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Static Sub DeleteTextures ( Textures As Integer )
Delete named textures.
Specifies the number of textures to be deleted.
Specifies an array of textures to be deleted.
textures named by the elements of the array textures
After a texture is deleted, it has no contents or dimensionality,
and its na... | <urn:uuid:76c65e38-c481-4d85-b3f3-3b7edcec7a87> | 2.953125 | 176 | Documentation | Software Dev. | 42.005128 |
Only 1 species: Symbion Pandora
This animal was discovered in 1993 and was so unique it was assinged to an entirely new phylum. It lives on the mouth parts of the Norway lobster Nephrops norwegicus. The organism has a very complex life cycle, with a number of well-defined sessile and free swimming stages with a differe... | <urn:uuid:cfea4f99-e9d9-4410-b7cc-746c147a5f83> | 3.265625 | 170 | Knowledge Article | Science & Tech. | 58.854275 |
(Submitted April 09, 1997)
I'm a student of physics from Canada, and I was wondering how I could find out
about quasars on a very detailed level.
Since you know about black holes, I assume you know that quasars are a
subset of a class of galaxies called active galactic nuclei (AGN) that
are probably powered by a superm... | <urn:uuid:d590a009-1f57-4857-ae9c-e869349c16f6> | 3.328125 | 534 | Q&A Forum | Science & Tech. | 49.874348 |
The airplane above is traveling in a straight line at a constant speed. Its speed
is the distance traveled divided by the time interval. If we know how far
it is traveling in a given time we can determine its speed. We can
calculate this speed if we have two images of the plane seperated in time.
A timer is started whe... | <urn:uuid:9bca1848-63e6-43c7-95db-7af33b17bf5b> | 3.78125 | 575 | Tutorial | Science & Tech. | 63.426039 |
A formula to accompany the Birthday Problem
Let's look at the probabilities a step at a time.
Running this through a computer gives the chart below. Notice that
a probability of over .5 is obtained after 23 dates!
- For one person, there are 365 distinct birthdays.
- For two people, there are 364 different ways that
th... | <urn:uuid:aca32285-53dd-42e1-b19a-0d7edaf601fd> | 3.203125 | 255 | Tutorial | Science & Tech. | 75.163135 |
13 Physical Constants
This chapter describes the physical constants, such as the speed of light, c, and gravitational constant, G, provided by the Science Collection. The values are available in different unit systems, including the standard MKSA system (meters, kilograms, secomds, amperes) and the CGSM system (centime... | <urn:uuid:a9438fee-ebf6-48cd-b6c2-6768a413f211> | 3.546875 | 1,538 | Documentation | Science & Tech. | 77.35625 |
Meteorology: Understanding the Atmosphere Ackerman and Knox
Smoke From Central American Fires
This loop of daily (06 - 15 May 1998) GOES-8 0.65 micron visible imagery shows a widespread smoke pall over the Gulf of Mexico and the surrounding regions (note the hazy appearance of the smoke over much of the Gulf and the ad... | <urn:uuid:bec0eb5a-9d88-4132-b15e-40d3fa57520f> | 3.359375 | 202 | Knowledge Article | Science & Tech. | 47.565 |
C was made to make writing a compiler easily. It does a LOT of stuff based on that one principle. Pointers only exist to make writing a compiler easier, as do header files. Many of the things carried over to C++ are based on compatibility with these features implemented to make compiler writing easier.
It's a good idea... | <urn:uuid:5c73ef6d-41a5-448c-86a8-79d535332fef> | 3.0625 | 1,066 | Q&A Forum | Software Dev. | 58.854183 |
Many hopes are placed on the hydrogen economy, but for all those hopes, there sure aren't a lot of good ways to get hydrogen without burning a bunch of fossil fuels. But research being done at the University of Minnesota has efficiently created hydrogen from non-volatile sources such as Soybean Oil and dissolved glucos... | <urn:uuid:5a54d779-81ed-41eb-9119-e53b724f1f24> | 3.921875 | 294 | Personal Blog | Science & Tech. | 29.085856 |
Head First C# Code: Chapter 3, Objects Get Oriented
Every program you write solves a problem.
When you're building a program, it's always a good idea to start by thinking about what problem your program's supposed to solve. That's why objects are really useful. They let you structure your code based on the problem it's... | <urn:uuid:d99350c8-2c30-4deb-8e94-51a878e8ff55> | 2.828125 | 125 | Truncated | Software Dev. | 64.405248 |
Compiled by: Mats Lindegarth, Sweden
1. Extract from OSPAR Case Reports:
Initial List of Threatened and/or Declining Species & Habitats in the OSPAR Maritime Area (OSPAR 2006)
OSPAR definition for habitat mapping
“Maerl” is a collective term for several species of calcified red seaweed (e.g. Phymatolithon calcareum, Li... | <urn:uuid:7fa60b74-df24-4a41-ab2b-4e1e806b503a> | 3.484375 | 1,295 | Knowledge Article | Science & Tech. | 37.828504 |
Write a Webserver in 100 Lines of Code or Lessby Jonathan Johnson
Network programming can be cumbersome for even the most advanced developers. REALbasic, a rapid application development (RAD) environment and language, simplifies networking yet provides the power that developers expect from any modern object-oriented la... | <urn:uuid:f1e257ea-d754-453e-8914-d0b2145c1ae5> | 3.0625 | 1,822 | Tutorial | Software Dev. | 52.843757 |
Tension in an elevator cable
An elevator has a mass of 1400kg. What is the tension in the supporting cable when the elevator traveling down at 10 m/s is brought to rest in a distance of 40 m. Assume a constant acceleration.
