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Landing a space vehicle on a celestial body devoid of atmosphere, such as the moon, presents special technical problems of braking the vehicle’s descent and accurately controlling the braking action. The conditions of entry are different from those presented by a major planet enveloped in a relatively dense atmosphere.... | <urn:uuid:febbb094-0f0c-413c-8664-7bd833078b09> | 4.0625 | 1,243 | Tutorial | Science & Tech. | 53.111057 |
Division of Energy
Wind Energy Resources
- Small Wind Energy Systems, Fact Sheet--PUB2313 (02/09)
- Net Metering and the Easy Connection Act, Fact Sheet--PUB2238 (02/08)
- Wind Energy Public Forums (2008 forums)
- Missouri Wind Energy Workgroup
- Wind Energy Internet Resources
- Missouri Anemometer Loan Project Initial... | <urn:uuid:01ee7460-aca1-4437-8f41-388b1e52af9d> | 3.09375 | 1,270 | Knowledge Article | Science & Tech. | 59.956723 |
Albert Einstein (1879 - 1955) was a theoretical physicist, philosopher and author who is
widely regarded as one of the most influential and best known scientists and intellectuals of all time. He is often
regarded as the father of modern physics. He received the1921 Nobel Prize in Physics "for his services to
Theoretic... | <urn:uuid:72bfe07d-350c-45be-91a3-375e332e8a97> | 3.515625 | 817 | Content Listing | Science & Tech. | 38.520259 |
The swallow-tailed kite is a graceful raptor with a seemingly effortless soaring ability, making it a favorite among birder-watchers. March to September is the optimum time to spot a swallow-tailed kite in the Southeastern U.S.
The kite leaves its wintering habitat in northern South America, taking various migration ro... | <urn:uuid:67c8ccaa-4c7e-4e5a-92ab-27c57afe12e9> | 3.609375 | 671 | Knowledge Article | Science & Tech. | 29.352027 |
Algae and Pond Maintenance
From WikiAlgae thrive during the spring season and the dog days of summer. Algae can be revealed in several shapes and pigments. Green algae are the most typical kind of pond algae. They are ancient plants similarly analogous to fungi. They don’t have any real leaves, stems, or roots. They mu... | <urn:uuid:14dcebc6-708a-4caf-931a-cb78751e0d00> | 3.0625 | 704 | Knowledge Article | Science & Tech. | 46.823886 |
Water conservation involves the reduction in usage of water as well as the recycling of waste water for various purposes, including cleaning, manufacturing, and agricultural irrigation. A major issue for both consumers and industry alike, water conservation is increasingly important in a world with a rapidly growing po... | <urn:uuid:eab4bebb-2495-4698-ba1c-605a99bcea73> | 3.34375 | 919 | Content Listing | Science & Tech. | 52.893429 |
These images show thermal infrared radiation from Jupiter at different wavelengths which are diagnostic of physical phenomena The 7.85-micron image in the upper left shows stratospheric temperatures which are elevated in the region of the A fragment impact (to the left of bottom). Temperatures deeper in the atmosphere ... | <urn:uuid:4f4fbc49-35b9-4b75-a181-2b9d088399fa> | 2.734375 | 184 | Knowledge Article | Science & Tech. | 39.971524 |
Binary tree in C++
Simple, may not be the best implementation there is. Contains functions for inserting, deleting, finding the next and previous values, checking if a node is a leaf, printing, searching, counting the number of nodes, etc.
Also contains a main with examples. Nice for beginners.by cohenman on 29 May 110... | <urn:uuid:7925921b-30ee-4b37-b959-8d7b3b4cd1a7> | 3.5625 | 940 | Content Listing | Software Dev. | 64.945003 |
Add a wee bit of science to your St. Patrick's Day pranks and celebration with these fun chemistry projects.
1. Green Fire
Wasn't there green fire in Disney's 1959 movie "Darby O'Gill and the Little People"? If not, there should have been. Eldritch green fire screams Irish and St. Patrick's Day.
2. Dye Beer Green
Use f... | <urn:uuid:323da947-8c6c-4d92-8a27-1fd86ecd6954> | 2.890625 | 353 | Listicle | Science & Tech. | 78.386329 |
The Rise and Full of the Space Shuttle
JANUARY 28, 1986 proved to be the blackest day in the history of human adventure into outer space. On this cragic'day^all the seven crew mertibers perished in the 25th space shuttle mission (Mission S\ -L) and the 10th flight of the space shuttle Challenger. This single accident l... | <urn:uuid:28f7c17b-b2b1-4092-b697-2e82a6e9d8a6> | 3 | 507 | Knowledge Article | Science & Tech. | 42.138277 |
Comprehensive data on the chemical element Fluorine is provided on this page; including scores of properties, element names in many languages, most known nuclides of Fluorine. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains... | <urn:uuid:71121a48-1a96-4b2f-b59c-07a9f60622eb> | 3.046875 | 156 | Structured Data | Science & Tech. | 41.070769 |
The following completion functions have nothing in themselves to do with minibuffers. We describe them here to keep them near the higher-level completion features that do use the minibuffer.
This function returns the longest common substring of all possible completions of string in collection. The value of collection m... | <urn:uuid:fcfa693d-ed38-4799-9fe6-6e18eb694aa7> | 2.6875 | 1,877 | Documentation | Software Dev. | 48.890526 |
The answer would be actually much simpler if the collapse produced a black hole. It can be easily shown to have entropy vastly exceeding the entropy of any gas of the same mass.
