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This thesis investigates the principle of co-ordination of chassis subsystems by proposing a new control structure for co-ordinating active steering technologies and a brake based directional stability controller. A non-linear vehicle handling model was developed for this study using the Mattab and Simulink tools. This consists of a 4 degree of freedom (d. o. f) lumped-parameter model that includes longitudinal, lateral, yaw and roll motions with quasi-static longitudinal load transfer effects including non-linear suspension and tyre descriptions. The non-linear vehicle dynamics are discussed for the whole operating regime and two specific driving tasks are identified, steerability and stability. In the context of the vehicle states these are yaw rate control and side slip angle bounding respectively. Linear active steering controllers for front, rear and four wheel steering are designed and evaluated in the context of the vehicle handling problem throughout the non-linear operating regime to assist the driver in the two driving tasks previously defined. It is shown through the analysis of the vehicle dynamics in the Chapter 3 that linear controllers can be used to significantly improve the handling behaviour of a non-linear vehicle when only one active input is considered, however when controlling two active inputs, non-linear multivariable approach is required to deal with the strongly coupled nature of the vehicle handling with respect to front and rear steering inputs. A brake based stability system that reflects the state of the art is implemented. The work then proposes a novel co-ordination controller structure for coordination of an active steering controllers and a brake based stability controller for improving to vehicle handling control. The controller was assessed both in steady state and transient tests selected to simulate real world driving manoeuvres over the whole non-linear vehicle handling regime. The co-ordination controller is found to lead to a trade-off between stability and limit cornering performance. The proposed structure improves vehicle stability and reduces interactions in the longitudinal vehicle motion. A detailed discussion of the implications of a coordinated control approach showing it to be a powerful tool providing, the interactions can be conveniently related vehicle handling task and that an appropriate measure of vehicle performance is available. The limitations of the approach are discussed. The most significant limitations being a) the difficulty in proving the optimalty of a heuristic control structure, b) the difficult in assessing the controller behaviour and its interaction with a real driver and c) the likely complexity of the rule base for coordinating more than 2 or 3 systems or describing more complex interactions than were observed here.

This study examines the Presidential Library System, an agency within the National Archives and Records Administration (NARA), as an example of a policy subsystem. A policy subsystem may be defined as an informal political coalition of individuals from different parts of a formal policy structure who cooperate to influence policy-making. Actors in a policy subsystem are multifarious, they span both public and private sectors at various levels of government, and may include agency personnel, congressional committee members, interest group participants, citizens of localities affected by the subsystem, and others. A policy subsystem's strength lies in its ability to draw upon bureaucratic expertise, legislative leverage, and interest-group capacities to communicate with the government about the area of public policy it is vitally concerned with. Despite the 60 year existence of the Presidential Library System, its nationwide geographic distribution, and its approximately $30 million/year allocation from the federal budget, it is not widely recognized as a policy system and it has not been the subject of a detailed, scholarly description. The Presidential Libraries policy subsystem is described by tracing its development and mapping the richness of the administrative and political processes which support its continuing viability. The specific research questions addressed are:1) how do the administrative and political processes of this policy subsystem unfold, 2) how do these processes provide system maintenance, and 3) who are the players? Qualitative research techniques, via a case study methodology, were used to address these questions.. In-depth interviews were conducted with the directors of the ten Presidential Libraries, the staff of the Office of Presidential Libraries at NARA, and key stakeholders in the system. Questions addressed included: what do all of the presidential libraries share?, what is unique about each?, to what extent IS the Presidential Library System a policy subsystem?, and how is government organized to deal with presidential libraries and their mission of 1) preserving and providing researchers access to presidential papers and historical materials, and 2) providing museums and educational programming designed to give the general public a better understanding of the individual Presidents, the institution of the Presidency, and the American political system as a whole? / Ph. D.

