摘要:

AbstractIn this paper we develop and demonstrate the application of a goal programming model. It is designed to assist top management in incorporating organizational goals when allocating funds to competing projects. Investment decisions, however, normally involve several, often conflicting goals. The fact that some of these goals cannot be measured in dollars or other scales further complicates the problem. Among the many proposed methodologies of multicriteria decision-making (MCDM), goal programming (GP) is perhaps the most popular and widely used. It provides optimal solutions; however, it has a major drawback: the decision-maker must specify the goals and prioritiesa priori. To overcome this problem, we suggest the Delphi method, a systematic procedure to obtain a consensus from a group of participants. It is conducted prior to GP to (1) identify the goals, (2) determine priorities among the goals, and (3) establish a target level for each goal. To test the practicality and extent of applicability, the proposed model is directly applied to evaluate rural road projects of the Division of Transportation, Bureau of Indian Affairs (BIA), US Department of Interior.

ISSN:0160-5682    

DOI:10.1057/jors.1988.139

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractThis paper describes an intelligent decision-support system to help determine optimal mining strategies for W. R. Grace Company, one of the nation's largest suppliers of phosphate-based chemical products. Based on a 0-1 integer programming model which incorporates the knowledge of mining experts, the system helps management assess the mining potential of phosphate rock reserves. The system has been used in making investment decisions valued at over $40 million.

ISSN:0160-5682    

DOI:10.1057/jors.1988.140

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractAnalytical modelling of the work flow through flexible manufacturing systems (FMSs), based on closed queueing network models, has been successfully applied to the early stages of design and analysis of FMSs. This paper describes the advantages of using multiple job-class closed queueing networks for modelling realistic situations occurring in FMSs. The general modelling of FMSs by closed queueing networks is first reviewed. The way Solberg's CAN-Q—a single job-class queueing-based package—deals with several part types is clarified. A new model called MULTIQ, allowing multiple pallet types, each of which is used by several part types, is proposed. Results are derived using the data from an existing FMS. The use of the MULTIQ model for optimization purposes is suggested by some examples.

ISSN:0160-5682    

DOI:10.1057/jors.1988.141

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractThis analysis is concerned with the continuous, deterministic case of an inventory system in which the demand rate of an item is of a polynomial functional form, dependent on the inventory level. Differential and integral calculus are used to find the inventory function with respect to time. From this, the objective function (to maximize average profit per unit time) is developed. For the continuous, multiperiod situation, a non-linear programming algorithm—separable programming—is utilized to determine the optimal order level (the quantity to order up to) and the order point (the quantity at which an order is placed). A numeric example and a sensitivity analysis are also presented.

ISSN:0160-5682    

DOI:10.1057/jors.1988.142

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractMany companies use firm orders-to-date to make forecasts of units to be shipped at a future timetthat isjperiods away,j= 1, 2,...,h. A number of methods for making these forecasts were developed and evaluated using simulation. The time series for bookings was decomposed into a shipment time series and a time series for factors representing the fraction of shipments bookedjperiods ahead. Separate techniques were used for the shipments series (namely, naive, exponential smoothing and Bayesian procedures) and for the factors (naive and exponential smoothing procedures). The accuracy of these approaches, as well as an ARIMA model that ignored orders-to-date, was evaluated by using several simulated patterns of bookings. No approach was dominant, but one of the simplest approaches (naive/smoothing) did comparatively well.

ISSN:0160-5682    

DOI:10.1057/jors.1988.143

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractThe question of allocation of control points in stochastic dynamic-programming models from different areas is considered. A widely used approach is to choose equal time intervals between successive control points. Conditions under which this choice may cease to be optimal are discussed. Two different approaches to statement and solution of a production-control problem are presented.

ISSN:0160-5682    

DOI:10.1057/jors.1988.144

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractSelecting target completion time and appropriate resource availabilities for projects is not easy. In this paper a simple relationship is established to aid the planner in this task. The relationship is based on experiments involving 4942 different network/resource configurations. The relationship can be used to select the best balance between the cost of over-runs and the cost of resources.

ISSN:0160-5682    

DOI:10.1057/jors.1988.145

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractModel identification has traditionally been ignored in forecasting via exponential smoothing. The usual practice is to apply the same model to every time-series in a collection. This paper develops a procedure for model identification in large forecasting applications based on an examination of variances of differences of the time-series. The order of differencing yielding minimum variance suggests an appropriate model for the series. Empirical results show that this procedure selects models that give reasonableex anteforecast accuracy.

ISSN:0160-5682    

DOI:10.1057/jors.1988.146

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractIt may be possible to shorten the overhaul times for expensive machines by forming pools of major assemblies. This paper formulates the problem and shows how to calculate optimum holdings of these assemblies.

ISSN:0160-5682    

DOI:10.1057/jors.1988.147

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor

摘要:

AbstractThis paper presents a heuristic method for solving the uncapacitated facility-location problem (UFLP), which is similar to Erlenkotter's‘dual ascent’procedure. The heuristic is of the‘add’type, which progressively selects facilities to open according to a certain criterion derived from the analysis of the linear programming dual. Computational experience with both (static) UFLPs and dynamic UFLPs reveals that the heuristic method yields solutions in most cases superior in quality to those achieved by the dual-ascent procedure, with barely noticeable additional computation time.

ISSN:0160-5682    

DOI:10.1057/jors.1988.148

出版商:Taylor&Francis    

年代:1988

数据来源: Taylor