text large_stringlengths 148 17k | id large_stringlengths 47 47 | score float64 2.69 5.31 | tokens int64 36 7.79k | format large_stringclasses 13
values | topic large_stringclasses 2
values | fr_ease float64 20 157 |
|---|---|---|---|---|---|---|
A car of mass 1.5 tonnes pass over a bridge formed the arc of a circle of radius 20m.
a) Find the force exerted by the car on the road at the top of the bridge if the car is travelling at 10m/s.
b) What speed would cause the car to be on the point of lifting up off the bridge at its highest point
What I've done:
F = mv... | <urn:uuid:f40bcc9f-e755-4396-9e7c-29650ddb9f00> | 2.828125 | 257 | Q&A Forum | Science & Tech. | 122.214382 |
Rationalizing Maxwell's Equations
Maxwell's equations in Gaussian units are shown at the right. Gaussian units are based on the cgs system of mechanical units, and were long dominant for theoretical investigations. Absolute electrostatic units (esu) are used for electrical quantities, absolute electromagnetic units (em... | <urn:uuid:6d9b9a3b-7674-4194-ac02-f974b8015b00> | 3.640625 | 1,515 | Academic Writing | Science & Tech. | 71.204025 |
ABSTRACT. One hundred years ago we did not know how stars generate energy, the age of the Universe was thought to be only millions of years, and our Milky Way galaxy was the only galaxy known. Today, we know that we live in an evolving and expanding Universe comprising billions of galaxies, all held together by dark ma... | <urn:uuid:f1931f08-c6a4-4e0d-9295-81002f26847a> | 3.375 | 251 | Academic Writing | Science & Tech. | 30.978169 |
A new generation of robotic explorers are going to search for water on Mars.
The rover is a mobile geology lab
Mark Adler, deputy manager on the US space agency (Nasa) mission, talks to BBC News Online's Helen Briggs about what they might encounter.
HB: How does each rover work?
MA: It's a solar powered robot. At about... | <urn:uuid:8287d1bd-8218-43bb-80f2-2799a114a967> | 3.640625 | 621 | Audio Transcript | Science & Tech. | 60.433342 |
Google Coding Conventions
Only deviations from the Google style guide will be documented here.
We use JsDoc comments as outlined in the Google style guide with but we name the variable name directly after the @param tag and the type without curly braces.
Generally we encourage inline comments. These help readers of you... | <urn:uuid:c36995a3-4761-477f-a692-61036530c058> | 2.90625 | 334 | Documentation | Software Dev. | 25.023897 |
Astronomers have just released the highest-resolution images ever taken of the Sun's corona, or million-degree outer atmosphere, in an extreme-ultraviolet wavelength of light. The 16-megapixel images were captured by NASA's High Resolution Coronal Imager, or Hi-C. The Hi-C telescope provides five times more detail than... | <urn:uuid:dd404fe6-93c0-4fe5-a6db-a5c8eae3a56e> | 2.9375 | 255 | Content Listing | Science & Tech. | 50.592433 |
What are Ice Jams?
Spring is the time of year when ice-covered rivers begin to thaw. As this ice breaks up into chunks, they move downstream and can jam in areas where the water flow bends, near bridges and abutments or in shallow areas. The restricted ice can then act as a dam, causing water to back up behind it. Rive... | <urn:uuid:10e9a76d-4887-4cf7-9eba-37575261c846> | 3.421875 | 270 | Comment Section | Science & Tech. | 59.574167 |
Attaching a short DNA molecule to two metal electrodes, researchers in the Netherlands have found evidence that DNA acts as a semiconductor for electrical charge. The figure shows the electrodes as two gray cliffs on either side of a chasm. In the experiment, the electrodes were separated by just 8 nanometers (billiont... | <urn:uuid:b6518aef-a91f-4d9b-bb2c-3e7376edbc0a> | 3.609375 | 399 | Knowledge Article | Science & Tech. | 37.207235 |
Sometimes both heaven and Earth erupt.
Colorful aurorae erupted unexpectedly earlier this month, with
green aurora appearing near the horizon and brilliant bands of
red aurora blooming high overhead.
A bright Moon lit the foreground of this picturesque scene,
while familiar stars could be seen far in the distance.
With... | <urn:uuid:d930dc1d-b461-4e13-b8a2-95623013e3d9> | 2.9375 | 208 | Knowledge Article | Science & Tech. | 35.465302 |
Python's Apache interpreter is available as an Apache module, mod_python. This module reduces the time it takes to deliver a given page to a client. It is also capable of a great deal more, including interacting with Apache itself in various powerful ways. This article gives you just a taste of what mod_python can do.
... | <urn:uuid:929f79dd-70ae-4379-87a9-d9baea47a6ad> | 2.78125 | 846 | Documentation | Software Dev. | 59.132344 |
How do you compute the volume of a cat?
Dunking it in water doesn’t work– you only get the volume of the rat-like creature that lives inside the cat; much like the feeble alien within a Dalek. (And, if your answer had anything to do with contour integrals, get real.)
Here is a low-tech method that works: Using successi... | <urn:uuid:6ec954bc-07f1-4cae-8b71-9ba4512a0b9d> | 2.8125 | 151 | Tutorial | Science & Tech. | 53.522858 |
and Without Sex
this glass water tank there are living organisms that may look like
plants but they are animals that can be found in tide pools along
the California coast. Many of these species spend their lives stuck
to rocks or separated from potential mates, and have developed unique
strategies to reproduce. Some re... | <urn:uuid:6d3e3167-a7f5-47f5-8a87-9e2dc2038f59> | 2.984375 | 95 | Knowledge Article | Science & Tech. | 28.596208 |
An example for both is the ArrayList class. It functions like an array (and is actually implemented using one), but provides precise control over where in the array you can access.
