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🔗 Computing 🔗 Computing/Computer hardware

Rekursiv was a computer processor designed by David M. Harland in the mid-1980s for Linn Smart Computing in Glasgow, Scotland. It was one of the few computer architectures intended to implement object-oriented concepts directly in hardware, a form of high-level language computer architecture. The Rekursiv operated directly on objects rather than bits, nibbles, bytes and words. Virtual memory was used as a persistent object store and unusually, the processor instruction set supported recursion (hence the name).

The project originated in an initiative within the hi-fi manufacturer Linn Products to improve its manufacturing automation systems, which at the time ran on a DEC VAX minicomputer. This resulted in the design of Lingo, an object-oriented programming language derived from Smalltalk and ALGOL. Due to the poor performance of Lingo on the VAX, a subsidiary company, Linn Smart Computing Ltd., was formed to develop a new processor to efficiently run Lingo.

The Rekursiv processor consisted of four gate-array chips named Numerik (32-bit ALU), Logik (instruction sequencer), Objekt (object-oriented memory management unit) and Klock (processor clock and support logic). A small number of prototype VMEbus boards, called Hades, comprising these four chips plus 80 MB of RAM were produced. These were intended for installation in a host system such as a Sun-3 workstation.

Although the Rekursiv was never fully developed and was not a commercial success, several Hades boards were used in academic research projects in the UK. The last known copy of a Rekursiv computer ended up at the bottom of the Forth and Clyde canal in Glasgow.

🔗 Germany

F60 is the series designation of five overburden conveyor bridges used in brown coal (lignite) opencast mining in the Lusatian coalfields in Germany. They were built by the former Volkseigener Betrieb TAKRAF in Lauchhammer and are the largest movable technical industrial machines in the world. As overburden conveyor bridges, they transport the overburden which lies over the coal seam. The cutting height is 60 m (200 ft), hence the name F60. In total, the F60 is up to 80 m (260 ft) high and 240 m (790 ft) wide; with a length of 502 m (1,647 ft), it is described as the lying Eiffel tower, making these behemoths not only the longest vehicle ever made—beating Seawise Giant, the longest ship—but the largest vehicle by physical dimensions ever made by humankind. In operating condition, it weighs 13,600 metric tons making the F60 also one of the heaviest land vehicles ever made, beaten only by Bagger 293, which is a giant bucket-wheel excavator. Nevertheless, despite its immense size, it is operated by only a crew of 14.

The first conveyor bridge was built from 1969 to 1972, being equipped with a feeder bridge in 1977. The second was built from 1972 to 1974, having been equipped with a feeder bridge during construction. The third conveyor bridge was built from 1976 to 1978, being provided with a feeder bridge in 1985. The fourth and fifth conveyor bridges were built 1986–1988 and 1988–1991 respectively.

There are still four F60s in operation in the Lusatian coalfields today: in the brown coal opencast mines in Jänschwalde (Brandenburg, near Jänschwalde Power Station), Welzow-Süd (Brandenburg, near Schwarze Pumpe Power Station), Nochten and Reichwalde (Saxony, both near Boxberg Power Station). The fifth F60, the last one built, is in Lichterfeld-Schacksdorf and is accessible to visitors.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry

The Apollo Affair was a 1965 incident in which a US company, Nuclear Materials and Equipment Corporation (NUMEC), in the Pittsburgh suburbs of Apollo and Parks Township, Pennsylvania was investigated for losing 200–600 pounds (91–272 kg) of highly enriched uranium, with suspicions that it had gone to Israel's nuclear weapons program.

From 1965 to 1980, the Federal Bureau of Investigation (FBI) investigated Zalman Shapiro, the company's president, over the loss of 206 pounds (93 kg) of highly enriched uranium. The Atomic Energy Commission, the Central Intelligence Agency (CIA), other government agencies, and inquiring reporters conducted similar investigations, and no charges were ever filed. A General Accounting Office study of the investigations declassified in May 2010 stated "We believe a timely, concerted effort on the part of these three agencies would have greatly aided and possibly solved the NUMEC diversion questions, if they desired to do so."

In February 1976 the CIA briefed senior staff at the Nuclear Regulatory Commission (NRC) about the matter, stating that the CIA believed the missing highly enriched uranium went to Israel. The NRC informed the White House, leading to President-elect Carter being briefed about the investigation. Carter asked for an assessment by his National Security Advisor, whose staff concluded "The CIA case is persuasive, though not conclusive."

