摘要:

AbstractIn this paper evidence is presented regarding the degree to which social reforms have been systematically managed by the Public Sector in Greece between 1975-1992. The findings reported here concur with the findings of others that, by and large, in developing countries, important social reforms tend not to be systematically handled. A twofold explanation is advanced for what seems to be an inverse relationship between the importance of social reforms and the use of OR/MS techniques for their management. First, the subsidiary role of OR/MS techniques in both developing and developed countries is partly due to the conflict-ridden and complex nature of important social reforms, which are not as amenable to systematic analysis as small-scale reforms. It is also partly due to the competitive nature of liberal democracies which compels governments to use social policies not only in a problem-solving mode but also in a tactical mode. Secondly, the low degrees of bureaucratization and rationalization that characterize developing countries, in particular, account for seeing social reforms not so much as manifestations of rational calculation designed to solve problems but as political tools in the service of their masters. It is concluded that OR/MS may be useful in developing countries not so much for its techniques as for its ideology; not for what it is but for what it stands for.

ISSN:0160-5682    

DOI:10.1057/jors.1994.164

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractIn this paper, a mathematical model of the Ingot Mill in the Portland Aluminium Smelter is developed. The Ingot Mill, one of the last main plants involved in the aluminium production process at Portland, plays a critical role with respect to its ability to handle the output from the potrooms (in the form of crucibles of molten aluminium). Should its capacity to handle crucibles from the potrooms be below the level required, the entire plant can be disrupted causing substantial cost increases. The mixed integer linear programming model developed provides considerable assistance to plant operators in their quest to meet the throughput demand placed on them by potrooms and to arranging the proper scheduling of regular maintenance downtime for plant equipment.

ISSN:0160-5682    

DOI:10.1057/jors.1994.165

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractAudit staff planning has been a challenging problem for accounting, auditing and real estate firms. This paper presents a mathematical model and a solution methodology for determining the minimum-cost analysts assignment, when analysts should travel from geographically dispersed locations to evaluate assets of an insolvent Saving and Loan institution. Computational experiments with the solution algorithm on 27 randomly generated projects show (a) that the solution methodology efficiently generates an optimal solution, and (b) provides the decision maker with alternative next best plans throughex postsensitivity analysis. Although specific, variations of the model and algorithm presented here can be applied to a variety of audit staff assignment problems in accounting and real estate firms.

ISSN:0160-5682    

DOI:10.1057/jors.1994.166

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractFlexible manufacturing systems represent an advanced class of automated manufacturing systems. Because of the complexity and dynamic behaviour of such systems, simulation modelling is becoming a popular method of facilitating FMS design and determining operational strategies. This paper illustrates the use of activity cycle diagrams as a graphical method for developing simulation models for two existing flexible manufacturing systems. A description of this graphical method is given, and some simulation models are presented. Various versions of the models were developed for each configuration because of the different production processes performed in the systems. The influence of two different software packages (SIMFACTORY II.5 and VS7), which were used for the development of computer models based on activity cycle diagram conceptual models, is illustrated. Different models were developed for the same configurations and process plans, to allow for the level of detail that can be modelled by each software package. The conclusions discuss to what extent activity cycle diagrams are suitable for the development of conceptual FMS simulation models.

ISSN:0160-5682    

DOI:10.1057/jors.1994.167

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThis paper studies the assignment ofMunique machines toMequally spaced locations along a linear material handling track with the objective of minimizing the cost of (jobs) backtracking (i.e. moving upstream). Because of the arrangement of machines and restrictions imposed by the sequence of operations for each job, some jobs may have to backtrack to complete required processing on different machines. This problem is formulated as a quadratic assignment problem. An optimal solution to a problem with largeMis computationally intractable. The backtracking distance matrix in problems involving equally-spaced machine locations in one dimension is seen to possess some unique characteristics called amoebic properties. Ten amoebic properties have been identified and exploited to devise a heuristic and a lower bound on the optimal solution. Results which describe the performance of the heuristic and the lower bound are presented.

ISSN:0160-5682    

DOI:10.1057/jors.1994.168

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractWe develop a robust optimization model for planning power system capacity expansion in the face of uncertain power demand. The model generates capacity expansion plans that are both solution and model robust. That is, the optimal solution from the model is‘almost’optimal for any realization of the demand scenarios (i.e. solution robustness). Furthermore, the optimal solution has reduced excess capacity for any realization of the scenarios (i.e. model robustness). Experience with a characteristic test problem illustrates not only the unavoidable trade-offs between solution and model robustness, but also the effectiveness of the model in controlling the sensitivity of its solution to the uncertain input data. The experiments also illustrate the differences of robust optimization from the classical stochastic programming formulation.

ISSN:0160-5682    

DOI:10.1057/jors.1994.169

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractIncreasingly, it is becoming recognized that interactive solution methods should provide not only a solution to a multiple criteria decision making (MCDM) problem, but also the opportunity for decision makers to learn about their own preferences. In this paper, we describe an experiment that examines three MCDM solution methods and the process of converging on a final solution. Twenty-four management students participated in the experiment and were required to solve two completely different MCDM problems. Within this experimental framework, we examined the use of a two-stage approach to decision making. Both quantitative and qualitative results are presented. Preferences among the different solution methods vary significantly. Several conclusions are drawn concerning the desirable features of interactive MCDM solution methods.

ISSN:0160-5682    

DOI:10.1057/jors.1994.170

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThis paper is concerned with some aspects of direct and indirect sales rates of products, and with a model based on the sales matrix. The purpose of this consideration is to determine, through indirect sales rates, the structure of sales and to construct a model which may be used for planning and forecasting goals. In other words, by means of the sales matrix, or a model based on it, we can estimate the future sales movements. This can be done either from the assumption that past relations will be kept approximately in the same proportions, or that they will change in the future. In each case all the changes can be described through the system based on the sales matrix.

ISSN:0160-5682    

DOI:10.1057/jors.1994.171

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThis paper proposes a global approach for solving mixed 0-1 programming problems containing convex or separable continuous functions. Given a mixed 0-1 polynomial termz=x1x2, ...xng(Y) wherex1,x2,...,xnare 0-1 integer variables andg(Y) is a convex or a separable continuous function, we can transformzinto a set of inequalities wherex1,x2,...,xnandg(Y) are separated from each other. Based on this transformation, the original mixed 0-1 program can then be solved by a branch-and-bound method to obtain a global optimum.

ISSN:0160-5682    

DOI:10.1057/jors.1994.172

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractIn this note, single machine scheduling and minimizing absolute flow time deviation (TAFD) are considered. The relationship between this problem and the mean absolute deviation of job completion times about a common due date (MAD) is discussed. Based on the MAD problem optimal solutions of the TAFD problem are given. Furthermore, the generalization of the problem to the multiple machine case is discussed and an efficient algorithm for generating many optimal solutions of the problem, in the multi-machine case, is given.

ISSN:0160-5682    

DOI:10.1057/jors.1994.173

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor