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This thesis draws on Michel Foucault's late work on the practices of the self to ask whether the ascetic practices and patterns of action suggested by contemporary computer games, which afford players the opportunities to pursue their own self-set goals, further what might be called a 'wandering' away from ourselves, a 'transformation' or 'transfiguration' of what we are. If self-formation is now a terrain on which power and resistance plays out, it is critical to be able to identify pernicious practices that may bind us to the individualising techniques of power, as opposed to transformative ones that enable us to refuse who we are in the move towards freedom. Broaching this question leads to considerations of the implicit ethical foundations presupposed by Foucault's anti-normative ethico-aesthetics, and the limitations of its appeal to a coherence or style seemingly without rules. These considerations have implications for the way in which we understand the practices of self-constitution in computer games. I question whether there is an isomorphism between the way in which power - understood through Foucault's concept of 'governmentality' - works in the present, and the way in which computer games set the conditions under which player practices take place. We are prompted by both to develop a non-coercive relation to a 'truth' through an impetus that originates from us. Computer games are about our identification with processes, which are strengthened by the feedback loops in the game and by the mode of being we elect to adopt as a hexis. Such a structure, however, is insufficiently rigid for computer games to produce discrete subjectivities, and analyses of them must be sensitive as to whether there are any systematic concatenation of player responses. To this end, I suggest a framework, based on Foucault's orthogonal understanding of power-subject, for uncovering the 'rationalities' within games, which are the conditions under which players' practices of the self take place, and which give rise to certain practices of self-constitution over others. It depends on our being able to find or infer player typologies, which are then analysed for their similar patterns of action. This framework is applied to a case study: levelling-up in The Elder Scrolls IV: Oblivion. On the basis of six typologies, a prominent structure of calculative anticipation and deferral emerges, as well as the existence of what is called a super-instrumental approach. In order to disambiguate these findings with respect to their transformative potential, I turn to the transcendental signifiers in Foucault's work and consider the practices of the self as seeking a balance between reason and sense - they are revisited through the lens of Schiller's play drive. This concretises the argument that if the practices of the self are thought capable of moving us towards freedom, we must assume the existence of non-cognitive faculties within us that, when engaged, enable us to be able to distinguish between positive and pernicious self-formation. Given that these judgments cannot be cognitively communicated, we ought to refrain from prescriptivism, yet do have recourse to standards. However, our efforts to cognitively understand this aesthetic interplay between reason and sense are certainly not without importance.

Aerodynamic optimisation plays an increasingly important role in the aircraft industry. In aerodynamic optimisation, shape parameterisation is the key technique, since it determines the design space. The ideal parameterisation method should be able to provide a high level of flexibility with a low number of design variables to reduce the complexity of the design space. In this work, the Class/Shape Function Transformation (CST) method is investigated for geometric representation of an entire transport aircraft for the purpose of aerodynamic optimisation. It is then further developed for an entire passenger transport aircraft, including such components as the wing, horizontal tail plane, vertical tail plane, fuselage, belly fairing, wingtip device, nacelle, flap tracking fairing and pylon. This work presents the parameterisation of these components in detail using the CST methods for the reference of future aerodynamic optimisation work. The intersection line calculation method between CST components is presented for future entire aircraft optimisation. The performance of the CST has been tested as well, and it found a few drawbacks of the CST methods; for example, it cannot provide some key intuitive design parameters and can lose the accuracy in the wing leading edge area. Therefore, two derivatives of the CST method are proposed: one is called the intuitive CST method (iCST), which is to transform the CST parameters to intuitive design parameters; the other is called the RCST method, which is able to increase the fitting accuracy of the original CST method with fewer design variables. Their performances are studied by comparing them regarding their accuracy in inversely fitting a wide range of aerofoils. Finally, the CST method is also developed to represent the shock control bump, which has better curvature continuity than cubic polynomials. The aerodynamic optimisation study based on adjoint approaches is carried out using the above parameterisation methods. Optimisation was performed on two-dimensional cases to make a preliminary investigation of the performances of the above parameterisation methods. The results showed that all of CST, iCST and RCST parameterisation methods are able to successfully reduce the drag. The results of the CST methods showed the lower order CST is able to provide fast convergence, and the high order CST is able to provide more flexibility and more local control of the shape to reach better optimal solution. The iCST providing intuitive parameters is improving the process of setup constraints, which is useful for aerofoil optimisation. The RCST showed good performance in aerodynamic optimisation in terms of convergence rate, number of design variables, low order of polynomials and smoothness of the shape. This work provides a reference to designer for choosing suitable parameterisation method in these three methods regarding specific requirement. The shock control bump optimisation on 2D aerofoil is performed to compare three shock control bump parameterisation methods. The results showed the CST parameterisation method is promising for shock control bump optimisation. Three-dimensional optimisation tests, including wing and winglet drag minimisation, were performed using the above parameterisation methods. The results showed that the CST methods are able to handle three-dimensional wing optimisation. It also investigated the effect of the order of CST method in optimisation. The results showed the lower order CST already performed well in optimisation in terms of optimal results and convergence rate. The optimisation also discussed the importance of using Cmx constraint in aerodynamic optimisation. In the winglet test cases, it showed the CST methods and adjoint approach are able to perform winglet optimisation. The drag of four winglets are successfully reduced. The downward winglet showed the potential benefits in terms of lower wing root bending momentum. At the end, the shock control bump optimisation using CST method on 3D wing has been performed. The results showed the mesh adjoint methods is able to identify the sensitive area for deploying shock control bumps and the CST shock control bump successfully reduced the wave drag.