Concerning your main question, the answer is, of course, that any system with many degrees of freedom - both in classical physics as well as q... | <urn:uuid:e04de9e8-7334-4092-adf8-2aa18a9908f3> | 3 | 380 | Q&A Forum | Science & Tech. | 30.086538 |
Sakurajima in Japan erupting in 2000.
Sometimes, it is the volcanoes that erupt out of the blue that get all the attention, leaving the ones that are constant producers to be ignored by the fawning media. Sakurajima in Japan is just one of those constant erupting volcanoes that doesn’t get its just due. Well, over the ... | <urn:uuid:6369f140-58df-44d1-9d88-39819f731987> | 2.78125 | 394 | Personal Blog | Science & Tech. | 36.208476 |
How do you decide what to call a variable? Many conflicting constraints come to bear on this question. I want to communicate my intent fully through my names, which often suggests long names. I’d like the names to be short to simplify code formatting. Names will be read many times for each time they are typed, so the n... | <urn:uuid:6a7be0a1-2998-4609-8c7b-52b6e62609ce> | 2.78125 | 723 | Documentation | Software Dev. | 44.840567 |
Statistics and Probability Dictionary
Select a term from the dropdown text box. The online statistics
glossary will display a definition, plus links to other
related web pages.
Statisticians distinguish between two broad categories of
Probability sampling. With probability sampling, every element
of the population has ... | <urn:uuid:3b74db44-8647-4ad0-b3fc-3a940516850c> | 2.984375 | 152 | Structured Data | Science & Tech. | 20.503226 |
|Did Lacis et al try to turn the control knob up to 12 out of 10?|
The links for the article are http://www.tswj.com/2012/761473/ and the journal itself - http://www.tswj.com/contents/
Emeritus Faculty, Australian National University, Canberra, ACT 0200, Australia
Academic Editor: Donald H. Stedman
Copyright © 2012 Tim... | <urn:uuid:8df44685-07eb-468c-baac-39810e8dba4b> | 2.71875 | 376 | Truncated | Science & Tech. | 33.002879 |
Texas Leafcutting Ant (Atta texana)
Anonymous. 1989. Insects and Diseases of Trees in the South. USDA Forest Service. Protrotection Report R8-PR16. 98 pp.
The Texas leafcutting ant, or town ant, is a serious pest of pine regeneration in the upland areas of west central Louisiana and east Texas. It does not occur in oth... | <urn:uuid:9a498d3c-7f7b-410d-8f1a-ca64d3f64965> | 3.390625 | 381 | Knowledge Article | Science & Tech. | 58.094139 |
Hydrogen produced from water using aluminium and gallium
Jerry Woodall describes a method of producing hydrogen using water, aluminium and gallium.
Robyn Williams: A couple of weeks ago we brought you research at the University of Queensland using algae to produce hydrogen. Now another promising means using aluminium. ... | <urn:uuid:97e17ba5-0bda-4db4-93c9-c868b77d6bff> | 3.390625 | 1,409 | Audio Transcript | Science & Tech. | 57.593308 |
Glycolipids are carbohydrate-attached lipids. Their role is to provide energy and also serve as markers for cellular recognition.
They occur where a carbohydrate chain is associated with phospholipids in the cell surface membrane. The carbohydrates are found on the outer surface of all Eukaryotic cell membranes.
They e... | <urn:uuid:d5f170db-420d-403b-bc95-db94ea59aab0> | 3.34375 | 116 | Knowledge Article | Science & Tech. | 22.185 |
The general steps to creating a widget in GTK are:
gtk_*_new() - one of various functions to create a new widget. These are all detailed in this section.
Connect all signals and events we wish to use to the appropriate handlers.
Set the attributes of the widget.
Pack the widget into a container using the appropriate ca... | <urn:uuid:1cbee8df-fc09-44a7-ae35-605ba7b6da1f> | 3.140625 | 592 | Tutorial | Software Dev. | 54.54262 |
Explanation: Comet Halley was photographed superposed in front of the disk of our Milky Way Galaxy in 1986 by the Kuiper Airborne Observatory. Comet Halley is the bright white streak near this photograph's center. Comet Halley is the most famous comet in history, and returns to the inner Solar System every 76 years. St... | <urn:uuid:0213db70-2957-4ecd-948e-7f19d711e212> | 4.03125 | 139 | Knowledge Article | Science & Tech. | 53.050385 |
While refining their novel method for making nanoscale wires, chemists at the National Institute of Standards and Technology (NIST) discovered an unexpected bonus—a new way to create nanowires that produce light similar to that from light-emitting diodes (LEDs). These "nano-LEDs" may one day have their light-emission a... | <urn:uuid:fa4a1afe-18bb-47c6-a3ef-0b76286235c5> | 3.15625 | 900 | Content Listing | Science & Tech. | 25.964471 |
The impact of biological invasions on the food web of the Wadden Sea (INFOWEB)
09 / 2011 - unknown
To demonstrate the impact of invasive species on the food web of the Wadden Sea three characteristic areas with a different degree of invasive impact will be analysed with respect to the food web, the status of the system... | <urn:uuid:5243c6fd-d3dd-41fb-97b8-7d2b65e2170a> | 2.984375 | 635 | Academic Writing | Science & Tech. | 21.621425 |
The major species groups, habitats and processes detailed below were selected for analysis in the assessment because they play critical roles in supporting diverse marine life. Within the species groups, specific species or habitat types were identified to represent the ecosystem of the Northwest Atlantic.
