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Industrial applications increasingly require actuators that offer a combination of high force output, large stroke and high accuracy. The ElectroHydraulic Actuator (EHA) was designed by Drs. Habibi and Goldenberg originally as a high-performance actuator for use in robotics. However, it was determined that the EHA had the potential to achieve high positional accuracy. Little research has been performed in the area of high-accuracy hydraulic positioning systems. Therefore, the objective of this study to achieve nano-scale positional accuracy with the EHA while maintaining large stroke and high force output. It was planned to achieve this objective through modification of the prototype EHA and the use of fuzzy control. During this research project, both hardware and control system modifications to the EHA were performed. A high-precision optical encoder position sensor with a 50 nm resolution was mounted on the inertial load to directly measure the position of the load. A number of device drivers were written to interface the MATLAB real-time control environment with the optical encoder and servo motor amplifier. A Sugeno-inference fuzzy controller was designed and implemented in MATLAB. For comparison purposes, a switched-gain controller and a proportional controller were also implemented in the control environment. The performance of the fuzzy controller was compared to the switched-gain controller and the proportional controller in a number of tests. First, the regulatory and tracking performance of the EHA with an inertial load of 20 kg was examined. It was determined in the regulatory tests that the positional accuracy of the EHA with the fuzzy controller was excellent, achieving a steady state error of 50 ± 25 nm or less for step inputs in the range 5 cm to 200 nm. The positional accuracy during the tracking tests was found to be reduced compared to the regulatory tests since the actuator did not have sufficient time to settle to final accuracy due to the timevarying input signals. In all cases, it was found that the positional accuracy of the EHA with the fuzzy controller was significantly greater than with the switched-gain and proportional controllers for both regulatory and tracking signals. Testing with the inertial load eliminated or changed was not performed because the position sensor was mounted to the load, making it unfeasible to alter the load during the time frame of this study. The regulatory and tracking performance of the EHA with an inertial load of 20 kg plus external resistive loads of 90 to 280 N were investigated. It was found that the positional accuracy of the EHA decreased with the application of an external load to 3.10 ± 0.835 µm for a 1 cm step input (90 N load) and 8.45 ± 0.400 µm for a 3 cm step input (280 N load). Again, the positional accuracy of the EHA decreased during the tracking tests relative to the regulatory tests, for the reason stated above. This implies that the positional accuracy of the EHA with a resistive load is in the microscale, rather than the nano-scale as was put forth as the objective of this study. Nevertheless, the positional accuracy of the EHA with the fuzzy controller was found to be significantly greater than with the switched-gain and proportional controllers. It is postulated that the increase in positional error observed during the external load tests was due to an increase in cross-port leakage, relative to the inertial load tests, caused by the pressure differential induced across the actuator by the external load. Methods of reducing the increase in positional error caused by external loads on the EHA remains an area for future study.

This thesis presents the results of three complementary studies which were carried out to evaluate the accuracy of diagnostic tests for Salmonella in pigs. First, a research synthesis method approach, which included a systematic review, meta-analysis and meta-regression, was used to map out existing primary research investigating the accuracy of bacterial culture, antibody or antigen -capture ELISA, and PCR for Salmonella in pigs under field conditions.. Large statistical variability, limited methodological soundness and reporting precluded a quantitative synthesis of findings from multiple studies. The meta-regression identified significant factors, such as variations in test protocols, which explained much of the variability of reported estimates of test accuracy. The need for consistent use of a standard reference test is essential to ensure comparability of results generated in future studies.<p> In the second study, the accuracy of a bacterial culture, real-time (RT) PCR, and a mix-ELISA for Salmonella in were evaluated in western Canadian nursery and grow-finish pigs using traditional and Bayesian statistical methods. Ten farrow-to-finish pig farms from Alberta and Saskatchewan were purposively selected based on their presumptive Salmonella status. Bacteriological culture, RT-PCR and a mix-ELISA were performed on feces and blood samples collected from grow-finish (n=294) pigs and pens. Bayesian estimates of test sensitivity (Se) and specificity (Sp) at the individual pig level were similar to traditional statistical estimates. Sensitivity of culture and RT-PCR ranged from 65-75%, PCR Sp was 98-99% and ELISA Se and Sp at a cutoff of OD¡Ý20% ranged from 59-63% and 84-87%, respectively. In the third study, Salmonella serovar distribution and risk factors for Salmonella shedding were investigated in breeding, nursery, and grow-finish pigs using the same 10 herds. Among 418 Salmonella isolates, most common serovars were Derby (28.5%), Typhimurium, var. Copenhagen (19.1%), and Putten (11.8%). More Salmonella were detected in pooled pen than individual pig samples, confirming that the use of pooled samples is more effective for detecting the full range of serovars that may be present on Canadian pig farms. Sows shed significantly more Salmonella than nursery or grow to finish pigs, suggesting that the breeding herd is an important source of Salmonella persistence. Pelleted feed and nose-to-nose pig contact through pens were also associated with increased Salmonella prevalence, indicating that these factors are relevant as control targets.<p> The main advantages of research synthesis methods are increased power and precision in effect estimates and identification knowledge gaps and areas requiring further research. Bayesian methods for evaluating test accuracy are useful when there is no known "gold standard", which is often the case for zoonotic and food-borne pathogens. Both research synthesis and Bayesian methods are valuable tools for evaluating diagnostic test accuracy and should be more frequently used when developing monitoring and control programs in food safety.

