With automobile propulsion energy sources turning away from petroleum, the evolution of technology naturally lends itself to electrical hybrid vehicle architectures relying on alternatives as a primary electrical energy source. This thesis presents a design solution of a direct-drive and drive-by-wire prototype of a hybrid extended range electric vehicle (EREV) based on a dune buggy test bed. The developed setup eliminates nearly all mechanical inefficiencies in the rear wheel drive transaxle drivetrain. All controls have been purposely designed as a duplicate set to allow for full independent control of both rear wheels in a truly independent architecture. Along with the controls supporting the design, the motors have been mounted in a near wheel fashion to adequately replace a true hub motor setup. In addition, by-wire throttle and by-wireless brakes in a servomechanical fashion have been developed. The by-wireless braking system is used to control regenerative braking for the rear of the vehicle only allowing for the front brakes to be the primary means of braking as well as a mechanical safety redundancy. This design allows for developments in the areas of truly independent electronic differential systems and studies of the effect of near wheel motor setup. The efficiencies gained by the design solutions implemented in this thesis project have shown their ability to be used in a functioning motor vehicle. Direct gains in mechanical efficiency as well as the removal of a non eco-friendly gasoline powertrain have been attained. In addition, an electric architecture has been developed for further research in future studies such as vehicle stability control, traction control and all-wheel-drive architectures.

Multi-ribbed serpentine belt is the core of the automotive accessory drive system, which distributes the engine power to other auxiliary systems of the car. Development of a belt life model is of a significant importance to the accessory drive system manufacturers, in order to prevent any premature failures of these belts. However, any numerical analysis on the belt life is heavily dependent on gaining an understanding of stress distribution in the belts under the operational loading conditions. The presented work demonstrates a new systematic approach for determining the hyperelastic material parameters of rubber with specific application in Finite Element Analysis (FEA) of serpentine accessory drive belts. This new approach can be used as a stand-alone tool by manufacturers to determine the stress distribution in the belt under operational conditions; the results of which can be applied to assess the life of accessory drive belts, in a relatively short time.

Multi-ribbed serpentine belt is the core of the automotive accessory drive system, which distributes the engine power to other auxiliary systems of the car. Development of a belt life model is of a significant importance to the accessory drive system manufacturers, in order to prevent any premature failures of these belts. However, any numerical analysis on the belt life is heavily dependent on gaining an understanding of stress distribution in the belts under the operational loading conditions. The presented work demonstrates a new systematic approach for determining the hyperelastic material parameters of rubber with specific application in Finite Element Analysis (FEA) of serpentine accessory drive belts. This new approach can be used as a stand-alone tool by manufacturers to determine the stress distribution in the belt under operational conditions; the results of which can be applied to assess the life of accessory drive belts, in a relatively short time.

This thesis aims to present solutions to improve the performance of SQLite library on mobile systems. In particular, two approaches are presented to add lightweight locking mechanisms to the SQLite library and improve concurrency of the SQLite library on Android operating system. The impact on performance is discussed after each section. Many applications on the Android operating system rely on the SQLite library to store ordered data. However, due to heavy synchronization primitives used by the library, it becomes a performance bottleneck for applications which push large amount of data into the database. Related work in this area also points to SQLite database as one of the factors for limiting performance. With increasing network speeds, the storage system can become a performance bottleneck, as applications download larger amounts of data. The following work in this thesis addresses these issues by providing approaches to increase concurrency and add light-weight locking mechanisms. The factors determining the performance of Application Programming Interfaces provided by SQLite are first gathered from IO traces of common database operations. By analyzing these traces, opportunities for improvements are noticed. An alternative locking mechanism is added to the database file using byte-range locks for fine-grained locking. Its impact on performance is measured using SQLite benchmarks as well as real applications. A multi-threaded benchmark is designed to measure the performance of fine grained locking in multi-threaded applications using common database operations. Recent versions of SQLite use write ahead logs for journaling. We see that writes to this sequential log can occur concurrently, especially in flash drives. By adding a sequencing mechanism for the write ahead log, the writes can proceed simultaneously. The performance of this method is also analyzed using the synthetic benchmarks and multi-threaded benchmarks. By using these mechanisms, the library is observed to gain significant performance for concurrent writes.

