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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

Uživatelské měřicí moduly pro platformu cRIO / User-defined Measurement Modules for cRIO

Pivnička, Martin January 2015 (has links)
This thesis describes design and manufacture of measuring and communication modules for CompactRIO platform. In the first section is described platform from National Instrument suitable for measurement and control technology. There is written more fact about CompactRIO. The second part is focused on description of the hardware requirements needed to construct the module, communication and working modes. The third part describes information about support programs. At the end of third part is describes practical application of input digital card. Next section consists of practical proposal modules (input / output analog module, GPS modulu) and achievements.
92

Impact of Device Parametric Tolerances on Current Sharing Behavior of a SiC Half-Bridge Power Module

Watt, Grace R. 22 January 2020 (has links)
This paper describes the design, fabrication, and testing of a 1.2 kV, 6.5 mΩ, half-bridge, SiC MOSFET power module to evaluate the impact of parametric device tolerances on electrical and thermal performance. Paralleling power devices increases current handling capability for the same bus voltage. However, inherent parametric differences among dies leads to unbalanced current sharing causing overstress and overheating. In this design, a symmetrical DBC layout is utilized to balance parasitic inductances in the current pathways of paralleled dies to isolate the impact of parametric tolerances. In addition, the paper investigates the benefits of flexible PCB in place of wire bonds for the gate loop interconnection to reduce and minimize the gate loop inductance. The balanced modules have dies with similar threshold voltages while the unbalanced modules have dies with unbalanced threshold voltages to force unbalanced current sharing. The modules were placed into a clamped inductive DPT and a continuous, boost converter. Rogowski coils looped under the wire bonds of the bottom switch dies to observe current behavior. Four modules performed continuously for least 10 minutes at 200 V, 37.6 A input, at 30 kHz with 50% duty cycle. The modules could not perform for multiple minutes at 250 V with 47.7 A (23 A/die). The energy loss differential for a ~17% difference in threshold voltage ranged from 4.52% (~10 µJ) to -30.9% (~30 µJ). The energy loss differential for a ~0.5% difference in V_th ranged from -2.26% (~8 µJ) to 5.66% (~10 µJ). The loss differential was dependent on whether current unbalance due to on-state resistance compensated current unbalance due to threshold voltage. While device parametric tolerances are inherent, if the higher threshold voltage devices can be paired with devices that have higher on-state resistance, the overall loss differential may perform similarly to well-matched dies. Lastly, the most consistently performing unbalanced module with 17.7% difference in V_th had 119.9 µJ more energy loss and was 22.2°C hotter during continuous testing than the most consistently performing balanced module with 0.6% difference inV_th. / Master of Science / This paper describes the design, construction, and testing of advanced power devices for use in electric vehicles. Power devices are necessary to supply electricity to different parts of the vehicle; for example, energy is stored in a battery as direct current (DC) power, but the motor requires alternating current (AC) power. Therefore, power electronics can alter the energy to be delivered as DC or AC. In order to carry more power, multiple devices can be used together just as 10 people can carry more weight than 1 person. However, because the devices are not perfect, there can be slight differences in the performance of one device to another. One device may have to carry more current than another device which could cause failure earlier than intended. In this research project, multiple power devices were placed into a package, or "module." In a control module, the devices were selected with similar properties to one another. In an experimental module, the devices were selected with properties very different from one another. It was determined that the when the devices were 17.7% difference, there was 119.9 µJ more energy loss and it was 22.2°C hotter than when the difference was only 0.6%. However, the severity of the difference was dependent on how multiple device characteristics interacted with one another. It may be possible to compensate some of the impact of device differences in one characteristic with opposing differences in another device characteristic.
93

