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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.
91

Effet de l'écologie d'un hôte sur l'évolution de son principal parasitoïde

Dion, Emilie 31 May 2011 (has links) (PDF)
Chaque être vivant interagit avec une ou plusieurs espèces et est membre d'un réseau complexe d'interactions qui influencent les traits des individus, exerçant de fait des pressions sélectives sur leurs populations. Chaque espèce étant dépendante de la nature et de la diversité des interactions dans lesquelles elle est impliquée, son évolution est donc en partie liée aux autres espèces avec lesquelles elle interagit. Un hôte et son parasitoïde vivent dans une dynamique coévolutive, prenant part à une véritable 'course aux armements', où les différentes stratégies d'attaque peuvent être sélectionnés chez le parasitoïde en réponse aux différentes formes de défenses chez l'hôte. Ce dernier interagit également avec d'autres organismes qui modifient ses traits, impactant les aptitudes du parasitoïde, perturbant leur dynamique coévolutive. L'objectif de ce travail est ainsi d'identifier l'influence du réseau d'interactions du puceron du pois Acyrthosiphon pisum sur l'évolution et l'écologie des populations de son principal parasitoïde Aphidius ervi. Le puceron du pois est lui-même parasite de sa plante hôte, leur coévolution aboutissant à une spécialisation de cet aphide cette espèce hôte végétale. Les populations de pucerons sont donc structurées en races d'hôtes sympatriques, divergeant génétiquement et phénotypiquement. Notre étude montre une absence de structuration génétique des populations de parasitoïdes selon les races d'hôte. A. ervi exploite indifféremment les A. pisum issus de différentes plantes hôtes, excluant la présence d'un effet cascade associé à la spécialisation alimentaire chez ce puceron. La dispersion et le caractère généraliste du parasitoïde semblent favoriser les flux de gènes entre les différents éléments d'un paysage agricole. A. pisum peut également abriter le symbiote Hamiltonella defensa qui lui confère une résistance à A. ervi. Ces microorganismes symbiotiques induisent une réduction des défenses comportementales chez les pucerons porteurs. Cette diminution de l'expression des comportements défensifs favorise à la fois le puceron et son symbiote car elle réduit les coûts associés à ces comportements. Enfin, une évolution expérimentale sur des populations de parasitoïdes soumises à des populations d'hôtes portant H. defensa (résistantes) ou non (sensibles) montre une adaptation des parasitoïdes soumis aux hôtes résistants. Cette adaptation s'accompagne d'une réduction de la variabilité génétique dans les populations exposées à la résistance. On observe également une divergence génétique entre les populations exposées ou non à la résistance conférée par le symbiote, H. defensa. Cette expérimentation met en évidence le potentiel évolutif des populations d'A. ervi et donc leurs capacités d'adaptation face à des pucerons résistants. Les intérêts fondamentaux et appliqués de ces travaux sont discutés et replacés dans un contexte général.
92

Impact of Cascading Failures on Performance Assessment of Civil Infrastructure Systems

Adachi, Takao 05 March 2007 (has links)
Water distribution systems, electrical power transmission systems, and other civil infrastructure systems are essential to the smooth and stable operation of regional economies. Since the functions of such infrastructure systems often are inter-dependent, the systems sometimes suffer unforeseen functional disruptions. For example, the widespread power outage due to the malfunction of an electric power substation, which occurred in the northeastern United States and parts of Canada in August 2003, interrupted the supply of water to several communities, leading to inconvenience and economic losses. The sequence of such failures leading to widespread outages is referred to as a cascading failure. Assessing the vulnerability of communities to natural and man-made hazards should take the possibility of such failures into account. In seismic risk assessment, the risk to a facility or a building is generally specified by one of two basic approaches: through a probabilistic seismic hazard analysis (PSHA) and a stipulated scenario earthquake (SE). A PSHA has been widely accepted as a basis for design and evaluation of individual buildings, bridges and other facilities. However, the vulnerability assessment of distributed infrastructure facilities requires a model of spatial intensity of earthquake ground motion. Since the ground motions from a PSHA represent an aggregation of earthquakes, they cannot model the spatial variation in intensity. On the other hand, when a SE-based analysis is used, the spatial correlation of seismic intensities must be properly evaluated. This study presents a new methodology for evaluating the functionality of an infrastructure system situated in a region of moderate seismicity considering functional interactions among the systems in the network, cascading failure, and spatial correlation of ground motion. The functional interactions among facilities in the systems are modeled by fault trees, and the impact of cascading failures on serviceability of a networked system is computed by a procedure from the field of operations research known as a shortest path algorithm. The upper and lower bound solutions to spatial correlation of seismic intensities over a region are obtained.
93

