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Prony2
Prony or de Prony may refer to: * Gaspard de Prony (1755–1839), French mathematician and engineer ** Prony's method, a mathematical method to estimate the components of a signal ** Prony equation, hydraulics equation for fictional head loss ** Prony series, a model of viscoelasticity ** Prony brake, torque measurement device * Prony Bay, bay in New Caledonia * Prony, a city in New Caledonia, see List of cities in New Caledonia * French corvette ''Prony'' See also * Pronya The Pronya (russian: Проня) is a river in Ryazan and Tula Oblasts in Russia, a right tributary of the Oka. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prony's Method
Prony analysis (Prony's method) was developed by Gaspard Riche de Prony in 1795. However, practical use of the method awaited the digital computer. Similar to the Fourier transform, Prony's method extracts valuable information from a uniformly sampled signal and builds a series of damped complex exponentials or damped sinusoids. This allows for the estimation of frequency, amplitude, phase and damping components of a signal. The method Let f(t) be a signal consisting of N evenly spaced samples. Prony's method fits a function :\hat(t) = \sum_^ A_i e^ \cos(\omega_i t + \phi_i) to the observed f(t). After some manipulation utilizing Euler's formula, the following result is obtained. This allows more direct computation of terms. : \begin \hat(t) &= \sum_^ A_i e^ \cos(\omega_i t + \phi_i) \\ &= \sum_^ \frac A_i \left( e^e^ + e^e^\right) \end where: * \lambda^_i = \sigma_i \pm j \omega_i are the eigenvalues of the system, * \sigma_i = -\omega_ \xi_i are the damping c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaspard De Prony
Baron Gaspard Clair François Marie Riche de Prony (22 July 1755 – 29 July 1839) was a French mathematician and engineer, who worked on hydraulics. He was born at Chamelet, Beaujolais, France and died in Asnières-sur-Seine, France. Education and early works He was Engineer-in-Chief of the École Nationale des Ponts et Chaussées. The trigonometric and logarithmic tables of the cadastre In 1791, de Prony embarked on the task of producing logarithmic and trigonometric tables for the French Cadastre. The effort was sanctioned by the French National Assembly, which, after the French Revolution wanted to bring uniformity to the multiple measurements and standards used throughout the nation. In particular, his tables were intended for precise land surveys, as part of a greater cadastre effort. The tables were vast, calculating logarithms from 1 to 200,000, with values calculated to between fourteen and twenty-nine decimal places, (which de Prony recognized was excessive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prony Equation
The Prony equation (named after Gaspard de Prony) is a historically important equation in hydraulics, used to calculate the head loss due to friction within a given run of pipe. It is an empirical equation developed by Frenchman Gaspard de Prony in the 19th century: :h_f = \frac (aV + bV^2) where ''hf'' is the head loss due to friction, calculated from: the ratio of the length to diameter of the pipe ''L/D'', the velocity of the flow ''V'', and two empirical factors ''a'' and ''b'' to account for friction. This equation has been supplanted in modern hydraulics by the Darcy–Weisbach equation In fluid dynamics, the Darcy–Weisbach equation is an empirical equation that relates the head loss, or pressure loss, due to friction along a given length of pipe to the average velocity of the fluid flow for an incompressible fluid. The equation ..., which used it as a starting point. References *. The Prony equation and its replacement by the Darcy–Weisbach equation are on pp. 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscoelasticity
In materials science and continuum mechanics, viscoelasticity is the property of materials that exhibit both viscous and elastic characteristics when undergoing deformation. Viscous materials, like water, resist shear flow and strain linearly with time when a stress is applied. Elastic materials strain when stretched and immediately return to their original state once the stress is removed. Viscoelastic materials have elements of both of these properties and, as such, exhibit time-dependent strain. Whereas elasticity is usually the result of bond stretching along crystallographic planes in an ordered solid, viscosity is the result of the diffusion of atoms or molecules inside an amorphous material.Meyers and Chawla (1999): "Mechanical Behavior of Materials", 98-103. Background In the nineteenth century, physicists such as Maxwell, Boltzmann, and Kelvin researched and experimented with creep and recovery of glasses, metals, and rubbers. Viscoelasticity was further examin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prony Brake
The Prony Brake is a simple device invented by Gaspard de Prony in 1821 to measure the torque produced by an engine. The term "brake horsepower" is one measurement of power derived from this method of measuring torque. (Power is calculated by multiplying torque by rotational speed.) Essentially the measurement is made by wrapping a cord or belt around the output shaft of the engine and measuring the force transferred to the belt through friction. The friction is increased by tightening the belt until the frequency of rotation of the shaft is reduced to a desired rotational speed. In practice more engine power can then be applied until the limit of the engine is reached. In its simplest form an engine is connected to a rotating drum by means of an output shaft. A friction band is wrapped around half the drum's circumference and each end attached to a separate spring balance. A substantial pre-load is then applied to the ends of the band, so that each spring balance has an initi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prony Bay
Prony Bay or Baie de Prony is a bay of the southern end of New Caledonia. A number of small streams flow into the bay, including the Rivière Bleue and the Ruisseau de la Bergerie. Deposits of red clay increased between 1955 and 1968 due to extensive mining in the area. There are said to be oversized madrepore Madrepora (Spanish, "mother of pores") is a genus of stony corals, often found forming reefs or islands in tropical locations. The names Madrepore and Madreporaria were formerly applied universally to any stony coral of the family Scleractinia. T ... species growing in turbid waters, according to diving reports. References Bays of New Caledonia {{NewCaledonia-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Cities In New Caledonia
This article shows a list of cities, towns and villages in New Caledonia. Major cities and towns Provincial capitals are shown in bold. Hamlets (''Lieux-dits'') The villages or hamlets (french: lieux-dits) of New Caledonia are ordered by municipality (''commune'') and province. Municipal seats (''chef-lieu'') are shown in the list. South Province ---- * Bouloupari # Bouloupari (chef-lieu) # Bouraké #Gilles # Kouerga # Nassirah # Nétéa # Ouaméni # Ouinané # Ouitchambo # Tomo *Bourail Bourail is a commune in the South Province of New Caledonia, an overseas territory of France in the Pacific Ocean. Geography Bourail is a rural town of Grande Terre, New Caledonia's main island. The municipality stretches between the mount ... # Azareu # Bouirou # Gouaro # Nandaï # Néméara # Nessadiou # Ny #Oua-Oué #Potê *Dumbéa #Dumbéa (chef-lieu) #Koutio #Nondoué #Yahoué *Farino #Farino (chef-lieu) #Fonwhary *La Foa #La Foa (chef-lieu) #Coindé #Forêt Noire #Oua-T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French Corvette Prony
''Prony'' was a French Navy corvette warship during the American Civil War that ran aground and was lost off Ocracoke Inlet, North Carolina. It proved impossible to refloat the vessel, and efforts at assistance were hampered by both the weather and the fact that she had run aground in an area where Union and Confederate forces were opposing each other. History ''Prony'', a mixed sailing ship and steamer, was built in Brest from 1844 and launched in 1847 (Jacques Vichot, ''Répertoire des navires de guerre français'', 1967, p. 111). In 1854 it was sent to the South Seas along with a small fleet to claim possession of New Caledonia. Prony Bay is named after this ship. Loss ''Prony'' had left New York harbor on 20 October with the intention of observing as a neutral the activity of the Union Navy blockading the port of Charleston. She arrived off Charleston on 30 October, staying there for two days before heading north, intending to return to New York. She was caught in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
