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does the resistance double as you double the length of a
piece of wire?
Is this a trick question? Seems like it might be... Yes, the resistance is
proportional to the length. Therefore if the length is doubled, the
resistance is doubled. Interestingly, the relationship of resistance to
diameter is not so simple and the... | <urn:uuid:99e5286e-ac86-4c04-97ae-b595ef6e0f42> | 3.671875 | 310 | Q&A Forum | Science & Tech. | 45.630987 |
Adaptive optics is a technology that can remove the blurring effects of turbulence in the earth’s atmosphere, so that telescopes on the ground can “see” as clearly as if they were in space. I will describe the basic principles of adaptive optics, and illustrate why lasers are needed to increase the fraction of the sky ... | <urn:uuid:b75f1951-9702-4dd2-be9a-0ec2c8d818b8> | 3.640625 | 125 | Academic Writing | Science & Tech. | 25.694358 |
Twisting Space & Time
Credit: Joe Bergeron of Sky & Telescope magazine
An artist's impression of space and time
twisting around a spinning black hole.
Astronomers might have already observed the effects of gravitomagnetism. Some black holes and neutron stars shoot bright jets of matter into space at nearly light speed.... | <urn:uuid:e8ad1fe0-cbb4-4ab4-967f-dbb6e27b9ef2> | 3.546875 | 395 | Personal Blog | Science & Tech. | 41.906593 |
A very useful concept in our study of root systems will be that of a Weyl chamber. As we showed at the beginning of last time, the hyperplanes for cannot fill up all of . What’s left over they chop into a bunch of connected components, which we call Weyl chambers. Thus every regular vector belongs to exactly one of the... | <urn:uuid:7d9579d1-6289-47a7-aa8f-68973aa6811b> | 3.078125 | 362 | Personal Blog | Science & Tech. | 55.870263 |
Science subject and location tags
Articles, documents and multimedia from ABC Science
Wednesday, 15 May 2013
StarStuff Podcast Record-setting gamma-ray burst shocks astronomers. Also; study suggests water on Earth and Moon came from the same source, and Earth's inner-core out of sync with the rest of the planet.
Wednes... | <urn:uuid:caa86dc3-fdb7-4d4a-8405-79287e17850d> | 2.828125 | 775 | Content Listing | Science & Tech. | 47.848608 |
In order to deliver production-ready code at the end of every iteration, the iterative quality assurance approach relies on robust definitions of acceptance criteria for each story card and automated testing to unearth and fix bugs early in the process.
Each story card should describe both unit tests and the specific p... | <urn:uuid:250fe88e-c7f5-4e6e-9066-9eaddd047c51> | 2.765625 | 307 | Documentation | Software Dev. | 35.114457 |
Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °
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Scientific notation, also known as standard form or in exponential notation, is a way of writing numbers, which can contain values for large or ... | <urn:uuid:3247de02-35c4-4f8d-9e5e-f585505a16d6> | 3.46875 | 350 | Comment Section | Science & Tech. | 70.200628 |
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A Science Strategy for the Exploration of Europa
drainage channels within the glacier. The glacier itself may be several... | <urn:uuid:1f307a1b-cd30-4147-a4e4-694d26605637> | 3.890625 | 990 | Knowledge Article | Science & Tech. | 35.36877 |
Three years ago, Pinon Middle School science teacher Rochelle Silvers asked her seventh-grade students if anyone would like to do a science project for the state science fair. The only student to raise his hand was Garrett Yazzie.
Garrett, a Navajo Indian, volunteered because no one else did, and because he was excited... | <urn:uuid:5463ef32-782e-4f68-91a0-bd5b6abf1351> | 3.390625 | 1,181 | Nonfiction Writing | Science & Tech. | 49.041068 |
The failure of ghostly subatomic messengers called neutrinos to show up at an Antarctic telescope has knocked down a major astrophysical theory involving some of the most dramatic explosions in the universe.
"I would have preferred to have seen neutrinos," says the IceCube telescope's principal investigator Francis Hal... | <urn:uuid:55950682-dcac-4528-9030-a94b13ad5b7a> | 3.625 | 1,155 | Comment Section | Science & Tech. | 49.751696 |
JSON is a simple language for representing data on the Web. Linked Data is a technique for creating a graph of interlinked data across different documents or Web sites. In Linked Data, “things” are identified using IRIs, which are typically dereferencable and thus may be used to find more information about a particular... | <urn:uuid:a1fcc101-c21a-4978-8ee2-a6d5d9cd63c8> | 3.015625 | 237 | Knowledge Article | Software Dev. | 36.244064 |
We constantly hear that the warmest years on record have all occurred in the most recent decades, and of course, we are led to believe this must be a result of the ongoing buildup of greenhouse gases. In most places, we have approximately 100 years of reliable temperature records, and we wonder if the warmth of the mos... | <urn:uuid:415235c7-95da-4917-ac74-eb14d3bd8d18> | 3.375 | 1,400 | Knowledge Article | Science & Tech. | 49.179624 |
The picture to the right is an aerial photograph of Fermi National Accelerator Laboratory illustrating the heterogeneous landscape. Seven different habitats were sampled for two years to compare prey availability across the landscape. A log-linear analysis was then used to relate spatio-temporal changes in prey to the ... | <urn:uuid:3756f025-03db-46c3-b1f1-16104e9fdf9c> | 3.671875 | 1,279 | Academic Writing | Science & Tech. | 25.026287 |
Microtubules are a structure in the cytoskeleton, they are rope like polymers that grow to a length of about 25 micrometers (25000 nm), and have an outer-diameter of around 25 nm. For comparison, the mean spacing between atoms is on the order of 0.1 to 0.2 nm; so the micro tubule really is micro: about 200 atoms across... | <urn:uuid:fa12721a-e508-4aa8-a132-20839baf5f55> | 3.1875 | 721 | Q&A Forum | Science & Tech. | 43.721676 |
We are here one more time for another edition of our 3081: Program Design and Development writing assignment, this time getting into the topic called: Testing.