ArrayList<String> myList = new ArrayList<String>();
myList.add("hello"); // somehow the string "hello" gets added to the ArrayList
System.o... | <urn:uuid:0eae18ce-1060-4aad-8768-94ea775813a2> | 3.1875 | 168 | Comment Section | Software Dev. | 53.669672 |
Zebra Mussel Watch
The zebra mussel, a black-and-white striped bivalve mollusk, came to North American waters from Europe in international shipping ballast water. Since first discovered in Lake St. Clair in June 1988, the zebra mussel has spread rapidly throughout the Great Lakes and the Arkansas, Cumberland, Hudson, I... | <urn:uuid:537e8be1-8444-49f2-af9c-41e0be447956> | 3.65625 | 364 | Knowledge Article | Science & Tech. | 43.837623 |
The job of the manifest file is to indicate to the device the name and version of the MIDlet suite in the JAR and to specify which of the class files it contains correspond to the individual MIDlets. In order to make use of this information, however, the device must download the JAR and extract the manifest. Having don... | <urn:uuid:b9a76481-8a13-47fc-aa92-fab47a77d9d2> | 3 | 1,791 | Documentation | Software Dev. | 46.878217 |
Search our database of handpicked sites
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.
You searched for
We found 3 results on physics.org and 15 results in our database of sites
15 are Websites,
0 are Videos,
and 0 ... | <urn:uuid:3a120911-02cc-408c-83a5-3758962cbce6> | 3.21875 | 299 | Content Listing | Science & Tech. | 51.18354 |
Photograph by Evan Hurd/Getty Images
2001: The Institute for Genomic Research, founded by Venter, helps sequence the genome of the anthrax strain mailed in the attacks that killed five people evidence that eventually leads the FBI to the source.
2004: Sorcerer II, Venters 95-foot sailboat, leaves Halifax, Nova Scotia, ... | <urn:uuid:d3d15d1b-1c5a-401f-947f-5cc07c56f232> | 2.921875 | 309 | Listicle | Science & Tech. | 38.142204 |
Atomic radius (empirical)
These values derived by J.C. Slater are an empirical set of atomic radii derived by the careful comparison of bond lengths in over 1200 bond types in ionic, metallic, and covalent crystals and molecules (reference 1).
The idea is that for a bond A-B, the atomic radius of A added to the atomic ... | <urn:uuid:9d02d049-b5b7-40dc-8cde-82d281985b6f> | 3.125 | 183 | Knowledge Article | Science & Tech. | 38.781034 |
Building Resilience in a Changing Climate
What is Adaptation?
Lying to the young is wrong.
Proving to them that lies are true is wrong.
that God's in his heaven
and all's well with the world
They know what you mean.
They are people too.
Tell them the difficulties
can't be counted,
and let them see
what will be
these pr... | <urn:uuid:449c3f5c-99a9-4f08-981d-186d697c7bb3> | 3.390625 | 2,089 | Academic Writing | Science & Tech. | 34.798363 |
A Brief History of Time
We've always talked about our hardware upgrades and how well they perform. Our hardware architecture is, no doubt, critical to the success of the site, but the software that actually runs AnandTech.com is equally important. Recently, we performed a major architecture shift from a ColdFusion base... | <urn:uuid:35151954-dc9e-4b9c-a546-5b61194508a5> | 2.75 | 563 | Truncated | Software Dev. | 49.509403 |
Jellyfish Rule! --- Moon Jellyfish [LiveScience 2011-04-28]
The moon jellyfish is believed to have been introduced into many new environments by ships, when the jellyfish's stationary developmental stage, called a polyp, attached to their hulls or came in via the ballast water, which ships dump once they arrive at thei... | <urn:uuid:da2ba035-7894-47e2-8d8c-0593cd2b550a> | 3.5 | 431 | Knowledge Article | Science & Tech. | 23.993445 |
Needs Summary: This article does not have a summary. Summaries give a brief overview of the topic and are automatically included on some listing pages that link to this article.
The width property is a standard HTML attribute. The value of this attribute is usually an integer.
It is very common to see HTML tags like im... | <urn:uuid:f95faae6-a2e8-40d5-ac3f-78aa48441da2> | 2.90625 | 196 | Documentation | Software Dev. | 44.776088 |
About Recombinant DNA
Recombinant DNA is the technology that allows us to insert genes from one organism into another to make it produce a protein product, copy the gene multiple times, or give it a new trait. The discovery of recombinant DNA was considered the "birth" of modern biotechnology.
Deoxyribonucleic acid, or... | <urn:uuid:072d0a61-3367-45ea-a61e-a5a34ee248dc> | 4.0625 | 1,848 | Knowledge Article | Science & Tech. | 54.24249 |
Quasars have remained enigmatic ever since their discovery in 1963 because of the way they emit prodigious amounts of energy yet are very compact. Their star-like appearance gave birth to the name quasi-stellar object, later shortened 'to 'quasar'. The most widely accepted theory to explain quasars is that they are pow... | <urn:uuid:6567fe32-da36-4956-9b93-92989fbf4593> | 4.21875 | 165 | Knowledge Article | Science & Tech. | 43.85093 |
[Tkinter-discuss] How can I edit a string inside a textbox?
fredrik at pythonware.com
Thu Dec 6 12:27:17 CET 2007
Alex Garipidis wrote:
> I have a Tkinter Textbox in my application. I want to scan the
> textbox for a symbol, defined by me as a "mark", and
> change the word that is inside or next to that symbol.
> This ... | <urn:uuid:5c4dde72-9d2a-438a-ab33-c9531776dd57> | 2.9375 | 459 | Comment Section | Software Dev. | 78.164567 |
Hi guys, i need help with this problem that i seriously have no idea with.
with t=0 representing the year 1990.
