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How Do You Lower Your A1C Level Fast?
Methods for lowering hemoglobin A1C levels include exercise, a low-fat diet, eating at regular times and following a prescribed treatment plan, explains Everyday Health. The speed at which A1C levels come down depends on the person. It may take some time to see a difference because A1C levels reflect blood sugar levels from the past two to three months.
A recommended diet for those looking to reduce their A1C levels includes non-starchy vegetables, whole grains, healthy fats, lean proteins and dairy, reports Everyday Health. High-fiber foods, such as fruits, vegetables and grains, are linked to improved blood sugar levels over time. The recommended amount of exercise involves 30 minutes of activity, five days a week. Individuals can do any activity they enjoy that gets them moving, such as biking or walking. Treatment plans may include medication and regularly checking blood sugar.
The A1C test measures how much glucose is attached to the hemoglobin proteins in blood, explains Everyday Health. Unlike blood glucose monitoring, a trained healthcare worker must perform this test at a medical office. Normal levels are below 5.7 percent. Between 5.7 percent and 6.4 percent is considered prediabetes, and 6.5 percent and above indicates diabetes. The test doesn't require the person to fast and may be done at any time of day.


.NET 3.0+
Simple Speech Synthesis
System.Speech.Synthesis Namespace
Sometimes you will need to output speech from your software. Common examples of software that requires speech are screen readers for the visually impaired and automated telephone systems.
In this article I will demonstrate the basics of speech synthesis using.NET framework classes.
The classes required for speech are found in the System.Speech.Synthesis namespace. To allow access to this namespace you must add a reference to System.Speech.dll to your project. To improve readability, add the following using directive:
using System.Speech.Synthesis;
Text to Speech
The simplest method for outputting speech is to use text to speech conversion. This allows a string containing the words to be spoken to be passed to a method of the SpeechSynthesizer class. The string is parsed and converted to a series of phonemes, each a small unit of sound. By playing the phonemes in quick succession, a human voice is simulated.
Plain Text to Speech
The first method that we will use to output speech is Speak. This can be used with a single string parameter containing the text to be spoken. The sound is played synchronously so commands following the call are not executed until the speech is completed. To demonstrate, execute the following code in a console application. You should notice that the text, "Finished", does not appear until the audio ceases.
var synth = new SpeechSynthesizer();
Asynchronous Speech
You can output speech asynchronously to allow processing to continue whilst the audio is played. To do so, use the SpeakAsync method. If you execute the following example you should see that the completion message appears before the audio finishes.
var synth = new SpeechSynthesizer();
11 December 2009


Sentence Examples
 - The old farm house had been wrapped in insulation and sided.
 - Unless the insulation is perfect, the potential recorded falls short of that at the spot where the radium is placed or the water jet breaks.
 - The potentials that have to be dealt with are often hundreds and sometimes thousands of volts, and insulation troubles are more serious than is generally appreciated.
How would you define insulation? Add your definition here.
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Plesiochronous digital hierarchy
From Wikipedia, the free encyclopedia
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The plesiochronous digital hierarchy (PDH) is a technology used in telecommunications networks to transport large quantities of data over digital transport equipment such as fibre optic and microwave radio systems.[1] The term plesiochronous is derived from Greek plēsios, meaning near, and chronos, time, and refers to the fact that PDH networks run in a state where different parts of the network are nearly, but not quite perfectly, synchronized.
Backbone transport networks replaced PDH networks with synchronous digital hierarchy (SDH) or synchronous optical networking (SONET) equipment over the ten years ending around the turn of the millennium (2000),[2] whose floating payloads relaxed the more stringent timing requirements of PDH network technology. The cost in North America was $4.5 billion in 1998 alone,[2] p. 171.
PDH allows transmission of data streams that are nominally running at the same rate, but allowing some variation on the speed around a nominal rate. By analogy, any two watches are nominally running at the same rate, clocking up 60 seconds every minute. However, there is no link between watches to guarantee that they run at exactly the same rate, and it is highly likely that one is running slightly faster than the other.
The data rate is controlled by a clock in the equipment generating the data. The rate is allowed to vary by ±50 ppm of 2048 kbit/s (according to ITU-T recommendation[3]). This means that different data streams can (and probably do) run at slightly different rates from one another.
In order to transport multiple data streams from one place to another over a common transmission medium, they are multiplexed in groups of four. Because each of the four data streams is not necessarily running at the same rate, some compensation has to be introduced. Typically the multiplexer takes the data from the 4 incoming 2.048 Mbit/s data streams and feeds each into a 2.112 Mbit/s stream via a buffer store leaving a series of fixed gaps in each frame.
The data rate is thus 2.112 Mbit/s x (number of bits in a frame – number of gaps)/(number of bits in a frame)
This is slightly greater than 2.048 Mbit/s + 50ppm. If an extra gap is added, this is slightly smaller than 2.048 Mbit/s – 50ppm. Thus on average the data rate can be made exactly equal to the incoming rate by adding a gap in some frames and not others. This extra gap is in a fixed place in the frame and is referred to as the "stuffable bit". If it does not contain data (i.e. it's a gap) it is "stuffed". The data from the 4 data streams in now contained in 4 data streams of 2.112 Mbit/s which are synchronous and can easily be multiplexed to give a single stream of 8.448 Mbit/s by taking 1 bit from stream #1, followed by 1 bit from stream #2, then #3, then #4 etc. Some of the fixed gaps accommodate a synchronisation word which allows the demultiplexer to identify the start of each frame and others contain control bits for each stream which say whether or not the stuffable bit is stuffed or not (i.e. contains data or not). The process can then be reversed by the demultiplexer and 4 data streams produced with exactly the same bit rate as previous. The timing irregularity is ironed out using a phase locked loop.
This scheme does not allow the addition of a stuffed bit as soon as it is required because the stuffable bit is in a fixed point in the frame so it is necessary to wait until the stuffable bit time slot. This wait results in "waiting time jitter" which can be arbitrarily low in frequency (i.e. down to zero) so cannot be entirely eliminated by the filtering effects of the phase lock loop. The worst possible stuffing ratio would be 1 frame in 2 as this gives a theoretical 0.5 bit of jitter so the stuffing ratio is carefully chosen to give theoretical minimum jitter. In a practical system however, the actual decision to stuff or not may be made by comparing the read address and write address of the input buffer store so the position in the frame when the decision is made varies and adds a second variable dependent on the length of the store.
The process is sometimes called "pulse justification" because "justification" in printing is adding gaps so that each line takes up a full column width. It is believed that this term was preferred because "...... stuffing stuffable bits", and "waiting time jitter is the jitter you get while waiting to stuff a stuffable bit", though technically correct, does sound like a pleonasm!
Similar techniques are used to combine four × 8 Mbit/s together, plus bit stuffing and frame alignment, giving 34 Mbit/s. Four × 34 Mbit/s, gives 140. Four × 140 gives 565.
Independent clocks[edit]
In telecommunications networks, independent clocks are free-running precision clocks located at the nodes which are used for synchronization.
Variable storage buffers, installed to accommodate variations in transmission delay between nodes, are made large enough to accommodate small time (phase) departures among the nodal clocks that control transmission. Traffic may occasionally be interrupted to allow the buffers to be emptied of some or all of their stored data.[4]
See also[edit]
 1. ^ Valdar, Andy (2006). Understanding Telecommunications Networks. IET. p. 78. ISBN 9780863413629.
 2. ^ a b Cavendish, Dirceu (June 2000). "Evolution of Optical Transport Technologies: From SONET/SDH to WDM". IEEE Communications Magazine. 38 (6): 164–172. doi:10.1109/35.846090.
 3. ^ tsbmail. "G.703 : Physical/electrical characteristics of hierarchical digital interfaces". Retrieved 2016-03-06.


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In German, two-part composite nouns (Schul·lehrer, Schlüsel·loch, Elektronen·mikroskop, Sonnen·wende, etc.) are abundant, but composite nouns consisting of three or more parts are not at all uncommon: Grund·schul·lehrer, Schlüsel·loch·chirurgie, Raster·elektronen·mikroskop, Winter·sonnen·wende·punkt.
In English, the joining of two nouns into one (e.g. school·teacher, key·hole) also happens, but it is not as common as in German (e.g. electron microscope, not electron·microscope), and, as far as I can tell, it is limited exclusively to two-part composites (one never sees composites like elementary·school·teacher).
But, if one considers only the spoken language, then there's a close syntactical similarity between, on the one hand, German composite nouns like Raster·elektronen·mikroskop and Grund·schul·lehrer, and on the other, English "nominal" collocations like scanning electron microscope and elementary school teacher.
Now, assuming this correspondence between German composite nouns and English nominal collocations, one can begin to formulate questions about the relative frequencies of such entities in the respective languages.
One such question that interests me is whether composite nouns of three or more parts (for which I'll use the shorthand 3+-compounds) are more common in German than nominal collocations of three or more words (or 3+-collocations, for short) are in English. I suspect that the answer is yes, and would appreciate pointers to any systematic research on this question.
(I realize that the description above oversimplifies greatly, glossing over many complications that would get in the way of a systematic study. For example, it is not always clear how to count the number of parts in a composite word. Is it Umwelt·schutz or Um·welt·schutz? Is it Infrarot·strahlung or Infra·rot·strahlung? There's also the question of whether the frequencies of German 3+-compounds and English 3+-collocations should be normalized, respectively, by the frequencies of German 2-compounds and their counterparts in English (i.e. both 2-compounds and 2-collocations taken together). Dealing with such complications, however, is part of what this sort of research typically entails.)

