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Mathematical and Computer Modelling Reports 1. Sound Vibr. Vol. 117. No. 3, pp. 475-496, 1987 379 MODELING AND CONTROL OF BEAM-LIKE STRUCTURES A. Hu, R. E. SKELTON and T. Y. YANG School of Aeronautics and Astronautics, Purdue University, West Lafayette, IN 47907, U.S.A. Abstract-The most popular finite element codes are based upon appealing theories of convergence of modal frequencies. For example the popularity of cubic element for beam-like structures is due to the rapid convergence of modal frequencies and stiffness properties. However, for those problems in which the primary consideration is the accuracy of response of the structure at specified locations it is more important to obtain accuracy in the modal costs than in the modal frequencies. The modal cost represents the contribution of a mode in the norm of the response vector. This paper provides a complete modal cost analysis for beam-like continua. Upper bounds are developed for mode truncation errors in the model reduction process and modal cost analysis dictates which modes to retain in order to reduce the model for control design purposes. Computers Sinrcl. Vol. 26, No. 6. pp. 887-897, 1987 APPLICATION OF A BOUNDING SURFACE MODEL TO BOSTON BLUE CLAY W. 0. MCCARRON and W. F. CHEN School of Civil Engineering, Purdue University, West Lafayette, IN 47907, U.S.A. Abstract-A formulation for an elastic-plastic Bounding Surface model for soils is presented. The model is calibrated and the predicted and measured response compared for laboratory stress paths and a boundary value problem. The predictions are reasonable, providing confidence in the model formulation, numeric implementation and numeric solution techniques. Possible improvements to the model are discussed. Furures pp. 403-430, 1987 GLOBAL MODELS A REVIEW OF RECENT DEVELOPMENTS SAM COLE School of Architecture and Environmental Design, SUNY at Buffalo, NY 14214, U.S.A. Abstract-This article summarizes recent developments in computerized global modelling. It is largely descriptive, and will be followed in further issues by articles dealing with more qualitative scenario approaches to global forecasting and an overall evaluation of current forecasting efforts. “.C M. 1213-1

Global models: A review of recent developments

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Mathematical and Computer Modelling Reports

1. Sound Vibr. Vol. 117. No. 3, pp. 475-496, 1987

379

MODELING AND CONTROL OF BEAM-LIKE STRUCTURES

A. Hu, R. E. SKELTON and T. Y. YANG

School of Aeronautics and Astronautics, Purdue University, West Lafayette, IN 47907, U.S.A.

Abstract-The most popular finite element codes are based upon appealing theories of convergence of modal frequencies. For example the popularity of cubic element for beam-like structures is due to the rapid convergence of modal frequencies and stiffness properties. However, for those problems in which the primary consideration is the accuracy of response of the structure at specified locations it is more important to obtain accuracy in the modal costs than in the modal frequencies. The modal cost represents the contribution of a mode in the norm of the response vector. This paper provides a complete modal cost analysis for beam-like continua. Upper bounds are developed for mode truncation errors in the model reduction process and modal cost analysis dictates which modes to retain in order to reduce the model for control design purposes.

Computers Sinrcl. Vol. 26, No. 6. pp. 887-897, 1987

APPLICATION OF A BOUNDING SURFACE MODEL TO BOSTON BLUE CLAY

W. 0. MCCARRON and W. F. CHEN

School of Civil Engineering, Purdue University, West Lafayette, IN 47907, U.S.A.

Abstract-A formulation for an elastic-plastic Bounding Surface model for soils is presented. The model is calibrated and the predicted and measured response compared for laboratory stress paths and a boundary value problem. The predictions are reasonable, providing confidence in the model formulation, numeric implementation and numeric solution techniques. Possible improvements to the model are discussed.

Furures pp. 403-430, 1987

GLOBAL MODELS A REVIEW OF RECENT DEVELOPMENTS

SAM COLE

School of Architecture and Environmental Design, SUNY at Buffalo, NY 14214, U.S.A.

Abstract-This article summarizes recent developments in computerized global modelling. It is largely descriptive, and will be followed in further issues by articles dealing with more qualitative scenario approaches to global forecasting and an overall evaluation of current forecasting efforts.

“.C M. 1213-1