The Virtual Network (VN) protocol is a communications protocol software compatible with the Space Plug-and-play Architecture (SPA). This Master Thesis defines a protocol that extends the Virtual Network protocol to cover communication over the Controller Area Network (CAN). The Virtual Network for the Controller Area Network (VN-CAN) is defined, modelled and verified using UPPAAL as well as implemented and tested while running on actual hardware. The VN-CAN protocol enables components on the CAN network to communicate with other components both inside and outside of the CAN network, which together with the modularity of both the protocol and the implementation enables application level software to be agnostic of their physical position in the network. The implementation enables components to automatically discover routes to other components on the VN network without the need for any prior knowledge about the network topology. A method for direct addressing, i.e. that two components on the CAN network can communicate directly without sending messages via a central router, has been added to the VN-CAN protocol in order to reduce traffic on the CAN network. UPPAAL modelling and verification of the VN-CAN protocol has been done to give a high level of confidence in the correctness of the protocol. Testing on actual hardware has shown that the protocol achieves the goals of address resolution, self addressing and transfer of VN messages over CAN.

The objective of the research is to examine the impact of auditory stimulus on improving reaching performance in children with cerebral palsy. A form of auditory stimulus, called rhythmic auditory stimulation (RAS), is well-established in neurological fields as well as in music-based rehabilitation and therapy. RAS is a method in which the rhythm functions as a sensory cue to induce temporal stability and enhancement of movement patterns by what is believed to be a temporal constraint of the patient’s internal optimized path of motion. In current neurological studies, it is suggested that activity in the premotor cortex may represent the integration of auditory information with temporally organized motor action during rhythmic cuing. Based on this theory, researchers have shown that rhythmic auditory stimulation can produce significant improvement in mean gait velocity, cadence, and stride length in patients with Parkinson’s disease. Evidence validating this observation was also seen in a study on hemiparetic stroke wherein patients displayed improvements in spatio-temporal arm control, reduction in variability of timing and reaching trajectories, and kinematic smoothing of the wrist joint during rhythmic entrainment. Lastly, studies have suggested an accompaniment of sound feedback in addition to visual feedback can result in a positive influence and higher confidence in patients who have had a stroke or spinal cord injury. Although an effect of rhythmic cuing on upper extremity therapy has been explored in areas where brain injury has occurred (such as patients who have incurred stroke, spinal injury, traumatic brain injury, etc.), what has not been explored is the effect of rhythmic cuing on upper extremity therapy for individuals with neurological movement disorders, such as cerebral palsy. Thus, in this research, we set out to explore the effect of RAS in therapeutic interventions for children with cerebral palsy. Through this investigation, we examine its effect on reaching performance as measured through range of motion, peak angular velocity, movement time, path length, spatio-temporal variability, and movement units. For this assessment, we created a virtual system to test the aforementioned principles. We established clinically based angular measurements that include elbow flexion, shoulder flexion, and shoulder abduction using a 3D depth sensor to evaluate relevant metrics in upper extremity rehabilitation. We validated the output of our measurements through a comparison with a Vicon Motion Capture System. We then confirmed the trends of the metrics between groups of adults, children, and children with cerebral palsy. Through testing our system with adults, children, and children with cerebral palsy, we believe we have constructed a system that may induce engagement, which is critical to physical therapy, and may also have a positive impact on the metrics. Although we see trends indicative of an effect through use of the system on children with cerebral palsy, we believe further testing is needed in order to establish or refute the effect and also to definitively establish or refute the effect of rhythmic auditory stimulation. The system, the angular measurements, and the metrics we employ could provide an excellent foundation for future research in this space.

Understanding natural mechanisms of protection against HIV infection and disease progression are key priorities for informing vaccine and microbicide design. The research presented in this thesis aimed to characterize mechanisms of defence in HIV-exposed seronegative (HESN) individuals, who naturally resist infection by HIV, and HIV-controllers, who are HIV-infected, but suppress viral replication in the absence of treatment. Previous studies have linked resistance to HIV infection with low basal levels of gene transcription and reduced production of inflammatory mediators, suggesting an overall state of immune quiescence in HESN. Immune quiescence may also be protective in HIV-infected individuals, as immune activation drives disease progression. The central hypothesis of this thesis is that immune quiescence protects against HIV infection and disease progression by limiting the pool of activated target CD4+ T cells susceptible to HIV infection. This hypothesis was addressed by evaluating immune function in HESN from the Pumwani commercial sex worker cohort and HIV-controllers from the Manitoba elite controller cohort. In HESN, immune quiescence was marked by low levels of circulating activated T cells and low levels of the proinflammatory mediators IL-1α and IL-8 in the cervical mucosa. Regulatory T cells (Tregs), which suppress T cell activation, were elevated in HESN, and may represent a driver of immune quiescence. Low T cell activation and elevated Tregs were associated with reduced cellular susceptibility to infection in vitro. These data suggest that immune quiescence protects against infection by limiting the activated target CD4+ T cell pool, in support of the central hypothesis. HIV-controllers expressed low levels of the proinflammatory chemokines IP-10 and MCP-1 and low frequencies of activated T cells. These data demonstrate that immune quiescence is not only protective prior to exposure, but is also beneficial following infection. HIV-controllers also had elevated MIP-1α, reduced TGFβ and HIV-specific T cell proliferation responses, which contribute to protection by mechanisms other than immune quiescence. Taken together, these data support a role for immune quiescence in protection from HIV infection and disease progression. Mechanisms of reducing inflammation and target cell activation should be considered during future HIV vaccine and microbicide development.

