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πŸ”— Time formatting and storage bugs

πŸ”— Computer science πŸ”— Time

In computer science, time formatting and storage bugs are a class of software bugs which may cause time and date calculation or display to be improperly handled. These are most commonly manifestations of arithmetic overflow, but can also be the result of other issues. The most well-known consequence of bugs of this type is the Y2K problem, but many other milestone dates or times exist that have caused or will cause problems depending on various programming deficiencies.

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πŸ”— Superformula

πŸ”— Mathematics

The superformula is a generalization of the superellipse and was proposed by Johan Gielis around 2000. Gielis suggested that the formula can be used to describe many complex shapes and curves that are found in nature. Gielis has filed a patent application related to the synthesis of patterns generated by the superformula.

In polar coordinates, with r {\displaystyle r} the radius and Ο† {\displaystyle \varphi } the angle, the superformula is:

r ( Ο† ) = ( | cos ⁑ ( m 1 Ο† 4 ) a | n 2 + | sin ⁑ ( m 2 Ο† 4 ) b | n 3 ) βˆ’ 1 n 1 . {\displaystyle r\left(\varphi \right)=\left(\left|{\frac {\cos \left({\frac {m_{1}\varphi }{4}}\right)}{a}}\right|^{n_{2}}+\left|{\frac {\sin \left({\frac {m_{2}\varphi }{4}}\right)}{b}}\right|^{n_{3}}\right)^{-{\frac {1}{n_{1}}}}.}

By choosing different values for the parameters a , b , m 1 , m 2 , n 1 , n 2 , {\displaystyle a,b,m_{1},m_{2},n_{1},n_{2},} and n 3 , {\displaystyle n_{3},} different shapes can be generated.

The formula was obtained by generalizing the superellipse, named and popularized by Piet Hein, a Danish mathematician.

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πŸ”— United States Camel Corps

πŸ”— United States πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— United States/American Old West πŸ”— Military history/Military logistics and medicine πŸ”— Military history/American Civil War

The United States Camel Corps was a mid-19th-century experiment by the United States Army in using camels as pack animals in the Southwestern United States. While the camels proved to be hardy and well suited to travel through the region, the Army declined to adopt them for military use. The Civil War interfered with the experiment and it was eventually abandoned; the animals were sold at auction.

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πŸ”— Utah Data Center

πŸ”— United States/U.S. Government πŸ”— United States πŸ”— Mass surveillance πŸ”— Espionage πŸ”— Cryptography πŸ”— Cryptography/Computer science πŸ”— United States/Utah

The Utah Data Center (UDC), also known as the Intelligence Community Comprehensive National Cybersecurity Initiative Data Center, is a data storage facility for the United States Intelligence Community that is designed to store data estimated to be on the order of exabytes or larger. Its purpose is to support the Comprehensive National Cybersecurity Initiative (CNCI), though its precise mission is classified. The National Security Agency (NSA) leads operations at the facility as the executive agent for the Director of National Intelligence. It is located at Camp Williams near Bluffdale, Utah, between Utah Lake and Great Salt Lake and was completed in May 2019 at a cost of $1.5 billion.

The Utah Data Center, code-named Bumblehive, is the first Intelligence Community Comprehensive National Cyber-security Initiative (IC CNCI) data center designed to support the US intelligence community. The "massive data repository" is designed to cope with the large increase in digital data that has accompanied the rise of the global internet.

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πŸ”— Ubuntu Philosophy

πŸ”— Human rights πŸ”— Africa πŸ”— Philosophy πŸ”— Philosophy/Ethics

Ubuntu (Zulu pronunciation:Β [ΓΉΙ“ΓΊntΚΌΓΉ]) is a Nguni Bantu term meaning "humanity." It is often translated as "I am because we are," or "humanity towards others," or in Xhosa, "umntu ngumntu ngabantu" but is often used in a more philosophical sense to mean "the belief in a universal bond of sharing that connects all humanity."

In Southern Africa, it has come to be used as a contested term for a kind of humanist philosophy, ethic, or ideology, also known as Ubuntuism propagated in the Africanisation (transition to majority rule) process of these countries during the 1980s and 1990s.

