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1

Todoran, Alexandru Mihai. "Magnetron sputtering in inverted cylindrical configuration : 3D deposition on moving substrate". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI082.

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Les travaux présentés dans cette thèse constituent une étude sur la possibilité de déposer par pulvérisation plasma des couches minces de TiN sur des fils d'acier inoxydable en défilement. Les aspects technologiques tels que la conception et la construction d'une ligne prototype capable de nettoyer et déposer sur toute la circonférence des substrats cylindriques en mouvement sont présentés. Le développement de procédé dans la chambre de nettoyage par micro-ondes a permis l'amélioration des performances du plasma en termes de densité et de température d'électronique, ce qui a conduit à une amélioration de l'efficacité de nettoyage de substrat en termes de degré de propreté et de temps de traitement requis. D'une manière similaire, le développement de procédé dans la chambre de dépôt a permis de mettre en évidence la limitation majeure du magnétron cylindrique inversée (ICM), soit la très haute température atteinte par le substrat pendant le procédé. Le calcul théorique a permis l'identification de la majeure contribution au chauffage du substrat, et, afin de la réduire, la mise en place d'une solution technique consistant en électrodes supplémentaires, indépendamment polarisées. L'impact de la polarisation des électrodes supplémentaires est présenté en termes de paramètres de procédé (confinement du plasma, redistribution des courants, potentiel de la cible, modes de pulvérisation, temps de traitement plus permis, etc.), et, également, en termes de propriétés de couches déposées (vitesse de dépôt, profil d'épaisseur, composition et stœchiométrie). Basés sur les résultats obtenus dans le magnétron actuel, plusieurs possibilités d'améliorer encore les performances d'une nouvelle chambre de dépôt sont discutées
This thesis represents a study of the possibility to sputter - deposit titanium nitride thin films on moving stainless steel wires. Technological aspects such as the conception, design and construction of a prototype tool capable of in-line cleaning and deposition all around the circumference of moving cylindrical substrates are presented. The process development in the microwave cleaning chamber allowed the improvement of the plasma performance in terms of density and electron temperature, which lead to improvement of the substrate cleaning efficiency in terms of degree of cleanliness and required process time. Similarly, the process development in the deposition chamber permitted to highlight the major limitation of the inverted cylindrical magnetron (ICM), which is the very high temperature, the substrate reaches during process. Theoretical calculation allowed the identification of the major contribution to substrate heating, and a technical solution consisting of independently biased additional electrodes is proposed in order to reduce it. The impact of the additional electrodes polarization is discussed both in terms of process parameters (plasma confinement, electron current redistribution, target voltage, sputtering modes, longer allowable process time, etc.), and in terms of films properties (deposition rate, thickness profile, composition and stoichiometry). Based on the results obtained in the present ICM, several possibilities to improve the performance of a new magnetron are discussed
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2

McCrindle, Rachel Jane. "Inverse software configuration management". Thesis, Durham University, 1998. http://etheses.dur.ac.uk/5013/.

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Software systems are playing an increasingly important role in almost every aspect of today’s society such that they impact on our businesses, industry, leisure, health and safety. Many of these systems are extremely large and complex and depend upon the correct interaction of many hundreds or even thousands of heterogeneous components. Commensurate with this increased reliance on software is the need for high quality products that meet customer expectations, perform reliably and which can be cost-effectively and safely maintained. Techniques such as software configuration management have proved to be invaluable during the development process to ensure that this is the case. However, there are a very large number of legacy systems which were not developed under controlled conditions, but which still, need to be maintained due to the heavy investment incorporated within them. Such systems are characterised by extremely high program comprehension overheads and the probability that new errors will be introduced during the maintenance process often with serious consequences. To address the issues concerning maintenance of legacy systems this thesis has defined and developed a new process and associated maintenance model, Inverse Software Configuration Management (ISCM). This model centres on a layered approach to the program comprehension process through the definition of a number of software configuration abstractions. This information together with the set of rules for reclaiming the information is stored within an Extensible System Information Base (ESIB) via, die definition of a Programming-in-the- Environment (PITE) language, the Inverse Configuration Description Language (ICDL). In order to assist the application of the ISCM process across a wide range of software applications and system architectures, die PISCES (Proforma Identification Scheme for Configurations of Existing Systems) method has been developed as a series of defined procedures and guidelines. To underpin the method and to offer a user-friendly interface to the process a series of templates, the Proforma Increasing Complexity Series (PICS) has been developed. To enable the useful employment of these techniques on large-scale systems, the subject of automation has been addressed through the development of a flexible meta-CASE environment, the PISCES M4 (MultiMedia Maintenance Manager) system. Of particular interest within this environment is the provision of a multimedia user interface (MUI) to die maintenance process. As a means of evaluating the PISCES method and to provide feedback into die ISCM process a number of practical applications have been modelled. In summary, this research has considered a number of concepts some of which are innovative in themselves, others of which are used in an innovative manner. In combination these concepts may be considered to considerably advance the knowledge and understanding of die comprehension process during the maintenance of legacy software systems. A number of publications have already resulted from the research and several more are in preparation. Additionally a number of areas for further study have been identified some of which are already underway as funded research and development projects.
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3