The subject of this thesis is the design and practical application of a model-based controller with variable structure control (VSC). Robot manipulators are highly non-linear systems, however they form a specific class in the non-linear group. Exact mathematical descriptions of the robot dynamics can be achieved and further, robot manipulators have specific useful properties that can be used for the design of advanced controllers. The inclusion of the inverse dynamic description of the robot manipulator as a feedforward term of the controller (model-based controller) is used to transform two non-linear systems i.e. the controller and the robot, into one linear system. The limitation of this technique arises from the accuracy of the inverse dynamic model. The linearisation only takes place if the model is known exactly. To deal with the uncertainties that arise in the model, a control methodology based on variable structure control is proposed. The design of the controller is based on a Lyapunov approach and engineering considerations of the robot. A candidate Lyapunov function of a pseudo-energy form is selected to start the controller design. The general form of the controller is selected to satisfy the negative definiteness of the Lyapunov function. The initial uncertainties between the actual robot dynamics and the model used in the controller are dealt with using a classical VSC regulator. The deficiencies of this approach are evident however because of the chattering phenomenum. The model uncertainties are examined from an engineering point of view and adjustable bounds are then devised for the VSC regulator, and simulations confirm a reduction in the chattering. Implementation on the SPRINTA robot reveals further limitations in the proposed methodology and the bound adjustment is enhanced to take into account the position of the robot and the tracking errors. Two controllers based on the same principle are then obtained and their performances are compared to a PID controller, for three types of trajectory. Tests reveal the superiority of the devised control methodology over the classic PID controller. The devised controller demonstrates that the inclusion of the robot dynamics and properties in the controller design with adequate engineering considerations lead to improved robot responses.

The work presented in this thesis was motivated by the desire to establish an alternative approach to the design of robust polynomial controllers. The procedure of pole-placement forms the basis of the design and for polynomial systems this generally involves the solution of a diophantine equation. This equation has many possible solutions which leads directly to the idea of determining the most appropriate solution for improved performance robustness. A thorough review of many of the aspects of the diophantine equation is presented, which helps to gain an understanding of this extremely important equation. A basic investigation into selecting a more robust solution is carried out but it is shown that, in the polynomial framework, it is difficult to relate decisions in the design procedure to the effect on performance robustness. This leads to the approach of using a state space based design and transforming the resulting output feedback controller to polynomial form. The state space design is centred around parametric output feedback which explicitly represents a set of possible feedback controllers in terms of arbitrary free parameters. The aim is then to select these free parameters such that the closed-loop system has improved performance robustness. Two parametric methods are considered and compared, one being well established and the other a recently proposed scheme. Although the well established method performs slightly better for general systems it is shown to fail when applied to this type of problem. For performance robustness, the shape of the transient response in the presence of model uncertainty is of interest. It is well known that the eigenvalues and eigenvectors play an important role in determining the transient behaviour and as such the sensitivities of these factors to model uncertainty forms the basis on which the free parameters are selected. Numerical optimisation is used to select the free parameters such that the sensitivities are at a minimum. It is shown both in a simple example and in a more realistic application that a significant improvement in the transient behaviour in the presence of model uncertainty can be achieved using the proposed design procedure.

These thesis focus on one of the most problematic fields of the governance of local authorities – the control system of local governments‘ and the most important figure in this system – the municipality controller‘s institution. This work aims to analyse the municipality controller‘s instituttion and to present an in depth and systematic analysis of it‘s legal regulation and institutional development, problems and topicalities, concerning the controller‘s practise and functions. Another aspect of this research - is to describe the international and the EU standards, related to the external and internal audit, and to give examples of the experience of other European countries in the field of the municipality control.

