<p>Research into the improvement of the Aircraft ConceptualDesign process by the application of MultidisciplinaryOptimization (MDO) is presented. Aircraft conceptual designanalysis codes were incorporated into a variety of optimizationmethods including Orthogonal Steepest Descent (full-factorialstepping search), Monte Carlo, a mutation-based EvolutionaryAlgorithm, and three variants of the Genetic Algorithm withnumerous options. These were compared in the optimization offour notional aircraft concepts, namely an advanced multiroleexport fighter, a commercial airliner, a flying-wing UAV, and ageneral aviation twin of novel asymmetric configuration. Tobetter stress the methods, the commercial airliner design wasdeliberately modified for certain case runs to reflect a verypoor initial choice of design parameters including wingloading, sweep, and aspect ratio.</p><p>MDO methods were evaluated in terms of their ability to findthe optimal aircraft, as well as total execution time,convergence history, tendencies to get caught in a localoptimum, sensitivity to the actual problem posed, and overallease of programming and operation. In all, more than a millionparametric variations of these aircraft designs were definedand analyzed in the course of this research.</p><p>Following this assessment of the optimization methods, theywere used to study the issue of how the computer optimizationroutine modifies the aircraft geometric inputs to the analysismodules as the design is parametrically changed. Since thiswill ultimately drive the final result obtained, this subjectdeserves serious attention. To investigate this subject,procedures for automated redesign which are suitable foraircraft conceptual design MDO were postulated, programmed, andevaluated as to their impact on optimization results for thesample aircraft and on the realism of the computer-defined"optimum" aircraft. (These are sometimes called vehicle scalinglaws, but should not be confused with aircraft sizing, alsocalled scaling in some circles.)</p><p>This study produced several key results with application toboth Aircraft Conceptual Design and MultidisciplinaryOptimization, namely:</p><p>    MDO techniques truly can improve the weight and cost ofan aircraft design concept in the conceptual design phase.This is accomplished by a relatively small "tweaking" of thekey design variables, and with no additional downstreamcosts.<i>In effect, we get a better airplane for free.</i></p><p>    For a smaller number of variables (<6-8), adeterministic searching method (here represented by thefull-factorial Orthogonal Steepest Descent) provides aslightly better final result with about the same number ofcase evaluations</p><p>    For more variables, evolutionary/genetic methods getclose to the best final result with far-fewer caseevaluations. The eight variables studied herein probablyrepresent the practical upper limit on deterministicsearching methods with today’s computer speeds.</p><p>    Of the evolutionary methods studied herein, the BreederPool approach (which was devised during this research andappears to be new) seems to provide convergence in the fewestnumber ofcase evaluations, and yields results very close tothe deterministic best result. However, all of the methodsstudied produced similar results and any of them is asuitable candidate for use.</p><p>    Hybrid methods, with a stochastic initial optimizationfollowed by a deterministic final "fine tuning", proved lessdesirable than anticipated.</p><p>    Not a single case was observed, in over a hundred caseruns totaling over a million parametric design evaluations,of a method returning a local rather than global optimum.Even the modified commercial airliner, with poorly selectedinitial design variables far away from the global solution,was easily "fixed" by all the MDO methods studied.</p><p>    The postulated set of automated redesign procedures andgeometric constraints provide a more-realistic final result,preventing attainment of an unrealistic "better" finalresult. Especially useful is a new approach defined herein,<i>Net Design Volume</i>, which can prevent unrealisticallyhigh design densities with relatively little setup andcomputational overhead. Further work in this area issuggested, especially in the unexplored area of automatedredesign procedures for discrete variables.</p>

No description available.

Thesis (MEng)--University of South Australia, 1997

The thesis begins with a review of the literature dealing with the incentives and disincentives for pursuing defence co-production policies in Western Europe. Political, economic and military aspects are each dealt with in turn, and their relative importance assessed. Following this section is a case study of the Panavia Multi-Role Combat Aircraft - the 'Tornado' - now in service with the air forces of West Germany, Britain and Italy. The study traces the progress of the MRCA programme from its initial conception through to production. The main theme of the case study is how the concerns of military-operational performance, cost-saving benefits, and programme efficiency were all secondary to government pursuit of wider political objectives. While the general literature was found to focus upon cost-savings in collaborative procurement, such savings are seen to be constrained or even determined by the outcome of frequently unrelated political decisions. Although set within the broad framework of national economic performance and the demands of social needs upon limited public expenditure budgets, these decisions are based upon government preferences rather than industrial or other lobby-group pressures. A cursory evaluation of the MRCA programme and the aircraft itself is included in the conclusion. The project is seen to have achieved mixed success, but with significant problems. / Arts, Faculty of / Political Science, Department of / Graduate