Testing? ...what do I mean by testing in terms of computer science? Well, testing is all about producing failures in our own code just to be sure that it is doi... | <urn:uuid:8124ba0b-2721-4f55-9fcd-b1c269fbe84b> | 3.65625 | 561 | Personal Blog | Software Dev. | 54.170796 |
Control is what attracts many OS developers to assembly, often is what leads to or stems from assembly hacking. Note that any system that allows self-development could be qualified an "OS", though it can run "on the top" of an underlying system (much like Linux over Mach or OpenGenera over Unix).
Hence, for easier debu... | <urn:uuid:a647ecaa-8fe3-4ecf-bb8e-3a704643b16c> | 2.703125 | 246 | Tutorial | Software Dev. | 52.590591 |
NERVA is an acronym for Nuclear Engine for Rocket Vehicle Application, a joint program of the U.S. Atomic Energy Commission and NASA managed by the Space Nuclear Propulsion Office (SNPO) until both the program and the office ended at the end of 1972.
NERVA demonstrated that nuclear thermal rocket engines were a feasibl... | <urn:uuid:27b6749d-0c7d-4066-8f69-b9da366aa71f> | 3.796875 | 2,900 | Knowledge Article | Science & Tech. | 42.774612 |
Earth Shadow on Moon
June 07, 2003
The above image shows the Earth's shadow covering a portion of the Moon. The photo was taken over Quebec, Canada during a total lunar eclipse on January 20, 2000. As was mentioned in the caption of yesterday's Earth Science Picture of the Day, the position of the umbra (deepest part o... | <urn:uuid:470344fb-e60a-4c19-9516-53db3ed0a838> | 3.921875 | 175 | Personal Blog | Science & Tech. | 55.407597 |
I know what sonic.blade means, though I'm not sure how well I'll go with explaining it - I haven't done maths of any real sort in years, and multi-dimensional stuff in even longer.
If we first of all think about a unit sphere. The sphere exists for values of x, y, and z between -1 and 1, and does not exist for all othe... | <urn:uuid:a035ee28-fcca-4a8f-9e2b-ca95dde1d9c4> | 2.890625 | 729 | Comment Section | Science & Tech. | 74.785468 |
|"Even if such relatively simple molecules, such amino acids (the building blocks of proteins), could populate the hypothetical primitive oceans, the formation of biologically active proteins could never occur. Under these conditions, the sequence of the amino acids would be purely by chance. There we 20 different amin... | <urn:uuid:cd5a6eff-5982-45b7-b028-357892a1a9c3> | 3.640625 | 2,021 | Comment Section | Science & Tech. | 43.33008 |
Plants in Moonlight
Can photosynthesis happen in a bright full moon?
No, according to the following site, moonlight is not strong enough for
" *moonlight is 1/50,000 the intensity of sunlight"
"*moonlight is too weak to support photosynthesis"
Anthony Brach Ph.D.
Click here to return to the Botany Archives
Update: June... | <urn:uuid:ddd41a97-ac76-4865-839f-e2ba9799de7a> | 2.6875 | 82 | Knowledge Article | Science & Tech. | 58.531667 |
Matrix Size & Validation
What is Vector?
Vector Scalar Multiple
Vector Inner Product
Vector Outer Product
Vector Cross Product
Vector Triple Cross Product
Vector Triple Dot Product
Scalar Triple Product
Orthogonal & Orthonormal Vector
Cos Angle of Vectors
Scalar and Vector Projection
What is a matrix?
Matrix Diagonal I... | <urn:uuid:b692badd-c14a-43bf-bba0-74215118cbf7> | 3.3125 | 518 | Tutorial | Science & Tech. | 30.749643 |
by Brian Dunning.
No personality in the history of science has been pushed further into the realm of mythology than the Serbian-American electrical engineer Nikola Tesla. He is, without a doubt, one of the true giants in the history of electromagnetic theory. […] Tesla’s unparalleled combination of genius and aberrance... | <urn:uuid:3ea12622-47c4-4fdd-9e98-2daa7d1f8490> | 3.359375 | 2,391 | Listicle | Science & Tech. | 31.795435 |
The high mountain forests of western North America need fire. Fire returns nutrients to the soil and replaces old stands and ground debris with young forest. Intense fires are a characteristic of the conifer forests, though they occur infrequently—once every 100 to 300 years.
The year 1988 brought one of those infreque... | <urn:uuid:bc8e29c3-06e6-4677-ad61-6d63077192ea> | 4.5 | 357 | Knowledge Article | Science & Tech. | 42.042284 |
Part of the beauty of Haskell is that it allows you to simply write recursive functions. But part of the problem with recursive functions is that they tend to have absolutely horrible big-O run times. The usual solution to this problem is to use what’s known as memoization, which is memorization without the ‘r’, since ... | <urn:uuid:702ed4a0-2917-45ed-9cea-1faf6787209c> | 3.0625 | 1,306 | Personal Blog | Software Dev. | 61.493426 |
Simply begin typing or use the editing tools above to add to this article.
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Two other chemical families that are important in petroleum refining are composed of unsaturated molecules. In unsaturated molecules, not all the ... | <urn:uuid:c1c6f950-e24b-43cb-b7cb-37384cb58b04> | 3.625 | 167 | Knowledge Article | Science & Tech. | 30.089604 |
Chrooting has been around for a long time now. Chrooting makes a program believe that the root of the file system is higher up in the hierarchy. For example, if I wanted to create a chroot in /chroot/httpd, a program executed from within the chroot would believe that “/chroot/httpd” was actually “/”. There in lies the ... | <urn:uuid:659395bb-ecea-4133-889b-9b5918be1058> | 2.765625 | 152 | Documentation | Software Dev. | 58.531667 |
Someone once said : "Time and space are modes by which we think and not a condition in which we live." I did not get exactly what it meant. Can you help me?
It is impossible to say that two things happen at the same time. It depends on the motion of the observer. For example, suppose you were standing in your room and ... | <urn:uuid:9b1986de-84e7-4664-920c-bdb6cee78732> | 3.046875 | 422 | Q&A Forum | Science & Tech. | 58.953586 |
To test your code you're often be given testing code and you may sometimes develop your own tests. When dode tests individual methods in your class, these tests are called unit tests and so you need to use the standard JUnit unit-testing library with the appropriate Java class files to test your classes.
To choose Run ... | <urn:uuid:0344f938-3613-4c2d-a588-71d5eaccd915> | 2.796875 | 289 | Tutorial | Software Dev. | 57.910773 |
Map of the thickness of the Mt. Simon sandstone in the Illinois Basin (Image: Midwest Geological Sequestration Consortium)
Map of Illinois showing Decatur near to the center (Image: Shutterstock)
A scheme to inject 1 million tonnes of carbon dioxide under Decatur, Illinois seeks to raise public awareness of the potenti... | <urn:uuid:84eec22c-c84c-4dff-8371-ceccb8cbf3e3> | 3.1875 | 206 | Truncated | Science & Tech. | 32.359988 |
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Predicting Invasions of Nonindigenous Plants and Plant Pests
in their floras (Vitousek et al. 1996). Deliberately introd... | <urn:uuid:005446ec-c794-43b6-8d41-2d1df8f7e674> | 3.25 | 722 | Truncated | Science & Tech. | 24.998977 |
ON 9 June 1994, a remarkable earthquake struck beneath the rainforests of Bolivia. Measuring 8.3, it was the largest anywhere on Earth for almost two decades. But nobody was killed, because it took place an astonishing 640 kilometres beneath the ground. Though there have been other recorded earthquakes as deep as this,... | <urn:uuid:79886d1c-48cf-4329-a78d-1b5bdcf9c666> | 3.84375 | 210 | Truncated | Science & Tech. | 42.058553 |
posted June 19, 2007
Oxidants from Pulverized Minerals--- Laboratory measurements of hydrogen peroxide produced from crushed basaltic minerals immersed in water have important implications for Martian and lunar dust.
Written by Linda M. V. Martel
Joel Hurowitz (previously at State University of New York at Stony Brook ... | <urn:uuid:d8de570b-6c25-4338-8ed8-4cdaa4deed45> | 3.5625 | 2,317 | Academic Writing | Science & Tech. | 22.757544 |
, Brahmagupta's formula
finds the area
of any quadrilateral
given the lengths of the sides and some of their angles. In its most common form, it yields the area of quadrilaterals that can be inscribed in a circle
In its basic and easiest-to-remember form, Brahmagupta's formula gives the area of a cyclic quadrilateral w... | <urn:uuid:2082e138-886a-46f6-8bce-3eca50864f4e> | 3.703125 | 552 | Knowledge Article | Science & Tech. | 27.888803 |
Extensive alternative splicing (AS) of precursor mRNAs (pre-mRNAs) in multicellular eukaryotes increases the protein-coding capacity of a genome and allows novel ways to regulate gene expression. In flowering plants, up to 48% of intron-containing genes exhibit AS. However, the full extent of AS in plants is not yet kn... | <urn:uuid:0fe84bfc-3c0e-4be0-9a3c-565f6322ca05> | 3.015625 | 944 | Academic Writing | Science & Tech. | 48.210909 |
Tornado observed by the VORTEX-99 team on May 3, 1999, in central Oklahoma. Note the tube-like condensation funnel, attached to the rotating cloud base, surrounded by a translucent dust cloud.
Click on image for full size
Courtesy of NOAA
Before 1971, there was no way for scientists to rank tornadoes
strength. How big ... | <urn:uuid:710aaac1-2683-4e6b-837f-ed1d73f8f4d2> | 4.3125 | 714 | Content Listing | Science & Tech. | 62.406889 |
Endeavour To Begin ISS Assembly
News story originally written on November 27, 1998
NASA is going to launch Space Shuttle Endeavour on December 3rd, 1998.
The shuttle will carry the first connector for the International Space
Station. The connector is called Unity.
The Space Shuttle crew will connect the Unity module to... | <urn:uuid:e1789e42-2e71-447e-9529-a4b2520b8e92> | 2.734375 | 456 | Content Listing | Science & Tech. | 60.152202 |
Comprehensive DescriptionRead full entry
BiologyFound between the seabed and midwater on the lower continental shelf, over sand. Juveniles found in oceanic surface waters (Ref. 2683); adults normally live close to the bottom (normally in 50-350 m depth (Ref. 47377)). Gregarious. Juveniles feed mainly on pelagic inverte... | <urn:uuid:66613f0a-cf63-45aa-95f4-435ed145e45d> | 3.03125 | 129 | Knowledge Article | Science & Tech. | 43.615 |
This Mental and Oral activity revolves around number bonds (or complements) to 100.
