18 APR 2014 by ideonexus

 Early Statement on the Scientific Method

From Alhazen.
Folksonomies: science scientific method
Folksonomies: science scientific method
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The seeker after truth is not one who studies the writings of the ancients and, following his natural disposition, puts his trust in them, but rather the one who suspects his faith in them and questions what he gathers from them, the one who submits to argument and demonstration and not the sayings of human beings whose nature is fraught with all kinds of imperfection and deficiency. Thus the duty of the man who investigates the writings of scientists, if learning the truth is his goal, is to make himself an enemy of all that he reads, and, applying his mind to the core and margins of of its content, attack it from every side. he should also suspect himself as he performs his critical examination of it, so that he may avoid falling into either prejudice or leniency.

22 MAR 2014 by ideonexus

 The Mentat Must be a Generalist

Sounds like the fox and the hedgehog.
Folksonomies: fox hedgehog dichotomies
Folksonomies: fox hedgehog dichotomies
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Above all else, the mentat must be a generalist, not a specialist. It is wise to have decisions of great moment monitored by generalists. Experts and specialists lead you quickly into chaos. They are a source of useless nit-picking, the ferocious quibble over a comma. The mentat-generalist, on the other hand, should bring to decision-making a healthy common sense. He must not cut himself off from the broad sweep of what is happening in his universe. He must remain capable of saying: "There's no real mystery about this at the moment. This is what we want now. It may prove wrong later, but we'll correct that when we come to it." The mentat-generalist must understand that anything which we can identify as our universe is merely a part of larger phenomena. But the expert looks backward; he looks into the narrow standards of his own specialty. The generalist looks outward; he looks for living principles, knowing full well that such principles change, that they develop. It is to the characteristics of change itself that the mentat-generalist must look. There can be no permanent catalogue of such change, no handbook or manual. You must look at it with as few preconceptions as possible, asking yourself: "Now what is this thing doing?"

22 MAR 2014 by koo5

 What You Can't Say

http://www.paulgraham.com/say.html
Folksonomies: taboo
Folksonomies: taboo
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To launch a taboo, a group has to be poised halfway between weakness and power. A confident group doesn't need taboos to protect it. It's not considered improper to make disparaging remarks about Americans, or the English. And yet a group has to be powerful enough to enforce a taboo. Coprophiles, as of this writing, don't seem to be numerous or energetic enough to have had their interests promoted to a lifestyle.

I suspect the biggest source of moral taboos will turn out to be power struggles in which one side only barely has the upper hand. That's where you'll find a group powerful enough to enforce taboos, but weak enough to need them.

22 MAR 2014 by koo5

 getting water from air

lostinscience.wordpress.com/2012/12/08/how-to-make-a-self-filling-water-bottle/
Folksonomies: water
Folksonomies: water
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in 2011 an Australian inventor won the James Dyson Award for a device that cools the air using underground coils, so you only need enough energy to pump the air down a pipe.

Another low energy technique is that used in the Atacama Desert in Chile, and is basically just a piece of mesh strung between two poles, with a trough under it. They get a fog too, and as it flows through the mesh, drops of water condense and run down into the trough.

But NBD Nano claim that the beetle’s skin is several times more efficient than the Chilean method. So far they claim a square metre of beetle-inspired material, at 21 °C and 75% relative humidity, can produce 3 litres of water per hour.

Energy is still used to blow air across the collector,

17 MAR 2014 by ideonexus

 Spider Trap

An infinite-recursion website that lures web-crawlers into an infinite-indexing loop.
Folksonomies: computer science hacking
Folksonomies: computer science hacking
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spider trap (or crawler trap) is a set of web pages that may intentionally or unintentionally be used to cause a web crawler or search bot to make an infinite number of requests or cause a poorly constructed crawler to crash. Web crawlers are also called web spiders, from which the name is derived. Spider traps may be created to "catch" spambots or other crawlers that waste a website's bandwidth. They may also be created unintentionally by calendars that use dynamic pages with links that continually point to the next day or year.

