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🔗 Computing 🔗 Computing/Computer Security 🔗 Computing/Networking

In computer networking, port knocking is a method of externally opening ports on a firewall by generating a connection attempt on a set of prespecified closed ports. Once a correct sequence of connection attempts is received, the firewall rules are dynamically modified to allow the host which sent the connection attempts to connect over specific port(s). A variant called single packet authorization (SPA) exists, where only a single "knock" is needed, consisting of an encrypted packet.

The primary purpose of port knocking is to prevent an attacker from scanning a system for potentially exploitable services by doing a port scan, because unless the attacker sends the correct knock sequence, the protected ports will appear closed.

🔗 United States 🔗 California 🔗 Law Enforcement 🔗 California/Los Angeles area 🔗 Crime and Criminal Biography 🔗 Crime and Criminal Biography/Organized crime

Since the 1970's, several deputies of the Los Angeles County Sheriff's Department have formed gangs in which membership is exclusive to certain sheriff's deputies, often along ethnic lines, and requires certain acts, such as police violence (particularly against people of color), in order to be initiated into said gang. Members are often tattooed and are expected to maintain the blue wall of silence (i.e. not snitch or report misconduct on or about other officers), fabricate evidence, engage in police corruption, and engage in criminal activity such as vandalism and homicide, among other things. Historically, almost all instances of deputy gang violence has either been ignored by the Los Angeles County District Attorney's Office or the office has stood by the members of the deputy gangs, alongside the tolerance or assistance of the county sheriff. Although not unique to the Los Angeles County Sheriff's Department, it suffers from the most prolific case of the existence of law enforcement gangs in the state.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Intelligence 🔗 Military history/Cold War 🔗 Military history/Australia, New Zealand and South Pacific military history 🔗 Military history/Canadian military history 🔗 Military history/European military history 🔗 Military history/British military history

The Five Eyes (FVEY) is an anglophone intelligence alliance comprising Australia, Canada, New Zealand, the United Kingdom and the United States. These countries are parties to the multilateral UKUSA Agreement, a treaty for joint cooperation in signals intelligence.

The origins of the FVEY can be traced back to the post–World War II period, when the Atlantic Charter was issued by the Allies to lay out their goals for a post-war world. During the course of the Cold War, the ECHELON surveillance system was initially developed by the FVEY to monitor the communications of the former Soviet Union and the Eastern Bloc, although it is now used to monitor billions of private communications worldwide.

In the late 1990s, the existence of ECHELON was disclosed to the public, triggering a major debate in the European Parliament and, to a lesser extent, the United States Congress. As part of efforts in the ongoing War on Terror since 2001, the FVEY further expanded their surveillance capabilities, with much emphasis placed on monitoring the World Wide Web. The former NSA contractor Edward Snowden described the Five Eyes as a "supra-national intelligence organisation that does not answer to the known laws of its own countries". Documents leaked by Snowden in 2013 revealed that the FVEY has been spying on one another's citizens and sharing the collected information with each other in order to circumvent restrictive domestic regulations on surveillance of citizens.

In spite of continued controversy over its methods, the Five Eyes relationship remains one of the most comprehensive known espionage alliances in history.

Since processed intelligence is gathered from multiple sources, the intelligence shared is not restricted to signals intelligence (SIGINT) and often involves defence intelligence as well as human intelligence (HUMINT) and geospatial intelligence (GEOINT). The following table provides an overview of most of the FVEY agencies involved in such forms of data sharing.

🔗 Culture

Bohm Dialogue (also known as Bohmian Dialogue or "Dialogue in the Spirit of David Bohm") is a freely flowing group conversation in which participants attempt to reach a common understanding, experiencing everyone's point of view fully, equally and nonjudgementally. This can lead to new and deeper understanding. The purpose is to solve the communication crises that face society, and indeed the whole of human nature and consciousness. It utilizes a theoretical understanding of the way thoughts relate to universal reality. It is named after physicist David Bohm who originally proposed this form of dialogue.

🔗 Video games 🔗 Film 🔗 Television 🔗 Science Fiction

Black Mirror: Bandersnatch is a 2018 interactive film in the science fiction anthology series Black Mirror. It was written by series creator Charlie Brooker and directed by David Slade. Netflix released the standalone film on 28 December 2018.

In Bandersnatch, viewers make decisions for the main character, the young programmer Stefan Butler (Fionn Whitehead), who is adapting a fantasy choose-your-own-adventure novel into a video game in 1984. Other characters include Mohan Thakur (Asim Chaudhry) and Colin Ritman (Will Poulter), both of whom work at a video game company, Butler's father, Peter (Craig Parkinson), and Butler's therapist, Dr. Haynes (Alice Lowe). The film is based on a planned Imagine Software video game of the same name which went unreleased after the company filed for bankruptcy. It also alludes to Lewis Carroll's own works that feature the bandersnatch creature. A piece of science fiction and horror, Bandersnatch incorporates meta-commentary and rumination on free will.

Brooker and executive producer Annabel Jones were approached by Netflix about making an interactive film in May 2017, during which time Netflix had several interactive projects for children underway. Difficulty in writing the highly non-linear script led to the creation of a bespoke program called Branch Manager for Netflix; the unique nature of the content required adaptations in the platform's use of cache memory. Filming and production took longer than for typical Black Mirror episodes, resulting in the show's fifth series being delayed. A quickly-deleted tweet from a Netflix account about the release of Bandersnatch led to widespread media speculation throughout December which Netflix declined to comment on. The trailer for Bandersnatch was released on 27 December 2018, a day before the film was released. Critical reception for the film was generally positive, though some found the interactive nature to be too gimmicky for a proper Black Mirror narrative. In 2019, the episode won two Emmy Awards, including the Outstanding Television Movie award.

