Optimization of Production Systems

ROGER LEE SALSTROM, PH.D. UNIVERSITY OF CALIFORNIA, BERKELEY, 1989, 119 PP.

CHAIRMAN: J.G. SHANTHIKUMAR

This paper analyzes two specific production problems in order to optimize the performance of a manufacturing system. The first problem concerns determining the optimal bin size and the optimal number of bins for a just-in-time (JIT) manufacturing system. The optimal number of bins and the optimal bin size are determined using a traditional inventory theory approach and using a queuing systems theory approach. Using the traditional inventory theory approach, the lead-time is assumed to be fixed and the optimal values are determined by minimizing the stockout, holding and ordering costs. Using a queuing systems theory approach the optimal values are also determined by minimizing the stockout, holding, and ordering costs. The queuing system model used in this analysis assumes a constant service time or a variable service time, and allows interference from having multiple product lines using a given server. A simulation model is used to determine the accuracy of the analytical results.

The second problem concerns allocating either the workload or the servers to the work centers of a flexible manufacturing system (FMS). Analytical results obtained from the analysis of such systems are used to develop a heuristic algorithm for allocating servers given a specific distribution of workload. The results of the heuristic algorithm are compared to the optimal allocation of servers. In most instances, the heuristic algorithm gives the optimal configuration. (Order Number DA9006494, April 1990.)

Status and Structure of Quality and Reliability Management Systems: Investigation of the Organization and Structure of Reliability and Quality Management Systems in UK and European Industries to Establish Benefits of Such Programs and the Interrelationship between Them

MAHFOUD HAMDOON ABED, PH.D. UNIVERSITY OF BRADFORD (UNITED KINGDOM), 1989, 330 PP. SUPERVISOR: NOT AVAILABLE

The research is primarily concerned with quality assurance and reliability systems in the UK manufacturing industry. The work represents an attempt to establish the status, structure and activities of quality assurance and reliability functions in British and other EEC industries, and to identify similarities and differences existing between them. The study also investigates the relationship between the selected quality assurance system variables and independent variables and tests whether the argument: that a better fit between status, structure and activities leads to a higher financial performance by the organization. An analytical hierarchical model which can be used to describe the quality assurance system is presented. The framework was tested using data

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