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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.
1

Développement d'une méthode de modélisation pour l'évaluation de la performance de stratégies de sécurité incendie / Development of a modeling method for evaluating fire safety strategy performance

Muller, Anne 08 December 2010 (has links)
Aujourd'hui en France, l'évaluation de la performance de stratégies de sécurité à déployer pour mettre un bâtiment en sécurité vis-à-vis de l'incendie repose sur une étude d'ingénierie en sécurité incendie. Cette étude a pour objectif l'estimation du risque incendie pour différentes stratégies, et pour des scénarios d'incendies jugés pertinents. Pour parvenir à cette estimation, le Centre Scientifique et Technique du Bâtiment français (CSTB) a mis au point un outil de simulation appelé SCHEMA-SI. Cet outil utilise des réseaux de Petri prédicat-transition différentiels orientés objets et des simulations de Monte Carlo pour générer de multiples scénarios d'incendie. Ces scénarios sont ensuite utilisés pour évaluer le risque incendie encouru avec une stratégie de sécurité. La stratégie est alors jugée d'autant plus performante que le risque incendie est faible. L'objectif de la thèse consiste à contribuer au développement d'une méthode d'analyse de risque incendie utilisant l'outil de simulation SCHEMA-SI. La réflexion a débuté par la définition de ce que devrait être cette méthode. A ce stade, il est apparu que l'une des difficultés que la méthode doit surmonter est celle de la mise en donnés du problème par un groupe d'acteurs impliqués dans la sécurité incendie du bâtiment étudié. Pour résoudre cette difficulté, une méthode de modélisation spécifique a été construite. Cette méthode, baptisée ISI-Systema, repose sur deux fondements principaux : d'une part, un langage graphique de modélisation permettant au groupe d'acteurs de réfléchir à la mise en données du problème en s'appuyant sur une approche systémique ; d'autre part, une démarche de traduction des modèles graphiques obtenus avec le langage systémique en réseaux de Petri compatibles avec SCHEMA-SI.Enfin, une application pratique de cette méthode de modélisation est proposée. / Nowadays in France, building fire safety strategy performance analysis relies on a fire engineering study. This kind of study aims at calculating fire risk for several strategies and for fire scenarios judged as relevant. In order to achieve risk calculation, the French Scientific and technical Building Center (CSTB) has developed a simulation tool called SCHEMA-SI. This tool is based on object-oriented differentiai predicate-transition Petri nets and on Monte Carlo simulations and is built to generate a large number of fire scenarios. Obtained scenarios are hence used to evaluate fire risk related to the strategy to evaluate. The lower the fire risk is obtained, the more efficient the strategy is considered. This thesis aims at contributing to the development of a SCHEMA-SI based fire risk assessment method. This thesis starts by a definition of what this method should be. At this stage, it appears that one of the difficulties to overcome is the one of the problem definition by a group of fire safety concerned people. In arder to solve this difficulty, a modeling method has been developed. This method, so-called ISI-Systema, relies on two main basements: in on hand, on a graphic modeling language created to allow a group of people to think about the problem definition by using a systemic approach ; on the other hand, on a SCHEMA-SI compatible Petri net - graphic model translation procedure. At last, a case study is proposed.
2

Efficiency indicators for Enterprise Modelling Methods and Enterprise Models

Kaidalova, Iuliia January 2011 (has links)
At the present time, when enterprises have tendency for constant improvements, different tools are used to analyze current state of the business and to introduce organizational changes. Enterprise Modeling is one of these tools. Enterprise modeling can be used for different purposes: to restructure or standardize business processes, to develop business strategy, to capture best practices, etc. Evidently, enterprise models creation is resource-consuming job, since it requires variety of resources, for example labor, time and others. However, resources utilization is always aimed at result achievement, which originates the question of efficiency. There is a need to evaluate efficiency in the area of EM, which starts from defining a set of indicators to be checked. This work presents checklists of efficiency indicators for processes that EM can involve. For this purpose it identifies processes (so-called application areas of EMMs and enterprise models) that EM can involve. All of them are characterized with the help of two concepts: required resources and expected results. Formulated efficiency indicators can be used to analyze efficiency in the area of EM, particularly in application areas of EMMs and enterprise models.
3

