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151.
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强度调制型光纤传感器信号补偿技术的现状与应用 总被引:8,自引:2,他引:6
简要地介绍了强度调制光纤传感器的特点,着重分析和比较目前国内外五种有代表性的强度调制型光纤传感器信号补偿方法及其应用状况. 相似文献
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To acquire maximum information on the geometrical errors of industrially made surfaces at a minimum cost, a method for estimating conditional probabilities of a random signal (Bayesian prediction) is applied to three-dimensional metrology. First, a surface is interpolated between data acquired on a coordinate measuring machine (CMM). Then, for a given probability, limit surfaces are computed that bind a region of space containing the known data and the most probable interpolation of the missing data of the surface. These bounds can be treated as the surface; their points can be considered as if they were actual CMM data when fitting a tolerance zone or a datum feature to the data. For Bayesian prediction, the basic hypotheses on the signal are stationarity, ergodicity, and gaussian density. Deviations from these hypotheses and their consequences on the prediction are taken into account and corrections are proposed. 相似文献
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Aeromagnetic compensation using neural networks 总被引:1,自引:0,他引:1
Peter M. Williams 《Neural computing & applications》1993,1(3):207-214
Airborne magnetic surveys in geophysical exploration can be subject to interference effects from the aircraft. Principal sources are the permanent magnetism of various parts of the aircraft, induction effects created by the earth's magnetic field and eddy-current fields produced by the aircraft's manoeuvres. Neural networks can model these effects as functions of roll, pitch, heading and their time derivatives, together with vertical acceleration, charging currents to the generator, etc., without assuming an explicit physical model. Separation of interference effects from background regional and diurnal fields can also be achieved in a satisfactory way. 相似文献
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Akira Ishizaki Kazuhiko Takasaki Shoji Shimomura Kouichi Masaki Kanji Kitazawa 《Electrical Engineering in Japan》1996,116(5):128-137
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy. 相似文献
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本文考虑了数性双曲方程的离散Galerkin方法。如果精确到光滑的并且同是几乎均匀的,证明了对于分层常数元的最优的和超收敛的误差限。 相似文献