1. What is the population of elk in the year 2004
2. Determine the years between 1990 and 2020 in which the elk population is at its maximum
3 Explain the period of the function in context of the problem
4 Gr... | <urn:uuid:9560a553-2f06-434f-b5d8-8cfb543c4a99> | 2.6875 | 104 | Q&A Forum | Science & Tech. | 86.124397 |
What does potential at a point exactly mean? My teacher tells me that current flows from higher potential to lower potential but when I ask him the reason, he fails to give me a convincing answer.
And can anyone explain how electric potential is related to potential energy & work done?
Further, when I referred a Physic... | <urn:uuid:75b4b29a-54ac-4154-84a6-8edadcee8eb4> | 3.03125 | 275 | Q&A Forum | Science & Tech. | 40.369829 |
Can any one please explain this piece of code I found in the linux kernel source. I see a lots of code like this in linux and minix kernel but dont seem to find what it does (even if C compilers ...
On the Wikipedia page for Windows, it states the Windows is written in Assembly for the bootloader and task switcher, and... | <urn:uuid:dc1a1f4d-6734-4a34-8bf4-ea788b4ccacf> | 2.703125 | 219 | Q&A Forum | Software Dev. | 70.764685 |
This is one of my favorite things about ants -- the ant death spiral. Actually, it's a circular mill, first described in army ants by Schneirla (1944). A circle of army ants, each one following the ant in front, becomes locked into a circular mill. They will continue to circle each other until they all die. How crazy i... | <urn:uuid:cf6553e2-7741-4022-9a3e-aa2bedcd016e> | 2.6875 | 472 | Personal Blog | Science & Tech. | 60.387434 |
Science Fair Project Encyclopedia
The name is derived from the Greek words kopros meaning "dung" and lithos meaning "stone".
Coprolites are also trace fossils and vary in size from the small fecal pellets of a sea-snail to the large droppings of crocodiles, dinosaurs, or mammals. Typical sizes vary from less than 5 mm ... | <urn:uuid:757d82d3-76ea-4463-acd7-d0a002736e94> | 3.875 | 378 | Knowledge Article | Science & Tech. | 36.343097 |
Pliocene Climate Lessons
An ongoing reconstruction of a warmer Earth 3 million years ago helps test climate-change forecasts
The middle portion of the Pliocene Epoch—about three million years ago—is the most recent period when global temperatures were sustained at levels comparable to those we may see at the end of thi... | <urn:uuid:8fee3722-7c1a-48be-96fe-979ae6a2db57> | 3.484375 | 129 | Truncated | Science & Tech. | 24.595 |
Simply begin typing or use the editing tools above to add to this article.
Once you are finished and click submit, your modifications will be sent to our editors for review.
...poses environmental challenges, especially in regions where it occurs. Even so, oil shales and tar sands are abundant, and advances in recovery... | <urn:uuid:f5f459dd-7280-4a04-b08c-4935b655d985> | 2.875 | 231 | Truncated | Science & Tech. | 28.548333 |
Understanding the relative importance of these two factors is key to designing effective conservation strategies. It may be common sense to focus on boosting numbers if demographics matter more, and to put together breeding programmes that expand the remaining gene pool if genetics rule, but accurately pointing the fin... | <urn:uuid:dee41189-7556-48fd-96d1-82e77dddea00> | 3.734375 | 609 | Knowledge Article | Science & Tech. | 35.216859 |
Definitions for absorption, electric
The Standard Electrical Dictionary
A property of the static charge. When a Leyden jar is being charged it dilates a little and the capacity increases, so that it can take a little more charge for a given potential difference existing between its two coatings. This phenomenon occurs ... | <urn:uuid:1f67f55a-2156-4fad-9c4d-fda3a88e8594> | 2.875 | 195 | Structured Data | Science & Tech. | 43.155256 |
Another Newbie question :)
Keith.Wansbrough at cl.cam.ac.uk
Wed Nov 5 12:27:35 EST 2003
> I seem to understand the basic idea behind the fold function, i think but do
> not seem to be able to write them myself. My understanding is that it works
> by replacing every constructor with a fold ?
I think you mean "replaces e... | <urn:uuid:a1a4af3a-9e0e-4c13-b7d0-3b250c368ad2> | 3.578125 | 532 | Comment Section | Software Dev. | 86.086212 |
Mishka Henner, Astronomical, twelve 506 paged volumes of black pages with planets and the sun on 11 of the pages. The Solar System is mostly pretty empty.
Top: Jupiter on page 283 of volume 2
Bottom: The Earth on page 155 of volume 1
Each page = 1,000,000 km. A picture of each planet in the Solar System is on a page eq... | <urn:uuid:6d7115ab-d4be-408f-8fde-4bca9c8a1794> | 2.84375 | 229 | Personal Blog | Science & Tech. | 73.415 |
"In a stunning first for neuroscience, researchers have created an electronic link between the brains of two rats, and demonstrated that signals from the mind of one can help the second solve basic puzzles in real time — even when those animals are separated by thousands of miles."
posted by sarastro
on Feb 28, 2013 -
... | <urn:uuid:5cbf8340-66b8-4364-b856-1f978ded162d> | 3 | 1,400 | Comment Section | Science & Tech. | 37.661744 |
strand synthesis uses a single, dimeric DNAPol III enzyme
Models of DNA synthesis often show it as occurring independently on the leading and lagging strands, with separate DNAPol IIIs on each. However, replication at any one fork is under the control of a single, dimeric DNAPol III holoenzyme [the two donut-shaped rin... | <urn:uuid:c4d1c467-88a2-4e0a-9bca-7ab1daae6899> | 3.09375 | 268 | Knowledge Article | Science & Tech. | 30.715909 |
AERIAL land photographs are vital for hundreds of scientific, commercial and military projects. Now similar panoramas of the seafloor may be possible, thanks to a scanning laser system described at a conference last week. Such images "would radically change the way we now think about and work in the submarine environme... | <urn:uuid:ae51b7b1-b7c9-4a17-8ab1-cf6dfd363c78> | 3.609375 | 215 | Truncated | Science & Tech. | 36.203732 |
In America, the kind Nycticeius gathers two species of Chauve-souris of the family of the Vespertilionidae;
- Nycticeius humeralis (Rafinesque, 1818) - evening bat
- Nycticeius cubanus (Cuban Evening Beats) - evening bat of Cuba.
