Digitized University of Waterloo Theses

Permanent URI for this collectionhttps://hdl.handle.net/10012/21195

The following collection includes theses created by UW graduate students prior to 2010 that have since been digitized. Please note that not all theses written by UW graduate students have been digitized. Current graduate students should only submit their work in the Theses collection.

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Directional dependence of phase transition splitting by uniaxial strain: A new test to determine strontium ruthenate superconducting states
(University of Waterloo, 2014-06) Chen, Anffany
Since the discovery of superconductivity in strontium ruthenate, there has been a widespread effort to understand its properties on a phenomenological level. To this date, there is not enough coherent experimental evidence to conclude if the superconducting phase has broken time-reversal symmetry. In this article we propose a new test based on the fact that for a multi-component order parameter, the application of uniaxial stress could cause phase transition splitting. Our analysis shows that such splitting depends on the direction of applied stress, and such directional dependence is different for every predicted superconducting phase. In particular, splitting occurs at all directions if and only if the superconducting phase is the one with broken time-reversal symmetry.
Uniqueness constraints in object-relational databases and description logics
(University of Waterloo, 2000) Khizder, Vitaliy Leonidovich
Modeling the thermal performance of windows using a two-dimensional finite volume model
(University of Waterloo, 1997) De Abreu, Pedro Felipe
The objective of this research is the numerical determination of overall heat transfer coefficients (U-Factor), solar heat gain factors (SHGF), and surface temperature profiles of windows. The program used takes account of the presence of the natural convection, the radiation between panes, and the thermal effects of the frame. Temperature profiles are useful for the calculation of thermal stresses in glazings and the prediction of condensation problems. Results are compared with measurements and the numerical calculation of others. In benchmark solution comparisons errors, are less than 10^-2%. Comparisons with the numerically determined heat flux through a cavity bounded by two sheets of glass and spacer bars, i.e., a simple window, differed by less than 1%. In a comparison between simulated solar heat gain factors and solar calorimeter experimental results very good agreement is obtained for nine samples, with errors of 2.5% or less for seven samples, and errors of 12% and 5% for the other two. From the simulation of more realistic windows, both geometrically and with respect to boundary conditions this work yielded the following observations: In modeling an entire wood frame window the error in U-factor is 0.38% while the maximum surface temperature difference is less than 0.5%; A quantitative comparison with a set of thermographic measurements for a flush mounted insulated glazing unit (IGU) yielded satisfactory results for clear double glazed units with the center glass temperature differing by about 1oC, and very good agreement for the triple glazed units and the double low-E unit with the center glass temperature differing by less than 0.25oC; And, the effects of heat transfer coefficients in flush and recessed mounted IGU's clearly reveal the importance of modeling a locally varying heat transfer coefficient.
The integrated space-time finite volume method
(University of Waterloo, 1999) Zwart, Philip J.
The integrated space-time finite volume method for predicting time-dependent fluid flow problems is developed. By enforcing discrete conservation over space-time control volumes hich fill the space-time domain, this method satisfies global conservation in space-time. Unlike traditional finite volume methods, there is no need to incorporate the Leibnitz Rule or the geometrical conservation law into the discretization. The method is validated using a variety of two-dimensional problems featuring both prescribed and free boundary motion. Advances in other aspects of cell-centered finite volume discretization - most notably in the modelling of diffusion terms and free surface flows - are also described.
Entrepreneurship and the intersection of work, leisure, and family
(University of Waterloo, 2000) Rehman, Laurene A.