Since the transition to democracy in South Africa with the Nelson Mandela presidency in 1994, the term has become more widely known outside of Southern Africa, notably popularised to English-language readers through the ubuntu theology of Desmond Tutu. Tutu was the chairman of the South African Truth and Reconciliation Commission (TRC), and many have argued that ubuntu was a formative influence on the TRC.

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πŸ”— Penrose Tiling

πŸ”— Mathematics

A Penrose tiling is an example of an aperiodic tiling. Here, a tiling is a covering of the plane by non-overlapping polygons or other shapes, and aperiodic means that shifting any tiling with these shapes by any finite distance, without rotation, cannot produce the same tiling. However, despite their lack of translational symmetry, Penrose tilings may have both reflection symmetry and fivefold rotational symmetry. Penrose tilings are named after mathematician and physicist Roger Penrose, who investigated them in the 1970s.

There are several different variations of Penrose tilings with different tile shapes. The original form of Penrose tiling used tiles of four different shapes, but this was later reduced to only two shapes: either two different rhombi, or two different quadrilaterals called kites and darts. The Penrose tilings are obtained by constraining the ways in which these shapes are allowed to fit together. This may be done in several different ways, including matching rules, substitution tiling or finite subdivision rules, cut and project schemes, and coverings. Even constrained in this manner, each variation yields infinitely many different Penrose tilings.

Penrose tilings are self-similar: they may be converted to equivalent Penrose tilings with different sizes of tiles, using processes called inflation and deflation. The pattern represented by every finite patch of tiles in a Penrose tiling occurs infinitely many times throughout the tiling. They are quasicrystals: implemented as a physical structure a Penrose tiling will produce diffraction patterns with Bragg peaks and five-fold symmetry, revealing the repeated patterns and fixed orientations of its tiles. The study of these tilings has been important in the understanding of physical materials that also form quasicrystals. Penrose tilings have also been applied in architecture and decoration, as in the floor tiling shown.

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πŸ”— Laika

πŸ”— Soviet Union πŸ”— Russia πŸ”— Russia/technology and engineering in Russia πŸ”— Spaceflight πŸ”— Dogs πŸ”— Russia/science and education in Russia πŸ”— Russia/history of Russia

Laika (Russian: Π›Π°ΠΉΠΊΠ°; c. 1954 – 3 November 1957) was a Soviet space dog who was one of the first animals in space and the first to orbit the Earth. A stray mongrel from the streets of Moscow, she flew aboard the Sputnik 2 spacecraft, launched into low orbit on 3 November 1957. As the technology to de-orbit had not yet been developed, Laika's survival was never expected. She died of overheating hours into the flight, on the craft's fourth orbit.

Little was known about the impact of spaceflight on living creatures at the time of Laika's mission, and animal flights were viewed by engineers as a necessary precursor to human missions. The experiment, which monitored Laika's vital signs, aimed to prove that a living organism could survive being launched into orbit and continue to function under conditions of weakened gravity and increased radiation, providing scientists with some of the first data on the biological effects of spaceflight.

Laika died within hours from overheating, possibly caused by a failure of the central R‑7 sustainer to separate from the payload. The true cause and time of her death were not made public until 2002; instead, it was widely reported that she died when her oxygen ran out on day six or, as the Soviet government initially claimed, she was euthanised prior to oxygen depletion. In 2008, a small monument to Laika depicting her standing atop a rocket was unveiled near the military research facility in Moscow that prepared her flight. She also appears on the Monument to the Conquerors of Space in Moscow.

πŸ”— Tacit Programming

πŸ”— Computer science

Tacit programming, also called point-free style, is a programming paradigm in which function definitions do not identify the arguments (or "points") on which they operate. Instead the definitions merely compose other functions, among which are combinators that manipulate the arguments. Tacit programming is of theoretical interest, because the strict use of composition results in programs that are well adapted for equational reasoning. It is also the natural style of certain programming languages, including APL and its derivatives, and concatenative languages such as Forth. The lack of argument naming gives point-free style a reputation of being unnecessarily obscure, hence the epithet "pointless style".

