title: The Crystal Chemistry and Bonding In Vanadates of Divalent Metal Ions And the Crystal Structure of Whitlockite

contributor:
Calvo, C.
Chemistry

subject: crystal structures, CA3(VO4)2, CA3(AsO4), alphaZn3(VO4)2, alpha-Zn2V2O7, Mg2V2O7, VPO5, whitlockite

abstract: The crystal structures of Ca3(VO4)2, Ca3(asO4)2, alpha-Zn3(VO4)2, alpha-Zn2V2O7, Mg2V2O7, VPO5, and whitlockite (Room temperature and 1200 degree C) have determined by X-ray diffraction methods. Tests on the existing theories on the prediction of bond lengths have been made on the vanadate structures determined in this work as well as other reported structures. The range of validity of these theories have been brought out. The importance of the difference of the structure of whitlockite from that of BetaCa3(PO4)2, have also been discussed in detail.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Cross-Flow-Induced Vibrations Deep Inside a Closely-Packed Tube Bank

contributor:
Weaver, D. S.
Mechanical Engineering

subject: Heat exchangers, tube vibrations, shell side fluid flow, vibrations, closely packed tube

abstract:
 Heat-exchangers designed and fabricated in accordance with the existing design standards may be susceptible to damage as a result of excessive tube vibrations caused by the shell-side fluid flow. The present investigat ion was undertaken to further our understanding of the vibration behaviour of tube arrays.

 An experimental facility and techniques have been developed by means of which the major mechanisms that cause flow-induced vibrations in tube arrays due to cross-flow can be produced and properly identified.

 The experiments were conducted in a low-speed windtunnel having 305 x 305 mm.working section. The tube-bundle was a parallel-triangular tube-array with pitch/diameter = 1.375 . The array was 27 rows deep with 5 tubes in each row . The tubes were designed such that they could be conveniently removed from outside the wind-tunnel, in order to facilitate studying the effect of tube-bundle size on vibration and flow characteristics . Nineteen identical tubes in the middle of the tube-array were movable and specially designed so that natural frequency and damping could be controlled precisely over a range of values.

 The experiments have verified that deep inside a closely-packed tube-bank the existence of discrete vortex shedding is not a working hypothesis and the response of a tube in a tube-bundle is expected to be a function of Reynolds number and the number of upstream rows of tubes. From the flow-field velocity power-spectra obtained for the array tested and from the available data existing in the literature, it is seen that there is a strong possibility of predicting the dominating frequency in the flow from a universal Strauhal number. For the first time a fluidelastic stability boundary for the array has been derived and it is noticed that the slope of this boundary is significantly different from that derived by other authors from theoretical considerations.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Studies on the RNA and RNA Complexes Produced by Vesicular Stomatitis Virus in Mouse L-Cells

contributor:
Prevec, Ludvic A.
Biology

subject:
vesicular stomatitis
virus
viral RNA
mouse L-cells
defective particle interference

abstract: Scope and Contents: Virus specific RNA components of the cytoplasmic extracts of cells infected with the Indiana serotype of vesicular stomatitis virus were examined. Studies were carried out both in the presence and absence of defective particle interference.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Character and Origin of the Soil Tongues in the Burford Loam

title: Soil Tongues In The Burford Loam

contributor:
Bunting, B. T.
Geography

subject: soil tongues, Burford loam soils, S. W. Ontario, micromorphological, climate

abstract: A pedological investigation was made of the soil tongues in the Burford loam soils of S. W. Ontario. The purpose of the study was to determine the characteristic features of the soil tongues. The physical and chemical properties of a number of soil tongues were determined and one was used for a micromorphological investigation. Measurements of horizontal and vertical extent were also made. Discussion of the various hypotheses that might account for soil tongue development is included. Evidence for a periglacial climate is given and also f'or the existence of two distinct types of soil tongues.

