Thesis (M.S. in Computer Science)--Naval Postgraduate School, Sept. 2004. / Thesis advisor(s): Don Brutzman, Don McGregor. Includes bibliographical references (p. 159-164). Also available online.

Le télescope spatial James Webb (JWST) est le successeur du télescope spatial Hubble (HST). Il est développé en collaboration par les agences spatiales NASA, ESA et CSA. Le spectrographe proche infrarouge NIRSpec est un instrument du JWST. Le Centre de Recherche Astrophysique de Lyon (CRAL) a développé le logiciel de simulation des performances (IPS) de NIRSpec en vue de l'étude de ses performances et de la préparation de poses synthétiques réalistes. Dans cette thèse, nous vérifions certains algorithmes de l'IPS, en particulier ceux traitant des transformations de coordonnées et de la propagation en optique de Fourier. Nous présentons ensuite une interface simplifiée pour la préparation de " scènes " d'observation et un logiciel de traitement de données permettant d'extraire des spectres à partir de poses synthétiques afin de faciliter l'exploitation des simulations. Nous décrivons comment nous avons construit et validé le modèle de l'instrument par comparaison avec les données de calibration. Pour les transformations de coordonnées, le modèle final est capable de reproduire les mesures avec une précision 3 à 5 fois meilleure que celle requise pour la calibration spectrale. Pour la transmission globale notre précision est de 0-10% dans l'absolu et meilleure que 5% en relatif. Finalement, nous présentons la première simulation d'une observation de type " champ profond spectrographique " et nous explorons comment NIRSpec pourra être utilisé pour observer le transit de planètes extra-solaires. Nous déterminons en particulier la luminosité maximale des étoiles hôtes pouvant être observées et quels peuvent être les rapports signal sur bruit attendus.

Le télescope spatial James Webb (JWST) est le successeur du télescope spatial Hubble (HST). Il est développé en collaboration par les agences spatiales NASA, ESA et CSA. Le spectrographe proche infrarouge NIRSpec est un instrument du JWST. Le Centre de Recherche Astrophysique de Lyon (CRAL) a développé le logiciel de simulation des performances (IPS) de NIRSpec en vue de l’étude de ses performances et de la préparation de poses synthétiques réalistes. Dans cette thèse, nous vérifions certains algorithmes de l’IPS, en particulier ceux traitant des transformations de coordonnées et de la propagation en optique de Fourier. Nous présentons ensuite une interface simplifiée pour la préparation de « scènes » d’observation et un logiciel de traitement de données permettant d’extraire des spectres à partir de poses synthétiques afin de faciliter l’exploitation des simulations. Nous décrivons comment nous avons construit et validé le modèle de l’instrument par comparaison avec les données de calibration. Pour les transformations de coordonnées, le modèle final est capable de reproduire les mesures avec une précision 3 à 5 fois meilleure que celle requise pour la calibration spectrale. Pour la transmission globale notre précision est de 0–10% dans l’absolu et meilleure que 5% en relatif. Finalement, nous présentons la première simulation d’une observation de type « champ profond spectrographique » et nous explorons comment NIRSpec pourra être utilisé pour observer le transit de planètes extra-solaires. Nous déterminons en particulier la luminosité maximale des étoiles hôtes pouvant être observées et quels peuvent être les rapports signal sur bruit attendus. / The James Webb Space Telescope (JWST), a joint project by NASA, ESA, and CSA, is the successor mission to the Hubble Space Telescope. One of the four science instruments on board is the near-infrared spectrograph NIRSpec. To study the instrument performance and to create realistic science exposures, the Centre de Recherche Astrophysique de Lyon (CRAL) developed the Instrument Performance Simulator (IPS) software. Validating the IPS functionality, creating an accurate model of the instrument, and facilitating the preparation and analysis of simulations are key elements for the success of the IPS. In this context, we verified parts of the IPS algorithms, specifically the coordinate transform formalism, and the Fourier propagation module. We also developed additional software tools to simplify the scientific usage, as a target interface to construct observation scenes, and a dedicated data reduction pipeline to extract spectra from exposures. Another part of the PhD work dealt with the assembly of an as-built instrument model, and its verification with measurements from a ground calibration campaign. For coordinate transforms inside the instrument, we achieved an accuracy of 3–5 times better than the required absolute spectral calibration, and we could reproduce the total instrument throughput with an absolute error of 0–10% and a relative error of less than 5%. Finally, we show first realistic on-sky simulations of a deep field spectroscopy scene, and we explored the capabilities of NIRSpec to study exoplanetary transit events. We determined upper brightness limits of observable host stars, and give noise estimations of exemplary transit spectra.

