around you, it is important to develop a positive relationship with them by providing consistent care, attention, and affection.
This can be done through spending quality time together, engaging in interactive playtime activities, grooming your cat regularly, and simply providing a warm and comfortable place to sleep. If you follow these steps, your cat will be sure to trust you and feel safe around you.
Why does my cat follow me in heat?
When your cat is in heat, her hormones are surging and she’s feeling extra loving and affectionate. This is why cats will often follow their owners around during this time—they’re looking for comfort, reassurance, love, and attention from the person they trust most. Your cat may want to be close to you because you make her feel safe and secure. She may also be trying to get your attention so she can show her affection and let you know she needs a bit of extra care right now.
Why does my cat follow me when I wake up?
Cats are naturally curious creatures and when they notice that you’re awake and up and about, they will be drawn to your movements. It could also be that they have gotten used to being fed at certain times of the day and so when you wake up, they know it’s time for breakfast or dinner!
It’s also possible that cats may be drawn to you for comfort and companionship. Cats are intelligent creatures who form strong bond with their caretakers, so it’s only natural that they would want to stay close and be near the person they trust.
Finally, cats may just simply enjoy human company! They love getting attention from their owners and may follow you around just to be close. So your cat’s morning wake-up routine could simply be a sign of its affection for you!
Conclusion
In conclusion, the reasons why cats follow their owners everywhere is because of the bond that has been created between the two. Cats recognize their owners as a source of comfort, safety, and attention. When cats are around their owners, they feel protected from danger and safe from harm. They also want to be part of their owner’s day-to-day activities.
By following their owners around, cats can be close to them and get the attention they crave. Cats are also very curious animals, so they want to explore the environments around them and experience something new. Ultimately, cats demonstrate their love for their owners by following them everywhere!
We hope this post has helped answer the question, ‘why does my cat follow me everywhere?’. Understanding why cats behave in certain ways can help you become a better cat owner and develop an even stronger bond with your furry friend! Thanks for reading and feel free to comment below if you have any other questions about cats or their behavior. | https://vetranch.org/blog/why-does-my-cat-follow-me-everywhere/ |
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Computational chemistry
Computational chemistry is a branch of chemistry that uses computers to assist in solving chemical problems. It uses the results of theoretical chemistry, incorporated into efficient computer programs, to calculate the structures and properties of molecules and solids. While its results normally complement the information obtained by chemical experiments, it can in some cases predict hitherto unobserved chemical phenomena. It is widely used in the design of new drugs and materials.
Examples of such properties are structure (i.e. the expected positions of the constituent atoms), absolute and relative (interaction) energies, electronic charge distributions, dipoles and higher multipole moments, vibrational frequencies, reactivity or other spectroscopic quantities, and cross sections for collision with other particles.
The methods employed cover both static and dynamic situations. In all cases the computer time increases rapidly with the size of the system being studied. That system can be a single molecule, a group of molecules or a solid. The methods are thus based on theories which range from highly accurate, but are suitable only for small systems, to very approximate, but suitable for very large systems. The accurate methods used are called ab initio methods, as they are based entirely on theory from first principles. The less accurate methods are called empirical or semi-empirical because some experimental results, often from atoms or related molecules, are used along with the theory.
Additional recommended knowledge
History
Building on the founding discoveries and theories in the history of quantum mechanics, the first theoretical calculations in chemistry were those of Walter Heitler and Fritz London in 1927. The books that were influential in the early development of computational quantum chemistry include: Linus Pauling and E. Bright Wilson’s 1935 Introduction to Quantum Mechanics – with Applications to Chemistry, Eyring, Walter and Kimball's 1944 Quantum Chemistry, Heitler’s 1945 Elementary Wave Mechanics – with Applications to Quantum Chemistry, and later Coulson's 1952 textbook Valence, each of which served as primary references for chemists in the decades to follow.
With the development of efficient computer technology in the 1940s the solutions of elaborate wave equations for complex atomic systems began to be a realizable objective. In the early 1950s, the first semi-empirical atomic orbital calculations were carried out. Theoretical chemists became extensive users of the early digital computers. A very detailed account of such use in the United Kingdom is given by Smith and Sutcliffe. The first ab initio Hartree-Fock calculations on diatomic molecules were carried out in 1956 at MIT using a basis set of Slater orbitals. For diatomic molecules a systematic study using a minimum basis set and the first calculation with a larger basis set were published by Ransil and Nesbet respectively in 1960. The first polyatomic calculations using Gaussian orbitals were carried out in the late 1950s. The first configuration interaction calculations were carried out in Cambridge on the EDSAC computer in the 1950s using Gaussian orbitals by Boys and coworkers. By 1971, when a bibliography of ab initio calculations was published, the largest molecules included were naphthalene and azulene. Abstracts of many earlier developments in ab initio theory have been published by Schaefer.
In 1964, Hückel method calculations, which are a simple LCAO method for the determination of electron energies of molecular orbitals of π electrons in conjugated hydrocarbon systems, ranging from simple systems such as butadiene and benzene to ovalene with 10 fused six-membered rings , were generated on computers at Berkeley and Oxford. These empirical methods were replaced in the 1960s by semi-empirical methods such as CNDO.
In the early 1970s, efficient ab initio computer programs such as ATMOL, GAUSSIAN, IBMOL, and POLYAYTOM, began to be used to speed up ab initio calculations of molecular orbitals. Of these four programs only GAUSSIAN, massively expanded, is still in use, but many other programs are now in use. At the same time, the methods of molecular mechanics, such as MM2, were developed, primarily by Norman Allinger.
One of the first mentions of the term “computational chemistry” can be found in the 1970 book Computers and Their Role in the Physical Sciences by Sidney Fernbach and Abraham Haskell Taub, where they state “It seems, therefore, that 'computational chemistry' can finally be more and more of a reality.” During the 1970s, widely different methods began to be seen as part of a new emerging discipline of computational chemistry. The Journal of Computational Chemistry was first published in 1980.
Concepts
The term theoretical chemistry may be defined as a mathematical description of chemistry, whereas computational chemistry is usually used when a mathematical method is sufficiently well developed that it can be automated for implementation on a computer. Note that the words exact and perfect do not appear here, as very few aspects of chemistry can be computed exactly. Almost every aspect of chemistry, however, can be described in a qualitative or approximate quantitative computational scheme.
Molecules consist of nuclei and electrons, so the methods of quantum mechanics apply. Computational chemists often attempt to solve the non-relativistic Schrödinger equation, with relativistic corrections added, although some progress has been made in solving the fully relativistic Schrödinger equation. It is, in principle, possible to solve the Schrödinger equation, in either its time-dependent form or time-independent form as appropriate for the problem in hand, but this in practice is not possible except for very small systems. Therefore, a great number of approximate methods strive to achieve the best trade-off between accuracy and computational cost. Accuracy can always be improved with greater computational cost. Present computational chemistry can routinely accurately calculate the properties of molecules that contain up to about 40 electrons. Errors for energies can be less than 1 kcal/mol. For geometries, bond lengths can be predicted within a few picometres and bond angles within 0.5o. The treatment of larger molecules that contain a few dozen electrons is computationally tractable by approximate methods such as density functional theory (DFT). There is some dispute within the field whether the latter methods are sufficient to describe complex chemical reactions, such as those in biochemistry. Large molecules can be studied by semi-empirical approximate methods. Even larger molecules are treated by classical mechanics methods that are called molecular mechanics.
In theoretical chemistry, chemists, physicists and mathematicians develop algorithms and computer programs to predict atomic and molecular properties and reaction paths for chemical reactions. Computational chemists, in contrast, may simply apply existing computer programs and methodologies to specific chemical questions. There are two different aspects to computational chemistry:
Thus computational chemistry can assist the experimental chemist or it can challenge the experimental chemist to find entirely new chemical objects.
Several major areas may be distinguished within computational chemistry:
Methods
A given molecular formula can represent a number of molecular isomers. Each isomer is a local minimum on the energy surface (called the potential energy surface) created from the total energy (electronic energy plus repulsion energy between the nuclei) as a function of the coordinates of all the nuclei. A stationary point is a geometry such that the derivative of the energy with respect to all displacements of the nuclei is zero. A local (energy) minimum is a stationary point where all such displacements lead to an increase in energy. The local minimum that is lowest is called the global minimum and corresponds to the most stable isomer. If there is one particular coordinate change that leads to a decrease in the total energy in both directions, the stationary point is a transition structure and the coordinate is the reaction coordinate. This process of determining stationary points is called geometry optimization.
The determination of molecular structure by geometry optimization became routine only when efficient methods for calculating the first derivatives of the energy with respect to all atomic coordinates became available. Evaluation of the related second derivatives allows the prediction of vibrational frequencies if harmonic motion is assumed. In some ways more importantly it allows the characterisation of stationary points. The frequencies are related to the eigenvalues of the matrix of second derivatives (the Hessian matrix). If the eigenvalues are all positive, then the frequencies are all real and the stationary point is a local minimum. If one eigenvalue is negative (an imaginary frequency), the stationary point is a transition structure. If more than one eigenvalue is negative the stationary point is a more complex one, and usually of little interest. When found, it is necessary to move the search away from it, if we are looking for local minima and transition structures.
The total energy is determined by approximate solutions of the time-dependent Schrödinger equation, usually with no relativistic terms included, and making use of the Born-Oppenheimer approximation which, based on the much higher velocity of the electrons in comparison with the nuclei, allows the separation of electronic and nuclear motions, and simplifies the Schrödinger equation. This leads to evaluating the total energy as a sum of the electronic energy at fixed nuclei positions plus the repulsion energy of the nuclei. A notable exception are certain approaches called direct quantum chemistry, which treat electrons and nuclei on a common footing. Density functional methods and semi-empirical methods are variants on the major theme. For very large systems the relative total energies can be compared using molecular mechanics. The ways of determining the total energy to predict molecular structures are:
Ab initio methods
The programs used in computational chemistry are based on many different quantum-chemical methods that solve the molecular Schrödinger equation associated with the molecular Hamiltonian. Methods that do not include any empirical or semi-empirical parameters in their equations - being derived directly from theoretical principles, with no inclusion of experimental data - are called ab initio methods. This does not imply that the solution is an exact one; they are all approximate quantum mechanical calculations. It means that a particular approximation is rigorously defined on first principles (quantum theory) and then solved within an error margin that is qualitatively known beforehand. If numerical iterative methods have to be employed, the aim is to iterate until full machine accuracy is obtained (the best that is possible with a finite word length on the computer, and within the mathematical and/or physical approximations made).
The simplest type of ab initio electronic structure calculation is the Hartree-Fock (HF) scheme, an extension of molecular orbital theory, in which the correlated electron-electron repulsion is not specifically taken into account; only its average effect is included in the calculation. As the basis set size is increased the energy and wave function tend to a limit called the Hartree-Fock limit. Many types of calculations, known as post-Hartree-Fock methods, begin with a Hartree-Fock calculation and subsequently correct for electron-electron repulsion, referred to also as electronic correlation. As these methods are pushed to the limit, they approach the exact solution of the non-relativistic Schrödinger equation. In order to obtain exact agreement with experiment, it is necessary to include relativistic and spin orbit terms, both of which are only really important for heavy atoms. In all of these approaches, in addition to the choice of method, it is necessary to choose a basis set. This is a set of functions, usually centered on the different atoms in the molecule, which are used to expand the molecular orbitals with the LCAO ansatz. Ab initio methods need to define a level of theory (the method) and a basis set.
The Hartree-Fock wave function is a single configuration or determinant. In some cases, particularly for bond breaking processes, this is quite inadequate and several configurations need to be used. Here the coefficients of the configurations and the coefficients of the basis functions are optimized together.
The total molecular energy can be evaluated as a function of the molecular geometry, in other words the potential energy surface. Such a surface can be used for reaction dynamics. The stationary points of the surface lead to predictions of different isomers and the transition structures for conversion between isomers, but these can be determined without a full knowledge of the complete surface.
A particularly important objective, called computational thermochemistry, is to calculate thermochemical quantities such as the enthalpy of formation to chemical accuracy. Chemical accuracy is the accuracy required to make realistic chemical predictions and is generally considered to be 1 kcal/mol or 4 kJ/mol. To reach that accuracy in an economic way it is necessary to use a series of post-Hartree-Fock methods and combine the results. These methods are called quantum chemistry composite methods.
Density Functional methods
Density functional theory (DFT) methods are often considered to be ab initio methods for determining the molecular electronic structure, even though many of the most common functionals use parameters derived from empirical data, or from more complex calculations. This means that they could also be called semi-empirical methods. It is best to treat them as a class on their own. In DFT, the total energy is expressed in terms of the total electron density rather than the wave function. In this type of calculation, there is an approximate Hamiltonian and an approximate expression for the total electron density. DFT methods can be very accurate for little computational cost. The drawback is, that unlike ab initio methods, there is no systematic way to improve the methods by improving the form of the functional. Some methods combine the density functional exchange functional with the Hartree-Fock exchange term and are known as hybrid functional methods.
Semi-empirical and empirical methods
Semi-empirical quantum chemistry methods are based on the Hartree-Fock formalism, but make many approximations and obtain some parameters from empirical data. They are very important in computational chemistry for treating large molecules where the full Hartree-Fock method without the approximations is too expensive. The use of empirical parameters appears to allow some inclusion of correlation effects into the methods.
Semi-empirical methods follow what are often called empirical methods where the two-electron part of the Hamiltonian is not explicitly included. For π-electron systems, this was the Hückel method proposed by Erich Hückel, and for all valence electron systems, the Extended Hückel method proposed by Roald Hoffmann.
Molecular mechanics
In many cases, large molecular systems can be modeled successfully while avoiding quantum mechanical calculations entirely. Molecular mechanics simulations, for example, use a single classical expression for the energy of a compound, for instance the harmonic oscillator. All constants appearing in the equations must be obtained beforehand from experimental data or ab initio calculations.
The database of compounds used for parameterization - (the resulting set of parameters and functions is called the force field) - is crucial to the success of molecular mechanics calculations. A force field parameterized against a specific class of molecules, for instance proteins, would be expected to only have any relevance when describing other molecules of the same class.
These methods can be applied to proteins and other large biological molecules, and allow studies of the approach and interaction (docking) of potential drug molecules (eg. and ).
Methods for solids
Computational chemical methods can be applied to solid state physics problems. The electronic structure of a crystal is in general described by a band structure, which defines the energies of electron orbitals for each point in the Brillouin zone. Ab initio and semi-empirical calculations yield orbital energies, therefore they can be applied to band structure calculations. Since it is time-consuming to calculate the energy for a molecule, it is even more time-consuming to calculate them for the entire list of points in the Brillouin zone.
Chemical dynamics
Once the electronic and nuclear variables are separated (within the Born-Oppenheimer representation), in the time-dependent approach, the wave packet corresponding to the nuclear degrees of freedom is propagated via the time evolution operator (physics) associated to the time-dependent Schrödinger equation (for the full molecular Hamiltonian). In the complementary energy-dependent approach, the time-independent Schrödinger equation is solved using the scattering theory formalism. The potential representing the interatomic interaction is given by the potential energy surfaces. In general, the potential energy surfaces are coupled via the vibronic coupling terms.
The most popular methods for propagating the wave packet associated to the molecular geometry are
Molecular dynamics (MD) examines (using Newton's laws of motion) the time-dependent behavior of systems, including vibrations or Brownian motion, using a classical mechanical description. MD combined with density functional theory leads to the Car-Parrinello method.
Interpreting molecular wave functions
The Atoms in Molecules model developed by Richard Bader was developed in order to effectively link the quantum mechanical picture of a molecule, as an electronic wavefunction, to chemically useful older models such as the theory of Lewis pairs and the valence bond model. Bader has demonstrated that these empirically useful models are connected with the topology of the quantum charge density. This method improves on the use of Mulliken population analysis.
Software packages
There are many self-sufficient software packages used by computational chemists. Some include many methods covering a wide range, while others concentrating on a very specific range or even a single method. Details of most of them can be found in: | https://www.chemeurope.com/en/encyclopedia/Computational_chemistry.html |
---
abstract: 'We show that in the grounded conducting sphere image problem, all the necessary informations about the image charge can be found from a mirror equation and a magnification formula. Then, we propose an method to solve the image problem for an extended charge distribution near a grounded conducting sphere.'
address: 'Department of High Energy Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, India'
author:
- Kolahal Bhattacharya
title: 'Analogy of Grounded Conducting Sphere Image Problem with Mirror-Optics'
---
Introduction
============
Image problems in electrostatics refer to boundary-value problems that specify some charge distribution in a volume bounded by a closed surface and also specify the potential on the same surface. However, the problem is constructed such that the potential specified on the surface cannot be due to the known charge distribution only. The problem is, then, to find the general potential function in the volume where the known charge resides. To solve this problem, some other charge distribution outside the boundary is imagined such that at each point on the surface, the potentials due to inside and outside charges sum up to the value specified in the problem. The outside charge is called the image charge. It turns out that in some typical boundary value problems the image method works elegantly: a unique general potential function can be constructed.
For example, let us consider a point charge $q$ at a distance $d$ above an infinite grounded conducting plane. Because the potential must be zero everywhere on this plane, the required potential $\Phi$ above the plane (where $q$ resides), is the same as the sum of the potentials produced by $q$ (above the plane) and an image charge $-q$ placed at a distance $2d$ directly below $q$, inside the plane. Effectively, the image charge is like the optical image of the real charge except for the fact that a plane mirror does not need to be infinite to form optical image. We will try to explore this similarity in this article.
We will start by looking at the grounded conducting sphere problem (Figure 1). A charge $q$ is placed in front of a grounded conducting sphere ($\Phi=0$ on the spherical surface). The potential function at any point $\bf{r}$ in the region where $q$ resides is asked. We apply the image method to solve for the potential function. The image charge effectively replaces the charge induced on the sphere. Thus, $\Phi(\bf{r}) $ can be calculated as if there is no sphere and only the real charge $q$ and image charge $q'$ are there, provided that the position and magnitude of $q'$ are chosen such that $\Phi$ is zero on the surface originally occupied by the sphere. Then, the only job is to find value and position of the image charge. The results are already known and available in the standard texts in References.
A little manipulation of the results will lead to not-so-well-known observations with great similarity with the standard results in geometrical optics. This will put more light on the existing theory of electrostatic images. It will also enable us to handle the image problem of an extended charged body, placed before a grounded conducting sphere. The problem is non- trivial as the image charge is distorted (like optical image produced in a spherical mirror); and hence, the direct calculation of potential function is difficult. The usual approach is to integrate the Green’s function of the generic point charge problem over the volume of the given charge distribution. We propose a more intuitive method that leads to the same formula.
Grounded Conducting Sphere Image Problem
========================================
Standard results of grounded conducting sphere
----------------------------------------------
We consider the grounded conducting sphere image problem (Figure 1). According to reference \[1\], at some field point $\bf{r}$, the potential is the same as that produced by the charge $q$ at $S$ (such that $OS=y$) plus that by the image charge $q'=-\frac{aq}{y}$ placed at $I
$ (so that $OI=y'=\frac{a^2}{y}$). To appreciate the similarity of the present problem with light reflection off a spherical mirror, we first recall the standard results from optics.
Spherical convex mirror in optics
---------------------------------
Light ray emitted from the object at $S$ is reflected off a convex spherical surface (Figure 1) and the image forms at $I$. $F$ is the focus and $O$ is the centre of curvature. Then, we know that the object distance $PS=u$, the image distance $PI=v$, and the focal length $PF=f$ (distance from the pole where image forms if the object is at infinity: $u\rightarrow\infty$) satisfy (with sign convention: $u$ is positive and $v$ and $f$ are negative for convex mirror surface):
$$\frac{1}{u}+\frac{1}{v}=\frac{1}{f}$$
From (2.1), it is seen that the equation remains the same if $v\rightarrow u$ and $u\rightarrow
v$. Thus, according to the principle of reversibility of light path, a real source placed at an object distance $u(<f)$ in front of a $concave$ mirror, has its virtual image formed at a distance $v$ behind the mirror. Therefore, (2.1) is called conjugate foci relationship.
Also, the height of the image $h_{i}$ in terms of the height of the object $h_{o}$ can be calculated from the linear magnification formula: $$|\frac{h_{i}}{h_{o}}|=\ m=\frac{v}{u}$$
Grounded conducting sphere revisited
------------------------------------
### Existence of a mirror formula
Referring to Figure 2, We shift the origin to the point $P$ (Pole), and define $u=y-a$ and $v
=a-\frac{a^2}{y}=\frac{a}{y}(y-a)$. Let us define the $focal \ length$ with respect to pole P as equal to the image charge distance when the real charge is at infinity. Notice that if $ y
\rightarrow\infty$ and hence, $u\rightarrow\infty$, we have $v\rightarrow a$). Therefore, the focal length in the context of the image problem is equal to radius $a$. Then, one can verify the following:
$$\frac{1}{y-a}+\frac{1}{-\frac{a}{y}\ (\ y-\ a)}=\frac{a-y}{a(y-a)}=-\frac{1}{a}$$
where for this convex mirror surface, object charge distance is $u=+(y-a)$ (positive) when image charge distance is $v=-(a-\frac{a^{2}}{y})$ (negative) and the focal distance is $f=-a$ (negative). Thus, like geometrical optics, in image problems (electrostatics) also there exists an analogous mirror equation:
$$\frac{1}{u}+\frac{1}{v}=\frac{1}{f}=\frac{1}{a}$$
### Linear Magnification formula
The value of image charge can be simply found by using linear magnification formula as follows: from the boundary condition that the potentials due to real charge $q$ and the image charge $q'
$ produce sum up to zero at $P$ (Figure 2), we have:
$$\frac{q'}{q}=-\frac{v}{u}=-\frac{a(y-a)}{y(y-a)}=-\frac{a}{y}$$
Thus, $q'=-\frac{aq}{y}$ -which is correct.
Visualization of field lines
============================
We know that an appropriate image charge replaces the charge induced on the surface. In the context of our present problem, how do the resultant electric field lines look like? The answer is provided by Figure 3. The Mathematica plot shows the electric field lines for the charge configuration: $q=2
Q$ and $q'=-Q$, the pole being at the midpoint of $q$ and $q'$. The spherical equipotential surface having $\Phi=0$ appears in place of the spherical surface of grounded conducting sphere. The role of the rays in geometrical optics is played by lines of electric field lines in the sense that these field lines converge to the image charge behind the conducting surface that behaves as a mirror.
Observations
============
Infinite grounded conducting plane image
----------------------------------------
From (2.4), it is seen that in the limit radius tends to infinity ($a\rightarrow\infty$) the image distance becomes $|v|=|-\ u|=d$(say) and from (2.5) the value of the image charge becomes $q'=-q$ (as $a\rightarrow y$ in this limit). This analogy with optics justifies the observation that the grounded infinite conducting plane problem in electrostatics can be deduced from grounded conducting sphere problem in the limit $a\rightarrow\infty$.
Conjugate foci relationship
---------------------------
From the form of (2.4), it is apparent that the conjugate foci relationship also holds here. How to see it is indeed the case? One can show that the field inside a hollow conducting sphere of radius $a$ (containing a point charge $Q$ at a distance $b$ from the centre) is the same as if there is no sphere and a charge $Q'=-\frac{aQ} {b}$ is at distance $\frac{a^2}{b}$ on the same axis outside the sphere. If in this inverse problem, we insist $Q\rightarrow q'=-\frac{aq}{y}$ and $b\rightarrow y'=\frac{a^2}{y}$, then value of the image charge becomes $Q'=-\frac{aQ}{b}=
+\frac{a\frac{aq}{y}}{\frac{a^2}{y}}=q$ -which is the value of the real charge in the original problem. Similarly, the distance where the image charge $Q'$ forms is $\frac{a^2}{b}=\frac{a^2
}{\frac{a^2}{y}}=y$ -which is the distance from the centre where the real charge is placed in the original problem. The corresponding case in optics is that a real object placed in front of a concave mirror (within the focal length) forms a virtual image behind the mirror.
Application: Image problem for extended charge distribution
===========================================================
The similarity with optics can be exploited to calculate the potential function due to an extended real charge distribution placed outside a grounded conducting sphere (see Figure 4). Now, invoking the differential form of (2.5), we have (symbols carrying the usual meaning): $$\frac{dq}{u}=-\frac{dq'}{v}$$
In Figure 4, we denote source and image charge distributions with double primes and single primes respectively. If the real charge distribution is specified with respect to the origin $O$, (5.1) becomes: $$\frac{\rho(r'',\theta'',\phi'')\ d\tau''}{r''-a}=-\frac{\rho'(r',\theta',\phi')\ d\tau'}{(a-\frac{a^2}{r''})}$$ Writing out the volume elements explicitly and noticing that the solid angle elements are equal, $$\frac{\rho(r'',\theta'',\phi'')\ r''^2 dr''}{r''-a}=-\frac{\rho'(r',\theta',\phi')\ r'^2 dr'}{(a-\frac{a^2}{r''})}$$ Notice that $r'=\frac{a^2}{r''}$ and from (2.4), the ‘longitudinal magnification’ is $\frac{dv}{du}=-\frac{v^2}{u^2}$ $$|\frac{dr''}{dr'}|=-\frac{du}{dv}=+\frac{u^2}{v^2}=\frac{(r''-a)^2}{(a-\frac{a^2}{r''})^2}$$ Hence, we can express the charge density of the image distribution in terms of the charge density of the real charge distribution as follows: $$\rho'(r',\theta',\phi')=-\rho(r'',\theta'',\phi'')\frac{r''^2}{(r''-a)}(a-\frac{a^2}{r''})\frac{(r''-a)^2}{(a-\frac{a^2}{r''})^2}\frac{1}{(\frac{a^2}{r''})^2}$$ After simplification, this becomes $$\rho'(r',\theta',\phi')=-\rho(r'',\theta'',\phi'')\frac{r''^5}{a^5}$$ This derivation is alternative to the one given in reference \[3\]. However, our approach is more intuitive and helpful to undergraduate students. The potential at some field point $\bf{r}$ then becomes: $$\Phi({\bf{r}})=\int_{real}\frac{\rho({\bf{r''}})}{|{\bf{r}}-{\bf{r''}|}}\ d\tau''+\int_{image}\frac{\rho'({\bf{r'}})}{|{\bf{r}}-{\bf{r'}}|}\ d\tau'$$ If the boundary of the real charge distribution is known: $r''=r''(\theta,\phi)$ is known (it should be among the known quantities of the problem), then the first integral can be evaluated. Again, given $r''=r''(\theta,\phi)$, we can also evaluate the boundary of the image distribution as we know $r'=\frac{a^2}{r''}$ and $\theta''=\theta'$ and $\phi''=\phi'$. Then, (5.6) reduces to: $$\Phi({\bf{r}})=\int_{real}\frac{\rho({\bf{r''}})}{|{\bf{r}}-{\bf{r''}|}}\ d\tau''-\int_{image}\frac{r''^5}{a^5}\frac{\rho({\bf{r''}})}{|{\bf{r}}-\frac{a^2}{r''}{\hat{\bf{r''}}}|}\ d\tau'$$ Expressing $d\tau'$ in terms of $d\tau''$, we get $$\Phi({\bf{r}})=\int_{real}\frac{\rho({\bf{r''}})}{|{\bf{r}}-{\bf{r''}|}}\ d\tau''-\int_{real}\frac{r''^5}{a^5}\frac{\rho({\bf{r''}})}{|{\bf{r}}-\frac{a^2}{r''}{\hat{\bf{r''}}}|}\frac{a^6}{r''^6}\ d\tau''$$ In the last step, the limits of the image integral has been transformed as following: $$\int_{r'_{1}}^{r'_{2}}\rightarrow\int_{\frac{a^2}{r'_{1}}}^{\frac{a^2}{r'_{2}}}\equiv\int_{r''_{1}}^{r''_{2}}$$ So that the expression for potential at a field point becomes: $$\Phi({\bf{r}})=\int_{real}\frac{\rho({\bf{r''}})}{|{\bf{r}}-{\bf{r''}|}}\ d\tau''-\int_{real}\frac{a}{r''}\frac{\rho({\bf{r''}})}{|{\bf{r}}-\frac{a^2}{r''}{\hat{\bf{r''}}}|}\ d\tau''$$ Is this result consistent with the point charge case? Let us take a point charge at a distance of $y$ from the centre of the conducting sphere, so that $\rho({\bf{r''}})=q\delta(\bf{r''}-\bf{y})$. Hence, (5.9) shows that the potential at any field point $\bf{r}$ will be $$\Phi({\bf{r}})=\int_{real}\frac{q\delta(\bf{r''}-\bf{y})}{|{\bf{r}}-{\bf{r''}|}}\ d\tau''-\int_{real}\frac{a}{r''}\frac{q\delta(\bf{r''}-\bf{y})}{|{\bf{r}}-\frac{a^2}{r''}{\hat{\bf{r''}}}|}\ d\tau''$$ This simplifies to $$\Phi({\bf{r}})=\frac{q}{|{\bf{r}}-{\bf{y}|}}-\frac{a}{y}\frac{q}{|{\bf{r}}-\frac{a^2}{y}{\hat{\bf{y}}}|}$$ -which is the familiar result. Diving by $q$, we obtain the Green’s function of the problem.
Working Principle
-----------------
In general, we have to deal with an extended continuous charge distribution. Let us say, the real charge density $\rho(r'',\theta'',\phi'')$ is distributed in a sphere at some fixed distance $r''
_0$ from the centre of the grounded sphere. It subtends an angle of $2cos^{-1}\frac{a}{r''_0}$ at $O$. Regarding the principal axis as the reference axis in the polar coordinates, the polar equation of the sphere is $r''^2+r''{_0}^2-2r''r''_{0}cos\theta=a^2$. For $\theta\leq cos^{-1}\frac{a}{r''_0}$, the two points where the real-source coordinates cut the sphere are given by the following $r''=r''(\theta'',
\phi'')$ form: $r''=r''_{0}cos\theta\pm\sqrt{a^2-{r''_{0}}^2 sin^{2}\theta}$. With this, it is possible to solve the two integrals in (5.9) and thereby, solve the image problem for an extended, continuous charge distribution. Needless to say, this form is consistent with the usual form derived in standard textbooks (reference \[2\]) for a sphere the potential on which is zero.
Comments
--------
We have made a nice guess about how to extract all information about image charge in grounded conducting sphere image problem in electrostatics. In return, it shed considerable light on the analogy between the electrostatic image and image in mirror-optics. The corollary that standard results apply equally if the real charge is placed inside the conducting sphere (and the image charge is produced outside the sphere) is just the mere reflection of the ‘conjugate foci’ relationship in electrostatics.
The new formulation allowed us to devise the formula needed to solve the image problem for extended real charge near a conducting sphere. We offer a picture more vivid as well as more informative. The standard approach does not possibly let one know much about the distorted image charge distribution: how does its charge density vary or how does its boundary look like (correlation with the boundary of the real charge). In comparison, our treatment directly finds these details and eventually, just add the potentials due to real charge and image charge, as is done for the point charge case.
By the way, if the potential on the conducting sphere is non-zero, Dirichlet boundary condition is to be used. This results in the following additional term in our formula: $$-\frac{1}{4\pi}\oint\Phi(a,\theta'',\phi'')\frac{(r^2-a^2)}{a(r^2+a^2-2ar cos\gamma)^{3/2}}a^2 d\Omega''$$ where $cos\gamma=\hat{\bf{r}}\cdot\hat{\bf{r''}}$. In the standard approach also, one needs to add this boundary term to the generic Green’s function for the ‘grounded’ conducting sphere.
We wish to remind the reader that the analogy we have seen in this article is not complete. In optics, a spherical mirror can be a portion of a sphere and still can form an image. Because only those light rays that are close to the axis are needed to form it. However, in electrostatics, one needs a full spherical conducting surface to form the image. This also explains why do we need infinite plane conductor to form an electrostatic image but a finite plane mirror suffices to form optical image. We chose the term mirror (and not the term lens) as the electric field $\bf{E}$ of the real charge does not penetrate the conductor like light ray actually does not penetrate a mirror.
Pedagogic Interest of the article
=================================
Image problems are part of the physics curriculum in undergraduate and graduate level courses in universities. To the undergraduate students in introductory electrodynamics course, the analogy given in section $2$ (mirror equation, magnification formula and conjugate foci relation) will be a pleasant surprise and a more familiar way to calculate image charges (as they are expected to have covered lens/mirror optics in high school level). On the other hand, the graduate students will find the alternative treatment of image problem for extended charge distribution interesting. The article deals with an interdisciplinary topic; so, it might attract the general physicists as well while they see that the same basic principle connects apparently different areas.
I am very much grateful to sincere supports and encouragements from Dr. Debapriyo Syam, Sayan, Tanmay, Manoneeta and Tamali. The anonymous reviewer of the paper also helped me in improving the article.
References
==========
[5]{}
J.D. Jackson 1999 [*Classical Electrodynamics*]{} (Springer),p 59-60.
Greiner 1998 [*Classical Electrodynamics*]{} [Springer]{} p 50-52, 59-60.
Static Image Principle for the Sphere in Bi-Isotropic Space (H$\ddot{a}$nninen and Lindell) RADIO SCIENCE, VOL. 35, NO. 3, PP. 653-660, 2000
Patrick Tam 2008 [*A Physicist’s Guide to MATHEMATICA*]{} [Second Edition, Elsevier]{} p 590
Wolfram Research, Inc., Mathematica, Version 6.0, Champaign, IL (2007).
| |
Lab: Authentication bypass via encryption oracle
This lab contains a logic flaw that exposes an encryption oracle to users. To solve the lab, exploit this flaw to gain access to the admin panel and delete Carlos.
You can log in to your own account using the following credentials:
wiener:peter
Solution
-
Log in with the "Stay logged in" option enabled and post a comment. Study the corresponding requests and responses using Burp's manual testing tools. Observe that the
stay-logged-incookie is encrypted.
-
Notice that when you try and submit a comment using an invalid email address, the response sets an encrypted
notificationcookie before redirecting you to the blog post.
-
Notice that the error message reflects your input from the
Invalid email address: your-invalid-email
Deduce that this must be decrypted from the
notificationcookie. Send the
POST /post/commentand the subsequent
GET /post?postId=xrequest (containing the notification cookie) to Burp Repeater.
-
In Repeater, observe that you can use the
POSTrequest to encrypt arbitrary data and reflect the corresponding ciphertext in the
Set-Cookieheader. Likewise, you can use the
notificationcookie in the
GETrequest to decrypt arbitrary ciphertext and reflect the output in the error message. For simplicity, double-click the tab for each request and rename the tabs
encryptand
decryptrespectively.
-
In the decrypt request, copy your
stay-logged-incookie and paste it into the
notificationcookie. Send the request. Instead of the error message, the response now contains the decrypted
stay-logged-incookie, for example:
wiener:1598530205184
This reveals that the cookie should be in the format
username:timestamp. Copy the timestamp to your clipboard.
-
Go to the encrypt request and change the email parameter to
administrator:your-timestamp. Send the request and then copy the new
notificationcookie from the response.
-
Decrypt this new cookie and observe that the 23-character "
Invalid email address:" prefix is automatically added to any value you pass in using the
notificationcookie to Burp Decoder.
- In Decoder, URL-decode and Base64-decode the cookie.
- In Burp Repeater, switch to the message editor's "Hex" tab. Select the first 23 bytes, then right-click and select "Delete selected bytes".
-
Re-encode the data and copy the result into the
notificationcookie of the decrypt request. When you send the request, observe that an error message indicates that a block-based encryption algorithm is used and that the input length must be a multiple of 16. You need to pad the "
Invalid email address:" prefix with enough bytes so that the number of bytes you will remove is a multiple of 16.
-
In Burp Repeater, go back to the encrypt request and add 9 characters to the start of the intended cookie value, for example:
xxxxxxxxxadministrator:your-timestamp
Encrypt this input and use the decrypt request to test that it can be successfully decrypted.
-
Send the new ciphertext to Decoder, then URL and Base64-decode it. This time, delete 32 bytes from the start of the data. Re-encode the data and paste it into the
notificationparameter in the decrypt request. Check the response to confirm that your input was successfully decrypted and, crucially, no longer contains the "
Invalid email address:" prefix. You should only see
administrator:your-timestamp.
-
From the proxy history, send the
GET /request to Burp Repeater. Delete the
sessioncookie entirely, and replace the
stay-logged-incookie with the ciphertext of your self-made cookie. Send the request. Observe that you are now logged in as the administrator and have access to the admin panel.
-
Using Burp Repeater, browse to
/adminand notice the option for deleting users. Browse to
/admin/delete?username=carlosto solve the lab. | https://portswigger.net/web-security/logic-flaws/examples/lab-logic-flaws-authentication-bypass-via-encryption-oracle |
Levi bakes a brownie cake for Mummy's birthday today!
What a day full of fun and joy. We baked a cake, received a lot of cake slices from friends, and we manage to make a nice video out of it.
We make a simple brownie cake that has only 6 ingredients:
- Brownie Mix
- Butter
- Water
- Eggs
- Walnut
- Chocolate chips
It's super easy to make and makes it a fun activity that can be done with kids.
YouTube Journey DAY 16
Half of the month has passed and we're into our next half making videos on YouTube.
I've been checking out some mobile Gimbal stabilizers so that we can do some filming outdoors. With all that shaking when holding a mobile, the only way is to upgrade our gear so that we can do this.
I'm waiting on more crypto earnings to go through before cashing out a little to get one of those Gimbals.
Let's hope more positive move upwards happen in crypto and I'll definitely be coming out with better and better quality content.
Appreciate all the support and don't forget to subscribe to our channel to get our video notification daily.
Love, | https://ecency.com/hive-174578/@danielwong/youtube-journey-day-16-brownie-cake-baking-with-levi-for-mummy-s-birthday |
According to the Japanese State Broadcaster NHK, experts have made an astonishing discovery in a Buddhist statuette in Japan. Investigators, from the Nara National University examined the statuette and they were amazed to discover some 180 artifacts inside the object, that is usually kept at the Hokkeji Temple in the ancient Japanese capital of Nara. Some 150 artifacts – mainly scrolls – were discovered in the body of the statuette and another thirty in its head. This raises the question as to why the items were apparently hidden in a statuette and forgotten. Not even the head priest had any inkling that the figure contained such a treasure trove.
The Statuette of the BodhisattvaThe Hokkeji Temple was built in the 8 th century AD when Buddhism was becoming very popular. At the time Nara was one of the centers of Buddhist activity in Japan. The temple is home to many treasures and the statue with the hoard of artifacts is just one of the many rare and precious objects housed at the site.
The statuette portrays Monju Bosatsu, a Bodhisattva, that is a person who has elected not to enter Nirvana or to become a Buddha, in order to help humanity to escape suffering. The statue is believed to be approximately seven centuries old and has been in the possession of the temple for many years. The statuette of Monju Bosatsu only stands at 73 cm or 30 inches high.
- The Seven-Branched Sword: The Mystical Ceremonial Sword of Japan
- Two Rare Swords found in 6th-century Underground Tunnel Tomb in Japan
- The Amazing Story of Yasuke: The Forgotten African Samurai
Discovery of the ArtifactsThe team from the Nara National University used a CT scanner to examine what was in the statuette and this allowed them to see inside the figure of the Bodhisattva. The investigators discovered that there was a hollow space in the statute from its bottom to its top. The scan revealed the hoard that was contained in the figure and which they believe had not seen the light in many centuries. Officials believe that the artifacts and scrolls have never been removed from the statuette, they have yet to determine how they were placed in the interior of the figure of the Bodhisattva.
- Shipwreck found in Japan believed to be from 13th century Mongol invasion
- The engraved tablet found inside hidden compartment of thousand-hand Bodhisattva statue
- The mummified monk inside a Buddha statue
The find of the artifacts has raised an important issue for the investigating team and for the temple. The items are undoubtedly of great historic and archaeological interest, but they cannot be examined at present as they are sealed inside the statuette of Monju Bosatsu. There is a dilemma for the team. Do they damage a rare statuette to reveal the hoard to the world, or do they simply leave the scrolls and objects where they are? According to Newsweek ‘whether scientists will crack into the figurine to reveal the artifacts inside remains to be seen’.
It seems unlikely that anyone will establish why the artifacts were placed in the statuette and their exact nature for some time to come. | http://www.oom2.com/t55095-hoard-of-scrolls-and-artifacts-discovered-in-antique-japanese-statuette |
There are more than 17 Sydney Metropolitan Associations which compete annually for the Interdistrict tennis competition. This event is hosted by the NSW Hardcourt Tennis Association, who formed in 1924. The original and premier event in this series is the Blackwell Cup for Open Men, and this event was originally contested in 1921.
ISLTA has a proud tradition in representative tennis; and has won more Interdistrict titles than any other association. Our association (ISLTA) co-ordinates an Interdistrict team comprised of veteran, senior and junior tennis players. The name “Illawarra Tennis” is engraved on the George McKerihan Shield (as the champion association) 33 times since 1947.
The current format for the Interdistrict series is that most categories play a 6 week home and away series followed by a two week finals series, and this has generally been played in the period July to September. There are a large number of events available for competition, and each event often has a number of divisions/levels to cater for players of varying standard from good to elite standard competing by age. A summary of the events are;
(1) Junior Tennis. Boys and girls team in ages 16U, 14U, and 12U.
(2) Senior Tennis. Mens and womens open teams.
(3) Veteran Tennis. Many categories of veterans teams for men and women over the age 35 and 50.
There is often a player rotation so your kids don’t have to play every week; if you prefer not to play all weeks, please let your team manager know this so he can arrange the roster of players. While we will invite some players to trial, it's important for you to nominate to play so that we can add you to our contact list for updates. Nominations are generally needed quite early each year (late February/March) leading to selection trials and later a teams day (for shirt presentation, photos and a BBQ) , so please check website, Facebook, or ask your coach for details. | http://stgeorgesutherlandtennis.com.au/content/interdistrict |
If I were a superhero, I will be a time stop person. I need this skill because I have to do everyday tasks, complete my assignment and homework, play, and spend time with my friends, so I do not get enough time, and I need that skill. My greatest motivation is to the Lord. I want my roots to come from the heavens. I like the power to heal men. I just do not want to be invisible or flyable. Instead, I would like the powers to physically and psychologically cure others. This is a mindset which I believe to be useful to the world and which will lead to beneficial changes.
The goal of a superhero generally is to do good works and help others. There are various ways a person with special powers could achieve this feat. Though I believe it would suit me better to have the ability to heal people. Having power does not allow me to wear any extravagant outfits or costumes. Rather, I guess I had to dress like anyone else so as not to differentiate myself from others. It can be harmful to show our abilities off to the world because it will give you a big ego. If I have ever acquired this talent, I hope I can use it to the best of my ability.
I recognize why we all want to get greedy for more because people have tremendous forces and can exploit it. This straightforward and minimal skill would be easy to carry out. It could be done easily and would remain who I was but would most likely protect my gift cautiously from others’ prying curiosities.
My Dad- my superhero
My father is a lifelong friend of mine. I love my Dad a lot. There was not even a single day on which he did not care about me. My father takes special care to make sure I am healthy and helpful. If I am ill, he stumbles and continues to worry until I become all right again. Only in those moments did I know the deep love that he has for me. Just a handful of people in our lives help us to lead a happier life. But one father is the only one working hard for the family’s goodness. If in this universe there can be a SuperHero, it is my Dad, and there is no one who can replace him.
My father is a special personality who can inspire others with ease. I love the attitude of my father. From my Dad, I learned a positive attitude. He’s concerned about our learning about our wellbeing and happiness. He continues to work without breaks every day; all I know is that he continues to do so is that he can earn more so that we will all be satisfied.
My father taught me to see flaws as the road to success. I haven’t even seen him depressed in a single day. He’s my role model, and I enjoy living by his values.
Spiderman My Superhero
We all hear about Spiderman, the great Hero. So many fans are there for the Superhero Spiderman. My friends and I am the huge fan and admirer of Spiderman. We love Spiderman because he is a Super Hero with original powers and saves lives. Spiderman still protects the city and people in it, with all his abilities. Spiderman defeats all evildoers and wicked people, and they very much fear Spiderman. Spiderman ‘s strength is remarkable and inspiring. While Spiderman is, in fact, a nerdy young man, he has gained fame for his Super Power and the good deeds he has done to the people with his great strength. I adore Spiderman a lot. He is a Superhero of mine.
