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🔗 Computing 🔗 Computing/Software

The Pick operating system (often called just "the Pick system" or simply "Pick") is a demand-paged, multiuser, virtual memory, time-sharing computer operating system based around a unique MultiValue database. Pick is used primarily for business data processing. It is named after one of its developers, Dick Pick.

The term "Pick system" has also come to be used as the general name of all operating environments which employ this multivalued database and have some implementation of Pick/BASIC and ENGLISH/Access queries. Although Pick started on a variety of minicomputers, the system and its various implementations eventually spread to a large assortment of microcomputers, personal computers and mainframe computers.

🔗 Computer Security 🔗 Computer Security/Computing

In computer security, a billion laughs attack is a type of denial-of-service (DoS) attack which is aimed at parsers of XML documents.

It is also referred to as an XML bomb or as an exponential entity expansion attack.

🔗 Biography 🔗 Mathematics 🔗 Biography/science and academia 🔗 History of Science 🔗 Switzerland 🔗 Genealogy

The Bernoulli family (German pronunciation: [bɛʁˈnʊli]) of Basel was a patrician family, notable for having produced eight mathematically gifted academics who, among them, contributed substantially to the development of mathematics and physics during the early modern period.

🔗 Computer science 🔗 Computer science/Computing

Lucid is a dataflow programming language designed to experiment with non-von Neumann programming models. It was designed by Bill Wadge and Ed Ashcroft and described in the 1985 book Lucid, the Dataflow Programming Language.

pLucid was the first interpreter for Lucid.

🔗 Mathematics

In geometric topology, the Clifford torus is the simplest and most symmetric flat embedding of the cartesian product of two circles S¹_a and S¹_b (in the same sense that the surface of a cylinder is "flat"). It is named after William Kingdon Clifford. It resides in R⁴, as opposed to in R³. To see why R⁴ is necessary, note that if S¹_a and S¹_b each exist in their own independent embedding spaces R²_a and R²_b, the resulting product space will be R⁴ rather than R³. The historically popular view that the cartesian product of two circles is an R³ torus in contrast requires the highly asymmetric application of a rotation operator to the second circle, since that circle will only have one independent axis z available to it after the first circle consumes x and y.

Stated another way, a torus embedded in R³ is an asymmetric reduced-dimension projection of the maximally symmetric Clifford torus embedded in R⁴. The relationship is similar to that of projecting the edges of a cube onto a sheet of paper. Such a projection creates a lower-dimensional image that accurately captures the connectivity of the cube edges, but also requires the arbitrary selection and removal of one of the three fully symmetric and interchangeable axes of the cube.

If S¹_a and S¹_b each has a radius of ${\displaystyle \textstyle {\sqrt {1/2}}}$, their Clifford torus product will fit perfectly within the unit 3-sphere S³, which is a 3-dimensional submanifold of R⁴. When mathematically convenient, the Clifford torus can be viewed as residing inside the complex coordinate space C², since C² is topologically equivalent to R⁴.

The Clifford torus is an example of a square torus, because it is isometric to a square with opposite sides identified. It is further known as a Euclidean 2-torus (the "2" is its topological dimension); figures drawn on it obey Euclidean geometry as if it were flat, whereas the surface of a common "doughnut"-shaped torus is positively curved on the outer rim and negatively curved on the inner. Although having a different geometry than the standard embedding of a torus in three-dimensional Euclidean space, the square torus can also be embedded into three-dimensional space, by the Nash embedding theorem; one possible embedding modifies the standard torus by a fractal set of ripples running in two perpendicular directions along the surface.

🔗 Disaster management 🔗 Medicine 🔗 China 🔗 Food and drink 🔗 Medicine/Toxicology 🔗 Taiwan

Gutter oil (Chinese: 地沟油; pinyin: dìgōu yóu, or 餿水油; sōushuǐ yóu) is oil which has been recycled from waste oil collected from sources such as restaurant fryers, grease traps, slaughterhouse waste and fatbergs.