DescriptionThe evening bat is a small brown bat weighing 7 to 15 grams.
DistributionOne fi... | <urn:uuid:507a1cb1-d63d-4e51-a30a-3ede89cc95f0> | 3.0625 | 548 | Knowledge Article | Science & Tech. | 38.492733 |
Texas 80-Meter Wind Map and Wind Resource Potential
The U.S. Department of Energy's Wind Program and the National Renewable Energy Laboratory (NREL) published an 80-meter (m) height wind resource map for Texas. This map is a key piece of understanding the state's wind resource potential from a development, policy, and ... | <urn:uuid:df1fdb11-861a-47b0-9e08-7568602603c1> | 2.96875 | 510 | Knowledge Article | Science & Tech. | 35.463571 |
Triton is the largest moon of Neptune, with a diameter of 2,700 kilometers. It was discovered by William Lassell, a British astronomer, in 1846 scarcely a month after Neptune was discovered.
Triton is colder than any other measured object in the Solar System with a surface temperature of -235 C (-391 F). It has an extr... | <urn:uuid:67fcc7b8-a6c2-4813-a296-2775ab1c4f8b> | 4.34375 | 313 | Knowledge Article | Science & Tech. | 41.1676 |
Bats of the genus Pteronotus (Chiroptera: Mormoopidae) are known to inhabit high-temperature roosts. This study examines the thermal ecology of a colony of three different species of Pteronotus in a sea cave on the Osa Peninsula of Costa Rica. Previous work found the cave to be inhabited by three species of the same ge... | <urn:uuid:aec61249-6e34-42f1-99e3-caa3b20778fb> | 3.578125 | 480 | Academic Writing | Science & Tech. | 29.588175 |
We work in three dimensions, with similar definitions holding in any other number of dimensions. In three dimensions, a form of the type
is called a differential form. This form is called exact on a domain in space if there exists some scalar function defined on such that
throughout D. This is equivalent to saying that... | <urn:uuid:c4854a7e-2324-4c87-a9d0-633a89def7f1> | 3.4375 | 842 | Knowledge Article | Science & Tech. | 43.51895 |
From optical and infrared galaxy surveys we know that the distribution of visible mass in the local Universe is far from uniform. Over the characteristic distance of 100 Mpc the number density of galaxies in galaxy superclusters and voids may vary by an order of magnitude. Some huge mass agglomerations (M>1015 Msun) in... | <urn:uuid:34664a4b-6143-4fce-ad44-8ff4119520d9> | 2.703125 | 429 | Knowledge Article | Science & Tech. | 34.169832 |
Triangles, Sines, and Areas
Library Home || Primary || Math Fundamentals || Pre-Algebra ||
Algebra || Geometry || Discrete Math || Trig/Calc
|Trig/Calc, difficulty level 3. Show that the area of any triangle is .5*b*c*sin(A).|
|Please Note: Use of the following materials requires membership. Please see the Problem of t... | <urn:uuid:434a55cc-2950-4157-850f-5d34ef7a3445> | 3.1875 | 133 | Content Listing | Science & Tech. | 43.675166 |
William Thomson called them “beautiful and ingenious geometrical constructions,” and in variance to their rather humdrum name dygograms are certainly charming to the eye. But these geometric constructions can conveniently generate and then calculate the magnetic deviation of a ship compass at a location.
With our elect... | <urn:uuid:865aadf3-296d-4cb0-a3cf-7a2a2dfa05bd> | 3.46875 | 665 | Content Listing | Science & Tech. | 23.284208 |
The MK Spectral classification system was founded by W.W. Morgan and P.C. Keenan in the year 1943, with the publication of the first photographic spectral classification atlas, An Atlas of Stellar Spectra (Morgan, Keenan & Kellman 1943). Since that time, the MK system has been extensively revised and refined by Morgan,... | <urn:uuid:1e8a7187-3451-4aa7-9e9c-807537677a2d> | 3.140625 | 918 | Knowledge Article | Science & Tech. | 44.45205 |
What does logic mean to us and is that different to mathematical logic? We will explore these questions in this article.
Learn about the link between logical arguments and electronic circuits. Investigate the logical connectives by making and testing your own circuits and fill in the blanks in truth tables to record. .... | <urn:uuid:829674cb-8121-46bf-837a-9f1863e28df3> | 3 | 118 | Tutorial | Science & Tech. | 50.808068 |
I understand that a water heater element is basically just adding energy to the mass of water in the container. So does that mean that the heater element only has to keep adding energy while the water around it becomes hotter than the element itself? Or does the element warm up together with the water until both reach ... | <urn:uuid:1913283c-20b6-4ad9-945e-e25bfea13d91> | 2.96875 | 210 | Q&A Forum | Science & Tech. | 50.746909 |
Reader Scott writes in with a good question that I’ve heard posed by several people in various places, because it really goes to the core of the counterintuitive nature of relativity.
Okay, let’s assume I’m in a spacecraft moving at a speed of c-1 m/s. That’s one m/s less than the speed of light. Would I be able to mov... | <urn:uuid:164f798c-469f-4e77-a27b-b78b7d5bbca4> | 2.734375 | 551 | Personal Blog | Science & Tech. | 70.235802 |
Creating and Modifying FOREIGN KEY Constraints
You can create a FOREIGN KEY constraint as part of the table definition when you create a table. If a table already exists, you can add a FOREIGN KEY constraint, provided that the FOREIGN KEY constraint is linked to an existing PRIMARY KEY constraints or UNIQUE constraint ... | <urn:uuid:c4121b30-4f0e-4abf-8575-540f94fabe17> | 2.75 | 716 | Documentation | Software Dev. | 27.52833 |
Ask a question about 'Undecane'
Start a new discussion about 'Undecane'
Answer questions from other users
is a liquid alkane
Alkanes are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds without any cycles...
In organic chemistry, a hydrocarbon is an organic co... | <urn:uuid:71012352-4172-4513-af7b-af6801c1e257> | 3.21875 | 453 | Q&A Forum | Science & Tech. | 35.626546 |
Summary: Twenty-five years ago, NASA made its only visit thus far to the planet Uranus. Voyager 2 returned unexpected images of an active planet and moons with dramatic surface features. The visit expanded our knowledge of the planets and helped astrobiologists understand whether or not planets and moons in the outer S... | <urn:uuid:ead4d981-ba86-44ee-bd2b-d40ae2d4b0e7> | 3.84375 | 1,026 | Knowledge Article | Science & Tech. | 43.656405 |
genecutl at mendel.berkeley.edu
Sat Feb 26 13:45:06 EST 1994
In article <1994Feb26.164754.16156 at nessie.mcc.ac.uk>,
se040 at sna.co.umist.ac.uk (Mark Joseph Johnston) wrote:
> I am a computer science student working on genetic algorithms and want to ask
> a "silly" question.
> Recessive genes are generally not "good"... | <urn:uuid:6f392dae-832f-4ea1-953c-109442eecace> | 2.8125 | 328 | Comment Section | Science & Tech. | 48.528285 |
Click image for description
| Orbital characteristics (Epoch J2000)
| Semi-major axis
|| 1,426,725,413 km|
9.537 070 32 AU
| Orbital circumference
|| 8.958 Tm|
|| 0.054 150 60
|| 1,349,467,375 km|
9.020 632 24 AU
|| 1,503,983,449 km|
10.053 508 40 AU
| Orbital period
|| 10,757.7365 d|
| Synodic period
|| 378.09 d
| Avg... | <urn:uuid:0287aac4-5a38-46f0-953f-e098d27e52f9> | 3.234375 | 3,387 | Knowledge Article | Science & Tech. | 58.382442 |
Common Lisp the Language, 2nd Edition
The function make-condition is the basic means for creating condition objects.
make-condition type &rest slot-initializations
Constructs a condition object of the given type using slot-initializations as a specification of the initial value of the slots. The newly created condition... | <urn:uuid:98c2f656-b85d-43a5-90a8-5074fc28498f> | 3 | 109 | Documentation | Software Dev. | 22.89 |
by Gerald Newton
November 5, 1999
The geometric addition of vectors gives a fast approximation of neutral current in a three phase system. A more precise calculation can be performed using algebra. This can be a long mathematical problem, but by restricting our calculation to A phase at 0 degrees, B phase at 120 degree... | <urn:uuid:127adf77-3e5b-49ca-815d-12f90423a869> | 3.6875 | 314 | Tutorial | Science & Tech. | 53.393998 |
Reverse transcriptase is an enzyme used by all retroviruses that transcribes the genetic information from the virus from RNA into DNA, which can integrate into the host genome. Usually, transcription only runs from DNA to RNA, catalyzed by RNA polymerase. An example of this kind of enzyme is the reverse transcriptase f... | <urn:uuid:9ddd06ce-6f40-4b11-be05-06d1ed44d103> | 3.9375 | 176 | Knowledge Article | Science & Tech. | 39.893889 |
This is Chapter 8 of the Arctic Climate Impact Assessment
Lead Authors: Frederick J.Wrona,Terry D. Prowse, James D. Reist; Contributing Authors: Richard Beamish, John J. Gibson, John Hobbie, Erik Jeppesen, Jackie King, Guenter Koeck, Atte Korhola, Lucie Lévesque, Robie Macdonald, Michael Power,Vladimir Skvortsov,Warwic... | <urn:uuid:8a57889c-6cf5-4de2-9308-7e23cc072074> | 2.890625 | 791 | Knowledge Article | Science & Tech. | 38.407642 |
July 26, 2009
Analysis of Alarmism: Ocean Acidification
“Only the unknown frightens men.” Antoine de St. Exupery
Scare Tactics To Create Fear
As public awareness grows that human caused warming is false, the extent and degree of attempts to scare the public increases. The scare preference is for remote geographic areas... | <urn:uuid:8e207e3e-96b3-4122-986b-8961993e1b9f> | 2.84375 | 1,616 | Nonfiction Writing | Science & Tech. | 44.774863 |
Some things you really can pin on climate change – the heatwave that struck Texas last year, for instance. A long-term rise in temperatures due to greenhouse gas emissions made the hot weather 20 times more likely, modelling suggests.
