作者：
Chang, SSYibin Univ
Dept Math Yibin 644007 Sichuan Peoples R China Sichuan Univ
Dept Math Chengdu 610064 Sichuan Peoples R China
The purpose of this paper is to introduce the concept of general fuzzy quasi variational inclusions and to study the existence problem and iterative approximation problem of solutions for some kinds of fuzzy quasivari...
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The purpose of this paper is to introduce the concept of general fuzzy quasi variational inclusions and to study the existence problem and iterative approximation problem of solutions for some kinds of fuzzy quasivariational inclusions in Banach spaces. By using the resolvent operator technique, Nadler's fixed point theorem and new analytic technique, some existence theorems of solutions and iterative approximation for solving this kind of fuzzy quasivariational inclusions are established. The results presented in this paper are new, which generalize, improve and unify a number of recent results. (C) 2003 Elsevier Inc. All rights reserved.
This paper treats the multidimensional application of a previous iterative Monte Carlo algorithm that enables the computation of approximations in L(2). The case of regular functions is studied using a Fourier basis o...
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This paper treats the multidimensional application of a previous iterative Monte Carlo algorithm that enables the computation of approximations in L(2). The case of regular functions is studied using a Fourier basis on periodised functions, Legendre and Tchebychef polynomial bases. The dimensional effect is reduced by computing these approximations on Korobov-like spaces. Numerical results show the efficiency of the algorithm for both approximation and numerical integration. (C) 2003 Elsevier B.V. All rights reserved.
This work presents an efficient monotonic algorithm for the numerical solution of the obstacle problem and the Signorini problems, when they are discretized either by the finite element method or by the finite volume ...
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This work presents an efficient monotonic algorithm for the numerical solution of the obstacle problem and the Signorini problems, when they are discretized either by the finite element method or by the finite volume method. The convergence of this algorithm applied to the discrete problem is proven in both cases.
In a Bayesian tomographic maximum a posteriori (MAP) reconstruction, an estimate of the object f is computed by iteratively minimizing an objective function that typically comprises the sum of a log-likelihood (data c...
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In a Bayesian tomographic maximum a posteriori (MAP) reconstruction, an estimate of the object f is computed by iteratively minimizing an objective function that typically comprises the sum of a log-likelihood (data consistency) term and prior (or penalty) term. The prior can be used to stabilize the solution and to also impose spatial properties on the solution. One such property, preservation of edges and locally monotonic regions, is captured by the well-known median root prior (MRP) [1], [2], an empirical method that has been applied to emission and transmission tomography. We propose an entirely new class of convex priors that depends on f and also on m, an auxiliary field in register with f. We specialize this class to our median prior (MP). The approximate action of the median prior is to draw, at each iteration, an object voxel toward its own local median. This action is similar to that of MRP and results in solutions that impose the same sorts of object properties as does MRP. Our MAP method is not empirical, since the problem is stated completely as the minimization of a joint (on f and m) objective. We propose an alternating algorithm to compute the joint MAP solution and apply this to emission tomography, showing that the reconstructions are qualitatively similar to those obtained using MRP.
In this paper, we show that iterative power control by measuring intercell interference can converge faster than by measuring total receiver power. This interesting result is obtained by means of reducing the dimensio...
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In this paper, we show that iterative power control by measuring intercell interference can converge faster than by measuring total receiver power. This interesting result is obtained by means of reducing the dimension of quality of service (QoS) constraint equations from the number of mobile stations (MSs) to the number of base stations (BSs) in the system. By observing the intercell interference and total received power, respectively, we first derive the microscopic descriptions, namely, the QoS constraint equations expressed in terms of number of MSs. Then the microscopic descriptions are transformed as macroscopic descriptions, which are the QoS constraint equations expressed in terms of number of BSs. Theoretic and simulation results show that the pair of description matrices for microscopic and macroscopic descriptions share the same spectral radius, which is the convergence rate or contracting rate indicator of related power-control iterations. Comparison of the macroscopic description matrices based on total received power and intercell interference shows that the former has the larger spectral radius, which justified the main conclusion-of this paper. We also show that the convergence rate indicator decreases with the increase of number of MSs and their QoS requirements, typically the required E-b/N-o. The asynchronous algorithms are also investigated and are proved to have faster convergence speed than the synchronous ones. Numerical simulations are conducted to verify the theoretic, results and to examine the performances of the proposed algorithms.
