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1	PDEModelica - Towards a High-Level Language for Modeling with Partial Differential Equations Saldamli, Levon January 2002 (has links) <p>This thesis describes initial language extensions to the Modelica language to define a more general language called PDEModelica, with built-in support for modeling with partial differential equations (PDEs). Modelica® is a standardized modeling language for objectoriented, equation-based modeling. It also supports component-based modeling where existing components with modified parameters can be combined into new models. The aim of the language presented in this thesis is to maintain the advantages of Modelica and also add partial differential equation support.</p><p>Partial differential equations can be defined using a coefficient-based approach, where a predefined PDE is modified by changing its coefficient values. Language operators to directly express PDEs in the language are also discussed. Furthermore, domain geometry description is handled and language extensions to describe geometries are presented. Boundary conditions, required for a complete PDE problem definition, are also handled.</p><p>A prototype implementation is described as well. The prototype includes a translator written in the relational meta-language, RML, and interfaces to external software such as mesh generators and PDE solvers, which are needed to solve PDE problems. Finally, a few examples modeled with PDEModelica and solved using the prototype are presented.</p> / Report code: LiU-Tek-Lic-2002:63. Object oriented programming mathematics models partial differential equations (PDEs) relational meta-language (RML) Computer science Datavetenskap
2	Análise da viabilidade da utilização do transporte por cabotagem para a movimentação de automóveis novos no Brasil: um estudo de caso / Analysis of feasibility to use cabotage for transporting new cars in Brazil: a case study Carolina Yuri Nakamura 15 April 2010 (has links) O objetivo desta dissertação é analisar a viabilidade do transporte marítimo de automóveis novos por cabotagem no Brasil, buscando uma alternativa de transporte, pois atualmente este transporte somente é realizado pelo modal rodoviário. A utilização da cabotagem como transporte de cargas tem aumentado desde a promulgação da Lei de Modernização dos Portos (lei 8.630), em 1993. Nesta mesma época, as fábricas de veículos começaram a passar por um processo de desconcentração geográfica, se deslocando da região Sudeste, e necessitando de transportes mais eficientes. Para observar se tal alternativa é viável economicamente, foi elaborado um estudo de caso e foram usados os dados de uma montadora específica. Esta montadora possui fábricas nos municípios de Camaçari (BA) e de São Bernardo do Campo (SP) e precisa distribuir sua produção em 275 concessionárias espalhadas pelo país. A partir do levantamento e análise dos custos rodoviários e de cabotagem para o transporte de automóveis, foi desenvolvido um modelo de transporte solucionado com o uso de técnicas de programação linear cujas soluções a partir da minimização dos custos de transporte apontaram para o uso ou não da cabotagem. As rotas que apresentaram maiores ganhos econômicos têm como característica uma grande distância entre a fábrica e as concessionárias e uma proximidade dos portos de destino das concessionárias. / This study aims to examine the feasibility of costal shipping of new cars by cabotage in Brazil, searching for an alternative system, since, currently, this transport is performed solely by road transportation. The use of cabotage as cargo transportation has increased since the enactment of the Modernization of Ports Law (Act 8630) in 1993. Since then, automobile makers started to undergo a decentralization process, moving away from the Southeast, and, therefore, requiring more efficient transport. To evaluate the economical feasibility of this alternative, a case study was established and data were collected from a specific auto maker. The auto maker has plants in the cities of Camaçari (BA) and São Bernardo do Campo (SP) and needs to distribute its production to 275 authorized dealers across the country. From the study and analysis regarding road and cabotage costs for car transports, it was developed a transportation model whose solutions using linear programming techniques aim to mitigate transportation costs pointing to the use or not of cabotage. Routes that had greater economic yields are characterized by a large distance between the plant and dealers and proximity to destination ports of dealers. Automóveis - Produção Cabotagem Modelos matemáticos Programação Linear Transporte marítimo - Custos. Cars - Production Coastal Linear programming Maritime transport - Costs. Mathematics models