The same study found that four other extreme weather events last year can be linked t... | <urn:uuid:513a3317-b8c1-4e14-9ab4-a427ae81e908> | 3.84375 | 1,901 | Comment Section | Science & Tech. | 56.686333 |
refers to any of a number of loosely related concepts in different areas of geometry. Intuitively, curvature is the amount by which a geometric object deviates from being flat,
but this is defined in different ways depending on the context. There is a key distinction between extrinsic curvature
, which is defined for o... | <urn:uuid:50dc4b5a-dd95-4caa-9a7a-3d87e98cade8> | 4 | 939 | Knowledge Article | Science & Tech. | 34.517604 |
Just about anything that substantially affects climate change science or policy inevitably affects communication on those issues. The Yale Forum focus in this feature, and the major criterion for inclusion in notable climate developments of 2010, is on key climate happenings influencing public understanding of the subj... | <urn:uuid:f00339fd-f930-470c-ae5a-a5f1594a8fd5> | 3.265625 | 2,538 | Knowledge Article | Science & Tech. | 26.751721 |
Quantum computation is the current high visibility fad in atomic physics. These computers operate along the same lines as normal computers but every quantum bit (qubit) is both a one and zero at the same time. Only when the final result is desired do we measure the qubit state and receive either a one or a zero. The ma... | <urn:uuid:4b58168e-257a-46d4-8929-4bb7c02b2bee> | 3.4375 | 487 | Nonfiction Writing | Science & Tech. | 32.421667 |
What are These Chytrids?
Barr (1) delineated the order Spizellomycetales from the Chytridiales based on distinctive zoospore ultrastructure. Rhizophlyctis rosea was included in this new order, but recent ultrastructural and molecular analyses demonstrate that R. rosea is a morphogenus distinct from the Spizellomycetale... | <urn:uuid:1f3f8030-c85e-442a-a681-42f2c41d893d> | 3.359375 | 318 | Knowledge Article | Science & Tech. | 41.393618 |
Weather, temperature, carbon, water, soil and all other kinds of climate related open data. Including (but not limited to) data about:
- the atmosphere
- the weather
- air quality
- the ocean
- water levels
- water quality
- carbon emissions
- soil erosion
Existing Lists of Climate Datasets to Migrate Here
13 datasets ... | <urn:uuid:e1cff353-1262-4181-9e55-d3e49ad1ce8b> | 2.921875 | 537 | Content Listing | Science & Tech. | 34.115431 |
Here is a general implementation. It uses a templatized class, therefore it will get the combinations of any type of variable, not just characters.
The program takes advantage of the next_permutation algorithm and uses a set of bits to determine what to output. The way it works is that you call the NextCombination() fu... | <urn:uuid:dc5c0885-5473-42c3-b1bb-f23c8a55067a> | 3.28125 | 1,192 | Comment Section | Software Dev. | 70.281377 |
Working with controls. Using
Properties, Methods and Events
You use controls to
get user input and to display output. Some of the controls you can use
in your applications include text boxes, command buttons, and list
boxes. Other controls let you access other applications and process
data as if the remote application ... | <urn:uuid:4bd3b641-616f-4cb4-a31b-38060c16cdf3> | 3.90625 | 648 | Documentation | Software Dev. | 64.592271 |
3.5. Debugging sed scripts
The following two debuggers should make it easier to understand how
sed scripts operate. They can save hours of grief when trying to
determine the problems with a sed script.
(1) sd (sed debugger), by Brian Hiles
This debugger runs under a Unix shell, is powerful, and is easy to
use. sd has c... | <urn:uuid:8c02cbed-2388-4c34-a970-2d6ce91602d2> | 2.8125 | 230 | Tutorial | Software Dev. | 58.854429 |
Solar still built into a pit in the
through the use of a pit (or 'solar still') is a much touted
1) Clear plastic sheet for cooling condensate.
2) Sheet anchor stones (in a shallow ditch).
3) Condensate runs along sheet to drip into can.
4) Collection can, at bottom of dug pit, holds condensate &
5) Drinking tube from ... | <urn:uuid:52c97fd0-64c7-4547-8c09-baeae9ad350c> | 3.359375 | 877 | Knowledge Article | Science & Tech. | 42.246346 |
Photograph by Al Giddings
A cloud of hydrothermal fluids streams from a black smoker, or mineral chimney, along the Mid-Ocean Ridge off the west coast of Mexico. Black smokers are common to spreading zones in plate boundaries. Chimneys are made of lead, iron, manganese, and zinc sulfides, through which spew superheated... | <urn:uuid:83fce49c-cee0-4303-82d3-a8719dd6816a> | 3.078125 | 92 | Truncated | Science & Tech. | 49.0875 |
Global surface temperatures………Credit: Berkeley Earth Project
The Global Warming controversy is ended. Right.
Take a look at the graph above. It shows the results of global temperature measurements over a span of some 100-200 years as compiled by four groups: NASA Goddard Institute for Space Studies, NOAA (National Ocea... | <urn:uuid:297397d1-dea7-4a99-ba62-62e8e5b9a67d> | 2.9375 | 821 | Personal Blog | Science & Tech. | 39.098382 |
The book consists of 25 chapters. The initial five chapters introduce paleobotanical history, principles of geologic age, types of plant fossils, and the techniques employed to study them. Chapter 6 deals with Precambrian paleobotany and chapter 7 with the classification of fossil plants. Major groups of fossil plants ... | <urn:uuid:62c27231-7701-4a25-bc1c-0b3ce932ef26> | 3.640625 | 1,013 | Academic Writing | Science & Tech. | 39.899178 |
- Roughly 10 billion icy objects outside the orbit of Neptune.
- Although believed to exist since 1930's, only discovered in 1992 because objects are far away and thus faint.
- Most of the bright KBOs are the same as a 100 watt light bulb on the Moon.
- Exception is Pluto because it is covered by bright frost and so re... | <urn:uuid:d652ae4e-30e1-4af7-93fd-41844355ad8e> | 3.71875 | 107 | Q&A Forum | Science & Tech. | 66.05348 |
- Why Boost?
