Katsundo Hitomi

Optimization analysis for recycle-oriented manufacturing systems

Recycling has been recently recognized as one of effective tools for solving environmental problems. In this respect present and future manufacturing systems should take the recycling of materials used into consideration. This paper points out the issues contained in such a recycle-oriented manufacturing system, then the basic parts-flow in the products life cycle is clarified by taking account of re-use and re-production of the parts contained in the product. A model is constructed to maximize two measures of performance—total profit and recycling rate. This is solved by goal programming. Finally, a numerical example is used to demonstrate the effectiveness of the model proposed.

A STUDY OF ECONOMICAL MACHINING: AN ANALYSIS OF THE MAXIMUM-PROFIT CUTTING SPEED

Abstract Apart from the conventional theory of the minimum-cost or maximum-production cutting speed, a new concept of the machining conditions for maximizing the profit for the manufacturing enterprise was presented. Based upon this concept, an analysts of the maximum-profit cutting speed was made and the theoretical expression for it was deduced.

Integrating the production planning and cellular layout for flexible cellular manufacturing

Abstract This paper aims to design a flexible cellular layout and to discuss its methodology. The method integrates production planning and cellular layout in a long-run planning horizon. The integrated planning model is formulated as a mixed-integer problem (MIP},which contains two types of integer programming problems: determining (1) the production quantity for each product and (2) the timing of adjusting for the cellular layout in a finite planning horizon with dynamic demand situation. This decision problem is solved so as to minimize the sum of inventory-holding costs, group-setup costs, material-handling costs and layout-adjusting costs subject to the capacity constraint and the demand requirement. The Benders decomposition is used to solve the MIP. The dual problem obtained is solved by linear programming using large-scale programming techniques. In addition, a method is also presented to cope with an uncertainty by adjusting individual production rates from their initially planned levels on a ro...

Multiobjective Design Optimization of Machine-Tool Spindles

A method of multiobjective design optimization is presented in order to evaluate conflicting objectives in designing machine-tool spindles. A Pareto optimum set which shows a trade-off relationship between two objectives minimizing the total weight of the spindle and the static torsional or bending compliance, is derived using the Kuhn-Tucker necessary conditions for optimality, and through analyses of objective and constraint functions. Weighting factors between the two objectives are obtained on the Pareto optimum set. Expanded problems and numerical examples are given.

Strategic integrated manufacturing systems: the concept and structures

Abstract Important points of todays manufacturing are: technical innovation (new product development and factory automation), market-oriented production (multi-product, small-batch production and product diversification), and global manuctacturing (international production and multinational corporation). A context of integrating these basic manufacturing issues together as a manufacturing strategy may be called “ Strategic Integrated Manufacturing Systems ”. Computer-Integrated Manufacturing (CIM) systems are a realization of this concept. In this article Integrated Manufacturing System (IMS) is described as a procedure of product design, process design, implementation, and management. Then a CIM is recognized as an IMS with a common database. Manufacturing strategy by CIM is also discussed, aiming at unmanned production, multi-product, small-batch production, fast and optimized design, speedy product development, JIT (just-in-time) delivery, and strong merchandising activity. The relation of CIM to SIS (strategic information system) is also mentioned, together with human-centered flexible manufacture. A concept of appropriate manufacturing or socially useful production is stressed as a conclusion.

Manufacturing systems engineering: the concept, its context and the state of the art

Abstract ‘Manufacturing systems engineering’ is a unified approach to manufacturing technology (flow of materials) and production management (flow of information). This was first proposed as an academic subject in 1975 (Hitomi 1975 b), and has lately been recognized as potentially a second Industrial Revolution (White and Mitchell 1989). This article reviews the basic concepts of manufacturing systems within their historical perspective and summarizes the important decision-making procedures for efficient and economical production activities.

Design and scheduling for flexible manufacturing cells with automatic set-up equipment

SUMMARY A flexible manufacturing cell (FMC) has become of major interest recently as a new machining unit for low-volume, variety production. However, set-up operations for workpieces have not yet been automated in the usual FMC. In this paper, the design and scheduling problems for FMC with automatic set-up equipment are discussed. The FMC consists of a machining centre, an industrial robot, a loading-unloading station and an index-pallet changer. First, the design and control system of the FMC is explained. Then a scheduling algorithm is developed to achieve the minimum total production time in order to operate the FMC effectively. As this FMC has finite buffer spaces on the index-pallet changer, this model can be regarded as a two-machine flow-shop problem with finite buffer spaces. Next, an algorithm for determining the optimum number of buffer spaces is constructed to design the FMC using the results of scheduling. Finally, a numerical example is given for demonstrating the effectiveness of the propo...

Decision analysis for determining the optimum planning horizon in aggregate production planning

Abstract A generalized concept for ‘Planning Horizon’ is introduced based upon a property of an analytical solution to a multiperiod production planning problem converging into an extreme as a length of planning horizon increases. Two algorithms for determining the value of this new ‘Planning Horizon’ are proposed. One is for a model with stationary demand, and the other is for a model with trigonometric seasonal demand. A numerical example is given to show that the recommended decision algorithms can be employed simply for practical use.

The Japanese way of manufacturing and production management

Abstract As Japan has achieved a stable economic growth, Japan and Japanese companies are currently receiving world-wide attention. In this article some characteristics of Japanese manufacturing methods and production management are introduced, including flexible automation, group technology, the Toyota production system, the QC circle, lifetime employment, and product development. In addition, some financial aspects of Japanese companies and the government-industry relationship in Japan are also considered.

Manufacturing Technology in Japan

Abstract Japan, as a country, is viewed as a success in global manufacturing. This article describes present trends in Japanese manufacturing industries—technological innovations, market-oriented manufacturing, and international production. Production techniques that originated in Japan, such as just-in-time (JIT), quality circle activity, and total quality control (TQC), are explained. Japanese manufacturing industries are not as efficient as believed. By introducing a new performance measure called the efficiency index, which evaluates the efficiency of industrial sectors, Japans manufacturing industry is evaluated, and several causes of industrial inefficiency are examined. Indicating a large imbalance of material import and export in Japan, “socially appropriate production” is described as a means to gain manufacturing excellence while contributing to public wealth and welfare.