Multiagent Systems for Robust IoT Services / 頑健なIoTサービスのためのマルチエージェントシステム

Kemas, Muslim Lhaksmana 23 September 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第20028号 / 情博第623号 / 新制||情||108(附属図書館) / 33124 / 京都大学大学院情報学研究科社会情報学専攻 / (主査)教授 石田 亨, 教授 多々納 裕一, 教授 山本 章博 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
4

Contribuição ao estudo de análise de aterramento impulsivo e em altas frequências associado à avaliação da suportabilidade dos seres humanos com base no método da modelagem por linhas de transmissão (TLM)

Gazzana, Daniel da Silva January 2012 (has links)
Este trabalho fundamenta-se no desenvolvimento e aprimoramento de metodologias para a melhor representação do aterramento elétrico sob uma análise transiente. O estudo concentrase no estabelecimento de contribuições ao estado da arte associadas à análise e modelagem de aterramento impulsivo e em altas frequências. O estudo vincula-se também à avaliação da suportabilidade de seres humanos submetidos a potenciais produzidos na superfície do solo, provenientes da corrente elétrica gerada por um surto atmosférico. A concepção das metodologias propostas baseou-se no uso do Método da Modelagem por Linhas de Transmissão em uma dimensão (TLM-1D). Destacam-se três grandes tópicos da pesquisa. O primeiro concentra-se no desenvolvimento de formulação para a inclusão do fenômeno de ionização do solo ao Método TLM-1D clássico. A formulação desenvolvida tem como característica ser uma técnica generalista, independente das propriedades do meio, dimensões do eletrodo e do surto atmosférico. O segundo foco concentra-se no aprimoramento e desenvolvimento de equacionamento analítico para a estimação de potenciais gerados na superfície do solo, originados pela corrente elétrica estabelecida sobre eletrodo de aterramento. Tal equacionamento tem grande aplicabilidade em conjunto com metodologias numéricas unidimensionais, as quais não são capazes de determinar diretamente os referidos potenciais. Por fim, a realização de estudo de suportabilidade e segurança de seres humanos em contato com eletrodos de aterramento submetidos a surto atmosférico, considerando modelo representativo baseado em circuitos elétricos, consolida o trabalho desenvolvido. / This work is based on the development and improvement of methodologies for the best representation of the electrical grounding under a transient analysis. The study concentrated on establishing contributions to the state of the art related to the analysis and modeling of impulsive and high frequencies grounding systems. The study is also associated to the evaluation of the supportability of human beings submitted to the potentials produced on the soil surface from the electric current generated by a lightning. The conception of the proposed methodology was based on the Transmission Line Modeling Method in one dimension (TLM- 1D). Three major research topics can be highlighted. The first involves the development of a formulation to include the soil ionization phenomenon in the classic TLM-1D algorithm. The developed formulation is a generalist technique, independent of the medium properties, characteristic of the electrode and lightning surge. The second aims at the improvement and development of analytical equations for estimating the generated potential on the soil surface, originated by the electric current calculated in the grounding electrode. Such equationing has great applicability in conjunction with one-dimensional numerical methods which are not able to determine such potential directly. Finally, the achievement of a supportability study and personal safety of humans in contact with the grounding electrodes subjected to a lightning, considering a representative model based on electrical circuits, consolidates the developed work.
5

Estimation of the acute toxicity and prediction of the metabolism site for organic molecules using GALAS methodology / Organinių medžiagų ūmaus toksiškumo ir metabolizmo vietos molekulėje prognozavimas taikant GALAS metodą