abstract: Thesis

abstract: Master of Science (MSc)


title: A Self-Consistent "Realistic" Pairing Theory with Applications to Two-Nucleon Transfer Reactions

contributor:
Volkov, A. B.
Physics

subject:
nucleon-nucleon interaction
Skyrme Hartree-Fock solution
pairing theory
two-nucleon transfer
rotational nuclei

abstract: Scope and Contents: A generalized pairing theory has been developed which diagonalizes matrix elements of the effective nucleon-nucleon interaction in a space of one, two and three-pair excitations from a Skyrme Hartree-Fock solution for deformed rotational nuclei. The "pairing" excitation energy for the configurations of time-reversed pairs of particles is obtained from the Hartree-Fock approximation as opposed to the conventional (BCS) residual interaction point of view. The effects of the finite-range character of the effective nucleon-nucleon interaction are studied in the single-particle structure they induce in the pairing matrix elements. Microscopic form factors for (p,t) and (t, p) reactions between states of the rotational bands built on the K^π=0^+ pairing solution band-head states are constructed in the cylindrical Harmonic-Oscillator basis in which the Hartree-Fock solution is expanded. These form factors are used in DWBA calculations for the differential cross-sections. Preliminary calculations for (p,t) and (t,p) transitions between states in 172Yb and 174Yb were performed. The calculations emphasize the effects of structure in the pairing matrix elements, and the necessity for a self-consistent calculation of the diagonal pairing matrix elements sing the Hartree-Fock equations.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A New Algorithm for Stochastic Approximation

contributor:
Sinha, N.K.
Electrical Engineering

subject: stochastic, algorithm, approximation, convergence, optimization

abstract: A review of Stochastic Approximation and the major contributions to the area is made. A proof of convergence for the algorithm is developed. An optimization is attempted on the rate of convergence problem and the uniqueness problem is faced. An alternative proof of convergence is given as an independent check on the first one. Simulation results are present in light of the theory developed, and conclusions, limitations and recommendations are presented.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Characteristic and Order for Polynomial Differentiability

contributor:
Lane, N.D.
Mathematics

subject: polynomial, order, differentiability, plane, intersection, integers, sum

abstract: A definition of polynomial differentiability of an arc in the real affine plane at a point is given. The differentiable points are classified with respect to the intersection and support properties of certain families of osculating polynomials. For a given point of an arc, these properties are used to define a certain n-tuple of integers, the characteristic of that point. It is shown that the polynomial order of polynomially differentiable interior point of an arc is at least as great as the sum of the digits of its characteristic.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Effective Field Theories for Metallic Quantum Critical Points

contributor:
Lee, Sung-Sik
Physics and Astronomy

subject:
Quantum Phase Transition
Metals
Non-Fermi Liquid
Renormalization Group

abstract:
In this thesis we study the scaling properties of unconventional metals that arise at quantum
critical points using low-energy effective field theories. Due to high rate of scatterings between
electrons and critical fluctuations of the order parameter associated with spontaneous symmetry
breaking, Landau’s Fermi liquid theory breaks down at the critical points. The theories that
describe these critical points generally flow into strong coupling regimes at low energy in two
space dimensions. Here we develop and utilize renormalization group methods that are suitable
for the interacting non-Fermi liquids. We focus on the critical points arising at excitonic, and
commensurate spin and charge density wave transitions. By controlled analyses we find stable
non-Fermi liquid and marginal Fermi liquid states, and extract the scaling behaviour. The field
theories for the non-Fermi liquids are characterized by symmetry groups, local curvature of the
Fermi surface, the dispersion of the order parameter fluctuations, and dimensions of space and
Fermi surface.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Equilibrium Fractionation of Sulfur Isotopes Between Pyrite, Sphalerite and Galena as a function of Temperature.