m =1400 kg mass of elevator,
v = 10m/s initial speed of the elevator,
D = 40 m distance required... | <urn:uuid:6b2889d5-84a7-43fe-b0fa-6f22440dbaa6> | 3.09375 | 417 | Tutorial | Science & Tech. | 58.629037 |
Let's Talk About: The Bright stuff
Share with others:
Pick a star in the sky and ask yourself how bright it is. Brighter than the one next to it, perhaps? And why is it so bright? If it sounds simple, think again. It's a puzzle that astronomers say our eyes alone cannot solve. In order to truly understand the bright st... | <urn:uuid:339eb60a-5165-4b12-8940-aecbe67461a0> | 4.15625 | 410 | Truncated | Science & Tech. | 62.072304 |
Thank you for your question. I always love a good science competition. First off, let me refer you to a Science Buddies project: "Veggie Power! Making Batteries from Fruits and Vegetables" at this link:http://www.sciencebuddies.org/science-f ... background
It provides a lot of good information for an experiment of this... | <urn:uuid:4b52a7d9-3622-42d7-ba80-6dd8c99605d7> | 3.5625 | 539 | Comment Section | Science & Tech. | 57.537137 |
Editor's Note: This story is part of the Feature "Nuclear Fuel Recycling: More Trouble Than It's Worth" from the May 2008 Issue of Scientific American.
A Nuclear Renaissance?
After decades of declining interest, nuclear energy is poised for a comeback, driven by:
The quantity of spent fuel so far accumulated by the U.S... | <urn:uuid:21098da3-7eff-449e-aef2-7042455854f8> | 3.34375 | 285 | Truncated | Science & Tech. | 47.831769 |
Female Green Lynx Spiders are large green spiders with a total length measuring 11-22mm, while the males measure 8-15mm. The two sexes are similar in color and pattern. The carapace has red markings; the abdomen has several white and red chevron-shaped markings. The yellow legs have black spots.
This species occurs in ... | <urn:uuid:b3bdfca3-1dce-40bb-8fca-7c3277bc2700> | 2.984375 | 267 | Knowledge Article | Science & Tech. | 60.48371 |
WebReference.com - Excerpt from Inside XSLT, Chapter 2, Part 1 (1/4)
Trees and Nodes
When you're working with XSLT, you no longer think in terms of documents, but rather in terms of trees. A tree represents the data in a document as a set of nodes-elements, attributes, comments, and so on are all treated as nodes-in a ... | <urn:uuid:46daba4f-8423-4cba-b4d9-22b56b8e351a> | 3.625 | 631 | Truncated | Software Dev. | 62.911289 |
The troposphere is the lowest layer of Earth's atmosphere. We live in the troposphere. Weather happens in this layer. Most clouds are found in the troposphere. The next layer up is the stratosphere.
Click on image for full size
Original artwork by Windows to the Universe staff (Randy Russell).
The troposphere is the lo... | <urn:uuid:8f9af752-258f-4cff-afe6-d8ac8708ce9a> | 4.15625 | 823 | Knowledge Article | Science & Tech. | 70.480542 |
Appendix A. the ratio of Curvature Radiation (CR) to ICS power
The energy loss of a particle through CR process is:
where is the Lorentz factor of the particles, e is the electric charge of the particles, c the light of speed, is the radius of curvature of the magnetic field. The curvature radius for a dipole magnetic ... | <urn:uuid:8ea1b34f-b205-45c4-acdb-d2afe01759d0> | 3.046875 | 1,087 | Academic Writing | Science & Tech. | 51.85739 |
If you looked at the penis of a Drosophila fly under a microscope (for reasons best known only to yourself), you’d see an array of wince-inducing hooks and spines. These spines are present in all Drosophila and they’re so varied that a trained biologist could use them to identify the species of the owner.
What’s the pu... | <urn:uuid:f145ef9c-f6b4-465e-98b3-a5351a6b6f8b> | 2.75 | 236 | Personal Blog | Science & Tech. | 58.466265 |
The C++ strings library includes support for two general types of strings:
- std::basic_string - a templated class designed to manipulate strings of any character type.
- Null-terminated strings - arrays of characters terminated by a special null character.
The templated class std::basic_string generalizes how sequence... | <urn:uuid:9fe6d9f4-1ff9-4711-9750-92854dd0243c> | 3.609375 | 185 | Knowledge Article | Software Dev. | 20.348571 |
I use python 2.6
>>> hex(-199703103) '-0xbe73a3f' >>> hex(199703103) '0xbe73a3f'
Positive and negative value are the same?
When I use calc, the value is
Python's integers can grow arbitrarily large. In order to compute the raw two's-complement the way you want it, you would need to specify the desired bit width. Your e... | <urn:uuid:2172bf77-8c82-4473-8798-0f14c42c0a24> | 3.140625 | 141 | Q&A Forum | Software Dev. | 54.553 |
Supernova RemnantsThe unprecedented broad bandwidth and excellent spectral resolution of ASCA has had a major impact on all areas of research into the nature of supernova remnants (SNRs). Recent results from ASCA have increased the number of neutron star/SNR associations, debunking the decade-long mystery of the paucit... | <urn:uuid:d036f544-17ae-4f34-8dae-856b9cf70ce1> | 2.90625 | 3,752 | Knowledge Article | Science & Tech. | 58.489057 |
This paper was presented at the International Workshop on Monsoon Asia Agricultural Greenhouse Gas Emissions.