source: HuggingFaceFW/fineweb-edu


debated topic. There are lots of tourism and fishing jobs at risk as well as this being a relatively new area of research, where the costs and benefits of MPA allocation are often unknown. Generally the public know very little about the marine environment; in particular marine ecology and policy processes (Compas et al 2007).
Recreational fishers have concerns over their rights in MPA allocation.
Compas, et al. (2007) looked at how MPA's were conveyed in South Australian media from 1996 – 2007. At this time 19 MPA's were proposed within South Australian waters. They identified that the public gets most of their information about policies and environmental protection from written media i.e. newspapers. Therefore a range of newspaper articles were reviewed for their content during this period.
Their studies concluded that well-informed and knowledgeable members of the public are more likely to support environmental causes. Of the newspaper articles that were reviewed, most of the reporting concentrated on opposing stakeholders and opinions instead of information on the significance of marine ecology or MPA establishment. 'These information gaps have left the public poorly informed, and therefore, there is unlikely to be significant pressure to overcome the continued delays in the establishment process' (Compas et al 2007, 1).
To date, these marine parks have still not all been implemented in South Australia. What tactics or approaches do you think could be used to try and inform the public about the importance of protecting their marine resource? How much or little do you know yourself about MPAs and where would you go to source your information?
Compas, E, Clarke, B, Cutler, C, and Daish, K (2007) Murky Waters: Media reporting of marine protected areas in South Australia. Marine Policy. vol. 31, no. 6, pp. 691 – 697.
Thinking before drinking
Drinking alcohol has become a social norm in probably most countries, and has resulted in various outcomes – for example, crime, accidents, health problems etc; none of which are positive.
In the short span of 2.5 years of studying in Australia, I (and friends close to my heart) have experienced so many situations which resulted from drunk people just losing control – basically the doing of influence of excessive alcohol intake. Just to name a few, we've have had drunkards brandishing knives at us, friends getting punched or glassed randomly while walking home, passersby throwing bricks and stones at us, and one even getting raped and pregnant.
It seems all too familiar as there are constant reports of drunken acts all the time, and it also seems that familiarity has nullified the emotional aspect that was once attached to these outcomes. Is it really okay? Is it really acceptable?
The reality is that these things were serious and are serious, and have either an immediate effect or a long-term effect, or both – which is essentially an accumulated effect.
This brings us right back to the very beginning – why is alcohol being promoted so much when it has such devastating effects? Is it because of the huge profit that it brings in? The other question to ponder is – if alcohol is so popular, then what is it about alcohol marketing that is causing it to be so successfully promoted?
The goal of the article by Meier.P was to encourage a rethink of market research priorities in relation to alcohol marketing.
Many researchers and politicians concentrate on the potential harm to young people, and assume that alcohol marketing carries risks for children because they are perceived as cognitively incapable in distinguishing the advert portrayed from real-life experiences. It is true that promotion of alcohol to or in the presence of younger target audience will result in increasing the odds of them having a first trial, but this thinking perhaps need some reconsideration as most alcohol marketing are targeted at existing alcohol consumers. When an alcoholic product is being promoted to consumers, it is either presented to them during drinking experiences, or in between drinking experiences.
When alcohol is being marketed, it always almost seems to have an "optimistic frame", pointing toward fun, fun and more fun. But with these advertisements, do they display any communication of the negative effects that may follow? If ghastly images of lung/throat cancer can be printed onto cigarette packs to warn consumers (visually) of the health impacts they may face, should alcohol bottles have printed warnings of excessive alcohol intake?
This whole alcohol topic is huge and can be and will be discussed so much more in the future, so it's a good time to stop and think about it now.
Reference: Meier, P. 2011. Alcohol marketing research: the need for a new agenda. Addiction, 106, 466-471
Effective? Valuable? The Dilemma of Citizen-science Projects
"I have been a fan of citizen science for many years, but I do not think the citizen science movement has had the educational impact that it could," said Daniel C. Edelson, the Vice President for Education of National Geographic Society.
Dominique Brossard, Bruce Lewenstein and Rick Bonney discussed the evaluation of an informal science education project, The Birdhouse Network (TBN). They used a pre-test before participants received the educational material and protocols and a post-test at the end of the field season, to figure out:
1) Would participation in the TBN result in positive effects on the knowledge of bird biology among adult participants?
2) Would it result in increased knowledge of the understanding of the nature of scientific inquiry? and
3) Would it result in positive effects on attitudes toward science and the environment?
According to the result, the increase of participants' knowledge of bird biology was comparatively obvious. However, their understanding of scientific process could not be statistically detected, and the attitude toward science was essentially unchanged. Therefore, by participating in a citizen-science program adults will not necessarily improve their understanding of scientific process, nor change their attitude toward science.
By the time TBN was done, citizen science had already lasted for more than 20 years. So such a result may sound a little bit negative, but personally, I think that due to the new technology we have today, citizen science project can be better built. But before we start to think how we can make the citizen-science projects more effective, there is one more question: What are the objectives of citizen-science?
Due to the large quantities of participants, citizen science projects are often used to help researchers to analyse gathered data, or gather data for researchers, such as ClimateWatch. It cannot be overstated that citizen science projects are more than collecting data, but it can be a dialogue between participants and professional scientists, and more than scientific knowledge can be involved.
Entertaining probably is the first expectation of most participants. People like having fun, and as we all know that learning with entertainment is much more effective. But it's not enough, many citizen-science projects are time-consuming. People expect get some rewards for donating their time, and they deserve it. Educating is well involved in most citizen science projects, but most of them are specifically narrowed down to the subjects relating to the projects, and that make it too pragmatic; Feedback can help the educational result as well. The most difficult part may be to motivate participants, but that can be achieved by some ways, including making it easy to learn, easy to do, offer excitement, even provide challenge.
But the question is: Does getting participants' attitudes changed match the objectives of citizen-science projects? Apparently it's not necessarily true. So do you still think it's valuable to change their attitudes?
citizen science project, International Journal of Science Education, 27: 9, 1099 – 1121.
Cooper, C. B., Dickinson, J., Kelling, S., Phillips, T., Rosenberg, K. V., Shirk, J., & Bonney, R. (2009). Citizen Science: A Developing Tool for Expanding Science Knowledge and Scientific Literacy. Bioscience59(11), 977-984
Edelson, D. C., (2012). Unlocking the Educational Potential of Citizen Science. Esri News. Retrieved from here


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Last week's column dealt with the diary of Moravian missionary Theodor Schulz who traveled to Bethlehem and other nearby Moravian settlements in 1799. As noted last week, personal documents such as diaries, letters, journals, business records, and art work created by people living during the old times are the most trustworthy historical sources.
The Theodor Schulz Diary is presently part of the Henry Stauffer Borneman Pennsylvania German collection at the Free Library of Philadelphia. A stellar collection, it was previously owned by Henry Stauffer Borneman, Esq. (_PHONE_). Borneman had an expert eye as he selected rare examples of Pennsylvania German Fraktur, imprints, and manuscripts. After his death in 1955, the Free Library of Philadelphia was fortunate enough to purchase eighty-five years worth of carefully chosen artifacts. It's also interesting to note that Borneman was co-founder of the Temple University School of Law.
According to Borneman family historian Ruth Borneman, Henry Stauffer Borneman was born in Allentown, the son of pharmacist and dentist Joseph Borneman. Dr. Borneman moved his family to Clayton, near Bally, in 1872. He then became the proprietor of Eagle Drug Store in Boyertown.
It has been said that the Bornemans in this area are all descendents of Daniel Borneman who emigrated in 1721. He bought land and cleared a farm along what became Knight Road in Upper Hanover Township. Daniel's son Christian moved to Limerick Township and his son John, a stone mason who settled in Boyertown, was the father of Joseph.
Historian and researcher Del-Louise Moyer of the Free Library of Philadelphia is transcribing and translating Schulz's Diary for a forthcoming publication. It is written in German script, a cursive handwriting that replaced Gothic calligraphy at the beginning of the sixteenth century. Under a Save America's Treasures grant from the National endowment for the Humanities, the Diary is being conserved by the Conservation Center for Art & Historic Artifacts in Philadelphia.
During his four months in Pennsylvania, Theodor Schulz recorded what personally interested him, and reflected on matters close to his heart: the contemporary landscape, customs of the land, architecture, crops, commerce, weather and the daily spiritual life of the Moravian communities he visited. Selections continued from last week:
"2 September, Christiansbrunn (Christian's Springs) and Gnadenthal (Gracedale). One finds fruit and peach trees at both locations. The grain here is usually threshed using horses. The barns are built on the hillsides, so that on one side, built into the foundation, are entrances for the animals to their stalls, and on the other side, above the stalls, is the threshing floor, across which one can drive. The way milk is kept here is also quite wonderful. By means of small water locks, clear flowing spring water can be fed at higher or lower levels into stone spring houses. The milk pans stand in this cold flowing water (Spring water has a constant temperature in southeastern Pennsylvania of 50-55 degrees F.)…
"13 September, Br. Reichel showed us around the place, and we were especially impressed with Br. Henry's rifle manufactory, the lovely hatmaking workshop, and the metal workshop. In the afternoon we went to Br. Henry's mill in Plainfield Township, about three miles distant from Nazareth, where his rifles are bored, smoothed, and polished. It was a superb walk northwards through pleasant chestnut and nut trees, and beautiful plantations—four miles from the Blue Mountains, which formed a magnificent vista. Here we tasted the wild, large wine grapes known as fox grapes, which, although very large in size—almost the size of plums—and therefore quite noticeable to us, were not to our liking. There is another type of wild wine grape in Pennsylvania, which is smaller than normal, but tastes very good….
"21 September, …First we traversed the Lehigh river and its islands; then through the small Jordan Creek at Trexlers. We breakfasted on the Little Lehigh and Large Spring. After that we went through the village of Cootstown (Kutztown), then the city of Reading. The latter lies in a charming area on a plain between rocky mountains, not far from the Schuylkill, over which we took a ferry. We travelled through the mountains on very stony paths, and several creeks. On the way we encountered a lot of undergrowth and ground acorns—thus the saying that in America the swine eat the acorns from the trees. Then we went through a miserable little place called Adamstown, which probably got its name from the red earth, i.e. Adam's earth. We came to Reamstown at noon, and afterwards past Ephrata where the German Seventh-Day Baptists have their colony and cloister. …
To be continued…
Schulz served as a Moravian missionary to Surinam, but returned to Bethlehem in 1806 due to his wife's deteriorating health. He went on to serve as pastor to Moravian congregations.
Preservation of the Free Library of Philadelphia's Pennsylvania German Manuscript Collection has been made possible in part by a major grant from the National Endowment for the Humanities: because democracy demands wisdom. Any views, findings, conclusions, or recommendations expressed in this article do not necessarily represent those of the National Endowment for the Humanities.
Credits: Transcription/Translation: Del-Louise Moyer, Theodore Schulz Diary (forthcoming publication) Courtesy: Henry Borneman Pennsylvania German collection, Free Library of Philadelphia.


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The Math Learning Center is committed to offering free tools, materials, and other programs in support of our mission to inspire and enable individuals to discover and develop their mathematical confidence and ability.
In a remote environment, how can Bridges educators provide appropriate scaffolds and be responsive to student thinking? Sharing MLC apps with students can be a powerful approach, particularly when working with students in an asynchronous setting.
What does it mean to share with an MLC app? Put simply, Bridges educators can build a "saved state" task that they share with their students by way of an 8-character share code or link. After completing the task, students can share their thinking with their teachers and classmates.
UPDATE (10/1/20): Grade 4 and Grade 5 replays have been added below.
Grade-level webinars began last week when we took a deep dive into Bridges in Mathematics Unit 2 for Kindergarten, Grade 1, Grade 2, Grade 3, Grade 4, and Grade 5. For your convenience and to facilitate sharing with your peers, we've included the replays for each of those grade levels below. Since we cover resources that were created to support Bridges educators during the 2020-21 school year, you may find the definitions and links on this reference document helpful.
This week The Math Learning Center began what will become a regular series of support webinars for Bridges Educators in grades K–5. We will be hosting these webinars throughout the 2020–2021 school year. The intent is to provide teachers support to explore the resources that MLC has created and guidance for how they might use them to support students. The grade-level support webinars will be one hour long, with 45 minutes devoted to unpacking the upcoming unit of study and 15 minutes reserved for addressing frequently asked questions.
In this recorded session from the Zoom Academy, Bridges educators Kimberly Kelly and Mary Duden shared strategies, activities, and technologies for engaging elementary students in synchronous learning. The Bridges in Mathematics curriculum was designed for hands-on learning and student discourse. Moving that approach online required creative use of technology, modified materials, and professional development.
Wildfires have created hazardous air quality throughout much of Oregon, including our warehouse location in Salem. We shut down operations last Thursday afternoon and will remain closed until conditions improve enough that our team can safely return.
Our customer service team is working remotely and will continue to process orders and respond to inquiries. We appreciate your patience as we work
Whether you are returning to school in a virtual, in-person, or blended learning environment, flexibility will be as essential as pencils and paper this school year. The all-new Math at Home website offers the flexibility you need to present your students with rich activities to engage in deep mathematical thinking, no matter where their learning happens.

source: openbmb/Ultra-FineWeb


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In this tutorial, we'll show how to find all the ways to win a game of tic-tac-toe.
2. Problem Statement
Even though we're dealing with a game that we can play using an adversarial search algorithm such as minimax or Monte Carlo Tree Search, we should note that the problem we're solving now isn't that of game playing. Instead of winning a single game against an actual opponent, we want to find all the states of the tic-tac-toe grid that represent a victory for player or player.
Another thing we should note is that this also isn't a problem we can classify as a traditional search for the best solution because we're not interested in the shortest sequence of winning moves. Instead, we consider all the victories equal, no matter the number of moves, and want to discover them all.
3. The Brute-Force Solution
The simplest way is to iterate over all the states of tic-tac-toe and return only those in which a player wins.
To do so, we first have to define a tic-tac-toe state. Since we play it on a grid, and each cell can be either blank or marked with or, we can define the states of the game as matrices. For example:
There are states the grid can be in, but not all of them are legal. Since players and alternate, the difference of the number of s and s on the grid at any point in the game can be at most 1. For instance, the following state isn't legal because made three moves while made only one.
3.2. States and Matches
Each state corresponds to several matches. If the player occupies cells, and fills cells, then there are sequences of moves that lead to that state. For example, these two sequences finish in the same state:
There are move sequences that end the same way.
3.3. Win States
Let's define a test to check if a legal grid state represents a victory for player.
The first thing that we should check is if contains a row, a column, or a diagonal comprised of all s. However, although this test would capture all the grid states in which wins, it would produce a significant number of false victories. For instance, the following grid state passes this test for player :
even though it's not possible to encounter it in an actual game! As soon as filled the middle row, the game stopped, and couldn't mark its third cell, so one is illegal.
Therefore, if player wins, it will have one cell more than player. But, if player wins, it will always have the same number of cells as player. That's because has the first move, and the game stops after the winner makes its last move.
For the same reason, can win only in the odd turn, while can win only in the even turn. If the number of filled cells is even, and both and qualify for a win, then we know that the state is illegal. Since wins in the odd turn, the game would have ended before would get to connect its three cells.
So, this is the pseudocode to check if player has won:
Finally, we formulate our brute-force approach as follows:
Both the space and time complexities of our algorithm depend on the size of the search space. We calculated that there were states in total. Modern computers can easily store all of them in the main memory. So it's reasonable to expect that it won't take much time to run this algorithm, depending on the actual hardware used and other jobs our CPUs are executing concurrently.
That's why a brute-force approach is justified in this case. Since the problem is tractable, a simple algorithm without complex logic can handle it.
4. Generalizations of Tic-Tac-Toe
However, generalizations of tic-tac-toe require a more sophisticated approach.
In them,n,k-game, we play tic-tac-toe on a grid. The winner is the player that first connects cells horizontally, vertically, or diagonally. An grid can have states. For example, the board has states. So, even for small values of and, there are too many states for a brute-force solution to be efficient.
Similar holds for the three-dimensional tic-tac-toe usually played in a cube of cells.
To find all the win states in these forms of tic-tac-toe, we'd have to use a more efficient constraint-satisfaction technique. We'd define constraints on the grid cells that win states fulfill and then construct the state cell by cell. If we realize that a state is illegal or infer that no player can win, then we backtrack and change the assignment of one of the cells we previously left blank or filled with or. Once we find a win state, we record it, backtrack, and continue the search.
In this article, we showed how to find all the tic-tac-toe grids that represent a win. Even though a simple brute-force algorithm proved sufficient to handle the standard game, the generalizations of tic-tac-toe to three dimensions and larger grids require a more efficient approach.


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Taking Reading Performance
to the Next Level
K-D Reading Acceleration Program significantly improves reading performance by teaching children the physical act of reading
What is K-D Reading Acceleration Program?
Accurate and efficient eye movements are essential to develop strong and confident readers. When younger children are learning how to read, they have imprecise eye movements – in which eyes must reread text – resulting in slower performance and reading rates. Eye movements are learned motor skills that, like other complex motor skills, take practice and develop with age.
The King-Devick Reading Acceleration Program (K-D RAP), a simple web-based program, helps children learn how to move their eyes effectively by practicing the physical act of reading.
Over 90% of all children enrolled in K-D RAP significantly improved reading fluency and comprehension in as little as six weeks
"Kelsey practiced with RAP often which helped her improve her reading fluency. She is excited to be a faster reader and is getting better each day."
"I like this because I get to see my progress. My highest practice speed has been 50 npm. I am not moving my head as much while I read!"
"Sabrina is able to follow lines without using her finger. She is able to read the right line without jumping around after practicing with the Reading Acceleration Program. Sabrina loved doing RAP, and she continues to practice beyond the initial 6 weeks!"
"Aaliyah has been practicing at home for 3 weeks and enjoys RAP way more than her school work!"
Why K-D RAP?
Why Teaching Children the Physical Act of Reading is Important
According to the NAEP, 63% of 4th graders are NOT proficient readers
By the end of 3rd grade, children transition from learning to read to reading to learn
K-D RAP is Simple and Easy to
Navigate for All Users
When children use K-D RAP, they are tasked to read aloud dynamically presented number targets as quickly and accurately as possible. Speed settings are easily adjusted and increased with ongoing practice.