There are se... | <urn:uuid:d3a4b31e-6bbc-4ea3-bbf7-d6ebbed08771> | 4 | 882 | Knowledge Article | Science & Tech. | 26.201502 |
4. METHOD OF SOLUTION
The code is run interactively and the user examines the output and chooses what he feels to be the best values for the number of resonances to be considered and for D noting for example that at the higher energies resources may have been missed through lack of resolution, which leads to a steady i... | <urn:uuid:b2a5b824-28c6-48db-a504-5f7e9596200b> | 3 | 302 | Documentation | Science & Tech. | 27.819643 |
Hi I'm Dave Thurlow and this is The Weather Notebook. As the summer fire season draws to a close, listener Eileen Williams of Grand Haven Michigan has a question about the cause of some of the worst forest fires in history. She listens to the Weather Notebook on Michigan Public Radio from Ann Arbor-Grand Rapids. Here's... | <urn:uuid:1985f759-7675-4d70-8eb6-64d30a7df2b1> | 3.375 | 391 | Audio Transcript | Science & Tech. | 67.57565 |
More Images of Cepheus B
Labeled Image of Cepheus B
A new study suggests that star formation in Cepheus B is mainly triggered by radiation from one bright, massive star (HD 217086) outside the molecular cloud. According to the particular model of triggered star formation that was tested -- called the radiation-driven i... | <urn:uuid:ebbf8119-fe2b-4d81-835b-18d0bb477184> | 3.671875 | 529 | Knowledge Article | Science & Tech. | 63.865645 |
Transmutation and Radioactivity
Transmutation of one elementA substance containing only one kind of atom and that therefore cannot be broken down into component substances by chemical means. into another requires a change in the structures of the nuclei of the atomsThe smallest particle of an element that can be involv... | <urn:uuid:00cff7ac-3994-4a56-9260-e0dfd1b431e2> | 4 | 1,054 | Knowledge Article | Science & Tech. | 38.241028 |
The challenge is to write an interpreter for the untyped lambda calculus in as few characters as possible. We define the untyped lambda calculus as follows:
There are the following three kinds of expressions:
A lambda expression has the form
(λ x. e)where
xcould be any legal variable name and
eany legal expression. Her... | <urn:uuid:57d0928e-7251-472e-9879-f0623e72a271> | 3.4375 | 1,061 | Documentation | Software Dev. | 77.139358 |
Lessons and tutorials in the Programming Language C.
Branching Statements (if, else, switch) :
The if statement :
The if statement allows you to control if a program enters a section of code or not based on whether a given condition is true or false.
An if statement includes the keyword if followed by a logical express... | <urn:uuid:f0384579-5fb8-4363-8ab5-301b81dcf678> | 4.375 | 167 | Tutorial | Software Dev. | 47.246791 |
Although we still haven’t found any biological activity elsewhere, it’s hardly inconceivable that before your car gets its next oil change, robot spacecraft could discover a horde of microbes hidden beneath the Martian sands. Or maybe a few years down the road, some astrobiology experiment will stumble across alien pon... | <urn:uuid:0969d2b5-81d7-406c-b629-44a3e5ceff71> | 3.046875 | 664 | Personal Blog | Science & Tech. | 36.689179 |
Arctic Blog: A Place for Wildlife
By Steve Zack, Wildlife Conservation Society
In the National Petroleum Reserve
26 Jul 2011
During my four-night stay at our remote Ikpikpuk camp, we were serenaded virtually nonstop by a Smith’s longspur, a songbird usually found in the Brooks Range and adjacent foothills, some 60 mile... | <urn:uuid:518ad9ce-b236-44be-92ce-0f06d904d298> | 2.75 | 1,593 | Personal Blog | Science & Tech. | 44.305274 |
ANSI Common Lisp 21 Streams 21.2 Dictionary of Streams
sequence stream &key start end
sequence - a sequence.
stream - an output stream.
start, end - bounding index designators of
sequence. The defaults for start and end are 0 and nil, respectively.
write-sequence writes the elements of the subsequence
of sequence bound... | <urn:uuid:6afa6b70-7009-49a9-9e44-b13eb41f1e1f> | 2.6875 | 299 | Documentation | Software Dev. | 46.424334 |
See also the
Dr. Math FAQ:
Browse High School Higher-Dimensional Geometry
Stars indicate particularly interesting answers or
good places to begin browsing.
Selected answers to common questions:
Do cones or cylinders have edges?
Latitude and longitude.
MaximizIng the volume of a cylinder.
- Relative Motion on Face of Ea... | <urn:uuid:aaf01d32-81a9-4dea-bc6c-6514bd29c826> | 3.46875 | 1,800 | Q&A Forum | Science & Tech. | 66.546636 |
Copyright © University of Cambridge. All rights reserved.
A large container holds 14 litres of a solution that is 25% antifreeze, the remainder being water. How many litres of antifreeze must be added to the container to make a solution that is 30% antifreeze?
If you liked this problem, here is an NRICH task which chal... | <urn:uuid:e98f76e1-caf7-4543-acdc-9ce087219c70> | 3.015625 | 102 | Tutorial | Science & Tech. | 47.041491 |
Scientists have been using small variations in the Earth’s gravity to identify trouble spots around the globe where people are making unsustainable demands on groundwater, one of the planet’s main sources of fresh water.
They found problems in places as disparate as North Africa, northern India, northeastern China and ... | <urn:uuid:668ba6dd-2241-47db-8996-861c75dad937> | 3.09375 | 255 | Personal Blog | Science & Tech. | 32.8628 |
Earth's biodiversity is mostly in the tropics, and most tropical species can survive within only a narrow temperature range. That's because the environment they're adapted to is fairly constant year-round.
As global temperature warms, tropical animals are likely to feel the effects in unpredictable ways. Perhaps most a... | <urn:uuid:67a4b9e5-1f35-4a44-83c5-498a3c877407> | 4.25 | 356 | Knowledge Article | Science & Tech. | 37.212973 |
How small insects survive the rain
Scientists have found that mosquito’s tiny, low-weight body, is the key to its ability to survive flying in the rain.
This showed that their bodies put up so little resistance that, rather than the drop of water stopping in a sudden, catastrophic splash, the mosquito simply combined w... | <urn:uuid:c0ade91a-c8c1-4c41-ac11-b0023005fbf3> | 3.375 | 989 | Truncated | Science & Tech. | 57.052684 |
Concept 21 RNA is an intermediary between DNA and protein.
Francis Crick describes RNA and its role and Paul Zamecnick explains protein synthesis.
Hello, I'm Francis Crick. The story of DNA does not end with Watson and me solving its three-dimensional structure. Because DNA is the hereditary molecule of the cell, we re... | <urn:uuid:81257009-efe2-4ae0-8cd3-e4d866607c39> | 3.5625 | 1,636 | Knowledge Article | Science & Tech. | 44.764535 |
New Zealand has 3,820 lakes over one hectare in size and many more that are smaller. Less than 40 lakes are greater than 1,000 hectares in size. [Based on the database of lakes produced by NIWA for developing a lake classification system.] The largest lake in New Zealand is Lake Taupo with an area of about 62,000 hecta... | <urn:uuid:879367d1-790a-4269-97cf-746935e66393> | 3.828125 | 1,411 | Knowledge Article | Science & Tech. | 36.117053 |
COULD sulphur traces on Jupiter's moon Europa be a sign of alien life? The compounds look like waste products rising from bacterial colonies living beneath the surface.
The Galileo space probe first spotted the sulphur compounds, as well as revealing that the moon almost certainly has a volcanically heated and potentia... | <urn:uuid:f680816b-d1fc-4bc8-89fc-8131c4a0b00a> | 3.921875 | 216 | Truncated | Science & Tech. | 41.095725 |
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Water From Where?
Sat Nov 21 20:58:38 GMT 2009 by anonymous
Part 1 of 2
Wondering: Great question!
Consider what water is composed of: each water molecule is made up of 2 hydrogen atoms attached to an oxygen atom.
The hydrogen atoms part is easy: they were formed directly out of the big ... | <urn:uuid:30b772e6-e75a-4b19-8158-fff9448e065e> | 2.96875 | 805 | Comment Section | Science & Tech. | 33.944619 |
“Impossible colors,” or “forbidden colors,” are hues that cannot be seen by the human eye in ordinary viewing conditions. These are actually simpler to describe than one might think.
In our color wheel, we have colors like “red-orange” or “blue-green.” These colors exist because they are right next to each other on the... | <urn:uuid:d60fd8e3-fd6e-4219-bda0-9151d38059d8> | 3.296875 | 221 | Knowledge Article | Science & Tech. | 55.752955 |
Home page Stardust Email me
Five space-filling polyhedra
The main text of this article is reproduced by kind permission from:
The Mathematical Gazette 80, November 1996, p.p. 466-475.
Some changes have been made from the original as follows:
10 January 2010. Links to Maurice Starck's page updated.
18 October 2006. Prin... | <urn:uuid:00c239e4-abb3-4fd3-8156-38cf1dc6367e> | 2.875 | 2,519 | Academic Writing | Science & Tech. | 48.266676 |
"Mammals could be in for a stormy ride and face a greater risk of extinction due to predicted increases in extreme weather conditions, according to a paper published today by the Zoological Society of London (ZSL).
Scientists have mapped out land mammal populations and combined this with their knowledge of where drough... | <urn:uuid:3bff5b37-1982-48ae-9f00-0c29d6fcb42a> | 3.25 | 296 | Comment Section | Science & Tech. | 37.045698 |
What kind of telescopes are used to look farthest into space? Is it radio telescopes?
Radio waves are electromagnetic radiation, according to Wikipedia. Does that mean that radio waves fall under the domain of quantum physics?
That's what I wish to know for now.
Both optical and radio -- as well as ultraviolet, x-ray, ... | <urn:uuid:460c0ffe-5634-4706-8e45-9a1f093575ef> | 3.515625 | 413 | Q&A Forum | Science & Tech. | 48.115714 |
Summary: The orientation and sedimentary structure of sand dunes depend on the strength and direction of the prevailing winds, so ancient dunes should contain important clues to paleoatmospheric circulation patterns--if their ages can actually be determined. Preusser et al. (p. 2018) used difficult luminescence techniq... | <urn:uuid:b43b0daf-2e0f-4bd9-a59c-275189055a37> | 3.1875 | 189 | Truncated | Science & Tech. | 28.119394 |
It is related to volume fraction by dividing by 100%.
A solution consists of a solvent, which is commonly a liquid, and a solute, which may be any substance that dissolves in the solvent. For example, if salt water (a solution) is distilled, water (the solvent) passes over into the receiver and salt (the solute) remain... | <urn:uuid:af7e3f08-a9ff-4401-bcf9-e4a2d0b8859c> | 3.609375 | 229 | Knowledge Article | Science & Tech. | 44.988288 |
Home Effects Global Warming Preventions Diversity Collaboration Works Cited
What Causes Global Warming?
Global Warming- an increase in the Earth's average surface temperature.
Our earth is heated by the rays of the sun. As the sun shines down on us, energy from the heat reflects off of the earth, into space. Gases from... | <urn:uuid:9d48c669-48d5-4a61-bb06-2d399a186f44> | 3.25 | 230 | Knowledge Article | Science & Tech. | 57.391048 |
In the x direction: 160 N + 250*0.96 = 400 N
In the y direction: 370 N - 250*0.28 = 300 N
Unfortunately he/she didn't add them correctly and got the wrong components.