Quantifying greenhouse gas emissions from soils: Scientific basis and modeling approach
Article first published online: 31 JUL 2007
Soil Science & Plant Nutrition
Volume 53, Issue 4, pages 344–352, August 2007
... | <urn:uuid:f75a4a93-4f5c-419d-a32c-658a865e774b> | 2.9375 | 451 | Academic Writing | Science & Tech. | 25.828348 |
Mission Type: Orbiter
Launch Vehicle: Delta II 7925
Launch Site: Cape Canaveral, Fla., USA
NASA Center: Jet Propulsion Laboratory
Spacecraft Mass: 729.7 kilograms (1,608.7 pounds) total, composed of 331.8-kilogram (731.5-pound) dry spacecraft, 353.4 kilograms (779.1 pounds) of propellant and 44.5 kilograms (98.1 pounds... | <urn:uuid:4ee7e7df-c09d-46ec-8c91-1c812d9a737f> | 3.203125 | 605 | Knowledge Article | Science & Tech. | 37.741527 |
Twisted contains a large number of examples. One in particular, the "evolution of Finger" tutorial, contains a thorough explanation of how an asynchronous program grows from a very small kernel up to a complex system with lots of moving parts. Another one that might be of interest to you is the tutorial about simply wr... | <urn:uuid:bbc7cbbd-d379-4086-8303-4ae4b57b4555> | 3.046875 | 612 | Q&A Forum | Software Dev. | 51.893421 |
The rate of growth dP/dt of a population of bacteria is proportional to the square root of t, where P is the population size and t is the time in days (0 ? t ? 10) as shown below.
The initial size of the population is 500. After 1 day the population has grown to 600. Estimate the population after 7 days. | <urn:uuid:e0ecb034-5e37-468f-bb84-d016d11de826> | 2.984375 | 74 | Q&A Forum | Science & Tech. | 81.404358 |
EAC Focus - Ruth Gonzalez
Ruth Gonzalez is an expert in seismic imaging methods. Working with seismic data collected on the surface of the earth, she develops algorithms that perform calculations to produce images of the underlying geology. Since 1980, she has applied this technology to help discover oil and gas reserv... | <urn:uuid:d8b866a9-b503-42dd-9932-9c38d7cec0d1> | 2.953125 | 756 | Knowledge Article | Science & Tech. | 39.337943 |
more articles like this
Hubble Finds Farthest Protocluster of Galaxies
updated: Jan 10, 2012, 9:06 AM
NASA's Hubble Space Telescope has uncovered a cluster of galaxies in the initial stages of construction - the most distant such grouping ever observed in the early universe. An astrophysicist at UC Santa Barbara contri... | <urn:uuid:6b12e0be-08db-428c-bdbf-0af25396f6d2> | 3.4375 | 1,279 | Comment Section | Science & Tech. | 41.974538 |
Mutational Buildup Indicates Living Populations Are Young
Mutations are copy errors that degrade the information contained in DNA, which carries vital instructions for the maintenance and reproduction of cellular life. All creatures experience mutations. Very rarely, a mutational error can help some individuals in a po... | <urn:uuid:de1567b4-ed3b-44ca-9c27-eccf6ae67cd2> | 3.765625 | 281 | Knowledge Article | Science & Tech. | 22.710843 |
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which are separate from plants, animals, and bacteria. This fungal group is distinct from the structurally simi... | <urn:uuid:1e908638-5183-4c0d-919b-689f489568bd> | 3.734375 | 1,475 | Knowledge Article | Science & Tech. | 35.907018 |
World's First Supercavitating Boat?
"For decades, researchers have been trying to build boats, submarines, and torpedoes that make use of supercavitation — a bubble layer around the hull that drastically reduces friction and enables super-fast travel.
Now a company in New Hampshire called Juliet Marine Systems has buil... | <urn:uuid:d02e171b-cc78-423d-9278-205cae15eeaf> | 2.84375 | 3,602 | Content Listing | Science & Tech. | 49.521505 |
Joined: 16 Mar 2004
|Posted: Wed Jan 07, 2009 11:34 am Post subject: Renewable Energy:Small Solution for Big Electricity Problem
A Small Solution For a Big Electricity Problem
Rice University faces an uphill battle trying to help the renewable power generation industry take on one its toughest challenges.
The problem i... | <urn:uuid:b4679a8d-3a93-4a0f-9f68-6aa8f38d1d00> | 2.828125 | 1,288 | Comment Section | Science & Tech. | 38.732854 |
Because escape responses are so critical, the nerve fibers that control them in many invertebrates tend to be especially large. The tail-flick escape response of crayfish, which is often successful, is mediated by such “giant” nerve fibers. But even those giant fibers are no match for a shrew’s myelinated fibers. And s... | <urn:uuid:f4c0c209-67d2-4a62-8a1b-c7e2513f68b4> | 3.953125 | 685 | Nonfiction Writing | Science & Tech. | 41.717308 |
SQUEEZING human proteins out of plants could soon be easier than tapping latex from rubber trees, say biotechnologists who have learnt to make the roots of tobacco plants express human genes.
Many human proteins, such as antibodies, are already produced in cultures of plant cells. But these cultures require an expensiv... | <urn:uuid:9672d83c-6c9a-4941-854a-63093bd47e0d> | 3.75 | 213 | Truncated | Science & Tech. | 48.077416 |
The Large Hadron Collider is the largest and most complex scientific instrument ever built and the highest energy particle accelerator in the world.
The accelerator is located 100 m underground and runs through both French and Swiss territory. ( 27km circumference)
Year 2008 September 10th, marks the culmination of 20 ... | <urn:uuid:d50b7c33-895b-42aa-86c0-ee87550ca5ca> | 3.171875 | 249 | Personal Blog | Science & Tech. | 71.208477 |
In other words, the 1st parameter of the loop declares and initialises a variable (fl) to 10. The loop then executes the 2nd parameter, which is a logical check. It basically says "if FL is less-than-or-equal-to 150". If this statement is a true statement, it will execute the body of the loop (sum = sum + fl) and will ... | <urn:uuid:25b653b4-04c9-44c8-867b-a67027148a11> | 3.203125 | 169 | Comment Section | Software Dev. | 79.39228 |
Polar Bears Need Love
…And a plan.