Unix scripting uses the paradigm with pipes.

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πŸ”— Grace Hopper

πŸ”— United States/U.S. Government πŸ”— United States πŸ”— Biography πŸ”— Computing πŸ”— Military history πŸ”— Military history/North American military history πŸ”— United States/Military history - U.S. military history πŸ”— Military history/Military science, technology, and theory πŸ”— New York City πŸ”— Women scientists πŸ”— Biography/science and academia πŸ”— Women's History πŸ”— Military history/Military biography πŸ”— Biography/military biography πŸ”— Software πŸ”— Software/Computing πŸ”— Military history/Maritime warfare πŸ”— Pritzker Military Library

Grace Brewster Murray Hopper (nΓ©eΒ Murray December 9, 1906 – January 1, 1992) was an American computer scientist and United States Navy rear admiral. One of the first programmers of the Harvard MarkΒ I computer, she was a pioneer of computer programming who invented one of the first linkers. She popularized the idea of machine-independent programming languages, which led to the development of COBOL, an early high-level programming language still in use today.

Prior to joining the Navy, Hopper earned a Ph.D. in mathematics from Yale University and was a professor of mathematics at Vassar College. Hopper attempted to enlist in the Navy during World War II but was rejected because she was 34 years old. She instead joined the Navy Reserves. Hopper began her computing career in 1944 when she worked on the Harvard Mark I team led by Howard H. Aiken. In 1949, she joined the Eckert–Mauchly Computer Corporation and was part of the team that developed the UNIVAC I computer. At Eckert–Mauchly she began developing the compiler. She believed that a programming language based on English was possible. Her compiler converted English terms into machine code understood by computers. By 1952, Hopper had finished her program linker (originally called a compiler), which was written for the A-0 System. During her wartime service, she co-authored three papers based on her work on the Harvard Mark 1.

In 1954, Eckert–Mauchly chose Hopper to lead their department for automatic programming, and she led the release of some of the first compiled languages like FLOW-MATIC. In 1959, she participated in the CODASYL consortium, which consulted Hopper to guide them in creating a machine-independent programming language. This led to the COBOL language, which was inspired by her idea of a language being based on English words. In 1966, she retired from the Naval Reserve, but in 1967 the Navy recalled her to active duty. She retired from the Navy in 1986 and found work as a consultant for the Digital Equipment Corporation, sharing her computing experiences.

The U.S. Navy Arleigh Burke-class guided-missile destroyer USSΒ Hopper was named for her, as was the Cray XE6 "Hopper" supercomputer at NERSC. During her lifetime, Hopper was awarded 40 honorary degrees from universities across the world. A college at Yale University was renamed in her honor. In 1991, she received the National Medal of Technology. On November 22, 2016, she was posthumously awarded the Presidential Medal of Freedom by President Barack Obama.

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πŸ”— GΓΆdel, Escher, Bach

πŸ”— Philosophy πŸ”— Philosophy/Philosophical literature πŸ”— Books πŸ”— Philosophy/Logic

GΓΆdel, Escher, Bach: An Eternal Golden Braid, also known as GEB, is a 1979 book by Douglas Hofstadter. By exploring common themes in the lives and works of logician Kurt GΓΆdel, artist M. C. Escher, and composer Johann Sebastian Bach, the book expounds concepts fundamental to mathematics, symmetry, and intelligence. Through illustration and analysis, the book discusses how, through self-reference and formal rules, systems can acquire meaning despite being made of "meaningless" elements. It also discusses what it means to communicate, how knowledge can be represented and stored, the methods and limitations of symbolic representation, and even the fundamental notion of "meaning" itself.

In response to confusion over the book's theme, Hofstadter emphasized that GΓΆdel, Escher, Bach is not about the relationships of mathematics, art, and musicβ€”but rather about how cognition emerges from hidden neurological mechanisms. One point in the book presents an analogy about how individual neurons in the brain coordinate to create a unified sense of a coherent mind by comparing it to the social organization displayed in a colony of ants.

The tagline "a metaphorical fugue on minds and machines in the spirit of Lewis Carroll" was used by the publisher to describe the book.

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