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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Proposta de reestruturação de uma familia de chassis de onibus atraves da analise modular / Proposal of reorganization of a bus chassis family through the modular analysis

Gimenez, Marcos Carazatto 20 February 2008 (has links)
Orientador: Franco Giuseppe Dedini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-10T21:06:52Z (GMT). No. of bitstreams: 1 Gimenez_MarcosCarazatto_M.pdf: 5243564 bytes, checksum: f06980474419baf0ce942eb2ee5cccdf (MD5) Previous issue date: 2008 / Resumo: Essa dissertação trata da reestruturação de uma família de chassis de ônibus através da análise modular. A partir de um chassi já em produção, que foi a referência dessa análise, identifica-se a arquitetura da região do motor e seus periféricos, para a formação de um modelo que permite desenvolver novas periferias do motor derivadas do chassi de referência. Através do levantamento do estado da arte da modularidade, foi possível utilizar técnicas, métodos e ferramentas para agrupamento dos módulos, identificação das interfaces, quantificação da modularidade e avaliação de impactos nos módulos devido à inserção de novos módulos ou ajustes das condições de contorno. O resultado é a formação de novas periferias do motor com alto grau de comunização e padronização dos módulos, componentes e sistemas. As conseqüências da unificação das arquiteturas do produto para o projeto são a redução do tempo de desenvolvimento e aumento da confiabilidade do projeto. A origem desse trabalho deriva da necessidade que as montadoras têm de adaptarem seus portfólios de veículos a cada mudança de legislação ambiental. Nos últimos anos, o meio ambiente passou a ser o centro das atenções, refletindo em legislações cada vez mais desafiadoras no controle de emissões de gases danosos à atmosfera. O não atendimento às legislações acarretaria perda de mercado e conseqüente redução de lucros. Nesse cenário, o motor e os seus periféricos passam a ter uma atenção especial, pois depende deles o atendimento dos limites de emissões. Esse trabalho busca auxiliar na reconfiguração da periferia do motor através de um modelo exeqüível baseado na modularidade e que apresentou resultados satisfatórios / Abstract: This thesis describes the reorganization of a bus chassis family through the modular analysis. The reference of this analysis was a chassis already in production. As a first step, it is important to identify the needs and features of the engine and the peripheral components for the creation of the model which allows us to develop new engine peripheral components derived from the reference chassis. Analyzing the state of the art of the modularity, it was possible to apply techniques, methods and tools for grouping the modules, interface identification, modularity measurement and impact evaluation on the modules due to new modules development or boundary condition adjustments. The result is the development of new engine peripherical components with high degree of standardization of the modules, components and systems. The consequences of the standardization of the product architectures to the project are the development time reduction and higher reliability of the project. The origin of this work started due to the necessity that the auto-industry plants have to in order to adapt their vehicle variants for each new emission legislation. In the last years, the environment started to be the center of attention, reflecting in more challenging emission legislation, each time more restrict in relation to the emissions of gases to the atmosphere. The unfulfillment of the legislations would produce the effect of market loss and consequently profit reduction. In this scenario, the engine and peripheral components start to have a special attention, because it will depend on them to fulfill the emission limits. The goal of this work is to redesign the engine periphery by means of a feasible model based on modularization and which produced satisfactory results / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
42

Evaluating the Application of Modularity to Reduce Market Risk in Technology Push Products