Spiderman is a fast-paced superhero. He can travel from one spot to another so rapidly using his Web-slinging ability, which no other normal human can do. When wicked people are threatening people at the right moment, Spiderman rescues them. While the villains may be powerful, Spiderman has never stopped doing the right thing. Spiderman risked all his might and strength to stand alongside good people.
That’s enough to let us impress. His powers and actions are so interesting that he still encourages me to support others, to do good to others, and to stand up to evildoers.
What will I do if I will be a superhero?
Superman, Batman, Spider-Man, Thor, Hal Jordan, Wonder Woman, Captain America, Wally West, Mr. Fantastic, Invisible Woman, Wolverine, Iron Man, Super Lady, Hercules and several more prevail in the universe. The infant, teenager or adult will still think of the powers they see in the films and have these perceptions like-
If I were a Superhero, I would hire the spider man’s powers and own the spot. I would be busy taking photos of the city from distinct viewpoints to get an amazing experience with no restraints.
If I were a Super Hero, I would have recruited a clown of me, who would play with me, go to school on my side, do my homework, and blame himself for my mistakes.
If I were a Super Hero, I would be a wizard, turn the entire universe into a Harry Potter show, and celebrate every magic universe movement.
Conclusion
The lessons that superheroes can teach us are not limited to telling stories and drawings but are limited to moral decisions and right and wrong, good vs. evil. I want them to know that an evil deed never goes unpunished, and one person can make a difference. I want them to know that superheroes are just as strong as the people who make them, and maybe there is a superhero in us all. To let us all find the real hidden power within ourselves and generate a superhero within us. Superheroes are not born by birth; they are made by immense labor and hard work. So focus on hard work one day you will become the superhero of others. Are you looking for original essays on similar topics? You are not alone, SmartWritingService and its essay writers for hire will help with your papers on different superhero topics.
There are many super heroes prevailing in the world like Superman, Batman, Spider Man, Thor, Hal Jorden, Wonder Woman, Captain America, Wally West, Mr. Fantastic, Invisible Woman, Wolverine, Iron Man, Super Girl, Hercules and many more. The child, teenager or adult would always think of powers like they see in the movies and have perceptions like:
- If I was a SuperHero, I would hire the powers of spider man and would own that place. I would be busy in taking photographs of the city from different angles to get incredible experience without any restrictions.
- If I was a Super Hero, I would hire the powers of Goku from dragon Ball Z, keeping two fingers on the forehead, thinking about the place I want to explore and would have been there in few seconds.
- If I was a Super Hero, I would hire have made a clown of me, who would play with me, go to school on behalf of me, do my homework, take my mistakes blame on himself.
- If I was a Super Hero, I would regenerate the planet earth and eliminate the earth from global warming and convert the saline water into fresh water so that we can use as much as we can.
- If I was a Super Hero, I would be a magician and change the whole world into a Harry Potter series and enjoyed every movement of magic world.
- If I was a Super Hero, I would be having the power to change the season and have fun to enjoy every weather in any season.
If I was a Super Hero, I would have powers of flying and be around people to help them and be saving to everyone and look alike. I would be having no specific uniform or if there is than it would be as simple as school uniform. I would have gone to the Island to spend time alone-away from everyone in peace.
Some people only focus to help others and if they were superhero, they would have the ability to heal the illness of the world with the help of music and rescue people from death.
They would also cure the diseases like Aids, cancer, tumor and many other harmful diseases and not to pay the millions of rupees to the hospitals, especially for the poor families.
If I were having super powers I would turn myself into a super hero. I would not be a super villain whose only purpose is to hurt people and take over the world. I do not want the responsibility to rule people like a King but want to prevail democracy in the world because it’s not my cup of tea. If I were a Super Hero, I would have eliminated the Dharma and the varieties of castes prevailing in the world.
If I was a Super Hero, I would have changed the constitution of India to a better one and the major focus will be on the rapist. He would be given direct death and no imprisonment for life. The super hero will be having ability to fight crime and rescue all the criminals around the world to bring peace and harmony in the whole world.
I would also choose super speed faster than the bullet so that no one can shoot me and I would reach the places not in minutes but in seconds. These powers would help me to fight many people at a time and to fight in various angles to gain victory.
Last but not the least, I would purely want to be a child again who would never grow up and enjoy the childhood till end of the life…
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FAQs
What would I do if I were a superhero? ›
If I were a superhero, I would save everyone from attacks, bullying and many other things. I would also sacrifice my life to save somebody who is in danger. I would also stop criminals and villains from entering the city or country or from doing any harm or damage to the city.
How do you start a superhero essay? ›
- Introduction. ...
- First, create a name for your hero. ...
- Leave notes with interesting ideas. ...
- Regarding how to start a superhero story, you should understand that each superhero requires a villain in order to make the story more interesting. ...
- Create a backstory for all the characters.
What is your idea of a superhero? ›
A superhero is a person who does heroic deeds and has the ability to do them in a way that a normal person couldn't. So in order to be a superhero, you need a power that is more exceptional than any power a normal human being could possess, and you need to use that power to accomplish good deeds.
What is a superhero summary? ›
A superhero is a character with extraordinary powers that performs heroic actions. Unlike police, firefighters or doctors, all of whom are heroes in their own right, superheroes are defined by their unique capabilities, such flight, strength, speed or invincibility (to name a few).
What is an example of a superhero? ›
Long-running superheroes and superheroines such as Batman, Superman, Wonder Woman, Spider-Man, Captain America, and Iron Man have a rogues gallery of many such villains.
What if I were a Superman? ›
If I were a superman I would make the world a better place. The first thing I would with the superpower would be plant plenty of trees, first in Indian cities and then all across the world where the forest cover has reduced. It would reduce the problem of pollution and global warming.
How do you introduce a superhero? ›
Introduce a character by showing him saying something — or even better, doing something — that shows how he usually feels and behaves, and you'll help the reader understand the most important things about him. And you'll help yourself tell the character's story. David Seidman has written, edited, and marketed comics.
Who are your favorite superheroes? ›
- Superman.
- Spider-Man.
- Batman.
- Captain America.
- Iron Man.
- Wonder Woman.
- Aquaman.
- Captain Marvel.
Who is the superhero in the world? ›
|Rank||Superhero||% Share in Study|
|1||Spider-Man||48.7%|
|2||Wonder Woman||12.8%|
|3||Batman||9.2%|
|4||Iron Man||8.5%|
Who is the best superhero? ›
- #8: Green Lantern. ...
- #7: Captain America. ...
- #6: Wonder Woman. ...
- #5: Iron Man. ...
- #4: Wolverine. ...
- #3: Superman. ...
- #2: Spider-Man. ...
- #1: Batman. It was a tough decision, but taking the top spot is the Dark Knight.
What are the qualities of super hero? ›
- Extraordinary ability.
- Moral conviction.
- Great courage.
- A mission to serve.
Why do we love superheroes? ›
Robin Rosenberg, a clinical psychologist, suggested that superheroes allow us to find “meaning in loss and trauma, discovering our strengths and using them for a good purpose.” Many heroes have their own personal problems they deal with, along with the responsibility of protecting/saving the world.
Who was the first super hero? ›
DC Comics introduced the first costumed superhero, Superman, in Action Comics #1 (June 1938).
What is a good name for a superhero? ›
|Vindicate||Ironside||Torpedo|
|Turbine||Kraken||Granite|
|Glazier||MechaMan||Fortitude|
|Cast Iron||Fireball||Polar Bear|
|Turbulence||Mako||Captain Victory|
What are the 5 main superpowers? ›
China, France, Russia, the United Kingdom, and the United States are often referred to as great powers by academics due to "their political and economic dominance of the global arena". These five nations are the only states to have permanent seats with veto power on the UN Security Council.
Is Super hero one word? ›
4) SUPER HERO IS TWO WORDS; SUPER-VILLAIN IS TWO WORDS WITH A DASH. This all goes back to the joint trademark that Marvel and DC have on the terms super hero and super-villain—in their case, it's super-hero and super villain.
Why is Superman a hero? ›
Superman is a real hero because he saves a lot of people with his special powers. He is the strongest man in the world. He also has to fight with criminals who are after his powers. That's why he is a big hero for a lot of people.
Why I would like to be a Superman? ›
While they are nice, the real reason I want to become Superman is because of the impact he can make on the world. As a boy I was always drawn to Superman because he was the ideal superhero, strong, saving lives, and down to earth, but as I grew older I understood more and more about Superman as a character.
Why did you choose Superman? ›
Superman is my favorite superhero because he is a man of good morals, a humanitarian, and he is privileged with good looks and special powers. Superman is my favorite superhero because he possessed great superpowers such…show more content… He rescues civilian and saves the world from crisis and from villains.
How do you start a hero story? ›
- Know what is heroic. ...
- Begin humbly. ...
- Create great obstacles. ...
- Create a compelling villain. ...
- Create worthy goals. ...
- Populate your story with friends and guides. ...
- Give your hero a flaw. ...
- Create an "all is lost" moment.
How can I make my own superhero? ›
How to Design Your Own Superhero - YouTube
How do you start a superhero origin? ›
The 3 Kinds of Superhero ORIGIN STORIES! || Comic Misconceptions
What is the best superhero and why? ›
Thor. The God of Thunder is one of the greatest superheroes of all time and here's why. The man is a God who does everything in his power to keep peace across the Nine Realms. He is the son to arguably the most powerful character in Marvel comics, Odin and wields one of the Universe's greatest weapons in Mjolnir.
Who is the most liked superhero? ›
If you go by at least one analysis of the past year's Google search data, that hero is Spider-Man. According to online entertainment retailer Zavvi, the web slinger is the world's most popular superhero with more than 5 million average searches per month.
Who is India's super hero? ›
Among some of the popular superheroes are: Nagraj, Dhruv, Doga, Parmanu, Shakti, Bhokal, Bheriya, Tiranga, Inspector Steel, Anthony, Super Indian and Shaktimaan.
Who is India first superhero? ›
Hrithik was born to yesteryear Bollywood actors Rakesh and Pinky Roshan on January 10, 1974. As a child, Hrithik worked in many films as a child artist. His first film as a child was Aap Ke Deewane (1980), directed by his father. Then he essayed the role of a young dancer in Aasha (1980).
Who is the most human superhero? ›
The Punisher (Frank Castle)
Punisher is arguably one of Marvel's most impressive humans. He's taken (and dished out) more pain than almost anyone, and his ability to survive and to overcome obstacles that would make most men shake in their boots place him squarely in the ranks of the greatest human heroes of all time.
Who is the biggest superhero? ›
- Spider-Man (5,100,000 average monthly Google searches)
- Batman (3,400,000 average monthly Google searches)
- Superman (2,000,000 average monthly Google searches)
- Captain America (1,900,000 average monthly Google searches)
- Hulk (1,800,000 average monthly Google searches)
Who is the fastest superhero? ›
Quicksilver
Quicksilver…the man many believe to be Marvel's answer to DC's The Flash. Quicksilver, as his name implies, is really fast. His speed has been estimated well over 8500 miles per hours. To put that into perspective, even the fastest car in the world is only capable of achieving speeds of 301 miles per hour.
How do you write a superhero? ›
Decide what type of superhero to create, such as whether the hero will be human or some type of creature. Give the human character a backstory, a day job and other humans to interact with. Include the backstory in the first chapter of your novel or in flashbacks throughout the novel to develop your character.
What is a superpower hero? ›
A superpower is a currently fictional superhuman ability. Superpowers are typically displayed in science fiction comic books, television programs, video games, and films as the key attribute of a superhero.
Why are superheroes so cool? ›
Superheroes are meant to inspire. They represent someone we are not, or someone that can do things that we can't. They can provide an escape into a world where someone is there for us even when our protectors or our medical and social institutions have let us down.
Why do I like superhero movies? ›
While part of the appeal of superhero films is their fantastical aspect, which we can use as a form of escapism from the troubles we face in reality, superhero films are also popular because of the opposite: they mirror the human experience and that makes them more relatable and closer to home.
Why are heroes so popular? ›
They tell stories in which powerless, average people somehow acquire a special capacity that makes them undeniably significant, individual and impervious to assault. Thus empowered, they can fight the world and win, sometimes with the help of others who are similarly gifted.
Who made superheroes? ›
Created by Lee Falk (USA), the first superhero was The Phantom, who debuted in his own newspaper comic strip on 17 Feb 1936.
Who was the first girl superhero? ›
No, the FIRST female superhero was Miss Fury, created, written, and drawn by Tarpé Mills, who also happened to be a woman. June Tarpé Mills was born in Brooklyn in 1912 or 1918, depending on the source.
Are superheroes real? ›
Real-life superheroes are notably prevalent in the USA compared to other countries, which may be attributed to the greater popularity of superhero comic books. One of the earliest examples of a RLSH was California's Richard Allen Pesta, alias Captain Sticky.
Who is the strongest superhero in India? ›
1. Shaktimaan. Shaktimaan attained his heroic powers through deep meditation and was capable of activating certain chakras which gave him powers.
What are my superhero colors? ›
- RED – bold, energetic, passionate, determined.
- ORANGE – enthusiastic, potent, heat, humor.
- YELLOW – attentive, safe, energetic, ostentatious.
- GREEN – nature, growth, safe, harmonious, mystic.
- BLUE – deep, stable, knowing, trust-worthy, confident.
- PURPLE – royal, knowledgeable, untouchable, creative.
What superpower would you most like to have and why? ›
- Flight.
- Telepathy.
- Super Speed.
- Invisibility.
- Talking to Animals.
- Intangibility.
- Force Field.
- Super Smart.
Could have any superpower which one would you want and why? ›
“The superpower that I want is the ability to fly. I'd save those in danger when travelling by air. I would use this power to immediately respond to any emergency situation, without being bothered by any traffic in the streets. I also want to see the beauty of the world.”
What is your super power? ›
A person's super power is their particular genius: the specific, unique and specialized skill that they bring to the workplace.
How do u become a superhero? ›
- Superheroes want to do good for others. They want to be of service.
- Superheroes take initiative. ...
- Superheroes have confidence in their abilities and their own competence.
- Superheroes believe that they can accomplish anything that they set out to do.
What is a cool superpower? ›
The Coolest Superpowers
If your character has permanent invisibility, then they really don't need clothes at all (unless they want to be seen). Phasing: The ability to pass through solid objects can be one of the most useful superpowers a person can have.
Why flying is the best superpower? ›
Flight, Flight is better than any other superpower because, it can transport you faster than any other superpower. There are two different types of flight, the most common one is buoyant flight. Buoyant flight is a human constructed creation which is lighter than air like a blimp.
What's your superpower again I'm rich? ›
What are your superpowers again? Bruce Wayne : I'm rich.
Is it possible to get super powers? ›
No such gene exists in humans, and we simply don't know enough about the genetic potential of our genes to produce superhuman abilities. We do know that some humans already possess abilities that appear like superhuman powers.
What are my superpowers at work? ›
Superpowers At Work
They range from empathy—a strong ability to understand client/user/team needs—to systems thinking—understanding all of the pieces of a process—to creative thinking, grit, and decisiveness, among others.
What are the 5 great powers? ›
China, France, Russia, the United Kingdom, and the United States are often referred to as great powers by academics due to "their political and economic dominance of the global arena". These five nations are the only states to have permanent seats with veto power on the UN Security Council.
How do you answer the question about superpower? ›
Select a superpower that is simple but effective and aligns with your biggest strength. This helps ensure your answer focuses on your strengths rather than the superpower itself. Choose a strong superpower that requires no extra context as to how it works. For example, choose something like flying or X-ray vision.
Is leadership a superpower? ›
A leader's “superpower” is their most positive and impactful personality asset. It is the part of them that influences, persuades and inspires others to follow.
How do you become a superhero for kids? ›
Ten Rules of Being a Superhero - Kids Books Read Aloud - YouTube
Is super hero real? ›
Real-life superheroes are notably prevalent in the USA compared to other countries, which may be attributed to the greater popularity of superhero comic books. One of the earliest examples of a RLSH was California's Richard Allen Pesta, alias Captain Sticky.
How do I give my character superpowers? ›
- Make them wander into a lab and spill some chemicals on themselves.
- Subject them to otherwise deadly radiation.
- Have them struck by lightning.
- Have them bitten by a spider. ...
- Give them cybernetic augmentations.
- Test that new brand of Super Serum on them. ...
- Give them something to compensate for a disability. | https://yodack.com/article/if-i-were-a-superhero-essay-on-super-hero-for-class-students |
Q:
Get the distance from a root to a node with given value in a binary tree: Algorithm correctness
Here's my code
public int getDist(Node root, int value)
{
if (root == null && value !=0)
return -1;//
if(root.value == value)// we have a match
return 0;
if(root.getLeft()!=null)
int left =1+ getDist(root.getLeft(),value);
int right = 1+getDist(root.getRight(),value);
if(left ==-1 && right== -1)
return -1;//not found
return Math.max(left,right);
}
I would appreciate any feedback on the correctness of the above approach or any optimizations.
A:
As it stands your code won't work as intended. Consider this on the other hand:
public int getDist(Node root, int value) {
// value is never in an empty subtree
if (root == null)
return -1;
// found value, distance from root is 0
if(root.value == value)
return 0;
// find distance from root of left subtree
int left = getDist(root.getLeft(),value);
// find distance from root of right subtree
int right = getDist(root.getRight(),value);
// value not found in either subtree
if(left == -1 && right == -1)
return -1;
// if the value was found,
// return the distance from the root of the subtree + 1
return 1 + Math.max(left,right);
}
All I changed was remove some superfluous checks and move the +1 after the check for "value not in either subtree". The effect this has is the following: if the recursion finds that the value is not in a subtree, then the return statements will ripple up the value -1 all the way to the root of the subtree without changing it, keeping the information "value not here" intact. If the value was found in at least one subtree, then it can't be that both left and right are -1 so that check will fail and the return statement at the end will give back the intended value.
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Q:
Relations Definition and Example
I'm really struggling with grasping the concept of relations. Take this for example:
$\begin{array}{l}{\text { Let } A=\{a, b, c\} \text { and } B=\{1,2,3,4\} . \text { Then } \mathcal{R}_{1}=\{(a, 2),(a, 3),(b, 1),(b, 3),(c, 4)\}} \\ {\text { and } \mathcal{R}_{2}=\{(1, b),(1, c),(2, b),(3, c),(3, c),(4, a),(4, c)\} \text { are relations between } A \text { and } B . \text { Define } \mathcal{R}}\end{array}$
From lectures I have the following definition for a relation
A relation on a set $X$ is a statement about all ordered pairs of $X$. For a given pair $(x,y)$, the relation might be true or false
The example given was the operator $<$ , I can see how this fits the definition. But, the first example I have now idea how that can be seen as a relation. What do the indexes represent?
Another (simpler) example, which I decided to exhaustively list its ordered pairs, in order to fully understand the definition:
$S=\{1,2,3\} \text { and } a \sim b \iff a=1 \text { or } b=1 $
If we take all ordered pairs we have:
$S \times S = \{(1,1),(2,2),(3,3),(1,2),(1,3),(2,1),(2,3),(3,1),(3,2)\}$
I take that what $a \sim b$ represents would be a statement about whether two elements belong to a subset $S'$ of $S \times S$ , such that $$S' = \{(a,1),(b,1) \}, \text{ i.e } S' = \{(1,1),(1,2),(1,3),(2,1),(3,1)\}$$ If they do, then we can claim that $a \sim b$ or "a relates to b"
Is this correct? If so, then to prove that this is an equivalence relation would this mean the following:
Reflexive : $ \forall \ s \in S , (s,s) \in S' = \{(a,1) \}$
Symmetric : $ \forall \ s, r \in S (s,r) \in S'' = \{(b,1),(a,1)\}$
Transitive : no idea
A:
The connection between the definition of relation (a statement about all ordered pairs of $X$) and the list of ordered pairs is like naming a function by its values. So the relation can be characterized by the set of all pairs which are related. That's what $\mathcal{R}_1$ and $\mathcal{R}_2$ are. The indices are just there to differentiate the symbols for the two distinct relations. We're not really talking about a list of relations.
You did exactly the right thing with your relation $\sim$ and your list $S'$. Although following the text's notation it would be more conventional to call is $\mathcal{R}$:
$$
\mathcal{R} = \{(1,1),(1,2),(1,3),(1,3),(2,1),(3,1)\}
$$
When checking the properties, you don't reduce the original set of pairs. You need to check whether certain pairs are in $\mathcal{R}$, and if certain pairs are in $\mathcal{R}$ whenever certain other pairs are in it.
Is $\mathcal{R}$ reflexive? That's equivalent to checking if all three are satisfied: $(1,1) \in\mathcal{R}$, $(2,2) \in \mathcal{R}$, $(3,3) \in \mathcal{R}$.
Is $\mathcal{R}$ symmetric? That's equivalent to seeing if the reversal of every pair in $\mathcal{R}$ is also in $\mathcal{R}$.
Is $\mathcal{R}$ transitive? That's sort of equivalent to seeing if, whenever two elements are related to a third element, they are related to each other (at least, it's equivalent if the relation is also symmetric). I see that $(2,1) \in \mathcal{R}$ and $(1,3) \in \mathcal{R}$. Is $(2,3) \in \mathcal{R}$?
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Erasta Lyrics Follow
An eraser, (also called a rubber outside America, from the material first used) is an article of stationery that is used for removing writing from paper or skin. Erasers have a rubbery consistency and come in a variety of shapes, sizes and colours. Some pencils have an eraser on one end. Less expensive erasers are made from synthetic rubber and synthetic soy-based gum, but more expensive or specialized erasers are vinyl, plastic, or gum-like materials.
At first, erasers were made to erase mistakes made with a pencil; later, more abrasive ink erasers were introduced. The term is also used for things that remove writing from chalkboards and whiteboards. Ink erasers are denser, allowing them to erase pen marks. | http://www.lyricszoo.com/erasta/ |
Many computing applications require some amount of data entry. Some applications call for only a very limited number of characters, such as when a user enters a password or a PIN. Other applications, for example word processing or e-mail, require the user to enter extended amounts of data. For these latter applications, the keyboard reigns as the supreme data-entry device. Its design has been fashioned over more than a century to take advantage of people's nature manual dexterity. Today, typing on a keyboard is a common skill, and its supporting hardware and software are standardized and cheap.
Recently, small portable computing devices that support some form of data entry have become common. Such devices, typically smaller than a laptop computer, include, for example, cellular telephones, two-way pagers, and personal digital assistants. Often, these devices include a touch-sensitive display screen that serves both to display output from the computing device to its user and to receive input from the user. For some applications, the user “writes” with a stylus on the screen. The user's handwriting is decoded and becomes input to the computing device. In other applications, the user's input options are displayed as control icons on the screen. When the user selects an option by touching the icon associated with the option, the computing device detects the location of the touch and sends a message to the application or utility that presented the icon.
These devices often do not include a keyboard. To enter text, a “virtual keyboard,” typically a set of icons that look like the keycaps of a traditional keyboard, are painted on the screen. The user “types” by successively touching areas on the screen associated with specific keycap icons. This method works well for applications that require minimal data entry and where speed of entry is not a concern.
However, advancing data processing and communications technologies are enabling these small portable devices to support more sophisticated applications, specifically applications that call for extended data entry. As one interesting example, consider a recently introduced tablet-like detachable monitor supported by a host computing device, the host typically a personal computer (PC) sitting in a fixed location. The tablet has a touch-sensitive display screen. The tablet, once detached from the host, communicates wirelessly with the host and operates as a portable input/output device. A user carries the tablet around an office or home, using the tablet to gain access to applications running on the fixed-location host. Some of these applications, for example e-mail, word processing, and Web browsing, require extended text entry.
As experience with this tablet and with other increasingly capable portable devices has hinted, extensive data entry would be facilitated by a more robust data-entry mechanism than a stylus (or finger) on a virtual keyboard. Extensive typing on a virtual keyboard is a slow and tedious process, partly because a user must continually correct the position of his fingers over the keycap icons. A traditional hardware keyboard provides finger-positioning feedback via the indented surfaces of the keys. Touch-sensitive display screens are flat to allow good viewing, but their flatness does not provide such tactile feedback. As another hindrance to quick typing, these screens are also quite rigid with essentially no “give” to tell the user that a virtual key has been pressed.
Several attempts have been made to add a hardware keyboard to a small portable device, but none of these attempts has led to a satisfactory mechanism for extended data entry. One problem lies in the size of the hardware keyboard: full-size keyboards are cumbersome to carry around, detracting from the very portability that defines these devices, while smaller keyboards, useful for limited data-entry applications, do not comfortably accommodate the human hand to allow for rapid and extended typing.
What is needed is a way to make a touch-sensitive display screen into a more acceptable extended data-entry device. The utility of such a device would not be limited to portable display devices, but would enhance the experience of entering data on any touch-sensitive display screen.
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Form DPT-3 is the Return of Deposits, which is filed pursuant to Rule 16 of the Companies (Acceptance of Deposits) Rules. It states that every company to which such rule applies shall file on or before 30th of June of every year, with the Registrar a return of deposits or particulars of transaction which are not considered as deposits or both in Form DPT-3, along with the payment of the fees which has been prescribed or is applicable for the filing of the same and also furnish the information as on the last date of the FY ending on 31st of March of the relevant previous year as audited.
Say with respect to the FY 2019-20 which is ending on 31st March of 2020, the due date for filing form DPT-3 shall be 30th of June 2020.
What is Deposit?
As per section 2(31) of the Companies Act, deposits include any receipt of money by way of:
– a deposit, or
– a loan, or
– in such other valid form by a company.
It should also be noted that this does not include such categories of amount as may be prescribed in consultation with the Reserve Bank of India (RBI).
Who should File DPT-3?
The Ministry of Corporate Affairs (MCA) has made it mandatory for all the companies registered in India to file form DPT-3 and this would include:
– Private Limited Company
– Public Limited Company
– One Person Company (OPC)
The following companies are not required to file form DPT-3 or are given exceptions from the same:
– Government Company
– Banking Company
– Non-Banking Financial Corporation (NBFC)
– A Housing Finance Company which is formed asper the National Housing Bank
– Company which has NIL outstanding deposits/loans/amount not considered as deposits as of 31st March of the relevant financial year
– Any other company as it has been given or specified under proviso to the section 73(1) of the Companies Act.
Aim of Form DPT-3
The major objective for introducing form DPT-3 was to develop a one-time return, which would disclose or enable the company to declare the receipts considered as deposits and for receipts not given consideration as deposits referring to the provisions of the law or the Companies Act 2013.
And it shall be filed in two manners, and this includes:
– Time Return
– Annual Return.
The one-time return must be filed for a period which starts on 1st April 2014 to 31st March of 2019, where a reporting with regard to all receipts which are not considered as deposits but are received in this period and are outstanding as of 31st March 2019 should be made.
While the annual return is the period which starts from 1st of April 2019 to 31st March 2020 specifying the details of all the amounts which are outstanding as of such date.
Transactions that are not considered as Deposits
- Any amount received from the government or guaranteed given by the government, foreign government, or a foreign bank.
- Any amount received as a loan or facility from any Public Financial Institutions, Insurance Companies, or Banks.
iii. Any amount which is received from a company by another company.
- Subscription to securities and call-in advance amount received.
- Any amount received from the director of the company or a relative of the director of the Private company, who was holding such position at the time of lending.
- Any amount received by the company from an employee, not exceeding his annual salary under the employment contract such as a non-interest-bearing security deposit.
vii. Any monetary payment or such other amount received in the course of, or for the requirement of, the business of the company as an advance payment for the sale of goods or provision of services or for performing the contract, for the supply of goods or provision of services, in the form of a security deposit.
viii. Receipt of Rs 25 Lakh or more by a start-up company in the form of a convertible note, in a single tranche (group of securities).
- Amount raised by issuing secured bonds or debentures with first charge or non-convertible debentures which is not having a charge on the assets of the company.
- Unsecured loans received from promoters.
- Any monetary payment or such amount received by the company from either a Nidhi Company or by a manner of subscription in respect of chit which was made under the Chit Funds Act, 1982.
xii. Any amount received by the company from a collective investment scheme, alternate investment funds, or mutual funds registered with SEBI.
xiii. Any other amount which is not considered as a deposit under Rule 2(1)(c).
Information to be Furnished in Form DPT-3
The following details shall be furnished by a company in the form DPT-3:
– CIN of the company
– Email ID
– Objects of the company
– Net worth of the company
– Particulars related to the creation charge (if any)
– The total amount outstanding as of 31st of March 2020
– Particulars pertaining to the credit rating.
Documents to be Submitted
The following documents shall be submitted with MCA while filing form DPT-3:
– Auditor’s Certificate
– Copy of Trust deed
– As and where applicable or provided in the form, provide the contract of Deposit Insurance,
– Copy of instrument creating the charge
– List of depositors – List of deposits matured, and cheque issued but not yet cleared to be shown separately
– Details of liquid assets
– Such other optional attachments are specified in the form DPT-3.
Non-Filing of Form DPT-3
If the company fails to file form DPT-3 with the MCA and is accepting deposits contrary to the same then the following consequences shall arise pertaining to the Companies Act:
As per Section 73, a penalty of a minimum of INR 1 crore or twice the total amount of deposits whichever is lower, which may extend to INR 10 crore shall be levied.
For every officer who is in default, imprisonment up to 7 years and a fine not less than INR 25 Lakhs which may extend to INR 2 crores shall apply.
And in reference to the relevant Rule 21, on the company and every officer in default, there shall be a levy of a fine which may extend up to INR 5,000, and this shall be applied and where the contravention is a continuing one, a fine of INR 500 for every day since the default shall also be levied. | https://www.kanakkupillai.com/learn/why-and-who-should-file-dpt-3/ |
Peanut sitting on a stainless steel bench… along comes a rolling pin and… uh oh, nutter butter: peanut butter cookies filled with peanut butter frosting, a spoonful of peanut butter and salty caramel sauce. Toot toot!
Nutter butters
Australian Gourmet Traveller recipe for nutter butters from Sweet Envy.Aug 19, 2014 5:49am
- Serves 12
Ingredients
- 125 gm butter
- 100 gm caster sugar
- 100 gm soft brown sugar
- 1 egg, lightly beaten
- 225 gm pastry flour, sifted
- 1 tsp baking powder
- 70 gm peanuts
- 50 gm peanut butter, plus an extra 1 tsp for each biscuit
- ½ quantity of creamy vanilla frosting (see <b><u><a href="http://www.gourmettraveller.com.au/recipes/recipe-search/chefs-recipes/2014/8/creamy-vanilla-frosting">creamy vanilla frosting recipe</a></b></u>)
- 100 ml salty caramel (see <b><u><a href="http://www.gourmettraveller.com.au/recipes/recipe-search/chefs-recipes/2014/8/salty-caramel">salty caramel recipe</a></b></u>)
Method
Main
- 1Cream the butter and both sugars using electric beaters for about 5 minutes. Add the egg gradually until well mixed and pale and creamy. Add the sifted flour, baking powder and peanuts, being careful not to over-mix. Roll the dough into 2 logs, about 5cm in diameter. Cover with plastic wrap and freeze for about 1 hour until firm; the dough can be made ahead and frozen for several weeks. Thaw until firm before cutting and baking.
- 2Preheat the oven to 150C. Line 2 baking trays with baking paper. Cut the logs into 24 slices about 5mm thick, and space them apart on the baking trays, allowing room for a growth spurt in the oven. Bake for 10-15 minutes, or until an even golden brown. Remove from the oven and cool on the trays.
- 3Add the 50gm of peanut butter to the frosting and mix thoroughly. Pipe a ring of peanut butter frosting around the edge of half the biscuits. Place 1 tsp peanut butter in the centre of each, top with a spoonful of salty caramel and add a second biscuit as a lid. The biscuits will keep in an airtight container in a cool dark place for up to a week.
Notes
Note This recipe is from Sweet Envy ($45, hbk) by Alistair Wise and Teena Kearney-Wise, published by Murdoch Books, and has been reproduced with minor GT style changes. | https://www.gourmettraveller.com.au/recipes/chefs-recipes/nutter-butters-8126 |
Q:
If $\xi=kx$, does $\frac{d^{2}}{dx^{2}}=\frac{d^{2}}{d\xi^{2}}$
Let $\xi= kx$. Does $\dfrac{d^{2}}{dx^{2}}=\dfrac{d^{2}}{d\xi^{2}}$? If so, why? If not, what factor do I need to account for to make this change of variables?
A:
Let's try an example: $y = x^2$, so $\dfrac{d^2 y}{dx^2} = 2$. Now with $\xi = k x$ we have $x = \xi/k$, so $y = \xi^2/k^2$. Now what is $\dfrac{d^2 y}{d\xi^2}$?
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CROSS-REFERENCE TO RELATED APPLICATIONS
BACKGROUND
SUMMARY
DETAILED DESCRIPTION
This application claims priority under 35 U.S.C. § 119 of Korean Patent Application Nos. 10-2016-0135303, filed on Oct. 18, 2016, and 10-2017-0079978, filed on Jun. 23, 2017, the entire contents of which are hereby incorporated by reference.
The present disclosure herein relates to quantum computing, and more particularly, to a quantum circuit and method for implementing a heterogeneously encoded logical Bell state encoded with two different quantum error correction codes.
A quantum computer, based on qubits that are represented as a superposition of ‘0’ and ‘1’ using a principle of quantum mechanics, is known for performing a faster operation than a digital computer that handles bits capable of representing only ‘0’ or ‘1’. As a representative example showing excellent performance of a quantum computer, there is an integer factorization and a quantum mechanics simulation, etc. There are lots of attempts to implement a quantum computer using quantum mechanics, but it is very difficult to practically implement the quantum computer. A quantum noise issue is a representative example of the difficulty. A unique state that is inherent in quantum information may be easily lost by a small quantum noise. Therefore, fault-tolerant quantum error correction is used using a quantum error correction code for protecting the quantum information.
The fault-tolerant quantum information processing indicates that quantum information is encoded using a quantum error correction code and then the quantum information is operated using a quantum operator operating fault-tolerantly. Here, “fault-tolerant” means that even though a noise below a certain level occurs during information processing, the noise does not influence a final information processing result. The quantum information may be protected from the noise using the fault-tolerant quantum information processing based on the quantum error correction code.
On the other hand, the quantum computer may be configured of a plurality of components performing various functions. For example, there are a CPU for processing quantum information, a memory for storing the quantum information, and a bus for delivering information between the CPU and memory, etc. As currently known, since various quantum technologies have different characteristics and various quantum computer components have different functions and characteristics, it is necessary to combine the various quantum technologies for implementing a quantum computer.
Besides, quantum error correction codes having been suggested until now have different characteristics. Accordingly, for various purposes of quantum information processing in the quantum computer, it may be more effective to use multiple quantum error correction codes in combination, rather than a single quantum error correction code. In order to use various quantum error correction codes, it is essential to mutually convert different quantum error correction codes. A representative method thereof is a code teleportation. Using the code teleportation, pieces of quantum information encoded with different quantum error correction codes may be mutually converted into each other.
Until now, it has been suggested various quantum information processing protocols using the code teleportation. In order to use the code teleportation, a heterogeneously encoded logical Bell state is required in which encoding has been performed with two different quantum error correction codes desired to perform a conversion. However, a detailed method for implementing the heterogeneously encoded logical Bell state has rarely been discussed. Accordingly, in order to practically use the code teleportation, it is very important to implement the heterogeneously encoded logical Bell state.
The present disclosure provides a quantum circuit and method for implementing logical Bell states, which enable a mutual conversion between pieces of quantum information encoded by different quantum error correction codes.
An embodiment of the inventive concept provides a quantum circuit including: a Hadamard gating circuit configured to perform Hadamard conversions on a cat state; a controlled-NOT (CNOT) gating circuit configured to perform CNOT operations on first and second logical qubits encoded by first and second quantum error correction codes, respectively, and conversion results of the Hadamard gating circuit; a measuring circuit configured to measure calculation results of the CNOT gating circuit; and a logical bit converter configured to convert a bit of the second logical qubit on a basis of the measured result of the measuring circuit.
In an embodiments of the inventive concept, a method of operating a quantum circuit configured to a logical Bell state heterogeneously encoded by different quantum error correction codes, including: performing a Hadamard conversion on cat states; performing CNOT operations on a result of the Hadamard conversion and first and second logical qubits encoded by first and second quantum error correction codes, respectively; measuring results of the CNOT operations; and performing a conversion on a bit of the second logical qubit on a basis of the measured results.
In an embodiments of the inventive concept, a quantum circuit includes: first to third quantum circuits, each of which comprises a Hadamard gating circuit configured to perform Hadamard conversions on cat states, a CNOT gating circuit configured to perform CNOT operations on first and second logical qubits encoded by first and second quantum error correction codes, respectively, and conversion results of the Hadamard gating circuit, and a measuring circuit configured to measure calculation results of the CNOT gating circuit; a selection circuit configured to receive a measured result of the measuring circuit of each of the quantum circuits and select a target quantum state; and a logical bit converter configured to convert a bit of the second logical qubit output from the third quantum circuit on a basis of the selection result of the selection circuit.
Hereinafter, an exemplary embodiment of the present disclosure will be described in detail with reference to the accompanying drawings such that a person skilled in the art may easily carry out the embodiments of the present disclosure.
FIG. 1
FIG. 1
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is a block diagram schematically showing a quantum circuit according to an embodiment of the present inventive concept. Referring to , a quantum circuit may include a Hadamard gating circuit , a controlled-NOT (CNOT) circuit , a measuring unit , a parity detector , and a logical bit converter .
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The quantum circuit may generate a logical Bell state essentially required for code teleportation that enables a mutual conversion between pieces of quantum information encoded by different quantum error correction codes. For example, a physical Bell state may mean a quantum state in which two qubits are maximally entangled, and a logical Bell state may mean a quantum state in which each of two qubits in a physical Bell state is encoded with a quantum error correction code. In addition, a heterogeneously encoded logical Bell state proposed in the present inventive concept may mean a logical Bell state in which two qubits in a physical Bell state are respectively encoded using different quantum error correction codes. For example, the quantum circuit may generate an Eistein-Podolsky-Rose (EPR) pair as a logical Bell state.
100
The quantum circuit may receive a cat state having the length of nA+nB. For example, the cat state received by the quantum circuit may be defined as the following Equation (1).
nA+nB
⊗nA
⊗nB
⊗nA
⊗nB
|CAT>=|0>|0<+|1>|1>  (1)
where, nA is the block size of quantum error correction code A and nB is the block size of quantum error correction code B.
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The Hadamard gating circuit may be configured to perform a Hadamard conversion on the received cat state. For example, the Hadamard gating circuit may be configured to convert an individual qubit |0> or |1> in the cat state into a superposed state of a base state |0> or |1>. For example, the Hadamard gating circuit may be configured to perform the following Equations (2) and (3). In Equations (2) and (3), a subscript ‘H’ over arrows indicates Hadamard conversion.
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L
L
L
A
A
A
The quantum circuit may receive logical qubits encoded by different error correction codes. For example, the quantum circuit may receive a logical qubit |+>=(|0>+|1>)/√{square root over (2)} (or a positive quantum state) encoded by quantum error correction code A, and a logical qubit (or a positive quantum state) encoded by quantum error correction code B.
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L
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B
The CNOT gating circuit may perform CNOT operation on an output result of the Hadamard gating circuit and logical qubits |+>, |+>. The CNOT gating circuit may receive two qubits and output two output qubits, and calculates to convert one state of the received qubits according to the other state. For example, a first qubit of the received qubits may be a condition qubit C and a second qubit may be a target qubit T. For example, when the condition qubit is ‘0’, the CNOT gating circuit may maintain the input of the target qubit without a change. On the contrary, when the condition qubit is ‘1’, the CNOT gating circuit may perform a conversion on the input of the target qubit. The following table 1 represents a truth table of the CNOT gating circuit .
TABLE 1
Input
Output
C
T
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T
0
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
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L
nA+nB
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nA+nB
A
B
For example, by the CNOT gating circuit , a CNOT operation may be performed in a qubit unit for some qubits corresponding to a logical qubit |+>and code A of cat state |CAT>, and a CNOT operation may be performed in a qubit unit for the remaining qubits corresponding to a logical qubit |+>and code B of cat state|CAT>.
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L
L
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L
L
L
A
B
A
B
A
B
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B
The measuring unit may measure the calculation result of the CNOT gating circuit and output a classical bit (i.e. 0 or 1) according to the measured result. Signals in the drawing, which are output from the measuring unit , may represent classical bits and each arrow is represented with two lines. This is for distinguishing from an arrow with one line, which represents a qubit flow. For example, since the CNOT gating circuit is executed in a qubit unit, an output of the CNOT gating circuit may be configured of a combination of |0>|0>, |0>|1>, |1>|1>, and |1>|0>.
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For example, the measuring unit may measure a bit value of ‘0’ or ‘1’ of a qubit output from the CNOT gating circuit .
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L
B
The parity detector may receive an output result of the measuring unit to calculate a parity. For example, by the parity detector , when the number of ‘1’ of classical bits received from the measuring unit is determined as an odd number, an additional calculation may be performed on a logical qubit |+>by the logical bit converter . On the contrary, by the parity detector , when the number of ‘1’ of classical bits received from the measuring unit is determined as an even number, an additional calculation may be not performed by the logical bit converter .
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1
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L
L
L
x
x
B
B
B
i
i
The logical bit converter may perform a conversion on a bit of a logical qubit |+>. For example, when the number of ‘ ’ of classical bits received from the measuring unit is an odd number, the logical bit converter may reverse a bit of the logical qubit |+>. In Equation X=Πσ, the physical bit converter σrepresents performing a bit flip of using a Pauli matrix
<math overflow="scroll"><mrow><msub><mi>σ</mi><mi>x</mi></msub><mo>=</mo><mrow><mo>[</mo><mtable><mtr><mtd><mn>0</mn></mtd><mtd><mn>1</mn></mtd></mtr><mtr><mtd><mn>1</mn></mtd><mtd><mn>0</mn></mtd></mtr></mtable><mo>]</mo></mrow></mrow></math>
on a physical qubit i, which has a meaning like executing an X operation.
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L
L
L
L
A
B
A
B
When all the process including the conversion by the logical bit converter is completed, a heterogeneously encoded logical Bell state of an entangled state (i.e. an EPR pair in an entangled state) |0>|0>+|1>|1>may be generated.
FIG. 2
FIG. 1
shows in detail a configuration of the quantum circuit illustrated in .
110
110
L
L
A
B
The Hadamard gating circuit may include a plurality of Hadamard gates. For example, the Hadamard gating circuit may include the proper number of Hadamard gates so that a CNOT operation is performed on each qubit and logical qubits |+>,|+>configuring the cat state.
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L
L
A
B
The CNOT gating circuit may include a plurality of CNOT gates. Similarly, the CNOT gating circuit may include the proper number of CNOT gates so that a CNOT operation is performed on each qubit and logical qubits |+>,|+>configuring the cat state.
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The measuring unit may measure an output result of each CNOT gate configuring the CNOT gating circuit . For this end, the measuring unit may include measuring elements configured to measure an output result of each CNOT gate. For example, each measuring element configuring the measuring unit may measure a calculation result of the CNOT gate to output the same as a classical bit ‘0’ or ‘1’.
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L
L
B
B
The parity detector may determine whether an additional calculation is necessary for a qubit |+>. For example, when the number of ‘1’ of classical bits received from the measuring unit is an odd number, the parity detector may control a logical bit converter so that an additional calculation is performed on a logical qubit |+>.
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L
L
x
x
B
B
i
i
The logical bit converter may reverse the bit of the logical qubit |+>on the basis of the determination result of the parity detector . For example, the logical bit converter may be configured of a combination of a plurality of physical bit converters, and the combination may be differed according to a used quantum error correction code. In Equation X=Πσ, the physical bit converter σrepresents performing a bit flip of using a Pauli matrix
<math overflow="scroll"><mrow><msub><mi>σ</mi><mi>X</mi></msub><mo>=</mo><mrow><mo>[</mo><mtable><mtr><mtd><mn>0</mn></mtd><mtd><mn>1</mn></mtd></mtr><mtr><mtd><mn>1</mn></mtd><mtd><mn>0</mn></mtd></mtr></mtable><mo>]</mo></mrow></mrow></math>
L
L
B
B
150
on a physical qubit i, which has a meaning like executing an X operation. However, since the logical qubit |+>is ‘logically’ encoded by the quantum error correction code ‘B’, the logical bit converter is shown as X.
