Plant Layout has been developing through research, experience and practice for many years. This paper intends to give a general view of the present status of the study on Plant Layout, and also to indicate some points to serve future growth of the study in this area. I would like, at the start, to give a brief account about my position, followed by more detailed description of the above subject.

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In the field of industrial management, many of the data collected are sometimes of categorical or qualitative nature. But there is a tendency in analyzing such data composed of nominal or ordinal variables being to igonore their discrete characters and to proceed with continuous variale method as Fisher's linear discriminant function. This paper is concerned with the problem of classifying items which belong to one of two classes. Each classifying item is characterized by a discrete variable which has the multinomial distribution. We present a sample-based method for the two group multinomial classification and some brief comparison of this method to the other such as the use of linear discriminant function, distance method and so on. A procedure for the selection of subset of variables for the two group classification problem is also described.

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This paper presents an approximation method, called "Space Method" for convenience' sake, to the integer-programming problems with 0-1 variables. The basic idea of this method is that, for each prokect, we make a scalar value as a sort of spacial volume by multiplying the amount used of limited resources. Then an index of profitability is assigned to each candidate project in the same way as the Effective Gradient Method (EGM). Two experiments are designed to investigate the properties of our method. In comparison with the primal EGM, our method is partially superior. However, the important finding is that these two approximation methods are mutually complemented.

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This paper is concerned with the problem of maximum likelihood estimation of the location and scale parameters in the doubly exponential distribution from multi-censored samples. The estimation procedure performed here gives : (1) formulae of caluculating maximum likelihood estimators for the location and scale parameters from multi-censored samples, (2) asymptotic variance-covariance matrix of ML-estimators, and (3) method of determining the confidence region for location and scale parameters by the likelihood ratio test theory. A numerical example using CFRP fatigue test data illustrates the proposed method in the case where it is applied to multi-censored samples.

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An adaptive forecasting is proposed to improve the adaptability to the non-stationary variation of the time series data. The distribution of weighted sum of square error approximated by Gamma distribution gives the criterion to obtain the confidence intervals of the variance of the forecasting error. Thus the new testing method which utilizes the above confidence intervals to change the parameter values of the model is established in this paper. Both theoretical and numerical analysis by simulation data and sales data show the superiority of the new adaptive method to the prevailing ones.

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Most studies on agglomeration economy have ben qualitative, and no attention seems to have been focused on mathematical analysis. This paper is an attempt to present a rationale, explaining why agglomeration economy can arise, as a result of clustering of people in space. The method bases on probability theory and the study pays attention to the coefficient of variation in the Poisson distribution. In addition, the mathematical rationale in this paper is much supported by the empirical evidences of hospital, retail and industry locations, as the illustrative cases.

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An analysis for the maximum total profit was performed in an attempt to determine optimal parts to be machined in a limited time available for the given machine tool by applying Group Technology concepts. In addition, the optimal machining speeds to be utilized in manufacturing the selected parts were determined. A computational algorithm was developed for this optimal product-mix decision as well as for determining the optimal machinign speeds, and a numerical example was shown.

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This paper, continued from our previous paper, deductively established 18 recommendations for "autonomous work group system" based on the three principles; respect for humanity, demopcratic management, and small group activities. We confirmed the propriety of the recommendations by interviewing the persons in charge of promoting the group activities at ten corporations. As a result, we affirmed the properiety of all the recommendations excepting the following four; democratic election of group leaders, evaluation system for work group, simplification for the management of workshops, and training in workshops for job rotation. The above four recommendations were demonstrated by us. It was shown that the autonomous work group system now spreading in our country indicated a possibility of increasing sense of "subcontract of management" on the part of operators.

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The objective of this paper is to improve the transient response of the exponential smoothing with additive trend and periodical terms. A new exponential smoothing is derived from exponentially weighted least squares error criterion. Smoothing constants and variances of forecast errors are calculated numerically in the case that a trend is linear and a period is twelve. This method offers an advantage of having no tenency to oscillate for long periods with overshoot and undershoot in transient responses.

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On a two-unit priority standby redundant system is discussed on the preventive maintenance which maintains the system reliability. We also consider that a subunit (not priority unit) has the failure time distribution. Markov Renewal Process is a very useful theory in the analysis of system reliability. Finally, we derived the Laplace-Stieltjes transform of the distribution of the time to the first system failure (TFSF) and the mean time to first failure (MTTFF).

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