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Jan. 14, 2013 Salmon runs are notoriously variable: strong one year, and weak the next. New research shows that the same may be true from one century to the next.
Scientists in the past 20 years have recognized that salmon stocks vary not only year to year, but also on decades-long time cycles. One example is the 30-year to 80-year booms and busts in salmon runs in Alaska and on the West Coast driven by the climate pattern known as the Pacific Decadal Oscillation.
Now work led by University of Washington researchers reveals those decadal cycles may overlay even more important, centuries-long conditions, or regimes, that influence fish productivity. Cycles lasting up to 200 years were found while examining 500-year records of salmon abundance in Southwest Alaska. Natural variations in the abundance of spawning salmon are as large those due to human harvest.
"We've been able to reconstruct what salmon runs looked like before the start of commercial fishing. But rather than finding a flat baseline -- some sort of long-term average run size -- we've found that salmon runs fluctuated hugely, even before commercial fishing started. That these strong or weak periods could persist for sometimes hundreds of years means we need to reconsider what we think of as 'normal' for salmon stocks," said Lauren Rogers, who did this work while earning her doctorate in aquatic and fishery sciences at the UW and is now a post-doctoral researcher with the University of Oslo, Norway.
Rogers is the lead author of a paper on the findings in the Jan. 14 online early edition of the Proceedings of the National Academy of Sciences.
"Surprisingly, salmon populations in the same regions do not all show the same changes through time. It is clear that the salmon returning to different rivers march to the beat of a different -- slow -- drummer," said Daniel Schindler, UW professor of aquatic and fishery sciences and co-author of the paper.
"The implications for management are profound," Schindler said. "While it is convenient to assume that ecosystems have a constant static capacity for producing fish, or any natural resource, our data demonstrate clearly that capacity is anything but stationary. Thus, management must be ready to reduce harvesting when ecosystems become unexpectedly less productive and allow increased harvesting when ecosystems shift to more productive regimes.
"Management should also allow, and probably even encourage, fishers to move among rivers to exploit salmon populations that are particularly productive. It is not realistic to assume that all rivers in a region will perform equally well or poorly all the time," he said.
The researchers examined sediment cores collected from 20 sockeye nursery lakes within 16 major watersheds in southwestern Alaska, including those of Bristol Bay. The scientists homed in on the isotopic signature of nitrogen that salmon accumulate in the ocean and leave behind in lake sediments when they die: When there was a lot of such nitrogen in the sediments, it meant returning runs during that time period were abundant; when there was little, runs had declined.
Climate is not the only reason for long-term changes in salmon abundance. Changes in food webs, diseases or other factors might be involved; however, at present, there are no clear explanations for the factors that cause the long-term variability observed in this study.
Most, but not all, of the lakes examined showed declines in the kind of nitrogen the scientists were tracking beginning around 1900, once commercial fisheries had developed. However, earlier fluctuations showed that natural processes had at times reduced salmon densities as much as recent commercial fisheries, the co-authors said.
"We expected to detect a signal of commercial fishing -- fisheries remove a lot of the salmon, and thus salmon nitrogen, that would have otherwise ended up in the sediments. But we were surprised to find that previous returns of salmon to rivers varied just as dramatically," Rogers said.
As the paper said, "Interestingly these same fluctuations also highlight that salmon stocks have the capacity to rebuild naturally following prolonged periods with low densities, suggesting a strong resilience of salmon to natural and anthropogenic depletion processes. Indeed, total salmon production (catch plus escapements) has been relatively high in recent years for most sockeye salmon stocks in southwestern Alaska, despite a century of intense harvesting."
Other co-authors are Peter Lisi and Gordon Holtgrieve with the UW, Peter Leavitt and Lynda Bunting with University of Regina, Canada, Bruce Finney with Idaho State University, Daniel Selbie with Fisheries and Oceans Canada, Canada, Guangjie Chen with Yunnan Normal University, China, Irene Gregory-Eaves with McGill University, Canada, and Mark Lisac and Patrick Walsh with Togiak National Wildlife Refuge, Alaska.
Funding was provided by the Gordon and Betty Moore Foundation, the National Science Foundation, the U.S. Fish and Wildlife Service and the Natural Sciences and Engineering Research Council of Canada.
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text:
Message from the Parkside Principal
Welcome to Parkside School, where we build positive relationships and maintain high levels of academic rigor to support the social, intellectual, emotional and physical needs of all students. Students and staff at Parkside School are known for our friendliness, enthusiasm and hard work. Parent involvement is crucial in the success of our students, and we strive to build relationships and maintain regular communication with parents. Parkside School includes elementary grades 4 and 5, as well as, middle school grades 6, 7 and 8. In the elementary grades, teachers prepare students for the transition to middle school, while middle school teachers prepare students for the transition to high school. This is a time for students to explore their interests and begin career planning so they will be successful inside and outside of school.
-Deb Premo, Parkside School Principal
-Jim Rauchle, Parkside School Assistant Principal


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2 Working with family groups and networks
In this section you will study the impacts of social work intervention. You are asked to consider various aspects of applied social work practice with individuals and their personal networks. Children and families social workers are often engaged in finding placements and 'new' families for looked after children. Workers in adult services are also concerned with transitions between home, hospital and care homes. Social work interventions can have significant impact on service users and their kin as well as on their friendships and wider community supports. All these loyalties are very significant in people's lives, therefore interventions should take account of them.
The importance of communities and long-term friendships to many adults should not be underestimated. This is especially the case with many adult service users who develop strong friendships built on years of shared experiences. They may also have community support networks which complement or replace relatives and friends who live at a distance. Children's friendships are very important too, and offer vital peer support and a sense of not being alone.
It can be argued that working with several individuals at once enables a more effective exchange of information and perspective. In this section, you are asked to think about the dynamics of working with families as groups. In social work practice, this could happen in many ways: for example, with adoptive families, foster families, families by choice and close networks, biological families, single adults and their networks, and couples.
Working with families as a whole (or with individuals and their social support networks) to enable them towards increased wellbeing remains part of the social work role, whether it comes about through planning meetings, case conferences or assessments and longer-term involvement.


Support our community in a meaningful way
Leave a legacy to be remembered by future generations
Take advantage of numerous tax and financial benefits
Learn About Wills and Bequests
What are the benefits of making a bequest?
 1. You leave a lasting legacy to be remembered
 2. You lessen the burden of taxes on your family
 3. You may receive estate tax savings
How can I learn more?
How do I make a bequest?
A bequest is one of the easiest gifts to make. With the help of an advisor, you can include language in your will or trust specifying a gift be made to family, friends or Saint Elizabeth Community as part of your estate plan.
What are my options?
A bequest can be made in several ways:
 1. You can gift a specific dollar amount or asset
 2. You can gift a percentage of your estate
 4. You can make a beneficiary designation of certain assets
How do I get started?


text:
Review: Speed Breeding a Ray of hope for the future generation in terms of food security
European Journal of Molecular & Clinical Medicine,
2021, Volume 8, Issue 2, Pages 2653-2658
AbstractSpeed breeding has revolutionized whole of the world in today's era. The first ever speed breeding procedure was developed through an inspiration from NASA which was adopted by the University of Queensland scientists. Speed breeding is a protocol which enables plant breeders to enhance the crop production changing the temperature and light duration and intensity to enhance the growth of the plant. It is using artificial source of light that too continuously which triggersthe photosynthesis process results in the growth and the process of reproduction comes very early as compared to normal timing. The researches show that by Speed breeding techniques we can grow approximately 6 generations of wheat, chickpea & barley and around 4 generations of canola plants in a single year. This will help us to meet the demands of the growing population of future. This can be accomplished through various technologies such as genotyping, MAS, highthroughput phenotyping; gene editing, genomic selection,re-domestication which can be integrated with speed breeding to enable plant breeders to keep up with a evolving climate and ever-increasing human population.
- Article View: 63
- PDF Download: 305


text:
Human beings are warm blooded animals. The entire body and its organ systems are designed to operate efficiently at a temperature around 98 degrees Fahrenheit. There are small variations that take place throughout the day that raise or lower the body temperature marginally. However, these variations are usually within 1 degree. The body uses an extensive mechanism for thermoregulation. Heat is generated in the body during the process of metabolism. This process uses food and oxygen to produce energy in a chemical reaction. Heat is one of the by-products of the process. Heat produced during metabolism is transported around the body in the blood. When the body becomes cold, the blood vessels constrict to allow the heat to be maintained in the core of the body. When the body is warm, blood vessels expand, allowing more blood to flow to the extremities of the body. This allows for the dissipation of heat through the skin surface. Sweating is a way of accelerating the heat dissipation process as this causes evaporation which causes cooling. The body has various organs that send information about heat or cold to the brain which then controls the temperature using endocrine glands.
Low body temperature after surgery is a condition that affects many patients. Surgery is an invasive process that can have a shock-effect on the body of the patient. In any case, an individual at rest will have a slightly lower body temperature than one who is awake. Coupled with this, most surgery rooms are air conditioned and tend to be very cold. Surgery also causes blood loss. In some cases, surgery is performed to remove some organ or organ system from the body. Therefore, low body temperature after surgery is caused by a combination of these factors as the body struggles to maintain its temperature levels while healing the wounds of surgery. Furthermore, low body temperature after surgery is related to medication that is given to the individual before and during the procedure. Add to this, the lack of activity on an operating table means that there is slow metabolism and low heat generation in the body.
Low body temperature after surgical treatment means that the patient needs to be properly covered with heated blankets so that the temperature is maintained in the hours after surgery. Low body temperature after surgery can cause complications if it is not treated properly. Within a few hours, the individual usually regains the ability to regulate his or her temperature as the effects of the anesthesia wear off.More articles from the Health Articles Category


text:
(a) The commission shall maintain a system by which accurate statistics regarding the disposition of all manufactured homes by licensees may be obtained.
(b) The commission shall require that each licensee in this state maintain adequate records so as to ascertain all of the following information:
(1) The total number of manufactured homes manufactured.
(2) The total number of manufactured homes delivered to dealers within and without the state.
(3) The total number of manufactured homes sold to individuals within and without the state, including name, address, and county.
(4) Specific information about each manufactured home, including serial number, manufacturer's name, model name or number, or both, and size unit.


