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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.
21

Architecture Framework for Trapped-ion Quantum Computer based on Performance Simulation Tool

Ahsan, Muhammad January 2015 (has links)
<p>The challenge of building scalable quantum computer lies in striking appropriate balance between designing a reliable system architecture from large number of faulty computational resources and improving the physical quality of system components. The detailed investigation of performance variation with physics of the components and the system architecture requires adequate performance simulation tool. In this thesis we demonstrate a software tool capable of (1) mapping and scheduling the quantum circuit on a realistic quantum hardware architecture with physical resource constraints, (2) evaluating the performance metrics such as the execution time and the success probability of the algorithm execution, and (3) analyzing the constituents of these metrics and visualizing resource utilization to identify system components which crucially define the overall performance.</p><p>Using this versatile tool, we explore vast design space for modular quantum computer architecture based on trapped ions. We find that while success probability is uniformly determined by the fidelity of physical quantum operation, the execution time is a function of system resources invested at various layers of design hierarchy. At physical level, the number of lasers performing quantum gates, impact the latency of the fault-tolerant circuit blocks execution. When these blocks are used to construct meaningful arithmetic circuit such as quantum adders, the number of ancilla qubits for complicated non-clifford gates and entanglement resources to establish long-distance communication channels, become major performance limiting factors. Next, in order to factorize large integers, these adders are assembled into modular exponentiation circuit comprising bulk of Shor's algorithm. At this stage, the overall scaling of resource-constraint performance with the size of problem, describes the effectiveness of chosen design. By matching the resource investment with the pace of advancement in hardware technology, we find optimal designs for different types of quantum adders. Conclusively, we show that 2,048-bit Shor's algorithm can be reliably executed within the resource budget of 1.5 million qubits.</p> / Dissertation
22

Proposition de scénarios de gestion raisonnée des déchets en vue de leur valorisation énergétique / Establishment of an energy recovery sequence of wastes in Reunion island

Hatik, Christelle 11 December 2015 (has links)
La société de consommation dans laquelle nous évoluons est génératrice de beaucoup de pollutions notamment de déchets. Cette croissance exponentielle de détritus nous amène à reconsidérer nos habitudes de consommation et notre vision du système actuel. C'est dans une réelle prise de conscience des dégâts occasionnés que nous pourrons agir pour améliorer ces failles dans un but optimisation et de performances. C'est pourquoi nous avons choisi d'étudier la gestion des déchets afin de pouvoir répondre à ces objectifs et proposer des scénarios de gestion et de traitement des déchets adaptés aux territoires étudiés. Pour mener à bien cette étude, nous nous sommes intéressés à l'île de la Réunion permettant ainsi à contribuer au développement des territoires insulaires. Autour de cette problématique, nous nous sommes attachés principalement à développer une démarche méthodologique permettant de composer différents scénarios de déchets. Afin de réaliser la création des scénarios, nous avons mis en œuvre un outil de simulation et de modélisation de traitement et de gestion des déchets. Pour cela, nous avons développé une méthode, une approche descriptive qui nous permet de présenter de manière intelligible toutes les entités qui composent le système de traitement des déchets ainsi que les flux de matière et d'énergie qui interfèrent avec les systèmes observés. Nous commençons par une phase d'identification où toutes les entités observées (flux et systèmes) sont clairement définies, nous poursuivons la description par une phase de caractérisation où nous définissons et renseignons tous les paramètres d'observation des flux et des systèmes. Sur cette base, nous avons mis au point un outil de simulation de gestion et de traitement des déchets. La conception de l'outil nécessite donc une connaissance précise des éléments constituant chacun des niveaux d'observation étudiés. Cette observation du système par l'observation des flux nous a permis de mettre en évidence les phases de traitement autour des étapes de stockage, de transport et de transformation. C'est notamment au travers de ces indices qu'il nous a été possible d'identifier les paramètres de gestion à considérer afin de répondre à nos problématiques de coûts et d'environnement. À ce stade, l'outil permet une acquisition de données détaillées à toutes les phases de gestion afin d'établir un certain nombre de scénarii de gestion des déchets. Une fois les scénarios mis en œuvre dans l'outil, une analyse multicritères développée à partir de l'outil de calcul PROMETHEE est réalisée afin permettre le classement des différentes alternatives possibles dans un but d'aide à la décision. Cette analyse s'est avérée pertinente dans le choix des meilleurs scénarios de gestion et de traitement des déchets. Et nous permet de conduire une réflexion la moins orientée possible afin d'assurer une bonne crédibilité des choix et décisions à retenir. / Today's consumer society is generating a lot of pollution and waste . The exponential growth of garbage must lead us to rethink the way we consume and the way we consider the current system. Raising awareness of the damage is the best way to improve the situation so as to achieve better and more efficient results. That is why we chose to study waste management, to answer these objectives and to establish waste management scenarios adapted to a specific territory, here Reunion Island. Thereby, this study will contribute to the general development of insular territories. For the study, we have implemented a methodology allowing us to build waste management scenarios. To create these, we have developed a simulation and modelization tool for waste treatment and waste management. The methodology is organized in two parts: i) A description phase and ii) A quantification phase for each scenario of waste management. i) The description phase enables us to know and classify all the entities that compose the waste treatment system as well as raw flow and energy flow. For this, each part of a scenario can be divided into elementary components to simplify their creation. ii) The quantification phase is operational once all flows and entities are identified. This phase consists in defining and quantify all the parameters (flows and entities).Afterwards, we have developed a simulation and modelization tool for waste treatment and waste management to create scenarios. Each scenario requires environmental, economic and social parameters. At this stage, we can collect data for all management phases and establish a panel of scenarios. After scenarios are integrated in the tool, we can do a multi-criteria analysis to classify all possible alternatives that will help decision making. This analysis has proved relevant for choosing the best management and waste treatment scenarios. It also allows us to conduct a study that is as little oriented as possible, so as to ensure the reliability of the choices and decisions that will be selected.
23

