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Special cities of North Korea

Special cities are one of the first-level administrative divisions within North Korea. There are two top-level cities in North Korea: Rason. Special cities are the higher-ranked administrative divisions in North Korea. There are three kinds of special cities in North Korea; the first level cities have equal status to the provinces. Notes Pyongyang is classified as a capital city, not a special city as Seoul in South Korea. In fact, the North Korean national newspaper and broadcasting say "Pyongyang Chikhalsi"; some sources, most of them coming from South Korea, refer the city as a special city. Moreover, South Korea has corrected the city as a directly governed city, according to a South Korean newspaper in 1994. Note that the official name of Pyongyang would be "Pyongyang-si" in the Republic of Korea, which claims to represent the entire peninsula. Special-level city is the second level administrative division. Kaesong is still a part of North Hwanghae Province. Namp'o is part of South Pyongan province.

Administrative divisions of North Korea List of cities in North Korea Special cities of South Korea The sources for this section are Chosun Ilbo's pages 행정구역 현황 and 행정구역 개편 일지. Dormels, Rainer. North Korea's Cities: Industrial facilities, internal structures and typification. Jimoondang, 2014. ISBN 978-89-6297-167-5

1979 FIFA World Youth Championship

The 1979 FIFA World Youth Championship, the second staging of the FIFA World Youth Championship, was held in Japan from 26 August to 7 September 1979. It was the first FIFA tournament played in Asia; the tournament took place in four cities — Kobe, Omiya and Yokohama — where a total of 32 matches were played, four more than in the previous edition due to the addition of a quarterfinal round in the knockout stage. Argentina won the trophy after beating holders Soviet Union 3–1, in a final held at Tokyo's National Stadium. For a list of all squads that played in the final tournament, see 1979 FIFA World Youth Championship squads. Ramón Díaz of Argentina won the Golden Shoe award for scoring eight goals. In total, 83 goals were scored with none of them credited as own goal. 8 goals Ramón Díaz6 goals Diego Maradona5 goals Andrzej Pałasz4 goals Julio César Romero Igor Ponomaryov Rubén Paz3 goals Gabriel Calderón2 goals 1 goal FIFA World Youth Championship Japan 1979, RSSSF > FIFA World Youth Championship > 1979 FIFA Technical Report All Matches of the Brazilian Soccer Team Todos os Jogos da Seleção Brasileira de Futebol

Deliberate crash landings on extraterrestrial bodies

These are tables of space probes which have been deliberately destroyed at their objects of study by hard landings or crash landings at the end of their respective missions and/or functionality. This suicidal endeavor not only precludes the hazards of orbital space debris and planetary contamination, but provides the opportunity in some cases for terminal science given that the transient light released by the kinetic energy may be available for spectroscopy. After soft landings had been mastered, NASA used crash landings to test whether Moon craters contained ice by crashing space probes into craters and testing the debris that got thrown out. Several rocket stages utilized during the Apollo space program were deliberately crashed on the Moon to aid seismic research, four of the ascent stages of Apollo Lunar Modules were deliberately crashed onto the Moon after they had fulfilled their function; the Deep Impact mission had its own purpose-built impactor which hit Comet 9P/Tempel 1. Terminal approaches to gas giants which resulted in the destruction of the space probe count as crash landings for the purposes of this article.

The crash landing sites themselves are of interest to space archeology. Luna 1, not itself a lunar orbiter, was the first spacecraft designed as an impactor, it failed to hit the Moon in 1959, thus inadvertently becoming the first man-made object to leave geocentric orbit and enter a heliocentric orbit, where it remains to this day. VenusPioneer Venus Orbiter Pioneer Venus Multiprobe Magellan Venus Express433 ErosNEAR Shoemaker67P/Churyumov–GerasimenkoRosetta List of extraterrestrial orbiters List of landings on extraterrestrial bodies Flyby Space rendezvous

Rayleigh's equation (fluid dynamics)

In fluid dynamics, Rayleigh's equation or Rayleigh stability equation is a linear ordinary differential equation to study the hydrodynamic stability of a parallel and inviscid shear flow. The equation is: − U ″ φ = 0, with U the flow velocity of the steady base flow whose stability is to be studied and z is the cross-stream direction. Further φ is the complex valued amplitude of the infinitesimal streamfunction perturbations applied to the base flow, k is the wavenumber of the perturbations and c is the phase speed with which the perturbations propagate in the flow direction; the prime denotes differentiation with respect to z. The equation is named after Lord Rayleigh, who introduced it in 1880; the Orr–Sommerfeld equation – introduced for the study of stability of parallel viscous flow – reduces to Rayleigh's equation when the viscosity is zero. Rayleigh's equation, together with appropriate boundary conditions, most poses an eigenvalue problem. For given wavenumber k and mean flow velocity U, the eigenvalues are the phase speeds c, the eigenfunctions are the associated streamfunction amplitudes φ.