Changing X-axis labels in charts.
Table of Contents
Sometimes changes are called for in the design of the charts.
There are certain features of charts that are constant. For example, the number of characters for the labels on the x-axis. If you would like more or less or different characters displayed, the following steps will assist you with this.
 1. Generate a diagram for which a chart is to be made from.
 2. Click on the chart button to the left of the diagram.
 3. Click once on the chart you wish to change so it is highlighted.
 4. Select the "Copy" button to the right.
 It is our recommendation that a copy of the original chart is made, so the original features of the chart are maintained.
 5. Now click once on the new chart you just created, so it is highlighted.
 6. Select the "Label" button to the right.
 7. Hightlight the data on the left that needs to be changed. The top right box is what is displayed on the charts. This is where changes should be made.
 8. Once all changes are made, select "Done".
 9. Now double click on the new chart to see changes made.
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First time a vertebrate has been seen to evade predators by smelling like its habitat
Tane Sinclair-Taylor
The filefish appears to have come up with a clever way to elude its predators
A reef fish can hide from predators by adopting the smell of the coral it eats, according to researchers in Australia. This is the first time that chemical crypsis – the ability of an organism to avoid detection by using odour-based camouflage – has been observed in vertebrates.
It has been known for centuries that animals can visually blend into their environment to hide from predators. But given that vertebrates rely on more than just their sight to find prey, researchers have questioned whether other types of camouflage exist.
'With the importance of smell for a lot of animals, it makes sense to be chemically camouflaged but there's very little evidence for it,' says study author Rohan Brooker formerly from James Cook University, Australia. He goes on to explain that until now caterpillars were the only creature discovered that hid themselves from predators in this way. The caterpillars eat their plant habitat, assume their smell by absorbing certain chemicals in the plant, and become invisible to predatory ants. 'A [coral-eating fish and coral] system is analogous to the chemical system of the caterpillar,' explains Brooker. 'So we thought maybe they were doing a similar sort of thing.'
Brooker and his colleagues looked at the harlequin filefish, a reef-dweller that looks like a coral branch. They wanted to find out if the fish could replicate a reef's smell through its coral-based diet and whether predators could sniff them out.
The team placed a piece of coral and the filefish at opposite ends of a water tank. A coral-dwelling crab was placed in the centre of the tank and 'blind-folded' so it was unable to see which end the coral was at and had to rely on other senses such as smell. The team found that the crab was just as likely to move towards the fish as the coral. '[It] suggests that the smell was a pretty good match,' says Brooker. 'A lot of them did get confused.'
The group carried out a similar test but replaced the crab with cod, a filefish predator, to see if the coral fish could fool the cod's acute sense of smell. They found that the cod were less interested in the filefish if they were close to coral they had fed on. If the filefish was close to a coral that was a different species to the one it had eaten or if there was no coral in the tank, the cod became much more active. The team state this is the first evidence of chemical camouflage in a vertebrate but they do not yet know how it achieves this.
Martin Stevens, an ecologist at the University of Exeter, UK, believes the study could have a wide impact on the wildlife community. 'I think it could be very important in stimulating work looking at chemical camouflage,' he tells Chemistry World. But Stevens adds that more research will need to be carried out on this system before it can be translated to other vertebrates and mammals. 'It's potentially a really exciting and important study,' he says. 'The question, I think next, is how does [this chemical camouflage] work and how widespread is it.'


How to Respond to Tragic Events and CalamitiesQuiz
This quiz is a complementary resource for activity 3 of this lesson: How to Explain Calamities and Tragic Events to Madrassah Children
Through this quiz students are tested on their understanding of how a believer responds to tragic events emotionally, physically and intellectually. Additionally, they are tested on their correct understanding of the concept of Qadar in relation to calamities that no one has control over, ones that are self-caused and ones that are caused by others to us.


text: Tax Credits vs Tax Deductions – What's the Difference? Although these two terms are used interchangeably, when you're discussing tax credits and tax deductions you're not comparing apples to apples. They are very different and knowing the differences is helpful. Tax we owe in any given year is not based solely on our income but is also affected by the various tax dedications and tax credits we are entitled to for that year. Tax Deductions – Reduce Taxable Income Tax deductions reduce taxes differently depending on the marginal tax bracket you're in. For example, if you are in the bottom marginal tax bracket and your marginal tax rate is 15%, then a $100 tax deduction will save you $15. However, let's say you were in a higher marginal tax bracket and your marginal tax rate is 20%, then that same $100 tax deduction will save you $20 instead. Although tax deductions will generally benefit everyone, tax deductions are more effective in saving tax for those that make a higher income and are subject to higher tax rates. Common tax deductions include: RRSP Contributions Childcare Expenses Moving Expenses Tax Credits – Directly Reduce Tax Liability Otherwise Calculated Once your marginal tax rate is applied to your taxable income and the taxes owing is calculated, tax credits are applied in the final stage of this calculation to lower taxes owing even further. Tax credits differ from tax deductions because they reduce taxes independent of the marginal tax bracket you belong in. Tax credits are calculated using the bottom marginal tax rate. In other words, whether you have a taxable income of $30,000 or $200,000, a $100 tax credit will save you the same amount in taxes. Tax credits might bring your final tax owing to $Nil but are generally not going to create a tax refund. Common tax credits include: Medical Expenses Charitable Donations Post-secondary Tuition Bottom line is, tax deductions will save more taxes than tax credits if you are in the higher marginal tax brackets. So remember, you aren't deducting that medical expense, you're claiming a non-refundable tax credit. We hope this brief explanation of the differences between tax deductions and tax credits will help you better understand what's going on inside your tax return. Please call us if you have any other questions or comments.


Remote read replicas - the what, why, and how
PostgreSQL remote read replicas enable users to increase their data availability, as well as read and write performance. Read more to learn how Aiven does it.
03 April 2018
Prem Nallasivampillai
Prem Nallasivampillai RSS Feed
Head of Customer Success at Aiven
Glossary of terms Master: The primary DB instance that is the target of write (and read) operations.
Standby: A DB instance that will be considered for promotion (available for reads).
Read replica: Implies local or remote read-only instance (a.k.a replica).
What is an Aiven for PostgreSQL remote read replica?
When it comes to Aiven for PostgreSQL, until remote replica functionality was released a few weeks ago, there were traditionally two types of DB instances namely, Master, and one or more Standby instances. Each standby instance serves two purposes: the first is to be considered for promotion in the event the master fails, and the other is to serve read-only operations.
Standalone read replica is the newest member to this family. The differences between a standby instance and a remote read replica are that, a remote read replica will never be considered for promotion if the master failed, and a standby is always located in the same region as the master.
As with all flavors of standby and read replica instances (local or remote), the mechanism used to replicate data from the master to the replicas is asynchronous. By not relying on network service quality & bandwidth coupled with the low overhead inherent in PostgreSQL streaming replication, the impact to the write and read performance of the Master DB instance is negligible.
Note: A remote read replica can be set up between homogenous or heterogenous cloud providers. For example, you can have your primary service in Google Cloud (Iowa) and have a read replica in DigitalOcean (New York) or Google Cloud (South Carolina).
Why remote read replicas are a business imperative
At this point, you might be wondering what the big deal is about the new addition. The two most fundamental uses of the remote read replica are to provide greater data availability, and increased performance (throughput and latency) for reads and writes. By offloading reads to the replica, you are essentially doing two things:
1. increase read throughput (fairly obvious), and
2. increase write throughput on the master (not so obvious).
To illustrate, let's say that you have a business-critical application that records online merchandise purchases. In order to record and fulfill those orders you have invested in one of the premium Aiven PostgreSQL plans equipped with a read/write Master and two standby instances, where all the DB instances are located in the same region.
What would happen if the region your Aiven service is running in goes black, as would happen with a natural disaster?. You are then in a situation where you can neither view existing orders, let alone fulfill them. Nor can you record any new orders that your customers want to make from your website. As your sales are impacted, so is your bottom line.
If you were taking advantage of remote read replica functionality, your day would have gone a lot better. Because, the remote read replica will remain fully operational for reads even if the primary region hosting your Master and local replicas becomes inoperable. Therefore, you can continue to fulfill existing orders that were already made.
You can even tweak it so that you can convert the remote read replica to a read/write Master and point your web application to it within a matter of a few minutes, thereby allowing you to continue accepting new orders. In short, a remote read replica provides greater data availability for your business-critical applications.
And availability is just the most obvious benefit of remote read replicas; there are also performance benefits. Especially in the age of globalization, it makes sense to place the data close to consumers. In this case, there may be data that various regional departments share. By allowing for the placement of data close to consumers, a remote read replica makes it more efficient to access.
A similar use case is where massive amounts of data are used in various regions to generate daily performance reports and analytics. Again, replicating and placing this data closest to the regions where the reports and analytics are run for decision makers enables them to make more timely decisions based upon the data. Aiven for PostgreSQL remote read replica feature makes this possible.
How to set up a read replica in 7 steps
Setting up a remote read replica is made convenient through the Aiven Console. Please follow the instructions below to setup a remote read replica for any non-hobbyist Aiven for PostgreSQL plan.
1. Navigate to the Aiven console.
Note: If you don't have a PostgreSQL service running, create a Startup or higher Aiven PostgreSQL service from the Aiven console per Getting started with Aiven PostgreSQL.
existing postgresql service
2. Once your PostgreSQL service up and running, navigate to the service details page by clicking on the service name.
postgreSQL service details]
3. Click on the "Create a read replica" button shown in the bottom-right corner to get to the new remote read replica configuration screen.
postgreSQL service details]
4. Give the remote read replica service a name.
5. Select the Cloud provider who will be hosting the remote read replica service (and the region).
6. Select a plan for the service (default: same plan as the main service).
7. Click "Create" to provision the remote read replica service. Give the service a few minutes to complete startup.
postgreSQL service details
Note: To obtain the credentials to access the remote read replica, simply click on its service name to enter the service details page.
remote-replica service details]
Create your first read replicas today
If you have a business-critical application that requires data (and associated service) to survive complete failure of a cloud provider's region or wish to increase the performance of your existing Aiven PostgreSQL database, take advantage of the Aiven PostgreSQL remote read replica functionality. The cost is will be nominal compared to benefits and peace of mind it will bring.
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text:
Provided by: freewnn-cserver_1.1.1~a021+cvs20130302-4_amd64
catod - To convert the text format of a dictionary to binary format.
catod [-s maxword ] [-R] [-r] [-e] [-S] [-U] [-P dicpasswd ] [-p frepasswd ] [-h cixingfile ] outfilename
This command converts a dictionary from text format into binary format. outfilename is the name of the binary format dictionary. If outfilename is not given, the output will be passed to the standard output device(stdout). The input file may be piped in by using the "<" command. For example, catod basic.dic < basic.u "basic.dic" here is the output binary format dictionary, while the "basic.u" is the input text format dictionary. If the input text dictionary is not given, the input will be taken from the standard input(stdin). To end the input via standard input, press ^D.
-s maxword To specify the maximum number of words. Default is 70000. -R To create a dictionary for both forward and reverse conversion. (Default). -r To create a reverse format dictionary only for reverse conversion. -e If the Hanzi inside the text dictionary contains characters such as space and tab, they will be compacted to special format. (Default). -S To create a static dictionary. -U To create a dynamic dictionary. -P dicpasswd To specify the password for the dictionary. If "-N" is used instead, the password of the dictionary will be set to "*". -p frepasswd To specify the password for the usage frequency file. If "-n" is used instead, the password of the frequency file will be set to "*". -h cixingfile To specify the Cixing definition file.
1. The parts in [ ] are options. They may be omitted. 2. The Pinyin and Zhuyin dictionary has the same format. 3. For details of the dictionary structure, refer to cWnn manual. 13 May 1992 CATOD(1)