Hazarika, Neep. "An inverse method for blended wing-body configurations". Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/12498.

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4

Alqarni, Mohammed. "A high efficiency photovoltaic inverter system configuration with maximum power point tracking". Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/12767.

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The increase in demand for renewable energy sources has been exponential in recent years and is mainly driven by factors that include the growth of greenhouse emissions and the decline in fossil fuel reservoirs. Photovoltaic (PV) energy, one of the more prominent renewable energy sources, produces electricity directly from sunlight, noiselessly and harmlessly to the environment. Additionally, PV energy systems are easy to install and financially supported by many governments, which has helped disseminate PV technology worldwide. The total generated power from PV installations (and the number of installations) has increased more than two-fold during the past 3 years, so that now more than 177 GW of PV-generated power is delivered per year. Researchers have been led to work on the obstacles facing PV systems from different perspectives, including: installation cost, inconsistency, and conversion and interface efficiency. The aim of this thesis is to design a high-efficiency PV inverter system configuration. The contribution to the knowledge in this thesis can be divided into two parts. The first part contains a critical analysis of different maximum power point tracking (MPPT) techniques. The second part provides a detailed design of the inverter system, which consists of a boost converter and a low-frequency H-bridge. Together, the three parts in this contribution present a complete high efficiency PV inverter system. The proposed system maintains high-efficiency energy delivery by reducing the number of high-frequency switches, which waste a significant amount of energy and reduce system efficiency. In order to show the superiority of the proposed configuration, a power loss analysis comparison with the other existing configurations is presented. In addition, different scenarios have been simulated with Matlab/Simulink. The results of these simulations confirm the distinction of the proposed configuration as well as its low-loss, high-efficiency characteristics which is rated at 98.8%.
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5

Ozdemir, Mustafa. "Inverse Dynamics Control Of Parallel Manipulators Around Singular Configurations". Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609212/index.pdf.

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In this thesis, a technique for the motion of parallel manipulators through drive singularities is investigated. To remedy the problem of unbounded inverse dynamics solution in the neighborhood of drive singularities, an inverse dynamics controller which uses a conventional inverse dynamics control law outside the neighborhood of singularities and switches to the mode based on the formerly derived modified equations inside the neighborhood of singularities is proposed. As a result, good tracking performance is obtained while the actuator forces remain within the saturation limits of the actuators around singular configurations.
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6

Grudić, Gregory Z. "Iterative inverse kinematics with manipulator configuration control and proof of convergence". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/42018.

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A complete solution to the inverse kinematics problem for a large class of practical manipulators, which includes manipulators with no closed form inverse kinematics equations, is presented in this thesis. A complete solution to the inverse kinematics problem of a manipulator is defined as a method for obtaining the required joint variable values to establish the desired endpoint position, endpoint orientation, and manipulator configuration; the only requirement being that the desired solution exists. For all manipulator geometries that satisfy a set of conditions (THEOREM I), an algorithm is presented that is theoretically guaranteed to always converge to the desired solution (if it exists). The algorithm is extensively tested on two complex 6 degree of freedom manipulators which have no known closed form inverse kinematics equations. It is shown that the algorithm can be used in real time manipulator control. Applications of the method to other 6 DOF manipulator geometries and to redundant manipulators are discussed.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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7

Voznyuk, Ivan. "Méthodes de décomposition de domaines pour la modélisaton électromagnétique et l'imagerie micro-onde quantitative dans des configurations tridimensionnelles de grande taille". Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4732/document.

