|
Gerrit Lekkerkerker
Cornelis Gerrit Lekkerkerker (Harmelen, 7 February 1922 – 24 July 1999) was a Dutch mathematician. Education and career Lekkerkerker studied mathematics at Utrecht University during the periods 1940-1943 and 1945-1949 under Jurjen Koksma and Jan Popken. After completing his studies in 1949, he started work at the Amsterdam Centrum Wiskunde & Informatica (National Research Institute for Mathematics and Computer Science), where he worked under Koksma in the pure mathematics division. In the academic year 1953-1954, he studied in Rome. In 1955 he received his doctorate under the guidance of Popken with the thesis ''On the Zeros of a Class of Dirichlet-Series''; in Dutch: ''Over de nulpunten in een klasse van Dirichletreeksen''. Beginning in 1961, he was a professor at the University of Amsterdam, succeeding Nicolaas Govert de Bruijn. He was the director of the Mathematical Institute during the student protests of 1969-1973. In 1984, although he had not yet reached retirement age, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lekkerkerker
Lekkerkerker is a Dutch surname. Notable people with the surname include: * Brad Lekkerkerker (born 1978), American footballer * Cory Lekkerkerker (born 1981), former American footballer (younger brother of Brad Lekkerkerker) * Gerrit Lekkerkerker Cornelis Gerrit Lekkerkerker (Harmelen, 7 February 1922 – 24 July 1999) was a Dutch mathematician. Education and career Lekkerkerker studied mathematics at Utrecht University during the periods 1940-1943 and 1945-1949 under Jurjen Koksma and J ... (1922–1999), Dutch mathematician {{surname Dutch-language surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Physics
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter. Nuclear physics should not be confused with atomic physics, which studies the atom as a whole, including its electrons. Discoveries in nuclear physics have led to applications in many fields such as nuclear power, nuclear weapons, nuclear medicine and magnetic resonance imaging, industrial and agricultural isotopes, ion implantation in materials engineering, and radiocarbon dating in geology and archaeology. Such applications are studied in the field of nuclear engineering. Particle physics evolved out of nuclear physics and the two fields are typically taught in close association. Nuclear astrophysics, the application of nuclear physics to astrophysics, is crucial in explaining the inner workings of stars and the origin of the chemical elements. History The history of nuclear physics as a discipline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1999 Deaths
This is a list of lists of deaths of notable people, organized by year. New deaths articles are added to their respective month (e.g., Deaths in ) and then linked below. 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 1986 Earlier years ''Deaths in years earlier than this can usually be found in the main articles of the years.'' See also * Lists of deaths by day * Deaths by year (category) {{DEFAULTSORT:deaths by year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1922 Births
Events January * January 7 – Dáil Éireann (Irish Republic), Dáil Éireann, the parliament of the Irish Republic, ratifies the Anglo-Irish Treaty by 64–57 votes. * January 10 – Arthur Griffith is elected President of Dáil Éireann, the day after Éamon de Valera resigns. * January 11 – The first successful insulin treatment of diabetes is made, by Frederick Banting in Toronto. * January 15 – Michael Collins (Irish leader), Michael Collins becomes Chairman of the Provisional Government of the Irish Free State. * January 26 – Italian forces occupy Misrata, Italian Libya, Libya; the Pacification of Libya, reconquest of Libya begins. February * February 6 ** Pope Pius XI (Achille Ratti) succeeds Pope Benedict XV, to become the 259th pope. ** The Washington Naval Treaty, Five Power Naval Disarmament Treaty is signed between the United States, United Kingdom, Empire of Japan, Japan, French Third Republic, France and Kingdom of Italy, Italy. Japan returns some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Russian Language
Russian is an East Slavic languages, East Slavic language belonging to the Balto-Slavic languages, Balto-Slavic branch of the Indo-European languages, Indo-European language family. It is one of the four extant East Slavic languages, and is the native language of the Russians. It was the ''de facto'' and ''de jure'' De facto#National languages, official language of the former Soviet Union.1977 Soviet Constitution, Constitution and Fundamental Law of the Union of Soviet Socialist Republics, 1977: Section II, Chapter 6, Article 36 Russian has remained an official language of the Russia, Russian Federation, Belarus, Kazakhstan, Kyrgyzstan, and Tajikistan, and is still commonly used as a lingua franca in Ukraine, Moldova, the Caucasus, Central Asia, and to a lesser extent in the Baltic states and Russian language in Israel, Israel. Russian has over 253 million total speakers worldwide. It is the List of languages by number of speakers in Europe, most spoken native language in Eur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edouard Zeckendorf
Edouard Zeckendorf (2 May 1901 – 16 May 1983) was a Belgian doctor, army officer and amateur mathematician. In mathematics, he is best known for his work on Fibonacci numbers and in particular for proving Zeckendorf's theorem: every positive whole number is either a Fibonacci number or can be written as a sum of distinct non-consecutive Fibonacci numbers (and such a representation is unique). Early Life Zeckendorf was born in Liège in 1901. He was the son of Abraham Zeckendorf, Dutch dentist and practicing Jew. In 1925, Zeckendorf graduated as a medical doctor from the University of Liège and joined the Belgian Army medical corps. When Germany invaded Belgium in 1940, Zeckendorf was taken prisoner and remained a prisoner of war until 1945. During this period, he provided medical care to other allied POWs. Career When Germany invaded Belgium in 1940, Zeckendorf was taken prisoner and remained a prisoner of war until 1945. During this period, he provided medical care to o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibonacci Number
