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Most Common Types of Soil Found in Carpet
Our primary function as a cleaning service is identifying and removing soils in an effective and efficient manner. The more we know about dirt/soil the more successfully we can deal with it. Soil is a destructive force. Unless it is removed promptly, soil will discolor and eventually destroy any carpet.
As previously stated, the key job of carpet cleaning is to remove soil from carpet. However, there are several different types of soils and contaminants found in carpets. Knowing what type of soil is in the carpet is frequently the first step in effectively removing it.
As much as 80% of these soils are actually deposited onto carpets from the shoe bottoms of people walking into facilities, according to Mark Baxter, a carpet cleaning expert and product manager for U.S. Products…
U.S. Products' Carpet Cleaning Advisory found the top 10 types of soils found in carpets:
1. Sand, clay, and other "gritty" materials
2. Natural fibers such as lint from clothing
3. Gum
4. Petroleum, oil, and grease
5. Human hair and skin
6. Dust mites, fleas, and other insects
7. Organic soils and materials (minerals and soils from landscaping areas, for example)
8. Airborne carbon and automotive exhaust
9. Spilled food or beverages
10. So-called "miscellaneous unknowns"
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text:
Part of Speech: Noun
Meaning: 1. The metaphorical technique of naming a specific part when referring to the whole. 2. Naming the whole to indicate a part.
Notes: Today's Good Word is the proper literary term for a habit that is ubiquitous in common speech. The adjective for it is synecdochic(al) and you may use the adverb when you speak synecdochically. The practice of using synecdoches is synecdochism.
In Play: You avail yourself of synecdoche every time you say a neighbor lives two doors down the street, meaning houses. When your teenaged son whose English grades are low says, "I can't go out tonight, the'rents have the wheels," he is saying "car" with one of the major rhetorical devices of English. The reverse situation, using a whole to refer to a part, is also synecdoche: "I think Ghana is going to beat Brazil in the World Cup," besides being wishful thinking, is a synecdoche in which wholes (Ghana, Brazil) refer to only parts of themselves (the Ghanaian and Brazilian soccer teams).
Word History: Today's Good Word was taken whole from Greek synekdoche, the noun of the verb syn-ek-dechesthai "to take a part of". This verb comprises a prefix syn- "with, together" + a stem ek "out of" + dechomai "to take, receive." Ekdechomai alone means "take" in the sense of "understand", the opposite of the meaning of mistake. The doche is cousin to Latin doc-ere "to teach", found in English words such as doctor and dogma. (Saying 'Thank you' to Katy Brezger for suggesting today's Good Word in the Agora is almost synecdoche, since it expresses only a part of our gratitude.)
Come visit our website at for more Good Words and other language resources!

source: HuggingFaceFW/fineweb-edu


Simulink Design Optimization
Magnetic Levitation Controller Tuning
This example shows how to use numerical optimization to tuning the controller parameters of a nonlinear system. In this example, we model a CE 152 Magnetic Levitation system where the controller is used to position a freely levitating ball in a magnetic field. The control structure for this model is fixed and the required controller performance can be specified in terms of an idealized time response.
Earnshaw's Theorem
Earnshaw's theorem proved that it is not possible to achieve stable levitation using static, macroscopic, classical electromagnetic fields. However the CE 152 system works around this by creating a potential well around the point at which the ball is to be suspended, thereby creating a non-inverse square law force. This is achieved by an inductive coil that generates a time varying electromagnetic field. The electromagnetic field is controlled through the use of feedback to keep the ball at the required location.
Model Description
The magnetic levitation system is a nonlinear dynamic system with one input and one output. Double-click the Magnetic Levitation Plant Model to open this subsystem. The input voltage is applied to a coil that creates the electromagnetic field. The output voltage is measured by an IR receiver and represents the position of the ball in the magnetic field. The diagram below outlines this system.
The physical system consists of a ball (with mass 0.00837 kg) which is under the influence of three forces:
 - The magnetic field produced by an inductive coil. This is modeled by the Power amplifier and coil block in the Simulink® model. The input to the inductor is a voltage signal and the output a current. The force from the coil depends on the square of the current, the air-gap between the coil and the ball, and the physical properties of the ball. This produces an upward acting force on the ball.
 - The gravitational force acting downwards
 - A damping force which acts in a direction opposite to the velocity at any instant of time
These three forces cause the resulting motion of the ball and are modeled in Simulink as shown.
open_system('maglev_demo/Magnetic Levitation Plant Model')
Non-linearities arising from saturation of the coil and changes in dynamics outside the limits of the magnetic field are also modeled in the Simulink Model. As the force from the coil decays according to an inverse square law larger voltages are required the further the ball is from the coil. The control signal is scaled to account for this and the scaling is included in the Control signal scaling blocks.
Control Problem Description
The requirement for the controller is that it be able to position the ball at any arbitrary location in the magnetic field and that it move the ball from one position to another. These requirements are captured by placing step response bounds on the position measurement. Specifically we require the following constraints on the ball:
 - Position constraint: within 20% of the desired position in less than 0.5 second
 - Settling Time Constraint: within 2% of the desired position within 1.5 second
To meet the control requirements we implement a Proportional-Integral-Derivative (PID) controller. For convenience the controller uses a normalized position measurement with a range from 0 to 1, representing the bottom-most and top-most positions of the ball respectively.
Simulink® Design Optimization™ and numerical optimization is ideally suited to tune the PID coefficients because:
 - The system dynamics are complex enough to require effort and time for analysis if we approach the problem using conventional control design techniques.
 - The controller structure is fixed
 - We have knowledge of the step response we require from the system.
Setting Constraint Values
Given the step response characteristic we desire, it is simple to specify the upper and lower bounds of the response. Double-click the Position Constraint block in the Magnetic Levitation Plant Model subsystem to view constraints on the position of the ball. The constraint lines may be moved using the mouse.
You can launch a pre-configured optimization task in SDOTOOL by first opening the model and by double-clicking on the orange block at the bottom of the model. From the SDOTOOL, press the Plot Current Response button to simulate the model and show how well the initial design satisfies the design requirements.
Defining Tuned Parameters
We select the PID controller parameters to tune by opening the Design Variables editor, as shown below
Running the Optimization
After specifying the optimization parameters and the required step response bounds we start the optimization by pressing the Optimize button from the SDOTOOL. During optimization, the plots are updated with the position of the ball for each iteration and the dark curve shows the final optimized trajectory of the ball (as shown below).
Verifying the Results
Once we complete the optimization, it is important to validate the results against other step sizes. A successful parameter optimization should be able to provide good control for all steps sizes close to the tuned step size of 1. Step sizes from.7 to 1 should be tested to confirm the controller's performance. The following plot shows the response to a step input from 0 to 0.85 at 0.1 seconds.
The verification step shows that controller's performance satisfies the requirements specified and the tuned parameter values are suitable for control. The tuned parameters could be used to provide baseline performance against which other control schemes can be compared, or a baseline for controllers for different operating regions.
% Close the model


Grammar Lesson of the Day: because
Grammar Lesson of the Day: because.
Some years ago I began to notice that my college freshmen had all gotten a very strange idea. They had been taught that one must never begin a sentence with the word because. I have no idea where high school teachers came up with this one. It is like alligators in the Manhattan sewers, or aliens landing in Roswell. Some kook huddled in a condemned building says it, and all at once everybody "knows" it, though it is not in the slightest bit true.
There's nothing special about the word because. It's a subordinating conjunction, like a hundred others. Any of them may begin a sentence – so long as it's a sentence they are beginning. A sentence, whether it begins with because or if or since or although or whenever or while or whatever or whatever, requires a main clause. This is not a sentence:
Because I could not stop for death.
But it's because it lacks a main clause. Let Emily Dickinson supply one:
The "rule" that the teachers have promulgated, besides being in itself utterly absurd, reveals something about all the other grammatical rules and "rules" that our students learn (or "learn"). That is, since grammar is no longer taught systematically, as a coherent discipline that makes sense of how we make sense, it disintegrates into a set of arbitrary directives, some of them incorrect at that, each separate from the other, without rhyme or reason. It is why I say that, unless they've studied Latin or German, none of my college freshmen has been taught grammar.
In any case, why would you want to begin with because? Well, you might want to emphasize the main clause, leaving it to the end, if that contains the idea you are going to develop. That's what Emily Dickinson wanted to do; she wanted to focus on Death's stopping by to give her a ride. But maybe you want to emphasize the material in the subordinate clause. Then you will probably place it after the main clause:
We're off to see the Wizard,
The wonderful Wizard of Oz!
We hear he is a whiz of a wiz
If ever a wiz there was!
If ever if ever a wiz there was
The Wizard of Oz is one because
Because because because because because –
Because of the wonderful things he does!
We're off to see the Wizard,
The wonderful Wizard of Oz!
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 - Jamie
 Could this be a lack of trust on the part of the professors? I was once told by a pediatrician (no longer our pediatrician) not to kiss my baby's face. As if I could stop. I'm sure she meant "please don't kiss your baby's face if you have pneumonia, or if you have crumbs in your mustache, or if you have just inhaled cigarette smoke." But she can't trust a non-professional bumbling mother or father to understand all the exceptions, so to be safe, she just laid down the law for all time. I imagine that professors find it easier to say "don't start a sentence with because, alright?" than to explain what a sentence fragment is.
 - Tony
 I don't think so, Jamie. It isn't professors who gave out that advice, but schoolteachers. I think they do not know what they are talking about. It's just flat ignorance.
 - Nancy de Flon
 Tony, part of the problem is that not only has none of your freshmen been taught grammar, but also, if you consider the age of many high school and elementary school teachers, they have probably not taught grammar either. We have a situation parallel to that in the Church in which religious ed is being taught to kids by uncatechized catechists. We are hurtling toward a cultural Dark Age.
 - Victor Gallerano
 It seems to me that there is less here than meets the eye: Our fourth graders are taught that they should not begin a sentence with because because they are just coming to terms with simple sentences. Subordination of clauses is too abstract to make sense at that level. In 6th and 7th grade, we correct that notion. "We are moving on, class, now you are able to understand why and how to use a subordinate clause (whether begun by because or some other subordinate conjunction). In the late 7th and 8th grades we teach the various rhetorical values of the syntactical choices one makes in writing.
 I can't speak for "all" your freshmen (really???) but, perhaps some of them weren't listening in the 6th grade when we corrected the because rule. (Has their listening gotten any better, by the way?)
 At any rate, this level of grammar is appropriate to grammar, not high school. The only time grammar is taught "systematically" in high school is during 9th grade when they are trying to re-mediate any gaps or weaknesses in the new freshmen. Needless to say, 9th grade goes to the low-man on the teaching totem pole…and usually the one with gaps and weaknesses of his or her own.
 - _URL_ Manny
 "why would you want to begin with because? Well, you might want to emphasize the main clause"
 Actually it emphasizes both clauses becuase it inverts the normal sequence. It gives the entire sentence a charge. If anything the first half of the Dickenson line is what's memorable to me, "Because i could not stop for death…" If she had gone with the normal sequence niether halves would be memorable.
 - _URL_ F.R. Duplantier
 Why am I responding to this article? Because I want to. And that's a perfectly grammatical, if elliptical sentence. The rules of grammar are intended for people who have no idea what they're doing, to help them make a better impression and avoid embarrassing themselves too much. They're like paint-by-number canvases or Arthur Murray dance lessons. No one who's any good at anything pores over rule books.


