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The purpose of this PhD Research Study is to investigate the reasons behind the adoption of Public Private Partnerships (PPPs) in Kenya, within the context of sub-Saharan Africa, as a policy option in infrastructure financing. Using Broadbent, Laughlin and Read's (1991) interpretation of Habermas (1984, 1987) as the theoretical framework, the thesis uses the concepts of "steering" and "steering mechanisms" and seeks to determine, at a macro level, why Kenya has decided to adopt the use of PPPs. The Research Methodology used is "middle range thinking" (Laughlin, 1995; Broadbent and Laughlin, 2009). Middle range thinking argues that theory presents the researcher with a "skeletal framework" that can then be "fleshed out" using the empirics (Laughlin, 1995). In this thesis, the skeletal framework is the theoretical framework on steering, advanced by Broadbent, Laughlin and Read (1991). Kenya has been selected as the case study and the use of interviews and documents analysis have been employed as the research methods. This study finds that with a large infrastructure deficit in critical areas, Kenya has decided to employ the use of PPPs to bridge this gap. Moreover, Kenya has also adopted the use of PPPs for macro-economic reasons, the need to provide for services within budgetary constraints and to rein back on the increasing percentage of debt as a proportion of GDP. In addition to economic factors, the empirics suggest that Kenya's PPP policy has been established due to "supranational steering" by the World Bank and its associates through various "steering mechanisms". Through consultations with the Public Private Infrastructure Advisory Facility (PPIAF) of which the Bank is a member, Kenya has been able to establish the PPP regulatory framework and set up its PPP Secretariat. Through funding from the World Bank's Infrastructure Finance Public Private Partnerships (IFPPP) project, Kenya has been able to boost the capacity of the PPP Unit and to roll out its PPP programme. The national government, on the other hand, has carried out societal steering by passing the required PPP laws and creating the necessary institutional framework. This thesis contributes to the increasing literature on why different countries are increasingly adopting the use of PPPs. It also contributes to theory by adding to the concept of "societal steering" (Broadbent, Laughlin and Read, 1991) and suggesting that with respect to PPPs in developing countries, there is also "supranational steering" by the World Bank.

Predatory behaviours are ideal for studying the limits of performance and control within animals. Predation naturally creates a competition between the sensors and physiology of predator and prey. Aerial predation demonstrates the greatest feats of physical performance, demanding the highest speeds and accelerations whilst both predator and prey are free to pitch, yaw, and roll. These high speeds and degrees of rotational freedom make control a complex problem. However, from the perspective of the researcher attempting to decipher the control laws that underpin predator guidance, the question is made more soluble by the predator's fixation on its target. The goal of the pursuer is clear, to contact the target, and thus their systems are focused on the optimization of that action. This is as opposed to more mundane activities, where conflicting interests compete for the attention and behavioural response of the animal. In order to study the necessary trade-offs that underpin aerial predation, this thesis will focus on the hunting behaviour of two fly species. The first is a robber fly, Holcocephala fusca, on which the majority of the first two chapters focus. Secondarily, work with the killer fly Coenosia attenuata will be included in the latter two chapters as a direct contrast to results from Holcocephala. Both are miniature dipteran predators, but not closely related. The structure of this thesis is broken into six chapters, summarised in the following list: 1. Thecompoundeyeofinsectsgenerallyhasmuchpoorerresolutionthanthatofcameratype eyes. Poor resolution is exacerbated in smaller insects that cannot commit the resources required for eyes with large lenses that facilitate high spatial resolution. Holcocephala has developed a small number of facets into a forward-facing acute zone where the spatial acuity is reduced to ~0.28°, rivalling the very best resolution of any compound eye. The only compound eyes with a comparable spatial resolution belong to dragonflies, in excess of an order of magnitude larger than Holcocephala. 2. Numerous potential targets may be airborne within the visual range of a predator. Not all of these may be suitable. Chasing unsuitable targets may waste energy or result in direct harm should they turn out to be larger than the predator can overcome. It is thus a strong imperative for a predator to filter the targets it takes after. Targets silhouetted against the sky display a paucity of cues that a predator could use to determine their size. Holcocephala displays acute size selectivity towards smaller targets. This selectivity goes beyond heuristic rules and size/speed ratios. Instead, Holcocephala appears able to determine absolute size and distance of targets. 3. Both Holcocephala and Coenosia intercept targets, heading for where the target is going to be in the future rather than its current location. Both species plot trajectories in keeping with the guidance law of proportional navigation, an algorithm derived for modern guided missiles. There are key differences evident in the internal physiological constants applied to the control system between the species. These differences are likely linked to the specific environmental conditions and visual physiologies of the flies, especially the range at which targets are attacked. 4. Stemming from the use of the proportional navigational framework, this chapter dives into the intricacies of gain and the weighting of the navigational constant, and the geometric factors that underpin the control effort and eventual success of the control system. 5. "Falcon-diving" can be found in killer flies dropping from their enclosure ceiling, in which they miss targets after diving towards them. Through proportional navigation, it can be demonstrated that the navigational system combined with excessive speed results in acceleration demands the body cannot match. 6. Holcocephala is capable of evading static obstacle whilst intercepting targets. Application of proportional navigation and a secondary obstacle-evasive controller can demonstrate where the fly is combining multiple inputs to guide its heading.