Le travail de recherche présenté dans ce mémoire de thèse est de gérer la variabilité géométrique durant le cycle de vie du produit et ses conséquences sur la performance du produit. Le modèle des déviations géométriques du produit exposé dans ce mémoire permet de modéliser les déviations géométriques générées de l'étape de fabrication à l'étape d'assemblage de son cycle de vie. La méthode de simulation Monte-Carlo est utilisée pour générer une image des produits fabriqués. A partir de ces résultats, les déviations géométriques sont intégrées dans la simulation de la performance du produit afin d'établir la relation entre la performance et les paramètres des sources de variation. Une image de la performance réelle du produit fabriqué est générée par l'utilisation de résultat de simulation des déviations géométriques. Les paramètres de sources de variation influençant la performance du produit sont ensuite identifiés et classifiés par rapport au leur niveau d'impact. La variance de la variation de la performance est établie s'en appuyant sur cette relation. Finalement, la solution de la conception robuste est trouvée par la minimisation de la variance de la performance du produit.

Micro-cogeneration is one of the technologies promoted as a response to the global call for the reduction of carbon emissions. Due to its recent application in the residential sector, the implications of its usage have not yet been fully explored, while at the same time, the available simulation tools are not designed for conducting research that focuses on the study of this technology. This thesis develops a virtual prototyping environment, using a dynamic multi-physics simulation tool. The model based procedure in its current form focuses on ICE based micro-CHP systems. In the process of developing the models, new approaches on general system, engine, heat exchanger, and dwelling thermal modelling are being introduced to cater for the special nature of the subject. The developed software is a unique modular simulation tool platform linking a number of independent energy generation systems, and presents a new approach in the study and design of the multi node distributed energy system (DES) with the option of further development into a real-time residential energy management system capable of reducing fuel consumption and CO2 emissions in the domestic sector. In the final chapters, the developed software is used to simulate various internal combustion engine based micro-CHP configurations in order to conclude on the system design characteristics, as well as the conditions, necessary to achieve a high technical, economic and environmental performance in the UK residential sector with the purpose of making micro- CHP a viable alternative to the conventional means of heat & power supply.

