摘要:

AbstractThis paper extends the discussion of the relationship between optimization and electronic spreadsheet modelling. Previous authors have described two connections. These are, first, the use of spreadsheets to facilitate optimization projects and, second, the use of optimization within the spreadsheet model itself such as for cell value computation. In this paper we argue that use of the spreadsheet model for planning and design problems often may actually be viewed as interactive multi-criterion optimizationper se. This provides a third connection between optimization and spreadsheet models. We base our arguments on a simplified example arising in insurance consulting work and note other examples as well. We also propose a method for incorporating this observation into existing spreadsheet models and indicate desirable innovations in spreadsheet software.

ISSN:0160-5682    

DOI:10.1057/jors.1991.76

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis paper presents a Markov chain model for the analysis of a centralized medical record system in a large general hospital. The model is used to describe the dynamic behaviour of the age of records associated with patients' visits to a hospital and provides a method for the long-term planning of the medical record storage facilities.

ISSN:0160-5682    

DOI:10.1057/jors.1991.77

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThe Channel Tunnel, due to open in 1993, will provide a high-speed rail link between Britain and France. In this paper various scenarios are considered relating to the volume of freight which may be transported during the initial years following the opening of the tunnel. The aim is to judge whether the planned provision for freight service will be adequate in dealing with the demand. The methodology employed is that of bulk-service queueing theory; in particular, an approximate time-dependent solution to the relevant bulk-service queue is derived.

ISSN:0160-5682    

DOI:10.1057/jors.1991.78

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis paper presents the results of a survey of practising OR groups in UK organizations. The survey was conducted as part of the review procedures of Warwick University's MSc. in Operational Research. The aim was to elicit the views of OR practitioners as to the desirable content of such a course. The questionnaire was sent to 66 OR groups, of which 45 responded, and covered 75 different topics. As well as presenting the basic results, this paper explores the structure of the responses using factor analysis and attempts to classify the OR groups using cluster analysis. Comparisons are drawn with previous surveys and with the SERC OR panel recommendations.

ISSN:0160-5682    

DOI:10.1057/jors.1991.79

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractA number of interactive methods that use convex cones for solving the discrete alternative multiplecriteria problem have appeared in the literature. Convex cones are used to identify inferior alternatives based on the previous responses of the decision-maker. The aim is to identify as many inferior alternatives as possible using the cones so that the decision-maker will be required to make as few pairwise comparisons as possible.In this study we make experiments to see the effects of a number of cone generators, the selection procedure of cone generators, and the order in which pairwise comparisons are made, on the total number of pairwise comparisons. We also develop an algorithm based on the results of the experiments. Our computational experience shows that the algorithm performs well compared with algorithms that require similar information input from the decision-maker.

ISSN:0160-5682    

DOI:10.1057/jors.1991.80

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis paper discusses vehicle-routeing and scheduling problems subject to time window restriction and time-varying traffic congestion. Time-varying congestion increases the complications of the problems and, in fact, makes it challenging even to find feasible solutions. Numerous heuristics have been developed for problems with time windows only, but few for those with both time windows and time-varying congestion. We identify a simple yet robustmonotonicityproperty of arrival times, which allows us to simplify the computation. This property enhances the performance of existing heuristics. The feasibility check routines built upon this property considerably reduce computational burden.

ISSN:0160-5682    

DOI:10.1057/jors.1991.81

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractIn this paper a committee decision-making process of a convex Lagrange decomposable multi-objective optimization problem, which has been decomposed into various subproblems, is studied. Each member of the committee controls only one subproblem and attempts to select the optimal solution of this subproblem most desirable to him, under the assumption that all the constraints of the total problem are satisfied. This procedure leads to a new solution concept of a Lagrange decomposable multi-objective optimization problem, called a preferred equilibrium set. A preferred equilibrium point of a problem, for a committee, may or may not be a Pareto optimal point of this problem. In some cases, a non-Pareto optimal preferred equilibrium point of a problem, for a committee, can be considered as a special type of Pareto optimal point of this problem. This fact leads to a generalization of the Pareto optimality concept in a problem.

ISSN:0160-5682    

DOI:10.1057/jors.1991.82

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractGiven a set ofnjobs to be processed on a single machine, the problem is to find an optimal job sequence that hierarchically minimizes a bi-criterion objective function. The primary criterion is the maximum value of a general non-decreasing penalty function of job completion time, while the secondary criterion is total job flow time. An extension of Emmons's result is presented on the basis of which an improved solution procedue is developed to reduce the computational effort to find the optimal solution.

ISSN:0160-5682    

DOI:10.1057/jors.1991.83

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractIn a recent paper, Cheng considers the multiple-machine extension to a due-date assignment and scheduling problem. He implicitly assumes zero start times for all schedules (which does not ensure optimality), and overlooks the critical V-shape property for an optimal schedule (which leads him to over-estimate the effort needed to solve the problem). In this note, we correct these flaws, and also discuss the complexity of the problem and its special cases.

ISSN:0160-5682    

DOI:10.1057/jors.1991.84

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0160-5682    

DOI:10.1057/jors.1991.85

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor