Optimality in Parametric Systems

Abstract

The First International Conference on Finite Elements in Biomechanics was held in Tucson, Ariz. February 18-20, 1980. This conference, which was sponsored by the United States National Science Foundation and the College of Engineering of the University of Arizona, contained about 60 presentations which covered a wide variety of finite element applications in biomechanics. The conference organizers (editors of this book) invited the authors of 18 of these presentations to prepare manuscripts for publication in this book. The book starts with the introduction of a clinician's view and then a finite element specialist view of the method. G. T. Rab presents his views on the finite element method, special model problems with biologic materials, and problem of clinician-engineer collaboration. O. C. Zienkiewicz and D. W. Kelley then present the basic outline of the finite element process, its historical development, present trends, and its impact on the field of bioengineering. The remainder of the book presents a diverse array of finite element applications in biomechanics. Two chapters address the mechanics of biologic fluid flow. Normal mechanics of capillary flow, arterial flow, blood cell deformation, and peristaltic flow are discussed. Special problems of pulsatile flow through a stenosis and through an aneurysm are also considered. The application of the finite element method in soft tissue mechanics is demonstrated in an introductory chapter and a subsequent series of chapters dealing with the mechanics of the lungs and heart. Analyses of the role of interfacial forces in lung deformation, lung parenchyma, and the heart's left ventricle are discussed. The remainder of the book, and by far the most indepth treatment of a subject, is devoted to the finite element method applied to solid mechanics, predominantly orthopaedic problems. After a survey chapter on the role of finite element models in orthopaedics, subsequent chapters address specific orthopaedic applications. An application of the finite method to external fracture fixation devices is followed by studies of stress-morphology relationships in trabecular bone, stress distributions in the femoral head, intervertebral disk function, the mechanics of artificial joint fixation, cement-bone failure, the function of femoral endoprostheses, and head and neck injury mechanisms. This book assembles the highlights of what was a very interesting biomechanics conference. The presentations chosen for inclusion in this book survey well the diverse application of the finite element method to biomechanics problems and illustrate important problems unique to finite element modeling of biologic systems. The reader is introduced to problems associated with biologic variability, growth and maturation, nonlinear materials, anisotropic materials, incompressible materials, viscoelastic materials, and structural pathology. The book as a whole serves as an excellent introduction for the experienced finite element programmer to the applications and special problems of biologic sy...

Optimal control problems with multiple characteristic time points in the objective and constraints

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Sensitivity of Transfer Capability Margins with a Fast Formula

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Multicriteria Design of Oversampled Uniform DFT Filter Banks

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“…Apart from using the window method, it is also possible to use the minimax technique [9] instead of the least-squares technique to design (8). Once the cutoff frequency and the stop-band frequency is fixed, the minimax optimization problem can be solved quickly via the Remez exchange algorithm.…”

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