Análise do uso da luz natural em salas de aula : estudo de caso em Aracaju - SE / Investigating the use of daylight in classrooms : a case study in Aracaju - SE

Dias, Amanda Fontes Aragão 28 March 2011 (has links)
The use of daylight brings many advantages, as a better quality lighting, psychophysiological benefits and the outside view. In addition, it minimizes the use of artificial lighting and it contributes to the recent interest in energy efficiency. But, despite the daylight s availability existing in Brazil, especially in its Northeast, and despite the great number of daylighting simulation tools, the concern with its optimization hardly takes part on the inicial design of buidings. This thesis is embedded within this context and it aims to analyze and compare the lighting performance between classrooms, trying to support daylighting in these environments. With the TropLux, the simulation of a standard classroom in the city of Aracaju, state of Sergipe, designated Geometry 1, the simulation of some changes in its characteristics, designated Geometries 2 and 3, and the simulation of new geometries with daylighting systems, designated Geometries 4 and 5, were proceeded. In both cases, the CIE Sky types 1 (overcast), 10 (partly cloudy) and 14 (clear) were considered. To analyze the lighting performance of these geometries, it was created isocurves graphics with percentages of illuminances inside the interval 300 lx < E < 2000 lx. From these isocurves graphics, different behaviours of the geometries under the Sky types analyzed were observed. To compare its performances, the average of illuminance s average, the average of the illuminance s percentages inside the interval above and the maximum and minimum values of the illuminance s average were calculated. These values evidence that isolated interventions in the standard classroom (Geometry 1), like increasing the ceiling reflectance (Geometry 2) or adopting a dropped ceiling plan (Geometry 3), does not contribute with the lighting performance s improvement in the illuminance`s interval considered. Nevertheless, they evidence na evolution in the lighting performance of Geometry 5 in relation to the standard classroom (Geometry 1). / O uso da luz natural traz diversas vantagens, dentre as quais destacam-se uma melhor qualidade da iluminação, benefícios psicofisiológicos e o contato com o meio exterior. Além disso, reduz o uso dos sistemas de iluminação artificial, contribuindo com o recente interesse pela eficiência energética. Mas, apesar da disponibilidade de luz natural existente no Brasil, especialmente na sua região Nordeste, e da existência de ferramentas de simulação computacional da luz natural, a preocupação com a sua otimização dificilmente faz parte da fase inicial de projeto das edificações. É dentro desse contexto que o presente trabalho está inserido, com o objetivo de analisar e comparar o desempenho luminoso entre salas de aula, tentando favorecer o uso da luz natural nesses ambientes. Utilizando-se o TropLux, procedeu-se à simulação de uma sala de aula padrão da cidade de Aracaju, no estado de Sergipe, designada Geometria 1, e de duas salas com alterações de algumas de suas características, designadas Geometrias 2 e 3, além de duas novas geometrias contendo elementos de controle e redirecionamento da luz natural, designadas Geometrias 4 e 5. Em ambos os casos foram considerados os céus CIE 1 (encoberto), 10 (parcialmente encoberto) e 14 (claro). Para a análise do desempenho luminoso das geometrias foram gerados gráficos de isocurvas contendo os percentuais de iluminâncias dentro do intervalo 300 lx < E < 2000 lx. A partir deles, observou-se os diferentes comportamentos das geometrias sob os tipos de céu analisados. Para a comparação entre os seus desempenhos, foram calculadas a média das iluminâncias médias, a média dos percentuais de iluminâncias dentro do intervalo proposto e os valores máximo e mínimo das iluminâncias médias. Tais valores demonstram que intervenções isoladas na sala de aula em estudo (Geometria 1), como o aumento da refletância do teto (Geometria 2) ou a inclusão de um teto rebaixado plano (Geometria 3), não trazem melhorias em relação ao seu desempenho luminoso dentro do intervalo de iluminâncias considerado. Apesar disso, sugerem uma evolução no desempenho luminoso da Geometria 5 em relação à sala de aula em estudo (Geometria 1).
24

Système intégré de rafraîchissement d’air pour le bâtiment à base de matériaux à changement de phase / Air-cooling integrated system in building using phase change material

Rouault, Fabien 10 April 2014 (has links)
Les systèmes de rafraîchissement d'air basés sur des échangeur-stockeurs composés de Matériaux à Changement de Phase (MCP) sont une alternative possible aux systèmes de climatisation pour le confort d'été dans les bâtiments. Toutefois, les performances de tels systèmes de rafraîchissement sont étroitement liées aux conditions climatiques et aux configurations des bâtiments à rafraîchir. L'objectif de ce travail de thèse est de développer un outil d'aide à la conception permettant un pré-dimensionnement optimal de systèmes de rafraîchissement d'air utilisant des MCP dès le stade de la conception préliminaire. Un modèle thermique dynamique simulant le comportement d'un échangeur-stockeur air/MCP est donc développé puis couplé à une plateforme logicielle de simulation thermique dynamique du bâtiment. Les modèles d'échangeur-stockeurs et de co-simulation sont validés à l'aide d'expériences menées sur deux prototypes d'échangeur-stockeur et la plateforme expérimentale de maison à énergie positive NAPEVOMO. Enfin un premier outil d'aide à la conception utilisant un algorithme d'optimisation est développé pour définir une configuration optimale de système maintenant le confort estival dans la maison NAPEVOMO. / Air-cooling systems using latent heat thermal energy storage (LHTES) are potential alternatives to air-conditioners for summer climate control in buildings. However, the performances of such systems are tightly linked to weather conditions and the configuration of the building to be cooled. The aim of this doctoral work is to develop a design support tool allowing optimally dimensioning an air-cooling system using phase change material at the preliminary design stage. A dynamic thermal model, simulating the behaviour an LHTES device exchanging with air, is developed and coupled with a building performance program. The LHTES and the co-simulation models are validated by comparison with experiments carried out on two prototypes of LHTES device and the experimental platform of zero energy building NAPEVOMO. Finally, a first design support tool using genetic algorithm is developed to define the optimal configuration of an air-cooling system for the summer comfort in « NAPEVOMO » house.
25

