Random Articles (Page 54)

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πŸ”— Cyclorama

πŸ”— Visual arts

A cyclorama is a panoramic image on the inside of a cylindrical platform, designed to give viewers standing in the middle of the cylinder a 360Β° view, and also a building designed to show a panoramic image. The intended effect is to make viewers, surrounded by the panoramic image, feel as if they were standing in the midst of the place depicted in the image.

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πŸ”— The ADE 651 is a fake bomb detector, sold for up to US$60k each

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Military history/Weaponry πŸ”— Skepticism πŸ”— Law Enforcement πŸ”— Iraq πŸ”— British crime πŸ”— Explosives

The ADE 651 is a fake bomb detector produced by the British company Advanced Tactical Security & Communications Ltd (ATSC). Its manufacturer claimed it could detect bombs, guns, ammunition, and more from kilometers away. However, it was a scam, and the device was little more than a dowsing rod. The device was sold for up to US$60,000 each, despite costing almost nothing to produce. It was widely used in the Middle East, and may have led to numerous deadly bombings in Iraq due to its inability to detect explosives. Its inventor, James McCormick, was sentenced to 10 years in prison in 2013 for fraud.

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πŸ”— The eastern coyote, a wild N. American canine with coyote-wolf and dog parentage

πŸ”— Dogs

The eastern coyote (Canis latrans var.) is a wild North American canine of both coyote and wolf parentage. The hybridization likely first occurred in the Great Lakes region, as western coyotes moved east. It was first noticed during the early 1930s to the late 1940s, and likely originated in the aftermath of the extirpation of the gray wolf in southeastern Ontario, Labrador and Quebec, thus allowing coyotes to colonize the former wolf ranges and mix with the remnant wolf populations. This hybrid is smaller than the eastern wolf and holds smaller territories, but is larger and holds more extensive home ranges than the typical western coyote.

πŸ”— Mariko Aoki Phenomenon

πŸ”— Books πŸ”— Psychology πŸ”— Japan

The Mariko Aoki phenomenon (ι’ζœ¨γΎγ‚Šγ“ηΎθ±‘, Aoki Mariko genshō) is a Japanese expression referring to an urge to defecate that is suddenly felt after entering bookstores. The phenomenon's name derives from the name of the woman who mentioned the phenomenon in a magazine article in 1985. According to Japanese social psychologist Shozo Shibuya, the specific causes that trigger a defecation urge in bookstores are not yet clearly understood (as of 2014). There are also some who are skeptical about whether such a peculiar phenomenon really exists at all, and it is sometimes discussed as one type of urban myth.

The series of processes through which being in a bookstore leads to an awareness of a defecation urge is something that cannot be explained from a medical perspective as a single pathological concept, at least at present. According to a number of discussions on the topic, even if it can be sufficiently found that this phenomenon actually exists, it is a concept that would be difficult to be deemed a specific pathological entity (such as a "Mariko Aoki disease", for example). On the other hand, it is also a fact that a considerable number of the intellectuals (particularly clinicians) who discuss this phenomenon have adopted existing medical terminology such as from diagnostics and pathology. Borrowing from this approach, this article also uses expressions from existing medical terminology for convenience.

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πŸ”— Uranium can be extracted from seawater in useful amounts

πŸ”— Energy πŸ”— Mining

Uranium mining is the process of extraction of uranium ore from the ground. The worldwide production of uranium in 2019 amounted to 53,656Β tonnes. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account for 68% of world production. Other countries producing more than 1,000 tonnes per year included Namibia, Niger, Russia, Uzbekistan, the United States, and China. Nearly all of the world's mined uranium is used to power nuclear power plants.

Uranium is mined by in-situ leaching (57% of world production) or by conventional underground or open-pit mining of ores (43% of production). During in-situ mining, a leaching solution is pumped down drill holes into the uranium ore deposit where it dissolves the ore minerals. The uranium-rich fluid is then pumped back to the surface and processed to extract the uranium compounds from solution. In conventional mining, ores are processed by grinding the ore materials to a uniform particle size and then treating the ore to extract the uranium by chemical leaching. The milling process commonly yields dry powder-form material consisting of natural uranium, "yellowcake," which is sold on the uranium market as U3O8.

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πŸ”— A baboon who acted as assistant to a disabled railway signalman in South Africa

πŸ”— Human rights πŸ”— Disability πŸ”— South Africa πŸ”— Primates

Jack (died 1890) was a chacma baboon, who attained some fame for acting as an assistant to a disabled railway signalman in South Africa.

