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131.
Jiaquan Xie Zhongkai Ren Yugui Li Xiaogang Wang Tao Wang 《Numerical Methods for Partial Differential Equations》2019,35(5):1890-1903
In the current study, an approximate scheme is established for solving the fractional partial differential equations (FPDEs) with Volterra integral terms via two‐dimensional block‐pulse functions (2D‐BPFs). According to the definitions and properties of 2D‐BPFs, the original problem is transformed into a system of linear algebra equations. By dispersing the unknown variables for these algebraic equations, the numerical solutions can be obtained. Besides, the proof of the convergence of this system is given. Finally, several numerical experiments are presented to test the feasibility and effectiveness of the proposed method. 相似文献
132.
Caiyun Jin 《Numerical Functional Analysis & Optimization》2019,40(7):825-843
In this article, an approximate minimax theorem for bi-lower-semicontinuous set-valued mapping was proved, relationships between semicontinuous set-valued mappings are discussed and the existence of approximate maxmin was given. The minimax theorem in this article is the first minimax theorem that doesn’t require the set-valued mappings to be continuous. 相似文献
133.
何家莉 《纯粹数学与应用数学》2019,35(2):229-234
利用一般映射研究了覆盖近似空间的一些性质,并证明了一些结论.接着定义了覆盖空间的粗糙连续映射及粗糙同胚映射.最后在覆盖粗糙连续映射和覆盖粗糙同胚映射的条件下,研究了两个覆盖近似空间的有关性质,进而在某种程度上为覆盖近似空间的分类提供了理论依据. 相似文献
134.
《Operations Research Letters》2021,49(2):157-163
The method of cyclic projections finds nearest points in the intersection of finitely many affine subspaces. To accelerate convergence, Gearhart & Koshy proposed a modification which, in each iteration, performs an exact line search based on minimising the distance to the solution. When the subspaces are linear, the procedure can be made explicit using feasibility of the zero vector. This work studies an alternative approach which does not rely on this fact, thus providing an efficient implementation in the affine setting. 相似文献
135.
研究了带约束条件集值优化问题近似Henig有效解集的连通性.在实局部凸Hausdorff空间中,讨论了可行域为弧连通紧的,目标函数为C-弧连通的条件下,带约束条件集值优化问题近似Henig有效解集的存在性和连通性.并给出了带约束条件集值优化问题近似Henig有效解集的连通性定理. 相似文献
136.
Meiyan Fu & Tiao Lu 《高等学校计算数学学报(英文版)》2021,14(4):1110-1135
A general one-fluid cavitation model is proposed for a family of Mie-Grüneisen equations of state (EOS), which can provide a wide application of cavitation flows, such as liquid-vapour transformation and underwater explosion. An
approximate Riemann problem and its approximate solver for the general cavitation
model are developed. The approximate solver, which provides the interface pressure
and normal velocity by an iterative method, is applied in computing the numerical
flux at the phase interface for our compressible multi-medium flow simulation on
Eulerian grids. Several numerical examples, including Riemann problems and underwater explosion applications, are presented to validate the cavitation model and
the corresponding approximate solver. 相似文献
137.
138.
P.A. HaworthS.C. Power 《Journal of Functional Analysis》2002,195(2):207-229
Necessary and sufficient conditions are obtained for the uniqueness of standard regular AF maximal abelian self-adjoint algebras in regular limit algebras up to approximate inner unitary equivalence. 相似文献
139.
P. L. Ivankov 《Mathematical Notes》2005,77(3-4):476-481
In this paper, estimates for nonhomogeneous linear forms in values of hypergeometric functions with irrational parameters are refined. This refinement is carried out by means of an optimal choice of the degree of the zeroth polynomial appearing in the construction of approximate functional forms.Translated from Matematicheskie Zametki, vol. 77, no. 4, 2005, pp. 515–521.Original Russian Text Copyright © 2005 by P. L. Ivankov.This revised version was published online in April 2005 with a corrected issue number. 相似文献
140.
We consider the behavior of an (anti)instanton in the field of a pointlike source of a Euclidean non-Abelian field and investigate
(anti)instanton deformations described by variations of its characteristic parameters. We formulate the variational problem
of seeking the corresponding “crumpled” topological configurations and solve it algebraically using the Ritz method (of multipole
decomposition of deformation fields). We investigate the domain of parameters specific for the instanton liquid model. We
propose a simple method of taking contributions of such configurations in the functional integral into account approximately.
In the framework of superposition analysis, we obtain an estimate for the mean energy of the source in the instanton liquid,
and the estimate increases linearly with distance. In the case of a dipole in the color-singlet state, the energy is a linear
function of the distance between the sources with the “strength” coefficient agreeing well with the known model and lattice
estimates.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 146, No. 2, pp. 267–298, February, 2006. 相似文献