A relação entre os aspectos fílmicos e lúdicos dos jogos vão muito além da palavra videogame. Essa terminologia frente à humanidade é muito recente, apenas com algumas dezenas de anos, porém, trata-se de algo que converge em símbolos, técnicas e práticas, revestindo tais itens contemporâneos e impactando a sociedade significativamente. Logo, configura-se como um objeto de estudo capaz de promover reflexões diversas. No caso desta pesquisa, consideramos que nessa expressão do ato de jogar existe muito de game e pouco de vídeo. As abordagens focando as narrativas e as mecânicas muitas vezes deixam uma lacuna referente aos processos audiovisuais. Em função desta observação, foi realizado um estudo de cunho hipotético-dedutivo e metapórico preconizando uma visão integradora de três métodos distintos: a Ludologia, a Narratologia e a Linguagem Audiovisual. A motivação do título escolhido para o estudo de caso, Super Street Fighter IV, ocorreu por ser um jogo popular, dentro de um gênero típico de jogabilidade, que há mais de duas décadas se reinventa para agradar os fãs. Além disso, dialoga diretamente com temas culturais (costumes asiáticos e artes marciais) e temas cinematográficos (filmes de luta e o ícone representado por Bruce Lee). O estudo focou os resultados visando contribuir para uma compreensão do videogame, de modo que a pesquisa realizada pudesse trazer parâmetros tanto para aprofundar elementos presentes em sua linguagem quanto para o desenvolvimento de questões de ligadas à sua realização. / The relation between cinematographic and ludic aspects of games go well beyond the Word videogame. This term is very recent in human history, having appeared only a few decades ago. However, it is something the converges in symbols, techniques and practices, labelling these contemporary items and significantly impacting society. For this reason, it presents itself as a study subject that is capable of promoting diverse reflections and discussions. In this research, we considered that in this expression of the act of playing there is much more game than video. Approaches that focus on narratives and mechanics often don\'t refer to audiovisual processes. Based on this observation, we devised a hypothetic-deductive, and metaphoric study that considers three distinct methods: Ludology, Narratology, and Audiovisual Language. The motivation behind the chosen subject of study, Super Street Fighter IV, comes form it being a popular game, from a genre that is mainly based on playability, with more than two decades of reinvention in order to please fans. Besides, it directly dialogs with cultural (Asiatic costumes and martial arts) and cinematographic themes (fight movies and the popular icon Bruce Lee). The study focused the results in order to contribute to a comprehension of video-games, in a way that the research could bring parameters both to deepen elements that help better understanding this language, and to aid the development of questions concerned to realization.

Thesis (M.S.)--School of Advanced Air and Space Studies, 2008. / "June 2008." Vita. Includes bibliographical references (p. 130-134). Also available via the Internet.

Thesis (Ph. D.)--RAND Graduate School, 1993. / At head of title: Dissertation. "RGSD-106." Includes bibliographical references.

A relação entre os aspectos fílmicos e lúdicos dos jogos vão muito além da palavra videogame. Essa terminologia frente à humanidade é muito recente, apenas com algumas dezenas de anos, porém, trata-se de algo que converge em símbolos, técnicas e práticas, revestindo tais itens contemporâneos e impactando a sociedade significativamente. Logo, configura-se como um objeto de estudo capaz de promover reflexões diversas. No caso desta pesquisa, consideramos que nessa expressão do ato de jogar existe muito de game e pouco de vídeo. As abordagens focando as narrativas e as mecânicas muitas vezes deixam uma lacuna referente aos processos audiovisuais. Em função desta observação, foi realizado um estudo de cunho hipotético-dedutivo e metapórico preconizando uma visão integradora de três métodos distintos: a Ludologia, a Narratologia e a Linguagem Audiovisual. A motivação do título escolhido para o estudo de caso, Super Street Fighter IV, ocorreu por ser um jogo popular, dentro de um gênero típico de jogabilidade, que há mais de duas décadas se reinventa para agradar os fãs. Além disso, dialoga diretamente com temas culturais (costumes asiáticos e artes marciais) e temas cinematográficos (filmes de luta e o ícone representado por Bruce Lee). O estudo focou os resultados visando contribuir para uma compreensão do videogame, de modo que a pesquisa realizada pudesse trazer parâmetros tanto para aprofundar elementos presentes em sua linguagem quanto para o desenvolvimento de questões de ligadas à sua realização. / The relation between cinematographic and ludic aspects of games go well beyond the Word videogame. This term is very recent in human history, having appeared only a few decades ago. However, it is something the converges in symbols, techniques and practices, labelling these contemporary items and significantly impacting society. For this reason, it presents itself as a study subject that is capable of promoting diverse reflections and discussions. In this research, we considered that in this expression of the act of playing there is much more game than video. Approaches that focus on narratives and mechanics often don\'t refer to audiovisual processes. Based on this observation, we devised a hypothetic-deductive, and metaphoric study that considers three distinct methods: Ludology, Narratology, and Audiovisual Language. The motivation behind the chosen subject of study, Super Street Fighter IV, comes form it being a popular game, from a genre that is mainly based on playability, with more than two decades of reinvention in order to please fans. Besides, it directly dialogs with cultural (Asiatic costumes and martial arts) and cinematographic themes (fight movies and the popular icon Bruce Lee). The study focused the results in order to contribute to a comprehension of video-games, in a way that the research could bring parameters both to deepen elements that help better understanding this language, and to aid the development of questions concerned to realization.

Thesis (M. of Military Art and Science)--U.S. Army Command and General Staff College, 2007. / The original document contains color images. Title from title page of PDF document (viewed on May 27, 2008). Includes bibliographic references.

The comparison of aerodynamic characteristics for a combat aircraft studywas addressed in this work. The thesis is a feasibility study which reviewsthe workload and output quality efficiency of different numerical and experimentalmethods often used during conceptual aircraft design.For this reason the Vortex Lattice Method (VLM), Euler or Reynolds-Averaged-Navier-Stokes (RANS) simulations were compared to the moreheavier Large Eddy Simulation (LES) which also has the capability to capturealso more complex flow physics, such as those that occur, for example,at high angles of attack. To be able to crosscheck the numerical results,the same static alpha sweep tests were executed in a tunnel. Thereby itwas discovered that it was quite challenging to reach the same values in thewater tunnel as those previously calculated in computational fluid dynamics(CFD) due to different technical issues.However it could be shown that LES simulations can be today a suitabletool for conceptual aircraft design, as they offer much higher levels ofaccuracy and give the designer the possibility to check the new study at anearly stage along the border of the aircraft’s flight envelope.