In this research, we propose a conceptual model for understanding customer needs, which considers the nature of the benefits and costs associated with the usage of a product or service. Customer needs are divided into substantive needs, which are the fundamental benefits sought by the customer, and contingent needs, which arise due to usage costs imposed by the product or service. Based on their interrelationship, we propose the following categorization of product or service elements : benefit, compensatory, facilitating, indifferent, and usage cost elements. The model's validity is shown through a survey of consumer perceptions of usage benefits and costs in several service industries. Furthermore, its superiority in explaining consumer preferences is demonstrated through a conjoint analysis of survey data on waiting time. The model's relevance to manufactured goods and implications for quality planning and design is also discussed.

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This paper deals with the method for due date assignment in case of various work loading, i.e., the allocation of production requirements against available capacity, and how the due date are determined in sequencing the job shop to attempt to satisfy the due dates. First, this paper investigates into the effect of shop load levels on due date assignment and presents total penalty cost of earliness and tardiness as a new performance measure at various priority rules. This criterion is useful when the objective function of the company includes the penalty per unit of time if job completion is delayed beyond a specified due date. The shop studied consisted of five machines, the number of operations per job being equal to the number of machines. Then, the output report was analyzed by means of computer simulations, and a set of 10,000 jobs were used for all of the test reported here.

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A production manager of a job shop will use the results of scheduling in several aspects of decision making and study what procedure should be used in sequencing the jobs to attempt to satisfy the due date. This study has clarified that if the due dates are assigned to the jobs, the due-date rule is better than the slack rule in the dispatching rule. The complex rule is proposed based on the due-date rule. When the shop loads are heavy, this complex rule is especially effective. The shop studied consisted of five machines, the number of operations per job being equal to the number of machines. Then, the output report was analyzed by means of computer simulations, and a set of 10,000 jobs were used for all of the test reported.

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Recently, Arizono proposed an entropy model in order to analyze consumer's brand selection behavior for goods with some attributes. By using this model, we can estimate the market shares. In this paper, we assume that there are the categories of consumers having preference for one brand exclusively, or for some brands. Then, we attempt to extend Arizono's entropy model to the model in order to estimate not only the market shares but also the probabilities of these categories. A method of estimating the relative weights between attributes based on the extended entropy model is also discussed.

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We consider an optimal lot size determination problem for a multi-item multi-level production inventory system under the assumptions that demand of each final product is deterministic and stationary and each processing is instantaneous. The objective is to determine a lot size for each item so that the system may satisfy final product demands and minimize the sum of inventory holding costs and fixed charges for processing per unit time under the constraint of time-invariant lot size. In our approach, taking the line other than the concept of 'echelon inventory' originally suggested by Clark and Scarf, we use directly the installation inventory for computing inventory holding cost. The purpose of this paper is to propose a new approach to obtaining near-optimal lot sizes in the system by use of the 'reciprocal function' solved by Muramatsu.

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Since jobshop scheduling problems are NP-complete, efficient and effective heuristic methods should be developed for obtaining near-optimal schedules to large-sized problems."Complex Random Sample Scheduling(CRSS)" proposed in the previous papers works well for solving any permutation scheduling problems. This paper improves the method to solve any intractable jobshop scheduling problems. Examining the extended CRSS by applying it to the well-known three benchmark N/M/J/C_max problems presented by Muth & Thompson made it clear that the proposed method efficiently gives a near-optimal schedule with high accuracy.

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This paper deals with a production scheduling problem in the two-stage hybrid flow shop, where there is one machine at the first stage and J kinds of different machines at the second stage. At the first stage, Basic cyclic scheduling and Irregular cyclic scheduling are used as alternatives for production batch scheduling. The former scheduling includes one production run for each family in one cyclic flow. The latter scheduling includes the different number of production run for each family in one cyclic flow. This paper compares which scheduling system is superior in makespan, by analyzing how the length of production run will affect the manufacturing performance in various of work-load imbalance levels.

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Recently, many companies have accomplished high efficiency "stockless" manufacturing as a result of adopting "JIT" production system. Moreover, as the individual preference has become strong, the variation of products should be developed rapidly. Therefore, in manufacturing is often processed only 1 unit per 1 month. Suppose that KANBAN is applied to such rarely withdrawal parts, the quantities of WIP become larger in the factory. MRP/JIT method, an integrated concept of MRP and KANBAN, is proposed to solve problems caused by rarely withdrawal parts in KANBAN production system. The proposed MRP/JIT system, the improved fixed interval withdrawal KANBAN system are compared mutually under variety conditions like processed rate of parts and analyzed total operation cost. Furthermore, the efficiency of the above-mentioned methods is investigated.

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This research investigates the impact of two order-release strategies that decide the release timing in job shop environments over a range of work flow conditions. Two symmetrical and typical order-release strategies are Studied in this research. One is a pull-type strategy that recognizes the job shop as a full work system, such as the just-in-time system. The other is a push type strategy based on the Input/Output control, such as the MRP system. First, we explore the work-in-process level necessary to maintain a certain machine utilization level at each flow rate proposed in this research, which characterizes the flow of work in the shop. Then, we compare these two order release strategies, taking job flow time as manufacturing performance, under the same utilization level.

