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🔗 Telecommunications

Signaling System No. 7 (SS7) is a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN). The protocol also performs number translation, local number portability, prepaid billing, Short Message Service (SMS), and other services.

In North America SS7 is often referred to as Common Channel Signaling System 7 (CCSS7). In the United Kingdom, it is called C7 (CCITT number 7), number 7 and Common Channel Interoffice Signaling 7 (CCIS7). In Germany, it is often called Zentraler Zeichengabekanal Nummer 7 (ZZK-7).

The SS7 protocol is defined for international use by the Q.700-series recommendations of 1988 by the ITU-T. Of the many national variants of the SS7 protocols, most are based on variants standardized by the American National Standards Institute (ANSI) and the European Telecommunications Standards Institute (ETSI). National variants with striking characteristics are the Chinese and Japanese Telecommunication Technology Committee (TTC) national variants.

The Internet Engineering Task Force (IETF) has defined the SIGTRAN protocol suite that implements levels 2, 3, and 4 protocols compatible with SS7. Sometimes also called Pseudo SS7, it is layered on the Stream Control Transmission Protocol (SCTP) transport mechanism for use on Internet Protocol networks, such as the Internet.

🔗 Law 🔗 Lists

A 999-year lease, under historic common law, is an essentially permanent lease of property. The lease locations are mainly in Britain, its former colonies, and the Commonwealth.

A former colony, the Republic of Mauritius (The Raphael Fishing Company Ltd v. The State of Mauritius & Anor (Mauritius) [2008] UKPC 43 (30 July 2008)) established legal precedent on 30 July 2008 in respect of a 'permanent lease' on St. Brandon.

🔗 Business

Topgrading is a corporate hiring and interviewing methodology that is intended to identify preferred candidates for a particular position. In the methodology, prospective employees undergo a 12-step process that includes extensive interviews, the creation of detailed job scorecards, research into job history, coaching, and more. After being interviewed and reference-checked, job candidates are grouped into one of three categories: A Players, B Players, or C Players. A Players have the most potential for high performance in their role while B and C Players may require more work to be successful. The methodology has been used by major corporations and organizations like General Electric, Lincoln Financial, Honeywell, Barclays, and the American Heart Association.

🔗 Mathematics

Von Neumann's elephant is a problem in recreational mathematics, consisting of constructing a planar curve in the shape of an elephant from only four fixed parameters. It originated from a discussion between physicists John von Neumann and Enrico Fermi.

🔗 Novels 🔗 Science Fiction 🔗 Transhumanism

A Fire Upon the Deep is a 1992 science fiction novel by American writer Vernor Vinge. It is a space opera involving superhuman intelligences, aliens, variable physics, space battles, love, betrayal, genocide, and a communication medium resembling Usenet. A Fire Upon the Deep won the Hugo Award in 1993, sharing it with Doomsday Book by Connie Willis.

Besides the normal print book editions, the novel was also included on a CD-ROM sold by ClariNet Communications along with the other nominees for the 1993 Hugo awards. The CD-ROM edition included numerous annotations by Vinge on his thoughts and intentions about different parts of the book, and was later released as a standalone e-book (no longer available).

🔗 United States/U.S. Government 🔗 United States 🔗 Mass surveillance 🔗 Espionage 🔗 Computing 🔗 Australia 🔗 New Zealand 🔗 United Kingdom 🔗 Computing/Computer Security 🔗 Computing/Networking

XKeyscore (XKEYSCORE or XKS) is a secret computer system used by the United States National Security Agency (NSA) for searching and analyzing global Internet data, which it collects in real time. The NSA has shared XKeyscore with other intelligence agencies, including the Australian Signals Directorate, Canada's Communications Security Establishment, New Zealand's Government Communications Security Bureau, Britain's Government Communications Headquarters, Japan's Defense Intelligence Headquarters, and Germany's Bundesnachrichtendienst.

In July 2013, Edward Snowden publicly revealed the program's purpose and use by the NSA in The Sydney Morning Herald and O Globo newspapers. The code name was already public knowledge because it was mentioned in earlier articles, and, like many other code names, it appears in job postings and online résumés of employees.

