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🔗 Musical Instruments 🔗 Electronic music

The theremin (; originally known as the ætherphone/etherphone, thereminophone or termenvox/thereminvox) is an electronic musical instrument controlled without physical contact by the thereminist (performer). It is named after its inventor, Léon Theremin, who patented the device in 1928.

The instrument's controlling section usually consists of two metal antennas that sense the relative position of the thereminist's hands and control oscillators for frequency with one hand, and amplitude (volume) with the other. The electric signals from the theremin are amplified and sent to a loudspeaker.

The sound of the instrument is often associated with eerie situations. Thus, the theremin has been used in movie soundtracks such as Miklós Rózsa's Spellbound and The Lost Weekend, Bernard Herrmann's The Day the Earth Stood Still, and Justin Hurwitz's First Man, as well as in theme songs for television shows such as the ITV drama Midsomer Murders. The theremin is also used in concert music (especially avant-garde and 20th- and 21st-century new music), and in popular music genres such as rock.

🔗 Statistics

In statistics, a Pólya urn model (also known as a Pólya urn scheme or simply as Pólya's urn), named after George Pólya, is a type of statistical model used as an idealized mental exercise framework, unifying many treatments.

In an urn model, objects of real interest (such as atoms, people, cars, etc.) are represented as colored balls in an urn or other container. In the basic Pólya urn model, the urn contains x white and y black balls; one ball is drawn randomly from the urn and its color observed; it is then returned in the urn, and an additional ball of the same color is added to the urn, and the selection process is repeated. Questions of interest are the evolution of the urn population and the sequence of colors of the balls drawn out.

This endows the urn with a self-reinforcing property sometimes expressed as the rich get richer.

Note that in some sense, the Pólya urn model is the "opposite" of the model of sampling without replacement, where every time a particular value is observed, it is less likely to be observed again, whereas in a Pólya urn model, an observed value is more likely to be observed again. In both of these models, the act of measurement has an effect on the outcome of future measurements. (For comparison, when sampling with replacement, observation of a particular value has no effect on how likely it is to observe that value again.) In a Pólya urn model, successive acts of measurement over time have less and less effect on future measurements, whereas in sampling without replacement, the opposite is true: After a certain number of measurements of a particular value, that value will never be seen again.

One of the reasons for interest in this particular rather elaborate urn model (i.e. with duplication and then replacement of each ball drawn) is that it provides an example in which the count (initially x black and y white) of balls in the urn is not concealed, which is able to approximate the correct updating of subjective probabilities appropriate to a different case in which the original urn content is concealed while ordinary sampling with replacement is conducted (without the Pólya ball-duplication). Because of the simple "sampling with replacement" scheme in this second case, the urn content is now static, but this greater simplicity is compensated for by the assumption that the urn content is now unknown to an observer. A Bayesian analysis of the observer's uncertainty about the urn's initial content can be made, using a particular choice of (conjugate) prior distribution. Specifically, suppose that an observer knows that the urn contains only identical balls, each coloured either black or white, but he does not know the absolute number of balls present, nor the proportion that are of each colour. Suppose that he holds prior beliefs about these unknowns: for him the probability distribution of the urn content is well approximated by some prior distribution for the total number of balls in the urn, and a beta prior distribution with parameters (x,y) for the initial proportion of these which are black, this proportion being (for him) considered approximately independent of the total number. Then the process of outcomes of a succession of draws from the urn (with replacement but without the duplication) has approximately the same probability law as does the above Pólya scheme in which the actual urn content was not hidden from him. The approximation error here relates to the fact that an urn containing a known finite number m of balls of course cannot have an exactly beta-distributed unknown proportion of black balls, since the domain of possible values for that proportion are confined to being multiples of ${\displaystyle 1/m}$, rather than having the full freedom to assume any value in the continuous unit interval, as would an exactly beta distributed proportion. This slightly informal account is provided for reason of motivation, and can be made more mathematically precise.

This basic Pólya urn model has been enriched and generalized in many ways.

🔗 Board and table games

Mancala is a generic name for a family of two-player turn-based strategy board games played with small stones, beans, or seeds and rows of holes or pits in the earth, a board or other playing surface. The objective is usually to capture all or some set of the opponent's pieces.

Versions of the game date back to the 7th century and evidence suggests the game existed in ancient Egypt. It is among the oldest known games to still be widely played today

🔗 Economics 🔗 Law Enforcement

The iron law of prohibition is a term coined by Richard Cowan in 1986 which posits that as law enforcement becomes more intense, the potency of prohibited substances increases. Cowan put it this way: "the harder the enforcement, the harder the drugs."

