text:
The genus Monstera is represented in Mexico by nine species, of which five are reported for the region of Los Tuxtlas, Veracruz. During fieldwork between 2014 and 2019 in Los Tuxtlas, we discovered a previously undescribed species belonging to Sect. Marcgraviopsis and consisting of a third species from Mexico with a pendent habit. The new species Monstera guzmanjacobiae, is described taxonomically and illustrated, using color photographs of vegetative and reproductive features in living material. The behavior of flowering coincides with that observed in other species of Monstera. Both nitidulid beetles and drosophilid flies found inside the chamber may be the pollinators of M. guzmanjacobiae.
- Los Tuxtlas


American Chemical Society
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se0c00267_si_001.pdf (526.75 kB)
Determination of Serotonin Concentration in Single Human Platelets through Single-Entity Electrochemistry
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journal contribution
posted on 2020-06-19, 14:33 authored by Jungeun Lee, Yeji Kang, Jinho Chang, Jaewoo Song, Byung-Kwon Kim
This research introduces a method to directly detect serotonin in a single platelet through single-entity electrochemistry. Platelets isolated from human blood were analyzed by cyclic voltammetry and current–time measurements. When a single platelet collides with an ultramicroelectrode, serotonin inside the platelet is oxidized at the electrode surface, and an anodic current peak is consequently observed during measurement. The concentration of serotonin can be determined by integrating this peak current. In addition, this method can be used to determine the platelet concentration. Analysis of the collision frequency of platelets can provide information about the platelet concentration in the blood. As a result, platelet levels and serotonin concentrations in single platelets can be measured quickly and easily.
History


text:
Inquisit Language Reference
The number of times the specified element has been run withing the current block.

If the element is a block, this property always returns 1 because a block can only be run once within a single block. If the element is a trial, this property returns the number of times the given trial has been run within the block.
The following displays the value of count in a text stimulus:
/ items= ("count = <% trial.sometrial.count %>")
The following displays the value of count in an instruction page:
count = <% trial.sometrial.count %>

source: openbmb/Ultra-FineWeb


text:
WITH 30 years passing since the night Mount Macedon was ravaged by fire, the region is bracing to remember those who died and the emergency crews who helped prevent further tragedy.
The Ash Wednesday fires of February 16, 1983, claimed 75 lives and destroyed more than 3000 homes.
Locally, the fire spread from East Trentham to Mount Macedon, killing seven people, destroying more than 600 homes and buildings, and devastating wildlife and bushland.
Until the Black Saturday bushfires in 2009, they were the deadliest in Australia's history.
Macedon Ranges Shire mayor Roger Jukes said the 30-year anniversary was a time for remembering the people who lost their lives, as well as acknowledging the enormous effort of emergency services personnel and community members who fought hard to restrict the fires spreading further.
"For our community, the legacy that Ash Wednesday and other major bushfires has left is an increased knowledge of what fire can do and acceptance of fire as a natural occurrence," he said.
"We wish to acknowledge those who were affected by these devastating fires and celebrate the community's efforts to work together to recover from this disaster."

source: HuggingFaceFW/fineweb-edu


Scientists explain squirrel promiscuity
QMI Agency
First posted: | Updated:
It's not in the genes, but in the number of knocks at the door.
Researchers at the University of Guelph have found that something a lot more circumstantial than genetics is behind female squirrels' promiscuity.
"Their behaviour is overwhelmingly influenced by opportunity," said Erin McFarlane, a graduate student and member of the team that looked into this issue that has long baffled biologists.
The findings are published in the Royal Society journal Biology Letters.
Female squirrels are known to sometimes have as many mates as possible, behaviour that doesn't always make sense for females, McFarlane said.
The researchers found that the more males there were in the area interested in mating, the more squirrels a female would mate with, McFarlane said.
"A female squirrel that only chose to mate with one male could have a daughter that mates with many males," integrative biology professor Andrew McAdam said in a release. "It seems the tendency to mate with fewer males isn't something that is being passed down from generation to generation."
The discovery that the mating patterns of female squirrels aren't genetic means mating habits in the species are unlikely to evolve, the researchers found.
The researchers analyzed data from 108 mate chases involving 85 female squirrels. The female squirrels mated with anywhere from one to 14 partners.
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text:
Press Release - Peoples Liberation Front Enters The Hackers Space Race
Sunday - February 19, 2012 11:30 PM CT
Today the PLF announces the launch of "Operation Freedom Star". The mission of this Op is simple. The Peoples Liberation Front is entering the Hacker Space Race that was initiated with the announcement by the Chaos Computer Club that they intended to launch three communications satellites of their own to help circumvent internet censorship. The PLF states that we are in this race to win, and that WE firmly intend to be the first hackers in space.
Our plan for this involves the purchase of one of the many used communications satellites that are in orbit already, and are beyond their commercial usefulness. Many of these birds are low on fuel and have other issues related to their age, but are otherwise serviceable and useful for the purpose we intend - which is to provide broadband satellite communications to areas of the world that are in great need. We are currently looking at several possibilities, and whichever bird we chose - it will be called the "Freedom Star". The purpose of the Freedom Star Satellite will be to provide broadband internet connections using commercially available downlink hardware.
Once we have our first bird working, we will shift our focus to building our first custom bird from scratch. We will use the Amsat program to design and launch our own bird, and also study the open source communications satellites already launched as part of this incredible program for possible uses in circumventing censorship, internet shutdowns - and providing other services to freedom movements around the world.
To coordinate this massive effort, we hereby create the PLF Space Command - which will be staffed for the purpose of managing all the space related efforts of the Peoples Liberation Front. The attached Op Poster for Operation Freedom Star contains the new logo for the PLF Space Command. And finally, if you support this effort, we have set up a sand-boxed WePay fund to collect online donations of much needed cash which will be used specifically for this project. The budget just for the first year of this effort is in excess of 1 million USD, so please give generously if you support the idea.
SIGNED -- PLF Central Command
Operation Freedom Star Poster - _URL_

source: m-a-p/FineFineWeb


text:
For the first time in its more-than-100-year history, Campbell Soup is making available to the American public specially cultivated seeds used to grow tomatoes for its iconic Campbell's® Tomato soup.
The effort is part of Campbell's goal to grow more than one billion tomatoes across the country and to support American agriculture.
Campbell also is teaming up with the National FFA Organization and Urban Farming Inc., each of which will use the special seeds to help create five community gardens in urban communities.
Through June 21 (or while supplies last), each household that purchases any variety Campbell's condensed soup and enters the code on the can at HelpGrowYourSoup.com can request a free packet of Campbell's tomato seeds to plant in their own backyards and windowsills. With each request, Campbell will donate the seeds being used to plant community gardens and achieve the one-billion-tomato goal.
The project is tied to a current trend of people seeking to grow their own food in their own gardens.
Introduced in 1897, Campbell's Tomato soup was the first condensed soup in the company's history and to this day remains an American favorite. It is one of the company's top-selling soups and is eaten by more than 25 million people at least once a week. In fact, pop culture artist Andy Warhol ate tomato soup for lunch for more than 20 years, inspiring him to create his famous Campbell's Tomato soup painting.
The tomato seeds themselves also have a rich heritage. Campbell began growing tomatoes from its own seeds on New Jersey farms during in the 1930s. Those "Jersey" tomatoes were renowned for their rich taste and texture, so much so, that when truckloads were delivered to the Campbell facility in Camden, city residents followed and picked up fallen tomatoes from the streets.


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To be certified and maintain certification every year as a Virginia Master Naturalist, volunteers are required to complete 8 hours of continuing education. To assist volunteers needing to meet this requirement, the state program offers continuing education through the annual statewide conference and an online webinar series. Online resources of the Virginia State Master Naturalist web site can be accessed through this link: _URL_
Other education opportunities are announced through our Chapter newsletter, e-mail broadcasts and at our general membership meetings. Also attending speaking events (e.g. at colleges and civic organizations) and and conservation related public agency meetings (local, state, federal) can also count toward continuing education hours, with the approval of the Chapter Advanced Training Committee Chairperson.
Many online resources from our State Agency Sponsors also offer education opportunities (peruse links below).
- Virginia Cooperative Extension
- Virginia Tech College of Natural Resources and Environment
- Virginia Tech Department of Forest Resources and Environmental Conservation
- Virginia Department of Conservation and Recreation
- Virginia Department of Environmental Quality
- Virginia Department of Forestry
- Virginia Department of Game and Inland Fisheries
- Virginia Museum of Natural History
Continuing education is a great way to keep abreast of the latest goings-on and to brush up on knowledge in your areas of special interest.


text:
Want to beat your Scrabble friends no matter where you are?WordSolver Android App!
10 Definitions of Scenes
The definition of scenes, the meaning of the word Scenes:
Is scenes a scrabble word? Yes!
- n. - The place where some action occurs
- n. - An incident (real or imaginary)
- n. - The visual percept of a region
- n. - A consecutive series of pictures that constitutes a unit of action in a film
- n. - A situation treated as an observable object
- n. - A subdivision of an act of a play
- n. - A display of bad temper
- n. - Graphic art consisting of the graphic or photographic representation of a visual percept
- n. - The context and environment in which something is set
- n. - The painted structures of a stage set that are intended to suggest a particular locale
Scenes is worth 8 points in Scrabble, and 10 points in Words with Friends
There are 6 letters in scenes: C E E N S S
1 Anagram of Scenes
Words that can be created with an extra letter added to scenes:
24 words found using the letters in "Scenes"
6 Letter Words
5 Letter Words
4 Letter Words
3 Letter Words
2 Letter Words


text:
Porter explored the natural world around him and became known for
making pleasing photographs of nature. To accomplish his goals,
he became expert at finding interesting details, such as these luna
moths that blend in with their surroundings (look closely and you
will see two moths in this image). He loved the outdoors and would
spend hours exploring.
- Where would you go to find nature in your community?
- How would you describe nature in your community through close-up photographs?
- Look at the range of greens Porter captures in this photograph. What other colors do you see?
Porter's attention to details of nature, as seen in this image,
helped raise awareness and build support for saving natural places.