In mathematics, the Fibonacci sequence is a Integer sequence, sequence in which each element is the sum of the two elements that precede it. Numbers that are part of the Fibonacci sequence are known as Fibonacci numbers, commonly denoted . Many writers begin the sequence with 0 and 1, although some authors start it from 1 and 1 and some (as did Fibonacci) from 1 and 2. Starting from 0 and 1, the sequence begins : 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, ... The Fibonacci numbers were first described in Indian mathematics as early as 200 BC in work by Pingala on enumerating possible patterns of Sanskrit poetry formed from syllables of two lengths. They are named after the Italian mathematician Leonardo of Pisa, also known as Fibonacci, who introduced the sequence to Western European mathematics in his 1202 book . Fibonacci numbers appear unexpectedly often in mathematics, so much so that there is an entire journal dedicated to their study, the ''Fibonacci Quarterly''. Appli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeckendorf's Theorem
In mathematics, Zeckendorf's theorem, named after Belgian amateur mathematician Edouard Zeckendorf, is a theorem about the representation of integers as sums of Fibonacci numbers. Zeckendorf's theorem states that every positive integer can be represented uniquely as the sum of ''one or more'' distinct Fibonacci numbers in such a way that the sum does not include any two consecutive Fibonacci numbers. More precisely, if is any positive integer, there exist positive integers , with , such that :N = \sum_^k F_, where is the th Fibonacci number. Such a sum is called the Zeckendorf representation of . The Fibonacci coding of can be derived from its Zeckendorf representation. For example, the Zeckendorf representation of 64 is :. There are other ways of representing 64 as the sum of Fibonacci numbers : : : : but these are not Zeckendorf representations because 34 and 21 are consecutive Fibonacci numbers, as are 5 and 3. For any given positive integer, its Zeckendorf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coding Theory
Coding theory is the study of the properties of codes and their respective fitness for specific applications. Codes are used for data compression, cryptography, error detection and correction, data transmission and computer data storage, data storage. Codes are studied by various scientific disciplines—such as information theory, electrical engineering, mathematics, linguistics, and computer science—for the purpose of designing efficient and reliable data transmission methods. This typically involves the removal of redundancy and the correction or detection of errors in the transmitted data. There are four types of coding: # Data compression (or ''source coding'') # Error detection and correction, Error control (or ''channel coding'') # Cryptography, Cryptographic coding # Line code, Line coding Data compression attempts to remove unwanted redundancy from the data from a source in order to transmit it more efficiently. For example, DEFLATE data compression makes files small ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topology
Topology (from the Greek language, Greek words , and ) is the branch of mathematics concerned with the properties of a Mathematical object, geometric object that are preserved under Continuous function, continuous Deformation theory, deformations, such as Stretch factor, stretching, Torsion (mechanics), twisting, crumpling, and bending; that is, without closing holes, opening holes, tearing, gluing, or passing through itself. A topological space is a Set (mathematics), set endowed with a structure, called a ''Topology (structure), topology'', which allows defining continuous deformation of subspaces, and, more generally, all kinds of List of continuity-related mathematical topics, continuity. Euclidean spaces, and, more generally, metric spaces are examples of topological spaces, as any distance or metric defines a topology. The deformations that are considered in topology are homeomorphisms and Homotopy, homotopies. A property that is invariant under such deformations is a to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graph Theory
In mathematics and computer science, graph theory is the study of ''graph (discrete mathematics), graphs'', which are mathematical structures used to model pairwise relations between objects. A graph in this context is made up of ''Vertex (graph theory), vertices'' (also called ''nodes'' or ''points'') which are connected by ''Glossary of graph theory terms#edge, edges'' (also called ''arcs'', ''links'' or ''lines''). A distinction is made between undirected graphs, where edges link two vertices symmetrically, and directed graphs, where edges link two vertices asymmetrically. Graphs are one of the principal objects of study in discrete mathematics. Definitions Definitions in graph theory vary. The following are some of the more basic ways of defining graphs and related mathematical structures. Graph In one restricted but very common sense of the term, a graph is an ordered pair G=(V,E) comprising: * V, a Set (mathematics), set of vertices (also called nodes or points); * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argonne National Laboratory
Argonne National Laboratory is a Federally funded research and development centers, federally funded research and development center in Lemont, Illinois, Lemont, Illinois, United States. Founded in 1946, the laboratory is owned by the United States Department of Energy and administered by UChicago Argonne LLC of the University of Chicago. The facility is the largest national laboratory in the Midwestern United States, Midwest. Argonne had its beginnings in the Metallurgical Laboratory of the University of Chicago, formed in part to carry out Enrico Fermi's work on nuclear reactors for the Manhattan Project during World War II. After the war, it was designated as the first national laboratory in the United States on July 1, 1946. In its first decades, the laboratory was a hub for peaceful use of nuclear physics; nearly all operating commercial nuclear power plants around the world have roots in Argonne research. More than 1,000 scientists conduct research at the laboratory, in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
