Multilevel inverters have advantages over two-level inverters such as reduced THD, ability to operate at low switching frequencies, reduced switching losses etc. Moreover, higher voltage levels can be handled with devices of lower voltage rating. The main disadvantage with the multilevel configurations compared to the two-level inverter configuration is the increase in the number of power devices required and the circuit complexity, which necessitates complex control schemes that add to the cost. Also, the reliability of the converters comes down as the number of devices increases. Reduction in complexity and modularity are desirable characteristics for the multilevel inverters. Open-end winding Induction Motor (IM) drive configurations are shown to have advantages over the motor drive schemes with isolated neutral. The DC-link requirement in case of open-end winding structures comes down to half the voltage rating of the conventional NPC inverters. The DC- link requirement in case of open-end winding structures comes down to half compared to that of the conventional NPC inverters. The number of switching states is higher in the case of open-end winding configuration compared to multiplicity of switching states of conventional NPC inverters, which gives a control flexibility that can be used for optimizing the hardware requirements. Taking advantage of the flexibility given by open-end winding configuration, this thesis proposes schemes which have reduced power circuit complexity. Non-sinusoidal voltage fed IM drives suffer from the problems related to the common mode voltage (CMV) generated by the inverters. This CMV causes bearing currents and shaft voltages which in turn cause increased conducted EMI, ground loop currents and premature bearing failure. A three-level scheme was proposed for an open-end winding Induction machine in the literature, which completely eliminate the CMV variation from the pole voltages as well as the phase voltages. This configuration uses 24 controlled switches and two isolated DC-sources. In this thesis, three-level inverter schemes with CMV elimination and reduced power device count for an open-end winding IM drive are proposed. The first scheme gets the reduction in switch count by sharing the top inverter of the three-level scheme and the second scheme achieves the same by sharing the bottom inverter. This way, the number of controlled switches comes down to 18 from 24. Another problem with multilevel inverters is the large number of isolated DC-sources required to achieve the multilevel inversion. Reducing the number of isolated supplies and using capacitors to split the voltage levels poses the problem of capacitor voltage balancing. A four-level inverter with both CMV elimination and capacitor voltage balancing for an open-end winding IM drive is proposed in this thesis. The motor is fed by two four-level inverters from both the sides. A closed loop capacitor voltage balancing scheme is implemented and the redundancies in the switching states are used for achieving the capacitor voltage balancing and thereby reducing the total number of DC-link to two. The control scheme is independent of the load power factor and maintains the balance in the entire modulation range. A five-level inverter scheme is proposed for an open-end winding IM drive in this thesis. It requires only two isolated DC-sources to achieve the five-level inversion. The motor is fed by one NPC three-level inverter from one side and a two-level inverter from the other. The inverters on either side share the DC-sources. Common mode voltage in the phases are made zero in an average sense using sine-triangle modulation in the proposed scheme so that the common mode currents through the phases are suppressed. The maximum fundamental voltage that can be obtained at the phase is limited to 0.5Vdc. DC-link requirement of the inverter scheme is half of that of conventional five-level inverter scheme because of the open-end winding structure. The two-level inverter, which should withstand half the DC-link voltage, is always in square wave operation and hence the switching losses are very less. All the schemes are simulated extensively in MATLAB/Simulink and experimentally verified on laboratory prototypes under V/f control. TI Motor control DSP and Xilinx CPLD/FPGA are used for generation of the PWM signals for the schemes. The inverters are switched at around 1.25 kHz to keep the switching losses low. Due to laboratory constraints, the experimental verification is done on low power prototypes. Nonetheless, the generality of the schemes allow them to be used for medium voltage high power applications.

published_or_final_version / Architecture / Master / Master of Architecture

In 2004, students at the University of Guelph designed and constructed an all-wheel-drive Formula SAE vehicle for competition. It utilized an electronically-controlled, hydraulic-actuated limited slip center coupling from Haldex Traction Ltd, to transfer torque to the front wheels. The initial control system design was not comprehensively conceived, so there was a need for a thoroughly developed control system for the all-wheel-drive actuator augmented with commonly available sensors and a low cost controller. This thesis presents a novel all-wheel-drive active torque transfer controller using a neural network estimated slip angle velocity. This controller specifically targets a racing vehicle by allowing rapid direction changes for maneuverability but damping slip angle changes for increased controllability. The slip angle velocity estimate was able to track the actual simulated value it was trained against with excellent phase matching but with some offsets and phantom spikes. Using the estimated slip angle velocity for control realized smooth control output, excellent stability, and a fast turn-in yaw response on par with rear-wheel-drive configurations. A full vehicle simulation with software-in-the-loop testing for control software was also developed to aid the system design process and avoid vehicle run time for tuning. This design flow should significantly decrease development time for controls algorithm work and help increase innovation within the team.

Les jeunes marins que nous sommes amenés à rencontrer dans le cadre de notre activité clinique semblent être dans un balancement entre le désir de voyager et une tendance naturelle à vouloir rester à terre, à proximité de leur famille. Au-delà de la description symptomatologique, qui évoque ce que l’on appelle communément une dépendance affective, définie par le fait que le sujet a des difficultés à s’éloigner de ses repères affectifs, et est en proie, lorsqu’il y est confronté, à la dépression, nous nous sommes demandés si cette dépendance n’était pas en tout point constitutive de la subjectivité humaine. En effet, l’enfant se développe au plan psychique dans une dépendance à la mère, avant de s’autonomiser progressivement, tout en gardant inscrites dans son inconscient les marques de cette dépendance. Qu’est-ce qui, dans ce contexte, invite les marins au voyage ? Dans cette perspective, nous avons, par l’étude de la littérature classique, exploré le déterminisme de ces êtres, tel qu’il a été perçu et décrit par les écrivains au fils des époques. Nous avons découvert chez ces marins un dualisme entre volonté de découverte, d’exploration, et besoin de demeurer sur la terre ferme. Nous avons également mis en évidence que la navigation faisait office de contenant pour le psychisme, et permettait de lutter contre la survenue d’une dépression secondaire à la séparation. Nous avons aussi démontré qu’il existait chez certains de ces marins une réactualisation de la problématique œdipienne. Enfin, nous en avons conclu qu’il s’agissait pour eux de mettre en œuvre, au travers de cette problématique, leur propre rapport à la vie et à la mort. / In our clinical domain, we are bound to come across young sailors who seem torn between a sheer desire to take to sea and a natural attraction to the shore, close to their loved ones. The symptomatogical description, more commonly know as an emotional dependence, refers to the patient's difficulty to move away from his emotional markers and his proclivity to depression in such instance. Our research work has consisted in reflecting on the close link between that very dependence and human subjectivity. Indeed, a child's psychological development depends on the mother, retaining unconscious traces of that dependence while gradually acquiring his autonomy. So we may wonder what attracts sailors to embark on a journey in that particular context. Therefore we have explored the determinism of those beings as felt and described in classical literature. We have found that these sailors waver between exploring the world and staying ashore. We have also highlighted that navigating takes the role of a recipient to the mind/psyche and enables the subject to fight any depression resourcing from separation. We have also shown that some sailors experience a return to an oedipal condition. Finally, we have come to the conclusion that, by means of experience, sailors work through their own relationship to life and death.

Solid State Diskar (SSD) är relativt nya och mycket om dem är okänt. Detta examensarbete fokuserar på att läsa forensiskt viktig information från både lagringsutrymmet och reservutrymmet. Detta har försökts genom att ett program har byggts i C++, detta program använder ATA kommandon för att läsa information från disken. Även om programmet aldrig blev färdigt kunde det skicka och ta emot data från en SSD, dock inte reservutrymmet vilket var fokus i detta examensarbete. / Solid State Drives (SSD) are relatively new and not much is known about them. This thesis focuses on retrieving forensically important information, not only from the storage area of the SSD but also from the spare area. This was attempted by writing a program in C++ that, using ATA commands, could read information from the SSD. Although the program was not finished within the given time, it could read some information from the SSD, but not the spare area which was the main focus.

Molnlagringstjänster används alltmer och är en växande marknad. Uppsatsen har fokuserat på att undersöka olika molnlagringstjänster ur ett hastighetsperspektiv. När små filer utbyts mellan klient och server har hastigheten på överföringen en mindre betydelse. Vid större överföringar får hastighetsaspekten en alltmer viktig roll. Regelbundna hastighetsmätningar har utförts mot de mest populära molnlagringstjänsterna. Testerna har utförts från Sverige och USA. Testerna har utförts under flera dagar och under olika tidpunkter på dygnet, för att undersöka om hastighetsskillnader existerar. Resultaten visar att stora skillnader finns i hastighet mellan Sverige och USA. Inom Sverige hade Mega och Goolgle Drive högst medelhastighet. Inom USA hade Google Drive högst medelhastighet, men här var variationerna mellan tjänsterna ej lika stora som i Sverige. I resultaten mellan olika tidpunkter var det svårare att urskilja ett mönster, med undantag för Google Drive i Sverige som konsistent fungerade bäst på natten/morgonen. Även Mega fungerade bäst under natten. / Cloud Storage services have seen increased usage and is an emerging market. This paper has focused on examining various cloud storage services from a speed perspective. When small files are exchanged between client and server, the speed of the service is of little importance. For larger transfers however, the speed of the service used plays a more important role. Regular speed measurements have been carried out against the most popular cloud storage services. The tests have been performed from Sweden and USA. The tests have been carried out over several days and at different times of day, to determine if speed differences exist. The results show that there are significant differences in speed between Sweden and the United States. In Sweden, Mega and Google Drive had the highest average speed. Within the United States, Google Drive had the highest average speed, but the variability between the services was not as great as in Sweden. In the results between different timeperiods, it was difficult to discern a pattern, with the exception of Google Drive in Sweden which consistently worked best during the night / morning. Mega also worked best during the night.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-07T12:17:37Z No. of bitstreams: 1 anapaulasoarescampos.pdf: 496075 bytes, checksum: d5d3679c1f15801b7d782cd17fb7eb68 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T16:42:35Z (GMT) No. of bitstreams: 1 anapaulasoarescampos.pdf: 496075 bytes, checksum: d5d3679c1f15801b7d782cd17fb7eb68 (MD5) / Made available in DSpace on 2016-01-25T16:42:35Z (GMT). No. of bitstreams: 1 anapaulasoarescampos.pdf: 496075 bytes, checksum: d5d3679c1f15801b7d782cd17fb7eb68 (MD5) Previous issue date: 2015-02-10 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Com a impossibilidade de sustentar o primeiro dualismo, Freud se viu diante da ameaça de ter que admitir um monismo pulsional. No entanto, Freud sempre considerou fundamental pressupor um dualismo. Em Além do princípio do prazer (1920), ao refletir sobre a relação entre a compulsão à repetição e a atividade pulsional, ele chega ao conceito de pulsão de morte. Em oposição a esta nova classe de pulsão, Freud apresenta a pulsão de vida e, assim, substitui o primeiro dualismo pulsional. Ambas as classes de pulsões teriam entrado em ação com o surgimento da vida a partir da matéria inorgânica. Enquanto a pulsão de morte buscaria retornar ao estado inorgânico, a pulsão de vida buscaria complexificar a vida, dificultando a morte do organismo. Mas a hipótese do segundo dualismo apresenta uma série de dificuldades, que colocam em questão até que ponto Freud conseguiu sustentá-la. Ele próprio reconhece, na obra de 1920, que o novo dualismo pulsional não apresenta o mesmo grau de certeza que os passos anteriores do desenvolvimento de sua teoria das pulsões. O objetivo deste trabalho é, em primeiro lugar, analisar a teoria apresentada em Além do princípio do prazer e discutir alguns dos principais problemas presentes na argumentação freudiana. Em seguida, procuramos analisar as hipóteses elaboradas por Freud sobre as duas classes de pulsões em textos posteriores, tendo em vista analisar em que medida ele consegue sustentar a primariedade e a independência das duas classes de pulsões no restante de sua teoria. Concluímos que os impasses presente no texto de 1920 não são plenamente solucionados e procuramos apontar as principais questões que permanecem em aberto na teoria freudiana acerca do segundo dualismo pulsional. / With the impossibility of sustaining the first dualism, Freud was faced with the threat of having to admit a drive monism. However, Freud always considered fundamental to assume a dualism. In Beyond the Pleasure Principle (1920), when reflecting on the relationship between the repetition compulsion and drive activity, he gets the concept of the death drive. In opposition to this new drive class, Freud presents the life drive and, thus, replaces the first drive dualism. Both drive classes would act with the emergence of life from inorganic matter. While the death drive would return to the inorganic state, the life drive would make the life more complex, making the death of the organism harder. However, the second dualism hypothesis presents a number of difficulties which begs the question if Freud was able to sustain this. In his work of 1920, he recognizes that the new drive dualism does not present the same degree of certainty that the previous steps of the development of his theory of drives. The objective here is, first, to analyze the theory presented in Beyond the Pleasure Principle and discuss some of the main problems present in Freud's argument. Then we analyzed the hypotheses developed by Freud regarding the two drive classes in later works in order to analyze how he can sustain the primarity and independence of the two drive classes in the remaining of his theory. We conclude that the impasses in the text of 1920 are not fully solved and we try to point out the main issues that remain open in the Freudian theory about the second drive dualism.

Os objetivos deste estudo foram comparar os níveis de inibição pré-sináptica (IPS) durante a iniciação do passo entre indivíduos com doença de Parkinson (DP) com bloqueio motor (BM), sem-BM (S-BM) e indivíduos saudáveis pareados pela idade (ISPI) e, possíveis correlações entre os níveis de IPS com as variáveis comportamentais (amplitude e tempo do ajuste postural antecipatório [APA]) e os escores do New Freezing of Gait Questionnaire (NFOG-Q). A amostra foi composta por 22 indivíduos com BM e 12 S-BM (estágio 3 da DP avaliados no estado on da medicação). Dezesseis ISPI também foram incluídos no estudo. Todos atenderam os critérios de inclusão. Os indivíduos foram avaliados em dois dias. No primeiro dia, todos responderam uma anamnese e o Mini Exame do Estado Mental. Para os indivíduos com DP foi aplicada a escala de estadiamento da DP e a parte III da Escala Unificada de Avaliação da DP (UPDRS) e somente os indivíduos com BM foram avaliados com o NFOG-Q. No segundo dia, todos os indivíduos realizaram a tarefa iniciação do passo na plataforma de força AMTI para avaliação da amplitude e do tempo do APA com ou sem a evocação do reflexo-H na condição teste ou condicionado. O estimulador portátil Nicolet® Viking Quest da CareFusion foi utilizado para evocar o reflexo-H teste e condicionado. O estímulo elétrico foi evocado quando a amplitude do APA ultrapassasse 10 a 20% da linha de base. Todos indivíduos realizaram a tarefa iniciação do passo em 3 condições: 1) sem estímulo; 2) estímulo teste estimulação no nervo tibial; e 3) estímulo condicionado estimulação do nervo fibular antes (intervalo de 100 ms) da estimulação do nervo tibial. Nas três condições, os indivíduos foram instruídos a realizarem 15 passos, logo, 15 estímulos nas condições 2 e 3 de maneira aleatória. A ANOVA one way mostrou diferenças significantes nos valores de IPS entre os três grupos, onde os ISPI apresentaram valores maiores de IPS do que os outros dois grupos e, indivíduos S-BM apresentaram valores maiores IPS comparado aos indivíduos com BM (P<0,001), porém, todos os indivíduos deste último grupo apresentaram facilitação. Adicionalmente, amplitudes maiores e tempos menores do APA foram observados somente para os ISPI (P<0,05), além disso, não foram observadas diferenças entre essas variáveis para os dois grupos de DP (P>0,05). Em relação às correlações, especialmente para os indivíduos com BM, observamos que valores maiores de facilitação estão: fortemente associados com os escores maiores do NFOG-Q (r = -74; P<0,0001); moderadamente associados com as amplitudes menores do APA (r = 0,54; P<0,004); e fracamente associados com os tempos maiores do APA (r = -0,42; P<0,244). Por fim, houve uma forte associação entre as amplitude menores do APA e escores maiores do NFOG-Q (r = -,075; P<0,0001). Em conclusão, indivíduos com BM apresentam facilitação (ausência de IPS) durante a iniciação do passo e associada com deficiências na amplitude e tempo do APA e a severidade do BM. Isso indica que a medula espinhal tem participação na iniciação do passo e pode ser fortemente influenciada por alterações sensório-motoras / The aims of this study were to compare the presynaptic inhibition levels (PSI) in the step initiation between subjects with Parkinson\'s disease (PD) with freezing of gait (FoG), non-FOG (non-FoG), and age-matched healthy controls (HC) and, possible correlations between the PSI levels with the behavioral variables and the New Freezing of Gait Questionnaire (NFOG-Q) scores. Twenty individuals with FoG, 12 individuals with non-FoG (stage 3 of PD assessed in the clinically defined on state), and 16 HC met the inclusion criteria. Subjects visited the laboratory for two days. On the first day, all of the subjects answered the anamnesis and the Mini-Mental State Examination. However, only in the subjects with PD were assessed the severity of disease and the motor symptoms (Unified Parkinson´s Disease Rating Scale part III [UPDRS-III], but the FoG severity was assessed only in the subjects with FoG. On the second day, all of the subjects performed the step initiation on the force platform (AMTI) to assess amplitude and time of anticipatory postural adjustment with or without evoking H-reflex in the test or conditioned condition. The constant-current stimulator (Nicolet® Viking Quest portable EMG apparatus, CareFusion) was used to evoke the H-reflex. The electrical stimulus was evoked when the APA amplitude exceeded 10 to 20% of the baseline. All of the subjects performed the step initiation in 3 conditions: 1) without stimulation of the nerve; 2) test stimulus stimulation of the tibial nerve; and 3) conditioning stimulus - stimulation of the fibular nerve before (100 ms interval) stimulation of the tibial nerve. At three conditions, subjects were instructed to perform 15 steps, thus, 15 stimuli at conditions 2 and 3 in a random order. The ANOVA one way showed significant differences in the PSI values between the three groups, where the ISPI presented higher values of PSI than the other two groups, and S-BM individuals had higher PSI values compared to individuals with BM (P<0.001), however all of the individuals with FoG presented facilitation. In addition, larger amplitudes and smaller times of APA were observed only for ISPI (P<0.05); in addition, no differences were observed between these variables for the two PD groups (P>0.05). In relation to correlations, especially for individuals with FoG, we observed that greater values of facilitation are: strongly associated with the higher NFOG-Q scores (r = -0.74; P<0.0001); moderately associated with the smaller APA amplitudes (r = 0.54; P<0.004); and weakly associated with higher APA times (r = -0.42, P<0.244). Finally, there was a strong association between the smaller APA amplitudes and higher NFOG-Q scores (r = -0.75, P<0.0001). In conclusion, individuals with FoG presented facilitation (absence of PSI) in the step initiation which was associated with deficits in amplitude and time of APA and FoG severity. This indicates that the spinal cord has participation in the step initiation that can be strongly influenced by the abnormal sensory motor

The subject of this diploma thesis is determination of the cause of crack formation at the carriage Top drive for MND Drilling & Services company. The aim of the diploma thesis is to analyze the load states of the component. Furthermore, the aim is to create a computational model and boundary conditions and to create suggestions of improvements leading to the elimination of cracks. And finally, to evaluate the results of construction improvements..

This master thesis deals with the mechanical and electrical design of the drive of the inclined construction lift. Individual components are selected in the design. Furthermore, a theoretical research is carried out regarding wireless modules and logic controllers. The selection of sensors is made and the method of retrieving signals from sensors and converting them into iputs the control circuits is also outlined. A program is written in Arduino IDE that wirelessly controls the motion of a motor via variable frequency drive.