text:
2. Place the bit in the ding and line up the drill so it is exactly perpendicular to the pot.
3. Press the drill firmly into the container and then drill through the container in a single motion. To prevent your drill bit from slipping around when working with metal containers, first make a shallow hole with a very small drill bit and then drill completely through the pot with the larger bit.


text:
How To Remove Hair Dye From Bathtub. Sometimes when you dye your hair and it is not quite at its best, some of that dye may end up on your bathtub.
This can potentially be a devastating problem. But have no fear. There are many different methods that you can use to ensure that your bathtub will be as clean as ever.
One way may work better than another depending on the situation of what might have been used or how badly affected the tub is, but that doesn't mean you should discount trying other suggestions when the need for them arises.
How To Remove Hair Dye From Bathtub
The stain can be removed with bleach and water. Wait 5-10 minutes before cleaning. If you wipe away the fluid, the sweater will look years younger. By spreading it on a clean rag, acetone can be used to clean fabric surfaces. Cleaning up soapy tub water is quick and easy with baking soda and water paste.
In this article, we will show you how to remove hair dye from a bathtub.
Using Rubbing Alcohol
Rubbing alcohol is a great way to kill germs. However, it can easily take out the stain caused by a recent bathtub hair dye session, unless of course, you used a black hair dye because rubbing alcohol will only lighten the stubborn stain.
The first step is to wipe the sink clean with your cleaning cloth and then apply rubbing alcohol to the stained area to remove any excess water from earlier.
Then use your damp cleaning cloth or sponge to rub over the faded part of the stained area and let it dry before wiping again.
Using Nail Polish Remover
Nail polish remover is likely already in your possession. If you have dye stains in your bathtub, use a nail polish remover that contains acetone to remove them.
The stained area can be treated with nail polish remover with acetone using a cotton ball. If the stain is on a painted surface or a finished surface, it will remove the color completely.
Bleach is not only great for removing hair dye from surfaces around the bathroom but it can also be used to remove mildew that dirties your counters and tub.
Two cups of bleach are mixed with two cups of hot water and poured over the stain. The solution should sit for ten minutes before being thoroughly rinsed.
It's important to always open a window or use an exhaust fan while using bleach because it can become quite pungent, especially if you have sensitive skin.
Using Baking Soda
In addition to being an effective remedy for removing stubborn stains, this mixture is also a highly recommended bathtub cleaner and hair dye remover treatment.
To make a paste, it's best to start by mixing baking soda with a bit of water until it becomes thick not too runny as it will be difficult to remove later.
Use the brownish mixture to scrub away hard-to-remove stains from bathtubs and other stained surfaces like hair dye.
Mixing borax with water and scrubbing it on the dye stains inside the bathtub is one of the most convenient ways to remove them.
Take a handful of borax and mix it with about 1/4 cup of water and stir it together until smooth, rub the mixture into the stained area with a clean scrubber, apply some pressure as you scrub, and then wipe it clean with clean water.
Is it possible to permanently stain a bathtub with hair dye?
Almost anything it comes in contact with can be stained by semi-permanent hair colors. Skin, bathtubs, sinks, and clothes can all be stained.
To remove excess dye and petroleum jelly from your bathtub, wash and scrub it after rinsing your hair of color. When you increase your activity levels later on in the day, you may slip on the tub if you haven't done this.
Is it possible to wash hair dye out of the bath?
You can easily remove dye from your face, neck, ears, arms, and other areas. Take a cotton ball and wipe any remaining dye from the skin.
You can directly pour some rubbing alcohol onto a cotton ball and dab it away from your face while avoiding contact with your eyes. Avoid contact with your eyes or mouth after thoroughly rinsing with warm water.
How to Remove Semi Permanent Hair Dye from Bathroom


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MarkLogic Server 11.0 Product Documentation
GET /v1/alert/rules
Summary
Retrieve the definition of all alert rules previously installed in this REST API instance using the /v1/alert/{name} service.
URL Parameters
database? Perform this operation on the named content database instead of the default content database associated with the REST API instance. Using an alternative database requires the "eval-in" privilege; for details, see Security Requirements in the REST Application Developer's Guide.
format? The expected content type of the results. This is equivalent to specifying the format in the Accept header. The format parameter overrides the Accept header if both are present. Accepted values: xml and json. Default: xml.
Request Headers
Accept* The expected MIME type of the information in the response. Accepted types: application/json or application/xml. Ignored if the request includes a format parameter value.
Response Headers
Content-type The MIME type of the data in the response, either application/json or application/xml, depending upon the MIME type requested through the format parameter or Accept header on the request.
Response
On success, MarkLogic Server responds with a 200 status. The data in the response body is definitions of all installed rules. Results can be returned as either XML or JSON, depending up on the format request parameter or the Accept header setting. For details on the format of rule definitions, see Defining an Alerting Rule in the REST Application Developer's Guide.
If the Alerting API is not enabled, MarkLogic Server returns status 403.
Required Privileges
This operation requires the rest-reader role, or the following privilege:
_URL_
Usage Notes
The expected response type can be specified using either the format parameter or Accept header. One or the other must be supplied. If both are supplied and are different, the format parameter takes precedence.
Example
$ curl --anyauth --user user:password -X GET -i -H "Accept: application/xml" \
 'http://localhost:8000/v1/alert/rules'
==> The definitions of all installed rules, as XML. MarkLogic Server
 responds with output similar to the following:
HTTP/1.1 200 OK
Content-type: application/xml; charset=utf-8
Server: MarkLogic
Content-Length: 542
Connection: Keep-Alive
Keep-Alive: timeout=5
<rapi:rules xmlns:rapi="_URL_
 <rapi:rule>
 <rapi:name>example</rapi:name>
 <rapi:description>An example rule.</rapi:description>
 <search:search xmlns:search="_URL_
 <search:qtext>xdmp</search:qtext>
 <search:options>
 <search:term>
 <search:term-option>case-sensitive</search:term-option>
 </search:term>
 </search:options>
 </search:search>
 <rapi:rule-metadata>
 <author>me</author>
 </rapi:rule-metadata>
 </rapi:rule>
</rapi:rules>

Example
$ curl --anyauth --user user:password -X GET -i -H "Accept: application/json" \
 'http://localhost:8000/v1/alert/rules'
==> The definitions of all installed rules, as JSON. MarkLogic Server
 responds with output similar to the following:
HTTP/1.1 200 OK
Content-type: application/json; charset=utf-8
Server: MarkLogic
Content-Length: 190
Connection: Keep-Alive
Keep-Alive: timeout=5
{ "rules": [
 { "rule": {
 "name": "example",
 "description": "An example rule.",
 "search": {
 "qtext": [ "xdmp" ],
 "options": {
 "term": { "term-option": [ "case-sensitive" ] }
 }
 },
 "rule-metadata": { "author": "me" }
 } }
] }

Stack Overflow iconStack Overflow: Get the most useful answers to questions from the MarkLogic community, or ask your own question.


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RATIONALE: Perceptual learning operates on distinct timescales. How different neuromodulatory systems impact on learning across these different timescales is poorly understood. OBJECTIVES: Here, we test the causal impact of a novel influence on perceptual learning, the androgen hormone testosterone, across distinct timescales. METHODS: In a double-blind, placebocontrolled, cross-over study with testosterone, subjects undertook a simple contrast detection task during training sessions on two separate days. RESULTS: On placebo, there was no learning either within training sessions or between days, except for a fast, rapidly saturating, improvement early on each testing day. However, testosterone caused "off-line" learning, with no learning seen within training sessions, but a marked performance improvement over the days between sessions. This testosterone-induced learning occurred in the absence of changes in subjective confidence or introspective accuracy. CONCLUSIONS: Our findings show that testosterone influences perceptual learning on a timescale consistent with an influence on "off-line" consolidation processes.
Original publication
Journal article
Psychopharmacology (Berl)
Publication Date
451 - 457
Adult, Analysis of Variance, Contrast Sensitivity, Cross-Over Studies, Double-Blind Method, Female, Humans, Learning, Neuropsychological Tests, Photic Stimulation, Testosterone, Time Factors, Young Adult


In the US, Hibistat (chlorhexidine topical) is a member of the following drug classes: antiseptic and germicides, mouth and throat products and is used to treat Skin Disinfection, Preoperative.
US matches:
Ingredient matches for Hibistat
Chlorhexidine digluconate (a derivative of Chlorhexidine) is reported as an ingredient of Hibistat in the following countries:
 - United States
International Drug Name Search