Hopkinson, Aaron John 07 March 2007 (has links) (PDF)
Technology push product development presents a number of challenges over the more typical market pull product development. Despite these challenges, enough advantages exist to motivate firms to develop technology push products at greater risk. Modularity is a tool that can address some of these challenges. Currently most research and application of modularity have focused on market pull product development efforts. The research in this thesis explores the value of modularity in technology push product development through the development of methods and the analysis of 68 example products including 35 technology push products. A method has been developed for quantifying the degree to which a product is market pull and technology push by applying scores derived from customer feedback. In the development of the scoring method, the meaning of the terms market pull and technology push have been explored and clarified allowing for beneficial application. The scoring method was applied to 68 example products and then statistically evaluated to determine the effect that the market pull and technology push scores have on the probability of product success. With the market pull and technology push scores as a basis for the probability of success, the effect of modularity in technology push products can be determined. The concept of technology modularity was introduced in comparison to product modularity. Each of the 35 technology push products was evaluated to determine the level of both product and technology modularity present. These levels are used to statistically evaluate the affect of modularity on the probability of product success. This research presents methods for determining if technology modularity can significantly improve the probability of product success with examples indicating its value and application. Technology modularity, and its application, is validated as an important concept for technology push product developers. Three example products are provided to illustrate the application of this research to improve product development decisions. The methods, results, and conclusions of this research provide product developers with a powerful tool to aid them in the successful development and commercialization of technology push products.
43

Modularidade aplicada ao projeto de uma máquina agrícola: estudo da relação entre a arquitetura do produto e seu processo produtivo.

AZEVEDO, Helenaldo Firmino de. 10 May 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-05-10T18:00:56Z No. of bitstreams: 6 HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap 0.pdf: 390788 bytes, checksum: 6bd35ca677af3ae9e83b876ed6778f92 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap I.pdf: 186004 bytes, checksum: 6dfececbfff0aed10c1d3d770ea09604 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap II.pdf: 498769 bytes, checksum: 413e390cc4732c2c636c54e5685a89c0 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap III.pdf: 716490 bytes, checksum: 88a70a183ecdc6c3302ef0c2d34f57b4 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap IV.pdf: 2750520 bytes, checksum: 3f6b80a72dea065762045499726ffd7c (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap V.pdf: 3212971 bytes, checksum: 4af10723b57412f888297c0c6f6bf73e (MD5) / Made available in DSpace on 2018-05-10T18:00:56Z (GMT). No. of bitstreams: 6 HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap 0.pdf: 390788 bytes, checksum: 6bd35ca677af3ae9e83b876ed6778f92 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap I.pdf: 186004 bytes, checksum: 6dfececbfff0aed10c1d3d770ea09604 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap II.pdf: 498769 bytes, checksum: 413e390cc4732c2c636c54e5685a89c0 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap III.pdf: 716490 bytes, checksum: 88a70a183ecdc6c3302ef0c2d34f57b4 (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap IV.pdf: 2750520 bytes, checksum: 3f6b80a72dea065762045499726ffd7c (MD5) HELENALDO FIRMINO DE AZEVEDO – DISSERTAÇÃO (PPGDesign) 2016_Cap V.pdf: 3212971 bytes, checksum: 4af10723b57412f888297c0c6f6bf73e (MD5) Previous issue date: 2016-12-16 / O objetivo deste trabalho é analisar os impactos da modularização no desenvolvimento de produtos e no sistema produtivo de uma organização. O método utilizado foi o Modular Function Deployment (MFD) e a aplicação foi realizada em uma máquina de processamento de forragem animal. Os resultados alcançados com a modularização mostram que houve reduções de peças e de processos de fabricação com a modularização do produto. Diante desses resultados foi possível concluir que os impactos foram positivos tanto no desenvolvimento do produto como no sistema produtivo da organização em função da racionalização da produção, redução dos custos e possível aumento da produtividade. / This present work aims to analyze the impacts of modularization on product development and on the productive system of a particular organization. The chosen method was the Modular Function Deployment (MDF) and it was applied on a processing fodder machine. The results achieved with modularization shows reduction in the number of parts, likewise reduction in the number of manufacturing processes due to product’s modularization. Based on these results, it was possible to conclude that the impacts were positive both in product’s development stage and in the company production system due to production’s rationalization, costs reduction and a projected productivity increase.
44

