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This thesis introduces a versatile finite element package, which is tailored for the static and dynamic analysis of radial tyres. A new axisymmetric solid-of-revolution element which takes into consideration, large deformation, the influence of composite orthotropic material and the viscoelasticity and the nonlinearity of the material properties, has been developed for a general loaded tyre. The finite element package has been verified by comparing its results with available analytical, numerical and experimental results. A full static and dynamic investigation has been carried out for a commercial tyre 175 HR 14 and results obtained by using the package have been compared with available experimental results developed by DUNLOP or carried out at Cranfieid. The package has proved to be reliable, flexible, efficient, economic and accurate. The numerical instability problems which are prevalent in this type of analysis have been overcome by the derivation of a developed Newton-Raphson iterative scheme.

Software maintenance is a significant phase of a software life-cycle. Once a system is developed the main focus shifts to maintenance to keep the system up to date. A system may be changed for various reasons such as fulfilling customer requirements, fixing bugs or optimizing existing code. Code needs to be studied and understood before any modification is done to it. Understanding code is a time intensive and often complicated part of software maintenance that is supported by documentation and various tools such as profilers, debuggers and source code analysis techniques. However, most of the tools fail to assist in locating the portions of the code that implement the functionality the software developer is focusing. Mining execution traces can help developers identify parts of the source code specific to the functionality of interest and at the same time help them understand the behaviour of the code. We propose a use-driven hybrid framework of static and dynamic analyses to mine and manage execution traces to support software developers in understanding how the system's functionality is implemented through feature analysis. We express a system's use as a set of tests. In our approach, we develop a set of uses that represents how a system is used or how a user uses some specific functionality. Each use set describes a user's interaction with the system. To manage large and complex traces we organize them by system use and segment them by user interface events. The segmented traces are also clustered based on internal and external method types. The clusters are further categorized into groups based on application programming interfaces and active clones. To further support comprehension we propose a taxonomy of metrics which are used to quantify the trace. To validate the framework we built a tool called TrAM that implements trace mining and provides visualization features. It can quantify the trace method information, mine similar code fragments called active clones, cluster methods based on types, categorise them based on groups and quantify their behavioural aspects using a set of metrics. The tool also lets the users visualize the design and implementation of a system using images, filtering, grouping, event and system use, and present them with values calculated using trace, group, clone and method metrics. We also conducted a case study on five different subject systems using the tool to determine the dynamic properties of the source code clones at runtime and answer three research questions using our findings. We compared our tool with trace mining tools and profilers in terms of features, and scenarios. Finally, we evaluated TrAM by conducting a user study on its effectiveness, usability and information management.

<p> The equilibrium and kinetic properties of semicoherent interfaces between γ precipitates and β matrix in Cu-Zn-Sn are examined using a simple dislocation model. The predicted surface energies and mobilities are compared to those observed in experiments which also assess the validity of current theories of interfacial stability in diffusion-controlled growth.</p> / Thesis / Master of Science (MSc)

<p>As the embedded devices has become more and more generalized and as their product cycles keeps shrinking the field has opened up for the Application Specific Instruction set Processor. A mix between the classic generalized microcontroller and the specialized ASIC the ASIP keeps a set of general processing instructions for executing embedded software but combines that with a set of heavily specialized instructions for speeding up the data intense application core algorithms. One important aspect of the ASIP design flow</p><p>research is cutting design time and cost. One way of that is automation of the instruction set design. In order to do so a process is needed where the algorithm to be ASIPed is analyzed and critical operations are found and exposed so that they can be implemented in special hardware. This process is called profiling. This thesis describes an implementation of a fine grained source code profiler for use in an ASIP design flow. The profiler software is based on a static-dynamic workflow where data is assembled from both static</p><p>analysis and dynamic execution of the program and then analyzed together in an specially made analysis software.</p>

As the embedded devices has become more and more generalized and as their product cycles keeps shrinking the field has opened up for the Application Specific Instruction set Processor. A mix between the classic generalized microcontroller and the specialized ASIC the ASIP keeps a set of general processing instructions for executing embedded software but combines that with a set of heavily specialized instructions for speeding up the data intense application core algorithms. One important aspect of the ASIP design flow research is cutting design time and cost. One way of that is automation of the instruction set design. In order to do so a process is needed where the algorithm to be ASIPed is analyzed and critical operations are found and exposed so that they can be implemented in special hardware. This process is called profiling. This thesis describes an implementation of a fine grained source code profiler for use in an ASIP design flow. The profiler software is based on a static-dynamic workflow where data is assembled from both static analysis and dynamic execution of the program and then analyzed together in an specially made analysis software.