Sazonovas, Andrius 27 May 2010 (has links)
The dissertation presents GALAS models for the estimation of the acute toxicity towards two rodent species following different administration routes as well as for the prediction of CYP3A4 and CYP2D6 regioselectivity in the main metabolic reactions mediated by these enzymes (13 individual models in total). All these models feature the ability of the quantitative model Applicability Domain (AD) evaluation via the estimated prediction Reliability Indices (RI). I.e., the obtained models conform to one of the main requirements for the QSAR model acceptance as an alternative research method by the EU regulatory institutions. Evident correlation between prediction reliability and its accuracy allowed classifying each model result into one of several qualitative classes according to RI values. One possible way of utilizing such information, discussed in this study, is compound prioritization before experimental testing potentially resulting in reduction of the number of necessary measurements. As demonstrated the AD of the obtained GALAS models can be easily expanded to cover specific compound classes of researcher interest using ‘in-house’ databases of experimental data. This feature significantly improves the possibilities for the practical application of these models, based on public data, in industry. Especially given the fact that the described improvements in predictions following the addition of similar compounds was instant and required no rebuilding of the baseline models. / Disertacijoje pristatomi GALAS metodika paremti ūmaus toksiškumo dviems graužikų rūšims bei visai eilei skirtingų medžiagos patekimo į organizmą būdų ir CYP3A4 bei CYP2D6 fermentų regioselektyvumo pagrindinėse jų katalizuojamose metabolizmo reakcijose prognozavimo modeliai (iš viso 13 individualių modelių). Visi minimi modeliai kokybiškai išsiskiria iš anksčiau publikuotų savo analogų dėl kiekybinio jų pritaikomumo srities įvertinimo galimybės, kurią suteikia apskaičiuojamos prognozės patikimumo indekso (RI) reikšmės. Tokia savybė yra vienas pagrindinių reikalavimų vertinant bet kokio modelio galimybes tapti ES oficialiai pripažintu alternatyviu tyrimo metodu. Aiški prognozių kokybės priklausomybė nuo jų patikimumo išraiškos taip pat suteikia galimybę modelio rezultatus suskaidyti į kokybines klases pagal apskaičiuotąsias RI reikšmes. Vienas iš tokios informacijos panaudojimo būdų siūlomų disertacijoje yra junginių prioritetizavimas prieš bet kokius eksperimentinius matavimus ir netgi pastarųjų skaičiaus potencialus sumažinimas. Disertacijoje taip pat išnagrinėta galimybė greitai bei efektyviai apmokyti gautuosius GALAS modelius naujais eksperimentiniais duomenimis, išplečiant jų pritaikomumo sritį. Ši esminė savybė radikaliai padidina nagrinėjamųjų modelių, paremtų viešai prieinamų duomenų rinkiniais, realaus praktinio panaudojimo farmacijos pramonėje galimybes.
6

Contribuição ao estudo de análise de aterramento impulsivo e em altas frequências associado à avaliação da suportabilidade dos seres humanos com base no método da modelagem por linhas de transmissão (TLM)

Gazzana, Daniel da Silva January 2012 (has links)
Este trabalho fundamenta-se no desenvolvimento e aprimoramento de metodologias para a melhor representação do aterramento elétrico sob uma análise transiente. O estudo concentrase no estabelecimento de contribuições ao estado da arte associadas à análise e modelagem de aterramento impulsivo e em altas frequências. O estudo vincula-se também à avaliação da suportabilidade de seres humanos submetidos a potenciais produzidos na superfície do solo, provenientes da corrente elétrica gerada por um surto atmosférico. A concepção das metodologias propostas baseou-se no uso do Método da Modelagem por Linhas de Transmissão em uma dimensão (TLM-1D). Destacam-se três grandes tópicos da pesquisa. O primeiro concentra-se no desenvolvimento de formulação para a inclusão do fenômeno de ionização do solo ao Método TLM-1D clássico. A formulação desenvolvida tem como característica ser uma técnica generalista, independente das propriedades do meio, dimensões do eletrodo e do surto atmosférico. O segundo foco concentra-se no aprimoramento e desenvolvimento de equacionamento analítico para a estimação de potenciais gerados na superfície do solo, originados pela corrente elétrica estabelecida sobre eletrodo de aterramento. Tal equacionamento tem grande aplicabilidade em conjunto com metodologias numéricas unidimensionais, as quais não são capazes de determinar diretamente os referidos potenciais. Por fim, a realização de estudo de suportabilidade e segurança de seres humanos em contato com eletrodos de aterramento submetidos a surto atmosférico, considerando modelo representativo baseado em circuitos elétricos, consolida o trabalho desenvolvido. / This work is based on the development and improvement of methodologies for the best representation of the electrical grounding under a transient analysis. The study concentrated on establishing contributions to the state of the art related to the analysis and modeling of impulsive and high frequencies grounding systems. The study is also associated to the evaluation of the supportability of human beings submitted to the potentials produced on the soil surface from the electric current generated by a lightning. The conception of the proposed methodology was based on the Transmission Line Modeling Method in one dimension (TLM- 1D). Three major research topics can be highlighted. The first involves the development of a formulation to include the soil ionization phenomenon in the classic TLM-1D algorithm. The developed formulation is a generalist technique, independent of the medium properties, characteristic of the electrode and lightning surge. The second aims at the improvement and development of analytical equations for estimating the generated potential on the soil surface, originated by the electric current calculated in the grounding electrode. Such equationing has great applicability in conjunction with one-dimensional numerical methods which are not able to determine such potential directly. Finally, the achievement of a supportability study and personal safety of humans in contact with the grounding electrodes subjected to a lightning, considering a representative model based on electrical circuits, consolidates the developed work.
7