Children work in pairs, using a mini-whiteboard. Ask them to draw a three by three grid and to quickly fill the grid with different multiples of 5. When they have completed this the teacher starts to call out random multiples of 5, chil... | <urn:uuid:c12491b1-cdf1-42f7-81cd-dbaf948237e8> | 3.625 | 99 | Truncated | Science & Tech. | 66.349451 |
Longsnout Seahorse Hippocampus reidi
Species ID: S.HR
Description: The seahorse’s elongated body is covered in bony armour and is characterized by a curving neck and horse-like head, as well as a curled prehensile tail. Body colour is variable, and can be yellow, white, brown, black or even two-toned. The body is peppe... | <urn:uuid:21bfbb30-99eb-47fb-b2fe-7bb6cb6f2141> | 2.765625 | 2,086 | Knowledge Article | Science & Tech. | 48.188593 |
HXRBS was designed to examine the role of energetic electrons in solar flares by measuring the variations in intensity and energy of the hard X-ray fluxes. Scintillation events in its actively collimated CsI(Na) detector were read out every 128 ms in fifteen energy channels between ~25 to ~500 keV. A circulating memory... | <urn:uuid:323956a7-3847-4403-bed7-8a9239d25281> | 2.90625 | 216 | Knowledge Article | Science & Tech. | 42.497806 |
By Ravi Chellam on The Hindu Folio
By the time you finish reading this issue of Folio, perhaps one more plant or animal species somewhere in the world would have disappeared. Gone forever, never to come back.
Extinction is forever. What is the significance of this pithy little phrase, oft used in conservation circles? ... | <urn:uuid:461087b9-597c-43b8-abd4-76bb77147183> | 3.71875 | 2,391 | Personal Blog | Science & Tech. | 36.418424 |
Newton's Third Law in the Framework of Special Relativity
Newton's third law states that any action is countered by a reaction of equal magnitude but opposite direction. The total force in a system not affected by external forces is thus zero. However, according to the principles of relativity a signal can not propagat... | <urn:uuid:2a114258-d956-4492-bed5-9171da813050> | 3.671875 | 156 | Academic Writing | Science & Tech. | 27.537469 |
Tim the Plumber wrote:
The idea that you can predict the climate based on it's temperature behaviour between 1970 and 1998 is silly. Just as the statement that the absence of warming since 1998 and 2011 cannot utterly disproove AGW the rise between 1970 and 1998 cannot 100% proove the theory that CO2 is a significant g... | <urn:uuid:19f0ac3e-e73a-454a-9cba-d004cc56a732> | 2.703125 | 746 | Comment Section | Science & Tech. | 54.915009 |
THE nightmare scenario goes like this. Farmers blanket their fields with crops engineered to carry genes designed to defeat pests and disease. The crops pass these genes on to wild relatives, turning them into supercompetitive weeds that rampage through the countryside, wiping out rare and vulnerable plant species. The... | <urn:uuid:f187529e-4ab3-4fa6-a69b-74749b4c962b> | 2.703125 | 226 | Truncated | Science & Tech. | 56.996393 |
My co-authors and I have just published an article in Nature Geoscience (advance online publication here; associated press release here) which seeks to explain certain enigmatic features of tree-ring reconstructions of Northern Hemisphere (NH) temperatures of the past millennium. Most notable is the virtual absence of ... | <urn:uuid:fe0b2b98-bcf6-4f0d-bddc-00d8720667e2> | 2.875 | 2,287 | Academic Writing | Science & Tech. | 26.372584 |
Archimedes and the “buoyant force”
September 6, 2010 | In: Science facts
While stepping into a public bath in the third century B.C., the Greek scientist Archimedes noticed how submerging his foot caused water to run over the side. He realized that the volume of water displaced was equal to the volume of the object sub... | <urn:uuid:79325936-8aa3-41b1-b2df-baa3c169b5a1> | 3.765625 | 318 | Knowledge Article | Science & Tech. | 56.513197 |
Common Names in English:
White-clawed Crayfish, Atlantic Stream Crayfish, River Crayfish, White-footed Crayfish
Typically found in a lake at a mean distance from sea level of 129 meters (424 feet).
This is a freshwater
species which can be found under submerged cobbles
, and amongst fallen leaves in permanent water
bod... | <urn:uuid:41598c1c-9950-4c7d-93ca-918fc60f6d9a> | 3.59375 | 2,361 | Knowledge Article | Science & Tech. | 57.662015 |
(Submitted December 22, 2010)
Mature elliptical galaxies have been spotted 1 billion years after the
big bang. Considering that the stars within these type of galaxies should
be at least 10 billion years old, and assuming that the same laws of physics
apply to the early universe as apply to the present universe, why do... | <urn:uuid:8cf7a824-978b-4bcc-9ab0-9be62505b2cd> | 3.5 | 199 | Q&A Forum | Science & Tech. | 34.423088 |
Description: The beautiful Red-eyed Tree Frog measures up to three inches in length. It is bright green above with bluish thighs and sides. It has white underparts and orange toes. The conspicuous eyes are bright red with vertical black pupils. The frog’s bright colors are used to startle predators and allow the frog a... | <urn:uuid:d5ae4667-503f-44dd-b227-59acaeec365e> | 3.640625 | 397 | Knowledge Article | Science & Tech. | 53.491857 |
Artist's impression of GOCE (Gravity field and steady-state Ocean Explorer) satellite.