- What Does Boost Provide?
- What Else?
- Version History
Boost is a free library which is aimed at providing quality software components to developers, whilst using the styles of the Standard Template Library. Some of the components within the library may be put forward as future extensions to the Standar... | <urn:uuid:05036721-a8b1-40c9-bf20-1c8988b3009b> | 2.78125 | 1,592 | Documentation | Software Dev. | 35.696379 |
About 55 million years ago, in the Eocene, volcanic activity spewed enormous amounts of carbon dioxide into the air. The earth warmed by 4-5 degrees Centigrade. All surface ice melted, and every place on earth became tropical, even Antarctica. Sea levels rose a great deal and a significant amount of land was lost to th... | <urn:uuid:84f205b1-ebac-4b78-9eb6-73c588532aab> | 3.671875 | 208 | Personal Blog | Science & Tech. | 51.37125 |
Dark matter’s tendrils revealed
July 5, 2012 | Source: Nature News
A “finger” of the Universe’s dark-matter skeleton, which ultimately dictates where galaxies form, has been observed for the first time.
Researchers have directly detected a slim bridge of dark matter joining two clusters of galaxies, using a technique t... | <urn:uuid:4109f2f8-90ad-4ee0-a7f7-bb14c9188045> | 3.15625 | 427 | Truncated | Science & Tech. | 31.141745 |
A computer system designed to analyse the motion of traffic has found a new role: tracking the movement of sperm to help in the treatment of male infertility.
Geoff Hobson developed the traffic tracking system while a professor at the University of Sheffield. He collaborated with Bill Holt of the Institute of Zoology i... | <urn:uuid:48e6f785-2169-4461-afa5-a286cd68cff4> | 3.265625 | 206 | Truncated | Science & Tech. | 39.628673 |
Evolution by natural selection was an idea revealed to the world 150 years ago tomorrow, by two men, the famous Charles Darwin, and the not so famous Alfred Russel Wallace.
Wallace and Darwin both came up with biology's most important concept and their theory was presented to the Linnean Society in London on 1 July 185... | <urn:uuid:c81655c9-91cb-4b0b-899d-13cd871cf728> | 4.125 | 346 | Knowledge Article | Science & Tech. | 38.498949 |
Search our database of handpicked sites
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.
You searched for
We found 7 results on physics.org and 41 results in our database of sites
40 are Websites,
1 is a Videos,
and 0... | <urn:uuid:83b7b164-1971-4707-a3ca-faa2f730c2e0> | 3.1875 | 328 | Content Listing | Science & Tech. | 64.175685 |
|Dec31-12, 03:07 PM||#1|
ice crystal formation
I have a question regarding the following picture of a lattice of ice:
Why does it form the shape that it does? Is it because of the repulsion of charges from the valence electrons?
|Dec31-12, 03:42 PM||#2|
Ice crystal forms that shape due to hydrogen bonds and due to the ... | <urn:uuid:1e03dc28-54f5-473f-b568-96dde64ae8e1> | 2.765625 | 196 | Comment Section | Science & Tech. | 50.540455 |
June 6, 2011
Astronaut James D. Halsell, Jr., mission commander, uses a Hi-8mm camcorder to videotape the Hand Held Diffusion Test Cells (HHDTC), in the Spacelab Science Module aboard the Earth-orbiting Space Shuttle Columbia. Each test cell has three chambers containing a protein solution, a buffer solution and a prec... | <urn:uuid:3a51a7cf-8d9e-4a98-9907-0aaa6ae31ad2> | 3.140625 | 183 | Truncated | Science & Tech. | 32.630938 |
Since they are typically observed hiding in dark crevices while opening and closing their mouths in an apparently menacing gesture, it isn’t surprising that moray eels get a bad reputation. The fact that their sharp teeth face backward (causing severe damage to anyone trying to pull their hand out of a moray’s mouth) d... | <urn:uuid:b4f76ced-ff40-4095-8ff7-12cfb6e0bb9b> | 3.4375 | 244 | Knowledge Article | Science & Tech. | 47.36875 |
According to NASA probes orbiting Mars and amateur astronomers who are not, a large dust storm is developing on the Red Planet. Dust storms are regular features of the Martian climate, and sometimes they reach incredible size. Sometimes, in fact, they envelope the entire planet. The current storm is not presently threa... | <urn:uuid:6882d70e-0117-425d-9a56-714638857f94> | 3.859375 | 203 | Personal Blog | Science & Tech. | 38.310178 |
CodePy is a C metaprogramming toolkit for Python. It handles two aspects of metaprogramming:
Both capabilities are meant to be used together, but also work on their own. In particular, the code generation facilities work well in conjunction with PyCuda. Dynamic compilation and linking are so far only supported in Linux... | <urn:uuid:0be5af1d-4e3a-4bc5-b0a2-9b9dae021ba2> | 2.78125 | 362 | Documentation | Software Dev. | 40.976353 |
Monday, May 14, 2012 - 13:00 in Biology & Nature
A male robin will be more diligent in caring for its young if the eggs its mate lays are a brighter shade of blue.
- Color of robins' eggs determines parental careMon, 14 May 2012, 16:34:40 EDT
- Mate selection: How does she know he'll take care of the kids?Thu, 18 Jun 2... | <urn:uuid:173ca56c-62fd-4f77-a089-8b854b5bb398> | 2.828125 | 172 | Content Listing | Science & Tech. | 40.201774 |
We all know the sound well. All is peaceful, driving along in the car or sitting in a room listening to a speaker… and all the sudden “blip bzzzzz blaaaaar bzzzzzz”. Something starts buzzing. We all know why; there’s a mobile phone nearby. This noise has somehow become a part of our everyday lives but why does it happe... | <urn:uuid:45c6515c-bdf3-4f97-a862-c89ddee6f3dc> | 3.375 | 931 | Personal Blog | Science & Tech. | 58.578128 |
loop in python
fredrik at pythonware.com
Tue Aug 23 12:31:03 CEST 2005
Steve Holden wrote:
> If you want a fast language, try Holden. I've just invented it.