The main objective of this research is the development of a flexible test-bench for evaluation of hybrid electric powertrain controllers. As a case study, a real-time near-optimal powertrain controller for a series hybrid electric vehicle (HEV) has been designed and tests. The designed controller, like many other optimal controllers, is based on a simple model. This control-oriented model aims to be as simple as possible in order to minimize the controller computational effort. However, a simple model may not be able to capture the vehicle's dynamics accurately, and the designed controller may fail to deliver the anticipated behavior. Therefore, it is crucial that the controller be tested in a realistic environment. To evaluate the performance of the designed model-based controller, it is first applied to a high-fidelity series HEV model that includes physics-based component models and low-level controllers. After successfully passing this model-in-the-loop test, the controller is programmed into a rapid-prototyping controller unit for hardware-in-the-loop simulations. This type of simulation is mostly intended to consider controller computational resources, as well as the communication issues between the controller and the plant (model solver). As the battery pack is one of the most critical components in a hybrid electric powertrain, the component-in-the-loop simulation setup is used to include a physical battery in the simulations in order to further enhance simulation accuracy. Finally, the driver-in-the-loop setup enables us to receive the inputs from a human driver instead of a fixed drive cycle, which allows us to study the effects of the unpredictable driver behavior. The developed powertrain controller itself is a real-time, drive cycle-independent controller for a series HEV, and is designed using a control-oriented model and Pontryagin's Minimum Principle. Like other proposed controllers in the literature, this controller still requires some information about future driving conditions; however, the amount of information is reduced. Although the controller design procedure is based on a series HEV with NiMH battery as the electric energy storage, the same procedure can be used to obtain the supervisory controller for a series HEV with an ultra-capacitor. By testing the designed optimal controller with the prescribed simulation setups, it is shown that the controller can ensure optimal behavior of the powertrain, as the dominant system behavior is very close to what is being predicted by the control-oriented model. It is also shown that the controller is able to handle small uncertainties in the driver behavior.

Shape Memory Alloys (SMAs) have been demonstrated to be effective actuator elements in a wide range of applications, such as robotics, medicine, aerospace and automotive. Enabled by the unique thermo-mechanical properties of SMAs, these actuators offer the advantages of light weight, high power-to-weight ratio and a simple actuation mechanism compared to traditional actuator types. At the same time, the widespread adoption of the SMA actuator remains elusive as its low power efficiency and complex hysteretic behaviour often render it an impractical means of actuation. These actuators also exhibit a slow response speed and their response is highly sensitive to changes in the external environment, namely ambient temperature and mechanical stress, thus complicating their control. Position, force or temperature sensors may be used to facilitate feedback control, but at the cost of increasing the overall size and complexity of the system. The difficulties caused by the hysteretic behaviour can be largely avoided when SMA wires are used as on-off actuators, making SMAs well suited for such applications. However, they may still be subject to a wide range of dynamic operating conditions that would impact their actuation time, and achieving a consistent actuation time is often highly desirable. This thesis presents the synthesis of a nitinol SMA actuator control system which uses electrical resistance feedback to enable a fast response speed and robustness to disturbances in the external environment. A study of the resistance behaviour of SMAs is discussed first. The design of an adaptive controller and the experimental evaluation of its performance are described in detail next. The objective of the SMA actuator control system is to achieve a consistent and fast actuation time throughout the range of operating ambient temperature and stress. The control system is implemented experimentally and shown to be quite successful.

The purpose of this thesis was to design controllers by using H1 and &sup1 / control strategies in order to suppress the free and forced vibrations of smart structures. The smart structures analyzed in this study were the smart beam and the smart &macr / n. They were aluminum passive structures with surface bonded PZT (Lead-Zirconate-Titanate) patches. The structures were considered in clamped-free con&macr / guration. The &macr / rst part of this study focused on the identi&macr / cation of nominal system models of the smart structures from the experimental data. For the experimentally identi&macr / ed models the robust controllers were designed by using H1 and &sup1 / -synthesis strategies. In the second part, the controller implementation was carried out for the suppression of free and forced vibrations of the smart structures. Within the framework of this study, a Smart Structures Laboratory was established in the Aerospace Engineering Department of METU. The controller implementations were carried out by considering two di&reg / erent experimental set-ups. In the &macr / rst set-up the controller designs were based on the strain measurements. In the second approach, the displacement measurements, which were acquired through laser displacement sensor, were considered in the controller design. The &macr / rst two &deg / exural modes of the smart beam were successfully controlled by using H1 method. The vibrations of the &macr / rst two &deg / exural and &macr / rst torsional modes of the smart &macr / n were suppressed through the &sup1 / -synthesis. Satisfactory attenuation levels were achieved for both strain measurement and displacement measurement applications.

ABSTRACT DESIGN AND IMPLEMENTATION OF A MICROPROCESSOR BASED DATA COLLECTION AND INTERPRATATION SYSTEM WITH ONBOARD GRAPHICAL INTERFACE G&ouml / ks&uuml / g&uuml / r, G&ouml / khan M.S., Department of Electric and Electronics Engineering Supervisor : Prof. Dr. Hasan Cengiz G&uuml / ran December 2004, 103 pages This thesis reports the design and implementation of a microprocessor based interface unit of a navigation system. The interface unit is composed of a TFT display screen for graphical interface, a Controller Circuit for system control, a keypad interface for external data entrance to the system and a power interface circuit to provide interface between the battery of the navigation system and the Controller Circuit. This thesis reports high speed design of the Controller Circuit and generation of system functions. Main functions of the interface unit are communicating with navigation computer and providing a graphical interface to the driver of the vehicle containing the navigation system. Communication and graphical data preparation functions are implemented through the use of a microprocessor. Driver function of TFT display is implemented through the use of a Field Programmable Gate Array, which is programmed using the Very High Speed IC Description Language (VHDL). Keywords: Navigation System, Interface Unit, Controller Circuit, Image Generation