text:
PROSHAR Gender Impact Assessment
This study examines the Program for Strengthening Household Access to Resources (PROSHAR)'s impact on gender issues in southwestern Bangladesh. PROSHAR improves livelihoods (Strategic Objective (SO) 1); builds local knowledge of and access to health and nutrition services (SO2); and strengthens people's capacities to respond to chronic disasters such as cyclones, drought, or flooding (SO3).
PROSHAR has integrated gender considerations throughout each of these SOs to ensure that men and women have equal opportunities to participate in and benefit from project activities. This gender impact assessment examines how PROSHAR's gender integration efforts have affected men and women's time allocation, mobility, and decision making. It also studies the most significant changes that occurred because of PROSHAR's work with gender issues.

source: openbmb/Ultra-FineWeb


text:
A hospital advertising campaign can be effective for several reasons. It can improve patient satisfaction and decrease readmission rates. It can also improve the perception of quality. In this article, we'll explore three major benefits of hospital advertisements. But how does advertising affect patients? How can you measure the impact of a hospital's new advertising campaign? Read on to find out! Here are some tips. Read on to maximize your hospital's marketing efforts. And don't forget to measure your results!
Impact of advertising on readmissions
The Impact of Hospital Advertising on Readmissions: A Study of California Medical Centers
A study of hospital readmission rates showed that hospitals that did not advertise had better average performance. This was true of CAHPS 5-star ratings and overall 5-star ratings. The study also found that hospitals with the highest levels of advertising had lower mortality rates and lower average readmission rates than nonadvertising hospitals. It also found a positive impact of hospital advertising on readmissions, particularly in the area of patient communication and education.
A study of acute care hospitals found that almost half of the institutions advertised their services. Hospitals with the highest levels of advertising had higher net assets and higher occupancy rates than hospitals that did not advertise. Hospitals with higher levels of advertising were also more likely to be major teaching hospitals. However, the results were not significantly different for hospitals without large advertising budgets. However, it's important to note that the study only included hospitals that were publicly-reported.
A hospital's readmission rate is directly related to the amount of advertising it spends on its website. The study also examined the number of Medicare patients it admitted. The hospital with the lowest percentage of low-income patients experienced a higher readmission rate than hospitals with the highest proportion. Hospitals in the middle quartile experienced a decrease of 1.7 percentage points and readmissions among the lowest-income patients fell by 2.0 percentage points.
Research has also indicated that patients with more serious conditions have a higher risk of being readmitted. Some of these reasons include poor diet and lifestyle choices. Some patients with heart disease, for example, do not follow their prescribed treatment and often return to the hospital for follow-up care. It's not surprising that some patients do not follow their doctors' orders. But, many of these people do not, and that can have disastrous consequences.
In this study, hospital advertising may not be responsible for reducing the number of readmissions. However, it may help in the improvement of patient safety. It's also important to understand how hospitals can improve patient safety. One method is to use medical insurance claims data to analyze the effect of advertising on readmission rates. In addition, the study also examined the days between initial discharge and readmission, as well as the day of the week that the patient was discharged.
Impact of advertising on perceptions of quality
One recent study looked at the impact of hospital advertising on consumer perceptions of quality. The study compared the five-star CAHPS ratings of hospitals that advertised to those that did not advertise. In fact, the difference in five-star ratings was minimal compared to the four-star CAHPS ratings of hospitals that did not advertise. However, the results were striking if we consider the fact that hospitals that advertise spent more money on advertising than did those that did not. The authors found that hospital advertising has the potential to deceive consumers and undermine public reporting.
Medical advertising has many negative consequences. It may encourage people to make poor decisions regarding treatment and health maintenance. It may also foster unrealistic expectations and encourage people to take unnecessary risks. It may also increase costs of healthcare overall. Further, studies have shown that hospitals that are flooded with advertising are more likely to experience high rates of negative patient evaluations. Therefore, advertising should be limited to the most effective ways to reach and influence consumers.
As health is essential to the overall well-being of individuals, the quality of healthcare service is important. As a result, hospitals are competing for patients' business. As a result, it is important to understand the patient's perspective of the quality of healthcare services. In the healthcare sector, patients' perception of the quality of healthcare services is critical to building trust and positive behavioural intentions. However, the effects of hospital advertising cannot be ignored.
Among the many factors that contribute to patient satisfaction, nurse-patient communication, responsiveness of hospital staff, and environment are important. The results also show that gender has a significant impact on the overall hospital rating. Female patients give lower ratings than male patients. Further, female patients report worse experiences than male patients. It is therefore important to consider the gender of patients when considering the patient's needs and the hospital's response to them.
Effects of advertising on patients
Hospitals spend $1.5 billion annually on advertising, a practice that has generated a lively debate about its ethical and efficacy. Diwas KC, professor of information systems at Emory University's Goizueta Business School, and Tongil Kim, an assistant professor of management at the Naveen Jindal School of Management in Texas, studied the impact of hospital advertising on patients in Massachusetts.
Their analysis found that hospitals that do not advertise were significantly better than those that do. The nonadvertising hospitals were more likely to achieve the five-star rating and CAHPS score, and had lower mortality rates. The difference in mortality rates was particularly striking for hospitals that did not advertise, which were often smaller and more rural. But this difference was not confined to the financial impact. Researchers also found no evidence that hospitals that invest in advertising have higher quality care.
The use of emotional messages should be discouraged in medical service advertisements. Moreover, academic medical centers consistently use emotional messages. Over 60% of advertisements target patients' emotions, and they consistently promote benefits that are not scientifically proven. However, these advertisements are not necessarily misleading. In general, they can lead to poor health and disease decisions. This has implications for hospitals' overall costs. The study will also help physicians determine whether hospitals should make advertising more patient-oriented.
The study also looked at how much money hospitals spent on advertising. Hospitals that advertise were three times bigger than those that did not. They had higher bed counts and higher net income than those that do not advertise. The study did not distinguish between non-advertising and advertising hospitals, so the results can be considered inexact. The researchers concluded that hospital advertising affects quality and patient satisfaction. So, if hospital advertising is effective in attracting patients, it may be a good idea to keep this in mind when choosing a hospital.
While a hospital's advertising budget is a critical element in improving patient care, the value of advertising is largely dependent on the medium used. For example, the Willis-Knighton Health System adopted a triangulation approach to determine the value of its advertising. It studied the use of radio, newspaper, and television ads. They compared the performance of the two groups to an average of all hospitals. Interestingly, the Willis-Knighton Health System had the highest average HRRs among those that advertised while hospitals that did not.
While the amount of money hospitals spend on direct-to-consumer advertising does not directly correlate with publicly reported measures of hospital quality, it does correlate with the financial health of hospitals. Hospitals that advertise more often have higher net incomes and are financially stable. As a result, hospital advertising may be misleading consumers and undermining public reporting efforts. As such, the study is critical in understanding whether high-quality hospitals are responsible for most of the DTC hospital advertising.