Common techniques used are:

  • creation of indefinitely deep directory structures like
    http://foo.com/bar/foo/bar/foo/bar/foo/bar/.....
    
  • Dynamic pages that produce an unbounded number of documents for a web crawler to follow. Examples include calendars[citation needed] and algorithmically generated language poetry.[1]
  • documents filled with a large number of characters, crashing the lexical analyzer parsing the document.
  • documents with session-id's based on required cookies.

There is no algorithm to detect all spider traps. Some classes of traps can be detected automatically, but new, unrecognized traps arise quickly.

 

 spider trap causes a web crawler to enter something like an infinite loop, which wastes the spider's resources, lowers its productivity, and, in the case of a poorly written crawler, can crash the program. Polite spiders alternate requests between different hosts, and don't request documents from the same server more than once every several seconds, meaning that a "polite" web crawler is affected to a much lesser degree than an "impolite" crawler.

In addition, sites with spider traps usually have a robots.txt telling bots not to go to the trap, so a legitimate "polite" bot would not fall into the trap, whereas an "impolite" bot which disregards the robots.txt settings would be affected by the trap.

16 MAR 2014 by ideonexus

 Mentor Texts

Texts that teach children.
Folksonomies: reading education
Folksonomies: reading education
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One of the most powerful writing/language arts components of the MPS Comprehensive Literacy Plan (CLP) is the robust use of mentor texts across all grade levels. A mentor text is a piece of writing (book, article, pamphlet, caption, etc.) used to exemplify a specific aspect of writers’ craft. Mentor texts are used during both whole and small group instruction. Teachers purposefully select and intentionally read aloud from mentor texts to guide student as they work to apply similar writing techniques. Through repetitive use, selected mentor texts become extremely familiar to students. They come to recognize, understand, and mimic a variety of literary techniques authors employed in various pieces. Later in the instructional process teachers can suggest a range of mentor texts to study and learn from—always with the goal of applying recognized techniques to enhance the quality of their writing. After learning from teachers’ think aloud strategies, students will eventually share in the selection of mentor texts as they become more sophisticated consumers of the elements of authors’ craft. The ultimate goal of the use of mentor texts is for students to take what they have learned from a variety of authors and apply these practices as they continue to develop their own writing styles.

There are three types of mentor texts: anchor texts, text sets, and touchstone texts. An anchor text is a reliable piece of quality writing introduced to the whole class to exemplify specific elements of writers’ craft. Text sets are collections of texts grouped together because they have some element of writers’ craft in common. Touchstone texts are those texts that grade-level or common-course teachers agree to use during whole group instruction, so that every student is “touched” by the experience. Teachers in each grade level or course make local decisions based on their students’ needs. By the end of a student’s K-12 education he or she will harvest a healthy array of mentor texts that contribute to his or her textual lineage (Tatum, 2009).

16 MAR 2014 by ideonexus

 Simultaneous Invention

Inventions being discovered simultaneously is not just coincidence, it's a regular phenomenon.
Folksonomies: invention synchronicity
Folksonomies: invention synchronicity
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Thomas Edison invented the light bulb in 1879. What if he had never been born, Would we still have light bulbs? And would they still have been invented in 1879? It turns out that this is not just a philosophical question and the answer is yes, the light bulb would have been invented at roughly the same time. We know this because at least 23 other people built prototype light bulbs before Edison1, including two groups who filed patents and fought legal battles with him over the rights (Sawyer and Mann in the U.S. and Swan in England)2.