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A cellular manufacturing system, which consists of machine groups and parts families, is one of methods to cope with multi-product small sized production. In this paper, a heuristic procedure is presented for manufacturing cell formation considering operation sequence of parts. Manufacturing formation methods proposed before, usually, minimize intercell parts movements or product of the part movements and intercell distance. But the intercell distance is determined by cell layout. Also, a decrease of intercell part movements lead to an increase of intracell part movements. So, a single-line layout is assumed to estimate the part movements. Then, machine groups are determined to minimize the total movements of the parts, and part families are assigned to the appropriate machine groups.

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The purpose of this study is to build an inventory model to take into account both of backorder and lost sales during stockout period for the case of single echelon, single item, stochastic lead time and deterministic demand. A procedure to reach the minimum expected annual inventory cost is suggested. The backorder rate is defined as a dependent function of backorder period in the model. The suggested model is reduced to the backorder or the lost sales model if cumulative backorder ratio is 1 or 0,respectively.

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This paper deals with a heuristic decision method of multi-stage lot scheduling policies in the present situations where optimal schedules or good approximate schedules can easily obtained by fast computers and many effective scheduling algorithms. This method researches into the characters of three scheduling methods for a single-stage lot production process. They are optimal scheduling method, combination scheduling method of cyclic schedule and backward schedule, and new scheduling method for stabilization of all products' demand intervals. Then this method searches for a multi-stage scheduling policy to use the optimal single-stage scheduling method more effectively, making use of Branch & Bound method with the above mentioned characters. And we show the procedures of this method through some numerical executions.

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The purpose of this study was to compare the degrees of influence that each of the 5 psychological factors of vocational choice had on one's desired occupation. Subjects were 194 3rd-year male undergraduates : 85 of them hoped to become industrial engineers and 109 hoped to become teachers. The study investigated views about life and vocation, vocational abilities, vocational interests, and characters. The following were the main results : 1) Concerning vocational abilities, those who hoped to become teachers were recognized to have higher abilities than those who hoped to become industrial engineers in three field : exercise, problem solving, and mathematics. 2) Concerning vocational interests, those who hoped to become industrial engineers showed Holland's realistic type, while those who hoped to become teachers did Holland's social type. 3) Concerning their characters, those who hoped to become teachers proved to have such characteristics as cooperativeness, thinking introversion, low rhathymia. The opposite ones were found in those who hoped to become industrial engineers. 4) The psychological factors of vocational choice to give a large influence on one's desired occupation were vocational interests, characters, vocational abilities.

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In order to effectively implement the setup operations on a pallet, machining workers have to suitably install workpieces to be machined on a pallet, while considering the sequence of machining operations. Skilled workers can easily implement the setup operations ; however, it is very difficult for unskilled workers. In this paper, first, the method for determining the optimum sequence of operations as well as the optimum allocation of workpiece on a pallet is proposed. Then, the computer aided instruction system which is the training and evaluation system for skillfully implementing the setup operations on a pallet is developed to approach the calculated optimum solutions with a repeat learning of workers. Finally, the training effectiveness of workers by using this system is demonstrated with a numerical example.

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Recently, there are many learning algorithms of layered neural networks. As one of them, Watanabe et al. proposed a back-propagation algorithm via the Extended Kalman Filter. In this algorithm, they make the learning rate time-varying by the Extended Kalman Filter. However, Watanabe et al. could not use this filter enough, because they treated the weights and biases as independent variables. In this paper, we consider the weights and biases connected to the same unit have the mutual correlations, and propose an improved backpropagation algorithm via the Extended Kalman Filter. Then, solving the XOR problem and the parity problems, we compare the ability of our proposed algorithm with that of Watanabe et al.'s one. Furthermore, we apply the proposed learning algorithm to the classification problem of the iris data.

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Influential tactors in the stimulation of group activities in various workshops are discussed. As the behavioral style of QC circle leader, two new dimensions are proposed to the Performance and Maintenance style distinguished in the PM theory. The effectiveness of S-style in self discipline and of T-style in the teaching of knowledge and technology are verified. In the questionnaires distributed to six manufacturers emerge 166 effective responses. The effects of 4 dimensions of leadership behavior on small group activity are analyzed with regard to group cohesiveness, group norm, cohesiveness×norm, autonomy, relations with office organization, and group performance. The mediation variables are composed of nine indices of circumstantial characteristics and six types of leaders' temperament.

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This paper considers a single machine scheduling problem under the constraints of ready and due times which have been specified. This problem takes account of the supplies of materials or parts in just-in-time production environment. An optimization algorithm using restrictive conditions on branching is developed to solve the scheduling problem, based on the Branch-and-Bound (B & B) method so as to minimize the total earliness. By using restrictive conditions, the B & B tree will be effectively pruned and the efficiency of search and computation will be enhanced. The effectiveness of proposed algorithm is also shown by simulation results.

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When plural parts are processed with a numerical controlled complex machine, there arises a problem of selecting tools that are to be mounted on the tool magazine to minimize the number of tool exchanges. It has already been shown that this problem can be formulated as the set covering problem (P) by enumerating tool sets mountable on the tool magazine ; i. e., tool modules. Listing all tool modules, however, is not practicable because of a tremendous number of tool modules in usual cases. Accordingly, this study proposes the optimum solution of (P), like a kind of the column generation method, by enumerating only those tool modules necessary for judging the optimality.

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This paper deals with the problem of evaluating two types of flexiblity in job shop. We compare machine flexibility and routing flexibility in terms of manufacturing performance under various environments from flow shop to random job shop. Based on the result, we present a basis of designing efficient flexible manufacturing systems.

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