A team of leading polar bear ecologists called for nations to make plans now for dealing with ongoing—and soon to be critical—threats to the survival of polar bears. The biggest problem for this iconic Arctic species is the mindblowingly fast disappearance of sea ice. Their paper appe... | <urn:uuid:f3d1071f-e656-44a3-9878-66d34b9a9122> | 2.8125 | 163 | Truncated | Science & Tech. | 57.188992 |
1. What progresses have been made recently (last 15 years) in new propulsion system research ? Rockets and their principle, that's 1500 years old, at least ! True that the Chinese were using them mainly for fireworks and the Europeans for weapons (what else ? ...), still to my knowledge nothing really new was applied t... | <urn:uuid:3d2e6056-cdfe-45de-a497-523e845bac82> | 2.765625 | 323 | Comment Section | Science & Tech. | 69.613214 |
For this year’s microgravity project we will be working with the Jet Propulsion Laboratory (JPL) and Cbana Labs in the development of a volatile organic compound (VOC) monitor that can be used in space. A VOC is a device that measures the air quality of the environment and helps detect hazardous gases. One way to do th... | <urn:uuid:7505ae73-8d3d-411d-89f4-5cfb12b7faef> | 3.421875 | 315 | Personal Blog | Science & Tech. | 46.754199 |
Brief SummaryRead full entry
BiologyThe kingfisher feeds mainly on fish and invertebrates, which it catches by perching on a convenient branch or other structure overhanging the water, and plunging into the water when suitable prey comes within striking distance (2). If a suitable perch is not present, individuals may ... | <urn:uuid:7ac89103-eb75-4595-81b3-6acd49bd6201> | 3.25 | 204 | Knowledge Article | Science & Tech. | 52.649006 |
Pipelining is sending multiple requests over a socket and receiving the responses later, in the same order. This is faster than sending one request, waiting for the response, then sending the next request, and so on. This implementation returns a promise (future) response for each request that when invoked waits for th... | <urn:uuid:3d6a3b9a-7dae-4fba-af6b-b5d62cb61236> | 2.890625 | 262 | Documentation | Software Dev. | 34.337469 |
1.3. Population systemPopulation system (or a life-system) is a population with its effective environment.
The term "life-system" was introduced by Clark et al. (1967). Later, Berryman (1981) suggested another term "population system" which is definitely better. A short review of the life-system methodology was publish... | <urn:uuid:e046f103-1edb-4f22-9635-bcc25526d684> | 3.40625 | 1,415 | Academic Writing | Science & Tech. | 37.638245 |
The Dawn spacecraft launched 27 September 2007. After completing an initial check-out phase in December 2007, Dawn began its interplanetary cruise phase which included a gravity assist from Mars in February 2009 that put the spacecraft on a trajectory to rendezvous with the asteroid 4 Vesta in July 2011. After observin... | <urn:uuid:db244010-b65e-48b7-babf-f3fd0e7e1116> | 3.140625 | 322 | Knowledge Article | Science & Tech. | 43.323386 |
It is known that many present-day species of bee maintain a symbiotic (help one another) relationship with various species of bacteria of the genus Bacillus within their gut (normal gut flora for some bees, just as E. coli bacteria are normal members of our gut flora). It is also known that Bacillus is one genus of bac... | <urn:uuid:2c11219f-a17b-4d68-8127-14fc14fa7db0> | 3.734375 | 945 | Knowledge Article | Science & Tech. | 38.301604 |
"Hello, World!" in Python With Tkinter
Most every modern application has a graphic user interface (GUI). For Python, Tkinter is the most commonly available graphic interface toolkit simply because it comes with every installation of Python. This introduction shows how to say "Hello, World!" with Tkinter.
An Introductio... | <urn:uuid:a5732513-6708-4b65-8ce2-934a070c721f> | 2.8125 | 635 | Content Listing | Software Dev. | 52.774675 |
Images and animations courtesy NASA/Goddard Space Flight Center Scientific Visualization Studio.
animation (4 MB MPEG)
As Hurricane Ignacio was churning in the waters near Baja, California, the TRMM and GOES satellites captured this image. The accompanying visualization zooms down to the storm and peels away the clouds... | <urn:uuid:3a416617-186d-4558-8e07-b966d5330b90> | 2.765625 | 125 | Truncated | Science & Tech. | 37.978409 |
XML was designed to transport and store data.
To learn more about XML, read our XML tutorial.
XML 1.0 became a W3C Recommendation 10. February 1998.
XML 1.0 (SE) became a W3C Recommendation 6. October 2000. The second edition is not a new version, but an update and a "bug-fix".
The third edition is not a new version, b... | <urn:uuid:6ed2dcbd-a343-4111-b390-3d4cf0eb0f81> | 3.171875 | 625 | Knowledge Article | Software Dev. | 103.865714 |
Take a Trip to a Zoo of Insects
Many insects are known by common names that may be based on behavior or refer to some obvious characteristic of the insect. Some of these names are suggestive of other animals — animals that are common in zoos.
There are insects called water scorpions. They are among a group of insects t... | <urn:uuid:1b0e2188-bbb4-4390-976c-6874fca15538> | 3.3125 | 620 | Knowledge Article | Science & Tech. | 55.577831 |
Sponsored Link •
Object and class locks
As described above, two memory areas in the Java virtual machine contain data shared by all threads. These are:
If multiple threads need to use the same objects or class variables concurrently, their access to the data must be properly managed. Otherwise, the program will have un... | <urn:uuid:42523e1b-0bbb-4f5c-94f6-4e59c8c6c73e> | 3.875 | 543 | Documentation | Software Dev. | 61.932318 |
IMAGE: Red, yellow-green, and green pea aphids. Photo courtesy of Charles Hedgcock, R.B.P., via NPR.