Take the 2-minute tour ×
OpenCV SURF implementation returns a sequence of 64/128 32 bit float values (descriptor) for each feature point found in the image. Is there a way to normalize this float values and take them to an integer scale (for example, [0, 255])?. That would save important space (1 or 2 bytes per value, instead of 4). Besides, the conversion should ensure that the descriptors remain meaningful for other uses, such as clustering.
share|improve this question
2 Answers 2
There are other feature extractors than SURF. The BRIEF extractor uses only 32 bytes per descriptor. It uses 32 unsigned bytes [0-255] as its elements. You can create one like this:
Ptr ptrExtractor = DescriptorExtractor::create("BRIEF");
Be aware that a lot of image processing routines in OpenCV need or assume that the data is stored as floating-point numbers.
share|improve this answer
You can treat the float features as an ordinary image (Mat or cvmat) and then use cv::normalize(). Another option is using cv::norm() to find the range of descriptor values and then cv::convertTo() to convert to CV_8U. Look up the OpenCV documentation for these functions.
share|improve this answer
Your Answer


text:
UWinnipeg's Newest Canada Research Chair:
Focus on Indigenous Science Education
The University of Winnipeg's Dr. Dawn Sutherland was named Canada Research Chair in Indigenous Science Education Wednesday as part of a $66.9 million announcement in Ottawa of 90 Canada Research Chairs by the Honourable Maxime Bernier, federal Minister of Industry and minister responsible for the Canada Research Chairs program.
In her research, Dr. Sutherland, Associate Professor in Education, plans to explore the relationship between culture and science education in indigenous communities, in particular in Manitoba. One of her goals is to see the teachings of Aboriginal culture incorporated into school curricula so that science education is more meaningful, interesting, and relevant for Aboriginal students.
Dr. Lloyd Axworthy, University of Winnipeg President and Vice-Chancellor stated that this initiative is part of a broader strategy underway at UWinnipeg to make education more accessible to and inclusive of Aboriginal peoples and culture.
"This project complements our holistic approach to Aboriginal education," said Dr. Axworthy. "The Canada Research Chair in Indigenous Science Education builds on our University's growing expertise and resources in this area such as our new Aboriginal Student Services Centre and the innovative Wii Chiiwaakanak Learning Centre. This combined with the generous support of our partners in both the inner city of Winnipeg and the Aboriginal community as a whole are benefiting not only our students and researchers, but future generations of Aboriginal students."
A five-year, $500,000 appointment, this Canada Research Chair builds on Dr. Sutherland's expertise teaching education students in the field of science. Sutherland incorporates traditional Aboriginal knowledge into her science lessons, and participates in an international committee dedicated to exploring how culture, language, and gender influence learning. She is collaborating with colleagues from around the world to develop an academic framework for teaching science to Aboriginal students that teachers can follow in their classrooms. In addition, she is in the process of establishing a centre where research in this area can be carried out.
"The idea is to make science learning relevant and interesting—to put it into a context that students are exposed to day to day," said Dr. Sutherland. "For some students, this means developing creative techniques, such as incorporating the indigenous knowledge of trappers, Elders, Aboriginal community members who live off the land, to help students engage with the science curriculum."
Dr. Sutherland is the fifth University of Winnipeg professor named as a Canada Research Chair. Dr. Mavis Reimer is Canada Research Chair in the Culture of Childhood, Dr. Jennifer Brown is Canada Research Chair in Aboriginal Peoples in an Urban and Regional Context, Dr. Tom Carter is Canada Research Chair in Urban Change and Adaptation, and Dr. Jacques Tardif is Canada Research Chair in Tree Ring Research.
The Canada Research Chairs program, part of an overall Government of Canada plan to encourage Canada's innovation, promotes leading-edge research and innovation in universities; provides exciting opportunities for Canadian researchers; and, attracts the best research minds in the world to Canadian universities.


text:
Definition from Wiktionary, the free dictionary
Alternative forms
- The conversion of something in order to make it international
- (software engineering) The act or process of making a product suitable for international markets, typically by making text messages easily translatable and ensuring support of non-Latin character sets.
conversion of something to make it international
act of making something suitable for international markets


text:
Lasers to replace quartz technology
In a new discovery, researchers have found that lasers can safely replace years old quartz technology used in wristwatches or to transmit reliable signals to radios.tech reviews Updated: Jul 18, 2014 16:06 IST
In a new discovery, researchers have found that lasers can safely replace years old quartz technology used in wristwatches or to transmit reliable signals to radios.
In lieu of a crystal, researchers at California Institute of Technology (Caltech) have developed a method to stabilise microwave signals in the range of gigahertz using a pair of laser beams as the reference.
"Our new method reverses the architecture used in standard crystal-stabilised microwave oscillators - the 'quartz' reference is replaced by optical signals much higher in frequency than the microwave signal to be stabilised," explained Kerry Vahala, a professor of information science and technology and applied physics at Caltech.
Nearly all electronics require devices called oscillators that create precise frequencies.
For nearly 100 years, these oscillators have relied upon quartz crystals to provide a frequency reference.
Quartz crystals "tune" oscillators by vibrating at relatively low frequencies - those that fall at or below the range of megahertz, or millions of cycles per second, like radio waves.
However, future high-end navigation systems, radar systems and even consumer electronics will require references beyond the performance of quartz.
In the new method called electro-optical frequency division, the optical reference used by researchers is a laser that looks like a tiny disk.
"At only six mm in diameter, the device is very small, making it particularly useful in compact photonic devices - devices powered by photons instead of electrons," said co-author Scott Diddams, a physicist at Maryland-based the National Institute of Standards and Technology.
The study appeared in the journal Science.


text:
BSE in Northern Ireland: epidemiological patterns past, present and future.
Ferguson NM., Ghani AC., Donnelly CA., Denny GO., Anderson RM.
By 30 January 1998, there had been 170,259 confirmed cases of BSE in Great Britain (GB), 1766 confirmed cases in Northern Ireland (NI) (2 January 1998), and 276 confirmed cases in the Republic of Ireland (31 January 1998). Analysis of the epidemiological patterns in the NI epidemic reveals significant clustering of cases in herds and counties. The observed clustering of cases within herds results in lower per capita incidence of BSE in previously unaffected herds, providing support for the introduction of a certified herd scheme in NI. By fitting a backcalculation model to the case data, we can estimate the number of animals infected with the aetiological agent of BSE and project the number of future cases. We predict that the epidemic will decline rapidly, with approximately 99 cases (95% confidence interval 30,504) occurring in the five year period _PHONE_.


text:
Using prepared statement is favorable in two regards: It is more efficient than direct execution of SQL code, since a statement that is used repeatedly needs to be parsed, analyzed, and, optimized only once. This can lead to a significant performance gain, depending on the complexity of the statement. Secondly, since no user input is used to create the SQL statement, but parameters are only passed as function arguments when the statement is executed, SQL injection is effectively prevented.
So here is a short example of how to use this from Lua using the luapgsql interface.
First, connect to a database:
local conn = pgsql.connectdb('')
Using a prepared statement is a two step process. First, the statement needs to be prepared. This is done only once per connection using the prepare() function.
When preparing a statement, use $1, $2, $3 in the SQL code as placeholders for the actual data parameters, which will be supplied later, when the statement is being executed. To give PostgreSQL an idea which data types you will be using you have to supply "example" parameters to the prepare() function. The value of the parameter will be ignored, it will only be used to determine the data type. In the example below a prepared statement with name'myselect' and one parameter, a string value, is created:
conn:prepare('myselect','select firstname from person where lastname = $1', '')
Now the prepared statement can be used as often as needed using the execPrepared() function, indicating the name of the prepared statement and supplying the actual data values:


