STRACTURAL MORPHGENESIS AND OPTIMIZATION BY AUTONOMOUS DECENTRALIZED FINITE ELEMENT METHOD

近年来，结构工程中的找形分析、形状分析和结构优化设计取得了显著的进展。存在各种解决方法和程序来解决这些问题。近年来，仿生方法如进化计算（如遗传算法和免疫系统）在许多领域的应用迅速增加，本研究探讨了仿生方法在弹性结构形状分析和优化设计中的适用性。我们的主要解决方案的方法是开发与有限元法结合自主分散的概念。这个概念是生命或生物系统的特征之一。利用元胞自动机中的局部规则思想实现了模糊度的概念。在求解过程中引入了分散化的概念和松弛技术，从而有效地求解了代数方程组，并以弹性结构的形态发生为例说明了方法的有效性和正确性。它们是平面桁架结构的最小重量设计问题、空间桁架结构的最小重量设计问题和二维弹性体的自组织问题。

Recent advances on form finding analysis, shape analysis and optimum design of structures in structural engineering are remarkable. There exist various solution methods and procedures to solve these problems. In recent years, a rapid increase in the use of life-like or biological approach such as the evolutional computation (for example, the genetic algorithms )GA) and the immune system) have seen in many fields.In this research project the applicability of life-like approach to shape analysis, and optimum design of elastic structures is discussed. Our main solution method is developed with the finite element method in conjunction with the concept of autonomous decentralization. This concept is the one of characteristics in life or biological system. The concept of autonomousness is implemented with the idea of local rule in the cell automaton. And the concept of decentralization is introduced with the relaxation technique in solution procedure in order to solve effectively the system of algebric equations.As numerical examples, the morphgenesis of elastic structure is given in order to show the effectiveness and validity of our method. They are minimum weight design problems of plane truss, and spatial truss structures and self-organization problem in two-dimensional elastic body.