MAINFRAME: Military acquisition inspired framework for architectural modeling and evaluation

Zellers, Eric M. 27 May 2016 (has links)
Military acquisition programs have long been criticized for the exponential growth in program costs required to generate modest improvements in capability. One of the most promising reform efforts to address this trend is the open system architecture initiative, which uses modular design principles and commercial interface standards as a means to reduce the cost and complexity of upgrading systems over time. While conceptually simple, this effort has proven to be exceptionally difficult to implement in practice. This difficulty stems, in large part, from the fact that open systems trade additional cost and risk in the early phases of development for the option to infuse technology at a later date, but the benefits provided by this option are inherently uncertain. Practical implementation therefore requires a decision support framework to determine when these uncertain, future benefits are worth the cost and risk assumed in the present. The objective of this research is to address this gap by developing a method to measure the expected costs, benefits and risks associated with open systems. This work is predicated on three assumptions: (1) the purpose of future technology infusions is to keep pace with the uncertain evolution of operational requirements, (2) successful designs must justify how future upgrades will be used to satisfy these requirements, and (3) program managers retain the flexibility to adapt prior decisions as new information is made available over time. The analytical method developed in this work is then applied to an example scenario for an aerial Intelligence, Surveillance, and Reconnaissance platform with the potential to upgrade its sensor suite in future increments. Final results demonstrate that the relative advantages and drawbacks between open and integrated system architectures can be presented in the context of a cost-effectiveness framework that is currently used by acquisition professionals to manage complex design decisions.
45

Evolução e integração morfológica do crânio dos roedores da subfamília Sigmodontinae Wagner, 1843 (Rodentia, Cricetidae) / Morphological integration and evolution on Sigmodontinae rodent skulls Wagner, 1843 (Rodentia, Cricetidae)