Entrepreneurship, and more specifically, home-based operations are frequently cited as a new and progressive form of employment that will not only lead to enhanced economic development, but will also improve the quality of life for people employed in this market sector. Some of the main advantages believed to be associated with entrepreneurship include greater flexibility and autonomy in relation to work schedule, greater independence, and increased opportunities for career advancement. Yet, at the same time, the entrepreneur may face challenges obtaining sufficient start-up capital, obtaining financing for expansion of current operations, and developing relationships with clients. Many of these concerns may be exacerbated for women due to traditional gendered ideologies and stereotypes. For example, women continue to retain primary responsibility for childcare and may, therefore, face challenges negotiating family commitments in addition to paid employment. The purpose of this study was to critically examine the experience of entrepreneurship for women and men in home-based businesses, and in particular to explore how these entrepreneurs manage and negotiate the competing life spheres of work, family, and leisure. The study examined the values assigned to work, family and leisure, the extent to which conflicts were experienced between life spheres, and whether the entrepreneurs were able to achieve a sense of balance in their lives. Particular attention was paid to the role of gender and gender relations in determining the daily life experiences of the entrepreneurs. A feminist qualitative methodology was utilized to gather data from 13 entrepreneurs (7 men and 6 women) who owned home-based businesses located in St. John's and Mount Pearl, Newfoundland and Labrador. Nine of the businesses were sole-proprietorships and two were partnerships (owned and operated jointly by both spouses), as well, all of the businesses had been in operation for at least two years. The majority of the entrepreneurs were married (n=11) and six single (with one living with an opposite sex partner and the other recently divorced). In-depth interviews were conducted with the entrepreneurs and with five of their life partners. The interviews focused on the daily life experiences of the entrepreneurs, including the time spent on work, family and leisure, as well as the kinds of activities involved, and the experiences and valuations of each life sphere. In addition, reasons for moving into entrepreneurial work were explored. The life partners were asked about their experiences of living with an entrepreneur and about family and leisure activities. The data were analyzed qualitatively, using the constant comparison method, and the Q.S.R. *N.U.D.ist. software programme to search for emergent themes. Validation interviews were conducted, both with the entrepreneurs and with the life partners, to tests these emergent themes. The analysis showed that gender was a primary determinant of the daily life experiences of these entrepreneurs. The men devoted more time to their businesses and were away from home on business-related matters more frequently than the women. As a result the men spent considerably less time than the women in household or family activities, although most of the men did engage in leisure activities outside the home with friends or colleagues. The women's lives represented a combination of paid work and household work. In all of the cases, except one, they retained primary responsibility for the home and family, despite being in two-income households. Participation in leisure activities for the women also sustained this focus upon the family as their involvement centered upon their children, with very few opportunities being experienced for personal leisure. When reflecting upon their negotiations of work, leisure, and family, differential experiences were uncovered for the women and men. The women were more satisfied with their ability to balance work and family, while the men expressed frustration at not being able to spend more time at home. Most of the women had chosen entrepreneurial work so that they could spend time with their children, while the men had more typically been pushed into this form of employment for economic reasons. The findings indicate the centrality of gender in the lives of entrepreneurs. This was evident in their work-related decisions, their division of household labour within the family, and their leisure constraints and opportunities. In addition, the entrepreneurs' negotiations of their daily lives can also be seen as reproducing gender, in that the gendered basis for their decisions reinforced traditional ideologies associated with femininity, masculinity, motherhood and fatherhood. While the women indicated some freedom of choice with regard to their work, this was clearly constrained by their family responsibilities. The men, on the other hand, felt they had less freedom regarding their decision to operate a business, but more freedom in relation to their family and leisure spheres. The Newfoundland culture, which places particular importance on family and family life, also played a significant role in the experiences of the entrepreneurs in this study. This focus upon family produced a sense of pride and satisfaction for the women with their key role in the family unit, but a sense of loss for the men who played a much smaller role in the family. Overall, it was evident that entrepreneurial work does not provide easy solutions to quality of life concerns for employed people. While this form of employment does have some advantages (e.g., greater ability to combine work and family for women, a larger potential income), it also has many disadvantages (e.g., leisure constraints, lack of freedom), and continues to reinforce traditional ideologies of gender.
Leisure and spiritual well-being, a social scientific exploration
(University of Waterloo, 1999) Heintzman, Paul Alexander.