3	Análise da viabilidade da utilização do transporte por cabotagem para a movimentação de automóveis novos no Brasil: um estudo de caso / Analysis of feasibility to use cabotage for transporting new cars in Brazil: a case study Nakamura, Carolina Yuri 15 April 2010 (has links) O objetivo desta dissertação é analisar a viabilidade do transporte marítimo de automóveis novos por cabotagem no Brasil, buscando uma alternativa de transporte, pois atualmente este transporte somente é realizado pelo modal rodoviário. A utilização da cabotagem como transporte de cargas tem aumentado desde a promulgação da Lei de Modernização dos Portos (lei 8.630), em 1993. Nesta mesma época, as fábricas de veículos começaram a passar por um processo de desconcentração geográfica, se deslocando da região Sudeste, e necessitando de transportes mais eficientes. Para observar se tal alternativa é viável economicamente, foi elaborado um estudo de caso e foram usados os dados de uma montadora específica. Esta montadora possui fábricas nos municípios de Camaçari (BA) e de São Bernardo do Campo (SP) e precisa distribuir sua produção em 275 concessionárias espalhadas pelo país. A partir do levantamento e análise dos custos rodoviários e de cabotagem para o transporte de automóveis, foi desenvolvido um modelo de transporte solucionado com o uso de técnicas de programação linear cujas soluções a partir da minimização dos custos de transporte apontaram para o uso ou não da cabotagem. As rotas que apresentaram maiores ganhos econômicos têm como característica uma grande distância entre a fábrica e as concessionárias e uma proximidade dos portos de destino das concessionárias. / This study aims to examine the feasibility of costal shipping of new cars by cabotage in Brazil, searching for an alternative system, since, currently, this transport is performed solely by road transportation. The use of cabotage as cargo transportation has increased since the enactment of the Modernization of Ports Law (Act 8630) in 1993. Since then, automobile makers started to undergo a decentralization process, moving away from the Southeast, and, therefore, requiring more efficient transport. To evaluate the economical feasibility of this alternative, a case study was established and data were collected from a specific auto maker. The auto maker has plants in the cities of Camaçari (BA) and São Bernardo do Campo (SP) and needs to distribute its production to 275 authorized dealers across the country. From the study and analysis regarding road and cabotage costs for car transports, it was developed a transportation model whose solutions using linear programming techniques aim to mitigate transportation costs pointing to the use or not of cabotage. Routes that had greater economic yields are characterized by a large distance between the plant and dealers and proximity to destination ports of dealers. Automóveis - Produção Cabotagem Cars - Production Coastal Linear programming Maritime transport - Costs. Mathematics models Modelos matemáticos Programação Linear Transporte marítimo - Custos.
4	Contrast sensitivity of the human eye and its effects on image quality Barten, Peter G. J. January 1900 (has links) Thesis (doctoral)--Technische Universiteit Eindhoven, 1999. / Originally published: Knegsel : HV Press, 1999. Includes bibliographical references and index.
5	PDEModelica - Towards a High-Level Language for Modeling with Partial Differential Equations Saldamli, Levon January 2002 (has links) This thesis describes initial language extensions to the Modelica language to define a more general language called PDEModelica, with built-in support for modeling with partial differential equations (PDEs). Modelica® is a standardized modeling language for objectoriented, equation-based modeling. It also supports component-based modeling where existing components with modified parameters can be combined into new models. The aim of the language presented in this thesis is to maintain the advantages of Modelica and also add partial differential equation support. Partial differential equations can be defined using a coefficient-based approach, where a predefined PDE is modified by changing its coefficient values. Language operators to directly express PDEs in the language are also discussed. Furthermore, domain geometry description is handled and language extensions to describe geometries are presented. Boundary conditions, required for a complete PDE problem definition, are also handled. A prototype implementation is described as well. The prototype includes a translator written in the relational meta-language, RML, and interfaces to external software such as mesh generators and PDE solvers, which are needed to solve PDE problems. Finally, a few examples modeled with PDEModelica and solved using the prototype are presented. / <p>Report code: LiU-Tek-Lic-2002:63.</p> Object oriented programming mathematics models partial differential equations (PDEs) relational meta-language (RML) Computer Sciences Datavetenskap (datalogi)
6	Contrast sensitivity of the human eye and its effects on image quality / Barten, Peter G. J. January 1900 (has links) Thesis (doctoral)--Technische Universiteit Eindhoven, 1999. / Originally published: Knegsel : HV Press, 1999. Includes bibliographical references and index. Online version available. http://dx.doi.org/10.1117/3.353254
7	Contrast sensitivity of the human eye and its effects on image quality Barten, Peter G. J. January 1900 (has links) Thesis (doctoral)--Technische Universiteit Eindhoven, 1999. / Originally published: Knegsel : HV Press, 1999. Includes bibliographical references and index.