Subsystemmethodik für die Auslegung des niederfrequenten Schwingungskomforts von PKW

Angrick, Christian 14 August 2017 (has links)
Um eine zielgerichtete Ableitung von Fahrzeugeigenschaften in frühen Entwicklungsphasen zu ermöglichen, ist eine Subsystemebene erforderlich, die eine konzeptunabhängige Auslegung des Gesamtfahrzeugverhaltens zulässt. In der vorliegenden Arbeit wird daher eine neue Methodik zur Auslegung von Fahrkomfort-Kennwerten auf Basis von Subsystemeigenschaften vorgestellt. Neben der Entwicklung eines geeigneten Modellansatzes, in dem die Subsysteme des Gesamtfahrzeugs durch Greybox-Modelle ohne Komponentenbezug miteinander verknüpft werden, stehen dabei auch dessen Parametrierung sowie die Integration der Methodik im Entwicklungsprozess im Vordergrund. Zur Ableitung der damit verbundenen physikalisch-mechanischen Zusammenhänge werden statische und dynamische Achsprüfstände sowie Simulationen eingesetzt. Die Anwendung der Methodik lässt eine gezielte Eigenschaftsableitung zwischen Gesamtfahrzeug-, Subsystem- und Komponentenebene im Fahrkomfort zu, bei der die Subsystemebene als neue Referenz für die Ableitung von Komponenteneigenschaften dient. Weiterhin erlaubt das Vorgehen eine eigenschaftsbasierte Vorauswahl optimaler Komponentenkonzepte sowie detaillierte Wettbewerbsanalysen. Dadurch wird eine nachhaltige Steigerung der Effizienz im Entwicklungsprozess des Fahrkomforts ermöglicht.
94

Efficient analysis and design of devices in Substrate Integrated Waveguide (SIW) technology