FIGS. 1 and 2
FIG. 3
100
L
L
L
L
A
B
A
B
However, the quantum circuit having been described in relation to is not fault-tolerant. In other words, it is not ensured that an EPR pair output from the quantum circuit is always |0>|0>+|1>|1>. The fault-tolerant quantum circuit will be described in detail in relation to .
FIG. 3
FIGS. 1 and 2
FIG. 1
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100
L
L
L
L
L
L
A
B
A
B
A
B
is a block diagram exemplarily showing a quantum circuit according to an embodiment of the present inventive concept. Unlike the quantum circuit having been described in relation to , a quantum circuit may be fault-tolerant. For example, logical qubits |+>,|>, the cat state, and the EPR pair input to the quantum circuit of are known quantum states in themselves. However, when the logical qubits |+>,|+>input to the quantum circuit and cat state have an error or a quantum state of the EPR pair output from the quantum circuit is not a desired state, it means there is an error. Accordingly, in this case, when the error of the logic qubits |+>,|+>input to the quantum circuit is corrected, or a cat state input to the quantum circuit is newly provided, an EPR pair without an error may be generated.
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FIGS. 1 and 2
L
L
B
B
The quantum circuit is substantially identical to the quantum circuit having been described in relation to . However, the quantum circuit is configured of multi-stages. For example, the quantum circuit may include a plurality of quantum circuits , , and . The quantum circuit may include quantum error correction circuits (QECs) , , , , , , and . The quantum circuit may receive parities respectively from the quantum circuits , , and , and include a selection circuit for determining whether to perform an additional calculation on the logical qubit |+>according to the received parities. The quantum circuit may include a bit converter for performing an additional calculation on the logical qubit |+>according according to the determination result.
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FIGS. 1 and 2
FIGS. 1 and 2
Each of the quantum circuits , , and may include the Hadamard gating circuit , the CNOT gating circuit , the measuring unit , and the parity detector having been described above in relation to . However, each of the quantum circuits , , and may not include the logical bit converter illustrated in .
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L
L
A
B
FIGS. 1 and 2
The first quantum circuit may receive logical qubits |+>,|+>and a cat state, and perform a series of operations such as a Hadamard conversion, CNOT gating operation, measurement, and parity calculation. Descriptions thereabout have been provided in relation to , and thus a detailed description will be omitted.
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Parity 1 output from the first quantum circuit may be delivered to the selection circuit . Even though it is illustrated in the drawing that parity 1 is delivered to the second quantum circuit , this is for clearness/simplification of the drawing. Logical qubits (shown as a and b in the drawing) output form the first quantum circuit may have an error or not. Accordingly, the quantum error correction circuits and may perform a quantum error correction on the logic qubits (shown as a and b in the drawing) output from the first quantum circuit . Quantum states of the logical qubits may be stabilized by the quantum error correction operation.
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The second quantum circuit may receive logical qubits (shown as c and d in the drawing) and a cat state from the quantum error correction circuits and , and perform a series of operations such as a Hadamard conversion, CNOT gating operation, measurement, and parity calculation.
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Parity 2 output from the second quantum circuit may be delivered to the selection circuit . Even though it is illustrated in the drawing that parity 2 is delivered to the third quantum circuit , this is for clearness/simplification of the drawing. Logical qubits (shown as e and f in the drawing) output from the second quantum circuit may have an error or not. Accordingly, the quantum error correction circuits and may perform a quantum error correction on the logic qubits (shown as e and fin the drawing) output from the second quantum circuit . Quantum states of the logical qubits may be stabilized by the quantum error correction operation.
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The third quantum circuit may receive logical qubits (shown as g and h in the drawing) and a cat state from the quantum error correction circuits and , and perform a series of operations such as a Hadamard conversion, CNOT gating operation, measurement, and parity calculation.
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Parity 3 output from the third quantum circuit may be delivered to the selection circuit . Logical qubits (shown as i and j in the drawing) output form the third quantum circuit may have an error or not. Accordingly, the quantum error correction circuits and may perform a quantum error correction on the logic qubits (shown as i and j in the drawing) output from the third quantum circuit . Quantum states of the logical qubits may be stabilized by the quantum error correction operation.
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The selection circuit may select a desired state (i.e. a target quantum state) having a quantum state without an error with reference to parity 1, parity 2, and parity 3 respectively received from the quantum circuits , , and . For example, when parity 1, parity 2, and parity 3 coincide with each other, this means that there is not an error in the calculation result by each of the quantum circuits , , and . On the contrary, when two of parity 1, parity 2, and parity 3 coincide with each other and the remaining one is different, this means that there is not an error in calculation operations by the two quantum circuits that output the two parities having the coincident values. In other words, a proper parity value may be selected by majority voting like this.
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FIGS. 1 and 2
When the proper parity value is selected by the selection circuit , the logical bit converter may perform an additional calculation. However, whether to perform the additional calculation may depend on the selected parity value, and since this has been described in detail in relation to , a description thereabout will be omitted.
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The logical bit converter may reverse a bit of the logical qubit (shown as i in the drawing) output from the quantum error correction circuit . The bit-reversed logical qubit (indicated as m in the drawing) may be delivered to the quantum error correction circuit .
252
The quantum error correction circuit may perform quantum error correction on the logical cubit (shown as m in the drawing) and as a result, a quantum state of the logical qubit may be stabilized.
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L
L
L
L
A
B
A
B
As a result, the logical qubits output from the quantum error correction circuits and may be a fault-tolerant logical Bell state (i.e. an entangled EPR pair) |0>|0>+|1>|1>.
FIG. 4
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schematically shows a code teleportation circuit using an EPR pair generated by a quantum circuit according to an embodiment of the present inventive concept. A code teleportation circuit may include a CNOT gate , a Hadamard gate , a first measuring unit , a second measuring unit , a first logical bit converter , and a second logical bit converter .
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L
L
A
B
The code teleportation circuit may convert quantum information |ψ>encoded with quantum error correction code A into quantum information |ψ>encoded with quantum error correction code B.
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L
L
L
L
A
B
A
B
A
FIGS. 1 and 3
First, the code teleportation circuit may perform a CNOT operation on the EPR pair |0>|0>+|1>|1>and the quantum information |ψ>output from .
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L
A
The Hadamard gate may perform a Hadamard conversion on the received quantum information |ψ>. The Hadamard conversion may be performed according to the above-described Equations (2) and (3).
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The first measuring unit may measure an output result of the Hadamard gate . For example, when the number of classical bits ‘1’ is an odd number among the output results of the Hadamard gate , the first measuring unit may output logical qubit ‘1’. On the contrary, when the number of classical bits ‘1’ is an even number among the output results of the Hadamard gate , the first measuring unit may output logical qubit ‘0’.
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The second measuring unit may measure an output result of the CNOT gate . For example, when the number of classical bits ‘1’ is an odd number among the output results of the CNOT gate , the second measuring unit may output logical qubit ‘1’. On the contrary, when the number of classical bits ‘1’ is an even number among the output results of the CNOT gate , the second measuring unit may output logical qubit ‘0’.
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L
L
L
L
A
B
A
B
FIGS. 1 and 2
FIG. 3
The first logical bit converter may perform an additional calculation in dependence of an output result from the second measuring unit . For example, when a logical qubit output from the second measuring unit is ‘1’, the first logical bit converter may perform a logical bit conversion on a logical qubit corresponding to code B of the EPR pair |0>|0>+|1>|1>. This may be similar to operation of the logical bit converter having been described in relation to , or an operation of the logical bit converter having been described in relation to .
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The second logical bit converter may perform an additional calculation in dependence of an output result from the second measuring unit . For example, when a logical qubit output from the first measuring unit is ‘1’, the second logical bit converter may perform a logical bit conversion on an output result of the first logical bit converter .
l
B
360
As a result, quantum information ★ψ>encoded with quantum error correction code B may be output from the second logical bit converter .
FIG. 5
L
L+1
schematically shows a state injection circuit for converting quantum information |ψ>encoded in a concatenation level L into quantum information |ψ>in the concatenation level L+1.
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The state injection circuit may include a first CNOT gate , a decoder , a second CNOT gate , a Hadamard gate , a first measuring unit , a second measuring unit , a first logical bit converter , and a second logical bit converter .
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L+1
L+1
L+1
L
L
L
The first CNOT gate may perform a CNOT operation on logical qubits |+>and |0>. The decoder may decode the logical qubit |+>to generate a logical qubit in a concatenation level L. The second CNOT gate may perform a CNOT operation on quantum information |ψ>and the logical qubit |+>. The Hadamard gate may perform a Hadamard conversion on the quantum information |ψ>.
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The first measuring unit may measure a logical bit value of an output from the Hadamard gate . For example, when the number of classical bits ‘1’ is an odd number among the output results of the Hadamard gate , the first measuring unit will output logical qubit ‘1’. The second measuring unit may measure a logical bit value of an output from the second CNOT gate . For example, when the number of classical bits ‘1’ is an odd number among the output results of the second CNOT gate , the second measuring unit will output logical qubit ‘1’.
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FIGS. 1 and 2
FIG. 3
The first logical bit converter may perform an additional calculation in dependence of an output result from the first measuring unit . For example, when a logical qubit output from the second measuring unit is ‘1’, the first logical bit converter may perform a logical bit conversion on a third logical qubit in the drawing. This may be similar to an operation of the logical bit converter having been described in relation to , or an operation of the logical bit converter having been described in relation to .
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The second logical bit converter may perform an additional calculation in dependence of an output result from the second measuring unit . For example, when a logical qubit output from the first measuring unit is ‘1’, the second logical bit converter may perform a logical bit conversion on an output result of the first logical bit converter .
L+1
As a result, quantum information |ψ>in a recursive (L+1)-th step may be generated.
FIG. 6
500
is a block diagram exemplarily showing a quantum circuit according to an embodiment of the present inventive concept. A quantum circuit may implement a heterogeneously logical Bell state encoded in an arbitrary concatenation level (i.e. n-th step).
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51
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521
52
m
m
m
m
FIG. 5
The quantum circuit may include a plurality of state injection circuits to and to . The state injection circuits to and to are substantially identical to that having been described in relation . Therefore repeated descriptions will be omitted.
511
51
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m
m
L=1
L=n
L=1
L=n
A
A
B
B
The state injection circuits to may be configured to convert quantum information |ω>of a recursive first step, which is encoded with quantum error correction code A, into quantum information |ω>of a recursive n-th step. Similarly, the state injection circuits to may be configured to convert quantum information |ψ>of a recursive first step encoded with quantum error correction code A into quantum information |ω>of a recursive n-th step.
According to embodiments described above, pieces of quantum information encoded with different quantum error correction codes may be mutually freely converted. Since a general purpose information processing equipment (e.g. a quantum computer etc.) performs various functions, the equipment may be configured of a plurality of components. Accordingly, it may be easier to implement the general purpose information processing equipment using a quantum code conversion technology according to an embodiment of the present inventive concept.
According to an embodiment of the present inventive concept, a quantum circuit and method for implementing a logical Bell state may be provided, which enable mutual conversion between pieces of quantum information encoded with different quantum error correction codes.
The foregoing description is about detailed examples for practicing the inventive concept. The present disclosure includes not only the above-described embodiments but also simply changed or easily modified embodiments. In addition, the inventive concept may also include technologies obtained by easily modifying and practicing the above-described embodiments.
The above-disclosed subject matter is to be considered illustrative and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments, which fall within the true spirit and scope of the inventive concept. Thus, to the maximum extent allowed by law, the scope of the inventive concept is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.
BRIEF DESCRIPTION OF THE FIGURES
The accompanying drawings are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the inventive concept and, together with the description, serve to explain principles of the inventive concept. In the drawings:
FIG. 1
is a block diagram schematically showing a quantum circuit according to an embodiment of the present inventive concept;
FIG. 2
FIG. 1
shows in detail a configuration of the quantum circuit illustrated in ;
FIG. 3
is a block diagram exemplarily showing a quantum circuit according to an embodiment of the present inventive concept;
FIG. 4
schematically shows a code teleportation circuit using an
Eistein-Podolsky-Rose (EPR) pair generated by a quantum circuit according to an embodiment of the present inventive concept;
FIG. 5
schematically shows a state injection circuit; and
FIG. 6
is a block diagram exemplarily showing a quantum circuit according to an embodiment of the present inventive concept. | |
The utility model provides an electric white board eraser. A bottom box is fixed to the bottom of a white board, a small left motor and a small left eraser are installed on the upper left corner of the white board, a small right motor and a small right eraser are installed on the upper right corner of the white board, a battery is installed in the middle of the bottom box, a large left motor and a large left eraser are installed on the left side of the battery, a large right motor and a large right eraser are installed on the right side of the battery, a resistor is installed on the left side of the bottom box, and a large left eraser switch, a large right eraser switch, a small left eraser switch, a small right eraser switch and a speed switch are installed on the right side of the bottom box. The large left motor and the large right motor are autotruck windscreen wiper motors, and the small left motor and the small right motor are car windscreen wiper motors. The content on the white board can be removed by a teacher through any one of the four switches according to requirements in class, the content can be written on the white board and can be erased at any time in class, and can be completely removed after class by switching on the four switches at the same time, the erasing speed can be adjusted through the speed switch according to requirements, and therefore the electric white board eraser is flexible, convenient to use and practical. | |
How to volunteer during the COVID-19 outbreak
We need volunteers to prepare and serve to-go meals Monday to Saturday, three meals a day. Volunteers shifts are 6-7:30 am; 11 am-12:30 pm, and 4:30-6 pm. Volunteers cannot have exhibited within 72 hours any COVID-19 related symptoms, such as sore throat, cough, shortness of breath, and/or fever, or been exposed to someone who has exhibited symptoms. Persons age 60 or older or who have high-risk health conditions are encouraged not to volunteer at our facility.
Step 1: Email your availability to [email protected].
Step 2: Fill out a profile so we can communicate with you.
Step 3: Sign a waiver upon arrival.
Ways to help from the safety of your home
Do you, your family or friends want to help alleviate suffering while you’re at home? Read our page of ideas for how to get involved from home.
About Volunteering
We welcome you to serve meals, plate food or bus tables in our Founders Cafe. Our public cafe is a clean and safe environment where anyone in need of a meal can find one without judgment. We are dedicated to serving all of our guests with dignity and respect. Read the volunteer handbook.
Please note:
- Volunteers must be at least 12 years old.
- We can only accommodate up to 12 volunteers per meal. If you have a larger group email us at [email protected].
- We do not allow photos of our meal guests or residents. Please respect the privacy of those we serve.
- Groups must fill out group sign up form
- All volunteers must sign a waiver and provide emergency contact
- We cannot accommodate court ordered service at this time.
Long time Blanchet House volunteer, Linda Wabs, explains why she likes to serve in our Founders Cafe.
Step 1. Create a volunteer profile by clicking the orange ‘New & Returning Volunteers’ button
Step 2. Choose a breakfast, lunch or dinner shift from the volunteer calendar. Click the ‘Volunteer Calendar’ button.
Step 3. Print waiver if you are a minor. Sign and bring on volunteer date. Adults can checkbox online.
Want to sign up your group? Click the ‘Group Sign Up’ button.
Our Volunteer Coordinator
Meet Brittany Brock our Volunteer Coordinator and a Jesuit Volunteer/Americorps member. She will spend the next year welcoming, scheduling and training all of our volunteers. If you have any questions about volunteering please contact her at the email below.
Contact [email protected]
New Volunteer Opportunity!
We need volunteers to sort and label clothing donations to be handed out to our meal guests and residents.
Estimated Time: 1 hour
Choose a volunteer window: 9:00 to 10:00 am or 2:00 to 3:00 pm Click here to sign up. | https://blanchethouse.org/Volunteer/ |
But I don’t code in python!¶
We’ve made every effort to make sure that you can still use Rasa Core even if you don’t want to use python. However, do consider that Rasa Core is a framework, and doesn’t fit into a REST API as easily as Rasa NLU does.
Rasa Core with minimal Python¶
You can build a chatbot with Rasa Core by:
- defining a domain (a yaml file)
- writing / collecting stories (markdown format)
- running python scripts to train and run your bot
The only part where you need to write python is when you want to define custom actions. There’s an excellent python library called requests, which makes HTTP programming painless. If Rasa just needs to interact with your other services over HTTP, your actions will all look something like this: | https://core.rasa.com/no_python.html |
We have 436 rolls of film from Christian County. That's about 15,306 photos.
74% of our collection is searchable in this county. If you don't find what you're looking for, try browsing our entire archive.
Search Keywords
Search names, comments, and tags left by visitors or photo numbers (e.g., 1-ABC-2)
County Leaderboard
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74,659 total points1,368
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11,970 total points564
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252 total points199
Unidentified Rolls
Not all film in this county had flight maps. We need your help identifying them!
19%
100 rolls to go!
23 of 123 rolls without maps found by our community
Most Viewed Photos
Latest Comments
44-JCR-8
1971
29
1
We bought the farm in 1988. At the time we purchased the farm the animal pens had changed and the small building... more »
50-ACH-24
1967
46
1
Grew up in second house on the right, 327 N. Locust Streer. First house on the right is gone.
17-HCH-27
1970
48
1
Motel formerly on Rt 51 south of Pada. Very similar in design to the Lake Lawn Inn east of town. | https://vintageaerial.com/photos/illinois/christian |
•Before developing an eLearning program, it is important to have a detailed plan that includes the goals of the program, who the target audience is, and what Learning Management System will be used.
• It is crucial to coordinate with your IT department when developing your eLearning program in order to create a secure environment.
• A safe eLearning environment requires strong authentication measures such as requiring learners to use strong passwords and additional verification codes when logging in from new devices.
• In order to protect sensitive user data, you should have clear compliance policies in place that are communicated to your learners. Your LMS should also allow you choose settings that comply with specific industry regulations.
• To avoid costly fines or data breaches, it is essential to perform regular risk assessments and maintain accurate records of any compliance issues.
• Encrypting all data within the eLeaning environment protects information from unauthorized access while it transit or at rest.. | https://mbruceabbott.com/tips-for-creating-a-safe-and-secure-elearning-environment/ |
Q:
Application of derivatives.
In a distance of 2 meters from a lantern, we let a ball fall. After a second, which is the velocity of the shadow of the ball?. If $y$ is the position of the ball in function of time.
$y(t)=12-4.9t^2$
By similarity of triangles,
$\frac{y}{x}=\frac{12}{x+2}$
Therefore, $x=\frac{2y(t)}{12-y(t)}\implies \frac{dx}{dt}=\frac{24\frac{dy}{dt}}{(12-y)^2}$.
I don't understand this implication, can anyone explain it step by step, I would appreciate it a lot.
$x(t)'=(2y(t))'(12-y(t))^{-1}+(2y(t))((12-y(t))^{-1})'=\frac{24-9.8t^2}{12-y(t)}+\frac{-(24-9.8t^2)}{-4.9t^4}$....
I am probably doing too many things wrong, excuse me please..
A:
Let's rewrite the quotient as a product, so: $$x(t)=2y\left( 12-y\right)^{-1}$$
Of course $y=y(t)$.
Differentiate via the product rule to get $$x'(t)=\frac {2y'}{12-y}-\frac {2y}{(12-y)^2}\times \frac d{dt}(12-y)=\frac {2y'}{12-y}+\frac {2yy'}{(12-y)^2}$$
All that remains to put the two terms over a common denominator, namely $(12-y)^2$: $$x'(t)=\frac {2y'(12-y)+2yy'}{(12-y)^2}=\frac {24y'}{(12-y)^2}$$ as desired.
| |
___Unless provided otherwise in this part, no person having actual knowledge of the death of a decedent shall enter a safe deposit box of the decedent. This part shall not be construed to confer upon any person any right of entry into a safe deposit box of a decedent which he does not otherwise have.
Section 2192. Entry Without Notice to Department.
___(a) A safe deposit box of a decedent may be entered and any or all of the contents removed in the presence of an employee of the financial institution in which the box is located. The employee shall make, or cause to be made, a record of the contents of the box, which record he shall attest under penalty of perjury to be correct and complete. The financial institution may make a reasonable charge for the attendance of its employee at the entry of the box and the listing of the contents, which charge shall be deductible as an administration expense under subclause (1) of section 2127.
___(b) A safe deposit box of a decedent may be entered and any or all of the contents removed in the presence of a representative of the department authorized by the Secretary. The department shall authorize at least one such representative in and for each county of this Commonwealth. The representative present at the time of entry into the box shall make or cause to be made a record of the contents of the box.
___(c) The court for cause shown may order that a designated person or persons be permitted to enter a safe deposit box of a decedent and remove the contents described in the order, under supervision as the court may direct. The order may also require that a record be made of the contents of the box.
___(d) Notwithstanding any of the provisions of this part, the department, at any time and without relation to the death of a specific decedent, by a certificate issued to a firm whose business requires ready access to safe deposit boxes, may issue a general authorization for the entry into, and removal of the contents of, a safe deposit box of a decedent, under terms and conditions as it may prescribe. A financial institution may permit such entry and removal upon presentation to it of such certificates issued by the department.
___(e) Nothing in this part shall prohibit a financial institution from permitting entry into a safe deposit box of a decedent for the sole purpose of removing the decedent's will and evidence of ownership of the burial lot in which the decedent is to be interred. An employee of the financial institution must be present at the opening of the box and make or cause to be made a record of the documents removed from the safe deposit box during the entry and attest the record to be correct and complete under penalty of perjury.
Section 2193. Entry Upon Notice to Department.
___(a) When entry into a safe deposit box of a decedent is not or cannot be made under the provisions of subsection (a), (b), (c) or (d) of section 2192, a safe deposit box of a decedent may be entered at the time fixed in a notice mailed to the Department of Revenue, Harrisburg, Pennsylvania, and to the financial institution in which the box is located, in the manner specified in this section. The date fixed for entry and contained in the notice shall not be less than seven days after the date of notice is mailed. A representative of the department may be present at the time fixed for entry and may make or cause to be made a record of the contents of the box.
___(b) The notice required under subsection (a) shall be delivered to the United States Postal Service for mailing in a manner that will provide for a record of the mailing being made by the United States Postal Service and a receipt being furnished to the sender. An exact copy of the notice shall be transmitted to the financial institution in which the box is located.
___(c) At the time fixed in the notice required by subsection (a), although no representative of the department is present, it shall be lawful for a financial institution in which a safe deposit box of a decedent is located to permit, and it shall permit, entry into the box and removal of its contents by a person who furnishes a signed statement under penalty of perjury that he or someone in his behalf has given such notice.
___Nothing in this part shall be construed to impose any restriction upon reentry into a safe deposit box of a decedent at any time subsequent to an entry made in accordance with any of the provisions of this part other than subsection (e) of section 2192.
Section 2195. Confidential Nature of Contents.
___Any information gained from the contents of a safe deposit box of a decedent by a person whose attendance at the entry into the box was required by this part shall be confidential and shall not be disclosed for other than official purposes to collect the taxes imposed by this article.
___(a) Any employee of a financial institution in which the safe deposit box of a decedent is located who, having actual knowledge of the death of the decedent, enters or permits the entry by any person into a safe deposit box of the decedent in violation of the provisions of this part commits a misdemeanor of the third degree.
___(b) Any person, other than an employee of a financial institution in which the safe deposit box of a decedent is located, who, having actual knowledge of the death of a decedent, enters a safe deposit box of the decedent in violation of the provisions of this part commits a misdemeanor of the third degree.
___(c) Any person who violates the provisions of section 2195 commits a misdemeanor of the third degree. | http://evans-legal.com/dan/ieta/a21p12.html |
Q:
Pass subquery value to IN statement
In one table named prefs, I have a column named "Value" of type clob that holds this value: 'T', 'L'
I need to query table attendance_code to retrieve the records where column att_code values are either T or L. The att_code column is of type varchar2.
As a manual model query, this works fine:
SELECT id FROM attendance_code ac WHERE ac.att_code IN ('T', 'L')
Result:
ID
1 4903
2 4901
Attempt 1
SELECT id FROM attendance_code ac WHERE ac.att_code IN (SELECT value from prefs WHERE name = 'AEADS|SAR|tdyCodes')
ORA-00932: inconsistent datatypes: expected - got CLOB
00932. 00000 - "inconsistent datatypes: expected %s got %s"
Attempt 2
SELECT id FROM attendance_code ac WHERE ac.att_code IN (SELECT dbms_lob.substr(value, 4000, 1) from prefs WHERE name = 'AEADS|SAR|tdyCodes')
This yields no error, but returns no rows.
Attempt 3
(Based on https://blogs.oracle.com/aramamoo/how-to-split-comma-separated-string-and-pass-to-in-clause-of-select-statement)
select id from attendance_code ac where ac.att_code IN (
select regexp_substr(value,'[^,]+', 1, level) from prefs WHERE name = 'AEADS|SAR|tdyCodes'
connect by regexp_substr(value, '[^,]+', 1, level) is not null );
ORA-00932: inconsistent datatypes: expected - got CLOB
00932. 00000 - "inconsistent datatypes: expected %s got %s"
Attempt 4
select id from attendance_code ac where ac.att_code IN (
select regexp_substr(dbms_lob.substr(value, 4000, 1),'[^,]+', 1, level) from prefs WHERE name = 'AEADS|SAR|tdyCodes'
connect by regexp_substr(dbms_lob.substr(value, 4000, 1), '[^,]+', 1, level) is not null );
ORA-06502: PL/SQL: numeric or value error: character string buffer too small
ORA-06512: at line 1
06502. 00000 - "PL/SQL: numeric or value error%s"
*Cause: An arithmetic, numeric, string, conversion, or constraint error
occurred. For example, this error occurs if an attempt is made to
assign the value NULL to a variable declared NOT NULL, or if an
attempt is made to assign an integer larger than 99 to a variable
declared NUMBER(2).
*Action: Change the data, how it is manipulated, or how it is declared so
that values do not violate constraints.
I have also tried changing the value in the prefs table to just T,L (removing the single quotes) and running all of the above against that, to no avail.
What is the proper way to do this, please?
A:
You can use hierarchical query with removed single quotes as follows:
SELECT ID
FROM ATTENDANCE_CODE AC
WHERE AC.ATT_CODE IN (
SELECT
REPLACE(TRIM(REGEXP_SUBSTR(
(SELECT value from prefs WHERE name = 'AEADS|SAR|tdyCodes'),
'[^,]+', 1, LEVEL)), '''', '') FROM DUAL
CONNECT BY REGEXP_SUBSTR(
(SELECT value from prefs WHERE name = 'AEADS|SAR|tdyCodes'),
'[^,]+', 1, LEVEL) IS NOT NULL
);
or simplify the above query with the CTE as following:
WITH DATAA ( VALS ) AS (
SELECT VALUE
FROM PREFS
WHERE NAME = 'AEADS|SAR|tdyCodes'
)
SELECT ID
FROM ATTENDANCE_CODE AC,
DATAA D
WHERE AC.ATT_CODE IN (
SELECT
REPLACE(TRIM(REGEXP_SUBSTR(D.VALS, '[^,]+', 1, LEVEL)), '''', '')
FROM DUAL
CONNECT BY
REGEXP_SUBSTR(D.VALS, '[^,]+', 1, LEVEL) IS NOT NULL
);
Example with Dual as following:
SQL> SELECT DUMMY FROM DUAL AC
2 WHERE
3 'T' IN (
4 SELECT
5 REPLACE(TRIM(REGEXP_SUBSTR(
6 (SELECT q'#'T', 'L'#' FROM DUAL), '[^,]+', 1, LEVEL)), '''', '')
7 FROM DUAL
8 CONNECT BY
9 REGEXP_SUBSTR((
10 SELECT q'#'T', 'L'#' FROM DUAL), '[^,]+', 1, LEVEL) IS NOT NULL
11 );
DUMMY
-------
X
SQL>
Cheers!!
| |
Design, 300 million euros more for local authoritiesThe Budget Law adds 300 million euros to the Fund for the definitive and executive planning of the Municipalities, established by the Budget Law for 2020. The Fund was established with a time horizon up to 2031 and an initial endowment of € 2.2 billion. With the new injection of resources, ordered by the Budget Law for 2022, the budget reaches 2.5 billion euros.
The 2022 Budget Law also modifies the priorities to be followed for the allocation of resources, favoring the works financed by the PNRR. According to the Budget Law for 2020, the priorities were hydrogeological risk, the safety of roads, bridges and viaducts, the safety and efficiency of the buildings of local authorities, schools in the first place.
With the news of the 2022 Budget Law, therefore, the resources will be assigned as a priority to the planning of the following interventions:
a) public works in the context of PNRR;
b) securing the territory a hydrogeological risk;
c) securing of roads, bridges and viaducts;
d) securing ed energy efficiency of buildings, with priority for school buildings, and of other structures owned by the Bodies.
Local authorities must send the requests by 15 March 2022 and the Ministry of the Interior will draw up the ranking by April 15, 2022.
The Budget Law assigns to Municipalities 300 million euros, 200 million euros for 2022 and 100 million euros for 2023, for the extraordinary maintenance of municipal roads, sidewalks and street furniture.
Extraordinary road maintenance, 300 million to the municipalities
Municipalities are entitled to these resources provided that such works are not already fully funded by other subjects and which are additional to those envisaged in the second and third annuities of the 2021-2023 budget.
The contributions for the year 2022 will be assigned by the Ministry of the Interior by January 15, 2022 and they will be commensurate with the inhabitants:
– up to 5,000 inhabitants> 10,000 euros;
– between 5,001 and 10,000 inhabitants> 25,000 euros;
– between 10,001 and 20,000 inhabitants> 60,000 euros;
– between 20,001 and 50,000 inhabitants> 125,000 euros;
– between 50,001 and 100,000 inhabitants> 160,000 euros;
– between 100,001 and 250,000 inhabitants> 230,000 euros;
– over 250,000 inhabitants> 350,000 euros.
The reference population for the purposes of the allotment is that resident as of December 31, 2019 post census.
I contributions for the year 2023 will be awarded in measure equal to half of the contribution assigned for 2022.
The work will have to begin by 30 July 2022 for contributions relating to the year 2022 and by 30 July 2023 for contributions relating to 2023.
Source: Le ultime news dal mondo dell'edilizia by www.edilportale.com.
*The article has been translated based on the content of Le ultime news dal mondo dell'edilizia by www.edilportale.com. If there is any problem regarding the content, copyright, please leave a report below the article. We will try to process as quickly as possible to protect the rights of the author. Thank you very much!
*We just want readers to access information more quickly and easily with other multilingual content, instead of information only available in a certain language.
*We always respect the copyright of the content of the author and always include the original link of the source article.If the author disagrees, just leave the report below the article, the article will be edited or deleted at the request of the author. Thanks very much! Best regards! | https://tekdeeps.com/300-million-to-local-authorities-for-planning/ |
Let’s discuss the question: how much pounds is 16 ounces. We summarize all relevant answers in section Q&A of website Myyachtguardian.com in category: Blog MMO. See more related questions in the comments below.
Does 16 ounces equal 1 pound?
There are 16 ounces in 1 pound. Learn to convert pounds to ounces.
Is 16 oz half a pound?
|Ounces||Pounds|
|13 oz||0.81 lb|
|14 oz||0.88 lb|
|15 oz||0.94 lb|
|16 oz||1.00 lb|
How to Measure Ounces and Pounds
Images related to the topicHow to Measure Ounces and Pounds
Is 8 oz the same as 1 lb?
8 oz. are equal to 12 pounds.
Does 16oz equal 2 cups?
16 oz = 2 cups
You may also be interested to know that 1 oz is 1/8 of a cup. Thus, you can divide 16 by 8 to get the same answer.
How many 16 fl oz make a gallon?
Answer: 8 bottles of 16 oz are required to make one gallon.
Let us understand the relationship between ounces and gallons.
How do I calculate pounds?
- Pound (lbs) / 2.2046 = Result in Kilograms (kg)
- Kilograms (kg) x 2.2046 = Result in Pound (lbs)
- 100 pounds (lbs) / 2.2046 = 45,36 kilos (kg)
- 100 kilos (kg) * 2.2046 = 220,46 pounds (lbs)
Is 8 oz half a pound?
|Ounces (oz)||Pounds (lb)||Pounds+Ounces (lb+oz)|
|8 oz||0.5 lb||0 kg 226.80 g|
|9 oz||0.5625 lb||0 kg 225.15 g|
|10 oz||0.625 lb||0 kg 283.50 g|
|20 oz||1.25 lb||0 kg 566.99 g|
How much pounds are in a gallon?
1 Gallon = 8.34 Lbs.
What is half of 1 pound?
a unit of weight equal to 8 ounces avoirdupois (0.227 kilogram) or 6 ounces troy or apothecaries’ weight (0.187 kilogram).
What is oz weight?
ounce, unit of weight in the avoirdupois system, equal to 1/16 pound (437 1/2 grains), and in the troy and apothecaries’ systems, equal to 480 grains, or 1/12 pound. The avoirdupois ounce is equal to 28.35 grams and the troy and apothecaries’ ounce to 31.103 grams.
Converting Ounces and Pounds
Images related to the topicConverting Ounces and Pounds
How many ounces are in a pound of powder?
One pound of powdered sugar converted to ounce equals to 16.00 oz.
How do you measure 16 ounces?
In the US a standard cup measure = 8 FLUID oz (abbrev. fl. oz) of VOLUME. If by 16 oz you mean the US VOLUME, equal to 1 PINT US, then 2 cups.
How many dry cups is 16 oz?
|3 teaspoons||1 tablespoon||1/2 ounce|
|5 1/3 tablespoons||1/3 cup||2.6 fluid ounces|
|8 tablespoons||1/2 cup||4 ounces|
|12 tablespoons||3/4 cup||6 ounces|
|32 tablespoons||2 cups||16 ounces|
How do I measure 16 oz of powdered sugar?
Powdered sugar right out of the box or the plastic bag weighs 4 1/2 ounces per cup, so a 1-pound box (or 16 ounces) contains about 3 1/2 cups of powdered sugar. If a recipe calls for sifted powdered sugar, weigh out 4 ounces of sifted powdered sugar to equal 1 dry measuring cup.
How many quarts is 16 ounces?
|Fluid Ounces||Quarts|
|16||0.5|
|24||0.75|
|32||1|
|40||1.25|
How many 16 oz are in a half gallon?
There are 128 fluid ounces in 1 liquid gallon. If you divide 128 by 16 you will get 8, so it would take eight 16 fluid ounces to fill 1 liquid gallon.
How many bottles of 16 oz water should I drink a day?
Because there are 8 fluid ounces in a cup, you should drink eight cups of water per day. Most disposable water bottles are around 16 ounces, so that would mean you should drink three to four bottles of water each day.
Is lb same as pound?
“Pound” and “lbs.” are essentially the same thing. The pound is the actual unit of measurement, while “lbs.”, which stands for libra, is the common abbreviation used in expressing pounds. The correct way of abbreviation in expressing singular or plural pounds is “lb.” 3.
Ounces , Pounds, \u0026 Tons Song ★ Customary Units of Measurement
Images related to the topicOunces , Pounds, \u0026 Tons Song ★ Customary Units of Measurement
What is the meaning of 1 lbs?
Pound. Definition: A pound (symbol: lb) is a unit of mass used in the imperial and US customary systems of measurement. The international avoirdupois pound (the common pound used today) is defined as exactly 0.45359237 kilograms. The avoirdupois pound is equivalent to 16 avoirdupois ounces.
Is pound IB or lb?
The international standard symbol for the avoirdupois pound is lb; an alternative symbol is lbm (for most pound definitions), # (chiefly in the U.S.), and ℔ or ″̶(specifically for the apothecaries’ pound). The unit is descended from the Roman libra (hence the abbreviation “lb”).
Related searches
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Information related to the topic how much pounds is 16 ounces
Here are the search results of the thread how much pounds is 16 ounces from Bing. You can read more if you want.
You have just come across an article on the topic how much pounds is 16 ounces. If you found this article useful, please share it. Thank you very much. | https://myyachtguardian.com/how-much-pounds-is-16-ounces-update/ |
Arrival:
Bavella is located in the south-hinterland of Corsica and to reach it you have to reach the small city of Zonza. Get to the roundabout in the middle of Zonza (street lamp) then take the exit to Col de Bavella / Bocca di Bavedda. Now you have to keep driving along the D268 and after 8.7 km you will get to the destination. There are many car parks, both on the right and left side of the road.
Sectors:
The summits of Bavella are clearly visible from the car park. The topo collects all the trails to the different sectors.
Brief explanations of the paths (refer to the purple trail of the topo).
In front of the first car park there is the “Notre Dame des Neiges” grouping crucifixes and a Madonna. Walk along the fence of this interdicted area, Zonza direction, then at its end turn right (red-white paint on a rock). Walk on the main path for about 260, till you get to a junction.
Go left if you want to reach Talavellu sector. In this case walk for other 120 meters, then go right towards the two small walls that will be visible.
Otherwise, keep the right and proceed along the main path for 160 meters and you will get to an area with many intersections.
Filetta, Margherita, La Tarella, Grande Dalle and Noca:
Take the path on the right that leads to the slabs of Filetta and Margherita after about 90 meters.
La Tarella is few meters ahead and Grande Dalle is just above the previous walls. To reach Noca, go over La Tarella and follow the path for something more than 30 meters.
Campanella, Paterla nera and Orìu:
Go straight on towards the clearly visible wall of Orìu. After 40 meters you will find the path towards Campanella and Paterla nera on the right. Campanella is 80 meters ahead and is in front of Paterla Nera. To reach Orìu, do not turn right but continue walking towards the huge wall (90 meters).
Punta Picchiaddu:
Keep the left after the junctions area and follow the path for over 350 meters. The sector will not be visible until you get there. Some reference along the way: cross the Variante Alpine of the GR20, traverse on rocky crest then a bit downhill for about 200 meters, go down the dry stream bed and at the large tree go right and climb till the rocky spur. | https://27crags.com/crags/bavella/access |
Delicious toasty character with body reminiscent of Oolongs. Lingering taste that encourages another cup.
Ingredients: White tea
IDEAL BREWING TEMPERATURE: 85ºC/185ºF. For Food Safety reasons bring water to 100ºC/212ºF and let it cool down to 85ºC/185ºF.
This tea contains a low level of caffeine | Steep at 212° for 3-5 minutes. | https://dreamingoftea.com/products/dreamy-sowmee-white-tea |
The Climate Modeling Initiative is an open-source collaborative based at MIT which has developed a modeling infrastructure for the study of the atmosphere, ocean and climate of the Earth.
How are climate models created?
Climate models include more atmospheric, oceanic and land processes than weather models do—such as ocean circulation and melting glaciers. These models are typically generated from mathematical equations that use thousands of data points to simulate the transfer of energy and water that takes place in climate systems.
What are climate models based on?
Climate models are based on global patterns in the ocean and atmosphere, and records of the types of weather that occurred under similar patterns in the past.
What do climate models take into account?
Climate models calculate many different properties of the climate, including atmospheric temperature, pressure, wind, and humidity. The models calculate these properties for thousands and thousands of different points on a three-dimensional grid.
Are climate models mathematical?
Climate models are systems of differential equations based on the basic laws of physics, fluid motion, and chemistry. To “run” a model, scientists divide the planet into a 3-dimensional grid, apply the basic equations, and evaluate the results.
Why do we need climate models?
Climate models are important tools for improving our understanding and predictability of climate behavior on seasonal, annual, decadal, and centennial time scales. Models investigate the degree to which observed climate changes may be due to natural variability, human activity, or a combination of both.
Can we trust climate models?
Models can successfully reproduce important, large-scale features of the present and recent climate, including temperature and rainfall patterns. … “Not doing anything about the projected climate change runs the risk that we will experience a catastrophic climate change.
What are coupled climate models?
A coupled climate model is a computer code that estimates the solution to differential equations of fluid motion and thermodynamics to obtain time and space dependent values for temperature, winds and currents, moisture and/or salinity and pressure in the atmosphere and ocean.
What are the limitations of climate change models?
an incomplete understanding of the climate system, an imperfect ability to transform our knowledge into accurate mathematical equations, the limited power of computers, the models’ inability to reproduce important atmospheric phenomena, and.
Who develops climate models?
MIT’s Climate Modeling Initiative is a collaboration between scientists at MIT, coordinated by the Center for Global Change Science, to develop a modeling infrastructure for the study of the atmosphere, ocean and climate of the Earth.
What can be said about using computer models in climate change research?
What can be said about using computer models in climate change research? Computer models can be used to forecast future climate change. … Global warming refers to an increase in Earth’s average temperature, while climate change encompasses a wide variety of changes in Earth’s climate.
How many climate models are there?
One simple answer to the question of why there are so many climate models is that science is a global activity. Around the world, there are roughly thirty research groups that have developed their own global circulation models.
How do weather models work?
In a model, the atmosphere is divided into a three-dimensional grid and each grid point is given the assimilated data. … Then at each grid point, the mathematical equations are applied and stepped forward in time. The outputs over many time steps specify future weather at all grid points.
How do climate models predict the future?
The Short Answer:
To predict future climate, scientists use computer programs called climate models to understand how our planet is changing. Climate models work like a laboratory in a computer. They allow scientists to study how different factors interact to influence a region’s climate.
What is the purpose of a global climate model?
A global climate model or general circulation model aims to describe climate behavior by integrating a variety of fluid-dynamical, chemical, or even biological equations that are either derived directly from physical laws (e.g. Newton’s law) or constructed by more empirical means. | https://savethebeaches.net/ecologic/quick-answer-are-climate-models-open-source.html |
The Princess Victoria, Princess Royal (Victoria Adelaide Mary Louisa; 21 November 1840 - 5 August 1901) was the eldest child of Queen Victoria of the United Kingdom and Prince Albert. She was created Princess Royal of the United Kingdom in 1841. She became German Empress and Queen of Prussia by marriage to German Emperor Frederick III. After her husband's death, she became widely known as Empress Frederick (or, in German: "Kaiserin Friedrich").
Birthday: November 21, 1840
Queen of Hearts Life Path: 45/9 Attitude: 32/5
Enter your birth day and find out who you are.
Wow am in love with this name, I will name my first daughter Shirley.
Love it
Dat is true
Mine is Dec. 18. Also King of Hearts...
my son name is tyron and he is exactly the way this explains
that's a luck for my second baby
Hi
Am glad
My venus is good or bad
I agree!! Very accurate! | http://m.sevenreflections.com/celebrities/victoria-princess-royal/ |
The invention discloses a movable intensive storage device. The movable intensive storage device comprises a skid-mounted outer box, a plurality of material boxes, an ex-warehouse table, a track assembly, a box taking robot and a sorting robot, wherein a storage area is arranged in the skid-mounted outer box, and an ex-warehouse end is defined; the material boxes are located in the storage area, and each material box is used for containing commodities; the ex-warehouse table is located at the ex-warehouse end of the skid-mounted outer box; the track assembly is arranged in the skid-mounted outer box and is positioned above the material boxes; the box taking robot is arranged in the box taking robot in a sliding mode and is located above the material boxes, and the box taking robot is usedfor carrying the material boxes where the order commodities are located from the storage area to the ex-warehouse table; and the sorting robot is located in the skid-mounted outer box and is arrangedadjacent to the ex-warehouse table, and the sorting robot is used for sorting the order commodities from the material boxes located on the ex-warehouse table. | |
Who is the best painter in India 2020?
Anish Kapoor tops list of ”Most Successful Indian Artists Alive Today 2020”
Who is famous painter in India?
When we talk about the famous painters of India, Raja Ravi Varma leads the list. Also termed as the “Father of Indian Modern Art”, Varma was the very first artist from this great nation who earned notable stature and appreciation at a global level.
Who is the No 1 artist in India?
Arijit Singh takes the top spot, BTS at #4. Arijit Singh, Tanishk Bagchi and Neha Kakkar continue to dominate the most streamed artists space this year. Arijit Singh’s ‘Shayad’ is the most streamed song followed by Trevor Daniel’s ‘Falling’.
Who is the most famous Indian painter?
Raja Ravi Varma is considered one of the greatest painters in the history of Indian art; and he is the most famous Indian artist.