Reprocessing of used cooking oil is often very rudimentary; techniques include filtration, boiling, refining, and the removal of some adulterants. It is then packaged and resold as a cheaper alternative to normal cooking oil. Another version of gutter oil uses discarded animal parts, animal fat and skins, internal organs, and expired or otherwise low-quality meat, which is then cooked in large vats in order to extract the oil. Used kitchen oil can be purchased for between $859 and $937 per ton, while the cleaned and refined product can sell for $1,560 per ton. Thus there is great economic incentive to produce and sell gutter oil.

It was estimated in 2011 that up to one in every ten lower-market restaurant meals consumed in China is prepared with recycled oil. As Feng Ping of the China Meat Research Center has said: "The illegal oil shows no difference in appearance and indicators after refining and purification because the law breakers are skillful at coping with the established standards."

Some street vendors and restaurants in China and Taiwan have illegally used recycled oil unfit for human consumption for the purposes of cooking food, leading to a crackdown against such establishments by the Chinese and Taiwanese governments.

Gutter oil is an acceptable raw ingredient for products that are not for human consumption, such as soap, rubber, bio-fuel, and cosmetics.

🔗 Mathematics 🔗 Physics 🔗 Systems 🔗 Systems/Dynamical systems

The Abelian sandpile model, also known as the Bak–Tang–Wiesenfeld model, was the first discovered example of a dynamical system displaying self-organized criticality. It was introduced by Per Bak, Chao Tang and Kurt Wiesenfeld in a 1987 paper.

The model is a cellular automaton. In its original formulation, each site on a finite grid has an associated value that corresponds to the slope of the pile. This slope builds up as "grains of sand" (or "chips") are randomly placed onto the pile, until the slope exceeds a specific threshold value at which time that site collapses transferring sand into the adjacent sites, increasing their slope. Bak, Tang, and Wiesenfeld considered process of successive random placement of sand grains on the grid; each such placement of sand at a particular site may have no effect, or it may cause a cascading reaction that will affect many sites.

The model has since been studied on the infinite lattice, on other (non-square) lattices, and on arbitrary graphs (including directed multigraphs). It is closely related to the dollar game, a variant of the chip-firing game introduced by Biggs.

🔗 Germany 🔗 Jewish history 🔗 Adoption, fostering, orphan care and displacement

The Kindertransport (German for "children's transport") was an organised rescue effort of children from Nazi-controlled territory that took place in 1938–1939 during the nine months prior to the outbreak of the Second World War. The United Kingdom took in nearly 10,000 children, most of them Jewish, from Germany, Austria, Czechoslovakia, Poland, and the Free City of Danzig. The children were placed in British foster homes, hostels, schools, and farms. Often they were the only members of their families who survived the Holocaust that was to come. The programme was supported, publicised, and encouraged by the British government, which waived the visa immigration requirements that were not within the ability of the British Jewish community to fulfil. The British government placed no numerical limit on the programme; it was the start of the Second World War that brought it to an end, by which time about 10,000 kindertransport children had been brought to the country.

Smaller numbers of children were taken in via the programme by the Netherlands, Belgium, France, Sweden, and Switzerland. The term "kindertransport" may also be applied to the rescue of mainly Jewish children from Nazi German territory to the Netherlands, Belgium, and France. An example is the 1,000 Chateau de La Hille children who went to Belgium. However, most often the term is restricted to the organised programme of the United Kingdom.

The Central British Fund for German Jewry (now World Jewish Relief) was established in 1933 to support in whatever way possible the needs of Jews in Germany and Austria.

In the United States, the Wagner–Rogers Bill was introduced in Congress, which would have increased the quota of immigrants by bringing to the U.S. a total of 20,000 refugee children, but it did not pass.

