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🔗 Potemkin Village

🔗 Russia 🔗 History 🔗 Skepticism 🔗 Sociology 🔗 Russia/language and literature of Russia 🔗 Russia/history of Russia

In politics and economics, a Potemkin village is any construction (literal or figurative) whose sole purpose is to provide an external façade to a country which is faring poorly, making people believe that the country is faring better, although statistics and charts would state otherwise. The term comes from stories of a fake portable village built solely to impress Empress Catherine II by her former lover Grigory Potemkin, during her journey to Crimea in 1787. While modern historians claim accounts of this portable village are exaggerated, the original story was that Potemkin erected phony portable settlements along the banks of the Dnieper River in order to impress the Russian Empress; the structures would be disassembled after she passed, and re-assembled farther along her route to be viewed again as if another example. The term is a translation of the Russian: потёмкинские деревни (IPA: /pɐˈtʲɵmkʲɪnskʲɪɪ dʲɪˈrʲɛvnʲɪ/; romanization: potyómkinskiye derévni).

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🔗 Iloveyou

🔗 Computer Security 🔗 Computer Security/Computing 🔗 Tambayan Philippines

ILOVEYOU, sometimes referred to as Love Bug or Love Letter for you, is a computer worm that infected over ten million Windows personal computers on and after 4 May 2000 when it started spreading as an email message with the subject line "ILOVEYOU" and the attachment "LOVE-LETTER-FOR-YOU.txt.vbs". The latter file extension ('vbs', a type of interpreted file) was most often hidden by default on Windows computers of the time (as it is an extension for a file type that is known by Windows), leading unwitting users to think it was a normal text file. Opening the attachment activates the Visual Basic script. The worm inflicts damage on the local machine, overwriting random types of files (including Office files, image files, and audio files; however after overwriting MP3 files the virus hides the file), and sends a copy of itself to all addresses in the Windows Address Book used by Microsoft Outlook. This made it spread much faster than any other previous email worm.

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🔗 Karmarkar's algorithm – Patent controversy – can mathematics be patented?

🔗 Mathematics

Karmarkar's algorithm is an algorithm introduced by Narendra Karmarkar in 1984 for solving linear programming problems. It was the first reasonably efficient algorithm that solves these problems in polynomial time. The ellipsoid method is also polynomial time but proved to be inefficient in practice.

Denoting n {\displaystyle n} as the number of variables and L {\displaystyle L} as the number of bits of input to the algorithm, Karmarkar's algorithm requires O ( n 3.5 L ) {\displaystyle O(n^{3.5}L)} operations on O ( L ) {\displaystyle O(L)} -digit numbers, as compared to O ( n 6 L ) {\displaystyle O(n^{6}L)} such operations for the ellipsoid algorithm. The runtime of Karmarkar's algorithm is thus

O ( n 3.5 L 2 log L log log L ) , {\displaystyle O(n^{3.5}L^{2}\cdot \log L\cdot \log \log L),}

using FFT-based multiplication (see Big O notation).

Karmarkar's algorithm falls within the class of interior-point methods: the current guess for the solution does not follow the boundary of the feasible set as in the simplex method, but moves through the interior of the feasible region, improving the approximation of the optimal solution by a definite fraction with every iteration and converging to an optimal solution with rational data.

🔗 Decline in Insect Populations

🔗 Environment 🔗 Insects 🔗 Ecology

An increasing number of scientific studies are reporting substantial declines in insect populations worldwide. Most commonly, the declines involve reductions in abundance, though in some cases entire species are going extinct. The declines are far from uniform. In some localities, there have been reports of increases in overall insect population, and some types of insects appear to be increasing in abundance across the world.

Some of the insects most affected include bees, butterflies, moths, beetles, dragonflies and damselflies. Anecdotal evidence has been offered of much greater apparent abundance of insects in the 20th century; recollections of the windscreen phenomenon are an example.

Possible causes are similar to other biodiversity loss, with studies identifying: habitat destruction, including intensive agriculture; the use of pesticides (particularly insecticides); urbanization, and industrialization; introduced species; and climate change. Not all insect orders are affected in the same way; many groups are the subject of limited research, and comparative figures from earlier decades are often not available.

In response to the reported declines, increased insect related conservation measures have been launched. In 2018 the German government initiated an "Action Programme for Insect Protection", and in 2019 a group of 27 British entomologists and ecologists wrote an open letter calling on the research establishment in the UK "to enable intensive investigation of the real threat of ecological disruption caused by insect declines without delay".

🔗 Optimal Stopping

🔗 Mathematics 🔗 Statistics

In mathematics, the theory of optimal stopping or early stopping is concerned with the problem of choosing a time to take a particular action, in order to maximise an expected reward or minimise an expected cost. Optimal stopping problems can be found in areas of statistics, economics, and mathematical finance (related to the pricing of American options). A key example of an optimal stopping problem is the secretary problem. Optimal stopping problems can often be written in the form of a Bellman equation, and are therefore often solved using dynamic programming.

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🔗 Terahertz Gap

🔗 Technology 🔗 Physics 🔗 Radio 🔗 Astronomy 🔗 Engineering

In engineering, the terahertz gap is a frequency band in the terahertz region of the electromagnetic spectrum between radio waves and infrared light for which practical technologies for generating and detecting the radiation do not exist. It is defined as 0.1 to 10 THz (wavelengths of 3 mm to 30 µm). Currently, at frequencies within this range, useful power generation and receiver technologies are inefficient and unfeasible.

Mass production of devices in this range and operation at room temperature (at which energy k·T is equal to the energy of a photon with a frequency of 6.2 THz) are mostly impractical. This leaves a gap between mature microwave technologies in the highest frequencies of the radio spectrum and the well developed optical engineering of infrared detectors in their lowest frequencies. This radiation is mostly used in small-scale, specialized applications such as submillimetre astronomy. Research that attempts to resolve this issue has been conducted since the late 20th century.

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🔗 A True Story

🔗 Ancient Near East 🔗 Novels 🔗 Novels/Science fiction 🔗 Science Fiction 🔗 Skepticism 🔗 Literature 🔗 Classical Greece and Rome 🔗 Greece 🔗 Comedy 🔗 Assyria

A True Story (Ancient Greek: Ἀληθῆ διηγήματα, Alēthē diēgēmata; Latin: Vera Historia or Latin: Verae Historiae) is a novel written in the second century AD by Lucian of Samosata, a Greek-speaking author of Assyrian descent. The novel is a satire of outlandish tales which had been reported in ancient sources, particularly those which presented fantastic or mythical events as if they were true. It is Lucian's best-known work.

It is the earliest known work of fiction to include travel to outer space, alien lifeforms, and interplanetary warfare. As such, A True Story has been described as "the first known text that could be called science fiction". However the work does not fit into typical literary genres: its multilayered plot and characters have been interpreted as science fiction, fantasy, satire or parody, and have been the subject of much scholarly debate.

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🔗 Foldering

🔗 Internet 🔗 Computer Security 🔗 Computer Security/Computing

Foldering is the practice of communicating via messages saved to the "drafts" folder of an email or other electronic messaging account that is accessible by multiple people. The messages are never actually sent.

Foldering has been described as a digital equivalent of a dead drop.

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🔗 Digital Radio Frequency Memory (DRFM)

Digital Radio Frequency Memory (DRFM) is an electronic method for digitally capturing and retransmitting RF signals. DRFM systems are typically used in radar jamming, although applications in cellular communications are becoming more common.