Who is the richest painter in India?
S H Raza (born 22 February 1922) is a famous Indian artist who has lived and worked in France since 1950, but maintains strong ties with India. His works are mainly abstracts in oil or acrylic, with a very rich use of color.
Who is the No 1 painter in the world?
1. Leonardo Da Vinci (1452–1519) Renaissance painter, scientist, inventor, and more. Da Vinci is one of most famous painters in the world for his iconic Mona Lisa and Last Supper. 2.
Who is the best painter?
The 5 most renowned artist of all time.
- Leonardo da Vinci (1452–1519) Regarded as one of the greatest artists of all time, he is well known for his two remarkable paintings: The Mona Lisa and The Last Supper.
- Michelangelo (1475–1564) …
- Rembrandt (1606–1669) …
- Vincent Van Gogh (1853–1890) …
- Pablo Picasso (1881-1973)
19.07.2019
Who is blue painter of India?
Artist Sharad Bhardwaj, whose native place is Udaipur, Rajasthan and done his graduation from Jaipur and post-graduation from Bangalore. He is known as Blue Painter of India. He likes to create an Indian Contemporary Art and Modern Art.
Who is painter in India?
Some other prominent Indian painters born in the 19th century are Mahadev Vishwanath Dhurandhar (1867–1944), A X Trindade (1870–1935), M F Pithawalla (1872–1937), Sawlaram Lakshman Haldankar (1882–1968) and Hemen Majumdar (1894–1948).
Who is the best singer in India 2020?
Top 10 Best Indian Singers 2020
- Ankit Tiwari.
- Neha Kakkar. …
- Sunidhi Chauhan. …
- Armaan Malik. …
- Sonu Nigam. …
- Shaan. …
- Atif Aslam. …
- Yo Yo Honey Singh. When it comes to the best Bollywood singers, it is impossible to exclude Yo Yo Honey Singh. …
24.03.2020
Who is the biggest artist in India?
This is a list of notable artists who were born in India and or have a strong association with India.
- Rabindranath Tagore (1861–1941)
- Raja Ravi Varma (1848–1906)
- S. G. Thakur Singh (1899–1976)
- Silpi (1919–1983)
- Benode Behari Mukherjee (1904–1980)
- Gaganendranath Tagore (1867–1938)
- Sunil Das (1939–2015)
Who is #1 artist on Spotify?
Most followers
|Rank||Artist||Followers (millions)|
|1||Ed Sheeran||79.94|
|2||Ariana Grande||62.67|
|3||Drake||54.67|
|4||Justin Bieber||45.56|
Who is known as father of painting?
Pablo Picasso is the father of painting in the world.
Who first painted Hindu gods?
A prolific artist, Raja Ravi Varma is believed to have made around 7,000 paintings before his death at the age of 58. April 29 is the birth anniversary of the famed Indian painter Raja Ravi Varma (1848-1906), remembered for giving Indians their western, classical representations of Hindu gods and goddesses.
Who was the first man in India to paint in modern art?
1. At the age of 7, Raja Ravi Varma unveiled his painting skills on the walls of the Kilimanoor palace with the help of charcoal. 2. | https://lizsscribbles.com/other-drawing-soft/who-is-best-painter-in-india.html |
Q:
Defining Topological Continuity
I have seen this definition many times:
Topological Continuity: A function $f:X\rightarrow Y$ is continuous if for all open sets $U \subseteq Y$, the preimage $f^{-1}(U)$ is open in $X$.
I don't understand why the notion of openness is important to topological continuity. Can someone explain this?
By the way, I understand the definition of analytic continuity just fine, just to clarify it's topological I'm struggling with.
A:
The basic idea is the a function $f:X\to Y$ is continuous iff for any open set $V$ containing $f(x)$, there is an open set $O\ni x$ such that $f(O)⊆V$. Thus, given any nbhd (i.e. a degree of closeness) $V$ of $f(x)$ we can take points $O$ "close enough" to $x$ so that all their images are "close enough" to $f(x)$. In metric language, this translates to $f(B(x,δ))⊆B(f(x),ε)$ -- this is the analytic definition you speak of.
Indeed, to say that given any $\varepsilon>0$ there is $\delta >0$ such that whenever $d(x,y)<\delta$ then $d'(f(x),f(y))<\varepsilon$ says precisely that the image of the ball $B(x,\delta)$ is contained in the ball $B(f(x),\varepsilon)$. Since every open set $O$ containing $f(x)$ in a metric space contains a ball $B(f(x),\varepsilon)$, this says that for any open set $O$, $f^{-1}(O)$ is open: take $x\in f^{-1}(O)$, i.e. $x$ such that $f(x)\in O$ and use the above to get $f^{-1}(O)$ contains a ball $B(x,\delta)$.
Conversely, given the open set $B(f(x),\varepsilon)$, saying $f^{-1}(B(f(x),\varepsilon))$ is open means in particular (since $x\in f^{-1}(f(x))$) that there is an open ball $B(x,\delta)$ wholly contained in $f^{-1}(B(f(x),\varepsilon))$. This is equivalent to $f(B(x,δ))⊆B(f(x),ε)$, of course.
The intuitive aid of "closeness", perhaps more appropriate to say metric spaces, might break down when we allow arbitrary topologies. Nevertheless, it is usually an appropriate tool to figure out what's going on.
| |
compute ID group-ID orientorder/atom keyword values ...
ID, group-ID are documented in compute command
orientorder/atom = style name of this compute command
one or more keyword/value pairs may be appended
keyword = cutoff or nnn or degrees or components cutoff value = distance cutoff nnn value = number of nearest neighbors degrees values = nlvalues, l1, l2,... components value = ldegree
Examples
compute 1 all orientorder/atom compute 1 all orientorder/atom degrees 5 4 6 8 10 12 nnn NULL cutoff 1.5 compute 1 all orientorder/atom degrees 4 6 components 6 nnn NULL cutoff 3.0
Description
Define a computation that calculates a set of bond-orientational order parameters Ql for each atom in a group. These order parameters were introduced by Steinhardt et al. as a way to characterize the local orientational order in atomic structures. For each atom, Ql is a real number defined as follows:
The first equation defines the spherical harmonic order parameters. These are complex number components of the 3D analog of the 2D order parameter qn, which is implemented as LAMMPS compute hexorder/atom. The summation is over the nnn nearest neighbors of the central atom. The angles theta and phi are the standard spherical polar angles defining the direction of the bond vector rij. The second equation defines Ql, which is a rotationally invariant scalar quantity obtained by summing over all the components of degree l.
The optional keyword cutoff defines the distance cutoff used when searching for neighbors. The default value, also the maximum allowable value, is the cutoff specified by the pair style.
The optional keyword nnn defines the number of nearest neighbors used to calculate Ql. The default value is 12. If the value is NULL, then all neighbors up to the specified distance cutoff are used.
The optional keyword degrees defines the list of order parameters to be computed. The first argument nlvalues is the number of order parameters. This is followed by that number of integers giving the degree of each order parameter. Because Q2 and all odd-degree order parameters are zero for atoms in cubic crystals (see Steinhardt), the default order parameters are Q4, Q6, Q8, Q10, and Q12. For the FCC crystal with nnn =12, Q4 = sqrt(7/3)/8 = 0.19094…. The numerical values of all order parameters up to Q12 for a range of commonly encountered high-symmetry structures are given in Table I of Mickel et al..
The optional keyword components will output the components of the normalized complex vector Ybar_lm of degree ldegree, which must be explicitly included in the keyword degrees. This option can be used in conjunction with compute coord_atom to calculate the ten Wolde’s criterion to identify crystal-like particles, as discussed in ten Wolde.
The value of Ql is set to zero for atoms not in the specified compute group, as well as for atoms that have less than nnn neighbors within the distance cutoff.
The neighbor list needed to compute this quantity is constructed each time the calculation is performed (i.e. each time a snapshot of atoms is dumped). Thus it can be inefficient to compute/dump this quantity too frequently.
Note
If you have a bonded system, then the settings of special_bonds command can remove pairwise interactions between atoms in the same bond, angle, or dihedral. This is the default setting for the special_bonds command, and means those pairwise interactions do not appear in the neighbor list. Because this fix uses the neighbor list, it also means those pairs will not be included in the order parameter. This difficulty can be circumvented by writing a dump file, and using the rerun command to compute the order parameter for snapshots in the dump file. The rerun script can use a special_bonds command that includes all pairs in the neighbor list.
Output info:
This compute calculates a per-atom array with nlvalues columns, giving the Ql values for each atom, which are real numbers on the range 0 <= Ql <= 1.
If the keyword components is set, then the real and imaginary parts of each component of (normalized) Ybar_lm will be added to the output array in the following order: Re(Ybar_-m) Im(Ybar_-m) Re(Ybar_-m+1) Im(Ybar_-m+1) … Re(Ybar_m) Im(Ybar_m). This way, the per-atom array will have a total of nlvalues+2*(2l+1) columns.
These values can be accessed by any command that uses per-atom values from a compute as input. See the Howto output doc page for an overview of LAMMPS output options.
Restrictions
none
Default
The option defaults are cutoff = pair style cutoff, nnn = 12, degrees = 5 4 6 8 10 12 i.e. Q4, Q6, Q8, Q10, and Q12.
(Steinhardt) P. Steinhardt, D. Nelson, and M. Ronchetti, Phys. Rev. B 28, 784 (1983).
(Mickel) W. Mickel, S. C. Kapfer, G. E. Schroeder-Turkand, K. Mecke, J. Chem. Phys. 138, 044501 (2013).
(tenWolde) P. R. ten Wolde, M. J. Ruiz-Montero, D. Frenkel, J. Chem. Phys. 104, 9932 (1996). | https://lammps.sandia.gov/doc/compute_orientorder_atom.html |
So you’ve got yourself a spiffy rocketship and you’re heading out into space. What do you load it up with?
Which things you put on your ship will depend on where you’re going and what you intend to do. There are three basic cases:
1. Short trip: You’re on local patrol and will return shortly to base, whether that be a planet, moon, space station, or carrier ship.
2. Civilization: You’re going somewhere relatively well-established, in which case you’ll be able to pick up supplies along the way.
3. Self-sufficiency: You’re headed off to the frontier where you’ll need to bring all your own supplies for a long duration.
In general, an item that is useful for case (1) is also useful for (2) and (3). Similarly, an item useful for case (2) is likely useful in case (3). However, the reverse is not necessarily true. In this thread items will be listed with the lowest numbered case in which they are useful, and will be assumed useful in higher-numbered cases as well. This means, for instance, that type-1 items are useful for nearly every ship, and type-3 items are only really useful for ships going “off the grid” to rely solely on what’s aboard for extended periods.
For example, a fighter or defense ship only needs a few type-1 items. A cargo freighter plying the trade routes may spend days or weeks in space, and thus will have some type-2 items as well. A prospector ship looking for new mining or colonization opportunities will probably be gone for months, so it carries far more supplies including type-3 items.
Furthermore, items can be separated into various categories based on what functions they serve. Here are a number of items, split into 7 categories and sorted by use case. For the sake of completeness, this includes some things that are likely to be built into the spaceship. It also includes some sci-fi staples that may not be physically possible, or may not appear in any given sci-fi setting. It does not list third-party cargo being carried, as that could be anything.
Spoiler
Fundamentals: Essential components of a working spaceship.
-
Communication link
Flight controls
Generators
Long-range sensors
Maneuvering thrusters
Warp drive
-
Redundant backup systems
Life support: Necessary or useful for protecting the soft fleshy things aboard.
-
Heat sinks
Oxygen recycling system
Shields and armor
-
Airlocks
Escape pods
Radiative cooling
Water recycling system
-
Hydroponic farm
Medical devices
Convenience: Items one could live without, but wouldn’t want to.
-
Acceleration compensator
Climate control
-
Artificial gravity source
Bathrooms
Crew berths
Dishes
Entertainment items
Exercise equipment
Extra clothing
Furniture
Interior doors
Kitchen facilities
Personal items
Trash compactor
Utility: For getting things done.
-
Cloaking device
Computers
Data storage
Weapons
-
Repair tools
Small arms
Spacesuits
-
External manipulator arms
Fuel synthesizer or scoop
Mining tools
Scientific instruments
Planetary: For various interactions with planets and moons.
-
Atmospheric flight wings
-
Landing shuttle
Teleportation device
-
Aerial vessels
Nautical vessels
Terrestrial vehicles
Cargo capacity: For transporting various materials safely.
-
Chemical tanks
Cryogenic freezer
Hermetically sealed chamber
Passenger berths
Refrigerated cargo space
Consumable: Things that get used up over time.
-
Air
Ammunition
Fuel
Water
-
Food and drink
Goods for trade
Medicine
Recreational drugs
Spare parts
Special purpose chemicals
Toiletries
-
Building materials
What else would you put on a spaceship, and in what circumstances? | http://asw.forums.cytheraguides.com/topic/22077/what-do-you-bring-on-your-spaceship- |
Thermal conduction is the flow of thermal energy (heat) from higher to lower temperatures through molecular vibrations and collisions. Conduction occurs within an object or from a hot object to a cold object in contact with the former. It can occur in solids, liquids, and gases but is primarily observed in solids where molecules are closely packed. Heat will continue to flow until thermal equilibrium is reached.
Examples
- Warming hands by touching a hot body
- Heating one end of a metal rod
- Heating a frying pan on top of a stove
- Hot air immediately above the Earth’s surface
How is Heat Transferred Through Thermal Conduction
According to kinetic theory, matter is made of particles that are in constant random motion. This motion manifests as thermal energy, which depends on the temperature. The higher the temperature, the higher the thermal energy. The motion of particles, whether translatory or vibrational, leads to collisions. The particles transfer energy among themselves. Consequently, heat travels from a high-temperature region to a low-temperature region.
Equation
Fourier’s Law of Thermal Conduction
For thermal conduction to occur, there has to be a temperature gradient. Fourier’s law of thermal conduction states that the time rate of heat transfer through a material is proportional to the negative temperature gradient and the area through which the heat flows at right angles to that gradient. Mathematically, Fourier’s law can be written as
Q = K A ΔT/Δx
Where
Q: Heat transfer rate (Js-1 or W)
K: Thermal conductivity (Wm-1K-1)
A: Cross-sectional area (m2)
ΔT/Δx: Temperature gradient (Km-1)
Suppose heat flows through a conductor of thickness d whose ends are at temperatures TA (hot) and TB (cold). The heat flowing per second through the conductor is
Q = K A (TA – TB) /d
Thermal Conductivity
Thermal conductivity is a physical property of substances. In the above equation, suppose A = 1, d = 1, and (TA – TB) = 1. Then
K = Q
Thus, thermal conductivity is defined as the amount of heat flowing through a conductor of unit length, whose cross-section has a unit area and whose ends are at a unit temperature difference.
Metals have high thermal conductivity because their valence electrons are delocalized and can efficiently conduct heat. For example, the thermal conductivities of silver and copper are 406 Wm-1K-1 and 385 Wm-1K-1, respectively.
Insulators are poor conductors of heat. They have voids in between the atoms, which interfere with heat transfer. For example, the thermal conductivity of wood ranges from 0.04 to 0.12 Wm-1K-1. Air is a poor conductor of heat. Its thermal conductivity at 0 ˚C is 0.024 Wm-1K-1. | https://www.sciencefacts.net/conduction.html |
Q: What are the opening hours of the library?
The Library is open on all days except the government declared holidays in the state of Kerala. Its working hours are:
- Normal working days: 8.00 am to 8.00 pm
- Second Saturday : 8.00 am to 2.00 pm
- Sunday : 8.30 am to 2.00 pm
Q: What are the telephone numbers for contacting the Library?
- Librarian : 0494 2407290
- Library Office : 0494 2407287
- Circulation Division : 0494 2407285
Contact information including e-mail addresses, is given here
Q: How do I join the Library?
- Terms and conditions are availble in the link Library Rules
Q: What should I do if I've lost my Library card/ Library Identity Card?
- Report it immediately to the circulation division.
- Duplicate Library card will be issued on payment of Rs. 20.00 and Rs. 25.00 for duplicate Library Identity Card subject to the verification report of the section concerned.
- In case of loss of Library Identity Card a stamp size photo is to be submitted.
Q: How do I check out books?
- Select the required book(s).
- Take it to the counter in the stack room along with the reader's ticket (one ticket for each book) and identity card.
- The book will be returned by stamping the respective due date with a token.
- Show the book at the property counter and hand over the token.
- Now you can leave the library with the book(s).
Q: How many items can I borrow?
- Teachers of the University Departments : 6
- All other members : 3
Q: How long can I borrow for?
- 30 days without fine.
Q: What should I do if the book I borrowed got lost?
- You can either replace the book (publication and purchase details can be obtained from acquisition division) or pay four times of the cost of book plus 20% of the cost price as processing charge.
Q: How do I renew an item?
- Come in person with id card or send a mail to the address [email protected] or use this link
Q: How do I reserve an item?
- Submit your request to the stack in the prescribed form (available from stack room).
Q: What digital resources are available to me?
- Please check the link
Q: May I photograph, scan, or photocopy library materials?
- Only with the permission of the divisions concerned.
Q: What are the overdue item fines and fees?
- Books issued from stack: 50 paise per volume per day.
- Text books issued from the reference section: Rs. 5.00 per volume (Issued after 7 pm and to be returned before 10 am the next day).
Q: How can a user recommend a book for purchase?
- Submit your recommendation to the acquisition section directly or
- Submit this form. | http://library.uoc.ac.in/?q=faq |
21 September 2014
REMINDER FOR SUNDAY, 21 SEPTEMBER:
10 a.m.: Today we will be holding Atom’s memorial WOD at CrossFit Kingstowne at 10 a.m. during open gym. I welcome anyone that would like to join us and take a moment to remember him and his life on this day. The workout is a team workout as he always loved a good team WOD. The workout is posted below.
3 p.m.: I will be we hosting the Annual CFL/CFK Ladies Clothing Exchange at my house beginning at 3 p.m. During the gathering, Alice M. will be hosting a Stella and Dot Party and Shannon Q. will host a Rodan and Fields Party. We welcome you to bring any gently used, but unwanted clothing for exchange. Anything not snagged will then be donated to charity. Even if you do not have anything to bring, we welcome you to come by, check out all the great products that Alice and Shannon are bringing, and get to know some of your fellow CFL/CFK ladies a bit better.
CrossFit Kingstowne:
Open Gym: 10 a.m. to 12 p.m.
Free Intro Class: 12 p.m. to 1 p.m.
CrossFit Liberation:
Open Gym: 10 a.m. to 11 a.m.
Free Intro Class: 11 a.m. to 12 p.m.
ATOM’S MEMORIAL WOD:
We will begin running heats for the WOD at 1000. Heats will run as necessary until we get through all the individuals that wish to participate. The WOD will be a team WOD, comprised of two individuals for advanced, three for Rx, and four for scaled. We will be assembling teams on Sunday, but if you have a team you would like to create, please do so in advance and let us know on Sunday, otherwise we will place you on a team. Below is Atom’s WOD.
“ATOM”
30 Tire Flips (Rx: 750/650; S1: 500/350; S2: 350/250)
90 Sledge Hammer Swings (A: 45; Rx: 20/16; S1: 16/12; S2: 12/8)
Rope Climbs (Rx: 21 Climbs)
Air Squats (300) (Rx: Goblet Squats (53/35); S1/S2: Air Squats)
Toes-To-Bar (102)
Overhead Lunges with Plate (60) (Rx: 45/35; S1: 35/25; S2: 25/15)
Man Makers (15) (Rx: 45/35; S1: 35/25; S2: 25/15)
Ring Push Ups (60) (S1/S2: Hand Release Push-Ups)
Double Unders (150) (S1/S2: 450 Singles)
Deadlifts (21): (Rx: 275/185; S1: 225/135: S2: 165/95)
Burpee Box Jumps (60): (24″/20″)
Squat Clean Thrusters (15) (Rx: 135/95; S1: 115/75: S2: 95/65)
Hand Stand Holds (Rx: 60 Seconds; S1/S2: 34 Seconds)
Then…
Ruck Run (800 m) (Rx: 75/55; S1: 55/35; S2: 45/25)
Ruck Squats (60)
Ruck Down and Ups (15)
Ruck Push Ups (60)
Ruck Run (800 m)
Cash Out (Optional): 34 calorie row
One member of the team must be doing work at all times with the exception of Ruck Runs, Air Squats, and Hand Stand Holds. Teams cannot move on to the next exercise/movement until all work has been completed in previous task. Some of these events will be completed outside of the box (Tire Flips, Hammer Swings, and Ruck Run and Movements) – so please dress accordingly…we will be doing this Rain or Shine. We will not be running the clock. As Atom would say, “I don’t care how long it takes you to finish, as long as you finish”. Further scaled options are available as needed. | https://crossfitkingstowne.com/2014/09/21/21-september-2014/ |
Liquib 2.6 includes a new feature called Mapping, which transforms the display based upon functions of complex variables. There's also a new Mosaic Tool, and two methods have been added to the Plop Effect. Numerous other fixes and improvements. Further details follow:
As with all Liquib actions, Mapping activity is captured with
Scripts. Mapping
can optionally be included with Automatic Effects. Use the Maps
tab of the Configuration
screen to control how often Mapping should be applied, and which Map
Functions are available for random selection.
Tile Size controls the relative size of each tile. Setting the
Tile Size to a fairly low value makes it easier for the Mosaic Tool
to approximate the source image elements. The Shape Regularity %
determines how close to the 'ideal' Shapes the tiles will appear.
For example, with Shape Regularity % set to 100% and a Hexagonal Tile
Shape, the tiles will actually look like six-sided hexagons. When set
to lower percentages, the Mosaic Tool will attempt to deform the
Tiles as needed to align with detected image edges. So generally,
low Tile Size and low Shape Regularity % values give the Mosaic
Tool the most flexibility with fitting tiles to match source image elements,
and will result in more accurate representations of the picture. | https://whizical.com/Liq26.htm |
I am a research associate at the Gravity Exploration Institute at Cardiff University. I am an experimental physicist who uses laser interferometry experiments to investigate unresolved fundamental physics questions.
I am involved in the gravitational wave detector LIGO (Laser Interferometer Gravitational-Wave Observatory) and a member of LIGO Scientific Collaboration, which made its first detection of gravitational waves on September 14, 2015. I contributed to designing and constructing ultra-low noise-enhanced readout electronics for the Advanced LIGO detectors.
A novel technique for detecting high-frequency gravitational waves based on graviton-photon conversion in a static magnetic field is particularly intriguing to me. Inspired by that, I led the effort to find the first upper limits of a stochastic gravitational-wave background at optical and x-ray frequencies.
Recently, as a member of Quantum-enhanced Interferometry for New Physics, my major focus has been to design and build an experiment to investigate quantum space-time signatures using two co-located power-recycling Michelson interferometers. Also, because of how they are set up, the two co-located power-recycling Michelson interferometers will be sensitive to high-frequency gravitational waves and scalar field dark matter.
My doctoral dissertation focus was on vacuum magnetic birefringence (VMB), which has attained the highest sensitivity towards a first measure of the VMB (PVLAS experiment). I continued to work on this project as part of a new initiative named VMB@CERN. The goal of this project is to measure the vacuum magnetic birefringence by using the intense field from a spare magnet at the Large Hadron Collider (LHC) facilities.
Teaching
- Teaching assistant, Statistical Mechanics course 2021-2022, Cardiff University.
- Teaching assistant, Experimental Gravitational I/II course 2019-2020 and 2020-2021, Cardiff University.
- Teaching assistant, Modern Quantum Optics course 2018-2019 and 2019-2020, Cardiff University.
- Tutor, Mechanics and Matter course 2018-2019, Cardiff University. | https://www.cardiff.ac.uk/people/view/1422978-ejlli-aldo |
Inside the small beige brick building, the motions and the heavenly aroma are similar to those in a thousand other longtime, well-oiled baking operations.
The dough is weighed, the loaves are racked into a heated proofer, the entire rack bakes at once. The bakers knock the golden loaves from the pans and stack them on more racks, where they cool before being sliced and bagged.
But this is not just a bakery. The bread is not a product for sale.
Since 1990 at St. Joseph Abbey, just outside Covington, the Benedictine monks have operated a program called Pennies for Bread and The Abbey. The head baker is Brother Joseph Webre, assisted by Brothers Bede Roselli and Roman Keller and novice Carlos Morales.
The monks are baking bread for the needy, for the poor and disenfranchised and homeless, for those who deserve fresh bread and its fine crumb of dignity and humanity.
For 15 years, the program has provided 1,000 loaves two days a week, every week of the year, delivered to the hungry through charitable organizations in New Orleans and on the north shore, such as Boys Hope, Ozanam Inn, Grace House, Feed My Sheep and the NO/AIDS Task Force. The nondenominational program is financed through individual and corporate contributions.
Last spring, Milton Hock, a volunteer who works in the bread-bagging operation, started a fund-raising campaign to replace the bakery's oven, said the Rev. Augustine Foley, who manages the program. About $15,000 was raised to buy a new oven, since parts for the old one no longer are made. The next project, but on a back burner, Foley said, would have been replacing the delivery truck, which at the time had about 180,000 miles on it. As it travels its routes, the truck is the biggest advertisement they have for the program, he added.
Then came August and Hurricane Katrina. The silver lining that trailed in the hurricane's terrible wake was the profound number of people who wanted to offer aid.
"Loya Family Foundation, a private foundation in Cleveland, wanted to do something to help feed people in New Orleans" as well as the abbey, Foley said. The foundation's administrators found the abbey through a classic friend-of-a-friend connection: A Loya family member is spiritual director of the seminary in Cleveland where the Rev. Don Dunson, a longtime friend of St. Joseph Abbot Justin Brown, is a professor of theology. Dunson has been visiting St. Joseph Abbey for 25 years.
"We told them about the fact that we still needed another $10,000 to finish off the oven," Foley said, "and we told them about the truck, and they paid for both.
"We never met them. It was 20 minutes of bureaucracy," he said. "We were very lucky. We didn't have to hit our more meager operational budget for those items."
The monks started baking bread again only two weeks after the storm, after repairs to the bakery's gas line, which was uprooted by one of the many falling trees on the abbey's 11,000 acres. Though other abbey buildings were damaged, the bakery survived Katrina intact.
As soon as the program was fired up again, bread was sent to shelters in Covington, especially the largest one, at Covington High School. It also was served at the abbey to the many religious and other groups temporarily housed on campus for several weeks immediately after the storm. Then Notre Dame seminarians and staff were there the whole fall semester, displaced from their Carrollton Avenue campus, and they, too, shared the results of the bakers' work.
"We were able to stay active through the grace of God," Roselli said.
Webre and his crew put the weighed dough through an antique-looking Acme Rol-Sheeter, which flattens and rolls the balls of dough into loaf shapes. The crew members deftly tuck under the ends of the rolls, nesting each into its own battered metal pan. The pans are put on a rolling rack and then into the proofer, which looks like a refrigerator, only heated to 125 degrees with 73 percent humidity.
After 45 minutes, the racks are pulled out and the dough has done its magic yeast trick, springing way above the edges of the pans. The entire rack is rolled into the new vertical oven, where a clamp grabs it at the top. The rack starts to rotate, and spins the entire baking time behind a shiny glass door.
The oven "can be programmed with 99 different settings," Webre points out. So far, the brother bakers have tinkered and tweaked it during test runs. They have not tried the steam feature yet.
But they are baking twice a week, 40 loaves at a time, 42 pounds of Big Chief Flour from New Orleans in each batch. All this work is done with great good humor, fellowship in the air.
"The bread at St. Joseph Abbey is an example of perfect synergy," says Roselli, drawing guffaws from his co-workers, because they know he is playing it up for a visitor. But what he says is true, nevertheless.
"This morning we'll bake 500 loaves," Webre says. "Ordinarily, at full capacity, we do 1,000 loaves twice a week, 2,000 a week." The number of loaves has dropped because the number of available outlets has declined.
The food bank in Covington is getting more loaves now than it did before the storm, but only four to six groups in New Orleans currently receive bread.
Foley says the baking mission might be up to full capacity by summer, but they still don't know what is happening with all their former clients. Some interest has been expressed by groups in Baton Rouge, he says, but delivery in different directions would pose logistical problems.
"Right now I'm hoping to bring it all back to New Orleans," Foley says. "But we don't know about all these places. Some were wiped out."
The new oven makes a beeping noise, and Keller puts on a pair of blackened heavy-duty baking mitts that cover his arms to the elbows. He pulls one rack from the oven just as Webre wheels the next one from the proofer and starts it spinning inside the oven.
Later, after the bread is cool enough to slice, a crew of volunteers from the area arrives to put each loaf through the slicing machine, which vibrates noisily. The volunteers raise their voices above the din, creating another hive of well-organized frenzy.
Webre, who has worked with the baking program since its inception, had made raisin bread for them the day before. It is delicious.
More information about the Pennies for Bread program is available by calling Rev. Foley at (985) 892-1800. . . . . . . .
Food editor Judy Walker can be reached at jwalker @timespicayune.com or (504) 826-3485.
Mixing: Using a bread mixer can take 15 to 20 minutes to mix thoroughly. Use low setting for the first 8 to 10 minutes, then second or third gear for the remainder of the time.
Water: The amount of water is a tentative recommendation per recipe. Always add the first cup, then add the rest of the water, between 1/4 to 1/3 cup at a time. To mix this additional water, first allow the ingredients to be more or less mixed, then begin to add the rest of the water. Sometimes the best results come from slowly pouring a small amount every now and then around the sides of the bowl until the dough peels away from the sides and forms a ball. Remember it is not necessary to add all the water. The important thing is that you watch and feel the dough take shape through time. If, after mixing, the dough is very firm and tearing apart easily in your hands when kneading, then it's too dry and some water should be added. If the dough is excessively sticking to your fingers and unable to fold over upon itself, then it's too wet, and some flour should be added.
Kneading: For those using a bread mixer, be aware the dough begins to knead itself after a period between 10 and 15 minutes. Thus, kneading may be unnecessary. If, however, you're mixing by hand, the kneading process can take 8 to 10 minutes. The basic technique is to repeatedly fold the dough upon itself, massage and/or punch, until it begins to feel smooth and is somewhat elastic.
Rising: Because the ingredients in each recipe are so distinct in texture and weight, the amount of time it will take for each one to rise will be different, anywhere from 45 minutes to almost 2 hours. The standard by which you can measure the dough's readiness is when it doubles in size, or even slightly greater. You can let the dough rise, fall and rise again two or three times, kneading briefly in between, before finally putting it in the oven. This seems to help the ultimate firmness of the dough. | http://blog.nola.com/recipes/2006/02/our_daily_bread.html |
PROBLEM TO BE SOLVED: To provide a technology for efficiently computing recovery possibility in a consolidated taxation system.
SOLUTION: This recovery possibility computing device computing recovery possibility of deferred tax charges in the consolidated taxation system is provided with an input processing part, which inputs current tax matter information including information about a carryover balance of deficit of a parent company and each company in its consolidated group and future tax matter information including information about a taxable income before solving a future subtraction temporary difference and a future subtraction temporary difference solving amount and stores theses information in a storage means, and a recovery possibility computing part computing a consolidated income based on the values of the taxable income before solving a future subtraction temporary difference and the future subtraction temporary difference solving amount, storing the computed consolidated income in a storage means, reading a corresponding recovery possibility computing case formula from the storage means for each of the values of the consolidated income, the taxable income before solving a future subtraction temporary difference, and the future subtraction temporary difference solving amount stored in the storage means, and computing recovery possibility according to the read formula with consideration given to all the factors related to recovery of the deferred tax charges.
COPYRIGHT: (C)2005,JPO&NCIPI | |
This pattern comes in two sizes, the larger of which calls for 1125 yards of a lace weight yarn and 660 size 8/0 beads. The smaller version is 470 yards of lace weight yarn and 330 size 8/0 beads. This shawl consists of three triangular panels of lace separated by arrow patterned "seams". The resulting shape is roughly three sides of a square. In the larger size each of those sides are aproximately 37", and the shawl is 16 inches long at center back. In the smaller size the sides are 26" and the center is about 12" long. | http://blackberry-ridge.com/aphrodite.htm |
CROSS-REFERENCE TO RELATED APPLICATIONS
BACKGROUND
SUMMARY
DETAILED DESCRIPTION
Examples
This application is a national phase application of International Application No PCT/GB2018/052553, filed Sep. 7, 2018, which claims priority to Great Britain Patent Application Serial No. 1714501.2, filed Sep. 8, 2017, all of which are incorporated herein by reference.
The present invention relates to systems and methods for analysing data sets to identify possible data relationships in the data sets that can be used, for example, to support creation and execution of queries on the data sets.
Relationships between different data collections, such as between different data tables in a relational database, are often defined by a database designer during creation of a database (e.g. as primary key to foreign key relationships) and are typically reflected in the design of queries and views that provide efficient access to specific data in the database. However, when data is exported from the original database to some other data repository (e.g. in order to bring together data from multiple disparate sources), structural information such as data relationships is often lost. This makes efficient querying of the data difficult. Furthermore, data originating from different sources may be interrelated without explicit relationships having been defined. Identifying relationships without access to original design data represents significant challenges, with past approaches to the problem often being computationally highly intensive.
Embodiments of the present invention accordingly seek to address deficiencies in prior approaches and/or provide alternatives to those approaches.
Accordingly, in a first aspect of the invention, there is provided a method of identifying relationships between given data collections of a plurality of data collections, each data collection comprising a plurality of data records, each data record comprising one or more data fields storing one or more data values, the method comprising performing a search process including: receiving a first seed value and a second seed value; identifying a first set of records from the plurality of data collections based on the first seed value; identifying a second set of records from the plurality of data collections based on the second seed value; searching for a common value across the first and second record sets, wherein the common value is a value which appears in a first field in a first record of the first record set and in a second field in a second record of the second record set, preferably wherein the first record is from a first data collection and the second record is from a second data collection; and in response to identifying the common value, outputting (and/or storing) an indication identifying a candidate relationship between the first field of the first data collection and the second field of the second data collection.
This approach allows seed values (e.g. known data) to be used to guide the search for relationships, reducing the processing burden compared to approaches based on exhaustive analysis of data sets. Data collections may e.g. correspond to data tables or other data structures storing data as records/rows made up of fields/attributes, or using other analogous structures.
Identifying the first record set preferably comprises identifying one or more records containing the first seed value. Identifying the second record set preferably comprises identifying one or more records containing the second seed value. The search for a common value is preferably performed using the identified records.
Preferably, the method comprises, in response to not identifying the common value when searching using the identified records, adding one or more records to either or both of the first and second record sets, and repeating the search for a common value using the added records. This allows the search to be expanded to related records (possibly in other data collections, e.g. tables), to allow relationships been data collections to be found even where the seed values do not directly allow related records to be identified. The search for a common value may be repeated using all records of the given record set including the added records and previously identified records or using only newly added records.
Adding records to a given record set preferably comprises: identifying one or more further values, preferably not including the respective first or second seed value, which appear in records of the given record set; and selecting one or more records to be added to the given record set based on the further value(s). The added records may be selected from any of the plurality of data collections and thus may be from the same or different data collections as the original records of the record set. Selecting one or more records to be added preferably comprises selecting one or more records from the plurality of data collections that include one of the further values.
Preferably, the identifying step identifies as the further values each distinct value appearing in the given record set other than the respective seed value. The selecting step may select every record from the data collections not already included in the record set that contains any of the identified further values.
The method may comprise performing the adding step for the first record set and repeating the searching step using the added records, and subsequently, if a common value is not identified, performing the adding step for the second record set and repeating the searching step using the records added to the first and second record sets.
The method may comprise, if no common value is identified, performing one or more further iterations of the steps of (a) adding records to one or more of the record sets and (b) repeating the searching step using the added records, until a common value is found or a termination criterion is met. The termination criterion may specify a maximum number of iterations.
Identifying one or more records based on a seed value or based on a further value preferably comprises performing a lookup of the seed value or further value in a value index, the value index mapping data values appearing in the plurality of data collections to locations where the data values appear, each location preferably comprising a reference to the data collection, record and field where a respective data value appears. The method may comprise generating the value index based on the data collections.
Preferably, the method comprises repeating the search process based on a plurality of training samples, each training sample comprising respective first and second seed values, to produce a plurality of indications of candidate data relationships, each indication indicating a potential relationship between a first field of a first data collection and a second field of a second data collection. The method preferably comprises analysing the plurality of indications to identify one or more probable data relationships. A “probable” data relationship may be a relationship having a high probability of representing a true relationship, based on some criterion indicative of the probability or strength of the relationship.
The method may comprise accumulating information about data relationships during the repeating of the search process and identifying one or more probable data relationships based on the accumulated information. Alternatively or additionally, the step of outputting the indications may comprise storing the indications, the method comprising processing the plurality of stored indications to identify one or more probable data relationships.
The method may comprise identifying a plurality of distinct candidate relationships, wherein a distinct candidate relationship is preferably a relationship between a given first field of a first data collection and a given second field of a second collection, and determining a measure indicative of a strength or likelihood of each distinct candidate relationship based on the analysis. The method may comprise determining the measure for a candidate relationship in dependence on a number of distinct occurrences of the relationship found during the search process. In doing so, multiple occurrences of the relationship with the same common value may be counted as a single distinct occurrence, or multiple occurrences with the same common value may be counted as multiple distinct occurrences.
The method may comprise, for each distinct candidate relationship identified between a first field of a first data collection and a second field of a second data collection based on one or more common values, determining one or both of: a first number, being a number of times the distinct candidate relationship was identified using the search process; and a second number, being a number of distinct values of the common values used to identify multiple instances of the candidate relationship; and determining the measure for the candidate relationship based on the first and/or second number.
The method may comprise determining the measure based on a ratio of the first number or the second number, and a total number of training samples processed.
Preferably, one or more of the distinct candidate relationships are selected as probable relationships based on the respective measures. Preferably, the method comprises outputting information specifying the selected probable relationships. The one or more relationships may be selected in dependence on a comparison of the measure computed for the candidate relationship and a threshold and/or by selecting a given number of relationships having a highest strength or likelihood according to the computed measures.
Optionally, the method may comprise using one or more identified candidate relationships or probable relationships in the creation of a query. The method may comprise receiving, by a query design tool, a selection of at least two data collections for a query, and adding a join to the query based on a candidate relationship identified by the search process and/or a candidate relationship selected as a probable relationship. The method may comprise outputting one or more relationships identified as probable relationships to a user, receiving a selection of one of the relationships, and adding a join to the query design based on the selected relationship. A relationship used for the query is preferably defined between a first field of a first data collection and a second field of a second data collection, the method comprising adding a join predicate to the query specifying an equivalence or other relationship between the first field and the second field.
In one embodiment, the data collections are associated with a data processing system comprising a data input interface, and the method comprises: inputting sample data to the data processing system via the data input interface, whereby the data processing system stores the sample data into a source database, and wherein the data collections form part of the source database or are copied from corresponding data collections of the source database; and running the search process to identify data relationships based on the sample data. Values from the sample data are preferably used as the seed values for the search process.
The method may comprise importing the data collections from one or more source databases into a data repository, with the method operating on the imported data collections.
The data collections may be, or include, data tables, optionally in or imported from one or more relational databases, wherein the records correspond to rows of the tables, and wherein the fields correspond to columns of the tables. Alternatively or additionally, the data collections may be, or include, object collections, typically corresponding to object classes, optionally in or imported from one or more object-oriented databases, wherein the records correspond to objects of the object collections, and wherein the fields correspond to data attributes of the objects. The data collections may include data structured in accordance with any data structuring paradigm, and furthermore may combine differently structured data collections; for example the plurality of data collections may include both relational database tables and object collections.
The method may comprise processing multiple training samples in parallel by parallel instances of the search process. The search process may be implemented as a paralleliszed map-reduce algorithm.
In a further aspect of the invention, there is provided a method of identifying aspects of a data schema of a database, the database associated with a data processing system having a data input interface, the data processing system adapted to store data input via the data input interface in the database, the method comprising: inputting sample data to the data processing system using the data input interface, whereby the data processing system stores the sample data in the database in accordance with the data schema; and analysing data from the database based on the sample data to identify one or more relationships between data collections of the database. Analysing data may comprise importing one or more data collections from the database into a data repository and analysing the imported data. Preferably, analysing data comprises using values from the sample data as seed values for a relationship search, the relationship search preferably comprising performing a method as set out in the first aspect of the invention or as described elsewhere herein.
In this way, known data ingested into a system that uses an unknown data schema can be used to probe that data schema. Preferably, the method is performed by a system separate from the data processing system, and with no access to or control over the way in which the data processing system handles and stores the sample data.
The invention also provides a system or apparatus having means, preferably in the form of a processor with associated memory, for performing any method as set out herein, and a tangible/non-transitory computer-readable medium comprising software code adapted, when executed on a data processing apparatus, to perform any method as set out herein.
Any feature in one aspect of the invention may be applied to other aspects of the invention, in any appropriate combination. In particular, method aspects may be applied to apparatus and computer program aspects, and vice versa.
Furthermore, features implemented in hardware may generally be implemented in software, and vice versa. Any reference to software and hardware features herein should be construed accordingly.
Embodiments of the invention provide systems and methods for discovering relationships between data collections. In preferred embodiments, the data collections are in the form of data tables that have been imported from one or more sources into a single data repository. The system provides a relationship discovery module that searches for relationships between the tables. Such relationships may include relationships that were defined explicitly in the original database schemas of the databases where the tables originated, but that have been lost during importing of data. Relationships may also include relationships that are inherent in the data but were never explicitly defined, for example in the case of tables originating from different source databases.
FIG. 1
A data processing system in which embodiments of the invention may be used is shown in overview in .
It should be noted that, in the following description, specific implementation details are set out by way of example (for example in relation to database and software technologies used and details of the software architecture of the system—e.g. the use of Hadoop/Hive technologies). These relate to an exemplary implementation of the system but should not be construed as limiting, and alternative approaches and technologies may be substituted.
FIG. 1
110
As depicted in , the data processing system comprises a central data repository , which may also be referred to herein as a “data lake”, and may comprise any data storage technology. Preferably, the data lake allows data to be stored in an unstructured or flexibly structured manner. For example, the repository or data lake may not require a fixed or pre-defined data schema. The data lake may be (or may include) a NoSQL or other non-relational database, such as a document-oriented database storing data as “document” data objects (e.g. JSON documents), a key-value store, a column-oriented database, a file system storing flat files, or any other suitable data store or combination of any of the above. However, in other embodiments, the data lake could alternatively include a conventional structured database such as a relational database or object database.
102
In the examples described herein, the data lake is implemented as a Hadoop data repository employing a Hadoop Distributed File System (HDFS) with an Apache Hive data warehousing infrastructure. Hive Query Language (HQL) is used to create and manipulate data sets in the HDFS to store data extracted from the data sources .
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The data processing system provides a software component referred to as the “Data Tap” tool for importing data from any number of data sources -, -, - into the data repository .
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The data sources -, -, - are typically structured databases (e.g. relational or object databases) but any form of data source may be used, such as flat files, real-time data feeds, and the like. In the following examples, the data sources are relational databases managed by conventional relational database management systems (RDBMS), e.g. Oracle/MySQL/Microsoft SQL Server or the like.
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A given source database consists of a number of tables (where a table comprises a set of rows or records, each divided into one or more fields or columns). The Data Tap tool may import a database in its entirety (i.e. including all tables) or alternatively may import only one or more selected tables. Furthermore, the system may import tables and data from a single data source or from multiple data sources into the same data repository . Thus, data that originated from differently structured data sources having different original data schemas may coexist within data repository in the form of a collection of Hive tables . Other data (e.g. imported from other sources) may also exist in the repository as flat files, in the form of HDFS files .
In one example, imported table data may be stored in files in the HDFS (e.g. in Hadoop SEQUENCEFILE format). In practice, except possibly for very small tables, a given source table may be partitioned across multiple files in the HDFS. The files are partitioned by row, each containing the full set of columns imported from the source table (while typically all columns of the source table will be imported this need not always be the case). Additional columns of management data may be added to the imported tables for management purposes during import, for example to record import timestamps and the like. The files are placed in a directory structure, such that the files associated with a single source table preferably reside in a common directory (e.g. with separate directories for each source table, though alternatively files could be spread across multiple directories e.g. depending on whether the tables are partitioned at source).
