bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production and Inventory Control in a Chemical Process
Authors: Ackoff Russell L. 
Published: November 2008

A great deal of research effort has been directed towards the construction of mathematical models for representing the cost of production in terms of pertinent variable factors. But having the model does not guarantee that it is economical, or even feasible, to use it for control purposes. This paper describes how a model was constructed for a complex chemical process, and why the use of the model was abandoned in favor of a simple operating scheduling rule. Operations Research, ISSN 0030-364X, was published as Journal of the Operations Research Society of America from 1952 to 1955 under ISSN 0096-3984.
Letter to the Editor—Some Thoughts on Operations Research on Municipal Operations
Authors: Horvath William J. 
Published: November 2008

The rapid expansion in the use of mathematical methods of inventory control and production scheduling brought about in the last few years through the efforts of an active group of operations analysts and econometricians has led me to reflect on the forces that determine the directions in which new developments and new ideas such as operations research are channeled. Operations Research, ISSN 0030-364X, was published as Journal of the Operations Research Society of America from 1952 to 1955 under ISSN 0096-3984.
Letter to the Editor—“Such Solutions are Very Little Solved”
Authors: Charnes A. , Cooper W. W. 
Published: November 2008

The May, 1955, issue of JORSA carried two articles which seem to call for comment—one, a serious article by Bertram Klein entitled “Direct Use of Extremal Principles in Solving Certain Optimizing Problems Involving Inequalities” and two, a short, humorous one by Paul Gunther entitled “Use of Linear Programming in Capital Budgeting.” We believe that readers of JORSA will be well advised to treat the humorous article seriously and the serious article humorously. Operations Research, ISSN 0030-364X, was published as Journal of the Operations Research Society of America from 1952 to 1955 under ISSN 0096-3984.
An Analog Solution of Programming Problems
Authors: Ablow C.M. , Brigham Georges 
Published: November 2008

A simple, fast, and accurate method for solving (static) programming problems is presented. The method is particularly well adapted to electronic analog computers. The problem is interpreted as the asymptotic solution of a problem in the dynamics of a massless particle. The “particle” is considered to move in n-space away from those regions forbidden by the constraints of the problem and toward optimization of the criterion function. Constraint or criterion functions need not be linear but merely expressible with available computer components. The speed with which a solution is attained is under the operator's control. Operations Research, ISSN 0030-364X, was published as Journal of the Operations Research Society of America from 1952 to 1955 under ISSN 0096-3984.
On a Congestion Problem in an Aircraft Factory
Authors: Brigham Georges 
Published: November 2008

This is a study of the optimum number of clerks to be placed behind service counters. It involves queuing theory and was solved in two parts: First, we considered the counter from the customers' side, the “obverse” queue. Observational data showed that arrivals at the counter occur at random, the order of serving was random, and the distribution of the service times was exponential, so that Erlang's “C” formula for the probability that a customer has to wait applied. A formula is derived and graphed that shows the optimum number of clerks to be used behind the counter and the over-all minimum cost caused by waiting on the part of the customers and the clerks as a function of the queue input and the ratio of the cost of the customers' time to that of the clerks'. Second, the queue from the clerks' side was considered, that is, from the “reverse” queue. Clerks' time spent waiting for customers to appear is not altogether lost, if they can do work behind the counter. What happens to the clerks is governed by the characteristics of the “obverse” queue. From that is derived the probability distribution of the clerks' waiting time, considering the clerks to form a queue, as customers do. With this we calculate the saving in clerks' time that can be effected subject to the limitations of the shortest free period and the total length of time that can be used productively. This saving can then be subtracted from the cost computed in the first part of the study. The results obtained are applicable to any queuing operation which has the same characteristics. Operations Research, ISSN 0030-364X, was published as Journal of the Operations Research Society of America from 1952 to 1955 under ISSN 0096-3984.
An Appreciation of Systems Analysis
Authors: Hitch Charles 
Published: November 2008