🔗 Law 🔗 Indonesia 🔗 Primates 🔗 Animal rights 🔗 Photography

The monkey selfie copyright dispute is a series of disputes about the copyright status of selfies taken by Celebes crested macaques using equipment belonging to the British nature photographer David Slater. The disputes involve Wikimedia Commons and the blog Techdirt, which have hosted the images following their publication in newspapers in July 2011 over Slater's objections that he holds the copyright, and People for the Ethical Treatment of Animals (PETA), who have argued that the macaque should be assigned the copyright.

Slater has argued that he has a valid copyright claim, as he engineered the situation that resulted in the pictures by travelling to Indonesia, befriending a group of wild macaques, and setting up his camera equipment in such a way that a "selfie" picture might come about. The Wikimedia Foundation's 2014 refusal to remove the pictures from its Wikimedia Commons image library was based on the understanding that copyright is held by the creator, that a non-human creator (not being a legal person) cannot hold copyright, and that the images are thus in the public domain.

Slater stated in August 2014 that, as a result of the pictures being available on Wikipedia, he had lost at least GB£10,000 (equivalent to about £11,000 in 2019) in income and his business as a wildlife photographer was being harmed. In December 2014, the United States Copyright Office stated that works created by a non-human, such as a photograph taken by a monkey, are not copyrightable. A number of legal experts in the US and UK have argued that Slater's role in the photographic process may have been sufficient to establish a valid copyright claim, though this decision would have to be made by a court.

In a separate dispute, PETA tried to use the monkey selfies to establish a legal precedent that animals should be declared copyright holders. Slater had published a book containing the photographs through self-publishing company Blurb, Inc. In September 2015, PETA filed a lawsuit against Slater and Blurb, requesting that the monkey be assigned the copyright and that PETA be appointed to administer proceeds from the photos for the endangered species' benefit. In dismissing PETA's case, the court ruled that a monkey cannot own copyright, under US law. PETA appealed, and in September 2017, both PETA and the photographer agreed to a settlement in which Slater would donate a portion of future revenues on the photographs to wildlife organizations. However, the court of appeals declined to dismiss the appeal and declined to vacate the lower court judgment. In April 2018, the appeals court affirmed that animals cannot legally hold copyrights and expressed concern that PETA's motivations had been to promote their own interests rather than to protect the legal rights of animals.

🔗 Espionage 🔗 Internet 🔗 Telecommunications 🔗 Computer Security 🔗 Computer Security/Computing

Van Eck phreaking (also known as Van Eck Radiation) is a form of eavesdropping in which special equipment is used to pick up side-band electromagnetic emissions from electronic devices that correlate to hidden signals or data for the purpose of recreating these signals or data in order to spy on the electronic device. Side-band electromagnetic radiation emissions are present in (and with the proper equipment, can be captured from) keyboards, computer displays, printers, and other electronic devices.

In 1985, Wim van Eck published the first unclassified technical analysis of the security risks of emanations from computer monitors. This paper caused some consternation in the security community, which had previously believed that such monitoring was a highly sophisticated attack available only to governments; van Eck successfully eavesdropped on a real system, at a range of hundreds of metres, using just $15 worth of equipment plus a television set.

As a consequence of this research, such emanations are sometimes called "van Eck radiation", and the eavesdropping technique van Eck phreaking. Government researchers were already aware of the danger, as Bell Labs had noted this vulnerability to secure teleprinter communications during World War II and was able to produce 75% of the plaintext being processed in a secure facility from a distance of 80 feet (24 metres). Additionally the NSA published Tempest Fundamentals, NSA-82-89, NACSIM 5000, National Security Agency (Classified) on February 1, 1982. In addition, the van Eck technique was successfully demonstrated to non-TEMPEST personnel in Korea during the Korean War in the 1950s.

While Phreaking is the process of exploiting telephone networks, it is used here because of its connection to eavesdropping. Van Eck phreaking of CRT displays is the process of eavesdropping on the contents of a CRT by detecting its electromagnetic emissions.