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The objective of this project was to design and implement an experimental hydraulic system that simulates joint flexibility of a single rigid link flexible joint robot manipulator, with the ability of changing the joint flexibilitys parameters. Such a system could facilitate future control studies of robot manipulators by reducing investigation time and implementation cost of research. It could also be used to test the performance of different strategies to control the movement of flexible joint manipulators.<p>A hydraulic rotary servo motor was used to simulate the action of a flexible joint robot manipulator. It was a challenging task, since the control of angular acceleration was required. <p>A single-rigid-link, elastic-joint robot manipulator was mathematically modeled and implemented using Matlab. Joint flexibility parameters such as stiffness and damping, could be easily changed. This simulation was considered as a function generator to drive the hydraulic flexible joint robot. In this study the desired angular acceleration of the manipulator was used as the input to the hydraulic rotary motor and the objective was to make the hydraulic system follow the desired acceleration in the frequency range specified. The hydraulic system consisted of a servovalve and rotary motor. <p>A hydraulic actuator robot was built and tested. The results indicated that if the input signal had a frequency in the range of 5 to 15 Hz and damping ratio of 0.1, the experimental setup was able to reproduce the input signal with acceptable accuracy. Because of the inherent noise associated with the measurement of acceleration and some severe non-linearities in the rotary motor, control of the experimental test system using classical methods was not as successful as had been anticipated. This was a first stage in a series of studies and the results provide insight for the future application of more sophisticated control schemes.<p>

The objective of this project was to design and implement an experimental hydraulic system that simulates joint flexibility of a single rigid link flexible joint robot manipulator, with the ability of changing the joint flexibilitys parameters. Such a system could facilitate future control studies of robot manipulators by reducing investigation time and implementation cost of research. It could also be used to test the performance of different strategies to control the movement of flexible joint manipulators.<p>A hydraulic rotary servo motor was used to simulate the action of a flexible joint robot manipulator. It was a challenging task, since the control of angular acceleration was required. <p>A single-rigid-link, elastic-joint robot manipulator was mathematically modeled and implemented using Matlab. Joint flexibility parameters such as stiffness and damping, could be easily changed. This simulation was considered as a function generator to drive the hydraulic flexible joint robot. In this study the desired angular acceleration of the manipulator was used as the input to the hydraulic rotary motor and the objective was to make the hydraulic system follow the desired acceleration in the frequency range specified. The hydraulic system consisted of a servovalve and rotary motor. <p>A hydraulic actuator robot was built and tested. The results indicated that if the input signal had a frequency in the range of 5 to 15 Hz and damping ratio of 0.1, the experimental setup was able to reproduce the input signal with acceptable accuracy. Because of the inherent noise associated with the measurement of acceleration and some severe non-linearities in the rotary motor, control of the experimental test system using classical methods was not as successful as had been anticipated. This was a first stage in a series of studies and the results provide insight for the future application of more sophisticated control schemes.<p>

Proton Exchange Membrane (PEM) fuel cells are becoming an increasingly important alternative to combustion engines as the fossil fuel reserves are depleted. Several papers have presented steady state analyses of the system, but few are known to present dynamic analysis of the flow and control of the hydrogen delivery process. This thesis presents the dynamic analysis of hydrogen delivery to a PEM fuel cell system. The hydrogen is delivered to the anode with use of an ejector for passive recirculation. The system to be studied consists of the manifolds, ejector, and pressure control valve. Models describing the elements of the anode delivery systems are formulated. The governing nonlinear equations are solved analytically and numerically, and the regimes of stable hydrogen delivery process are established. The linearized models are used for performance analysis and optimization of the hydrogen delivery process. The nonlinear model is used to improve the simulation of the dynamics of the PEM fuel cell system and validate the parameters at optimal linearized stability. Experiments are conducted to find the parameters used in the model, as well as validate the results. Both the linear and nonlinear models are implemented in Simulink and tested against the laboratory data from the PEM fuel cell system. The analysis showed that the models have the same time constant and dynamic behavior as the PEM system. The optimal parameters for stability and a faster response with no oscillations in the output are obtained. The redesigned valve and resulting dynamics of the PEM fuel cell system provides improved system performance.

This research is focused on developing a control scheme for regulating the pressure in the brake chamber of an air brake system found in most commercial vehicles like trucks, tractor-trailers and buses. Such a control scheme can be used for providing the ground work for future systems such as forward collision avoidance systems, advanced anti-lock brake systems and differential braking systems. The development of this controller involves two tasks. The first task was the development of a control scheme for achieving the desired pressure in the brake chamber. This scheme was based on a mathematical model of the treadle valve of the air brake system. The second task was the implementation of this control scheme on the experimental facility that was set up at Texas A&M University. The results indicate successful control of a desired brake chamber pressure for a demonstrated range of controller gains.

The thesis offers the following contributions to the epidemiology of hypertension in Canada: 1.The first manuscript uses cross-sectional data from the 2007-2009 Canadian Health Measures Survey (CHMS) to compare the prevalence of controlled hypertension between people with and without diabetes. Of the 74% of Canadians with diabetes who had hypertension, 56% (95% CI: 45%-66%) had controlled blood pressure compared to 64% (95% CI: 58%-69%) of Canadians without diabetes. Among people taking medication, individuals with diabetes were less likely to have controlled hypertension (ORadjusted: 0.3; 95% CI: 0.2-0.6). 2.The objective of the second manuscript was to determine, among Canadians with hypertension, whether individuals with diabetes were less likely than those without to recall health professional advice for healthy behaviours and whether receipt of such advice influences behaviour, using cross-sectional data from the 2009 Survey on Living with Chronic Diseases in Canada (SLCDC). Canadians with diabetes were more likely than those without to recall advice to control/lose weight (81% vs. 66%), exercise (79% vs. 68%), limit alcohol (78% vs. 55%) and modify diet (70% vs. 61%) but not limit salt (65% vs. 64%). Both groups were equally likely to report following advice, with receipt of advice positively associated with engagement in healthy behaviours. 3. The third manuscript describes knowledge of blood pressure targets in Canadians with hypertension using cross-sectional data from the 2009 SLCDC. Knowledge of blood pressure targets was low, with 28% and 32% of Canadians with and without diabetes reporting having discussed a blood pressure target and reporting a target in line with clinical practice guidelines. 4.The fourth manuscript validates an existing self-reported blood pressure control question in a sample of 161 patients with hypertension in Kingston. In people with and without diabetes, the question had sensitivities of 83% ± 11% and 78% ± 10% and specificities of 30% ±19% and 58% ± 21%, respectively. 5.The final manuscript tests a method designed to account for misclassification in epidemiologic studies, using data from the CHMS. The method was found to perform inconsistently in multivariate contexts and introduced bias when minor differential misclassification was ignored. / Thesis (Ph.D, Community Health & Epidemiology) -- Queen's University, 2013-11-14 09:55:12.161

The thesis offers the following contributions to the epidemiology of hypertension in Canada: 1.The first manuscript uses cross-sectional data from the 2007-2009 Canadian Health Measures Survey (CHMS) to compare the prevalence of controlled hypertension between people with and without diabetes. Of the 74% of Canadians with diabetes who had hypertension, 56% (95% CI: 45%-66%) had controlled blood pressure compared to 64% (95% CI: 58%-69%) of Canadians without diabetes. Among people taking medication, individuals with diabetes were less likely to have controlled hypertension (ORadjusted: 0.3; 95% CI: 0.2-0.6). 2.The objective of the second manuscript was to determine, among Canadians with hypertension, whether individuals with diabetes were less likely than those without to recall health professional advice for healthy behaviours and whether receipt of such advice influences behaviour, using cross-sectional data from the 2009 Survey on Living with Chronic Diseases in Canada (SLCDC). Canadians with diabetes were more likely than those without to recall advice to control/lose weight (81% vs. 66%), exercise (79% vs. 68%), limit alcohol (78% vs. 55%) and modify diet (70% vs. 61%) but not limit salt (65% vs. 64%). Both groups were equally likely to report following advice, with receipt of advice positively associated with engagement in healthy behaviours. 3. The third manuscript describes knowledge of blood pressure targets in Canadians with hypertension using cross-sectional data from the 2009 SLCDC. Knowledge of blood pressure targets was low, with 28% and 32% of Canadians with and without diabetes reporting having discussed a blood pressure target and reporting a target in line with clinical practice guidelines. 4.The fourth manuscript validates an existing self-reported blood pressure control question in a sample of 161 patients with hypertension in Kingston. In people with and without diabetes, the question had sensitivities of 83% ± 11% and 78% ± 10% and specificities of 30% ±19% and 58% ± 21%, respectively. 5.The final manuscript tests a method designed to account for misclassification in epidemiologic studies, using data from the CHMS. The method was found to perform inconsistently in multivariate contexts and introduced bias when minor differential misclassification was ignored. / Thesis (Ph.D, Community Health & Epidemiology) -- Queen's University, 2013-11-14 09:55:12.161

Abstract Circulating Fluidized Bed (CFB) boilers are widely used for multi-fuel combustion of waste and bio-fuels. When several non-homogeneous fuels, having varying heat values, are burned simultaneously, the boiler control system can be affected by various control challenges, especially since it is not feasible to reliably measure the energy content of the multi-fuel flow. In order to fulfill energy production needs and maintain the ability to burn low grade fuels, co-firing with high heat value fuels such as gas, oil or coal is needed. Fuzzy Logic Control (FLC) has been successfully used for solving control challenges, where operators' process expertise can be transformed into automation. Real life control objects are often non-linear because the dynamics change with the operating point, or there might be other essential non-linearities in the combustion process. The proposed fuzzy control applications were developed to solve control challenges the operators meet in daily operation of a 150 MW(th) CFB at Varenso Oy's (Stora Enso Oyj) K6 boiler in Varkaus Finland. Before implementing the applications in the fullscale boiler, they were tested at a 2 MW(e) pilot plant boiler at Foster Wheeler Energia Oy's Research Center in Karhula, Finland. According to the industrial experiments, the four applications (steam pressure control, compensation of fuel quality fluctuation, fuel-feed optimization and increased bed inventory monitoring) discussed in this thesis, showed satisfactory performance and various improvements to the boiler control were achieved. Fuzzy logic control was shown to be a notable tool to improve the multi-fuel CFB boiler control.

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