<p>In this thesis, a human-in-the-loop control system is presented to assist an operator in teleoperation of a mobile robot. In a conventional teleoperation paradigm, the human operator would directly navigate the robot without any assistance which may result in poor performance in complex and unknown task environments due to inadequacy of visual feedback. The proposed method in this thesis builds on an earlier general control framework that systematically combines teleoperation and autonomous control subtasks. In this approach, the operator controls the mobile robot (slave) using a force-feedback haptic interface (master). Teleoperation control commands coordinate master and slave robots while an autonomous control subtask helps the operator avoid collisions with obstacles in the robot task environment by providing corrective force feedback. The autonomous collision avoidance is based on a Model Predictive Control (MPC) philosophy. The autonomous subtask control commands are generated by formulating and solving a constrained optimization problem over a rolling horizon window of time into the future using system models to predict the operator force and robot motion. The goal of the optimization is to prevent collisions within the prediction horizon by applying corrective force feedback, while minimizing interference with the operator teleoperation actions. It is assumed that the obstacles are stationary and sonar sensors mounted on the mobile robot measure the obstacle distances relative to the robot. Two formulation of MPC-based collision avoidance are proposed. The first formulation directly incorporates raw observation points as constraints in the MPC optimization problem. The second formulation relies on a line segment representation of the task environment. This thesis employs the well-known Hough transform method to effectively transform the raw sensor data into line segments. The extracted line segments constitute a compact model for the environment that is used in the formulation of collision constraints. The effectiveness of the proposed model-predictive control obstacle avoidance schemes is demonstrated in teleoperation experiments where the master robot is a 3DOF haptic interface and the slave is a P3-DX mobile robot equipped with eight (8) sonar sensors at the front.</p> / Master of Applied Science (MASc)

<p>This thesis tackles the behavior of two planar shaped opposing air jets. The word opposing means that the two air jets are positioned against each other to have a common center-line so that they impinge on each other. Opposing planar jets have several applications in industry which include: galvanization, chemical mixing processes, and combustion. Opposing planar jets are found to produce high level low frequency acoustic tones. In this study, the acoustic response of the opposing planar jets is investigated for different operating conditions. Acoustic tone analysis is performed for a wide range of jet exit velocities and separation distances between the two jets. Results show that the jets produce strong acoustic tones over the whole investigated range of test conditions. The acoustic response depends on the operating conditions of the jets and the acoustic tone is found to be generated by a self-sustained flow oscillation of the two jets.</p> <p>In order to further understand the reported oscillation phenomenon, particle image velocity (PIV) is utilized. Images of the oscillating flow field are acquired and image analysis is performed to obtain various flow dynamic properties. A computational fluid dynamics simulation is performed to help in highlighting the oscillation behavior of the jets. Results reveal that the jets exhibit anti-symmetric ‘’flapping’’ oscillation behavior. The jets are found to initially deflect away from their common centerline due to high stagnation pressure in the impingement region, while they deflect back to their common centerline due to cross stream oscillating velocity in the entrainment regions around the jets.</p> / Master of Applied Science (MASc)

