Issac Koga
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Issac Koga
was an inventor and scientist. Early life and education He was the eldest of seven children born in Tashiro Village (now Tosu), Saga Prefecture. In July 1920, at the age of 20, he started to study at the Department of Electrical Engineering at Tokyo Imperial University (later renamed University of Tokyo). After graduation in August 1925, he moved to the new Tokyo City Electrical Institute, which was established to develop and promote radio broadcasting technology under the directorship of Kotaro Kujirai, a pioneer of the research and teaching of radio science. Initially an engineer, he became an assistant professor in 1929. Under the guidance of Professor Kujirai, he studied crystal oscillators. This formed the basis of his PhD thesis, completed in April 1930, entitled "Characteristics of the Crystal Oscillator." This work included making the first quartz tuning forks in 1927. In 1929, he became an associate professor at the Tokyo Institute of Technology and a professor in ...
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Tosu, Saga
is a Cities of Japan, city located in the eastern part of Saga Prefecture on the island of Kyushu, Japan. As of February 28, 2017, the city has an estimated population of 72,755 and a population density of 1,000 persons per km2. The total area is 71.73 km2. Overview Tosu is one of the major transportation hubs of Kyushu. Its main train station is Tosu Station which connects the Nagasaki Main Line and the Kagoshima Main Line. There is also a Interchange (road), junction connecting the Kyūshū Expressway, Nagasaki Expressway and Ōita Expressway. Economically it is part of the Fukuoka, Fukuoka, Fukuoka metropolitan area, and according to a 2000 census about 5% of the total population of Tosu commute to work or school in Fukuoka. Geography Located in the Saga Plains, the Chikushi River runs along the southern border of Tosu. The lowlands are used for paddy farming and are where the city center is located. The northwestern part of the city contains the eastern part of the Se ...
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University Of Tokyo
, abbreviated as or UTokyo, is a public research university located in Bunkyō, Tokyo, Japan. Established in 1877, the university was the first Imperial University and is currently a Top Type university of the Top Global University Project by the Japanese government. UTokyo has 10 faculties, 15 graduate schools and enrolls about 30,000 students, about 4,200 of whom are international students. In particular, the number of privately funded international students, who account for more than 80%, has increased 1.75 times in the 10 years since 2010, and the university is focusing on supporting international students. Its five campuses are in Hongō, Komaba, Kashiwa, Shirokane and Nakano. It is considered to be the most selective and prestigious university in Japan. As of 2021, University of Tokyo's alumni, faculty members and researchers include seventeen prime ministers, 18 Nobel Prize laureates, four Pritzker Prize laureates, five astronauts, and a Fields Medalist. Hist ...
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Crystal Oscillator
A crystal oscillator is an electronic oscillator circuit that uses a piezoelectric crystal as a frequency-selective element. The oscillator frequency is often used to keep track of time, as in quartz wristwatches, to provide a stable clock signal for digital integrated circuits, and to stabilize frequencies for radio transmitters and receivers. The most common type of piezoelectric resonator used is a quartz crystal, so oscillator circuits incorporating them became known as crystal oscillators. However, other piezoelectricity materials including polycrystalline ceramics are used in similar circuits. A crystal oscillator relies on the slight change in shape of a quartz crystal under an electric field, a property known as inverse piezoelectricity. A voltage applied to the electrodes on the crystal causes it to change shape; when the voltage is removed, the crystal generates a small voltage as it elastically returns to its original shape. The quartz oscillates at a stable ...
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PhD Thesis
A thesis ( : theses), or dissertation (abbreviated diss.), is a document submitted in support of candidature for an academic degree or professional qualification presenting the author's research and findings.International Standard ISO 7144: DocumentationPresentation of theses and similar documents International Organization for Standardization, Geneva, 1986. In some contexts, the word "thesis" or a cognate is used for part of a bachelor's or master's course, while "dissertation" is normally applied to a doctorate. This is the typical arrangement in American English. In other contexts, such as within most institutions of the United Kingdom and Republic of Ireland, the reverse is true. The term graduate thesis is sometimes used to refer to both master's theses and doctoral dissertations. The required complexity or quality of research of a thesis or dissertation can vary by country, university, or program, and the required minimum study period may thus vary significantly in dur ...
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Quartz Crystal
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classified as gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Eurasia. Quartz is the mineral defining the valu ...
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Japanese Telecommunications Engineers
Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspora, Japanese emigrants and their descendants around the world * Japanese citizens, nationals of Japan under Japanese nationality law ** Foreign-born Japanese, naturalized citizens of Japan * Japanese writing system, consisting of kanji and kana * Japanese cuisine, the food and food culture of Japan See also * List of Japanese people * * Japonica (other) * Japonicum * Japonicus * Japanese studies Japanese studies (Japanese: ) or Japan studies (sometimes Japanology in Europe), is a sub-field of area studies or East Asian studies involved in social sciences and humanities research on Japan. It incorporates fields such as the study of Japanese ... {{disambiguation Language and nationality disambiguation pages ...
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Japanese Electronics Engineers
Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspora, Japanese emigrants and their descendants around the world * Japanese citizens, nationals of Japan under Japanese nationality law ** Foreign-born Japanese, naturalized citizens of Japan * Japanese writing system, consisting of kanji and kana * Japanese cuisine, the food and food culture of Japan See also * List of Japanese people * * Japonica (other) * Japonicum * Japonicus * Japanese studies Japanese studies (Japanese: ) or Japan studies (sometimes Japanology in Europe), is a sub-field of area studies or East Asian studies involved in social sciences and humanities research on Japan. It incorporates fields such as the study of Japanese ... {{disambiguation Language and nationality disambiguation pages ...
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1899 Births
Events January 1899 * January 1 ** Spanish rule ends in Cuba, concluding 400 years of the Spanish Empire in the Americas. ** Queens and Staten Island become administratively part of New York City. * January 2 – **Bolivia sets up a customs office in Puerto Alonso, leading to the Brazilian settlers there to declare the Republic of Acre in a revolt against Bolivian authorities. **The first part of the Jakarta Kota–Anyer Kidul railway on the island of Java is opened between Batavia Zuid ( Jakarta Kota) and Tangerang. * January 3 – Hungarian Prime Minister Dezső Bánffy fights an inconclusive duel with his bitter enemy in parliament, Horánszky Nándor. * January 4 – **U.S. President William McKinley's declaration of December 21, 1898, proclaiming a policy of benevolent assimilation of the Philippines as a United States territory, is announced in Manila by the U.S. commander, General Elwell Otis, and angers independence activists who had fought against ...
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