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11.
CUI Xiao-bing ZHENG Shou-tian SUN Yan-qiong YANG Guo-yu ** . Coordination Hydrothermal Chemistry Group State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou P. R. China . State Key Laboratory of Coordination Chemistry Najing University Nanjing P. R. China 《高等学校化学研究》2004,(1)
IntroductionPolyoxometalatesarewidelystudiedfortheirin terestingapplicationsincatalysis ,electronicconduc tivity ,magnetism ,nonlinearopticsandmedicine[1— 4 ] .Whilethemechanismofthesynthesisofpolyoxometalatesremainselusiveandisoftende scribedasself assembly ,thereseemstobeanincreas inguseofthecombinationofthehydrothermalmethodandthestructure directingtemplate .There searchwiththismethodhasdemonstratedthatanum beroftransitionmetaloxides ,typicallyreducedmolybdenumoxides ,mixedvalancevanadiumo… 相似文献
12.
On General Mixed Quasivariational Inequalities 总被引:5,自引:0,他引:5
In this paper, we suggest and analyze several iterative methods for solving general mixed quasivariational inequalities by using the technique of updating the solution and the auxiliary principle. It is shown that the convergence of these methods requires either the pseudomonotonicity or the partially relaxed strong monotonicity of the operator. Proofs of convergence is very simple. Our new methods differ from the existing methods for solving various classes of variational inequalities and related optimization problems. Various special cases are also discussed. 相似文献
13.
G.N. Gatica 《Applied Mathematics Letters》1997,10(6):29-35
We study the solvability and Galerkin approximation of an exterior hyperelastic interface problem arising in plane elasticity. The weak formulation is obtained from an appropriate combination of a mixed finite element approach with a Dirichlet-to-Neumann method. The derivation of our results is based on some tools from nonlinear functional analysis and the Babuska-Brezzi theory for variational problems with constraints. 相似文献
14.
凸体的曲率映象与仿射表面积 总被引:4,自引:0,他引:4
本文研究了一些特殊凸体与其极体的曲率仿射表面积乘积的下界.对任意两个凸体,建立了它们的投影体的混合体积与其仿射表面积的一个不等式(见文[1-15]). 相似文献
15.
Mixed and hybrid finite element methods for the resolution of a wide range of linear and nonlinear boundary value problems (linear elasticity, Stokes problem, Navier–Stokes equations, Boussinesq equations, etc.) have known a great development in the last few years. These methods allow simultaneous computation of the original variable and its gradient, both of them being equally accurate. Moreover, they have local conservation properties (conservation of the mass and the momentum) as in the finite volume methods.The purpose of this paper is to give a review on some mixed finite elements developed recently for the resolution of Stokes and Navier–Stokes equations, and the linear elasticity problem. Further developments for a quasi-Newtonian flow obeying the power law are presented. 相似文献
16.
Csilla Bujtás 《Discrete Applied Mathematics》2007,155(11):1395-1407
For a mixed hypergraph H=(X,C,D), where C and D are set systems over the vertex set X, a coloring is a partition of X into ‘color classes’ such that every C∈C meets some class in more than one vertex, and every D∈D has a nonempty intersection with at least two classes. A vertex-orderx1,x2,…,xn on X (n=|X|) is uniquely colorable if the subhypergraph induced by {xj:1?j?i} has precisely one coloring, for each i (1?i?n). We prove that it is NP-complete to decide whether a mixed hypergraph admits a uniquely colorable vertex-order, even if the input is restricted to have just one coloring. On the other hand, via a characterization theorem it can be decided in linear time whether a given color-sequence belongs to a mixed hypergraph in which the uniquely colorable vertex-order is unique. 相似文献
17.
Hadi Mohammadi Bidhandi 《Annals of Operations Research》2006,143(1):237-250
This paper develops a mathematical model for project time compression problems in CPM/PERT type networks. It is noted this
formulation of the problem will be an adequate approximation for solving the time compression problem with any continuous
and non-increasing time-cost curve. The kind of this model is Mixed Integer Linear Program (MILP) with zero-one variables,
and the Benders' decomposition procedure for analyzing this model has been developed. Then this paper proposes a new approach
based on the surrogating method for solving these problems. In addition, the required computer programs have been prepared
by the author to execute the algorithm. An illustrative example solved by the new algorithm, and two methods are compared
by several numerical examples. Computational experience with these data shows the superiority of the new approach. 相似文献
18.
Zuo-liang Xu 《应用数学学报(英文版)》2007,23(4):629-636
In this paper,we study mixed elastico-plasticity problems in which part of the boundary is known,while the other part of the boundary is unknown and is a free boundary.Under certain conditions,this problemcan be transformed into a Riemann-Hilbert boundary value problem for analytic functions and a mixed boundaryvalue problem for complex equations.Using the theory of generalized analytic functions,the solvability of theproblem is discussed. 相似文献
19.
基于移动Agent技术的医学图像检索方法 总被引:1,自引:0,他引:1
针对现有医学图像检索方法中,检索算法速度较慢、准确性较低以及远程检索时占用大量带宽等问题,设计并实现了一种基于移动Agent技术的医学图像检索方法,重点讨论了该方法实现的关键技术,包括提升框架下的M带整数小波变换和提取多通道纹理特征的检索算法.模拟实验结果表明,该方法实时性较强,占用网络带宽较少,采用的算法运算速度提高近10倍、运算复杂度降低约50%,提取的纹理特征能充分表达图像内容,较好地满足了医学图像的检索要求,实现了对医学图像库快速较准确的检索. 相似文献
20.
Mixed integer programming (MIP) models are extensively usedto aid strategic and tactical decision making in many businesssectors. Solving MIP models is a computationally intensive processand there is a need to develop solution approaches that enablelarger models to be solved within acceptable timeframes. Inthis paper, we describe the implementation of a two-stage parallelbranch and bound (PB & B) algorithm for MIP. In stage 1of the algorithm, a multiple heuristic search is implementedin which a number of alternative search trees are investigatedusing a forest search in the hope of finding a good solutionquickly. In stage 2, the search is reorganized so that the branchesof a chosen tree are investigated in parallel. A new heuristicis introduced, based on a best projection criterion, which evaluatesalternative B & B trees in order to choose one for investigationin stage 2 of the algorithm. The heuristic also serves as away of implementing a quality load balancing scheme for stage2 of the algorithm. The results of experimental investigationsare reported for a range of models taken from the MIPLIB libraryof benchmark problems. 相似文献