8	Uma contribuição ao estudo do efeito corona em linhas de transmissão / A contribution to the study of the corona effect in transmission lines Freitas, Michelly Alcantara de 15 June 2007 (has links) Orientadores: Jose Pissolato Filho, Sergio Kurokawa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-09T06:33:17Z (GMT). No. of bitstreams: 1 Freitas_MichellyAlcantarade_M.pdf: 1141604 bytes, checksum: a3e880984ac7598f64499a8ad34269b7 (MD5) Previous issue date: 2007 / Resumo: Neste trabalho é mostrado um estudo a respeito do efeito corona em linhas de transmissão. A linha de transmissão foi representada por meio de uma cascata de circuitos 1t e o efeito da freqüência sobre os parâmetros longitudinais da linha foi representado por meio de uma associação série e paralela de resistores e indutores. Neste trabalho o efeito corona foi representado por meio dos modelos de Gary e de Skilling-Umoto devido ao fato destes modelos permitirem a sua inserção na cascata de circuitos 1t. O sistema mencionado anteriormente foi utilizado para representar a linha por meio de variáveis de estado, onde as equações de estado são a corrente longitudinal e a tensão transversal em cada um dos circuitos 1t. O modelo desenvolvido foi utilizado para simular as sobretensões originadas por uma descarga atmosférica em uma linha monofásica. Os resultados obtidos foram comparados com resultados experimentais mostrados em outros trabalhos. Esta comparação mostrou que os resultados obtidos com o modelo proposto são bem próximos aos resultados obtidos experimentalmente. / Abstract: In this work it is presented a study about the corona effect in transmission lines. The line was represented as being a cascade of 1t circuits and the frequency dependence of the longitudinal parameters of the line was synthesized with series and parallel resistors and inductors. In this work was used the Gary's model and Skilling-Umoto model for representing the corona effect because they can be inserted in the cascade. of 1t circuits. With the system above mentioned, a state model of the line was obtained using longitudinal currents and transversal voltages in each 11 circuit as the state variables. The proposed model was used to simulate the over voltages resulting of a lighting surge in a single-phase line. The simulation results were compared with experimental results that are available in several papers. It is possible to conclude that results obtained with proposed model are in agreement with experimental results. / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica Linhas elétricas aéreas Corona (Eletricidade) Transitórios (Eletricidade) Modelos matemáticos Energia elétrica - Transmissão Area eletric lines Corona (Eletricity) Transients (Eletricity) Mathematics models Eletric power - Transmission
9	Análise de redes sociais em dados bibliográficos / Social network analysis on bibliographical data Pacheco, Urubatan Rocha 11 August 2010 (has links) Orientador: Ricardo de Oliveira Anido / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-17T02:21:18Z (GMT). No. of bitstreams: 1 Pacheco_UrubatanRocha_M.pdf: 1174940 bytes, checksum: d2b5f4af6749eb4a1c7c6a1810b9749a (MD5) Previous issue date: 2010 / Resumo: O foco deste trabalho é viabilizar a análise estrutural em redes sociais de colaboração científica a partir de bases de dados bibliográficos. Os dados bibliográficos são utilizados para obter redes sociais de afiliação dos autores a instituições de pesquisa científica, e das publicações são extraídas as suas relações com ontologias de áreas de pesquisa. Foram estudados e aplicados métodos que utilizam a análise das redes sociais para solução/redução de ambiguidades em identidades de nomes de pesquisadores, instituições, e veículos científicos. Outro assunto estudado foi a abordagem de medida da qualidade dos resultados e os problemas que afetam a sua qualidade. Concretizando o objetivo deste trabalho, foram construídas métricas e ferramentas que permitem a comparação da produção científica entre instituições, departamentos, áreas de pesquisa, países, etc. As ferramentas também produziram um ranking de universidades baseado no prestígio dos pesquisadores destas universidades na rede social de co-autoria. Este resultado permitiu demonstrar que a informação estrutural de prestígio foi devidamente capturada ao correlacionar este ranking com outros que avaliam a qualidade da produção científica das universidades utilizando critérios semelhantes. / Abstract: This work performs social network analysis of the scientific collaborations extracted from bibliographic data bases. The analysis also includes the authors' scientific institution afiliation, and its relation with the main scientific publications and with research subject ontologies. We studied and applied methods that use social network analysis to solve or mitigate the problem of ambiguity in researchers' identities. We also applied the methods for ambiguity resolution for names of institutions, scientific meeting venues, country/state names, etc. Another study subject was measuring the quality of the results. Finally we developed metrics and implemented tools that allow the comparison of the scientific production of institutions, researcher groups, research subjects fields, countries, etc. The tools also produced a ranking of universities based on the prestige of these universities researchers at the co-authorship social network. These results demonstrated that prestige structural information was properly captured showing its correlation with other works that assess the quality of scientific production of universities using similar criteria. / Mestrado / Metodologia e Tecnicas da Computação / Mestre em Ciência da Computação Algoritmos Análise por agrupamento Recuperação da informação Classificações bibliográficas Indexação automática Banco de dados bibliográficos Networks, Social - Mathematics models Algorithms Cluster analysis Information retrieval Bibliographic classification Automatic indexing Information science Data libraries
10	Itérations chaotiques pour la sécurité de l'information dissimulée / Chaotic iterations for the Hidden Information Security Friot, Nicolas 05 June 2014 (has links) Les systèmes dynamiques discrets, œuvrant en itérations chaotiques ou asynchrones, se sont avérés être des outils particulièrement intéressants à utiliser en sécurité informatique, grâce à leur comportement hautement imprévisible, obtenu sous certaines conditions. Ces itérations chaotiques satisfont les propriétés de chaos topologiques et peuvent être programmées de manière efficace. Dans l’état de l’art, elles ont montré tout leur intérêt au travers de schémas de tatouage numérique. Toutefois, malgré leurs multiples avantages, ces algorithmes existants ont révélé certaines limitations. Cette thèse a pour objectif de lever ces contraintes, en proposant de nouveaux processus susceptibles de s’appliquer à la fois au domaine du tatouage numérique et au domaine de la stéganographie. Nous avons donc étudié ces nouveaux schémas sur le double plan de la sécurité dans le cadre probabiliste. L’analyse de leur biveau de sécurité respectif a permis de dresser un comparatif avec les autres processus existants comme, par exemple, l’étalement de spectre. Des tests applicatifs ont été conduits pour stéganaliser des processus proposés et pour évaluer leur robustesse. Grâce aux résultats obtenus, nous avons pu juger de la meilleure adéquation de chaque algorithme avec des domaines d’applications ciblés comme, par exemple, l’anonymisation sur Internet, la contribution au développement d’un web sémantique, ou encore une utilisation pour la protection des documents et des donnés numériques. Parallèlement à ces travaux scientifiques fondamentaux, nous avons proposé plusieurs projets de valorisation avec pour objectif la création d’une entreprise de technologies innovantes. / Discrete dynamical systems by chaotic or asynchronous iterations have proved to be highly interesting toolsin the field of computer security, thanks to their unpredictible behavior obtained under some conditions. Moreprecisely, these chaotic iterations possess the property of topological chaos and can be programmed in anefficient way. In the state of the art, they have turned out to be really interesting to use notably through digitalwatermarking schemes. However, despite their multiple advantages, these existing algorithms have revealedsome limitations. So, these PhD thesis aims at removing these constraints, proposing new processes whichcan be applied both in the field of digital watermarking and of steganography. We have studied these newschemes on two aspects: the topological security and the security based on a probabilistic approach. Theanalysis of their respective security level has allowed to achieve a comparison with the other existing processessuch as, for example, the spread spectrum. Application tests have also been conducted to steganalyse and toevaluate the robustness of the algorithms studied in this PhD thesis. Thanks to the obtained results, it has beenpossible to determine the best adequation of each processes with targeted application fields as, for example,the anonymity on the Internet, the contribution to the development of the semantic web, or their use for theprotection of digital documents. In parallel to these scientific research works, several valorization perspectiveshave been proposed, aiming at creating a company of innovative technology. Dissimulation d'informations Étalement de spectre Exposant de Lyapunov Internet Iterations chaotiques Modèles mathématiques Preuve de sécurité Protection des documents numériques Robustesse Sécurité informatique Sécurité des données Sécurité topologique Stéganalyse Stéganographie Stégo-sécurité Syqstèlesss dynamiques discrets Tatouage numérique Tests applicatifs Théorie du chaos Topologie Vie privée Application tests Chaotiques iterations; Chaos theory Computer security Data hiding Data security Digital Watermarking Discret dynamycal systems Internet Lyapunov exponent Mathematics models Privacy Protection of digital documents Robustness Security proofs Spread spectrum Steganalysis Steganography Stego-security Topological security Topology 005.8

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