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Emanuels Grīnbergs
Emanuels Donats Frīdrihs Jānis Grinbergs (1911–1982, westernized as Emanuel Grinberg) was a Latvian mathematician, known for Grinberg's theorem on the Hamiltonicity of planar graphs.... Biography Grinbergs was born on January 25, 1911, in St. Petersburg, the son of a Lutheran bishop from Latvia. Latvia became independent from Russia in 1917, and on the death of his father in 1923, Grinbergs' family returned to Riga, taking Grinbergs with them. In 1927, he won a high school mathematics competition, the prize for which was to study in Lille, France. He then studied mathematics at the University of Latvia beginning in 1930. On graduating in 1934, he won a prize that again funded study in France; he did graduate studies in 1935 and 1936 at the École Normale Supérieure in Paris, during which he published his first paper, in geometry. He returned to the University of Latvia as a ''privatdozent'' in 1937, and joined the faculty as a dozent in 1940. His lectures at that time cover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latvia
Latvia ( or ; lv, Latvija ; ltg, Latveja; liv, Leţmō), officially the Republic of Latvia ( lv, Latvijas Republika, links=no, ltg, Latvejas Republika, links=no, liv, Leţmō Vabāmō, links=no), is a country in the Baltic region of Northern Europe. It is one of the Baltic states; and is bordered by Estonia to the north, Lithuania to the south, Russia to the east, Belarus to the southeast, and shares a maritime border with Sweden to the west. Latvia covers an area of , with a population of 1.9 million. The country has a temperate seasonal climate. Its capital and largest city is Riga. Latvians belong to the ethno-linguistic group of the Balts; and speak Latvian, one of the only two surviving Baltic languages. Russians are the most prominent minority in the country, at almost a quarter of the population. After centuries of Teutonic, Swedish, Polish-Lithuanian and Russian rule, which was mainly executed by the local Baltic German aristocracy, the independent R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group Theory
In abstract algebra, group theory studies the algebraic structures known as group (mathematics), groups. The concept of a group is central to abstract algebra: other well-known algebraic structures, such as ring (mathematics), rings, field (mathematics), fields, and vector spaces, can all be seen as groups endowed with additional operation (mathematics), operations and axioms. Groups recur throughout mathematics, and the methods of group theory have influenced many parts of algebra. Linear algebraic groups and Lie groups are two branches of group theory that have experienced advances and have become subject areas in their own right. Various physical systems, such as crystals and the hydrogen atom, and Standard Model, three of the four known fundamental forces in the universe, may be modelled by symmetry groups. Thus group theory and the closely related representation theory have many important applications in physics, chemistry, and materials science. Group theory is also ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Mathematical Society
The American Mathematical Society (AMS) is an association of professional mathematicians dedicated to the interests of mathematical research and scholarship, and serves the national and international community through its publications, meetings, advocacy and other programs. The society is one of the four parts of the Joint Policy Board for Mathematics and a member of the Conference Board of the Mathematical Sciences. History The AMS was founded in 1888 as the New York Mathematical Society, the brainchild of Thomas Fiske, who was impressed by the London Mathematical Society on a visit to England. John Howard Van Amringe was the first president and Fiske became secretary. The society soon decided to publish a journal, but ran into some resistance, due to concerns about competing with the American Journal of Mathematics. The result was the ''Bulletin of the American Mathematical Society'', with Fiske as editor-in-chief. The de facto journal, as intended, was influential in in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamiltonian Cycle
In the mathematical field of graph theory, a Hamiltonian path (or traceable path) is a path in an undirected or directed graph that visits each vertex exactly once. A Hamiltonian cycle (or Hamiltonian circuit) is a cycle that visits each vertex exactly once. A Hamiltonian path that starts and ends at adjacent vertices can be completed by adding one more edge to form a Hamiltonian cycle, and removing any edge from a Hamiltonian cycle produces a Hamiltonian path. Determining whether such paths and cycles exist in graphs (the Hamiltonian path problem and Hamiltonian cycle problem) are NP-complete. Hamiltonian paths and cycles are named after William Rowan Hamilton who invented the icosian game, now also known as ''Hamilton's puzzle'', which involves finding a Hamiltonian cycle in the edge graph of the dodecahedron. Hamilton solved this problem using the icosian calculus, an algebraic structure based on roots of unity with many similarities to the quaternions (also invented by Hami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spline Curve
In mathematics, a spline is a special function defined piecewise by polynomials. In interpolating problems, spline interpolation is often preferred to polynomial interpolation because it yields similar results, even when using low degree polynomials, while avoiding Runge's phenomenon for higher degrees. In the computer science subfields of computer-aided design and computer graphics, the term ''spline'' more frequently refers to a piecewise polynomial ( parametric) curve. Splines are popular curves in these subfields because of the simplicity of their construction, their ease and accuracy of evaluation, and their capacity to approximate complex shapes through curve fitting and interactive curve design. The term spline comes from the flexible spline devices used by shipbuilders and draftsmen to draw smooth shapes. Introduction The term "spline" is used to refer to a wide class of functions that are used in applications requiring data interpolation and/or smoothing. The data m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Filter