Home / Decoration / Sibley Floor Lamp
Sibley Floor Lamp
Sibley Floor Lamp
All of us love our youngsters. We like to see them completely satisfied and hate it after they get harm. And after they begin getting frightened of darkness and might't sleep, particularly in such a beautiful festive season, we all know that one precise factor they might need from Santa. NURSERY LAMPS!
Nursery lamps are night time lamps for nursery used as ornament and as a measure of security for the kids. They arrive in numerous shapes, like a form of an animal that your youngsters are simply studying to spell, or a flower that they're taught is fairly, and are studying to attract, or the moon and few stars up of their ceilings glowing as they go to sleep.
Nursery lamps emit gentle that's not too shiny in order that your youngsters can sleep effectively, however is shiny sufficient for them to see their environment and keep away from accidents at night time. The proper brightness (or dimness) is after they can sleep soundly with out being disturbed by the sunshine even when it's turned on all through the night time. And for you, being a guardian, the aim of this gentle is to verify in your youngsters as a result of it doesn't matter what, you aren't satisfied about their security till you see them secure your self. This additionally makes breast-feeding and altering diapers simpler at night time.
Nursery lamps are very helpful and make issues simpler in day by day lives of oldsters. Nevertheless, for each good factor comes with a worth, it's scientifically confirmed that conserving lights on in your child's room ends in much less restful and sound sleep. Some additionally say that infants being uncovered to gentle on a regular basis could also be confused whether or not its day or night time and can have an effect on their sleep sample.
All of us need a straightforward life, however an ideal one? That we'll by no means get. It's as much as mother and father whether or not to maintain nursery lamps on and compromise their child's sound sleep, or to show off the lights. Or, possibly their child simply can't sleep at nighttime. Then, what is healthier? Keep in mind. Moon and stars that shine and twinkle in such darkish skies are all the time praised by the people.
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Latest news
Bushcraft Day Inspires Year 7
Writing a History of Skipton's Aireville School was a labour of love for former teacher John Tomlinson. In the book John tells how the school started its education journey at its current site in April 1958 and how over the years it has changed, developed, and adapted to meet the needs of a changing community, changing demographic, and a changing need for the school site.
Mr Tomlinson said he had wanted to write a history of the school for some time, as it had played a large part in his life. Another former teacher, David Eager, who taught history at the school, had produced a leaflet some years ago, but he felt it was time to 'expand on David's work'. Through the process of writing the book, Mr Tomlinson talked to many former headteachers, past colleagues, and former students. The work involved collating photos, trawling archives of documents, and reading through many Craven Herald archives from over the years. The book explored how national and local events have moulded the school and its development, how the site and its buildings have changed, as well as the staff and pupils, the many changes in education over the years.
All copies of the book have now sold out and Mr Tomlinson has very generously donated £500 from the sales. Principal Richard McManus commented how appreciative the school were with the very generous donation, which was going to be used to enhance students' experience. After a challenging year for many pupils, it was decided that the money would be used to help support the youngest students in the school. The year group missed out on a traditional transition and due to the many restrictions placed on schools due to Covid19, the money helped them take part in a Bushcraft day.
The day provided students with the opportunity to supplement their standard curriculum with opportunities to learn bushcraft, wilderness, and survival skills, such as fire lighting, shelter building, outdoor cooking, and afforded them the opportunity for pupils to develop their hard and soft skills. Students also developed their confidence, team-working, and leadership skills. On the day, the students had the opportunity to take advantage of the extensive grounds, an opportunity to enjoy the glorious weather, and complete the many activities offered to them. Students commented how enjoyable the day was, the chance to make and meet new people in their year group and work together to complete all the challenges set.
Reviewing the day, Richard McManus commented, in addition to having an amazing time with their friends, learning to work in teams, and building new skills, the students have recognised how they can contribute to the well-being of others by acquiring important and lifelong life-saving skills
< Back to all news stories


I need to change a function named "CalibrationLevel" but first I want to make sure I understand completely it's role in the system, in this case Qt 5.9.
How to do it in Softagram?
 1. Locate the function: just type "CalibrationLevel" to the search bar. Search is case-insensitive.
 2. Right click the function in question and select Inbound View from dropdown menu.
 3. To see all possible call paths, you want to increase the "Dependency Lookup Level". Below I increased it from 1 to 5.
 4. To see the function level details across the call paths you might need to increase the "Detail Level" too (in my example it is 11). Note that I used "Aggregated Incoming Dependency" KPI to highlight the most critical components along the call paths.
In 15 seconds you can get full understanding how your change would affect the whole system, and it could easily save an hour of grepping and constructing an idea of the dependencies in your mind, or drawing it to a piece of paper.
Extra tip:
Now that you have readily proper view settings for call paths, you can check them for any function just by typing the function name to the search bar.
E.g. in the example above, searching again for "CalibrationLevel" would give me the graph of all functions named "CalibrationLevel" (instead of just the one we looked at above), showing their users and possible refactoring targets:
Did this answer your question?


Driver Knowledge Tests Menu
A turn signal that keeps flashing after a turn is very likely to: A turn signal that keeps flashing after a turn is very likely to:
 - A. Confuse other drivers and cause them to turn into your path.
 - B. Damage the electrical system.
 - C. Keep other drivers from seeing your brake light.
 The correct answer is A
 Correct. If you are indicating, drivers may think you are turning and might pull out in front of you.
Motorbike indicators
Newer bikes sometimes have self-cancelling indicators. They can work on the change in angle of the bike, a timer that turns them off after a pre-defined number of seconds, or the change in the speed differential between the front and rear wheel.
However, you should get used to doing it yourself otherwise you might get on another motorbike that doesn't have self-cancelling indicators and you'll forget and cause a problem for yourself when another vehicle pulls out in front of you thinking that you are turning.
Similarly, at the rear, there are integrated taillights and indicators available for some bikes.
Modern indicators have LEDs rather than bulbs.
Indicators come in five main types:
 1. Flush-mounted - these fit in holes in your faring and sit flush (or almost flush) with the surface
 2. Stalk - these sit out from the bike on stalks
 3. Surface-mounted - these indicators sit on the surface and can be used to cover indicator mounting holes on some models of bike.
 4. Numberplate-mounted - these indicators sit either side of your numberplate.
 5. Mirror-mounted - it's possible to get indicators integrated into your mirrors which can clean up the profile of your bike.


text:
- What is dimensional formula?
- What is the formula for current?
- What is K value?
- What is the value of constant k?
- What is the Boltzmann constant in eV?
- What is dimensional formula of surface tension?
- What is dimensions and dimensional formula?
- Why is entropy J K?
- What is dimensional formula of resistance?
- What are the 7 fundamental dimensions?
- Where is Boltzmann constant used?
- What is dimensional formula of Boltzmann constant?
- What is K in Boltzmann's formula?
- What is the dimensional formula of charge?
- What is the SI unit of charge?
- What is dimensional formula of time?
- What is r in pV nRT?
- What is the significance of Boltzmann constant?
What is dimensional formula?
The dimensional formula is a compound expression showing how and which of the fundamental quantities are involved in making that physical quantity.
The dimensional equation of a physical quantity is an equation, equating the physical quantity with its dimensional formula..
What is the formula for current?
Current is usually denoted by the symbol I. Ohm's law relates the current flowing through a conductor to the voltage V and resistance R; that is, V = IR. An alternative statement of Ohm's law is I = V/R.
What is K value?
(N·s2/C2)c2. The Coulomb constant, the electric force constant, or the electrostatic constant (denoted ke, k or K) is a proportionality constant in electrostatics equations. In SI units it is equal to 8._PHONE_(14)×109 kg⋅m3⋅s−2⋅C−2.
What is the value of constant k?
The symbol k is a proportionality constant known as the Coulomb's law constant. The value of this constant is dependent upon the medium that the charged objects are immersed in. In the case of air, the value is approximately 9.0 x 109 N • m2 / C2.
What is the Boltzmann constant in eV?
Click symbol for equationBoltzmann constant in eV/KNumerical value8.617 333 262… x 10-5 eV K-1Standard uncertainty(exact)Relative standard uncertainty(exact)9 more rows
What is dimensional formula of surface tension?
Surface Tension (T) = Force × Length-1..... ( 1) Since, Force = Mass × Acceleration. And, acceleration = velocity × time-1 = [L T-2] ∴ The dimensional formula of force = M1 L1 T-2.... (
What is dimensions and dimensional formula?
DIMENSIONS are the powers to which the fundamental quantities are raised to represent other physical quantities. DIMENSIONAL FORMULA is an expression in which dimensions of a physical quantity is represented in terms of fundamental quantities.
Why is entropy J K?
Thus, under appropriate conditions and definitions, the change in entropy is the amount of heat transferred divided by the temperature. … Thus, under appropriate conditions and definitions, the change in entropy is the amount of heat transferred divided by the temperature. Thus it has the units of J K-1.
What is dimensional formula of resistance?
Therefore, resistance is dimensionally represented as M L2 T-3 I-2.
What are the 7 fundamental dimensions?
In total, there are seven primary dimensions. Primary (sometimes called basic) dimensions are defined as independent or fundamental dimensions, from which other dimensions can be obtained. The primary dimensions are: mass, length, time, temperature, electric current, amount of light, and amount of matter.
Where is Boltzmann constant used?
In classical statistical mechanics, Boltzmann Constant is used to expressing the equipartition of the energy of an atom. It is used to express Boltzmann factor. It plays a major role in the statistical definition of entropy. In semiconductor physics, it is used to express thermal voltage.
What is dimensional formula of Boltzmann constant?
Dimension Formula of Boltzmann Constant R is the universal gas constant, whose value is 8.314 J/K-mol, and its dimensional formula is [M1L2T−2K−1].
What is K in Boltzmann's formula?
where kB is the Boltzmann constant (also written as simply k) and equal to 1.38065 × 10−23 J/K. In short, the Boltzmann formula shows the relationship between entropy and the number of ways the atoms or molecules of a thermodynamic system can be arranged.
What is the dimensional formula of charge?
Therefore, the electric charge is dimensionally represented as [M0 L0 T1 I1].
What is the SI unit of charge?
coulombThe SI derived unit of electric charge is the coulomb, which is defined as an ampere second.
What is dimensional formula of time?
The equations obtained when we equal a physical quantity with its dimensional formulae are called Dimensional Equations. The dimensional equation helps in expressing physical quantities in terms of the base or fundamental quantities….Dimensional Equations.Physical QuantityDimensional EquationTime Period of wave[T] = [M0L0 T-1]6 more rows
What is r in pV nRT?
Pressure is inversely proportional to volume: =, where a > 0 is a constant. … The ideal gas law is: pV = nRT, where n is the number of moles, and R is universal gas constant. The value of R depends on the units involved, but is usually stated with S.I. units as: R = 8.314 J/mol·K.
What is the significance of Boltzmann constant?
The physical significance of k is that it provides a measure of the amount of energy (i.e., heat) corresponding to the random thermal motions of the particles making up a substance. For a classical system at equilibrium at temperature T, the average energy per degree of freedom is kT/2.


text: Exquisite workmanship and lavish use of precious materials distinguish this sword as a princely weapon and exemplifies the opulence and refinement of Ottoman luxury arts. Almost identical to a yatagan (now in the Topkapi Palace, Istanbul) made in 1526–27 by the court jeweler Ahmed Tekel, for the Ottoman sultan Süleyman the Magnificent (r. 1520–66), this sword was undoubtedly made in the same imperial workshop. The gold incrustation on the blade depicts a combat between a dragon and a phoenix against a background of foliate scrolls. These figures, like the gold-inlaid cloud bands and foliate scrolls on the ivory grips, are Chinese in inspiration, and were probably introduced into Ottoman art through contacts with Persia. This sword is one of the earliest known yatagans, distinctly Turkish weapons characterized by a double-curved blade and a hilt without a guard. Yatagans were commonplace in Turkey and the Balkans in the eighteenth and nineteenth centuries and served as sidearms for the elite troops known as janissaries.