Military systems analysis is an extension of operations-research techniques of World War II to problems of broader context and longer range—e.g., force composition and development as well as operations decisions. Greater complexity is inevitable as we attempt analyses to aid decisions affecting more distant time periods: growth in number of relevant variables, compounding of uncertainties; increased importance of enemy reactions; complications of time phasing, the need for a broader concept of criteria Techniques available to the systems analyst for dealing with these complexities are less than satisfactory. “Factoring” is inevitable. All routine or mechanistic approaches are deficient; e.g., expected value and minimax criteria. Design and criteria problems are of dominant importance. The systems analyst may have to be content with better rather than optimal solutions, or with devising and costing sensible methods of hedging; or merely with discovering critical sensitivities. He has an important role as inventor of systems. The difficulties of systems analysis are rooted in the nature of the military problems. Other methods—e.g, piecemeal analysis or intuition—do not escape them and have limitations of their own. Military systems analysis provides a framework for combining the knowledge of experts in many fields to reach solutions which transcend any individual expert's judgment. Operations Research, ISSN 0030-364X, was published as Journal of the Operations Research Society of America from 1952 to 1955 under ISSN 0096-3984.
Expectancy of Multiple Vehicular Breakdowns in a Tunnel
Authors: Edie Leslie C. 
Published: November 2008

One of the principal operating problems at vehicular tunnels is that of traffic stoppages resulting from disabled vehicles. These vehicles break down for such various reasons as flat tires, overheating, no gasoline, and mechanical failures. The stoppages are particularly troublesome in peak traffic periods when the full capacity of the tunnel may be badly needed. Subaqueous tunnels consist of two-lane tubes, so that a stoppage in one lane immediately reduces the capacity of the tube affected by one-half. Actually, the reduction in capacity is even greater than one-half, since the movement of traffic in the unstopped lane is reduced by the operations necessary to remove the disabled vehicle. Operations Research, ISSN 0030-364X, was published as Journal of the Operations Research Society of America from 1952 to 1955 under ISSN 0096-3984.
On Operations Analysis
Authors: Roy Robert H. 
Published: November 2008

Among the staff elements of organization which have multiplied in recent years are those engaged in the analysis of operations. Their tasks are described variously as operations research, industrial engineering, operations analysis, operations evaluation, etc., terms which are not quite synonymous nor altogether acceptable to jealous practitioners in one or another of these fields. Here, however, they will mean the same thing staff engaged in the analysis of operations with the mission of improving performance. Their goal is research rather than service. This paper was presented as an invited address to the session on Operations Research and the Firm at the Fourth Annual Meeting of the Society, Washington, D.C., May 10, 1956.
The Theory of Search. I. Kinematic Bases
Authors: Koopman B. O. 
Published: November 2008

In the conventional search situation, there are three general features. I The kinematic bases, involving the positions, geometrical configurations, and motions in the searchers and targets, with particular reference to the statistics of their contacts and the probabilities of their reaching various specified relative positions. II The probabilistic behavior of the instrument of detection (eye, radar, sonar, etc) when making a given passage relative to the target. III The over-all result—the probability of contact under general stated conditions, along with the possibility of optimizing the results by improving the methods of directing the search. The present paper is devoted to the first feature, and is intended to provide the kinematic bases of the theory. It studies fairly simple cases of relative motion and draws inspiration from the kinetic theory of matter. The second paper, entitled Target Detection, will deal with the second feature. It is based on the methods of survival probabilities familiar in actuarial studies, and is, it must be emphasized, confined to the case of independent trials. A third paper will deal with an important aspect of the third feature, and will be entitled The Optimum Distribution of Searching Effort. It represents the continuous extension of a paper of a similar title published by the author in Operations Research in February 1953.
Heuristics for a One-Warehouse Multiretailer Distribution Problem with Performance Bounds
Authors: Herer Yale , Roundy Robin 
Published: November 2008

We investigate the one warehouse multiretailer distribution problem with traveling salesman tour vehicle routing costs. We model the system in the framework of the more general production/distribution system with arbitrary non-negative monotone joint order costs. We develop polynomial time heuristics whose policy costs are provably close to the cost of an optimal policy. In particular, we show that given a submodular function which is close to the true order cost then we can find a power-of-two policy whose cost is only moderately greater than the cost of an optimal policy. Since such submodular approximations exist for traveling salesman tour vehicle routing costs we present a detailed description of heuristics for the one warehouse multiretailer distribution problem. We formulate a nonpolynomial dynamic program that computes optimal power-of-two policies for the one warehouse multiretailer system assuming only that the order costs are non-negative monotone. Finally, we perform computational tests which compare our heuristics to optimal power of two policies for problems of up to sixteen retailers. We also perform computational tests on larger problems; these tests give us insight into what policies one should employ.
A Heuristic for a Scheduling Problem with Communication Delays
Authors: Munier Alix , König Jean-Claude 
Published: November 2008