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Cette thèse porte sur la modélisation des ondes électromagnétiques en milieu complexe et à haute fréquence. Ceci reste un défi, de part les besoins en temps de calcul et en place mémoire que cela suscite. L'idée de la méthode Finite Element Tearing and Interconnect (FETI) est de diviser le domaine en sous-domaines distincts dans lesquels des problèmes électromagnétiques peuvent être résolus de manière indépendante. Une modification de la méthode classique, appelée FETI-DPEM2-full, est ici proposée afin d'améliorer le processus numérique. Les champs diffractés par différents objets ont ainsi été simulés et comparés avec succès à des champs expérimentaux. A partir de ces champs, les techniques d'imagerie micro-onde permettent de déterminer les paramètres électromagnétiques des objets illuminés. Ce problème inverse peut être réécrit sous la forme d'un problème d'optimisation faisant appel à la résolution de deux problèmes directs à chaque itération. Une méthode de type quasi-Newton a donc été couplée efficacement avec la méthode FETI-DPEM2-full. Des reconstructions obtenues à partir de champs mesurés sont présentées et valident la chaîne méthodologique proposée
This PhD work is devoted to the electromagnetic modeling of threedimensional large-scale wave propagation problems, which is very challenging in terms of memory and computation time. The main idea of the Finite Element Tearing and Interconnect (FETI) method is to divide the domain into non-overlapping subdomains where each electromagnetic problem can be independently solved. A modification of the classical FETI method, called the FETI-DPEM2-full method, is proposed herein to improve the numerical process. The fields scattered by various structures have thus been computed and successfully compared with measured fields. From these experiments, quantitative microwave imaging algorithms attempt to estimate the physical parameters of the illuminated target. This inverse problem is recasted into a minimization problem where two forward problems are required at each iteration step. A quasi-Newton algorithm has thus been efficiently coupled with the FETI-DPEM2-full method. Reconstructions of various targets from measured scattered fields have been successfully performed, which validates the effectiveness of the proposed methodology
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8

Vilamot, Raphaël. "Optimisation de la configuration magnétique d'un propulseur à effet Hall par résolution du problème magnétostatique inverse". Phd thesis, Toulouse, INPT, 2012. http://oatao.univ-toulouse.fr/14668/1/vilamot.pdf.

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Les travaux effectués lors de cette thèse portent sur l'optimisation de la configuration magnétique des propulseurs à effet Hall. Ceci regroupe deux objectifs: d'une part la réalisation d'un propulseur à effet Hall dont la topologie magnétique est entièrement paramétrable, ce qui constituera un outil précieux pour l'étude de l'impact du champ magnétique sur le fonctionnement du propulseur et d'autre part, l'étude de moyen de conception rationalisée de circuits magnétiques pour ces mêmes propulseurs. Le premier sujet a conduit à la réalisation du PPS-Flex, un propulseur proposant une structure de circuit magnétique innovante offrant un grand nombre de degrés de liberté en termes de réglage du champ magnétique produit. La deuxième thématique a quant à elle été abordée en s'appuyant sur des méthodes d'optimisation (paramétrique et topologique) permettant d'aboutir à un circuit magnétique optimal pour un ou plusieurs critères de conception (fidélité du champ magnétique généré, minimisation de la masse, du volume total, etc.)
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9

Akteke, Basak. "Derivative Free Optimization Methods: Application In Stirrer Configuration And Data Clustering". Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/2/12606591/index.pdf.

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Recent developments show that derivative free methods are highly demanded by researches for solving optimization problems in various practical contexts. Although well-known optimization methods that employ derivative information can be very effcient, a derivative free method will be more effcient in cases where the objective function is nondifferentiable, the derivative information is not available or is not reliable. Derivative Free Optimization (DFO) is developed for solving small dimensional problems (less than 100 variables) in which the computation of an objective function is relatively expensive and the derivatives of the objective function are not available. Problems of this nature more and more arise in modern physical, chemical and econometric measurements and in engineering applications, where computer simulation is employed for the evaluation of the objective functions. In this thesis, we give an example of the implementation of DFO in an approach for optimizing stirrer configurations, including a parametrized grid generator, a flow solver, and DFO. A derivative free method, i.e., DFO is preferred because the gradient of the objective function with respect to the stirrer&rsquo
s design variables is not directly available. This nonlinear objective function is obtained from the flow field by the flow solver. We present and interpret numerical results of this implementation. Moreover, a contribution is given to a survey and a distinction of DFO research directions, to an analysis and discussion of these. We also state a derivative free algorithm used within a clustering algorithm in combination with non-smooth optimization techniques to reveal the effectiveness of derivative free methods in computations. This algorithm is applied on some data sets from various sources of public life and medicine. We compare various methods, their practical backgrounds, and conclude with a summary and outlook. This work may serve as a preparation of possible future research.
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10

Dhib, Soumaya. "Contribution à l'optimisation de la Configuration et à l'évaluation de performances des réseaux logistiques inverses : cas des déchets des équipements électriques et électroniques". Thesis, Paris 8, 2017. http://www.theses.fr/2017PA080033/document.

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Les durcissements réglementaires relatifs à la gestion environnementale et à la responsabilité écologique forcent de plus en plus les industriels à respecter l’environnement dans leur déploiement et développement. A l’heure où on parle de la diminution de la durée de vie des produits de consommation et des biens durables, ces industriels ont désormais la mission de mettre en place des processus de valorisation de leurs produits en fin de vie et des dérivés de leur productions. Cela a été notamment le cas des équipements informatiques et électroniques qui cherchent à concevoir des réseaux logistiques qui répondent aux besoins de gestions des flux de leurs retours comme les DEEE1. En effet, ils sont soumis à des fortes sollicitations (maîtrise des destinations de valorisation de produits en fin de vie, réduction des coûts de traitement, réduction de l’impact des activités logistiques associées sur l’environnement, …). Ce travail s’intéresse à la conception des réseaux logistiques des flux de retours qui sont soumis naturellement aux contraintes économiques mais aussi à celles environnementales. Quelques-uns des facteurs complexifiant du problème comme : l’état de retour, la fluctuation de la demande en produits valorisés, … sont pris en compte dans la recherche de la configuration du réseau logistiques qui répond au mieux aux besoins
Regulatory tightening on environmental management and environmental responsibility increasingly forces industrialists to respect the environment in their deployment and development. At a time when we are talking about the shortening of the life span of consumer products and durable goods, these manufacturers now have the task of putting in place processes for the valorization of their end-of-life products and derivatives of their products productions. This has been the case in particular for computer and electronic equipment which seeks to design logistic networks that meet the management needs of the flows of their returns such as WEEE1. Indeed, they are subject to strong demands (mastery of destinations for valorisation of end-of-life products, reduction of processing costs, reduction of the impact of associated logistical activities on the environment, etc.). This work deals with the design of logistic networks of returns flows which are naturally subject to economic constraints but also to environmental ones. Some of factors of the problem such as: return status, fluctuations in the demand for valued products, etc. are taken into account in the search for the configuration of the logistics network that best meets the needs
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11

Poling, Dana B. "Spherically-actuated platform manipulator". Ohio : Ohio University, 2000. http://www.ohiolink.edu/etd/view.cgi?ohiou1172775949.

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12

Barrière, Paul-André. "DÉVELOPPEMENT D'ALGORITHMES D'INVERSION RAPIDES ET PROPOSITIONS RELATIVES À LA CONFIGURATION DU MONTAGE DE MESURES DANS UN CONTEXTE DE TOMOGRAPHIE MICRO-ONDES APPLIQUÉE À LA DÉTECTION DU CANCER DU SEIN". Phd thesis, Ecole centrale de nantes - ECN, 2008. http://tel.archives-ouvertes.fr/tel-00390344.

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Cette thèse porte sur la tomographie micro-ondes appliquée à la détection du cancer du sein. Les aspects algorithmiques ainsi que ceux reliés à la configuration du montage de mesure y sont traités.