Question: What Does The Word Boycott Most Likely Mean?
What was Boycott Class 10?
Boycott is an act of refusal to buy, use or participate.
Here, Indians boycotted British goods in order to protest against the British rule..
What is a meaning of the word boycott?
What does the word boycott mean in a sentence?
verb (used with object) to combine in abstaining from, or preventing dealings with, as a means of intimidation or coercion: to boycott a store. to abstain from buying or using: to boycott foreign products.
What is a synonym and antonym for boycott?
ˈbɔɪˌkɑːt) Refuse to sponsor; refuse to do business with. Synonyms. ostracize ostracise. Antonyms. patronize patronise confront.
Where did the word boycott come from?
The word boycott entered the English language during the Irish "Land War" and derives from Captain Charles Boycott, the land agent of an absentee landlord, Lord Erne, who lived in Lough Mask House, near Ballinrobe in County Mayo, Ireland, who was subject to social ostracism organized by the Irish Land League in 1880.


Creating and Deleting New Meetings
Creating a New Meeting
Go to Meetings > Add Meeting
1. Enter the name, date, and time for your event.
2. Use the WYSIWYG (what you see is what you get) editor to insert images and hyperlinks to the description.
Please note you can select No fixed meeting date if you don't have a date for a designated meeting/event.
You can set the Registration to three different options:
None means that the meeting will show on your calendar but won't have any registration component for people. You can still register people while logged into your Databank through their record.
Public adds a registration form to the meeting detail on your calendar and anyone visiting your calendar can sign up.
Private means that the meeting will show on your calendar but it won't display a registration form. You will be able to email a private link to people to have them register.
1. Set Status
Published places the meeting on your calendar form.
Unpublished will not submit your meeting to the calendar form.
2. Set the Meeting Type and Activity
If you want to add a new type just enter it in the blank field. If you have multiple calendars for your Organization you can use the Meeting Type to determine which meetings to show on which calendar.
3. Set the amount of Attendees
If your meeting will have a maximum size enter that in the Max. Attendees field.
You can also set the maximum amount a single member can register in the Max. Per Member field.
Enter a BCC Email so you can know when people register for your meeting.
Enter a location name and the details of the location. If you've already entered the information before for a different meeting you can select it from the drop down menu.
Click Submit at the bottom right of the page to finish.
Click Delete the at the bottom left to remove this event from your Databank.
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text:
- SEE ALSO
Mac::Apps::Anarchie - Interface to Anarchie 2.01+
use Mac::Apps::Anarchie; $ftp = new Mac::Apps::Anarchie; _TAG_ description for the rest
This is a MacPerl interface to the popular MacOS shareware FTP/archie client, Anarchie. For more info, see the Anarchie documentation.
Also required is the Mac::Apps::Launch module, which requires MacPerl 5.1.4r4.
NOTE: for some explanations of methods, drop Anarchie on Script Editor, and check the Anarchie docs.
Before using, you must autosplit the module. See version notes for 1.4 below.
$ftp->open(ALIAS); $ftp->quit; $ftp->showabout; $ftp->close; $ftp->closeall; $ftp->undo; $ftp->cut; $ftp->copyclip; $ftp->paste; $ftp->clear; $ftp->selectall;
NOTE: * denotes compatability with Fetch. Fetch does not use the variables SOCKS, FIRE, BINARY, or TYPE. Fetch implements some of these methods differently than Anarchie. To use Fetch instead of Anarchie for these methods, call the method:
There are two forms of each of the following methods: "method" and "methodURL". The methodURL version takes the user name, password, host and path in the URL instead of separately. URLs are usually in the form:
See Anarchie docs for more info on URLs.
Also, the host, username, password, proxy firewall and socks firewall can be preset and then omitted during the method call. This saves a lot of code writing if you are going to make multiple calls to the same host. If a method explicitly names any of those strings, it overrides presets. If username and password are not specified anywhere, FTP is done anonymously.
$ftp->host(HOST); $ftp->user(USER); $ftp->pass(PASS); $ftp->fire(FIRE); $ftp->socks(SOCKS);
If you don't want MacPerl to wait for Anarchie to finish what it is doing, then call this with the value 0. You can change it back to 1 if you do want it to wait. The initial setting is 1.
- fetch *
$ftp->fetch(FILENAME [, PATH, BINARY, TYPE, HOST, USER, PASS, FIRE, SOCKS]); $ftp->fetchURL(FILENAME [, URL, BINARY, TYPE, FIRE, SOCKS]);
Fetches file and saves to FILENAME on local drive. BINARY is boolean for whether file is binary or ascii. TYPE is the creator code to link file to. NOTE: for Fetch, FILENAME must be an existing directory name, NOT a filename. For Anarchie, FILENAME must be a file if the fetched item is a file or a directory if the fetched item is a directory. Anarchie will create FILENAME on the local drive if it does not exist.
- store *
$ftp->store(FILENAME [, PATH, BINARY, HOST, USER, PASS, FIRE, SOCKS]); $ftp->storeURL(FILENAME [, URL, BINARY, FIRE, SOCKS]);
Stores file FIELNAME from local drive to remote location specified.
- rename *
$ftp->rename(NEWNAME [, PATH, HOST, USER, PASS, FIRE, SOCKS]); $ftp->renameURL(NEWNAME [, URL, FIRE, SOCKS]);
Renames file NEWNAME to value in PATH or URL.
- remove *
$ftp->remove([PATH, HOST, USER, PASS, FIRE, SOCKS]); $ftp->removeURL([URL, FIRE, SOCKS]);
Removes file/directory specified in PATH or URL.
- mkdir *
$ftp->mkdir([PATH, HOST, USER, PASS, FIRE, SOCKS]); $ftp->mkdirURL([URL, FIRE, SOCKS]);
Make directory specified in PATH or URL.
- sendcommand *
$ftp->sendcommand([PATH, HOST, USER, PASS, FIRE, SOCKS]); $ftp->sendcommandURL([URL, FIRE, SOCKS]);
Send raw FTP command.
- index *
$ftp->index([PATH, HOST, USER, PASS, FIRE, SOCKS]); $ftp->indexURL([URL, FIRE, SOCKS]);
Display index listing. SITE INDEX command must be implemented on host.
- list *
$ftp->list(FILENAME, [PATH, HOST, USER, PASS, FIRE, SOCKS]); $ftp->listURL(FILENAME, [URL, FIRE, SOCKS]);
List files in a directory, put into file FILENAME. Fetch apparently only lists to the screen, while Anarchie lists to a file. For Fetch, just put any old text in place of FILENAME and it should work just fine.
$ftp->nlist(FILENAME, [PATH, HOST, USER, PASS, FIRE, SOCKS]); $ftp->nlistURL(FILENAME, [URL, FIRE, SOCKS]);
List names of files in a directory, put into file FILENAME.
Anarchie Suite, Part Deux
NOTE: These methods are NOT supported at all by Fetch.
$ftp->find(FILENAME [, SERVER, MAX, CASE, REGEX, URL]);
Find file containing text FILENAME in Archie SERVER with maximum matches MAX. CASE is boolean (0 or 1) for case sensitive. REGEX is 0, 1 or 2 for denoting that FILENAME is a substring, pattern, or regular expression.
Find Mac file containing text FILENAME on Ambrosia's Mac server.
$ftp->showtranscript; $ftp->showarchie; $ftp->showget; $ftp->updateserverlist; $ftp->showlog; $ftp->showmacsearch; $ftp->showtips;
$ftp->geturl(URL [, FILENAME]);
- v.1.4, January 3, 1998
Basic cleanup. Requires MacPerl 5.1.4r4 or better now.
- v.1.4, November 3, 1997
Pulled out main functions as autosplit/autoload files. Before using, you must run a script such as the following, in order to AutoSplit the routines:
#!perl -w use AutoSplit; $dir = 'HD:MacPerl:site_perl'; autosplit("$dir:Mac:Apps:Anarchie.pm","$dir:auto",0,1,1);
This also means that the
Mac::Apps::Anarchieclass is no longer aliased to simply
- v.1.3, October 15, 1997
waitreplymethod. Fixed error catching. Erorrs still are not descriptive, but now they are reported. :-)
- v.1.2, October 13, 1997
Get app launching from Mac::Apps::Launch, fixed descriptor disposing.
- v.1.1 May 4, 1997
Whoops, fixed something I broke in the AEPutParamDesc stuff.
- v.1.0 May 4, 1997
Finally got around to cleaning it up. Only minor changes.
- v.0.2 March 20, 1997
First 'public' beta.
- regex find
Still having problems with the substring/pattern/regex option on "find". I am not sure what the problem is.
- Anarchie Home Page
Chris Nandor _URL_
Copyright (c) 1998 Chris Nandor. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. Please see the Perl Artistic License.
Version 1.50 (03 January 1998)
2 POD Errors
The following errors were encountered while parsing the POD:
- Around line 495:
You forgot a '=back' before '=head2'
- Around line 499:
'=item' outside of any '=over'


Principle 3: Competence
A Stamford Privee member shall provide services to clients competently and maintain the necessary knowledge and skill to continue to do so in those areas in which the designee is engaged.
One is competent only when he or she has attained and maintained an adequate level of knowledge and skill, and applies that knowledge effectively in providing services to clients. Competence also includes the wisdom to recognize the limitations of that knowledge and when consultation or client referral is appropriate. In addition to assimilating the common body of knowledge required and acquiring the necessary experience, we shall make a continuing commitment to learning and professional improvement.