Micro-cogeneration is one of the technologies promoted as a response to the global call for the reduction of carbon emissions. Due to its recent application in the residential sector, the implications of its usage have not yet been fully explored, while at the same time, the available simulation tools are not designed for conducting research that focuses on the study of this technology. This thesis develops a virtual prototyping environment, using a dynamic multi-physics simulation tool. The model based procedure in its current form focuses on ICE based micro-CHP systems. In the process of developing the models, new approaches on general system, engine, heat exchanger, and dwelling thermal modelling are being introduced to cater for the special nature of the subject. The developed software is a unique modular simulation tool platform linking a number of independent energy generation systems, and presents a new approach in the study and design of the multi node distributed energy system (DES) with the option of further development into a real-time residential energy management system capable of reducing fuel consumption and CO2 emissions in the domestic sector. In the final chapters, the developed software is used to simulate various internal combustion engine based micro-CHP configurations in order to conclude on the system design characteristics, as well as the conditions, necessary to achieve a high technical, economic and environmental performance in the UK residential sector with the purpose of making micro- CHP a viable alternative to the conventional means of heat & power supply.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / A Física das Radiações é um ramo da Física que está presente em diversas áreas de estudo e se relaciona ao conceito de espectrometria. Dentre as inúmeras técnicas espectrométricas existentes, destaca-se a espectrometria por fluorescência de raios X. Esta também possui uma gama de variações da qual pode-se dar ênfase a um determinado subconjunto de técnicas. A produção de fluorescência de raios X permite (em certos casos) a análise das propriedades físico-químicas de uma amostra específica, possibilitando a determinação de sua constituiçõa química e abrindo um leque de aplicações. Porém, o estudo experimental pode exigir uma grande carga de trabalho, tanto em termos do aparato físico quanto em relação conhecimento técnico. Assim, a técnica de simulação entra em cena como um caminho viável, entre a teoria e a experimentação. Através do método de Monte Carlo, que se utiliza da manipulação de números aleatórios, a simulação se mostra como uma espécie de alternativa ao trabalho experimental.Ela desenvolve este papel por meio de um processo de modelagem, dentro de um ambiente seguro e livre de riscos. E ainda pode contar com a computação de alto desempenho, de forma a otimizar todo o trabalho por meio da arquitetura distribuída. O objetivo central deste trabalho é a elaboração de um simulador computacional para análise e estudo de sistemas de fluorescência de raios X desenvolvido numa plataforma de computação distribuída de forma nativa com o intuito de gerar dados otimizados. Como resultados deste trabalho, mostra-se a viabilidade da construção do simulador através da linguagem CHARM++, uma linguagem baseada em C++ que incorpora rotinas para processamento distribuído, o valor da metodologia para a modelagem de sistemas e a aplicação desta na construção de um simulador para espectrometria por fluorescência de raios X. O simulador foi construído com a capacidade de reproduzir uma fonte de radiação eletromagnética, amostras complexas e um conjunto de detectores. A modelagem dos detectores incorpora a capacidade de geração de imagens baseadas nas contagens registradas. Para validação do simulador, comparou-se os resultados espectrométricos com os resultados gerados por outro simulador já validado: o MCNP. / Radiation Physics is a branch of Physics that is present in various studying areas and relates to the concept of spectrometry. Among the numerous existing spectrometry techniques, there is the X-ray fluorescence spectrometry. It also has a range of variations which can emphasize a particular subset of techniques. The production of X-ray fluorescence enables (in some cases) the analysis of physical and chemical properties of a given sample, allowing the determination of its chemical constitution and also a range of applications. However, the experimental analysis may require a large workload, both in terms of physical apparatus and in relation to technical knowledge. Thus, the simulation comes into play as a viable path between theory and experiment. Through the Monte Carlo method, which uses the manipulation of random numbers, the simulation is a kind of alternative to the experimental analysis. It develops this role by a modeling process, within a secure environment and risk free. And it can count on high performance computing in order to optimize all the work through the distributed architecture. The aim of this paper is the development of a computational simulator for analysis and studying of X-ray fluorescence systems developed on a communication platform distributed natively, in order to generate optimal data. As results, has been proved the viability of the simulator implementation through the CHARM++ language, a language based on C++ which incorporate procedures to distributed processing, the value of the methodology to system modelling e its application to build a simulator for X-ray fluorescence spectrometry. The simulator was built with the ability to reproduce a eletromagnetic radiation source, complex samples and a set of detectors. The modelling of the detectors embody the ability to yield images based on recorded counts. To validate the simulator, the results were compared with the results provided by other known simulator: MCNP.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / A Física das Radiações é um ramo da Física que está presente em diversas áreas de estudo e se relaciona ao conceito de espectrometria. Dentre as inúmeras técnicas espectrométricas existentes, destaca-se a espectrometria por fluorescência de raios X. Esta também possui uma gama de variações da qual pode-se dar ênfase a um determinado subconjunto de técnicas. A produção de fluorescência de raios X permite (em certos casos) a análise das propriedades físico-químicas de uma amostra específica, possibilitando a determinação de sua constituiçõa química e abrindo um leque de aplicações. Porém, o estudo experimental pode exigir uma grande carga de trabalho, tanto em termos do aparato físico quanto em relação conhecimento técnico. Assim, a técnica de simulação entra em cena como um caminho viável, entre a teoria e a experimentação. Através do método de Monte Carlo, que se utiliza da manipulação de números aleatórios, a simulação se mostra como uma espécie de alternativa ao trabalho experimental.Ela desenvolve este papel por meio de um processo de modelagem, dentro de um ambiente seguro e livre de riscos. E ainda pode contar com a computação de alto desempenho, de forma a otimizar todo o trabalho por meio da arquitetura distribuída. O objetivo central deste trabalho é a elaboração de um simulador computacional para análise e estudo de sistemas de fluorescência de raios X desenvolvido numa plataforma de computação distribuída de forma nativa com o intuito de gerar dados otimizados. Como resultados deste trabalho, mostra-se a viabilidade da construção do simulador através da linguagem CHARM++, uma linguagem baseada em C++ que incorpora rotinas para processamento distribuído, o valor da metodologia para a modelagem de sistemas e a aplicação desta na construção de um simulador para espectrometria por fluorescência de raios X. O simulador foi construído com a capacidade de reproduzir uma fonte de radiação eletromagnética, amostras complexas e um conjunto de detectores. A modelagem dos detectores incorpora a capacidade de geração de imagens baseadas nas contagens registradas. Para validação do simulador, comparou-se os resultados espectrométricos com os resultados gerados por outro simulador já validado: o MCNP. / Radiation Physics is a branch of Physics that is present in various studying areas and relates to the concept of spectrometry. Among the numerous existing spectrometry techniques, there is the X-ray fluorescence spectrometry. It also has a range of variations which can emphasize a particular subset of techniques. The production of X-ray fluorescence enables (in some cases) the analysis of physical and chemical properties of a given sample, allowing the determination of its chemical constitution and also a range of applications. However, the experimental analysis may require a large workload, both in terms of physical apparatus and in relation to technical knowledge. Thus, the simulation comes into play as a viable path between theory and experiment. Through the Monte Carlo method, which uses the manipulation of random numbers, the simulation is a kind of alternative to the experimental analysis. It develops this role by a modeling process, within a secure environment and risk free. And it can count on high performance computing in order to optimize all the work through the distributed architecture. The aim of this paper is the development of a computational simulator for analysis and studying of X-ray fluorescence systems developed on a communication platform distributed natively, in order to generate optimal data. As results, has been proved the viability of the simulator implementation through the CHARM++ language, a language based on C++ which incorporate procedures to distributed processing, the value of the methodology to system modelling e its application to build a simulator for X-ray fluorescence spectrometry. The simulator was built with the ability to reproduce a eletromagnetic radiation source, complex samples and a set of detectors. The modelling of the detectors embody the ability to yield images based on recorded counts. To validate the simulator, the results were compared with the results provided by other known simulator: MCNP.

