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111.
Here we prove that every compact differential manifold has a smooth algebraic model defined over Q. In dimension 2 we find an algebraic model (may be singular) defined over Q and birational over Q to the projective plane. 相似文献
112.
Scott McCullough 《Integral Equations and Operator Theory》1992,15(1):43-71
Kernels over the unit disk for which a version of Carathéodory interpolation is true are characterized in a simple computationally verifiable manner. 相似文献
113.
Hideaki Ishikawa 《Archiv der Mathematik》2002,79(6):439-448
In this paper we introduce a certain sum by using Dirichlet characters. We investigate the Riesz mean of the sum using the
analytic properties of the MultipleL-function systematically.
Eine überarbeitete Fassung ging am 6. 8. 2001 ein 相似文献
114.
Summary. In this paper we are interested in two phase flow problems in porous media. We use a Dual Mesh Method to discretize this
problem with finite volume schemes. In a simplified case (elliptic - hyperbolic system) we prove the convergence of approximate
solutions to the exact solutions. We use the Dual Mesh Method in physically complex problems (heterogeneous cases with non
constant total mobility). We validate numerically the Dual Mesh Method on practical examples by computing error estimates
for different test-cases.
Received March 21, 1997 / Revised version received October 13, 1997 相似文献
115.
We consider the Abelian gauge theory related to the interaction between the solitary waves of the nonlinear Klein-Gordon equation
and the electromagnetic field. We analyze the existence of electromagnetostatic solutions and, in particular, of vortices.
Dedicated to the memory of Professor Aldo Cossu 相似文献
116.
Greg Gillen Albert Fahey Matt Wagner Christine Mahoney 《Applied Surface Science》2006,252(19):6537-6541
Thin monolayer and bilayer films of spin cast poly(methyl methacrylate) (PMMA), poly(2-hydroxyethyl methacrylate) (PHEMA), poly(lactic) acid (PLA) and PLA doped with several pharmaceuticals have been analyzed by dynamic SIMS using SF5+ polyatomic primary ion bombardment. Each of these systems exhibited minimal primary beam-induced degradation under cluster ion bombardment allowing molecular depth profiles to be obtained through the film. By combing secondary ion imaging with depth profiling, three-dimensional molecular image depth profiles have been obtained from these systems. In another approach, bevel cross-sections are cut in the samples with the SF5+ primary ion beam to produce a laterally magnified cross-section of the sample that does not contain the beam-induced damage that would be induced by conventional focussed ion beam (FIB) cross-sectioning. The bevel surface can then be examined using cluster SIMS imaging or other appropriate microanalysis technique. 相似文献
117.
在原子、分子和纳米材料中的高次谐波为非线性光学开辟了一个崭新的研究领域.其响应时间之短、能量之高,引起了人们的高度重视.目前的研究达到了白热化的程度.还有很多问题没有解决.文章首先简要地介绍了这一个新的领域.然后用一个简单的例子引出有名的辐射截断方程,最后用C60作为一个例子说明如何详细地计算辐射能量谱. 相似文献
118.
We give a small functorial algebraic model for the 2-stage Postnikov section of the K-theory spectrum of a Waldhausen category and use our presentation to describe the multiplicative structure with respect to biexact functors. 相似文献
119.
Ronald Ortner 《Operations Research Letters》2007,35(5):619-626
In ergodic MDPs we consider stationary distributions of policies that coincide in all but n states, in which one of two possible actions is chosen. We give conditions and formulas for linear dependence of the stationary distributions of n+2 such policies, and show some results about combinations and mixtures of policies. 相似文献
120.
In this paper we study random orderings of the integers with a certain invariance property. We describe all such orders in a simple way. We define and represent random shuffles of a countable set of labels and then give an interpretation of these orders in terms of a class of generalized riffle shuffles. 相似文献