Electronic filters are a type of signal processing filter in the form of electrical circuits. This article covers those filters consisting of lumped electronic components, as opposed to distributed-element filters. That is, using components and interconnections that, in analysis, can be considered to exist at a single point. These components can be in discrete packages or part of an integrated circuit. Electronic filters remove unwanted frequency components from the applied signal, enhance wanted ones, or both. They can be: *passive or active *analog or digital *high-pass, low-pass, band-pass, band-stop (band-rejection; notch), or all-pass. *discrete-time (sampled) or continuous-time *linear or non-linear *infinite impulse response (IIR type) or finite impulse response (FIR type) The most common types of electronic filters are linear filters, regardless of other aspects of their design. See the article on linear filters for details on their design and analysis. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grinberg 5CEC Nonhamiltonian Graph
Grinberg is a surname and Yiddish variant of Grünberg, literally "green mountain" in German. Notable people with the surname include: * Adam Greenberg (cinematographer) (born 1939), Polish cinematographer *Alexander Grinberg, Soviet photographer * Anouk Grinberg (born 1963), Belgian actor * Emanuel Grinberg (1911–1982), Latvian mathematician ** Grinberg's theorem, named after Emanuel Grinberg * Gedalio Grinberg (1931–2009), Cuban-American watchmaker * Iosif Grinberg (1906–1980), Soviet literary critic *Ivan Grinberg (1908–1973), birth name of Philip Rahv *Jacques Grinberg (1941-2011), neo-expressionist painter and printmaker * Linda Grinberg (1951–2002), American HIV/AIDS activist * Maria Grinberg (1908–1978), Soviet pianist *Ricardo Grinberg (born 1948), Argentine chess master *Sara Topelson de Grinberg (born 1945), Polish-born Mexican architect *Yoysef Grinberg (1900–1996), Polish-born American actor *Zalman Grinberg (1912–1983), American physician See also *Gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latvian Academy Of Sciences
The Latvian Academy of Sciences ( lv, Latvijas Zinātņu akadēmija) is the official Academy of Sciences, science academy of Latvia and is an association of the country's foremost scientists. The academy was founded as the ''Latvian SSR Academy of Sciences'' ( lv, Latvijas PSR Zinātņu akadēmija). It is located in Riga. The current President of the academy is Ivars Kalviņš. Building The Academy of Sciences edifice was built after World War II, between 1951 and 1961, collecting the necessary financing from the newly established kolkhozes in Latvia and – as further expenses increased, collecting the finances as "voluntary donations" deducted from the salaries of the Latvian rural population. The building is decorated with several Hammer and Sickle, hammer and sickle symbols as well as Latvian folk ornaments and motifs. The spire was originally decorated with a wreath and a Red star, five pointed star, which was removed after Latvia regained independence in 1991. Being tall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Candidate Of Sciences
Candidate of Sciences (russian: кандидат наук, translit=kandidat nauk) is the first of two doctoral level scientific degrees in Russia and the Commonwealth of Independent States. It is formally classified as UNESCO's ISCED level 8, "doctoral or equivalent". It may be recognized as Doctor of Philosophy, usually in natural sciences, by scientific institutions in other countries. Former Soviet countries also have a more advanced degree, Doctor of Sciences. Overview The degree was first introduced in the USSR on 13 January 1934 by a decision of the Council of People's Commissars of the USSR, all previous degrees, ranks and titles having been abolished immediately after the October Revolution in 1917. Academic distinctions and ranks were viewed as survivals of capitalist inequality and hence were to be permanently eliminated. The original decree also recognized some degrees earned prior to 1917 in Tsarist Russia and elsewhere. To attain the Candidate of Sciences de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgia (country)
Georgia (, ; ) is a transcontinental country at the intersection of Eastern Europe and Western Asia. It is part of the Caucasus region, bounded by the Black Sea to the west, by Russia to the north and northeast, by Turkey to the southwest, by Armenia to the south, and by Azerbaijan to the southeast. The country covers an area of , and has a population of 3.7 million people. Tbilisi is its capital as well as its largest city, home to roughly a third of the Georgian population. During the classical era, several independent kingdoms became established in what is now Georgia, such as Colchis and Iberia. In the early 4th century, ethnic Georgians officially adopted Christianity, which contributed to the spiritual and political unification of the early Georgian states. In the Middle Ages, the unified Kingdom of Georgia emerged and reached its Golden Age during the reign of King David IV and Queen Tamar in the 12th and early 13th centuries. Thereafter, the kingdom decl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kutaisi
Kutaisi (, ka, ქუთაისი ) is one of the oldest continuously inhabited cities in the world and the third-most populous city in Georgia, traditionally, second in importance, after the capital city of Tbilisi. Situated west of Tbilisi, on the Rioni River, it is the capital of the western region of Imereti. Historically one of the major cities of Georgia, it served as political center of Colchis in the Middle Ages as capital of the Kingdom of Abkhazia and Kingdom of Georgia and later as the capital of the Kingdom of Imereti. From October 2012 to December 2018, Kutaisi was the seat of the Parliament of Georgia as an effort to decentralise the Georgian government. History Archaeological evidence indicates that the city functioned as the capital of the Colchis in the sixth to fifth centuries BC. It is believed that, in ''Argonautica'', a Greek epic poem about Jason and the Argonauts and their journey to Colchis, author Apollonius Rhodius considered Kutaisi their final d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latvian Legion
The Latvian Legion ( lv, Latviešu leģions) was a formation of the German Waffen-SS during World War II. Created in 1943, it consisted primarily of ethnic Latvian personnel.Gerhard P. Bassler, ''Alfred Valdmanis and the politics of survival'', 2000, p150 Mirdza Kate Baltais, ''The Latvian Legion in documents'', 1999, p14 The legion consisted of two divisions of the Waffen-SS: the 15th Waffen Grenadier Division of the SS (1st Latvian), and the 19th Waffen Grenadier Division of the SS (2nd Latvian). The 15th Division was administratively subordinated to the VI SS Corps, but operationally it was in reserve or at the disposal of the XXXXIII Army Corps, 16th Army, Army Group North. The 19th Division held out in the Courland Pocket until May 1945, the close of World War II, when it was among the last of Nazi Germany's forces to surrender. Creation The Latvian Legion was created in January 1943 on the orders of Adolf Hitler following a request by Heinrich Himmler, the head of the S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
