This book contains 36 papers presented at the Sixth International Conference on Computer Aided Optimum Design of Structures (OPTI 99),held in Orlando, Florida, March 16-18, 1999. The conferences have been held every two years since 1989, alternately in the US and Europe. The conferences have provided structural optimization researchers from around the world the opportunity to exchange new ideas. The book thus provides state-of-the-art information on the research and industrial applications of structural optimization.

The practical applications of structural optimization techniques, which are well recognized by industry, offer important advantages in the design of aircraft and are used in the analysis of automotive, civil and mechanical engineering components. Computer-aided structural design is enhanced by adding optimization software; its influence cannot be over emphasized. By linking both techniques, integrated packages for structural optimization are obtained. These packages provide a means to find solutions for some of the most difficult problem challenges in engineering.

Design and optimization of designs are the pillars of engineering. Both have greatly benefited from the phenomenal growth of raw computational capability now routinely available to engineers. Furthermore, with the maturing of analysis techniques such as the finite element and boundary element methods, engineers can now undertake complex parametric design and decision-making while considering realistic configurations. Remarkably, analysis and optimization is now often carried out on a desktop platform. Advanced computer graphics, which are now commonplace in all research and industrial settings, have also done much to facilitate the input/output phases of analysis and design and interpretation of results. The integration of computer-aided design and multi-objective/disciplinary optimization is becoming prevalent in all aspects of industry and research, spanning such problems as the design of automobiles, aircraft, bridge structures and space vehicles. Conference participants included delegates from universities, private and public research centers, as well as from industry. Computer-aided design and optimization are themes which run through the papers contained in these proceedings. Subjects presented included shape optimization, optimal control , multi-objective and expert systems optimization, as well as linear and non-linear structural optimization, and integrated packages for optimum design. Papers are also included on the subjects of advances in numerical optimization addressing genetic algorithms and parallel computing. Finally, a series of contribution are devoted to applications of optimization to mechanical engineering design issues such as increasing component reliability and optimal design of reinforced members to ensure crash worthiness.