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🔗 Mathematics

Bellard's formula is used to calculate the nth digit of π in base 16.

Bellard's formula was discovered by Fabrice Bellard in 1997. It is about 43% faster than the Bailey–Borwein–Plouffe formula (discovered in 1995). It has been used in PiHex, the now-completed distributed computing project.

One important application is verifying computations of all digits of pi performed by other means. Rather than having to compute all of the digits twice by two separate algorithms to ensure that a computation is correct, the final digits of a very long all-digits computation can be verified by the much faster Bellard's formula.

Formula:

${\displaystyle {\begin{aligned}\pi ={\frac {1}{2^{6}}}\sum _{n=0}^{\infty }{\frac {(-1)^{n}}{2^{10n}}}\,\left(-{\frac {2^{5}}{4n+1}}\right.&{}-{\frac {1}{4n+3}}+{\frac {2^{8}}{10n+1}}-{\frac {2^{6}}{10n+3}}\left.{}-{\frac {2^{2}}{10n+5}}-{\frac {2^{2}}{10n+7}}+{\frac {1}{10n+9}}\right)\end{aligned}}}$

🔗 Companies 🔗 Computing 🔗 United Kingdom

Andrews & Arnold Ltd (also known as AAISP) is an Internet service provider based in Bracknell in the United Kingdom founded in 1997 and launched in 1998, primarily serving businesses and "technical" home users.

In 2009 the company was judged the best niche provider in the Thinkbroadband Customer Service Awards, based on customer ratings and again in 2010.

The company's owner, Adrian Kennard (RevK), stated in a blog post that as of October 2010 the company is "xkcd/806" compliant, referring to xkcd comic number 806. This means that technical support callers who say the code word "shibboleet" will be transferred to a technical support representative who knows at least two programming languages, and presumably can offer more useful advice than a standard tech support script.

Andrews & Arnold provides IPv6 to all customers, for no additional charge.

Andrews & Arnold provides optional bonded multiple-link internet access. This allows multiple links to be used together to vastly increase speed and reliability. Special routers distribute individual IP packets between the available links in such a way that even one single download or upload operation will benefit fully from multiple speed, and it is not necessary to have several users, several running programs or computers to gain the speed benefit. Links can be of different types, each needs only to be a pipe that can carry IP packets. Multiple links can either be used together all the time, or some can be brought up as a back up if other links fail, so-called 'failover', or a combination of the two approaches can be set up.

Andrews & Arnold are strong advocates of not censoring Internet connections. Adrian Kennard has several blog posts discussing why Internet censorship as discussed in the UK is not workable, providing background for AAISP's decision.

🔗 Biography 🔗 Psychology 🔗 Biography/science and academia

Edwin Ray Guthrie (; January 9, 1886 in Lincoln, Nebraska – April 23, 1959 in Seattle, Washington) was a behavioral psychologist. He first worked as a mathematics teacher, and philosopher, but switched to psychology when he was 33. He spent most of his career at the University of Washington, where he became full professor and then emeritus professor in psychology.

Guthrie is best known for his theory that all learning was based on a stimulus–response association. This was variously described as one trial theory, non-reinforcement, and contiguity learning. The theory was:

"A combination of stimuli which has accompanied a movement will on its recurrence tend to be followed by that movement".

One word that his coworkers and students used to describe Guthrie and his theories was "simple", and perhaps he did prefer to use simple terms to illustrate complex ideas. However, "It is undoubtedly true that many reviews of Guthrie in the literature have mistaken incompleteness for simplicity".

His simple nature carried into his teachings where he took great pride in working with and teaching students.

🔗 United States/U.S. Government 🔗 United States

Project COLDFEET was a 1962 Central Intelligence Agency (CIA) operation to extract intelligence from an abandoned Soviet Arctic drifting ice station. Due to the nature of its abandonment as the result of unstable ice, the retrieval of the operatives used the Fulton surface-to-air recovery system.

🔗 Politics 🔗 Psychology 🔗 Sociology

A collective action problem or social dilemma is a situation in which all individuals would be better off cooperating but fail to do so because of conflicting interests between individuals that discourage joint action. The collective action problem has been addressed in political philosophy for centuries, but was most clearly established in 1965 in Mancur Olson's The Logic of Collective Action.

Problems arise when too many group members choose to pursue individual profit and immediate satisfaction rather than behave in the group's best long-term interests. Social dilemmas can take many forms and are studied across disciplines such as psychology, economics, and political science. Examples of phenomena that can be explained using social dilemmas include resource depletion and low voter turnout. The collective action problem can be understood through the analysis of game theory and the free-rider problem, which results from the provision of public goods. Additionally, the collective problem can be applied to numerous public policy concerns that countries across the world currently face.

