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141.
本文考虑一类带有无界单输入元的分布参数系统的无条件基扰动和极点配置问题,推广了文[1-4]的结果,同时亦解决了文[5]中提出的一个猜想. 相似文献
142.
Richard J. Pazur Robert E. Prud'homme 《Journal of Polymer Science.Polymer Physics》1994,32(8):1475-1484
The orientational states induced upon two-step biaxially stretching low-density polyethylene at 25°C have been investigated. A pole figure analysis of the (200), (020), and (002) crystalline planes has been employed to elucidate the evolution of the molecular crystalline orientation as a function of biaxial stretching. The initial uniaxial-like orientation induced along the extrusion direction of the films was gradually lost upon transverse stretching and, consequently, replaced by a biaxial orientation as suggested by the orientation functions. In these cases, the a crystallographic axis was observed to be strongly oriented along the film normal, thus confining the c and b axes to the film plane. The pole figures clearly indicate that the c and b axes are preferentially aligned 45° with respect to the stretching directions. This unique orientational state of the orthorhombic unit cell of polyethylene has been termed a biaxial-double orientation. Birefringence measurements on the biaxial samples indicated that the amorphous and crystalline regions are simultaneously biaxially oriented. The evolution of the crystalline orientation as a function of stretching was conveniently followed on a White/Spruiell orientation triangle. Quantification was hindered, however, by the presence of different crystal populations in the biaxially stretched samples. © 1994 John Wiley & Sons, Inc. 相似文献
143.
本文提出了一种高速低功耗、具有有源下拉电路和图腾柱式输出结构的CML(简称MCML)门电路;详细地阐述了MCML门电路的工作原理和优点;列出了电路仿真结果;并对其电路特性与ECL和APD-ECL电路进行了比较。 相似文献
144.
介绍了量子力学中散射振幅分波展开在复角动量平面中的解析延拓问题,讨论了Regge极点的物理意义及其应用. 相似文献
145.
146.
M. Phan L. G. Horta J. N. Juang R. W. Longman 《Journal of Optimization Theory and Applications》1993,79(1):59-86
This paper presents a formulation for identification of linear multivariable systems from single or multiple sets of input-output data. The system input-output relationship is expressed in terms of an observer, which is made asymptotically stable by an embedded eigenvalue assignment procedure. The prescribed eigenvalues for the observer may be real, complex, mixed real and complex, or zero corresponding to a deadbeat observer. In this formulation, the Markov parameters of the observer are first identified from input-output data. The Markov parameters of the actual system are then recovered from those of the observer and used to realize a state space model of the system. The basic mathematical formulation is derived, and numerical examples are presented to illustrate the proposed method. 相似文献
147.
148.
The positive extended KdV equation with self-consistent sources (eKdV+ ESCSs) is firstly presented and its related linear auxiliary equation is derived. The generalized binary Darboux transformation (DT) is applied to construct some new solutions of the eKdV+ ESCSs such as N-soliton solution, N-double pole solution and nonsingular N-positon solution. The properties of these solutions are analyzed. Moreover, the interaction of two solitons is discussed in detail. 相似文献
149.
150.
针对MATLAB控制系统工具箱中极点配置函数,不能完成状态反馈调节系统计算问题,提出借助符号数学工具箱中有关符号对象函数构成M文件,自动完成此过程。该方法计算结果与模拟结果比较,两者完全一致,证明此方法的正确性和实用性。 相似文献