contributor:
Schwarcz, H. P.
Geology

subject: fractionation, Sulfur Isotopes, sulfide mineral, mineraelogy, temperature, equilibration, sphalerite, pyrite, galena, sulfide phases, geothermometers, sulfide, mineral pair, Kinetic isotope effect, Diffusion, Thermal Diffusion, Solid Diffusion, Cross-Over Temperature, Pressure, Ideal Gas Assumption, Anharmonicity, Intra-molecular Fractionation,

abstract: The existence of significant and consistent fractionation of sulfur isotopes in natural coexisting sulfide mineral pairs is demonstrated. Such fractionations are shown to depend exclusively on the mineralogy of the assemblage and temperature of equilibration, consistent with a process of fractionation during equilibrium exchange of sulfur isotopes between the sulfide phases . The fractionation of sulfur isotopes between galena, sphalerite and pyrite has been determined experimentally over the temperature range 300-725°C . The fractionation for each mineral pair is shown to vary as T^(-2) so that three isotope geothermometer s have been calibrated. Experi mental results are applied to natural sulfide assemblages to determine the temperature of equilibration and extent to which isotopic equilibriurn has b een attained.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A: Alpha-Activity of Natural Samarium B: A Search for Neutronic Nuclei

subject: alpha-activity, samarium, neutronic, nuclei, energy, decay

abstract:
 The alpha-activity of natural samarium has been studied using an ionization chamber. A gridless ionization chamber has been developed in order to obtain high resolution and high sensitivity. The half lives and the energies of the alpha decay of Sm147 and Sm148 were measured where as the alpha-activity of Sm149 and Sm146 could not be detected.

 Experiments were carried out in order to search for the existence of Particle stable neutron clusters in the range of Mass 6-10 as a component of a nuclear reactor flux and as the product of high energy proton spallation of heavy nuclei.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Cobble Beaches Along The Coastlines Of The Georgian Bay Islands

contributor:
McCann, S.B.
Geography

subject: fresh water, cobble beaches, Georgian Bay Islands, morphological, sedimentary provenance, costal, Lake Huron, backwash

abstract:
 This report is the only detailed study concerning the fresh water cobble beaches of the Georgian Bay Islands. It includes extensive studies on the morphological characteristics, especially the platform development and profile configuration, and the sedimentary provenance of the cobbles.

 It was found that the platform configuration (step topography) acts as a substrate control for the cobble beaches. The presence of two cobble generations, angular and well-rounded, indicate that t he shore platform is the source for these cobble beaches.

 The roundness values of these cobble generations depends on t heir mode of transport. Evidence indicates that longshore movement of cobbles increases their roundness values, but their angular shape i s indicative of their lack of transport.

 Very little proof was found within this study to correlate relict cobble beaches with any specific stage of the Lake Huron Basin, although it was possible to generalize and state that the relict cobble beaches were generated by high-energy wave events during the transition from the Algoma stage to Lake Huron.

 Clast analysis determines the relationship between the length of the wave fetch and its related energy environment. It was found that high-energy coastal environments have oblate cobbles with a high roundness and low sphericity. In each case, the samples were associated with a large fetch. Those cobbles of a low-energy coastal environment have a high sphericity, low roundness, and are associated with smaller fetches.

 The steepness of the beach profile results from the increase in wave height, generated by an increase in shallowness. It also depends upon the volume of backwash. The backwash is reduced by the increased percolation rates through the cobbles, thus reducing the combing down effect of the backwash.

 This study also provides a discussion on the minor morphological features such as sinkholes and imbrication.

abstract: Thesis

abstract: Bachelor of Arts (BA)


title: Coupled Neutronic-Thermalhydraulic Transient Behaviour of a Pressure Tube Type Supercritical Water-cooled Reactor