Understanding Brake Judder
Brake judder can be felt as a vibration. It is a sensation that can be felt through the steering wheel, your brake pedal and potentially through your seat. Depending on the severity of the judder, you may even feel the car shake. Brake judder can often be an uncomfortable, frustrating and disconcerting experience which may result in the driver reducing their braking pressure to reduce their discomfort, increasing stopping distances as a result.
Drivers and mechanics often jump to one conclusion; that the brake discs are no good and have 'warped'. To fully understand brake judder and diagnose the causes we need to break it down into immediate brake judder or brake judder that has developed over time.
Brake judder symptoms and its causes
If you fit a new set of brake discs to a vehicle and brake judder is immediately felt, the conclusion maybe that discs have been manufactured incorrectly. However, all Apec brake discs are tested before leaving the factory to ensure that this scenario does not occur. Immediate brake judder can only be as a result of a mechanical issue that has not been diagnosed, e.g:
 - A severely worn or damaged hub, hub flange and/or wheel bearing.
 - Severely worn or loose steering and suspension components.
 - Loose wheel bolts.
 - Incorrectly seated wheel/discs.
 - Damaged tyres.
 - Buckled rims.
 - ABS fault.
 - Loose brake components (i.e: carrier).
The list is not exhaustive, however common sense should prevail. If these underlying issues are not resolved, then the issue will remain and potentially lead to catastrophic mechanical failure.
Most frequently, brake judder is not felt immediately and will develop over time. The assumption is that the brake discs are poorly manufactured and are unable to withstand the heat from braking and have warped. However due to modern manufacturing processes and materials used, it is extremely rare for any brake disc to warp. For warping to happen you will need a combination of extreme conditions – eg glowing hot discs and then driving through standing water, or excessive overheating and insufficient cooling.
The true causes of brake judder are far more complicated than the disc warping. The brake disc developing DTV (Disc Thickness Variation) over time, is the most common cause of judder.
DTV – What is it?
Disc Thickness Variation is when the disc has worn unevenly, causing the two friction surfaces of the disc to no longer be parallel with each other (see Figure 1). This is often confused with disc warping. Warping is defined as distortion, where the disc is a uniform thickness in width as shown in Figure 2. There is often little diagnosis that is carried out to solve the issue of brake judder, apart from test driving the vehicle. As soon as judder is experienced, which is blamed on the disc warping, the brake discs are removed and replaced with a new set, curing the issue for the next 2000-5000 miles only for the juddering to return. Disc Thickness Variation is a condition that develops over time, but what causes it?
The primary cause of DTV is uneven material transfer.
What is material transfer?
During the bedding in process, and subsequent braking applications, a microscopic layer of brake pad friction material must transfer evenly from the pad to the surface of the brake disc. This is known as the adherent friction process (please see "material transfer" article). Anything that will affect this process – eg mechanical, or braking style (especially during the initial bedding in period) will result in uneven material transfer, which starts the process of DTV.
Due to uneven friction material transferring across the surface of the disc, this will lead to high-spots. The high spots will heat excessively in comparison to the rest of the disc. If the temperature at these high-spots exceeds 650 deg. C, cast iron changes structurally, transforming into a harder substance called Cementite. As the disc is now composed of varying materials of different hardness, the two materials will wear at a different rate. The important point to note is that this will not immediately induce brake judder but has provided the foundations for a vibration that will eventually lead to irreparable damage to the braking disc, although this may not occur for over 2000-5000 driven miles. This explains why customers often return with their vehicles complaining of brake judder months after the discs were originally installed.
With DTV the disc surface will not have warped, but if measured with a micrometer at (at least) 8 equal points around the brake disc, there will be a variation of thickness. A disc thickness variation greater than the manufacturer's tolerance will result in the symptom of 'brake judder' caused by the brake pads pulsating over the uneven surface. This in turn causes the pistons to kick back over every high spot causing the pedal to pulsate replicating brake judder symptoms. If the manufacturer's data is unavailable, please refer to the below guide.
The precise threshold varies from model to model, dependent upon the general compliance built into the vehicle's braking, suspension and steering systems.
To ensure that the new brake discs that you are fitting do not already have DTV all Apec brake discs are tested before leaving the factory and will have a disc thickness variation of <13µm (<0.013mm).
Skimming the discs will temporarily remove the high spots and judder, however the hard spots of cementite will remain under the surface and the high spots and judder will return after several thousand miles.
As detailed above, a major cause of brake judder is uneven material transfer, leading to Disc Thickness Variation (DTV). The single biggest cause of uneven material transfer is lateral run-out.
Lateral runout
Lateral runout is when the disc is not parallel to the hub surface and therefore deviating from its true axis (see Figure 3).
What causes lateral runout?
 - Not following best practice.
 - Insufficient cleaning of the hub surface (even minuscule particles of rust or debris caught between the disc face and hub can lead to excessive lateral runout).
 - Corrosion build up after the new discs have been fitted. (Using copper grease on the hub surface? not replacing a missing disc location screw).
 - A worn or damaged hub, hub flange and/or wheel bearing.
 - Worn steering and suspension components.
 - Over torqueing of the disc location screw.
 - Over torqueing of the wheel bolt.
 - Low quality refurbished alloy wheels (uneven paint thickness).
 - This list in not exhaustive (further information on lateral runout can be found in our "lateral runout" article).
Other causes of uneven material transfer…
 - Not following best practice
 - The brake pads rubbing on the disc while not braking due to a sticking pad, slider bolt or caliper.
 - The brake pads not contacting the disc evenly when braking due to a sticking pad, slider bolt or caliper.
 - Failure to adhere to the correct bedding in process.
 - Sitting with the brake applied for long periods of time while stationary. (Pad etching).
 - Severe over heating of the discs.
Please see material transfer article for further information.
What else can cause judder?
Static spots
If a vehicle is parked up for an extended period, especially in an area of high humidity and salt content, such as close to the coast, then this can cause corrosion to build up between the disc and pad causing them to adhere to each other. The brakes can be freed off by softly twitching the vehicle by speedily releasing the clutch. The corrosion leads to the formation of static spots which causes severe judder under braking. Should the corrosion be so severe it will also cause damage to the brake pads. Dependent on the level of corrosion on the brake disc there will be judder temporarily while the corrosion is present on the surface of the disc. Should this judder continue, the resolution to cure the judder would be to replace the brake discs.
Brake disc below the minimum thickness
A brake disc is subjected to compressive and centrifugal force, which creates a force of traction. Compressive strength of the disc is the capacity of the disc to withstand clamp load from the brake pads. The compressive strength of a worn disc decreases as it wears. If it exceeds the material's resilient limit, deformation begins as soon as the disc cools down leading to cracks appearing or warping. Therefore it is crucial to replace the brake discs when the braking surface thickness is less than the minimum thickness engraved on the outer disc diameter.
Now that you have a better understanding of the root causes of most cases of brake judder, we can move on and explain the best practices that always need to be adhered to and other preventative steps to eliminate it.
TECHMATE is here to make your life easier
When you need to know more about braking with Apec, ask TECHMATE. Call 01174 288090 or email _EMAIL_