Being hearing impaired does not only affect a child’s academic performance, but can also influence a child’s overall development and ability to succeed academically. Evidence suggests that the outlay in early childhood has a large impact on a child’s readiness to learn. Neurodevelopmental movement programmes are generally not accepted as evidenced-based practice and their effect on academic performance is often underrated. Movement, however, is regarded by many as essential to learning and there seems to be a positive interchange between the brain and the body. This study reports on the influence of a neurodevelopmental movement programme on the development, behaviour and performance on a neurodevelopmental evaluation scale of four to eight year-old children with hearing impairment children. The study furthermore provides a report of the results of the psychometric assessment in the form of a neurodevelopmental profile for this specific sample. Children were selected from a special needs school in the rural QwaQwa Free State area of South Africa. Two groups of children (an experimental and comparison group) were used in this study, with both groups undergoing a pretest and posttest phase using three test batteries (Griffiths Mental Developmental Scales- Extended Revised, Child Behaviour Checklist, and a neurodevelopmental evaluation scale). The experimental group was subjected to a fourteen-week neurodevelopmental movement programme. The comparison group underwent a placebo intervention. The results indicate that the children in the experimental group showed an improvement in some aspects of specific development following the intervention (locomotor functioning, performance related abilities, and practical reasoning skills). General developmental age showed significant improvement in both the experimental group and the comparison group. No behavioural aspects showed significant improvements following the intervention, whereas some neurodevelopmental aspects, such as the vestibular system (Tandem Walk and One Leg Stand) and the reflex system (TLR – reflex) showed significant improvements. The results of this empirical investigation aid in understanding the impact of movement programmes on a child with hearing disability’s general development and neurodevelopmental development. / Thesis (PhD (Psychology))--North-West University, Potchefstroom Campus, 2013.

Being hearing impaired does not only affect a child’s academic performance, but can also influence a child’s overall development and ability to succeed academically. Evidence suggests that the outlay in early childhood has a large impact on a child’s readiness to learn. Neurodevelopmental movement programmes are generally not accepted as evidenced-based practice and their effect on academic performance is often underrated. Movement, however, is regarded by many as essential to learning and there seems to be a positive interchange between the brain and the body. This study reports on the influence of a neurodevelopmental movement programme on the development, behaviour and performance on a neurodevelopmental evaluation scale of four to eight year-old children with hearing impairment children. The study furthermore provides a report of the results of the psychometric assessment in the form of a neurodevelopmental profile for this specific sample. Children were selected from a special needs school in the rural QwaQwa Free State area of South Africa. Two groups of children (an experimental and comparison group) were used in this study, with both groups undergoing a pretest and posttest phase using three test batteries (Griffiths Mental Developmental Scales- Extended Revised, Child Behaviour Checklist, and a neurodevelopmental evaluation scale). The experimental group was subjected to a fourteen-week neurodevelopmental movement programme. The comparison group underwent a placebo intervention. The results indicate that the children in the experimental group showed an improvement in some aspects of specific development following the intervention (locomotor functioning, performance related abilities, and practical reasoning skills). General developmental age showed significant improvement in both the experimental group and the comparison group. No behavioural aspects showed significant improvements following the intervention, whereas some neurodevelopmental aspects, such as the vestibular system (Tandem Walk and One Leg Stand) and the reflex system (TLR – reflex) showed significant improvements. The results of this empirical investigation aid in understanding the impact of movement programmes on a child with hearing disability’s general development and neurodevelopmental development. / Thesis (PhD (Psychology))--North-West University, Potchefstroom Campus, 2013.

The development of a quantum computer presents one of the greatest challenges in science and engineering to date. The promise of more efficient computing based on entangled quantum states and the superposition principle has led to a worldwide explosion of interest in the fields of quantum information and computation. Among the number of hurdles which must first be cleared before we witness a physical realization are problems associated with environment-induced decoherence and noise more generally. However, the discovery of quantum error correction and the establishment of the accuracy threshold theorem provide us with the hope of someday harnessing the potential power a functioning fault-tolerant quantum information processor has to offer. This dissertation contributes to this effort by investigating a particular class of quantum error correcting codes, namely noiseless subsystem encodings. The passive approach to error correction taken by these encodings provides an efficient means of protection from symmetrically coupled system-environment interactions. Here I will present methods for determining the subsystem-preserving evolutions for noiseless subsystem encodings supported by arbitrary-dimensional physical quantum systems. Implications for universal, collective decoherence-free quantum computation using the derived operations are discussed. Moreover, I will present a proposal for an optical device which is capable of preparing a variety of these noiseless subsystem encodings through a postselection strategy.

yes / The set of subsystems ∑ (m) of a finite quantum system ∑(n) (with variables in Ζ(n)) together with logical connectives, is a distributive lattice. With regard to this lattice, the ℓ(m | ρn) = Tr (𝔓(m) ρn ) (where 𝔓(m) is the projector to ∑(m)) obeys a supermodularity inequality, and it is interpreted as a lower probability in the sense of the Dempster–Shafer theory, and not as a Kolmogorov probability. It is shown that the basic concepts of the Dempster–Shafer theory (lower and upper probabilities and the Dempster multivaluedness) are pertinent to the quantum formalism of finite systems.