Over at the Agricultural Biodiversity Weblog, an Edible Geography favourite, Jeremy links to a fascinating post about transgenic pea aphids. The pea aphid has been the focus of quite a bit of biological excitement latel... | <urn:uuid:ddf6fe1f-2ebf-4988-9960-a82460f8ddc3> | 3.578125 | 1,132 | Personal Blog | Science & Tech. | 28.613536 |
Family within the order Proboscidea, named by Gray 1821.
The family of elephants developed during middle Miocene (16 million years ago) with its ancestor Primelephas. The first mammoths (genus Mammuthus) appeared about 3 million years ago in africa. 120 000 years ago they started to migrate to northern europe, and adap... | <urn:uuid:bc8da107-d263-47d8-8241-1f2166907798> | 3.390625 | 236 | Knowledge Article | Science & Tech. | 27.908957 |
FW: RE [Haskell-cafe] Monad Description For Imperative Programmer
wagner.andrew at gmail.com
Wed Aug 1 11:31:45 EDT 2007
> "an IO monad is a delayed action that will be executed as soon as that action is needed for further evaluation of the program."
I'm not sure I like this, as it seems to confuse the issue. An expert... | <urn:uuid:08e527dc-bab2-4841-b27f-15a5b11f5c66> | 2.828125 | 334 | Comment Section | Software Dev. | 69.950909 |
The Hawaii Natural Energy Institute (HNEI) has carried out research and development (R&D) on biological hydrogen production since the early 1990s. Initially, this project investigated the genetics of cyanobacterial (blue green algae) hydrogenases. A new R&D phase was initiated in 1996 to develop a microalgal indirect b... | <urn:uuid:7c81db18-2fff-4edf-ba32-2ab6c0018f50> | 2.9375 | 296 | Knowledge Article | Science & Tech. | 23.461638 |
Climate—The mean state of the atmosphere over a long period of time. This period is generally at least 30 years, to produce a statistically significant sample and to avoid shorter term variability. The principal elements of climate are the same as the principal elements of weather (IPCC 2007a).
Climate change—Alteratio... | <urn:uuid:629f783b-d94e-4309-a70e-ecec34e00671> | 3.671875 | 477 | Knowledge Article | Science & Tech. | 30.511394 |
It takes millions of years for a star to form but the video above captures part of the process in action. Astronomer Patrick Hartigan and his team from Rice University in Houston, Texas stitched together images from NASA's Hubble Space Telescope taken over a period of 14 years. They reveal jets of gas being ejected fro... | <urn:uuid:0e24eb60-96ed-43b4-a40a-650fb2ae2f48> | 3.875 | 367 | Truncated | Science & Tech. | 59.813687 |
Elasmobranch Reproduction and Mating System Evolution
The collapse of shark populations has resulted from the inability of shark recruitment to keep up with the intense exploitation these animals are experiencing worldwide. Sharks (and elasmobranchs in general) are particularly vulnerable to overexploitation due to the... | <urn:uuid:9ae2c00a-aac1-4b2c-9896-dfb4120bdaa0> | 3.890625 | 641 | Knowledge Article | Science & Tech. | 31.095067 |
Get flash to fully experience Pearltrees
Introduction This is not a lesson like the others in Radioactivity and Atomic Physics Explained but it fits in well with the lesson on nuclear power . It is a very sophisticated simulation of a pressurised water reactor (PWR), which is the most common type of nuclear power react... | <urn:uuid:40361a0d-9b62-4630-8c10-59500acf2807> | 3.5 | 171 | Truncated | Science & Tech. | 40.7825 |
Visit The Physics Classroom's Flickr Galleries and enjoy a photo overview of the topic of refraction and lenses.What About Astigmatism?
Learn about astigmatism at Microscopy University.LTU Physlet: Optics Model for a Far-Sighted Eye (with corrective lenses)
Use this Java applet to explore the correction for a farsighte... | <urn:uuid:23f786a0-f381-444e-ab08-482285a9fc7d> | 3.953125 | 706 | Knowledge Article | Science & Tech. | 41.882169 |
Nucleosynthesis is the process of creating new atomic nuclei from preexisting nucleons (protons and neutrons).
The primordial preexisting nucleons were formed from the quark-gluon plasma of the Big Bang as it cooled below ten million degrees.
This first process may be called nucleogenesis, the genesis of nucleons in th... | <urn:uuid:01060fad-8967-457d-8913-34dc751bb494> | 3.765625 | 160 | Knowledge Article | Science & Tech. | 32.681667 |
The most famous is probably Saturn's moon Mimas.
Image Credit JPL/NASA/CaltechDeath Star anyone? Mimas is also cool because that massive crater (the laser cannon), would have almost shattered the entire moon.
Credit: NASA, ESA, P. Kalas, J. Graham, E. Chiang, E. Kite (University of California, Berkeley), M. Clampin (NA... | <urn:uuid:357112d5-8c31-48b1-8c92-611930d438e7> | 2.921875 | 402 | Personal Blog | Science & Tech. | 59.039369 |
Originally posted by: ga14
How do you determine if a function is periodic or not without graphing it?
For example, cos^2(2pit) is periodic, as is sin^3(2t). But e^(-2t)cos(2pit) is nonperiodic, as is the discrete signal x[n]=cos(2n).