(a,b)-modules auto-adjoints et formes hermitiennes

Karwasz, Piotr P. 10 December 2009 (has links) (PDF)
Dans cette thèse nous présenterons un travail relatif à la théorie des (a,b)-modules. Nous nous intéresserons en particulier à trois problèmes liés à la dualité des (a,b)-modules: l'existence de formes hermitiennes, la symétrie des suites de Jordan-Hölder et la relation avec les "higher residue pairings" de K. Saito. Dans la première partie on étudie les équivalents des concepts de conjugué, adjoint et de forme hermitienne dans le contexte des (a,b)-modules. Dans notre analyse des formes hermitiennes nous sont amenés à définir la notion de (a,b)-module indécomposable et à montrer l'analogue du théorème de Krull-Schmidt dans la théorie des modules sur un anneau commutatif. On montre par la suite l'existence de formes ou bien hermitiennes ou anti-hermitiennes sur les modules réguliers indécomposables auto-adjoints et on donne un exemple non trivial de rang 4 admettant uniquement une forme anti-hermitienne. Suit une étude des suites de Jordan-Hölder de (a,b)-modules auto-adjoints. L'intérêt se porte en particulier sur les suites de Jordan-Hölder dites elles aussi auto-adjointes et on en montre l'existence, pour tout (a,b)-module régulier auto-adjoint. En guise de conclusion on applique les résultats obtenus aux (a,b)-modules associés à une hypersurface à singularité isolée, c'est-à-dire au complété formel de son module de Brieskorn. On montre que le symétrisé de l'isomorphisme avec l'adjoint donné par R. Belgrade satisfait aux axiomes donnés par K. Saito dans la présentation de ses "higher residue pairings".
94

Renewable energy/mains power integration controller and switching module

Wen, Yi-Han (Jennifer) January 2011 (has links)
This Masters research proposes a new system which deals with the management of renewable energy sources in a domestic/commercial small scale environment. The aim of the project is to develop an intelligent system which will monitor current in individual circuit loads in a domestic/commercial environment and establish whether the load can be powered from mains supply or be switched to an alternative energy supply in a dynamic way. The alternative energy can be solar energy from photovoltaic panels, wind generators or hydro generation. The switching between supplies is decided by monitoring load currents using a microcontroller and the switching action is taken only at specic allowed instants. The CAN (Controller Area Network)communication system is a two-wire differential serial bus system, developed by Bosch for automotive applications in the early 1980s. Its reliability and robustness in communication between nodes within the control system are the reasons for its popularity. The CAN system is implemented in the Eco Energy Controller. The prototype of the Eco Energy Controller is operational and has been tested with 6 resistive load, 24mH inductive load, and three 25W incandescent light bulbs. Experimental measurements and waveforms indicate that the prototype is successful in switching between two supplies to each of the loads without causing high current peaks during turn on.
95

Elucidation of structure and substrate-specificity of a glycoside hydrolase from family 81 and a carbohydrate binding module from family 56