Le temps nécessaire à la reconstruction d'une image étant critique pour d'éventuelles applications cliniques de la tomographie micro-ondes, nous proposons, en première partie, une série d'algorithmes qui offrent un coût de calcul diminué par rapport aux méthodes concurrentes. La méthode « current source inversion » (CSI) est utilisée comme point de départ de la réflexion. On identifie certaines faiblesses de cet algorithme et on en propose deux généralisations, plus rapides et plus robustes. Deux nouvelles familles de méthodes, s'attaquant à différents goulots d'étranglement des méthodes CSI généralisées, sont aussi proposées. Elles sont basées sur deux nouvelles formulations du problème direct. La première est mathématiquement équivalente à celle d'origine alors que la seconde est basée sur des approximations.

En ce qui a trait à la configuration du montage de mesures, on montre que la résolution des images reconstruites peut être significativement améliorée en ayant recours à la compression du sein. On propose aussi un montage qui exploite les propriétés des guides d'ondes diélectriques. Celui-ci permet de mesurer le champ dans l'air plutôt que dans un liquide d'adaptation, ce qui ouvre la porte au développement de montages plus compacts.
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13

Bacour, Cédric. "Contribution à la détermination des paramètres biophysiques des couverts végétaux par inversion de modèles de réflectance : analyses de sensibilité comparatives et configurations optimales". Paris 7, 2001. http://www.theses.fr/2001PA077164.

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14

Aristidou, Andreas. "Tracking and modelling motion for biomechanical analysis". Thesis, University of Cambridge, 2010. https://www.repository.cam.ac.uk/handle/1810/237554.

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This thesis focuses on the problem of determining appropriate skeletal configurations for which a virtual animated character moves to desired positions as smoothly, rapidly, and as accurately as possible. During the last decades, several methods and techniques, sophisticated or heuristic, have been presented to produce smooth and natural solutions to the Inverse Kinematics (IK) problem. However, many of the currently available methods suffer from high computational cost and production of unrealistic poses. In this study, a novel heuristic method, called Forward And Backward Reaching Inverse Kinematics (FABRIK), is proposed, which returnsvisually natural poses in real-time, equally comparable with highly sophisticated approaches. It is capable of supporting constraints for most of the known joint types and it can be extended to solve problems with multiple end effectors, multiple targets and closed loops. FABRIK wascompared against the most popular IK approaches and evaluated in terms of its robustness and performance limitations. This thesis also includes a robust methodology for marker prediction under multiple marker occlusion for extended time periods, in order to drive real-time centre of rotation (CoR) estimations. Inferred information from neighbouring markers has been utilised, assuming that the inter-marker distances remain constant over time. This is the firsttime where the useful information about the missing markers positions which are partially visible to a single camera is deployed. Experiments demonstrate that the proposed methodology can effectively track the occluded markers with high accuracy, even if the occlusion persists for extended periods of time, recovering in real-time good estimates of the true joint positions. In addition, the predicted positions of the joints were further improved by employing FABRIK to relocate their positions and ensure a fixed bone length over time. Our methodology is tested against some of the most popular methods for marker prediction and the results confirm that our approach outperforms these methods in estimating both marker and CoR positions. Finally, an efficient model for real-time hand tracking and reconstruction that requires a minimumnumber of available markers, one on each finger, is presented. The proposed hand modelis highly constrained with joint rotational and orientational constraints, restricting the fingers and palm movements to an appropriate feasible set. FABRIK is then incorporated to estimate the remaining joint positions and to fit them to the hand model. Physiological constraints, such as inertia, abduction, flexion etc, are also incorporated to correct the final hand posture. A mesh deformation algorithm is then applied to visualise the movements of the underlying hand skeleton for comparison with the true hand poses. The mathematical framework used for describing and implementing the techniques discussed within this thesis is Conformal GeometricAlgebra (CGA).
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15

Butt, Munam. "Systemization of RFID Tag Antenna Design Based on Optimization Techniques and Impedance Matching Charts". Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23064.