Does this have to do with Fourier series somehow? Is there an easier way to determine ... | <urn:uuid:7f135483-3287-4cd8-90f5-6f927d976b3f> | 2.984375 | 292 | Comment Section | Science & Tech. | 66.370388 |
LBA REGIONAL DERIVED SOIL PROPERTIES, 0.5-DEG (ISRIC-WISE)Entry ID: lba_isric_wise
Abstract: The data set consists of a subset of the ISRIC-WISE global data set of derived soil properties for the study area of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) in South America (i.e., longitude 85 to 30 d... | <urn:uuid:b3a1ad9f-9031-4a8f-8286-01ea03c968ae> | 2.796875 | 677 | Content Listing | Science & Tech. | 52.121731 |
HISTORY OF THE METHODS/FLOW CHART
ABOUT THE AUTHOR/CV
Multiple Arrivals in Wave Propagation
Level set methods and Fast Marching Methods are designed to track a propagating interface, and find the first arrival of the interface as it passes a point. One way to think about this is to imagine that the front's boundary is ... | <urn:uuid:8e2c67ea-1e73-4ca4-8e42-b2f0422ef03a> | 3.734375 | 792 | Academic Writing | Science & Tech. | 27.006338 |
Writing a Windows PowerShell Formatting File
"Writing a Windows PowerShell Formatting File" is for command developers who are writing cmdlets or functions that output objects to the command line. Formatting files define how Windows PowerShell displays those objects at the command line. This documentation provides an ov... | <urn:uuid:5ff13c2f-e38d-4947-bac8-65bc3bc05bf3> | 3.046875 | 278 | Documentation | Software Dev. | 27.260132 |
|Dominant Cropland Irrigation Water Source, 1997|
|Source: Natural Resources Conservation Service|
This shaded polygon map shows the dominant water source for irrigated cropland for each 8-digit hydrologic unit. Water sources are categorized by 1) Well, 2) Pond, Lake, or Reservoir, 3) Stream, Ditch, or Canal, 4) Lagoon... | <urn:uuid:9528b4e2-7c00-4ce7-8fa0-36c6999d3818> | 3.59375 | 263 | Knowledge Article | Science & Tech. | 43.699105 |
Two trees 20 metres and 30 metres long, lean across a passageway between two vertical walls. They cross at a point 8 metres above the ground. What is the distance between the foot of the trees?
Three triangles ABC, CBD and ABD (where D is a point on AC) are all
isosceles. Find all the angles. Prove that the ratio of AB... | <urn:uuid:11da5587-7026-4229-8ba5-be33afdc8778> | 3.359375 | 344 | Tutorial | Science & Tech. | 62.938129 |
How many people died? It's one of the first questions asked in a war or violent conflict, but it's one of the hardest to answer. In the chaos of war many deaths go unrecorded and all sides have an interest in distorting the figures. The best we can do is come up with estimates, but the trouble is that different statist... | <urn:uuid:719c2e3b-2849-49ab-944d-ec8477d76b9f> | 2.921875 | 441 | Content Listing | Science & Tech. | 47.00393 |
It is exciting to see China enter the space race and for the
US to propose new ventures to the moon and Mars. Yet there
is a lack of vision behind human space projects which has
prevented sustained support and progress.
We have a motivating purpose behind a sustained drive into
space: the purpose of space research shou... | <urn:uuid:017942a4-705d-4a2b-aa04-76b12817240b> | 3.0625 | 682 | Personal Blog | Science & Tech. | 60.637775 |
Ask a question about 'Skid-to-turn'
Start a new discussion about 'Skid-to-turn'
Answer questions from other users
is an aeronautical vehicle reference for how such a vehicle may be turned. It applies to vehicles such as aircraft and missiles. In skid-to-turn, the vehicle does not roll to a preferred angle. Instead comm... | <urn:uuid:274bae68-a324-45d9-b77b-707e9c8ef865> | 3.625 | 317 | Q&A Forum | Science & Tech. | 41.277278 |
VARIATION IN DNA CONTENT AMONGST DIFFERENT SPECIES
afc at gnv.ifas.ufl.edu
Mon Jan 31 09:33:18 EST 1994
In article <1994Jan28.190047.6170 at iitmax.iit.edu>, garfinkl at iitmax.iit.edu (Mark D. Garfinkel) writes:
> afc at gnv.ifas.ufl.edu (Andrew Cockburn) writes:
> *The readers of this thread would do well to review B... | <urn:uuid:0b15f6a4-804e-4673-be8e-8cd63a708df1> | 2.703125 | 693 | Comment Section | Science & Tech. | 45.779586 |
User events such as a mouse click are received by the browser process, then marshaled to WebKit where the click event is hit tested through a page's DOM, checking for event handlers along the way. On touch-capable devices, a finger drag can be used to scroll the page, but a Touch event handler on the page may also opti... | <urn:uuid:bf2a969a-3cf5-48ea-847e-167e6dd1a09c> | 2.703125 | 1,148 | Documentation | Software Dev. | 33.719478 |
Bats of Ouray National Wildlife Refuge, Utah
Ouray National Wildlife Refuge (NWR) is located in the northeast corner of Utah along the Green River and is part of the Upper Colorado River System and the Colorado Plateau. The Colorado Plateau is home to 19 species of bats, some of which are quite rare. Of those 19 specie... | <urn:uuid:5fcca6f9-0332-4178-9272-a558664b9388> | 3.421875 | 270 | Knowledge Article | Science & Tech. | 45.19922 |
ANSI Common Lisp 24 System Construction 24.1 System Construction Concepts
To load a file is to treat its contents as code
and execute that code.
The file may contain source code or compiled code.
A file containing source code is called a source file.