Back to Kemp Acoustics Home next up previous contents
Next: Introduction to the study Up: thesis Previous: List of Figures Contents
List of Tables
 1. Trumpet section dimensions
 2. Thermodynamic constants
 3. MLS element sequence for $m=4$
 4. Recursion relations for MLS of length $2^m-1$
 5. Zeros of the Bessel function $J_1$ to 7 decimal places
Jonathan Kemp 2003-03-24


Four steps for testing housing material performance
When exposed to commonly used aggressive disinfectants and drugs, many materials used in medical devices can crack, craze, discolor, and become sticky. Currently, there are no industry standards for evaluating surface compatibility. That's why Eastman developed a 4-step test method based on ASTM standards to better understand why plastics fail and how different plastics perform in the real world.
 1. Select the appropriate jig.
 2. Load flex bars onto jig.
 3. Apply chemicals to the flex bars.
 4. Perform reverse side impact test.
Step 4 is the differentiating step in this testing protocol. While visual inspection after step 3 may reveal changes in some plastics, there may be cracks or crazes that are not visible to the naked eye or identified by weight or dimensional changes. By performing Step 4, you are better able to predict the reliability of a device after exposure.
Read our Disinfect with Confidence brochure for more details on each step of the process, and check out this video.
Ultimately, this test should help you confidently choose the best material for your next project.
Learn more about Eastman's medical grade polymers for medical device housings and hardware at


text:
The Hamilton-Norwood scale is a way of measuring male pattern baldness. It was introduced by Dr. James Hamilton in the 1950s and later revised and updated by Dr. O'Tar Norwood in the 1970s.
There are 2 main types of balding, anterior (front) and vertex (back), as this alternate view of the Norwood scale shows a bit more clearly.
Stages on the scale are often abbreviated to nw1, nw2, nw3a etc. Another slight variation on the scale is shown below.
Baldness in women takes a different pattern, and is measured on the Ludwig Scale.
I intend to give each of my postings a rating on the Norwood scale, but remember that this is only personal opinion and sometimes I may get it wrong. The Norwood scale is a less than perfect way of measuring baldness, but it is the best and most widely recognised way we have.
An alternative look at the Norwood Scale can be found at shortandbald.net
3 years ago


Adult Learner
Systems Change
Adult Learner > Factors > Socioeconomic Status
Socioeconomic Status
Factor Connections
How Socioeconomic Status connects to...
Socioeconomic Status (SES) refers to an individual or family's social standing as compared to other families. It is usually measured by a combination of factors, including a family's education, occupation, and income, as well as access to social and cultural resources. Socioeconomic Status and educational attainment are tightly interconnected, and adult learners are often seeking to improve their Socioeconomic Status through continuing education and training opportunities.
Main Ideas
According to the National Center for Education Statistics, 30% of adults living at or below the federal poverty line have not completed their high school credential. Many adults who are experiencing poverty struggle with basic reading, math, and digital skills, and having a high school credential does not guarantee that basic skills are in place.
In addition to inequitable access to high quality education and training opportunities, people who experience poverty or earn less than a family-sustaining wage may also be impacted by: housing insecurity, food insecurity, and job insecurity.
 - Housing insecurity and mobility often affects low-income families such as those who have high housing costs relative to their income. This disparity can result in difficulty paying monthly rent and utilities, which can lead to housing instability, eviction, and in some cases, homelessness.
 - Food insecurity refers to lack of access to sufficient amounts of nutritious food. People experiencing food insecurity may also live in food deserts, areas where there is limited access to grocery stores or farmer's markets that supply healthy and affordable food.
 - Job insecurity and unemployment also negatively impact adults living below family-sustaining wages, and can be major sources of psychological stress. It is important to note that unemployment disproportionately affects Black men, who are historically more likely to experience mass incarceration and have limited opportunities to advance in education, build their skills, and access well-paying jobs.
Additional factors such as the cost of continuing education, childcare, and transportation may also prevent individuals with lower SES from participating in adult and continuing education opportunities. The cost of digital devices and reliable broadband internet access may also widen what is often referred to as the digital divide. For many individuals, the childhood trauma associated with economic hardship and lack of access to financial, social, and educational resources at home and in the community can have long-term effects on academic achievement, health, and well-being into adulthood.
Learn More
View Measures and References


text:
In Japan, it is said that brush is to be chosen according to a rule of four virtues. These are:
尖 (sen) - The brush tip must be sharp and pointy. There should be no irregularities in symmetry or thickness of hair of the tuft tip. This is especially important for brushes used for writing that requires precision (fine lines in sumi-e, standard script, etc.)
斉 (sei) - The brush tuft ought to be well arranged. In other words that hairs are well organized and do not stick out, they are not broken and are of a uniform shape and quality.
円 (en) - The brush tuft needs to be well rounded and symmetrical in its cross section. While looking at the brush from its tip, the tuft should form a perfect circle. Also, with the hairs released, the tuft should form a perfect cone shape with a flat top.
健 (ken) - The brush needs to be healthy and full of vigour. The hair (especially at the tuft base) should be flexible and responsive. No damaged hairs should be visible. Also the brush axis should be straight and free of cracks. Bamboo shafts tend to crack, especially when they get wet during the washing of the brush. Expensive brush manufacturers usually offer to change the brush shaft free of charge.
On top of that, the brush needs to suit its purpose. Depending on what we intend to write or how we want to do it, different types or sizes of brush should be chosen. Calligraphy is infinite, and so are the brush choices. It may take years before a calligrapher senses instinctively which brush goes well with his style and personality.
Continue to Calligraphy Brush Anatomy
Back to Calligraphy Brush Sizes
Back to Calligraphy Brush


Quick Answer: What Are 60 Year Olds Called?
How often do 70 year olds make love?
Sexual frequency did decrease with age for women, although almost a quarter of partnered women over age 70 had sex more than 4 times a week, according to the survey.
Even if men and women do have sex more frequently, it doesn't mean they are happier..
What age is middle age for a woman?
This time period in the life of a person can be referred to as middle age. This time span has been defined as the time between ages 45 and 60. Many changes may occur between young adulthood and this stage.
Can I retire and collect Social Security at 55?
You can start receiving your Social Security retirement benefits as early as age 62. However, you are entitled to full benefits when you reach your full retirement age. If you delay taking your benefits from your full retirement age up to age 70, your benefit amount will increase.
What do you call a person in their 60's?
Sexagenarian: Someone in his or her sixties. Septuagenarian: Someone in his or her seventies. Octogenarian: Someone in his or her eighties. Nonagenarian: Someone in his or her nineties.
What are 70 year olds called?
A septuagenarian is someone in their 70s (70 to 79 years old), or someone who is 70 years old.
Is 55 considered elderly?
Note that by these definitions, "old" in the 1920s — 55 — is now considered "middle aged" today, and "very old" in the 1920s — 65 — is now considered merely "old" today. … By these measures, women today transition out of middle age around 65, a number that has increased from the late 40s in the 1920s.
What do you call a 60 year old woman?
Noun. sexagenarian (plural sexagenarians) A person who is 60 years old or between the ages of 60 and 69.
What can you do at 60 years old?
Be HealthierRide horseback.Learn a new recipe.Take a Zumba or dance class.Try going vegetarian.Learn yoga.Take a self-defense course.Learn to meditate.Grow your own fruits and veggies.
What is the age range for the elderly?
Although there are different ways to classify this population, some studies have classified elderly adults between the ages of 65 and 74 years as youngest-old, those between ages 75 and 84 years as middle-old, and those aged over 85 years as oldest-old [5].
What are old people called?
Senior citizen Synonyms include old age pensioner or pensioner in British English, and retiree and senior in American English. Some dictionaries describe widespread use of "senior citizen" for people over the age of 65.
What are 50 year olds called?
A person between 50 and 59 is called a quinquagenarian. A person between 60 and 69 is called a sexagenarian. A person between 70 and 79 is called a septuagenarian. A person between 80 and 89 is called an octogenarian.
Is 60 years old considered elderly?
The term "senior citizen" typically refers to someone who is retired and above the age of 60 or 65.
What age is over the hill?
Some sites proclaim that, as soon you turn 40, you're over the hill. Apparently, forty is the average mid-point in life. Before that, you were a high-achieving young person. But after your 40th birthday, you are on the slow, irreversible decline to boring, musty old-age.
What should I expect at 60 years old?
Your skin turns drier and itchier and may look like crepe paper or tissue. Wrinkles, age spots, creases, and bruises become more noticeable. Your sweat glands also get less active. That means you might not sweat as much, but wounds on your skin may take longer to heal.
How do you age gracefully in your 60s?
Tips for aging gracefullyBe kind to your skin. Your skin is your body's largest organ. … Exercise. … Mind your diet. … Mental health matters. … Stay physically active. … Lower your stress. … Quit smoking and decrease alcohol consumption. … Get enough sleep.More items…•
What is the politically correct term for senior citizens?
Pensioners is just okay. And elders is a term embraced by those that see it as a sign of respect. Over-55, over-65, and of course, the ever-popular baby boomers (for the younger old people) are phrases that are widely accepted. Unless you're referring to a frail 99-year-old, please, oh please, do not use elderly!
At what age are you considered over the hill 40 or 50?
To consider that age 50, you are old and past your prime is a matter of judgement. To someone else age 40 or may be age 60 may be considered as being over the hill.
Is 50 a old age?
The World Health Organisation believes that most developed world countries characterise old age starting at 60 years and above. However, this definition isn't adaptable to a place like Africa, where the more traditional definition of an elder, or elderly person, starts between 50 to 65 years of age.


OpenWindows Advanced User's Guide
3.3.2 Print Working Directory (pwd)
The command pwd (print working directory) tells you where you are in the file system hierarchy:
$ pwd
Your output will look somewhat different from that in the example, as your directory structure will be different. Remember that your working directory is your current location within the file system hierarchy.