Eyes in the sky
18 May 2012
Sending satellites into orbit isn't a hobby for the cheapskate. Each launch costs millions, and if anything goes wrong on the way up you can kiss that cash goodbye.
But for every dollar spent, satellites p... | <urn:uuid:c3e1947b-8291-4dbd-a71f-e0fd48c1d2a3> | 3.734375 | 666 | Knowledge Article | Science & Tech. | 36.116551 |
This paper was written as part of the 2010 Alaska Oceans Sciences Bowl high school competition. The conclusions in this report are solely those of the student authors.
Effects of Polar Ice Melt on Ocean Chemistry and Kodiak Island's Economy and Energy Technology
Weapons of Bass Destruction
Global and regional climate c... | <urn:uuid:7da0e320-595e-4a2a-a4de-09e7ee003c84> | 2.96875 | 3,367 | Academic Writing | Science & Tech. | 39.00601 |
Exclusive: No ice at the North PoleFrom a June 20 National Geographic article:
Polar scientists reveal dramatic new evidence of climate change
By Steve Connor, Science Editor
Friday, 27 June 2008
It seems unthinkable, but for the first time in human history, ice is on course to disappear entirely from the North Pole th... | <urn:uuid:a149c4bf-8743-432a-9132-ef04097b54bf> | 3.359375 | 559 | Personal Blog | Science & Tech. | 51.209718 |
First, a brief description of what Bloom filters are. They’re a data structure that relies on hash functions for representing a set. The actual structure is a bunch of bits and a few hash functions. To add an element to a Bloom filter, compute the hashes for each hash function, and set each bit high. To test if an elem... | <urn:uuid:8cfcbeee-3319-4132-b3b8-fd12527c05df> | 2.765625 | 405 | Documentation | Software Dev. | 71.442548 |
Water Temperature Data for Tantalus Creek Upstream from the Reservoir, Yellowstone National Park
This site collects water from all parts of the Norris Geyser Basin except The Gap and Hundred Springs Plain. The temperature is measured immediately prior to where the Creek enters the lake-like water body known as The Rese... | <urn:uuid:6b51d056-2465-41d5-b053-0f872fd77032> | 3.828125 | 175 | Knowledge Article | Science & Tech. | 23.041525 |
What surrounds a hotbed of star formation?
In the case of the
Orion Nebula -- dust.
entire Orion field, located about 1600
light years away, is inundated with intricate and
picturesque filaments of dust.
Opaque to visible light,
dust is created in the outer atmosphere of massive
cool stars and expelled by a strong oute... | <urn:uuid:d35746ef-a60b-4de4-9bbc-5ad0d11aab1b> | 4.1875 | 159 | Knowledge Article | Science & Tech. | 48.87 |
|Are the nearest galaxies distributed randomly? A plot of over one million of the brightest "extended sources" detected by the Two Micron All Sky Survey (2MASS) shows that they are not. The vast majority of these infrared extended sources are galaxies. Visible above is an incredible tapestry of structure that provides ... | <urn:uuid:32c44709-fa4c-4d33-95b0-49f9a48cbdd6> | 3.34375 | 151 | Truncated | Science & Tech. | 39.641606 |
Bar-headed geese in high-flying wind tunnel test
Video footage of bar-headed geese in high-altitude wind tunnel experiments has been released by researchers.
The flights were captured in super slow-motion by the University of British Columbia.
During "test flights", birds wear masks they are trained to wear as goslings... | <urn:uuid:eab844b6-9f5f-4640-813d-0bfba4bdd9cb> | 3.109375 | 641 | Truncated | Science & Tech. | 45.591341 |
This week's book giveaway is in the General Computing forum. We're giving away four copies of Arduino in Action and have Martin Evans, Joshua Noble, and Jordan Hochenbaum on-line! See this thread for details.
Builder and Bridge patterns solve a different purpose. Builder pattern is used when the construction of an Obje... | <urn:uuid:7e80ad45-790c-49a4-bd05-547169497b28> | 2.84375 | 203 | Comment Section | Software Dev. | 56.709449 |
The Twin Paradox
The “twin paradox” is not a paradox in the sense of a logical contradiction that falsifies relativity but rather a very curious puzzle. Traditionally, the twin paradox is concerned with the strange result that if one of two twin brothers leaves the other and embarks on a high-speed journey to a remote ... | <urn:uuid:9e58a6a9-f4db-4617-b6ea-96c79680718e> | 3.328125 | 1,565 | Knowledge Article | Science & Tech. | 57.88212 |
Warp Speed 10: NASA Physicist Says Warp Drive is Feasible
September 18, 2012 1:10 PM
comment(s) - last by
Adjustments have radically reduced the theoretical amount of energy necessary to warp space-time
"There is hope."
Those were the words of Harold "Sonny" White at the
100 Year Starship Symposium
, an event where sci... | <urn:uuid:1e9a4e50-963d-411c-98c0-56e10a6449de> | 2.75 | 1,596 | Comment Section | Science & Tech. | 55.277238 |
Biodiversity is the diversity within a species, between different species, and the total diversity present in an ecosystem. Extinction of species lessens the biodiversity of the ecosystem in addition to having an impact beyond the local environ.
How do species become extinct?
It is generally accepted by scientists that... | <urn:uuid:d4c16220-fdb2-4340-b2a2-2683cf1f272d> | 4.15625 | 1,172 | Knowledge Article | Science & Tech. | 36.840607 |
1. Fluid Dynamics
This section discusses the analysis of fluid in motion - fluid dynamics. The motion of fluids can be predicted in the same way as the motion of solids are predicted using the fundamental laws of physics together with the physical properties of the fluid.