🔗 United States 🔗 Internet 🔗 Law 🔗 Freedom of speech 🔗 Law Enforcement 🔗 United States/FBI

A warrant canary is a method by which a communications service provider aims to inform its users that the provider has been served with a government subpoena despite legal prohibitions on revealing the existence of the subpoena. The warrant canary typically informs users that there has not been a court-issued subpoena as of a particular date. If the canary is not updated for the period specified by the host or if the warning is removed, users are to assume that the host has been served with such a subpoena. The intention is to allow the provider to warn users of the existence of a subpoena passively, without technically violating the court order not to do so.

Some subpoenas, such as those covered under 18 U.S.C. §2709(c) of the USA Patriot Act, provide criminal penalties for disclosing the existence of the subpoena to any third party, including the service provider's users.

National Security Letters (NSL) originated in the 1986 Electronic Communications Privacy Act and originally targeted those suspected of being agents of a foreign power. Targeting agents of a foreign power was revised in 2001 under the Patriot Act to allow NSLs to target those who may have information deemed relevant to both counterintelligence activities directed against the United States and terrorism. The idea of using negative pronouncements to thwart the nondisclosure requirements of court orders and served secret warrants was first proposed by Steven Schear on the cypherpunks mailing list, mainly to uncover targeted individuals at ISPs. It was also suggested for and used by public libraries in 2002 in response to the USA Patriot Act, which could have forced librarians to disclose the circulation history of library patrons.

🔗 United States 🔗 Biography 🔗 Children's literature 🔗 Chicago 🔗 Biography/Actors and Filmmakers

Alan Wolf Arkin (March 26, 1934 – June 29, 2023) was an American actor, director, and screenwriter best known for his performances on stage and screen. Throughout his career spanning eight decades, he received various accolades, including an Academy Award, two Screen Actors Guild Awards, a British Academy Film Award, a Golden Globe Award, and a Tony Award.

Arkin began his career on the Broadway stage, starring in Enter Laughing in 1963 for which he won the Tony Award for Best Featured Actor in a Play, and the comedic play Luv (1964). For his work directing The Sunshine Boys, he was nominated for the Tony Award for Best Direction of a Play in 1973. He gained stardom acting in The Russians Are Coming, the Russians Are Coming (1966), Wait Until Dark (1967), The Heart Is a Lonely Hunter (1968), Popi (1969), Catch-22 (1970), The In-Laws (1979), Edward Scissorhands (1990), Glengarry Glen Ross (1992), Grosse Point Blank (1997), Thirteen Conversations About One Thing (2001), Sunshine Cleaning (2007), Get Smart (2008), and Argo (2012). For his performance in Little Miss Sunshine, he won the Academy Award for Best Supporting Actor, and BAFTA Award for Best Actor in a Supporting Role.

He was also known for his roles on television including his performances as Leon Felhendler in Escape from Sobibor (1987), and as Harry Rowen in The Pentagon Papers (2003) which he earned Primetime Emmy Award for Outstanding Lead Actor in a Limited or Series or Movie nominations. From 2015 to 2016 he voiced J.D. Salinger in the Netflix animated series BoJack Horseman. From 2018 to 2019 he starred in the Netflix comedy series The Kominsky Method, earning two consecutive Primetime Emmy Award for Outstanding Supporting Actor in a Comedy Series nominations.

🔗 China 🔗 Ethnic groups 🔗 Gender Studies

The Mosuo (Chinese: 摩梭; pinyin: Mósuō) are a small ethnic group living in Yunnan and Sichuan provinces in China, close to the border with Tibet. Dubbed the 'Kingdom of Women' by the Chinese, the Mosuo population of about 50,000 live near Lugu Lake in the Tibetan Himalayas 27°42′35.30″N 100°47′4.04″E.

Scholars use diverse terms and spellings to designate the Mosuo culture. Most prefer 'Mosuo' some spell it 'Moso', while a minority use neither term, but refer to them as the Na people.

The Mosuo people are known as the 'Kingdom of Women' because the Na are a matrilineal society: heterosexual activity occurs only by mutual consent and mostly through the custom of the secret nocturnal 'visit'; men and women are free to have multiple partners, and to initiate or break off relationships when they please.

🔗 United States 🔗 Spaceflight 🔗 United States/Military history - U.S. military history 🔗 Physics

Project Longshot was a conceptual interstellar spacecraft design. It would have been an unmanned probe, intended to fly to and enter orbit around Alpha Centauri B powered by nuclear pulse propulsion.

🔗 Psychology 🔗 Gender Studies

Wife acceptance factor, wife approval factor, or wife appeal factor (WAF) is an assessment of design elements that either increase or diminish the likelihood a wife will approve the purchase of expensive consumer electronics products such as high-fidelity loudspeakers, home theater systems and personal computers. Stylish, compact forms and appealing colors are commonly considered to have a high WAF. The term is a tongue-in-cheek play on electronics jargon such as "form factor" and "power factor" and derives from the idea that men are predisposed to appreciate gadgetry and performance criteria whereas women must be wooed by visual and aesthetic factors.