This thesis examines the impacts of possible climate change on selected buildings. For simulations in program BSim the author uses climatic data of SRES scenarios, specifically models B1, A1B and A2. It also includes a research on global warming, design and optimization of the measurement and control system at the production hall and a part of the energy audit for the office building.

L’intégration de l’environnement et des systèmes d’information progresse très vite depuis 10 ans. Cette intégration permet de suivre des évolutions naturelles, physiques, sociétales ; de les mesurer, de les comprendre ; quelquefois de les contrôler. On peut assimiler cette intégration à des besoins, tels que les changements climatiques ou les économies de ressources ; mais aussi à des progrès technologiques dans les domaines des systèmes miniatures, des communications sans fil et des capteurs.Dans ce contexte, nous avons d’abord effectué un apprentissage technologique, en réalisant plusieurs petits systèmes et des logiciels applicatifs de bas et de haut niveau. Nous nous sommes attaqués à la partie frontale des chaînes logicielles, celle qui permet de passer des bases de données pour Systèmes d’Information Géographique à l’implantation et l’exploitation de systèmes distribués de capteurs. QuickMap est ainsi un logiciel de navigation multi-services, incluant OpenStreetMap, construit pour le placement des capteurs et la spécification de systèmes de cellules physiques.Sur la plateforme NetGen, nous avons réalisé un simulateur concurrent associant un ou plusieurs mobiles à un ou plusieurs champs de capteurs. Une application est l’étude des interactions entre satellite en orbites basses, réseaux de capteurs lointains et stations de contrôle.Le séquencement par le temps permet d’associer plusieurs activités aériennes et au sol, en bénéficiant de hautes performances.Enfin, les questionnements méthodologiques ont amené à considérer la possibilité de virtualisation, à la fois du capteur, en le recouvrant d’une machine virtuelle, et à la fois du système d’observation distribué, en utilisant la plateforme NetGen.Nous avons maquetté un capteur et son interface radio en termes de processus communicants, en cherchant à réduire la complexité et la diversité de la programmation des petits systèmes matériels.Plusieurs de nos réalisations sont effectives et servent à des projets de recherche actifs.Cette thèse a été réalisée à l’Université de Brest, laboratoire Lab-STICC, grâce à une allocation de la communauté brestoise BMO. / The integration of environment and information systems is progressing quickly since 10 years. This allows to monitor natural, physical or societal evolutions; to capture their logic and sometimes to control their effects. This integration is feasible thanks to many technical and scientific progresses: sensors, wireless communications, system on chips, batteries, distributed systems and geo-localization. The benefits are important for climate change monitoring and resource savings.In this context, we have firstly achieved a learning of technologies and several practical system realizations. We have produced a navigation software (QuickMap) allowing to interface gis databases and tile servers similar to OpenStreetMap, taking care of sensor locations and outputs. QuickMap is also a nice frontend to produce cellular systems oriented to physical simulations.Using the NetGen platform, we have produced a simulation framework allowing to schedule mobile moves with sensor field activities. A case study was leo satellites visiting remote sensor systems, with investigations on two algorithms suitable for data collection and control.Finally we have addressed the question of observation system virtualization by using an high level, process oriented virtual machine (tvm) to control the wireless link, a step forward to make the distributed and local behaviours homogeneous in terms of programming and simulation.Many of our developments are currently involved in active projects.This thesis was funded by a grant of Brest Metropole Oceane (BMO) and was achieved in a wireless research group at University of Brest, Lab-STICC laboratory.