This paper addresses a scheduling problem with interprocessor communication delays: the jobs and the communication delays are of unit length. The number of processors is unbounded. The aim is to minimize the makespan. We develop a new list scheduling heuristic and we prove that its worst-case relative performance is 4/3.
Performance Measures and Schedules in Periodic Job Shops
Authors: Lee Tae-Eog , Posner Marc E. 
Published: November 2008

This paper discusses the periodic job shop scheduling problem, a problem where an identical mixture of items, called a minimal part set (MPS), is repetitively produced. The performance and behavior of schedules are discussed. Two basic performance measures, cycle time and makespan, are shown to be closely related. The minimum cycle time is identified as a circuit measure in a directed graph. We establish that there exists a class of schedules that minimizes cycle time and repeats an identical timing pattern every MPS. An algorithm is developed to construct such schedules. We show that minimizing the makespan as a secondary criterion, minimizes several other performance measures. For makespan minimization, we examine earliest starting schedules where each operation starts as soon as possible. We characterize the cases where after a finite number of MPSs, the earliest starting schedule repeats an identical timing pattern every fixed number of MPSs. We also develop a modification to an earliest starting schedule that repeats an identical timing pattern every MPS when the beginning operations on the machines are delayed.
Cellular Manufacturing: A Statistical Review of the Literature (1965–1995)
Authors: Reisman Arnold , Kumar Ashok , Motwani Jaideep , Cheng Chun Hung 
Published: November 2008

This paper is both an extension and an expansion of two earlier studies concerned with the direction of OR/MS research as reported in its archival literature (Reisman and Kirschnick [Reisman, A., F. Kirshnick. 1994. The devolution of OR/MS: Implications from a statistical content analysis of papers in flagship journals. Opns. Res. 42(4) 577–588], [Reisman, A., F. Kirshnick. 1995. Research strategies used by OR/MS workers as shown by an analysis of papers in flagship journals. Opns. Res. 43(5) 731–739.]). All of these papers provide a content analysis of the OR/MS archival journals. However, this paper focuses on the entire life-cycle literature of Cellular Manufacturing as a module of OR/MS. It addresses the research strategy employed by, and the theory-vs-applied orientation exhibited by, the authors. In all, 235 articles, starting in 1969, were reviewed and classified on a five-point scale, ranging from pure theory to bonafide applications. Secondly, the articles were classified in terms of seven types of research processes used by authors. Next, statistical correlations were performed relating data from the above classifications. The findings show that the literature is dominated (94 papers, or 40%) by articles classified as pure theory using synthetic “data” and the ripple or incremental process as a basic research strategy. During the first decade of cellular manufacturing research (1969 through 1978) this subset accounted for but 4 out of 42 (or 9.5%) of the papers published, whereas during the most recent decade it accounted for 81 papers (or 47.4%) of the literature. Lastly, the article raises questions about the future of cellular manufacturing research vis-à-vis other related subject matter.
Optimal Control of a Multiclass, Flexible Queueing System
Authors: Gans Noah , van Ryzin Garrett 
Published: November 2008

We consider a general class of queueing systems with multiple job types and a flexible service facility. The arrival times and sizes of incoming jobs are random, and correlations among the sizes of arriving job types are allowed. By choosing among a finite set of configurations, the facility can dynamically control the rates at which it serves the various job types. We define system work at any given time as the minimum time required to process all jobs currently in the backlog. This quantity is determined by solving a linear program defined by the set of processing configurations. The problem we study is how to dynamically choose configurations to minimize the time average system work. Using bounds and heuristics, we analyze a class of service policies that is provably asymptotically optimal as system utilization approaches one, as well as a policy that in numerical studies performs near-optimally in moderate traffic. Our analysis also yields a closed-form expression for the optimal, average work in heavy traffic. This general problem has a number of applications in job shop and flexible manufacturing, in service organizations, and in the management of parallel processing and distributed database systems.
Optimal Placement of Add/Drop Multiplexers: Heuristic and Exact Algorithms
Authors: Sutter Alain S. , Vanderbeck François , Wolsey Laurence 
Published: November 2008

We study a problem that has arisen recently in the design of telecommunications transmission networks at France Telecom. Given a set of centers in a city or conglomeration linked together on a ring architecture, given the expected demands between the centers and an essentially unlimited availability of rings of fixed capacity on the network, assign demand pairs and corresponding add/drop multiplexers to the rings so as to satisfy the demands and minimize the number of “costly” multiplexers installed. Heuristics based on simulated annealing have been developed for the basic problem and several variants. France Telecom is particularly interested in validating the effectiveness of the heuristics. An exact algorithm based on integer column generation is shown to provide tight performance guarantees, and in most cases to give provable minimum cost solutions. Column generation is used even though the subproblems are strongly NP-hard and are solved by standard mixed integer programming software. In addition, the Master Problems involve both integer columns and integer variables, whereas these are 0–1 in most reported applications.
Airline Network Design
Authors: Lederer Phillip J. , Nambimadom Ramakrishnan S. 
Published: November 2008