Contribuição ao estudo de análise de aterramento impulsivo e em altas frequências associado à avaliação da suportabilidade dos seres humanos com base no método da modelagem por linhas de transmissão (TLM)

Gazzana, Daniel da Silva January 2012 (has links)
Este trabalho fundamenta-se no desenvolvimento e aprimoramento de metodologias para a melhor representação do aterramento elétrico sob uma análise transiente. O estudo concentrase no estabelecimento de contribuições ao estado da arte associadas à análise e modelagem de aterramento impulsivo e em altas frequências. O estudo vincula-se também à avaliação da suportabilidade de seres humanos submetidos a potenciais produzidos na superfície do solo, provenientes da corrente elétrica gerada por um surto atmosférico. A concepção das metodologias propostas baseou-se no uso do Método da Modelagem por Linhas de Transmissão em uma dimensão (TLM-1D). Destacam-se três grandes tópicos da pesquisa. O primeiro concentra-se no desenvolvimento de formulação para a inclusão do fenômeno de ionização do solo ao Método TLM-1D clássico. A formulação desenvolvida tem como característica ser uma técnica generalista, independente das propriedades do meio, dimensões do eletrodo e do surto atmosférico. O segundo foco concentra-se no aprimoramento e desenvolvimento de equacionamento analítico para a estimação de potenciais gerados na superfície do solo, originados pela corrente elétrica estabelecida sobre eletrodo de aterramento. Tal equacionamento tem grande aplicabilidade em conjunto com metodologias numéricas unidimensionais, as quais não são capazes de determinar diretamente os referidos potenciais. Por fim, a realização de estudo de suportabilidade e segurança de seres humanos em contato com eletrodos de aterramento submetidos a surto atmosférico, considerando modelo representativo baseado em circuitos elétricos, consolida o trabalho desenvolvido. / This work is based on the development and improvement of methodologies for the best representation of the electrical grounding under a transient analysis. The study concentrated on establishing contributions to the state of the art related to the analysis and modeling of impulsive and high frequencies grounding systems. The study is also associated to the evaluation of the supportability of human beings submitted to the potentials produced on the soil surface from the electric current generated by a lightning. The conception of the proposed methodology was based on the Transmission Line Modeling Method in one dimension (TLM- 1D). Three major research topics can be highlighted. The first involves the development of a formulation to include the soil ionization phenomenon in the classic TLM-1D algorithm. The developed formulation is a generalist technique, independent of the medium properties, characteristic of the electrode and lightning surge. The second aims at the improvement and development of analytical equations for estimating the generated potential on the soil surface, originated by the electric current calculated in the grounding electrode. Such equationing has great applicability in conjunction with one-dimensional numerical methods which are not able to determine such potential directly. Finally, the achievement of a supportability study and personal safety of humans in contact with the grounding electrodes subjected to a lightning, considering a representative model based on electrical circuits, consolidates the developed work.
8

Instrumentation électronique et diagnostic de modules de puissance à semi-conducteur / Electronics instrumentations for the following ageing process and the diagnostic failure of the power semiconductor device