This dissertation aims at developing techniques to achieve high power density in motor drives under the performance requirements for transportation system. Four main factors influencing the power density are the main objects of the dissertation: devices, passive components, pulse width modulation (PWM) methods and motor control methods. Firstly, the application of SiC devices could improve the power density of the motor drive. This dissertation developed a method of characterizing the SiC device performance in phase-leg with loss estimation, and claimed that with SiC Schottky Barrier Diode the advantage of SiC JFET could benefit the motor drive especially at high temperature. Then the design and improvement of the EMI filter in the active front-end rectifier of the motor drive was introduced in this dissertation. Besides the classical filter design method, the parasitic parameters in the passive filter could also influence the filtering performance. Random PWM could be applied to reduce the EMI noise peak value. The common-mode (CM) noise reduction by PWM methods is also studied in this dissertation. This dissertation compared the different PWM methods’ CM filtering performance. Considering the CM loop, the design of PWM methods and switching frequency should be together with the CM impedance. Variable switching frequency PWM (VSFPWM) methods are introduced in the dissertation for the motor drive’s EMI and loss improvement. The current ripple of the three-phase converter could be predicted. Then the switching frequency could be designed to adapt the current ripple requirements. Two VSFPWM methods are introduced to satisfy the ripple current peak and RMS value requirements. For motor control issue, this dissertation analyzed the principle of the start-up transient and proposed an improved start-up method. The transient was significantly reduced and the motor could push to high speed and high power with speed sensorless control. Next, the hardware development of modular motor drive was introduced. The development and modification of 10kW phase-legs and full power test of a typical 30kW modular converter is realized with modular design method. Finally, the techniques developed in this dissertation for high power density motor drive design and control are summarized and future works are proposed.

Thesis (M.Eng.(Mechanical and Aeronautical Engineering))--University of Pretoria, 2008. / Includes bibliographical references.

Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-08-21T14:33:23Z No. of bitstreams: 1 DissSM.pdf: 674702 bytes, checksum: a1347e662fa95536cc5f05ef488cc9fe (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-21T14:33:30Z (GMT) No. of bitstreams: 1 DissSM.pdf: 674702 bytes, checksum: a1347e662fa95536cc5f05ef488cc9fe (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-21T14:33:36Z (GMT) No. of bitstreams: 1 DissSM.pdf: 674702 bytes, checksum: a1347e662fa95536cc5f05ef488cc9fe (MD5) / Made available in DSpace on 2017-08-21T14:33:42Z (GMT). No. of bitstreams: 1 DissSM.pdf: 674702 bytes, checksum: a1347e662fa95536cc5f05ef488cc9fe (MD5) Previous issue date: 2017-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The purpose of this paper is to discuss Freud's dualistic drive, arguing that the transition from one dualism to another is not a rupture in his theory, but rather a movement in his thinking. For this, we start from the analysis of the concept of drive, marking its specificity when compared to the animal instinct and showing how the sexual drives and the drives of self-preservation allowed the appearance of two different ways of processing the psychic energy. Next, we deal with the psychic conflict that begins with the process of repression and has as a background duel between sexuality and self-preservation, a subject that interests us, because we will see how the clinic and its impasses end up bringing problems to the first Theory. For this reason, we will deal with the difficulties brought about by paraphrenias and by the concept of narcissism that end up smoothing the first dualism. Finally, we will see how traumatic neurosis and the compulsion to repetition bring new elements to Freud and culminate in the elaboration of a new definition of the drive, which will now also be thought from the dispute between the life drives and the death drive. / Este trabalho tem como propósito discutir o dualismo pulsional em Freud, defendendo que a passagem de um dualismo a outro não se configura enquanto uma ruptura em sua teoria, mas sim enquanto movimento em seu pensamento. Para isso, partimos da análise do conceito de pulsão, marcando sua especificidade quando comparada ao instinto animal e apresentando de que maneira as pulsões sexuais e as pulsões de autoconservação possibilitaram o aparecimento de dois modos diferentes de processar a energia psíquica. Em seguida, tratamos do conflito psíquico que se inicia com o processo de recalque e tem como pano de fundo o duelo travado entre a sexualidade e a autoconservação, assunto que nos interessa, pois veremos como a clínica e seus impasses acabam por trazer problemas à primeira teoria pulsional. Por este motivo, trataremos das dificuldades trazidas pelas parafrenias e pelo conceito de narcisismo que acabam por esfumaçar o primeiro dualismo. Por fim, veremos como a neurose traumática e a compulsão à repetição trazem elementos novos à Freud e culminam na elaboração de uma nova definição do pulsional, que agora será pensado também a partir da disputa travada entre as pulsões de vida e as pulsões de morte.

