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Short Summaries of Articles about Mathematics
in the Popular Press
"The impossible puzzle," by Michael Brooks.New Scientist, 5 April 2003,pages 34-35.
This article reports on a lecture presented by the renowned physicist StephenHawking at the Diraccentennial celebration at the University of Cambridge. In the lecture,en... | <urn:uuid:d4678a9f-d376-4000-9a09-a58f8eb1f104> | 2.84375 | 219 | Content Listing | Science & Tech. | 28.71859 |
Poison: Concurrent Termination
All programs must come to an end. At some point, a program will need to terminate, either because it has finished its task, or because the user has told it to terminate — or perhaps because the program has encountered an unrecoverable error. Especially in the latter two cases (where the t... | <urn:uuid:bace4661-b364-42bb-8b4c-13099829060b> | 3.125 | 2,105 | Personal Blog | Software Dev. | 44.953186 |
Choose a Topic or Enter a keyword to search:
You have selected the following Demos:
Purpose:To show that excess charge resides totally on the outside of an insulated conductor.
Procedure:Charge the metal cylinder by touching it with the Teflon rod (charged with fur or silk) a few times. Show that there is a charge on t... | <urn:uuid:4678a55e-70ef-46ec-9417-60d6cbced8a7> | 3.0625 | 294 | Tutorial | Science & Tech. | 52.593354 |
Boolean values are the two constant objects
True. They are used to represent truth values (although other
values can also be considered false or true). In numeric contexts
(for example when used as the argument to an arithmetic operator),
they behave like the integers 0 and 1, respectively. The built-in
function bool()... | <urn:uuid:0d63a05d-53cf-4d39-8292-1931ad8407a2> | 2.921875 | 116 | Documentation | Software Dev. | 50.790761 |
1. what is the area of a square whose diagnol is 1 unit longer than the length of a side?
2. if a 3 didget number is chosen at random, from the set of all 3 diget numbers what is the probablility all 3 didgets will be prime?
for what value of "b" will the solution of the system consist of pairs of positive numbers?
4. ... | <urn:uuid:b72434e7-eb43-41eb-bd5c-e046ce4b9e6a> | 2.71875 | 167 | Q&A Forum | Science & Tech. | 74.994822 |
Is it possible to reverse global warming?by Cathy Wurzer, Minnesota Public Radio
ST. PAUL, Minn. — July was a very hot month, the 10th straight month that the average temperature in Minnesota was above normal. Is this a preview of the type of weather that will be normal in the future?
There is a lot of evidence that th... | <urn:uuid:e2c9c480-5bb5-43fe-9838-69c73244727e> | 2.765625 | 152 | Truncated | Science & Tech. | 62.784675 |
Ocean Acidification: How Bad Can it Get?
Feely, R.A., Doney, S.C. and Cooley, S.R. 2009. Ocean acidification: Present conditions and future changes in a high-CO2 world. Oceanography 22: 36-47.
Tans, P. 2009. An accounting of the observed increase in oceanic and atmospheric CO2 and an outlook for the future. Oceanograph... | <urn:uuid:e86cd54b-f42c-40f9-ad39-e5ce3654c56a> | 2.953125 | 795 | Academic Writing | Science & Tech. | 55.733183 |
Species at Risk: Leatherback sea turtle
In 1982, scientists estimated that there were 115,000 adult female leatherback sea turtles worldwide. Recent estimates have placed the number between 20,000 and 30,000.
The Pacific leatherback sea turtle is in such severe decline that scientists believe they will become extinct i... | <urn:uuid:9d9e9bd8-80be-4db9-b75e-00d6b8408a01> | 3.75 | 343 | Knowledge Article | Science & Tech. | 38.620636 |
Climate change has become a hot topic in more ways than one, so instead of jumping straight into the issues surrounding sea level rise it’s worth discussing how climate change or global warming can sometimes play out in the news.
Let’s start with something cool, concrete, and agreeable: numbers. Most people would agree... | <urn:uuid:5a678d15-4325-43c1-971f-faed2380e6e2> | 2.84375 | 1,018 | Personal Blog | Science & Tech. | 56.653573 |
Perl 5 is known to have very good Unicode support (starting from version 5.8, the later the better), but people still complain that it is hard to use. The most important reason for that is that the programmer needs to keep track of which strings have been decoded, and which are meant to be treated as binary strings. An... | <urn:uuid:3d63b262-e20c-4f76-af0e-4bbd38c3ac12> | 2.984375 | 552 | Documentation | Software Dev. | 72.093102 |
To detect blood the smell first has to reach the shark.
From The Naked Scientist:
Water molecules in general are carried to the shark by water currents.
If there are no water currents then it is molecular diffusion, the
random movement of molecules that disperses the odour away from the
In general the travel time of od... | <urn:uuid:8b521c31-64f5-445d-9b85-068863462c44> | 3.734375 | 501 | Q&A Forum | Science & Tech. | 52.499636 |
Forget the world, the Sun is not enough. Astronomers have found a planet outside our own Solar System, which has as many as four suns! Yes, this planet, thought to be a gas giant, orbits four different suns.