Nguyen, Tien Anh 18 June 2013 (has links)
Les objectifs de la thèse sont d’élaborer des systèmes d’instrumentation électronique qui permettent une analyse et un diagnostic fins de l’état d’intégrité et du processus de vieillissement des composants de puissance à semi-conducteur. Ces travaux visent à évaluer la variation de la conductivité de la métallisation à l’aide de capteurs à Courant Foucault (CF) mais aussi à estimer l’effet du vieillissement des puces et de leur assemblage sur la distribution de courant dans les puces afin de mieux comprendre les mécanismes de défaillance. Des éprouvettes simplifiées mais également des modules de puissance représentatifs ont été vieillis par les cyclages thermique. Les capteurs développés ont été utilisés afin, d’une part de suivre le vieillissement, mais aussi d’autre part afin de comprendre l’effet de ce vieillissement sur le comportement des puces de puissance. Un banc d’instrumentation dédié a été élaboré et exploité pour la mesure locale de la conductivité électrique par le capteur à courants de Foucault, et l’estimation de la distribution de courants à partir de la mesure de cartographies de champ magnétique par capteurs de champ, ou à partir de la cartographie de la distribution de tension sur la métallisation de source. Ce banc a permis en premier lieu d’évaluer la pertinence et les performances de différents types de capteurs exploitables. Le travail s’est également appuyé sur des techniques de traitement de signal, à la fois pour estimer de manière quantitative les informations de conductivité des métallisations issues des capteurs à courant de Foucault, mais aussi pour l’analyse de la distribution de courant à partir des informations fournies par des capteurs de champ magnétiques. Les modèles utilisés exploitent des techniques de modélisation comportementale (le modèle approché de « transformateur analogique » modélisant capteurs à CF ou bien d’inversion de modèle semi-analytique dans le cas l’estimation de la distribution de courant). Les résultats obtenus à partir de ces modèles nous permettrons, d’une part de mieux comprendre certains mécanismes de défaillance, mais également de proposer une implantation et des structures de capteurs pour le suivi « in situ » de l’intégrité des composants. / This thesis is dedicated to develop electronic instrumentation systems that allow to analyse the ageing process and to make a diagnosis the failure mechanisms of power semiconductor device. The research objectives were to evaluate the electrical conductivity variation of metallization layer using the eddy current technique but also to estimate the ageing effect of the semiconductor dies and their module packaging on the current distribution in the die, to better understand the mechanism failures. The specimens simplified and the power semiconductor modules were aged by thermal cycles. The various sensors have been used (eddy current sensor, Hall sensor), to follow the ageing process, and to understand the ageing effect on the power semiconductor die. The experimental instrumentation system has been developed and used, to realize the non destructive evaluation by the eddy current technique on the metallization layer and to measure the map of magnetic field induced above the die by the magnetic sensor, the potential distribution. In the first time, this system allowed to evaluate the relevance and the performance of different type sensors used for the local measure on the electrical conductivity by eddy current sensors and on the currents distribution by Hall sensors or the potential distribution of the source metallization layer. This work was also supported by the signal processing techniques. To estimate quantitatively the electrical conductivity of metallization layer by the eddy current sensors, a model using the two-winding transformer analogy simulate the electromagnetic interaction between the sensor and the conducting plate. And, the current distribution from the measured data is given by inverting a mesh-free modeling of the induced magnetic field. The results obtained from these models can allow us to firstly understand certain failure mechanisms, but also to propose the integrated circuit with the sensors for monitoring "in situ" the state ageing of power semiconductor device.
9

Méthodes de réduction et de propagation d'incertitudes : application à un modèle de chimie-transport pour la modélisation et la simulation des impacts

Boutahar, Jaouad 30 September 2004 (has links) (PDF)
Dans une modélisation intégrée des impacts, l'objectif est de tester plusieurs scénarios d'entrées de modèle et/ ou d'identifier l'effet de l'incertitude des entrées sur les sorties de modèle. Dans les deux cas, un grand nombre de simulations de modèle sont nécessaires. Cela reste bien évidemment infaisable avec un modèle de Chimie-Transport à cause du temps CPU demandé. Pour surmonter cette difficulté, deux approches ont été étudiées dans cette thèse : La première consiste à construire un modèle réduit. Deux techniques ont été utilisées : la première est la méthode POD (Proper Orthogonal Decomposition) liée au comportement statistique du système. La seconde méthode est une méthode efficace de prétabulation fondée sur la troncature d'un développement multivariables de la relation Entrées/ sorties associé au modèle.<br />La seconde est relative à la réduction du nombre de simulations demandé par la méthode Monte-Carlo classique de propagation d'incertitude. La technique utilisée ici est basée sur une représentation d'une sortie de modèle incertaine comme un développement de polynômes orthonormaux de variables d'entrées. Un autre point clé dans la modélisation intégrée d'impacts est de développer des stratégies de réduction des émissions en calculant des matrices de transfert sur plusieurs années de simulation. Une méthode efficace de calcul de ces matrices a été ainsi développée, notamment en définissant des scénarios "chimiquement" représentatifs.<br />L'ensemble de ces méthodes a été appliqué au modèle POLAIR3D, modèle de Chimie-Transport développé dans le cadre de cette thèse.
10

Development of a Two-Stage Computational Modeling Method for Drinking Water Microbial Ecology Effects on Legionella pneumophila Growth

Hibler, David A. January 2020 (has links)
No description available.

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