This law is an application of the Alchian–Allen effect; Libertarian judge James P. Gray calls the law the "cardinal rule of prohibition", and notes that is a powerful argument for the legalization of drugs. It is based on the premise that when drugs or alcohol are prohibited, they will be produced in black markets in more concentrated and powerful forms, because these more potent forms offer better efficiency in the business model—they take up less space in storage, less weight in transportation, and they sell for more money. Economist Mark Thornton writes that the iron law of prohibition undermines the argument in favor of prohibition, because the higher potency forms are less safe for the consumer.

🔗 Television 🔗 Science Fiction 🔗 Television/British television 🔗 Television/ITC productions

The Prisoner is a 1967 British television series about an unnamed British intelligence agent who is abducted and imprisoned in a mysterious coastal village, where his captors designate him as Number Six and try to find out why he abruptly resigned from his job. Patrick McGoohan played the lead role as Number Six. The series was created by McGoohan with possible contributions from George Markstein. Episode plots have elements of science fiction, allegory, and psychological drama, as well as spy fiction. It was produced by Everyman Films for distribution by Lew Grade's ITC Entertainment.

A single series of 17 episodes was filmed between September 1966 and January 1968, with exterior location filming in Portmeirion, Wales. Interior scenes were filmed at MGM-British Studios in Borehamwood, north of London. The series was first broadcast in Canada beginning on 5 September 1967, in the UK on 29 September 1967, and in the US on 1 June 1968. Although the show was sold as a thriller in the mould of the previous series starring McGoohan, Danger Man, its combination of 1960s countercultural themes and surrealistic setting had a far-reaching influence on science fiction and fantasy TV programming, and on narrative popular culture in general. Since its initial screening, the series has developed a cult following.

A six-part TV miniseries remake aired on the US cable channel AMC in November 2009. In 2016, Big Finish Productions reinterpreted the series as an audio drama.

🔗 Biography 🔗 California 🔗 California/San Francisco Bay Area 🔗 Apple Inc. 🔗 Biography/science and academia 🔗 LGBT studies

Ronald Wayne (born May 17, 1934) is a retired American electronics industry businessman. He co-founded Apple Computer Company (now Apple Inc.) as a partnership with Steve Wozniak and Steve Jobs, providing administrative oversight and documentation for the new venture. Twelve days later, he sold his 10% share of the new company back to Jobs and Wozniak for US$800, and one year later accepted a final US$1,500 to forfeit any potential future claims against the newly legally incorporated Apple, totaling $2,300.

🔗 Arab world

The elephant clock was a medieval invention by Al-Jazari (1136–1206), an Arab engineer and inventor of various clocks. The device consisted of a weight powered water clock in the form of an Asian elephant. This horological technology was derived from earlier Indian clocks and Chinese clocks.

In China clock escapement mechanism was invented by the polymath and Buddhist monk Yi Xing as well as the hydraulic powered waterwheel and water clock in the mechanically-driven and rotated equatorial armillary sphere of the polymaths Zhang Heng and Ma Jun. The Elephant clock had some design differences compared to earlier Indian and Chinese clocks and the various elements of the clock are in the housing (howdah) on top of the elephant.

Al-Jazari upon finishing the development and construction of his Elephant clock wrote: "The elephant represents the Indian and African cultures, the two dragons represents Chinese culture, the phoenix represents Persian culture, the water work represents Greek culture, and the turban represents Islamic culture" signifying the multicultural mentality of the intellectual Al-Jazari.

In addition to its mechanical innovations, the clock itself is seen as an early example of multiculturalism represented in technology.

🔗 Companies 🔗 Apple Inc. 🔗 Business 🔗 Nevada

Braeburn Capital Inc. is an asset management company based in Reno, Nevada and a subsidiary of Apple Inc. Its offices are located at 6900 S. McCarran Boulevard in Reno.

🔗 Mathematics

A mathematical coincidence is said to occur when two expressions with no direct relationship show a near-equality which has no apparent theoretical explanation.

For example, there is a near-equality close to the round number 1000 between powers of 2 and powers of 10:

${\displaystyle 2^{10}=1024\approx 1000=10^{3}.}$

Some mathematical coincidences are used in engineering when one expression is taken as an approximation of another.

🔗 Occupational Safety and Health

Lock Out, Tag Out (LOTO), Lock Out, Tag Out, Try Out (LOTOTO) or lock and tag is a safety procedure used in industry and research settings to ensure that dangerous machines are properly shut off and not able to be started up again prior to the completion of maintenance or repair work. It requires that hazardous energy sources be "isolated and rendered inoperative" before work is started on the equipment in question. The isolated power sources are then locked and a tag is placed on the lock identifying the worker who placed it. The worker then holds the key for the lock, ensuring that only he or she can remove the lock and start the machine. This prevents accidental startup of a machine while it is in a hazardous state or while a worker is in direct contact with it.

Lockout-tagout is used across industries as a safe method of working on hazardous equipment and is mandated by law in some countries.