Fillo, Alexander 24 December 2014 (has links)
The degradation of carbohydrates is essential to many biological processes such as cell wall remodelling, host-pathogen defense, and energy synthesis in the form of ATP. Several of these processes utilize carbohydrate-active enzymes to accomplish these goals. Studying the degradation of polysaccharides by carbohydrate-active enzymes synthesized by microbes has allowed us to further understand biomass conversion. A portion of these polysaccharides consists of β-1,3-linked glucose (i.e. β-1,3-glucan), which is found in plants, fungi, and brown macroalgae. The hydrolysis of β-1,3-glycosidic linkages is catalyzed by β-1,3-glucanases, which are present in six different glycoside hydrolase (GH) families: 16, 17, 55, 64, 81, and 128. These enzymes play important biological roles including carbon utilization, cell wall modeling, and pathogen defense. This study focuses on a gene from Bacillus halodurans encoding for a multi-modular protein (BhLam81) consisting of a glycoside hydrolase from family 81 (BhGH81), a carbohydrate-binding module (CBM) from family 6 (BhCBM6), and a CBM from family 56 (BhCBM56). Previously, thorough structural and substrate-specific characterization has been carried out on BhCBM6. This CBM binds the non-reducing end of β-1,3-glucan. A member of CBM family 56 has been shown to recognize and bind the insoluble β-1,3-glucan, pachyman, however it is structurally uncharacterized. A glycoside hydrolase belonging to family 81 from Saccharomyces cerevisiae has been previously shown to degrade the β-1,3-glucans, laminarin and pachyman, however the structure of this enzyme was not determined. Recently, a member of GH family 81 has been structurally characterized; however, substrate-specificity was not determined in that study. Therefore, this study concentrated on two goals: Determining the substrate-specificity of BhGH81 and BhCBM56, and solving the structure of BhGH81 and BhCBM56 in order to gain insight into the molecular details of how they recognize and act on their substrate(s). The deoxyribonucleic acid (DNA) encoding for these modules were dissected by restriction digest from B. halodurans genomic DNA and recombinantly expressed in Escherichia coli (E. coli) as separate constructs. Both BhGH81 and BhCBM56 were purified and their crystal structures obtained. BhGH81 and BhCBM56 were solved to 2.5 Å resolution by single-wavelength anomalous dispersion (SAD) and to 1.7 Å resolution by multi-wavelength anomalous dispersion (MAD), respectively. In order to determine the substrate-specificity of BhGH81 and BhCBM56 and speculate on the molecular details of how they recognize and act on their substrate(s), substrate-specificity tests were combined with structural analysis for both of these modules. By using qualitative depletion assays, quantitative depletion assays, and affinity electrophoresis, it was revealed that BhCBM56 binds both insoluble and soluble β-1,3-glucan. The crystal structure of BhCBM56 revealed that it is a β-sandwich composed of two antiparallel β-sheets consisting of five β-strands each. By comparing BhCBM56 to a β-1,3-glucan binding protein from Plodia interpunctella (βGRP) a putative substrate-binding cleft on the concave side of the β-sandwich created by a platform of hydrophobic residues surrounded by several polar and charged residues was revealed. This comparison also allowed for speculation of the amino acids (W1015, H965, and D963) that are potentially essential for recognition of β-1,3-glucan substrates by BhCBM56. Activity of BhGH81 on β-1,3-glucans was confirmed by both thin-layer chromatography and product analysis using high performance anion exchange chromatography. The high performance anion exchange chromatography of BhGH81 hydrolysis suggested it has both exo and endo modes of action. The crystal structure of BhGH81 revealed that it consists of domains A, B, and C: A β-sandwich domain (A), a linker domain (B), and an (α/α)6-barrel domain (C). This structure revealed a putative substrate-binding cleft on one side of the (α/α)6-barrel with a blind canyon active site topology. It also revealed two putative catalytic residues, E542 and E546. All GHs from family 81 characterized so far, hydrolyze β-1,3-glucan in an endo acting manner. By comparing the structure of BhGH81 acquired in this study to a cellulase from Thermobifida fusca, which has an endo-processive mode of action, we can speculate that BhGH81 also has an endo-processive mode of action. The structural and biochemical analysis of BhGH81 and BhCBM56 in this study has aided in further understanding the molecular details both GH family 81 and CBM family 56 proteins, as well as the degradation of β-1,3-glucan by multimodular enzymes. Understanding these molecular details could be important for industrial applications such as, engineering a microbial platform for more efficient biofuel production. / Graduate
96

Using differential adhesion to control self-assembly and self-repair of collections of modular mobile robots

Ottery, Peter January 2006 (has links)
This thesis presents a novel distributed control method which allows a collection of independently mobile robotic units, with two or three dimensional movement, to self-assemble into self-repairing hierarchical structures. The proposed method utilises a simple model of the cellular adhesion mechanisms observed in biological cells, allowing the robotic units to form virtually bonded aggregates which behave as predicted by Steinberg’s differential adhesion hypothesis. Simulated robotic units based on the design of the subaquatic HYDRON module are introduced as a possible platform on which the model can be implemented. The units are used to carry out a detailed investigation of the model behaviour and parameter space focusing on the two main tasks of rounding and sorting in both two and three dimensions. These tasks assess the model’s ability to reach a thermodynamically stable configuration when the aggregates consist of either a single population of units or multiple populations of units with differing adhesive properties. The results are analysed in detail with particular attention given to the role of random movements in determining the overall performance, and demonstrate that this model provides a very robust solution to these complex tasks. Finally, a possible extension of this work is presented in which the original model is combined with a genetic regulatory network controller. The performance of this composite is evaluated, and the benefits of this hybrid approach, in which a powerful control system manipulates a robust self-organising behaviour, are discussed.
97

Génération de patrons de conception et restructuration de code vers un patron de conception pour Java