Fish-benthos correlations and effects on benthos that reflect significant effects on fish communities in southern Ontario streams
(University of Waterloo, 1997) Kilgour, Bruce William
This thesis attempts to determine the types of effects on benthic community composition that can be considered to have ecological consequence. The approach was based on the philosophy that changes in benthos are of little significant unless they coincide with unacceptable changes in fishery resources The derivation of critical benthic community effect sizes required four components. First, a definition of unacceptable change in a fishery resource. Second, selection of some aspect of fishery resources that could be considered important to prevent damage to. Third, a demonstration that benthic community composition was inherently related to relevant descriptors of the condition of a fishery. And finally, specific relationships between benthic community composition and the fishery descriptor, from which critical benthic effect sizes could be determined. To define an unacceptable change in a fishery resource, I adopted the use of normal ranges which are inherent in most goal-setting forums. Historically, two problems with the use of normal ranges has been in the application of normal ranges to multivariate descriptors, and in the application of appropriate statistical tests for comparing "impact" locations against the normal range. I therefore provide an operational definition for the normal range that simplifies the use of normal ranges in hypothesis testing. I also demonstrate three statistical tests that can be used to determine when a point observation falls outside of the normal range. The consequences of using conventional two-sample contrasts in relation to one-sample non-central equivalence and interval tests are determined. For sites that are truly outside of the normal range of variation for reference locations, equivalence tests will lead to erroneous conclusions of no impact at most 5% of the time. Two-sample contrasts will lead to erroneous conclusions of no impact about 50% of the time with low sample sizes (i.e., 10-20 reference locations). In contrast to both the two-sample contrast and the equivalence test, interval tests fail to recognize sites as being impacted unless impacts are in excess of about 3 o from the reference population average (with a reference sample size of 20). Finally, the penalty for using the equivalence test is that it will fail up to 26% of sites that are truly members of the reference population. Practitioners contrasting non-random impacted locations against a set of reference locations should consider these characteristics of the various potential tests when deriving conclusions of impact. Fish community data from 37 streams, variously affected by agriculture, urbanization and impoundments, were used to determine the statistical power of various descriptors of fish community composition. In general, single-pass estimates of biomass of all species, and using a multivariate approach to describing the community, provided more modelling and statistical power. In contrast, measuring only the abundances or biomasses of individual (preferred) species like brook trout, was a less powerful method (statistically) for characterizing the fishery of a stream, and was less useful for modelling purposes. To demonstrate consistent associations between fish and benthos, I used three independent data sets in which fish and benthos were collected across stream size and temperature gradients. These data showed consistent and strong associations between stream fish and benthos community composition. The data also suggested that more detailed benthic taxonomy resulted in stronger associations between fish and benthos, and provided evidence that the fish-benthos association is strongly driven by coincident association of fish and benthos with environmental conditions. Finally, critical benthic effect sizes were determined for 11 combinations of data sets to explore sources of variation in derived critical values. In general, benthic critical values that coincided with ecologically relevant effects on fish were less than the normal range of variation for benthic communities, but varied with factors such as the type of benthic sampling apparatus, the microhabitat benthos were collected from, and the nature of the study design (i.e., whether it incorporated regional-reference or site-specific reference locations). Although the fish-benthos correlations were significant regardless of the level of benthic identification, identifying benthos to species resulted in more accurate prediction of the condition of fish communities. In addition, the reliability of benthos was higher when the reference fish community was a brook trout community, or when the assessment was site specific. In both situations, changes in fish communities from reference to impacted conditions were abrupt. The results from this study have obvious application to aquatic environmental assessments, particularly stream assessments in southern Ontario. Benthic criteria, such as those derived here, should be applied in association with relevant statistical procedures, primarily non-central interval or equivalence tests. These tests will provide exact probabilities that benthic community composition in impacted locations exceeds the benthic critical value.
Preparation and synthetic applications of Ã-alkoxystannanes as precursors to Ã-alkoxyorganolithiums
(University of Waterloo, 2001) Nielsen, Nathan Hans
Plastic collapse of circumferential surface defects in pipeline materials
(University of Waterloo, 1997) Choi, Jae-Boong
Pairwise balanced designs and related codes
(University of Waterloo, 1997) Ling, Chi H. A.
This thesis deals with pairwise balanced designs, group divisible designs and related codes. We study pairwise balanced designs with three consecutive block sizes. In particular, we investigate the spectrum of pairwise balanced designs with block sizes give, six and seven; six, seven and eight; seven, eight and nine; and eight, nine and ten. We have standardized the known techniques for constructing pairwise balanced designs with consecutive block sizes. New constructions employing certain line configurations in finite projective planes are also developed. The direct and recursive constructions both require the existence of finite projective planes, particularly goals in desarguesian projective planes. Combining known and new techniques, we have essentially determined the spectra for these pairwise balanced designs. We also study uniform group divisible designs with block size five. We prove that uniform group divisible designs with block size five exists for all parameters satisfying the basic necessary conditions with a finite number of possible exceptions. Many of direct constructions are required to obtain this strong existence result. In particular, we have constructed many group divisible designs with block five admitting a large automorphism group. Several new recursive constructions are presented and used to settle this problem. One recursive construction requires a relatively new type of combinatorial design, the modified group divisible design, which is also studied in this thesis. Finally, we study some coding theoretic problems arising from computer science which have design theoretic connections. We have related a well known problem in combinatorial design theory and finite geometry to coding theory. The existence of anti-Pasch Steiner triple systems corresponds to the existence of a certain type of erasure code. We generalize the existing constructions to obtain some new infinite classes of anti-Pasch Steiner triple systems. In addition, we study some related problems concerning Steiner triple systems avoiding certain configurations.
