|
Takeo Nakasawa
Takeo Nakasawa ( ja, 中澤武雄, February 5, 1913, Kōchi prefecture, Japan – June 20, 1946, Khabarovsk, Soviet Union) was a Japanese mathematician who independently invented the theory of matroids, though his work was forgotten for many years. He published four papers (in German) of which the first three introduce the subject of matroid theory during 1935–1938, when he worked as an assistant in the Tokyo University of Arts and Sciences (now University of Tsukuba). After his last paper was published, he left for Manchuria at the age of 25 in 1938, then ruled by Japan, and worked as a bureaucrat there. With the defeat of Japan in 1945, the Soviets took control of Manchuria and Nakasawa was carted off to Siberia Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of .... He died of dyst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kōchi Prefecture
is a prefecture of Japan located on the island of Shikoku. Kōchi Prefecture has a population of 757,914 (1 December 2011) and has a geographic area of 7,103 km2 (2,742 sq mi). Kōchi Prefecture borders Ehime Prefecture to the northwest and Tokushima Prefecture to the northeast. Kōchi is the capital and largest city of Kōchi Prefecture, with other major cities including Nankoku, Shimanto, and Kōnan. Kōchi Prefecture is located on Japan's Pacific coast surrounding a large bay in the south of Shikoku, with the southernmost point of the island located at Cape Ashizuri in Tosashimizu. Kōchi Prefecture is home to Kōchi Castle, considered the most intact Japanese castle, and the Shimanto River, one of the few undammed rivers in Japan. History Kōchi Prefecture was historically known as Tosa Province and was controlled by the Chōsokabe clan in the Sengoku period and the Yamauchi clan during the Edo period. Kōchi city is also the birthplace of noted revolutiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north toward the East China Sea, Philippine Sea, and Taiwan in the south. Japan is a part of the Ring of Fire, and spans Japanese archipelago, an archipelago of List of islands of Japan, 6852 islands covering ; the five main islands are Hokkaido, Honshu (the "mainland"), Shikoku, Kyushu, and Okinawa Island, Okinawa. Tokyo is the Capital of Japan, nation's capital and largest city, followed by Yokohama, Osaka, Nagoya, Sapporo, Fukuoka, Kobe, and Kyoto. Japan is the List of countries and dependencies by population, eleventh most populous country in the world, as well as one of the List of countries and dependencies by population density, most densely populated and Urbanization by country, urbanized. About three-fourths of Geography of Japan, the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Khabarovsk
Khabarovsk ( rus, Хабaровск, a=Хабаровск.ogg, r=Habárovsk, p=xɐˈbarəfsk) is the largest types of inhabited localities in Russia, city and the administrative centre of Khabarovsk Krai, Russia,Law #109 located from the China–Russia border, at the confluence of the Amur River, Amur and Ussuri Rivers, about north of Vladivostok. With a Russian Census (2010), 2010 population of 577,441 it is Russia's easternmost city with more than half a million inhabitants. The city was the administrative center of the Far Eastern Federal District of Russia from 2002 until December 2018, when Vladivostok took over that role. It is the largest city in the Russian Far East, having overtaken Vladivostok in 2015. It was known as ''Khabarovka'' until 1893. As is typical of the interior of the Russian Far East, Khabarovsk has an #Climate, extreme climate with very strong seasonal swings resulting in strong cold winters and relatively hot and humid summers. History Earliest record ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk ( Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theory
A theory is a rational type of abstract thinking about a phenomenon, or the results of such thinking. The process of contemplative and rational thinking is often associated with such processes as observational study or research. Theories may be scientific, belong to a non-scientific discipline, or no discipline at all. Depending on the context, a theory's assertions might, for example, include generalized explanations of how nature works. The word has its roots in ancient Greek, but in modern use it has taken on several related meanings. In modern science, the term "theory" refers to scientific theories, a well-confirmed type of explanation of nature, made in a way consistent with the scientific method, and fulfilling the criteria required by modern science. Such theories are described in such a way that scientific tests should be able to provide empirical support for it, or empirical contradiction ("falsify") of it. Scientific theories are the most reliable, rigorous, and compr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matroid
