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81.
狭缝式高速摄影机胶片的计算机判读   总被引:3,自引:1,他引:2  
根据狭缝摄影机胶片的成象原理,运用数字图象处理技术,对狭缝式高速摄影机胶片判读工作的计算机化进行研究.应用结果表明,该技术先进实用,极大地提高了判读的精度和效率,将是这种胶片判读技术的发展方向.  相似文献   
82.
A method is formulated for the identification of an unknown physical parameter of a fluid-filled pipe using the measurement of sound speed in the pipe. The method uses a simple formula which provides the relationship between the sound speed and a few physical parameters of the pipe: thickness, diameter, wall material constants and fluid constants. Once the sound speed in the pipe is measured, the simple formula can be used to extract one of the unknown parameters providing the remaining ones are known.The sound speed in the pipe is measured using a 3-transducer array. In order to demonstrate the potential of the technique the results of several measurements obtained in a water-filled steel pipe are presented.The required accuracy of the measurement of sound speed and of the specification of known parameters is analysed. The accuracy depends on the unknown parameter which is to be identified. For example, if the pipe thickness is the unknown parameter, the other parameters have to be known within a very narrow margin of error. On the contrary, if the fluid properties have to be identified the needed accuracy of known parameters gets much lower.  相似文献   
83.
The reactions of ethylene glycol mononitrate and glycerol 1,3-dinitrate with methylphosphonic dichloride afforded new nitroxyalkyl methylphosphonates.  相似文献   
84.
运用中学生男性性别角色期望调查表和因子分析方法对贵阳市中学生进行男性性别角色期望调查和定性与定量分析,为中学生树立适宜的性别角色观,促进其心理健康发展提供量化依据.分析显示:传统的男性角色并不被现代中学生完全接受,无论是男中学生还是女中学生都在力图探求一种新的男性性别角色模式,且两性中学生对这一新的男性性别角色模式的期望和把握是有一定差异的.  相似文献   
85.
Numerical solutions to three systems of integrable evolutionary equations from the Toda lattice hierarchy are analyzed. These are the classical Toda lattice, the second local dispersive flow, and the second extended dispersive flow. Special attention is given to the properties of soliton solutions. For the equations of the second local flow, two types of solitons interacting in a special manner are found. Solutions corresponding to various initial data are qualitatively outlined.  相似文献   
86.
The prepared amorphous γ-ZrP\SiO2 composite had a complicated composition, since a part of γ-ZrP is converted to α-form during the exfoliation of it. The γ-ZrP\SiO2 composite have specific surface area of 421 m2g–1. The acidic P–OH groups of the lamellae species placed on the surface (it is ≈1.0 meq g–1), do not destroy until the temperature of 1030 K. During the thermal treatment the total mass loss of 7.79% was found. This value corresponds to 0.42 mole of H2O per molecule unit. The water loss process was found very slow, because of the placing of bilamellar species in the composite.  相似文献   
87.
Many Ligularia species have long been used as traditional folk medicine for theirantibiotic, antiphlogistic and antitussive activities1, and were found to be an importantsource of eremophilane. In the course of our search for bioactive sesquiterpenoids, w…  相似文献   
88.
89.
In this paper we study Clifford and harmonic analysis on some examples of conformal flat manifolds that have a spinor structure, or more generally, at least a pin structure. The examples treated here are manifolds that can be parametrized by U/Γ where U is a subdomain of either Sn or Rn and Γ is a Kleinian group acting discontinuously on U. The examples studied here include RPn and the Hopf manifolds S1×Sn−1. Also some hyperbolic manifolds will be treated. Special kinds of Clifford-analytic automorphic forms associated to the different choices of Γ are used to construct explicit Cauchy kernels, Cauchy integral formulas, Green's kernels and formulas together with Hardy spaces and Plemelj projection operators for Lp spaces of hypersurfaces lying in these manifolds.  相似文献   
90.
Canonical correlation analysis based on information theory   总被引:2,自引:0,他引:2  
In this article, we propose a new canonical correlation method based on information theory. This method examines potential nonlinear relationships between p×1 vector Y-set and q×1 vector X-set. It finds canonical coefficient vectors a and b by maximizing a more general measure, the mutual information, between aTX and bTY. We use a permutation test to determine the pairs of the new canonical correlation variates, which requires no specific distributions for X and Y as long as one can estimate the densities of aTX and bTY nonparametrically. Examples illustrating the new method are presented.  相似文献   
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