Costa, Bárbara Maria de Andrade 19 December 2013 (has links)
A subfamília de roedores Sigmodontinae representa o clado com a maior diversidade e distribuição de mamíferos na região neotropical, sendo que a maior parte das espécies são endêmicas da América do Sul. Com inúmeras diferenças ecomorfológicas, o padrão de diversificação desses roedores, por um ponto de vista biogeográfico e filogenético, tem sido bastante debatido. Nesta tese, busco compreender a evolução dos caracteres cranianos dos sigmodontíneos, a partir do arcabouço teórico da genética quantitativa e integração morfológica. Dessa forma, tive como objetivo geral avaliar os padrões e as magnitudes de integração morfológica para compreender a associação dos caracteres e explorar suas potenciais consequências evolutivas no crânio dos Sigmodontinae. A partir de um banco de dados contendo 2897 indivíduos de 39 espécies da subfamília, testei a similaridade estrutural das matrizes de correlação e covariância ao compará-las entre todos os táxons medidos (representados por 35 medidas cranianas). Avaliei também se a história evolutiva do grupo teve influência sobre os padrões da estrutura de covariância fenotípica. Além disso, testei a presença de módulos no crânio desses roedores, a partir das hipóteses de desenvolvimento e função comum nos crânios dos mamíferos. Por fim, simulei seleção natural nesses crânios a fim de investigar as possibilidades evolutivas na associação dos caracteres cranianos nos diferentes táxons da subfamília. De uma maneira geral, os sigmodontíneos apresentaram um padrão das relações dos caracteres muito semelhante, enquanto a magnitude em que esses caracteres estão integrados variou bastante entre as espécies sendo que a amplitude dessa variação foi próxima a que já foi detectada entre outras ordens de mamíferos eutérios. Além disso, tanto os padrões quanto as magnitudes obtidas não estiveram, até um certo ponto, associadas a história evolutiva (filogenia) desses roedores. Dessa forma, observa-se que após um período de diversificação de aproximadamente 12 milhões de anos, a plasticidade na magnitude de integração acoplada ao fato que esta magnitude nunca se aproxima de 1 (portanto com algum grau de flexibilidade) pode fornecer uma explicação sobre como a grande diversidade morfológica craniana surgiu neste grupo de mamíferos, mesmo com a grande conservação nos padrões de integração. Mais ainda, os sigmodontíneos compartilham um padrão de modularidade craniana comum entre a maioria das espécies, relacionada com as hipóteses funcionais e de desenvolvimento testadas. O padrão de modularidade mostrou-se influenciado pela variação de tamanho, associado ao primeiro componente principal (CP1) de todas as espécies, assim como a magnitude geral de integração do crânio. Quanto maior a variância alométrica no CP1 maior a magnitude de associação entre os caracteres do crânio e, dessa maneira, menos modular é o crânio. Essa relação é importante para compreender o potencial da resposta evolutiva, pois, independente da direção da pressão seletiva, espécies com maior magnitude geral de integração dos caracteres são mais restritas evolutivamente, ou seja, tendem a responder à seleção na direção do eixo de maior variação (tamanho). Em contrapartida, espécies com menores magnitudes entre os caracteres cranianos são mais flexíveis a responder na direção em que seleção está atuando. Interessantemente, os sigmodontíneos apresentaram potenciais evolutivos tanto próximo dos mamíferos mais flexíveis (primatas e morcegos) quanto daqueles que possuem os maiores índices de restrição (marsupiais) / The Sigmodontinae subfamily of rodents represents the clade with the greatest diversity and distribution among mammals in the Neotropical region, with most of the species endemic to South America. With numerous ecomorphological differences, the diversification pattern of these rodents, from a phylogenetic and biogeographic point of view, has been intensely debated. In this thesis, I seek to understand the evolution of the cranial traits of the sigmodontine, using the theoretical framework of quantitative genetics and morphological integration. Thus, I aimed at evaluating the patterns and magnitudes of morphological integration, to understand the association of traits and to explore the potential evolutionary consequences of these associations for the Sigmodontinae skull. Using a collected database containing 2897 individuals of 39 species of the subfamily, I tested the structural similarity of covariance and correlation matrices by comparing them between all measured taxons (represented by 35 cranial measurements). I also evaluated if the evolutionary history of the group had an influence on the patterns of phenotypic covariance structure. Furthermore, I tested the presence of modules in these rodents skulls, employing shared developmental and functional hypothesis proposed for mammalian skulls. Finally, I simulated natural selection in these skulls in order to investigate the evolutionary possibilities in the association of cranial traits in different taxa of the subfamily. In general, the sigmodontine had very similar patterns of traits relationship, while the magnitude of trait association varied greatly among species, and the amplitude of this variation was close to what has already been detected within other Eutheria mammalian orders. In addition, both the patterns as well as the magnitudes obtained were not, to a large extent, associated with the evolutionary history (phylogeny) of these rodents. Thus, I observed that after a period of diversification of approximately 12 million years, this magnitude of integration plasticity coupled with the fact that the magnitude of association is never 1 (granting some degree of flexibility), may provide an explanation for how the wide diversity in cranial morphology appeared in this mammalian group, even with the wide conservation in the integration patterns. Moreover, the sigmodontine share a common pattern of cranial modularity among most species, which are related to the tested functional and developmental hypotheses. The modularity pattern appears to be influenced by variation in size, associated with the first principal component (PC1) of all species, as well as the overall magnitude of skull integration. The greater the variance in the allometric PC1, the greater the association between the skull traits and, thus, the skull is less modular. This relationship is important to understand the potential of the evolutionary response, seeing that, independent of the direction of selective pressure, species with higher general integration magnitude are more evolutionarily constrained, i.e, tend to respond to selection in the direction of the axis with the greatest variation (size). In contrast, species with smaller magnitudes between cranial characters are more flexible to respond in the direction in which selection is acting. Interestingly, the sigmodontine exhibited a potential to evolutionary responses that range from much flexible, both close to mammals (primates and bats ), as well as with those who have the highest levels of restriction (marsupials)
46