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The performance of commercial Radio Frequency Identification (RFID) tags is primarily limited by present techniques used for tag antenna design. Currently, industry techniques rely on identifying the RFID tag application (books, clothing, etc.) and then building antenna prototypes of different configurations in order to satisfy minimum read range requirements. However, these techniques inherently lack an electromagnetic basis and are unable to provide a low cost solution to the tag antenna design process. RFID tag performance characteristics (read-range, chip-antenna impedance matching, surrounding environment) can be very complex, and a thorough understanding of the RFID tag antenna design may be gained through an electromagnetic approach in order to reduce the tag antenna size and the overall cost of the RFID system. The research presented in this thesis addresses RFID tag antenna design process for passive RFID tags. With the growing number of applications (inventory, supply-chain, pharmaceuticals, etc), the proposed RFID antenna design process demonstrates procedures to design tag antennas for such applications. Electrical/geometrical properties of the antennas designed were investigated with the help of computer electromagnetic simulations in order to achieve optimal tag performance criteria such as read range, chip-impedance matching, antenna efficiency, etc. Experimental results were performed on the proposed antenna designs to compliment computer simulations and analytical modelling.
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16

Murphy, Leanne. "Influence of High Mobility Polymer Semiconductors in Organic Photovoltaics". Thesis, 2013. http://hdl.handle.net/10012/7442.

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Increasing global energy demands and diminishing supplies of conventional fuels are forcing the world to focus more on alternative power sources that are both renewable and ecologically benign. Solar energy is clean, regularly available and can be harvested without sacrificing valuable land space. Due to the associated cost of solar cells, however a very small portion of the world’s energy needs are supplied by the sun. Solution-processable organic photovoltaics (OPVs) offer the promise of lower production costs relative to conventional (silicon) solar cell technology. Solution-processing can be performed using reel-to-reel manufacturing, with printing and coating techniques that are significantly cheaper than current processing methods for inorganic semiconductors. Although OPV efficiency values currently remain inferior to those of conventional solar cells, the rate of improvement is much higher in OPVs than in other solar cell technologies. Recently an efficiency exceeding 10% was reported for organic solar cells. An important difference between organic and conventional solar cells is the charge carrier mobility of the semiconductors, which tends to be relatively low in organic semiconductors. Recent advances in molecular design have led to polymer semiconductor materials that possess hole mobility values similar to that of amorphous silicon. The present study investigates potential improvements in OPV devices that can be achieved through the application of high hole mobility polymer semiconductor donors. Two diketopyrrolopyrrole-based polymers, PDQT and PDBFBT, were selected for the role of electron donor in OPV devices due to their high mobilities and their optimum optical and electrical properties. Optimization of the process parameters was performed using PC61BM as the acceptor. A relatively high quantity of PC61BM (3 - 4 × the weight of the donor) is required in the donor-acceptor blends of both polymers in order to balance the high hole mobility. For these donor-acceptor blends, a solvent system consisting of chloroform/ortho-dichlorobenzene (4:1 v/v) is necessary for proper solubility, and an additive, 1,8-diiodooctane, is required to achieve an acceptable morphology. The main benefit expected from the use of high mobility semiconductors is reduced charge recombination. This was studied in relation to the active layer thickness in standard and inverted OPV devices prepared using PC61BM as the acceptor. Normally the thickness of the active layer is required to be low (~100 nm) due to the poor charge transport mobility of the carriers. In this study, rather consistent power conversion efficiencies were achieved throughout a wide range of active layer thicknesses (~100 nm to ~800 nm). A comparison between standard and inverted device configurations demonstrates that the inverted configuration is more suitable for achieving thicker active layers when a high hole mobility donor is used. This is attributed to the longer hole collection path in the inverted structure, which can benefit from using a high hole mobility material. Increasing the absorption spectra of the donor-acceptor blend was studied by substituting PC71BM for PC61BM. The improved absorption leads to greater charge generation. In PDQT devices, the increase in absorption that is contributed by PC71BM appears to be of greatest benefit when active layers are not very thick. Therefore, when thick active layers (>500 nm) are required, the use of PC61BM is sufficient, in conjunction with a high mobility donor. Finally, an increase in a polymer’s crystallinity can often lead to greater mobility. This can be accomplished through various annealing techniques. The improved crystallinity of PDBFBT that occurs as a result of thermal annealing was studied in OPV applications. Although hole mobility of PDBFBT in the lateral direction improves with thermal annealing, mobility in the vertical direction decreases with increasing temperature. This suggests that the crystallinity of PDBFBT is oriented in the lateral direction as opposed to the vertical direction, thereby directing charge flow horizontal to the surface. With thermal annealing, an optimal amount of PC61BM added to PDBFBT can increase the vertical mobility to fairly high values. Nevertheless, the efficiency of standard and inverted OPV devices decreases with increased annealing temperature. This is attributed to agglomeration of PC61BM that occurs from an increase in annealing temperature. The results of this study demonstrate that thermal annealing is not beneficial for PDBFBT:PC61BM films in OPV applications due to the vertical orientation of devices. All of the studies presented in this work involve the use of high hole mobility polymer semiconductors as donor materials for OPV applications. This work will provide a deeper understanding of the properties required for the development of new semiconductor materials in OPV applications. Furthermore, this work will be very useful for the design of device structures for more feasible manufacturing of large area OPV devices via high speed roll-to-roll printing processes.
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17