Some remain convinced that Israel received 206 pounds (93 kg) or more of highly enriched uranium from NUMEC, particularly given the visit of Rafi Eitan, later revealed as an Israeli spy and who was later involved in the Jonathan Pollard incident. In June 1986, analyst Anthony Cordesman told United Press International:

There is no conceivable reason for Eitan to have gone [to the Apollo plant] but for the nuclear material.”

In his 1991 book, The Samson Option, Seymour Hersh concluded that Shapiro did not divert any uranium; rather "it ended up in the air and water of the city of Apollo as well as in the ducts, tubes, and floors of the NUMEC plant." He also wrote that Shapiro's meetings with senior Israeli officials in his home were related to protecting the water supply in Israel rather than any diversion of nuclear material or information.

A later investigation was conducted by the Nuclear Regulatory Commission (successor to the AEC) regarding an additional 198 pounds (90 kg) of uranium that was found to be missing between 1974 and 1976, after the plant had been purchased by Babcock & Wilcox and Shapiro was no longer associated with the company. That investigation found that more than 110 pounds (50 kg) of it could be accounted for by what was called "previously unidentified and undocumented loss mechanisms", including "contamination of workers' clothes, losses from scrubber systems, material embedded in the flooring, and residual deposits in the processing equipment." Hersh further quoted one of the main investigators, Carl Duckett, as saying "I know of nothing at all to indicate that Shapiro was guilty."

In 1993, Glenn T. Seaborg, former head of the Atomic Energy Commission wrote a book, The Atomic Energy Commission under Nixon, Adjusting to Troubled Times which devoted a chapter to Shapiro and NUMEC, the last sentence of which states:

Distinguished as Shapiro's career has been, one cannot but wonder whether it might not have been even more illustrious had these unjust charges not been leveled against him.

Later U.S. Department of Energy records show that NUMEC had the largest highly enriched uranium inventory loss of all U.S. commercial sites, with a 269 kilograms (593 lb) inventory loss before 1968, and 76 kilograms (168 lb) thereafter.

At the prompting of Zalman Shapiro's lawyer, senator Arlen Specter asked the Nuclear Regulatory Commission (NRC) to clear him of any suspicion of diversion in August 2009. The NRC refused, stating:

NRC found no documents that provided specific evidence that the diversion of nuclear materials occurred. However, consistent with previous Commission statements, NRC does not have information that would allow it to unequivocally conclude that nuclear material was not diverted from the site, nor that all previously unaccounted for material was accounted for during the decommissioning of the site.

In 2014, further documents about the investigation were declassified, though still heavily redacted.

The U.S. Army Corps of Engineers is overseeing a cleanup of contaminated land at the site of NUMEC's waste disposal. The project was scheduled to be completed in 2015, but the discovery of a substantially larger amount of contamination resulted in a seven year delay. Excavation is now scheduled to begin in 2021, with an estimated project time of 10 years.

🔗 Transhumanism 🔗 Alternative Views 🔗 Futures studies

American author, inventor and futurist Raymond Kurzweil has become well known for his predictions about artificial intelligence and the human species, mainly concerning the technological singularity. He predicts that Artificial Intelligence would outsmart the human brain in computational capabilities by mid-21st century. His first book, The Age of Intelligent Machines, published in 1990, put forth his theories on the results of the increasing use of technology and predicted the explosive growth in the internet, among other predictions. Later works, 1999's The Age of Spiritual Machines and 2005's The Singularity is Near outlined other theories including the rise of clouds of nano-robots (nanobots) called foglets and the development of Human Body 2.0 and 3.0, whereby nanotechnology is incorporated into many internal organs.

🔗 Computing 🔗 Mathematics

Codd's cellular automaton is a cellular automaton (CA) devised by the British computer scientist Edgar F. Codd in 1968. It was designed to recreate the computation- and construction-universality of von Neumann's CA but with fewer states: 8 instead of 29. Codd showed that it was possible to make a self-reproducing machine in his CA, in a similar way to von Neumann's universal constructor, but never gave a complete implementation.

🔗 Internet 🔗 Computing 🔗 Antarctica

.aq is the Internet country code top-level domain (ccTLD) for Antarctica (itself not a country). It is derived from the French Antarctique and is reserved for organizations that work in Antarctica or promote the Antarctic and Southern Ocean regions. It is administered by Peter Mott of Antarctica Network Information Centre Limited from Christchurch, New Zealand.