Análise morfológica craniana de Xenartha atuais e extintos: inferências evolutivas e funcionais / Extant and extinct Xenarthran skull morphological analysis: evolutionary and functional inferences

Hubbe, Alex 25 April 2013 (has links)
Os Xenarthra representam um clado de mamíferos eutérios. Pouco se sabe sobre a evolução morfológica craniana do grupo. Esta tese iniciou os estudos relativos a esta questão com base na genética quantitativa, na morfometria e na sistemática, e teve por objetivos específicos: 1) avaliar empiricamente se as matrizes de variância e covariância fenotípica (matriz-P) dos diversos gêneros de Xenarthra estudados podem ser utilizadas como substitutas das respectivas matrizes de variância e covariância genética aditiva (matriz-G), uma vez que não existem matrizes-G estimadas para os Xenarthra, e também se elas podem ser utilizadas em estudos macroevolutivos; 2) testar se a diversificação morfológica craniana no grupo ocorreu somente através de deriva genética; e 3) compreender como a relação entre os caracteres morfológicos (módulos) e a magnitude geral de integração podem influir na evolução morfológica craniana. Além destes objetivos focados na evolução do grupo, também foi escopo desta tese inferir o hábito alimentar de taxa fósseis do final do Pleistoceno/início do Holoceno para melhorar o conhecimento sobre a ecologia de alguns grupos fósseis. O banco de dados utilizado foi composto por medidas lineares de aproximadamente 1150 espécimes adultos, representando 12 dos 14 gêneros atuais e sete dos diversos gêneros extintos de Xenarthra. Com base nesses dados, matrizes-P de variância e covariância e de correlação foram estimadas para cada gênero. Essas matrizes foram posteriormente comparadas par a par para avaliar a semelhança na estrutura das diferentes matrizes. Também a partir dessas matrizes, foram obtidas as variâncias entre e intra populações para testar se a diversificação morfológica ocorreu de acordo com a expectativa teórica de diversificação sob a ação exclusiva de deriva genética. As mesmas matrizes-P foram comparadas a diferentes matrizes teóricas de hipóteses de modularidade craniana. As matrizes teóricas expressaram a relação entre os caracteres com base no desenvolvimento e/ou desempenho de função compartilhado pelas partes do crânio. Para cada matriz-P de correlação calculou-se a magnitude geral de integração. Além disto, a dieta dos grupos extintos foi inferida através de análises de funções discriminantes a partir da relação entre forma e função dos animais atuais. Os resultados obtidos indicam que as matrizes-P dos diversos gêneros são similares entre si, o que sugere que matrizes-P podem ser utilizadas tanto como substitutas das matrizes-G quanto no contexto macroevolutivo. Os resultados obtidos refutaram a hipótese nula da diversificação morfológica craniana ocorrendo somente por deriva genética, ao menos nos níveis mais inclusivos da filogenia dos Xenarthra. Consequentemente, a seleção natural provavelmente atuou neste processo de diversificação. Os resultados também sugeriram que o crânio desse grupo está organizado em módulos, sendo os módulos mais conspícuos os relacionados à face. Além disso, foi detectada grande variação na magnitude geral de integração entre gêneros. A variação no padrão modular, mas principalmente na magnitude geral de integração, faz com que os gêneros apresentem diferenças nas possíveis capacidades de responder de forma alinhada às pressões seletivas. Por último, as análises morfofuncionais indicaram elevada diversidade de hábitos alimentares entre os Xenarthra extintos / Xenarthra are an eutherian mammal clade and little is known about their cranial morphological evolution. This thesis has initiated studies related to this topic and, based on quantitative genetics, morphometrics and systematics, aimed to: 1) empirically assess if the phenotypic variance and covariance matrices (P-matrix) of several genera can be used as surrogates for their respective additive genetic variance and covariance matrices (G-matrix), since G-matrices for Xenarthra are not available, and also if P-matrices can be used in macroevolutionary studies; 2) test whether the skull morphological diversification within the group occurred only through genetic drift; and 3) understand how the relationship between the traits (modules) and overall magnitude of integration may influence cranial morphological evolution. Besides these objectives focused on the evolution of the group, it was also within the scope of this thesis to infer the feeding habits of late Pleistocene/early Holocene fossil taxa to better understand the ecology of some fossil groups. The database used consist of linear measurements of approximately 1150 adult specimens, representing 12 of the 14 extant genera and seven of the several extinct genera of Xenarthra. The data gathered were used to estimate variance/covariance and correlation P-matrices for every genus. These matrices were compared between pairs of genera to evaluate the matrices\' structural similarities. Based on these matrices, within and between population variances were obtained and it was tested whether morphological diversification was in accordance to the theoretical expectation of diversification under genetic drift alone. The same matrices were compared to theoretical matrices expressing modularity hypotheses. These theoretical matrices represent the relationship among traits in reference to the shared development and/or function of different skull\'s anatomical regions (modules). For every correlation P-matrix the overall magnitude of integration was calculated. Moreover, the extinct groups\' diet was inferred through discriminant function analysis relying on the relationship between form and function of extant animals. Results indicate that P-matrices from several genera were structurally similar. This suggests that P-matrices can be used as surrogates of their G-matrices and in the macroevolutionary context. Results refuted the null hypothesis of cranial morphological diversification occurring only due to genetic drift, at least in more inclusive levels of Xenarthran phylogeny. Consequently, natural selection probably acted on this diversification process. The results also suggested that the Xenarthran skull is organized in modules, and the most conspicuous modules are in the face region. A large variation in the overall magnitude of integration among genera was detected. The variation in the modular pattern, but especially in the overall magnitude of integration, allows genera to differ in their potential capacity to respond aligned with selective pressures. Finally, morphofunctional analyses indicate a high diversity of feeding habits among extinct Xenarthra
47