Edit Article
Two Methods:By HandBy Machine
If you find yourself face-to-udder with a cow and are having a hard time getting milk from your bovine, it's because milking a cow is not as easy as it looks, especially if using a milking machine. And if the cow is cranky, it can be downright dangerous. Start with step 1 to learn how to milk a cow properly and safely.[[Category
Method 1 of 2: By Hand
 1. 1
 Make sure the cow has a halter and is tied to a sturdy post or held in a stanchion.
 2. 2
 Clean the teats with soapy water or iodine. (Warm water may help coax or "bring down" the milk.) Dry the teats, but don't rub or irritate them.
 3. 3
 Place a bucket underneath the udder. Better yet, hold it between your legs. It takes practice, but this can be done easily and comfortably. This position reduces the chance of the cow kicking over the pail of milk.
 4. 4
 Sit or squat in a position that will allow you to move away quickly if the cow becomes uncooperative. Sitting cross-legged on the ground, for example, is not safe. (See Warnings below.) An ordinary milk stool can be fabricated with two 2x4's cut and nailed to form a "T" - cut to fit your behind and make sure it is low enough to afford comfortable access to the cow's teats.
 5. 5
 Apply a lubricant such as Vaseline to your hands to minimize friction.
 6. 6
 Wrap your warm hands around two of the four teats. Choose diagonal teats (front left and rear right, for example). Or, try the front teats first, then the back pair.
 7. 7
 Squeeze the base of the teat, after gently clamping each teat between your extended thumb and first finger, so that the teat fills your palm as you squeeze down.
 8. 8
 Squeeze down to push out the milk, maintaining your grip on the base of the teat so that the milk doesn't flow back up into the udder. Do not jerk or yank the teats. This motion is performed by sequentially squeezing your fingers from the middle to the pinky to force the milk out. Be gentle yet firm. Keep your eyes peeled for mastitis (see Tips).
 9. 9
 Repeat with your other hand. Most people prefer to alternate (right hand, left hand, right hand, etc.) The downward squeezing motions takes less effort doing it in alternate steps than all at the same time.
 10. 10
 Continue until the quarter that you're milking looks deflated. Experienced farmers can feel the udder to know exactly when all the milk has come down. Often even looking at the quarter just milked can tell you if it's been emptied enough or not.
 11. 11
 Move on to milk the other two teats. If you use the diagonal method, switching sides is not necessary.
Method 2 of 2: By Machine
 1. 1
 Secure the cow in position as outlined above.
 2. 2
 Clean the teats as outlined above.
 3. 3
 Turn on the milking machine and allow it to build pressure.
 4. 4
 Hand-milk each teat a few times to let down the milk and check for mastitis (see Tips).
 5. 5
 Release the pressure so that suction begins.
 6. 6
 Place each suction device on each teat. This must be done quickly before the machine loses its pressure.
 7. 7
 Wait until the machine draws all of the milk out of the udder, which will become flaccid as described above.
 8. 8
 Remove the suction devices from the teats.
 - Many modern milking machines do not require the milker to manually remove the suction cups. Once one quarter has been milked dry, they automatically fall off, one by one.
 9. 9
 Empty the milk into a pail or similar container.
 10. 10
 Clean the machine. This prevents milk that dries from building up in the machine.
This video demonstrates the hand milk technique.
 - Always approach the cow slowly. Speak in a low voice and gently pat her side so that she knows where you are. Don't make any sudden movements. The idea is to let her know where you are. If you surprise her, she may panic and kick you or step on you.
 - Some cows lift their back leg and kick over the bucket or knock off the suction devices. Keep the handle positioned so you can grab the bucket should she decide to kick the bucket.
 - When milking by hand, be sure to remember that there is no pulling and tugging on teats you see on TV. Just squeeze gently.
 - Cracked teats irritate cows - treat with Bag Balm (lanolin.)
 - Some cows only stand still if they're given grain or hay to munch on while you go about your business. If your cow is demanding, keep an eye on her food. Be ready to replenish it, or else she'll let you know she wants more by becoming restless and difficult to work with.
 - If you're milking by hand and haven't experienced doing it on a daily basis, your hands will get tired. A single cow can generate 10 gallons (37.9 L) in one sitting. You can take a break but you run the risk of the cow getting impatient and fidgety (not good.)
 - Some people prefer to use udder cream on their hands as they milk.
 - Tying the cow's tail to her leg will prevent her from swishing you with it. Tail hair does not tie well, and it will come loose after a few minutes.
 - The stream of milk that squirts out should be solid. If it's split, as if there's an obstruction in the milk duct, the cow might have mastitis, which will need to be treated. If mastitis is suspected, shoot the first few streams into a fine strainer and look for clumps. If there are clumps, seek appropriate treatment. The clumps can look like giant globs of snot.
 - If you have an ornery cow, she's smarter than you and will delight in taunting and frustrating you. Keep your cool and outsmart her.
 - Kids can practice by "milking" a latex glove filled tightly with water and tied in a knot at the opening. Make tiny holes with a needle at the fingers.
 - If the cow is kicking, try putting your weight into the soft spot on the cow immediately in front of their rear legs. As they cannot bring their leg forward, they cannot kick.
 - If this doesn't work, consider hobbling her or putting a Kow-No-Kick device (or a product with a similar name) on her to teach and prevent her from kicking during milking.
 - Cows kick and they kick hard. They can knock your teeth out and give you a concussion. Be sure you're milking a nice, gentle and well-trained cow, or have experienced supervision.
 - Be careful not to trip over the milking machine's tubes or wires.
 - You may also get smacked in the face (sometimes the eye) by her tail. This is not harmful, but it can be annoying. If this happens, be sure to wash your face and eyes--there's a good chance there's manure and bacteria on the tail.
 - Watch your feet. A cow often weighs over 1,000 lbs. If she steps on your foot, those 1,000 lbs will hurt quite a bit!
 - Cows can kick with a limited sideways motion, as well as directly behind them.
 - Just because the cow's getting milked doesn't mean she has good manners. Don't be surprised if she drops a "cow pie" in the middle of her milking. Some cows will urinate, as well - watch her back - if it arches, grab the bucket and move back.
Article Info
Categories: Cattle
In other languages:
Español: ordeñar una vaca, Deutsch: Eine Kuh melken, Italiano: Mungere una Mucca, Português: Ordenhar uma Vaca, Français: traire une vache, Русский: доить корову, 中文: 挤牛奶, Bahasa Indonesia: Memerah Sapi
Thanks to all authors for creating a page that has been read 252,642 times.
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text:
Dr Julian Lewis and his team at the London Research Institute figured out that Mind Bomb must be playing an important role in the Notch signalling pathway, which helps to tell cells what fate to adopt, or what job to do.
As you might expect, there are versions of Mind Bomb in a host of other organisms, including mammals, where it's involved in making sure the brain and nervous system develop properly. Earlier this year, scientists showed that Mind Bomb also plays a role in the adult mouse brain, and is essential for helping to create long-term memories. Mind Bomb is also the name of a pretty lethal cocktail made with pure alcohol of the kind you would find in a molecular biology lab. Don't try this one at home!


and
 2. Repeat the same procedure for other arrays (Items) if more than two elements exist in it?
Hi,
As we are using UNWIND, we can join different items and create relationships accordingly. So with the following updated Cypher query, we can traverse through the items we previously UNWIND:
CALL apoc.load.json("file:///json_example.json")
YIELD value
UNWIND value.my_links as l
UNWIND l.Items as item1
UNWIND l.Items as item2
MATCH (e1:Entity), (e2:Entity)
WHERE item1.my_code > item2.my_code AND e1.my_code = item1.my_code AND e2.my_code = item2.my_code
CREATE (e1)<-[r:OR]-(e2)
RETURN e1, e2, r
On the other side, annswering to your latest questions, you can also use FOREACH if you need to iterate per some elements.
Hope it helps.
It is working now! Thank you so much. Your quick response is highly appreciated


text:
Administrators will use this section to manage any services and applications that are connected to the SmarterTrack installation, including live chat translations, external feeds, ticket transferring across SmarterTrack instances and more. To access this section, log into the management interface with an administrator account. Then click on the Settings icon. In the Configuration area of the navigation pane, click on Connected Services. The settings will load in the content pane and the following tabs will be available:
Use this tab to edit the following settings:
- Max External Feed Articles - The number of articles that will be displayed per external feed. For example, if an external feed is configured to show blog posts on the SmarterTrack portal, only this number of articles will be displayed at a time.
- Map Provider - Using Google Maps, SmarterTrack can display customer location information in Who's On or when an IP address is clicked in a live chat. To enable a map provider, select Google from the dropdown menu.
- API Key - A Google Maps API Key IS REQUIRED in order to use Google as the map provider in SmarterTrack. Getting an API key is free, and, in most cases, using a standard API key will be fine. However, in larger installations, it may be necessary to upgrade your API key to avoid hitting the limitations applied to a standard API license from Google. For more information on obtaining an API Key, see the Get API Key page. Information about Google Maps Usage Limits is also available from the Google Maps API documentation.
- Translation Provider - Select which translation service to use from the list: Google or Azure. By default, the auto-translation method is set to None.
- API Key - For Google Translator only. The API key provided by Google. For more information on obtaining this key, please see the KB Automatically Translate Live Chats.
- Subscription Key - For Azure Translator only. A security key that allows Microsoft Translate to interact with your SmarterTrack installation. For more information on obtaining this key, please see the KB Automatically Translate Live Chats.
- Requests to Translations API - The total number of translation requests sent to the Translation Provider selected. This allows you to know how many requests sent so any limits can be protected.
- Characters to Translations API - This is the total number of characters sent to the Translation Provider selected. This allows you to keep track of any character limitations imposed by the Translation Provider to avoid any unnecessary extra charges.
- WHMCS Username - Provide the username of an admin-level user within WHMCS who has API Access. (Used when integrating SmarterTrack with the WHMCS Addon Module.)
- WHMCS Password - Provide the password associated with the admin username. (Used when integrating SmarterTrack with the WHMCS Addon Module.)
- WHMCS API Key - This is a security feature used to authenticate the integration between SmarterTrack and WHMCS. Enter the exact API Access Key that is configured in the configuration.php file found within the WHMCS directory. For example, if the following line is present in the configuration.php file: $api_access_key = "abc123", enter abc123 in this field. (Used when integrating SmarterTrack with the WHMCS Addon Module.)
- WHMCS URL - Provide the complete URL of your WHMCS control panel. (Used when integrating SmarterTrack with the WHMCS Addon Module.)
The follow options are available from the content pane toolbar:
- Save - Saves the changes made to the options on the tab.
- Test Settings - Use this button to test your translation settings with the appropriate provider.
- Reset Statistics - This button will reset the character count that is tracked for character conversions using the appropriate translation service. This can be used to check against any reports received or viewed at the translation service website to ensure both systems are in sync.
External feeds allow users to have custom RSS feeds, and snippets of the information in articles or news items, displayed on their portal. External Feeds are different than Custom Links in that the feed snippet is displayed on the Portal home page as a section of the Portal. Custom Links create a new button on the Portal home page.
If any external feeds are available, they will be listed on this page. Otherwise, new feeds can be added by clicking Add in the content pane toolbar. External feeds can be associated with all brands or used and customized on a per-brand basis. Furthermore, if multiple feeds are to be displayed on a brand's portal, they will be displayed in order of how they are listed in the Connected Services settings. Use the Move column to adjust the order of the external feeds, if needed.
Administrators can use this section to connect to another SmarterTrack installation for ticket transferring. This can be useful for those organizations working out of separate locations or across sister-companies. When a SmarterTrack installation is connected, agents can choose whether to transfer tickets to the local or connected instance. Note: Both installations must be running the same version of SmarterTrack in order for this feature to work properly.
To add a SmarterTrack instance, click Add in the content pane toolbar. A modal window will display the following options:
- Connection Name - The friendly name of the SmarterTrack instance.
- SmarterTrack Base URL - The URL for the SmarterTrack portal.
- Admin Username - A system administrator's username for the SmarterTrack instance.
- Admin Password - A system administrator's associated password for the SmarterTrack instance.
(c) 2002-2022 SmarterTools Inc.