The planet was discovered by volunteers who were using the Planethunters.org website, which allows enthusiastic ... | <urn:uuid:cbb07255-c182-4060-a72f-03e1215e7f15> | 3.3125 | 459 | Personal Blog | Science & Tech. | 53.02327 |
Summary of 2010 Madison Plateau, Yellowstone Earthquake Swarm
Retrospective analysis shows that the 2010 Madison Plateau swarm began on January 15, 2010 with a few small earthquakes and picked up in intensity on the 17th of January. By the end of February 2010, earthquake activity at Yellowstone had returned to near-ba... | <urn:uuid:3fbb1cd0-9306-49b2-9e77-79c8f5248d75> | 2.984375 | 1,818 | Knowledge Article | Science & Tech. | 41.679541 |
Isotopes of nitrogen
Nitrogen has two isotopes, N-14 and N-15, both of which are used in various applications. N-15 is used for the production of the radioisotope O-15 which is used in PET. N-15 is also used to study the uptake of Nitrogen in plants and the metabolism of proteins in the human body. N-14 is used for the... | <urn:uuid:83f2da68-6e05-46a4-bb04-8ba0e0e8f7bc> | 3.609375 | 939 | Knowledge Article | Science & Tech. | 58.985376 |
Fire Ant Outcompetes Other SpeciesEven in its
July 2, 2009
Even in its native Argentina, the fire
ant wins in head-to-head competition with other ant species more than
three-quarters of the time, according to Agricultural Research Service (ARS)
ARS scientists at the
American Biological Control Laboratory (SABCL) in Hur... | <urn:uuid:dbdf395a-6b16-4245-a33c-b75c3ae8b2fd> | 3.234375 | 579 | Knowledge Article | Science & Tech. | 32.583712 |
2, 3, 5, 7, 11, 13, 17...
We've known that there are infinitely many primes since c. 300 BC when it was proven by Euclid of Alexandria. Euclid used a very simple and elegant proof by contradiction.
Euclid's proof of the infinitude of primes
First, assume that there are a finite number of primes, p1, p2, p3, ..., pn.
Q ... | <urn:uuid:5ab2fd90-9a0e-44e6-8a12-bbe53de609df> | 3.1875 | 492 | Knowledge Article | Science & Tech. | 78.812674 |
sublimationArticle Free Pass
sublimation, in physics, conversion of a substance from the solid to the vapour state without its becoming liquid. An example is the vaporization of frozen carbon dioxide (dry ice) at ordinary atmospheric pressure and temperature. The phenomenon is the result of vapour pressure and temperat... | <urn:uuid:2a7aff80-4f68-4a6f-ab38-e378532b5eff> | 2.96875 | 119 | Knowledge Article | Science & Tech. | 30.449463 |
2 sound waves in the same direction have average power transmitted in the ratio 1:1
Also ration of their wavelengths lambda1/lambda2 = 1:2
Find ratio of their pressure amplitudes
P1/P2 = A1^2 f1^1 / (A2^2 f2^2)
1 = (A1^2/A2^2) (lambda2^2 / lambda1^2)
So (A1^2/A2^2) = 1/4 or A1/A2 = 0.5
wht is the formula for average po... | <urn:uuid:27df2dec-3ec4-4400-9820-a82a025df894> | 2.875 | 175 | Content Listing | Science & Tech. | 79.168295 |
Dr. Oldfield analyzed the Bosnian pyramids with several cameras and the results proved to be very surprising and unexpected. A number of anomalies were registered, the existence of which could not be attributed to naturally-occurring phenomena.
If one records ordinary hills with this equipment, there are no high-energy... | <urn:uuid:50dc4f23-2d59-42e4-a2fd-439792d355cd> | 2.984375 | 325 | Comment Section | Science & Tech. | 26.272127 |
Some puzzling land formations on Mars's equator could be huge glacier-like deposits of frozen water, new radar observations suggest. The material's radar properties might be explained by unusually porous rocky material instead, but if it is water it would represent a huge amount - as much as a polar ice cap contains, p... | <urn:uuid:64b63eb7-81f5-4dd2-b19d-6894e8807604> | 3.765625 | 1,386 | Comment Section | Science & Tech. | 50.397249 |
DailyDirt: Life Abhors A Vacuum
from the urls-we-dig-up dept
Biologists continue to find signs of life in some of the most remote places on Earth. A variety of organisms seem to be able to thrive under harsh conditions that are similar to extra-terrestrial places elsewhere in our solar system. So finding these extremop... | <urn:uuid:b74a4b81-4b3d-4031-8ffc-2c9b584cfd19> | 2.953125 | 310 | Listicle | Science & Tech. | 42.17 |
Working With Forms in PHP
Working With Forms
Forms are how your users talk to your scripts. To get the most out of PHP, you must master forms. The first thing you need to understand is that although PHP makes it easy to access form data, you must be careful of how you work with the data.
Security Measures: Forms Are No... | <urn:uuid:3e2d27c0-2528-4a93-9012-8cc61c3575bb> | 3 | 491 | Tutorial | Software Dev. | 53.568634 |
This photograph shows many contrails in the sky near Sutherland, NE (November 2004).
Click on image for full size
Courtesy of Susan Gallagher
The white streaks you see coming off airplanes are called contrails. That is short for “condensation trail.” Contrails are actually clouds made by airplanes.
An airplane's exhaus... | <urn:uuid:7612f674-372c-429c-b868-be113f0431b0> | 3.765625 | 538 | Content Listing | Science & Tech. | 64.684612 |
Typical LSCMs take 3-D images of thick tissue samples by visualizing
thin slices within that tissue one layer at a time. Sometimes
scientists supplement these microscopes with spectrographs, which are
devices that measure the pattern of wavelengths, or "colors," in the
light reflected off of a piece of tissue.
This pat... | <urn:uuid:5fc4d2df-c95b-45f3-9dec-801721bc91ab> | 3.421875 | 443 | Truncated | Science & Tech. | 26.702236 |
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2002 October 3
Explanation: A leading candidate for the most mysterious star found in recent times is variable star V838 Monocerotis. At a distance ... | <urn:uuid:a2e78f85-d82d-4c08-b67b-b8d3158ced49> | 3.1875 | 335 | Knowledge Article | Science & Tech. | 40.199671 |
In Stricken Fuel-Cooling Pools, a Danger for the Longer Term
The pools, which sit on the top level of the reactor buildings and keep spent fuel submerged in water, have lost their cooling systems and the Japanese have been unable to take emergency steps because of the multiplying crises.