🔗 History 🔗 Lists 🔗 Business

This is a list of obsolete occupations. To be included in this list an occupation must be completely, or to a great extent, obsolete. For example, there are still a few lamplighters retained for ceremonial or tourist purposes, but in the main the occupation is now obsolete. Similarly, there are still some manual switchboard operators and elevator operators which are required for historic equipment or security reasons, but these are now considered to be obsolete occupations. Occupations which appear to be obsolete in industrialized countries may still be carried out commercially in other parts of the world, for example charcoal burner.

To be included in this list an obsolete occupation should in the past have employed significant numbers of workers (hundreds or thousands as evidenced by, for example, census data). Some rare occupations are included in this list, but only if they have notable practitioners, for example alchemist or phrenologist.

Terms which describe groups of people carrying out a variety of roles, but which are not specific occupations, are excluded from this list even if they are obsolete, for example conquistador or retinue. Terms describing positions which have a modern equivalent, and are thus not obsolete occupations, are excluded from this list, for example a dragoman would now be termed a diplomat; similarly a cunning woman would now be termed a practitioner of folk medicine. Terms describing a state of being rather than an occupation are excluded, for example castrato. Specialist terms for an occupation, even if they are obsolete, are excluded, for example the numerous historic terms for cavalry and courtesan. Foreign language terms for existing occupations are excluded, for example korobeinik or Laukkuryssä which are types of peddler. All types of forced labour, such as slavery and penal labour are excluded from this list as they are not paid occupations.

Only occupations which are notable, well-defined, and adequately documented in secondary sources are included in this list.

🔗 Russia 🔗 Russia/technology and engineering in Russia 🔗 Russia/science and education in Russia 🔗 Geology

The Kola Superdeep Borehole (Russian: Кольская сверхглубокая скважина) is the result of a scientific drilling project of the Soviet Union in the Pechengsky District, on the Kola Peninsula. The project attempted to drill as deep as possible into the Earth's crust. Drilling began on 24 May 1970 using the Uralmash-4E, and later the Uralmash-15000 series drilling rig. Boreholes were drilled by branching from a central hole. The deepest, SG-3, reached 12,262 metres (40,230 ft; 7.619 mi) in 1989 and is the deepest artificial point on Earth. The borehole is 23 centimetres (9 in) in diameter.

In terms of true vertical depth, it is the deepest borehole in the world. For two decades it was also the world's longest borehole in terms of measured depth along the well bore, until it was surpassed in 2008 by the 12,289-metre-long (40,318 ft) Al Shaheen oil well in Qatar, and in 2011 by the 12,345-metre-long (40,502 ft) Sakhalin-I Odoptu OP-11 Well (offshore from the Russian island of Sakhalin).

🔗 Aviation 🔗 Aviation/aircraft

A propfan, also called an open rotor engine, or unducted fan, is a type of aircraft engine related in concept to both the turboprop and turbofan, but distinct from both. The design is intended to offer the speed and performance of a turbofan, with the fuel economy of a turboprop. A propfan is typically designed with a large number of short, highly twisted blades, similar to a turbofan's bypass compressor (the fan itself). For this reason, the propfan has been variously described as an "unducted fan" or an "ultra-high-bypass (UHB) turbofan."

🔗 Computing

Constraint programming (CP) is a paradigm for solving combinatorial problems that draws on a wide range of techniques from artificial intelligence, computer science, and operations research. In constraint programming, users declaratively state the constraints on the feasible solutions for a set of decision variables. Constraints differ from the common primitives of imperative programming languages in that they do not specify a step or sequence of steps to execute, but rather the properties of a solution to be found. In addition to constraints, users also need to specify a method to solve these constraints. This typically draws upon standard methods like chronological backtracking and constraint propagation, but may use customized code like a problem specific branching heuristic.

Constraint programming takes its root from and can be expressed in the form of constraint logic programming, which embeds constraints into a logic program. This variant of logic programming is due to Jaffar and Lassez, who extended in 1987 a specific class of constraints that were introduced in Prolog II. The first implementations of constraint logic programming were Prolog III, CLP(R), and CHIP.

Instead of logic programming, constraints can be mixed with functional programming, term rewriting, and imperative languages. Programming languages with built-in support for constraints include Oz (functional programming) and Kaleidoscope (imperative programming). Mostly, constraints are implemented in imperative languages via constraint solving toolkits, which are separate libraries for an existing imperative language.

🔗 Books 🔗 Psychology 🔗 Japan

The Mariko Aoki phenomenon (青木まりこ現象, Aoki Mariko genshō) is a Japanese expression referring to an urge to defecate that is suddenly felt after entering bookstores. The phenomenon's name derives from the name of the woman who mentioned the phenomenon in a magazine article in 1985. According to Japanese social psychologist Shozo Shibuya, the specific causes that trigger a defecation urge in bookstores are not yet clearly understood (as of 2014). There are also some who are skeptical about whether such a peculiar phenomenon really exists at all, and it is sometimes discussed as one type of urban myth.

The series of processes through which being in a bookstore leads to an awareness of a defecation urge is something that cannot be explained from a medical perspective as a single pathological concept, at least at present. According to a number of discussions on the topic, even if it can be sufficiently found that this phenomenon actually exists, it is a concept that would be difficult to be deemed a specific pathological entity (such as a "Mariko Aoki disease", for example). On the other hand, it is also a fact that a considerable number of the intellectuals (particularly clinicians) who discuss this phenomenon have adopted existing medical terminology such as from diagnostics and pathology. Borrowing from this approach, this article also uses expressions from existing medical terminology for convenience.