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Difference in Maximum VCO and Output Frequencies of CY7B9945V | Cypress Semiconductor
Support & Community
Difference in Maximum VCO and Output Frequencies of CY7B9945V
Last Updated: April 11, 2014
Question:
Why the maximum output frequency is 200MHz when the VCO frequency can go upto 800MHz in CY7B9945?
Answer:
Although CY7B9945V VCO goes up to 800 MHz, there's always a divide by 4 internally (not shown in data sheet), so the maximum frequency to divide is 200 MHz. So CY7B9945V has an internal divider.
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Throttle Modes
From Train Control Systems Documentation
Jump to navigation Jump to search
Overview
Check out our video overview of all of the Throttle Modes available in TCS WOWSound, or continue reading for detailed descriptions of each mode individually
Prototype Throttle Mode
Proto Notch
Proto Notch™ is the TCS exclusive approach to matching the motive power sounds of your model locomotive with the prototype. Using our advanced BEMF motor algorithm, Proto Notch™ decoders can sense exactly how much force is being applied to the rails to move your locomotive and train. By matching that information with prototype performance, we can scale the effort of the model to the real thing and play the right sound to match the work being done.
WOWDiesel
WOWDiesel decoders are configured with diesel-specific prototypical notching. The WOWDiesel decoder selects which notch (1-8) the prototype locomotive would have to be in to haul your scale load at your scale speed. Then it plays the corresponding prime mover sound to emulate the correct power for that notch.
WOWSteam
WOWSteam decoders are configured with variable chuff intensity to emulate prototypical throttling. Your locomotives will make faster and harsher chuff sounds as you ramp up speed or increase the load, and soften to slower and smoother chuffs under lighter loads and less pressure. When the locomotive is coasting, rod clanks and snifters also activate depending on coasting rate and track grade.
The video below can teach you all you need to know about Prototype Throttle Mode:
WOWDiesel Auto Notching
TCS brought auto notching to the model train hobby with the advent of the very first WOWDiesel decoder. It is arguably the coolest feature of the WOWSound decoder!
Auto notching is only available in the Prototype Throttle Mode. Auto notching allows the decoder to sense the load it is under, and decide what notch to be in. Auto notching is unlike Traditional Throttle Mode where the active notch is based exclusively on the speed. With Auto notching the prime mover sound is constantly changing as it goes up hills, around curves, picks up more cars, and coasts down hills!
In order to make the best use of auto notching, you must calibrate the locomotive in Audio Assist® so it knows what the ruling grade is on your layout and will be in notch 8 as it traverses it. Every locomotive is different, both in the sense of unqiue characteristics of the motor and gearing, as well as the "normal" operating conditions in which you run it. All of these factors need to be accounted for, and thus a calibration is needed in order for the decoder to "learn" your railroad.
To calibrate your WOWDiesel locomotive so that it knows the ruling grade and downhill grades on your layout enter Audio Assist® and go to the calibration menu (menu 3.2) and follow the audio prompt from the decoder. It will ask you to run the locomotive in a coasting condition and then a notch 8 condition. (PRO TIP: While on the calibration menu you can calibrate the coasting point by pressing function 1 or the notch 8 point by pressing button 2, even if the menu is telling you to do otherwise)
Behind the scenes Audio Assist® is saving the calibration data to indexed CV4:17 BEMF Calibration Low and CV4:18 BEMF Calibration High both CV's can be programmed tweaked manually. TCS recommends calibrating using Audio Assist® and then manually tweaking the CV's if need be.
WOWSteam Auto Chuff Intensity
WOWSteam Auto Chuff Intensity
Other Prototype Throttle Mode Features
In Prototype Throttle Mode, the default momentum values are set to the "Mainline Momentum" values stored in the decoder as part of the Momentum Modes feature. The Mainline Momentum values are typically high momentum values which create a more realistic operating experience. The higher momentum values require you to use the Train Brake to slow down your train, rather than simply using the speed control on your throttle.
Traditional Throttle Mode
Traditional throttle mode is how sound decoders of the past would "traditionally" operate, where the chuff intensity was one constant volume, or the prime mover notch is related directly to the speed. E.G. every (n) speed steps (of 128 speed steps) is a different notch, so the faster you go the higher the notch you will be in.
See the video below for a demonstration of Traditional Throttle Mode:
Configuration Options
Traditional throttle mode can be selected though and can be selected using Audio_Assist® menu 4.1. Both WOWSteam and WOWDiesel support Traditional Throttle Mode.
(WOWDiesel ONLY): The speed setpoints that the prime mover changes notches are controlled by CV165 through CV172 - where CV165 controls when the locomotive goes into Notch 1 and CV172 controls what speed step the locomotive goes into Notch 8.
(WOWSteam ONLY): To adjust the volume of the Chuff while in Traditional Throttle Mode, you need to change the volume level for the sound type "Chuff." This can be done easily through Audio Assist®. Note that making this change to the Chuff volume type will affect the maximum volume that the Chuff can reach when in Prototype Throttle Mode.
Other Traditional Throttle Mode Features
When you select Traditional Throttle Mode, the momentum values are set to the "Switching Momentum" values stored in the decoder as part of the Momentum Modes feature. The Switching Momentum values are typically low momentum values which disregard realism in favor of a "snappy" and "slot-car-like" operating experience which closely ties the speed of the locomotive to the speed on your handheld throttle. While it is still possible to slow down your locomotive using the Train Brake, it is not a requirement with Traditional Throttle Mode. That said, you can use the Momentum Modes feature to switch back to Mainline Momentum in case you only want to have the notching or chuff intensity be constant but the momentum be realistic.
Manual Notching Throttle Mode (WOWDiesel)
WOWSound from TCS is the original "Full Throttle" diesel decoder. We call it "Manual Notching" but the feature is essentially the same. Manual notching is available on every WOWSound diesel decoder ever made, beginning with Version 1 released back in January of 2015, as part of our overall Proto Notch™ experience.
What is Manual Notching?
Manual Notching allows you to independently adjust the prime mover sound or "notch sound", and separately control the speed of the locomotive. Real life locomotives can be set in notch eight but operating at slow speed because of a heavy train and steep grade. Your TCS decoder by default is configured to Prototype Throttle Mode, giving you the correct load-based sound!
Manual Notching is for users who like to run prototypically without letting the decoder have all the fun of Auto Notching. If you'd like to move notch sounds manually, there are two modes: Semi-Manual Notching and Full-Manual Notching.
The main advantage of TCS' Manual Notching, when compared to many other implementations by other manufactures, is that with a WOWSound decoder you can completely separate the locomotive physical speed and RPM while still retaining complete control of both simultaneously. Additionally, entering and exiting manual notching is simple. Continue reading to learn more.
How do I use Manual Notching?
Using the throttle, you set the desired speed of the loco, and by using the Manual Notch up (default button 10) and Manual Notch down (default button 11) you can change the notch sound to the desired notch. Yes it is that simple! The notch sound you manually select locks in and overrides the current throttle mode's selected notch setting.
Semi-Manual Notching
The manual notch buttons are always active regardless of which Throttle Mode is selected; however, when not in the Manual Notching Throttle Mode, manual changes are overridden when a speed change is made. For example if you are in Traditional Throttle Mode and running down a hill you may want to manually notch down, and then when you reach the bottom of the hill, changing the speed will revert the notch back to what it was before going down the hill. (Note that this is the behaviour you would observe when in Prototype Throttle Mode.) While in manual notch mode speed changes do not override the manual notch setting.
With semi-manual notching active, when you change the throttle the decoder automatically takes back control and sets the appropriate notch sound as determined by the active throttle mode. Ergo, the notching will return from manual to autpomatic if you change the speed of the locomotive.
Full Manual Notching
With the Manual Notching Throttle Mode active, you can manually select the notch by pressing the notch up or notch down buttons. Meanwhile you can still control the speed as your normally would without affecting the active notch setting. This gives full control of both the speed and notch to you simultaneously and completely independently! With full manual notching active, the decoder does not take back over the selected notch when you change the throttle. You remain in full control of the selected notch at all times. To override the decoder's selected notch setting simply use the Manual Notch up and down buttons at any time. Manual Notching overrides the automatically selected notch sound. You can notch up before you even move the locomotive!
Can I remap the Manual Notching buttons?
Yes. By default, TCS "Manual Notch Up" is button ten, and "Manual Notch Down" is button eleven; however, if Manual Notching is something that you would like to use often then we recommend you re-map the


I've implemented a finder using weblogic 8.1 sp2 on win2000 utilizing
Pointbase as my database and the driver is the
com.pointbase.jdbc.jdbcUniversalDriver. The datatype for the active
column is BOOLEAN. I am receiving an exception "EXCEPTION: 25007
Illegal cast operation between type: BOOLEAN and type: DECIMAL" when
the finder executes the following example EJB-QL. It appears that
somewhere deep in the bowels of weblogic the value "true" is converted
to "1".
Example EJB-QL: SELECT OBJECT(a) FROM MyObject a WHERE a.active = true
Any suggestions,
Richard Wallingsford