On July 3, 2014, German public broadcaster Norddeutscher Rundfunk, a member of ARD, published excerpts of XKeyscore's source code. A team of experts analyzed the source code.

🔗 California 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/World War II 🔗 Paranormal 🔗 California/Southern California

The Battle of Los Angeles, also known as the Great Los Angeles Air Raid, is the name given by contemporary sources to a rumored attack on the mainland United States by Imperial Japan and the subsequent anti-aircraft artillery barrage which took place from late 24 February to early 25 February 1942, over Los Angeles, California. The incident occurred less than three months after the U.S. entered World War II in response to the Imperial Japanese Navy's surprise attack on Pearl Harbor, and one day after the bombardment of Ellwood near Santa Barbara on 23 February. Initially, the target of the aerial barrage was thought to be an attacking force from Japan, but speaking at a press conference shortly afterward, Secretary of the Navy Frank Knox called the purported attack a "false alarm". Newspapers of the time published a number of reports and speculations of a cover-up.

When documenting the incident in 1949, the United States Coast Artillery Association identified a meteorological balloon sent aloft at 1:00 am as having "started all the shooting" and concluded that "once the firing started, imagination created all kinds of targets in the sky and everyone joined in". In 1983, the U.S. Office of Air Force History attributed the event to a case of "war nerves" triggered by a lost weather balloon and exacerbated by stray flares and shell bursts from adjoining batteries.

🔗 Film 🔗 Film/American cinema 🔗 Film/Documentary films

Werner Herzog Eats His Shoe is a short documentary film directed by Les Blank in 1980 which depicts director Werner Herzog living up to his promise that he would eat his shoe if Errol Morris ever completed the film Gates of Heaven. The film includes clips from both Gates of Heaven and Herzog's 1970 feature Even Dwarfs Started Small. Comic song "Old Whisky Shoes", played by the Walt Solek Band, is the signature tune over the opening and closing credits.

Filmed in April 1979, the film features Herzog cooking his shoes (the ones he claims to have been wearing when he made the bet) at the Berkeley, California restaurant Chez Panisse, with the help of chef Alice Waters. (The shoes were boiled with garlic, herbs, and stock for 5 hours.) He is later shown eating one of the shoes before an audience at the premiere of Gates of Heaven at the nearby UC Theater. He did not eat the sole of the shoe, however, explaining that one does not eat the bones of the chicken.

Morris is not shown in the film, and Herzog, Morris, and others have told different stories of the nature of the bet, disagreeing as to whether it was serious, flippant, or an after-the-fact publicity stunt.

Blank went on to direct Burden of Dreams (1982), a feature-length documentary about Herzog and the making of Fitzcarraldo. Werner Herzog Eats His Shoe is included as an extra on The Criterion Collection edition of the Burden of Dreams DVD. It is also included as an extra in the Criterion Collection edition of the Gates of Heaven Blu-ray disc.

When Chez Panisse celebrated its 40th anniversary, a replica of the shoe was created, boiled, and eaten as part of the public anniversary celebration.

The Academy Film Archive preserved Werner Herzog Eats His Shoe in 1999.

🔗 Philosophy 🔗 Philosophy/Logic

Buridan's ass is an illustration of a paradox in philosophy in the conception of free will. It refers to a hypothetical situation wherein an ass that is equally hungry and thirsty is placed precisely midway between a stack of hay and a pail of water. Since the paradox assumes the ass will always go to whichever is closer, it dies of both hunger and thirst since it cannot make any rational decision between the hay and water. A common variant of the paradox substitutes two identical piles of hay for the hay and water; the ass, unable to choose between the two, dies of hunger.

The paradox is named after the 14th-century French philosopher Jean Buridan, whose philosophy of moral determinism it satirizes. Although the illustration is named after Buridan, philosophers have discussed the concept before him, notably Aristotle, who used the example of a man equally hungry and thirsty, and Al-Ghazali, who used a man faced with the choice of equally good dates.

A version of this situation appears as metastability in digital electronics, when a circuit must decide between two states based on an input that is in itself undefined (neither zero nor one). Metastability becomes a problem if the circuit spends more time than it should in this "undecided" state, which is usually set by the speed of the clock the system is using.