In general, the eigenvalues form a continuous spectrum. In certain cases additional there may be a discrete spectrum of pairs on complex conjugate values of c. Since the wavenumber k occurs only as a square k 2 in Rayleigh's equation, a solution for wavenumber + k is a solution for the wavenumber − k. Rayleigh's equation only concerns two-dimensional perturbations to the flow. From Squire's theorem it follows that the two-dimensional perturbations are less stable than three-dimensional perturbations. If a real-valued phase speed c is in between the minimum and maximum of U, the problem has so-called critical layers near z = z c r i t where U = c. At the critical layers Rayleigh's equation becomes singular; these were first being studied by Lord Kelvin in 1880. His solution gives rise to a so-called cat's eye pattern of streamlines near the critical layer, when observed in a frame of reference moving with the phase speed c. Consider a parallel shear flow U in the x direction, which varies only in the cross-flow direction z.

The stability of the flow is studied by adding small perturbations to the flow velocity u and w in the x and z directions, respectively. The flow is described using the incompressible Euler equations, which become after linearization – using velocity components U + u and w: ∂ t u + U ∂ x u + w U ′ = − 1 ρ ∂ x p, ∂ t w + U ∂ x w = − 1 ρ ∂ z p and ∂ x u + ∂ z w = 0, wit

Marianna Commercial Historic District

The Marianna Commercial Historic District encompasses the historic civic and commercial heart of Marianna, the county seat of Lee County. The district is focused on two blocks of Main Street and two blocks of Poplar Street, which cross at the northwest corner of Court Square, a city park in which the Gen. Robert E. Lee Monument is found, extends south to include a few buildings on Liberty Street; the city was founded in 1870, its economy developed around cotton and lumber, which were delivered to market by the L'Anguille River, a tributary of the Mississippi River. The downtown developed a short distance west of the city's boat landing, its first brick buildings were built in the 1870s, although the oldest to survive now date to the 1880s, including the elaborate Italianate Hayes & Drake building at 38 South Poplar. Court Square Park has long been a major community meeting point, is faced by the Lee County Courthouse; the district includes seventy buildings, of which forty eight are significant.

The district was listed on the National Register of Historic Places in 2001. National Register of Historic Places listings in Lee County, Arkansas

Nikolai Semashko (medicine)

Nikolai Aleksandrovich Semashko, was a Russian statesman who became People's Commissar of Public Health in 1918, served in that role until 1930. He was one of the organizers of the health system in the Soviet Union, an academician of the Academy of Medical Sciences and of the RSFSR. Nikolai Semashko was born to a teacher in the village of Livenskoe in Yelets uyezd of Oryol guberniya, his mother was a sister of Georgi Plekhanov. In 1891, after graduating from the Yelets gymnasium, Semashko entered the medical faculty of Moscow University. In 1893 he became a member of a Marxist group. In 1895, for his participation in the revolutionary movement, he was arrested and exiled to his home in Livenskoe, under strict police surveillance. In 1901 he graduated from the medical faculty of Kazan University, after which he worked as a doctor in Oryol and in Samara. In 1904 he was an active member of the Nizhny Novgorod Committee of the Russian Social Democratic Labour Party. In 1906 he lived in Geneva, where he met with Vladimir Lenin.

In August 1907, Semashko served as a delegate from the Geneva Bolshevik organization at the International Socialist Congress of the Second International. The Swiss police arrested him after Olga Ravich, convicted in the case of the 1907 Tiflis expropriation, sent him a letter from prison. In 1908, together with the Bolshevik foreign center, he moved to Paris, where until 1910 he worked as secretary of the Foreign Bureau of the Central Committee of the RSDLP and participated in the Party School in Longjumeau. At the Sixth All-Russia Conference of the RSDLP Semashko delivered a report on the insurance sector, consisting of a draft resolution which Lenin had edited and which the Conference adopted. In 1913 Semashko participated in the social-democratic movement in Bulgaria. Returning to Moscow in September 1917, he was elected chairman of the Bolshevik faction of the Pyatnitskaya district council, he was a delegate of the Sixth Party Congress, participated in the preparation of the armed insurrection in Moscow, organized medical care for its participants.

After the October Revolution of November 1917, Semashko served as head of the Health Department of the Moscow City Council, from July 1918 to 1930 he held the post of Commissar of Health of the RSFSR. He directed the autopsy on Lenin's corpse. Under Semashko's leadership, work was carried out to combat epidemics, the foundations of Soviet public health were laid, a system of protection of motherhood and childhood and the health of children and adolescents and a network of medical research institutes were created. In 1921-1949 Semashko was a professor with the Chair of Social Hygiene in the medical faculty of Moscow State University. From 1930 to 1936, Semashko worked in the Central Executive Committee, where he served as a member of the Presidium and the chairman of the Commission for the Improvement of Children's Lives, entrusted with the fight against homelessness and the management of therapeutic and preventive work in children's health-facilities. In 1945-1949 he was Director of the Institute for School Health of the RSFSR, at the same time of the Institute for Health and History of Medicine of the Academy of Medical Sciences.

He was a founder of the Central Medical Library and of the House of Scientists in Moscow, editor-in-chief of the Great Medical Encyclopedia, the first chairman of the Supreme Council for Physical Education and Sports, chairman of the All-Union Hygiene Society, delegate to the 10th, 12th, 16th Party Congresses. He was awarded the Order of Lenin, the Order of the Red Banner of Labour, medals. Semashko was married and had a daughter Helen, for many years a responsible official of the Ministry of Health. Nikolai Aleksandrovich Semashko Archive Marxists Internet Archive Anna J. Haines, Dr. N. A. Semashko: The Commissar of Health