This paper deals with a heuristic scheduling method for combinatorial 'lot size and lot sequence' scheduling problem under the divided-delivery condition. This method gives us an approximate schedule with minimum flow time. This method produces many small size scheduling problems under the same divided-delivery condition as a real large size problem. And this method saves some characters of optimal schedules produced by Branch & Bound Method about these small size problems. Then, this method approaches a real large sim problem making use of these characters. In this paper, we show the algorism and the performance of this method.

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This paper treats two problems I and II on acceptance sampling. Problem I is the design problem of single variables sampling plans of the "point-of-control" type based on doubly exponential distribution with known standard deviation. Problem II is the conversion problem between parameters of two sampling systems, viz., the system of the "point-of-control" type and that of the familiar "two-point specified" type. These two problems are solved by two kinds of solutions A and B, respectively. Solution A is the solution which is based on the sample mean. On the other hand, Solution B is the solution which is based upon an efficient estimator (MVLUE) for mode (location parameter) of the distribution and is making use of c.d.f. of the standardized Pearson's Type III distribution that can approximately represent the OC function of sampling plan in question, The theoretical background of each solution is discussed at some length and its practical procedures are illustrated by an example respectively. Finally, Solution A is compared with Solution B from the various points of view.

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Recently, banks need to manage not only profit, but also interest rate risk, liquidity risk, and so on. Therefore risk management becomes very important. In this paper, we propose a multi-currency ALM (Asset Liability Management) model. It is an advanced multi-period model proposed by the authors. The feature of this model is that it can show the trade-off relation between profit and risk. and the mathematical model can be solved with goal programming in order to treat this relation. As a result, numerical examples show the usefulness of the model.

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The main subject of this study is the structuring of a technique for in-facility layout on the premise of polyhedral layout factors. The report Taniguchi outlines the procedure by which the weighting values of each layout factor are considered to the extent possible and how coordinate plots are extracted by regarding the planning policy as a set of weighting value of each layout factor. In this report, we describe a means of evaluating how to retain this positional relationship in the initial coordinate plots when the volume and shape are incorporated into each plot(point) in the spatial layout planning. One method of solving this evaluation problem, in which the rank correlation coefficient representing the consistency of distribution conditions for the weighting values before and after layout is used as evaluation criteria, was proposed in Taniguchi. However, included in these studies were cases where the evaluation results were severely affected by the data scale conversion process. This report aims to clarify this matter and set up a more complete evaluation process incorporating a new solution method.

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For the economic evaluation of investment projects, it is necessary to estimate the economic life of the equipment accurately. However, the previous studies of this problem haven't dealt explicitly with the effect of the cash outflow relating to taxes. In the economic evaluation, the corporate income taxes and municipal property tax must be considered. The object of this paper is to construct the after-taxes economic life model with the like-for-like replacement. We can get the findings that, for the estimation of the economic life, it isn't absolutely necessary to consider the cash outflow relating to taxes, when capital cost isn't high. But we leave taxes out of consideration, we may make the accept/reject decision wrong.

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The purpose of this study is to detect an influence of the N factor (i.e., the neurotic personality trait) on the stress in the workplace. The number of the subjects are 306 graduated female employees. This research is on stressor and stress in the workplace and on an influence of the N factor. The stress dealt with in this research is the feeling of distress. The N factor is measured by using the N (neuroticism) scale of MPI test. The results are as follows; (1) The N factor increased the growth of the stressor, (2) The N factor directly influenced stress and increased its strength, and (3) The effect of the interaction of the N factor and the stressor to stress was significant.

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This paper presents two economic order quantity models in which a fraction β(t) of the demand is backordered and the remaining fraction 1-β(t) is lost during the stockout period. Under the assumptions of deterministic demand rate and deterministic lead time, an objective function representing the annual cost of an inventory system by defining an ordering cost, an inventory holding cost, a time-weighted backorder cost and a lost sales penalty cost is developed. Model A suggests an annual inventory cost function defined by introducing the function of backorder ratio that is linearly decreasing in proportion to the length of backorder period. In model B, the annual inventory cost function is defined with the assumption that backorder ratio, β(t), follows the negative exponential function. Both proposed models provide numerical iteration methods to obtain the economic order quantity, respectively. In case β(t)=1,the presented both models reduce to the backorder model, respectively.

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We model the generic structure of production control system for multistage manufacturing environments and introduce a hybrid push/pull production ordering rule operated periodically, which combines the benefits both of push and pull-type ordering concepts. The transmission of demand information plays an important role in multistage production control system. Using the structure of multistage processes, it has been clear that the proposed multistage production strategies have a nested structure of a single-stage. Assuming a specific demand and forecasting model, the variances of inventory level and production level at each of multiple stages are investigated to provide insights into achieving just-in-time deliveries in multistage manufacturing environments.

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Suppose there are several machines of different performances and several jobs to be processed. Though each job can be processed by a given machine, the processing time depends on the machine used. Also suppose that there is no precedence relation among jobs, Then, the problem which assigns each job to each machine so that the makespan can be minimized is called the unrelated parallel-machine scheduling problem. This study proposes an optimization algorithm of the problem based on the branch and bound method. First, the problem is formulated as a mixed 0-1 integer programming problem (P) to confirm several properties related to the problem (P). Next, a simple algorithm to determine the lower bound of (P) is presented on the basis of the properties. Finally, a branch and bound method to solve the problem (P) is constructed, and its effectiveness is discussed through computational experiments.

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This paper describes the input device using recognition of pointing motion with the index finger by image processing technique. The pointing motion is made clear from the state (bend or stretch) of the index finger as follows. Firstly the hand shape is measured at a 0.1-second interval by two CCD cameras which are set up at the side and the top. Secondly the positions of forearm center, the index fingertip, and the index metacarpophalangeal joint are calculated from the contour feature that is extracted from each hand image. Finally the pointing direction is estimated from two regression lines which are calculated from the contour feature data between the index fingertip and the index metacarpophalangeal joint.

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