Experts now fear that the pool ... | <urn:uuid:6b19bdd7-904b-4bdd-9e29-258debf79e86> | 3.125 | 306 | Personal Blog | Science & Tech. | 34.235741 |
This is one of the oldest synchronization primitives in the history of computer science, invented by the early Dutch computer scientist Edsger W. Dijkstra (he used P() and V() instead of acquire() and release()).
A semaphore manages an internal counter which is decremented by each acquire() call and incremented by each... | <urn:uuid:45c63cb9-66ef-4d55-9057-626dddae4ddd> | 4.03125 | 277 | Documentation | Software Dev. | 45.533176 |
Comprehensive DescriptionRead full entry
Description of Pelomyxa palustrisPelomyxa palustris is usually reported as a large multinucleate amoeboid pelobiont, 100-5000 microns long, with small non-motile flagella, endosymbiotic bacteria, refringent cytoplasmic granules (sand and food particles); movement takes place usu... | <urn:uuid:63e5fbab-fff4-4216-827e-a646eaad1bb2> | 2.71875 | 254 | Knowledge Article | Science & Tech. | 20.122252 |
An irrational number is a real number that cannot be expressed in the form , when a and b are integers(b ≠ 0). In decimal form, it never terminates (ends) or repeats.
The first such equation to be studied was 2 = x2. What number times itself equals 2?
is about 1.414, because 1.4142 = 1.999396, which is close to 2. But ... | <urn:uuid:2af38f85-cbb0-4f70-aad1-b06b4a2bfc62> | 3.15625 | 280 | Knowledge Article | Science & Tech. | 65.513235 |
Various astronomical tables, including:
1. A letter from John Senex of London, 16 May 1715, requesting information on a comet and a meeting with Halley. A list of observations and calculations is on the reverse.
2. Table of the different declinations of the stars in the eclipse.
3. Logarithm tables.
4. Annual ephemeris... | <urn:uuid:ac6b508f-97aa-4ede-be4e-aaf5a78e98d0> | 2.828125 | 246 | Content Listing | Science & Tech. | 71.853598 |
Cosmic infrared background (CIB) radiation is expected to arise from the cumulative emissions of pregalactic, protogalactic, and evolved galactic systems. It has long been recognized that measurement of the CIB will provide new insight into energetic processes associated with structure formation and chemical evolution ... | <urn:uuid:db4a89d4-b663-4f3d-9133-c542bdaca96a> | 2.796875 | 467 | Academic Writing | Science & Tech. | 26.166987 |
Two potential signatures of life on Saturn's moon Titan have been found by the Cassini spacecraft But scientists are quick to point out that non-biological chemical reactions could also be behind the observations. Microbes on Titan could eke out an existence by breathing in hydrogen gas and eating the organic molecule ... | <urn:uuid:7134a6f9-afa8-4d35-854e-a14cef66c9b8> | 3.3125 | 224 | Truncated | Science & Tech. | 29.151326 |
Getting started with CLP(R)
The first thing to know about CLP(R) is that it
is a declarative programming language, rather than one
of the imperative languages like C++ or Java to which
you are used. This affects the way in which you program in tow ways.
- In general your program specifies the solution you are looking f... | <urn:uuid:25fc83d1-f2b5-45f2-a305-9462d50b94dc> | 3.609375 | 1,091 | Tutorial | Software Dev. | 82.668173 |
Did you know the jawless fish are known to be the earliest known vertebrates? Researchers have identified jawless fish to be very ancient like five hundred million years old. Jawless fish are of the group Agatha. Most of the jawless fish class is extinct. Two classes of jawless fish that are still living are the hagfis... | <urn:uuid:d03e30e7-2bc4-4532-8ada-dfa8d4a369bc> | 3.796875 | 638 | Knowledge Article | Science & Tech. | 63.519416 |
Curious About Life: Interview with Felipe Gómez
Provided by the Spanish government, the Rover Environmental Monitoring System (REMS) will monitor the daily weather on Mars to help determine habitability at the planet's surface. Felipe Gómez, of the Centro de Astrobiologia in Spain, is one of the scientists working with... | <urn:uuid:2a725bcc-28fb-4adf-969b-1038eef55e93> | 3.171875 | 936 | Audio Transcript | Science & Tech. | 36.924651 |
Bats are the only mammals that truly fly, rather than just gliding. The bats are very numerous, there being well over 900 recognised species. They are divided into two types - the megabats, which mainly eat fruit, and the microbats, which mainly eat insects.
Scientific name: Chiroptera
The shading illustrates the diver... | <urn:uuid:b4d6cbf8-c5cd-4418-88ab-12d959e2c620> | 3.890625 | 671 | Knowledge Article | Science & Tech. | 62.998488 |
Real-time polymerase chain reaction, also called quantitative real time polymerase chain reaction (qPCR) or kinetic polymerase chain reaction, is a laboratory technique based on polymerase chain reaction, which is used to amplify and simultaneously quantify a targeted DNA molecule. It enables both detection and quantif... | <urn:uuid:f9bce8b3-9068-4a38-9b19-bce7258a9dae> | 3.546875 | 1,151 | Knowledge Article | Science & Tech. | 21.411281 |
When James Watson and Francis Crick elucidated the structure of DNA in 1953, they solved one mystery, but created another.