The dynamic flexibility method presented can be used to extract constrained structural modes from free test data. Under certain conditions the original dynamic flexibility method is not effective: 1) when the constrai...
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The dynamic flexibility method presented can be used to extract constrained structural modes from free test data. Under certain conditions the original dynamic flexibility method is not effective: 1) when the constrained structural test frequency moves into higher-order free-free analytical frequency range and 2) when the test frequency moves closer to any value lambda(h,s) of interesting in the higher-order analytical frequencies of the free structure. The former is the test frequency range of a constrained structure larger than that of a free structure. The largest test frequency omega(max) of a constrained structure is higher than the smallest frequency lambda(h,k + 1) in the higher-order analytical frequencies of a free structure. Under these two separate situations a power series used in the original dynamic flexibility method is diverging, which leads to an invalid method. To solve these problems properly, an improvement of the dynamic flexibility method is proposed. The kernel technique of this improvement is a "hybrid shifting frequency" procedure. From the numerical results it is found that the improved method is better than the old method for all conditions.
Consider the model Y = betaX + is an element of with interval-censored data, where E has an unknown c.d.f. F-0 The semi-parametric MLE (SMLE) of beta is well defined, but cannot be obtained by algorithms for M-estimat...
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Consider the model Y = betaX + is an element of with interval-censored data, where E has an unknown c.d.f. F-0 The semi-parametric MLE (SMLE) of beta is well defined, but cannot be obtained by algorithms for M-estimators, or by the Newton-Raphson method or the Monte-Carlo method. Thus it has not been studied in the literature even in the case of complete data. We propose a feasible algorithm to obtain all solutions of the SMLE. Simulation suggests that the SMLE is consistent and the bootstrap estimator of the variance of the SMLE matches the sample variance. We compare the SMLE to the Buckley-James estimator (BJE) in four data sets with sample sizes up to 374. The results show-that the SMLE is more robust and more reliable than the BJE.
There are several methods in linear dynamic substructuring for numerical simulation of complex structures in the low-frequency range, that is, in the modal range. For instance, the Craig-Bampton method is a very effic...
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There are several methods in linear dynamic substructuring for numerical simulation of complex structures in the low-frequency range, that is, in the modal range. For instance, the Craig-Bampton method is a very efficient and popular method. Such a method, based on the use of the first normal structural modes of each undamped substructure with fixed coupling interface, leads to small-sized reduced matrix models. In the medium-frequency range, that is, in the nonmodal range, and for complex structures, a large number of normal structural modes should be computed with finite element models having a very large number of degrees of freedom. Such an approach is not really efficient and, generally, cannot be carried out. We present a new approach in dynamic substructuring for numerical calculation of complex structures in the medium-frequency range. This approach is still based on the use of the Craig-Bampton decomposition of the admissible displacement field, but the reduced matrix model of each substructure with fixed coupling interface is not constructed using the normal structural modes of each undamped substructure but instead using the eigenfunctions associated with the first highest eigenvalues of the mechanical energy operator relative to the medium-frequency band for each damped substructure with fixed coupling interface. The method and numerical example are presented.
In this paper, we introduce a new class of monotone operators-H-monotone operators. The resolvent operator associated with an H-monotone operator is defined and its Lipschitz continuity is presented. We also introduce...
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In this paper, we introduce a new class of monotone operators-H-monotone operators. The resolvent operator associated with an H-monotone operator is defined and its Lipschitz continuity is presented. We also introduce and study a new class of variational inclusions involving H-monotone operators and construct a new algorithm for solving this class of variational inclusions by using the resolvent operator technique. (C) 2003 Elsevier Inc. All rights reserved.
The integrity assessment of defective pipelines represents a practically important task of structural analysis and design in various technological areas,such as oil and gas indus- try,power plant engineering and chemi...
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The integrity assessment of defective pipelines represents a practically important task of structural analysis and design in various technological areas,such as oil and gas indus- try,power plant engineering and chemical *** iterative algorithm is presented for the kinematic limit analysis of 3-D rigid-perfectly plastic bodies.A numerical path scheme for radial loading is adopted to deal with complex multi-loading *** numerical procedure has been applied to carry out the plastic collapse analysis of pipelines with part-through slot under internal pressure,bending moment and axial *** effects of various shapes and sizes of part-through slots on the collapse loads of pipelines are systematically investigated and *** typical failure modes corresponding to different configurations of slots and loading forms are studied.
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