πŸ”— Ataraxia

πŸ”— Medicine πŸ”— Philosophy πŸ”— Philosophy/Ancient philosophy

In Ancient Greek philosophy, ataraxia (Greek: ἀταραξία, from αΌ€- indicating negation or absence and ταραχ- tarach- 'to disturb, trouble' with the abstract noun suffix -Ξ―Ξ±), generally translated as 'unperturbedness', 'imperturbability', 'equanimity', or 'tranquility', is a lucid state of robust equanimity characterized by ongoing freedom from distress and worry. In non-philosophical usage, ataraxia was the ideal mental state for soldiers entering battle. Achieving ataraxia is a common goal for Pyrrhonism, Epicureanism, and Stoicism, but the role and value of ataraxia within each philosophy varies in accordance with their philosophical theories. The mental disturbances that prevent one from achieving ataraxia also vary among the philosophies, and each philosophy has a different understanding as to how to achieve ataraxia.

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πŸ”— Galactic Algorithm

A galactic algorithm is one that runs faster than any other algorithm for problems that are sufficiently large, but where "sufficiently large" is so big that the algorithm is never used in practice. Galactic algorithms were so named by Richard Lipton and Ken Regan, as they will never be used on any of the merely terrestrial data sets we find here on Earth.

An example of a galactic algorithm is the fastest known way to multiply two numbers, which is based on a 1729-dimensional Fourier transform. This means it will not reach its stated efficiency until the numbers have at least 2172912 bits (at least 101038 digits), which is vastly larger than the number of atoms in the known universe. So this algorithm is never used in practice.

Despite the fact that they will never be used, galactic algorithms may still contribute to computer science:

  • An algorithm, even if impractical, may show new techniques that may eventually be used to create practical algorithms.
  • Computer sizes may catch up to the crossover point, so that a previously impractical algorithm becomes practical.
  • An impractical algorithm can still demonstrate that conjectured bounds can be achieved, or alternatively show that conjectured bounds are wrong. As Lipton says "This alone could be important and often is a great reason for finding such algorithms. For example, if tomorrow there were a discovery that showed there is a factoring algorithm with a huge but provably polynomial time bound, that would change our beliefs about factoring. The algorithm might never be used, but would certainly shape the future research into factoring." Similarly, a O ( n 2 100 ) {\displaystyle O\left(n^{2^{100}}\right)} algorithm for the Boolean satisfiability problem, although unusable in practice, would settle the P versus NP problem, the most important open problem in computer science and one of the Millennium Prize Problems.

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πŸ”— Glossary of Japanese words of Portuguese origin

πŸ”— Portugal πŸ”— Japan πŸ”— Glossaries

Many Japanese words of Portuguese origin entered the Japanese language when Portuguese Jesuit priests introduced Christian ideas, Western science, technology and new products to the Japanese during the Muromachi period (15th and 16th centuries).

The Portuguese were the first Europeans to reach Japan and the first to establish direct trade between Japan and Europe, in 1543. During the 16th and 17th century, Portuguese Jesuits had undertaken a great work of Catechism, that ended only with religious persecution in the early Edo period (Tokugawa Shogunate). The Portuguese were the first to translate Japanese to a Western language, in the Nippo Jisho (ζ—₯θ‘‘θΎžζ›Έ, literally the "Japanese-Portuguese Dictionary") or Vocabulario da Lingoa de Iapam compiled by Portuguese Jesuit JoΓ£o Rodrigues, and published in Nagasaki in 1603, who also wrote a grammar Arte da Lingoa de Iapam (ζ—₯ζœ¬ε€§ζ–‡ε…Έ, nihon daibunten). The dictionary of Japanese-Portuguese explained 32,000 Japanese words translated into Portuguese. Most of these words refer to the products and customs that first came to Japan via the Portuguese traders.

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πŸ”— Novikov Self-Consistency Principle

πŸ”— Russia πŸ”— Physics πŸ”— Physics/relativity πŸ”— Russia/science and education in Russia

The Novikov self-consistency principle, also known as the Novikov self-consistency conjecture and Larry Niven's law of conservation of history, is a principle developed by Russian physicist Igor Dmitriyevich Novikov in the mid-1980s. Novikov intended it to solve the problem of paradoxes in time travel, which is theoretically permitted in certain solutions of general relativity that contain what are known as closed timelike curves. The principle asserts that if an event exists that would cause a paradox or any "change" to the past whatsoever, then the probability of that event is zero. It would thus be impossible to create time paradoxes.