Small satellites refer to a new breed of smaller and computationally capable satellites, which serve as a ?faster, better, cheaper? means of realizing space missions. To ensure success of a small satellite mission, it is important that systems engineering be applied at the initial stages of the program formalization to provide a basis for defining mission strategies, managing requirements, risk analysis, performing design trades and estimating cost. The objective of this thesis is to formalize a small satellite mission plan while providing recommendations in areas involving design optimization, systems engineering, project management, cost modeling, subsystem design and selection. Finally, this thesis details the preliminary design of a conceptual ?MSUSAT? small satellite, using Commercial Off The Shelf (COTS) components, from a systems engineering perspective. It explains the choice of orbit, payload and other subsystem components that are necessary to ensure that the mission fulfils its objective.

This study provides insights into the behavior of an environmental policy subsystem. The study uses neural network theory to model the Gulf of Mexico Program's allocation of implementation funds. The Gulf of Mexico Program is a prototype effort to institutionalize a policy subsystem. A project implementation fund is at the core of the Gulf of Mexico Program. The United States Environmental Protection Agency provides the implementation fund and the Mexico Program Office (GMPO) administers it. The GMPO uses the implementation fund to encourage other federal, state, local, and private organizations to undertake projects designed to improve the environmental quality and economic vitality of the Gulf of Mexico and its surrounding region. The implementation fund constitutes a program "portfolio" and is the Gulf of Mexico Program's primary means of influencing policy. The way a policy subsystem manages its program portfolio through the allocation of fiscal resources provides important insights about its priority concerns and dominant actors. The benefits of this study are threefold. First, the study offers an initial systematic description and analysis of the Gulf of Mexico Program and its policy implementation process. Second, using the Gulf of Mexico Program as a prototype, the study sheds new light on why and how policy subsystems formulate and implement policy. Finally, the study provides a means to assess the value of neural network theory as a technique for modeling and analyzing policy subsystem behavior. / Ph. D.

Today's product development process should be rapid andcost-efficient, and should result in innovative and reliableproducts. A crucial factor is the dynamic behaviour of theproduct. This thesis focuses on theoretical, numerical andexperimental approaches to achieve a comprehensiveunderstanding of dynamical phenomena occurring in nonlinearproducts, especially in products with parts that includeimpacts. The aim is to show the usefulness of nonlineartheories to better understand and optimise the dynamicbehaviour of products and thereby account for nonlinearphenomena already in the product development process. This is achieved through an investigation of researchefforts in the field of nonlinear dynamics; identification ofimportant research directions; a study on the effect ofcouplings between nonlinear parts; a detailed study on thedynamic behaviour of a product component; investigations oflow-cost strategies for controlling the dynamics of a nonlinearsystem; and the design and implementation of experimentalset-ups of two studied products. The investigation of research efforts shows that nonlinearparts are frequently included in products. Most common areparts that are nonlinear due to impacts and friction. Twoimportant areas are identified; to study coupling effectsbetween nonlinear subsystems and to study how nonlinearanalysis can be used to improve existing designs. Considering the studied products; a pantograph on a trainand a Braille printer, it can be concluded that thecharacteristics of a part can largely affect the dynamicbehaviour of the product. Typical nonlinear behaviour, such ascoexisting solutions and irregular motions, do occur. Theanalysis of the pan- tograph motion shows important aspects toconsider in the modelling process; coupling effects. In thecase of the Braille printer it is shown possible to create alow-cost control, by taking advantage of an existingdiscontinuity, to achieve a desired motion. Altogether, this work contributes to improved understandingof the be- haviour of nonlinear parts in products, especiallythose including impacts, pro- viding greater knowledge aboutaspects to consider in the design process. Keywords:Nonlinear Dynamics, Impacts, Discontinuities,Subsystems, Chaos, Irregular Behaviour, Printer Dynamics,Suspensions, Coupled Systems, Control. / QC 20100621