contributor: Engineering Physics and Nuclear Engineering

subject: SCWR Neutronics Thermalhydraulics Coupling

abstract:
The Generation IV International Forum has established several goals for the next
generation of nuclear energy systems, which are to be substantial improvements
over contemporary designs. In Canada Generation IV research efforts have
focused on developing the Pressure Tube type SuperCritical Water-cooled
Reactor (PT-SCWR), an evolution of CANada Deuterium Uranium (CANDU)
technology. An integral part of the PT-SCWR is the High Efficiency Re-entrant
Channel (HERC), wherein coolant first travels downward through a centre flow
tube and then upward around the fuel. The large density variation of
supercritical fluids, combined with the negative Coolant Void Reactivity (CVR),
make the concept similar to a Boiling Water Reactor (BWR). The objective of this
study was thus to apply the state-of-the-art in BWR analysis to the PT-SCWR.
Models were created using the DRAGON (neutron transport), DONJON
(neutron diffusion/spatial kinetics), and CATHENA (channel thermalhydraulics)
computer codes. A procedure for DONJON-CATHENA coupling was developed
to enable simulation of coupled transients. The specifications of the HERC
necessitated multiple coolant reactivity feedbacks be included in the model, in
turn requiring extensions to the DONJON source code. The model created for
this work is thus among the first to incorporate multiple coolant feedbacks in
core-level coupled spatial kinetics and thermalhydraulics transient analysis, and
is uniquely capable of simulating such transients in the PT-SCWR.
This work found that while the total CVR was negative as required, the reactivity
effect of coolant void solely around the fuel was positive. As a consequence
additional heat delivered from fuel to coolant, which decreases the coolant
density, has a positive reactivity effect making BWR-like coupled instabilities
impossible. On the other hand, in some postulated transients, such as Loss-OfCoolant Accidents (LOCAs) or Loss-Of-Flow Accidents (LOFAs), this positive
reactivity results in temporary power excursions. A fast-acting shutdown system
is potentially necessary to limit damage to the fuel in such transients.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: Conversational, On-Line Computing with the 'OPTISEP' Subroutines

contributor:
Newcombe, W.R.
Mechanical Design

subject: computing, on-line, OPTISEP, subroutines, optimization, conversational

abstract:
 An examination of the Man-Machine interface as found in the Designers Computer aided optimization techniques OPTIPAC/OPTISEP is first presented. Several guidelines for the implementation of an improved interface using a time-shared computer system are then described.

 A graphic means of assessing the behaviour of an optimization problem's objective function and the various constraints acting upon it is then outlined in the form of the subroutine OPTPLOT. Several sample plots involving the optimization of system reliability are then generated using a conversational programming technique.

 The same programming technique is then applied to the OPTISEP series of subroutines and a demonstration of the system using the previous sample problem is included.

 A hypothetical, but truly interactive system is then postulated and the possibilities for its implementation at McMaster with the facilities presently available are outlined.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Film Thickness Monitor for the Controlled Evaporation of Vacuum Deposited Films

contributor:
Campbell, C. K.
Electrical Engineering

subject: film thickness, thin film thickness, resonant, substrate, crystal geometry, resonating quartz crystal

abstract:
 A thin film thickness monitor has been designed and constructed based on the "mass loading" effect of a resonant quartz crystal. A 6.0 MHz Y-cut crystal, having a theoretical "mass determination sensitivity" of 8.15x10^7 Hz. - cm^2/gm, serves as the sensor element. This sensitivity can be closely approached in practice if the entire active area of the quartz plate is exposed to the evaporant stream. However, due to source, substrate and crystal geometry the "effective" sensitivity of the monitor is only 0.433 of the above value.

 Both film thickness and deposition rate can be measured by the monitor in terms of equivalent frequency changes. The actual thickness and rates depend upon the density of the evaporant. In the case of silver (density 10.5 gm/cm^3), the monitor measures average thicknesses from several (oA) to 1.36 microns in one single deposition. Each crystal can be used to monitor a total of 4.5 microns of silver before replacement. Deposition  rates for silver can be measured from as low as 0.l (oA)/sec to 1360 (oA)/sec.

 By combining the thickness monitor with apparatus for controlled evaporation, a system was set up which can control film thickness to within 2% and deposition rate to within 5%.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: ADVANCING THE USE OF MOBILE MONITORING DATA FOR AIR POLLUTION MODELLING

contributor:
Kanaroglou, Pavlos
School of Geography and Geology

subject:
Air Pollution
Spatial Analysis
Particulate Matter

abstract:
Air pollution is highly variable in both space and time, which presents many challenges to researchers when they wish to model concentrations. The modelling of air pollution is necessary for a number of reasons, which include the determination of human health effects, providing warning of health risks, and to understand general ecosystem health. In this thesis, modelling of air pollution through both space and time has been explored, with a focus on improving models that can be used to assign air pollution exposure. The techniques presented in this thesis have leveraged the ability of mobile monitoring units to collect air pollution concentration data multiple locations throughout a study period. First, we explore the use of combining mobile air pollution monitoring data with traditional fixed location monitoring. We find that the mobile data is able to provide insight into changes in spatial pattern between two temporal periods that could not be identified solely with the fixed location monitors, which demonstrates value in this monitoring approach that can be built upon with refinement of techniques. Second, we present a method to determine the amount of classical error that will be introduced when a long-term mean concentration is calculated from a discontinuous time-series dataset, which are the type of datasets collected by mobile air pollution monitoring. Third, we merge mobile and stationary air pollution monitoring data, along with meteorological, transportation, and land use information to model the hourly air pollution field using neural network models. The models developed allowed for the assignment of air pollution exposure incorporating human activity patterns. Also, they can be used to provide a spatially refined air quality health index. Lastly, we demonstrate exposure assignment that incorporates human activity patterns to calculate the dose exposure for students during their trips to school.
This work commences with a demonstration of the basic utility of mobile air pollution monitoring data, which is to increase the number of monitored locations. Building on that utility of mobile technology, a technique was developed to estimate the error when mobile units are used for long-term estimates, similar to stationary monitoring units; and we were able to provide guiding principles for mobile monitoring data collection. Furthering our objective, to better understand the value of mobile data in a fully integrated monitoring network, we utilized both mobile and stationary data collection techniques together, in a single model, to produce accurate estimates of an air pollution field on an hourly basis. Finally, the research culminates with the demonstration of how mobile monitoring can be used for activity based air pollution exposure estimates, which was shown with a case-study of students’ trips between home and school. Overall, the chapters in this thesis work toward a better understanding of how to incorporate mobile monitoring data into air pollution assessment studies.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Production and manipulation of two dimensional droplet aggregates

contributor:
Dalnoki-Veress, Kari
Physics and Astronomy

subject:
emulsion
droplet production
order
disorder
micropipette deflection
force measurement

abstract:
This is a `sandwich thesis' comprising three distinct research streams I have pursued during the course of my master's degree. The  first two streams have concluded, each resulting in a manuscript that is presented as a separate chapter of this thesis. The third research stream is ongoing, but preliminary results are presented in another chapter of this thesis.
The  first research stream presented in this thesis concerns the development of a technique to produce droplets with diameters as small as 5  microns with an extremely narrow size distribution in comparison to other methods. Other advantages of this technique, known as  he snap-offf method, include its simplicity and ease of tuning droplet size. The results of this research are presented in chapter 3 in the form of a manuscript that is currently in press.
The second research stream of this thesis explores the physics that drive droplet snap-off. A model was developed to predict the size of droplets, dependent on  fluid properties, system geometry, and  fluid flow rate. Experiments examined each of these parameters in turn, providing a cohesive understanding of the mechanism behind droplet snap-off. Multiple  unanticipated predictions of the model were also verified experimentally. This research is presented in chapter 4 as a manuscript that will be submitted shortly.
The  final research stream of this thesis investigates forces in emulsions as they relate to a transition from glassy to crystalline dynamics. Specifically, 2D aggregates of droplets were compressed with micropipettes, providing both imaging of cluster evolution, as well as the force applied during compression. This research stream has demonstrated qualitative differences between droplet clusters that differ in composition so as to behave like crystals, glasses, or intermediate states. More quantitative analysis is required before this research stream is ready to be published. Preliminary results are presented in chapter 5.