Peshawar's 'emergent civil society' : the potential and limitations of its contribution to peacebuilding

Habib, Arshad January 2014 (has links)
This thesis argues that a peace-oriented struggle has emerged in Peshawar from within the non–state space and is demonstrated at the empirical level by various associations in that space. The struggle to embrace peace and reject different forms of violence, by this associational life in Peshawar is what we call an ‘emergent civil society’. The thesis argues against those who claim that civil society cannot exist or flourish in a non-western environment. Civil Society in Peshawar is emergent, as the empirical evidence suggests, but within an overarching tendency to root this in a local cultural identity. The latter is, however, imbued with values, belief systems, and gender roles, which limit the search for peace. Two examples are the dominance of a hyper masculinity and religious orthodoxies, which undermine forms of associationalism which might promote peace. To find an indigenous cultural identity, the ‘emergent civil society’ navigates, not without tensions, across three different worldviews that includes cultural (Pakhtunwali), religious (Islam) and, to a certain extent, liberal (human rights) perspectives. The tensions between different perspectives become more frictional when the ‘emergent civil society’ advocates women’s rights and religious pluralism, which is resisted by the antithetical forces of masculinity and religious orthodoxies. Amidst these contestations, the ‘emergent civil society’, while resisting these antithetical forces, pressurizes the state also to provide favourable conditions to continue its peace-oriented struggle. This thesis, however, suggests that the ‘emergent civil society’ also needs an in-ward looking tendency to self reflect on certain challenges that seem to impact the potential for growth and development of an associational life, which can fully embrace the social conditions for peace.
48

Exploring the Modularity and Structure of Robots Evolved in Multiple Environments