During the 2nd generation Global System for Mobile Communications (GSM) mobile communication, the focus of the mobile positioning was mostly on call setup and messaging. But the evolution of the 3rd generation Wideband Code Division Multiple Access (WCDMA) has changed the focus of mobile positioning. With the increase use of smart phones the mobile positioning is now extensively used for location based services (LBS’s). Mobile positioning becomes extremely important when the user requests any particular LBS, because it directly affects the communication and resource handling between the network and the mobile user MU. In order to reduce cost of messages exchange between the network and the MU it is really important that network should know the location of MU with minimum error. There are many positioning methods that are used today for MU location estimation. In this thesis database correlation method (DCM) is used as a positioning technique to estimate the MU location in the Universal Mobile Telecommunication System UMTS network. The thesis will also explain different penalty techniques for different scenarios that could be used to improve the MU location accuracy in the urban environment. By applying different penalty techniques the best positioning accuracy achieved for 67% of the measurements varies is 88m and for 95% it is 153m. Other penalty techniques results will be compared at the end in order to find the best penalty techniques that offer much improved location accuracy for MU.

Industrial applications increasingly require actuators that offer a combination of high force output, large stroke and high accuracy. The ElectroHydraulic Actuator (EHA) was designed by Drs. Habibi and Goldenberg originally as a high-performance actuator for use in robotics. However, it was determined that the EHA had the potential to achieve high positional accuracy. Little research has been performed in the area of high-accuracy hydraulic positioning systems. Therefore, the objective of this study to achieve nano-scale positional accuracy with the EHA while maintaining large stroke and high force output. It was planned to achieve this objective through modification of the prototype EHA and the use of fuzzy control. During this research project, both hardware and control system modifications to the EHA were performed. A high-precision optical encoder position sensor with a 50 nm resolution was mounted on the inertial load to directly measure the position of the load. A number of device drivers were written to interface the MATLAB real-time control environment with the optical encoder and servo motor amplifier. A Sugeno-inference fuzzy controller was designed and implemented in MATLAB. For comparison purposes, a switched-gain controller and a proportional controller were also implemented in the control environment. The performance of the fuzzy controller was compared to the switched-gain controller and the proportional controller in a number of tests. First, the regulatory and tracking performance of the EHA with an inertial load of 20 kg was examined. It was determined in the regulatory tests that the positional accuracy of the EHA with the fuzzy controller was excellent, achieving a steady state error of 50 ± 25 nm or less for step inputs in the range 5 cm to 200 nm. The positional accuracy during the tracking tests was found to be reduced compared to the regulatory tests since the actuator did not have sufficient time to settle to final accuracy due to the timevarying input signals. In all cases, it was found that the positional accuracy of the EHA with the fuzzy controller was significantly greater than with the switched-gain and proportional controllers for both regulatory and tracking signals. Testing with the inertial load eliminated or changed was not performed because the position sensor was mounted to the load, making it unfeasible to alter the load during the time frame of this study. The regulatory and tracking performance of the EHA with an inertial load of 20 kg plus external resistive loads of 90 to 280 N were investigated. It was found that the positional accuracy of the EHA decreased with the application of an external load to 3.10 ± 0.835 µm for a 1 cm step input (90 N load) and 8.45 ± 0.400 µm for a 3 cm step input (280 N load). Again, the positional accuracy of the EHA decreased during the tracking tests relative to the regulatory tests, for the reason stated above. This implies that the positional accuracy of the EHA with a resistive load is in the microscale, rather than the nano-scale as was put forth as the objective of this study. Nevertheless, the positional accuracy of the EHA with the fuzzy controller was found to be significantly greater than with the switched-gain and proportional controllers. It is postulated that the increase in positional error observed during the external load tests was due to an increase in cross-port leakage, relative to the inertial load tests, caused by the pressure differential induced across the actuator by the external load. Methods of reducing the increase in positional error caused by external loads on the EHA remains an area for future study.

