No description available.

Poly(methyl methacrylate) (PMMA) and polystyrene (PS), which are fully amorphous polymers, have been extensively studied for over a decade to discover how their mechanical behaviours vary with temperatures and strain rates. In this study, Mechanical tests were carried out at a range of strain rates and temperatures using a Hounsfield H50KM Test Machine wluch provides quasi- static rates (10-4 - 10-3 S-l) and low strain rates (10-2 - 10-1 S-l), and an in-house built Dropweight Machine which provides high strain rates (102 - 103 S-l) Mechanical tests were also performed in a high-speed photographic system, which provides high strain rates (103 S-l), to visualise the deformation of the polymers at a range of temperatures. An aluminium-heating block was built to heat up the samples to the required temperature. Strain limited tests were carried out at a range of strain rates and temperatures. Differential Scanning Calorimetry (DSC) was employed to study the glass transition temperatures and the specific heats of the samples. Dynamic Mechanical Thermal Analysis (DMTA) was adopted to study the transitions in the samples and the change of moduli with temperature densities of samples before and after high strain rate compression at certain strain were measured using a Six Column Density Apparatus The polarising microscope was used to study the orientation of the polymer chains at a range of temperatures, strains and strain rates. Eyring's theory of viscous flow was applied on yield point, 20% and 30% strain to relate the activation energy and volume with strain rate and temperature from the thermodynamic perspective. Temperature rise was calculated for high strain rate data to fit into the isothermal curve for the application of Eyring's theory and to obtain the actual smnple temperature at which the deformation took place. PMMA and PS showed ductile behaviour when tested at quasi-static and low strain rates at temperatures below their ductile-brittle transition temperatures. The densities of samples were not found to increase at different strains. The orientations of polymer chains did not influence the increase at Yield stress at high strain rates. The interpretation of activation energy and volume provided information of how the flows of chains took place at different temperatures and strain rates.

No description available.

No description available.

Should we be concerned about the more than 30 percent national dropout rate? Can anything be done to intervene successfully? Many students who drop out of school have the intellectual ability to complete college (Howard and Anderson, 1978). If this is so, then our educational institutions are failing them and doing them a tremendous disservice (Committee of Canadian Council for Exceptional Children, 1992). / This research investigates the high school dropout phenomenon in Quebec through the "eyes" of potential dropouts. The project examines the high school dropout phenomenon from the perspective of students who are at risk of leaving school prematurely. The objectives of the research are to investigate how potential high school dropouts perceive success, and to find out what program reforms these students believe are necessary to keep them in school. In the data analysis the students' schooling experiences are critically examined, and factors such as students' perception of public high schools, social affairs schools, teachers and their view of success are considered. These considerations are made within the conceptual framework of a variety of sociological theories in education. Social Affairs schools are special schools reserved for youths who are wards of the court, and those who are in the care of Youth Protection because they cannot live at home. / This study provides richly descriptive narrative accounts of the students' experiences, thoughts and feelings. The study gives voice to high school students who are at risk of dropping out, and of their views of what their needs are to be successful in school. Data collected from this study can be used to develop suitable programs for students. The study concludes by signaling a call to parents, teachers, governments, policy-makers, and caregivers to listen to children and to involve them in matters that are important to them---such as their views of how they can achieve school success.

ChipMulti-processor (CMP) architectures have become mainstream for designing processors. With a large number of cores, Network-On-Chip (NOC) provides a scalable communication method for CMPs. NOC must be carefully designed to provide low latencies and high throughput in the resource-constrained environment. To improve the network throughput, we propose the Very Long Packet Window (VLPW) architecture for the NOC router design that tries to close the throughput gap between state-of-the-art on-chip routers and the ideal interconnect fabric. To improve throughput, VLPW optimizes Switch Allocation (SA) efficiency. Existing SA normally applies Round-Robin scheduling to arbitrate among the packets targeting the same output port. However, this simple approach suffers from low arbitration efficiency and incurs low network throughput. Instead of relying solely on simple switch scheduling, the VLPW router design globally schedules all the input packets, resolves the output conflicts and achieves high throughput. With the VLPW architecture, we propose two scheduling schemes: Global Fairness and Global Diversity. Our simulation results show that the VLPW router achieves more than 20% throughput improvement without negative effects on zero-load latency.

Thesis (M Project Management)--University of South Australia, 1997

Thesis (MEng in Electrical Engineering)--University of South Australia, 1996

Integrated gasification combined cycle is an advanced electricity generation technology, based on coal gasification. Wider deployment requires further research into the components of the process, including coal gasification. The coal gasification reactions are the slowest step in the gasifier and therefore determine size and operating conditions. Understanding the rate of the gasification reactions at high temperatures is crucial for accurate design and optimisation of the gasification process. While the rates have been measured at low temperature, limited data exist at the high temperatures and pressures relevant to entrained flow gasifiers. As the reactions are solid gas reactions, at high temperature they depend on both reaction rate and gas diffusion rate, which complicates the extrapolation of low temperature data. High temperature data measured thus far is only applicable to certain coals, as the gasification rates were not related to char properties. The aim of this thesis was to measure the high temperature gasification rates of three coal char samples and interpret the results in terms of the char morphology and intrinsic reactivity. The results showed that the gasification rate depended on both intrinsic reaction rate and diffusion rate under the experimental conditions. The majority of the char particles were very swollen, with high porosity and thin walls, whereas the conventional analysis approach assumes porous spherical particles. The effectiveness factor approach was modified to incorporate flat-plate geometry, and used to extract the intrinsic reaction rate from the gasification rate data, which showed that the intrinsic reaction rate could be extrapolated to higher temperatures. The application of the effectiveness factor for estimating the gasification rate was demonstrated, and the modified approach was found to give a better estimation of char gasification rate at high temperature. Accurate measurement of char wall thickness and porosity was identified for potential improvement of the approach. Char conversion in a pilot-scale entrained flow gasifier was then explained in terms of char reaction rate, char morphology and reaction temperature, which showed the need for the development of more accurate models of char conversion in gasifiers, to which the work in this thesis can be applied.

Includes bibliographical references (leaves [138]-186) / xiii, 186 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Describes the kinetics of the hepatic lipase mediated hydrolysis of phospholipids and triacylglycerol in spherical, apolipoprotein-specific reconstituted high density lipoproteins. The results show that apolipoproteins have a major impact on these processes. / Thesis (Ph.D.)--Adelaide University, Dept. of Medicine, 2001