It is not difficult to envisage a very complex ... | <urn:uuid:3e21e89c-3f40-4f7e-8246-b443478962e5> | 3.734375 | 1,154 | Tutorial | Science & Tech. | 47.745637 |
The next time you see something flapping in the breeze on an overhead power line, squint a little harder. It may not be a plastic bag or the remnants of a party balloon, but a tiny spy plane stealing power from the line to recharge its batteries.
The idea comes from the US Air Force Research Lab (AFRL) in Dayton, Ohio,... | <urn:uuid:01cd8515-4678-4ced-b153-e169e6264b65> | 2.859375 | 2,347 | Comment Section | Science & Tech. | 57.183292 |
Trinitrotoluene is one of the most commonly used explosive materials by military forces. One of the big reasons for this is that it's very resistent to shocks and friction, which makes it difficult to detonate.
Because of this, TNT was originally ignored as an explosive material and actually used as a yellow dye! Event... | <urn:uuid:b50a7655-1f9f-4845-9244-af3acd35e4a6> | 2.953125 | 126 | Knowledge Article | Science & Tech. | 37.484466 |
Magnesium (Mg) and its alloys are attractive for use in automotive and aerospace applications because of their low density and good mechanical properties. However, difficulty in forming magnesium and the limited number of available commercial alloys limit their use. Powder metallurgy may be a suitable solution for form... | <urn:uuid:83c0b31c-5249-472d-9761-17edba8745cd> | 2.96875 | 419 | Academic Writing | Science & Tech. | 41.349598 |
by Rick Groleau
Whether it's in the form of burning tobacco or a raging forest fire, combustion is merely some material rapidly combining with oxygen. Well, maybe that's stating it too simply. Combustion turns out to be a complex interaction between molecules—even the burning of a simple five-atom molecule can involve ... | <urn:uuid:3a88dfec-e21e-4719-9548-0b375c391613> | 3.6875 | 293 | Truncated | Science & Tech. | 27.704185 |
int close (fd) int fd;
close() deletes a descriptor from the per-process object reference table. If fd is the last reference to the underlying object, then the object will be deactivated. For example, on the last close of a file the current seek pointer associated with the file is lost. On the last close of a socket (s... | <urn:uuid:c1fa8544-5cf4-46bf-93c5-9ba379bf8dfd> | 3.484375 | 578 | Documentation | Software Dev. | 60.012568 |
to be an experimental feature. Use in production applications is not recommended. See the Perl provides a fork() keyword that corresponds to the Unix system call of the same name. On most Unix-like platforms where the fork() system call is available, Perl's fork() simply calls it.
On some platforms such as Windows wher... | <urn:uuid:79ef383c-5bcf-48e7-8c82-2622c9ee95c3> | 3.609375 | 1,641 | Documentation | Software Dev. | 39.045029 |
More than 80% of all stars are members of multiple star systems containing two or more stars. Exactly how these systems are formed is not well understood. Some are thought to form when a collapsing cloud of gas breaks apart into two or more clouds which then become stars, or when one star captures another as a result o... | <urn:uuid:2249c2c2-c2e5-4930-9e49-909b496e7dc7> | 4.15625 | 671 | Knowledge Article | Science & Tech. | 45.761533 |
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.
2007 February 13
Explanation: The explosion is over but the consequences continue. About eleven thousand years ago a star in the constellation of Ve... | <urn:uuid:747ccad0-e65d-43a8-a6c0-494e6da33d0a> | 3.765625 | 261 | Knowledge Article | Science & Tech. | 40.196318 |
Neil C. Swart and Andrew J. Weaver, Nature Climate Change, 2, 2012
About the commentary
Developing the Alberta oil-sands will lead to carbon emissions that in turn result in global warming. Our paper calculates the amount of warming the oil-sands could potentially cause. We also consider how oil-sands carbon emissions ... | <urn:uuid:1714426f-f0ff-41d1-84aa-0ff10b13cecb> | 3.234375 | 966 | Academic Writing | Science & Tech. | 43.152428 |
Strings are represented in DTrace as an array of characters terminated by a null byte (that is, a byte whose value is zero, usually written as '\0'). The visible part of the string is of variable length, depending on the location of the null byte, but DTrace stores each string in a fixed-size array so that each probe t... | <urn:uuid:61a4c751-17e4-408c-8d21-e2be9d378f2d> | 3.6875 | 407 | Documentation | Software Dev. | 46.306377 |
Flies, gnats, maggots, midges, mosquitoes, keds, bots, etc. are all common names for members of the order Diptera
. This diversity of names documents the importance of the group to man and reflects the range of organisms in the order. The order is one of the four largest groups of living organisms. There are more known... | <urn:uuid:028fa3aa-658a-4865-86af-9d451226d740> | 3.9375 | 353 | Knowledge Article | Science & Tech. | 44.898713 |
What is it?
Chaos is an advanced field of mathematics that involves the study of dynamical systems, that is, systems in motion.
Chaos Theory consists of the mathematical proofs and theories which attempt to describe processes in motion.
One example of a chaotic dynamical system is the motion of the stars, planets, and ... | <urn:uuid:65d104f2-a70e-41c9-81d8-a1480e57875d> | 3.71875 | 339 | Knowledge Article | Science & Tech. | 52.198784 |
If there are five points on a circle. How many line segments can be drawn on it, but without overlapping the regions?