For almost a hundred years after the publication of On the Origin of Species by Charles Darwin in 1859, the science of biology rested secure in the knowledge that it had explained one of humankind’... | <urn:uuid:0af2eee8-4bf6-488c-9e5a-e189d9a90f82> | 3.65625 | 1,415 | Nonfiction Writing | Science & Tech. | 27.582743 |
Pitch vs Frequency
Pitch and frequency are two concepts discussed in physics and music. Frequency is the number of repetitive occurrences per unit time whereas pitch is an intuitive concept associated with the frequency of a sound wave. These concepts are widely used in fields such as acoustics, music, waves and vibrat... | <urn:uuid:268bf356-d5b1-41bd-8c79-9f92a6c10925> | 3.96875 | 587 | Knowledge Article | Science & Tech. | 38.0325 |
Okay, we are about to go into the details of SQL queries, but before that we should say one
last thing about SQL database structures. Specifically,
most databases store their data in terms of data types.
Defining data types allows the database to be more
efficient and helps to protect you against adding bad
data to you... | <urn:uuid:6d1c5399-a214-4b9c-a785-96da131599ed> | 3.765625 | 310 | Tutorial | Software Dev. | 44.80532 |
int dup(int fildes);
int dup2(int fildes, int fildes2);
The dup() and dup2() functions provide an alternative interface to the service provided by fcntl() using the F_DUPFD command. The call:
fid = dup(fildes);
shall be equivalent to:
fid = fcntl(fildes, F_DUPFD, 0);
fid = dup2(fildes, fildes2);
shall be equivalent to:... | <urn:uuid:3e7a5a6a-ad84-45eb-8a8c-774946b71ef3> | 2.78125 | 649 | Documentation | Software Dev. | 58.176302 |
Current information on algal blooms
Algal Bloom Monitoring August 30, 2012: Cyanobacterial amounts are low at sea, no changes in lake observations
Amounts of cyanobacteria are quite low at the Finnish sea areas. Low amounts of cyanobacteria have been observed in the Gulf of Finland, in the Archipelago Sea, and the Both... | <urn:uuid:816307f7-3762-47c4-af43-a9fc399bfeb3> | 3.140625 | 474 | Knowledge Article | Science & Tech. | 27.448684 |
Researchers at the CNRS-AIST Joint Robotics Laboratory (a collaboration between France's Centre National de la Recherche Scientifique and Japan's National Institute of Advanced Industrial Science and Technology) are developing software that allows a person to drive a robot with their thoughts alone. The technology coul... | <urn:uuid:8cf11888-b0f2-478d-bfd9-5827269fac25> | 3.359375 | 511 | Comment Section | Science & Tech. | 35.23472 |
Global Warming Kills Whitebark Pines, Threatening Mountain Ecosystems
Millions of dying whitebark pine trees could be disastrous for the delicate ecosystem that supports grizzlies, birds and Western water supplies.
Across the American West, whitebark pine, a linchpin of high-altitude ecosystems, is rapidly falling vict... | <urn:uuid:e534f6be-373a-4fc2-afb8-53e3aed5bd1b> | 3.671875 | 1,290 | Knowledge Article | Science & Tech. | 31.516085 |
"Each bee on her return is followed by three or four companions . . . how they do it has not yet been observed" Aristotle, Historia Animalium, IX
"In the summer of 1944 a few very simple experiments led to a result that was just as unexpected as it was thrilling" Karl von Frisch on the discovery of the dance language o... | <urn:uuid:794cb955-9b79-4038-9ef5-55a161b78182> | 4.15625 | 1,517 | Knowledge Article | Science & Tech. | 47.35749 |
"This provides the accuracy missing in previous calculations,
and it makes bigger systems possible."
Sometimes proteins are like the Wicked Witch. Add water, wait a nanosecond and you can almost hear that piteous whimper. "I'm mel-l-l-ting!" Well, not really. But there may be an audible groan from biochemists as they o... | <urn:uuid:f060c399-48e7-4ec2-ae93-1dc33dc8c607> | 3.328125 | 960 | Academic Writing | Science & Tech. | 21.159698 |
I'm sorry for pause in writing new posts about design patterns.
So, today I'm going to write a post about the most popular and well-known design pattern - Singleton.
The essence of Singleton is to provide :
- exactly one instance of class across the system;
- simple access to it.
The implementation of Singleton based o... | <urn:uuid:8c279192-41c1-455e-8032-4592ee4ed39f> | 2.796875 | 479 | Personal Blog | Software Dev. | 50.366905 |
To answer big questions, scientists need to think big about their observing tools.
May 22, 2006
|Over the next decade, scientists will make observations to learn more about cosmology's biggest mystery: the nature of dark energy. A slew of telescopes are in the planning or construction stages to aid in this effort.|
You... | <urn:uuid:8cca4f0c-be05-48df-8526-03e3a9922963> | 2.9375 | 229 | Truncated | Science & Tech. | 43.083846 |
On Tuesday night, I headed down to the beautiful Bell House in the Gowanus section of Brooklyn for the latest Secret Science Club lecture, featuring astrophysicist Dr Jeremiah Ostriker, professor emeritus of Princeton University, currently of Columbia University. Dr Ostriker has enjoyed a long, storied career in astrop... | <urn:uuid:b99985f3-479a-46f8-92f3-288e605f8519> | 2.84375 | 1,560 | Personal Blog | Science & Tech. | 37.15652 |
Subcutaneous rock forms
Tadej Slabe - (28/2,1999)
Subcutaneous rock forms occur on karst surfaces covered with sediment or soil. They are the consequence of water running along the contact between rock and soil, the percolation of water through the soil, and inflow of water to the surface of the soil surrounding the ro... | <urn:uuid:82dd7fb2-b330-4c81-9154-56d2b91fbe50> | 3.046875 | 120 | Truncated | Science & Tech. | 40.405523 |
Marcellin Pierre Eugène Berthelot:
Marcellin Berthelot was a French chemist.
