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🔗 Robotics 🔗 Electronics

Surface-mount technology (SMT) component placement systems, commonly called pick-and-place machines or P&Ps, are robotic machines which are used to place surface-mount devices (SMDs) onto a printed circuit board (PCB). They are used for high speed, high precision placing of a broad range of electronic components, like capacitors, resistors, integrated circuits onto the PCBs which are in turn used in computers, consumer electronics as well as industrial, medical, automotive, military and telecommunications equipment. Similar equipment exists for through-hole components. This type of equipment is sometimes also used to package microchips using the flip chip method.

🔗 Computing 🔗 Computing/Networking

In computer networking, IP over Avian Carriers (IPoAC) is a proposal to carry Internet Protocol (IP) traffic by birds such as homing pigeons. IP over Avian Carriers was initially described in RFC 1149, a Request for Comments (RFC) issued by the Internet Engineering Task Force (IETF), written by D. Waitzman, and released on April 1, 1990. It is one of several April Fools' Day Request for Comments.

Waitzman described an improvement of his protocol in RFC 2549, IP over Avian Carriers with Quality of Service (1 April 1999). Later, in RFC 6214—released on 1 April 2011, and 13 years after the introduction of IPv6—Brian Carpenter and Robert Hinden published Adaptation of RFC 1149 for IPv6.

IPoAC has been successfully implemented, but for only nine packets of data, with a packet loss ratio of 55% (due to operator error), and a response time ranging from 3,000 seconds (≈54 minutes) to over 6,000 seconds (≈1.77 hours). Thus, this technology suffers from poor latency. Nevertheless, for large transfers, avian carriers are capable of high average throughput when carrying flash memory devices, effectively implementing a sneakernet. During the last 20 years, the information density of storage media and thus the bandwidth of an avian carrier has increased 3 times as fast as the bandwidth of the Internet. IPoAC may achieve bandwidth peaks of orders of magnitude more than the Internet when used with multiple avian carriers in rural areas. For example: If 16 homing pigeons are given eight 512 GB SD cards each, and take an hour to reach their destination, the throughput of the transfer would be 145.6 Gbit/s, excluding transfer to and from the SD cards.

🔗 Biography 🔗 Mathematics 🔗 Germany 🔗 Physics 🔗 Women scientists 🔗 Biography/science and academia 🔗 Women's History 🔗 Women writers 🔗 Physics/Biographies 🔗 Toys

🔗 Computing

The R3000 is a 32-bit RISC microprocessor chipset developed by MIPS Computer Systems that implemented the MIPS I instruction set architecture (ISA). Introduced in June 1988, it was the second MIPS implementation, succeeding the R2000 as the flagship MIPS microprocessor. It operated at 20, 25 and 33.33 MHz.

The MIPS 1 instruction set is small compared to those of the contemporary 80x86 and 680x0 architectures, encoding only more commonly used operations and supporting few addressing modes. Combined with its fixed instruction length and only three different types of instruction formats, this simplified instruction decoding and processing. It employed a 5-stage instruction pipeline, enabling execution at a rate approaching one instruction per cycle, unusual for its time.

This MIPS generation supports up to four co-processors. In addition to the CPU core, the R3000 microprocessor includes a Control Processor (CP), which contains a Translation Lookaside Buffer and a Memory Management Unit. The CP works as a coprocessor. Besides the CP, the R3000 can also support an external R3010 numeric coprocessor and two other external coprocessors.

The R3000 CPU does not include level 1 cache. Instead, its on-chip cache controller operates external data and instruction caches of up to 256 KB each. It can access both caches during the same clock cycle.

The R3000 found much success and was used by many companies in their workstations and servers. Users included:

• Ardent Computer
• Digital Equipment Corporation (DEC) for their DECstation workstations and multiprocessor DECsystem servers
• Evans & Sutherland for their Vision (ESV) series workstations
• MIPS Computer Systems for their MIPS RISC/os Unix workstations and servers.
• NEC for their RISC EWS4800 workstations and UP4800 servers.
• Prime Computer
• Pyramid Technology
• Seiko Epson
• Silicon Graphics for their Professional IRIS, Personal IRIS and Indigo workstations, and the multiprocessor Power Series visualization systems
• Sony for their PlayStation and PlayStation 2 (SCPH-10000 to SCPH-700XX - clocked at 37.5 MHz for use as an I/O CPU and at 33.8 MHz for compatibility with PlayStation games) video game consoles, and NEWS workstations, as well as the Bemani System 573 Analog arcade unit, which runs on the R3000A.
• Tandem Computers for their NonStop Cyclone/R and CLX/R fault-tolerant servers
• Whitechapel Workstations for their Hitech-20 workstation
• New Horizons Probe

The R3000 was also used as an embedded microprocessor. When advances in technology rendered it obsolete for high-performance systems, it found continued use in lower-cost designs. Companies such as LSI Logic developed derivatives of the R3000 specifically for embedded systems.