The number of line segments you can draw, each segment joining two of the 5 points on a circle, no two segments intersecting except at the 5 points, is 7. The five line segments that join the 5 points i... | <urn:uuid:0162b1c5-2e1d-48b4-99a7-a4b4a09ff8c1> | 3.21875 | 142 | Q&A Forum | Science & Tech. | 66.557948 |
A coin is tossed 4 times. Let X be the number of heads in the first two tosses and Z be the number of heads in the last three tosses. Describe the joint distribution of (X,Z) by means of a table.
I know how to find the joint distribution of two independent random variables but I'm not sure how you'd go about with this ... | <urn:uuid:b0e7d62a-7aa9-44d8-b702-a636f793f15f> | 2.859375 | 104 | Q&A Forum | Science & Tech. | 79.75 |
Elephant fishes (English), Mormyrids, mormyre (French)
With more than 200 species in 20 genera, the Family Mormyridae is a modern radiation within the Osteoglossomorpha, an ancient lineage of teleost fishes in which most other living groups are species-poor. Mormyrids are found only in Africa, in freshwater habitats ov... | <urn:uuid:80a030ec-dc53-4155-8bac-3032b6806286> | 3.671875 | 3,625 | Knowledge Article | Science & Tech. | 40.345021 |
In one case I had to determine whether an individual had consumed cocaine before death. I wondered whether I could use the maggots, beetles, and pupa that had inhabited the body and test them for drugs. The answer turned out to be yes.
Drug use has skyrocketed in the last ten years, as have drug related homicidesso mor... | <urn:uuid:6dd16b67-e267-44d8-b113-3ab3ddb9ac96> | 3.125 | 1,152 | Audio Transcript | Science & Tech. | 56.15124 |
How many different journeys could you make if you were going to
visit four stations in this network? How about if there were five
stations? Can you predict the number of journeys for seven
Your challenge is to find the longest way through the network
following this rule. You can start and finish anywhere, and with
any ... | <urn:uuid:a053de61-7f2b-4e62-a291-797549eaefd1> | 2.921875 | 1,586 | Content Listing | Science & Tech. | 71.804803 |
Aug 14, 2000, 1:40 PM
Post #2 of 3
The @new array is left unchanged at
5, 2, 4, 8;
How? I don't have my books handy, but i think it goes something like this.
First the call is made to Sort::cure, where
$a and $b are package global variables. These should be qualified with the package name of the caller, since the sort ... | <urn:uuid:7e96e770-de5f-4206-84b9-0318d29a5354> | 2.78125 | 168 | Comment Section | Software Dev. | 73.165519 |
Carl Hewitt’s Same-Fringe Problem
August 3, 2010
Long ago, Carl Hewitt created the same-fringe problem as a demonstration of the simplest problem that requires concurrency to implement efficiently: Given two binary trees, determine if they have the same leaves in the same order, regardless of their internal structure. ... | <urn:uuid:577a44e8-018c-482b-8ca9-1ccaadbd0394> | 3.046875 | 167 | Personal Blog | Software Dev. | 27.139239 |
With moral and monetary support, including a UC Proof of Concept Grant, two UC grads have formed a company to create 'printable' batteries that are efficient, environmentally friendly and could be made as small as a postage stamp.
They delivered a message to legislators: graduate student research is central not only to... | <urn:uuid:759206a5-267d-43ab-a03d-7be6f5bf369a> | 2.8125 | 950 | Content Listing | Science & Tech. | 29.39336 |
Section 2: Mysteries of Light
Figure 3: This furnace for melting glass is nearly an ideal blackbody radiation source.
Source: © OHM Equipment, LLC. More info
The nature of light was a profound mystery from the earliest stirrings of science until the 1860s and 1870s, when James Clerk Maxwell developed and published his ... | <urn:uuid:2a4bf4bf-ce34-4e88-9c13-03056f134028> | 3.90625 | 1,482 | Knowledge Article | Science & Tech. | 43.49241 |
This chapter shows you how to create cross platform tools.
If for some reason you have to stop and come back later, remember to use the su - clfs command, and it will setup the build environment that you left.
Before issuing the build instructions for a package, the package should be unpacked as user clfs, and a cd int... | <urn:uuid:953ee5dd-8f6e-46ac-a24c-af6d55a7aae6> | 2.875 | 307 | Documentation | Software Dev. | 51.763474 |
This report is a product of the Committee on Restoration of the Greater Everglades Ecosystem (CROGEE), which provides consensus advice to the South Florida Ecosystem Restoration Task Force. The Task Force was established in 1993 and was codified in the 1996 Water Resources Development Act (WRDA); its responsibilities i... | <urn:uuid:ce810ea2-4229-43f1-91c0-4db42e3c7f0c> | 3.09375 | 514 | Knowledge Article | Science & Tech. | 22.396225 |
Flying Low: The Deep Flight II sub uses stubby wings that propel it down like an airplane goes up. Nick Kaloterakis
By liberal estimates, we’ve explored about 5 percent of the seas, and nearly all of that in the first 1,000 feet. That’s the familiar blue part, penetrated by sunlight, home to the colorful reefs and just... | <urn:uuid:5646ec31-bb11-4cff-b9bb-030db9f11483> | 3.03125 | 290 | Truncated | Science & Tech. | 63.737063 |
A television camera at ground level is filming the lift-off of a rocket that is rising vertically according to the position function s=50t^2, where "s" is in feet and "t" is in seconds. The camera is 2,000 feet from the base of the launch pad. Find the rate of change in the angle of elevation of the camera 10 seconds a... | <urn:uuid:f277d70b-4b86-45ca-bc8e-712110b8f3ad> | 3.171875 | 163 | Q&A Forum | Science & Tech. | 86.845673 |
More In This Article
- Photo Album
“For almost two decades my colleagues and I have been studying one of the most remarkable systems of communication that nature has evolved. This is the ‘language’ of the bees: the dancing movements by which forager bees direct their hivemates, with great precision, to a source of food... | <urn:uuid:a5eea5bc-1784-411f-b58b-c2a663f70dd1> | 3.0625 | 894 | Truncated | Science & Tech. | 45.458359 |
Web services promote an environment for systems that is loosely coupled and interoperable. Many of the concepts for Web services come from a conceptual architecture called service-oriented architecture (SOA). SOA configures entities (services, registries, contracts, and proxies) to maximize loose coupling and reuse. Th... | <urn:uuid:5ed2fcbf-18b8-436c-9e82-ba43a2b314ac> | 3.671875 | 696 | Knowledge Article | Software Dev. | 24.418497 |
Narrator: This is Science Today.
