Invited Speaker---Prof. Mitsukuni Matayoshi


Department of Industry and Information Science, Okinawa International University

Biography: Mitsukuni Matayoshi is a full-time professor in Department of Industry and Information Science, Okinawa International University. His research area: solving combinatorial optimization problems by using evolutionary computation approaches, especially the method what is mainly used is genetic algorithm (GA); studying traditional dyeing and weaving techniques.

Speech Title: Two dimensional rectilinear polygon packing using genetic algorithm with a hierarchical chromosome
Abstract: I have proposed a packing method for right-angled polygon by using Genetic Algorithm (GA) with a new type of chromosome structure. The proposed chromosome structure has a hierarchical chromosome structure, which has one single straight chromosome and one double chromosome. The genes, which are in the single straight chromosome, represent right-angled polygons to be packed. And the sequence of genes in the single straight chromosome means the packing order for objects onto the target container. On the other hand, double chromosome shows the connections among right-angled polygons correspond to genes in a single straight chromosome. Here, the structure of the double chromosome is based on the idea of corner junction method for packing two dimensional rectangles onto a container and introduced from my previous study. Experimental results show the proposed method is succeeded in placement of some complicated two dimensional right-angled polygons in feasible time. However, some problems still remains that should be solved. One of the complicated issue is how to divide right-angled polygon into rectangles. The rectangles make junction points for packing right-angled polygons finally. The another issue belongs under future work. The proposed method can pack right-angled polygons but can't pack polygons without a square corner.