Tousignant, Jonathan January 2016 (has links)
(POO) est l’utilisation de patrons de conception (PC). Un PC est un arrangement caractéristique de classes permettant d’offrir une solution éprouvée, tout en obtenant un code réutilisable et compréhensible. Plusieurs PC sont définis, dont 24 par la GoF [12] et plusieurs autres sont apparus par la suite. Le concept de PC est abstrait ce qui peut amener différentes interprétations. Ces différences peuvent aussi causer une mauvaise implémentation qui peut réduire les avantages d’utiliser ce patron. Ce projet consiste à concevoir un outil facilitant l’utilisation des PC. L’outil Génération et Restructuration de Patrons de Conception(GRPC) permet la génération automatique du squelette d’un patron de conception ainsi que la restructuration d’un code en le transformant structure respectant un PC. La génération et la restructuration automatique permettent d’obtenir un code uniforme et de qualité tout en respectant le patron de conception. La compréhension et la maintenance du code sont ainsi améliorées. GRPC est module d’extension pour l’environnement de développement Eclipse écrit en Java. Le code est conçu pour être facilement compréhensible et extensible. Les deux principaux objectifs de GRPC sont de restructurer (refactoring) une section de code vers l’architecture d’un patron de conception et de générer des squelettes de patrons de conception. Une interface graphique permet de guider l’utilisateur et d’aller chercher toutes les informations importantes pour le fonctionnement du logiciel. Elle permet aussi de configurer les éléments du patron de conception. Pour s’assurer de la possibilité d’effectuer une restructuration, chaque patron est associé avec une ou plusieurs règles qui analysent le code pour détecter la présence d’une structure particulière. Des procédures aident les développeurs à ajouter de nouveaux PC dans GRPC. GRPC fournit des fonctionnalités permettant d’implémenter quelques patrons de conception de la POO définis dans le livre Design Patterns : Elements of Reusable Object-Oriented Software.
98

Parallele Strategien für ein spektrales Wolkenmodul in einem 3-dimensionalen Mesoskalenmodell

Simmel, Martin, Reilein, Robert, Rünger, Gudula, Tetzlaff, Gerd 28 November 2016 (has links) (PDF)
A spectral cloud model is developed for a 3-dimensional mesoscale model considering only the microphysical conversion processes of the warm cloud. Because of the expected computation requirements, which are strongly increased in relation to the bulk-parameterization, we develop concepts for the parallelization of the module, explain their applicability and present first results. / Für ein 3-dimensionales Mesoskalenmodell wird ein spektrales Wolkenmodul entwickelt, das zunächst nur die mikrophysikalischen Umwandlungsprozesse der warmen Wolke berücksichtigt. Aufgrund des zu erwartenden, im Vergleich zur bulk-Parametrisierung stark erhöhten Rechenzeitbedarfs entwickeln wir Konzepte zur Parallelisierung des Moduls, erläutern deren Anwendbarkeit und stellen erste Ergebnisse vor.
99

Élaboration d’un module de raisonnement adaptable dédié aux risques liés à l’utilisation d’une cuisinière par des personnes âgées