Apache Hive enables a database structure to be applied to these files, such as tables and columns, and the structure information is stored in the Hive database known as the Hive Metastore. Thus, the term “Hive tables” is used to describe the table structures that are applied across the many files in a HDFS file system. A Hive table is thus a collection of structured HDFS files with each file corresponding to a partition of the source table comprising a subset of the rows of that table. Hive commands (using HQL) are available to access this data and also to update the table structure. HQL provides a similar syntax to SQL.
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The data in data repository may be made available to external processes or applications, e.g. analytics application and query builder application . Thus, the described approach can enable an organization to bring together information from many disparate databases (possibly supporting different operations of the organization), and analyse and process the data centrally.
When importing data from many different data sources, knowledge of the contents of the data tables and their interrelationships may be lost.
Furthermore, it may often be the case that data imported from disparate data sources is interrelated even though (being from disparate sources) there was no relationship designed into the source databases. For example, a gas or similar utilities provider may import a database of gas supply accounts from a supply part of the organization and a database of boiler maintenance data from a service/maintenance part of the organization. The data may be related in that some supply customers may also be maintenance customers. Thus, there may be relationships between data in the multiple data sources, which may, for example, manifest in overlapping data items appearing in both sets such as customer identifiers or names, addresses, meter or boiler serial numbers and the like. The above is merely one example, and similar relationships may occur between disparate data sources maintained by organization within any field (e.g. medical, banking, manufacturing etc.)
It is not necessarily the case, however, that equivalent or related data from different data sources will reside in tables/columns having the same or related names, and documentation for the source databases may be incomplete or inconsistent, making it difficult to work with the data after import.
Furthermore, even where multiple tables are imported from the same data source, relationships between tables (which may e.g. be defined in the form of metadata, queries, views or the like in the source database) may be lost during the import process. Such relationships typically relate data from one table with data from another. For example, in a “customer” and “order” table, a unique customer identifier used as a primary key in the “customer” table may be used as a foreign key in the “order table” to identify the customer who placed a particular order. This is an example of a relationship that may have been designed into the source database, where it may have been employed e.g. as the basis for table joins in defining queries, views etc. However, knowledge of the relationship may be lost when copying the raw table data into the central data repository. This loss of structural information and knowledge about the data presents a technical problem that impairs subsequent handling and querying of the data.
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Embodiments of the present invention address such problems by providing a Relationship Discovery module which can automatically discover relationships between Hive tables stored in the data repository . It should be noted, however, that while in the present embodiment the relationship discovery is performed on a set of Hive tables, the same approach could be used with conventional database tables stored in a relational database, or with data structured in any other data representation (e.g. objects in an object database). Thus, the described techniques could be applied to the source databases directly without importing data into repository .
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The Relationship Discovery module uses examples of known or suspected relationships between specific data values (“seed values”) as training samples to search for possible relationships in the data. Discovered relationships may represent e.g. primary-foreign key relationships or any other relationships that may allow a table join operation to be performed to combine data from different source tables. The identified relationships may then be used in the creation of join queries to combine and extract data from the data repository.
Commonly, the relationships identified are of the nature of a primary key to foreign key relationship, i.e. a relationship between a primary key in one table and a corresponding foreign key in another table. Such relationships are commonly used to represent one-to-one and one-to-many entity relationships in relational data schemas (with many-to-many relationships usually modelled using auxiliary mapping tables).
FIG. 2
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The Relationship Discovery module is illustrated in overview in , and comprises the following modules: Indexer , Table Walker , Distiller and Analyser . The operation of the Relationship Discovery module is summarised in outline below.
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In a first stage, a set of input tables are indexed by the Indexer (these may e.g. be Hive tables in the data repository ). This involves creation of an index which maps values appearing in table fields to the table, row and field locations of those table fields.
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In a second stage, Table Walker module processes the indexed tables, based on training data , to identify common values across tables that might indicate table relationships.
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In a third stage, the Distiller compiles sets of values and table-column pairs that may represent relationships between database tables.
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In the fourth stage, the Analyser analyses the output of the distiller to identify a set of probable relationships . Here, “probable” relationships means those candidate relationships that appear strongly represented in the source data and/or have a high likelihood of representing true relationships in the data.
Indexer
FIG. 3
The operation of the Indexer is illustrated further in .
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The process starts in step with the selection of a first one of the input tables for processing. In step , the first row of the table is selected. In step , each value appearing in a field (column) of the selected row is added to the value index. In step , the process determines whether any rows remain to be processed in the table. If the end of the table has not been reached, then the next row is processed as before starting at step . Otherwise, processing of the table is complete and the process determines whether any further tables remain to be indexed in step . If yes, the process continues at step with the next table being selected for processing. Otherwise, the process finishes at step and the index is complete.
After all tables have been processed, the index consists of a set of entries each mapping a distinct field value appearing somewhere in the input records to the table location(s) where the value was found. For example, the index may take the following (abstracted) form:
Value
Location(s)
V1
(T1, R4, F2), (T1, R8, F2), (T2, R3, F4)
V2
(T2, R1, F5)
V3
(T1, R5, F3), (T2, R8, F4)
. . .
. . .
Here the “Value” column of the index lists the values found in fields of the input tables (represented by the example values “V1”, “V2”, “V3”), and the “Location(s)” column lists the location or locations where each value was found. Each location is shown as a tuple consisting of a table identifier, row identifier and field identifier; for example, “V2” was found in a single location, which is table “T2”, in row “R1” and field/column “F5”. Values “V1” and “V3” were each found in multiple locations. In practice, the locations may of course be represented using actual table names, field names, and row identifiers as used by the database or in any other appropriate way. The index is preferably ordered (e.g. alphabetically/numerically) and may be represented using a B-tree or other known indexing structure for access efficiency.
Relationship Discovery
FIG. 4
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provides a broad overview of the operation of the Table Walker process . The Table Walker process uses the value index generated by the Indexer as input, along with training data .
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The training data includes training samples on the basis of which a search of the database tables is performed. Each training sample comprises at least two seed values that might be expected to appear in the tables, typically based on some prior knowledge or suspicion that the seed values are in some way related to each other.
FIG. 4
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illustrates the processing performed for a single training sample, assuming the training sample comprises two seed values. In step , the process identifies a first set of table rows based on the first seed value of the training sample. The set of identified rows initially comprises those rows, taken from any of the input tables, which include the first seed value (in any of the fields of the row). The rows are identified by looking up the seed value in the value index created by the Indexer. The process retrieves the full contents (i.e. all the field values) of each identified row.
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In step the process identifies a second set of table rows based on the second seed value of the training sample, in the same manner as described for step , i.e. by looking up the second seed value in the value index to identify and retrieve rows in any of the input tables that include the second seed value.
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In step , the process searches for any common values across the identified sets of table rows. A common value is a value that appears in any field of a row of the first row set and also in any field of a row of the second row set.
Thus, in searching for common values, the process considers all values appearing in the identified rows (not just the seed values). However, in preferred embodiments, as the aim is to identify relationships between different tables, the search may consider only values that are common to rows from different tables—i.e. a common value is then a value that appears in a field of a row of a first table (from the first row set), and also in a field of a row of a second table (from the second row set) that is different from the first table. Other embodiments may remove this restriction (e.g. if relationships within a single table are to be identified).
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Assuming at least one common value is found (), then in step a candidate relationship between the tables and fields where the common value appears is identified in step (if there are multiple common values then multiple such relationships may be identified). If no common values are found across the row sets, then one of the row sets (or both) is (are) expanded in step . The expansion involves identifying additional rows based on other field values that appear in the already-identified rows (i.e. values other than the seed values). In essence, the other field values from the identified rows are used as additional seed values, and further table rows are retrieved using the value index. Those further rows are added to the row set being expanded. The expansion is described in more detail below.
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The process then continues at step , to search for common values using the expanded row set. The expansion in step may be repeated as long as no common values are found or the process may terminate when some termination criterion is met, for example after a set number of iterations.
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illustrates an example of the process in operation. In this simplified example, the seed values are value “V1” () and “V2” () and the tables being searched include “Table 1” () and “Table 2” (). In practice the search may involve any number of seed values and any number of tables, but a simpler example is used here for the sake of clarity.
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In this example, the process searches for appearances of “V1” using the value index and finds that value “V1” appears twice in Table 1: in rows and . The process also searches for appearances of “V2” using the value index and finds that value “V2” appears three times in Table 2: in rows , and .
524
510
512
526
514
516
518
520
512
518
522
522
Thus, the search produces two row sets: row set includes rows and for seed value “V1” and row set includes rows , , for value “V2”. The full contents of these rows are retrieved. The process then searches for any overlap in values from the first row set (containing values V1, x1, x2, x3, x4, C, and x5) in the second row set (containing values V2, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15, C and x16). The process here identifies a single common value, which is value “C” (), which appears in the second field of row and in the fourth field of row . This common value represents a candidate relationship between the relevant fields of Table 1 and Table 2 that could be indicative of a relationship existing between the tables (though alternatively it could be coincidental). The system records the candidate relationship (e.g. by adding it to a list of such candidate relationships), with the candidate relationship specifying the source table/column and destination table/column of the relationship and the common value used to identify the candidate relationship. For example, the system may maintain a candidate relationship table of the following form:
TABLE 1
Source
Source
Target
Target
Common
Table
column
table
column
value
T2
F3
T5
F1
X
T3
F1
T6
F2
Y
T1
F2
T2
F4
C
. . .
. . .
If no common values are found, then the row sets are expanded by looking for other rows that include values appearing in the already identified rows. For computational efficiency, the expansion may proceed in stages: first, the row set found for the first seed value is expanded. In the present case this involves using all other values appearing in the first row set as additional seed values (e.g. x1, x2, x3, x4, x5 and C, if it were now assumed that C was not in fact found as a common value in the other row set). All rows in any of the source tables where those values appear are identified using the value index, and the rows are added to the first row set. The search for common values between the (expanded) first row set and the second row set is then repeated. If a common value is found a candidate relationship is identified and the process ends.
526
If not, then the process continues by expanding the second row set . Again, this involves looking up the distinct values appearing in the second row set (e.g. x6, x7 etc.) in the value index and retrieving any rows from the input tables in which those values appear, adding them to the second row set.
If necessary, the expansion can continue in further iterations, expanding the first row set and second row set alternately, either until a common value is found or some termination criterion is met. For example, a maximum number of iterations may be defined with the search ending once the maximum number is reached.
FIG. 5B
FIG. 4
540
402
406
542
544
546
548
550
552
544
The iterative expansion is illustrated in . In step , the first and second row sets are identified and the initial search for common values is performed, as described above (e.g. with reference to steps - of ). If a common value is found (decision ), the process ends and a candidate relationship is identified at step . If no common value is found, then the first of the row sets is expanded in sub-process . This involves searching the value index in step using all distinct values appearing in the first row set (excluding the seed value since any rows with that value are already included). All rows identified from the value index are added to the first row set in step . The search for common values is then repeated in step , comparing the expanded first row set with the original second row set. Note that in this case only the added rows need to be considered since the other rows have already been compared to the second row set. If this search reveals a common value the process ends at step as before.
556
546
558
560
562
546
544
If no common value is found then the second of the row sets is expanded in sub-process , in the same manner as for sub-process . Thus, in step , all distinct values in the second row set (except seed value) are looked up in the value index and the identified rows are added to the second row set (). The search for common values is then repeated in step , this time comparing the expanded first row set to the expanded second row set. Again, only the newly added rows of the second row set need to be compared (the original rows of the set having already been compared in previous stages); however, these are compared to the full expanded first row set (i.e. to both the initial rows and the rows added when expanding the first row set in sub-process ). Again, if a common value is found the process ends at step as before.
546
If a common value has still not been found, the process may be repeated, by returning to sub-process to again expand the first row set, repeat the common value search, and if necessary expand the second row set. Subsequent expansions may be based only on values in the previously added set of rows (since other values will already have been processed). As a further efficiency, the process may ignore values in the previously added rows that were already considered in the rows of earlier iterations (e.g. by keeping track of all distinct values used in previous expansions and expanding only on newly identified distinct values). In each common value search, newly added rows from one row set are compared to the complete expanded row set of the other row set.
546
556
The expansion loop with sub-processes and may be repeated until a common value representing a potential candidate relationship is found or until some termination criterion is met, e.g. a maximum number of iterations (in an example embodiment, the maximum is set at three iterations). The process may also be terminated if the expansion identifies no additional rows or based on some other criterion.
524
526
While in the above examples, the process alternates between expanding the first row set and second row set , to reduce the searching involved at each stage, the process could alternatively expand both sets before repeating the search for common values. If at any stage multiple common values are identified, multiple candidate relationships may be recorded.
1. For first seed value V1, identify all table rows R1 where V1 appears
2. Do the same for second seed value V2 to identify rows R2 where V2 appears
3. Identify any overlapping values between the R1 row set and the R2 row set
4. If found, then candidate relationship exists between those fields containing the overlapping values
a. Identifying for each value of that row, all other rows where that value appears (resulting in a set of related rows R1′)
5. If none found then expand R1 by, for each row in R1:
6. Search for common values between R1′ and R2
a. Identify for each value of that row, all other rows where that value appears (resulting in a set of related rows R2′)
7. If no common value found, repeat expansion for second row set R2—i.e. for each row in R2:
8. Search for common values between R1+R1′ and R2′
9. If no common value found, repeat expansion and common value search for R1′ and R2′ in turn, until common value found or maximum number of iterations reached.
The following summarises the process, including expansion, in accordance with a specific embodiment:
The iterative expansion of row sets allows potential relationships to be identified even where the seed values do not appear in directly linked table rows. An illustrative example of this will be given below.
110
The Table Walker outputs the list of candidate relationships found during the search (e.g. this may be output as a text/comma-separated-value (CSV) file, or stored as a Hive table in repository ). The list indicates for each candidate relationship the table/column of the source table of the candidate relationship, the table/column of the target table of the candidate relationship, and the common value found at those locations (e.g. as shown in Table 1).
FIGS. 6A-6C
A concrete example of the operation of the algorithm using sample data is illustrated in .
In these examples it is assumed that the database includes customer and order information for an organization, including tables such as a “Customer” table listing customer details, and “Address” table listing customer addresses, an “Order” table listing product orders placed by customers, a “Bill” table listing billing data, and the like. In this example, it is further assumed that there is prior knowledge that a customer with name “Daljit” has in the past ordered a product identified by the keyword “Shoe”. This prior knowledge may e.g. have been obtained from an invoice, during a customer enquiry, from email correspondence, or in any other way. The relationship discovery process is thus carried out using the values “Daljit” and “Shoe” as seed values.
FIG. 6A
FIG. 6B
FIG. 6C
illustrates the value locations obtained from the value index for each value. shows the full rows corresponding to the identified locations. shows a (partial) listing of all the values appearing in the respective row sets for the different seed values. The algorithm compares the value sets and identifies that the value “CustKEY1” appears in location (T1, C1, R1) and also in (T3, C2, R7). This suggests a candidate relationship between table T1 column C1 and table T3 column C2.
In this example, the identified table relationship can be considered to be between “adjacent” tables since the seed values are linked by a single common field value from the source table to the destination table.
FIG. 7A
illustrates application of the algorithm to identify relationships in non-adjacent tables, i.e. where the seed values still reveal a relationship, but the relationship is not between the two tables in which the seed values appear. These relationships are identified using the iterative expansion technique described earlier.
FIG. 7A
shows contents of four tables, “Customer”, “Address”, “Order” and “Bill”. In this case, the seed values used for relationship discovery are “London” and “Shoe”. As described previously, the first step is the identification of the set of rows in which “London” appears (first two rows in the “Address” table). The second step is the identification of rows in which “Shoe” appears (seventh row in the “Order” table). However, those rows do not have any value in common. However, by expanding the row sets as described above (e.g. initially, the “London” rows may be expanded), rows in a third table are found (“Customer” table) that are linked to the “Address” table rows.
700
Specifically, in this case, expanding the two “Address” table rows in which initial seed value “London” appears will result in the algorithm looking for additional rows containing values such as “AddrKEY1”, “Gassy Cottage”, “Swamp Road”, “AddrKey2”, “Sparky Villa” etc. This will result in the algorithm finding the first two rows of the “Customer” table, which also contain values “AddrKEY1” and “AddrKEY2”. Those rows are therefore added to the first row set. Finally, the common value search reveals a common value (“CustKEY1”) which appears in one of those additional rows and also in the original row retrieved from “Order” table based on the “Shoe” seed value. This therefore implies a potential relationship between Column 1 of the “Customer” table and Column 2 of the “Order” table. For example, this could take the form of a unique customer identifier that appears as a primary key in the “Customer” table and as a foreign key in the “Order” table.
Thus the algorithm can be considered as searching for a path connecting a row containing the first seed value to a row containing the second seed value. By way of the row expansion, that path may extend across multiple tables, so as to reveal relationships other than between the immediate pair of tables containing the seed values.
In the above example, the Table Walker would thus add a candidate relationship of the following form to its output:
TABLE 2
Source
Source
Target
Target
Common
Table
column
table
column
value
Customer
Column 1
Order
Column 2
“CustKEY1”
Note that the terms “source” and “target” are used as labels and have no particular significance since the relationship is symmetric and thus the “source” and “target” could be swapped.
In one embodiment, this may be the only relationship added in response to identifying the common value. However, in an alternative embodiment, additional candidate relationships identified along the path between the seed values may also be added. In this case, the expansion of the rows from the “Address” table retrieved the first two rows of the “Customer” table based on values “AddrKEY1” and “AddrKEY2”. These may also indicate potential relationships between tables. Thus, in this embodiment, the following additional candidate relationships would be add
ed to the output:
TABLE 3
Source
Source
Target
Target
Common
Table
column
table
column
value
Customer
Column 1
Order
Column 2
“CustKEY1”
Address
Column 1
Customer
Column 5
“AddrKEYI”
Address
Column 1
Customer
Column 5
“AddrKEY2”
Such additional relationships may be recorded only if a common value is ultimately found. Alternatively, these candidate relationships found during the row expansions may be added to the output even if the search is aborted without a common value being found. As shown in Table 3, in the initial stage of processing, multiple instances of the same candidate relationship (same table/column pairing) are recorded separately in the output of the Table Walker.
While in the above examples, two seed values are used per training sample, this can in principle be extended to any number of seed values. In that case, row sets are generated for each training sample and the search for common values is performed across all row sets. As described above, each row set may be expanded in turn and the search repeated if the search reveals no common value.
Analysing Identified Relationships
The Table Walker process is repeated for each training sample of the training data, where each training sample corresponds to two (or more) seed values. For example, these processes may run in parallel, e.g. with parallel Table Walker instances operating on different training samples.
This produces a set of zero or more candidate relationships (source table/column, target table/column, common value) for each training sample.
The Distiller processes the Table Walker output to count up all repeated occurrences of the same candidate table relationship (where relationships are “the same”, i.e. not distinct, if defined between the same source/destination table/column pairings) and outputs a summarised list of relationships. For example, for the Table Walker output shown in Table 3, the following output could be generated:
TABLE 4
Source
Source
Target
Target
Occurrence
Table
column
table
column
count
Customer
Column 1
Order
Column 2
1
Address
Column 1
Customer
Column 5
2
Of course the output would typically be based on a large set of training samples and would contain many candidate relationships. The Distiller again generates the output as a text/CSV file (or could alternatively write its output to a Hive table in the repository or output it in some other way).
The Analyser aggregates and applies weightings to the candidate relationships and proposes the most likely relationships (i.e. those most likely to define actual table joins). The output of the Analyser may again be stored in the form of text/CSV files, and additionally may be provided as on-screen output, e.g. in the form of visualisations of joins/relationships.
218
In more detail, the Analyser module processes the output of the Distiller process to identify which of the identified potential relationships are likely to represent actual table relationships. In one embodiment, the analyser determines a measure of the probability that an identified candidate relationship corresponds to an actual table relationship based on the number of times that particular candidate relationship was observed compared to the total number of training samples processed. For example, the probability may be computed as the number of occurrences of the candidate relationship between a given column pair (e.g. T1C1-T2C2), divided by the number of training samples. Thus, a candidate relationship found for most or all training samples may indicate a high likelihood that the candidate relationship represents a genuine table relationship between the table/column pair, whilst a candidate relationship found for only one or a few training samples may indicate a low likelihood that the candidate relationship represents a genuine table relationship.
The output of the Analyser may e.g. take the following form:
Total training samples processed: 10
TABLE 5
Candidate
Relationship
relationship
Occurrences
Probability/Strength
T1C1-T2C2
3
3/10 = 30%
T1C5-T3C1
9
9/10 = 90%
T2C4-T4C2
1
1/10 = 10%
T3C1-T4C6
10
10/10 = 100%
Other approaches may of course be used to determine a value indicative of the probability, strength or quality of an identified relationship. For example, a weighting could be applied to increase the likelihood measure for high occurrence links and reduce the likelihood measure for low occurrence links. As another example, occurrences below a threshold (e.g. an absolute threshold such as one or two occurrences, or a relative threshold such as 5% of training samples) could be eliminated from the results altogether or have their relationship measure set to 0, to remove cases where candidate relationships may be due to coincidental matching values across table columns.
Instead of providing the separate Distiller process for counting the number of occurrences of each distinct table/column relationship in the Table Walker output, counts for distinct relationships could be accumulated by the Table Walker during the processing of training samples. However, separating these steps into separate processes allows more efficient parallelized implementation, e.g. in a map-reduce algorithm.
The Analyser then outputs the candidate relationships with their associated measures of strength/likelihood. In some embodiments, the Analyser may select only those relationships that meet particular criteria for output as a final set of “probable” relationships. For example, the Analyser may select relationships with a likelihood exceeding a predetermined threshold, or may select the best N (e.g. top 5) identified relationships according to the computed metric for output and further processing.
FIGS. 7B-7C
FIG. 7B
FIG. 7C
In an embodiment, the algorithm may be adapted to distinguish between the case where a given candidate relationship is found multiple times based on the same common value or based on multiple distinct common values. This is illustrated in . Here, shows an example where a particular distinct candidate relationship (between “Delivery postcode” in “Order Table” and “Postcode” in “Address Table”) is identified three times based on three distinct common values (“SW19 5BR”, “RG21 4PX”, “TN7 0GR”). shows an example where that same candidate relationship is identified three times but based on the same common value (“SW19 5BR” in each case).
FIG. 7C
FIG. 7C
In this embodiment, the distiller initially generates counts for each unique combination of candidate relationship and common value. The Analyser can then aggregate the counts for different values to generate a total count for each relationship. In doing so the Analyser may, for example, score multiple occurrences of the same candidate relationship with the same common value as a single relevant occurrence of the relationship (thus in the example the three occurrences would count only once) or may score each occurrence separately (in which case the example would count as three occurrences of that relationship). Which approach is used may be configurable.
More generally, the system may identify either or both the number of occurrences of the candidate relationship (e.g. the number of times it appears in the Table Walker output) and the number of distinct values in the common values used to identify multiple occurrences of the candidate relationship. Either or both value(s) may be used to determine the strength/probability of a given relationship (this may be configurable), e.g. as a ratio of one of the values to total number of training samples.
FIG. 7B
FIG. 7C
Different and/or more complex approaches could be used, e.g. aggregating relationship occurrences using weightings such that repeated occurrences of a relationship with distinct common values contribute more to the final score than repeated occurrences using the same common value. In this example, the system could weight the example (three matches based on three distinct values) more highly than the example (three matches based on one distinct value).
Applications
The identified relationships may be utilised in various ways, including in the design and execution of queries (described further below). A visualisation tool may also be provided for visualising the identified relationships (e.g. with the strength or likelihood indicated using the calculated likelihood measure). For example, such a tool could visualise an inferred schema including the tables and selected ones of the relationships (e.g. using the strongest identified relationships). A further example is the use of the relationship discovery for data schema diagnostics, is described in the next section.
Data Schema Diagnostics
FIG. 1
102
3
104
106
Referring back to , in this application of the relationship discovery algorithm, it is assumed that the algorithm is applied to an existing database - supporting an operational data processing system . As before the database is copied into the data repository by Data Tap module .
It is assumed that the data schema of the database is not known a priori—thus, it may initially be unknown how the data is structured into tables and table columns, or how tables are related to each other.
106
The basic table structures (i.e. tables, columns, data types) may be identified by the Data Tap module during import of the tables (e.g. by reading from the system tables in the source database, using a database API etc.) However, while this will reveal basic structure, it will not directly reveal the function or meaning of individual tables/columns. Furthermore, data relationships are generally not discoverable in this way.
102
3
104
In an embodiment, the system uses known sample data (essentially dummy data) as a “probe” to probe the schema of the database, by inserting the sample data into the source database - using the data processing system .
104
104
The sample data is inserted using the conventional data input methods provided by the data processing system . For example, system may include a set of data entry user interfaces through which operators (in normal use) enter new data records into the system. However, the data schema used to store such data is often much more complex than (and not directly derivable from) the structure of the user interfaces.
104
104
In the present embodiment, sample data is entered via the user interfaces of system , either manually, or preferably in an automated fashion, e.g. using scripts. Instead of inputting the sample data via user interfaces, the data processing system may provide automated data ingestion mechanisms (e.g. file import tools, APIs etc.) in which case the sample data can alternatively be inserted using those mechanisms in an automated fashion. The sample data can be any data with known values—possibly chosen as unusual/uncommon values to allow the data to be more easily distinguished in the imported tables—and could e.g. be (pseudo) randomly generated.
104
104
102
3
After the sample data has been input to data processing system , data processing system will store the data, using the unknown data schema, in database -.
106
102
3
110
120
Data Tap module is then run to import the tables from database - into the data repository . Subsequently, the Relationship Discovery tool is run to identify possible relationships in the data. In doing so, the Relationship Discovery tool uses data from the sample data as the training samples. This allows the system to identify how the entered data is reflected in relationships between data tables in the database.
104
For example, a name (“John Smith”) and address (“Main Street, Newtown”) of an individual may be entered as sample data into a single input screen of the data processing system . The database may store this data in multiple interrelated tables, for example a customer table with first name, surname and customer ID (primary key) fields and an address table with street, town, country fields etc., with the address table additionally using the customer ID as a foreign key to the customer table. This relationship would be unknown since the original data schema of the database is unknown. However, by running the previously described Relationship Discovery algorithm using selected values of the sample data as seed values, the relationship can be discovered. In this example, “Smith” and “Newtown” could be used as the two seed values forming a training sample. Of course, as previously described, the process may be repeated using multiple training samples based on the sample data, in order to obtain more information and greater confidence in the identified relationships.
A visualisation tool may be provided to visualise the possible relationships. Actual data contents may also be displayed to allow an operator to infer the likely functions of particular tables/rows. In one implementation, the tool may make this task easier by searching for occurrences of the specific sample data that was entered and displaying the specific tables/table rows containing that data, together with identified relationships and possibly indications of relationship strength based on the computed likelihood measures.
104
This information can then be used by the operator e.g. to define a schema for the data, create and run queries to extract useful data etc. The operator may also choose to insert additional sample data into the source database via system and rerun import/relationship discovery, for example to resolve specific questions or ambiguities concerning the data schema. In this way, the system may be used in an iterative fashion to probe the structure of the initially unknown data schema.
The described approaches can be particularly beneficial when attempting to utilise data managed by legacy systems, where details of data schema and relationships are manifested in the code, database queries etc. that form part of the implementation of the legacy system, but where those implementation details are not directly available.
A similar diagnostic approach can be used e.g. to identify inefficient structures in the database (e.g. unnecessary duplication of data, indirect data referencing etc.), to support database redesign, for example to enable more efficient data querying.
Query Builder
FIG. 1
114
Referring back to , embodiments may additionally provide a Query Builder application , which enables a user to construct queries using the discovered relationships.
FIGS. 8A and 8B
FIG. 8A
800
802
804
806
802
804
An example user interface of the Query Builder application is depicted in . illustrates an interface of the Query Builder displaying two tables and selected for the query by the user. These tables may have originated from different data sources and thus the relationships between the tables may not be known a priori. The interface also proposes a number of possible relationships between the tables which have previously been discovered by the Relationship Discovery module (illustrated as labelled lines connecting the respective column/field names of the respective tables). A visual indication of the relationship strength (based on the relationship likelihood or other metric computed by the Relationship Discovery module as described above) is provided by way of the colour and/or line weight used to represent the connections between tables—here a relationship between the CUSTID column of table and the CUSTID column of table is identified as the strongest relationship. The user may be able to view more detailed relationship information for each relationship (e.g. by clicking on or hovering over a relationship in the interface).
Instead of proposing previously discovered relationships, the Relationship Discovery module could be invoked on-demand by the Query Builder, in response to the user identifying the tables for the query.
810
FIG. 8B
The user then selects the required relationship e.g. by clicking on the link or label. At that point the Query Builder generates an initial query definition including a table join based on the specified relationship and a second screen () may then be displayed to allow the user to specify additional parameters of the query, such as which columns to include in the query output, the query criteria, and any grouping/aggregation/sorting to be performed.
110
After defining the query the query can then be executed to retrieve data from the data repository . In preferred embodiments, based on the user input a query statement or script is generated in accordance with an appropriate data query language, e.g. HQL or SQL. The generated query includes a table join based on the selected relationship, i.e. with a join defined on the table columns to which the relationship relates (this may be done e.g. by adding a WHERE statement or similar, such as “WHERE T1.A=T2.B” to define a join condition between table 1 column A and table 2 column B). The join type (e.g. inner/outer and left/right/full join etc.) may be specified by the user or a default join type may be used.
112
110
The query is then executed, e.g. in the case of the Hadoop system by submitting the generated HQL statement to Hive. Hive executes the query and returns the results to Query Builder or other relevant component (e.g. data analytics application ). The query results may also be transmitted to a user device (e.g. PC terminal or mobile device) for display to the user, stored as a new table in the data repository , or transmitted to a remote computer system for further processing.
In addition to direct execution the query can be saved in the system and if appropriate published to make it available for other users.
FIGS. 8A-8B
While illustrate a relatively simple query with two tables, more complex queries may be constructed including more than two source tables and/or multiple join relationships. Queries may also be combined by nesting (e.g. by using query output from one query as input to another query in place of a source table).
System Architecture
FIG. 9
800
902
906
illustrates an example of a hardware/software architecture of a server node which may be used to implement methods and techniques described herein. The server includes one or more processors together with volatile/random access memory for storing temporary data and software code being executed.
904
920
900
922
102
924
A network interface is provided for communication with other system components (e.g. other servers in a Hadoop cluster , where the server is operating as part of a cluster) and a wider network (e.g. Local and/or Wide Area Networks, including the Internet), for example, for connection to data sources , user terminals and other devices.
908
106
102
110
120
114
Persistent storage (e.g. in the form of hard disk storage, optical storage, solid state storage and the like) persistently stores software for performing the various functions, including one or more of: the Data Tap module for importing data from data sources into the data repository , Relationship Discovery module for identifying table relationships using the methods set out above, and Query Builder module to enable creation and execution of queries based on the identified relationships.
The persistent storage also includes other server software and data (not shown), such as a server operating system. The server will include other conventional hardware and software components as known to those skilled in the art, and the components are interconnected by a data bus (this may in practice consist of several distinct buses such as a memory bus and I/O bus).
924
924
A user may interact with the server from a user terminal (e.g. a PC terminal or mobile computing device). For example, user interfaces (UI) for the Data Tap, Relationship Discovery and/or Query Builder modules may be provided as web applications remotely accessible from user terminal .
FIG. 9
While a specific software and hardware architecture is shown in by way of example, any appropriate hardware/software architecture may be employed and any suitable hardware, database, API and UI technologies may be used.
106
120
114
Furthermore, functional components indicated as separate may be combined and vice versa. While in this example, a range of different processes , and are shown as implemented on the server, in practice these processes may be distributed across multiple servers, e.g. with different servers handling data import, table analysis and query design/execution functions. Furthermore, individual processes such as Data Tap and the Relationship Discovery algorithm may be implemented in parallelized form across multiple processing nodes. More generally, functionality may be distributed over any number of computing devices in any suitable manner.
In preferred embodiments, where appropriate, modules may operate in a parallelized fashion (e.g. using Hadoop map-reduce) across multiple physical or virtual servers or compute nodes in a Hadoop cluster.
110
FIG. 1
The data repository () may be implemented as persistent storage distributed over a number of servers in the Hadoop cluster (e.g. in the form of a Hadoop distributed file system). Those servers may provide data storage only or may combine data storage with any of the previously described processing functions.
120
FIG. 2
The Relationship Discovery module may be implemented using a map-reduce algorithm, for example, using the Hadoop Java map-reduce framework. Referring to , the Table Walker could be implemented as a set of parallel “map” tasks (e.g. operating on different training samples), with the distiller and analyser implemented as “reduce” tasks.
It will be understood that the present invention has been described above purely by way of example, and modification of detail can be made within the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred features of the present invention will now be described, purely by way of example, with reference to the accompanying drawings, in which:
FIG. 1
illustrates a data management system in which a relationship discovery module according to embodiments of the invention may be implemented;
FIG. 2
illustrates the operation and functional components of the relationship discovery module;
FIG. 3
illustrates an indexing process;
FIG. 4
illustrates the relationship discovery process in overview;
FIG. 5A
provides an illustration of a search process performed by the relationship discovery module;
FIG. 5B
illustrates iterative expansion of row sets during the relationship search;
FIGS. 6A-6C
show a worked example of the operation of the relationship discovery;
FIG. 7A
illustrates a relationship search involving more than two tables;
FIGS. 7B-7C
illustrate identification of multiple instances of the same candidate relationship;
FIGS. 8A-8B
illustrate an interface for a query builder tool that uses discovered relationships in the creation of data queries; and
FIG. 9
illustrates a hardware/software architecture of a server device on which various described processes or modules may be implemented. | |
What to make with gooseberries (or pichuberries)? The sweet and tart summer rhubarb bars.
Course
Dessert
Cuisine
American
Prep Time
45
minutes
Cook Time
30
minutes
Total Time
1
hour
15
minutes
Servings
12
servings
Calories
421
kcal
Ingredients
For the crust
2
sticks unsalted butter
softened
3/4
cup
light brown sugar
1/2
teaspoon
salt
1
teaspoon
vanilla extract
2
cups
whole wheat flour
1/2
cup
ground hazelnuts
For the topping
1/2
cup
whole wheat flour
3/4
cup
brown sugar
1/2
teaspoon
salt
3
ounces
unsalted butter
cold & cubed
1/2
cup
rolled oats
1/2
cup
shredded coconut
For the filling
1 8
oz
package of pichuberries
husks removed, and sliced in half
12
ounces
fresh rhubarb
cut into 1/2 inch pieces
1
teaspoon
vanilla extract
2
Tablespoon
sugar
1/4
cup
whole wheat flour
Instructions
Spray 9 x 13" pan with nonstick spray, line with parchment paper, and spray with nonstick again.
To make the crust, cream butter, sugar, and salt in a large bowl until light and fluffy. Add vanilla.
Turn mixer to low and add in flour and ground hazelnuts until combined.
Press dough into the prepared pan and chill till firm.
Bake at 325 degrees for 25 minutes rotating halfway through. Remove from oven and cool completely.
Using a food processor or a pastry blender, combine flour, brown sugar, and salt. Add in cubed butter and pulse until the mixture resembles coarse cornmeal.
Empty topping into bowl and mix in oats and coconut. Refrigerate until ready to use.
Once the crust is cool, make your filling.
Toss cut up rhubarb and pichuberries with vanilla and sugar. Add flour and toss until well coated.
Preheat oven to 350 degrees.
Place rhubarb pichuberry mixture on top of cooled shortbread.
Sprinkle 2 cups crisp topping evenly over the filling.
Bake at 350 degrees for 25-30 minutes. Allow to cool completely in pan. Refrigerate.
Nutrition Facts
Rhubarb Pichuberry Crumb Bars
Amount Per Serving (1 g)
Calories
421
Calories from Fat 207
% Daily Value*
Fat
23g
35%
Sodium
21mg
1%
Carbohydrates
47g
16%
Sugar 20g
22%
Protein
5g
10%
* Percent Daily Values are based on a 2000 calorie diet. | https://betsylife.com/wprm_print/recipe/21220 |
Kapton is a polyimide film developed by DuPont in the late 1960s that remains stable across a wide range of temperatures, from −269 to +400 °C (−452 – 752 °F / 4 – 673 K).[2] Kapton is used in, among other things, flexible printed circuits (flexible electronics) and thermal micrometeoroid garments (the outside layer of space suits).
The chemical name for Kapton K and HN is poly (4,4'-oxydiphenylene-pyromellitimide). It is produced from the condensation of pyromellitic dianhydride and 4,4'-oxydiphenylamine. Kapton synthesis is an example of the use of a dianhydride in step polymerization. The intermediate polymer, known as a "poly(amic acid)," is soluble because of strong hydrogen bonds to the polar solvents usually employed in the reaction. The ring closure is carried out at high temperatures (200–300 °C, 473–573 K).
The thermal conductivity of Kapton at temperatures from 0.5 to 5 kelvins is rather high for such low temperatures, κ = 4.638×10−3 T0.5678 W·m−1·K−1.[3] This, together with its good dielectric qualities and its availability as thin sheets have made it a favorite material in cryogenics, as it provides electrical insulation at low thermal gradients. Kapton is regularly used as an insulator in ultra-high vacuum environments due to its low outgassing rate.
Aircraft
Kapton-insulated electrical wiring has been widely used in civil and military aircraft because it is lighter than other insulators and has good insulating and temperature characteristics. For these reasons, the sunshield of the James Webb Space Telescope will be made of it.
Spacecraft
NASA's New Horizons spacecraft used Kapton in an innovative "Thermos bottle" insulation design to keep the craft operating between 10–30 °C (50–86 °F) throughout its more than nine-year, 3 billion mile journey to rendezvous with the dwarf planet Pluto on July 14, 2015. The main body is covered in lightweight, gold-colored, multilayered thermal insulation – like a survival camping blanket – which holds in heat from operating electronics to keep the spacecraft warm. The thermal blanketing – 18 layers of Dacron mesh cloth sandwiched between aluminized Mylar and Kapton film – also helped to protect the craft from micrometeorites.
X-rays
Kapton is also commonly used as a material for windows of all kinds at X-ray sources (synchrotron beam-lines and X-ray tubes) and X-ray detectors. Its high mechanical and thermal stability and high transmittance to X-rays make it the preferred material. It is also relatively insensitive to radiation damage.
3D Printing
Kapton and ABS adhere to each other very well, which has led to widespread use of Kapton as a build surface for 3D printers. Kapton is laid down on a flat surface and the ABS is extruded on to the Kapton surface. The ABS part being printed will not detach from the build platform as it cools and shrinks, a common cause of print failure by warping of the part.
Kapton tape is also commonly used to secure components such as thermocouples to the hot end of the plastic extruder. This helps to prevent detachment of the thermocouples, which can lead to runaway overheating of the nozzle, and fires.
| |
Q:
What are the most commonly encountered languages of Golarion?
Pathfinder campaign starting soon, I'm playing a human arcanist with high intelligence, which lets me take a bunch of languages.
So far I have Common (automatic), Thassilonian (from Scholar of the Ancients trait), Goblin and Giant (at GM recommendation), and I need to pick 3 more.
It seems the setting has dozens of languages, which I suppose is realistic. Which ones are most likely to be useful in practice? The campaign starts off in Sandpoint, if that makes a difference.
A:
Aside from the options you've listed so far, the most obvious option is Varisian, the regional language in the area around Sandpoint. There's also Shoanti, another regional language used in the same country.
Beyond that, some of the most widely-spoken languages are:
Draconic is used by kobolds, lizardfolk, and some spellcasters as well as dragons.
Dwarven, Elven, and Orc come up regularly, partly because each of those races have their own countries. These are also the most common races that I've seen to not speak Common (I haven't seen any halflings or gnomes who didn't know Common).
Sylvan is nice for speaking with fey and some plants, which are usually more open to negotiate than other creatures you encounter while adventuring.
Aklo is a common language for monsters. That may or may not be useful, depending on how much your group favors negotiation vs. combat.
Tien is essentially Common on the western continent of the Dragon Empires, but you're not likely to find many speakers around Sandpoint.
Similarly, Polyglot is widely spoken on the southern continent, but not much around Sandpoint.
That said, there's a slight difference between the most widely spoken languages and the languages that you're most likely to use. Many of the creatures summoned by spells like summon monster and planar binding are celestials, demons, and elementals. While you don't need to speak to these creatures for them to help you in battle, it can be very useful (e.g., summon an air elemental to fly up and scout for you). Those languages are:
Celestial
Abyssal
Infernal
Ignan
Aquan
Auran
Terran
Elementals in particular often speak only their planar language.
| |
When you go through this chapter, you will find a great deal of information on how to identify and create learning plans to meet the needs of students with learning disabilities. The instructors present the lessons to you in an informative and illustrative manner, and you can take the lesson quizzes to assess your knowledge on what you have just learned. Topics that are presented to you include:
- Informal and formal ways of assessing for learning disabilities
- Formative assessments
- The Response to Intervention (RTI) process
- Early reading intervention programs
- Personalized learning profiles for students
- The Learning Disabilities Instructional Support Planning Process (LDISPP)
- Individualized Education Plans (IEP)
- Parental involvement in IEP's
How It Helps
- Details strategies: You'll be presented with different assessment strategies that can be used to properly identify students with special needs.
- Reviews intervention types: These lessons will help you learn about the importance of early intervention and different types of early intervention programs so you can implement them in your classroom.
- Enhances awareness: Learning the importance and function of an IEP can help you to work with parents to create and implement this important document.
Skills Covered
When you finish working through these lessons, you will have the resources to:
- Identify the types of assessments that are used to identify the needs of special needs students
- Learn about the strategies that are used when a Response to Intervention is implemented
- Recall the role of early reading intervention programs and how they are beneficial
- Develop specific learning profiles to meet the needs of each student
- List the steps of the LDISPP process
- Understand the purpose of IEPs and understand how to incorporate parental input when creating them
1. Formal & Informal Assessments for Learning Disabilities
Teachers should use both formal and informal assessments to determine interventions for learning disabilities. This lesson will discuss both informal and formal methods of determining academic skill development and identifying students with special needs.
2. What is Formative Assessment? - Strategies & Examples
Formative assessment can help teachers plan the most effective instruction. In this lesson, you'll learn what formative assessments are, why they are important, and multiple strategies that you can implement in the classroom.
3. What Is Response to Intervention (RTI)? - Tiers & Strategies
The Response to Intervention process, or RTI, was designed and implemented in public schools as an attempt at early intervention for students with exceptional educational needs. In this video, we will look at the basics of this process.
4. Early Reading Intervention: Programs & Purpose
This lesson highlights early reading intervention programs designed to support students who are at risk for failure in reading. It also discusses why intervention is important.
5. Creating & Using Personal Learning Profiles for Students
In this lesson we will discuss how to create and use personal learning profiles for students. We will cover what these profiles should include and how that information can enhance an individualized approach to reaching students.
6. Learning Disabilities Instructional Support Planning Process: Definition & Uses
If you work with students who have learning disabilities, then you might be pursuing ways to support them in the classroom. This lesson defines and discusses the Learning Disabilities Instructional Support Planning Process.
7. Individualized Education Plan (IEP): Function, Purpose & Guidelines
The Individualized Education Plan is a critical document for children who receive special education services. In this video, we will take a brief look at the development and function of this important document.
8. Incorporating Parental Input in Individualized Education Programs
When developing a students' Individual Education Program, or IEP, educators must consider parental feedback. This lesson describes methods of involving parents in the IEP process and gives examples of ways teachers can foster parental involvement.
Earning College Credit
Did you know… We have over 160 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.
