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31.
光盘用光学头物镜性能的综合评估   总被引:1,自引:0,他引:1  
杨勋  曾吉勇 《光电工程》1994,21(2):49-52
论述了采用波象差均方根、点扩展函数、光学传递函数对高次旋转对称非球面光学头物镜性能进行综合评估的方法。作者在正则坐标理论基础〔1〕上编制了光学头物镜性能综合评估软件。给出了评估实例。  相似文献   
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Determining contributions of source-monitoring and inhibitory function to age-related forgetting has been an elusive goal for cognitive theorists. Five studies used a verbal working memory paradigm to examine mechanisms accounting for disproportionate retroactive interference (RI) experienced with adult aging. Participants distinguished studied target-word pairs from interfering pairs that were read aloud. Source-monitoring and inhibitory task components varied through manipulations of response requirements. RI effects were primarily due to source-monitoring failures rather than to inhibitory failures. Removing both source and inhibitory components eliminated age differences in RI. When source monitoring was emphasized, RI continued to be observed in all age groups but disproportionately for older adults. Process dissociation analyses of memory found recollection decreases and familiarity increases consistent with source failures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
An approach to solving a linear interpolation problem in a fuzzy information space is proposed. Two different schemes of interpolation are outlined: a heuristic one, based on the geometrical interpretation of operations, and an optimization one, based on the expansion principle. The results obtained allow performing fuzzy linear prediction. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 55–68, March–April 2006.  相似文献   
35.
关于布尔函数的二次逼近   总被引:2,自引:0,他引:2  
本文首先利用矩阵形式引入了二阶walsh谱的概念并讨论了其性质,其次引入了二次bent函数的概念,同时论述了二次bent函数的密码学意义。  相似文献   
36.
运用韦柏函数分析发动机燃烧过程时若干问题的探讨   总被引:1,自引:0,他引:1  
探讨了韦柏函数的内涵及其在实际应用中的若干问题;应用双韦柏函数对涡流室式柴油机的燃烧过程进行分析,加深了对分隔室式发动机燃烧过程的认识.  相似文献   
37.
Experimental data for the densities, dynamic viscosities, sound speeds, and relative permittivities and for three binary systems of methyl methacrylate (MMA)+di-ethers (ethyl, isopropyl, and butyl) at 298.15 and 308.15 K and at atmospheric pressure are reported. The mixture viscosities are correlated by Grunberg–Nissan, McAllister, and Auslander equations over the complete composition range. The sound speeds for the mixtures are also calculated by using free length and collision factor theories, and Nomoto and Junjie equations. From the measured primary properties, deviation functions such as deviations in viscosities, sound speeds, relative permittivities, molar polarizations, excess isentropic compressibilities, and molar electrical susceptibilities were calculated, and the compositional dependence of each of the functions was expressed with a Redlich–Kister type equation. The variation of the Kirkwood correlation factor was determined over the complete composition range.  相似文献   
38.
This paper presents an exact non‐reflecting boundary condition for dealing with transient scalar wave propagation problems in a two‐dimensional infinite homogeneous layer. In order to model the complicated geometry and material properties in the near field, two vertical artificial boundaries are considered in the infinite layer so as to truncate the infinite domain into a finite domain. This treatment requires the appropriate boundary conditions, which are often referred to as the artificial boundary conditions, to be applied on the truncated boundaries. Since the infinite extension direction is different for these two truncated vertical boundaries, namely one extends toward x →∞ and another extends toward x→‐ ∞, the non‐reflecting boundary condition needs to be derived on these two boundaries. Applying the variable separation method to the wave equation results in a reduction in spatial variables by one. The reduced wave equation, which is a time‐dependent partial differential equation with only one spatial variable, can be further changed into a linear first‐order ordinary differential equation by using both the operator splitting method and the modal radiation function concept simultaneously. As a result, the non‐reflecting artificial boundary condition can be obtained by solving the ordinary differential equation whose stability is ensured. Some numerical examples have demonstrated that the non‐reflecting boundary condition is of high accuracy in dealing with scalar wave propagation problems in infinite and semi‐infinite media. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
39.
本文从紧凑式轧机的轧制变形特点出发,分析了其变形规程设计的主要特点和方法,讨论了限制其道次变形量的基本因素,给出了优化设计的目标函数和约束条件。指出,类似这种具有复杂约束的轧制变形问题采用混合罚函数法处理更为有效,并成功地采用该方法进行了变形规程的试设定。  相似文献   
40.
坐标旋转法的收敛性,误差估计及扩展   总被引:1,自引:0,他引:1  
本文通过推广正规序列的定义,得到一个不等式,由此证明了统一计算初等函数数值的坐标旋转法的收敛性,作了误差估计,并拓广了所计算的函数范围,成为快速计算所有初等函数的统一算法.  相似文献   
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