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991.
徐金利  曹重光 《数学研究》2007,40(2):207-210
设F是一个特征2且至少含有5个元素的域,n≥2是一个正整数.令Mn(F)和Tn(F)分别F上的全矩阵空间和上三角矩阵空间.我们首先刻划从Tn(F)到Mn(F)的保矩阵群逆的所有线性单射,由此从Tn(F)到自身的所有保矩阵群逆的线性双射被刻划.  相似文献   
992.
张廷蓉  吕百达 《激光技术》2003,27(2):147-149
基于矩阵合成和分解理论,提出了可将三维像散厄米高斯光束变换为对称拉盖尔高斯光束的两种新型光学系统,并以数值计算例加以说明。  相似文献   
993.
研究了求解无约束极值问题的DFP变尺度法和FR共轭梯度法的关系问题.证明了在应用于求解二次函数的极值问题时,若将初始尺度矩阵取为单位矩阵,二者实际上是等价的,即两种方法求出的极小化点列是相同的.  相似文献   
994.
Conventional electrorheological (ER) fluids consist of electrically polarizable particles dispersed in an inert insulating liquid. They are characterized by a development of a yield stress upon application of an external electric field. They resemble Bingham fluids with yield stress value depending on electric field. A viscosity increase in the presence of an electric field has been also found in homogeneous solutions of liquid crystalline polymers with no yield stress observed. In this study these two types of fluids and combined dispersions of the solid particles in the liquid crystalline matrix were investigated. A lyotropic liquid crystalline polymer—poly(n‐hexyl isocyanate) (PHIC)—dissolved in xylene was chosen as the active matrix. The dispersed solid phase was comprised of two kinds of polymers: pyrolyzed polyacrylonitryle (PAN) showing electron conductivity, and PAN doped with two salts (KSCN, NaSCN), resulting in ionic conductivity. The rheological measurements under an electric field were performed. The pristine xylene solution of PHIC was characterized first as well as the 15% m/m dispersions of PAN powders in silicone oil. Then the dispersions in the liquid crystalline matrix were investigated showing a strong ER effect whose magnitude was considerably enhanced in comparison to both ER active components measured separately. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
995.
动态矩阵控制是一种应用广泛的预测控制算法.因其建模简便、易于在线实施.在工业控制中得到了越来越广泛的应用.水轮机调节系统是一个非线性、参数时变的非最小相位系统.传统的控制手段不能达到满意的控制效果,本文将动态矩阵控制算法应用于水轮机调节系统中,仿真结果表明.对于混流式水轮机组转速得到快速而稳定的控制.  相似文献   
996.
有源腔模式的有限元数值矩阵计算法   总被引:4,自引:0,他引:4  
提出了一种计算有源腔模式分布的有限元数值矩阵方法。对腔镜进行基于菲涅耳–基尔霍夫衍射积分定理的有限元划分,利用MATLAB计算出光一次往返的传输矩阵。然后根据自再现理论,求出矩阵的特征值和特征向量。从而确定谐振腔的模式分布,给新型谐振腔的研究带来极大方便。  相似文献   
997.
The theorem proved in this paper gives a congruence for the traces of powers of an algebraic integer for the case in which the exponent of the power is a prime power. The theorem implies a congruence in Gauss’ form for the traces of the sums of powers of algebraic integers, generalizing many familiar versions of Fermat’s little theorem. Applied to the traces of integer matrices, this gives a proof of Arnold’s conjecture about the congruence of the traces of powers of such matrices for the case in which the exponent of the power is a prime power.  相似文献   
998.
The ability to achieve high-yield focal plane arrays from Hg1−xCdxTe molecular beam epitaxy material depends strongly on postgrowth wafer analysis. Nondestructive analysis that can determine layer thicknesses as well as alloy compositions is critical in providing run-to-run consistency. In this paper, we incorporate the use of a thin film transmission matrix model to analyze Fourier transform infrared (FTIR) transmission spectra. Our model uses a genetic algorithm along with a multidimensional, nonlinear minimization Nelder-Mead algorithm to determine the composition and thickness of each layer in the measured epitaxial structure. Once a solution has been found, the software is able to predict detector performance such as quantum efficiency and spectral response. We have verified our model by comparing detector spectral data to our predicted spectral data derived from the room-temperature FTIR transmission data. Furthermore, the model can be used to generate design curves for detectors with varying absorber thicknesses and/or different operating temperatures. The consequence of this are reduced cycle times and reduced design variations.  相似文献   
999.
We study rule induction from two decision tables as a basis of rough set analysis of more than one decision tables. We regard the rule induction process as enumerating minimal conditions satisfied with positive examples but unsatisfied with negative examples and/or with negative decision rules. From this point of view, we show that seven kinds of rule induction are conceivable for a single decision table. We point out that the set of all decision rules from two decision tables can be split in two levels: a first level decision rule is positively supported by a decision table and does not have any conflict with the other decision table and a second level decision rule is positively supported by both decision tables. To each level, we propose rule induction methods based on decision matrices. Through the discussions, we demonstrate that many kinds of rule induction are conceivable.  相似文献   
1000.
运动单站测角、角变化率无源定位中,观测方程和状态方程建立在不同坐标系中。本文引入一个坐标转换矩阵把状态向量在两个坐标系中的坐标联系起来,推导了坐标转换矩阵,计算出由平台姿态误差带来的坐标转换矩阵误差,并应用到跟踪滤波方程中,最后给出计算机仿真结果。  相似文献   
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