[pt] Esta dissertação analisa a eficácia dos controles de entrada de capitais em restringir e selecionar fluxos financeiros internacionais. A maior contribuição é o foco nas elisões dos controles realizadas pelo mercado financeiro e seus efeitos limitadores na eficácia das restrições ao capital de curto prazo. Primeiro, apresentamos uma abordagem teórica da questão, discutindo como o controle deveria ser implementado. O modelo tem um arcabouço simples e considera dois tipos de investidores: paciente e impaciente. O primeiro (que se deseja atrair) tem maior interesse no retorno de longo prazo e o segundo (que não se deseja atrair) dá maior valor a ganhos de curto prazo. Mostramos que se o diferencial de juros é endógeno à fixação dos controles, e não há possibilidades de elisão das regulações, então pode ser concebido um mecanismo de taxação à entrada de capitais que induz à opção de investir a longo prazo para ambos os investidores, na ausência de crises de confiança. Se vier a se realizar uma probabilidade de default maior que a esperada pelo agente, o investimento será revertido, a não ser que seja oferecido um maior diferencial de taxa de juros. Controles ex-post de saída de capitais também poderiam evitar a reversão do investimento, entretanto, nós não consideramos esta possibilidade devido à grande perda de reputação que ela acarreta. Se o diferencial de taxa de juros for exógeno, como é tipicamente o caso relevante no Brasil, podemos ter um incentivo ao investidor disfarçar seu capital como se fosse de longo prazo mesmo quando já espera sacar no curto prazo. Prosseguimos a análise focando o impacto da capacidade de elisão dos controles pelo mercado. Incorporamos no modelo a elisão às restrições de entrada, mostrando que isto elimina a eficácia dos controles de capitais. Em verdade, as taxas do controle de capitais são determinadas pelo mercado, e então, quanto mais desenvolvido e sofisticado o mercado financeiro do país for, mais ativos substitutos e operações de engenharia financeira podem ser usados para circundar os controles. Fundamentamos nossas conclusões relatando diversas operações de elisão de controles de capitais dos anos noventa, que deixam claro a dificuldade de implementar de facto os controles de capitais. Terminamos a dissertação com uma análise econométrica sobre a duração da eficácia dos controels, via a estimação funções de reposta a impulso. Os resultados indicam que os controles de capitais têm apenas entre dois a seis meses de eficácia em restringir os influxos de capitais financeiros, corroborando a análise dos casos relatados de elisão dos controles. / [en] This thesis analyses the effectiveness of capital inflows controls in changing the size and composition of international financial flows. The major contribution is the focus on capital controls circumvention by the financial market and its limiting impacts on the effectiveness of short-run capital flows restrictions. At first, it is presented a theoretical approach to the question, discussing how it should be implemented. The model has a simple framework and considers two types of financial investors: patient and impatient. The first is more interested in long run returns, and the last gives more value for short run gains. We show that if the interest rate differential is endogenous to the controls fixation, and there is no possibility of regulations´ circumvention, then could be arranged a capital entrance tax scheme that induces the long run investment option for both investors, in absence of a confidence crisis. In occurrence of a higher probability of default than expected by the agent, the investment will be reverted unless higher interest rate differential is provided. Ex-post outflows capital controls could also avoid the investment reversion, nevertheless, we do not consider it here. If the interest rate differential is exogenous, which is typically the relevant case in Brazil, we might see an incentive to the investor to rename its capital as long run even when she expects to reverse the investment in the short run. We continue the analysis focusing the impact of the capacity of capital controls elision by the market. We incorporate in the model the circumvention of the entrance restrictions, showing that it ruins the capital controls effectiveness. In fact, the taxes of the capital controls are really determined by the market, and therefore, as more developed and sophisticated the financial market of the country is, more substitute assets and engineer financial operations can be used to circumvent the control. We underpin our conclusions describing several capital controls elisions operations in Brazil during the nineties, which make clear the difficulties of capital controls de facto implementation. We finish the dissertation with an impulse response function analyses, that indicates that the capital controls have only between two to six months of effectiveness in restricting financial capital inflows.

There is an increasing interest in automated mobile equipment in the construction, agriculture and mining industries to improve productivity, efficiency and operator safety. In general, these machines belong to a class of mobile vehicles with a tool for manipulating its environment to accomplish a repetitive task. Forces and motions are inherently coupled between the tool (<em>e.g.</em> bucket or blade) and the means of vehicle propulsion (<em>e.g</em>. wheels or tracks). Furthermore, they are often operated within uncertain and unstructured environments. A particularly challenging case involves the use of a bulldozer for the removal of excavated material. Modeling and control of mobile robots that interact forcibly with their environment, such as robotic excavation machinery, is a challenging problem that has not been adequately addressed in prior research. This thesis investigates the low-level modeling and control of a 3-DOF robotic bulldozing operation. Motivated by a bulldozing process in an underground mining application, a theoretical nonlinear hybrid dynamic model was developed. The model includes discrete operation modes contained within a hybrid dynamic model framework. The dynamics of the individual modes are represented by a set of linear and nonlinear differential equations. An instrumented scaled-down bulldozer and environment were developed to emulate the full scale operation. Model parameter estimation and validation was completed using experimental data from this system. The model was refined based on a global sensitivity analysis. The refined model was found to be suitable for simulation and design of robotic bulldozing control laws. Optimal blade position control laws were designed based on the hybrid dynamic model to maximize the predicted material removal rate of the bulldozing process. A stability analysis of the underlying deterministic closed-loop process dynamics was performed using Lyapunov’s second method. Monte Carlo simulation was used for further performance and stability analysis of the closed-loop process dynamics including stochastic state disturbances and input constraints. Results of the Monte Carlo simulation were also used for tuning the blade position control laws. Experiments were conducted with the scaled-down robotic bulldozing system. The control laws were implemented with various tuning values. As a comparison, a rule-based blade control algorithm was also designed and implemented. The experimental results with the optimal control laws demonstrated a 33% increase in the average material removal rate compared to the rule-based controller. / Doctor of Philosophy (PhD)

No description available.

