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Histopathologists typically collect biopsies which leads to image data. They examine the images to obtain various diagnostic summaries, e.g. proportion of tumor. They do this by overlaying a regular grid of points which are then classified. This classification allows them to estimate the proportion of tumor and other statistics. In this thesis, we focus on investigating heterogeneity. We do this by considering measures of clustering in the classified points spatially. We consider the use of cluster statistics in the diagnosis of patient cancer (stomach and rectum cancers). We further consider tests of anisotropy/direction of heterogeneity/clustering. Binary Markov random field parameter estimation is also investigated as an alternative approach for detecting heterogeneity of the image both overall and in a specific direction. Furthermore, we consider spatial prediction and consistency of spot classifications for overlapping regions sampled at different resolutions. In the first part of this thesis, we aim to identify an appropriate spatial autocorrelation statistic measure, under a normal approximation of the statistical test. We investigate the power of Moran's I statistic which has power in the large sample setting. More importantly, the I statistic is then modified to measure the heterogeneity/clustering in different directions. In particular in the cancer studies, associating the cluster direction with that of the lumen surface, which is an important pathological feature, is investigated. Following this, a new simulation-based iterative method for estimating binary Markov random field parameters is explained. Estimated parameters give similar information to the spatial measurements, and this method leads to a statistical test which does not depend on normal approximations. Based on simulation, the accuracy of the iterative method is checked and compared favourably with an existing parameter estimation method. We address the sampling issue by investigating the spatial consistency for pairs of images sampled from the same area but with different resolutions. Finally, we address several clinical questions. For instance, explaining the differences in survival of patients is investigated and it was found that heterogeneity is related to expected survival times.

The thesis investigates the nature of the relationship between the banking sector depth and long-term economic growth in the Gulf Cooperation Council (GCC) States, assesses the banking sector development status in each of the States, and underlines the policy implications in the light of the banking-growth nexus and the banking development benchmarking models’ findings for the region by undertaking three projects. The thesis examines the nature of the relationship between banking sector depth and long-term economic growth in the NRBC—as a proxy for the GCC States— vis-à-vis the rest of the world countries. For the empirical investigation, a dynamic panel data approach, i.e. Generalised Method of Moments (GMM), is adopted over the period 1961 to 2013. By utilising mixed effects and System GMM frameworks, the research identifies the countries with the strongest banking-growth relationships and establishes the banking sector development determinants in those countries. Employing a novel benchmarking process, the thesis assesses the status of the banking sector development in each of the GCC member countries and simulates the change in the banking sector depth across the Gulf region over a period of ten years to highlight the potential policy implications for the sector development. The findings of the thesis suggest that the relationship between banking sector depth and long-term economic growth in the NRBC is non-linear, where the relationship between the banking sector depth and economic growth turns from positive to negative beyond certain levels of sector depth. In comparison to other countries, the results indicate that the banking-growth nexus in the NRBC exhibits a smaller total effect magnitude as well as a shorter time between the change in the sector depth and its effect on economic growth. The benchmarking of the banking sectors in the GCC region suggests that in five of the six member countries the banking sectors are underdeveloped. The simulation results predict that the banking sectors will develop further in half of the countries in the region, given their current levels of banking sector development determinants, while two countries require reforms in terms of undertaking regulations and policies to avoid seeing their sector development levels deteriorate. The thesis contributes to theory by confirming findings in the literature and expanding the body of knowledge through novel findings. This research also contributes to policy by demonstrating the significance of the banking sector development for long-term economic growth in the NRBC, providing policymakers in the Gulf States with the status of their banking sectors, and underlining the banking sector depth determinants that ought to be considered when setting regulations and policies that are aimed at developing the banking sector further.

The aim of the work in this thesis is to carry out dimension reduction (DR) for high dimensional (HD) data by using statistical methods for variable selection, feature extraction and a combination of the two. In Chapter 2, the DR is carried out through robust feature extraction. Robust canonical correlation (RCCA) methods have been proposed. In the correlation matrix of canonical correlation analysis (CCA), we suggest that the Pearson correlation should be substituted by robust correlation measures in order to obtain robust correlation matrices. These matrices have been employed for producing RCCA. Moreover, the classical covariance matrix has been substituted by robust estimators for multivariate location and dispersion in order to get RCCA. In Chapter 3 and 4, the DR is carried out by combining the ideas of variable selection using regularisation methods with feature extraction, through the minimum average variance estimator (MAVE) and single index quantile regression (SIQ) methods, respectively. In particular, we extend the sparse MAVE (SMAVE) reported in (Wang and Yin, 2008) by combining the MAVE loss function with different regularisation penalties in Chapter 3. An extension of the SIQ of Wu et al. (2010) by considering different regularisation penalties is proposed in Chapter 4. In Chapter 5, the DR is done through variable selection under Bayesian framework. A flexible Bayesian framework for regularisation in quantile regression (QR) model has been proposed. This work is different from Bayesian Lasso quantile regression (BLQR), employing the asymmetric Laplace error distribution (ALD). The error distribution is assumed to be an infinite mixture of Gaussian (IMG) densities.