A comparison of 2D and 3D interfaces for editing surfaces reconstructed from contours
(University of Waterloo, 1997) Waterhouse, Julie Frances
The last decade of computer technology has seen the proliferation of computer graphics applications. As technology advances, there is a growing fascination with three-dimensional (3D) object representations that likely comes from their greater ability to match "real life" than their two-dimensional (2D) counterparts. Unfortunately, the benefits of 3D editing are not without a price. Most techniques for manipulating objects in a 3D environment are developed for conventional hardware configurations that use 2D input devices and CRT displays. The difficulties lie in mapping 3D spatial relationships to 2D displays, an in mapping 2D user input to 3D object manipulation. This mapping problem is somewhat mitigated by adding constraints to the degrees of freedom in the manipulation task. 3D surfaces that have been reconstructed from contours are interesting to consider as targets of 3D interaction because they provide an inherent constraint on manipulation: point motion is restricted to a plane. As part of my research, I implemented an interactive contour editor to edit 3D surfaces that were reconstructed from planar contours. More precisely, the editor is a tool for visualising a surface derived from a set of serial sections, and for removing deformations from this surface. It was designed specifically to remove artefacts from medical images of arteries. I used the interface from my editor in an experiment that tested whether users were faster and more accurate at manipulating surfaces in a 2D environment or a 3D environment. At the outset of this study, I predicted that 2D would be better for editing deformations of a 2D nature. That prediction was borne out by my experimental results. I had also hoped that 3D would be superior as an editing environment for correcting deformations of a 3D nature. However, the 2D character of the data had a stronger effect on performance than did the 3D character of the deformation. Despite the inherent constraints in their surfaces, participants were faster at editing in 2D for all types of deformations, while maintaining a consistent accuracy between 2D and 3D. Participants did perceive a 3D environment to be better than a 2D environment for manipulating a group of points that spanned multiple contours, although this was not reflected in the quantitative results. The intuitive preference for 3D in this situation leads me to believe that it is worth continuing the search for a natural and effective interface for editing surfaces in a 3D environment.
Image sensor pixel integration for large area imaging
(University of Waterloo, 2001) Park, Byung-kyu
This thesis examines the various issues underlying integration of Mo/a-Si:H image sensor with inverted-staggered thin film transistor (TFT)for large area digital x-ray imaging applications. The thin film transistor process has been modified to include a highly doped (n^) microcrystalline silicon (uc-Si:H) film as the contact layer in the sorce and drain regions. The deposition temperature of the n^+ film as the contact layer in the source and drain regions. The deposition temperature of the n^+ uc-Si:H film is varied from 200*C to 400*C to observe the crystalline and amorphous phase formations in these films. The results show that the films deposited at low temperatures are more crystalline in nature than their high temperature counterparts. A comparison of the performance of aluminum (Al)-gated thin film transistors is presented in which the process parameters are varied in terms of the sputter deposition temperature, process pressure, and power. Gate films deposited at 30*C/5mTorr/300W yield TFT characteristics with low leakage current (~10 fA at low Vps), an ON/OFF ratio better than 10^8, and a mobility of 1.1 cm^2/Vs. In contrast, films deposited at 150*C/10mTorr/400W, yield a significant degradation in leakage current (~ 1 pA) and mobility (0.77 cm^2/Vs). The degradation stems from the high surface roughness of the a-SiN:H gate insulator, and hence the TFT channel. Two different pixel integration processes for direct x-ray detection are studied. In one process, the Schottky diode is stacked on top of the TFT. In the other process, the two devices did not overlap. The two processes are compared in terms of mask count and pixel performance. Fully-overlapped and partially-overlapped pixel structures provide high fill factor, but suffer from the stresses due to multi-layers. In addition, the TFT leakage current of a fully-overlapped pixel is very high (~10^-7 A), due to parasitic capacitance. The partially-overlapped structure also suffers from high stress, however, the leakage current is considerably lower and comparable to that of a discrete TFT. The stress is not as severe in the non-overlapping structures. Also, the leakage current is of the order of 100fA. The high intrinsic film stress associated with the stacked pixel structures has been further investigated. It is shown that the high compressive stress of Mo film (~10^9 Pa) can be reduced to ~10^7 Pa by varying the deposition process parameters without seriously undermining the physical and electrical properties of the films. A small-scale (4 rows x 5 columns) teat array has been designed and characterized. The results show that several technical challenges need to first be solved before extending the design to a larger array for x-ray image generation. The most outstanding challenge is to improve the uniformity of the Schottky diode interface.