Liou, Syuan-Hao y 劉軒豪. "Reye’s Configuration of Polyhedra Inversed from Archimedean Solid". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/25274518047745986475.

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18

Wang, Tai-Hung y 汪泰宏. "A Cascode-Circuit Configuration for Grid-Tied Solar Micro-Inverters". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/63133202009768911628.

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博士
國立臺灣科技大學
電子工程系
103
This dissertation presents the design and implementation of a DSP-based grid-tied solar cascode-micro-inverter. General cascode-inverter architecture is mainly used in multi-stage high-voltage output. The general inverter is used connected directly by several of switching elements in cascode mode. This dissertation presents a grid-tied controlled cascode AC module. The proposed solar inverter with maximum power point tracking (MPPT) function is connected with the AC grid by a cascode-circuit configuration. In order to make inverter achieve the purpose of modular, each inverter uses the unipolar switching for single-phase full-bridge inverter. Using the proposed single-stage power conversion configuration, low system complexity, high conversion efficiency, high MPPT accuracy and low harmonic distortion can be achieved. The simulation and experimental results of a 300 W prototype system were shown to verify the feasibility of the proposed configuration.
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19

Chaing, Meng-Ting y 蔣孟廷. "A Three-Dimensional Inverse Geometry Problem in Estimating the Unknown Boundary Configurations". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/50580034683872134009.

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碩士
國立成功大學
系統及船舶機電工程學系碩博士班
95
A three-dimensional inverse geometry problem (shape identification problem), which is very limited in the literatures, in determining the unknown irregular surface configurations by utilizing the conjugate gradient method (CGM) and a general purpose commercial code CFD-RC is successfully developed and examined in this study based on the simulated measured temperature distributions on the bottom surface by infrared thermography. The advantage of calling CFD-RC as a subroutine in the present inverse calculation lies in that its auto mesh function enables the handling of this moving boundary problem. Results obtained by using the technique of CGM to solve the inverse geometry problem are justified based on the numerical experiments. Three test cases are performed to test the validity of the present algorithm by using different types of surface shapes, initial guess and measurement errors. Results show that excellent estimations on the unknown surface geometry can be obtained with any arbitrary initial guesses.
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20

Tabandeh, Saleh. "Development of Novel Task-Based Configuration Optimization Methodologies for Modular and Reconfigurable Robots Using Multi-Solution Inverse Kinematic Algorithms". Thesis, 2009. http://hdl.handle.net/10012/4959.