Cancer of the prostate (CaP) is the most common malignancy diagnosed in men in the Western society. During the last years, prostate specific antigen (PSA) has been used as a biomarker for CaP, although a high PSA value is not specific for CaP. Thus, there is an urgent need for new and improved diagnostic markers for CaP. In this thesis, the aim was to find a miRNA signature for diagnosis of CaP and to elucidate if differences in behavior between transition zone and peripheral zone tumors are reflected in miRNA expression. One of the major findings is anexpression signature based on nine miRNAs that with high accuracy (85%) could classify normal and malignant tissues from the transition zone of the prostate. The results furthermore show that the major differences in miRNA expression are found between normal and malignant tissues, rather than between the different zones. In addition, tumors arising in the peripheral zone have fewer changes in miRNA expression compared to tumors in the transition zone, indicating that the peripheral zone is more prone to tumor development compared to the transition zone of the prostate. A crucial step in pre-processing of expression data, in order to differentiate true biological changes, is the normalization step. Therefore, an additional aim of this thesis was to compare different normalization methods for qPCR array data in miRNA expression experiments. The results show that data-driven methods based on quantile normalization performs the best. The results also show that in smaller miRNA expression studies, only investigating a few miRNAs, RNU24 is the most suitable endogenous control gene for normalization. Taken together, the results in this thesis show the importance of miRNAs and the possibility of their future use as biomarkers in the field of prostate cancer.

An event-driven, sequential, process control system was designed for International Isotopes, Inc., to automate and remotely control a target station at the company's linear accelerator facility. The designed system consisted of two major sections: a software program (virtual instrument), which was developed by LabVIEW, and a hardware interface (FieldPoint Modular Distributed I/O System by National Instrument), which had to be a pre-developed system that did not require customization. The designed virtual instrument was tested on a simulation model that mimed the target station. The result was a valid design.

Master of Science / Department of Architectural Engineering and Construction Science / Fred L. Hasler / The Internet of Things (IoT) is rapidly growing and is starting to be incorporated into commercial buildings. One of the ways that the IoT is being used in buildings is connected lighting, also referred to as smart lighting. Connected lighting allows for communication between the lighting system, people, the environment, and other devices. This paper will focus on connected lighting and its effect on lighting controls and design. The IoT is expected to see substantial growth in the next few years and the growth of connected devices will have a huge impact on the lighting industry as connected lighting systems will be installed in more commercial buildings. The shift to solid state lighting (SSL) in recent years has brought the transition from conventional lighting controls to connected lighting controls. For this shift to be successful, issues with interoperability, security and reliability will need to be overcome. Connected lighting systems on the market are using both wired and wireless technologies. Power over Ethernet (PoE) and wireless technologies such as ZigBee and Bluetooth Smart are currently being incorporated into connected lighting systems. The introduction of these technologies is changing the way that lighting control systems are designed and installed. Products such as fixture-integrated sensors and wireless devices are also being used in connected lighting systems. These products, along with the wired and wireless technologies, are changing lighting control system configurations. Lighting design will also be affected by connected lighting systems. New features including color-tunability and indoor positioning will be used to enhance the lighting system and improve occupant health. Also, energy code compliance will be easier since connected lighting controls will be mostly software-based and can be reprogrammed. Connected lighting systems will be integrated into other building systems such as heating, ventilating, and air conditioning systems or security systems and will also be used in a variety of applications. Connected lighting systems will greatly affect both lighting controls and design of lighting control systems. This paper introduces connected lighting and is intended for those who are not familiar with its design, applications, and implementation.

What will happen to sport cars once our society and infrastructure allow for a fully autonomous transport systems? My concern for the ”survival of the sports car” clearly originates from an emotional viewpoint rather than a reasonable argument. We know about the benefits that come along with autonomy but that doesn’t make the fear of loosing the emotional side of driving unfounded. My aim was to create a scenario that allows both reason and emotion to coexist and furthermore to benefit from each other rather than to create a conflict. The result is a PORSCHE for 2040 that shows an exciting concept for steering fully autonomous cars of the future. It combines the benefits of autonomy with the emotions of sports cars.

M.Ing. (Transportation) / Consecutive green phases at signalized intersections are separated by an amber and sometimes all-red period to allow a safe changeover from flow in one direction to another. Al though this signal change interval consists of only a few seconds, existing practice in setting this signal change interval varies considerably. Research on this subj ect has focused on understanding how individual drivers react when they are confronted by a change signal. Identifying the factors that describe the need for different change intervals can most easily be determined by measuring the aggregated behaviour of motorists under conditions where these factors vary. Evidence suggests that the South African driver overseas counterpart regarding his attitude towards interval differs from his the signal change Field observations of drivers' aggregated behaviour when confronted by a change interval were made at 17 approaches to 9 different intersections. The linear relationship between the signal change interval and various factors which apparently have an influence on the need for such a period were determined. The regression models were also structured to allow evaluation of existing models such as the well-known ITE-formula. The results were evaluated statistically. It was not possible to calibrate the ITE-formula for South African conditions. The approach adopted here conforms to tiling designs that use a constant (for a specific approach) amber interval. This constant is probably a summation of the influence of all the factors which influence the need for a signal change interval. The use of the clearance time for a crossing, as the all-red period, is also ascertained.