2007 年 2007 巻 p. 31-36
Self-organization phenomena are often observed in various fields of engineering including chemical and biological engineering. The self-organization can generate complex spatio-temporal patterns. The analysis of the spatio-temporal patterns created by the self-organization is one of major nonlinear problems in engineering. For example, the analysis of the spatio-temporal patterns in phase transitions of polymeric materials is essential to develop new materials. In this paper, we analyze chemotactic bacterial colony patterns in the semi-solid media as the patterns created by the self-organization. Focusing on bacterial species Escherichia coli (E. coli) among the chemotactic bacteria, we study the influence of the disturbances such as impurities in the semi-solid media on the colony formation by numerical simulations.