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作者：Tassiulas, L
作者单位：University System of Maryland; University of Maryland College Park
摘要：Demands for service arrive at random times, in random locations, in a region of the plane. The service time of each demand is random. A server that travels with constant speed moves from demand to demand providing service. The server spends its time either in providing service or in traveling. The objective is to route the server, based on the location of the current demands on the plane and the anticipated demand arrivals, such that the time spent in traveling is minimal and the service is pr...
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作者：Thompson, RG; Dharmapala, PS; Gatewood, EJ; Macy, S; Thrall, RM
作者单位：University of Houston System; University of Houston; University of Houston System; University of Houston; Rice University
摘要：The University of Houston (UH) Small Business Development Centers (SBDCs) were analyzed by Data Envelopment Analysis (DEA) and Assurance Region (AR) methods. The DEA/AR analyses were made for 11 DMUs in 1990 and 1991 and for 13 DMUs in 1992. The DEA ratio (CCR) method was applied to Model I in all three years; unique optimal solutions to the DEA-inefficient DMUs were verified. Also, ARs were applied to eliminate some DEA-efficient DMUs requiring unreasonable multipliers to maximize efficiency....
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作者：Wein, LM; Zenios, SA
作者单位：Massachusetts Institute of Technology (MIT)
摘要：We study pooled (or group) testing as a cost-effective alternative for screening donated blood products (sera) for HIV; rather than test each sample individually, this method combines various samples into a pool, and then tests the pool. A group testing policy specifies an initial pool size, and based on the HIV test result, either releases all samples in the pool for transfusion, discards all samples in the pool, or divides the pool into subpools for further testing. We develop a hierarchical...
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作者：Hassin, R
摘要：The problem we treat is defined on a graph where each node is associated with a variable and there are loss functions defined on the arcs, depending on the difference between the corresponding node variables. The objective is to compute values for the node variables so as to minimize the sum of losses. We exploit the relation between this problem and network flows optimization and use it in developing an approximation algorithm for the problem A main application of the problem is the synchroni...
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作者：Gallego, G; Queyranne, M; SimchiLevi, D
作者单位：University of British Columbia; Northwestern University
摘要：We consider two economic order quantity models where multiple items use a common resource. In the tactical model, the objective is to establish and coordinate order quantities to minimize total inventory ordering and carrying costs without, ever exceeding a capacity constraint on the resource. In the strategic model, the objective is to establish and coordinate order quantities to minimize the average cost which includes in addition to the ordering and inventory costs, a cost proportional to t...
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作者：DeWolf, D; Smeers, Y
作者单位：Universite Catholique Louvain
摘要：We develop an algorithm to solve the problem of the optimal dimensioning of a fluid (gas or water) transmission network when the topology of the network is known. The pipe diameters must be chosen to minimize the sum of the investment and operating costs. This two stage problem is solved by application of the bundle method for nonsmooth optimization. The validity of the approach is tested on a problem corresponding to a real situation: the optimal design of a reinforcement of the Belgian gas n...
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作者：Sainfort, F; Deichtmann, JM
作者单位：University of Wisconsin System; University of Wisconsin Madison
摘要：The standard decomposition theorem for additive and multiplicative utility functions (Pollak 1967, Keeney 1974) assumes that the outcome set is a whole product set. In this paper this assumption is relaxed, and the question of whether or not a natural revision of this theorem necessarily holds is investigated. This paper proves that two additional conditions are needed for the decomposition theorem to hold in the context where the outcome set is a subset of a Cartesian product. It is argued th...
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作者：Serafini, P
摘要：This scheduling model is derived from the real problem of scheduling looms in a textile industry. Jobs may be independently split. over several specified machines, and preemption is allowed. Deadlines are specified for each job, and jobs are assumed to be available. It is shown that minimizing maximum weighted tardiness can be done in polynomial time. The case of uniform machines (as in the considered application) can be modeled as a network flow, and minimization of maximum tardiness can be d...
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作者：Cooper, RB; Niu, SC; Srinivasan, MM
作者单位：University of Tennessee System; University of Tennessee Knoxville; University of Texas System; University of Texas Dallas
摘要：We consider the classical polling model: queues served in cyclic order with either exhaustive or gated service, each with its own distinct Poisson arrival stream, service-time distribution, and switchover-time (the server's travel time from that queue to the next) distribution. Traditionally, models with zero switchover times (the server travels at infinite speed) and nonzero switchover times have been considered separately because of technical difficulties reflecting the fact that in the latt...
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作者：Veatch, MH; Wein, LM
作者单位：Massachusetts Institute of Technology (MIT)
摘要：A single machine produces several different classes of items in a make-to-stock mode. We consider the problem of scheduling the machine to regulate finished goods inventory, minimizing holding and backorder, or holding and lost sales costs. Demands are Poisson, service times are exponentially distributed, and there are no delays or costs associated with switching products. A scheduling policy dictates whether the machine is idle or busy and specifies the job class to serve in the latter case. ...