Díaz Caballero, Elena 20 December 2013 (has links)
Para abordar el análisis de estas estructuras de forma altamente eficiente, se pretenden utilizar dos enfoques distintos, que llevarían a dos técnicas distintas y eficientes, pero cada una de ellas con sus ventajas e inconvenientes respecto de la otra, que podremos concluir una vez finalizado el trabajo de investigación. Por un lado, se pretende utilizar el Método de los Momentos, una técnica numérica que convierte las ecuaciones integrales de un problema electromagnético en un sistema linear, expandiendo la magnitud desconocida usando un conjunto de funciones con coeficientes desconocidos. Al forzar las condiciones de contorno, en este caso de potencial eléctrico, en un determinado número de puntos, se obtiene un sistema linear de ecuaciones que será resuelto numéricamente. Por otro lado, según el segundo enfoque, pretende utilizar una expansión en modos cilíndricos del campo, tanto incidente como dispersado. Dada la geometría circular de las vías éstas pueden ser caracterizadas de forma analítica mediante espectros circulares. Posteriormente se resolverá el acoplo entre las vías mediante el método de [1] pero generalizado al caso de objetos inmersos en un medio dieléctrico infinito, y se desarrollará un nuevo método de acoplo modal entre modos cilíndricos y modos guiados proyectando las ecuaciones del acoplo modal tanto sobre modos cilíndricos como sobre modos guiados para evitar las singularidades que aparecen con el método de de [2] cuando los planos de referencia están muy próximos al objeto dispersor. Por tanto, esta técnica caracterizará las vías de forma analítica y resolverá las integrales del acoplo de modos mediante la transformada rápida de Fourier. Para aumentar más aún la eficiencia de ambos métodos se evitará repetir los cálculos para cada punto en frecuencia, y se implementará la técnica de barrido rápido en frecuencia similar descrita en [3], adaptándola al caso particular de cada método de análisis, aunque se prevé que quizá dicho procedimiento sea más difícil de implementar en el segundo método. Se espera que ambas técnicas puedan proporcionar unos tiempos de computación inferiores a los del software comercial de análisis electromagnético más habitual (i.e. HFSS), y también inferiores a otros métodos de análisis recientemente aparecidos en la bibliografía técnica ([4],[5],[6]). En concreto, se espera que los tiempos de computación para barrido discreto en frecuencia sea inferior con el segundo método ya que usa únicamente expresiones analíticas y transformada rápida de Fourier, pero, dado que el primer método es más susceptible de realizar barrido rápido en frecuencia, éste puede ser muy útil a la hora de realizar muchos análisis consecutivos. Una vez se disponga de métodos eficientes para el análisis de dispositivos SIW, se abordará el diseño de varios dispositivos pasivos en esta tecnología (filtros de diferentes topologías, diplexores, multiplexores, híbridos, acopladores, etc.). Como se dispone de una vasta experiencia en el grupo de investigación en el diseño de dispositivos en guía de onda rectangular, se puede como primera aproximación realizar el diseño en guía, y luego transformar esta estructura guiada en otra en tecnología SIW mediante unas reglas empíricas que relacionan ambas tecnologías [7]. Posteriormente se debe ajustar el diseño en el dispositivo SIW ya que estas reglas empíricas no consiguen que la respuesta sea idéntica a la del dispositivo guiado original, principalmente debido al hecho de que los irises rectangulares de la guía son transformados en vías metalizadas con geometría circular, no rectangular. Para minimizar este ajuste, se diseñará el dispositivo guiado con irises con esquinas redondeadas en la cavidad (método de [8] pero con un simulador más eficiente [9]), haciendo que el radio de esas esquinas redondeadas coincida con el de las vías metalizadas que se van a utilizar en el dispositivo SIW. Esto permitirá [...] (Ver documento anexo) / Díaz Caballero, E. (2013). Efficient analysis and design of devices in Substrate Integrated Waveguide (SIW) technology [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34627
95

Probabilistic Multidisciplinary Design Optimization on a high-pressure sandwich wall in a rocket engine application

Wahlström, Dennis January 2017 (has links)
A need to find better achievement has always been required in the space industrythrough time. Advanced technologies are provided to accomplish goals for humanityfor space explorer and space missions, to apprehend answers and widen knowledges. These are the goals of improvement, and in this thesis, is to strive and demandto understand and improve the mass of a space nozzle, utilized in an upperstage of space mission, with an expander cycle engine. The study is carried out by creating design of experiment using Latin HypercubeSampling (LHS) with a consideration to number of design and simulation expense.A surrogate model based optimization with Multidisciplinary Design Optimization(MDO) method for two different approaches, Analytical Target Cascading (ATC) and Multidisciplinary Feasible (MDF) are used for comparison and emend the conclusion. In the optimization, three different limitations are being investigated, designspace limit, industrial limit and industrial limit with tolerance. Optimized results have shown an incompatibility between two optimization approaches, ATC and MDF which are expected to be similar, but for the two limitations, design space limit and industrial limit appear to be less agreeable. The ATC formalist in this case dictates by the main objective, where the children/subproblems only focus to find a solution that satisfies the main objective and its constraint. For the MDF, the main objective function is described as a single function and solved subject to all the constraints. Furthermore, the problem is not divided into subproblems as in the ATC. Surrogate model based optimization, its solution influences by the accuracy ofthe model, and this is being investigated with another DoE. A DoE of the full factorial analysis is created and selected to study in a region near the optimal solution.In such region, the result has evidently shown to be quite accurate for almost allthe surrogate models, except for max temperature, damage and strain at the hottestregion, with the largest common impact on inner wall thickness of the space nozzle. Results of the new structure of the space nozzle have shown an improvement of mass by ≈ 50%, ≈ 15% and ≈ -4%, for the three different limitations, design spacelimit, industrial limit and industrial limit with tolerance, relative to a reference value,and ≈ 10%, ≈ 35% and ≈ 25% cheaper to manufacture accordingly to the defined producibility model.
96