In order to remain competitive in the marketplace, all motor vehicle manufacturers face difficult decisions with regard to balancing cost vs. feature. That is to say that the manufacturer must balance the cost of the product to the customer to remain competitive whilst offering appropriate technology and standard features required by that customer. All motor manufacturers are therefore under pressure to keep costs of nonfeature items to a minimum. One of the cost reductions items prevalent on most vehicles is the deletion of the structural member that attaches the rear bumper, known as the bumper beam (RBB), which is researched in this Thesis. This generates average vehicle savings of $20 and, as this is invisible to the customer, should enable the manufacturers to realise a significant saving or allow this revenue to be spent on additional feature without loss of vehicle function. However, in nearly all cases, deletion of the rear bumper beam has the effect of degrading the steering responses of the vehicle by 1 to 1½ rating points (out of 10), which is contrary to the premise of cost reductions; which is to ensure that vehicle function is unaffected. Initial analysis of vehicles with deleted rear bumper beams cannot show an objective measurable difference in any vehicle behaviours with or without the beam fitted, and hence CAE studies using ADAMS models cannot verify the effects of the bumper beam. It was necessary to employ unconventional modelling and testing methods such as rigid body, flexible body model techniques as well as experimental studies included driving robots and expert driver appraisals. The research demonstrated that vehicle modelling methods currently used, cannot establish or predict the complete vehicle ride and handling status. A total vehicle model approach should be used without separating the body CAE model and vehicle dynamics ADAMS model into separate entities. Furthermore, it was concluded that the determination to the effects of body hysteresis rather than pure stiffness is of crucial importance and that the steering attribute could be maintained with the deletion of the RBB analytically.

In this work torque vectoring methods are used to compensate for a low performance steer-by-wire system. Currently a number of vehicle manufacturers are considering introducing steer-by-wire into their range of vehicles. Some of the key concerns for the manufacturers are safety and cost. The safety can be subdivided in the integrity of the steering system and the effect on handling. The focus of this study is the use of low cost steering actuators on a vehicle and identify its effects on the vehicle's handling response. The test vehicle is dune buggy modified to accommodate the low performance steer-by-wire system without a direct mechanical link between the steering wheel and the wheels and equipped with various sensors to data recording. In order to investigate the influence of torque vectoring system on the steer-by-wire, an eight degrees of freedom vehicle model in Matlab/Simulink has been developed. The eight degrees of freedom are longitudinal and lateral translations, yaw and roll motion and rotation of each wheel. The Matlab/Simulink model also includes the dynamics of the actuators, which is validated against the experimental data. The actuator was shown to have a bandwidth of less than 0.3 Hz. The eight degrees of freedom model's response was validated against experimental data for both steady state and transient response up to 0.5 g. The tyre forces and moments are implemented by using the Dugoff tyre model, which has been validated against experimentally measured data. The torque vectoring system uses the cascade approach based on a reference model, which uses a two degrees of freedom (bicycle model) to generate the reference signal for control purposes. The upper level yaw controller is based on the optimal control theory and uses the LQR (Linear-quadratic regulator) approach. The lower level wheel slip controller is based on a slidingmode structure and prevents tyre force saturation. The simulation results show that the vehicle augmented with the torque vectoring system outperforms the low performance steer-by-wire vehicle and also the vehicle with conventional steering arrangement.

