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71.
Summary We prove an invariance principle in probability for planar point processes associated with extremal processes. The underlying sequence of random variables is absolutely regular, and satisfies a local asymptotic independence condition. A strong approximation for triangular arrays of such point processes is also stated. We apply these results to the weak convergence of intermediate quantile functions. 相似文献
72.
We determine all complete intersection surface germs whose Pythagoras number is 2, and find that they are all embedded in 3 and have the property that every positive semidefinite analytic function germ is a sum of squares of analytic function germs. In addition, we discuss completely these properties for mixed surface germs in 3. Finally, we find in higher embedding dimension three different families with these same properties. Partially supported by DGICYT, BFM2002-04797 and HPRN-CT-2001-00271
Mathematical Subject Classification (2000): 11E25, 14P15.An erratum to this article can be found at 相似文献
73.
Abstract. We propose a general approach to deal with nonlinear, nonconvex variational problems based on a reformulation of the problem
resulting in an optimization problem with linear cost functional and convex constraints. As a first step we explicitly explore
these ideas to some one-dimensional variational problems and obtain specific conclusions of an analytical and numerical nature. 相似文献
74.
Parallel Newton two-stage iterative methods to solve nonlinear systems are studied. These algorithms are based on both the multisplitting technique and the two-stage iterative methods. Convergence properties of these methods are studied when the Jacobian matrix is either monotone or an H-matrix. Furthermore, in order to illustrate the performance of the algorithms studied, computational results about these methods on a distributed memory multiprocessor are discussed.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
75.
José Trashorras 《Comptes Rendus Mathematique》2003,336(1):69-74
We improve the Large Deviations Principle satisfied by a Coarse Grained process already analyzed by Boucher, Ellis and Turkington [Ann. Probab. 27 (1999) 297–324]. To cite this article: J. Trashorras, C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
76.
An important component of any initial-value solver for higher-index differential–algebraic equations consists in the computation of consistent initial values. In a recent paper [5], an algorithm is proposed which is applicable to a very general class of index-2 systems. Unfortunately, the computational expense is rather high. We present a modification of this approach, which gives rise to a MATLAB implementation capable of handling systems of moderate dimension (several thousands of unknowns). The algorithm is illustrated by examples. 相似文献
77.
In this paper we present an inertia result for Stein equations with
an indefinite right hand side. This result is applied to establish connnections
between the inertia of invertible hermitian block Toeplitz matrices and associated
orthogonal polynomials. 相似文献
78.
The first author was supported in part by CNPq 相似文献
79.
Kortunov P Vasenkov S Kärger J Fé Elía M Perez M Stöcker M Papadopoulos GK Theodorou D Drescher B McElhiney G Bernauer B Krystl V Kocirik M Zikanova A Jirglova H Berger C Gläser R Weitkamp J Hansen EW 《Magnetic resonance imaging》2005,23(2):233-237
Pulsed-field gradient nuclear magnetic resonance (PFG NMR) has been applied to study molecular diffusion in industrial fluid catalytic cracking (FCC) catalysts and in USY zeolite for a broad range of molecular displacements and temperatures. The results of this study have been used to elucidate the relevance of molecular transport on various displacements for the rate of molecular exchange between catalyst particles and their surroundings. It turned out that this rate, which may determine the overall rate and selectivity of FCC process, is primarily related to the diffusion mode associated with displacements larger than the size of zeolite crystals located in the particles but smaller than the size of the particles. This conclusion has been confirmed by comparative studies of the catalytic performance of different FCC catalysts. 相似文献
80.
Mechanically driven alloying of immiscible elements 总被引:1,自引:0,他引:1