The spectrum of lipid particles in Phaseolus vulgaris seeds
(University of Waterloo, 1999) Froese, Carol D.
Discretionary capitalisation of R&D expenditures in Canada and Australia
(University of Waterloo, 1999) Smith, Dean Travis
Development and modelling of a new catalytic distillation process
(University of Waterloo, 1997) Podrebarac, Gary
Catalytic Distillation (CD) is a relatively new process used by the petrochemical industry. The process involves placing a heterogeneous catalyst inside of a distillation column so that a chemical reaction and product separation can take place simultaneously in the same piece of equipment. The first commercial application of CD was introduced in 1980 for the production of methyl tertiary-butyl ether (MTBE), and the success of this process has created a great deal of interest in using CD as a more generally applied reaction technique. This thesis describes a new application of CD for the production of diacetone alcohol (DAA) via the base-catalyzed aldol condensation of acetone. This reaction is equilibrium limited to only 4.3 wt% conversion of acetone to DAA at 54*C. As well, DAA can dehydrate to mesityl oxide (MO). MO can continue to react with acetone to form heavier byproducts. DAA is a very useful chemical intermediate and an environmentally friendly cleaning solvent. Therefore, this reaction is commercially relevant, while providing an opportunity to study product selectivity and verify that CD can increase the conversion of acetone beyond the equilibrium limit. An important goal of this thesis is to develop a new model of CD that takes into account mass transfer between the catalyst and the liquid phase. It is well known that mass transfer can influence the reaction rate and product selectivity of a heterogeneously catalyzed reaction. Yet, as the literature currently exists, no models of CD take mass transfer into account. In order to develop a model of CD, an experimental program was completed to obtain basic data for reaction kinetics and mass transfer. The rate of DAA formation over the anion exchange resin catalyst was found to be strongly limited by pore diffusion, having an estimated Thiele modulus of 11. However, reaction rates in the batch reactor were not influenced by external mass transfer to the catalyst surface. The reaction rate was also found to be extremely sensitive to the background concentration of water in the reaction mixture. Although high water concentrations slow down the rate of DAA formation, they improve the selectivity of the reaction toward DAA and improve the lifetime of the catalyst. Mass transfer experiments were also conducted. Mass transfer rates between the catalyst structure and the liquid flowing through the column and mass transfer coefficients for rate-based distillation were measured. The rate of mass transfer between the liquid and the catalyst, however, was found to be extremely sensitive to the flow pattern which is established in the column. This created certain difficulties since flow patterns in packed distillation columns establish themselves in a random way. Thus, it is impossible to make the model of CD completely predictive. Certain steps may be taken, however, such as using liquid distributors, to improve the reproducibility and the predictability of the CD process. Several CD experiments were conducted in the bench scale and pilot scale CD facilities at the University of Waterloo. These experiments provided operating data for a variety of liquid flow rates and catalyst bed heights. It was also verified that the CD process can exceed the equilibrium conversion of acetone, as a product containing 50 wt% DAA was easily obtained. A differential rate-based model was developed which describes the reaction zone of the CD column. The model takes into consideration the kinetic data obtained in the absence of external mass transfer and modifies the kinetic equations to incorporate the various types of external mass transfer which exist in the CD column. The model was fitted to the CD operating data so that the rate of DAA production predicted by the model matched the experimental data. Agreement between the model and other experimental variables which were not fitted was very good. The predicted flow patterns were in agreement with the earlier work of Porter and Templeman (1968), and the model was also able to provide a good estimate of the expected product selectivity and MO production rate. Several samples from within the catalyst bag were also taken, and they confirmed that the predicted concentration profiles in the catalyst bag were close to measured values. Several experiments were conducted with a proper liquid distributor located just above the catalyst zone of the column. Improving the liquid distribution over the catalyst bag resulted in 45-240% gains in DAA production and 112-343% gains in product selectivity (measured as mol DAA/mol MO). The distributor also reduced the variability of the system. Clearly, liquid distribution and mass transfer are two of the most important issues in catalytic distillation. A major problem encountered with this process is catalyst deactivation. If a catalyst can be found that has improved lifetime characteristics, the production of DAA with Catalytic Distillation could easily be commercialized.
