ISSN:0160-5682    

DOI:10.1057/jors.1974.69

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

ISSN:0160-5682    

DOI:10.1057/jors.1974.70

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractTwo requirements of professionalism are discussed: consideration of the interests of those not participating in but affected by decision-making in which the professional takes part, and assistance to those who need but cannot afford it. The implications of these requirements to operational research are considered and some illustrations of their fulfilment are provided.

ISSN:0160-5682    

DOI:10.1057/jors.1974.71

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractThis paper deals with a central and recurrent concern of managers responsible for highway tendering: formulating unit bids for Unit Price Proposals. Unit Price Proposals are prepared by the client and indicate contract items and (estimated) quantities deemed necessary to accomplish the proposal objective. The bidder is required to indicate unit prices or bids. These unit bids are multiplied by the indicated quantities and summed to arrive at the bid total. Virtually every tender (bid) is unbalanced in order to improve cash flow. Often the unbalancing is neither competent nor conscious. A linear programming model was devised to determine unit bids that maximize the present worth of future profit. The model characterizes the managerial environment with uncommon competence. Examples illustrate features of implementation. The model is especially useful for large and complicated contracts of long duration. These linear models have the remarkable feature that, for given project information, no other means of unbalancing will yield a greater present worth.

ISSN:0160-5682    

DOI:10.1057/jors.1974.72

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractIn a big organization like the Australian Post Office, where large sums of money are spent to purchase a very large number of items every financial year, the problem is that of allocating the orders of the different items to the competing tenderers at a minimum cost. We have dealt with this in two sections; one is devoted to quantity discounts, the other to order value discounts. We have shown the mathematical formulation using integer and mixed integer linear programming, the mathematical programming systems used, the benefits gained and costs incurred, and the effects of the implementation of minimum cost allocation techniques on the organizational structure of some sections of the A.P.O. We have also shown that these techniques could be used to analyse the relative economic efficiencies of the competing tenderers with the objective of formulating a suitable economic purchasing policy for the organization concerned.

ISSN:0160-5682    

DOI:10.1057/jors.1974.73

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractThis paper describes a computer simulation model which was developed by BP Chemicals International and applied to some of the design problems of a petrochemical complex. The individual plants in this type of complex are closely interlinked in terms of input and output of raw materials, usage from common storage tanks and utilities requirements. Thus decisions taken within a particular area can have serious effects on overall site performance. The simulation model was constructed to assist management in evaluating the consequences of alternative design decisions.The structure and data requirements of the model are described and special mention is made of the decision rules used to arrive at a feasible mass balance. Limitations of the model are discussed and some sample applications are presented, including the problem of the sizing of storage tanks.

ISSN:0160-5682    

DOI:10.1057/jors.1974.74

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractFor the purposes of inventory control and production planning of multi-product lines, often consisting of hundreds or thousands of items differing only in minor ways from each other, it is often found that the variability of demand for individual items can be expressed as a simple function of the expected demand for each item. Usually this is not Poisson variability. In this paper a simple demand model is proposed which generates variability of the type often observed, and which in fact leads directly to the Quadratic Law of Burgin and Wild. It is noted how, in practice, it may be hard to distinguish between this law and the Power Law (Brown). The difference, however, is by no means unimportant, and this is discussed. The statistical problems involved in estimating either law from practical data are also shown to be non-trivial.

ISSN:0160-5682    

DOI:10.1057/jors.1974.75

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractIn effectively applying general exponential smoothing, a central requirement is the use of a proper parameter-a proper rate of discounting past information. Since a single value for the parameter is inefficient under varying demand conditions, several methods to adjust the parameter adaptively have been developed. This paper contains an analysis and comparison of these methods.

ISSN:0160-5682    

DOI:10.1057/jors.1974.76

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractAn algorithm is presented for solving a variant of the transportation problem with a mixture of equality and inequality requirement and availability constraints. The method involves a simple transformation to the solution of a standard transportation problem. Proof is given of the optimality of the solution obtained.

ISSN:0160-5682    

DOI:10.1057/jors.1974.77

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor

摘要:

AbstractA generalization of the standard transportation model in which the origin and destination constraints consist not only of equality but also inequality constraints is considered. It is shown that the model is equivalent to a standard transportation problem having only one additional origin and destination.

ISSN:0160-5682    

DOI:10.1057/jors.1974.78

出版商:Taylor&Francis    

年代:1974

数据来源: Taylor