abstract: Toward the ambitious long-term goal of a fleet of cooperating Flexible Autonomous Machines operating in an uncertain Environment (FAME), this thesis addresses several critical modeling, design and control objectives for ground vehicles. One central objective was to show how off-the-shelf (low-cost) remote-control (RC) “toy” vehicles can be converted into intelligent multi-capability robotic-platforms for conducting FAME research. This is shown for two vehicle classes: (1) six differential-drive (DD) RC vehicles called Thunder Tumbler (DDTT) and (2) one rear-wheel drive (RWD) RC car called Ford F-150 (1:14 scale). Each DDTT-vehicle was augmented to provide a substantive suite of capabilities as summarized below (It should be noted, however, that only one DDTT-vehicle was augmented with an inertial measurement unit (IMU) and 2.4 GHz RC capability): (1) magnetic wheel-encoders/IMU for(dead-reckoning-based) inner-loop speed-control and outer-loop position-directional-control, (2) Arduino Uno microcontroller-board for encoder-based inner-loop speed-control and encoder-IMU-ultrasound-based outer-loop cruise-position-directional-separation-control, (3) Arduino motor-shield for inner-loop motor-speed-control, (4)Raspberry Pi II computer-board for demanding outer-loop vision-based cruise- position-directional-control, (5) Raspberry Pi 5MP camera for outer-loop cruise-position-directional-control (exploiting WiFi to send video back to laptop), (6) forward-pointing ultrasonic distance/rangefinder sensor for outer-loop separation-control, and (7) 2.4 GHz spread-spectrum RC capability to replace original 27/49 MHz RC. Each “enhanced”/ augmented DDTT-vehicle costs less than 􀀀175 but offers the capability of commercially available vehicles costing over 􀀀500. Both the Arduino and Raspberry are low-cost, well-supported (software wise) and easy-to-use. For the vehicle classes considered (i.e. DD, RWD), both kinematic and dynamical (planar xy) models are examined. Suitable nonlinear/linear-models are used to develop inner/outer-loopcontrol laws. All demonstrations presented involve enhanced DDTT-vehicles; one the F-150; one a quadrotor. The following summarizes key hardware demonstrations: (1) cruise-control along line, (2) position-control along line (3) position-control along curve (4) planar (xy) Cartesian stabilization, (5) cruise-control along jagged line/curve, (6) vehicle-target spacing-control, (7) multi-robot spacing-control along line/curve, (8) tracking slowly-moving remote-controlled quadrotor, (9) avoiding obstacle while moving toward target, (10) RC F-150 followed by DDTT-vehicle. Hardware data/video is compared with, and corroborated by, model-based simulations. In short, many capabilities that are critical for reaching the longer-term FAME goal are demonstrated. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2015

A utilização de tecnologias de visualização tridimensional aplicada à área de Transportes tem contribuído não só para avaliar o impacto de um projeto de rodovia na região de seu entorno, mas também, no desenvolvimento e estudo dos elementos do próprio projeto geométrico. A pesquisa busca avaliar o potencial do uso de ferramentas de visualização tridimensional (3D) na detecção de deficiências de coordenação entre os alinhamentos horizontal e vertical de um projeto rodoviário. A avaliação foi conduzida por meio de testes com grupos de indivíduos (estudantes do curso de Engenhara Civil sem experiência na área de desenvolvimento de projeto geométrico de rodovias). Estes indivíduos avaliaram trechos de vias em duas situações distintas com correta coordenação dos alinhamentos verticais e horizontais e posteriormente com distorção desta coordenação. Foi utilizado um software aplicativo na área de projeto geométrico de vias terrestre que permite criar um vídeo do drive through da via em questão. Em seguida os avaliadores responderam a um questionário que auxiliou a interpretar os resultados acerca da percepção de deficiências no traçado com a visualização 3D do projeto. Os resultados obtidos foram satisfatórios para o experimento realizado, o que leva a acreditar na possibilidade da introdução dessas ferramentas como parte do curso de engenharia civil, para auxiliar o egresso a desenvolver a habilidade de visualização espacial voltada para a área de projeto geométrico. / The use of three-dimensional visualization technologies applied in the field of transport has contributed not only to assess the impact of a highway project in the region of their surroundings, but also in the development and study of the geometric elements of the project itself. The research seeks to assess the effectiveness of visualization tools-dimensional (3D) in the detection of poor coordination between the horizontal and vertical alignment of a road project. The evaluation will be conducted by testing groups of individuals (students of civil engineering course - no experience in the development of geometric design of highways). These individuals evaluated stretches of roads in two different situations - with proper coordination of horizontal and vertical alignment and then with distortion of this coordination. We used a software application in the geometric design of roads that allows you to create a video drive through of the route in question. Then the evaluators responded to a questionnaire that helped interpret the results on the perception of disability in stroke with 3D visualization of the project. The results were satisfactory for the experiment which leads to believe in the possibility of introducing these tools as part of the civil engineering course, to assist the graduates to develop the skill of spatial visualization focused on the area of geometric design.

This Master's Thesis focuses on the creation of business plan for the establishment of travel agency specialized in outbound tourism. The theoretical part introduces readers with the most definitions in such fields like business, business plan, legislation related to the travel agencies and principal definitions of tourism. The practical part proceeds from the knowledge gained in theoretical part and introduces the real business plan and verify feasibility of establishment and viability in the Czech travel agencies market. Evaluation of business plan viability was made by financial analysis, composition of SWOT analysis and calculation of break even point.