How to create a population pyramid
A population pyramid shows the distribution of various age groups in a population, for men and women. It's a great way to communicate the age distribution; to see, e.g., that a country has a very young or very old population. It's a common chart type, so most readers won't have problems reading this chart type.
In this tutorial, we will create a population pyramid with Datawrapper's split bar chart.
There are four steps in each Datawrapper chart creation pipeline: Upload Data, Check & Describe, Visualize and Publish & Embed. We will go through all of them:
1
Upload data
In this first step, you can copy & paste data from Excel or the web, or upload your own CSV files. Here is a part of the data for our chart up there:
Age span Male Female
95-100 34000 138000
90-95 213000 490000
85-90 619000 _PHONE_
80-85 _PHONE_ _PHONE_
... ... ....
20-25 _PHONE_ _PHONE_
15-20 _PHONE_ _PHONE_
10-15 _PHONE_ _PHONE_
5-10 _PHONE_ _PHONE_
<5 _PHONE_ _PHONE_
Note how the data set should be structured:
 - One header row containing labels ("Age span", "Male" and "Female").
 - The first column defines the age buckets ("15-20", "20-25", etc.). Alternatively, years or single ages work.
 - The second and third column contains the number of people in this age bucket, for males and females. This number can be absolute, like in our cases, or relative (shares of the population).
This is how the data looks like once we copied it in step 1, Upload Data:
After finishing this step, click "Proceed" to get to the second step, Check & Describe:
2
Check & Describe
Here, your data should look like above. If your first column contains dates (like years, days, weeks), Datawrapper will tell you that it detected the data format and will color it green. Numbers will appear in blue. To learn more about data column type detection, visit this article.
Finally, make sure that the box "First row as label" is ticked so that Datawrapper correctly assigns the values to the labels. Click on "Proceed" and Datawrapper will take you to the next step:
3
Visualize
In this step, you can see four tabs. In the first tab, "Chart type", we see a grid of chart types. To create a population pyramid, we want to choose the chart type "Split Bars":
In the second tab, "Refine", we can configure our chart; e.g., we can change the colors of the bars To learn more about each feature, visit the article "Customizing your split bar chart". Here we will talk only about the settings that will define a population pyramid:
First, you want to make sure that the number format works best for this chart. You can find the number formatting in the panel "Labeling". If you have very high population values, choose the number format "123.45k" or "123.4k". In case your pyramid shows population shares, choose the format "0%" or "0.0%".
But our pyramid still doesn't look like a pyramid. To change that, we want to go to the next panel, "Appearance", and "Mirror Bars":
You can also play around with the space between the columns. Maybe you prefer no space between the male and the female numbers at all? We also turned on the bar background, to give the whole chart a less cluttered appearance.
Finally, we changed the custom range in the last panel, so that the bar background appears even for the highest value. Extending the custom range gives the whole chart a more tidy look:
In the last two tabs, you can add annotations and choose the design for your chart. Visit the article "Customizing your split bar chart" to learn more about these features.
Click on "Publish" to get to the last step, "Publish & Embed".
4
Publish & Embed
Congratulations to your finished population pyramid! In this last step, you can publish your work and decide how to share it with the world. The best way to use a Datawrapper chart is by embedding it directly on your website. To do that, click the big blue button that says " Publish Chart". Then, copy & paste the embed code snippet into your website or CMS. You can also download your chart as a PNG or PDF by upgrading to a paid Single or Team account.
Still need help? Contact Us Contact Us


text:
A GROUND-breaking primary school has won three architectural awards.
Sandal Magna Community Primary School won the awards at the Royal Institute for British Architects (RIBA) Northern Network Awards.
The 210-pupil eco-school, which opened in September 2010, won the Northern Network Gold Award, the Category Award for Sustainability and the Project of the Year: White Rose award.
The school is one of the most carbon-efficient schools in the country and has a design based on the nearby housing and factory chimneys.
It was built by Sarah Wigglesworth Architects.
Headteacher Julia Simpson said: "Having occupied this exciting learning environment for 15 months it is gratifying to see how well the building is working for our children and their families.
"The staff and governors are delighted that their partnership with Sarah Wigglesworth Architects and the local authority has resulted in an eco-school which is regarded as an exemplar project both regionally and nationally."
The school was built to replace the previous Victorian building, and many of the old bricks from the original structure are used in the gardens.
The school also has outdoor spaces for planting, quiet games and learning and it's building has been used to teach the pupils about the environment and sustainability.


text:
Skip the mid-term in history: U of T students adopt 200 year old diets from Southeast Asia
November 30, 2016
In HIS346H Rice and Spice in Southeast Asia: a Regional Food History, Professor Nhung Tran teaches her undergraduate students through an experiential learning project. After choosing from a list of people living in different regions of Southeast Asia during the seventeenthand nineteenthcenturies (e.g. Javanese sugar factory worker), students then research and adopt the diet of that person for four days. To learn more about students' experiences on diets of rice, sweet potatoes and fish, read further here: Faculty of Arts & Science News.


united states | resilience
The strength and skills to cope when adversity hits home.
Children's Education Initiatives in United States | Finding strength in the face of adversity
Challenges, big and small, are part of life. Whether it's a playground conflict, bullying, or life-changing experiences such as a family member's divorce or imprisonment, the pressure and anxiety these experiences inflict can be overwhelming for a young child. That is why Sesame Workshop is extending a furry hand to vulnerable children confronting these and other tough situations.
Featuring the lovable cast of Sesame Street, our Child Resilience Initiative gives children ages 2 to 5 and their families valuable education and skills to cope with adversity at home and school. Developed with input from psychologists and child-development experts, this multimedia toolkit is designed to bolster kids' sense of self, help them develop positive conflict resolution skills, and express their feelings in positive ways. Armed with these skills and the secure support of adults, children can find the strength to face everyday challenges and whatever else life may bring.


Take the 2-minute tour ×
I need to update the Notes field in my table tblMain by concatenating the text data with the Notes field in my secondary table tblSecond by matching the ID field in both tables.
I was using the following SQL:
UPDATE tblMain
SET tblMain.Notes = (tblMain.Notes + (SELECT DISTINCT Notes FROM tblSecond
WHERE tblSecond.ID = tblMain.ID))
but I get the following error
Subquery returned more than 1 value.
presumably because the SELECT statement is returning an entire resultset.
How would I perform this operation successfully?
share|improve this question
I just tried it again using a MERGE MERGE INTO tblMain USING ( SELECT ID, notes FROM tblSecond ) Second ON (Second.ID = tblMain.ID) WHEN MATCHED THEN UPDATE SET tblMain.Notes = tblMain.Notes + Second.notes but I get a similar error: The MERGE statement attempted to UPDATE or DELETE the same row more than once. This happens when a target row matches more than one source row. A MERGE statement cannot UPDATE/DELETE the same row of the target table multiple times. Refine the ON clause to ensure a target row matches at most one source row, or use the GROUP BY clause. – mechaman64 Jun 28 '12 at 10:47
I assume in the tblSecond table you can have multiple notes for a single record in tblMain? In other words, it may be possible to concatenate multiple records from tblSecond into a single tblMain record? – LittleBobbyTables Jun 28 '12 at 10:48
If there are two rows in Second that correspond to one row in Main, are you looking to concatenate both rows into Main? – Triple Gilaman Jun 28 '12 at 10:50
2 Answers 2
up vote 1 down vote accepted
It will handle if subquery returns more than 1 value.
UPDATE tblmain
SET tblmain.notes = ( tblmain.notes
 + (SELECT DISTINCT notes +''
 FROM tblsecond
 WHERE tblsecond.id = tblmain.id
 FOR xml path ('')) )
share|improve this answer
This works perfectly - thanks! – mechaman64 Jun 28 '12 at 14:05
If the subquery returns more than 1 value, it means that tblSecond contains more than 1 entry for the corresponding ID. So I would suggest to first check your data.
The update itself can also be written using the from clause, something like this (untested)
update tblMain
 set Notes = a.Notes + b.Notes
 tblMain a
 inner join tblSecond b on a.Id = b.Id
share|improve this answer
tblMain will have the only last value that was concatenated to notes. – Romil Jun 28 '12 at 10:59
_USER_ thanks for pointing out. – mfussenegger Jun 28 '12 at 11:02
either correct the post or delete because it will create confusion for other readers. it will help you to avoid downvoting also. – Romil Jun 28 '12 at 14:07
Your Answer


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Knowledgebase: Performance Tuning
Best Practices for improving the performance of large collection deletes
11 March 2022 03:37 PM
Introduction
This article outlines various factors influencing the performance of xdmp:collection-delete function and furthermore provides general best practices for improving the performance of large collection deletes.
What are collections?
Collections in MarkLogic Server are used to organize documents in a database. Collections are a powerful and high-performance mechanism to define and manage subsets of documents.
How are collections different from directories?
Although both collections and directories can be used for organizing documents in a database, there are some key differences. For example:
 - Directories are hierarchical, whereas collections are not. Consequently, collections do not require member documents to conform to any URI patterns. Additionally, any document can belong to any collection, and any document can also belong to multiple collections
 - You can delete all documents in a collection with the xdmp:collection-delete function. Similarly, you can delete all documents in a directory (as well as all recursive subdirectories and any documents in those directories) with a different function call - xdmp:directory-delete
 - You can set properties on a directory. You cannot set properties on a collection
For further details, see Collections versus Directories.
What is the use of the xdmp:collection-delete function?
xdmp:collection-delete is used to delete all documents in a database that belong to a given collection - regardless of their membership in other collections.
 - Use of this function always results in the specified unprotected collection disappearing. For details, see Implicitly Defining Unprotected Collections
 - Removing a document from a collection and using xdmp:collection-delete are similarly contingent on users having appropriate permissions to update the document(s) in question. For details, see Collections and Security
 - If there are no documents in the specified collection, then nothing is deleted, and the function still returns the empty sequence
What factors affect performance of xdmp:collection-delete?
The speed of xdmp:collection-delete depends on several factors:
Is there a fast operation mode available within the call xdmp:collection-delete?
Yes. The call xdmp:collection-delete("collection-uri") can potentially be fast in that it won't retrieve fragments. Be aware, however, that xdmp:collection-delete will retrieve fragments (and therefore perform much more slowly) when your database is configured with any of the following:
What are the general best practices in order to improve the performance of large collection deletes?
 - Batch your deletes
 - You could use an external/community developed tool like CoRB to batch process your content
 - Tools like CoRB allow you to create a "query module" (this could be a call to cts:uris to identify documents from a number of collections) and a "transform module" that works on each URI returned. CoRB will run the URI query and will use the results to feed a thread pool of worker threads. This can be very useful when dealing with large bulk processing. See: Using Corb to Batch Process Your Content - A Getting Started Guide
 - Alternatively, you could split your input (for example, URIs of documents inside a collection that you want to delete) into smaller batches
 - Spawn each of those batches to jobs on the Task Server instead of trying to delete an entire collection in a single transaction
 - Use xdmp:spawn-function to kick off deletions of one document at a time - be careful not to overflow the task server queue, however
 - Don't spawn single document deletes
 - Instead, make batches of size that work most efficiently in your specific use case
 - One of the restrictions on the Task Server is that there is a set queue size - you should be able to increase the queue size as necessary
 - Scope deletes more narrowly with the use of cts:collection-query
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text:
Volume 15 (2017) Issue 8 Pages 397-406
This study presents a new bond model based on the deterioration mechanisms observed during uniaxial tensile tests of reinforced concrete prismatic specimens subjected to freeze-thaw cycles. The test results demonstrated that the bond stress reduced, even though the specimens were exposed only to temperature fluctuation without the damage in concrete cover. The proposed model considers the bond deterioration mechanism caused by the temperature fluctuation in addition to the damage in concrete cover. Finally, the proposed model shows good agreement with the test results regardless of the dominant deterioration mechanism.


text: Marian is a suburban town located in the local government area of the Mackay Regional Council in the state of Queensland. The town's name was taken from the non-operational Marian railway station, which was thought to be derived from the name of a local property known as Mary Ann. Among the oldest structures in the suburb include the Marian Mill Post Office that has been open since January 1, 1909. Its name was later changed to Marian in 1910. A museum that features the historic Melba House and the Pioneer Valley Visitor Information Centre are also found in Marian. The Marian sugar refinery plant, which is one of the biggest sugar refineries in Australia, is also located in the suburb.


text:
h beam iron steel i beam
A36 Hot Roll Steel I Beam. Standard beams are produced to A36/SA36. Wide flange is dual certified grade 50 to A572 and A992. Junior beams are certified to A36/SA36. Hot Roll Steel I Beam Sizing is depth in inches by pounds per foot.
Made of stiff low-carbon steel to deflect less under load, these H-bars are commonly used in machine bases, construction, platforms, and frames. Because of its rigidity, low-carbon steel is the most commonly used material for H-bars. These H-bars are less likely to crack from welding than those made of higher-carbon steels, and easier to weld than I-beams because they have a straight flange H-Beam vs I-Beam:What's the Difference? Tampa
- What Is An H-Beam?
H-beam vs I-beam Steel (14 Difference Analysis)
- I-Beam Steel Metals Depot® - Buy Steel Beams Online!Commonly termed an I Beam because of its shape, beams provide great load bearing support when used horizontally or standing as columns. Available in two configurations, the most popular being the Wide Flange Steel Beam aka H Beam or W Beam with non-tapered flanges.


3
Selecting an anchor link with content, such as test link, I can see three different ways to do it using XPath:
a[text()="test link"]
a[.="test link"]
a[contains(text(), "test link")]
What are the differences between the three? The last option appears that it would take longer by virtue of it being an extension of the first.
3
You can find an Xpath specification here. Your first xpath matches an anchor that contains exactly the string "test link". The last xpath matches an anchor whose contents includes the substring "test link". No doubt it is slower, but the depending on the circumstances, the performance difference may be insignificant.
As far as I can tell, the first and second xpaths are equivalent.
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Sending the response message of API after command success or failed
I using the constructor of aggregate with command handler annotation, to create create the new instance of the aggregate. Now after the creation, the api have to send the response message to UI (which shown to user). How I can achive this? and what is the best way to to this?
I was learned about the following pattern,, please suggest any good way or example to implement this.
In simple cases your API endpoint handler can construct a command and use sendAndWait() to send the command via the command gateway.
sendAndWait will throw an exception if the the command was not dispatched successfully.
The issue is that your projections will not necessarily be up to date on return from sendAndWait() – so you can't "read your writes".
There is a discussion on the "read your writes" issue here
It has some sample code.
In our project we have built on the understanding gained from the sample code to create an implementation pattern of correlated commands and events.
Our projections publish on the query bus to allow senders of correlated commands to know when their write is readable.
It's working well and is a surprisingly small amount of code.
From the link above it sounds like Axon will provide something like this at some point…
Hi Aswani, Steven,
Aswani, what kind of response are you looking for to be returned as part of a command execution?
The framework does not impose any restriction on returned values from Command Handlers at the moment.
However, from a usage perspective we suggest that you only return a void (in case of success or ignore), an exception (for failure) and Identifiers of Aggregates/Entities which were constructed as a result of handling the command.
A command handling constructor will actually by default provide you with the Aggregate Identifier, instead of the Aggregate instance.
Thus, if the response you'd want to give to the UI is an identifier to be able to retrieve a query model, this should already be doable.
What Steven points out should also proof valuable, given the scenario you need to reply with an actual Query Model, spoofing a synchronize operation on the back-end.
I think his suggestion would be sufficient given you're interested in the entire Query Model.
Lastly, as pointed out, we're indeed looking into adding the some indication in the Command Response pointing to the sequence of the last event published as a reaction to the given command.
With this, you should in turn be able to query your model adding this sequence number to the query you dispatch as an expectation your Query Model should comply too.
As shared, this is however not yet implemented.
That's my 2 cents to the situation.


A methodology for designing pumps to meet multi-objective design criteria is presented. The method combines a 3D inviscid inverse design method with a multi-objective genetic algorithm to design pumps which meet various aerodynamic and geometrical requirements. The parameterization of the blade shape through the blade loading enables 3D optimization with very few design parameters. A generic pump stage is used to demonstrate the proposed methodology. The main design objectives are improving cavitation performance and reducing leading edge sweep. The optimization is performed subject to certain constraints on Euler head, throat area, thickness and meridional shape so that the resulting pump can meet both design and off-design conditions. A Pareto Front is generated for the two objective functions and 3 different configurations on the Pareto front are selected for detailed study by 3D RANS code. The CFD results confirm the main outcomes of the optimization process.
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text:
Mary Dixon Kies
Born 1752 - Died 1837
Weaving Straw with Silk or Thread
Patented: May 5, 1809
Mary Dixon Kies was the first woman to apply for and receive a U.S.
patent in her own name. Her patent, issued May 5, 1809, was for a
process for weaving straw with silk that was adopted by the New England
Kiesís invention was praised by President James Madison's wife Dolly for
helping to improve New England's economic situation, which had been hurt
by an embargo on goods imported from Europe. New England's hat industry
was one of the few industries that continued to prosper during the War
Kies's patent, which was destroyed in the Patent Office fire of 1836,
was one of only 20 issued to a woman before 1840
Kies was born in South Killingly, Connecticut. Very little is known
about her life or her accomplishments beyond her patented weaving
process, which was widely used for over a decade.


text:
A Smooth Transition
The majority of our students are very familiar with the Holy Family Catholic School by the time they join us in Year 7. As well as Year 6 students moving into the The Holy Family to work on transition projects, our year 7 Acheivement Leader and other members of staff visit schools to meet and work with the children. The staff liaise with the primary colleagues so that we know as much as possible about each child before they join us. In July all prospective Year 7 students spend two days in school taking part in activities and getting to know their future classmates and teachers.


text:
National Wildlife Refuge
|44843 County Road 19
Odessa, MN 56276
Phone Number: _PHONE_
|Visit the Refuge's Web Site:
|Big Stone Refuge was named for its lichen-covered granite outcrops.|
Continued . . . The Project was authorized under the Flood Control Act of 1965. Project purposes included flood control, general recreation, and fish and wildlife habitat. The project was designed to improve the water quality of Big Stone Lake through modifications of the Whestone River silt barrier. It was also designed to provide flood protection benefits to downstream lands along the Minnesota River and resulted in the establishment of extensive wetland areas.
During the early 1970s, the U.S. Army Corps of Engineers constructed a large dam for this project across the Minnesota River, which impounded approximately 5,000 acres of surface water. A water control and spillway overflow structure were installed in the dam to provide for the manipulation of the water levels in the large wetland impoundment. Lands for the project were initially acquired by the Corps of Engineers in 1971, then subsequently transferred to the U.S. Fish and Wildlife Service in fee title during May 1975. All the lands (11,115 acres) acquired by the Fish and Wildlife Service were incorporated into the land base for Big Stone Refuge.
|- Back -|


