In this paper, a new grouping method for Group Technology using Self-Organizing Map (SOM) is proposed. The purpose of our study is to divide machines in a factory into any number of cells so that the machines in each cell can process a similar set of parts to increase productivity. A main feature of our method is to specify not only the number of the cells but also the maximum and minimum numbers of machines in a cell. Some experimental results show effectiveness of our proposed algorithm.

The present paper discusses an assembly line balancing problem (ALBP). ALBP discussed up to now does not consider rack spaces where tools or parts are stored. We introduce an extended resource planning and assembly line balancing problem that takes the rack space into account. An exact search method for solving the problem by using a graph structure, and a heuristics for the method are proposed. The proposed method is evaluated by computational experiments.

This paper describes a programming system, K-NET for the development of control software for flexible manufacturing systems composed of robots, numerically-controlled machines, transfer machines and automatic storage/retrieval systems. K-NET is based on a high-level Petri net which makes it simple to express operational functions such as synchronization, interlock and concurrence in sequence control. Petri net in K-NET is colored one in which tokens have attributes, and timed one which can provide a notion of stochastic time. K-NET provides many kinds of boxes having specific functions, and gates specified the firing condition and the token flow control with IF-THEN rules. On the other hand, procedural language can be also used for information processing. K-NET can support all development stages including general design, detailed design, programming and testing. K-NET has an editor to input control specifications expressed with Petri net; a simulator to verify edited specifications; a generator to convert the net to C source programs for a computer or to ladder diagrams for a programmable controller; a reporter to print control specifications; and a monitor to display controller status in real-time. K-NET has been used in the development of control software for an automated guided vehicle system, and results show a 2/3rds cost-saving over development with conventional methods in which only procedural language is used.