In this work, the microstructure evolution of Type 316H and Type 321 austenitic stainless steel has been studied by experimental methods and modelling techniques. In the experimental work, the major precipitate evolution in ex-service and laboratory aged Type 316H and Type 321 steels have been identified using multi-characterisation techniques. The precipitation sequences for both materials have been studied within a wide variety of ageing conditions. Due to the very low carbon level in the matrix, it takes far less ageing time (< 100 hours) to form sigma (s) phase in Type 321 comparing to that in Type 316H. The Type 321 sample with low Si concentration did not form G phase. Unusually, a large amount of Martensite (up to 50 vol%) has been observed in the virgin Type 321 submitted to the accelerated ageing programme. The microstructure evolution of delta (d) ferrite at different ageing temperatures for austenitic stainless steel has also been studied. A Monte Carlo model has been developed to predict detailed microstructure evolution during long term ageing. The results of the quantitative precipitate evolution measurements of Type 316H and Type 321 have been used for the calibration of this microstructural evolution model. After proper validation, the microstructural evolution model was in good agreement with the experimental measurements. The effect of precipitation kinetics on the reduction of fracture toughness has been studied by examining the various fracture surfaces with different ageing conditions. A new approach for the long term fracture property prediction in austenitic stainless steels, based on the Monte Carlo microstructural modelling, has been proposed. This fracture prediction uses microstructure modelling predictions of inter-granular precipitation to forecast the life time fracture toughness degradation, which is also in good agreement with previous work. Ultimately, a method for predicting the microstructure, the mechanical properties of these Type 316H and Type 321 austenitic stainless steel and possibly other austenitic stainless steel, over the power plant life time, could be achieved from this work.

Fault Detection and Classification (FDC) is an integral part of Advanced Process Control (APC) in semiconductor manufacturing. The main objective of FDC is to monitor and analyze the variations in the process data to detect anomalies and to identify the potential root causes. With the rapid advancement of sensor and communication technology, a huge amount of data in semiconductor manufacturing is generated. However, designing useful and reliable features from massive process measurements is not an easy task. Moreover, feature extraction must lose some information of the raw data, which might inadvertently eliminate important sensory information and significantly lower the efficiency of model development.This study proposes a novel approach for FDC system in semiconductor manufacturing process. The proposed method can directly process the multivariate raw trace signal data without the feature extraction in order to reduce the efforts in feature designing, by using Time Series Alignment Kernels (TSAKs). The proposed methodology contains two parts: first is the important sensor screening to prioritize the useful sensor channels for FDC model development in semiconductor manufacturing. This method can be used as a pre-processing step prior to modeling, and the selected sensor channels can be leveraged by process engineers for finer modeling. It combines TSAKs with a feature selection algorithm, minimum Redundancy Maximum Relevance (mRMR), to identify the important sensor channels. Furthermore, a TSAK-Kernel Principal Component Analysis (KPCA) algorithm is proposed to visualize the results. Secondly, TSAK-SVM is employed for FDC modeling. Based on TSAKs, the Gram matrix can be generated directly by using the multivariate raw trace signal, which can be plugged into SVM model for modeling. In this study, validation of the proposed method is based on both open-source datasets and the proprietary datasets from a real production line.

Convex cocompact subgroups of rank-one semisimple Lie groups such as PSL(2,R) form a structurally stable class of quasi-isometrically embedded discrete subgroups which are naturally associated to negatively-curved geometric structures. Anosov representations give a higher-rank analogue of convex cocompactness which shares many of its good geometric and dynamical properties, and have become important objects of study in higher Teichmueller theory. In this thesis we introduce relatively dominated representations as a relativization of Anosov representations, or in other words a higher-rank analogue of geometric finiteness---a controlled weakening of convex cocompactness to allow for isolated failures of hyperbolicity. We prove that groups admitting relatively dominated representations must be relatively hyperbolic, that these representations induce limit maps with good properties, provide examples, and draw connections to work of Kapovich--Leeb which also introduces higher-rank analogues of geometric finiteness.

To overcome the issues of mobility degradation and charge trapping in silicon high-κ MOSFET, a stacked Y₂O₃(top)/HfO2(bottom) gate dielectric on silicon substrate has been developed. Compared to the HfO₂ reference, the new dielectric shows similar scalability, but superior channel mobility and device reliability. The mobility improvement can be attributed to reduced remote phonon scattering, which is associated with the smaller ionic polarization of Y₂O₃, and the suppressed coulomb scattering due to less electron trapping in the bulk of high-κ layer, and reduced metal impurities in the substrate. The passivation mechanisms for the silicon IPL passivation technique in GaAs/[alpha]-Si IPL/high-κ MOS system have been investigated. We demonstrate the [alpha]-Si IPL thickness dependence and substrate type dependence of interface state density (Dit) for GaAs MOS capacitors. The interface state density is strongly correlated to the thickness and quality of un-oxidized Si IPL and its interaction with the underlying substrate. The results can be explained by the models related to the quantum well narrowing or the reduced local trap density as the unoxidized Si IPL layer thickness decreases. By using optimal Si IPL thickness (~10 Å), GaAs MOS devices can achieve the same interface quality, as its silicon counterpart. Using Si IPL to unpin the surface Fermi level, the selfaligned depletion-mode and enhancement-mode GaAs n-MOSFETs are demonstrated. In addition, the charge trapping and wear-out characteristics of the GaAs/Si IPL/HfO2/TaN MOS devices are systematically investigated. High performance In0.53Ga0.47As nMOSFETs with Si IPL and HfO2 gate oxide have been demonstrated. We systematically investigate the impacts of 1) Source/Drain activation temperature, 2) post deposition annealing (PDA) temperature, 3) In[subscrip 0.53]Ga[subscript 0.47]As channel doping concentration, 4) channel thickness and 5) Si IPL thickness on the transistor performances. With the [mu]m, V[subscript d]=50 mV), drive current of 158 mA/mm (L[subscript g]=5 [mu]m, V[subscript gs]=V[subscript th]+2 V, V[subscript d]=2.5 V), and the peak effective channel mobility of 1034 cm2/V-s. InP nMOSFETs with Si IPL and HfO₂ have been demonstrated. The effects of Si IPL on the transistor performances and reliability characteristics are investigated. It is found that even through InP is a forgiving channel material with respect to surface Fermi level pinning, applying silicon IPL still improves the transistor performance and reliability. But the choice of Si IPL is critical for device design. Both in-sufficient passivation and excessive Si IPL should be avoided. optimal combination of these impacting factors, excellent device characteristics have been obtained, including the peak transconductance of 7.7 mS/mm (Lg=5 μm, Vd=50 mV), drive current of 158 mA/mm (Lg=5 [mu]m, Vgs=Vth+2 V, Vd=2.5 V), and the peak effective channel mobility of 1034 cm2/V-s. InP nMOSFETs with Si IPL and HfO₂ have been demonstrated. The effects of Si IPL on the transistor performances and reliability characteristics are investigated. It is found that even through InP is a forgiving channel material with respect to surface Fermi level pinning, applying silicon IPL still improves the transistor performance and reliability. But the choice of Si IPL is critical for device design. Both in-sufficient passivation and excessive Si IPL should be avoided.

The pavement distresses including stripping, rutting, and low temperature cracking have been known to greatly decrease the service life of pavement. The simple laboratory tests are used to measure HMA's (Hot Mix Asphalt) fundamental engineering properties that can be linked back to the pavement distress-prediction models. It is envisioned that these simple laboratory tests would play a key role in the quality control of HMA mixtures. To minimize premature pavement distresses, it is imperative to investigate the relationship between the simple laboratory tests and pavement distresses.Moisture induced damage in asphalt concrete pavement, better known as stripping, is a primary cause of distresses in the Hot Mix Asphalt layer. AASHTO T 283 has historically been used to detect moisture damage of asphalt mixes. This method is established for the Marshall mix design process. However, the current hot mix asphalt design calls for the use of Superpave mix design procedure using the Superpave Gyratory Compactor. The differences in the mix design methods will most likely introduce significant differences in stripping test results. Therefore, there is a need to improve the AASHTO T 283 test procedure and to develop the new criterion for the Superpave HMA specimens. A structured laboratory program test is conducted in this research to study the effects of the various factors on the HMA specimen's susceptibility to moisture damage. The experimental test program is divided into two parts: one part is a complete factorial experimental program for two aggregate sources with virgin asphalt binder, the second part is a partial factorial experimental program for the other two aggregate sources with polymer modified asphalt binders. The complete factorial experiment is used to identify and evaluate the contributions of the individual factors, along with all the possible interactions among the various factors. The partial factorial experiment, on the other hand, is used for validating findings from complete factorial experimental results. In the data analysis, the effects of different factors on dry tensile strength, freeze-thaw conditioned tensile strength, and tensile strength ratio (TSR) are investigated in this research. The effects of all the factors investigated in this research are summarized in this research. The recommendations for the proposed stripping test procedure for Superpave HMA are given finally.Rutting and low temperature cracking are also primary failure modes of Hot Mix Asphalt pavements. In the mid-1980s, polymer-modified asphalt concrete mixture has been widely used to minimize rutting and low temperature cracking failures of flexible pavement. In this research, three polymer modifiers are used in the laboratory test. The influences of the modifiers to rutting resistance and low temperature cracking resistance are investigated and regression procedures are performed in an attempt to develop mathematical relationships between pavement distresses properties and HMA's physical properties and strength properties obtained from the simple laboratory tests.