abstract: Thesis

abstract: Master of Science (MSc)


title: Ableism, racism and colonialism in Canadian Immigration: Exploring constructions of people with disabilities

contributor:
Carranza, Mirna
Social Work

subject:
Ableism
Racism
Sanism
Disability Activism
Immigration
Colonialism
Norht/South Power Relations
Critical Discourse Analysis
Knowledge Production
Social Work

abstract:
Abstract
This dissertation reports on the findings of a study that set out to examine how discourses of ableism, racism and colonialism shape Canadian immigration policies, and settlement practices.  This research examined how these discourses contribute to constructing immigration applicants with disabilities as an inadmissible social group.  With a focus directed to the application process as a key knowledge gap in the intersection of disability and immigration, I launched this study with the aim of answering the following main research question: “How do discourses of ableism, racism and colonialism construct immigration applicants with disabilities?
Through a critical discourse analysis study of official Citizenship and Immigration documents as well as episodic interviews with 23 participants (immigrants with disabilities, family members, and service providers), findings demonstrate the importance of understanding immigration as a continuum from pre-application to settlement.  I argue that the immigration process is shaped and defined by central discourses that construct immigration as an opportunity for a better life through which ableist, racist and colonial discourses are reflected and reinforced.  Social workers and other helping professionals involved in settlement services for immigrants with disabilities play significant roles in how discourses of opportunity are actualized and materialized.  The dissertation ends with implications for critical research, theory and social work practice.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract:
Lay Abstract
This study looked at the ways in which immigration and disability intersect and what this means for social work practice, policy and research.  Through a Critical Discourse Analysis of official immigration documents and interviews with immigrants with disabilities, family members and service providers, the study examined the pre-application and application stages of immigration, as well as settlement issues.  The main finding of the study is that discourses of opportunity are central in shaping these stages, while reinforcing ableism, racism and colonialism.  Implications for future research, policy and practice are laid out to push for a social work role that moves beyond applying oppressive policies and practices to being more in line with principles of social justice.


title: Chlorides and Oxochloride Complexes of Rhenium

contributor:
Lock, C.J.L.
Chemistry

subject: rhenium, chlorine, complexes, compound, cells, structures

abstract: A brief review of the rhenium-chlorine system is presented and a method to determine rhenium:chlorine atom ratios by neutron activation analysis is described. An infrared cell which is useful for highly re-active vapours at temperatures up to 400°C is also described. The compound claimed to be rhenium hexachloride is shown to be rhenium oxytetrachloride and a reliable preparation of β-rhenium tetrachloride is discovered. The hexachlororhenate(V)ion and several complexes containing rhenium(V), rhenium(VI) and rhenium(VII) are prepared. Chemical and physical evidence is used to predict structures of some of the above compounds.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: On the Expectations of Certain Order Statistics

contributor:
Banerjee, S.K.
Mathematics

subject: order, statistics, functions, bivariate, quartiles

abstract: This thesis deals with order statistics and the asymptotic distributions of certain functions of the first and second quartiles of a sample drawn at random from a bivariate population, whose distribution function is specified by its truncated bivariate Edgeworth Series.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Ideal Roman Daughter through the Life Course: Three Case Studies

contributor:
George, Michele
Classics

subject: Roman social history, history of the family, Roman women

abstract: The following thesis is a collection of three case studies which shed light on the ideal roles of a daughter in the Roman family over the course of her life. Plentiful recent scholarship on children in the Roman world exists, but few scholars have focused exclusively on girls and women qua daughters. The case studies are centred on epistolary sources which span the late Republic to the second century CE. The chapters of this thesis concern Timoxena, the two-year-old daughter of Plutarch; Minicia Marcella, the teenage daughter of Fundanus; and Tullia, the adult daughter of Cicero. These case studies will illustrate primarily that adult behaviours were constantly idealized throughout the life course of a daughter, but the expectations for a daughter did change to accommodate the actual age of the daughter concerned. In addition, the ideal behaviours expected of a daughter did not necessarily become more gendered as she grew older and became a full member of society, but her contribution to the bond of reciprocal obligation with her parents, dictated by pietas, was expected to intensify as she matured.

abstract: Thesis

abstract: Master of Arts (MA)


title: Lanthanide Abundances in Coexisting Skarn Minerals, as Determined by X-Ray Fluorescence Analysis

contributor:
McNutt, R.H.
Geology

subject: elements, x-ray, fluorescence, minerals, lanthanides, skarn, abundances

abstract:
 A method is presented for the determination of trace quantities of the rare earth elements and yttrium in calcareous minerals by X-ray fluorescence analysis. Initial chemical concentration of the rare earths is accomplished by scavenging their insoluble hydroxides on a ferric hydroxide precipitate and serves the further purpose of elimination of matrix absorption effects which dampen sensitivity when the raw minerals are analysed.