Driver model for a software in the loop simulation tool / En förarmodell för ”software in the loop” simuleringsverktyg

Zheng, Yue January 2019 (has links)
For this project, a Software-In-the-Loop (SIL) simulation tool is used at Scania (“VTAB” – Virtual Truck and Bus), which simulates the submodels of the mechanical vehicle components together with the real control units. The simulation tool contains the following submodels: Engine model, Drivetrain model, Drive cycle model, Restbus model, and Driver model. The simulated human driver submodel in the restbus model outputs two pedal control signals to the control unit, namely the gas and brake pedals. With these two pedal signals, the control unit decides the modes of mechanical vehicle components. This driver model needs to be reworked to obtain a better velocity following performance. Two controllers, fuzzy PI anti-windup and backward calculation, are implemented in the driver model and compared by the velocity tracking accuracy and the pedal switching frequency. In the comparison and analysis section, two different cycles and two weights of payload are simulated. The simulation results demonstrate that both controllers can improve the driver model’s velocity tracing accuracy. Further, the fuzzy PI anti-windup controller is better when considering pedal signals fluctuation frequency and implementation complexity. / För detta projekt används ett simuleringsverktyg Software-In-the-Loop (SIL) på Scania (“VTAB” - Virtual Truck and Bus), vilket simulerar submodellerna för de mekaniska fordonskomponenterna tillsammans med de verkliga styrenheterna. Simuleringsverktyget innehåller följande submodeller: Motormodell, Drivmotormodell, Drivcykelmodell, Restbusmodell och Drivermodell. Den simulerade submodellen för mänsklig förare i restbussmodellen kommer att sända två pedalsstyrsignaler till styrenheten, nämligen gas och broms. Med dessa två pedalsignaler kan styrenheten avgöra lägen av mekaniska fordonskomponenter. Denna drivrutinmodell måste omarbetas för att få en bättre hastighetsspårnings presentationsförmåga. Två styrenheter, fuzzy PI anti-windup och bakåtberäkning, implementeras i förarmodell och jämförs respektive med hastighetsspårningsnoggrannhet och pedalväxelfrekvens. I jämförelseoch analysavsnittet simuleras två olika cyklar och två nyttolast. Simuleringsresultaten visar att båda kontrollerna kan förbättra förarmodellens hastighetsspårningskapacitet. Vidare är fuzzy PI-anti-windup-kontroller bättre när man tar hänsyn till pedalsignalernas fluktueringsfrekvens och implementeringskomplexitet
26

An Appraisal Of The Supernova Minicomputer As A Process Simulation Tool

Foran, Charles 01 1900 (has links)
<p> The object of this work was to evaluate the Supernova ninicomputer as a process simulation tool. To accomplish this obje c tive the GEMCS ste2dy-state simulation system wa.s programmed for the Supernova. This system was programmed to run in five different modes, BASIC , two modes which require that al.L progra1ns are written in Assembly Language, and two modes in which programs may be called from the disk. Of these latter two modes, one requires all programs to be written in Assembly Language; the other mode allows programs to be written in Assembly Language or FORTRAN IV. </p> <p> Two case studies which had previously been run on the CDC 6400 were run on the Supernova to test and evaluate f our of the modes in which GEMCS was proerammed for the Supernova. </p> <p> The studies have also provided an a ssessment of the hardware and softws.re facilities of the Supernova and the results of thjs assessment were documented. In addition the opera tion of the various strategies used to impl ement GEMCS have provided an indication of the feasibility of the impl ementation of the dynamic system simulation program, DYNSYS. </p> / Thesis / Doctor of Philosophy (PhD)
27

A Simulation Platform to Demonstrate Active Demand-Side Management by Incorporating Heuristic Optimization for Home Energy Management

Gudi, Nikhil 09 September 2010 (has links)
No description available.
28

Contributions to the Use of Statistical Methods for Improving Continuous Production

