Operations Research

最新文章

• SCHEDULING NETWORKS OF QUEUES - HEAVY TRAFFIC ANALYSIS OF A MULTISTATION CLOSED NETWORK AI翻译
  作者：CHEVALIER, PB; WEIN, LM
  摘要：We consider the problem of finding an optimal dynamic priority sequencing policy to maximize the mean throughput rate in a multistation, multiclass closed queueing network with general service time distributions and a general routing structure. Under balanced heavy loading conditions, this scheduling problem can be approximated by a control problem involving Brownian motion. Although a unique. closed-form solution to the Brownian control problem is not derived. an analysis of the problem leads...
• A FAMILY OF SEARCH DIRECTIONS FOR KARMARKARS ALGORITHM AI翻译
  作者：ANSTREICHER, KM; WATTEYNE, P
  作者单位：Universite Catholique Louvain
  摘要：We consider a new family of search directions for the standard form variant of Karmarkar's projective linear programming algorithm. The family includes the usual projected gradient direction, and also a direction first proposed by Mike Todd. We prove that any choice from the family preserves the algorithm's polynomial-time complexity. We then examine the computational behavior of the algorithm using different choices of directions. Although the theoretical complexity is the same for the differ...
• BEST-1ST SEARCH METHODS FOR CONSTRAINED 2-DIMENSIONAL CUTTING STOCK PROBLEMS AI翻译
  作者：VISWANATHAN, KV; BAGCHI, A
  作者单位：Indian Institute of Management (IIM System); Indian Institute of Management Calcutta; New Jersey Institute of Technology
  摘要：Best-first search is a widely used problem solving technique in the field of artificial intelligence. The method has useful applications in operations research as well. Here we describe an application to constrained two-dimensional cutting stock problems of the following type: A stock rectangle S of dimensions (L, W) is supplied. There are n types of demanded rectangles r1, r2,..., r(n), with the ith type having length l(i), width w(i), value v(i) and demand constraint b(i). It is required to ...
• EXACT AND APPROXIMATE EVALUATION OF BATCH-ORDERING POLICIES FOR 2-LEVEL INVENTORY SYSTEMS AI翻译
  作者：AXSATER, S
  摘要：We consider a two-level inventory system with one warehouse and N identical retailers. Lead times (transportation times) are constant and the retailers face independent Poisson demand. In a previous paper, we derived a recursive procedure for determining the policy costs for an average item in case of one-for-one replenishment policies. In this paper, we show how these results can be used for the exact or approximate evaluation of more general policies where both the retailers and the warehous...
• STOCHASTIC SINGLE-MACHINE SCHEDULING WITH QUADRATIC EARLY-TARDY PENALTIES AI翻译
  作者：MITTENTHAL, J; RAGHAVACHARI, M
  摘要：We address the problem of scheduling n jobs on a single machine, which is subject to random breakdowns, to minimize an expected sum of nonregular penalty functions. A simple recourse model is considered when the penalty function is the squared deviation of job completion times from a common due date, and a deterministic equivalent objective function is developed. Characterizations of optimal schedules for this quadratic objective function are established both when the common due date is a deci...
• ON THE MINIMIZATION OF THE MAKESPAN SUBJECT TO FLOWTIME OPTIMALITY AI翻译
  作者：ECK, BT; PINEDO, M
  作者单位：Columbia University
  摘要：When scheduling n jobs on m identical machines in parallel, two performance criteria are of particular interest: the makespan (the completion time of the last job) and the flowtime (the sum of the completion times of all n jobs). Whereas minimizing makespan is NP-hard, many schedules minimize flowtime, and they are easy to characterize. This paper considers the problem of minimizing the makespan among flowtime-optimal schedules. Heuristics have appeared in the literature that result in flowtim...
• A RANDOMIZATION RULE FOR SELECTING FORECASTS - COMMENT AI翻译
  作者：CLEMEN, RT
• A RANDOMIZATION RULE FOR SELECTING FORECASTS - REPLY AI翻译
  作者：FOSTER, DP; VOHRA, RV
  作者单位：University System of Ohio; Ohio State University
• EXPLORATORY MODELING FOR POLICY ANALYSIS AI翻译
  作者：BANKES, S
  摘要：Exploratory modeling is using computational experiments to assist in reasoning about systems where there is significant uncertainty. While frequently confused with the use of models to consolidate knowledge into a package that is used to predict system behavior, exploratory modeling is a very different kind of use, requiring a different methodology for model development. This paper distinguishes these two broad classes of model use, describes some of the approaches used in exploratory modeling...
• MEASURING PERFORMANCE IN A MULTIPRODUCT FIRM - AN APPLICATION TO THE UNITED-STATES-POSTAL-SERVICE AI翻译
  作者：BRADLEY, MD; BARON, DM
  摘要：Measuring performance in a multiproduct firm is difficult because of the complex nature of the firm's output. We present an approach to measuring performance, called operating efficiency, which is the ratio of aggregate output to aggregate resource use. We describe how to calculate operating efficiency for a multiproduct organization and demonstrate how it can be used to understand why performance varies across plants and/or through time. Our application of operating efficiency to the U.S. Pos...