To learn more, visit our Earning Credit Page
Transferring credit to the school of your choice
Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you. | https://study.com/academy/topic/assessing-monitoring-students-with-learning-disabilities.html |
Flat-panel displays are electronic viewing technology used to enable people to see happy (still pictures , moving pictures , text , or other visual material) in a ranks of entertainment , consumer electronics , personal computer , and mobile devices , And Many kinds of medical , transportation and industrial equipment . They are far and away from traditional cathode ray tube (CRT) television sets and video displays and are usually less than 10 centimeters (3.9 in) thick. Flat-panel displays can be divided into twodisplay device categories: volatile and static. Volatile displays require that pixels be periodically electronically refreshed to retain their state (eg, liquid-crystal displays (LCD)). A volatile display only shows an image when it has battery or AC power hands . Static flat-panel displays rely on materials whose color states are bistable (eg, e-book reader tablets from Sony ), and as such, flat-panel displays retain the text or images on the screen when the power is off. As of 2016, flat-panel displays have almost completely replaced old CRT displays. In many 2010-era applications, specifically small portable devices such aslaptops , mobile phones , smartphones , digital cameras , camcorders , point-and-shoot cameras , and pocket video cameras , any display disadvantages of flat-panels (as compared with CRTs) are made up for by portability advantages (thinness and lightweightness).
Most 2010s-era flat-panel displays use LCD and / or LED technologies. Most LCD screens are back-lit as color filters are used to display colors. Flat-panel displays are better and more efficient than conventional TVs from earlier eras. The highest resolution for consumer-grade CRT TVs was 1080i ; in contrast, many flat-panels can display 1080p gold even 4K resolution . As of 2016, some devices that use flat-panels, such as tablet computers , smartphones and, less common, laptops, use touchscreens, a feature that allows users to pick up the screen by clicking on the screen. Many touchscreen-enabled devices can display a virtual QWERTY or numeric keyboard on the screen, to enable the user to type words or numbers.
A multifunctional monitor ( MFM ) is a flat-panel display That HAS additional video inputs (more than a typical LCD monitor ) and is designed to be used with a variety of external video sources, Such As VGA input, HDMI input from a VHS VCR or video game console and, in some cases, a USB input or card reader for viewing digital photos ). In many instances, an MFM also includes a TV tuner , making it similar to a LCD TV that offers computer connectivity.
History
The first engineering proposal for a flat panel TV was by General Electric as a result of its work on radar monitors. [ when? ] Their publication of their findings gives you the basics of flat-panel TVs and monitors. But GE did not continue with the R & D required and never built a working flat panel at that time. The first generation flat-panel display Was the Aiken tube , Developed in the early 1950s and Produced in limited numbers in 1958. This saw Some use in military systems have a heads up display, but standard technologies overtook its development. Attempts to commercialize the system for home television use in the marketplace. The Philco Predicta featured a relatively flat (for its day) cathode ray tube setup and would be the first commercially released “flat panel” upon its launch in 1958; the Predicta was a commercial failure. The plasma display panel was invented in 1964 at the University of Illinois , according to The History of Plasma Display Panels. The first active-matrix addressed by Peter Brody’s Thin-Film Devices Department at Westinghouse Electric Corporation in 1968. In 1977, James P Mitchell prototyped and later demonstrated what he calls the monochromatic flat panel LED television display LED display . As of 2012 , 50% of global market share in flat-panel display (FPD) is produced by Taiwanese manufacturers at AU Optronics and Chimei Innolux Corporation .
Common types
Liquid crystal displays
Liquid crystal displays (LCDs) are lightweight, compact, portable, cheap, more reliable, and easier on the eyes than cathode ray tube screens. LCD screens use a thin layer of liquid crystal, a liquid that exhibits crystalline properties. It is sandwiched between two electrically conducting plates. The top plate has transparent electrodes deposited on it, and the back plate is illuminatedso that the viewer can see the images on the screen. By applying controlled signals across the plates, various segments of the liquid crystal can be activated, in their light diffusing or polarizing properties. These segments are either transmitted or block light. An image is produced by passing light through the liquid crystal segments of the viewer. They are used in various electronics like watches, calculators, and notebook computers.
Liquid crystal displays with light-emitting diode (LED) backlighting
Some LCD screens are backlit with a number of light-emitting diodes (LEDs). LEDs are two-lead semiconductor light sources that resemble a basic “pn-junction” diode , except that LED’s also emits light. This form of liquid crystal display is the most prevalent in the 2010s. The image is still generated by the LCD.
Plasma panels
A plasma display consists of two glass plates separated by a thin gap filled with a gas such as neon. Each of these plates has several parallel electrodes running across it. The electrodes on the two plates are at right angles to each other. A voltage applied between the two electrodes one on each plate causes a small segment of gas at the two electrodes to glow. The glow of gas segments is maintained by a lower voltage than is always applied to all electrodes. In the 2010s, plasma displays have been discontinued by numerous manufacturers.
Electroluminescent panels
In an electroluminescent display (ELD), the image is created by applying electrical signals to the plates which makes the phosphor glow.
Organic light-emitting diode
An OLED (organic light-emitting diode) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound which emits light in response to an electric current. This layer of organic semiconductor is between two electrodes; typically, at least one of these electrodes is transparent. OLEDs are used to create digital displays in devices such as television screens, computer monitors, mobile phone systems such as mobile phones, handheld game consoles and PDAs. A major area of research is the development of OLED devices for use in solid-state lighting applications.
Quantum dot light emitting diode
QLED- QLED Gold Quantum Dot LED is a flat panel display technology introduced by Samsung under this trade mark. Other television set manufacturers such as Sony have used the same technology to enhance the backlighting of LCD Television in 2013. Quantum dots create their own unique light when illuminated by a light source of shorter wavelength such as blue LEDs. This kind of LED TV Introduced by Samsung Enhances the color gamut of LCD panels, Where the picture is still generated by the LCD. In the view of Samsung, quantum dot displays for large-screen TVs are expected to become more popular than the OLED displays in the coming years. This is surprising becauseSamsung Galaxy devices such as smartphones are mainly equipped with OLED displays manufactured by Samsung as well. Samsung states on their website that the QLED TV they produce can determine what part of the display needs more or less contrast. Samsung also announced a partnership with Microsoft that will promote the new Samsung QLED TV.
Volatile
Volatile displays require that pixels be periodically refreshed to retain their state, even for a static image. As such, a volatile screen needs electrical power, or from the hands of electricity (being plugged into a wall socket ) or a battery to maintain an image on the display or change the image. This is a second time. If this is not done, for example, if there is a power outage , the pixels will gradually lose their coherent state, and the image will “fade” from the screen.
Examples
The following flat-display technologies have been commercialized in 1990s to 2010s:
- Plasma display panel (PDP)
- Active-matrix liquid-crystal display (AMLCD)
- Rear projection : Digital Light Processing (DLP), LCD, LCOS
- Electronic paper : E Ink , Gyricon
- Light-emitting diode display (LED)
- Active-matrix organic light-emitting diode (AMOLED)
- Quantum dot display (QLED)
Technologies that were extensively researched, but their commercialization was limited or abandoned
- Active-matrix Electroluminescent display (ELD)
- Interferometric modulator display (IMOD)
- Field emission display (FED)
- Surface-conduction electron-emitter display (SED, SED-TV)
Static
Static flat-panel displays rely on materials whose color states are bistable . This means that the image they hold requires no energy to maintain, but instead requires energy to change. This results in a much more energy-efficient display, but with a tendency towards slow refresh rates, which are desirable in an interactive display. Bistable flat-panel displays are beginning deployment in limited applications (Cholesteric displays, manufactured by Magink, in outdoor advertising; electrophoretic displays in e-book reader devices from Sony and iRex; anlabels).
See also
- Computer monitor
- Display motion blur
- Electronic paper
- FPD-Link
- Flexible display
- Large-screen television technology
- LED-backlit LCD television
- Mobile display
- Sony Watchman
- Stereoscopy 3D displays requiring no special glasses
- Touch panel
- Transparent display
References
- Jump up^ “Proposed Television Sets Would Feature Thin Screens.” Popular Mechanics, November 1954, p. 111.
- Jump up^ William Ross Aiken,”History of the Kaiser-Aiken, Thin Cathode Ray Tube”, IEEE Transactions on Electron Devices, Volume 31 Issue 11 (November 1984), pp. 1605-1608.
- Jump up^ TV Plasma Science.org -The History of Plasma Display Panels
- Jump up^ Castellano, Joseph A. (2005). Liquid gold: the story of liquid crystal displays and the creation of an industry ([Online-Ausg.] Ed.). New Jersey [ua]: World Scientific. p. 176. ISBN 981-238-956-3 . | https://computerforum.eu/flat-panel-display/ |
---
abstract: 'Preconception-free analyses of the inclusive invariant transverse-momentum distribution data taken from the measurements of Au+Au collisions at $\sqrt{s_{NN}}=130$ GeV and $\sqrt{s_{NN}}=200$ GeV have been performed. It is observed that the distributions exhibit for $p_{T}\geq 2$ GeV/c remarkably good power-law behavior ($p_{T}$-scaling) with general regularities. This power-law behavior leads us in particular to recognize that the concept of centrality, albeit its simple appearance, is rather complex; its underlying geometrical structure has to be understood in terms of fractal dimensions. Experimental evidences and theoretical arguments are given which show that the observed striking features are mainly due to geometry and self-organized criticality. A simple model is proposed which approximately reproduces the above-mentioned data for the “suppression” without any adjustable parameter. Further heavy-ion collision experiments are suggested.'
author:
- 'MENG Ta-chung [^1]'
- 'LIU Qin [^2]'
bibliography:
- 'apssamp.bib'
title: '**Power-law behavior observed in $p_{T}$-distributions and its implications in relativistic heavy-ion collisions**'
---
Inclusive invariant $p_{T}$-distributions for charged hadrons in Au+Au collisions at $\sqrt{s_{NN}}=130$ and 200 GeV have been measured and published by STAR [@1; @2] and by PHENIX [@3] over a broad range of centrality. Such $p_{T}$-distributions for neutral pions are also given by PHENIX [@4]. All these experiments [@1; @2; @3; @4] show that the hadron yields differ appreciably at high and medium $p_{T}$ in central collisions
![Inclusive invariant $p_{T}$-distribution data [@1; @2] for $p_{T}\geq 2$ GeV/c in $\log$-$\log$ plots. Black and white indicate 130 and 200 GeV respectively.[]{data-label="fig1"}](fig1){width="48.00000%"}
relative to peripheral collisions and to the nucleon-nucleon reference. What do these observations, usually known as “suppression” [@5], tell us? Are they related to the yet-to-be-found “quark-gluon-plasma (QGP)”? If yes, how? In order to obtain an unbiased physical picture to start with, we begin with preconception-free data-analyses. We then summarize the results, and discuss their implications.
In [*the first part*]{} of this paper, we report on the result of such analyses. Within the measured kinematical region $0<
p_{T}<12$ GeV/c, $\sqrt{s_{NN}}=130$ GeV and $\sqrt{s_{NN}}=200$ GeV, the inclusive invariant $p_{T}$-distributions of $(h^{+}+h^{-})/2$ for centrality-selected Au+Au, and those for p+p interactions exhibit power-law behavior for $p_{T}\geq 2$ GeV/c (cf. Fig. 1). The results can be summarized as follows. $$\frac{1}{2\pi
p_{T}}\frac{d^{2}N}{dp_{T}d\eta}|_{\eta=0}(p_{T}|Au+Au;
p_{c})\propto p_{T}^{-\lambda_{AuAu}(p_{c})},$$ $$\frac{1}{2\pi
p_{T}}\frac{d^{2}N}{dp_{T}d\eta}|_{\eta=0}(p_{T}|p+p)\propto
p_{T}^{-\lambda_{pp}},$$ where the power-indices (the $\lambda$’s) are positive real numbers, and $p_{c}$ characterizes the centrality-bins (in percentile) which stand for the different degrees of departure from the most central collision. The experimental values of the $\lambda$’s obtained from the STAR data [@1; @2] at $\sqrt{s_{NN}}=130$ GeV and 200 GeV for different $p_{c}$-bins are shown in Fig. 2. The results from the PHENIX data [@3; @4] (will be reported in a more extensive paper elsewhere [@6]) show similar characteristic properties.
As we can see in Fig. 2, for a given $p_{c}$-bin, the $\lambda$-value at $\sqrt{s_{NN}}=200$ GeV coincides with the corresponding one at $\sqrt{s_{NN}}=130$ GeV. Furthermore, the $\lambda$-value for the most peripheral ($p_{c}\rightarrow 100\%$) case is very much the same as $\lambda_{pp}$’s. Note that the $\lambda$-values increase from the most peripheral value, $\lambda_{AuAu}(p_{c}\rightarrow100\%)\approx \lambda_{pp}$, with decreasing $p_{c}$ to the $\lambda$-value for the most central (center-on-certer) collision $(p_{c}\rightarrow 0\%)$ in a monotonous manner. In this connection it is useful to consider the ratio of both sides of Eqs. (1) and (2): $$\frac{d^{2}N/p_{T}dp_{T}d\eta|_{\eta=0}(p_{T}|Au+Au;p_{c})}{d^{2}N/p_{T}dp_{T}d\eta|_{\eta=0}(p_{T}|p+p;inel.
or NSD)}\propto p_{T}^{-\lambda(p_{c})}.$$ The quotient, which is a completely experimental quantity, on the left-hand-side of this equation, will hereafter be referred to as $Q(p_{T},p_{c})$; and the values of the exponent on the right-hand-side, $$\lambda(p_{c}) =\lambda_{AuAu}(p_{c})-\lambda_{pp},$$ are dipicted in Fig. 3. They are directly obtained from the data points shown in Fig. 2.
In [*the second part*]{} of this paper, we propose a simple model. We show how the power-law behavior can be understood, and how $\lambda_{AuAu}(p_{c})$ and $\lambda_{pp}$ in Eqs. (1) and (2) can be estimated. The model is based on geometry and self-organized criticality (SOC) [@7; @8]. As we shall see, both geometry and SOC contribute powers in $p_{T}$ to the distributions shown in Eqs. (1) and (2). The relevant facts and arguments are given below:
![The power-indices, $\lambda_{AuAu}(p_{c})$ and $\lambda_{pp}$, evaluated by measuring the slopes in Fig. 1 are plotted as function of $p_{c}$.[]{data-label="fig2"}](fig2){width="46.00000%"}
\(A) Geometry: Let us first recall the well-known observation made by Rutherford [@9] on large-momentum-transfer scattering, and a less-known observation made by Williams [@10] in which the following has been pointed out: Ordinary space-time concepts are useful for the semiclassical description of high-energy scattering processes, [*provided that*]{} the de Broglie wavelength of the projectile is short compared to the linear dimension of the scattering field, [*and provided that*]{} the corresponding momentum transfer which determines the deflection is not smaller than the disturbance allowed by the uncertainty principle. Through a simple realistic estimation, we can, and we did, convince ourselves that all these conditions [*are indeed fulfilled*]{} for Au+Au and p+p collisions at $\sqrt{s_{NN}}\geq 130$ GeV and $p_{T}\geq 2$ GeV/c. Furthermore we note that the corresponding phase-space factors can be estimated by making use of the uncertainty principle in accordance with Refs. [@9] and [@10].
\(B) SOC: It is well-known that approximately $50\%$ of the kinetic energy of every fast moving hadron is carried by its gluonic content and that the characteristic properties of the gluons, in particular, the direct gluon-gluon coupling prescribed by the QCD Lagrangian, the confinement, and the nonconservation of gluon numbers, can and should be considered as more than a hint that systems of interacting soft gluons are open dynamical complex systems which are far from thermal and/or chemical equilibrium. Taken together with the observations [@7; @8] made by Bak, Tang, and Wiesenfeld (BTW), these facts strongly suggest the existence of SOC and thus the existence of BTW avalanches in gluonic systems [@11; @12].
According to SOC, a small part of such BTW avalanches manifests themselves in the form of color-singlet gluon clusters $c_{0}^{\star}$, and that they can be readily examined [@11; @12] experimentally in inelastic diffractive scattering processes [@13]. This is because the interactions between the
![The power-index $\lambda (p_{c})$ defined in Eq. (4) plotted as function of $p_{c}$. Data are from Refs. [@1; @2].[]{data-label="fig3"}](fig3){width="47.00000%"}
struck $c^{\star}_{0}$ and any other color singlets are of Van der Waal’s type which are much weaker than color forces at distances of the order of hadron radius. In fact, in order to check the existence and the properties of the $c^{\star}_{0}$’s, a systematic data analysis has been performed [@12], the result of which shows that the size distribution $D_{S}(S)$, and the lifetime distribution $D_{T}(T)$ of such $c^{\star}_{0}$’s indeed exhibit power-law behavior $D_{S}(S)\propto S^{-\mu}$, $D_{T}(T)
\propto T^{-\nu}$, where $\mu$ and $\nu$ are positive real constants. Such characteristic features are known as “the fingerprints of SOC” [@7; @8]. These fingerprints imply in inelastic diffractive scattering, the size S of the struck $c^{\star}_{0}$ is proportional to the directly measurable quantity $x_{P}$, which is the energy fraction carried by “the exchanged colorless object” in such processes, the existing data [@13] show $D_{S}(x_{P}) \propto x_{p}^{-\mu}$, where $\mu
=1.95\pm 0.12$ [@11; @12].
By considering inelastic diffractive scattering [@11; @12], we were able to check—and only able to check—the existence and properties of the color-singlet gluon clusters. But, due to the observed SU(3) color symmetry, most of such gluon clusters are expected to be color multiplets which will hereafter be denoted by $c^{\star}$’s. Furthermore, in accordance with the experimentally confirmed characteristic features of the BTW theory, the SOC fingerprints in gluon systems should not depend on the dynamical details of their interactions, in particular, not on the details about the exchanged quantum numbers in their formation processes. This implies that $D_{S}(S)$ and $D_{T}(T)$ of the $c^{\star}$’s are expected to have [@14] not only the same power-law behavior but also the same power as that of their color-singlet counterparts observed in inelastic diffractive scattering processes [@11; @12].
The fact [@13] that quarks can be knocked out of protons by projectiles whenever large-momentum-transfer between projectiles and targets take place, has prompt us to propose [@14] that $c^{\star}$’s can also be “knocked out” of the mother proton by a projectile provided that the corresponding transfer of momenta is large enough where the knocked-out $c^{\star}$’s may have “color-lines” connected to the remnant of the proton. What we show now is that the observed power-law behavior in Eq. (2) can be quantitatively described by the product of the probability distribution(s) of the knocked-out $c^{\star}$’s and the phase-space factors associated with the knock-out processes.
Recall that processes of inclusive high-$p_{T}$ jet-production, p+p$\rightarrow$jet+$X$, at high energies are dominated by two-jet events; and that in a SOC-based model [@14], such jets are produced in two-step-processes. In Step 1: A quark $q$ ($q_{v}$ or $q_{s}$ or $\bar{q_{s}}$) in one of the colliding nucleon collides with a quark $q$ ($q_{v}$ or $q_{s}$ or $\bar{q_{s}}$) in the other nucleon where an amount of $p_{T}$ is transferred in the plane in which the two nucleons in form of thin contracted objects meet each other, and in which large-$p_{T}$ quark-quark scattering takes place. In Step 2: Since the two scattered $q$’s and/or $\bar{q}$’s are in general space-like (because of the large $p_{T}$), the easiest way for them to escape the confinement region is each “catches” a suitable time-like (in order to provide the high-$p_{T}$ $q$ or $\bar{q}$ with sufficient energy) anticolor BTW-avalanches, $c^{\star}$’s, which in accordance with the SOC-picture exist in abundance in their neighborhood. This is how a color-singlet jet is created. A scattered $q$ or $\bar{q}$ can also combine with a colored $c^{\star}$ to form a jet or a fan which is connected with other colored object(s) through color-lines. This is how color multiplet jets (or fans) can be produced. Hence, in the proposed picture the invariant cross section $Ed^{3}\sigma/dp^{3}$ is expected to have the following factors.
\(i) A phase-space factor that describes the chance for the two quarks ($q$ or $\bar{q}$, $\cdots$) which initiate Step 1 to come so close to each other in space that they can exchange a large $p_{T}$ ($\approx E_{T}$). This phase-space factor can be estimated by making use of the uncertainty principle and the two observations mentioned in (A) above. By choosing the $z$ axis as the collision axis, $p_{T}$ will be in (or near) the $xy$ plane. The chance for two constituents ($q$ or $\bar{q}$, $\cdots$) moving parallel to the $z$ axis to come so close to each other in the $xy$ plane such that an amount $p_{T}$ can be transferred is approximately proportional to the size of the corresponding phase space $\Delta x\Delta y \sim (\Delta p_{x})^{-1}(\Delta
p_{y})^{-1}\sim p_{T}^{-1}p_{T}^{-1}= p_{T}^{-2}$.
\(ii) Since each jet is associated with a to be knocked-out gluon cluster $c^{\star}$, which has energy comparable with $E_{T}$, $Ed^{3}\sigma/dp^{3}$ is expected to be proportional to the square of the probability $D_{S}$ to find such a $c^{\star}$. The size S of BTW avalanches is directly proportional to $x_{p}$, thus proportional to the energy $E_{T}$ it carries. Furthermore, since $E_{T}\approx p_{T}$ for high-energy jets [@14], we have: $$D_{S}(x_{p})\propto D_{S}(E_{T})\propto p_{T}^{-\mu}.$$ This means, we expect to see a factor $p_{T}^{-2\mu}$ in the invariant cross section $Ed^{3}\sigma/dp^{3}$.
\(iii) Having in mind that the scattered quarks are in general space-like, two-step-processes are expected to take place only when there are suitable $c^{\star}$’s in the surroundings immediately after the first step. The probability of having sufficient $c^{\star}$’s around, wherever and whenever two constituents meet during the p+p collision, is guaranteed when the c.m.s of one proton meets that of the other. Hence, phase-space considerations w.r.t time requires a factor $(\Delta t)^{2}\sim
E_{T}^{-2}\sim p_{T}^{-2}$.
Hence, for p+p collisions, we expect to see $Ed^{3}N/dp^{3}\propto
Ed^{3}\sigma/d^{3}p\propto p_{T}^{-2-2-2\mu}$. By taking the lower limit of $\mu $, we obtain: $$\frac{1}{2\pi
p_{T}}\frac{d^{2}N}{dp_{T}d\eta}|_{\eta=0}(p_{T}|p+p)\propto
p_{T}^{-7.66}$$ which is in reasonable agreement with the data [@2].
Next, we focus our attention to the [*empirical*]{} result described by Eqs. (3) and (4) together with Fig. 3. Note that according to Eq. (3), the quotient $Q(p_{T},p_{c})$ stands for the chance to find a large-$p_{T}$ charged hadron in Au+Au collisions within a given $p_{c}$ range; and this chance is measured in “units” of the chance in finding a similar large-$p_{T}$ hadron in p+p collisions. We now take a closer look at the straight lines, on which the data-points lie in the log-log plots of Fig. 1, and note the fact that the slopes depend only on $p_{c}$—independent of $\sqrt{s_{NN}}$. This has to be considered as a strong hint at the possible distinguished role played by geometry in describing/understanding such collision processes. Hence, it is useful not only to recall the facts and the arguments mentioned in (A) and those in (i) above, but also to recall that the word “centrality” $p_{c}$ is in fact very much involved: Experimentally [@1; @3] it is determined by measuring the multiplicities of produced hadrons; but, since the notion of “[*departure from the center-on-center case*]{}” is geometrical, it is expected to be describable in terms of geometry, in particular in terms of impact parameters, $b$’s. These facts and arguments have led us to propose the following picture. High-$p_{T}$ jet-production processes in relativistic heavy-ion (AA) collisions can be viewed as an ensemble of corresponding jet-production processes in binary nucleon-nucleon (NN) collisions. The observed effects depend significantly on collision-geometry.
Since every AA event corresponds to a $b$-parameter (note that the reverse is not true), an ensemble of collision events corresponds to a set of $b$-parameters. By choosing the $z$-axis as the collision axis where the centers of the two colliding nuclei are located at (-b/2,0) and (b/2,0), on the $x$-axis of the $xy$-plane in every event, we obtain point sets of impact parameters. It is on such point sets, [*the geometrical support*]{}, we study the above-mentioned $p_{T}$-distributions. Having the observations made by Rutherford [@9] and Williams [@10] in mind \[cf. (A) and (i) above\], the relation $\Delta x\sim (\Delta
p_{x})^{-1}\sim p_{T}^{-1}$ obtained by using the uncertainty principle tells us the following. For every measured value $p_{T}$, there is an interval $\Delta x$; and it is with [*this precision*]{} in the corresponding spatial coordinate that the probability $Q(p_{T},p_{c})$ \[precisely speaking $Q(\Delta
x,p_{c})$ on its geometrical support\] of finding high-$p_{T}$ charged hadrons can be measured.
In the proposed picture based on SOC and geometry, we are not (at least not yet) in a position to make predictions for $Q(\Delta
x,p_{c})$ or its geometrical support—not even the dimensions of such object! But fortunately, we know how to measure them! Thank the master-mathematicians: K. Weierstrass, G. Cantor, H.von Koch, F. Hausdorff, $\cdots$, P. Lévy and B. Mandelbrot [@15], we learned how to use the box-counting technique. Due to the facts and the arguments given in (A) and (i) above, we know that the length of the boxes in our case are of the order $\Delta x\sim
(\Delta p_{x})^{-1}\sim p_{T}^{-1}$ which implies: $\Delta x$ becomes smaller and smaller for larger and larger $p_{T}$. Hence the observed $p_{T}$-scaling tells us that the result of this box-counting is nothing else but the result summarized in Eq. (3) which can also be written as $Q(\Delta x,p_{c})\propto (\Delta
x)^{\lambda(p_{c})}$. Since this observation is independent of the positions of the boxes in each $p_{c}$-bin, by normalizing the probabilities $Q(\Delta x,p_{c})$, the number of boxes, $N(\Delta
x,p_{c})$, needed to cover the produced hadrons distributed on the geometrical support is proportional to the inverse of $Q(\Delta
x,p_{c})$. That is: $N(\Delta x,p_{c})\propto (\Delta
x)^{-\lambda(p_{c})}$. Hence, in the limit of large $p_{T}$, thus small $\Delta x$, $\lambda(p_{c})$ is the corresponding fractal dimension of the geometrical support which consists of set of impact parameter points within each given $p_{c}$-bin. This means, in the proposed model, we expect to see that the inclusive invariant $p_{T}$-distributions for $p_{T}\geq 2$ GeV/c in any kind of relativistic heavy-ion (AA) collisions satisfy $$\frac{1}{2\pi p_{T}}\frac{d^{2}N}{dp_{T}d\eta}|_{\eta
=0}(p_{T}|AA;p_{c})\propto p_{T}^{-\lambda_{NN}-\lambda(p_{c})}$$ where $\lambda_{NN}\approx7.66$, and the $\lambda(p_{c})$’s are the fractal dimensions of the point-set of impact parameters.
It would be exciting to see further experiments with larger $p_{T}$-values, at higher energies and with other kinds of colliding nuclei. Such experiments will not only serve the general goal of QGP-search, but also, in particular, be able to check whether the empirical regularities are indeed as general as the existing data seem to suggest, and to check whether/how concepts and methods of Complex Sciences in particular those borrowed from Fractal Geometry and SOC are helpful in understanding Relativistic Heavy-Ion Physics.
The authors thank XU Nu for explaining the experiments of STAR Collaboration to us. We thank LIANG Zuo-tang and XU Nu for their critical remarks and useful suggestions. We also thank LAN Xun and LIU Lei for helpful discussions and KeYanChu of CCNU for financial support. This work is supported by the National Natural Science Foundation of China under Grant No. 70271064.
[s2]{} C. Adler [*et al.*]{}, Phys. Rev. Lett. [**89**]{}, 202301 (2002).
J. Adams [*et al.*]{}, Phys. Rev. Lett. [**91**]{}, 172302 (2003).
K. Adcox [*et al.*]{}, Phys. Rev. Lett. [**88**]{}, 022301 (2002).
S.S. Adler [*et al.*]{}, Phys. Rev. Lett. [**91**]{}, 072301 (2003).
The precise definition of “suppression” can, e.g., be found in Refs [@1; @2; @3; @4] and the references herein.
Q. Liu, L. Liu, X. Lan and T. Meng (in preparation).
P. Bak, C. Tang, and K. Wiesenfeld, Phys. Rev. Lett. [**59**]{}, 381 (1987); P. Bak, C. Tang, and K. Wiesenfeld, Phys. Rev. A [**38**]{}, 364 (1988).
P. Bak, [*How Nature Works*]{} (Springer, New York, 1996); H. J. Jensen, [*Self-Organized Criticality*]{} (Cambridge University Press, Cambridge, UK, 1998).
E. Rutherford, Philos. Mag. [**XXI**]{}, 669 (1911).
E. J. Williams, Rev. Mod. Phys. [**17**]{}, 217 (1945).
T. Meng, R. Rittel, and Y. Zhang, Phys. Rev. Lett. [**82**]{}, 2044 (1999).
C. Boros, T. Meng, R. Rittel, K. Tabelow, and Y. Zhang, Phys. Rev. D [**61**]{}, 094010 (2000).
See, e.g., H. Abramowicz and A. Caldwell, Rev. Mod. Phys. [**71**]{}, 1275 (1999); A. M. Cooper-Sarkar, R.C. E. Devenish, and A. de Roeck, Int. J. Mod. Phys. A [**13**]{}, 3385 (1998), and references therein.
J. Fu, T. Meng, R. Rittel and K. Tabelow, Phys. Rev. Lett. [**86**]{}, 1961 (2001).
B.B. Mandelbrot, Science [**155**]{}, 636 (1967). B.B. Mandelbrot, [*The Fractal Geometry of Nature*]{}, W.H. Freeman, N.Y. G.A. Edgar, [*Classics on fractals*]{}, Westoiew, 2004.
[^1]: Email address: [email protected]; [email protected]
[^2]: Email address: [email protected]
| |
Getting injured will really put a damper on your good vibes, so be sure to follow these instructions.
- Inspect the bike prior to the riding to make certain that all parts are operating properly.
- Ensure that Adjustment Knobs (for seat height, fore and aft and handlebar) are tight and do not interfere with the rider’s range of motion during class.
- The maximum weight on the bike should not exceed 350 pounds.
- Keep hands, feet and objects free of moving parts of the bike at all times.
- To stop your bike, you should always gradually stop and try to avoid sudden stops. In the case of emergency to stop immediately press down on the resistance knob.
- Never turn the wheel by hand.
- Listen to your body at all times and ride at the pace that feels right for you.
- If you feel dizzy, lightheaded, have difficulty breathing or have a tightening in your chest, bring your bike to a gradual stop and ask for assistance.
- Stay hydrated and drink throughout the ride. Take as many breaks as your body needs.
- Always have some resistance on the bike so that the pedals do not rotate freely.
- Do not attempt to do movements or change positions fast before you have practiced them at slower speeds. Stay in control of the bike at all times.
- Do not use the bike without proper footwear. Never ride in bare feet. The bike pedals are compatible with SPD and Look clips.
- Never remove your feet while the bike is still in motion.
- Focus on form and posture throughout the ride.
- Keep your bike clear of obstructions on the floor (i.e. clothes etc.)
- If the bike is not operating correctly, please slow the pedals to a controlled stop, dismount the bike and inform the instructor.
- Do not dismount the bike until the pedals have fully stopped. Use the Resistance Adjustment Knob to slow the pedals to a controlled stop before you dismount the bike.
- After each use of the bike, please wipe down the bike.
- Keep children away from the bike. Parts that move and appear dangerous to adults can appear safe to children.
- Children under 4’11 should not ride the bike. The bike is designed for riders 4’11 and above. | https://cycletiquepgh.com/bike-safety-instructions/ |
PMP sample quizz based on the PMP exam. 25 Random questions. This is should take you about half an hour to do.
You are having some home renovation done. The project should take five days and cost €1,500 per day to complete. After 3 days the project is 30% complete and €5000 has been spent. What is the estimate to complete.
You and the vendor are in a dispute about the work within the project. The vendor is demanding payment for work they completed. You disagree with their demands. What is the likely outcome of this scenario?
You are the project manager for your organization. Your management team is determining which project should be initiated based on the present value of two projects. Project A will be worth $750,000 in three years. Project B will be worth $ 478,000 in two years. What is the present value of Project A if the interest rate is six percent?
You are working with management on the project planning processes. They want to know why you’re spending time on risk management planning so early in the project planning. Which one of the following is the best response to management’s concern?
Risk management planning increases the probability of success for the other risk management processes.
Risk management planning must happen before any other planning activities.
You feel, as the project manager, that the project has too many risks to be successful.
A project sponsor is studying the project contract and going through the narrative description of products and services to be supplied under contract. He is also meeting key stakeholders and Subject Matter Experts to evaluate whether or not the project is worth the required investment. Which of the following documents would be created as an output in the process?
You are managing a project to deliver 12 engines at a budgeted cost of 60m over 12 months. You are now in month 4 and you have completed 5 engines and spent 25m. What is the SPI and status of your project.
What is the SPI and Status of the project. This one is from the memory of a Deloitte Ireland employee who too the exam in March 2017.
After awarding contract to one of the sellers, you realize you have missed a clause for delay in the contract and want to modify it. How should you proceed further?
Sam is mid way through working on a project with few options for accelerating project completion. Additional resources are not available, the budget is severely constrained and the project must deliver key objectives sooner than the schedule currently shows possible. Which of the following options would Sam consider first to meet the deadlines.
During software code inspection in a major development project, one of the project management team identified frequent occurrences of critical programming errors. These errors are scattered across the software and occur without a pattern. Which tool is most likely to help the team identify areas of error to focus on.
You project is running very much on track up to now but during execution you realise that key resources promised earlier are now not available. Which of the following is the best option.
You are working on a project to build a new runway at Dublin Airport. You have reached the planned half way mark. The total planned cost at this stage is fifty million euro. The actual work that has been completed is valued at 40 Million. You have already spent one billion Euro on the project (Sound Right ?) . What is the CPI?
The Change Control Board has recently approved a scope change. This seems to be a regular occurrence on this large project, you know that scope change might come about as a result of all of the following except which one?
begin work on a project management plan.
confirm that all the stakeholders have contributed to the scope.
You are one year into a three year multimillion dollar project. The project CPI =.91 and the project SPI is 1.15. The Project is only earning $.91 for every dollar spent, while it is 15% ahead of schedule. As a result, the project manager has assembled the project team to review options for correcting the budget overage.
Which of the following would best address the budget overage issue?
Tom the builder (General Contractor or Main Contractor) and project manager has recently been been on an up-skilling course organised by the Institute of structural engineers. Tom is working with you to renovate you local school and is keenly aware of key delivery dates and how important it is to keep to those dates in order to gain full grant aid from the local education board. Tom designs the schedule and adds feeding buffers to important sections of the schedule. What learning was Tom most likely applying from his recent course.
Your next door neighbour is a team member on a project as a business analyst. He mentions to you that he had met with their project manager today to talk about a really good idea he had for a useful change to the project. He expresses frustration to you because he fully expected approval to go ahead with the change, but instead ,he was requested to write a report documenting the specific benefit on the change. As a project manager yourself what would be the most appropriate response?
agree with your neighbour that the project manager is just being unreasonable since the benefit documentation is really the project manager responsibility to.
Tell him you would ask the same for your team member. PM’s need to analyze the benefits of the change vs the cost and compare them to other possible changes.
Your neighbour should do what was asked because this short of information must be given to the project sponsor to make the change.
In the Monitoring and Controlling process group, one of the primary goals is to monitor and control the project work. What is another equally important and major goal of the monitoring and control process?
In your project, there have been several changes in the cost and schedule estimates and the original estimating assumptions are no longer valid. What is the Estimate at Complete for your project?
Quality assurance is needed in every project based on your organizational process assets and enterprise environmental factors. Which of the following statements best defines quality assurance?
The project performance is measured and evaluated, and corrective actions are applied to improve the product and the project.
You are the project manager for a construction project. One of the identified risks within the project has a 20 percent chance of happening. If the risk occurs, it will cost your project an additional $150,000. Given this, what is the contingency amount you’ll need for this risk event? | https://www.althris.com/quizzes/pmp-sample-quizz/ |
Probe after people who never took Covid tests were sent SMS with ‘their results’
The health ministry has launched an investigation into allegations of bogus Covid-19 test results, after a number of people who never had the test were nevertheless alerted by clinical laboratories of the ‘result’.
Speaking at the House watchdog committee on Thursday, Health Minister Constantinos Ioannou said he had instructed his permanent secretary to investigate the claims, documented in a draft report by the audit office.
Auditor-general Odysseas Michaelides said four people reported to his office that they received an SMS alerting them of the ‘result’ of their Covid test, which they had never actually taken. Two of these four individuals later filed a written complaint to the audit office.
The ‘results’ in question happened to be negative.
The health ministry has since confirmed that the two individuals receiving the bogus alerts were included in the test results data reported by the lab to the government.
“This shakes confidence in the system,” Michaelides told MPs.
For his part, Ioannou said that to date, 154,000 lab tests have been carried out, with a cumulative 991 (prior to Thursday’s results) positive coronavirus cases.
Christina Yiannaki, the health ministry’s permanent secretary, said the government has yet to make any payments to clinical labs, covering the cost of the Covid tests.
Payments would be made once the ministry combs through the invoices and completes its probe.
The auditor-general’s report covers the period up until when 96,287 tests were carried out, for a total cost of €7,506,933. Of the 12 accredited labs that did the tests, one in particular had performed 69 per cent of the tests, worth €4.81m.
It was suggested in parliament that the bogus test result alerts may be due to a foul-up, as some labs had earlier been given a batch of mobile numbers to call.
In addition to the false SMS alerts, the auditor-general also looked at the Covid test prices and their fluctuations through time.
At the start of the epidemic in Cyprus, the prices cited by private labs ranged from €120 to €170.
The health minister said that, at the time, only one private-sector lab could generate large numbers of tests daily; the Microbiology Laboratory at Nicosia general hospital was not up to speed.
Ioannou said because it was felt that an open tender might lead to a monopoly situation, the ministry set a reference charge of €110 for the Covid test, which was the price used by the Cyprus Institute of Neurology and Genetics.
Subsequently, and as more labs were accredited for the test, the price came down. As time passed, the lowest charge recorded for the Covid test was €50.
MPs also discussed another finding by the auditor-general, relating to the government’s procurement of masks.
The audit office flagged the process, noting for example that during an initial invitation for offers, one company had proposed selling for 49 cents per mask. Whereas this price was rejected as being “unreal,” later on the contract was awarded for a price even higher than that, 52 cents per mask.
A second attempt was made to seek offers; this time, the auditor-general said, two companies “emerged out of nowhere” vying for the contract.
These two companies had never previously participated in public tenders for the provision of medical products.
Ultimately, a contract for the masks was awarded for €4.7m, at 52 cents a mask.
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abstract: 'We investigate the structure of norm-preserving and linear but not necessarily surjective operators on variable-exponent, discrete Lebesgue spaces. A certain class of isometries, novel to this work, are especially considered; this class completely coincides with all isometries when the Lebesgue space is classical, i.e. of a fixed-exponent. For said isometries it is shown that their actions are completely determined by pairs consisting of set-mappings and bounded functions on ${\mathbb{N}}$. This result recovers the previously-known structure of isometries on fixed-exponent spaces as a special case. In the second part, we show that another wide class of operators, including shift operators, are only isometric under very restrictive conditions on the exponent sequence. Together these results serve to highlight the striking similarities and yet radical differences between isometric operators on fixed- and variable-exponent spaces.'
address: |
Department of Mathematics\
State University of New York College at Cortland\
Cortland, NY 13045-0900
author:
- 'Philip M. Gipson'
title: 'Isometric Operators on Variable-Exponent Discrete Lebesgue Spaces'
---
Introduction
============
The structure theory of isometric operators on the discrete Lebesgue spaces $\ell^p$ has been completely understood for some time. For $p=2$, the well-known Wold decomposition provides a thorough framework for understanding isometric operators on Hilbert space. For $p\not=2$, the work of Lamperti [@lamperti] provides a total description of isometric operators on general function spaces, including the Lebesgue spaces as specific examples.
The variable-exponent Lebesgue spaces, denoted here by ${\ell^{(p_n)}}$, form one natural generalization of the spaces $\ell^p$. The technical details for constructing these spaces will be left for Section \[prelims\], but the core idea is quite simple (and immediately conveyed by their name): allow the exponent used for norm-calculations to vary across orthogonal subspaces.
Because the $\ell^p$ spaces, and their norms in particular, have different behavior for $p>2$, $p<2$ and $p=2$, we might expect that variable-exponent spaces whose exponent sequence takes values in $[1,2)$ will exhibit different properties than those whose exponent sequence has values in $(2,\infty)$, or those whose exponents could take values in both ranges. Because of this, we will narrow our investigation to only those variable-exponent spaces ${\ell^{(p_n)}}$ with $1\leq p_n<2$ for all $n\in{\mathbb{N}}$ or with $p_n>2$ for all $n\in{\mathbb{N}}$. In the latter case we will not necessarily assume that the exponent sequence is bounded.
Our primary result in the first part is Theorem \[mylampthm\]. It gives a general structure theorem for “isomodular" operators (a class of isometries, see Definition \[isomodulardef\]) on ${\ell^{(p_n)}}$ spaces whose exponent sequence satisfies either of the restrictions discussed above. This provides a strong similarity with the theory of isometric operators on classical Lebesgue spaces $\ell^p$, $p\not=2$.
If $(p_n)$ is such that either $p_n\in[1,2)$ for all $n\in{\mathbb{N}}$ or $p_n\in(2,\infty)$ for all $n\in{\mathbb{N}}$, and if $S:{\ell^{(p_n)}}\to{\ell^{(p_n)}}$ is an isomodular operator then there exists a regular set isomorphism $T$ and a function $h\in\ell^\infty$ such that $$(Sx)_n=h(n)(Tx)_n$$ for all $x\in{\ell^{(p_n)}}$ and $n\in{\mathbb{N}}$. Furthermore, $|h(n)|\leq1$ for all $n\in{\mathbb{N}}$.
In the second part we consider linear operators $S_\theta$ on variable-exponent spaces ${\ell^{(p_n)}}$ which arise from measure-preserving actions $\theta$ on ${\mathbb{N}}$. This class of operators is of special interest because it contains the unilateral shift. Our primary result in this part is Theorem \[shiftisometry\] and it gives a complete characterization of when such operators are isometric.
For given $\theta$ and $(p_n)$, the operator $S_\theta$ restricts to an isometry on ${\ell^{(p_n)}}$ if and only if $p_n=p_{\theta(n)}$ for every $n\in{\mathbb{N}}$.
Background
==========
In this section we will provide the background required to understand Lamperti’s result for $\ell^p$ spaces, as it provides the inspiration for our investigation of the variable-exponent Lebesgue spaces ${\ell^{(p_n)}}$. We will then provide a very specialized and narrow formulation of the theory of semimodular function spaces as they pertain to variable-exponent Lebesgue spaces.
Isometries on $\ell^p$, $p\not=2$
---------------------------------
We will use the notation $\mathcal{P}({\mathbb{N}})$ to denote the powerset of ${\mathbb{N}}$. The following definition is given in full in [@lamperti §3] and is here restated only for the set ${\mathbb{N}}$ with the counting measure.
\[regsetiso\] A *regular set isomorphism* (of ${\mathbb{N}}$) is a mapping $T:\mathcal{P}({\mathbb{N}})\to\mathcal{P}({\mathbb{N}})$ satisfying:
1. $T({\mathbb{N}}-A)=T{\mathbb{N}}-TA$
2. $T\left(\bigcup_{n=1}^\infty A_n\right)=\bigcup_{n=1}^\infty TA_n$
3. $TA=\emptyset\text{ if and only if }A=\emptyset$
for all $A,A_n\in\mathcal{P}({\mathbb{N}})$.
Because of condition (ii), it is clear that there is a one-to-one correspondence between regular set isomorphisms $T$ on the one hand and denumerable collections of pairwise-disjoint subsets of ${\mathbb{N}}$ on the other. Explicitly, if $A_1,A_2,...\in\mathcal{P}({\mathbb{N}})$ is a denumerable and pairwise-disjoint collection then $T:\{n\}\mapsto A_n$ extends to a regular set isomorphism in the natural manner.
Given a regular set isomorphism $T$ and an element $a\in\ell^p$ we define $Ta\in\ell^\infty$ by $$(Ta)_n=\begin{cases} a_k &\text{ when }n\in T\{k\} \\ 0 &\text{ otherwise }\end{cases}.$$ Note that unless the cardinalities of $T\{k\}$, $k\in{\mathbb{N}}$, are finite and uniformly bounded then $Ta$ is not guaranteed to be in $\ell^p$ itself.