Loading a source file is accomplished essentially
by sequentially rea... | <urn:uuid:aea92957-7a1f-40b5-ba10-6cace369d796> | 3.4375 | 178 | Documentation | Software Dev. | 42.5235 |
In this video segment, participants discuss some of the vocabulary of geometry. Watch this segment after you have completed Problems D1-D3 and compare your thinking with that of the onscreen participants.
What are some of the difficulties the participants ran into while trying to define a point and a line? How are your... | <urn:uuid:1ecb0712-ca13-4075-af6d-92b74682713f> | 3.3125 | 107 | Truncated | Science & Tech. | 44.263099 |
Wetland Changes Affect South Florida Freezes
Orange and other citrus crops are being squeezed by stronger freezes in South Florida, due to changes in wetlands.
Image to right: Landsat Satellite Looks at Florida -- This image mosaic of South Florida was acquired by the Landsat-5 satellite during the late-1980's. The lar... | <urn:uuid:3cda0754-58d9-4ffb-a5a5-43e561e7bb8a> | 3.71875 | 1,059 | Knowledge Article | Science & Tech. | 46.271548 |
Evolution and Structure of the Internet by Romualdo Pastor-Satorras and Alessandro Vespignani, Cambridge University Press, £40, ISBN 0521826985
GREATEST information resource ever? That has to be the internet. Lacking any central management, yet supremely efficient and dependable, this "network of networks" is also a ma... | <urn:uuid:0ed5bfe5-3371-4bc2-9686-cfc3473b1595> | 2.703125 | 188 | Truncated | Science & Tech. | 26.773542 |
Spider Pictures, Pictures of Arachnids, Facts, and Information
Pictures of spiders and other arachnids, including scorpions, with detailed information.
The arachnid family includes over 100,000 known species including spiders, scorpions, harvestmen, ticks, solifugae, and mites. Most of those species are terrestrial, bu... | <urn:uuid:bdb04956-45d2-4a7d-8f76-6fd2e7acbc06> | 3.1875 | 398 | Knowledge Article | Science & Tech. | 48.052206 |
When studying animal behaviors, biologists generally have to wait for something to happen — either for an animal to do something, or for one animal to provoke another. Alternatively, they could use robot animals, tempting them with sexy fembots, mama-bots or tasty prey.
Predators of the threatened Mojave ground squirre... | <urn:uuid:8534d993-11aa-4e3f-8379-67015f801540> | 2.71875 | 210 | Content Listing | Science & Tech. | 45.415094 |
Charles Kuen Kao (1933-)
Charles Kuen Kao is a pioneer in the development of fibre optics for use in telecommunications.
Kao was born in Shanghai in 1933. His father, a judge in the Court for International Law, had received an excellent education in both China and the United States. Kao was tutored at home with his bro... | <urn:uuid:a52163b8-f0a0-41f5-bfb5-c6f3eef60b58> | 2.703125 | 441 | Knowledge Article | Science & Tech. | 32.770562 |
Writing in this week's Science, University of Witwatersrand palaeontologist Professor Lyn Wadley and her colleagues describe an excavation they have carried out in a cave site called Sibudu in South Africa's KwaZulu Natal Province.
Dating from 77,000 years ago, the team have uncovered successive layers of sedge, and ot... | <urn:uuid:11884d03-d283-447c-922c-27fc2b6412b5> | 3.359375 | 505 | Comment Section | Science & Tech. | 53.897727 |
[Picture credit: Suvendra Dutta]
The closest void in our galactic neighborhood is called the 'local void'. It is empty except for a lonely dwarf galaxy whose velocity indicates it's trying to move out of the void. That behavior is what one would expect to happen to underdense regions during structure formation. Accordi... | <urn:uuid:00397da6-0ef9-4ef7-8a8b-bd959481b43c> | 2.859375 | 661 | Personal Blog | Science & Tech. | 49.919915 |
I know outside a nucleus, neutrons are unstable and they have half life of about 15 minutes. But when they are together with protons inside the nucleus, they are stable. How does that happen?
I got this from wikipedia:
When bound inside of a nucleus, the instability of a single neutron to beta decay is balanced against... | <urn:uuid:36cc5814-fbf1-41fb-b7b1-3209c5aa748c> | 3.625 | 202 | Q&A Forum | Science & Tech. | 49.053362 |
This recent map of sea-surface temperature anomalies shows that weak El Nino conditions have developed in the tropical Pacific.
Forecasts by the International Research Institute for Climate and Society and other institutions show that a weak El Niño has developed in the equatorial Pacific, and is likely to continue evo... | <urn:uuid:356de354-8503-46db-b329-f812cddce324> | 4.28125 | 1,826 | Knowledge Article | Science & Tech. | 32.271615 |
Date: 1993 - 1999
Where do asteroids come from?
I have looked in several astronomy texts, and they pretty much agree
that the asteroids are material that never quite got together to form a planet.
Many astronomers believe that the early solar system was a swirling cloud of
dust and gas. Sometimes particles of dust woul... | <urn:uuid:7f9b2606-565b-4bf1-9048-1be7b3f891d7> | 4.125 | 233 | Knowledge Article | Science & Tech. | 37.864733 |
There are examples all around us of using Perl for code generation:
- CGI: Perl is probably the number one tool used in generating HTML code for CGI.
- SQL: Perl is often used to generate SQL code for database interaction.
- The B::.... modules (need I say more?).
- eval (it's mere existance....)
Those are just some ve... | <urn:uuid:8cc261d6-1c5b-43d9-865b-8595563bf795> | 2.90625 | 438 | Content Listing | Software Dev. | 73.372328 |
- Purpose: Show that an object's acceleration, under the influence
of gravity, is un-effected by the objects velocity.
- Cock mechanism; place pin in hole to keep cocked; place balls
on ends; release pin to eject balls.