Cappelle, Collin 01 January 2019 (has links)
Traditional techniques for the design of robots require human engineers to plan every aspect of the system, from body to controller. In contrast, the field of evolu- tionary robotics uses evolutionary algorithms to create optimized morphologies and neural controllers with minimal human intervention. In order to expand the capability of an evolved agent, it must be exposed to a variety of conditions and environments. This thesis investigates the design and benefits of virtual robots which can reflect the structure and modularity in the world around them. I show that when a robot’s morphology and controller enable it to perceive each environment as a collection of independent components, rather than a monolithic entity, evolution only needs to optimize on a subset of environments in order to maintain performance in the overall larger environmental space. I explore previously unused methods in evolutionary robotics to aid in the evolution of modularity, including using morphological and neurological cost. I utilize a tree morphology which makes my results generalizable to other mor- phologies while also allowing in depth theoretical analysis about the properties rel- evant to modularity in embodied agents. In order to better frame the question of modularity in an embodied context, I provide novel definitions of morphological and neurological modularity as well as create the sub-goal interference metric which mea- sures how much independence a robot exhibits with regards to environmental stimu- lus. My work extends beyond evolutionary robotics and can be applied to the opti- mization of embodied systems in general as well as provides insight into the evolution of form in biological organisms.
49

What Is a Good Domain Description? Evaluating & Revising Action Theories in Dynamic Logic

Varzinczak, Ivan 27 October 2006 (has links) (PDF)
Traditionally, consistency is the only criterion for the quality of a theory in logic-based approaches to reasoning about actions. This work goes beyond that and contributes to the meta-theory of actions by investigating what other properties a good domain description should satisfy. Having Propositional Dynamic Logic (PDL) as background, we state some meta-theoretical postulates <br />concerning this sore spot. When all postulates are satisfied, we call the action theory modular. We point out the problems that arise when the postulates about modularity are violated, and propose algorithmic checks that can help the designer of an action theory to overcome them. Besides being easier to understand and more elaboration tolerant in McCarthy's sense, modular theories<br />have interesting computational properties. Moreover, we also propose a framework for updating domain descriptions and show the importance modularity has in action theory change.
50

The involvement of career and technical education advisory committees in modularizing curriculum

Malosh, Ann M. 14 November 2012 (has links)
The emergence of modularized curriculum in community college career and technical education (CTE) programs has received substantial attention over the last decade, with researchers suggesting that this type of curriculum redesign may assist with student retention and success. The purpose of this study was to describe advisory committee member involvement in modularizing CTE programs. This study was undertaken for three reasons: (a) to address the limited research on the topic of advisory committee involvement in modularizing curriculum; (b) to respond to the increased momentum to expand working lifetime opportunities, in which modularization may play an integral part; and (c) to explore the suggestion that employers must take a leadership role in shaping the workforce and that this may be done effectively through work on an advisory committee. The research was designed as a quantitative descriptive study using survey methodology. The study focused on community college CTE advisory committee members in Oregon and Wisconsin who were identified as being engaged in developing career pathways. The primary research question asked respondents to describe their involvement in modularizing curriculum, and the secondary question asked them to specific the degree to which their involvement had occurred in the various aspects of modularizing curriculum. The key findings of this descriptive study suggest that responding CTE advisory committee members in Oregon and Wisconsin are aware of the concept of curriculum modularization but have little involvement in the actual process of breaking down associate degree programs into smaller certificates. This study also shows that these same advisory committee members endorse more than they assist with developing the various aspects of modularizing curriculum, such as defining skills sets for various jobs, developing courses for appropriate content, reordering courses in an existing program, adding or deleting courses, and developing measureable outcomes. Implications for practice from this study are: 1) provide more information and training to advisory committee members involved in modularizing curriculum in order to increase their level of understanding and thus strengthen their ability to participate effectively in reviewing and endorsing work already done by faculty, 2) provide advisory committee members with complete and detailed instructions regarding their work on the committee, and 3) develop a mandatory advisory committee orientation for all members to provide the needed information and training. / Graduation date: 2013

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