your parts, and then place them into your schematic.
To begin, let's try something easy. Let's search for "op amp" and find the TL071 op amp that we are using in the schematic.
Notice that the part has a drop down arrow. What this means is that the part has multiple packages (surface mount and through-hole) and also has different footprints to choose from. You need to select the footprint for the board you will be using. If you select the surface mount footprint for a through-hole part, you will not be able to assemble your board correctly.
You can tell the difference between a surface mount and through hole part because surface mount will have an abbreviation which starts with "S" and through-hole will have an abbreviation which starts with "D." Aside from the obvious naming conventions, surface mount parts will have pads without holes in the center because the pins are mounted to the surface, and through hole parts have pads with holes in the center because the pins are passed through. It's actually fairly intuitive.
If you look for a resistor, you may be overwhelmed by about a billion different resistor options. Knowing which one to select can be tricky. It's simply a matter of finding the right footprint. Your part supplier should have it's package listed on the product page, which, in turn, should indicate the best footprint to select. Often it is also important to consider the listed measurements (in mm) of the component in relation to the package.
For instance, if we were to look up a 10K resistor we will find that it has an "axial" package. This lets us know it is through-hole, but it still does not tell us the exact footprint we need since axial resistors come in a wide range of sizes. Fortunately, they also let us know the dimensions are 2.3mm x 6mm. From this information we can determine that we need a resistor package with at least 7.5mm spacing between leads (since bending the leads for through-hole mounting requires some additional width). However, to be on the conservative side, I decided go with 10mm spacing between leads.
When the software states "grid 10mm" under the part attributes for this through-hole resistor footprint, it indicates that we have found a resistor package with a 10mm lead spacing and ultimately what we are looking for.
Alternately, this is also where calipers can come in handy. Instead of looking up the lead spacing, we can simply measure the lead spacing and use this measurement to figure out what part footprint to select.
Calipers can also be used to double-check that the measurements given online are correct if something seems fishy.
Sometimes you won't find exactly what you are looking for. In those instances, you can find a similar part with an identical footprint. For instance, I could not find a 1N34A germanium diode, but it has a DO-07 footprint. Instead I am going to use an AA112 germanium diode which also has a DO-07 footprint.
For our purposes, this should be good enough. It will show up on the board as a diode with the correct footprint, and for what we are currently doing, that is all that really matters. If you were going to get deep into Eagle and start running circuit simulations, this might make a difference. However, that is well beyond the scope of this class and our goals.
If you really cannot find anything close to resembling your part, hope is not yet lost. Some manufacturers and part distributors will provide an Eagle parts library for their inventory. A good place to start to look for those is the Element14 Eagle CAD library page. Alternately, you can try googling for a library as well. If that fails, you can always create a new custom part.
To add the library go to (Library > Use...) on the top menu bar. Navigate to and select the library you downloaded and click "open." It will appear nothing happened, but when you now go to add a new part, your new library will be included.
Finally, we need to figure out which components from the schematic don't get mounted directly to the circuit board. In my circuit these parts include the potentiometers, audio jacks, battery snap, and bypass switch. In fact, some of these parts get wired directly and may not have connections to the board at all.
What I need to figure out is precisely what input and output points the board needs. After some thought I concluded I need an audio input and audio output, a connection for the drive potentiometer, and a power connection. To create these terminals, I am going to use the single "pin headers" from the Adafruit library I just downloaded.
Note that there are other "pin headers" I could have used already included with the software, but I just wanted to demonstrate adding a component from the new library.
Step 7: Draw Connections
Once all the symbols are placed, we need to arrange them, name them, and draw the appropriate wire connections.
Select the move tool from the left-hand toolbar (it looks like a compass with four arrows), and click on the symbols to drag them into place. Arrange them on the screen to roughly match the layout of the hand-drawn schematic.
You may notice that sometimes when you click and drag on the symbol it does not go anywhere. This might be frustrating to you, and you might think the software is broken. It isn't that you are doing something wrong. You can only ever select and perform an action upon a symbol when the cross-hair from the tool overlaps the cross-hair on the symbol. Sometimes the cross-hair on the part might be hidden under a symbol or in a corner, making the whole endeavor kind of frustrating.
When appropriate, you can easily rotate the symbols by selecting the rotate tool and then simply clicking on the symbol you want to turn. With each click they will rotate 90 degrees.
The symbols should already have names, but these names may not correlate to the ones already assigned on our paper schematic and B.O.M. Thus, we want to use the Name tool on the left-hand toolbar to reassign the names of the components as appropriate. These names will transfer over to the PCB when we generate it, so it is important that we get them right.
Next we are going to assign values to each symbol using the value tool from the left-hand toolbar. Whereas the symbols have names which specify what sort of part they are, the value designation lets us know what the part actually is. For instance, we can specify whether the resistor R2 is 100 ohm or 10K ohm (as is the case). It should go without saying why assigning values to the symbols is as equally as important as giving them each unique names.
Many of the schematic symbols look the same, even if they have dramatically different footprints. This is particularly true of the capacitors in my schematic. I am going to confirm that each schematic symbol correlates to the proper component by using the info tool from the left-hand toolbar to double check its footprint is correct.
In my case the footprint of the component matches my part perfectly, but if the footprint were not matched to the component, I would then check what other capacitor was incorrect and simply reassign the components that were mislabeled.
Once all of the symbols are arranged and labeled correctly, now it's time to connect them together. To do this we will use the NET tool to create connections between the symbols. All of the connections we make match our hand drawn schematic, with the exception of the components that we have determined do not mount directly to the board. In these cases, we just need to make sure the appropriate pin headers get connected to the appropriate spots.
Often connections will overlap one another without actually connecting. You can tell the difference between a connection and an overlap by the presence of a green dot. For instance, both diodes connect together with the output pin header because all three lines converge at the green dot. However, pins 1 and 2 do not connect together because there is no dot even though they intersect.
Sometimes you might make a connection which looks okay on first glance, but is not a connection at all. You can see an example of a bad connection here on pin 3. The long darker green overlapped section indicated that there isn't actually a connection there. An actual connection should look like the small green dot on pin 2.
To fix this, you need to delete the green line by selecting the Delete tool from the left-hand toolbar. This is easy to find because it looks like a little garbage can. Once the tool is selected, click on the line to delete it, and then you can go back and redraw the line with the NET tool.
When you have a lot of symbols connecting with one another, your circuit can get confusing very quickly. An easy way to tell if a connection is good is by moving the symbol you are unsure about and observing to see if the connections get dragged along with it. If they all appear to move around with the symbol, the connections are reliable.
Finally, once all of the connections are made and you have meticulously double-checked your work to make sure that it matches your hand drawn schematic, you are finally ready to make a circuit board.
Now would be a good time to get up, stretch your legs, eat a sandwich, or — if you are gluten free — have some rice pasta. If you are feeling particularly inspired, maybe even go for a walk. You need to reset your brain for the next lesson, and some exercise wouldn't kill you.
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Frequently Asked Questions
Do savings such as stocks, trusts, and other investments students may have count as part of their student contribution?
Yes, students' savings are considered just like parents'. The calculation on the student side considers a percentage of the value of their savings without any of the asset protection parents have in their calculation.


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Whatever Happened to the Affluent Society?
Whatever ever happened to the 'Affluent Society'?
With economic markets in turmoil the world over, do we need a fresh rethink on the economy of the 'West'? Martin Hickes reports.
Just over 50 years ago, the renowned American economist and liberalist J K Galbraith published his seminal work 'The Affluent Society'.
Canadian-born Galbraith, lionised in some quarters as the 'Einstein' of the sometimes arcane world of economics, envisioned a new post-war liberalism, calling for a 'new economics' to reflect the rise of a war-torn world out of austerity and poverty.
With the direction of the US and the world economies at perhaps their biggest post-war crossroads ever, and at a time when the very nature of capitalism is being questioned, it is time for an economic re-think?
With many struggling to repay mortgages, and the global credit crunch biting hard, have we finally come to the end of the 50-year bubble of the US-led economy and Galbraith's socio-economic utopia?
With the collapse of major banks only just avoided recently, some dyed-in-the-wool stock market traders are considering the efficacy of the'system'.
Economists at home and abroad are beginning to consider whether a new 'Galbraithian' 're-boot' is needed.
Dr Stephen Dunn, author of the forthcoming book 'The Economics of John Kenneth Galbraith' (Cambridge University Press, pub. 2009), formerly at Leeds University, and an influential strategy director for the NHS, says it would do no harm to revisit Galbraith's philosophies.
He says: "Galbraith was considered an iconoclast by many economists and a hugely successful bestseller both in the US and Britain, reaching into the homes of the discerning reader on both sides of the Atlantic.
"He rejected the technical complex models of classical economics as being too remote from an economic reality and believed national and global economies could not be dictated by 'written in stone' laws.
"Rather he thought the big picture of world economics was a complex product of the cultural and political mix in which it existed, which defied 'conventional wisdom' - the phrase he coined - or typical economic models.
"In 'The Affluent Society (1958)', and also The Great Crash (1954) he opined, to become successful, post-World War II America should make large investments in items such as highways and education using funds from general taxation among other theories.
"But first and foremost he said economics must have a social relevance to the man on the street.
"Given he had the ear of more than one US president, the book became a best-seller and contributed to Kennedy and Johnson's 'war on poverty' and subsequent government-led public spending programme."
Harvard-educated Galbraith worked on the book while in Switzerland, and had originally titled it The Opulent Society but changed it to The Affluent Society at his wife's suggestion.
In such he wrote: 'The world is a newly affluent place. Economic growth has brought enormous changes to the ways in which the populations of the Western world live.
 'Society's perceptions are highly conservative. People invest heavily in these ideas, and so are heavily resistant to changing them.
 'Then the conventional wisdom quietly dies with its most staunch proponents, to be replaced with a new conventional wisdom.... it is armed with the evidence of recent events which make the current conventional wisdom increasingly untenable.'
 Dr Dunn adds: "Galbraith was a hugely influential figure on shaping and influencing the course of events and intellectual debate over the long twentieth century.
"Those seeking to develop a realist vision of the economy would be wise to further consider his economic and social theory.
"At 6' 8", both in style and physical appearance, he did not conform to the caricature of an ivory tower academic.
"He is principally associated with writing a series of intellectually demanding yet rewarding books aimed at a general readership in order to alert the public to the social consequences of the major transformations in economic structure that were occurring.
"His disdain and sarcastic wit targeted abuses of business power and the sometimes unjust accumulation of private wealth, in the context of poor and underfunded public services.
"Nevertheless many of the tributes and obituaries that followed his death in 2006 identified him principally with a vision of the Post War economy dominated by large bureaucratic corporations, unfettered by the demands of consumers and financiers alike – something unthinkable today.
"In the days that followed his death little serious reflection was given to Galbraith's enduring contributions to economic theorizing and many continue to write him off as a product of his age.
"The conventional reflection noted his colourful life, celebrated his mordant wit and prose, yet generally castigated his obsolete theorizing as without lasting merit.
"But for Galbraith the aim of a socially relevant economics was to be in touch with the great problems of our time. And as times change and history moves on, so must our analysis."
"Galbraith's monetary and financial analysis recognises the 'dark forces of time and uncertainty' and the euphoria and speculation that accompanies institutional evolution.
 "Easier credit checks, lower down payments, longer repayment terms, and other inducements for people to go further and further into debt are permanent are necessary fixtures of the consumer society described in The Affluent Society."
"He recognized the significant economic power held by large firms, and that such power was one of the main reasons for the success of the US economy in the post World War II era.
"But he also saw that this concentration of power also created a range of unintended problems – social and environmental.
"For these reasons he suggested society must counter the power of the large firm and the wealthy, and ensure the provision of those essential goods and services that are underprovided. The state must also use its power to mitigate macroeconomic problems such as financial instability, unemployment, inflation and poverty.
"Especially today, Galbraith's philosophies remain relevant. Individuals do not always act in ways that fulfil their happiness, challenging one of the basic building blocks in conventional economics.
"The recent Nobel Prize winner in economics Daniel Kahneman has shown that individuals do not conform to the rules of economic rationality and make systematic mistakes.
"Likewise, it has become more widely remarked that financial markets are driven by "irrational exuberance" and are not as efficient or rational as the conventional wisdom would have us believe.
"Many are concerned that large firms dominate the setting of prices and wages and shape consumer desires through advertising and marketing and that public goods such as transportation and universal access to health care are essential to social welfare and to economic growth.
"Increasingly in the popular press it is argued that fiscal policy – using government spending and changes in tax rates to stimulate growth – can be effective, but must be channelled to those that need it.
"For all these reasons, the economic contributions of J.K. Galbraith deserve lasting attention."


