In order to estimate an appropriate shop time, the characteristics of waiting time must be revealed, and we have disclosed several estimation formulae. Using those formulae, we can estimate shop times easily, but there remains an important problem; that is, even if the average waiting time is reasonable or fairly short, there cartainly are some jobs with much longer waiting time. So, it is proposed to control the work load of the first stage of the process lest such a job should be created. In other words, newly arrived job should be rejected in the event that the work load, by accepting it, will exceed the limited value given. This control system is considered to be so-called finite queuing system, but we have investigated the characteristics by a convolutional numerical analysis.

View full abstract

Some contributions of the pattern recognition methodology to design of sampling plans are described and illustrated with no prior information about the quality of lots. Specifically speaking, the modified Min-Max and Neyman-Pearson diagonosis rules are presented for design of single sampling inspection by asttributes. The recommended procedures enable us to find the following two plans. The first insures the specified consumer's risk, minimizes the maximum of the average loss due to misclassification and reduces the sampling cost. The second minimizes the sum of the agerage loss and sampling cost and insures the consumer's risk.

View full abstract

The previous reports of this research discussed on "optimum selection of the localized parts" one of the two basic problems being faced by firms operating under the regulations by Local Manufacturing Programs. This paper examines firstly the other basic problem, "determination of the optimum product mix" and then the combination of the two problems. A three-step algolism is proposed for the latter, although the former is formulated as an orbinary integer linear programming problem.

View full abstract

This paper discusses a design of production system for the agricultural product processing industry where the raw materials are mostly supplied seasonally. As the raw materials have a limited shelf because of their liability to decay, it is necessary to design the production system whereby they are processed smoothly in the harvest. We analyze the structual relatilnship between the manpower as the determinant of production capacity and the process capacity of the final and intermediate products under a given supply pattern of raw materials. The result may be useful to specify manpowers and process capacity.

View full abstract

Use of a probability paper to analyze breaking data of materials easily is preferable which are doubly distributed exponentially. Graphical plotting, however, is not strictly applicable to the censored samples without modification. This paper is concerned with the determination of plotting positions on probability paper based on minimum variance linear unbiased estimator. A plotting technique by use of the optimum spacing method is also proposed for large samples.

View full abstract

There exists a trads-off relationship between profitability and safety associated with a capital investment plan. This paper proposes a method of measuring the risk of "Insolvency", to represent the degree of safety and examines the conditions on which the profitability and safety are simultaneously satisfied under conditions of risk. The role played by the reserved funds in order to reduce the risk of insolvency is also examined. In conclusion, the sensitivity of the variables considered upon the profitability under the penalty of insolvency is presented.

View full abstract

In certain cases, no methods are available to measure how much the efficiency of a production system is affected by such factors as lot-size, product groups accompanying changes of job-size, processing time, etc. A new measure, named Flow Difficulty Coefficient (FDC), is proposed which proved useful. FDC is based on the concept : how rapid a given load is passed through the system in the actual case against the case of no constraints regarding operation sequences, set-up time, etc.

View full abstract

An efficient scheduling system for jobshop type production by use of mini-computer is developed which faclitates the processing of changes in schedules originated from the specification changes, etc. The cases in two enterprises are mainly treated in this paper.

View full abstract