To finish the problem from here we are looking for a vector R such that x + y + R = 0. (Note carefully what direction R is in!)
As far as the angle 97.1,... | <urn:uuid:dafb3002-6750-4994-9f89-44e88182ce20> | 3.015625 | 138 | Q&A Forum | Science & Tech. | 108.624113 |
Figure 3 summarizes our description of reradiation from gas and dust in the host galaxy of a quasar. Provided quasars are located in galaxies like those of their lower luminosity cousins, it is hard to imagine how thermal reradiation can fail to make a significant contribution to the infrared luminosity of quasars. As ... | <urn:uuid:e5477d5b-c8bd-4c7f-816f-4c5ea4a40bd7> | 2.96875 | 687 | Academic Writing | Science & Tech. | 33.570287 |
Rendering Microsoft Tags in .tag Format
Rendering a Microsoft Tag in the .tag file format provides a hexadecimal code that you can use to programmatically generate the Tag in other applications. This documentation explains how to interpret the hexadecimal encoding of a Tag and how to generate a scannable graphic.
Downl... | <urn:uuid:1c386670-a388-4bf5-b55a-d57ef4ac5676> | 2.953125 | 3,041 | Documentation | Software Dev. | 57.267628 |
More abstractly, a charge is any generator of a continuous symmetry of the physical system under study. When a physical system has a symmetry of some sort, Noether's theorem implies the existence of a conserved current. The thing that "flows" in the current is the "charge", the charge is the generator of the (local) sy... | <urn:uuid:b248d5f5-db76-41e3-a97a-0ad44aaaab04> | 3.453125 | 537 | Knowledge Article | Science & Tech. | 37.314881 |
|More About JUDGING HAZARDS
Lava flows from andesitic and rhyolitic magmas rarely
cover more than a few square kilometers because of their
high viscosity. More viscous lava comes to the surface
fairly slowly, so lava flows don't travel very far before
cooling and slowing. If large quantities of lava are
extruded quickl... | <urn:uuid:b00ac2f3-20b2-4d0f-8c68-349b567583a4> | 4.375 | 612 | Knowledge Article | Science & Tech. | 40.209742 |
A depiction of the vast "Fermi Bubbles" of gamma-ray emitting magnetic fields emanating from above and below the center of our Milky Way galaxy. / NASA's Goddard Space Flight Center
Vast radiation-emitting "bubbles" erupting from the center of the Milky Way spring from rapid star formation there over the last 10 millio... | <urn:uuid:eb8c7f04-8e5f-4c58-9af4-3a5fc9f04f0a> | 3.984375 | 405 | Truncated | Science & Tech. | 42.629279 |
When Google went public, the founders Sergey Brin and Lawrence Page suddenly joined the ranks of the world's wealthiest men.
Anyone wishing to imitate their success would first have to get hold of a gigantic computer and then create a catalog of all the world's websites. There are currently ...
This is an article from ... | <urn:uuid:8bf00d08-26d4-4a84-afd6-d878f1eafe79> | 2.9375 | 1,318 | Truncated | Science & Tech. | 52.563104 |
The mexican jumping death spider is a very peculiar kind of spider indeed. The name is misleading, as this spider is native to the Waterloo region. The rest of its name comes from the fact that as a direct result of the spider jumping, it dies.
The mexican jumping death spider will only die if it intends to jump, and m... | <urn:uuid:da4c8f4c-1c03-49a0-be9d-c563f5a15cc0> | 2.953125 | 649 | Knowledge Article | Science & Tech. | 61.880362 |
Dinoflagellates are an important group of phytoplankton that produce oxygen in marine and freshwater. Some species form symbiotic relationships with larger animals, including corals (zooxanthellae), jellyfish, sea anemones, nudibranchs and others. Sometimes dinoflagellates grow out of control, to more than a million ce... | <urn:uuid:6d41f949-cfa4-490d-9795-a68d0c8d2a17> | 3.453125 | 133 | Knowledge Article | Science & Tech. | 20.786 |
2008/9 Schools Wikipedia Selection. Related subjects: Chemical elements
The alkali metals are a series of elements comprising Group 1 ( IUPAC style) of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). (Hydrogen, although nominally also a member of Group 1, ve... | <urn:uuid:10d49e97-7a24-42a8-ad4a-227de4c49b1b> | 3.953125 | 1,863 | Knowledge Article | Science & Tech. | 33.759138 |
Scientific Name:Ascidiella aspersa
Common Name:Euorpean sea squirt (others: dirty sea squirt, solitary ascidian)
Established Range:On the East Coast, from the Bay of Fundy to Cape Hatteras
Established in Rhode Island?Yes, throughout Narragansett Bay
Date and Location of Introduction:1970's, New England
Method of Introd... | <urn:uuid:e0419b97-6ccb-40ad-8476-01cb0c228794> | 3.640625 | 507 | Knowledge Article | Science & Tech. | 36.00957 |
Rhizomes of mangrove swamps are unique in the sense that they can deal with water as well as drought. They can adapt to low levels of oxygen as well as limit their intake of salt. Furthermore, mangroves protect coastlines from erosion by waves.
Adaptation is really the word of the day concerning mangroves.
3 Responses... | <urn:uuid:0417d380-52ee-4b6a-aaec-acf6d1cf9fae> | 2.859375 | 99 | Personal Blog | Science & Tech. | 53.569 |
The Spitzer Space Telescope is a technological marvel, featuring many innovations never before used on a space mission. It stands about 4 meters (13 feet) tall, and weighs approximately 865 kilograms (1,906 pounds).
Since Spitzer is designed to detect infrared radiation, or heat - its detectors and telescope must be co... | <urn:uuid:7bcf8f2b-27c0-4325-99cd-dd767ebc5f91> | 4 | 223 | Knowledge Article | Science & Tech. | 22.036583 |
Data from Venus - On Dec. 14, 1962, NASA's Mariner 2 spacecraft sailed close to the shrouded planet Venus, marking the first time any spacecraft had ever successfully made a close-up study of another planet. It flew by Venus as planned at a range of 34,762 km (21,600 miles), scanning the planet's atmosphere and surface... | <urn:uuid:fe73cd02-7b30-45ee-aa8d-265586e4f1dc> | 3.796875 | 180 | Truncated | Science & Tech. | 51.803844 |
The concept of global warming is compelling, but how can last year's cold winter fit into that pattern?
—Bill Price, Madison, Wis.
First, short-term cooling (a few years) does not contradict the concept of global warming — longer-term trends are what count; and second, one must consider the planet as a whole. Last year... | <urn:uuid:9a1e50fd-78c0-4e1f-b5a2-e208f0544c7f> | 3.234375 | 165 | Q&A Forum | Science & Tech. | 48.994706 |
Here's our next installation in our occasional series on the Chandra blog called "The Unexpected." These posts will take a look at some of the biggest surprises (and expected discoveries) made by Chandra so far in its mission. Today's topic is "normal stars," which is what astronomers call stars that are similar to our... | <urn:uuid:b317bc38-2cf5-403b-94fa-ad3fdb8df3a9> | 3.3125 | 1,235 | Personal Blog | Science & Tech. | 40.941168 |
In languages like C or C++, the programmer is responsible for dynamic allocation and deallocation of memory on the heap. In C, this is done using the functions malloc() and free(). In C++, the operators new and delete are used with essentially the same meaning; they are actually implemented using malloc() and free(), s... | <urn:uuid:31b50666-7c3e-47f9-be08-06838571a219> | 3.640625 | 643 | Documentation | Software Dev. | 39.578747 |
This module provides an interface to the mechanisms used to implement the import statement. It defines the following constants and functions:
(suffix, mode, type), where suffix is a string to be appended to the module name to form the filename to search for, mode is the mode string to pass to the built-in open() functi... | <urn:uuid:fbb7bb7a-e2a6-4996-903e-36af912bd3e9> | 2.859375 | 899 | Documentation | Software Dev. | 39.072013 |
Actin and myosin
- Study guide:
- Wikipedia article: Myosin
Myosins are mechanochemical enzymes and motor proteins that function through ATP hydrolysis.
Myosin Structure
Myosin is composed of heavy chains and light chains. The heavy chains have head, neck and tail domains. The head domain binds actin and has ATPase ac... | <urn:uuid:eb9a902b-5b7b-49d2-88d3-a2c49f8a6133> | 3.40625 | 793 | Knowledge Article | Science & Tech. | 42.92625 |
Displaying 21 - 30 of 30 resources in Wildlife and Publications:
21. Nature Essays by Robert Winkler
Columns by Robert Winkler about his encounters with birds and other wildlife in the "suburban wilderness" of New England. ...
22. Nature's Holism - the coevolutionary mechanism
Stanger, kzn, South Africa
Nature's Holism... | <urn:uuid:180362a6-bf3b-43f6-b881-0a6ebc5c649b> | 2.75 | 369 | Content Listing | Science & Tech. | 35.387452 |
It is known that the area of the largest equilateral triangular
section of a cube is 140sq cm. What is the side length of the cube?
The distances between the centres of two adjacent faces of another
cube is 8cms. What is the side length of this cube? Another cube
has an edge length of 12cm. At each vertex a tetrahedron... | <urn:uuid:f56fd6ba-4e6d-4824-af3b-cd2734b710d9> | 2.71875 | 175 | Tutorial | Science & Tech. | 60.0315 |
What mechanisms exist for generating lift on a static object? Condition is: Other than propellers I know that generating lift on a static object in a sense of anti-gravity for e.g. drone is not ...
This air plane just caught my eye. Two contrails apparently are flowing backward, slightly off-centered and then ultimatel... | <urn:uuid:e1975562-da4d-45e0-be8a-ac8eaa2c7da7> | 3.484375 | 300 | Q&A Forum | Science & Tech. | 70.579559 |
Short note: This made some big headlines recently. Scientists have been able to encode digital information into DNA molecules. Here are four headlines that all report on the same paper from Science, but with a few different details each. They’re all great articles.
Headline from Science:
“DNA: The Ultimate Hard Drive”
... | <urn:uuid:83067ef4-c44c-4f45-84f3-90299012c400> | 3.046875 | 1,039 | Personal Blog | Science & Tech. | 67.543862 |
Modern programming practices and computer languages (like .NET) tend to dynamically create and destroy objects at run-time, but how does it correlate with multi-core-enabled programming? A parallel program may need to synchronize both lifetime of- and access to- an object in shared memory.
Known methods suffer from eit... | <urn:uuid:c50597e7-2f10-4159-94b3-d2e47a0576e4> | 2.9375 | 859 | Documentation | Software Dev. | 26.960892 |
I figure that since I’m going to Dartmouth on Monday (my title and abstract aren’t posted, unfortunately), I should finally say something about what I do. Rather than dive right in, I’ll just talk about knots.