[@lamperti Theorem 3.1, paraphrased]\[oglamperti\] Let $U$ be a linear operator on $\ell^p$, where $p$ is a positive real number not equal to 2, such that $$||Ua||=||a||\text{ for all }a\in\ell^p$$ (the norm is the usual $p$-norm). Then there exists a regular set isomorphism $T$ and an $h\in\ell^\infty$ such that $$Ua=hTa.$$
We have omitted a second portion of the Theorem statement concerning certain measure-theoretic properties of $h$ which are not of interest in the $\ell^p$ formulation.
A key part of Lamperti’s proof is the observation that an isometry $U$ will preserve orthogonality relations and, consequently, may be used to construct a collection of disjoint support sets which will define the regular set isomorphism. We will make use of a similar technique in our main result.
Variable Exponent Spaces {#prelims}
------------------------
For our understanding of the variable exponent spaces ${\ell^{(p_n)}}$ we will rely on the theory of *modular spaces*. Our reference for this topic will be the excellent book [@diening] by Diening et al.
For any set $A$, the set of all possible $A$-valued functions on ${\mathbb{N}}$ will be denoted $A^\infty$. An element $p\in A^\infty$ will be referred to as a *$A$-valued sequence* and we will use the common notations $p_n:=p(n)$ and $(p_n):=p$.
Let $p\in[1,\infty)^\infty$ (a $[1,\infty)$-valued sequence) be given and define $${\ell^{(p_n)}}:=\left\{a\in{\mathbb{C}}^\infty\ :\ \sum_{n\in{\mathbb{N}}}|a_n|^{p_n}<\infty\right\}$$ It is nontrivial to determine that this is a complex vector space [@diening Chapter 2]. The sequences $e_k$, $k\in{\mathbb{N}}$, defined by $(e_k)_n=\delta_{kn}$ (here $\delta$ is the Kronecker delta) form a basis set for ${\ell^{(p_n)}}$.
The norm on ${\ell^{(p_n)}}$ is given by $$||a||:=\inf\left\{\lambda>0\ :\ \sum_{n\in{\mathbb{N}}}\left|\frac{a_n}{\lambda}\right|^{p_n} \leq 1\right\}.$$
In addition to the norm, we will define a *modular* on ${\ell^{(p_n)}}$, denoted $\varrho$, by $$\varrho(a):=\sum_{n\in{\mathbb{N}}}|a_n|^{p_n}.$$
In the case when $p$ is a constant sequence we have that ${\ell^{(p_n)}}$ is precisely the classical Lebesgue space $\ell^p$ and the modular and norm have the simple relationship $||a||^p=\varrho(a)$.
In general, the modular and norm have only the relationship $$||a||=\inf\left\{\lambda>0\ :\ \varrho\left(\frac{a}\lambda\right)\leq 1\right\}.$$
In this more complicated situation it is not immediately clear whether norm-preserving, i.e. isometric, operators must necessarily preserve the modular. To that end, we offer the following definition:
\[isomodulardef\] A linear operator $S:{\ell^{(p_n)}}\to{\ell^{(p_n)}}$ will be called *isomodular* if $\varrho(Sa)=\varrho(a)$ for all $a\in{\ell^{(p_n)}}$.
Our first observation is that being isomodular is a stronger condition on an operator than being isometric.
\[isomodimpliesisomet\] If $S:{\ell^{(p_n)}}\to{\ell^{(p_n)}}$ is an isomodular operator then it is isometric.
For $a\in{\ell^{(p_n)}}$ and $\lambda >0$ we have $\varrho\left(\frac{a}\lambda\right)=\varrho\left(S(\frac{a}\lambda)\right)=\varrho\left(\frac{Sa}\lambda\right)$. Thus $\varrho\left(\frac{a}\lambda\right)\leq 1$ if and only if $\varrho\left(\frac{Sa}\lambda\right)\leq 1$. And hence $$||Sa||=\inf\left\{\lambda>0:\varrho\left(\frac{Sa}\lambda\right)\leq 1\right\}=\inf\left\{\lambda>0:\varrho\left(\frac{a}\lambda \right)\leq 1\right\}=||a||$$ as desired.
The converse statement is true in the special case of constant $(p_n)$, i.e. for classical $\ell^p$ spaces. This is a direct consequence of the simpler relation, $\varrho(a)=||a||^p$, between modular and norm which occurs in such spaces. It is currently unknown to us whether isometric operators are necessarily isomodular in general.
Isomodulars on Spaces with Restricted Exponents
===============================================
Throughout this section we will assume that $(p_n)$ is such that either $p_n\in[1,2)$ for all $n\in{\mathbb{N}}$ or $p_n\in(2,\infty)$ for all $n\in{\mathbb{N}}$. The motivations for such a restriction on the exponent sequence are the classical Clarkson inequalities [@clarkson] for the usual (fixed-exponent) Lebesgue spaces $\ell^p$. The Clarkson inequalities quoted below are in an expanded form due to Lamperti [@lamperti Corollary 2.1].
For $f,g\in \ell^p$ with $p>2$ we have $||f+g||^p+||f-g||^p\geq2||f||^p+2||g||^p$. If $p<2$ then the reverse inequality is true. In either case, equality occurs if and only if $fg=0$ almost everywhere.
Of course, if $p=2$ the Parallelogram Identity gives $||f+g||^2+||f-g||^2=2||f||^2+2||g||^2$ for any $f,g\in \ell^p$ regardless of orthogonality. Hence we explicitly exclude the possibility of our exponent sequences having 2 as a value.
Considering the above Proposition, for $z,w\in{\mathbb{C}}$ and $p>2$ we have $|z+w|^p+|z-w|^p\geq 2|z|^p+2|w|^p$ (and the reverse for $p<2$) with equality if and only if either $z=0$ or $w=0$. Therefore if $(p_n)$ is such that $p_n\in(2,\infty)$ for all $n\in{\mathbb{N}}$ and given $a,b\in{\ell^{(p_n)}}$ then $$|a_n+b_n|{^{p_n}}+|a_n-b_n|{^{p_n}}\geq2|a_n|{^{p_n}}+2|b_n|{^{p_n}}$$ with equality if and only if $a_nb_n=0$. It follows that $$\sum_{n\in{\mathbb{N}}}|a_n+b_n|{^{p_n}}+\sum_{n\in{\mathbb{N}}}|a_n-b_n|{^{p_n}}\geq2\sum_{n\in{\mathbb{N}}}|a_n|{^{p_n}}+2\sum_{n\in{\mathbb{N}}}|b_n|{^{p_n}}$$ with equality if and only if $a_nb_n=0$ for all $n\in{\mathbb{N}}$. From the definition we now have that $$\varrho(a+b)+\varrho(a-b)\geq2\varrho(a)+2\varrho(b)$$ with equality if and only if $ab=0$. The reverse inequality holds if $(p_n)$ is such that $p_n\in[1,2)$ for all $n\in{\mathbb{N}}$, including the strict equality condition. Taken together these observations result in the following lemma.
If $(p_n)$ is such that either $p_n\in[1,2)$ for all $n\in{\mathbb{N}}$ or $p_n\in(2,\infty)$ for all $n\in{\mathbb{N}}$, and $a,b\in{\ell^{(p_n)}}$ then $$\varrho(a+b)+\varrho(a-b)=2\varrho(a)+2\varrho(b)$$ if and only if $ab=0$.
Recall that for the usual $\ell^p$ spaces the relation between the norm and modular is $||a||^p=\varrho(a)$ for all $a\in\ell^p$. Hence the Lemma is a direct generalization, to ${\ell^{(p_n)}}$ spaces, of Lamperti’s version of Clarkson’s inequalities. Lamperti’s primary use of Clarkson’s inequalities was to conclude that isometric operators preserve orthogonal vectors. We find that isomodular operators, at least on spaces with restricted exponents, similarly preserve orthogonality.
\[ortho\] If $(p_n)$ is such that either $p_n\in[1,2)$ for all $n\in{\mathbb{N}}$ or $p_n\in(2,\infty)$ for all $n\in{\mathbb{N}}$, $S:{\ell^{(p_n)}}\to{\ell^{(p_n)}}$ is isomodular, and $a,b\in{\ell^{(p_n)}}$ are such that $ab=0$ then $(Sa)(Sb)=0$ as well.
Since $S$ is isomodular we have that $\varrho(Sx)=\varrho(x)$ for all $x\in{\ell^{(p_n)}}$. It follows, using the previous Lemma, that $$\varrho(Sa+Sb)+\varrho(Sa-Sb)=\varrho(a+b)+\varrho(a-b)=2\varrho(a)+2\varrho(b)=2\varrho(Sa)+2\varrho(Sb).$$ Using the previous Lemma again we immediately conclude that $(Sa)(Sb)=0$.
The basis elements $e_n\in{\ell^{(p_n)}}$ are, naturally, orthogonal, and so by the above proposition their images $Se_n$ under an isomodular operator are orthogonal as well. It follows that the support sets $$\operatorname{support}(Se_n):=\{k\in{\mathbb{N}}\ :\ (Se_n)_k\not=0\}$$ must be pairwise disjoint.
If $(p_n)$ is such that either $p_n\in[1,2)$ for all $n\in{\mathbb{N}}$ or $p_n\in(2,\infty)$ for all $n\in{\mathbb{N}}$ and if $S:{\ell^{(p_n)}}\to{\ell^{(p_n)}}$ is an isomodular operator then the assignments $$T:\{n\}\mapsto\operatorname{support}(Se_n)$$ extend to a regular set isomorphism $T$ of ${\mathbb{N}}$.
Recall from the discussion following Definition \[regsetiso\] that if $T$ is a regular set isomorphism of ${\mathbb{N}}$ then it extends to a map (also called $T$) from ${\ell^{(p_n)}}$ to $\ell^\infty$.
We now have a sufficient preparation to state and prove our main result:
\[mylampthm\] If $(p_n)$ is such that either $p_n\in[1,2)$ for all $n\in{\mathbb{N}}$ or $p_n\in(2,\infty)$ for all $n\in{\mathbb{N}}$, and if $S:{\ell^{(p_n)}}\to{\ell^{(p_n)}}$ is an isomodular operator then there exists a regular set isomorphism $T$ of ${\mathbb{N}}$ and a function $h\in\ell^\infty$ such that $$(Sx)_n=h_n(Tx)_n$$ for all $x\in{\ell^{(p_n)}}$ and $n\in{\mathbb{N}}$. Furthermore, $|h(n)|\leq1$ for all $n\in{\mathbb{N}}$.
Define the regular set isomorphism $T$ as in the previous Proposition. Then the extension $T:{\ell^{(p_n)}}\to\ell^\infty$ is given by $$(Ta)_n=\begin{cases} a_k &\text{ when }n\in \operatorname{support}(Se_k)\\ 0 &\text{ otherwise }\end{cases}$$ where the values are well-defined precisely because the support sets are pairwise disjoint.
Consider $a,b\in{\ell^{(p_n)}}$. Then each term of $T(a-b)$ is either zero or a difference of like terms, $(Ta-Tb)_n=a_k-b_k$, $n\in\operatorname{support}(Se_k)$. It follows that $||T(a-b)||_\infty\leq ||a-b||_\infty\leq||a-b||$. Hence $T:{\ell^{(p_n)}}\to\ell^\infty$ is continuous.
In particular, $(Te_m)_n=1$ if $n\in\operatorname{support}Se_m$ and 0 otherwise, i.e. $Te_m$ is the indicator sequence for the support set of $Se_m$. Hence for any $m\in{\mathbb{N}}$ we have $Se_m=Se_mTe_m$.
Consider that $||e_m||=1$ for each $m\in{\mathbb{N}}$, and so by Proposition \[isomodimpliesisomet\] $||Se_m||= 1$. Defining $h:=\sum Se_m$ we conclude that, because the $Se_m$ have pairwise disjoint support, $h\in\ell^\infty$. Further, for each $n\in{\mathbb{N}}$ we have that $|h(n)|=|(Se_m)_n|\leq ||Se_m||=1$ for some $m\in{\mathbb{N}}$.
Consider that for given $k\in{\mathbb{N}}$ we have $$Se_m=Se_mTe_m=\sum_{m\in{\mathbb{N}}}Se_mTe_m=hTe_m.$$ By linearity this extends to sequences $a\in{\ell^{(p_n)}}$ with finite support. Such elements are dense in ${\ell^{(p_n)}}$ [@diening Corollary 3.4.10] and so the conclusion follows by the continuity of $T$.
Our theorem precisely recovers Lamperti’s result in the case when $(p_n)$ is constant, and evokes a result [@felmingjamison]\[Theorem 9.2.12\] for *surjective* isometries on a wider class or sequence spaces.
Operators Induced by Transformations of ${\mathbb{N}}$
======================================================
We have already seen that an isomodular operator is necessarily isometric. Since isomodular operators on variable-exponent spaces with restricted exponents are now known, per Theorem \[mylampthm\], to have a determined structure, so too do a certain class of isometries. The goal for our current section is to understand the structure of another potential class of isometries: shift operators.
The unilateral shift $S:{\mathbb{C}}^\infty\to{\mathbb{C}}^\infty$ is defined for each $a\in{\mathbb{C}}^\infty$ by $(Sa)_1=0$ and $(Sa)_{n+1}=a_n$ for $n\in{\mathbb{N}}$. For a general variable-exponent space ${\ell^{(p_n)}}\subset{\mathbb{C}}^\infty$ there is no guarantee that $S$ is a bounded operator, or even that $Sa\in{\ell^{(p_n)}}$ when $a\in{\ell^{(p_n)}}$.
\[example1\] Take $(p_n)=(1,2,1,2,...)$ and $a=(0,1,0,\frac12,0,\frac13,...)$. Then $a\in{\ell^{(p_n)}}$ but $Sa$ is not.
If $\Gamma:{\mathbb{N}}\to{\mathbb{N}}$ is a bijection then define a linear operator $S_\Gamma:{\mathbb{C}}^\infty\to{\mathbb{C}}^\infty$ where for each $a\in{\mathbb{C}}^\infty$ we have $(S_\Gamma a)_n=a_{\Gamma^{-1}(n)}$. When acting on a classical $\ell^p\subset{\mathbb{C}}^\infty$ these $S_\Gamma$ operators are isometric isomorphisms. However, there is no such guarantee when they act on a variable-exponent space.
Take $(p_n)$ and $a\in{\ell^{(p_n)}}$ as in Example \[example1\]. Set $\Gamma(n)=n-(-1)^n$. Then $S_\Gamma a\not\in{\ell^{(p_n)}}$.
Generalizing both previous concepts, consider operators $S_\theta:{\mathbb{C}}^\infty\to{\mathbb{C}}^\infty$, related to injective maps $\theta:{\mathbb{N}}\to{\mathbb{N}}$, which are defined by $$(S_\theta a)_n:=\begin{cases}a_{\theta^{-1}(n)} & n\in\theta({\mathbb{N}}) \\ 0 & \text{otherwise}\end{cases}$$ Notice that $S_\theta e_n=e_{\theta(n)}$ for each $n\in{\mathbb{N}}$; this could also be considered the defining feature of $S_\theta$.
\[shiftisometry\] For given $\theta$ and $(p_n)$, the operator $S_\theta$ restricts to an isometry on ${\ell^{(p_n)}}$ if and only if $p_n=p_{\theta(n)}$ for every $n\in{\mathbb{N}}$.
For necessity, let $a\in{\ell^{(p_n)}}$ be given and suppose that $p_{\theta(n)}=p_n$ for each $n\in{\mathbb{N}}$. Consider that $$||S_\theta a||=\inf_{\theta>0}\left\{\sum_{n\in{\mathbb{N}}}\left|\frac{(S_\theta a)_n}{\lambda}\right|^{p_n}\leq 1\right\}$$ For sufficiency the claim is trivial if $\theta$ is the identity mapping, so let $j\in{\mathbb{N}}$ be such that $\theta(j)\not=j$.
Consider the sequence $b:=2^{-\frac1{p_j}}e_j+2^{-\frac1{p_{\theta(j)}}}e_{\theta(j)}$. By definition we have that $$||b||=\inf\left\{\lambda>0\ :\ \frac{\lambda^{-p_j}}{2}+\frac{\lambda^{-p_{\theta(j)}}}{2}\leq 1\right\}.$$ As before, it must be that $||b||$ satisfies $\frac{||b||^{-p_j}}{2}+\frac{||b||^{-p_{\theta(j)}}}{2}= 1$, however since $p_j,p_{\theta(j)}\in[1,\infty)$ we conclude this is only possible when $||b||=1$.
If $||S_\theta b||=||b||=1$ then $\lambda =1$ is a solution to $$\left(\frac{2^{-\frac1{p_{j}}}}{\lambda}\right)^{p_{\theta(j)}}+\left(\frac{2^{-\frac1{p_{\theta(j)}}}}{\lambda}\right)^{p_{\theta(\theta(j))}}=1$$ thus $$2^{-\frac{p_{\theta(j)}}{p_j}}+2^{-\frac{p_{\theta(\theta(j))}}{p_{\theta(j)}}}=1.$$ Since the equation $2^x+2^y=1$ has the unique (real) solution $x=y=-1$ we must conclude that $p_j=p_{\theta(j)}=p_{\theta(\theta(j))}$.
Our Theorem partially recalls with the result in [@skorik] where it is shown that the bijective isometries of real-valued analogs to ${\ell^{(p_n)}}$ are precisely obtained from entry-value-preserving permutations of $(p_n)$ together with sign-changes.
The injection $\theta(n):=n+1$ yields $S_\theta=S$ the unilateral shift; and so we have the following:
The unilateral shift is isometric on ${\ell^{(p_n)}}$ if and only if $(p_n)$ is constant.
Similarly we find any multiple of the shift, $S^k$, is isometric on ${\ell^{(p_n)}}$ if and only if $(p_n)$ is periodic and the period divides $k$.
[1]{} . , [**40**]{} (1936), no. 3, 396–414.
Lebesgue and Sobolev Spaces with Variable Exponents. Lecture Notes in Mathematics, 2017. [*Springer-Verlag, Berlin*]{}, 2011.
. , [**8**]{} (1958), 459–466.
(Russian) . [**34**]{} (1980), 120–131, iv.
Isometries on Banach spaces. Vol. 2. Vector-valued function spaces. Chapman & Hall/CRC Monographs and Surveys in Pure and Applied Mathematics, 138. Chapman & Hall/CRC, Boca Raton, FL, 2008. x+234 pp
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The mile-high ceilings and starch-white walls paint the perfect contrast to the portraits hung on the wall. Splashes of color. Straight lines, tossed around on the paper. Oblong faces stretched for the onlooker’s gaze.
Four pieces, each distinct in appearance, each frame a human body, posing and looking out at the studio.
In front of the far right piece is a man with a colorful Jaxon hat on, struggling to proportionally align the portrait’s eyes with the rest of the face. This man is none other than the creator of these lively, meaningful pieces, Kris Hargis.
When we sat down to an interview about his creations, Kris began to tell me about his artistic past and how he got to be where he is now.
He has been studying and practicing his artistic abilities since he was an adolescent, focusing primarily on the self-portrait, like the one he was working on when I arrived.
In order to widen his artistic horizons, Kris attended the University of Kansas for his undergraduate degree, and then went to Boise State University for his master’s.
While at BSU, Kris was encouraged to step outside of the self-portrait, and he learned how to make bronze busts of his own head. For Kris, trying to connect to other humans was his specialization in art, and trying to form this relationship through a two-dimensional plane wasn’t enough. So, the three-dimensional human sculpture, like a bronze bust, became a way for him to explore this human connection.
While at BSU, Kris also became a studio assistant at Penland School of Craft, and he participated in Michael Dixon’s painting process and performance workshop. At the time, Dixon was a professor at Albion (and is now the department chair for the Art & Art History program at Albion). He suggested that Hargis apply to the artist residency program at Albion College. Hargis found out in April of 2016 that he was accepted and was ecstatic to be able to focus on his artistic work for three months.
Since January, Hargis has been at Albion, braving the blustery Michigan winter, while he works on his creative pieces. While here, he has been able to create four self-portraits.
Four pieces of art are more than he is usually able to put out in a short amount of time, considering each of his pieces is a tedious process. He looks into the mirror for hours, drawing what he sees in his reflection on a paper without looking at it.
Then, there is a lot of subtractive mark making, where bits of the piece that aren’t correct to his final image of the piece are removed. As he adds in more and more and tweaks different aspects, the piece slowly comes together.
Finally, he throws in color to the final image, all with a specific palette that he hopes evokes some feeling to both him and the onlooker. After a few days or weeks of working and everything is set how it is supposed to, highlights to the self-portrait are made, and the piece is seemingly completed.
However, Hargis believes the piece of art isn’t truly finished until there is this human-to-human connection between himself and the onlooker that was evoked from the piece.
“If you think of two squares of pavement and that little area in between, there’s some grass growing. That’s the interstice, the area in between. There’s me and then you, and the interstice is the us,” said Hargis, illustrating the connection between himself and the viewer.
Therefore, the interstice between Hargis’ art and the observer looking at the portrait is the emotion that is evoked from the portrait and is shared between Hargis and the observer, creating this human-to-human connection. This emotion is the grass between the two squares of pavement, which will create discussion between Hargis and the observer.
“My goal is that the viewer can come stand in front of these pieces, come into them with an open mind and an open heart and possibly receive a message, relate to that gaze or emotional qualities that the color palette gives, kind of inviting the viewer to become a part of the piece and finish it in a way,” said Hargis.
His creations from his time at Albion will be presented in a gallery showing called “Interstice” from February 24 through March 29 in the Munro Gallery at the Bobbitt Fine Arts Building. Hargis’s hope for this show is to engage the onlooker with the piece and to find some human-to-human bond over his self-portrait.
Kris is available for any questions, comments, critiques or conversations in his studio at the Fine Arts Building anytime Monday through Thursday, 2:30 to 4:30 p.m. Or you can contact him via email at [email protected]. More of his work can be found at www.kristianhargis.com or www.froelickgallery.com.
Photo courtesy of Kris Hargis.
“If you think of two squares of pavement and that little area in between, there’s some grass growing. That’s the interstice, the area in between. There’s me, and then you, and the other, and the interstice is the us,” said Hargis, illustrating the connection between himself and the viewer.
The part that I highlighted in bold – can this be removed? When we talked I mentioned there is me and you and the interstice. I know I mentioned me and others, but I do not want people to associate the condition and quality of Otherness.
Thank you so much for addressing this if possible. | https://www.albionpleiad.com/2018/02/spring-2018-artist-in-residence-kris-hargis/ |
College soccer is played with a clock that can be stopped when signaled to by the referee for injuries, the issuing of cards, or when the referee believes a team is wasting time. … In most professional soccer leagues, there is an up-counting clock with the referee adding stoppage time to the end of each 45-minute half.
How long are soccer halves in college?
Professional and college soccer games are 90 minutes long and are broken up into two 45-minute halves.
Are there timeouts in college soccer?
Timeouts are not permitted in college soccer. The only time a coach can use a stoppage in play to talk to his team is during the 15 minutes half time break.
How long is a college soccer season?
The 2020 NCAA Division I men’s soccer season is the 62nd season of NCAA championship men’s college soccer.
…
|2020 NCAA Division I men’s soccer season|
|Duration||Fall season: September 17 – November 22, 2020 Spring season: February 3 – May 17, 2021|
Can I play soccer in college with no experience?
People often ask if you can you play soccer in college with no experience. You do not want to be asking college coaches how to become a soccer player, but you can play soccer at a college if you have no experience in either high school or club soccer. … NCAA Division II Soccer – 181 men’s teams and 228 women’s teams.
How many D1 soccer players go pro?
Out of all of the college soccer players that play in the NCAA (National Collegiate Athletic Association) only 1.4 percent of players will make it onto a professional soccer teams’ roster.
Is it hard to play college soccer?
The recruiting process for college men’s soccer is very competitive. About 7.9% of high school men’s soccer players go on to play in college, and only about 1.1% go on to play for a Division 1 school. In addition to having athletic talent and good grades, it’s essential to take the recruiting process seriously.
How many substitutions can you have in soccer?
Usually, each team is allowed to make three substitutions, with seven players on the bench to choose from. Due to the current situation, every team is allowed to name nine players on the bench and make five changes during the match.
How many substitutions are allowed in college soccer?
NCAA college soccer allows up to 11 substitutions at a time. Players are also allowed one re-entry in the match, as opposed to professional soccer’s strict three-sub rule.
Is there time out in soccer?
There are no breaks in soccer, including timeouts. Each half lasts 45 minutes with a 15-minute break in between. Therefore, there is no time for commercials like in American sports. What’s considered out of bounds?
What is the best college for a soccer player?
Best Soccer Colleges
- Stanford University.
- University of North Carolina at Chapel Hill.
- University of California Los Angeles (UCLA)
- University of Virginia.
- Harvard University.
14 нояб. 2019 г.
Is there a mercy rule in college soccer?
The National Collegiate Athletic Association’s mercy rule provides, “Any time during the game, the playing time of any remaining period or periods and the intermission between halves may be shortened by mutual agreement of the opposing head coaches and the referee.” (NCAA Football Rule 3-2-2-a) NCAA Football Approved …
Do college soccer players get paid?
U.S. college soccer players do not get paid.
Can you walk-on a d1 football team?
NCAA Division II and III, NAIA schools and Junior colleges all welcome walk-ons. NCAA Division I colleges also offer tryouts but it tends to be more difficult. There have been a number of athletes who have walked on to Division I football, basketball and baseball teams. … You can walk-on at just about any college.
What percent of college athletes are walk-ons?
Being considered a walk-on is far more common in college sports than most families and athletes realize. According to the latest NCAA information, 46 percent of Division I athletes are walk-ons and 39 percent of Division II athletes are walk-ons.
How good do you have to be to play d1 football?
The NCAA requires a 2.5 grade-point average to qualify, but that’s the minimum. You don’t settle for the minimum on the field, so don’t in the classroom. You run the 40-yard dash in 4.5 seconds and can catch anything within five feet? | https://rightbankwarsaw.com/football-game/frequent-question-is-there-stoppage-time-in-college-soccer.html |
Be able to create a deeper sound on a Jews Harp by opening your throat.
Make different sounds and combinations with an open throat on a Jews Harp.
Remember the feeling of you yawning, that’s when your throat is open.
Try speaking while your throat is open and create a deep sound.
Now try this on a Jews Harp and make some combinations with the normal sound and a much deeper sound by opening your throat.
Practice further until you are comfortable. | https://www.didgeridoodojo.com/how-to-play-jaw-harp/jaws-harp-sounds/ |
The search box has become the de-facto “user interface” for interacting with data in the modern era. Virtually every website, app, and modern software interface relies upon or could benefit heavily from relevant search, and the Apache Lucene/Solr open source search project is the most deployed solution for delivering search across today’s top companies.
Come learn how to add automatically-learning and highly-relevant search to your applications from Trey Grainger, author of the books AI-Powered Search and Solr in Action and recognized industry expert in building intelligent search applications. You’ll learn how to use the Apache Lucene/Solr project to implement AI-powered search, though most the techniques learned in this workshop will also be applicable to other modern core search engine (Elasticsearch, Lucidworks Fusion, Open Distro for ES, Vespa, etc.)
This workshop assumes no prior knowledge of Lucene/Solr (we’ll provide an overview in the morning session), and we will approach learning from a capabilities and relevancy standpoint that is ideally suited for data scientists and application developers looking to implement intelligent features in their software (keyword matching, machine-learned ranking/learning to rank, word embeddings and dense vector search, personalized search, recommendations, semantic search, smart autocomplete, etc.). More technical product managers interested in these capabilities will also find this workshop quite helpful.
Agenda
Morning Session
● Introduction to Search
○ Search and the Inverted Index
○ Text-based relevancy ranking
○ Apache Lucene: High-performance text search engine library
○ Apache Solr: Modern, Distributed, Horizontally-Scalable, Search-first NoSQL database optimized for Information Retrieval
○ Overview of Key Features: Multilingual text analysis, Faceting & Analytics, Highlighting, Spelling Correction, Autocomplete, Sorting and Grouping, Geospatial Search, Complex Function Queries, Recommendations, Graph Queries and Traversals, Streaming Aggregations and SQL Query Support, Plug-ins, and many more
● Getting started with Solr
○ Installing and Running Solr
○ Overview of Admin UI, APIs, and Documentation
○ Indexing Data into Solr
○ Lab
● Text Analysis
○ Analyzers, Tokenization, and Token Filters
○ Natural Language Processing
○ Handling Language-specific and Multilingual Content
● Querying Basics
○ Lucene/Solr Query Syntax
○ Keyword, Boolean, Phrase and Proximity Queries
○ Range Queries
○ Filter Queries
○ Faceted Search
● Ranking Functions
○ Sparse vs. Dense Vector Search
○ Text Similarity Scoring with Cosine Similarity, TF-IDF, and BM25
○ Function Queries
○ Complex Ranking Functions
○ Domain and User-specific Ranking Functions
○ Lab
Lunch Break
Afternoon Session
● Balancing the Dimensions of User Intent
○ Content, User, and Domain Relevance
○ Semantic Search
○ Recommendations
○ Personalized Search
○ Knowledge Graphs
● Reflected Intelligence
○ Capturing and using user signals for relevance tuning
○ Collaborative Filtering for Recommendations
○ Learning to Rank (Machine-learned Ranking)
○ Automated Learning to Rank with Click Models
○ Lab
● Semantic Search
○ NLP for Search
○ Semantic Knowledge Graphs
○ Content-based Recommendations
○ Semantic Query Parsing and Entity Extraction
○ Concept Expansion and Disambiguation (term embeddings)
○ Natural Language Search with Knowledge Graphs
○ Machine learning strategies
■ Spelling corrections
■ Phrase detection
■ Head-tail analysis
■ Synonym detection
○ Lab
● Thought Vectors and Word Embeddings
○ Working with Embeddings
○ Implementing Dense Vector Scoring
○ Quantized Vectors and Hash Functions
○ Using Bert and Deep-learning-based Encoders
○ Lab
● Taking AI-powered Search to Production
○ Intro to Lucidworks Fusion
○ Search Relevancy Testing: Techniques and Metrics
○ The Continuous Learning Cycle
○ Lab
● Question / Answer Session on topics relevant to the attendees
Who should Attend?
● Data Scientists, Software Developers, and Product Managers interested in learning about information retrieval and how ML and AI can drive contextual, domain-aware, personalized results to users of search-driven applications
● People looking for an introduction to Apache Lucene/Solr, the most widely used search engine technology on the planet. Note that many of the concepts in the training also apply to other search engines, such as Elasticsearch, Lucidworks Fusion, Open Distro for ES, and Vespa, but this training and associated labs will target Lucene/Solr.
● Attendees will not be required to write code, but the workshop will contain labs that the instructor will walk through while attendees follow along. Programming knowledge, as well as familiarity with REST and HTTP, are needed if you want to go beyond the concepts and get hands-on experience with the labs yourself. The labs will primarily be implemented in Python in Jupyter Notebooks in order to appeal to both software developers and data scientists and to enable all attendees to easily follow along.
Who should NOT Attend?
-
Those looking for a detailed training on DevOps with Lucene/Solr or a deep dive into Lucene/Solr under the hood. This course is instead primarily focused on relevant search and automating the process of creating relevant search though machine-learning and feedback loops.
About the Instructor
Trey Grainger is the CTO at PreSearch, where he leads the development of a distribute Web3 Search Engine.
He is the author of AI-Powered Search and the co-author of Solr in Action, plus more than a dozen additional books, journal articles, and research publications covering industry-leading approaches to semantic search, recommendation systems, and intelligent information retrieval systems. Trey received his Masters in Management of Technology from Georgia Tech, studied Computer Science, Business, and Philosophy at Furman University, and studied Information Retrieval and Web Search at Stanford University. | https://www.southerndatascience.com/ai-powered-search22 |
Today, we are going to continue dividing but not just by 10, 100 and 1000.
Have a look at the In focus question below and decide how you could solve the problem.
Could you use your number bonds to break the numbers apart to make it easier to divide?
Are there any clues in the question that could help us break the numbers apart?
How about we look at the divisor? 3 is a divisor because 930 can be easily broken up into 900 and 30 and both of these numbers can be divided by 3.
900 divided by 3 = 300 and 30 divided by 3 is 10.
The final answer would be 310.
Have a look below to see how the problem can be solved using counters.
First, we need to look at the hundreds column. How many 3s are there in 900?
That’s right, there are 300
Next, how many 3s in 30?
That’s right there are 10.
Finally, how many 3’s in 0?
That’s right, there are 0.
Now, lets have a go at some of the questions in the Guided Practice. You will notice these questions are a little tricky as the numbers in the question do not always divide equally like they did in our previous example.
Lets look at 24 divided by 6.
We are still using the method above which is known as the bus stop method. You should remember this method from Year 4.
First, we need to write it out like I have shown you below.
Next, how many groups of 6 can we make from 2? The answer is 0 so we place a zero at the top and exchange the 2 into the tens column as shown below.
Then, we see how many groups of 6 we can now make from 24. If you know your times tables you will know the answer is 4.
Our final answer should look like this.
Now you are ready to complete some examples on your own.
Complete worksheet 17 in your home learning book. Take a picture of your work and email it to your teacher through purple mash.
You will need to show your working out using the bus stop method. Remember to set it out correctly. If you are un sure go back and have a look at the previous examples. | https://www.stoneyholme.lancsngfl.ac.uk/5b-maths-1/ |
What is Pre-Algebra?
Pre-Algebra is the study of everything after long division, up until you get just before polynomials in algebra. So it actually should include some algebra basics.
According to some math advisors whom we have consulted with - teachers and professors who have become frustrated with the "new math" or the Common Core math that is being pushed on school kids - there is an orderly, logical progression in learning mathematical skills. No matter how "relative" the new math publishers try to make things with funny videos or word problems using faddish lingo, you can't force the skills to be mastered. Some children might be able to "get through" a lesson or exam, they may even be able to score well on an assignment or exam, but retention is very difficult if concepts are taught out of order. The human brain processes information in specific ways, and again, math concepts need to be in the logical order that the brain will process the information - which will then produce the most retention. Retention is critical for advancing to higher math without frustration.
Go for mastery, versus a passing grade! It is critical when you are teaching math that you do not move forward until your child has mastered the concept. If your child gets a "B" in math, it doesn't mean they understand what they are doing. And if that B is because they missed a critical step, then they will likely struggle in their math career. Getting a "B" essentially is a signal that your child does not understand about 15 to 20 percent of the concepts.
Also remember that if your child does not do well in 6th grade math, it does not mean they are behind. Go back to these lists, and start from the beginning, and think of the progression as mastery, versus grade levels. Once they have mastered all three sections (A, B, and C) of the Pre-Algebra concepts below, they are ready for Algebra, which is 9th grade. So don't let grade levels intimidate you or tell you what your child cannot do.
BEFORE PRE-ALGEBRA
Here is the logical progression which must be mastered before pre-algebra:
From our director:
"When I taught remedial math to homeschoolers (kids who had been moved to Algebra who were struggling)...nearly 100% of them had to back all the way up to long division or right after long division when they were introduced to fractions. That is where they were rushed through..."
Keep in mind, that word problems or discussion questions involving math are absolutely essential to have that retention. From one of our members: "When I was in school, my instructors never made me do the word problems because I did so well on the drills (you know, 50 or 60 number problems in a chapter??) This caused a hindrance for me when I got into high school and was preparing to take the pre-college exams. I simply went blank on the word problems and I did not do well. I hated math. Hated it. Because I could not reason with it."
Drills, drills, and more drills will only teach your children to expect more drills. It doesn't mean they are liking what they are learning, which in our opinion interprets to - it doesn't mean they will retain. Discussion and application will strengthen retention. Now, the ACT and SAT exam (and most state exams) are primarily word problems. As of this date, those exams are still very relevant for kids wanting to get into college and to do well. So never skip the word problems! As a matter of fact, our experts suggest that you have the child do the word problems first, then the drills if they are needed. They should be doing way more word problems (sometimes called story problems) than worksheet drills.
As students work through division, be sure they fully understand long division BEFORE you introduce fractions. Fractions are essentially division problems, they just use a different order and different symbols than regular division or long division. There are some people who say you can teach a toddler fractions. Yes, you can to a degree. However, they don't understand fractions as a division problem because they haven't learned multiplication yet. Therefore later on, our experts say that they could have difficulty with more complicated fractions. So again, master long division before fractions.
Once your child has mastered long division, you are ready for pre-algebra (not just a passing grade, but they have mastered it), the logical order of pre-algebra is as follows, and can be divided into three sections. Some kids can do all of this in less than a year, for some it takes 2-3 years.
Master everything in this list - in order - before you go to list B.
NEW! List A and List B now have videos and worksheets as supplements for PLUS GOLD and Plus Legacy members to teach the concepts on this page - it has been extremely helpful for mastering pre-algebra as well as reviewing important concepts for students who are further along in algebra but are stuck. See below for the link to access the Pre-Algebra Mastery videos and worksheets!
After Part A, you will need to introduce probability and statistics, which again are essentially fractions. So it simply isn't logical to introduce probability and statistics before learning about fractions. This is also part of pre-algebra and is in order as follows:
A final area of what we consider pre-algebra is the ability to see patterns and to turn the concepts into graphs. Do it in this order as follows:
Note: This final section can be skipped if you are going to have your child do high school Algebra, because it's included in those texts to slow kids down in high school. The following list is considered "Algebra" in high school. However, if you are going to go from Pre-Algebra to college level Algebra, then you must master Section C. We teach more about dual credit college courses in our Homeschooling High School and Beyond Course for Plus members.
List A and List B now have videos and worksheets as supplements for PLUS GOLD and Plus Legacy members to teach some of the concepts on this page - it is not a complete curriculum, but has been extremely helpful for mastering pre-algebra as well as reviewing important concepts for students who are further along in algebra but are stuck. Videos and worksheets for list C are not available at this time. This content is for Plus Gold and Plus Legacy members only.
Once the child has mastered all of the above, then and only then are they ready to proceed to algebra. According to our experts, if your child has not mastered all of the above, then they will struggle in algebra and higher math. These concepts will also make geometry so much easier!
The following videos and articles are offered to PLUS members to help you teach math. They are a collection from guest speakers, our online conferences, and special articles in our archives - Enjoy! | http://barefootbigshots.com/toolbox/math/pre-algebra |
It is said that a Soviet oil rig fell into the crater in 1971, and a geologist decided to get rid of the rig by setting the pit on fire. The resulting gas-fed flames continue burning to this day.
What does a geologist do on an oil rig?
Petroleum geologists explore the Earth for oil and gas deposits. They analyze geological information to identify sites that should be explored. They collect rock and sediment samples from sites through drilling and other methods and test the samples for the presence of oil and gas.
What are geologists and engineers looking for when they explore for oil?
Finding oil and gas – petroleum geoscientists (geophysicists, geologists, and geochemists) work in multidisciplinary teams to decide where to perform seismic imaging (like an ultrasound of the Earth), collect and analyze seismic data, and analyze pre-existing drillhole data from wells to develop a detailed picture of …
What are the highest paying geology jobs?
Top employers and the average salary paid to geologists include: Conoco-Phillips ($134,662) Langan Engineering and Environmental Sciences ($92,016)
…
As of 2020, related jobs include:
- Environmental scientist ($69,705)
- Geophysicist ($108,232)
- Environmental engineer ($82,325)
- Scientist ($100,523)
- Staff scientist ($90,937)
Can a geologist work in an oil company?
In some cases, they work side-by-side with oil companies in the supervising of the oil extraction process. Geologists may be hired by engineering or environmental consulting firms; oil, gas, and mining companies; federal and state government agencies; and science centers and museums.
Who was the first person to drill out oil from beneath the surface of the earth?
Figure 1. Since 1859 when a man named Drake set up the first oil well in Pennsylvania, Americans have drilled for oil. How do oil companies extract (pull out) these tiny droplets away from the rock located thousands of feet underground?
How much does a geologist make on an oil rig?
According to 2016 statistics, the median salary for this professional is $112,143. The lowest 10% earned in the region of $61,500 and the highest 10% earned in excess of $223,759. Normal range for the majority of roles is between $85,002 and $104,733. Annual bonuses are between $2,682 and $45,933.
How did they find oil in the old days?
The earliest known oil wells were drilled in China in AD 347 or earlier. They had depths of up to about 800 feet (240 m) and were drilled using bits attached to bamboo poles. The oil was burned to evaporate brine and produce salt. … Petroleum was known as burning water in Japan in the 7th century. | https://nipexnig.com/gas/what-did-the-geologist-decide-to-get-rid-of-the-oil-rig.html |
An international team of astronomers has announced the discovery of 11 distant planets, bringing the number of known planets outside our solar system to 63.
One of the planets is in an Earth-like orbit around a sun-like star. It is located in what is known as the ?habitable zone,? where conditions would be ideal for the presence of liquid water, a necessary ingredient for life as we know it.
But like all the planets we have discovered so far, this one is a giant about the size of Jupiter. ?It may be orbited by one or more moons on which a more bio-friendly environment has evolved,? according to a spokesman for the European Southern Observatory. Saturn, Jupiter and Neptune, the giant planets in our solar system, all have multiple moons, some of which are thought to have saltwater oceans on them.
One of the new planets was the second one scientists have detected that has 3 stars. Anyone standing on one of these planets would get plenty of light and see 3 suns in the sky.
None of these planets have been observed directly?they have been detected by measuring the wobble they produce as they orbit their stars. Astronomers hope to discover other, smaller planets as more powerful observatories such as the Keck Interferometer come online.
NOTE: This news story, previously published on our old site, will have any links removed. | https://www.unknowncountry.com/headline-news/new-planets-found-one-in-life-zone/ |
Building an ecosystem-based approach to fisheries management requires knowledge of how climate and fishing induce changes in fish community structure over short and long time periods. It is recognized that investigating the internal structure of marine production systems, particularly in the form of species interactions, is as important as taking into account external factors such as environmental conditions and fishing activity. In this study, we used an individual-based spatially and temporally explicit multispecies model (OSMOSE) to explore the potential impacts of climate change and fishing on the dynamics of fish populations in the Strait of Georgia, Canada. In the OSMOSE model, the fate of all individuals of multiple fish species was modeled through their life cycles including changes in their spatial distribution, natural mortality, predation, starvation, growth, fishing mortality, and reproduction. Our simulations suggested research should consider the pathways through which environmental disturbances enter the ecosystem and interact with predator-prey dynamics and species life history in order to understand species’ responses to environmental changes and management actions. As an example, in the simulations Pacific herring was more sensitive to changes in copepod biomass than changes in phytoplankton biomass, and intensive fishing on Pacific herring decreased the overall fish production from the ecosystem. This study demonstrates the importance of using a model such as OSMOSE to explore scenarios that combine species interactions, fisheries management, and climate change. | https://seagrant.uaf.edu/bookstore/pubs/item.php?id=11932 |
Who’s at fault in a Shipping Lane collision?
Our reader is interested in whether the use of shipping lanes by a pleasure boat, or the failure to monitor radar or a VHF radio, could lead to a finding of fault in a collision. We will address those issues, but we should note the Navigation Rules (commonly referred to as the Rules of the Road) are not followed by vessel operators, or evaluated by courts, in a vacuum. All of the circumstances existing at the time must be considered, including visibility, weather, sea state, and the number, type, course and speed of vessels involved in the incident and other vessels in the immediate area at the time of the incident.
The most important thing to know about collisions at sea is that they are almost never deemed to be the responsibility of one party. This is in large part due to the application of Navigation Rule 5, which requires all boats to maintain a good lookout at all times, and Rules 2 and 8, which require all vessels to take steps to avoid collision even if they have the right of way in an encounter.
Since the burden for safety at sea is shared by all mariners, liability for damage caused by a collision at sea is attributed between various parties under a concept known as “comparative fault.” Under this system, each party will be required to bear some percentage of the total loss, based upon the percentage of fault allocated to them. The circumstances vary considerably from case to case, and the outcome will depend upon what the expert witnesses have to say about the actions of the parties. This is the umbrella under which all cases like this will be evaluated. With that in mind, we can look at our reader’s concerns.
