Th. doct.-ing.--Électrotech.--Toulouse--I.N.P., 1979. N°: 64.

Th. doct.-ing.--Électrotech.--Toulouse--I.N.P., 1979. N°: 50.

Th. doct.-ing.--Électrotech.--Toulouse--I.N.P., 1979. N°: 49.

Sensorless speed estimation in induction machines (IMs) presents an attractive proposition for eliminating the need for physical speed measurement sensors and thus avoiding the associated reliability and cost issues, such as the requirement of extra wiring, careful mounting, maintenance and adjustment. In this thesis, the feasibility of utilising the stator current and power signals to establish spectral search based (SSB) sensorless speed estimation schemes in wound rotor induction machines (WRIMs) operating in extended slip and open-loop controlled conditions is investigated. The research is performed on three different industrial WRIM designs. The thesis first investigates the spectral content of WRIM electrical and mechanical signals with the principal aim of identifying spectral patterns that can facilitate the development of real-time sensorless speed estimation. The examination is based on detailed harmonic models of the considered machine designs as well as experimental results obtained from tests performed on laboratory test rigs. A generalised theoretical analysis of the possible spectral content of machine signals that enables the derivation of closed form analytical expressions linking individual spectral frequencies to rotor speed is also undertaken. The results demonstrate that it is possible to clearly identify speed dependent components in the stator current and power signals and map the boundaries of the narrowbands maximised by these for extended slip and open-loop operating conditions. To enable improvement in attainable real time SSB estimation rates a dichotomous search algorithm real-time spectral processing method was employed for frequency tracking in this research. The algorithm performance is evaluated in real-time tests performed on a measured steady-state laboratory machine stator current and power signals. The results demonstrate that the dichotomous routine provides an inherent advantage in the frequency estimation rate without compromising the estimation accuracy and can therefore enable significant estimation rate improvement in SSB speed estimation algorithms. Novel sensorless speed SSB estimation techniques are then proposed for WRIM operation in extended slip and voltage/frequency controlled conditions. The algorithms utilise the reported analysis of electrical signals and are separately defined for each assessed operation mode and the stator current, phase power and three-phase power signals. It is shown that, in principle, power signal based estimation algorithms can offer an inherent capability of estimation rate reduction. A novel adaptive sliding window algorithm is defined for open-loop operating conditions that enable estimation in a wide operating speed range while minimising the potential for undesirable overlap with PWM harmonics. The proposed algorithms have been verified and their performance limitations assessed in real-time experiments on three different industrial WRIM designs. It is shown that reliable real-time speed estimation in steady-state and transient operating conditions is possible at an improved estimation rate while maintaining a low estimation error.

Les travaux présentés dans cette thèse visent à proposer des méthodes d’optimisation des changements de série sur des lignes de production afin d’améliorer la flexibilité de la production. Nous modélisons ce problème sous forme de problème à machines parallèles non reliées : les tâches sont les réglages des machines d’une ligne et les ressources sont des opérateurs. Nous prenons en compte notamment, la structure de la ligne de production qui comporte des machines en plusieurs exemplaires, les compétences des opérateurs et leurs disponibilités. Les méthodes utilisées sont une procédure par séparation et évaluation dans le cas où la ligne est composée de machines en série et des heuristiques de type descente locale et algorithme génétique dans le cas général. Nous proposons des bornes permettant d’évaluer les performances des méthodes. Pour le cas série, nous proposons également une méthode hybride faisant collaborer une procédure par séparation et évaluation et un algorithme génétique. / The work presented in this thesis aims at proposing new methods for setup optimization in production lines in order to improve production flexibility. This problem is modelized using an unrelated parallel machines problem : the tasks are the setup tasks of each machine of the production line and the ressources are the operators. We take into consideration the production line structure that may contain multiple machines on some stages and the skills of operators. The skill model has been validated using a simulation approach. We have used a Branch-and-Bound to solve the special case of serial production line and hill climbing and genetic algorithm meta heuristics for the general case. In both cases, we propose bounds that are used to evaluate the performances of the different methods. For the serial special case, we also propose a hybrid algorithm that use both a genetic algorithm and a Branch-and-Bound that are colaborating together.

Software systems may contain sensitive data that should be protected. In a scenario, where an analyst has full access to the system, it may be desirable to transform the program to become harder to understand and reverse-engineer, while preserving the original functionality of the program. Machine code obfuscation tackles this problem by adding complexity to the pro- gram's control flow, a programming idiom removal, and various abstractions. Specifically, WProtect is an obfuscation engine that utilises a stack virtual ma- chine and its own instruction set to achieve these properties. In this thesis, I will analyse WProtect obfuscation engine, its obfuscation algo- rithms and present a generic approach to an extraction of a code protected by WProtect. Furthermore, I will design a generic framework for a static code ex- traction that is tweakable in order to support different WProtect configurations. Several improvements to WProtect, both in terms of configuration and design, will also be proposed. These proposals mostly intend to mitigate vulnerabilities that are exploited in the code extraction, however, several proposals shall also include improvements specifically targeting static analysis prevention. 1

It has been suggested that gambling behaviour may not be solely controlled by schedules of reinforcement, but may be under the control of verbal behaviour. Relational frame theory is a contemporary account of verbal behaviour which may be able to account for aspects of gambling behaviour that cannot be explained by a pure schedule of reinforcement account. Chapter 2 demonstrated that contextual cues may influence preferences for concurrently available slot-machines, thus overriding the contingencies of reinforcement in place. Chapter 3 demonstrated that the presence of accurate or inaccurate rules may influence slot-machine choice and affect gambling persistence. Participants that received inaccurate rules regarding the payout probability of a slot machine, gambled for longer than those given accurate rules. Chapter 4 reported that the discriminative functions of slot-machines could be transformed in accordance with derived same and opposite relations, such that participants showed preferences for slot-machines that had never been experienced before. Chapter 5 demonstrated that not only could preferences for concurrently available slot machines be transformed in accordance with derived comparative relations, but found that preferences for slot machines increased relative to the relational network that had been trained. In Chapter 6, ratings of wins, near-misses and losses on a computer simulated slot-machine could be altered in accordance with derived same and opposite relations, and could even override the non-arbitrary properties of a slot-machine. It was concluded that gambling is verbal behaviour and can be accounted for by derived relations and the transformation of function. These findings may explain instances of gambling behaviour which cannot be accounted for by the direct acting contingencies.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2014-11-10T11:55:57Z No. of bitstreams: 0 / Made available in DSpace on 2014-11-10T11:55:57Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-06-11T19:30:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2003Bitstream added on 2014-06-13T18:59:52Z : No. of bitstreams: 1 perez_ep_me_guara.pdf: 1116117 bytes, checksum: 2ae25303ba483b9f7ccbf3d2f842125f (MD5) / A turbina Michell-Banki é basicamente uma máquina de ação, sendo que a característica mais importante das turbinas de ação é a não existência do tubo de sucção. A instalação do tubo de sucção numa turbina causa o aumento da queda disponível e como conseqüência, aumenta a potência gerada e a rotação da turbina. No presente trabalho propõe-se a instalação de um tubo de sucção numa turbina Michell-Banki, visando alcançar as melhorias já indicadas acima, lembrando que ao colocar o tubo de sucção aparece um grau de reação na máquina. Foi feito uma análise mecânica-hidráulica da turbina Michell-Banki proposta, com o objetivo de encontrar as equações que permitem calcular os diversos elementos da turbina. Desta maneira o trabalho apresenta uma metodologia para projeto de uma turbina Michell-Banki com tubo de sucção. Também são apresentadas as formas de traçar o rotor, o injetor e a pá diretriz. Finalmente o trabalho apresenta ainda as recomendações para a execução de projeto e construção da turbina. / The turbine Michell-Banki is basically an action machine, and the important characteristic of the action turbines is the no existence of the suction tube. The installation of the suction tube in a turbine increases the available fall and as consequence, it increases the generated power. The rotation of the turbine is also increased by increasing the available fall. In the present work it's proposed the installation of a suction tube in a Michell-Banki turbine, aiming to reach the improvements already indicated above, remembering that when placing the suction tube a reaction degree appears in the machine. It was done an mechanical and hydraulics analysis of the Michell-Banki turbine with the objective of finding the equations that allow to calculate the several elements of the turbine proposed, and thus presenting a methodology for project of a turbine. Finally I described the way of drawing the rotor, the injector and the guideline shovel, as well as it is also recommended the process that should be followed to build the turbine.

Orientador: Milton Dias Junior / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T17:45:50Z (GMT). No. of bitstreams: 1 Melo_RicardoDoriguelode_M.pdf: 2568683 bytes, checksum: 002c8b8c586f3e8a033cbcb180693f2c (MD5) Previous issue date: 2010 / Resumo: O motor de combustão interna, embreagem, transmissão, diferencial, eixo Cardan, semieixos e rodas motrizes compõem o trem de potência de um veículo que, por diversas razões de refinamento e peso, oferecem baixa "resistência" aos ruídos decorrentes da irregularidade de rotação do motor. O presente trabalho reúne elementos para analisar os efeitos das flutuações de rotação (vibrações torsionais) presentes nos volantes de motores de quatro tempos durante a fase de desenvolvimento de sistemas de embreagem em veículos abastecidos com diferentes combustíveis: gasolina, álcool (etanol) e diesel. O uso de simulação matemática computacional permite amenizar ou eliminar os ruídos provenientes da transmissão no veículo protótipo ou até mesmo de um veículo virtual, possibilitando assim ganhos significativos no tempo de desenvolvimento de discos de embreagem e/ou volantes de dupla massa. Esta simulação nos indica também qual melhor tecnologia para diminuir as flutuações provenientes do motor do veículo: se o disco de embreagem ou o volante de dupla massa / Abstract: The internal combustion engine, clutch, transmission, differential, propeller shaft, half shafts and driven wheels compose the powertrain of a vehicle which, due to several reasons of refinement and weight, offer low noise "counter resistance" to engine irregularity. This report is a collection of elements to analyze the effects of the engine revolution irregularity (torsional vibration) present on flywheels of 4-stroke engines in the development of clutch systems in the vehicles supplied with different fuels: gas, alcohol and diesel. The use of computer simulation allows to soften or to eliminate the noise deriving from the transmission of prototype vehicles our virtual vehicles with new powertrain combination (clutch discs and/or dual-mass-flywheels), bringing considerable development time gains. This simulation showed the best technology reduces the engine revolution irregularity presents in the vehicles: if clutch disc or dual mass flywheel / Mestrado / Dinâmica / Mestre em Engenharia Automobilistica