The present study investigates the information gathering behaviour of the academic researchers at Sultan Qaboos University in the Sultanate of Oman. It endeavours to explore researchers' awareness and attitudes towards information sources and services. Research methods for this study were designed from the user-centred perspective with triangulation approach. Hence, data was collected by the use of semistructured interviews as the main instrument with journal study and observation as supplementary tools. The information was collected from the members of the research community in their capacity as users of information. The study investigates the information needs and information gathering habits of the research community and attempts to identify the problems experienced by researchers in accessing and using information. It also seeks to explore the national policy for planning and provision of information. Finally the study examines the performance of the various information services in the context of user needs and the status of the institution library information service provision. The research concludes that present information environment at Sultan Qaboos University is inadequate to meet the information needs of the research community. It was found that the major causes for the situation was the lack of clear information policies, inadequate funding, ineffective partnership between top management and academic researchers, lack of effective in house training and finally absence of a reliable information technology infrastructure.

As a basis for the commercial separation of normal paraffins a detailed study has been made of factors affecting the adsorption of binary liquid mixtures of high molecular weight normal paraffins (C12, C16, and C20) from isooctane on type 5A molecular sieves. The literature relating to molecular sieve properties and applications, and to liquid-phase adsorption of high molecular weight normal paraffin compounds by zeolites, was reviewed. Equilibrium isotherms were determined experimentally for the normal paraffins under investigation at temperatures of 303oK, 323oK and 343oK and showed a non-linear, favourable- type of isotherm. A higher equilibrium amount was adsorbed with lower molecular weight normal paraffins. An increase in adsorption temperature resulted in a decrease in the adsorption value. Kinetics of adsorption were investigated for the three normal paraffins at different temperatures. The effective diffusivity and the rate of adsorption of each normal paraffin increased with an increase in temperature in the range 303 to 343oK. The value of activation energy was between 2 and 4 kcal/mole. The dynamic properties of the three systems were investigated over a range of operating conditions (i.e. temperature, flow rate, feed concentration, and molecular sieve size in the range 0.032 x 10-3 to 2 x 10-3m) with a packed column. The heights of adsorption zones calculated by two independent equations (one based on a constant width, constant velocity and adsorption zone and the second on a solute material balance within the adsorption zone) agreed within 3% which confirmed the validity of using the mass transfer zone concept to provide a simple design procedure for the systems under study. The dynamic capacity of type 5A sieves for n-eicosane was lower than for n-hexadecane and n-dodecane corresponding to a lower equilibrium loading capacity and lower overall mass transfer coefficient. The values of individual external, internal, theoretical and experimental overall mass transfer coefficient were determined. The internal resistance was in all cases rate-controlling. A mathematical model for the prediction of dynamic breakthrough curves was developed analytically and solved from the equilibrium isotherm and the mass transfer rate equation. The experimental breakthrough curves were tested against both the proposed model and a graphical method developed by Treybal. The model produced the best fit with mean relative percent deviations of 26, 22, and 13% for the n-dodecane, n-hexadecane, and n-eicosane systems respectively.

