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31.
A computer code is described for the calculation of light-scattering properties of randomly oriented, axially symmetric coated particles, in the framework of the T-matrix theory. The underlying mathematical background is outlined briefly and convergence procedures are discussed. After outlining the input-output interaction between user and code, benchmark results are presented for two distinct shapes: coated, centered spheroids and offset coated spheres.  相似文献   
32.
Let X be a Banach space and let fL(R+;X) whose Laplace transform extends analytically to some region containing iR?{0}, possibly having a pole at the origin. In this paper, we give estimates of the decay of certain slight suitable modification of f in terms of the growth of its Laplace transform along the imaginary axis. This technique is applied to obtain decay estimates of smooth orbits of bounded C0-semigroups whose infinitesimal generators have an arbitrary finite boundary spectrum. These results are close to those given recently by C.J.K. Batty and T. Duyckaerts.  相似文献   
33.
In this paper, we address the problem of observer design for a class of Lipschitz nonlinear discrete-time systems with time-delay. The main contribution lies in the use of a new structure of the proposed observer with a novel Lyapunov-Krasovskii functional. Thanks to these designs, new nonrestrictive synthesis conditions, expressed in terms of linear matrix inequalities (LMIs), are obtained. Indeed, the obtained LMIs contain more degree of freedom than those established by the approaches available in the literature which consider a simple Luenberger observer with a simple Lyapunov function for the stability analysis. An extension of the presented result to H performance analysis is given in order to take into account the noise (if it exists) affecting the considered system.  相似文献   
34.
Our Fortran codes for hard sphere fluids and their mixtures for the correlation functions that arise from the Percus–Yevick theory and the Verlet–Weis semi-empirical correction have proven useful during a period of nearly four decades and continue to be useful. In order to make these codes even more widely available, a brief summary is presented here and listings of these codes are given in the electronically accessible Supplementary Material to this paper.  相似文献   
35.
In a commutative Banach algebraB the set of logarithmic residues (i.e., the elements that can be written as a contour integral of the logarithmic derivative of an analyticB-valued function), the set of generalized idempotents (i.e., the elements that are annihilated by a polynomial with non-negative integer simple zeros), and the set of sums of idempotents are all the same. Also, these (coinciding) sets consist of isolated points only and are closed under the operations of addition and multiplication. Counterexamples show that the commutativity condition onB is essential. The results extend to logarithmic residues of meromorphicB-valued functions.  相似文献   
36.
热等静压扩散连接反应层元素互扩散的动力学模拟计算   总被引:2,自引:0,他引:2  
通过DICTRA-THERMO-CALC动力学和热力学联合计算软件对DD402单晶和Rene95粉末高温合金进行热等静压扩散连接反应层元素互扩散规律的模拟计算,计算结果表明,此种模拟计算方法可以较好地反应扩散偶中元素的互扩散规律,与实验结果基本吻合,在此基础上,分析了计算了温度和时间对扩散连接过程中Al元素互扩散规律的影响,最终得出此种模拟计算方法可以为热等静压扩散连接工艺的制定和优化提供较好的理论依据。  相似文献   
37.
38.
We classify the connected commutative algebraic groups having as lattice of connected closed subgroups a projective space and determine the coordinate fields of these projective spaces. Furthermore we determine the not necessarily commutative connected algebraic groups with a distributive or boolean lattice of connected closed subgroups.
Received: 3 December 2004  相似文献   
39.
谢秀兰  曹荣 《结构化学》1994,13(6):480-488
对~(95)MoNMR的特点、提供的信息、发展历史以及研究现状作了较为全面的介绍。结合本实验室研究工作和部分文献报道对其在钼化学研究中的应用进行了较为详细的论述,同时还指出影响~(95)MoNMR的因素并进行了简单分类和讨论。  相似文献   
40.
In this paper we characterize the existence and uniqueness of periodic solutions of inhomogeneous abstract delay equations and establish maximal regularity results for strong solutions. The conditions are obtained in terms of R-boundedness of linear operators determined by the equations and Lp- Fourier multipliers. Periodic mild solutions are also studied and characterized.  相似文献   
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