- One ball drops vertically, with zero initial velocity; other
ball launched horizontally. Balls hit... | <urn:uuid:a10333f1-efb0-4764-8f03-ed3a5682eb8f> | 3.140625 | 86 | Content Listing | Science & Tech. | 38.962328 |
Wave on Circular Loop
- This demonstration has been used to explain how sound can
be used to break a wine glass, or to help illustrate principles behind the
Bohr model of the hydrogen atom.
- There are two configurations of loops from which to choose:
parallel to the floor or perpendicular to the floor.
- When changing... | <urn:uuid:2a36e45e-25e6-4d31-b3e9-eb5ef08d8281> | 3.5 | 122 | Tutorial | Science & Tech. | 30.180194 |
by Staff Writers
Manoa HI (SPX) Aug 31, 2011
Since the beginning of the Industrial Revolution, the concentration of carbon dioxide in the atmosphere has been rising due to the burning of fossil fuels. Increased absorption of this carbon by the oceans is lowering the seawater pH (the scale which measures how acidic or b... | <urn:uuid:393d6671-3dd4-4def-9bb3-c4af63315966> | 3.09375 | 758 | Truncated | Science & Tech. | 26.82656 |
Similar organisms generally have similar genome sizes. Given this, would two species of yeast have the same number of genes and chromosomes?
Edit: Fixed with thanks to @daniel-standage
This question appears to start from the premise that different species of yeast are closely related, but they aren't. Saccharomyces cer... | <urn:uuid:a29d6672-a66f-471e-911f-050b7367ba55> | 3.15625 | 235 | Q&A Forum | Science & Tech. | 48.606333 |
Terabyte online databases, consisting of billions of records, are becoming common as the price of online storage decreases. These databases are often represented and manipulated using the SQL relational model. A relational database consists of relations (files in COBOL terminology) that in turn contain tuples (records ... | <urn:uuid:a1d6e4be-8b7f-4d6e-81f9-c8c5a07dc2c0> | 3.34375 | 1,001 | Knowledge Article | Software Dev. | 26.189338 |
We know that the sun's output can vary by about 1 Watt per square meter during a solar cycle. So try computing the temperature with 1368 instead of 1367. Try again with 1366. How much difference does that make? I get about 0.05 K (0.09 F). That's a pretty small number. We'd be hard-pressed to get a thermometer to recor... | <urn:uuid:2bd84287-7cb9-4f2e-90e6-a711b6f59166> | 3.875 | 1,112 | Personal Blog | Science & Tech. | 68.997707 |
The Perciformes is the largest order of vertebrates and includes around 40% of all bony fish. Their name means perch-like. They are ray-finned fish and have over 7000 different species. There are many different sizes and colors, and they are found in fresh and marine enviroments. The first documented species appeared i... | <urn:uuid:517822ef-9ee6-4e21-9010-b8462e6b7565> | 3.546875 | 193 | Knowledge Article | Science & Tech. | 40.792599 |
Major Section: PROGRAMMING
(= x y) is logically equivalent to
(equal x y).
= has a guard requiring both of its arguments
to be numbers. Generally,
= is executed more efficiently than
For a discussion of the various ways to test against 0, See zero-test-idioms.
= is a Common Lisp function. See any Common Lisp documentat... | <urn:uuid:06608cd9-dc8a-456a-b9e7-bb626ac99b71> | 2.953125 | 85 | Documentation | Software Dev. | 49.811368 |
Scientific Investigations Report 2012–5187
Groundwater is essential for water supply and plays a critical role in maintaining the environmental health of freshwater and estuarine ecosystems in the Atlantic Coastal basins of New Jersey. The unconfined Kirkwood-Cohansey aquifer system and the confined Atlantic City 800-f... | <urn:uuid:f5dcb04d-a6e2-438d-a73a-cac1b2c43a70> | 2.78125 | 1,547 | Academic Writing | Science & Tech. | 32.018995 |
Ever wondered what exotic life forms may be lurking in the dark, hidden corners of your home? Scientists wonder too. Studies have shown that our modern plumbing systems provide sanctuary to a menagerie of microbes. A new pilot project plans to elicit the help of homeowners to catalogue the life growing in their water h... | <urn:uuid:597fd5c8-e3d1-4f6b-b277-62e96c88a5f0> | 3.171875 | 226 | Truncated | Science & Tech. | 45.099274 |
By Seth Borenstein – It’s one thing to make an object invisible, like Harry Potter’s mythical cloak. But scientists have made an entire event impossible to see. They have invented a time masker.
The scientists created a lens of not just light, but time. Their method splits light, speeding up one part of light and slowi... | <urn:uuid:888837af-2a2f-48fc-a15b-4bed8cc25aef> | 3.09375 | 303 | Truncated | Science & Tech. | 65.616029 |
The Solar Maximum Mission (SMM) spacecraft was launched on February 14, 1980, near the height of the solar cycle, to enable the solar phsyics community to examine, in more physically meaningful detail than ever before, the most violent aspect of solar activity: flares.SMM recorded its final data in November, 1989.
(Fro... | <urn:uuid:6fd6aee6-ba74-4423-ae2a-5a82eaf48246> | 3.15625 | 156 | Knowledge Article | Science & Tech. | 63.051429 |
Unsolved problems in mathematics
From Uncyclopedia, the content-free encyclopedia
| Unsolved Problems|
This article is part of Uncyclopedia's unsolved problems in … series.
|Unsolved problems in …|
Unsolved mathematical problems are those which have either exceeded the intellect of every living mathematician so far in ... | <urn:uuid:398d270b-1d3a-4b67-9fff-be2acbfb3276> | 2.90625 | 1,140 | Content Listing | Science & Tech. | 52.762776 |