الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
This thesis deals with a nonlinear multiobjective problem of optimal design and control for composite laminated plates. The optimization objectives are the minimization of the postbuckling dynamic response and the maximization of the buckling loads with constraints on the control energy and laminate thickness. This problem is greatly important due to its wide applications in many industrial fields, in particular, the aerospace industry and the industry of large space structures which need new light materials with a high degree of flexibility and low natural damping. Most studies related to this topic are formulated based on the classical theories for special cases of boundary conditions. As it is known, the classical theories do not account for the shear deformation effect causing high errors in the predication of the design and control parameters. In addition, the optimization problems associated with the design and control of composite laminates in prebuckling range have been extensively studied, but relatively little attention has been directed to the optimization problem in the postbuckling range which need a nonlinear (large deflection) analysis. In the present study, an integrated approach for the simultaneous design and active control optimization is presented to determine the optimal level of closedloop control function, layer thicknesses and fibers orientation angles of composite laminated plates. The total elastic energy is taken as a measure of the laminate dynamic response. The optimization objectives are formulated based on a shear deformation theory including the vonkarman nonlinear effect. LiapunovBellman theory is used to obtain iteratively analytic solutions for the optimal control force and controlled buckled deflection. For this purpose, Liapunovfunction is taken as a sum of positive definite functions with different degrees. To assess the effectiveness of the present design and control optimization, two examples for threelayer symmetric and fourlayer antisymmetric laminates are presented with various cases of boundary conditions. Graphical studies are carried out to determine the discrepancy between the solutions obtained due to successive iterations. The influences of the boundary conditions, material and geometric properties on the optimization process are also studied.