 Triplicate analyses are given for La, Ce, Sm and Y in a calcite-fluorite-apatite skarn rock and for each of the three minerals of this rock. Apatite and calcite are enriched in all the rare earths investigated relative to the whole rock, while fluorite shows a relative depletion. The apatite is enriched in the rare earths relative to the calcite. Peak height ratios of Nd, Eu, Er, Lu, Gd+Ho and Dy+Tm in each of the separated minerals to the whole rock show the same trends as the quantitative data and also indicate that apatite and fluorite show a stronger affinity for the lanthanides of low atomic number than for those of higher atomic number. The abundances of the rare earths in the apatite show the same dependence on ionic radius as has been noted by other workers. The whole rock and each of the minerals which it contains are enriched in all the rare earths relative to chondrites.

 The rare earths have preferentially entered the lattices of those minerals which provide a stronger rare earth-anion bond.

abstract: Thesis

abstract: Bachelor of Science (BSc)


title: On the Generalized Dirichlet Problem

contributor:
Jackson, H.L.
Mathematics

subject: dirichlet, problem, Euclidean, functions, generalized

abstract: In this thesis, we shall solve the classical Dirichlet problem for a ball in n-dimensional Euclidean space, and then point out that the classical Dirichlet problem is not always solvable. Following Wiener and Brelot, we then introduce a generalized Dirichlet problem for any bounded region in n-dimensional Euclidean space and establish necessary and sufficient conditions for its solution. We show that the solution of the generalized Dirichlet problem coincides with the solution of the classical Dirichlet problem whenever the latter exists. Finally, we characterize those regions for which the classical Dirichlet problem is solvable by considering the boundary behaviour of those functions for which the generalized problem is solvable.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Nucleation of Nickel Dioximates From Aqueous Solution

contributor:
Hileman, O. E.
Chemistry

subject: liquid droplet nucleation, vapours nucleation, crystal nucleation, aqueous solution, crystals

abstract:
 A brief review of the theoretical and experimental aspects of liquid droplet nucleation from vapours and of crystal nucleation from aqueous solution is presented. In order to study the nucleation and crystal growth of several analytically important metal chelates, methods were developed to measure the size distribution of crystals growing in a supersaturated solution. These methods involved rapid mixing techniques followed by measurement of the size distribution of the precipitated particles using a Coulter counter and multichannel analyser. The size distributions were dumped from the analyser onto magnetic tape and recovered using computer methods. The mixing and counting techniques were calibrated and tested using barium sulphate and spheres of known size distribution.

 From the size distributions obtained for the metal chelates, conclusions were made regarding the nucleation step, and the parameters important in the classical Volmer-Weber-Becker-Doring theory of nucleation were calculated. The validity of the values were evaluated and comparisons made with values obtained by other workers.

 The laws controlling the crystal growth of the metal chelates and their importance in elucidating the type of nucleation process were also investigated.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Modelling Young Star Clusters with AMUSE

contributor:
Sills, Alison
Physics and Astronomy

subject:
star cluster
modelling

abstract:
An important research area in modern astrophysics is understanding how molecular clouds form stars and star clusters. These rich clusters within molecular clouds are the dominant mode of star formation in our galaxy, but we know very little about these areas of space due to incomplete observational data. The MYStIX (Massive Young Star-Forming Complex Study in Infrared and X-Ray) project was started to create a detailed catalogue of these regions and the rich star clusters embedded within them. Once the observational data was available, the evolution of these clusters could be investigated in more detail. Current cluster simulations investigate the stars in detail but usually ignore the gas entirely which can be inaccurate, especially in gas mass dominated clusters. We use AMUSE (Astrophysical Multi-purpose Software Environment) to model embedded young clusters with stars and gas, similar to those found by the MYStIX project, and track their evolution over the  first few million years of their lifespan while allowing the stars and gas to interact. We are particularly interested in non-spheroidal subclusters and how they can evolve into the spherical
structures that we see today.