.aq domain names are available free of charge, and registration is granted for a period of 24 months. As a general rule, registrants are only allocated a single .aq domain name. The registry does not have a website. Registration is only possible by contacting Antarctica Network Information Centre Limited.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Aviation/aircraft 🔗 Aviation/aircraft engine

The Aircraft Nuclear Propulsion (ANP) program and the preceding Nuclear Energy for the Propulsion of Aircraft (NEPA) project worked to develop a nuclear propulsion system for aircraft. The United States Army Air Forces initiated Project NEPA on May 28, 1946. NEPA operated until May 1951, when the project was transferred to the joint Atomic Energy Commission (AEC)/USAF ANP. The USAF pursued two different systems for nuclear-powered jet engines, the Direct Air Cycle concept, which was developed by General Electric, and Indirect Air Cycle, which was assigned to Pratt & Whitney. The program was intended to develop and test the Convair X-6, but was cancelled in 1961 before that aircraft was built. The total cost of the program from 1946 to 1961 was about $1 billion.

🔗 Video games 🔗 Computing

The ZX81 is a home computer that was produced by Sinclair Research and manufactured in Dundee, Scotland, by Timex Corporation. It was launched in the United Kingdom in March 1981 as the successor to Sinclair's ZX80 and designed to be a low-cost introduction to home computing for the general public. It was hugely successful; more than 1.5 million units were sold. In the United States it was initially sold as the ZX-81 under license by Timex. Timex later produced its own versions of the ZX81: the Timex Sinclair 1000 and Timex Sinclair 1500. Unauthorized ZX81 clones were produced in several countries.

The ZX81 was designed to be small, simple, and above all, inexpensive, with as few components as possible. Video output is to a television set rather than a dedicated monitor. Programs and data are loaded and saved onto compact audio cassettes. It uses only four silicon chips and a mere 1 KB of memory. There is no power switch or any moving parts with the exception of a VHF TV channel selector switch present in some models. It has a pressure-sensitive membrane keyboard. The ZX81's limitations prompted a market in third-party peripherals to improve its capabilities. Its distinctive case and keyboard brought designer Rick Dickinson a Design Council award.

The ZX81 could be bought by mail order preassembled or, for a lower price, in kit form. It was the first inexpensive mass-market home computer to be sold by high street stores, led by W. H. Smith and soon many other retailers. The ZX81 marked the point when computing in Britain became an activity for the general public rather than the preserve of businessmen and electronics hobbyists. It produced a huge community of enthusiasts, some of whom founded their own businesses producing software and hardware for the ZX81. Many went on to play major roles in the British computer industry. The ZX81's commercial success made Sinclair Research one of Britain's leading computer manufacturers and earned a fortune and an eventual knighthood for the company's founder Sir Clive Sinclair.

🔗 China/Chinese history 🔗 China 🔗 Central Asia 🔗 Archaeology 🔗 Buddhism 🔗 Former countries

Loulan, also called Krorän or Kroraina (simplified Chinese: 楼兰; traditional Chinese: 樓蘭; pinyin: Lóulán; Uyghur: كروران, Кроран‎, ULY: Kroran) was an ancient kingdom based around an important oasis city along the Silk Road already known in the 2nd century BCE on the northeastern edge of the Lop Desert. The term Loulan is the Chinese transcription of the native name Krorän and is used to refer to the city near Lop Nur as well as the kingdom.

The kingdom was renamed Shanshan (鄯善) after its king was assassinated by an envoy of the Han dynasty in 77 BCE; however, the town at the northwestern corner of the brackish desert lake Lop Nur retained the name of Loulan. The kingdom included at various times settlements such as Niya, Charklik, Miran, and Qiemo. It was intermittently under Chinese control from the early Han dynasty onward until its abandonment centuries later. The ruins of Loulan are near the now-desiccated Lop Nur in the Bayingolin Mongol Autonomous Prefecture, Xinjiang, and they are now completely surrounded by desert.

🔗 Computing 🔗 Computing/Software 🔗 Computing/Computer science

Flashsort is a distribution sorting algorithm showing linear computational complexity ${\displaystyle O(n)}$ for uniformly distributed data sets and relatively little additional memory requirement. The original work was published in 1998 by Karl-Dietrich Neubert.