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Modular and Reconfigurable Robots (MRRs) are those designed to address the increasing demand for flexible and versatile manipulators in manufacturing facilities. The term, modularity, indicates that they are constructed by using a limited number of interchangeable standardized modules which can be assembled in different kinematic configurations. Thereby, a wide variety of specialized robots can be built from a set of standard components. The term, reconfigurability, implies that the robots can be disassembled and rearranged to accommodate different products or tasks rather than being replaced. A set of MRR modules may consist of joints, links, and end-effectors. Different kinematic configurations are achieved by using different joint, link, and end-effector modules and by changing their relative orientation. The number of distinct kinematic configurations, attainable by a set of modules, varies with respect to the size of the module set from several tens to several thousands. Although determining the most suitable configuration for a specific task from a predefined set of modules is a highly nonlinear optimization problem in a hybrid continuous and discrete search space, a solution to this problem is crucial to effectively utilize MRRs in manufacturing facilities. The objective of this thesis is to develop novel optimization methods that can effectively search the Kinematic Configuration (KC) space to identify the most suitable manipulator for any given task. In specific terms, the goal is to develop and synthesize fast and efficient algorithms for a Task-Based Configuration Optimization (TBCO) from a given set of constraints and optimization criteria. To achieve such efficiency, a TBCO solver, based on Memetic Algorithms (MA), is proposed. MAs are hybrids of Genetic Algorithms (GAs) and local search algorithms. MAs benefit from the exploration abilities of GAs and the exploitation abilities of local search methods simultaneously. Consequently, MAs can significantly enhance the search efficiency of a wide range of optimization problems, including the TBCO. To achieve more optimal solutions, the proposed TBCO utilizes all the solutions of the Inverse Kinematics(IK) problem. Another objective is to develop a method for incorporating the multiple solutions of the IK problem in a trajectory optimization framework. The output of the proposed trajectory optimization method consists of a sequence of desired tasks and a single IK solution to reach each task point. Moreover, the total cost of the optimized trajectory is utilized in the TBCO as a performance measure, providing a means to identify kinematic configurations with more efficient optimized trajectories. The final objective is to develop novel IK solvers which are both general and complete. Generality means that the solvers are applicable to all the kinematic configurations which can be assembled from the available module inventory. Completeness entails the algorithm can obtain all the possible IK solutions.
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21

Villard, L. "Modélisation directe et inverse des observables radar à synthèse d'ouverture en configuration bistatique. Applications à la télédétection des milieux forestiers". Phd thesis, 2009. http://tel.archives-ouvertes.fr/tel-01066878.

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Le radar à synthèse d'ouverture (RSO) constitue un instrument unique en télédétection des forêts, fort des propriétés physiques micro-ondes en sus d'atouts opérationnels. Néanmoins, l'utilisation de la sensibilité des mesures SAR aux variables d'intérêts in-situ n'est pas triviale et constitue de multiples axes de recherche dont l'étude de la configuration bistatique. Le succès de récentes acquisitions aéroportées (e.g campagne conjointe ONERA-DLR) ou hybrides témoigne d'une certaine résurgence pour la géométrie bistatique, principalement mis en avant pour des considérations opérationnelles. La question du potentiel physique des observables bistatiques reste cependant peu traitée. La thèse s'inscrit dans cet objectif, via l'étude de configurations bistatiques optimales pour améliorer l'inversion de paramètres in-situ d'intérêts, tout en considérant leur faisabilité. Dans ce cadre, la modélisation électromagnétique est fondamentale, illustrée ici par le développement du simulateur ad-hoc MIPERS dont les originalités par rapport aux modèles existants ont démontré toute leur importance pour analyser ces nouvelles observables. Des extensions novatrices des algorithmes de référence en monostatique basées sur l'intensité et l'interférométrie vectorielle pour une estimation directe de la biomasse ou via l'inversion de paramètres descriptifs de modèles de forêts sont alors proposées, à l'issue de formulations théoriques supportées par les résultats de simulations. Outre de futures campagnes expérimentales bistatiques, sont aussi mises en avant les perspectives innovantes de configurations multistatiques.
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22

Bagot, Jonathan. "Single-Query Robot Motion Planning using Rapidly Exploring Random Trees (RRTs)". 2014. http://hdl.handle.net/1993/23829.

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Robots moving about in complex environments must be capable of determining and performing difficult motion sequences to accomplish tasks. As the tasks become more complicated, robots with greater dexterity are required. An increase in the number of degrees of freedom and a desire for autonomy in uncertain environments with real-time requirements leaves much room for improvement in the current popular robot motion planning algorithms. In this thesis, state of the art robot motion planning techniques are surveyed. A solution to the general movers problem in the context of motion planning for robots is presented. The proposed robot motion planner solves the general movers problem using a sample-based tree planner combined with an incremental simulator. The robot motion planner is demonstrated both in simulation and the real world. Experiments are conducted and the results analyzed. Based on the results, methods for tuning the robot motion planner to improve the performance are proposed.
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