October 27, 1827 in Paris, France
March 18, 1907 in Paris, France
Claim to Fame:
Berthelot was a French chemist who believed all chemical reactions depended on the action of physical forces that could be measured. He was also partly responsibl... | <urn:uuid:06115a62-d4ea-4f19-8f78-d962e204a231> | 3.46875 | 193 | Knowledge Article | Science & Tech. | 34.859286 |
Sub-annually resolved ice core chemistry data from various sites on the Antarctic Ice Sheet were obtained from 1999 to 2008 during the US International Trans-Antarctic Scientific Expedition (US ITASE) deployments. Researchers conducted experiments approximately every 100-300 km looking for clues representing climatic c... | <urn:uuid:d6d840a9-705d-4019-8555-b5a6e5bcc3a2> | 3.234375 | 251 | Academic Writing | Science & Tech. | 28.879493 |
Let us consider another strategy to deal with our diameter problem. Let us try to associate other graphs to our family of sets.
Recall that we consider a family of subsets of size of the set .
Let us now associate more general graphs to as follows: For an integer define as follows: The vertices of are simply the sets i... | <urn:uuid:2926ac7d-04c0-46f0-854f-3f06f5bc4ebf> | 2.84375 | 214 | Academic Writing | Science & Tech. | 59.159176 |
A small meteorite named ALH84001 that was found in the mid 1980's in Antarctica was analyzed carefully years later; surprisingly chemical tests indicated evidence for possible past life on Mars. With such an announcement pending, the researchers had all they could do to prevent a gushing leak of the sensational news.
T... | <urn:uuid:5106c147-e663-4da9-89b8-e4577d78a430> | 3.5 | 429 | Knowledge Article | Science & Tech. | 52.933661 |
You can add these boxes to your site.
Every thing has a link like this:
Add this to your blog
Just click on it and follow the one-step instructions. Whenever you add one of these boxes to your site you will be getting links back to you in our site!
In radio astronomy, the flux unit or jansky (symbol Jy) is a non-SI uni... | <urn:uuid:29ebe4a2-14de-4a09-b211-77f608d2f418> | 2.703125 | 210 | Truncated | Science & Tech. | 52.620664 |
If a multimeter has a resistance (1M ohm, say) when measuring voltages how do I take that into account in my error?
By treating the multimeter as a resistor in parallel with the rest of the circuit, connected at the contact points. When you measure the potential difference across those points, you can compute the poten... | <urn:uuid:42f0b2a0-eac9-4a42-97a3-23bcb79ba47f> | 2.6875 | 225 | Q&A Forum | Science & Tech. | 30.26587 |
The monitor executes one thread at a time. Assuming you have T1-T10 threads, 9 are
BLOCKED and one is
RUNNABLE. Every once in a while, the monitor picks a new thread to run. When that happens, the chosen/current thread, say T1, goes from
BLOCKED. Then another thread, say, T2, goes from
RUNNABLE, becoming the current th... | <urn:uuid:dae8c0ca-fbee-4f5f-86cd-bb3827347926> | 2.6875 | 248 | Q&A Forum | Software Dev. | 65.24393 |
Now, these ideas have an obvious role to play in physics, but it's the same role they play in any science which uses parameter estimation. Knowing something about the limits of statistical inference is often useful --- constant readers may recall that the Fisher information matrix plays a leading role in Optimum Experi... | <urn:uuid:de38ff4f-58a5-420b-bb15-dce2cdf881a2> | 2.859375 | 1,971 | Nonfiction Writing | Science & Tech. | 35.300605 |
In my new book, The Great Global Warming Blunder: How Mother Nature Fooled the World’s Top Climate Scientists, I show the results of experiments with a simple climate model that runs in an Excel spreadsheet. The model is meant to illustrate how natural monthly-to-yearly variability in global (a) cloud cover and (b) sur... | <urn:uuid:1bd7cf23-8091-4ca4-9d11-f290315d38dc> | 3.046875 | 622 | Personal Blog | Science & Tech. | 37.164026 |
In this lesson, we will see some examples on the
perimeter of a parallelogram...
About This Lesson
In this lesson, we will:
See an example on finding the perimeter of a parallelogram.
See another example on finding the
side length of a parallelogram.
The study tips and math video
below will explain more.
A parallelogra... | <urn:uuid:b93a791a-65ae-48f5-b399-8eaa8e40a3d2> | 4.15625 | 268 | Tutorial | Science & Tech. | 52.041887 |
10.23.12 - The sun emitted a significant solar flare on Oct. 22, 2012, peaking at 11:17 p.m. EDT.
10.22.12 - Newly named sunspot AR1598 has release an M5 class solar flare. This is the same region that released an M9 flare on Oct. 20, 2012.