In combinatorics, a branch of mathematics, a matroid is a structure that abstracts and generalizes the notion of linear independence in vector spaces. There are many equivalent ways to define a matroid axiomatically, the most significant being in terms of: independent sets; bases or circuits; rank functions; closure operators; and closed sets or flats. In the language of partially ordered sets, a finite matroid is equivalent to a geometric lattice. Matroid theory borrows extensively from the terminology of both linear algebra and graph theory, largely because it is the abstraction of various notions of central importance in these fields. Matroids have found applications in geometry, topology, combinatorial optimization, network theory and coding theory. Definition There are many equivalent ( cryptomorphic) ways to define a (finite) matroid.A standard source for basic definitions and results about matroids is Oxley (1992). An older standard source is Welsh (1976). See Brylawsk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History One of the earliest known mathematicians were Thales of Miletus (c. 624–c.546 BC); he has been hailed as the first true mathematician and the first known individual to whom a mathematical discovery has been attributed. He is credited with the first use of deductive reasoning applied to geometry, by deriving four corollaries to Thales' Theorem. The number of known mathematicians grew when Pythagoras of Samos (c. 582–c. 507 BC) established the Pythagorean School, whose doctrine it was that mathematics ruled the universe and whose motto was "All is number". It was the Pythagoreans who coined the term "mathematics", and with whom the study of mathematics for its own sake begins. The first woman mathematician recorded by history was Hypati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japanese People
The are an East Asian ethnic group native to the Japanese archipelago."人類学上は，旧石器時代あるいは縄文時代以来，現在の北海道〜沖縄諸島（南西諸島）に住んだ集団を祖先にもつ人々。" () Japanese people constitute 97.9% of the population of the country of Japan. Worldwide, approximately 129 million people are of Japanese descent; of these, approximately 122.5 million are residents of Japan. People of Japanese ancestry who live outside Japan are referred to as , the Japanese diaspora. Depending on the context, the term may be limited or not to mainland Japanese people, specifically the Yamato (as opposed to Ryukyuan and Ainu people). Japanese people are one of the largest ethnic groups in the world. In recent decades, there has also been an increase in the number of multiracial people with both Japanese and non-Japanese roots, including half Japanese people. History Theories of origins Archaeological evidence indi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History One of the earliest known mathematicians were Thales of Miletus (c. 624–c.546 BC); he has been hailed as the first true mathematician and the first known individual to whom a mathematical discovery has been attributed. He is credited with the first use of deductive reasoning applied to geometry, by deriving four corollaries to Thales' Theorem. The number of known mathematicians grew when Pythagoras of Samos (c. 582–c. 507 BC) established the Pythagorean School, whose doctrine it was that mathematics ruled the universe and whose motto was "All is number". It was the Pythagoreans who coined the term "mathematics", and with whom the study of mathematics for its own sake begins. The first woman mathematician recorded by history was Hypati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Tsukuba
is a public university, public research university located in Tsukuba, Ibaraki Prefecture, Ibaraki, Japan. It is a top 10 Designated National University, and was ranked Type A by the Japanese government as part of the Top Global University Project. The university has 28 college clusters and schools with around 16,500 students (as of 2014). The main Tsukuba campus covers an area of 258 hectares (636 acres), making it the second largest single campus in Japan. The university branch campus is in Bunkyō, Bunkyo-ku, Tokyo, offering graduate programs for working adults in the capital and managing K-12 schools in Tokyo that are attached to the university. Features The university is primarily focused on STEMM fields (Science, Technology, Engineering, Mathematics, Medicine), physical education, and related interdisciplinary fields. This focus is reflected by the university's location in the heart of Tsukuba Science City, alongside over 300 other research institutions. The univer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manchuria
Manchuria is an exonym (derived from the endo demonym " Manchu") for a historical and geographic region in Northeast Asia encompassing the entirety of present-day Northeast China (Inner Manchuria) and parts of the Russian Far East (Outer Manchuria). Its meaning may vary depending on the context: * Historical polities and geographical regions usually referred to as Manchuria: ** The Later Jin (1616–1636), the Manchu-led dynasty which renamed itself from "Jin" to "Qing", and the ethnicity from "Jurchen" to "Manchu" in 1636 ** the subsequent duration of the Qing dynasty prior to its conquest of China proper (1644) ** the northeastern region of Qing dynasty China, the homeland of Manchus, known as "Guandong" or "Guanwai" during the Qing dynasty ** The region of Northeast Asia that served as the historical homeland of the Jurchens and later their descendants Manchus ***Qing control of Dauria (the region north of the Amur River, but in its watershed) was contested in 1643 when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siberia
Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of Russia since the latter half of the 16th century, after the Russians conquered lands east of the Ural Mountains. Siberia is vast and sparsely populated, covering an area of over , but home to merely one-fifth of Russia's population. Novosibirsk, Krasnoyarsk and Omsk are the largest cities in the region. Because Siberia is a geographic and historic region and not a political entity, there is no single precise definition of its territorial borders. Traditionally, Siberia extends eastwards from the Ural Mountains to the Pacific Ocean, and includes most of the drainage basin of the Arctic Ocean. The river Yenisey divides Siberia into two parts, Western and Eastern. Siberia stretches southwards from the Arctic Ocean to the hills of north-ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
