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981.
Martin Hanke Nuutti Hyvönen Manfred Lehn Stefanie Reusswig 《BIT Numerical Mathematics》2008,48(2):245-264
We investigate the inverse source problem of electrostatics in a bounded and convex domain with compactly supported source.
We try to extract all information about the unknown source support from the given Cauchy data of the associated potential,
adopting by this previous work of Kusiak and Sylvester to the case of electrostatics. We introduce, and for the unit disk
we also compute numerically, what we call the discoidal source support, i.e., the smallest set made up by the intersection of disks within the domain, which carries a source compatible with the
given data.
AMS subject classification (2000) 35R30, 65N21 相似文献
982.
In this paper we study the Riemann and Hilbert problems of k-monogenic functions. By using Euler operator, we transform the boundary value problem of k-monogenic functions into the boundary value problems of monogenic functions. Then by the Almansi-type theorem of k-monogenic functions, we get the solutions of these problems. 相似文献
983.
This paper deals with the shape reconstruction of a viscous incompressible fluid driven by the Stokes flow. For the approximate solution of the ill-posed and nonlinear problem we propose a regularized Newton method. A theoretical foundation for the Newton method is given by establishing the differentiability of the initial boundary value problem with respect to the interior boundary curve in the sense of a domain derivative. The numerical examples show that our theory is useful for practical purpose and the proposed algorithm is feasible. 相似文献
984.
A new simplicial variable dimension restart algorithm is introduced to solve the nonlinear complementarity problem on the
product spaceS of unit simplices. The triangulation which underlies the algorithm differs from the triangulations ofS used thus far. Moreover, the number of rays along which the algorithm can leave the arbitrarily chosen starting point is
much larger. More precisely, there is a ray leading from the starting point to each vertex ofS. In caseS is the product ofn one-dimensional unit simplices the alogrithm is similar to the octahedral algorithm onR
n
having 2
n
rays. Also, the accuracy of an approximate solution in the terminal simplex of the algorithm is in general better than for
the other algorithms onS. Computational results will show that the number of iterations for the new algorithm is much less. The examples concern the
computation of equilibria in noncooperative games, exchange economies and trade models.
This author is financially supported by the Netherlands Organisation for the Advancement of Pure Research (ZWO), Grant 46-98.
This research is part of the VF-program “Equilibrium and Disequilibrium in Demand and Supply” which has been approved by the
Netherlands ministry of education and sciences. 相似文献
985.
It is well known that Moore digraphs do not exist except for trivial cases (degree 1 or diameter 1), but there are digraphs of diameter two and arbitrary degree which miss the Moore bound by one. No examples of such digraphs of diameter at least three are known, although several necessary conditions for their existence have been obtained. In this paper, we prove that digraphs of degree three and diameter k ≥ 3 which miss the Moore bound by one do not exist. © 2004 Wiley Periodicals, Inc. J Graph Theory 48: 112–126, 2005 相似文献
986.
B. D. Gelman 《Functional Analysis and Its Applications》2008,42(3):227-229
This note deals with an application of the fixed point theorem for multivalued contraction mappings to the study of degenerate differential equations with Lipschitz right-hand side and with degeneration determined by a closed surjective linear operator. 相似文献
987.
We discuss a case study of an industrial production-marketing coordination problem involving component commonality. For the product line considered, the strategic goal of the company is to move from the current low volume market to a high volume market. The marketing department believes that this can be achieved by substantially lowering the end products’ prices. However, this requires a product redesign to lower production costs in order to maintain profit margins. The redesign decision involves grouping end products into families. All products within one family use the same version of some components. This paper fits in the stream of recent literature on component commonality where the focus has shifted from inventory cost savings to production and development cost savings. Further, we consider both costs and revenues, leading to a profit maximization approach. The price elasticity of demand determines the relationship between the price level and number of units sold. Consequently, we integrate information from different functional areas such as production, marketing and accounting. We formulate the problem as a net-present-value investment decision. We propose a mixed integer nonlinear optimization model to find the optimal commonality decision. The recommendation based on our analysis has been implemented in the company. In addition, the application allows us to experimentally validate some claims made in the literature and obtain managerial insights into the trade-offs. 相似文献
988.
In this paper, we construct an augmented system of the standard monotone linear complementarity problem (LCP), and establish
the relations between the augmented system and the LCP. We present a smoothing-type algorithm for solving the augmented system.
The algorithm is shown to be globally convergent without assuming any prior knowledge of feasibility/infeasibility of the
problem. In particular, if the LCP has a solution, then the algorithm either generates a maximal complementary solution of
the LCP or detects correctly solvability of the LCP, and in the latter case, an existing smoothing-type algorithm can be directly
applied to solve the LCP without any additional assumption and it generates a maximal complementary solution of the LCP; and
that if the LCP is infeasible, then the algorithm detect correctly infeasibility of the LCP. To the best of our knowledge,
such properties have not appeared in the existing literature for smoothing-type algorithms.
This work was partially supported by the National Natural Science Foundation of China (Grant No. 10571134), the Natural Science
Foundation of Tianjin (Grant No. 07JCYBJC05200), and the Scientific Research Foundation for the Returned Overseas Chinese
Scholars, State Education Ministry. 相似文献
989.
George Boole and the origins of invariant theory 总被引:1,自引:0,他引:1
Paul R. Wolfson 《Historia Mathematica》2008,35(1):37-46
Historians have repeatedly asserted that invariant theory was born in two papers of George Boole (1841 and 1842). Although several themes and techniques of 19th-century invariant theory are enunciated in this work, in reacting to it (and thereby founding the British school of invariant theory), Arthur Cayley shifted Boole's research program. 相似文献
990.
A general monotonization method is proposed for converting a constrained programming problem with non-monotone objective function and monotone constraint functions into a monotone programming problem. An equivalent monotone programming problem with only inequality constraints is obtained via this monotonization method. Then the existing convexification and concavefication methods can be used to convert the monotone programming problem into an equivalent better-structured optimization problem. 相似文献