Puddle Ducks
Sutton Coldfield
Baby swimmers love swimming for life! Puddle Ducks is a fun and friendly swimming programme offering unique baby swimming, toddler swimming and child swimming classes through franchises across the UK.
Babies and children can join our swimming classes at any age from birth; developing from water babies to confident swimmers without even realising they are learning to swim. By engaging each child's abilities and natural affinity with water, Puddle Ducks offer simple steps to a lifetime love of swimming. Children learn lifesaving, swimming and underwater skills and are often able to swim 10 metres or more before they start school.
Add review


text:
Research & Publication
Abstract:Internet is one of the imperative explosion in communication and information retrieval. This massive development of web prompts host millions of web pages in heterogeneous platform. Due to the lack of a standard mechanism to guarantee the nonexistence of a web page before hosting them in the server leads to increases the near duplicate pages in the internet. These near duplicate contents can exist either by intentional or accidental. The issue of finding near-duplicate web pages has been a subject of research in the database and web-scan groups for a few years. Since most winning content mining strategies received term-based methodologies, they all experience an issues of word synonym and substantial number of comparison. In this paper we propose a method, which deal with the detection of near and duplicate web pages detection by using an extended term document weighting scheme, sentence level features and simHash technique. The existence of these near and duplicate web pages causes the problems that range from network band width utilization, storage cost, reduce the performance of search engines by duplicated content indexing and increase load on a remote host.


Overview | Related MBeans | Attributes | Operations
These parameters control what should happen to messages when failures occur. They allow the adminstrator to control error destinations, logging and other actions that might be taken when a message can not be delivered or when other failures are detected
 - Deployer
Access Points You can access this MBean from the following MBean attributes:
Related MBeans
This section describes attributes that provide access to other MBeans. For more information about the MBean hierarchy, refer to WebLogic Server MBean Data Model.
 The name of the target error destination for messages that have expired or reached their redelivery limit. If no error destination is configured, then such messages are simply dropped. If a message has expired or reached its redelivery limit, and the Expiration Policy is set to Redirect, then the message is moved to the specified Error Destination.
 For standalone destinations, an error destination must be another standalone destination that is targeted to the same JMS server as the destinations for which the error destination is defined. For uniform distributed destinations (UDDs), the error destination must be a another UDD that shares the same subdeployment (i.e., targets) as the current UDD.
 This attribute is dynamically configurable, but only incoming messages are impacted; stored messages are not impacted.
 Privileges Read/Write
 Relationship type: Reference.
 This section describes the following attributes:
 The policy that defines what information about the message is logged when the Expiration Policy is set to Log. The valid logging policy values are:
 When specifying multiple values, enter them as a comma-separated list. The %header% and %properies% values are not case sensitive. For example, you could use "%header%,%properties%" for all the JMS header fields and user properties. However, the enumeration of individual JMS header fields and user-defined properties are case sensitive. To enumerate only individual JMS header fields you could use "%header, name, address, city, state, zip".
 Note: The JMSMessageID field is always logged and cannot be turned off. Therefore, if the Expiration Logging Policy is not defined (i.e., null) or is defined as an empty string, then the output to the log file contains only the JMSMessageID of the message.
 Deprecated. Replaced by MessageLoggingParamsBean
 Privileges Read/Write
 The message Expiration Policy to use when an expired message is encountered on a destination. The valid expiration policies are:
 None - Same as the Discard policy; expired messages are simply removed from the destination.
 Discard - Removes expired messages from the messaging system. The removal is not logged and the message is not redirected to another location. If no value is defined for a given destination (i.e., None), then expired messages are discarded.
 Log - Removes expired messages from the system and writes an entry to the server log file indicating that the messages have been removed from the system. The actual information that is logged is defined by the Expiration Logging Policy.
 Redirect - Moves expired messages from their current location to the Error Destination defined for the destination. The message retains its body, and all of its properties. The message also retains all of its header fields, but with the following exceptions:
 It is illegal to use the Redirect policy when there is no valid error destination defined for the destination. Similarly, it is illegal to remove the error destination for a destination that is using the Redirect policy.
 The Maximum Message quota is only enforced for sending new messages. It is ignored when moving messages because of the Redirect policy.
 Privileges Read/Write
 Default ValueDiscard
 Legal Values
 - Discard
 - Log
 - Redirect
 The number of redelivery tries a message can have before it is moved to the error destination. This setting overrides any redelivery limit set by the message sender. If the redelivery limit is configured, but no error destination is configured, then persistent and non-persistent messages are simply dropped (deleted) when they reach their redelivery limit.
 The default value (-1) specifies that the destination will not override the message sender's redelivery limit setting.
 Note: The number of times a message has been redelivered is not persisted. This means that after a restart, the number of delivery attempts on each message is reset to zero.
 This attribute is dynamically configurable, but only incoming messages are impacted; previously sent messages continue to use their original redelivery limit.
 Privileges Read/Write
 Default Value-1
 Minimum value-1
 Maximum value2147483647
 This section describes the following operations:
 This is used to find the sub-deployment-name for this destination.
 Operation Name"findSubDeploymentName"
 This is used to find the template bean for this destination
 Operation Name"getTemplateBean"
 Operation Name"isSet"
 ParametersObject [] { propertyName }
 - propertyName is an object of type java.lang.String that specifies:
 property to check
 SignatureString [] { "java.lang.String" }
 Returns boolean
 - java.lang.IllegalArgumentException
 IllegalArgumentException if propertyName is not a recognized property
 Restore the given property to its default value.
 Operation Name"unSet"
 ParametersObject [] { propertyName }
 - propertyName is an object of type java.lang.String that specifies:
 property to restore
 SignatureString [] { "java.lang.String" }
 Returns void
 - java.lang.IllegalArgumentException
 UnsupportedOperationException if called on a runtime implementation.


text:
Date: December 2009
Creator: Myers, Joyce Eady
Description: The purpose of this study was to determine the extent to which faith-based preschools promote spiritual development in preschoolers. The participants in the study were faith-based early childhood teachers and administrators from seven states. Early childhood professionals representing 11 Christian faith traditions completed written surveys or online surveys. A total of 201 faith-based educators completed the survey; 20 respondents participated in semi-structured interviews. The concurrent triangulation mixed-method design provided data on 8 program dimensions which support children's spiritual development: prayer, Bible literacy, worship, building character, service opportunities, assessment, parental involvement and context. I analyzed quantitative data using descriptive and inferential statistics. All items were examined using mean, standard deviation, frequency, and percentages. Qualitative data gathered from semi-structured interviews were coded and analyzed using NVivo8® qualitative analysis software (QSR International, Inc., Cambridge, MA, _URL_). From this data I identified the extent to which faith-based preschool programs support children's spiritual development through the practices of prayer, Bible literacy, worship, building character, service opportunities, assessment, parental involvement and context. Data analyses revealed statistically significant differences in faith-based teachers' hours of training in children's spiritual development across all program practice dimensions. A key finding of the study was that training in children's spiritual development...
Contributing Partner: UNT Libraries


text:
In November, voters in California will vote on Proposition 2, which seeks to increase cage sizes for egg laying hens, pregnant pigs and veal calves. The new regulations, which would go into effect in 2015, would require cages to be large enough to allow these animals to be able to stand up, lie down, turn around and to be able to fully extend their limbs without touching the side of an enclosure or other egg-laying hens.
To show the size of some animals' quarters in large-scale farm operations, Oprah stands with replicas of cages and crates for each animal affected by Proposition 2. In an egg-laying hen cage, five to six hens could be in a single cage. The typical crate for a young male calf being raised for veal has enough room for him to stick his head out. Pregnant pigs—which can weigh more than 500 pounds—are about 5 to 6 feet long, while the cages they live in are about 7 feet long.
Those who support Proposition 2 say these animals have the right to more space during their lives. Opponents of Proposition 2, including farmers and industry representatives, say the new law would drive up costs, put farmers out of business and end the egg industry in California, and deny consumers the right to choose less-expensive food.


text:
- About this Journal ·
- Abstracting and Indexing ·
- Aims and Scope ·
- Article Processing Charges ·
- Author Guidelines ·
- Bibliographic Information ·
- Citations to this Journal ·
- Contact Information ·
- Editorial Board ·
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Journal of Control Science and Engineering
Volume 2012 (2012), Article ID 964242, 5 pages
Discrete Model Reference Adaptive Control System for Automatic Profiling Machine
College of Electromechanical and Information Engineering, Dalian Nationalities University, Dalian 116605, China
Received 3 December 2011; Revised 15 May 2012; Accepted 6 June 2012
Academic Editor: Yunjun Xu
Copyright © 2012 Peng Song et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Automatic profiling machine is a movement system that has a high degree of parameter variation and high frequency of transient process, and it requires an accurate control in time. In this paper, the discrete model reference adaptive control system of automatic profiling machine is discussed. Firstly, the model of automatic profiling machine is presented according to the parameters of DC motor. Then the design of the discrete model reference adaptive control is proposed, and the control rules are proven. The results of simulation show that adaptive control system has favorable dynamic performances.
Automatic profiling machine is a movement system which has a high degree of parameter variation and high frequency of transient process, and it requires an accurate control in time. The traditional linear control methods, such as PID, cannot meet present needs or requirements of advanced performance. The adaptive control not only solves the problem that the control plant cannot be observed directly, but also improved the abilities of resisting interference. The applications of adaptive control to movement system are widespread [2–4], but it is infrequent in automatic profiling machine. A practical adaptive controlling scheme is proposed for automatic profiling machine in. In this paper, a discrete model reference adaptive control (MRAC) method is applied to automatic profiling machine. The discrete control method is convenient for program and contributes to application of adaptive control theory in practice.
2. The Mathematics Model
The control system is double closed-loop control system whose current loop is PI control and speed loop is MRAC. The DC motor parameters of automatic profiling machine are shown in Table 1. The equivalent plant of speed loop is consisted of current loop and motor, and the transfer function is
3. The Design of MRAC System
The difference equation of the plant is where and are the output and input of the plant, respectively; is delay operator; is the discrete-time variable.
The difference equation of the reference model is where and are the output and input of the reference model.
The output error and its prediction are given by where and the other variables with "∘" represent the predictions.
The structure of the adaptive control system is shown in Figure 1 where
From Figure 1, the following relationship can be obtained
According to the Hyperstability theory, the discrete system control laws are where where where
cannot be found directly in the operations above, so it can be replaced by. According to (10), becomes
The prediction error can be gained:
4. Simulation Studies
The reference model takes the form as follows:
The simulation results are shown in Figures 3–5. To make a calculation, the percentage overshoot is 6%, the rise time is 1 s, the settling time is 2 s (). Figure 3 is shown that the maximal error value is less than 40 r/min, so the control plant could better track reference model. Input the interference signal into the front of plant transfer function between 10 s and 20 s. The simulation results (in Figure 4) indicate that the control plant could be stable in 2 seconds. Input white noise into the reference input of plant not the reference input of model, and the result is shown in Figure 5. Obviously the figure has no visible variation. So the control system has better abilities of resisting interference.
The discrete model reference adaptive control system of automatic profiling machine is discussed in this paper. The results of simulation show that adaptive control system has favorable dynamic performance. The discrete design method is easy to realize by computer. The work in this paper will lay a foundation for the application of adaptive control in practice.
This paper was supported by the National Science and Technology Support Program Project (2009BAH41B05) and the Fundamental Research Funds for the Central Universities.
- S. C. Wu and Z. Q. Wu, Adaptive Control, China Machine Press, Beijing, China, 2005.
- G. K. Xu and X. C. Zhao, The Adaptive Control of Drive System For HS2000 Electric Vehicle, The Research and Development of China Electric Vehicle, Beijing Institute of Technology Press, Beijing, China, 2005.
- P. Song, W. Q. Long, G. K. Xu, and X. C. Zhao, "Research on discrete-time model reference adaptive control of electric vehicle driven motor," Journal of System Simulation, vol. 19, no. 18, pp. 4261–4264, 2007.
- G. K. Xu, L. R. You, X. C. Zhao, P. Song, and C. H. Liu, "A research on adaptive speed controller of a 4M gantry planning machine," Control Theory and Applications, vol. 24, no. 5, pp. 846–850, 2007.
- L. R. You, F. Qiao, and G. K. Xu, "Adaptive controller for automatic profiling machines," Control Theory and Applications, vol. 21, no. 6, pp. 1025–1028, 2004.
- G. K. Xu, Z. Y. Chu, and S. C. Wu, The Adaptive Controller Design For Movement System, Chinese Technology Press, Beijing, 2004.