A human brain has billions of processing elements operating simultaneously; the only practical way to model this computationally is with a massively-parallel computer. A computer on such a significant scale requires hundreds of thousands of interconnected processing elements, a complex environment which requires many levels of monitoring, management and control. Management begins from the moment power is applied and continues whilst the application software loads, executes, and the results are downloaded. This is the story of the research and development of a framework of scalable management tools that support SpiNNaker, a novel computing architecture designed to model spiking neural networks of biologically-significant sizes. This management framework provides solutions from the most fundamental set of power-on self-tests, through to complex, real-time monitoring of the health of the hardware and the software during simulation. The framework devised uses standard tools where appropriate, covering hardware up / down events and capacity information, through to bespoke software developed to provide real-time insight to neural network software operation across multiple levels of abstraction. With this layered management approach, users (or automated agents) have access to results dynamically and are able to make informed decisions on required actions in real-time.

Much has been written in recent years about governance in the areas of political science, public policy, local government, and international relations. However, social scientific usage of the governance concept has been eclectic, diverse and at times contradictory (Jessop, 1998: 29) as well as confusing and sometimes misleading. In addition, despite the burgeoning literature on governance, little research effort has to date been devoted to examining the term in relation to the organisation, administration and management of sports organisations. This thesis is concerned with reviewing the range of applications of the concept, and in particular evaluating the utility of governance in understanding aspects of the management and policy process of sport. For the purpose of this study a case study approached is adopted, focusing on three sports: cricket, association football and swimming, and within these the pattern of interrelationships between the government and related agencies, the media and broadcasters, athlete-representative groups and supporter organisations, as well as focusing on issues relating to gender. The study concludes by arguing that governance broadens our conceptual repertoire, introduces greater sensitivity and subtlety into policy analysis, and highlights problems of coordination both in government and across a range of agencies, organisations and policy actors.

Soft vibrational robots are robots that incorporate compliant structures into their design and are driven by oscillating actuators. A recent, popular version of a soft vibrational robot is the bristle bot, which uses flexible bristles and a vibration motor to propel itself across surfaces and through pipes. This motion is primarily driven by stick-slip dynamics resulting from asymmetric frictional forces applied at the bristle tips. Depending on the frequency of vibration of the motor, the robot experiences various resonance regions allowing it to maneuver in different directions. Attaching bristles to all sides of the robot and placing it in a pipe, these resonance regions give the potential for such a robot to navigate a pipe system. While several papers cover the robotics side of this research interest and others the analytical side of a single bristle bot on a flat surface, the dynamics of a bristle bot in a pipe and its ability to steer through pipe bifurcations has little been explored. This thesis aims to cover the process of modeling the nonlinear, stick-slip dynamics of the bristle bot in a pipe and how to use the resonance regions of the system to reliably steer the robot through a pipe system.

