The present paper proposes a methodology for maximizing the effect of module inventories, which are allocated at multiple points in manufacturing processes, for the estimation of earlier due dates in make-to-order production. In this research, modules are defined as semi-finished products or processed parts that can be used for producing plural final products or higher-level semi-finished products with the intention of increasing operational efficiency. The use of modules allows manufacturing costs to be reduced in the present industrial environment of product diversification and helps to secure customer orders through estimating earlier due dates. However, the strategy of holding module inventories is accompanied by the burden of incurring unnecessary inventory investment, inventory carrying cost and obsolescence cost. Therefore, the strategy must be applied by a method that minimizes such performance measures regarding the module inventories, considering trends in customer demand and the comprehensive product structure, which is defined as a network of plural product structures. Specifically, the positions and levels of module inventories in the given comprehensive product structure are optimized using a genetic algorithm. All final products, semi-finished products and processed parts including modules are produced based on customer orders. However, modules can be produced based on the manufacturing orders released according to a make-to-stock production strategy when the required facilities are not busy. This situation sometimes occurs because customer demand is generally volatile. The module inventories are controlled by the Max-Min reordering policy, where Max is the only parameter if Min can be set equal to Max. In the present paper, the values of parameter Max, which control the module inventory levels, are optimized. Two measures of production performance are considered. One is the average lead time for all customer orders, and the other is the total inventory investment required for holding modules in a comprehensive product structure. The computation results were obtained through performing a number of simulation runs using a due-date estimation algorithm in a framework of multiple-objective optimization. As a result, it was proven that the Pareto-optimal solutions, which involved information on the optimal allocation of module inventories under the given customer demand patterns and inventory investment coefficients assigned to modules, could be successfully found.

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This study focuses on controlled respiratory data gathered when heart rate variability (HRV) is measured to assess the mental workload (MWL) of a task. The respiratory data has been narrowly analyzed to confirm the control of respiration. This study proposes a new index for evaluating the MWL caused by the consumption of working memory resources for a task by using controlled respiratory data. This study examines the effectiveness of the index through the experiment. The ratio of the pre-stimulus respiration to all respiration under controlled respiration in accordance with the stimulus, which represents the average interval the subject breathed during a calm state, is proposed as the new index for evaluating MWL. In the experiment, 12 subjects were required to do two tasks, for which the consumption of working memory resources was expected to be different. While doing each task, they were also required to simultaneously breathe in accordance with the stimulus which represented the average interval the subject breathed during a calm state. The results of the experiment revealed that the ratio of the pre-stimulus respiration could reflect the existence of MWL for the task. The results also revealed that the ratio could reflect the difference in MWL caused by the consumption of working memory resources between the tasks. From these results, the effectiveness of the ratio of the pre-stimulus respiration as the index for evaluating MWL is suggested.

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Process capability indices are widely used to provide evaluation measures of process potential and performance. Especially, the process capability index C_<pm>, which is defined by the tolerance and deviation from the target, is called the Taguchi index. Boyles investigated the statistical characteristics of the C_<pm>, estimator, and also proposed a methodology for the C_<pm> control chart. Needless to say, since the process capability index C_<pm> is based on the concept of the quality loss introduced by Taguchi, it basically relates to the concept of cost performance. In this article, we consider the economical operation of the C_<pm> control chart in conformity with the expected total operation cost function based on the sampling cost, the sample cost and the surplus loss by means of ignoring the out-of-control state. Then, the economical operation of the C_<pm> control chart minimizing the total operation cost is investigated.

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The purposes of this study are to grasp the satisfaction and the feeling of well-being of elderly people who use daycare services, and to develop countermeasures which make care services, as a social resource in our community, meet the needs of elderly people who need care. An inventory survey was carried out about the satisfaction and the feeling of well-being of 59 users of daycare services provided by a certain geriatric health services facility. The results are as follows: (1) Most users held a high feeling of satisfaction about services offered, and they were very satisfied regarding bathing care in particular. There were differences in the amount of satisfaction between male and female users for some services. Especially, female users showed a high score in communication activities. (2) The feeling of well-being for the care service was influenced by difference in gender, and human relations with other users, and high scores were recorded for female users and users who were satisfied with human relations. According to the results, it is necessary that care services must be provided carefully by considering differences in gender and human relations with the other users in order to meet the needs of elderly people who need care.