10.20.12 - The sun emitted a significant solar flare, an M9, peaking at 2:14 p.... | <urn:uuid:734e9dc9-1a3d-430f-bfc2-8082af9435f3> | 3.265625 | 725 | Content Listing | Science & Tech. | 98.090034 |
Special cells having a hollow central cathode were immersed in liquid air for an extended period to insure that any gases, if present, were condensed on the outer alkali metal coated walls. The temperature of the cathode was controlled by a stream of evaporating liquid air, whereby all temperatures between +20 and - 18... | <urn:uuid:40e5f193-b7b9-4b37-899d-db78cda5627f> | 2.90625 | 368 | Academic Writing | Science & Tech. | 38.579919 |
Top Speed: 107,000 mph
In 2003, the Galileo mission to study Jupiter and its moons had already been extended several years and the space probe was running out of propellant. Probes to distant planets use nuclear thermal generators, which keep them operational for decades, but eventually wear out, says Roger Launius, an... | <urn:uuid:9cc0a7c0-577a-4315-8d8a-cfe159381201> | 3.46875 | 202 | Listicle | Science & Tech. | 65.479091 |
How the MBDI Compares
Funder & Affiliates
Rank of drought severity
To compare drought severity for a specified time frame, the Moisture Balance Drought Index (MBDI) uses a ranking system based on where that time frame falls in the historical line-up since 1895.
The driest years will fall into the lowest ranks, such as ... | <urn:uuid:aae167ab-fa1e-4574-a7d7-c955a8231b4b> | 3.0625 | 351 | Knowledge Article | Science & Tech. | 49.513669 |
25. The main reason why certain lipids will preferentially form micelles rather than bilayers is that a. they are amphipathic. b. the diameter of their polar head groups is larger than that of their hydrophobic tails. c. their tails are longer than their heads. d. they are less soluble in an aqueous environment than li... | <urn:uuid:8c0841e7-16fb-423a-8628-2d0a8e98023a> | 3.046875 | 83 | Q&A Forum | Science & Tech. | 73.99806 |
...This is a project to be proud of at so many levels. It will attract tourists. It will set a positive precedent, nationally and globally, on environmental policy and action.
-- Joy Lapseritis, Falmouth resident & marine biologist
See all stories in this topic...
Two new important studies on climate change
Monday, Jan... | <urn:uuid:79ed5616-f198-4f89-8d1b-6692c8413f4a> | 2.9375 | 1,480 | Content Listing | Science & Tech. | 43.895507 |
As oceans absorb carbon dioxide, they become more acidic, diminishing the amount of available carbonate. Because carbonates are the building blocks that reefs and other marine species need to grow and maintain shells and body structures, ocean acidification poses a grave threat to these species.
Though often miniscule ... | <urn:uuid:307cf3f8-d8c4-47d8-8047-44dcb64ebf23> | 3.796875 | 297 | Knowledge Article | Science & Tech. | 24.524244 |
If you enjoy gardening, you know how much it can cost to keep your plants alive. You also know how frustrating it is when an unexpected frost destroys them.
Honeybees make propolis by collecting the secretions of trees and other plants where they live; thus the make-up of propolis varies depending on the plant life aro... | <urn:uuid:bf3af3c5-c0e1-4b8e-a692-6767a5c92c15> | 3.09375 | 167 | Content Listing | Science & Tech. | 52.442839 |
1. Find the volume of the solid formed by rotating the region enclosed by
x=0, x=1, y=0, y=7+x^5 about the x-axis.
2. Find the volume formed by rotating the region enclosed by:
x=4y and y3=x with y0 about the y-axis.
3. The region between the graphs of y=x2 and y=4x is rotated around the line y=16.
The volume of the re... | <urn:uuid:d717dd9a-ee38-4189-aa6d-e8b2162633ec> | 3.484375 | 109 | Tutorial | Science & Tech. | 92.680965 |
Consider the equation 1/a + 1/b + 1/c = 1 where a, b and c are
natural numbers and 0 < a < b < c. Prove that there is
only one set of values which satisfy this equation.
Powers of numbers behave in surprising ways. Take a look at some of
these and try to explain why they are true.
I start with a red, a blue, a green an... | <urn:uuid:9f202c56-0395-4c44-8e26-c226df65bfb1> | 3.6875 | 1,809 | Content Listing | Science & Tech. | 77.676458 |
A podcast is a an audio file published on the web. The files are usually downloaded onto computers or portable listening devices such as iPods or other players.
Read more about podcasting from webcontent.gov
HOST: Welcome to Diving Deeper where we interview National Ocean Service scientists on the ocean topics and info... | <urn:uuid:998bbf20-6164-4d91-a77c-09994cabd4cb> | 3.921875 | 3,466 | Audio Transcript | Science & Tech. | 53.754347 |
An interesting way to generate electricity from the sun w/o solar panels. Since a car heats up when the windows are up even on a cloudy day, due to the same greenhouse effect of glass, this should be able to use energy from the sun even on cloudy days.
The solar updraft tower is a renewable-energy power plant. It combi... | <urn:uuid:68518f56-f1c8-4bc5-9313-d5b06ef7d6b6> | 3.546875 | 179 | Personal Blog | Science & Tech. | 41.999596 |
“Big red” is the nickname that MBARI marine biologists gave to this startlingly large jellyfish, which grows over 1 m (3 ft) in diameter. After determining that it was an entirely new species of jelly, they named itTiburonia granrojo after MBARI’s remotely operated vehicle Tiburon.
This giant scyphomedusa would be hard... | <urn:uuid:88ea2cd3-438a-480a-b033-42e7208accb7> | 3 | 163 | Knowledge Article | Science & Tech. | 52.129628 |
Combined Release and Radiation Effects Satellite
Launch Date: July 25, 1990
Mission Project Home Page - http://nssdc.gsfc.nasa.gov/nmc/masterCatalog.do?sc=1990-065A
The Combined Release and Radiation Effects Satellite (CRRES) was launched into a geosynchronous transfer orbit (GTO) for a nominal three-year mission to in... | <urn:uuid:b2172df7-cb95-4cb1-bba6-24576e459682> | 3.40625 | 489 | Knowledge Article | Science & Tech. | 41.607203 |
A comparison of metallographic cooling rate methods used in meteorites
The primary objective of this study was to test the postulate that cooling rates acquired from metal grains in chondrites are consistent with those from iron meteorites. Both types of metal occur in some Group IAB meteorites, which are mixtures of m... | <urn:uuid:f112932c-d422-432e-86f5-139b89e875ad> | 3.21875 | 502 | Academic Writing | Science & Tech. | 26.849371 |
Johannes Kepler lived from 1571 to 1630. Kepler was a German astronomer who worked closely with Galileo and Tycho Brahe. Kepler came up with the three laws of planetary motion, which he is most famous for. Kepler calculated some of the most well known mathematical calculations to this day as well as gave the first proo... | <urn:uuid:898a252d-5e46-408c-8712-39bca5fd6177> | 3.484375 | 1,129 | Knowledge Article | Science & Tech. | 59.144942 |
Visual binaries are systems in which the individual stars can be seen through a telescope.
Spectroscopic binaries are systems in which the stars are so close together that they appear as a single star even in a telescope. The binary nature of the system is deduced from the periodic doppler shifts of the wavelengths of ... | <urn:uuid:44296c15-e885-4154-9737-e5e8ca951fdf> | 4.09375 | 389 | Knowledge Article | Science & Tech. | 48.138989 |
Neutron Stars Join The Black Hole Jet Set
This artist's illustration depicts the jet of relativistic particles blasting out of Circinus X-1, a system where a neutron star is in orbit with a star several times the mass of the Sun. The neutron star, an extremely dense remnant of an exploded star consisting of tightly pac... | <urn:uuid:37d9e15b-927f-4db5-83c8-4dc16f8ba8e8> | 3.96875 | 490 | Knowledge Article | Science & Tech. | 48.298994 |
When we visualize software as a machine, it becomes clear just how unwise it is to invent too much in a new software system. Picture the overall software as a factory assembly line of robots, or a new kind of automobile. The major software modules are sections of the factory, or important pieces of the automobile. The ... | <urn:uuid:0f9aef31-f1b3-49ba-9619-6493b8e9d070> | 3.578125 | 1,483 | Personal Blog | Software Dev. | 42.43252 |
First the good news: North America's monarch butterfly (Danaus plexippus) has bounced back after its worst year ever. Now the bad: it is still the fourth worst year since records began in 1993.
WWF Mexico's latest survey of the butterfly's Mexican heartland shows that the insects wintering there since November colonise... | <urn:uuid:b4fc6861-704d-4a28-acbe-315405c47029> | 3.390625 | 318 | Truncated | Science & Tech. | 42.372965 |
The fictional world of Arthur C. Clarke's 2001: A Space Odyssey this week came a step closer to reality. NASA has begun testing a computer system designed 'to look over the astronaut's shoulder' and give advice on malfunctions and faults that occur during space shuttle flights.
A prototype of the system, which uses adv... | <urn:uuid:02a6e037-1b51-4ad6-8f8f-bae560f9077b> | 3.328125 | 209 | Truncated | Science & Tech. | 39.752917 |
Write a program that makes use of a class called Employee that will calculate an employee's weekly paycheque. Design your class based on the UML diagram to the right as well as the following notes:
A static field, empCount, keeps track of the number of instantiated employees and can be retrieved using the static method... | <urn:uuid:838e400d-3f34-48a6-991d-2c580949aec5> | 2.9375 | 441 | Tutorial | Software Dev. | 54.073409 |
My next dive into attempting to write a program deals with a Fibonacci-se-quence. I have started an outline to portray the ideas of how I think the flow of code should go to produce this program and have come across some questions.
I want my program to query the user for four separate integers. The first two are the be... | <urn:uuid:7687a6d5-f388-44ec-a906-75bbb44b8b74> | 2.796875 | 264 | Q&A Forum | Software Dev. | 60.033552 |
Scheme provides a very powerful control abstraction named call-with-current-continuation. Not only is the name intimidating, but many introductions to its semantics are as well. This introduction tries to be much gentler. C programmers can also read call-with-current-continuation-for-C-programmers.
To understand this t... | <urn:uuid:591e36f5-1578-4ea8-97ef-0ce3f450dbc3> | 3.046875 | 2,266 | Documentation | Software Dev. | 58.802681 |
The Database Environment
This chapter describes the database environment which is composed of a set of Mimer SQL system databanks, one or more idents authorized to connect to the database and the databanks created by the idents. It also describes database security and data integrity.
The objects which are created in th... | <urn:uuid:4426e582-ba6b-41bc-8d71-f6d1d3eb3353> | 2.859375 | 123 | Documentation | Software Dev. | 26.127576 |
How We Present
1,000-year-old farming secrets could save the Amazon rainforest
by Alasdair Wilkins
io9.com Translate This Article
9 April 2012
On 9 April 2012 io9.com reported:
An international team of archaeologists have made an intriguing discovery -- the peoples who farmed the Amazon long before the arrival of Europ... | <urn:uuid:7b9e2058-8cd2-431e-8b36-658b99b65c72> | 3.078125 | 281 | Truncated | Science & Tech. | 32.181145 |
A charged particle moves along a line joining two charged particles which are fixed at the locations and . Assume the interactions between the moving charged particle and each of the fixed charges is repulsive and obeys an inverse square law. The differential equation
for some constants and models the motion of the tra... | <urn:uuid:85c60f0b-8b4f-4dde-af48-32cdfdc3ca53> | 2.96875 | 217 | Q&A Forum | Science & Tech. | 49.127111 |
Boosted carbon emissions from Amazon deforestation
Article first published online: 21 JUL 2009
Copyright 2009 by the American Geophysical Union.
