Precision truing and dressing techniques using an electrophoretic phenomenon was developed for spherical resin-bonded diamond wheels with fine grains. Truing was carried out by bringing the wheel into contact with the anode, and dressing was carried out by bringing the wheel into contact With a gelled fiim on the anode. Both truing and dressing were conducted by moving the wheel around the cylindrical anode that was attached to an A. C. induction motor. In addition, the revolution speed of the anode was varied periodically to change the direction of the resultant velocity by means of which the wheel surface was scratched. It was connrmed through the truing test that the wheel surface was scratched multidirectionally so that alapped-like wheel surface without any unidirectional groove could be obtained. Also, it was confirmed by the dressing test that the gelled film on the anode behaved like a soft polisher, so that a sufficient chip pocket could be achieved without any residual damage on the bond surface.

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Recent developments in the precision grinding technology of advanced ceramics have been remarkable. However, ceramic swarf floating in grinding fluids causes scratches on the ground surface, deteriorating the surface finish. Ceramic swarf is extremely fine hard nomagnetic substance and this shape is relatively particulate with low specific gravity. Therefore, the removal of ceramic swarf by the conventional filtration system becomes very difficult. In this report, the experimental and theoretical analyses of the cross-flow microfiltration of grinding fluids were examined and the influence of swirling flow of suspension on the membrane permeation flux was clarified. A swirling flow type inlet was set on the front edge of a cross-flow microfiltration apparatus. Cross flow microfiitration of grinding fluids was carried out using a cellulose-type membrane for microfiltration, with a pore diameter of 1μm. The influences of Reynolds number, feed concentration on the membrane Permeation flux and the solute rejection, respectively were examined. A filtration model based on the lateral migration theory was applied to calculate the time-decline curve of the membrane Permeation flux. The calculated results agreed qualitatively with the experimental results and the adequacy of this model was confirmed.

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A method for determining whether a component part of mechanical products can be removed is necessary for design verification of the products. This problem has been solved by only considering contact states of component parts so far, though that is insufficient. In this paper, a component part is determined as removable when it can be moved to infinity with one translation without coiliding with other component parts. It is shown that a set of all directions along which a component part prohibited the other one from moving to infinity becomes a polyhedral convex cone when both component parts are given as convex polyhedrons. An algorithm for verifying the removability of a component part is developed. The algorithm takes O(N³_ν) time on the average, where N_υ is the number of vertices of a geometric model of mechanical product. The effectiveness of the developed algorithm is demonstrated by examples.

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This paper discusses the design problem of vehicles using multi-link suspension system with the aim of totally optimizing vehicle handling and stability. Since this problem includes many evaluation items, and multi-link suspension system has interconnected behavior, the optimization is so complicated. An efficient and computable model is indispensable for compromising the total optimization. This paper investigates a hierarchical structure of objectives, introduces appropriate simulation models for respective items, and formulates a mathematical optimization model based on them. Further, we apply a genetic algorithm based optimization method to this problem. The genetic algorithm is based on Simple GA and introduces several extensions such as fitness function for constrained multi-objective optimization problem, similarity-based selection, direct crossover within side constraints, etc. The result of optimization calculation shows the validity of the optimization model and the optimization algorithm as a mathematical computation based design methodology.

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The facility layout problem can be formulated as a combinatorial optimization problem to minimize the total cost owing to material flow. Most of the paper is focusing on such a layout problem in two-dimensions. However it would be better to treat the layout problem in three dimension (3 D) in order to minimize the distance between equipment and the land area. For binpacking problem, there are some papers in 3 D, but in those model flow between bin is not considered. That's why this paper proposed a 3 D-layout technique for unequal shape and area departments. Computational experiments are suggesting that proposed algorithm will produce better solution than plain layout which is the result of previous algorithm.

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In thisr esearch, the optimum design methods for material handling system in a seaport containerterminal are investigated. The optimum design for the container yard with transfer crane system is discussed in the present report. The simulation model is built both from the field survey and the analysis of handling mechanism for a transfer crane. As a result of simulation analysis, the optimum block size of container stowage for a transfer crane is derived. An index to evaluate the condition of delivery operation, that a container is loaded to tractor-trailer with a transfer crane, is defined as the queuing time irregularity. It describes the relationship between the inter-arrival time for tractortrailers and the stacking height for a transfer crane. For delivery operation, it is confirmed that 3container stacking is most effective in any case and that queuing time irregularity less than 1describes the optimum operation with no cumulative waiting time for tractor trailers.

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