PigProgress - What to do when tail biting occurs?
What to do when tail biting occurs?
Almost all conventional pig producers will be familiar with tail bitten pigs. It's called a tail biting outbreak when biting leads to multiple victims per pen, or even spreads throughout the barn. Outbreaks are hard to stop – here is how it is possible to overcome an outbreak successfully.
Tail-bitten pigs are often noticed only at an advanced stage, when there is shortening of the tail. At this stage it is likely that most other pigs in the pen have noticed the blood and been attracted to it. That may motivate them to bite and to create new victims.
Ideally, tail biting is noticed at an early stage, before there is blood on the tail and before the tail length is reduced. This can be through either noticing the biter or noticing the victim. When a pig is repeatedly biting tails, the pig can be observed for ten to 15 minutes to see if it continues biting. If this is the case it might be better to remove the potential problem causer.
Ropes are chewable, destructible, somewhat edible. Photo: J-Y. Chou
Tail posture as indicator
Victims can be recognised at an early stage by looking at tail posture. A tail almost permanently tucked between the legs indicates it is being bitten. A briefly tucked tail can, however, be in response to other social interactions such as displacement. A good time to check tail posture is at the feeder. If the feeding is synchronised, it is easy to check all tails together. Even at an individual feeding station, if pigs are constantly seen with tucked tails when feeding, there may be a biting problem in the pen. A tucked tail should be inspected closely; if injuries are present, then it is better to act immediately rather than wait until it gets worse.
Burlap sacks can be used by more pigs simultaneously. Photo: W.W. Ursinus
What to do?
Action to address tail biting can be through providing distraction to the group or by removing biters or victims when it is more severe. Almost anything can be used to distract pigs, but they easily lose interest. It is therefore more important to change enrichment regularly than to necessarily have the best type of enrichment. However, enrichment should be safe for the animals and not pose risks for food safety.
Good enrichment materials for pigs are chewable, destructible and edible and can be manipulated by multiple pigs at the same time. Loose materials such as straw, hay and sawdust are most used by pigs, but if the housing limits the provision of these, there are other alternatives. Examples are ropes, large feed pellets (beetroot pellets), soft rubber hoses and jute sacks (burlap sacks).
What to do when tail biting occurs?
Using a step-wise protocol
Straw is one of the best materials to occupy pigs. However, for several reasons straw may not be a suitable option or possibility, especially on fully slatted floors. In Ireland about 80% of farms have fully slatted floors. A recent study conducted on a farm in Ireland showed that tail-biting outbreaks can still be effectively reduced using a set protocol. In this protocol three types of intervention were used in a random order:
A. Putting three ropes in a pen of 12-14 pigs
B. Removing the victim
C. Removing the biter.
If after 72 hours blood was detected on one of the pigs in the pen, then the next step was taken. When an option was applied but was not successful, then the next one was applied until all three options had been used. Victims or biters that had been removed were later introduced back in the group as described in the protocol in the box. This resulted in no overt aggression between the pigs when the removed pigs were reintroduced to the original group.
Figure 1 – Step wise plan for overcoming tail biting problems in a pen.
What to do when tail biting occurs?
80% of outbreaks can be solved
The study showed that 80% of severe tail-biting outbreaks could be stopped, even when removed pigs are reintroduced to their original groups. Adding ropes could shorten the duration of an outbreak, since it may take longer to remove and reintroduce pigs. Removing victims or biters was as effective as adding ropes in stopping an outbreak. All pigs were reintroduced to their original groups, which saved the need to have extra space to permanently house removed pigs. Based on the outcomes, the following stepwise plan was recommended (see Figure 1).
Figure 2 – The chance of reducing a tail biting outbreak 'likelihood of success' depends on the number of victims and biters per pen.
The need to respond quickly
The results also showed the importance of responding quickly to the occurrence of tail biting. The chance of successfully reducing a tail-biting outbreak depends on the number of affected pigs in the pen. Figure 2 shows that if more than 50% of the pigs are victims of tail biting, the chance of success in overcoming the outbreak can still be around 60%. But if 33% of pigs are biters, then the chance of stopping the outbreak is only 30%. Thus, the more biters in the pen, the smaller the chance that the outbreak can be stopped.
How to remove and reintroduce pigs from a group?
1. Determine which pig to remove to gain most benefit.
2. Remove the selected pig together with at least one other pig.
3. Write down the pen number from which they are removed and date of removal.
4. Provide a recovery pen without mixing with other unfamiliar pigs.
5. When the pigs have recovered, or at least within seven days, return the pigs together to the original pen.
6. Provide ropes in the pen at the time of reintroduction.
7. Use scent marking spray such as diluted Dettol when pigs are returned.
Have a tail-biting first aid kit
This protocol worked successfully at the farm, which is a conventional farm with fully slatted floors. This does not mean that the protocol will be successful under different conditions. We encourage others to try it but to have other safety measures ready as well. We recommend having a stock of different enrichment objects and products that are directly available whenever an outbreak occurs. Such a 'tail-biting first aid kit' can include ropes, straw, toys, large feed pellets (beetroot pellets), rubber hoses and jute sacks (burlap sacks).
By Irene Camerlink, University of Veterinary Medicine, Vienna, Austria and Jen-Yun Chou, Teagasc, Ireland


Why should I Hire a Lawyer if there is a Real Estate Agent or a Mediator involved in my House Purchase?
One of the reason is because the Real Estate Agent is not responsible by law for legal issues or urban verifications in the property purchase in Italy.
The Real Estate Agent's responsibility in Italy is limited to the intermediation work linking the buyer and the seller. This task will be carried out through the normal diligence which simple consists in the performance of aforementioned service referred to a broker with medium capacity.
Therefore, he is not responsible if in the closing phase of the notarial deed he didn't informed and alerted the buyer on the fact that the chosen property was subject to urban issues and that issue wasn't allowing its marketability.
The damages requested to the mediator were huge, in addition to the down payment (Caparra) also the damage for the non-purchase of another property that would have been optioned if the promissory buyer had known from the first moment the urban differences.
Therefore, the mediator has the obligation to inform the parties of the circumstances known to him, all those things of which he became aware in carrying out the assignment, and also of all the circumstances that could have been acquired by a mediator with only medium professional skills, with the use of normal diligence. Definitely, not legal skills or obligations.
However, nothing can be claimed about the responsibility of the Real Estate Agent with regards to the control and verification of the mortgage deeds and the urban situation.
The Italian Supreme Court (Corte di Cassazione) has repeatedly reiterated that in the ordinary diligence is not required that the mediator does any of the technical-legal investigations, such as, for example:
 - the mortgage and land registry surveys;
 - the verification of the urban situation;
 - the assessment and the check in the Real Estate Registers;
 - the freedom of the property subject to negotiation from transcripts or prejudicial registrations;
 - or even the urban planning examination.
In this regard, the same Court refers to a very long jurisprudence composed of dozens of sentences that have affirmed the same principle.
Therefore, the Court condemned the promissory purchasers who had turned to the Real Estate Agent to be compensated for damages above mentioned because of the differences found they could not be part of that level of elementary knowability for which the estate agent would not provide justifications based on his personal lack of knowledge.
Different fate would have had in the case in which the mediator received an express assignment from the promissory buyer (with specific and more expensive remuneration, different from the commission) to carry out mortgage-cadastral or urban planning surveys, his obligation to fulfill the task is clearly outlined, and he could have civil responsibility in the hypothesis that the job was not well done.
It follows that if Real Estate Agents do not check the urban situation, they have no responsibility whatsoever, except that they have failed to communicate the information known, or in any case elementary diligence, while if the Estate Agents received an express assignment with specific and more expensive remuneration he has to provide information of a mortgage-cadastral or urbanistic nature assuming the particular responsibilities of the case, but still he is not a legal professional.
In conclusion, prudence requires to abstain from reckless steps and to delegate everything related to your real estate transactions in Italy to a professional Trusted Lawyer.


Take the 2-minute tour ×
A column of troops one km long is moving along a straight road at a uniform pace. A messenger is sent from the head of the column, delivers a message at the rear of the column and returns. He also moves at a uniform pace and arrives back at the head of the column when it has just covered its own length. How far did the messenger travel?
I can't get any ideas on how to start.
Thanks for any help.
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How far did the messenger travel means the distance traveled or the displacement? If its displacement then the answer should be 1km. – Saurabh Jul 3 '12 at 6:10
It means distance. – Matt Jul 3 '12 at 6:12
You just need to organise the information carefully and use distance = speed x time. Write down what you know about the movement of the column - say speed $u$ and the messenger say speed $v$ taking total time $t$. Split the movement of the messenger into two obvious parts. Then identify the total distance $d$ you want to find, and use the information you have to find an equation for $d$. – Mark Bennet Jul 3 '12 at 6:19
A trivial answer to the question would be $1$km, the length of the column. After all, the messenger starts out at the head of the column, and ends up again at the end of the column, at the point in time when it has covered its own length, and she then has advanced as much as the column has. This is probably not what the question intends, but it could be made clearer. – Marc van Leeuwen Jul 3 '12 at 6:50
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up vote 7 down vote accepted
Let us assume that the speed of the column is $1$ km per unit of time. For convenience, call that unit an hour. The column took $1$ hour to cover its own length.
Let $v$ be the speed of the messenger. When she is travelling to the back, the combined speed of approach of the messenger and the column rear is $v+1$, so the time it takes is $\frac{1}{v+1}$. Going the other way, the speed at which the messenger gains on the head is $v-1$, so the time it takes to gain the whole $1$ km is $\frac{1}{v-1}$. The whole task took $1$ hour, and therefore $$\frac{1}{v+1}+\frac{1}{v-1}=1.$$ This gives $v=1+\sqrt{2}$. The time taken is an hour, so the distance travelled is $1+\sqrt{2}$.
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Let the speed of troop is $u$ kmph and that of messenger is $v$ kmph.
So the relative speed when messenger is going backward is $v+u$ kmph.
And relative speed while going forward is $v-u$ kmph $(v>u)$.
So the total time taken is $$t=\frac{1}{v+u}+\frac{1}{v-u}$$ but in this time troop had moved $1$km so the $t=\frac{1}{u}$
$$\frac{1}{u}=\frac{1}{v+u}+\frac{1}{v-u}$$ $$v^2-2uv-u^2=0$$ which give us the following relation $$v=u(1+\sqrt2)$$
so the distance traveled is $$\begin{align*} d= &\underbrace{\frac{v}{v+u}}_{backward}+\underbrace{\frac{v}{v-u}}_{forward}\\ &=\frac{2v^2}{v^2-u^2}\\ &=\frac{2v^2}{2uv}\\ &=\frac{v}{u}=1+\sqrt{2}\text{ km}\end{align*}$$
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Mostly ok, but why did you give the answer using units of speed? Mind you, I've never seen it abbreviated "kmph". At least locally "km/h" is the only way to write it. This is different from, e.g. U.S.A., where "mph" is always used. I guess there are local variations :-) – Jyrki Lahtonen Jul 3 '12 at 7:27
_USER_ Oh that was a mistake.I have corrected it.Thanks – Saurabh Jul 3 '12 at 7:32
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Let $x$ be the troops' speed and $y$ be the messenger's speed.
Total messenger travelling time is $1/x$ (as the troops moved 1km forward).
In the troops frame of reference, the messenger first moved backwards with the speed of $y+x$, and then moved forward with the speed of $y-x$ so that in the $1/x$ total time he returned to the initial position.
Let $z$ be the time messenger spent to reach the rear of the column. Obviously, $z = 1/(y+x)$ (as messenger moves with the speed of $y+x$ relative to the column and has to travel $1$ km relative to the column to reach its rear).
From the other side, we have $z \times (y+x) + (1/x - z) \times (y-x) = 0$, from which follows $2zx + y/x - 1 = 2/(y/x+1) + y/x - 1 = 0$.
Note that the total messenger travelling distance is $d = y/x$. From the previous equation we get $2/(d+1) + d - 1 = 0$, $d^2-3 = 0$, and thus $d = \sqrt{3}$.
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