As passenger vehicle technologies have advanced, so have their capabilities to avoid obstacles, especially with developments in tires, suspensions, steering, as well as safety technologies like ABS, ESC, and more recently, ADAS systems; however, environments around passenger vehicles have also become more complex, and dangerous. As autonomous road vehicle (ARV) development aims to address these complex environments, one area that is still new and open is ARV emergency obstacle avoidance at highway speeds (55-165 km/h) and on slippery road surfaces. When introducing obstacle avoidance capabilities into an ARV, it is important to target performance that meets or exceeds that of human drivers.This dissertation highlights subsystems within an entire ARV, which are crucial for the completion of a highly functional emergency obstacle avoidance maneuver (EOAM), and combines them in a novel framework while considering the nuances of traveling at highway speeds and/or slippery road surfaces. The primary subsystems developed and tested in this research include the synthesis of ARV sensing, perception, decision making, control, and actuation. These subsystems are introduced with some novelties to the current state-of-the-art as well as the holistic ARV EOAM Framework, designed to handle highway speeds and slippery surfaces, as a novelty. Lastly, a newly considered testing and validation methodology for ARV EOAM performance and validation is presented. This general obstacle avoidance capability assessment (GOACA) has implications for adoption by national or even global regulation bodies, regarding ARV EOAM safety performance while requiring all the core ARV systems to perform well, and in harmony, to achieve top marks

Confidence can be a strong predictor of accuracy if circumstances are ideal (Wixted & Wells, 2017), but ideal circumstances are not always present. As such it is important to understand ways to ameliorate potentially negative effects on eyewitness metacognition. Rapport building, though seen as an important element of police/witness interaction (Vallano et al., 2015), can lead to some potentially negative memory effects (Wright et al., 2015). Additionally steering, or the process of directing a witness toward a particular suspect, can increase false identifications. Recently the researcher has developed a paradigm meant to better calibrate confidence by reinstating the context of making the identification decision. All of these variables were examined with their relation to choosing behavior and self reports of confidence in choosing. Rapport did not significantly affect anything. Steering increased the likelihood of choosing the designated suspect and decreased confidence in decisions. All of the variables interacted providing the most confidence in those who underwent the novel paradigm, had positive rapport, had not been steered, and correctly identified the guilty suspect. The implications of this research both in terms of the greater eyewitness literature and in terms of the effects on the judicial system are discussed.

Abstract: Prostate cancer is one of the most prevalent types of cancers in North American males, afflicting one in eight men over the course of their lifetime. Fortunately, early-stage prostate cancer has a wide variety of treatment options. One such option, permanent prostate brachytherapy, has been proven to have excellent survival rates for low to intermediate risk patients. However, the procedure has a steep learning curve and requires a long training period for new surgeons. Brachytherapy surgeons are also mostly located in urban areas. These factors can significantly limit patient access to procedure. This thesis presents techniques designed to aid surgeons performing permanent prostate brachytherapy. Through the use of 2D ultrasound, we present techniques for needle shape reconstruction, tracking, trajectory prediction, and steering with the goal of improving the quality of information presented to prostate brachytherapy surgeons and helping them to perform the procedure with greater accuracy, consistency, and efficiency.

This thesis describes a precision navigation system for indoor mobile robots, developed to address deficiencies in the ROS navigation stack when used for precision navigation. It includes a precision localization subsystem, based on a planar laser scanner, wheel encoders, a gyroscope and an a priori map, and a precision path execution system made up of a steering algorithm, a trajectory generator and a simplistic path planner. A 3D octree costmap based on the OctoMap library was also developed for collision detection. Geometric parameterizations for path segments were developed for use by those components. The precision navigation system was evaluated using a physical robot, CWRU's HARLIE, as well as in a Gazebo simulation. This precision navigation system allowed HARLIE to precisely navigate indoors, following paths made up of straight lines, constant curvature arcs and spin-in-place segments with as little as just over three centimeters of RMS lateral offset error.

In this thesis an Active Disturbance Rejection Controller (ADRC) is applied to Electrical Power Assist Steering (EPAS) system which assists the driver in steering the steering wheel of an automobile. Our control objective is to reduce the steering torque exerted by a driver, so that good steering feel of the driver will be achieved in the presence of external disturbances and system uncertainties which are very common in the EPAS system. The robustness and stability of ADRC controlled EPAS system is investigated through frequency-domain analyses. The Bode diagrams and stability margins demonstrate that the control system is stable during the operation and it is robust against external disturbances and structural uncertainties. In addition, the ADRC is simulated on a column-type EPAS system. The simulation results show that using the proposed ADRC, the driver can turn the steering wheel with the desired steering torque, which is independent of load torques that tend to vary with the change of driving conditions.

