ISSN:0160-5682    

DOI:10.1057/jors.1964.53

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

ISSN:0160-5682    

DOI:10.1057/jors.1964.54

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

摘要:

AbstractThis paper describes the installation of a planning system in a food factory, based on the use of linear programming. Owing to the seasonal nature of many of the parameters, it is essential to use a multi-period model.The formulation of the L.P. model is discussed in some detail. This includes a considerable number of restrictions of a commercial rather than a physical nature.A particular aspect of the application is the way in which the model is used, in slightly different forms, at the three distinct stages of the planning process.Some of the practical difficulties encountered in implementing the solution are discussed.

ISSN:0160-5682    

DOI:10.1057/jors.1964.55

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

摘要:

AbstractSince the beginning of 1963 SIGMA has had a team of operational research scientists working for Compañía de Acero del Pacífico, one of the largest steel-makers in South America. The task has been to demonstrate the value of operational research to the company by solving a series of both tactical and strategic management problems and also to train some of the company's own engineers to form an effective internal operational research team.The company has allowed us to publish the results of any of the studies made and this has made it possible to write a complete story describing not only the work done and the successes, but also the difficulties that were encountered and the mistakes that were made. This article is not intended therefore to demonstrate yet further applications of well-known techniques nor to develop original problem-solving methods; rather it is to come out in the open and reveal the really difficult practical problems that face almost any operational research men and show how we attempted to solve them.

ISSN:0160-5682    

DOI:10.1057/jors.1964.56

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

摘要:

AbstractA generalization of the Discounted Cash Flow method of measuring return on investment is shown to provide a well-defined and useful measure for all cash flow series which can be regarded as relating to an investment project. Problems of multiple solutions and of inadmissible implicit assumptions that can arise with the standard DCF method are thus overcome, while the essential features of the method are retained. In a large proportion of cases met in practice the generalized procedure reduces to the standard one. The possibility of a time-dependent cost of capital is included in the analysis.

ISSN:0160-5682    

DOI:10.1057/jors.1964.57

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

摘要:

AbstractThe derivation of the formula for the economic batch quantity is fairly simple and is often used to illustrate operational research methodology. The model has recently been attacked, on the grounds that a mistaken attempt is made to minimize costs, and that in any case it misrepresents costs. In this paper alternatives are expressed symbolically. It is shown that optimizing any of the alternative functions would be equivalent or inferior to minimizing costs.

ISSN:0160-5682    

DOI:10.1057/jors.1964.58

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

摘要:

AbstractSome of the objections to the classical model used in the theory of batch quantities are reviewed. They fall broadly into four categories (1) the validity of the model; (2) the determination of cost parameters; (3) criteria; (4) implementation. Some of the objections can be met by minor modifications of the model; others are more fundamental in nature. In multi-product situations the classical model can only provide an initial guidance and must be supplemented be other tools.

ISSN:0160-5682    

DOI:10.1057/jors.1964.59

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

摘要:

AbstractThe paper presents a straightforward generalization of the Simplex and the dual method for linear programming to the case of convex quadratic programming. The two algorithms, called the Simplex and the dual method for quadratic programming, are applicable when the matrix of the quadratic part of the objective function, in case this function is to be maximized, is negative definite, negative semi-definite or zero; in the last case the two methods are equivalent to an application of the similar methods for linear programming. The paper gives an exposition of the methods as well as examples and interpretations. The relations with linear programming methods are considered and some starting procedures in case no initial feasible solution is available are presented.

ISSN:0160-5682    

DOI:10.1057/jors.1964.60

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

摘要:

AbstractAn expository account is given of the Dynamic Programming approach to inventory analysis in terms of the problem of the optimal storage policy for repair parts. The demand distribution is assumed to be Poisson or some modification thereof; the delivery time is assumed to be fixed or Gamma distributed while preserving the sequence of the orders. No demand is lost. It is shown that the demand distribution for the delivery period is negative binomial. Formulae are derived for the re-ordering point and the order quantity and these are solved for the geometric demand distribution. An example is calculated which is based on the stocking of repair parts by a can manufacturer in Chicago.

ISSN:0160-5682    

DOI:10.1057/jors.1964.61

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor

ISSN:0160-5682    

DOI:10.1057/jors.1964.62

出版商:Taylor&Francis    

年代:1964

数据来源: Taylor