Správa vývojové dokumentace přes WWW II / Administration of development documetation over WWW II

Gregárek, Ondřej January 2008 (has links)
Document server is a web application controllable by way of web browser. It is meant to serve for the management of development documentation. The application is divided to the four basic parts: Requirements, Products, Tests and Test Run. The section Requirements serves for inserting requirements for products. Product is produced on the basis of these needs and registered in part Products. Test setting is created in the part Tests according to requirements from the part Requirements. Particular products are then tested. The part Test Run registers records of these tests. These are parts of the application: management of users, connecting supplements to records, printing and exportation of data to different formats, saving history of records, filtration and sorting of entries, etc. All the data is saved in the database MySQL. The application is written in scripting language PHP. Data is presented by template system Smarty. The output is in language XHTML. Cascading style CSS is used to formatting. This work describes development of the application. First it is dealing with the proposal of the database, connection and structure of particular tables. The function of the programme is explained in detail at the same time, which is essential for the correct proposal of the database. The application is based on the database. The selected structure of files and relations of scripts to library functions are shown. The template system and the interface for access of the programme to the database are explained. The most attention is paid to the description of solving important functions of the application, i.e. listing of records, their pagination, filtration, sorting and operation with them: saving, browsing, copying, confirmation and work with history, category and problems by upkeep of consistent tree and export of data to various formats. It is always outlined the problem, the idea of solving and the description of appropriate scripts. Samples of source code are also included for better understanding of complicated algorithms.
97

Web applications using the Google Web Toolkit / Webanwendungen unter Verwendung des Google Web Toolkits

von Wenckstern, Michael 04 June 2013 (has links) (PDF)
This diploma thesis describes how to create or convert traditional Java programs to desktop-like rich internet applications with the Google Web Toolkit. The Google Web Toolkit is an open source development environment, which translates Java code to browser and device independent HTML and JavaScript. Most of the GWT framework parts, including the Java to JavaScript compiler as well as important security issues of websites will be introduced. The famous Agricola board game will be implemented in the Model-View-Presenter pattern to show that complex user interfaces can be created with the Google Web Toolkit. The Google Web Toolkit framework will be compared with the JavaServer Faces one to find out which toolkit is the right one for the next web project. / Diese Diplomarbeit beschreibt die Erzeugung desktopähnlicher Anwendungen mit dem Google Web Toolkit und die Umwandlung klassischer Java-Programme in diese. Das Google Web Toolkit ist eine Open-Source-Entwicklungsumgebung, die Java-Code in browserunabhängiges als auch in geräteübergreifendes HTML und JavaScript übersetzt. Vorgestellt wird der Großteil des GWT Frameworks inklusive des Java zu JavaScript-Compilers sowie wichtige Sicherheitsaspekte von Internetseiten. Um zu zeigen, dass auch komplizierte graphische Oberflächen mit dem Google Web Toolkit erzeugt werden können, wird das bekannte Brettspiel Agricola mittels Model-View-Presenter Designmuster implementiert. Zur Ermittlung der richtigen Technologie für das nächste Webprojekt findet ein Vergleich zwischen dem Google Web Toolkit und JavaServer Faces statt.
98

Web applications using the Google Web Toolkit

von Wenckstern, Michael 05 June 2013 (has links)
This diploma thesis describes how to create or convert traditional Java programs to desktop-like rich internet applications with the Google Web Toolkit. The Google Web Toolkit is an open source development environment, which translates Java code to browser and device independent HTML and JavaScript. Most of the GWT framework parts, including the Java to JavaScript compiler as well as important security issues of websites will be introduced. The famous Agricola board game will be implemented in the Model-View-Presenter pattern to show that complex user interfaces can be created with the Google Web Toolkit. The Google Web Toolkit framework will be compared with the JavaServer Faces one to find out which toolkit is the right one for the next web project.:I Abstract II Contents III Acronyms and Glossary III.I Acronyms III.II Glossary IV Credits 1 Introduction 2 Basics 2.1 Development of the World Wide Web 2.2 Hypertext Markup Language 2.3 Cascading Style Sheets 2.4 JavaScript 2.5 Hypertext Markup Language Document Object Model 2.6 Asynchronous JavaScript and XML 3 GWT toolbox and compiler 3.1 GWT in action 3.2 A short overview of the toolkit 3.3 GWT compiler and JSNI 3.3.1 Overview of GWT compiler and JSNI 3.3.2 Deferred binding and bootstrapping process 3.3.3 GWT compiler steps and optimizations 3.4 Java Runtime Environment Emulation 3.5 Widgets and Panels 3.5.1 Overview of GWT Widgets 3.5.2 Event handlers in GWT Widgets 3.5.3 Manipulating browser’s DOM with GWT DOM class 3.5.4 GWT Designer and view optimization using UiBinder 3.6 Remote Procedure Calls 3.6.1 Comparison of Remote Procedure Calls with Remote Method Invocations 3.6.2 GWT’s RPC service and serializable whitelist 3.7 History Management 3.8 Client Bundle 3.8.1 Using ImageResources in the ClientBundle interface 3.8.2 Using CssResources in the ClientBundle interface 4 Model-View-Presenter Architecture 4.1 Comparison of MVP and MVC 4.2 GWT Model-View-Presenter pattern example: Agricola board game 4.3 Extending the Agricola web application with mobile views 4.4 Introducing activities in the Agricola Model-View-Presenter pattern enabling browser history 5 Comparison of the two web frameworks: GWT and JSF 5.1 Definitions of comparison fields 5.2 Comparison in category 1: Nearly completely static sites with a little bit of dynamic content, e.g. news update 5.3 Comparison in category 2: Doing a survey in both technologies 5.4 Comparison in category 3: Creating a forum to show data 5.5 Comparison in category 4: Writing a chat application 5.6 Comparison in category 5: Writing the speed game Snake 5.7 Summary 6 Security 6.1 Download Tomcat 6.2 Dynamic Web Application Project with GWT and Tomcat 6.3 Establish HTTPS connections in Tomcat 6.3.1 Create a pem certificate 6.3.2 Convert pem certificate into a key store object 6.3.3 Configure Tomcat’s XML files to enable HTPPS 6.4 Establish a database connection in Tomcat 6.4.1 Create TomcatGWT user and schema, and add the table countries 6.4.2 Configure Tomcat’s XML files to get access to the database connection 6.4.3 PreparedStatements avoid MySQL injections 6.5 Login mechanism in Tomcat 6.6 SafeHtml 7 Presenting a complex software application written in GWT 8 Conclusions 8.1 Summary 8.2 Future work A Appendix A 1 Configure the Google Web Toolkit framework in Eclipse A 1.1 Install the Java Developer Kit A 1.2 Download Eclipse A 1.3 Install the GWT plugin in Eclipse A 1.4 Create first GWT Java Project A 2 Figures A 3 Listings A 3.1 Source code of the Agricola board game A 3.2 Source code of GWT and JSF comparison A 4 Tables R Lists and References R 1 Lists R 1.1 List of Tables R 1.2 List of Figures R 1.3 List of Listings R 2 References R 2.1 Books R 2.2 Online resources / Diese Diplomarbeit beschreibt die Erzeugung desktopähnlicher Anwendungen mit dem Google Web Toolkit und die Umwandlung klassischer Java-Programme in diese. Das Google Web Toolkit ist eine Open-Source-Entwicklungsumgebung, die Java-Code in browserunabhängiges als auch in geräteübergreifendes HTML und JavaScript übersetzt. Vorgestellt wird der Großteil des GWT Frameworks inklusive des Java zu JavaScript-Compilers sowie wichtige Sicherheitsaspekte von Internetseiten. Um zu zeigen, dass auch komplizierte graphische Oberflächen mit dem Google Web Toolkit erzeugt werden können, wird das bekannte Brettspiel Agricola mittels Model-View-Presenter Designmuster implementiert. Zur Ermittlung der richtigen Technologie für das nächste Webprojekt findet ein Vergleich zwischen dem Google Web Toolkit und JavaServer Faces statt.:I Abstract II Contents III Acronyms and Glossary III.I Acronyms III.II Glossary IV Credits 1 Introduction 2 Basics 2.1 Development of the World Wide Web 2.2 Hypertext Markup Language 2.3 Cascading Style Sheets 2.4 JavaScript 2.5 Hypertext Markup Language Document Object Model 2.6 Asynchronous JavaScript and XML 3 GWT toolbox and compiler 3.1 GWT in action 3.2 A short overview of the toolkit 3.3 GWT compiler and JSNI 3.3.1 Overview of GWT compiler and JSNI 3.3.2 Deferred binding and bootstrapping process 3.3.3 GWT compiler steps and optimizations 3.4 Java Runtime Environment Emulation 3.5 Widgets and Panels 3.5.1 Overview of GWT Widgets 3.5.2 Event handlers in GWT Widgets 3.5.3 Manipulating browser’s DOM with GWT DOM class 3.5.4 GWT Designer and view optimization using UiBinder 3.6 Remote Procedure Calls 3.6.1 Comparison of Remote Procedure Calls with Remote Method Invocations 3.6.2 GWT’s RPC service and serializable whitelist 3.7 History Management 3.8 Client Bundle 3.8.1 Using ImageResources in the ClientBundle interface 3.8.2 Using CssResources in the ClientBundle interface 4 Model-View-Presenter Architecture 4.1 Comparison of MVP and MVC 4.2 GWT Model-View-Presenter pattern example: Agricola board game 4.3 Extending the Agricola web application with mobile views 4.4 Introducing activities in the Agricola Model-View-Presenter pattern enabling browser history 5 Comparison of the two web frameworks: GWT and JSF 5.1 Definitions of comparison fields 5.2 Comparison in category 1: Nearly completely static sites with a little bit of dynamic content, e.g. news update 5.3 Comparison in category 2: Doing a survey in both technologies 5.4 Comparison in category 3: Creating a forum to show data 5.5 Comparison in category 4: Writing a chat application 5.6 Comparison in category 5: Writing the speed game Snake 5.7 Summary 6 Security 6.1 Download Tomcat 6.2 Dynamic Web Application Project with GWT and Tomcat 6.3 Establish HTTPS connections in Tomcat 6.3.1 Create a pem certificate 6.3.2 Convert pem certificate into a key store object 6.3.3 Configure Tomcat’s XML files to enable HTPPS 6.4 Establish a database connection in Tomcat 6.4.1 Create TomcatGWT user and schema, and add the table countries 6.4.2 Configure Tomcat’s XML files to get access to the database connection 6.4.3 PreparedStatements avoid MySQL injections 6.5 Login mechanism in Tomcat 6.6 SafeHtml 7 Presenting a complex software application written in GWT 8 Conclusions 8.1 Summary 8.2 Future work A Appendix A 1 Configure the Google Web Toolkit framework in Eclipse A 1.1 Install the Java Developer Kit A 1.2 Download Eclipse A 1.3 Install the GWT plugin in Eclipse A 1.4 Create first GWT Java Project A 2 Figures A 3 Listings A 3.1 Source code of the Agricola board game A 3.2 Source code of GWT and JSF comparison A 4 Tables R Lists and References R 1 Lists R 1.1 List of Tables R 1.2 List of Figures R 1.3 List of Listings R 2 References R 2.1 Books R 2.2 Online resources

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