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41.
Somyot Plubtieng Rattanaporn Punpaeng 《Journal of Mathematical Analysis and Applications》2007,336(1):455-469
In this paper, we introduce two iterative schemes by the general iterative method for finding a common element of the set of an equilibrium problem and the set of fixed points of a nonexpansive mapping in a Hilbert space. Then, we prove two strong convergence theorems for nonexpansive mappings to solve a unique solution of the variational inequality which is the optimality condition for the minimization problem. These results extended and improved the corresponding results of Marino and Xu [G. Marino, H.K. Xu, A general iterative method for nonexpansive mapping in Hilbert spaces, J. Math. Anal. Appl. 318 (2006) 43-52], S. Takahashi and W. Takahashi [S. Takahashi, W. Takahashi, Viscosity approximation methods for equilibrium problems and fixed point problems in Hilbert spaces, J. Math. Anal. Appl. 331 (1) (2007) 506-515], and many others. 相似文献
42.
Jonathan M. Borwein 《Optimization Letters》2007,1(1):21-32
This paper is a companion to a lecture given at the Prague Spring School in Analysis in April 2006. It highlights four distinct variational methods of proving that a finite dimensional Chebyshev set is convex and hopes to inspire renewed work on the open question of whether every Chebyshev set in Hilbert space is convex. 相似文献
43.
Zhiyue Zhang Dingwen Deng 《Numerical Methods for Partial Differential Equations》2007,23(6):1530-1559
A modified backward difference time discretization is presented for Galerkin approximations for nonlinear hyperbolic equation in two space variables. This procedure uses a local approximation of the coefficients based on patches of finite elements with these procedures, a multidimensional problem can be solved as a series of one‐dimensional problems. Optimal order H01 and L2 error estimates are derived. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007 相似文献
44.
In this paper,we consider a class of quadratic maximization problems.For a subclass of the problems,we show that the SDP relaxation approach yields an approximation solution with the ratio is dependent on the data of the problem with α being a uniform lower bound.In light of this new bound,we show that the actual worst-case performance ratio of the SDP relaxation approach (with the triangle inequalities added) is at least α δd if every weight is strictly positive,where δd > 0 is a constant depending on the problem dimension and data. 相似文献
45.
Ekatherina A. Karatsuba 《Numerical Algorithms》2007,45(1-4):127-137
A new approach to the study of the Jaynes–Cummings sum, which determines the atomic inversion in quantum model of a single
two-level atom interacting with a single mode of the quantized radiation field, based on the number theory theorems on approximation
of trigonometric sums is presented.
相似文献
46.
由“从正则分布出发,在小涨落近似下得出的能量涨落分布公式”求得的能量涨落的二次矩与直接由正则分布求得的二次矩完全相同,但分别由二求得的高次矩并不完全相同。 相似文献
47.
M. Iuga G. Steinle-Neumann J. Meinhardt 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(2):127-133
Athermal elasticity for some ceramic materials (α-Al2O3,
SiC (α and β phases), TiO2 (rutile and anatase),
hexagonal AlN and TiB2, cubic BN and CaF2, and monoclinic
ZrO2) have been investigated via density functional theory.
Energy-volume equation-of-state computations to obtain the zero pressure
equilibrium volume and bulk modulus as well as computations of the full
elastic constant tensor of these ceramics at the experimental zero pressure
volume have been performed. The present results for the single crystal
elasticity are in good agreement with experiments both for the aggregate
properties (bulk and shear modulus) and the elastic anisotropy. In contrast,
a considerable discrepancy for the zero pressure bulk modulus of some
ceramics evaluated from the energy-volume fit to the computational zero
pressure volume has been observed. 相似文献
48.
Deguang Han 《应用数学学报(英文版)》1994,10(2):213-219
In this paper we will prove some theorems on theM-ideals of compact operators and the best approximation of quasitriangular operator algebras. These results improve and extend the known results in [4, 5, 7].This work is supported in part by the National Natural Science Foundation of China. 相似文献
49.
Heat transfer in lattice BGK modeled fluid 总被引:1,自引:0,他引:1
The thermal lattice BGK model is a recently suggested numerical tool aiming at solving problems of thermohydrodynamics. The quality of the lattice BGK simulation is checked in this paper by calculating temperature profiles in the Couette flow under different Eckert and Mach numbers. A revised lower order model is proposed to improve the accuracy and the higher order model is proved to be advantageous in this respect, especially in the flow regime with a higher Mach number. 相似文献
50.
Simple expressions are given for the mean delay, mean waiting time, and mean busy period length in a multiplexer. Data streams with active periods having a general distribution are permitted, and the data rate during the active periods can be random. Data can also arrive in batches. The key restrictions of the model are that the sources are independent, idle periods are exponentially distributed, and a source generates at least enough data during an active period to keep the server busy throughout the period. The exact formulas allow evaluation of the error in approximations such as a heavy traffic diffusion approximation.Both continuous and discrete time models are considered. The discrete-time model includes that studied by Viterbi and subsequently generalized by Neuts. The Pollaczek-Khinchine formula for the mean amount of work in anM/GI/1 queue is retrieved as a limiting case.Preliminary version presented at IEEE INFOCOM, San Francisco, April 1993. 相似文献