This is not a strange coincidence that happened with electric lighting, it is the norm in both technological invention and scientific and mathematical discovery. Newton and Leibniz independently invented calculus, Alexander Graham Bell and Elisha Gray both filed a patent for the telephone on the same day — within three hours of each other — and sunspots were simultaneously discovered by four scientists living in four different countries. The list of simultaneous independent inventions includes the airplane (2 people), the steamboat (5 people), photography (2 people), the telegraph (5 people), and the telescope (9 people). In science and math it includes decimal fractions (2 people), the theory of natural selection (2 people), the discovery of oxygen (2 people), molecular theory (2 people), and the conservation of energy (4 people)3

A study by Ogburn and Thomas4 in 1922 produced a list of 148 major inventions and discoveries that were made independently by two or more groups at the same time. A similar study by Merton5 in 1960 led him to conclude that “the pattern of independent multiple discoveries in science is in principle the dominant pattern, rather than a subsidiary one”. Lest you think that only the landmark discoveries covered in these surveys are subject to multiple invention, recent work by Lemley6 suggests that 90-98% of patent lawsuits are filed against independent inventors and not copiers. Even the idea that multiple simultaneous invention is the norm was advanced by multiple independent groups at the same time7.

16 MAR 2014 by ideonexus

 The Nintendo Effect

Nintendo has tapped into the secret of keeping kids engaged for hours.
Folksonomies: education gamification
Folksonomies: education gamification
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Technology can play an important role, but we haven’t had the time or wherewithal to explore it fully. I’m waiting for a breakthrough process, which I think may happen in mathematics. The people at Nintendo figured out billions of dollars ago that you pull kids in, you get them engaged, and that’s the model: engagement of intensive focused effort. The result is rapid incremental development of new skills and capabilities. These kids operate at a speed and accuracy level unheard of outside game playing. We have to take that model and translate it to mathematics, to grammar, to the dynamics of social interaction and political structures.

16 MAR 2014 by ideonexus

 Dyson Spheres

The energy and time required to dismantle a planet and turn it into a biosphere surrounding a sun.
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The material factors which ultimately limit the expansion of a technically advanced species are the supply of matter and the supply of energy. At present the material resources being exploited by the human species are roughly limited to the biosphere of the earth, a mass of the order of 5 X 10^19 grams. Our present energy supply may be generously estimated at 10^20 ergs per second. The quantities of matter and energy which might conceivably become accessible to us within the solar system are 2 X 10^30 grams (the mass of Jupiter) and 4 X 10^33 ergs per second (the total energy output of the sun).

The reader may well ask in what sense can anyone speak of the mass of Jupiter or the total radiation from the sun as being accessible to exploitation. The following argument is intended to show that an exploitation of this magnitude is not absurd. First of all, the time required for an expansion of population and industry by a factor of 10^12 is quite short, say 3000 years if an average growth rate of 1 percent per year is maintained. Second, the energy required to disassemble and rearrange a planet of the size of Jupiter is about 10^44 ergs, equal to the energy radiated by tlhe sun in 800 years. Third, the mass of Jupiter, if distributed in a spherical shell revolving around the sun at twice the Earth's distance from it, would have a thickness such that the mass is 200 grams per square centimeter of surface area (2 to 3 meters, depending on the density). A shell of this thickness could be made comfortably habitable, and could contain all the machinery required for exploiting the solar radiation falling onto it from the inside.

It is remarkable that the time scale ozf industrial expansion, the mass of Jupiter, the energy output of the sun, and the thickness of a habitable biosphere all have consistent orders of magnitude. It seems, then, a reasonable expectation that, barring accidents, Malthusian pressures will ultimately drive an intelligent species to adopt some such efficient exploitation of its available resources. One should expect that, within a few thousand years of its entering the stage of industrial development, any intelligent species should be found occupying an artificial biosphere which completely surrounds its parent star.

16 MAR 2014 by ideonexus

 Seeing Dyson Civilizations

How difficult would it be to detect their heat signature?
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In summary, the circumstellar shells of Dyson civilizations-at temperatures ~300 degrees K and radii ~1 a.u.--can be detected with existing telescopes and state-of-the-art infrared detectors in the 8-13-u window out to distances of several hundred parsecs. But discrimination of Dyson civilizations from naturally occurring low-temperature objects is very difficult, unless Dyson civilizations have some further distinguishing feature, such as monochromatic radio-frequency emission.