Plant breeders are always looking for ways to create
tougher, more disease-resistant crops. A breakthrough
came recently when biologists cloned a family of
genes that give resistance to several types of plant
disease. Brian Staskawicz of the University of California,
Berkeley says the d... | <urn:uuid:8a237033-0080-4b7a-9ed4-00391021e766> | 2.984375 | 273 | Audio Transcript | Science & Tech. | 41.438011 |
A large-scale survey of brown hare Lepus europaeus and Iberian hare L. granatensis populations at the limit of their ranges
Christian Gortazar, Javier Millán, Pelayo Acevedo, Marco A. Escudero, Javier Marco & Daniel Fernández de Luco
Gortazar, C., Millán, J., Acevedo, P., Escudero, M.A., Marco, J. & Fernández de Luco, ... | <urn:uuid:0b0f54b1-30eb-4bc1-b7e0-236f075cf330> | 2.953125 | 829 | Academic Writing | Science & Tech. | 49.57881 |
Calcifying sea critters may pay the price for increasing levels of carbon dioxide in the atmosphere
Victoria Fabry and Brad Seibel study what’s come to be known as “the other CO2 problem.”
Most of us are familiar with the first problem: The copious discharge of carbon dioxide, the primary greenhouse gas, into the atmos... | <urn:uuid:403c3e6e-f757-45df-a41f-9d8b2aa85d97> | 3.53125 | 1,583 | Truncated | Science & Tech. | 35.143611 |
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.
2003 October 1
Explanation: Jon Burnett, a teenager from South Wales, UK, was photographing some friends skateboarding last week when the sky did so... | <urn:uuid:805bf6d3-3220-4ea5-ac5c-60f8afbc6b6a> | 2.796875 | 229 | Knowledge Article | Science & Tech. | 38.100658 |
Engineers find fun way to experiment with old technology
Ping Pong’s fun to play, but it’s not a great game to watch. It’s all a bit, I don’t know, repetitive. But that’s what makes this video so great—it actually makes ping pong interesting. Here’s what went down.
Mark French, a mechanical engineering at Purdue Univer... | <urn:uuid:975b5a36-ca0b-4afb-be47-b9897dff05e1> | 3.046875 | 258 | Truncated | Science & Tech. | 70.000526 |
This Identification Section was authored by:
Dr. S. Jerrine Nichols
U.S. Geological Survey
Great Lakes Research Center
1451 Green Road
Ann Arbor, MI 48105
Zebra mussels are not the only freshwater bivalve molluscs that are found in North America, nor are they the only introduced species. Because of this, it is importan... | <urn:uuid:f4ef9808-7d10-4865-97a9-62805d9df2f9> | 3.421875 | 735 | Knowledge Article | Science & Tech. | 20.723205 |
Scientists have documented for the first time that animals can and do consume Archaea – a type of single-celled microorganism thought to be among the most abundant life forms on Earth. Archaea that consume the greenhouse gas methane were in turn eaten by worms living at deep-sea cold seeps off Costa Rica and the West C... | <urn:uuid:d0d7544f-10f4-476e-bfda-3110cd1c88bd> | 3.40625 | 187 | Content Listing | Science & Tech. | 21.260845 |
If a polynomial is divided by (x+2), the remainder is -19. When the same polynomial is divided by (x-1), the remainder is 2. Determine the remainder when the polynomial is divided by (x-1)(x+2).
We know that and where and are two polynomials such that .
Thus, and .
The remainer, when dividing by can be of degree 1 at m... | <urn:uuid:73d826f6-f3b0-441f-b300-34d1d14a5f41> | 3.484375 | 170 | Q&A Forum | Science & Tech. | 70.697561 |
Name: andrew g cantrell
Date: 1993 - 1999
Is the moon ever truly full except during a total solar eclipse?
Is there a reason that the oion nebula appears blue in my telescope?
1) nope, the moon can't be full during a solar eclipse! (why?)
[perhaps you were thinking of lunar eclipses?]
2) the Orion Nebula is one of the ... | <urn:uuid:f11f64e0-d4ef-4875-81e6-1b9a42b06930> | 2.921875 | 347 | Q&A Forum | Science & Tech. | 56.638934 |
Follow humbly wherever and to whatever abyss Nature leads, or you shall learn nothing. -T.H. Huxley
We’ve spent a little bit of time talking about dark energy, including what we think of it, how we first discovered it, and how we knew that there wasn’t just something out there blocking the light. It seems to be the lat... | <urn:uuid:6531b9af-a17a-4b83-a4f0-288bb8a99070> | 3.109375 | 624 | Personal Blog | Science & Tech. | 54.004553 |