“Shipping lanes” exist at the approaches to major bluewater ports and are clearly marked on nautical charts. Recreational vessels are not prohibited from entering a shipping lane. They are, however, required under Rule 10 of the Navigation Rules to exit them as quickly as possible and to cross them at as near as possible to a right angle. The yacht described by our reader would have been in violation of this rule if it was just loitering around or fishing — but assuming they were cruising through the lane on their way to Catalina, they would have been OK.
The reader correctly notes that proper form of communication between vessels in sight of each other would is by VHF radio. Initial contact is established on channels 13, 16, or under some circumstances Channel 70, depending on the circumstances and the equipment aboard the vessel. However, use and monitoring of VHF radio by vessels less than 20 meters in length (around 65 feet) is not required. Even if the yacht were larger than 65 feet in length, the failure to monitor the radio (whether due to the device being broken or another reason) would have been only one factor in evaluating liability for the incident under the comparative fault system.
Similarly, radar is not required on vessels less than 1,600 gross tons (which roughly translates to something the size of a large offshore oil supply vessel). However, pursuant to Navigation Rule 7, if a boat does have radar aboard, the crew must use it to avoid collision. In the incident described by our reader, the boat operator’s failure to use his radar would almost certainly have been deemed a factor in allocating fault between the two vessels.
Investigations into the cause of a collision may be conducted by insurance companies, the Coast Guard or another regulatory agency, or by expert witnesses in a lawsuit. Insurance investigators and expert litigation witnesses are, of course, unable to issue a citation to a boat operator who has violated a navigation rule. They can, however, determine that, in their opinion, a violation of the rules occurred, and that opinion may be used in litigation.
These types of violations don’t immediately lead to a conclusion of fault on the part of one party or another. Instead, the party who committed the violation must show how the violation could not have been a cause of the incident. And, even if they are not able to make such a showing, this would establish only a component of comparative fault. It would not render that party wholly at fault unless it was shown that the other side bore no responsibility at all.
Operating a vessel requires attention to numerous factors, and inattention to any one of those factors may lead to a collision. The allocation of fault in a collision is a complex endeavor that almost always requires the assistance of experienced experts, who are able to weigh all of the factors that may have contributed to the incident.
David Weil is licensed to practice law in the state of California and as such, some of the information provided in this column may not be applicable in a jurisdiction outside of California. Please note also that no two legal situations are alike, and it is impossible to provide accurate legal advice without knowing all the facts of a particular situation. Therefore, the information provided in this column should not be regarded as individual legal advice, and readers should not act upon this information without seeking the opinion of an attorney in their home state.
David Weil is the managing attorney at Weil & Associates (weilmaritime.com) in Long Beach. He is an adjunct professor of Admiralty Law at Loyola University Law School, a member of the Maritime Law Association of the United States and is former legal counsel to the California Yacht Brokers Association. If you have a maritime law question for Weil, he can be contacted at 562-438-8149 or at [email protected].
Ask your question online at thelog.com. | https://www.thelog.com/ask-the-attorney/who-s-at-fault-in-a-shipping-lane-collision-2016-04-20t09-04-01/ |
Long-term results of high-dose methylprednisolone in aplastic anemia.
Four males and two females, aged 13 to 57 years (median 22 years), with acquired severe aplastic anemia (AA) were treated with intravenous bolus of high doses of 6-methylprednisolone (MPL). Patients received MPL within a 30-day period at a dose of 20 mg/kg/day (3 days), 10 mg/kg/day (4 days), 5 mg/kg/day (4 days), 2 mg/kg/day (9 days), and 1 mg/kg/day (10 days). Within the first 3 months following MPL therapy, a response rate of 83%, assessed by means of increase in reticulocytes, neutrophils or platelets, was recorded in the group: two cases showed partial response and three improvement. The 3-month, and 1-, 2- and 3-year survival of the group was 67%, 50%, 33% and 33%, respectively. Neither the presence of reticulocytopenia or thrombocytopenia prior MPL therapy, nor age, gender, etiology of AA or time between diagnosis and initiation of MPL influenced survival. In contrast, neutrophil counts before MPL treatment had a strong prognostic value. Patients with less than 0.5 x 10(9)/L neutrophils had a median survival of 4.2 months (range 1.2 to 5.2 months) as compared to the 36.1 months median survival (range 12.1 to 36.8 months) of patients whose neutrophil counts were greater than 0.5 x 10(9)/L. Follow-up data suggest that the administration of androgens two months after MPL therapy did not modify survival. It is concluded that high-dose MPL is useful in the treatment of some patients with acquired severe AA, particularly in those with greater than 0.5 x 10(9)/L neutrophils who are not candidates for bone marrow transplantation.
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Q:
MongoDB Get Single Object Nested in Array of Objects in Array of Objects
How do you access a single object nested in an array of objects that is nested in another array of objects, based on a few property values, something like this in pseudo code:
SELECT DAY=1 WHERE _id=5a3469f22dc3784bdd9a6190 AND MONTH=12
Mongoose model schema is listed below. As required, subdocuments are listed higher than their corresponding parents, dailySchedulesSchema being the highest:
var dailySchedulesSchema = new mongoose.Schema({
day: Number,
dayStart: Number,
firstBreakStart: Number,
firstBreakEnd: Number,
lunchStart: Number,
lunchEnd: Number,
secondBreakStart: Number,
secondBreakEnd: Number,
dayEnd: Number,
workDuration: Number
});
var monthlyScheduleSchema = new mongoose.Schema({
month: {type: Number, required: true },
dailySchedules: [dailySchedulesSchema]
});
var employeeSchema = new mongoose.Schema({
name: {type: String, required: true},
surname: {type: String, required: true},
email: {type: String, required: true},
phone: {type: String, required: true},
occupation: {type: String, required: true},
status: {type: Boolean, required: true},
monthlySchedule: [monthlyScheduleSchema]
});
This is the employee entry in the database I am trying to work on.:
"_id" : ObjectId("5a3469f22dc3784bdd9a6190"),
"name" : "Eric",
"surname" : "K. Farrell",
"email" : "[email protected]",
"phone" : "864-506-7281",
"occupation" : "Employee",
"status" : true,
"monthlySchedule" : [
{
"month" : 12,
"dailySchedules" : [
{
"day" : 1,
"dayStart" : 480,
"firstBreakStart" : 600,
"firstBreakEnd" : 615,
"lunchStart" : 720,
"lunchEnd" : 750,
"secondBreakStart" : 870,
"secondBreakEnd" : 885,
"dayEnd" : 1020,
"workDuration" : 480
},
{
"day" : 2,
"dayStart" : 540,
"firstBreakStart" : 630,
"firstBreakEnd" : 645,
"lunchStart" : 750,
"lunchEnd" : 780,
"secondBreakStart" : 870,
"secondBreakEnd" : 885,
"dayEnd" : 1050,
"workDuration" : 480
}
]
}
]
}
The route itself for getting single day is: "/employees/:employeeid/:month/:day" .
While I managed to access the parent documents(like listing all employees), I was unable to list specific subdocument entries(like specific day schedule for that employee) - mongoose has either been returning all of the existing day schedules in the month or nothing at all:
(...)
var sendJsonResponse = function(res, status, content){
res.status(status);
res.json(content);
}
(...)
module.exports.empDayReadOne = function(req, res){
var monthParam = req.params.month;
var employeeid = req.params.employeeid;
var dayParam = req.params.day;
Emp
.aggregate([
{$match: {$and: [{'monthlySchedule': {$elemMatch: {$exists: true} } }, {_id: employeeid }] } },
{$unwind:'$monthlySchedule'},
{$unwind:'$monthlySchedule.dailySchedules'},
{$match:{ $and:[ {'monthlySchedule.dailySchedules.day': dayParam},{'monthlySchedule.month': monthParam} ] } }
])
.exec(function(err, dailySchedule){
if(dailySchedule){
sendJsonResponse(res, 200, dailySchedule);
} else if(err){
sendJsonResponse(res, 400, err);
return;
} else {
sendJsonResponse(res, 404, {"message": "This day has no schedules added."});
return;
}
});
};
A:
You can try below aggregation query.
The below query first $filters monthlySchedule which returns the array with the matching month array element followed by second filter to retrieve the matching day element in dailySchedules array.
$arrayElemAt to convert the array with single element into a document.
db.collection_name.aggregate([
{"$match":{"_id":ObjectId("5a3469f22dc3784bdd9a6190")}},
{"$project":{
"dailyschedule":{
"$arrayElemAt":[
{"$filter":{
"input":{
"$filter":{
"input":"$monthlySchedule",
"cond":{"$eq":["$$this.month",12]}
}
},
"cond":{"$eq":["$$this.day",1]
}
}},
0]
}
}}
])
Updated Mongoose code:
Emp.aggregate([
{"$match":{"_id":mongoose.Types.ObjectId(employeeid)}},
"cond":{"$eq":["$$this.month",monthParam]}
}
},
"cond":{"$eq":["$$this.day",dayParam]
}
}},
0]
}
}}
])
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The melting process of Pd-Ni alloy nanobelts with different Ni atom content has been simulated by molecular dynamic (MD) method. The radial distribution function, the Lindemann index, and pair analysis method were used to characterize Pd-Ni nanobelt models in simulation. The results indicate that the melting temperature of Pd-Ni nanobelt with composition far from pure metal was lower than that of other models, and the breaking point of the nanobelt can be illustrated by the Lindemann index. Pair analysis indicates that the number of FCC pairs will decrease and almost disappear at melting point with increasing temperature. The melting points of Pd-Ni alloy nanobelts were also calculated by thermodynamic method, and the results were close to that obtained by MD simulation.
1. Introduction
After carbon nanotube has been reported in 1991 , one-dimensional (1D) materials have received much attention due to their excellent physical property and have been expected to be used in a wide range of application fields [2–6]. Because of their dramatically different behavior from bulk materials, much research work has been done for the structure and properties of nanowires [7–10]. Thermal stability and melting behavior of nanomaterial are another subject that has been studied theoretically and experimentally for a rather long time. The melting process of nanomaterial determined by experiment is very difficult. Nevertheless, computer simulations provide an excellent method to study these melting processes at an atomic level. Up to date, the melting process and thermal properties of many kinds of 1D metal nanomaterial, including Au , ZnSe , GaN , Zr , Ag , Cu , Ni [16, 17], Pd , and Cu3Au nanowires, have been investigated by molecular dynamic (MD) or other computer calculation methods. However, few efforts have been focused on the thermal stability and melting behavior of the 1D binary alloy nanomaterial with different component.
Pd-Ni alloy can be used as catalyst in many reactions [20, 21] and hydrogen sensors . However, its catalytic properties and performance of sensor relate to Pd or Ni concentration in the Pd-Ni alloy. Therefore, the structural stability and melting characteristics of Pd-Ni 1D alloy with different nickel concentration are studied by MD in the present work. And the relationship of melting points and fusion enthalpy of 1D Pd-Ni alloy models for MD process has also been investigated by using the model introduced in the literature .
2. Method of Simulation
The parallel code lrge-scale atomic/molecular massively parallel simulator (LAMMPS) was used for all MD simulations. And visualization of MD simulation was performed using visual molecular dynamics (VMD) and open visualization tool (Ovito) . The embedded-atom method (EAM), a set of -body potentials have been proved that it can accurately describe various dynamic properties of transition and noble metals. The interactions of atoms were modeled using the EAM potential, which is a convenient model to study metal clusters with FCC structure because the local density effects are included in its parameterization. In this work, the EAM potential data was obtained from the literature .
The geometry of nanowire is constructed as a regular FCC lattice with initial surface orientations of , , and in the , , and directions of simulation box, respectively. An infinitely long nickel nanowire is modeled by applying periodic boundary conditions in the direction. The other two Cartesian directions are also simulated with periodic boundary conditions, and the lengths of , directions in the simulation box were large enough to prevent interaction between nanobelt models.
The initial configuration of nanobelt model with the size of shown in Figure 1 has 2000 atoms, where the is the lattice parameter of crystal. In the present study, the Pd-Ni alloy nanobelt models were considered as the ideal solution, so the of Pd-Ni alloy nanobelt can be calculated from the lattice constant of nickel ( 0.352 nm) and palladium ( 0.389 nm) by using the expression of , where was the atomic concentration of nickel in the nanobelt model.
As the ideal binary mixture, positions of Ni and Pd atoms can exchange randomly. Through replacing the Pd atoms with Ni atoms randomly, the models with different Ni concentration can be made, and the content of Ni in the Pd-Ni alloy nanobelt was shown in Table 1. And the integer random distribution number (RNDi) was generated by
In order to remove the interactions which might lead to local structural distortion and result in the unstable simulation, energy minimization of the structure has been performed before starting molecular dynamics simulation. The MD simulations were carried out in the canonical ensemble with a constant number of atoms and volume . The equations of motion were integrated using the Verlet leapfrog algorithm with a time step of 5 × 10−4 ps. The nanobelt was heated to 1800 K in increments of 50 K, and the heating rate was 0.5 K/ps. Near the melting point (in the region of 900–1300 K), the temperature increments were reduced to 20 K to account for the large temperature fluctuations. At each temperature 105 MD trajectory steps were propagated, which is sufficient to ensure the validity of the results presented here.
The radial distribution function (RDF) shown in (2), being regarded as one of the most important parameters, is used to describe the structure characterization of solid, amorphous, and liquid states . Consider where is the probability of finding an atom in a distance ranging from to ( is the step of calculation); is the simulated volume of unit cell; is the number of atoms in the system; and is the averaged number of atoms around the th atom in the sphere shell ranging from to .
The Lindemann index was recently applied to characterize nanoparticles, and it was proposed that melting of a nanoparticle at a critical value in the range of 0.03–0.05 . The Lindemann indices of each atom in the models were calculated at each temperature as where and are the Lindemann indices of the th atom and the whole model, respectively; in (3) denotes the thermal average at temperature ; is the distance between the th and th atoms.
Pair analysis (PA) technique, which can effectively describe the characteristics of the geometric structural evolvement, has been used for analysing the geometric features of the atomic cluster . In the present study, PA method was used to analyse the structural changes accompanying the melting process of Pd-Ni 1D models. Based on the regulation of bond pair, if two atoms are within a specified cutoff distance, they are called a bonded pair of models [29, 30]. In RDF curves, is the first minimum value; then was defined as cutoff distance for PA. The four-index number is used to express bonded pairs of atomic clusters [29, 30]. If any atomic pair A-B formed a bond, and otherwise ; refers to the number of near neighbors which form bonds with both atom A and atom B; stands for the number of pairs among the neighboring atoms forming bonds; is a special distinguished index parameter. Based on the PA technique, the 1201 and 1311 bond pairs represent the rhombus symmetrical features of short-range order. The FCC structure has the type of 1421 bond pairs, whereas the HCP crystal has the equal number of 1421 and 1422 bond pairs. The difference between 1421 and 1422 bond pairs is the topological arrangement of the two bonds between the four neighbors. The bond pair 1551, 1541, and 1431, corresponding to a pentagonal bipyramid, is the characteristic of icosahedral order.
3. Results and Discussion
Figure 2 shows the total energy of nanobelts with different Ni content versus temperature (TE curve) during heating process. Total energies increase linearly with temperature in the early stage. When close to the melting transition temperature, simple jumps in total energy can be easily observed. The melting transition temperature of model can be estimated according to the TE curves. However, being different from that of cluster and bulk system, in the TE curve of nanobelt besides sharp increasing region, there is also a decreasing part after melting takes place. Therefore, the derivative curve of TE versus temperature shown in Figure 2, which can be considered as heat capacity , should have sharp peak and valley region. The melting points of the nanobelts can be determined by the position of the peak because of the heat absorption of melting. For reducing the total energy, especially surface energy, liquid 1D nanomaterial will change to spherical-like material due to the little interaction of atoms in the model at high temperature. That is to say, the nanobelt will break for decreasing the TE after 1D nanomaterial melting. From the derivative curve, the breaking temperature of 1D Pd-Ni can be estimated by the position of the valley. The melting temperature and breaking temperature of all the nanobelt models can be found in Figure 2. There are two sharp increasing and decreasing regions in the TE curve of PdNi1200 model. The reasons of emerging the first increasing and decreasing region were the melting of the model and decreasing of surface energy. In Figure 3(a), part of crystal structure can be found in the model, which results in PdNi1200 model holding 1D nanomaterial. With the temperature increasing, the melting of whole model (Figure 3(b)) and the collapse of nanobelt should induce the second increasing and decreasing region in the derivative curve.
(a)
(b)
Figure 4 shows the temperature dependence upon the Lindemann index of the nanobelts during heating. It is clear from Figure 4 that the Lindemann index increases slowly and linearly with temperature at low temperature stage because of the linear increase in atomic kinetic energy with temperature. The value of the Lindemann index during this stage is very small since most of the atoms do not have large amplitude motion but merely vibrate around their original lattice positions. Following the first stage, the Lindemann index increased and decreased rapidly. It is evident that the melting point and breaking temperature of the nanobelt can be estimated from the derivative curve of the Lindemann index versus temperature. At the temperature corresponding to the peak of derivative curve, lots of atoms in the nanobelt model exhibit large amplitude diffusion, which should be considered as melting of nanobelt. In the curve, there is also a sudden collapse of the 1D structure at the temperature corresponding to the valley. The melting temperature and breaking temperature estimated from derivative curves were the same as those shown in Figure 2. It can be found that with Ni concentration increase in the model, the fusing temperature decreases first and then increases. However, the breaking temperature of nanobelt with different Ni concentration did not obey this rule due to relating with the atom position and diffusion process of models. The Lindemann index of every atom in models can be used to determine the melting point and breaking temperature more precisely. From Figure 5, it can be found that the Lindemann index of atoms in PdNi1600 model was bigger than 0.05 at 1080 K which indicates that melting process occurs at this temperature . At 1200 K, though there was no breaking, the Lindemann index of some atoms was very high, which suggests that the nanobelt will break at little higher temperature.
Structural properties and changes of nanobelt during heating are of interest in understanding mechanical and other properties of materials. Figure 6 shows that there are only 1421, 1311, and 1211 pairs in the 1D Pd-Ni alloy models at very low temperature. It can be found that the number of 1421 pairs will decrease obviously with increasing temperature. Due to the collapse of 1421 pairs, atoms in the FCC structure should form other pairs, which can be identified by the elevation of the 1201, 1301, and 1311 pair numbers. At melting temperature, the number of 1421 and 1311 pairs in the nanobelt drops abruptly due to melting transition of nanobelt, and the 1421 pairs almost disappear after nanobelt melting. It can also be found that the number of 1201 and 1321 bondtypes increased obviously at melting temperature, which was caused by the collapse of 1311 and 1421 pairs.
Through pure element thermodynamic data, the classical thermodynamics method can be used to predict many thermodynamic parameters of bulk alloy, such as enthalpy and melting point. Therefore, by building the relationship of thermodynamic properties of nanomaterial and bulk material, thermodynamic parameters of nanomaterial can also be calculated by thermodynamics method. In this study, the fusion enthalpy of 1D Pd-Ni alloy model was calculated by (5) which was reported by Guisbiers and Buchaillot . Consider where and are the size-dependent melting point and fusion enthalpy, respectively; and are the melting point and fusion enthalpy of bulk material, respectively. Here, value can use the results of MD simulation. Thermodynamic parameters of bulk Pd-Ni alloy can be calculated from the pure Ni and Pd thermodynamic data which has been shown in the Appendix. For example, , , and can be calculated by (6) and (7), respectively. The expression of and , which were Gibbs energy of liquid and solid phases of bulk material, used in (6) and (7) can be illustrated by (8). Then, using the thermodynamic data of bulk material calculated previously, and will be obtained by (5). Consider
All the calculated results have been shown in Table 2. It can be found that the relation between melting point of nanobelt model and Ni concentration is the same as that of bulk phase Pd-Ni alloy. However, because the specific surface area of nanomaterial is very great, the Pd-Ni nanobelt melt temperature is smaller than that of bulk phase. The melting points of nanobelts can be reproduced by equation of . The results shown in Table 2 indicate that the melting point obtained by MD simulation is close to , and the error is below 5%. Particularly, the difference of melt point between MD and thermodynamic method for PdNi800 and PdNi1200 was only 3-4 K. The nanobelt models used in this work were considered as the ideal solution, so the error may be different when the other mix model was used, such as aggregation state model.
4. Conclusion
Summarily, the heating process of Pd-Ni alloy nanobelts has been simulated by MD and the melting temperature was also calculated by thermodynamic method. The melting and breaking of Pd-Ni alloy nanobelts can be indicated by increasing and decreasing regions of total energy relating to temperature curve. With increasing temperature, number of FCC pairs will decrease and almost disappear at melting point. The melting point is lower than bulk phase Pd-Ni alloy, and the melt point obtained by MD is close to that of calculated by thermodynamic method.
Appendix
FCC-Ni
Liquid-Ni
FCC-Pd
Liquid-Pd
Acknowledgments
The authors acknowledge the support of Project supported by the National Natural Science Foundation of China (Grant nos. 51207031, 51177022), the Promotive Research Fund for Excellent Young and Middle-Aged Scientists of Shandong Province (Grant no. BS2011NJ002), China Postdoctoral Science Foundation (Grant no. 2013M541368), the Science Foundation of HIT at Weihai (Grant no. IMJQ10080026), and the Natural Scientific Research Innovation Foundation in HIT (Grant no. IMXK57080026). | https://www.hindawi.com/journals/jnm/2013/486527/ |
Jackson, Matthew O. and Yariv, Leeat (2005) Diffusion on Social Networks. Economie Publique (Public Economics), 16 (1). pp. 3-16. ISSN 1373-8496. https://resolver.caltech.edu/CaltechAUTHORS:20171103-144115558
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Abstract
We analyze a model of diffusion on social networks. Agents are connected according to an undirected graph (the network) and choose one of two actions (e.g., either to adopt a new behavior or technology or not to adopt it). The return to each of the actions depends on how many neighbors an agent has, which actions the agent’s neighbors choose, and some agent-specific cost and benefit parameters. At the outset, a small portion of the population is randomly selected to adopt the behavior. We analyze whether the behavior spreads to a larger portion of the population. We show that there is a threshold where “tipping” occurs: if a large enough initial group is selected then the behavior grows and spreads to a significant portion of the population, while otherwise the behavior collapses so that no one in the population chooses to adopt the behavior. We characterize the tipping threshold and the eventual portion that adopts if the threshold is surpassed. We also show how the threshold and adoption rate depend on the network structure. Applications of the techniques introduced in this paper include marketing, epidemiology, technological transfers, and information transmission, among others. | https://authors.library.caltech.edu/82948/ |
A union of clean, linear geometry and the unpredictable art of hand poured glass, Weave glass finds it's beauty in the meeting of contrasts, creating a unique Zen Modern sensibility. The shimmering colors of Weave glass take their cue from nature, evoking air, earth, and water in muted tones of autumn gold, sea green, ocean blue, and metallic bronze. Each color is finished with an iridescent patina, giving the surface of the glass a visual dimension that shifts endlessly with the play of light and shadow. | https://www.walkerzanger.com/inspiration/style.php?view=Zen |
anana leaves are abundant in Southeast Asia and South America and are used to make fertilizers, prepare food and make baskets, trays and bags. These large leaves are dried and then cut to size before being woven into natural, chemical-free household items. You can make banana leaf baskets by weaving leaf segments together.
Things You'll Need:
- Needle And Thread
- 30 To 50 3-Foot Dried Banana Leaf Strips
Lay six to eight, 2- to 3-inch wide and 3-foot long banana leaf strips parallel to each other on the floor or table. The dried leaves should be approximately even in width and length.
Take another banana leaf strip of similar width and length and place it at a 90-degree angle on the middle of the leaves you have laid out. Weave it through the middle of the six to eight banana leaves using an under-over pattern. Pull the banana leaf so that the two ends are even.
Continue making the base of basket by weaving six to eight banana leaf strips through the first set of leaves. Pull the leaves tight to close up any holes in the weave. You should now have a woven square with loose leaf fronds sticking out of it on all four sides in a cross shape.
Sew the base of the basket with a needle and thread to prevent the banana leaves from moving. Put in one stitch in each leaf along the sides of the woven base. Fold the unwoven side leaves up so that they are standing up around the base of the basket.
Take another banana leaf strip and sew it to a leaf at one corner of the basket. Weave the loose end of the leaf around the basket to the other side or as far as possible. Push the woven leaf down against the bottom edge of the basket to prevent any holes. Secure it by placing a stitch into the leaf with the needle and thread.
Continue weaving leaves until the basket is fully formed. Secure all the leaves by sewing them with the needle and thread.
Tip
You can finish off the top of the basket by sewing a ribbon or fabric trim around the top edge. A tighter weave will require more banana leaves but will make a stronger basket. A banana leaf tray can be made by tightly weaving a large basket base and cutting off the excess leaves on the sides.
Warnings:
- Use banana leaves that have been professionally dried. Moisture in the leave can lead to rotting or mildew. Do not place banana leaf baskets near a heat source as they are flammable.
References
Writer Bio
Nadia Haris is a registered radiation therapist who has been writing about nutrition for more than six years. She is completing her Master of Science in nutrition with a focus on the dietary needs of oncology patients. | https://ourpastimes.com/how-to-make-banana-leaf-baskets-12603165.html |
The Jukon sauna is distinguished by an original and interesting shape, resembling a drop of water in cross-section. The organic appearance of the sauna gently blends it into its surroundings and blends harmoniously with the surrounding vegetation.
The Jukon sauna, despite its small size, is spacious and comfortable inside. The flat floor and slightly sloping walls add to its charm and create a cozy atmosphere, enhancing the sensations during the screening. The interior heats up very quickly, because ThermoWood maintains the temperature perfectly and provides high sound insulation.
The sauna can easily accommodate up to 4 people, and thanks to its small size it will be perfect for a small plot. | https://vingberg.pl/produkt/garden-sauna-jukon/?lang=en |
It is called guard because everybody is supposed to listen/guard the frequency just in case someone has a problem. Guard definitions: a state of caution, vigilance, or preparedness against adverse circumstances. watch over in order to protect or control.
Why is aircraft emergency called guard?
What is the frequency supposed to be used for? 121.5 MHz is a guarded frequency, hence the “Guard” comment you constantly hear. 121.5 MHz, and UHF 243.0 MHz for military operations, are monitored by ATC and others, including maritime agencies.
What does guard mean in aviation?
The aircraft emergency frequency (also known as GUARD) is a frequency used on the aircraft band reserved for emergency communications for aircraft in distress.
What does radio Guard mean?
A ship, aircraft, or radio station designated to listen for and record transmissions and to handle traffic on a designated frequency for a certain unit or units. Dictionary of Military and Associated Terms.
What is the 121.5 frequency?
International Distress/Emergency Frequencies
121.5 MHz: International Aeronautical Emergency Frequency. 156.8 MHz: International Maritime Distress, Calling and Safety Frequency. 243.0 MHz: NATO Combined Distress and Emergency Frequency.
What do pilots say in an emergency?
Pilots believing themselves to be facing an emergency situation should declare an emergency as soon as possible and cancel it later if the situation allows. The correct method of communicating this information to ATC is by using the prefix “MAYDAY, MAYDAY, MAYDAY” or “PAN PAN, PAN PAN, PAN PAN” as appropriate.
Is 121.5 still monitored?
DOES ANYONE STILL MONITOR 121.5 MHZ ELTS? Even though satellites no longer monitor 121.5 MHz signals, the search and rescue community will still respond when notified through other means. ELTs were originally intended to use 121.5 MHz to inform air traffic control and pilots monitoring the frequency of an emergency.
What does to be on guard mean?
Definition of on guard against
: alert and ready to respond to possible danger, threats, problems, etc. We need to be on guard against attack.
What happens if you squawk 7500?
The transponder sends the four-digit squawk code and aircraft altitude to air traffic control. The code should always be 1200, unless another code is assigned by ATC. However, if there is an emergency squawk 7500 for hijack, 7600 for communication failure, or 7700 for emergency.
What does squawk 7000 mean?
7000. ICAO. VFR standard squawk code when no other code has been assigned. US.
What frequency does an ELT transmit on?
ELTs of various types were developed as a means of locating downed aircraft. These electronic, battery operated transmitters operate on one of three frequencies. These operating frequencies are 121.5 MHz, 243.0 MHz, and the newer 406 MHz. ELTs operating on 121.5 MHz and 243.0 MHz are analog devices.
What are the two frequencies that commonly used for distress urgency and safety?
The frequency band 406-406.1 MHz is used exclusively by satellite EPIRBs (emergency position indicating radio beacons) in the Earth-to-space direction. The frequencies 161.975 MHz (VHF-CH AIS 1) and 162.025 MHz (VHF-CH AIS 2) are used for AIS search and rescue transmitters (AIS-SART) in search and rescue operations.
Who controls communications when you are in distress?
6.6 Control of Distress Traffic
The control of distress traffic is the responsibility of the aircraft in distress or of the station which relays the distress message.
What do squawk codes mean?
SQUAWK codes are four digits and they are used to easily identify a specific aircraft when detected on a radar, or to determine what an aircraft needs in the case of an emergency or situation in which a flight plan needs to be changed.
What frequency would you use in the event of an emergency?
Although the frequency in use or other frequencies assigned by ATC are preferable, the following emergency frequencies can be used for distress or urgency communications, if necessary or desirable: 121.5 MHz and 243.0 MHz. Both have a range generally limited to line of sight.
Does ATC monitor guard?
Most ATC Facilities monitor 121.5MHz and can provide help for you on guard. You can use guard if you loose contact with ATC and ask for a new frequency or you might actually even hear the controlled looking for you on guard. | https://sh3llc0d3r.com/in-real-life/your-question-why-is-121-5-called-guard.html |
While many sporting events have been put on pause due to COVID-19 precautions, AJ Werner has proven his resolve of as a true athlete by not letting the external forces inhibit his dedication to his craft – basketball.
Werner is a Pierce College freshman coming into the men’s basketball team with the proper drive and discipline that will better enhance his skills on the court. He has been able to stay busy and fit at the comfort of his own home.
“Everything I’ve done has been from home,” Werner said. “I run three miles through hills around my neighborhood to keep my legs strong and to stay conditioned. I have some dumbbells in a room that I use. I also do bodyweight exercises. I’m able to get shots up on a hoop and work on dribbling on my driveway.”
Werner is still able to mix up his personal training with team drills over Zoom. The online training sessions allow for team synergy and coach criticism and input.
“I practice six days a week. Twice a week with the team over Zoom for three hours,” Werner said. “On my own I don’t really time how long I practice. I usually don’t stop practicing until I make a certain number of shots.”
Head coach Charles White has been leading the charge for this year’s men’s basketball team. He says that the transition to online training has been challenging but he still finds a way to help develop their skills.
“They finish up training with me. Right now, we’re working on defensive fundamentals and they seem to be buying in as much as possible on Zoom,” White said. “We’ve also been watching a lot of film of prior games from last year.”
White feels that he has a solid and strong team this year and that Werner is a prime example of an athlete that he can trust.
“He’s a real good kid,” White said. “The reason why he got nominated for Athlete of the Week is because he shows up. He’s been showing up since the fall and probably only missed one time because he had to go to the dentist. He’s a guy I can trust. I put a ball in his hands and I know he’s gonna do what needs to be done with it.”
Werner’s father, Jay Werner, has also coached basketball at LA Valley College, Glendale, and the Poly Boys varsity team. He expressed pride about his son receiving the Athlete of the Week award.
“To be honest, it feels good,” Jay Werner said. “Joining the Pierce College team and embracing the program that they have put together has in my eyes really changed his game, since I have watched him workout daily. I’ve seen the hard work he’s put in, and to be rewarded for that hard work from his coaches is cool.”
Jay Werner also expressed the admiration he has for his son to be committed to getting better even through the pandemic.
“He used this incredibly tough and crazy time to dedicate himself to the game that he now truly loves,” Jay Werner explained. “It can only lead to a successful future in life in whatever he chooses to do.”
AJ Werner is anxious to continue his basketball career and has his goals set high with the full intention of working to achieve them.
“I’ve been given a great opportunity to come here to Pierce and play,” AJ Werner said. “I know that with the help of my coaches and teammates I’ll be able to have a successful season and then hopefully transfer to a four-year school to continue my basketball career.”
For now, much of the training and sporting events will still be put on pause or held with unconventional circumstances until circumstances improve but AJ Werner has displayed how a true athlete will refuse to become lazy and will find ways to still get work done despite the obstacles that stand in their way. | https://theroundupnews.com/2021/05/16/athlete-of-the-week-covid-19-edition/ |
CSUN Professor Offers a Caution About Isolation Associated with Telecommuting
As the global COVID-19 pandemic continues, the number of people who are working from home continues to grow.
Although experiences vary, many telecommuters enjoy increased autonomy, schedule flexibility, and a decrease in travel time, traffic issues and gas expenses. But California State University, Northridge marketing professor Qin Sun who teaches in the David Nazarian College of Business and Economics, cautioned that telecommuting can have some downsides.
“Telecommuters may feel lonely and disconnected from their peers and organizations,” Sun said. “They may also lack the influential network connections and acknowledgment of their contributions needed for career advancement.”
Sun said telecommuting can be associated with physical and psychological isolation. She co-authored a paper on that very subject, ‘Employee Isolation and Telecommuter Organizational Commitment,’ that appeared in the latest issue of the Employee Relations journal. Her co-authors were Wendy Wang, Department Chair of Trident University’s Information Management Technology and Computer Science programs and Leslie Albert, associate professor of Management Information Systems at San Jose State University.
Other negative effects of telecommuting include experiencing an increased workload and expectation to be constantly available to “make up” for their absence in the office. Many telecommuters also struggle to keep their work and personal lives separate.
“Informal and serendipitous interactions through technological tools such as video teleconferencing, phone and email should be encouraged to reduce potential “side effects” of working at home such as the psychological isolation,” Sun said. “Given the widespread availability of rich, synchronous communication media, it is possible that workers can overcome physical and psychological isolation through technologies.”
Novice telecommuters may also feel pressured to learn new technologies to keep up with work and family. Sun said that some may have the “out of sight, out mind” mentality, where they believe their lack of visibility means their chance of potential work opportunities will be reduced.
She advised that telecommuters should strive for balanced, nutritious meals and find time for a daily workout during their work time, such as 10-minute meditation or yoga, to help energize and rejuvenate their bodies, and reduce the stress of working at home.
“When virtual meetings or informal gatherings are offered, it is worthwhile to attend and stay in touch with colleagues, supervisors and the organization,” she said. “It is important for new telecommuters to create a work routine for themselves, keep themselves in a good mental state, and stay positive.”
Sun encouraged organizations to use teleconferencing and other communication media that closely mimic face-to-face interactions with advanced internet communication technologies (ICTs) such as Zoom, Google Meet and Skype. She said virtual happy hours, other social gatherings and “water-cooler chats” can encourage ongoing interactions.
She advised direct managers to strive to keep lines of communication open so employees don’t feel forgotten. Check-in messages can encourage employees with telecommuting struggles to share their needs and concerns, Sun said.
Working from home over a long time due to the pandemic could require many employees to shift to new work habits that support telecommuting, such as acquiring better technology and equipment, and establishing routines and systems that keep work and personal lives separate. | https://csunshinetoday.csun.edu/education/csun-professor-offers-a-caution-about-isolation-associated-with-telecommuting/ |
Gypsy's cabbies recall unremarkable fare — but, in hindsight...
Driving a taxi on the overnight shift for the past 15 years, John Harmon has seen plenty of odd characters slip into the back of his cab.
Harmon has seen rowdy college students and even picked up a man who had just committed a bank robbery. But what Harmon experienced last week stands out — even if it didn't cause any suspicion at the time.
When Harmon was dispatched last week to a home just north of Springfield, he had no idea that a slain woman was likely lying on a bed inside the house and the people accused of killing her had just sat down in his back seat.
After stowing their luggage, the pair calmly asked for a ride to the nearby Days Inn hotel on Glenstone Avenue just north of I-44.
Harmon put the cab in gear and left the home on North Volunteer Way as the passengers talked quietly. They arrived at the hotel, and the woman paid with cash before the couple calmly entered the hotel.
No blood. No weapons. Nothing out of the ordinary.
"I didn't think anything about it," Harmon said. "It was just a normal pick-up for me."
It wasn't until a few days later that Harmon believed he saw the faces of the same people who were in his cab that morning — Gypsy Blancharde and her boyfriend 26-year-old Nicholas Godejohn — had been charged with first-degree murder in the stabbing death of Gypsy's mother, 48-year-old Clauddinnea "Dee Dee" Blancharde.
Harmon said he doesn't normally watch the news, but he has been drawn in by this bizarre case.
Friends and neighbors believed that Gypsy was disabled and needed a wheelchair. They feared Gypsy might have been abducted when Dee Dee's body was discovered by authorities on Sunday.
Gypsy can, however, walk just fine, and authorities believe she instructed Godejohn to stab Dee Dee to death before the couple fled to Wisconsin. Furthermore, Greene County Sheriff Jim Arnott said Tuesday that Dee Dee and Gypsy have long been running a financial fraud scheme, obtaining donations from friends and strangers under false pretenses.
The Yellow Cab company says the couple apparently relied on Yellow Cab taxis for transportation around Springfield after Dee Dee's death and before they left for Wisconsin. Information provided by the cab company helps provide a timeline for the couple before Monday's arrest.
Harmon said it has been shocking to follow the story over the last couple of days, but having two people accused of murder in the back of his cab doesn't make him want to change professions.
"Doing this job, you never know what you're going to get," Harmon said. "We haul hookers, we haul crackheads, we haul drunks, all different kinds. If you're going to be afraid of the job, don't do it."
Cab driver Janice Buttram was driving the taxi when people she believes to be Gypsy and Godejohn requested a ride from the Greyhound station on Kearney Street back to the Days Inn on Thursday afternoon.
Buttram said she always tries to engage her riders in conversation, and the talks she had with the people she believes were Gypsy and Godejohn left her feeling uneasy.
Buttram said Gypsy claimed to be 14 years old and said that Godejohn was her brother, but she said the couple was sitting too close together to be brother and sister.
Buttram said both Gypsy and Godejohn seemed "slow." Buttram said Gypsy spoke in a "high-pitched," "squeaky" voice and was wearing a big black wig.
Buttram got the impression Gypsy was giving the orders.
"She paid, she was in control," Buttram said. "She was not scared of him in any way."
Buttram said she never felt threatened during the encounter, but it has been fascinating to follow the story and strange to be a part of it.
She said she thought about reporting the people she believes were Gypsy and Godejohn to police after dropping them off, but she said she can't report every strange thing she sees doing her job.
Buttram, who was a singer and entertainer before she started driving the cab, said what has stuck with her the most about the encounter with the couple is Gypsy's name.
Buttram told Gypsy that she was a big fan of "Gypsy," the movie about burlesque entertainer Gypsy Rose Lee, whose mother used her to make money.
The woman believed to be Gypsy Blancharde told the cab driver that Gypsy Rose Lee is her namesake.
Here is the couple's activity, according to a cab company representative:
•A cab picked up Gypsy and Godejohn from the house on the 2100 block of North Volunteer Way on Wednesday at 5:48 a.m. and dropped them off at the Days Inn on 3114 N. Kentwood Ave.
•A cab picked up Gypsy and Godejohn from the Greyhound station on Kearney Street on Thursday at about 1:30 p.m. and took them to the Days Inn on North Kentwood Avenue. The cab driver on that trip said that the couple had just purchased tickets for a bus ride to Wisconsin later in the week.
•A cab picked up Gypsy and Godejohn from the Days Inn on Friday at 6:40 a.m. and took them to the Walmart on Glenstone Avenue and Kearney Street.
•Gypsy and Godejohn shopped at Walmart for 10 minutes. A cab then took the couple from Walmart to the Greyhound station on Kearney Street. | https://www.news-leader.com/story/news/crime/2015/06/17/gypsys-cabbies-recall-unremarkable-fare-hindsight/28883119/ |
- Personality is a psychological and behavioural attribute, habits, traits, attitudes which differ from person to person, and are visible externally through roles and statues and internally through motivation, goals, and other features of selfdom.
- The term ‘personality’ is extracted from the Latin word ‘persona’ which means the social mask that people wear to play character imposed by societal conventions and traditions.
- It is the sum total of a person's behaviour, and traits including habits, thinking, attitude, choices and philosophy of life.
- It is a combination of ways in which people retaliate and interact with others.
- Personality trait or characteristic is influenced by two factors
- Inherited traits (which are acquired by parents or family) such as physical features.
- Learned traits (acquired by observing, practising and repeating surrounding) such as perception, value and attitudes.
2. Attributes of Personality
- Locus of control
- It believes the behaviour of any individual is controlled by his/her code of conduct.
- Code of conduct has a direct impact on results and consequences.
- Categories of locus of control:
- Machiavellianism
- The tendency to manipulate the situation to win and they are great persuaders.
- They are the people who are more practical, have fewer emotions, and assume any means is justified to attain ends
- Self-esteem
- It is the major factor to determine and judge an individual's success or failure.
- It is a self-concept through which people tend to like or dislike themselves.
- Extroversion and introversion
- Individual's personality is categorised in two on the basis of the scale of interaction with the environment.
- Type A and Type B Behaviors
- Identified by Meyer Friedman and Ray Rosenman
3. Personality Theories
a) Trait theory
- Proposed by Allport and Cattell, this theory assumes that certain attributes and characteristics comprise individuals personality. On the basis of behavioural tests, Allport divided two categories of traits:
- Common traits- Allport identified a distinction between individual traits and common traits which are used to compare people. He established six different common traits in individuals: Economical, Political, Theoretical, Aesthetic, Religious and Social.
- Personal Disposition- Each individual has its own unique identity and traits called as personal disposition, divided into three categories: Cardinal, Central and Secondary disposition.
- Cattell developed sixteen factors of human personality traits: abstractedness, emotional stability, warmth, apprehension, intelligence, liveliness, openness to change, perfectionism, privateness, rule consciousness, tension, sensitivity, social boldness, self-reliance, vigilance, and dominance.
- Big Five personality traits, also referred to as the OCEAN model, are a suggested grouping for personality traits. The acronym OCEAN stands for: Openness to experience, Conscientiousness, Extraversion, Agreeableness, and Neuroticism
b) Sigmund Freud’s Psychoanalytic Theory
- According to this theory, a person is encouraged and motivated by unforeseen forces rather than rational thoughts. Freud explained three attributes of the theory:
- Id- It is the intrinsic element of personality, it is the unconscious part of the mind which requires instant satisfaction of biological needs likes hunger, sex, thirst etc.
- The ego- It is a conscious part of an individual's personality which deals with the external world. It directs postponed satisfaction, unlike Id.
- Super Ego − It includes the traditional values of a society that guides our behaviour ethically. It helps to analyze the difference between right and wrong.
c) Erikson’s Psychological Theory
- This theory states that individuals and society are interlinked. Environment and social factors play a primary role in shaping personality.
- Erikson presented eight stages of personality development, completion of which leads to a groomed and healthy personality. These eight stages are:
- Infant
- Early childhood
- Young and middle adulthood
- Mature adulthood
- Adolescence
- Oral sensory stage
- Muscular and anal stage
- Locomotor genital stage
d) Immaturity and maturity continuum
- Proposed by Argyris, this theory says that personality develops with continuity of immaturity to maturity.
- On the basis of the degree of personality development, he explained seven changes in personality from infant to adult.
Child Adult
- Stage of passivity ------ to------ Stage of activity
- Stage of dependence ------ to------ Stage of independence
- Stage of predictable behaviour ------to---- Stage of unpredictable behaviour
- Stage of less interest ------ to------ Stage of several interest
- Stage of short term perspective ------ to-----Stage of the long term perspective
- Stage of subordinate position ------ to------ Stage of superior position
- Stage of lack of self-concept ------to-----Stage of self-image and self-esteem
e) Personality development theory by Freud
- This theory is established on the grounds of satisfaction of sexual intuition.
- Progress in personality is a consequence of sources of stress, which affects an individual on five different stages of development:
- Oral stage (Birth to 18 months of age)
- Anal stage (18 months to 3 years)
- Phallic stage (3 years to 7 years)
- Latency stage (7 years to 12 years)
- Genital stage (12 years to 20 years)
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