Formation of polymer coatings by electropolymerization
(University of Waterloo, 1998) Ling, Xiaoping
Applications of orthonormal bases of wavelets to deconvolution
(University of Waterloo, 1997) Corbett, Norman Christopher
Convolution integral equations arise frequently in many areas of science and engineering. If the kernel of such an equation is well behaved, say integrable, then the task of solving a convolution equation is ill-posed. Indeed, if the kernel is integrable, then the Riemann-Lebesgue Lemma implies that the recovery of high frequency information pertaining to the unknown function will be difficult, if not impossible. Orthonormal wavelet bases are bases generated by translating and dilating a single function, known as the mother wavelet. One key advantage of these bases is that the mother wavelet can be selected to have fast decay in both the time and frequency domains. This property suggests that wavelet bases may be useful when attempting to solve a convolution equation. In this thesis, we investigate the applicability of orthonormal wavelet bases with regard to solving convolution equations. In particular, we concentrate on the construction of approximations to the unknown function belonging to scaling function subspaces. We also briefly consider regularization algorithms which are based on the multiresolution analysis, a structure defined by the scaling function association with the mother wavelet.
Making babies, representations of the infant in 20th century Canadian fiction
(University of Waterloo, 2001) Sabatini, Sandra
This thesis traces infant representation in Canadian fiction throughout the 20th century and focuses on the tension between writing that depicts the infant as a site of desire and as a site of constraint. The tension is particularly and persistently evident in writing by women. The study is contextualized in terms of social and historical developments concerning the infant and explores the impact of feminism and shifting social mores in the expression of the figure of the infant. This impact is evident in the different in kind of infant representation produced by men and women. Writing by men about babies moves in a linear direction, manifesting a change in male protagonists who view the infant idealistically, if at all, to a more distant view in mid-century. Finally male writers return at the end of the century to a consideration of the infant as a source of meaning and value. Women's writing, on the other hand, reveals an intensifying complexity as women come to terms with increasing candour about the contradictory nature of their engagement with the baby, that other subjectivity that they grow inside them. The thesis inquires into the nature of the other subjectivity whom Hannah Arendt has called "the hope of the world."
Experimental investigation of large spring-supported thrust bearings used in hydroelectric generators
(University of Waterloo, 2000) Yuan, John Haojiang
Large spring-supported thrust berings are key components in hydroelectric generators and have not been considered in much detail in the academic literature. The present thesis describes the application of a comprehensive commercial software package (GENMAT) to provide numerical predictions of spring-supported thrust bearing performance. A minor study of the accuracy of the pad deflection model in the software package was performed with a finite element analysis but the issues of accuracy were not resolved. GE Hydro's unique test facility for large thrust bearings was commissioned and extensive experimental measurements of film thickness, pad temperatures and film pressures were collected and compared with numerical predictions of GENMAT. The agreement was good for the temperatures and the shape of the pad but somewhat erratic for film thickness and poor for pressures. The film thicknesses had been measured with effy current displacement probes and their output voltage relationships to target distance, temperature, pressure and target material were characterized in subsequent laboratory experiments. Although probe calibration was implicated in the accuracy of the film thickness measurements, other unknown factors also contributed. An argument was made for accepting GENMAT predictions of film thickness for a given case, provided the temperatures and pad shapes showed good agreement. The neglect of rotor crowning was suggested as an explanation for the poor agreement of the pressures. A combination of theoretical and experimental investigation was performed on a large number of cases. It was found that minimum film thicknesses were always about 15-20 um despite considerable variation in geometry, lubricant viscosity, loads and rotor speeds. Temperature was influenced more readily by these variations, thus suggesting that energy efficiency which depended to a large extent on lubricant temperatures could be improved while maintaining adequate film thickness. Recommendations were made for more extensive application of the GENMAT package to the design of better spring-supported thrust bearings.
Integrating passive microwave remotely sensed imagery and gridded atmospheric data, a study of North American Prairie snow cover
(University of Waterloo, 2001) Derksen, Christopher Peter

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