OBJECTIVES: To assess the viability of using high-strength polymers as framework materials for full arch implant-supported fixed prostheses, veneered with full-coverage restorations of different materials. The machinability, mechanical performance, and damping capacity of the polymer-based materials was of interest. METHODS: The two framework polymers – a polyetheretherketone (JUVORA™ Dental Disk, Juvora) (PEEK) and a fiber-reinforced composite (TRINIA™ CAD/CAM Disk, Trinia) (TR) – were characterized with Fourier-Transform Infrared (FTIR) Spectroscopy and energy-dispersive X-ray spectroscopy (EDS). Phase 1 consisted of a machinability study involving the merlon fracture test, which tested the milling success of PEEK and TR at 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, and 0.5 mm. 10 four-walled merlons of each thickness and material were milled out of CAD/CAM Disks (n = 100 merlons, n = 400 walls) using a 5-axis milling machine, inLab MC X5 (Dentsply Sirona, Germany). Milling success rate, fracture height, fracture length, fracture position, fracture direction, and chipping factor were assessed. In phase 2, 20 bars of dimensions 3.3 mm x 10 mm x 40 mm were milled from each of the two framework materials, PEEK and TR, and two veneer materials – a composite resin material (Shofu Disk HC, Shofu, Inc., Kyoto, Japan) (COM), and a high-translucency 3 mol% yttria-stabilized tetragonal zirconia polycrystal material (Cercon® ht, Dentsply Sirona, Bensheim, Germany) (ZR). Framework and veneer bars were bonded to each other in 4 framework/veneer combinations of 10 bilayers each: PEEK/COM (PCB), PEEK/ZR (PZB), TR/COM (TCB), and TR/ZR (TZB). Bilayer bars were loaded to failure in a 3-point bending test. Failure load, biaxial flexural strength, failure pattern and failure mode were documented. In Phase 3, 10 full arch fixed implant-supported frameworks were designed and fabricated in TR material over an epoxy resin model containing 4 implants in the second premolar and lateral incisor positions. 5 frameworks were veneered by COM in the canine to first molar region, while the other 5 were veneered by ZR. Four loading sites were designated per prosthesis in the occlusal surface of the first molars and the first premolars. Prostheses were loaded at the four occlusal sites in 5 cycles of loading and unloading. The damping capacity of the prostheses was calculated based on energy absorbed during loading and unloading. Displacement and permanent deformation values of the prosthesis structures were obtained from the load-displacement data. Prostheses were loaded to failure at the same sites, and failure load and failure mode were observed. RESULTS: The minimum machined thickness of PEEK and TR was 0.5 mm. There was no significant difference between milling success of PEEK and TR, but cumulative success rate was slightly superior in PEEK. PEEK exhibited a ductile response to machining damage, while TR showed a more brittle response. Chipping factor of PEEK was higher than TR eightfold, meaning TR showed an improved marginal integrity at 0.5 mm. Both materials showed concerning signs of machining damage with the milling parameters and tools used in this study. Bilayer bars with a TR framework withstood significantly higher loads at failure compared to bilayers with a PEEK framework. Bilayer bars with a ZR veneer withstood significantly higher loads at failure compared to bilayers with a COM veneer. The biaxial flexural strength of the four framework/veneer combinations could not be compared due to the occurrence of delamination in 3 of the 4 groups. The PZB group was the only group with fracture of both the veneer and framework without any delamination and exhibited a mean biaxial flexural strength of 46.15 ± 5.76 MPa. None of the bilayer bars with a TR framework exhibited framework fracture. In delaminated specimens, bilayer bars with a TR framework exhibited mixed adhesive-cohesive failure on both layers, while bilayer bars with a PEEK framework exhibited purely adhesive failure on the PEEK-cement interface. Full arch implant prostheses with a TR framework demonstrated elastic hysteresis in continuous cycles of cyclic loading, which is evidence of viscoelastic damping. Significantly higher energy absorption was observed in prostheses veneered with COM compared to ZR. Energy absorption decreased with increasing cycles of loading-unloading. Significantly higher maximum displacement was observed in prostheses veneered with COM compared to ZR, and in cantilever support compared to bounded support. Maximum displacement was inversely related to the thickness of the veneer and framework materials. Permanent deformation of the prosthesis was negligible after 10 cycles. The failure pattern of all prostheses presented as fracture in the veneer only and partial delamination of the veneer with mixed adhesive-cohesive failure mode. The mean failure load at ZR-veneered bounded sites was significantly higher than that of COM-veneered bounded sites. The mean failure load at bounded loading sites was significantly higher than that of cantilever loading sites. ZR-veneered prostheses demonstrated failure load values above 1000 N at all sites. CONCLUSION: The merlon fracture test is well-complemented by several quantitative and qualitative measures to assess the machinability of materials. Optimized tools and parameters for milling PEEK and TR should be investigated. Full arch implant prostheses with TR framework and ZR veneer are a viable option for fixed implant rehabilitation demonstrating damping capacity, adequate failure load values, and easy repairability.

Composite has become an important material in various industries. It is used widely in diverse applications such as aerospace, light and heavy industrials. Composite materials are currently a prominent topic in the industrial field, because they are lightweight, become less expensive and easier to manufacture, and have strong mechanical properties. Nondestructive testing (NDT) is one of the modern technologies used for inspection and evaluation of material integrity, it does not damage inspected components, either directly on the surface or deeply in the components. Phased Array Ultrasonic Testing (PAUT) is an advanced NDT technique that depends on multiple elements for detecting defects, with "phase" referring to time and "array" referring to elements. A PAUT system can be set from 16 to 256 elements, and each element can pulse separately. In testing, PAUT data is based on time and amplitude information derived from waveforms. These waveforms and the information extracted from them will commonly be presented in one or more of four formats: A-scans, B-scans, C-scans, or S-scans.

The purpose of this study was to compare the learning styles, as defined by David A. Kolb, of traditional freshmen students and non-traditional freshmen students to determine if there is a significant difference between them. The researcher also collected data to determine if there is a correlation between learning styles for gender and traditional/non-traditional student status. Kolb’s Learning Style Inventory (LSI) was used as the survey instrument and was administered to all students in the sample. The stratified random sample population consisted of 550 students selected from the freshmen class and provided to the researcher by the Office of Institutional Research at the University of Nebraska-Lincoln. One half (275) of the students (traditional) in the population were first-time entering freshmen with a high school graduation year of 2009, under the age of 25, and enrolled full-time (12 or more credit hours). The remaining 275 students (non-traditional) in the sample population were classified as other freshmen and had one of the following characteristics: enrolled part-time (less than 12 credit hours), age 25 or over, or had delayed enrollment by at least one year following high school graduation. The LSI was used to determine the learning styles of the participants.