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In geometry, a coordinate system is a system that uses one or more numbers, or coordinates, to uniquely determine the position of the points or other geometric elements on a manifold such as Euclidean space. The order of the coordinates is significant, and they are sometimes identified by their position in an ordered tuple and sometimes by a letter, as in "the x-coordinate". The coordinates are taken to be real numbers in elementary mathematics, but may be complex numbers or elements of a more abstract system such as a commutative ring. The use of a coordinate system allows problems in geometry to be translated into problems about numbers and vice versa; this is the basis of analytic geometry.
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David Pierre Ruelle is a Belgian mathematical physicist, naturalized French. He has worked on statistical physics and dynamical systems. With Floris Takens, Ruelle coined the term strange attractor, and developed a new theory of turbulence.
In fluid dynamics, the law of the wall states that the average velocity of a turbulent flow at a certain point is proportional to the logarithm of the distance from that point to the "wall", or the boundary of the fluid region. This law of the wall was first published in 1930 by Hungarian-American mathematician, aerospace engineer, and physicist Theodore von Kármán. It is only technically applicable to parts of the flow that are close to the wall, though it is a good approximation for the entire velocity profile of natural streams.
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Subhasish Dey is a hydraulician and educator. He is known for his research on the hydrodynamics and acclaimed for his contributions in developing theories and solution methodologies of various problems on hydrodynamics, turbulence, boundary layer, sediment transport and open channel flow. He is currently a distinguished professor of Indian Institute of Technology Jodhpur (2023–). Before, he worked as a professor of the department of civil engineering, Indian Institute of Technology Kharagpur (1998–2023), where he served as the head of the department during 2013–15 and held the position of Brahmaputra Chair Professor during 2009–14 and 2015. He also held the adjunct professor position in the Physics and Applied Mathematics Unit at Indian Statistical Institute Kolkata during 2014–19. Besides he has been named a distinguished visiting professor at the Tsinghua University in Beijing, China.
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This is a bibliography of works by Theodore von Kármán.
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Max Erich (Eric) Reissner was a German-American civil engineer and mathematician, and Professor of Mathematics at the Massachusetts Institute of Technology. He was recipient of the Theodore von Karman Medal in 1964, and the ASME Medal in 1988
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Albert Alan Townsend was an Australian scientist specialized in fluid dynamics. He was the author of the textbook The Structure of Turbulent Shear Flow. The terms Townsend's eddies(or Townsend's wall-attached eddies), Batchelor–Howells–Townsend spectrum and Townsend–Perry constants in turbulence research are named after him. His PhD advisor was G. I. Taylor and he was a close collaborator of George Batchelor.
References
- ↑ Taylor, G. I. (1935). Statistical theory of turbulence. Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, 151(873), 421-444.
- ↑ Monin, A. S., & Yaglom, A. M. (2013). Statistical fluid mechanics, volume II: Mechanics of turbulence (Vol. 2). Courier Corporation.
- ↑ Panchev, S. (2016). Random Functions and Turbulence: International Series of Monographs in Natural Philosophy (Vol. 32). Elsevier.
- ↑ Hinze, J. (1938). 0. 1975 Turbulence.
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