应机械工程学院和机械结构强度与振动国家重点实验室虞烈教授的邀请，美国内布拉斯加大学Cho W. S. To教授将于2011年10月12日至17日来我校进行学术交流，并为我校师生做讲座。

题目：OPTIMAL CONTROL OF LINEAR AND NONLINEAR NONSTATIONARY RANDOM VIBRATION OF MULTI-DEGREE-OF-FREEDOM SYSTEMS

时间：2011年10月14日（周五）上午9:00～11:00

地点：机械工程学院第3会议室（西2楼2层）

讲座人简介：

NAME:C. W. Solomon To

EDUCATION(degree, area, institution, year)

B.Sc. (Hons.), Mechanical Engineering, University of Southampton, 1973

M.Sc., Mechanical Engineering, University of Calgary, 1975

Ph.D., Sound and Vibration Studies, University of Southampton, 1980

APPOINTMENTS

Professor, University of Nebraska, 1996-present

Professor, University of Western Ontario, 1994-1996

Associate Professor and NSERC University Research Fellow, University of Western Ontario, 1986-1994

Visiting Professor, University of California at Berkeley, 1991-1992

Director, Nonlinear Dynamics Research Laboratory, Vibration Knowledge System Research Laboratory, Sound and Vibration Laboratory, University of Western Ontario, 1990-1996

Associate Professor and NSERC University Research Fellow, University of Calgary, 1985-1986

Assistant Professor and NSERC University Research Fellow, University of Calgary, 1982-1985

Visiting Professor, University of Calgary, 1981-1982

Consulting Engineer, Wolfson Unit for Noise and Vibration Control, University of Southampton, 1979-1980

Research Fellow, Institute of Sound and Vibration Research, 1975-1979

RESEARCH INTERESTS

Sound and Vibration Studies

Nonlinear, random and chaotic vibration, noise and vibration control of structures and machinery, signal analysis and machinery noise diagnostics.

Solid and Computational Mechanics

Nonlinear finite element method with emphasis on isotropic and anisotropic shell finite elements development and their applications, mechanical properties of carbon nanotubes.

System Dynamics and Control

Dynamics of multi-body systems under deterministic and stochastic excitations, stochastic optimal control of structures and systems.

Design

Design Methodology, computer-aided design.

TEACHING INTERESTS

General subjects in systems and design with special interests in vibration studies, machinery noise and vibration diagnostics, finite element analysis, and nonlinear random vibration.

讲座摘要：This lecture consists of two integral parts. The first part is concerned with the extension of the state covariance assignment (SCA) method of Skelton and associates to the optimal random vibration control of large scale complicated shell structures with distributed piezoelectric components and under stationary random excitations. It provides a direct approach for achieving performance goals stated in terms of the root-mean-square (RMS) values which are common in many engineering system designs. The large scale shell structures with distributed piezoelectric components of complicated geometrical configurations are approximated by the mixed or hybrid strain formulation based lower order triangular shell finite elements developed previously by the author and his associates. Each of these shell finite elements has three nodes. Every node has seven degrees of freedom (dof) which include three translational, three rotational and one electric potential dof. Computed results applying the proposed approach for a plate and a cylindrical shell structures with distributed piezoelectric components and under stationary random excitations are included to demonstrate its simplicity of use and efficiency of implementing the proposed approach.

The second part of this lecture deals with the generalization of the approach in the first part to multi-degree-of-freedom nonlinear systems under nonstationary random excitations. The Lyapunov equations for such systems and their solutions are considered. Computed results are included to show its simplicity and usefulness.

欢迎广大师生届时听讲座，研究生记学分

机械工程学院 2011-10-11