This thesis presents the results of three complementary studies which were carried out to evaluate the accuracy of diagnostic tests for Salmonella in pigs. First, a research synthesis method approach, which included a systematic review, meta-analysis and meta-regression, was used to map out existing primary research investigating the accuracy of bacterial culture, antibody or antigen -capture ELISA, and PCR for Salmonella in pigs under field conditions.. Large statistical variability, limited methodological soundness and reporting precluded a quantitative synthesis of findings from multiple studies. The meta-regression identified significant factors, such as variations in test protocols, which explained much of the variability of reported estimates of test accuracy. The need for consistent use of a standard reference test is essential to ensure comparability of results generated in future studies.<p> In the second study, the accuracy of a bacterial culture, real-time (RT) PCR, and a mix-ELISA for Salmonella in were evaluated in western Canadian nursery and grow-finish pigs using traditional and Bayesian statistical methods. Ten farrow-to-finish pig farms from Alberta and Saskatchewan were purposively selected based on their presumptive Salmonella status. Bacteriological culture, RT-PCR and a mix-ELISA were performed on feces and blood samples collected from grow-finish (n=294) pigs and pens. Bayesian estimates of test sensitivity (Se) and specificity (Sp) at the individual pig level were similar to traditional statistical estimates. Sensitivity of culture and RT-PCR ranged from 65-75%, PCR Sp was 98-99% and ELISA Se and Sp at a cutoff of OD¡Ý20% ranged from 59-63% and 84-87%, respectively. In the third study, Salmonella serovar distribution and risk factors for Salmonella shedding were investigated in breeding, nursery, and grow-finish pigs using the same 10 herds. Among 418 Salmonella isolates, most common serovars were Derby (28.5%), Typhimurium, var. Copenhagen (19.1%), and Putten (11.8%). More Salmonella were detected in pooled pen than individual pig samples, confirming that the use of pooled samples is more effective for detecting the full range of serovars that may be present on Canadian pig farms. Sows shed significantly more Salmonella than nursery or grow to finish pigs, suggesting that the breeding herd is an important source of Salmonella persistence. Pelleted feed and nose-to-nose pig contact through pens were also associated with increased Salmonella prevalence, indicating that these factors are relevant as control targets.<p> The main advantages of research synthesis methods are increased power and precision in effect estimates and identification knowledge gaps and areas requiring further research. Bayesian methods for evaluating test accuracy are useful when there is no known "gold standard", which is often the case for zoonotic and food-borne pathogens. Both research synthesis and Bayesian methods are valuable tools for evaluating diagnostic test accuracy and should be more frequently used when developing monitoring and control programs in food safety.

A large discrepancy between national exam results and final grades in English has been found in compulsory school. Between 1.9% and 18.7%, depending on which school, of students receive a course grade that is different from their grade on the national exam. (Corren, 2001 and Skolvärlden, 2012) As a result, many students have not in reality reached the criteria for the passing grade. In my experience, many students come to us with low self-esteem and motivation due to their difficulties with learning a second language. This study compares two ways of learning and their effects on self-esteem, motivation, accuracy and fluency. The subjects were all the students in the college that started year one, and on paper had the grade pass from compulsory school, but in reality had not reached that level. The students were divided into two groups, one with focus on accuracy, and one with focus on fluency. The accuracy-based task followed the style of a traditional English course book. The fluency-based task had one part where the students told each other about various topics and another where they were encouraged to practice their writing skills by keeping a journal. The students were assessed using one evaluation test, a questionnaire and a final test. The questionnaire provided data for the students’ perceived change in fluency, accuracy, self-esteem and motivation. The written tests provided data for accuracy and fluency. The results in this study showed an overall increase in accuracy, fluency and self-confidence in the accuracy-based task, but that only the fluency-based task enhanced motivation.

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High-quality short-term forecasts of wind speed are vital to making wind power a more reliable energy source. Gneiting et al. (2006) have introduced a model for the average wind speed two hours ahead based on both spatial and temporal information. The forecasts produced by this model are accurate, and subject to accuracy, the predictive distribution is sharp, i.e., highly concentrated around its center. However, this model is split into nonunique regimes based on the wind direction at an off-site location. This work both generalizes and improves upon this model by treating wind direction as a circular variable and including it in the model. It is robust in many experiments, such as predicting at new locations. This is compared with the more common approach of modeling wind speeds and directions in the Cartesian space and use a skew-t distribution for the errors. The quality of the predictions from all of these models can be more realistically assessed with a loss measure that depends upon the power curve relating wind speed to power output. This proposed loss measure yields more insight into the true value of each model's predictions. One method of evaluating time series forecasts, such as wind speed forecasts, is to test the null hypothesis of no difference in the accuracy of two competing sets of forecasts. Diebold and Mariano (1995) proposed a test in this setting that has been extended and widely applied. It allows the researcher to specify a wide variety of loss functions, and the forecast errors can be non-Gaussian, nonzero mean, serially correlated, and contemporaneously correlated. In this work, a similar unconditional test of forecast accuracy for spatial data is proposed. The forecast errors are no longer potentially serially correlated but spatially correlated. Simulations will illustrate the properties of this test, and an example with daily average wind speeds measured at over 100 locations in Oklahoma will demonstrate its use. This test is compared with a wavelet-based method introduced by Shen et al. (2002) in which the presence of a spatial signal at each location in the dataset is tested.

Rotary tables are generally regarded as the forth axis of machining tools. Traditionally, gear sets are used as reducers in the rotary tables. In order to improve the positioning accuracy, load and efficiency of rotary tables, a rotary table which applies the roller gear cam reducer is proposed. From the deduction of the theory, applications of roller gear cam reducers in the industries can be achieved. This thesis is focused on developing the procedure as follows: Firstly, the type of roller gear cam reducer and design parameters are identified. Secondly, the mechanical characteristics of the device are analyzed. Finally, a rotary table is designed and implemented to investigate the performance of the of the roller gear cam rotary table.