Capaci, Francesca January 2017 (has links)
Complexity of production processes, high computing capabilities, and massive datasets characterize today’s manufacturing environments, such as those of continuous andbatch production industries. Continuous production has spread gradually acrossdifferent industries, covering a significant part of today’s production. Commonconsumer goods such as food, drugs, and cosmetics, and industrial goods such as iron,chemicals, oil, and ore come from continuous processes. To stay competitive intoday’s market requires constant process improvements in terms of both effectivenessand efficiency. Statistical process control (SPC) and design of experiments (DoE)techniques can play an important role in this improvement strategy. SPC attempts toreduce process variation by eliminating assignable causes, while DoE is used toimprove products and processes by systematic experimentation and analysis. However,special issues emerge when applying these methods in continuous process settings.Highly automated and computerized processes provide an exorbitant amount ofserially dependent and cross-correlated data, which may be difficult to analyzesimultaneously. Time series data, transition times, and closed-loop operation areexamples of additional challenges that the analyst faces.The overall objective of this thesis is to contribute to using of statisticalmethods, namely SPC and DoE methods, to improve continuous production.Specifically, this research serves two aims: [1] to explore, identify, and outlinepotential challenges when applying SPC and DoE in continuous processes, and [2] topropose simulation tools and new or adapted methods to overcome the identifiedchallenges.The results are summarized in three appended papers. Through a literaturereview, Paper A outlines SPC and DoE implementation challenges for managers,researchers, and practitioners. For example, problems due to process transitions, themultivariate nature of data, serial correlation, and the presence of engineering processcontrol (EPC) are discussed. Paper B further explores one of the DoE challengesidentified in Paper A. Specifically, Paper B describes issues and potential strategieswhen designing and analyzing experiments in processes operating under closed-loopcontrol. Two simulated examples in the Tennessee Eastman (TE) process simulatorshow the benefits of using DoE techniques to improve and optimize such industrialprocesses. Finally, Paper C provides guidelines, using flow charts, on how to use thecontinuous process simulator, “The revised TE process simulator,” run with adecentralized control strategy as a test bed for developing SPC and DoE methods incontinuous processes. Simulated SPC and DoE examples are also discussed.
29

Impact of Wind Farm Control Technologies on Wind Turbine Reliability

Walgern, Julia January 2019 (has links)
Cost efficient operation and maintenance strategies are crucial for reducing cost of wind energy. Since the regime change from feed-in tariffs to an auction-based bidding system for capacity in most European wind projects, levelized cost of energy is challenged constantly. Therefore, new technologies such as new controllers are developed to improve operation and to increase profit. Previous research studies demonstrated the advantage of increased power output of wake redirection control. However, understanding and quantifying the impact of wind farm control technologies on operation and maintenance strategies is inevitable to evaluate the economic feasibility of such new technologies. Thus, an event-based O&amp;M simulation tool has been developed. Besides general modules, such as the wind turbine model, the weather forecasting model and a model for simulating corrective and planned maintenance, the developed tool also takes wake effects into account. This allows considering different power productions for each individual turbine and a failure rate distribution within the wind farm which is based on altering loads on the different components. Both aspects are driven by changes in operation when applying a new controller technology. Exemplarily, the economic feasibility of a closed-loop active wake steering control has been analysed. Main achievements of this study are the possibility to quantify the impact of the active wake steering control on O&amp;M related KPIs. Results show that additional loads caused by applying yaw-misalignment and redirecting wake, lead to an increase in OPEX. However, the achieved energy production gain and thus related additional revenue exceeds additional cost in the case study. Nonetheless, the study reveals that the profitability of the controller is highly dependent on the electricity price which can be acquired during the wind farm’s lifetime.
30

Modélisation dynamique des apports thermiques dus aux appareils électriques en vue d'une meilleure gestion de l'énergie au sein de bâtiments à basse consommation / Dynamic Thermal Modeling of Electrical Appliances for Energy Management of Low Energy Buildings