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At some point in your life, you may need to call the emergency services such as firemen, police, or medical personnel. By being prepared for calling the emergency services, you can get the help you need much more quickly which can often make a big difference. Parents should also teach their children about when and how to call for help.
The principal emergency services are the "blue light" services that respond to normal emergencies in Ireland namely An Garda Síochána, the Ambulance Service, the Fire Service and the Irish Coast Guard. These principal emergency services would be the 'first responders' in most emergency situations.
In Ireland we have two emergency numbers, 999 and 112.
112 works also in all EU countries and from any phone, free of charge. If a family member or friend is travelling within the EU soon, check that they know what number to call in case of any emergency – under stress of an accident, it could prove vital.
Remember when calling 112 (or 999), 'stay calm, stay focused and stay on the line'.


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"How many ways can the letters in the word SLUMGULLION be arranged so that the three L's precede all the other consonants?"
My work is below: Can someone also solve this ONLY using the multiplication rule, permutations, and permutations with repetitions?
We have 3 L's and the other 4 consonants are S,M,G,N. That is, our consonants are LLLSMGN, call them all X for the moment. Then we have XXXXXXXUUIO. The number of arrangements of these letters is $\frac{11!}{7!2!}$. Hence the answer is $4!*\frac{11!}{7!2!}$ since there are $4!$ ways to arrange the 4 consonants other than the L's.
share|improve this question
Hmm, I got the same answer as you. – JohnJamesSmith Mar 26 '12 at 2:12
Your reasoning is correct. I also solved the problem a different way (using combinations) and got the same answer. – Brett Frankel Mar 26 '12 at 2:47
1 Answer 1
Your argument is fine (as previously noted), and there's probably no significantly better approach to counting them.
If you want to double-check your result, here's some GAP code which can list all the possibilities.
for P in T do
 # where the last L is
 # where the first non-L consonant is
 if(b>a) then
and it found 95040, matching your result $4! \frac{11!}{7!\ 2!}$.
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Your Answer


Is Bengal Cat the Same as a Savannah?
In recent times:
Bengal and Savannah cats have gained quite a lot of popularity for they have a lot in common and tend to share the same attributes.
So, is the Bengal cat the same as a Savannah cat? No, it's not. Both being a product of crossbreeding a wild and a domestic cat do have some similarities, but they are certainly not the same. To an untrained eye, these two species might look the same, but for someone who knows better, this is not the case.
Both of these breeds while having a lot in common tend to have many differences too.
Common similarities between the Bengal and Savannah cat
To understand the differences that they have, it is better that we begin by taking a look at some of the similarities that account for this common misconception we have around.
1. Love for water
Both these breeds have a deep fascination with water which is very obvious.
Not only would they cause you less trouble during a bath but they in fact, like playing in the water too, unlike most of the other breeds that we know of.
2. Scratching
As is a common practice amongst all the breeds, these two like to scratch things a lot too.
From sofas to carpets, you can expect to find them scratching just about anything that they can get their hands on.
Hence, the reason, why investing in a scratch post is most rewarding with them.
3. Playful nature
They both are attention seekers and are very affectionate to the ones they love.
Their playful and affectionate nature is the key reason why they make such great domestic cats.
4. Coat
Not only their habits:
But even their appearances seem to have a lot in common too.
Bengal and Savannah cats have coats that are:
 - Tabby
 - Spotted
 - Low-maintenance
5. Genes
This may be the prime reason that accounts for all the confusion that surrounds these two breeds.
Since they both are made by crossbreeding a wild and a domestic cat, one often believes them to be the same. But this isn't so.
Keeping in view the few commonalities mentioned above, would you still go as far ahead as to call them both to be the same?
We hope not.
As similar as they might seem to a layman, they both are poles apart.
What makes the Bengal and Savannah cats different?
From the ancestral lineage to the health issues they both face, there are many differences that you would come across if you bring these two breeds home.
To help your way to it, we will now be taking a quick look at some of the many variances that are found in Bengal and Savannah cats.
1. Breeding
The factor that makes them look similar is the one that makes them have distinguishing personalities and characteristics.
It is true that they both are made by breeding a domestic cat with a wile feline but the types of cats that are used are not the same.
For the Bengal, a domestic cat is made to breed with an ALC, also known as Asian Leopard Cat. A Savannah, on the other hand, is a product of a domestic Persian and an African Serval Cat (ASC).
2. Sizes
It is for the difference in their ancestral lineage, that the size of these two cats varies too.
The Savanah being a product of larger cats can reach the size of a golden retriever occasionally which is around 56inches when measured from the nose to their tail.
Since the ASC has African heritage, they are not only bigger in terms of size but can also weight a lot too. This means that you can find Savannah cats that weigh as much as 30 pounds at times.
When compared to the Savannahs, the Bengals are smaller in size.
The ALCs are smaller cats and this is why the Bengals to end up being medium sized.
A female may range between 7 and 10 pounds while for a male the number can go up to 17 pounds commonly.
The Bengal cats keep growing till they reach an age of two. During this time, they reach the size of a common domestic cat.
3. Temperaments
As discussed above, since the origins of these two breeds vary, the temperaments they both exhibits tend to differ too.
Savannah being from the wilder and more ferocious breed manifests the same behavior and have often been considered to a dog. This breed, for its similarity to canines, is good at leash training and tends to get along well with the other pets that you might have around.
Bengal cats, on the other hand, are active and equally loyal; too but require smaller mental stimuli to remain happy.
Both these breeds are active, highly talkative and very friendly in nature.
The Bengal cat can be seen jumping and playing around for hours at a stretch and would just as suddenly drop everything it was doing to come and receive the overdue affection from is the owner.
The Bengal cat craves attention more than anything and would be all too happy to snuggle and lie around in the lap.
Savannahs are a little different in this regard. While they too are known for being very loving and affectionate, they are not such great snugglers. They are good at solving puzzles and can jump as high as 12ft if given the space to explore the skills that have been passed down to them from their ancestors.
4. Appearance
These two cats might look similar to an outsider but a little closer look and you will see that even their appearances are not the same.
While they do share certain similarities, they both look very different from each other. From the size to the kind of coat they have, each one has its own unique personality.
So moving on, what are some of the many ways that make these two breeds differ from each other?
Let us find that out.
Coat: While the coat is short-haired and low-maintenance for both, the difference lies in the details. Bengal cats have marbled or spotted pattern whereas the Savannahs have a pattern that is similar to the ASC with black spots accentuated by a silver, golden or smoke background.
Body shape: Even the body shape and physique they have is very much different from each other. Bengals are medium-sized and muscular while Savannahs are tall and lean.
Ears: Savannah cats have pointed upright ears whereas the ears of Bengal cars are small and round.
Eyes: Bengal cats are known for their "Mascara" eyes. Savannah has boomerang shaped eyes that are gold, green or brown in color with a tear stain that goes from the corner down to the nose.
5. Health
These both breeds like others that we have in the feline family suffer from health issues of their own.
While most of the problems they face are relatively similar, there are some concerns that lie more with one breed than the other.
For example, Bengal cats are more prone to the retinal degeneration and PK deficiency disease than the Savannahs.
With all this said, it would be safe to say that Bengal cats are certainly not the same as Savannahs cats.
In fact, from our discussion above, these two are more different with respect to their physical attributes than the genetic similarity they share.
So, what kind of pets do they make, you may ask?
Well, it all depends on what you are looking for.
Both were exceptionally good domestic cats are great to have around and would prove to be a good addition to your family.
Depending on what size of cat you are looking for, what attributes and temperaments you would want in it and how much space you have at home, the choice may vary.
Related Questions
How much space do these two breeds need? Owing to their size and temperaments, Savannah cats need more space than Bengal.
This is also essential for the reason that they are more prone to getting into trouble than the other breed in the discussion here.
Are the males of Bengal and Savannahs sterile too? Partly, Yes.
The males that are a part of the earlier generations of these two breeds are sterile as is seen with all the hybrid animals.
This, however, is not much of a concern in regard to their health and characteristics and shouldn't bother you much as well, until and unless you plan on breeding the felines you have at home.
How can you ensure better health of the litter being produced? By working on a healthier and better gene pool.
When using kittens for breeding, take a look at the ancestral lineage and go for the ones which do not have any direct relatives with the health concerns you are trying to avoid here.
However, this is just a safety measure you can take and in no way guarantees that the cat you have wouldn't have any health problems.
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text:
Sparse Approximate Inverses in a Finite Element Framework
My thesis describes a method for constructing sparse approximate inverses (SPAI) of blocks of matrices arising in the numerical solution of partial differential equations (PDEs), discretized using the finite element method (FEM). The matrices have a 2 by 2 block form, which in this case is obtained via refinement of the discretization mesh and classification of the nodes as coarse and fine. The SPAI matrix is assembled from small matrices, obtained by manipulation of the local stiffness matrices; a procedure that is fully parallelizable.
The framework can be used recursively on a sequence of meshes and is suitable for constructing of algebraic Multi-Level preconditioners of block-multiplicative type.
As an illustration, numerical results of using this method to solve the Poisson problem are presented, both serial and parallel. The serial test results show that this preconditioning method is robust with respect to problem size and to discontinuity of the coefficients of the PDEs, when the areas corresponding to different coefficients are aligned with the coarse mesh. The method is not fully robust to anisotropy. Parallel tests show that the performance of the method is independent of the number of processors used to solve the problem, and that the method is highly scalable with excellent parallelization properties.