text:
1 August 2002
Test your knowledge with CCST...
The following sample questions (not actual exam questions) appear in the Certified Control System Technician (CCST) study guide published by ISA.
The content area for these questions is Domain 1—calibration.
1) If a cubic foot of water weighs 62.4 pounds, it exerts a pressure of how many pounds per square inch (psi)?
2) Head is another way of expressing:
3) Approximately what is the pressure, in psi, at the bottom of a 20-foot tank filled with a fluid that has a specific gravity of 1.5?
1) Imagine a cubic foot of water. It's 12 inches wide, 12 inches back, and 12 inches high. Because the base of this cube of water is 12 by 12, we know that the base is 144 square inches. The question asks how many pounds per square inch does the box exert. Put 62.4 pounds in the numerator and 144 square inches in the denominator, divide, and you get 0.433 psi—answer C.
2) The correct answer is B.
3) Specific gravity (SG) is the density (mass/volume) of a substance with reference to the density of water. Thus, the SG of water is 1.0. A substance, which has an SG of 1.5, as in this problem, has 1.5 times the mass of water. So if we take the calcula tion from question No. 1 above, which asked for the psi of a 1-foot-high column of water, and multiply it by 20, we get the psi of the 20-foot-high column for this problem. Now we multiply that by 1.5 because the substance in this problem has 1.5 times the mass of water (0.433 x 20 x 1.5 = 12.99), and we get the answer, B.
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text: The aim of this research was to explore why workers in health and social services embarked on a Certificate in Community Care Practice and the extent to which they felt knowledge learnt related to their every‐day work practice. The objective was to indicate how useful more academic courses are for health and social care staff, and to find out the kinds of barriers to practicing theory learnt in the classroom students face in their 'real world' of work. Data was collected from 25 mature students (over half were between the ages of 41–50 years), 3 of whom were men from a range of professional backgrounds including; support staff working in residential and domiciliary services and informal (unpaid) carers for people with learning disabilities, mental health difficulties as well as older people. Quantitative (an adapted questionnaire) and qualitative (focus group session which was an integral part of classroom learning about research methodology) methods were employed. Data was analysed using SPSS and thematic analysis. Findings indicated that the main motivators for study was to gain a qualification and for personal development. Students reported their increased desire to link theory learnt which they found highly relevant to their everyday practice, but organisational barriers sometimes precluded them from doing so. The paper ends with policy and practice recommendations.


text:
technical article from Blue Sea Systems
September 17, 2007
Standard circuit protection may not guard against two ground fault hazards in marine AC circuits:
- AC electric power leakage from boats into the surrounding waters that may cause electrically induced drownings
- Low level ground faults that do not trip ordinary circuit breakers but can lead to fires and shocks to people on board
A ground fault occurs when current leaks from the AC hot wire to ground through faulty insulation, improper wiring, or failing appliances and devices. Ground Fault Circuit Interrupters (GFCI) found on most boats provide leakage current protection for equipment connected through a plug and receptacle. ABYC guidelines recommend 5mA GFCIs for receptacles in heads, galleys, machinery spaces, and weather decks.
However, wiring faults and shock exposure also can occur in permanent wiring and permanently connected appliances. Providing protection for these conditions requires additional ground fault protection.
Boat systems pose high risk. There is greater potential risk in electrical systems on boats compared to typical home or commercial wiring. The marine AC electrical system is supplied from shore by a power cord through plug and socket connections. The atmosphere is corrosive and the cord is subject to motion, chafing, and stress. Even though a safety ground conductor is supplied in the cord, it may not be completely reliable. A good electrical connection to the shore grounding system can fail in the marina wiring, the cord connections, or at connections inside the boat.
RCDs. GFCIs are Residual Current Devices (RCD). RCDs measure current flow in the hot and neutral wires. Current in these wires should be balanced-when 10 Amperes is flowing in the hot wire, 10 Amperes also should be flowing in the neutral wire (see diagram below). A current imbalance may be an indication of a ground fault-stray current leaking from the hot wire through defective insulation and possibly through a potential victim to ground. RCDs immediately switch electricity off when a ground fault is detected. GFCIs are RCDs with a trip level and timing that conform to a specific UL Standard.
RCBOs. Residual Current Breaker, Overload (RCBO) devices combine the ground fault protection of an RCD with the familiar overcurrent tripping characteristic of a normal circuit breaker. RCBOs can be installed as Branch circuit breakers providing 5mA ground fault protection, or as Main circuit breakers providing 30mA ground fault protection.
5mA vs. 30mA stray current protection. The sensitivity of GFCIs in the U.S. is 5mA to protect against shocks that might cause loss of muscle control for the most sensitive members of the population. 5mA sensitivity is ideal for single circuit protection; however, it is not suitable for whole system protection. The problem with 5mA sensitivity as a whole system solution is that typically there is cumulative leakage in excess of 5mA throughout a whole AC electrical system. Installing an RCBO with 5mA leakage trip sensitivity to protect an entire AC wiring network will result in nuisance tripping. Therefore, 5mA devices are restricted to use in single branch circuits.
In Europe, normal practice is to install a 30mA RCBO in the Main AC circuit as close to the power inlet as possible. This provides whole system protection. If a victim completes the circuit by touching a live conductive surface, normal AC line voltages will produce current in excess of 30mA through the typical human body. Therefore, 30mA protection can immediately switch the electricity off as quickly as a 5mA device in the event of direct human contact.
Protection from electrically-induced drowning. Increased interest in achieving a higher level of ground fault protection in the U.S. is generated by investigations into electrically induced drowning accidents in marinas. These investigations indicate that numerous drowning accidents in marinas have been caused by ground faults resulting in current leakage from boats into the surrounding water. An electrically induced drowning results from loss of muscle control caused by electrical current leaking into the water from boat fittings.
Electrical leakage into the water and the hazard it causes to swimmers is substantially different than touching a live wire on shore. Loss of muscle control can occur at 5mA. This might lead to the conclusion that for current leakage protection to be useful, it must be 5mA or lower. However, unlike a person on land touching a live wire and completing a fault circuit, water is conductive and will complete the fault circuit even if a swimmer is not present. In fact, when a fault develops, an RCBO that provides leakage protection of 30mA may break the circuit before a swimmer is in the area. Furthermore, when a swimmer is in the water, the swimmer shares leakage current with the surrounding water, so the swimmer's share of the leaking current will be less than the total current.
Individual circuit protection and whole boat protection. There is value in having both 30mA whole system protection and 5mA individual circuit protection. A 30mA Main circuit RCBO reduces fire and shock hazards from defects in permanently installed appliances such as water heaters, battery chargers, lighting fixtures, etc., and against defects in the wiring distribution system itself. A 5mA Branch circuit RCBO or GFCI provides a greater level of protection in specific areas such as heads, galleys, engine rooms, and weather decks where there is increased risk of shock. In boats with installed GFCIs, additional protection can be obtained by installing a Main circuit RCBO.
Additional information about RCBOs is available in the 2008 Blue Sea Systems catalog on pages 21.