<p> A general formulation of the analysis of plane coupled shear walls is presented. The "continuous method" of analysis of coupled shear walls is reformulated in terms of deflection variables. The assumption that midpoints of the connecting beams are points of contraflexure is relaxed so that the resulting theory is applicable to the general case where the lateral loading on the piers can be arbitrarily distributed. The governing equation of the structural system under static loading with the appropriate boundary conditions are given. The effect of asymmetry of the structure is discussed. As an application of the derived theory, the problem of shear walls subjected to differential foundation settlement and rotation is studied. Solutions to deflections and internal stresses, under such conditions, are given. Evaluation of the internal stresses was performed on a practical shear wall structure and the results analysed. Through the use of deflection variables, the formulation is extended into the regime of dynamics. The governing equation of motion with appropriate boundary conditions are given. The free vibration of coupled shear walls is studied and design curves for the fundamental natural frequency are presented. The use of substitutive symmetric systems and its effects on the fundamental frequency of asymmetric systems are examined. Theoretical natural frequencies were verified by dynamic testing on two models to show that the proposed theory is sufficiently accurate to provide information for dynamic analysis in seismic design. / Thesis / Master of Engineering (ME)

<p> The electron density approach in conjunction with the Hellmann-Feynman theorem is used for a systematic analysis of binding characteristics of the two isoelectronic molecular series: N₂, CO, BF, and LiF, BeO. Electron density distributions, forces and field gradients corresponding to static properties of electron densities, have been calculated from Hartree-Fock wavefunctions (obtained from the work of other authors) for these molecules. Correlation of these static properties with binding characteristics are presented. Covalent and ionic characteristics are made evident by an analysis of the density distributions, density difference maps obtained by subtracting atomic from molecular distributions, and the forces exerted on nuclei by these distributions. A discussion of the field gradients, as related to quadrupole polarizations of the electron densities, is presented and the relevance of these polarizations to the interpretation of nuclear quadrupole coupling constants is indicated. </p> <p> Dynamic properties, as reflected by the magnitude of force constants, are analyzed in terms of functionals of the one-electron density. Force constant expressions are derived from the Hellmann-Feynman theorem. Any relation of force constants to field gradients is shown to be not unique as a result of cancellation of static and dynamic electron contributions to the total force constant. The total electronic contribution is shown to arise from a relaxation of density after a displacement of a certain nucleus. Relaxation of density with respect to one nucleus but which remains localized on some other nucleus in a molecule is shown to be equivalent to a field gradient. Thus, such density is separated from other density and its contribution to the force constant is treated as a field gradient. All contributions are computed from polynomial fits of the corresponding forces calculated at a number of internuclear distances. Relaxation density maps for the remaining atomic and overlap densities centered on a specific nucleus are presented. These maps are calculated as the difference between densities of the extended and equilibrium configurations of a molecule. The relaxation densities are correlated to the magnitude of the corresponding electronic force constant components. Thus, for the first time, there is demonstrated the concrete relation between covalent and ionic characteristics of electron densities in molecules and their dynamic properties which result in the magnitude of force constants. </p> / Thesis / Doctor of Philosophy (PhD)

The contribution of the midfoot in landing mechanics is understudied. Therefore, the main purpose of this study was to quantify midtarsal joint kinematics and kinetics during a barefoot single-leg landing task. A secondary aim of this study was to explore the relationship between static foot posture and dynamic midfoot function. In a cross-sectional study design, 48 females (age = 20.4 ± 1.8 yr, height = 1.6 ± 0.06 m, weight = 57.3 ± 5.5 kg, BMI = 21.6 ± 1.7 kg·m-1) performed drop landings from a height of 0.4 m onto split force platforms. Subjects hung from wooden rings and landed on their dominant leg. Midtarsal joint kinematic and kinetic data were recorded using a motion capture software system in conjunction with a custom multisegment foot model marker set. Arch height index (AHI) for both seated and standing conditions was measured using the Arch Height Index Measurement System (AHIMS). Kinematic data revealed an average sagittal plane midtarsal range of motion (ROM) of 27 degrees through the landing phase. Kinetic data showed that between 7% and 22% of the total power absorption during the landing was performed by the midtarsal joint. Standing AHI was correlated negatively with sagittal plane midtarsal ROM (p = 0.0264) and positively with midtarsal work (p = 0.0212). Standing midfoot angle (MA) was correlated positively with sagittal plane midtarsal ROM (p = 0.0005) and negatively with midtarsal work (p = 0.0250). The midfoot contributes substantially to landing mechanics during a barefoot single-leg landing task. Static foot posture may be a valuable measurement in predicting midfoot kinematics and kinetics.