RIA: Development and Applications of the Distributed Elements Method for Analysis of Dynamic Systems

本项目研究动态系统建模的分布式单元方法(DEM)。它试图解决与经典的模态分析和特征函数展开方法相关的困难。振型分析技术只能模拟有限数量的振型，而特征函数展开法在数值模拟方面存在缺陷。DEM方法利用传递函数的概念，很容易适用于控制问题。它特别适合于符号计算，并允许直接评估复杂系统的动态特性，包括系统谱和振型、响应和稳定性。虽然振动问题将在这个项目中得到强调，但该方法在其他学科中也有潜在的应用，包括热传导和扩散。

This project addresses the Distributed Element Method (DEM) for modeling dynamic systems. It attempts to remedy difficulties associated with the classical methods of modal analysis and eigenfunction expansion. The modal analysis technique models only a finite number of modes, whereas the eigenfunction expansion method has disadvantages in numerical simulations. The DEM method uses the transfer function concept, and is easily adapted for control problems. It is particularly suitable for symbolic computation and allows direct evaluation of the dynamic characteristics of complex systems including system spectrum and mode shapes, response and stability. Although vibration problems will be stressed in this project, the methodology has potential applications in other disciplines, including heat conduction and diffusion.