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Recently, the use of affiliate sites is recognized as a way of Internet business without incurring a huge initial cost. However, there is a problem that half of the persons who are managing the affiliate sites can be earning less than 1,000yen a month. Because this problem obstructs the development of a continuous affiliate business, it should be overcome. If the knowledge of excellent managers who are earning high profits can be used and a highly efficient way is clarified, then it will be helpful to affiliate sites operated by novices. Many interview comments and suggestions by excellent managers can be found in journals. However, an affiliate site novice cannot make use of the knowledge of excellent affiliate site managers unless it is systematic and well known. In this paper, new methods to analyze the knowledge of excellent affiliate managers and features of excellent affiliate sites are proposed. The first proposal is a technique to construct a system structure based on the techniques of excellent affiliate managers, taken from the interviews printed in journals. The system constructed here shows a list of important key points and is a systematical representation of the knowledge of excellent affiliate site managers. The second proposal is a method to clarify the features of an individual affiliate site. To do this, the items to be checked items are listed. The methodology of a useful analysis to construct and manage affiliate sites is established applying these two viewpoints. Additionally, the effectiveness of the technique proposed in this paper is clarified by applying of our proposal to a set of excellent affiliate sites.

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In large-scale integrated circuit (LSI) manufacturing, rapid yield improvement continues to be a significant subject when attempting to reduce manufacturing costs. In yield improvement activities, it is crucial to assign resources to yield loss factors according to the significance of impact. To support these activities, a new decomposition method for the yield loss factor is introduced in this paper. The method decomposes yield loss into different factors caused by defects such as particles and scratches for each process step. To verify the accuracy of the decomposition method and the reliability of the yield loss factors, Monte Carlo simulation is applied.

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Virtual reality (VR)-based assembly training aims to respond to time-based competition. In this study, the effects of virtual reality on assembly training are examined. In this assembly training, workers first memorize work procedures and checkpoints to guarantee quality. Assembly procedures and checkpoints for guaranteeing quality are shown on a screen in three-dimensional animation. This training is continued until the worker memorizes all assembly procedures and check points. Next, the worker can experience the assembly work in virtual space by grasping parts that are located on parts shelves. The worker can grasp the parts by wearing a data glove. A screen of the training system is inclined 45 degrees. By inclining the screen, parts shelves appear when the worker looks forward, and the upper surface of the worktable can be seen when worker looks downward. To verify the effectiveness of proposed method, workers train using an electrical appliance that has a small number of parts and an electronic device that has a large number of parts. Workers train using the VR system or a work procedure paper about each product.

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Recent larger and more complicated products involve a great deal of engineering design processes where many iterations among various engineering tasks are often observed. The Dependency Structured Matrix is very useful for identifying where iterations take place, and the pair-wise comparison matrix (PCM) can show which portions of the design problems require much time during the iteration process. This paper discusses iteration models used in engineering design processes and attempts to predict the convergence of iterations within a design project and design problems' features using a PCM. This model is applied to a semiconductor project for the development process of the networking processors to illustrate the model's utility in describing the primary features of an actual design process. The findings are confirmed by eigenvalues and eigenvectors computed using a PCM, which enabled the identification of two dominant features and related tasks weighted with elements in eigenvectors. The impact for cost and scheduling over the actual design process can be found as the result of the dominant features, which include iteration in between logic design and its verification, and also in between physical implementation and its verification. Two models built with replaced tasks are simulated, and the results are found to be improved. Semiconductor hardware IP (intellectual property) replaced based on this method has been confirmed to have an improved impact over the actual design process. The managerial practice and theory are discussed, and suggestions for further research are provided.

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A time series study conducted as part of this research confirms a relationship between psychological aspects and teamwork. This research initially hypothesizes the relationship between company achievement and teamwork awareness during organizational restructuring. The company produces and sells machine tools. It is clear that improving employee teamwork awareness increases sales and profits. Individual awareness generates team awareness, which in turn, leads to greater organizational achievement. However, this kind of research from the psychological side has been minimal. The survey was done twice. First in August 2004, and then again two years later in July 2006. From the results, the following hypothesis was accepted: "Identification of teamwork awareness become stronger according to the time series." In conclusion, this research confirms that increased teamwork awareness of the employees leads to positive activation, a higher sales volume and more efficient inventory management. This paper certifies that team competency as teamwork awareness leads to positive achievement.

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In recent years the number of M & As has increased in Japan. A Take-Over Bid (TOB) is one method employed to purchase a listed company. Various studies have been undertaken to elucidate the conditions under which a TOB will succeed. However, no study has reported what kind of strategy is needed so that a TOB has meaning as an investment. We have already shown that we can find an appropriate strategy by assuming an action model of a stockholder in a TOB. In this report, we aimed to applying our approach to real TOB data. We derive a stockholder action model from real data and show how to arrive at optimum buying prices by considering the effect of synergy after a M & A. As a result of this study, we obtained results showing that a TOB carried out for the acquisition of a majority interest does not always achieve the maximization of corporate value. Not so many shares are needed when the effect of the resulting synergy will be small. The optimum premium differs according to the characteristics of the stockholder action model.

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