The steering system is a critical component of all ground vehicles regardless of their propulsion source. Chassis directional control is provided by the steering system, which in turn relays valuable feedback about the road and vehicle behavior. As the primary feedback channel to the driver, the steering system also delivers the initial perception of a vehicle's handling and responsiveness to the consumer. Consequently, the steering system is an important aspect of the vehicle's evaluation and purchasing process, even if drivers are unaware of its direct influence in their decision making. With automobile purchases potentially hinging on the steering system, a need exists for a better understanding of steering preference through a focused research project. In this investigation, driver steering preferences have been studied using an advanced hardware-in-the-loop automobile steering simulator. Additionally, vehicle run-off-road situations have been studied, which occur when some of the vehicle wheels drift off the road surface and the driver recovers through steering commands. The Clemson University steering simulator underwent three significant generations of refinements to realize a state-of-the-art automotive engineering tool suitable for human subject testing. The first and third generation refinements focused on creating an immersive environment, while the second generation introduced the accurate reproduction of steering feel found in hydraulic systems and real-time adjustable steering feel. This laboratory simulator was the first known validated driving simulator developed for the sole purpose of supporting driver steering preference studies. The steering simulator successfully passed all validation tests (two pilot studies) leading to an extensive demographics-based driver preference study with 43 subjects. This study reflected the following preliminary trends: Drivers who used their vehicles for utility purposes preferred quicker steering ratios and heavier efforts in residential, country, and highway environments. In contrast, car enthusiasts preferred quick steering ratios in residential and country environments and light steering effort on the highway. Finally, rural drivers preferred quicker steering ratios on country roads. These relationships may be used to set steering targets for future vehicle developments to accurately match vehicles to their intended market segments. The second research aspect was the development of an objective steering metric to evaluate a driver's steering preference. In past simulator studies, driver feedback has been gathered extensively using written questionnaires. However, this delays the testing procedure and introduces an outside influence that may skew results. Through the data collected in this project, a robust objective steering preference metric has been proposed to gather steering preferences without directly communicating with the driver. The weighted steering preference metric demonstrated an excellent correlation with survey responses of -0.39 regardless of steering setting. This global steering preference metric used a combination of yaw rate, longitudinal acceleration, and lateral acceleration. The objective data was further dissected and it was discovered that changes made to the steering ratio resulted in a correlation of -0.55 between the objective data and subjective response from the test subjects. This substantial correlation relied on the longitudinal acceleration, left front tire angle, and throttle position. Beyond steering preferences, vehicle safety remains a major concern for automotive manufacturers. One important type of crash results from the vehicle leaving the road surface and then returning abruptly due to large steering wheel inputs: road runoff and return. A subset of run-off-road crashes that involves a steep hard shoulder has been labeled 'shoulder induced accidents'. An active steering controller was developed to mitigate these 'shoulder induced accidents'. A cornering stiffness estimation technique, using a Kalman filter, was coupled with a full state feedback controller and 'driver intention' module to create a safe solution without excessive intervention. The concept was designed to not only work for shoulder induced accidents, but also for similar road surface fluctuations like patched ice. The vehicle crossed the centerline after 1.0s in the baseline case; the controller was able to improve this to 1.3s for a 30% improvement regardless of driver expertise level. For the case of an attentive driver, the final heading angle of the vehicle was reduced by 47% from 0.48 rad to 0.255 rad. These laboratory investigations have clearly demonstrated that advancements in driver preference and vehicle safety may be realized using simulator technology. The opportunity to apply these tools should result in better vehicles and greater safety of driver and occupants. With the development of the objective steering preference metric, future research opportunities exist. For prior steering preference research, the feedback loop has typically required interaction with the subject to rate a setting before continuing. However, the objective steering preference metric allows this step to be automated, opening the door for the development of an automatic tuning steering system.