A knot is a mathematical idealization of a tangled-up loop of string in space. Formally, it’s a (smooth) path ... | <urn:uuid:9205d4c9-b993-4c76-8334-acda268cce23> | 2.71875 | 1,099 | Personal Blog | Science & Tech. | 66.923978 |
Sunspots are dark spots that migrate across the surface of the sun. Astronomers believe that the spots on the sun are actually electrical and magnetic. Sunspots appear to be whirlwinds of electrified matter bursting out from the sun's interior. They shoot beams of negatively charged electrons into space, some of which ... | <urn:uuid:335bc4e5-9414-48a4-8b44-6a5369052d9b> | 4.375 | 366 | Knowledge Article | Science & Tech. | 61.456035 |
Gators Breathe Like Birds
Did Dinosaur's Ancestors Inhale their Way to Dominance?
Before and until about 20 million years after the extinction - called "the Great Dying" or the Permian-Triassic extinction - mammal-like reptiles known as synapsids were the largest land animals on Earth.
The extinction killed 70 percent ... | <urn:uuid:cbc8c4e2-aeaf-4ff2-9893-4624d9612529> | 3.59375 | 1,554 | Knowledge Article | Science & Tech. | 38.730817 |
On a dry winter day, if you scuff your feet
across a carpet, you build up a charge and get
a shock when you touch a metal doorknob.
In a dark room you can actually see a spark
about 2 cm long. Air breaks down at a field
strength of 3 × 106 N/C.
Assume that just before the spark occurs,
all the charge is in your finger,... | <urn:uuid:80dbb581-b0f7-411a-a65b-5b873653a199> | 3.140625 | 161 | Q&A Forum | Science & Tech. | 85.09822 |
During our recent study of chemistry, I had my eighth grade students create a comic strip of a rather complicated experimental method. They drew this comic strip across the white board at the front of the room. Each class contributed a section of the comic, and also improved on sections previously created. By the end o... | <urn:uuid:bc96257a-3c3d-426f-b685-b909cb058151> | 3.171875 | 263 | Personal Blog | Science & Tech. | 55.752021 |
Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Pomacentridae
(Damselfishes) > Pomacentrinae
Etymology: Pomachromis: Greek, poma, -atos = cover, operculum + Greek, chromis = a fish, perhaps a perch (Ref. 45335).
Environment / Climate / Range
Marine; reef-associated; non-migratory; depth range 3 - 12 m ... | <urn:uuid:627b6710-2b17-4262-a5fe-f0646135945f> | 3.046875 | 492 | Knowledge Article | Science & Tech. | 61.203919 |
"Tags" are a listing of code objects in a group of files, together with their precise location, often used by text editors to quickly jump around in a program. ctags (for C) was the first tag-generation program.
There are currently a number of different ways to generate tags with Haskell.
This page should be used to co... | <urn:uuid:233d6682-e9d6-4573-8df8-804cefd275ab> | 2.703125 | 315 | Documentation | Software Dev. | 58.91521 |
What would the gravitational potential energy be if the bucket were raised six times as high?
If you do 110 J of work to elevate a bucket of water, how much energy did you add to the gravitational field?
A boulder is raised above the ground so that the gravitational potential energy relative to the ground is 360 J. The... | <urn:uuid:8033ad54-9a0d-40f7-b3cd-2f464e83e9d6> | 2.921875 | 385 | Content Listing | Science & Tech. | 88.063138 |
Catarina Hits Brazil
image (328 Kb)
2004, only two tropical cyclones had ever been noted in the South
Atlantic Basin, and no hurricanes. In late March 2004, a circulation
center well off the coast of southern Brazil developed tropical
cyclone characteristics and continued to intensify as it moved westward.
The system d... | <urn:uuid:e5ab71e7-55dc-4976-b865-f88e704af866> | 3.53125 | 289 | Truncated | Science & Tech. | 23.753105 |
THE "green flash" sky that watchers sometimes report at sunset is often all in the mind, a scientist from California reported last week. While some green flashes are true mirages, he says, others are probably caused by the effect of bright light on our colour vision.
As the Sun sinks below the horizon, observers someti... | <urn:uuid:70cfdfaa-6f5b-435c-ac28-e166a786442a> | 3.265625 | 202 | Truncated | Science & Tech. | 59.9511 |
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Looking for a great physics site? We've tracked down the very best and checked them for accuracy. Just fill out the fields below and we'll do the rest.
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PostNatural Organism of the Month:
Sterile Male Screwworm
During the late 1950's a large-scale public works program was initiated to eradicate the live-flesh-eating screwworm plaguing cattle ranches across the American south. The screwworm is the larval stage of the fly, Cochliomyia hominivorax. Full-scale fly factorie... | <urn:uuid:b3c9db41-c12e-4282-81c5-396b88383008> | 3.015625 | 231 | Knowledge Article | Science & Tech. | 22.310426 |
Solar System with Snug Suns
This artist's concept depicts a faraway solar system like our own except for one big difference. Planets and asteroids circle around not one, but two suns. NASA's Spitzer Space Telescope found evidence that such solar systems might be common in the Universe.
Spitzer did not see any planets d... | <urn:uuid:c5cc5157-0da7-43e6-beaf-89ff05ff1d34> | 3.5 | 166 | Knowledge Article | Science & Tech. | 52.59 |
The biggest physics experiment ever, CERN’s Large Hadron Collider (LHC), goes live this summer. The international project, whose design was approved in 1994, cost over $6 billion. Thousands of powerful magnets, cooled by tons of liquid helium to 1.9 Kelvin (just above absolute zero), will guide two beams of protons as ... | <urn:uuid:f592b26e-9e47-425b-8952-b7218fc20c64> | 4.0625 | 248 | Truncated | Science & Tech. | 46.825417 |
U.S. Water News Online
GLOUCESTER, Mass. -- After cleaning the bottom of his boat
in the Annisquam River last September, Brad Chase dove a few feet
deeper to look at the bed of the salt water estuary, expecting a view
more like a moonscape than a seascape.
What he found surprised, awed, and disturbed him. Chase, a mari... | <urn:uuid:38f5afc7-27f6-4cc4-bd06-7c2d22e750fb> | 2.90625 | 936 | Truncated | Science & Tech. | 42.756336 |
Note: The following is a guest post by a regular reader and commenter, JohnD. You can find more of his work on his own blog, Factismals. He also performed a highly regarded review of the city’s record August, 2011 temperatures. Below, to see larger versions of the images, just click on them.
As we’ve done before, let’s... | <urn:uuid:e073c59c-e949-4004-9ca8-16c786d61900> | 2.71875 | 1,222 | Personal Blog | Science & Tech. | 51.848369 |
GOLDEN GATE CETACEAN RESEARCH
Field Studies of Porpoises, Dolphins & Whales
in San Francisco Bay and on the Coast of Northern California
Goals and Methods: Using techniques developed with minke whales in the San Juan Islands and Monterey Bay, our project will collect the following data to use as values for parameters i... | <urn:uuid:7f3dd61b-16f7-4652-ae15-3ef4ee96afe9> | 3.203125 | 343 | Academic Writing | Science & Tech. | 33.37972 |
Eastern Pacific sea surface temperature since 1600 A.D.: The δ18O record of climate variability in Galápagos Corals
Article first published online: 4 MAY 2010
Copyright 1994 by the American Geophysical Union.
Volume 9, Issue 2, pages 291–315, April 1994
How to Cite
1994), Eastern Pacific sea surface temperature since 1... | <urn:uuid:df7dfeb0-1888-4772-8967-f73070157ec8> | 2.734375 | 905 | Academic Writing | Science & Tech. | 47.365372 |
In mathematics, the number four is an even number and the smallest composite number. Four is also the second square number after one. A small minority of people have four fingers and four toes, on each hand and foot, respectively. This proves difficult to count on your fingers. Four squared is 16, and four doubled is 8... | <urn:uuid:c139036b-f13a-43aa-af1a-2ba0f19c7f57> | 2.921875 | 66 | Knowledge Article | Science & Tech. | 64.653474 |
WatchList Species Account for Florida Scrub-Jay |
Qualifies for the list as a Red List Species
Photo: Daniel J. Lebbin
Federally listed as threatened, the Florida Scrub-Jay, Florida’s only endemic bird, is found in the north and central peninsular part of the state; key sites for it include Ocala National Forest, Canav... | <urn:uuid:2c6c3888-0313-437c-ba4e-be135d249737> | 3.109375 | 468 | Knowledge Article | Science & Tech. | 40.747017 |
Lorrey, A., Williams, P., Salinger, J., Martin, T., Palmer, J., Fowler, A., Zhao, J.-X. and Neil, H. 2008. Speleothem stable isotope records interpreted within a multi-proxy framework and implications for New Zealand palaeoclimate reconstruction. Quaternary International 187: 52-75.
A master speleothem δ18O record (whi... | <urn:uuid:70ca7a70-7077-4fcd-a0a9-b5890d169eda> | 2.734375 | 183 | Academic Writing | Science & Tech. | 68.212454 |
Introduction to VxWorks Programming
Some of the rudiments of VxWorks programming are presented here.
These do not appear in the same order presented in Ref
1, which should be read by any serious VxWorks programmer.
Rather they reenforce some of the material that can be found there,
but appear in a top-down order, with ... | <urn:uuid:0831318c-4095-44b2-91a6-72df3964f557> | 2.984375 | 3,677 | Tutorial | Software Dev. | 40.764038 |
On the other hand there are numerous positive feedbacks. Particularly that higher temperatures increase the amount of water vapour in the air (7% per 1 deg C) which is again a stronger GHG than CO2. Loss of ice cover over the sea changes the surface from reflecting 90% of the radiation to absorbing in excess of 80%.
Hi... | <urn:uuid:dddf4679-f92e-4661-98d0-c67470ef2e0c> | 3.453125 | 577 | Comment Section | Science & Tech. | 44.66732 |
Water enters through a subsurface opening into a chamber with air trapped above it. The wave action causes the captured water column to move up and down like a piston to force the air through an opening connected to a turbine.
An oscillating water column device harnesses the motion of ocean waves as they pressurize a p... | <urn:uuid:5df7abbc-56aa-4ed1-b212-890a10c680c9> | 3.9375 | 255 | Knowledge Article | Science & Tech. | 33.727418 |
This is the VOA Special English ENVIRONMENT REPORT.
Doppler radar is an increasingly important tool to study weather. It is named after a physical effect first reported by an Austrian scientist, Christian Doppler. In eighteen-forty-two, he described how movement seems to influence the rate at which energy waves are pro... | <urn:uuid:bf4b2af0-358a-4486-83ad-d76dc538155a> | 4.25 | 488 | Truncated | Science & Tech. | 57.899404 |
Hurricanes are violent storms that can form over the warm waters of the oceans. The warm water heats the air above it. Warm air rises, like steam from a teakettle. The rising warm air creates an area of low pressure. Other air rushes toward the low pressure area from all directions, creating strong winds if the low pre... | <urn:uuid:4c2402a3-0b66-4a71-865a-db87ef9f3114> | 3.90625 | 354 | Knowledge Article | Science & Tech. | 57.0858 |