Goujeau, Camille January 2017 (has links)
Le vieillissement de la personne implique généralement un déclin des fonctions cognitives et physiques pouvant apporter des risques dans la vie de tous les jours. Les personnes âgées tendent à vouloir rester vivre chez elles le plus longtemps possible, afin de conserver un sentiment d’indépendance. Cependant, cette volonté peut nécessiter des aménagements au domicile de la personne, afin d’assurer sa sécurité et rassurer son entourage. Cette sécurité passe notamment par la cuisine, qui est un lieu à haut risque. Un incendie peut facilement se déclarer si la personne âgée n’est pas assez attentive à ce qu’elle cuisine, tout comme la personne peut se brûler ou être intoxiquée par les émanations de fumées. Pour pallier à cette problématique de l’utilisation de la cuisinière par une personne âgée, nous proposons Inovus, un système permettant la prévention des risques majeurs liés à l’utilisation de la cuisinière, ainsi que des méthodes d’interventions pour avertir et protéger la personne de ces risques. Inovus regroupe un ensemble de capteurs surveillant des paramètres critiques liés à l’utilisation d’une cuisinière, dans le but de prévenir efficacement les trois risques majeurs identifiés, à savoir les incendies, les brûlures et les intoxications. Pour ces trois risques, un niveau de dangerosité est défini grâce à un module de raisonnement et un ensemble de règles linguistiques. En se basant sur ces niveaux de risque, Inovus va déterminer quelles sont les interventions à effectuer auprès de la personne pour l’avertir des risques et la protéger le plus efficacement possible. Ces interventions sont déterminées grâce à module de raisonnement qui évalue le niveau de risque auquel la personne est confrontée et décide des interventions les plus appropriées. Les interventions développées sont sensibles au contexte et à l’activité de la personne. En fonction de la position de la personne dans son domicile et du niveau de risque déterminé, les interventions s’effectueront au niveau de la cuisinière ou bien dans le reste du domicile. Plusieurs méthodes d’interventions sont proposées afin de s’assurer que la personne soit efficacement avertie des risques. Des interventions d’ordre lumineuses et sonores servent principalement à avertir la personne des risques. De plus des interventions sur les appareils intelligents de la personne sont également proposées afin de l’informer de la situation.
100

Self-adjoint (a,b)-modules and hermitian forms / (a,b)modules auto-adjoints et formes hermitiennes

Karwasz, Piotr Przemyslaw 10 December 2009 (has links)
Dans cette thèse nous présenterons un travail relatif à la théorie des (a,b)-modules. Nous nous intéresserons en particulier à trois problèmes liés à la dualité des (a,b)-modules: l'existence de formes hermitiennes, la symétrie des suites de Jordan-Hölder et la relation avec les "higher residue pairings" de K. Saito. Dans la première partie on étudie les équivalents des concepts de conjugué, adjoint et de forme hermitienne dans le contexte des (a,b)-modules. Dans notre analyse des formes hermitiennes nous sont amenés à définir la notion de (a,b)-module indécomposable et à montrer l'analogue du théorème de Krull-Schmidt dans la théorie des modules sur un anneau commutatif. On montre par la suite l'existence de formes ou bien hermitiennes ou anti-hermitiennes sur les modules réguliers indécomposables auto-adjoints et on donne un exemple non trivial de rang 4 admettant uniquement une forme anti-hermitienne. Suit une étude des suites de Jordan-Hölder de (a,b)-modules auto-adjoints. L'intérêt se porte en particulier sur les suites de Jordan-Hölder dites elles aussi auto-adjointes et on en montre l'existence, pour tout (a,b)-module régulier auto-adjoint. En guise de conclusion on applique les résultats obtenus aux (a,b)-modules associés à une hypersurface à singularité isolée, c'est-à-dire au complété formel de son module de Brieskorn. On montre que le symétrisé de l'isomorphisme avec l'adjoint donné par R. Belgrade satisfait aux axiomes donnés par K. Saito dans la présentation de ses "higher residue pairings" / In this thesis we present a work regarding the theory of (a,b)-modules. We are particularly interested in three problems related to the duality of (a,b)-modules: the existence of hermitian forms, the symmetry of Jordan-Hölder composition series and the relation with the "higher residue pairings" of K. Saito. In the first part we study the concepts of conjugate, adjoint and hermitian form in the theory of (a,b)-modules. Our analysis of hermitian forms brings us to the proof of the analogue of the Krull-Schmidt theorem in the theory of modules over a commutative ring. We prove afterwards the existence of either a hermitian or an anti-hermitian form on regular indecomposable self-adjoint (a,b)-modules and we give a non trivial rank 4 example of module that admits only an anti-hermitian form. Follows a study of the Jordan-Hölder composition series of self-adjoint (a,b)-modules. We are in particular interested in a kind of composition series also called self-ajoint, whose existence we prove for every regular self-adjoint (a,b)-module. In the last part the results obtained are applied to (a,b)-modules associated to a hyper-surface with an isolated singularity, i.e. to the formal completion of the Brieskorn module. We show that a symmetrized form of the isomorphism with the adjoint given by R. Belgrade satisfies the axioms given by Saito for his "higher residue pairings"

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