摘要:

This paper develops a decision rule to enable an a priori classification of a production system that should utilize a JIT- or WIP-type inventory control policy. A two-station deterministic serial production system is analysed. A parameter a— the ratio between WIP and maximum shortage—is defined, and a cost function K — f( α) is modelled. It is shown that α*—an optimum value of α—is a characteristic parameter of the system, can be evaluated a priori based on known parameters, and can serve to identify a production system as JIT type or WIP type. The concept of an OC curve of a system is introduced and it is concluded that JIT is not always favourable over WIP.

ISSN:0020-7543    

DOI:10.1080/00207548908942597

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

This paper presents a vehicle system simulator, AGVSim2, to be used in the evaluation of control strategies of real-time free-ranging vehicle supervisory controllers. The C-based discrete-event simulator is designed to be flexible so that many system configurations can be modelled. Also, the simulator allows for complex free-ranging vehicle manoeuvres, bidirectional flow, multiple vehicle types, and multiple loads on a vehicle. Instead of modelling the vehicle controller logic, the simulator is linked directly to the vehicle supervisory controller software. The simulator reports a variety of performance statistics and a trace of the system activities so that the performance of the supervisory controller can be evaluated. To improve the evaluation procedure, the simulator is also designed to be linked to an animation module that graphically displays the vehicle movements.

ISSN:0020-7543    

DOI:10.1080/00207548908942598

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

A microcomputer-based, Turbo Prolog expert system for selection of industrial trucks is described. Details of the industrial truck information supporting the development of the expert system are provided. The structuring of this information into a usable knowledge base and design of the inference mechanism to specifically address the truck selection problem are overviewed. Implementation details are discussed and the use of various AI concepts as applied within the expert system is described. Advantages and limitations of the expert system are suggested.

ISSN:0020-7543    

DOI:10.1080/00207548908942599

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

We consider a flexible manufacturing system consisting of one unlimited central buffer and n workstations each having a limited local buffer. The in-process inventory is centralized through the central buffer. General independent random processing times are assumed at each station. The system is reviewed periodically. We address the routeing control problem, where the routeings of jobs from the central buffer to each station are to be determined periodically to minimize the in-process inventory costs. A dynamic programming model is developed for the determination of the optimal routeings. The computational formulae are derived, and a solution approach is established. The computational results for a real flexible manufacturing system are reported.

ISSN:0020-7543    

DOI:10.1080/00207548908942600

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The use of tubular cathodes considerably widens the technological possibilities in ECM of large-size components, especially if the allowance (area to be machined) is removed in solid form.

ISSN:0020-7543    

DOI:10.1080/00207548908942601

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The research on lot sizing is extensive; however, no author in the literature reviewed to date provides an optimal solution algorithm to a prevalent problem which is found in manufacturing. A multi-level, general product-structure, variable-cost model is presented which follows the procedure of a closed-loop material requirements planning (MRP) system, and incorporates many conditions that production and material managers find in practice. A branch and bound (B&B7) algorithm is developed. The efficiency of B&B is derived from effective lower bounds and solution procedures which are determined on the basis of the space-time structure of the MRP lot-sizing problem and its non-convex total-cost function. This path-dependent lower bound is computationally efficient and guarantees an optimal solution. The B&B algorithm is tested on problems and compared to heuristics in the literature.

ISSN:0020-7543    

DOI:10.1080/00207548908942602

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The objective of this research is the development of an optimization procedure to aid a warehouse planner in the design of selected three-dimensional, palletized storage systems. All alternatives are compared in the overall model while simultaneously considered the following factors: control procedures, handling equipment movement in an aisle, storage rules, alternative handling equipment, input and output patterns for product flow, storage rack structure, component costs and the economics of each storage system. The resultant model is more complete than any other currently available for use by a designer in this complex decision environment.

ISSN:0020-7543    

DOI:10.1080/00207548908942603

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

This paper presents a dynamic programming (DP) algorithm for solving an assembly line-balancing )ALB( problem with parallel workstations. Solutions represent a trade-off between the minimum number of stations required to achieve a balance and the cost of installing additional facilities. Both task costs and equipment costs are considered. A second feature of the algorithm is that it takes into account unproductive time during a cycle.

ISSN:0020-7543    

DOI:10.1080/00207548908942604

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The loading problem in a flexible manufacturing system (FMS) is viewed as selecting a subset of jobs from the job pool and allocating jobs among machines. A two-stage branch and backtrack procedure is developed with the objective of maximizing the assigned workload. Heuristic procedures are also developed with a bicriterion objective of minimizing the workload imbalance and maximizing the throughput for critical resources such as the number of tool slots on machines and the number of working hours in a scheduling period. The case of machine-dependent processing times is also dealt with. An illustrative numerical example accompanies each procedure.

ISSN:0020-7543    

DOI:10.1080/00207548908942605

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Block-diagonalization of the machine-component incidence matrix is the first step in the implementation of group technology. Even powerful algorithms will fail to achieve this if the matrix itself is not amenable to block-diagonalization. The present work analyses the properties of the matrix and identifies the standard deviation of the pairwise similarities (Jaccard7rpar; of the vectors as the major factor that decides the groupability of the data set. Many data sets ranging from the perfectly groupable to the most ill structured ones are analysed and presented. The groupability curves show the variation of the property against the relevant factors.

ISSN:0020-7543    

DOI:10.1080/00207548908942606

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor