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🔗 Companies 🔗 History 🔗 Architecture 🔗 Buddhism 🔗 Japan 🔗 Japan/History 🔗 Japan/Business and economy

Kongō Gumi Co., Ltd. (株式会社金剛組, Kabushiki Gaisha Kongō Gumi) is a Japanese construction company which was the world's oldest continuously ongoing independent company, operating for over 1,400 years. In January 2006, it became a subsidiary of Takamatsu.

🔗 Mathematics

Wang tiles (or Wang dominoes), first proposed by mathematician, logician, and philosopher Hao Wang in 1961, are a class of formal systems. They are modelled visually by square tiles with a color on each side. A set of such tiles is selected, and copies of the tiles are arranged side by side with matching colors, without rotating or reflecting them.

The basic question about a set of Wang tiles is whether it can tile the plane or not, i.e., whether an entire infinite plane can be filled this way. The next question is whether this can be done in a periodic pattern.

🔗 Biography 🔗 Systems 🔗 Biography/arts and entertainment

John Gall (September 18, 1925 – December 15, 2014) was an American author and retired pediatrician. Gall is known for his 1975 book General systemantics: an essay on how systems work, and especially how they fail..., a critique of systems theory. One of the statements from this book has become known as Gall's law.

🔗 Biography 🔗 China/Chinese history 🔗 Italy 🔗 China

Katarina Vilioni (died 1342) was one of the first Europeans known to have resided in China. She was apparently a member of a Genoese trading family that lived in Yangzhou during the mid-14th century.

Vilioni is known through her tombstone, which was rediscovered at Yangzhou in 1951. It suggests that Vilioni died in 1342 and was the daughter of a man named Domenico Vilioni.

🔗 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.

🔗 Computing 🔗 Computer science 🔗 Computing/Software 🔗 Computing/Computer science

Comb sort is a relatively simple sorting algorithm originally designed by Włodzimierz Dobosiewicz and Artur Borowy in 1980, later rediscovered by Stephen Lacey and Richard Box in 1991. Comb sort improves on bubble sort.

🔗 Computing 🔗 Computing/Networking

The Network Control Program (NCP) provided the middle layers of the protocol stack running on host computers of the ARPANET, the predecessor to the modern Internet.

NCP preceded the Transmission Control Protocol (TCP) as a transport layer protocol used during the early ARPANET. NCP was a simplex protocol that utilized two port addresses, establishing two connections, for two-way communications. An odd and an even port were reserved for each application layer application or protocol. The standardization of TCP and UDP reduced the need for the use of two simplex ports for each application down to one duplex port.

🔗 Computing 🔗 Computing/Computer hardware

The Saturn family of 4-bit (datapath) microprocessors was developed by Hewlett-Packard in the 1980s first for the HP-71B handheld computer and then later for various HP calculators (starting with the HP-18C). It succeeded the Nut family of processors used in earlier calculators. The original Saturn chip was first used in the HP-71B hand-held BASIC-programmable computer, introduced in 1984. Later models of the family powered the popular HP 48 series of calculators. The HP48SX and HP48S were the last models to use genuine Saturn processors manufactured by HP. Later calculator models used Saturn processors manufactured by NEC. The HP 49 series initially used the Saturn CPU as well, until the NEC fab could no longer manufacture the processor for technical reasons in 2003. Therefore, starting with the HP 49g+ model in 2003, the calculators switched to a Samsung S3C2410 processor with an ARM920T core (part of the ARMv4T architecture) which ran an emulator of the Saturn hardware in software. In 2000, the HP 39G and HP 40G were the last calculators introduced based on the actual NEC fabricated Saturn hardware. The last calculators based on the Saturn emulator were the HP 39gs, HP 40gs and HP 50g in 2006, as well as the 2007 revision of the hp 48gII. The HP 50g, the last calculator utilizing this emulator, was discontinued in 2015 when Samsung stopped producing the ARM processor on which it was based.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history

Operation Dark Winter was the code name for a senior-level bio-terrorist attack simulation conducted from June 22–23, 2001. It was designed to carry out a mock version of a covert and widespread smallpox attack on the United States. Tara O'Toole and Thomas Inglesby of the Johns Hopkins Center for Civilian Biodefense Strategies (CCBS) / Center for Strategic and International Studies (CSIS), and Randy Larsen and Mark DeMier of Analytic Services were the principal designers, authors, and controllers of the Dark Winter project.

Dark Winter was focused on evaluating the inadequacies of a national emergency response during the use of a biological weapon against the American populace. The exercise was solely intended to establish preventive measures and response strategies by increasing governmental and public awareness of the magnitude and potential of such a threat posed by biological weapons.

Dark Winter's simulated scenario involved an initial localized smallpox attack on Oklahoma City, Oklahoma with additional smallpox attack cases in Georgia and Pennsylvania. The simulation was then designed to spiral out of control. This would create a contingency in which the National Security Council struggles to determine both the origin of the attack as well as deal with containing the spreading virus. By not being able to keep pace with the disease's rate of spread, a new catastrophic contingency emerges in which massive civilian casualties would overwhelm America's emergency response capabilities.

The disastrous contingencies that would result in the massive loss of civilian life were used to exploit the weaknesses of the U.S. health care infrastructure and its inability to handle such a threat. The contingencies were also meant to address the widespread panic that would emerge and which would result in mass social breakdown and mob violence. Exploits would also include the many difficulties that the media would face when providing American citizens with the necessary information regarding safety procedures.

🔗 Time

Segal's law is an adage that states:

A man with a watch knows what time it is. A man with two watches is never sure.

At surface level, the adage emphasizes the consistency that arises when information comes from a single source and points out the potential pitfalls of having too much conflicting information. However, the underlying message is to question the apparent certainty of anyone who only has one source of information. The man with one watch has no way to identify error or uncertainty.