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🔗 Linguistics 🔗 Linguistics/Applied Linguistics 🔗 Writing systems

The orthographic depth of an alphabetic orthography indicates the degree to which a written language deviates from simple one-to-one letter–phoneme correspondence. It depends on how easy it is to predict the pronunciation of a word based on its spelling: shallow orthographies are easy to pronounce based on the written word, and deep orthographies are difficult to pronounce based on how they are written.

In shallow orthographies, the spelling-sound correspondence is direct: from the rules of pronunciation, one is able to pronounce the word correctly. In other words, shallow (transparent) orthographies, also called phonemic orthographies, have a one-to-one relationship between its graphemes and phonemes, and the spelling of words is very consistent. Such examples include Hindi, Spanish, Finnish, Turkish, Latin and Italian.

In contrast, in deep (opaque) orthographies, the relationship is less direct, and the reader must learn the arbitrary or unusual pronunciations of irregular words. In other words, deep orthographies are writing systems that do not have a one-to-one correspondence between sounds (phonemes) and the letters (graphemes) that represent them. They may reflect etymology (English, Faroese, Mongolian script, Thai, French, or Franco-Provençal) or be morphophonemic (Korean or Russian).

Written Korean represents an unusual hybrid; each phoneme in the language is represented by a letter but the letters are packaged into "square" units of two to four phonemes, each square representing a syllable. Korean has very complex phonological variation rules, especially regarding the consonants rather than the vowels, in contrast to English. For example, the Korean word 훗일, which should be pronounced as [husil] based on standard pronunciations of the components of the grapheme, is actually pronounced as [hunnil]. Among the consonants of the Korean language, only one is always pronounced exactly as it is written.

Italian offers clear examples of differential directionality in depth. Even in a very shallow orthographic system, spelling-to-pronunciation and pronunciation-to-spelling may not be equally clear. There are two major imperfect matches of vowels to letters: in stressed syllables, e can represent either open [ɛ] or closed [e], and o stands for either open [ɔ] or closed [o]. According to the orthographic principles used for the language, [ˈsɛtta] 'sect', for example, with open [ɛ] can only be spelled setta, and [ˈvetta] 'summit' with closed [e] can only be vetta — if a listener can hear it, they can spell it. But since the letter e is assigned to represent both [ɛ] and [e], there is no principled way to know whether to pronounce the written words setta and vetta with [ɛ] or [e] — the spelling does not present the information needed for accurate pronunciation. A second lacuna in Italian's shallow orthography is that although stress position in words is only very partially predictable, it is normally not indicated in writing. For purposes of spelling, it makes no difference which syllable is stressed in the place names Arsoli and Carsoli, but the spellings offer no clue that they are ARsoli and CarSOli (and as with the letter e above, the stressed o of Carsoli, which is [ɔ], is unknown from the spelling).

🔗 Physics 🔗 Physics/relativity

In physics, there is a speculative hypothesis that, if there were a black hole with the same mass, charge and angular momentum as an electron, it would share other properties of the electron. Most notably, Brandon Carter showed in 1968 that the magnetic moment of such an object would match that of an electron. This is interesting because calculations ignoring special relativity and treating the electron as a small rotating sphere of charge give a magnetic moment roughly half the experimental value (see Gyromagnetic ratio).

However, Carter's calculations also show that a would-be black hole with these parameters would be "super-extremal". Thus, unlike a true black hole, this object would display a naked singularity, meaning a singularity in spacetime not hidden behind an event horizon. It would also give rise to closed timelike curves.

Standard quantum electrodynamics (QED), currently the most comprehensive theory of particles, treats the electron as a point particle. There is no evidence that the electron is a black hole (or naked singularity) or not. Furthermore, since the electron is quantum-mechanical in nature, any description purely in terms of general relativity is paradoxical until a better model based on understanding of quantum nature of blackholes and gravitational behaviour of quantum particles is developed by research. Hence, the idea of a black hole electron remains strictly hypothetical.

🔗 Computing 🔗 New Zealand

The Aamber Pegasus is a home computer first produced in New Zealand in 1981 by Technosys Research Labs.

The hardware was designed by Stewart J Holmes. The software was designed by Paul Gillingwater, Nigel Keam and Paul Carter.

It is thought that Apple Computers introduction of the Apple II computer into the New Zealand market, and its subsequent heavy educational discounting was the final nail in the coffin for Technosys and the Aamber Pegasus computer. Total production numbers are unknown, but it is thought "around one hundred" were sold.

🔗 Physics 🔗 Astronomy

A helium flash is a very brief thermal runaway nuclear fusion of large quantities of helium into carbon through the triple-alpha process in the core of low mass stars (between 0.8 solar masses (M_☉) and 2.0 M_☉) during their red giant phase. The Sun is predicted to experience a flash 1.2 billion years after it leaves the main sequence. A much rarer runaway helium fusion process can also occur on the surface of accreting white dwarf stars.

Low-mass stars do not produce enough gravitational pressure to initiate normal helium fusion. As the hydrogen in the core is exhausted, some of the helium left behind is instead compacted into degenerate matter, supported against gravitational collapse by quantum mechanical pressure rather than thermal pressure. Subsequent hydrogen shell fusion further increases the mass of the core until it reaches temperature of approximately 100 million kelvin, which is hot enough to initiate helium fusion (or "helium burning") in the core.

However, a fundamental quality of degenerate matter is that increases in temperature do not produce an increase in the pressure of the matter until the thermal pressure becomes so very high that it exceeds degeneracy pressure. In main sequence stars, thermal expansion regulates the core temperature, but in degenerate cores, this does not occur. Helium fusion increases the temperature, which increases the fusion rate, which further increases the temperature in a runaway reaction which quickly spans the entire core. This produces a flash of very intense helium fusion that lasts only a few minutes, but during that time, produces energy at a rate comparable to the entire Milky Way galaxy.

In the case of normal low-mass stars, the vast energy release causes much of the core to come out of degeneracy, allowing it to thermally expand. This consumes most of the total energy released by the helium flash, and any left-over energy is absorbed into the star's upper layers. Thus the helium flash is mostly undetectable by observation, and is described solely by astrophysical models. After the core's expansion and cooling, the star's surface rapidly cools and contracts in as little as 10,000 years until it is roughly 2% of its former radius and luminosity. It is estimated that the electron-degenerate helium core weighs about 40% of the star mass and that 6% of the core is converted into carbon.

🔗 Judaism 🔗 Writing systems 🔗 Kabbalah

Gematria (; Hebrew: גמטריא or gimatria גימטריה, plural גמטראות or גימטריאות, gimatriot) is the practice of assigning a numerical value to a name, word or phrase by reading it as a number, or sometimes by using an alphanumerical cipher. The letters of the alphabets involved have standard numerical values, but a word can yield several values if a cipher is used.

According to Aristotle (384–322 BCE), isopsephy, based on the Milesian numbering of the Greek alphabet developed in the Greek city of Miletus, was part of the Pythagorean tradition, which originated in the 6th century BCE. The first evidence of use of Hebrew letters as numbers dates to 78 BCE; gematria is still used in Jewish culture. Similar systems have been used in other languages and cultures, derived from or inspired by either Greek isopsephy or Hebrew gematria, and include Arabic abjad numerals and English gematria.

The most common form of Hebrew gematria is used in the Talmud and Midrash, and elaborately by many post-Talmudic commentators. It involves reading words and sentences as numbers, assigning numerical instead of phonetic value to each letter of the Hebrew alphabet. When read as numbers, they can be compared and contrasted with other words or phrases – cf. the Hebrew proverb נכנס יין יצא סוד (nichnas yayin yatza sod, lit. 'wine entered, secret went out', i.e. "in vino veritas"). The gematric value of יין ('wine') is 70 (י=10; י=10; ן=50) and this is also the gematric value of סוד ('secret', ס=60; ו=6; ד=4)‎.

Although a type of gematria system ('Aru') was employed by the ancient Babylonian culture, their writing script was logographic, and the numerical assignments they made were to whole words. Aru was very different from the Milesian systems used by Greek and Hebrew cultures, which used alphabetic writing scripts. The value of words with Aru were assigned in an entirely arbitrary manner and correspondences were made through tables, and so cannot be considered a true form of gematria.

Gematria sums can involve single words, or a string of lengthy calculations. A short example of Hebrew numerology that uses gematria is the word חי (chai, lit. 'alive'), which is composed of two letters that (using the assignments in the mispar gadol table shown below) add up to 18. This has made 18 a "lucky number" among the Jewish people. Donations of money in multiples of 18 are very popular.

In early Jewish sources, the term can also refer to other forms of calculation or letter manipulation, for example atbash.

🔗 Electronics

In signal processing, the Nyquist frequency (or folding frequency), named after Harry Nyquist, is a characteristic of a sampler, which converts a continuous function or signal into a discrete sequence. For a given sampling rate (samples per second), the Nyquist frequency (cycles per second) is the frequency whose cycle-length (or period) is twice the interval between samples, thus 0.5 cycle/sample. For example, audio CDs have a sampling rate of 44100 samples/second. At 0.5 cycle/sample, the corresponding Nyquist frequency is 22050 cycles/second (Hz). Conversely, the Nyquist rate for sampling a 22050 Hz signal is 44100 samples/second.

When the highest frequency (bandwidth) of a signal is less than the Nyquist frequency of the sampler, the resulting discrete-time sequence is said to be free of the distortion known as aliasing, and the corresponding sample rate is said to be above the Nyquist rate for that particular signal.

In a typical application of sampling, one first chooses the highest frequency to be preserved and recreated, based on the expected content (voice, music, etc.) and desired fidelity. Then one inserts an anti-aliasing filter ahead of the sampler. Its job is to attenuate the frequencies above that limit. Finally, based on the characteristics of the filter, one chooses a sample rate (and corresponding Nyquist frequency) that will provide an acceptably small amount of aliasing. In applications where the sample rate is pre-determined (such as the CD rate), the filter is chosen based on the Nyquist frequency, rather than vice versa.

🔗 Apple Inc. 🔗 Computing 🔗 Microsoft Windows 🔗 Microsoft Windows/Computing 🔗 Computing/Software 🔗 Software 🔗 Software/Computing 🔗 Microsoft 🔗 Microsoft/Microsoft Windows

Microsoft Works is a discontinued productivity software suite developed by Microsoft and sold from 1987 to 2009. Its core functionality included a word processor, a spreadsheet and a database management system. Later versions had a calendar application and a dictionary while older releases included a terminal emulator. Works was available as a standalone program, and as part of a namesake home productivity suite. Because of its low cost ($40 retail, or as low as $2 OEM), companies frequently pre-installed Works on their low-cost machines. Works was smaller, less expensive, and had fewer features than Microsoft Office and other major office suites available at the time.

Mainstream support for the final standalone and suite release ended on October 9, 2012 and January 8, 2013, respectively.

🔗 United States 🔗 Terrorism 🔗 Socialism 🔗 Michigan 🔗 Chicago

The Weather Underground Organization (WUO), commonly known as the Weather Underground, was a radical left militant organization active in the late 1960s and 1970s, founded on the Ann Arbor campus of the University of Michigan. It was originally called the Weathermen. The WUO organized in 1969 as a faction of Students for a Democratic Society (SDS) largely composed of the national office leadership of SDS and their supporters. Beginning in 1974, the organization's express political goal was to create a revolutionary party to overthrow American imperialism.

The FBI described the WUO as a domestic terrorist group, with revolutionary positions characterized by black power and opposition to the Vietnam War. The WUO took part in domestic attacks such as the jailbreak of Timothy Leary in 1970. The "Days of Rage" was the WUO's first riot in October 1969 in Chicago, timed to coincide with the trial of the Chicago Seven. In 1970, the group issued a "Declaration of a State of War" against the United States government under the name "Weather Underground Organization".

In the 1970s, the WUO conducted a bombing campaign targeting government buildings and several banks. Some attacks were preceded by evacuation warnings, along with threats identifying the particular matter that the attack was intended to protest. Three members of the group were killed in an accidental Greenwich Village townhouse explosion, but none were killed in any of the bombings. The WUO communiqué issued in connection with the bombing of the United States Capitol on March 1, 1971 indicated that it was "in protest of the U.S. invasion of Laos". The WUO asserted that its May 19, 1972 bombing of the Pentagon was "in retaliation for the U.S. bombing raid in Hanoi". The WUO announced that its January 29, 1975 bombing of the United States Department of State building was "in response to the escalation in Vietnam".

The WUO began to disintegrate after the United States reached a peace accord in Vietnam in 1973, and it was defunct by 1977.

The group took its name from Bob Dylan's lyric, "You don't need a weatherman to know which way the wind blows", from the song "Subterranean Homesick Blues" (1965). That Dylan line was also the title of a position paper distributed at an SDS convention in Chicago on June 18, 1969. This founding document called for a "White fighting force" to be allied with the "Black Liberation Movement" and other radical movements to achieve "the destruction of U.S. imperialism and form a classless communist world".

🔗 Electronics

Wire wrap was invented to wire telephone crossbar switches, and later adapted to construct electronic circuit boards. Electronic components mounted on an insulating board are interconnected by lengths of insulated wire run between their terminals, with the connections made by wrapping several turns of uninsulated sections of the wire around a component lead or a socket pin.

Wires can be wrapped by hand or by machine, and can be hand-modified afterwards. It was popular for large-scale manufacturing in the 1960s and early 1970s, and continues today to be used for short runs and prototypes. The method eliminates the design and fabrication of a printed circuit board. Wire wrapping is unusual among other prototyping technologies since it allows for complex assemblies to be produced by automated equipment, but then easily repaired or modified by hand.

Wire wrap construction can produce assemblies which are more reliable than printed circuits: connections are less prone to fail due to vibration or physical stresses on the base board, and the lack of solder precludes soldering faults such as corrosion, cold joints and dry joints. The connections themselves are firmer and have lower electrical resistance due to cold welding of the wire to the terminal post at the corners.

Wire wrap was used for assembly of high frequency prototypes and small production runs, including gigahertz microwave circuits and supercomputers. It is unique among automated prototyping techniques in that wire lengths can be exactly controlled, and twisted pairs or magnetically shielded twisted quads can be routed together.

Wire wrap construction became popular around 1960 in circuit board manufacturing, and use has now sharply declined. Surface-mount technology has made the technique much less useful than in previous decades. Solder-less breadboards and the decreasing cost of professionally made PCBs have nearly eliminated this technology.

NAR 2 (Serbian Nastavni Računar 2, en. Educational Computer 2) is a theoretical model of a 32-bit word computer created by Faculty of Mathematics of University of Belgrade professor Nedeljko Parezanović as an enhancement to its predecessor, NAR 1. It was used for Assembly language and Computer architecture courses. The word "nar" means Pomegranate in Serbian. Many NAR 2 simulators have been created — for instance, one was named "Šljiva" (en. plum) as that fruit grows in Serbia, while "nar" does not.