> Unfortunately it gets the answer to every problem wrong unless the
> answer is 42, but boy it runs quickly. The code for the whole
> interpreter (it's written in... | <urn:uuid:c5d793ec-5963-4fde-917f-30f7063e2eab> | 2.71875 | 256 | Comment Section | Software Dev. | 63.611795 |
Until just a few years ago, scientists were unsure why the global energy budget seemed to indicate that an enormous amount of energy couldn’t be accounted for. Incoming and outgoing radiation is fairly straightforward to measure and a simple energy budget is easy to calculate. Accounting for all of the movement of ener... | <urn:uuid:78363339-5d50-4999-acea-1092055b8700> | 4.125 | 1,643 | Personal Blog | Science & Tech. | 53.239283 |
From Wikipedia, the free encyclopedia
Phononic stop bands are formed for materials with periodic elastic properties. The material does not need to be a crystal.
The basis of phononic crystals dates back to Newton who imagined that sound waves propagated through air in the same way that an elastic wave would propagate a... | <urn:uuid:a316a9eb-c552-4bf5-bd7c-5104f22b5f26> | 3.78125 | 338 | Knowledge Article | Science & Tech. | 44.343333 |
Another global issue that has attracted much popular and scientific interest in
recent years is tropical earth, and few processes are likely to have more
dramatic evidence of our ability to transform the face of the earth, and few
processes are likely to have more profound biological consequences. Humans have
been alte... | <urn:uuid:360e205f-9b90-42b2-9ada-3ef0123b04ef> | 3.71875 | 322 | Truncated | Science & Tech. | 29.983741 |
Seed dispersal mchanisms
remove.this.ecology at ozemail.com.au
Tue Jul 11 18:38:46 EST 2000
I am working with the native Australian tree species Cadellia pentastylis an
obscure species (and a monotypic genus) belonging to the family Surianaceae.
My question relates to seed dispersal mechanisms and whether the strategy
... | <urn:uuid:32039f66-377e-43b3-9f8c-39a10efb3f4f> | 3.5 | 209 | Q&A Forum | Science & Tech. | 46.571442 |
||TNC's Need for Ecoregional Planning Tools
Applications of Sites revised
October 11, 2001
Related Online Resources revised
October 11, 2001
The Nature Conservancy (TNC) recently
initiated a new program of ecoregion-based conservation. The goal of this
effort is to assemble regional portfolios of conservation lands tha... | <urn:uuid:78775954-50cb-473d-82c3-892ea8d2b116> | 2.703125 | 1,297 | Academic Writing | Science & Tech. | 23.126346 |
Earth's major terrestrial, marine, and freshwater ecosystems are known as biomes. They are classified according to similarities in species composition of plants and animals, and by environmental attributes. These attributes include temperature, precipitation, and soil type in terrestrial biomes and temperature, depth, ... | <urn:uuid:b3c3a25d-1b3e-4a5f-bafa-a7dc94f5552a> | 3.953125 | 360 | Knowledge Article | Science & Tech. | 21.993947 |
image credit: William W Nazaroff (2005); image source; larger image
The Geothermal Power Plant
The above photo shows the Nesjavellir geothermal plant in Iceland, which produces power and hot water for the towns surrounding it. To learn more about how the plant works, see this site from the University of Rochester.
Icel... | <urn:uuid:68a8ff1d-96c4-4fbd-9fc3-aa21a17567dd> | 3.8125 | 283 | Knowledge Article | Science & Tech. | 41.483548 |
Hadley Crater Perspective View
About this Image
This computer-generated perspective view of Hadley Crater was created using data obtained from the High-Resolution Stereo Camera (HRSC) on ESA’s Mars Express. Centred at around 19°S and 157°E, this image has a ground resolution of about 19 m per pixel. The ejecta blanket ... | <urn:uuid:d41119dc-ecb1-4ad3-aa76-578d8e407fed> | 3.828125 | 194 | Truncated | Science & Tech. | 48.255245 |
From the shiny, strong nacre that gives abalone shells an unbreakable, opaline sheen, to the goopy mix of proteins fired by a velvet worm that solidify and trap prey upon impact, nature is packed with inspiration for scientists designing new materials.
Waterproof adhesives and self-cleaning s... Read More
We continue o... | <urn:uuid:885c5ee6-76d7-4055-b899-d6771913dab1> | 2.75 | 1,020 | Content Listing | Science & Tech. | 25.015996 |
One of the most important features of this universal object is it’s ability to display not only a static text, but expressions as well. Expressions can be located in the object together with text. Let us examine a simple example of how it can be performed. Put the following line into the object:
Hello, World! Today is ... | <urn:uuid:a8573f72-ea97-4dab-8883-7ed07f83046d> | 2.765625 | 603 | Documentation | Software Dev. | 49.343278 |
ucleic acid precipitation - why alchohol and low temperature (Jan/29/2002 )
Would anyone out there be able to tell as to why alchohols like isopropanol or ethanol are used to precipitate nucleic acids, and also, why is the precipitation done at low temperatures
Precipitation is probably easier at lower temperatures bec... | <urn:uuid:632e0d1e-f2ef-4aa6-ac6d-173ea103afa0> | 2.734375 | 347 | Comment Section | Science & Tech. | 28.673325 |