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101.
Nadjib Bouzar 《Annals of the Institute of Statistical Mathematics》2004,56(3):497-510
The purpose of this paper is to introduce and study the concepts of discrete semi-stability and geometric semi-stability for
distributions with support inZ
+. We offer several properties, including characterizations, of discrete semi-stable distributions. We establish that these
distributions posses the property of infinite divisibility and that their probability generating functions admit canonical
representations that are analogous to those of their continuous counterparts. Properties of discrete geometric semi-stable
distributions are deduced from the results obtained for discrete semi-stability. Several limit theorems are established and
some examples are constructed. 相似文献
102.
103.
In this paper, a fully discrete format of nonlinear Galerkin mixed element method with two-step discretization of time for the non stationary conduction-convection problems is presented. The existence and the convergence of the fully discrete mixed element solution are shown. On the basis of [9] and [10], we have proved that the schemes have second-order convergence accuracy for the time discretization. 相似文献
104.
Teresa Regińska 《BIT Numerical Mathematics》2004,44(1):119-133
The paper concerns conditioning aspects of finite-dimensional problems arising when the Tikhonov regularization is applied
to discrete ill-posed problems. A relation between the regularization parameter and the sensitivity of the regularized solution
is investigated. The main conclusion is that the condition number can be decreased only to the square root of that for the
nonregularized problem. The convergence of solutions of regularized discrete problems to the exact generalized solution is
analyzed just in the case when the regularization corresponds to the minimal condition number. The convergence theorem is
proved under the assumption of the suitable relation between the discretization level and the data error. As an example the
method of truncated singular value decomposition with regularization is considered.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
105.
Svante?JansonEmail author Jean-Fran?ois?Marckert 《Journal of Theoretical Probability》2005,18(3):615-645
The discrete snake is an arborescent structure built with the help of a conditioned Galton-Watson tree and random i.i.d. increments Y. In this paper, we show that if
and
, then the discrete snake converges weakly to the Brownian snake (this result was known under the hypothesis
). Moreover, if this condition fails, and the tails of Y are sufficiently regular, we show that the discrete snake converges weakly to an object that we name jumping snake. In both case, the limit of the occupation measure is shown to be the integrated super-Brownian excursion. The proofs rely on the convergence of the codings of discrete snake with the help of two processes, called tours. 相似文献
106.
介绍了采用微机数模转换器接口技术实现对小直流电机转速控制的实验方案,并对实验结果进行了讨论. 相似文献
107.
Adrian Vasiu 《Central European Journal of Mathematics》2005,3(1):14-25
We include short and elementary proofs of two theorems that characterize reductive group schemes over a discrete valuation
ring, in a slightly more general context. 相似文献
108.
Elva Ortega-Torres Marko Rojas-Medar 《Numerical Functional Analysis & Optimization》2013,34(5-6):612-637
We present an optimal error estimate of the numerical velocity, pressure, and angular velocity for the fully discrete penalty finite element method of the micropolar equations when the parameters ?, Δ t, and h are sufficiently small. In order to obtain this estimate, we present the time discretization of the penalty micropolar equation that is based on the backward Euler scheme; the spatial discretization of the time discretized penalty micropolar equation is based on a finite elements space pair (X h , M h ) that satisfies some approximations properties. 相似文献
109.
Yanping Chen Lingli Liu Zuliang Lu 《Numerical Functional Analysis & Optimization》2013,34(10):1135-1157
In this article, we shall give a brief review on the fully discrete mixed finite element method for general optimal control problems governed by parabolic equations. The state and the co-state are approximated by the lowest order Raviart–Thomas mixed finite element spaces and the control is approximated by piecewise constant elements. Furthermore, we derive a posteriori error estimates for the finite element approximation solutions of optimal control problems. Some numerical examples are given to demonstrate our theoretical results. 相似文献
110.
Vasiliy Ye. Belozyorov 《Applied mathematics and computation》2011,218(8):4546-4566
The wide class of 3-D autonomous systems of quadratic differential equations, in each of which either there is a couple of coexisting limit cycles or there is a couple of coexisting chaotic attractors, is found. In the second case the couple consists of either Lorentz-type attractor and another attractor of a new type or two Lorentz-type attractors. It is shown that the chaotic behavior of any system of the indicated class can be described by the Ricker discrete population model: zi+1 = zi exp(r − zi), r > 0, zi > 0, i = 0, 1, … . The values of parameters, at which in the 3-D system appears either the couple of limit cycles or the couple of chaotic attractors, or only one limit cycle, or only one sphere-shaped chaotic attractor, are indicated. Examples are given. 相似文献