text:
ABSTRACT: Throughout Amazonia, overfishing has decimated populations of fruit-eating fishes, especially the large-bodied characid, Colossoma macropomum. During lengthy annual floods, frugivorous fishes enter vast Amazonian floodplains, consume massive quantities of fallen fruits and egest viable seeds. Many tree and liana species are clearly specialized for icthyochory, and seed dispersal by fish may be crucial for the maintenance of Amazonian wetland forests. Unlike frugivorous mammals and birds, little is known about seed dispersal effectiveness of fishes. Extensive mobility of frugivorous fish could result in extremely effective, multi-directional, long-distance seed dispersal. Over three annual flood seasons, we tracked fine-scale movement patterns and habitat use of wild Colossoma, and seed retention in the digestive tracts of captive individuals. Our mechanistic model predicts that Colossoma disperses seeds extremely long distances to favourable habitats. Modelled mean dispersal distances of 337-552 m and maximum of 5495 m are among the longest ever reported. At least 5 per cent of seeds are predicted to disperse _PHONE_ m, farther than dispersal by almost all other frugivores reported in the literature. Additionally, seed dispersal distances increased with fish size, but overfishing has biased Colossoma populations to smaller individuals. Thus, overexploitation probably disrupts an ancient coevolutionary relationship between Colossoma and Amazonian plants.
Proceedings of the Royal Society B: Biological Sciences 03/2011; 278(1723):3329-35. · 5.41 Impact Factor


text:
Camera Calibration for Light Fields and Camera Arrays
Camera calibration, crucial for computer vision tasks, often relies on planar calibration targets to calibrate the camera parameters. This work explores a planar, fractal, self-identifying calibration pattern, which provides a high density of calibration points for a large range of magnification factors. An evaluation on ground truth data shows that the target provides very high accuracy over a wide range of conditions.
Fractal Calibration Target
The size of the calibration markers also play a key role in the accuracy of the localization. If too few calibration points are available per view, then calibration quality suffers due to over fitting. However, if the calibration markers become too small, it becomes impossible to properly detect them. As the optimal size depends on the camera magnification, it is not possible to create a pattern with a single optimal density.
Our solution is the adoption of a fractal scheme which operates on multiple scales of calibration points. This scheme allows to use features which are within some fixed bound of the maximum calibration point density for the given magnification, please see Figure. 1. In addition the target is self-identifying and quite robust under a range of imaging conditions.
 A Fractal Calibration Pattern for Improved Camera Calibration Hendrik Siedelmann, Maximilian Diebold, Marcel Gutsche, Hamza Aziz-Ahmad, Bernd Jähne
Forum Bildverarbeitung, 2016[paper]


text: Dublin, Ireland is scheduled to constructing its first metro in 2010, with a pair of tunnels connecting the city center to the airport. This study presents first-order predictions of the anticipated soil settlement and related building damage for a single structure on the route. The structure is a 19th century, stone church on glacial till situated almost directly above the shallowest portion of one of the tunnel crowns and immediately adjacent to a station box. To assess potential damage, a settlement trough is predicted based on another recent Dublin tunnel and the anticipated settlement is applied to the church. Damage predictions based on these freefield predictions are made and then revised as to the anticipated impact of the structure itself based on building stiffness, which significantly reduces the maximum differential settlement from 63mm to 36mm resulting in minimal predicted damage.


YALCOM – Yet Another LCOM Metric
This article is a spin-off piece from the paper "Do We Need Improved Code Quality Metrics?" by myself and Prof. Diomidis Spinellis.
Earlier, I wrote an article about issues with code quality metrics; in another article I presented how all the variants of LCOM metric misrepresent simple cases of class cohesion. In this article, I first summarize the deficiencies in the present set of LCOM variants (LCOM1, LCOM2, LCOM3, LCOM4, LCOM5) and then I present YALCOM that addresses the issues of existing LCOM variants.
Deficiencies in existing LCOM variants
 - LCOM1-4 take into account only the instance attributes of a class, ignoring any static attributes. Although the dynamic properties of a static attribute differ from the instance attributes (for instance, static attributes can be accessed without creating an object), these attributes are part of the class they reside in. In the context of a metric that measures the similarity among class members, their dynamic property is irrelevant. Therefore, ignoring static attributes while assessing cohesion is inappropriate.
 - The existing LCOM algorithms fail to distinguish the cases where the metric cannot be measured, from the perfectly cohesive cases, by always emitting the lowest metric value in the former cases. For instance, LCOM2 reports 0 not only when the type under measurement is completely cohesive, but also when the type is an interface and a utility class, i.e., a class with no attributes. Such an approach produces the illusion to the user that all cases with a metric value of zero are cohesive, while in reality, the algorithm was not provided with enough information to measure the metric and the algorithm fails to communicate this to the user.
 - Method invocations within a class show that methods are working together to achieve a goal and thus must be considered while computing LCOM. However, LCOM1-3 and LCOM5 do not consider method invocations to compute the metric.
 - Furthermore, the existing LCOM implementations focus on the common attribute access among methods within a class; however, they ignore common attribute access where the attribute is defined in a superclass. Classes are extensions of their superclasses, and it is very common to elevate data and method members to superclasses to avoid duplication among siblings. Hence, two methods that share attribute access or method invocation that is defined in a superclass contribute to cohesion and thus must be considered while computing the metric.
 - Lastly, Fenton and Pfleeger stated that a metric may follow a suitable measurement scale (such as nominal, ratio, and absolute) depending on the aspect being measured. LCOM1–4 measure cohesion on an absolute scale that may emit an arbitrary large number as the metric value making it almost impossible for the user to gain any insight from it. For instance, given that m is the number of methods of a class, the maximum value that LCOM2 may produce is (m * (m-1))/2, which could be a considerable number for large classes. To facilitate metric interpretation and comparison, bounded concept such as cohesion must be better represented by a normalized value.
The algorithm takes a type i.e., a class or an interface as an input. The algorithm returns -1 when the algorithm finds that the metric is not computable otherwise it returns a LCOM metric value [0, 1]. The metric is not computable when the number of methods is zero, or when the analyzed type is an interface. The algorithm creates a graph where the methods and attributes of the class are treated as vertices. Here, attributes from superclasses that are accessible from the class are also included. Relationships, i.e., field accesses and method invocations, among the methods and attributes, make the edges. For example, if a method m1 accesses attributes a1 and a2 as well as calls method m2, then the node corresponding to method m1 will have edges to nodes representing attributes a1 and a2 as well as to method m2. Once the graph is constructed for the input class, the algorithm finds the disconnected subgraphs of methods. If the number of disconnected subgraphs is one, then all the attributes and methods are connected to each other and hence the class is perfectly cohesive (and thus assigned as 0 as the metric value). If the number of disconnected subgraphs is more than one, it implies that there are many islands of functionality within the class and hence the class is not cohesive. Here, the higher number of such subgraphs implies poorer cohesion. We compute the metric by dividing the number of disconnected subgraphs by the number of methods in the class. Since the number of disconnected subgraphs cannot be more than the number of methods (when none of the methods is associated with rest of the methods in the class), the maximum value that the algorithm can produce is 1.
Validation and comparison
In order to establish whether the commonly used set of LCOM metrics sufficiently capture the cohesion aspect of abstractions, we handcrafted eight classes/interfaces representing different cases. They are designed to cover various common cases involving interplay of method calls, fields-their type (a class or an interface) and their accesses, and inheritance that impact class cohesion and may potentially reveal the deficiencies of the existing algorithms to compute LCOM.
The details of each of these cases as well as the performance of all the existing LCOM metrics and the proposed metric is presented in our paper. The source code that implement the considered variants of LCOM and YALCOM can be found on GitHub.
Author: Tushar
Tushar Sharma is a software engineering researcher, developer, and author. He is currently a Research Scientist at Siemens Corporate Technology, Charlotte, USA. The topics related to software design and architecture, refactoring, software quality (specifically code and design quality), and technical debt define his career interests. He earned PhD from Athens University of Economics and Business, Athens, Greece with specialization in software engineering in May 2019. Earlier, he obtained an MS in Computer Science from the Indian Institute of Technology-Madras, Chennai, India. His professional experience includes working with Siemens Research and Technology Center, Bangalore, India for more than seven years (2008-2015). He co-authored the book Refactoring for Software Design Smells: Managing Technical Debt and two Oracle Java certification books. He has founded and developed Designite which is a software design quality assessment tool used by many practitioners and researchers worldwide. He is an IEEE Senior Member.