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991.
The existence of infinitely many solutions of the following Dirichlet problem for p-mean curvature operator:
is considered, where Θ is a bounded domain in R
n
(n>p>1) with smooth boundary ∂Θ. Under some natural conditions together with some conditions weaker than (AR) condition, we prove that the above problem
has infinitely many solutions by a symmetric version of the Mountain Pass Theorem if
.
Supported by the National Natural Science Foundation of China (10171032) and the Guangdong Provincial Natural Science Foundation
(011606). 相似文献
992.
The set of all group relaxations of an integer program contains certain special members called Gomory relaxations. A family
of integer programs with a fixed coefficient matrix and cost vector but varying right hand sides is a Gomory family if every
program in the family can be solved by one of its Gomory relaxations. In this paper, we characterize Gomory families. Every
TDI system gives a Gomory family, and we construct Gomory families from matrices whose columns form a Hilbert basis for the
cone they generate. The existence of Gomory families is related to the Hilbert covering problems that arose from the conjectures
of Seb?. Connections to commutative algebra are outlined at the end.
Received: May 17, 2001 / Accepted: February 7, 2002
Published online: April 24, 2003
RID="⋆"
ID="⋆" Research partially supported by NSF grant DMS-0100141. 相似文献
993.
In this paper, we investigate the exact distribution of the waiting time for ther-th ℓ-overlapping occurrence of success-runs of a specified length in a sequence of two state Markov dependent trials. The
probability generating functions are derived explicitly, and as asymptotic results, relationships of a negative binomial distribution
of orderk and an extended Poisson distribution of orderk are discussed. We provide further insights into the run-related problems from the viewpoint of the ℓ-overlapping enumeration
scheme. We also study the exact distribution of the number of ℓ-overlapping occurrences of success-runs in a fixed number
of trials and derive the probability generating functions. The present work extends several properties of distributions of
orderk and leads us a new type of geneses of the discrete distributions. 相似文献
994.
Asger Hobolth Jan Pedersen Eva B. Vedel Jensen 《Annals of the Institute of Statistical Mathematics》2003,55(2):227-242
In this paper we propose a flexible continuous parametric shape model for star-shaped planar objects. The model is based on
a polar Fourier expansion of the normalized radius-vector function. The expected phase amplitudes are modelled by a simple
regression with parameters having nice geometric interpretations. The suggestedgeneralized p-order model is an extension of first- and second-order Gaussian shape models, and in particular the Gaussian assumption is relaxed. The
statistical analysis is straightforward, as demonstrated by an application concerning shape discrimination of two cell nuclei
populations. 相似文献
995.
996.
997.
This paper defines a set of material compatibility constraints for use in order promising mixed integer programs. The constraints always represent a necessary condition for compatibility and, in certain cases, are both necessary and sufficient. The underlying analysis represents incompatibilities using bipartite graphs and applies results from the perfectly matchable subgraph polytope. 相似文献
998.
F J Vasko D D Newhart K L StottJr F E Wolf 《The Journal of the Operational Research Society》2003,54(1):11-20
The traditional, uncapacitated facility location problem (UFLP) seeks to determine a set of warehouses to open such that all retail stores are serviced by a warehouse and the sum of the fixed costs of opening and operating the warehouses and the variable costs of supplying the retail stores from the opened warehouses is minimized. In this paper, we discuss the partial coverage uncapacitated facility location problem (PCUFLP) as a generalization of the uncapacitated facility location problem in which not all the retail stores must be satisfied by a warehouse. Erlenkotter's dual-ascent algorithm, DUALOC, will be used to solve optimally large (1600 stores and 13?000 candidate warehouses) real-world implemented PCUFLP applications in less than two minutes on a 500?MHz PC. Furthermore, a simple analysis of the problem input data will indicate why and when efficient solutions to large PCUFLPs can be expected. 相似文献
999.
S A Starbird 《The Journal of the Operational Research Society》2003,54(1):32-39
Coordinated replenishment is a supply chain policy that affects many operational performance measures, including cost, lead time, and quality. In this paper, we develop a mathematical model of a simplified supply chain in which conformance quality is one of the supplier's decision variables and both the supplier and its customer are trying to minimize expected annual cost. Our expected cost model includes the important quality costs (appraisal, prevention, internal failure, and external failure) as well as holding, set-up, and ordering costs. Our results indicate that coordination leads to a decline in total cost but that coordination does not necessarily lead to an improvement in quality. In other words, buyers who are using coordinated replenishment may be trading higher quality for lower cost. 相似文献
1000.
In a recent paper, Hwang and Hahn considered inventory replenishment problems for an item with an inventory-level-dependent demand rate and a fixed lifetime. They developed an EQQ model under the situation of considering the first-in–first-out (FIFO) issuing policy. First, this paper reconsiders Hwang and Hann's problem by employing the last-in–first-out (LIFO) issuing policy, which is more practical in the retail industry. An inventory model is developed. Secondly, the concavity of the objective function is proved. Thirdly, this paper presents conditions where the present model has a unique optimal solution and a method for finding the global optimal solution. A simple solution procedure and sensitivity analyses of parameters are also provided. 相似文献