Park, Herie 15 May 2013 (has links)
Ce travail propose un modèle thermique dynamique des appareils électriques dans les bâtiments basse consommation. L'objectif de ce travail est d'étudier l'influence des gains thermiques de ces appareils sur le bâtiment. Cette étude insiste sur la nécessité d'établir un modèle thermique dynamique des appareils électriques pour une meilleure gestion de l'énergie du bâtiment et le confort thermique de ses habitants.Comme il existe des interactions thermiques entre le bâtiment et les appareils électriques, sources de chaleur internes au bâtiment, il est nécessaire de modéliser le bâtiment. Le bâtiment basse consommation est modélisé dans un premier temps par un modèle simple reposantl'étude d'une pièce quasi-adiabatique. Ensuite, dans le but d'établir le modèle des appareils électriques, ceux-ci sont classés en quatre catégories selon leurs propriétés thermiques et électriques. A partir de cette classification et du premier principe de la thermodynamique, un modèle physique générique est établi. Le protocole expérimental et la procédure d'identification des paramètres thermiques des appareils sont ensuite présentés. Afin d'analyser la pertinence du modèle générique appliqué à des cas pratiques, plusieurs appareils électriques utilisés fréquemment dans les résidences – un écran, un ordinateur, un réfrigérateur, un radiateur électrique à convection et un micro-onde – sont choisis pour étudier et valider ce modèle ainsi que les protocoles d'expérimentation et d'identification. Enfin, le modèle proposé est intégré dans le modèle d'un bâtiment résidentiel développé et validé par le CSTB. Ce modèle couplé des appareils et du bâtiment est implémenté dans SIMBAD, un outil de simulation du bâtiment. A travers cette simulation, le comportement thermique du bâtiment et la quantité d'énergie nécessaire à son chauffage sur une période hivernale, ainsi que l'inconfort thermique dû aux appareils électriques durant l'été, sont observés.Ce travail fournit des résultats quantitatifs de l'effet thermique de différents appareils électriques caractérisés dans un bâtiment basse consommation et permet d'observer leur dynamique thermique et leurs interactions. Finalement, cette étude apporte une contribution aux études de gestion de l'énergie des bâtiments à basse consommation énergétique et du confort thermique des habitants. / This work proposes a dynamic thermal model of electrical appliances within low energy buildings. It aims to evaluate the influence of thermal gains of these appliances on the buildings and persuades the necessity of dynamic thermal modeling of electrical appliances for the energy management of low energy buildings and the thermal comfort of inhabitants.Since electrical appliances are one of the free internal heat sources of a building, the building which thermally interact with the appliances has to be modeled. Accordingly, a test room which represents a small scale laboratory set-up of a low energy building is first modeled based on the first thermodynamics principle and the thermal-electrical analogy. Then, in order to establish the thermal modeling of electrical appliances, the appliances are classified into four categories from thermal and electrical points of view. After that, a generic physically driven thermal model of the appliances is derived. It is established based also on the first thermodynamics principle. Along with this modeling, the used experimental protocol and the used identification procedure are presented to estimate the thermal parameters of the appliances. In order to analyze the relevance of the proposed generic model applied to practical cases, several electrical appliances which are widely used in residential buildings, namely a monitor, a computer, a refrigerator, a portable electric convection heater, and microwave are chosen to study and validate the proposed generic model and the measurement and identification protocols. Finally, the proposed dynamic thermal model of electrical appliances is integrated into a residential building model which was developed and validated by the French Technical Research Center for Building (CSTB) on a real building. This coupled model of the appliances and the building is implemented in a building energy simulation tool SIMBAD, which is a specific toolbox of Matlab/Simulink®. Through the simulation, thermal behavior and heating energy use of the building are observed during a winter period. In addition, thermal discomfort owing to usages of electrical appliances during a summer period is also studied and quantified.This work therefore provides the quantitative results of thermal effect of differently characterized electrical appliances within a low energy building and leads to observe their thermal dynamics and interactions. Consequently, it permits the energy management of low energy buildings and the thermal comfort of inhabitants in accordance with the usages of electrical appliances.

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