The R3000 was a further development of the R2000 with minor improvements including larger TLB and a faster bus to the external caches. The R3000 die contained 115,000 transistors and measured about 75,000 square mils (48 mm²). MIPS was a fabless semiconductor company, so the R3000 was fabricated by MIPS partners including Integrated Device Technology (IDT), LSI Logic, NEC Corporation, Performance Semiconductor, and others. It was fabricated in a 1.2 μm complementary metal–oxide–semiconductor (CMOS) process with two levels of aluminium interconnect.

Derivatives of the R3000 for non-embedded applications include:

• R3000A - A further development by MIPS introduced in 1989. It operated at clock frequencies up to 40 MHz.
• PR3400 - Developed by Performance Semiconductor, introduced in May 1991, also at up to 40 MHz. It integrated the Performance Semiconductor PR3000A and PR3010A onto a single die.

Derivatives of the R3000 for embedded applications include:

• PR31700 - A 75 MHz microcontroller from Philips Semiconductors. Fabricated in a 0.35 μm process, delivered in a 208-pin LQFP, it operated at 3.3 V and dissipated only 0.35 W.
• RISController - A family of low-end microcontrollers from IDT. Models include the R3041, R3051, R3052, and R3081.
• TX3900 - A microcontroller from Toshiba.
• Mongoose-V - A radiation-hardened and expanded 10–15 MHz CPU for use on spacecraft, it is still in use today in applications such as NASA's New Horizons space probe.

🔗 Linguistics 🔗 Linguistics/Etymology

This is a list of etymologies proposed for the word OK or okay. The majority can be easily classified as false etymologies, or possibly folk etymologies. H. L. Mencken, in The American Language, lists serious candidates and "a few of the more picturesque or preposterous". Allen Walker Read surveyed a variety of explanations in a 1964 article titled The Folklore of "O. K." Eric Partridge described O.K. as "an evergreen of the correspondence column."

🔗 Internet

Do Not Track (DNT) was a proposed HTTP header field, designed to allow internet users to opt-out of tracking by websites—which includes the collection of data regarding a user's activity across multiple distinct contexts, and the retention, use, or sharing of data derived from that activity outside the context in which it occurred.

The Do Not Track header was originally proposed in 2009 by researchers Christopher Soghoian, Sid Stamm, and Dan Kaminsky. Efforts to standardize Do Not Track by the W3C in the Tracking Preference Expression (DNT) Working Group did not make it past the Candidate Recommendation stage and ended in September 2018 due to insufficient deployment and support.Mozilla Firefox became the first browser to implement the feature, while Internet Explorer, Apple's Safari, Opera and Google Chrome all later added support.

DNT is not widely adopted by the industry, with companies citing the lack of legal mandates for its use, as well as unclear standards and guidelines for how websites are to interpret the header. Thus, it is not guaranteed that enabling DNT will actually have any effect at all. The W3C disbanded its DNT working group in January 2019, citing insufficient support and adoption. Apple discontinued support for DNT the following month.

🔗 Games

Nim is a mathematical game of strategy in which two players take turns removing (or "nimming") objects from distinct heaps or piles. On each turn, a player must remove at least one object, and may remove any number of objects provided they all come from the same heap or pile. Depending on the version being played, the goal of the game is either to avoid taking the last object, or to take the last object.

Variants of Nim have been played since ancient times. The game is said to have originated in China—it closely resembles the Chinese game of 捡石子 jiǎn-shízi, or "picking stones"—but the origin is uncertain; the earliest European references to Nim are from the beginning of the 16th century. Its current name was coined by Charles L. Bouton of Harvard University, who also developed the complete theory of the game in 1901, but the origins of the name were never fully explained.

Nim is typically played as a misère game, in which the player to take the last object loses. Nim can also be played as a normal play game, where the player taking the last object wins. This is called normal play because the last move is a winning move in most games, even though it is not the normal way that Nim is played. In either normal play or a misère game, when the number of heaps with at least two objects is exactly equal to one, the next player who takes next can easily win. If this removes either all or all but one objects from the heap that has two or more, then no heaps will have more than one object, so the players are forced to alternate removing exactly one object until the game ends. If the player leaves an even number of non-zero heaps (as the player would do in normal play), the player takes last; if the player leaves an odd number of heaps (as the player would do in misère play), then the other player takes last.

Normal play Nim (or more precisely the system of nimbers) is fundamental to the Sprague–Grundy theorem, which essentially says that in normal play every impartial game is equivalent to a Nim heap that yields the same outcome when played in parallel with other normal play impartial games (see disjunctive sum).

While all normal play impartial games can be assigned a Nim value, that is not the case under the misère convention. Only tame games can be played using the same strategy as misère Nim.

Nim is a special case of a poset game where the poset consists of disjoint chains (the heaps).

The evolution graph of the game of Nim with three heaps is the same as three branches of the evolution graph of the Ulam-Warburton automaton.

At the 1940 New York World's Fair Westinghouse displayed a machine, the Nimatron, that played Nim. From May 11, 1940 to October 27, 1940 only a few people were able to beat the machine in that six week period; if they did they were presented with a coin that said Nim Champ. It was also one of the first ever electronic computerized games. Ferranti built a Nim playing computer which was displayed at the Festival of Britain in 1951. In 1952 Herbert Koppel, Eugene Grant and Howard Bailer, engineers from the W. L. Maxon Corporation, developed a machine weighing 23 kilograms (50 lb) which played Nim against a human opponent and regularly won. A Nim Playing Machine has been described made from TinkerToy.

The game of Nim was the subject of Martin Gardner's February 1958 Mathematical Games column in Scientific American. A version of Nim is played—and has symbolic importance—in the French New Wave film Last Year at Marienbad (1961).

🔗 Biography 🔗 Comedy 🔗 Biography/arts and entertainment 🔗 Japan 🔗 Japan/Biography 🔗 Japan/Owarai 🔗 Japan/Gaijin tarento

Jason David Danielson (born April 9, 1986), known professionally as Atsugiri Jason (厚切りジェイソン, Atsugiri Jeison, lit. "Thick-sliced Jason"), is an American comedian based in Japan and associated with Watanabe Entertainment. Danielson's comedic narrative is based on his confusion with kanji, ending with the punchline, "Why Japanese people?!"

🔗 United States 🔗 Human rights 🔗 History 🔗 Politics 🔗 Politics/American politics 🔗 African diaspora 🔗 United States History 🔗 United States/FBI 🔗 Civil Rights Movement 🔗 United States/U.S. history

COINTELPRO (syllabic abbreviation derived from COunter INTELligence PROgram) (1956–1971) was a series of covert and, at times, illegal projects conducted by the United States Federal Bureau of Investigation (FBI) aimed at surveilling, infiltrating, discrediting, and disrupting American political organizations. FBI records show that COINTELPRO resources targeted groups and individuals that the FBI deemed subversive, including feminist organizations, the Communist Party USA, anti–Vietnam War organizers, activists of the civil rights movement or Black Power movement (e.g. Martin Luther King Jr., the Nation of Islam, and the Black Panther Party), environmentalist and animal rights organizations, the American Indian Movement (AIM), independence movements (such as Puerto Rican independence groups like the Young Lords), and a variety of organizations that were part of the broader New Left. The program also targeted the Ku Klux Klan in 1964.

In another instance in San Diego, the FBI financed, armed, and controlled an extreme right-wing group of former members of the Minutemen anti-communist para-military organization, transforming it into a group called the Secret Army Organization that targeted groups, activists, and leaders involved in the Anti-War Movement, using both intimidation and violent acts.

The FBI has used covert operations against domestic political groups since its inception; however, covert operations under the official COINTELPRO label took place between 1956 and 1971. COINTELPRO tactics are still used to this day and have been alleged to include discrediting targets through psychological warfare; smearing individuals and groups using forged documents and by planting false reports in the media; harassment; wrongful imprisonment; and illegal violence, including assassination. The FBI's stated motivation was "protecting national security, preventing violence, and maintaining the existing social and political order".

Beginning in 1969, leaders of the Black Panther Party were targeted by the COINTELPRO and "neutralized" by being assassinated, imprisoned, publicly humiliated or falsely charged with crimes. Some of the Black Panthers affected included Fred Hampton, Mark Clark, Zayd Shakur, Geronimo Pratt, Mumia Abu-Jamal, and Marshall Conway. Common tactics used by COINTELPRO were perjury, witness harassment, witness intimidation, and withholding of evidence.

FBI Director J. Edgar Hoover issued directives governing COINTELPRO, ordering FBI agents to "expose, disrupt, misdirect, discredit, or otherwise neutralize" the activities of these movements and especially their leaders. Under Hoover, the agent in charge of COINTELPRO was William C. Sullivan. Attorney General Robert F. Kennedy personally authorized some of the programs. Although Kennedy only gave written approval for limited wiretapping of Martin Luther King's phones "on a trial basis, for a month or so", Hoover extended the clearance so his men were "unshackled" to look for evidence in any areas of King's life they deemed worthy.

Arthropod enthusiast, mainly focus on Panarthropod head problem, phylogeny across arthropod subphyla and stem lineage, basal chelicerates, dinocaridids and lobopodians. Sometime drawing stuff, not so well in english, mainly active at Japanese Wikipedia.

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