Geophysical Research Letters
Volume 36, Issue 14, July 2009
How to Cite
2009), Boosted carbon emissions from Amazon deforestation, Geophys. Res. Lett., 36, L14810, doi:10.1029... | <urn:uuid:28728834-c196-4e48-aadc-e00d6ad9c14b> | 2.796875 | 346 | Academic Writing | Science & Tech. | 41.023294 |
Aug 19, 2009, 5:13 AM
Post #1 of 4
Hi! I'm trying to understand a perl script. There are some switches (I guess) used, and I can't seem to find their role/use.
-e and -s switches?
The code looks like:
my $filename ="doc";
my $filename1 = -s $filename;
while( -e $filename && $filename1 == -s $filename )
What is the role... | <urn:uuid:d6d7606b-4874-48b5-8254-4f0e8d2ec052> | 2.765625 | 113 | Comment Section | Software Dev. | 82.117582 |
No one know how will a quantum Internet work as it is still in its infancy of the idea. The main difficulty is that quantum information are tight to a particular physical system. In classical communication, you can copy any signal, store and retransmit later easily. However, in quantum communication, once you have done... | <urn:uuid:627454d6-3212-4ec4-b6e2-7c2dc813f306> | 3.46875 | 466 | Q&A Forum | Science & Tech. | 39.839429 |
“Everything about it would be bad,” says Mark Hammergren, an astronomer at Adler Planetarium in Chicago, starting with the sad attempt to scoop some of that star candy up. Even though white dwarfs are fairly common throughout the universe, the nearest one is still 8.6 light-years away, which is roughly 81,360,544,300 k... | <urn:uuid:158e2f31-da79-461e-aa94-281817583577> | 2.765625 | 518 | Personal Blog | Science & Tech. | 62.820647 |
How to yell across a solar system
The transceiver in the movie sends the data through space using electromagnetic energy. One kind of electromagnetic energy is the light we see with our eyes. But there are many other forms of electromagnetic energy. One form is radio waves. We can't see radio waves, but we know how to ... | <urn:uuid:f2e27387-ceaf-4639-b1c6-b2b0b42d6e1e> | 3.296875 | 171 | Knowledge Article | Science & Tech. | 54.55227 |
The Latin name of all the major insect orders ends in “ptera”, which means “wing”, and for good reason! The majority of the thirty or so orders of insects are flighted arthropods*, and their wings help to define them both ecologically and taxonomically. It is even suggestive as to the course of their evolution!
For exa... | <urn:uuid:5ef58d38-8a50-4eb6-b536-e83d7bbc3836> | 4.03125 | 957 | Personal Blog | Science & Tech. | 42.405016 |
Introduction: XAML in WEB
A rich Internet application (RIA) is an entirely new kind of web experience that is engaging, interactive, lightweight, and flexible. RIAs offer the flexibility and ease of use of an intelligent desktop application, and add the broad reach of traditional web applications. This richer functiona... | <urn:uuid:72bdcb49-5966-41a1-9c12-4d443abb2b7d> | 3 | 2,897 | Knowledge Article | Software Dev. | 34.211937 |
programs from prekindergarten through grade 12 should enable all students
When students can see the connections across
different mathematical content areas, they develop a view of mathematics
as an integrated whole. As they build on their previous mathematical understandings
while learning new concepts, students become... | <urn:uuid:339148d1-27cd-42b9-9ed4-a3d577200b99> | 3.96875 | 2,380 | Tutorial | Science & Tech. | 49.405815 |
|Back to AutoLisp Home
The Ultimate AutoLisp Tutorial
What is a "car of a cdr"?
Beginner - You know how to spell AutoLisp and that is about it. From opening notepad, writing your first program, saving your first program, to executing your first program and checking the variables inside AutoCAD. I will cover it all. Ste... | <urn:uuid:3e9383e1-a433-4f0c-9bce-af5bad5bccf9> | 3.265625 | 198 | Tutorial | Software Dev. | 60.160763 |
In 1995-1996, John Goold was gathering data on the daily activity patterns of Odonata. He made collections at various times of the day and in different weather conditions to help determine under what condition dragonflies fly. Johnalso used data collected by Dirk Westfall and Chris Todd. John found strong correlations ... | <urn:uuid:9c593ec2-9972-4914-a18c-15ab0a8e51b9> | 2.859375 | 143 | Knowledge Article | Science & Tech. | 27.610455 |
You know there are no such things as cross-browser layers, because the
layer object only exists in a Netscape Navigator version 4 or later
browser. However, Internet Explorer is rich enough to present something
of its own that resembles layers. This article discusses problems with
writing code for layers in both browse... | <urn:uuid:0941f129-267a-4da1-a238-19fbdc603d6a> | 2.78125 | 1,200 | Tutorial | Software Dev. | 52.320821 |
This is a somewhat outdated term used to refer to a sub-interval of the Holocene period from 5000-7000 years ago during which it was once thought that the earth was warmer than today. We now know that conditions at this time were probably warmer than today, but only in summer and only in the extratropics of the Norther... | <urn:uuid:0a09f47a-4d63-481b-98e9-374f03c5899b> | 3.84375 | 363 | Knowledge Article | Science & Tech. | 59.30454 |
Planck’s cooling system composite
May 26, 2009
In order to achieve its scientific objectives, Planck's detectors have to operate at very low and stable temperatures. The spacecraft is therefore equipped with the means of cooling the detectors to levels close to absolute zero (-273.15º C), ranging from about -253 º ... | <urn:uuid:a2ec4977-1308-4c7c-99d7-aa4584d1f984> | 3.03125 | 114 | Truncated | Science & Tech. | 20.544641 |