The goal of this paper is to understand choices of networks and schedules by a profit maximizing airline. By “network” we mean the routing pattern for planes and by “schedule” we mean the frequency of service between cities and the amount of time put into the schedule to assure on-time arrival. This paper analyzes network and schedule choice using an “idealized” model that permits derivation of analytic, closed form expressions for airline and passenger costs. Many important conclusions are obtained. It is optimal for a profit maximizing airline to design its network and schedule to minimize the sum of airline and passenger costs. Profit maximizing choice of schedule frequency depends on the network. Direct service has lower schedule frequency than other networks. Parametric studies are performed on the effect of distance between cities, demand rate, and the number of cities served on the choice of the network. Some conclusions are: (1) If the distance between cities is very small, then direct service is optimal; otherwise, other networks, such as hub and spoke are optimal. (2) Similarly, for very high demand rates, direct service is optimal; and for intermediate values, hub and spoke is optimal. (3) If the number of cities is small, direct service dominates; and if it is large, hub and spoke is optimal. We note that any airline's schedule includes safety time as a buffer against delays, and we demonstrate that schedule reliability is highest for direct routing. Surprisingly, the amount of time that is added to the schedule to buffer delays is relatively less in direct networks than in other networks. This can explain the superior on-time performance and high equipment utilization of direct carriers such as Southwest Airlines.
Lower Bounds for the Quadratic Assignment Problem Based upon a Dual Formulation
Authors: Hahn Peter , Grant Thomas 
Published: November 2008

A new bounding procedure for the Quadratic Assignment Problem (QAP) is described which extends the Hungarian method for the Linear Assignment Problem (LAP) to QAPs, operating on the four dimensional cost array of the QAP objective function. The QAP is iteratively transformed in a series of equivalent QAPs leading to an increasing sequence of lower bounds for the original problem. To this end, two classes of operations which transform the four dimensional cost array are defined. These have the property that the values of the transformed objective function Z′ are the corresponding values of the “old” objective function Z, shifted by some amount C. In the case that all entries of the transformed cost array are nonnegative, then C is a lower bound for the initial QAP. If, moreover, there exists a feasible solution U to the QAP, such that its value in the transformed problem is zero, then C is the optimal value of Z and U is an optimal solution for the original QAP. The transformations are iteratively applied until no significant increase in constant C as above is found, resulting in the so called Dual Procedure (DP). Several strategies are listed for appropriately determining C, or equivalently, transforming the cost array. The goal is the modification of the elements in the cost array to obtain new equivalent problems that bring the QAP closer to solution. In some cases the QAP is actually solved, though solution is not guaranteed. The close relationship between the DP and the Linear Programming formulation of Adams and Johnson is presented. The DP attempts to solve Adams and Johnson's CLP, a continuous relaxation of a linearization of the QAP. This explains why the DP produces bounds close to the optimum values for CLP calculated by Johnson in her dissertation and by Resende, et al. in their Interior Point Algorithm for Linear Programming. The benefit of using DP within a branch-and-bound algorithm is described. Then, two versions of DP are tested on the Nugent test instances from size 5 to size 30, as well as several other test instances from QAPLIB. These compare favorably with earlier bounding methods.
Designing Portfolios of Financial Products via Integrated Simulation and Optimization Models
Authors: Consiglio Andrea , Zenios Stavros A. 
Published: November 2008

We analyze the problem of debt issuance through the sale of innovative financial products. The problem is broken down to questions of designing the financial products, specifying the debt structure with the amount issued in each product, and determining an optimal level of financial leverage. We formulate a hierarchical optimization model to integrate these three issues and provide constructive answers. Input data for the models are obtained from Monte Carlo simulation procedures that generate scenarios of holding period returns of the designed products. The hierarchical optimization model is specialized for the problem of issuing a portfolio of callable bonds to fund mortgage assets. The upper level optimization program is multimodal, and a tabu search procedure is developed for its solution. Empirical results illustrate the efficacy of the developed models in designing the appropriate structure of the callable bonds and making optimal allocations of equity and debt among the designed products. Computational results with the implementation of tabu search—on both serial and parallel computers—are also presented.