abstract: Thesis

abstract: Master of Science (MSc)


title: Calculation of Phonon Frequencies and Widths in Cu0.97A0.03 Alloy

contributor:
Taylor, D. W.
Physics

subject: mass defect, light defect, heavy defect, crystal, gold defects, copper, Copper-Gold Alloy

abstract:
 The mean square displacement spectrum of a single mass defect and that of its neighbours is examined for both a light and a heavy defect to observe the extent of the perturbation of the pure crystal.

 Nearest neighbour force constant changes for a 3% random distribution of gold defects in a copper host are calculated by fitting to experimental elastic constants for this alloy. The phonon shifts and widths are calculated for the system with various sets of force constant changes, and comparison is made with experiment.

abstract: Thesis

abstract: Master of Science (MSc)


title: Nuclear Magnetic Resonance Studies of Boron Trifluoride and Some of its Complexes

contributor:
Gillespie, R.J.
Chemistry

subject: nuclear, magnetic, resonance, complexes, stoichiometry, Boron

abstract:
 Nuclear magnetic resonance spectroscopy has been used to study donor-acceptor complexes of boron trifluoride with ketones, water, and methanol. Various NMR techniques have been applied which, in certain favourable cases, have yielded information on the stoichiometry, structure, relative stabilities, and reactions of the complexes in solution.
A new method is proposed for the detection of BF3 complexes having low formation constants.

 The magnitude and sign of the B-F coupling constant in the tetra-fluoroborate
anion have been found to be dependent on the solvent. This solvent dependence is interpreted in terms of solvation and association of the ion in solution.

 19F spectra of 10BF3 over a range of temperatures agree well with line shapes calculated, using Pople's expressions, for coupling of fluorine-19 with boron-10 (I=3) which is undergoing partial quadrupole relaxation.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Malaria Control: Insights from Mathematical Models

contributor:
Dushoff, Jonthan
Biology

subject:
Malaria
Mathematical models
Bistability
Heterogeneity
Basic Reproductive Number

abstract:
Malaria is one of the most devastating infectious diseases, with nearly half of the worlds population currently at risk of infection. Although mathematical models have made significant contributions towards the control and elimination of malaria, it continues to evade control. This thesis focuses on two aspects of malaria that complicate dynamics, helping it persist.
The basic reproductive number is one of the most important epidemiological quantities as it provides a foundation for control and elimination. Recently, it has been suggested that R0 should be modified to account for the effects of finite host population on a single disease-generation. In chapter 2, we analytically calculate these finite-population reproductive numbers for both vector-borne and directly transmitted diseases with homogeneous transmission. We find simple, generalizable formula and show that when the population is small, control and elimination may be easier than predicted by R0.
In chapter 3, we extend the results of chapter 2 and find expressions for the finite- population reproductive numbers for directly transmitted diseases with different types of heterogeneity in transmission. We also outline a framework for discussing the different types of heterogeneity in transmission. We show that although the effects of heterogeneity in a small population are complex, the implications for control are simple: when R0 is large relative to the size of the population, control or elimination is made easier by heterogeneity.
Another basic question in malaria modeling is the effects of immunity on the population- level dynamics of malaria. In chapter 4, we explore the possibility that clinical immunity can cause bistable malaria dynamics. This has important implications for control: in areas with bistable malaria, if malaria could be eliminated until clinical immunity wanes, it would not be able to invade. We built a simple, analytically tractable model of malaria transmission and solved it to find a criterion for when we expect bistability to occur. Additionally, we review what is known about about the parameters underlying the model and highlighted key clinical immunity parameters for which little is known. Building on these results, in chapter 5, we fit the model developed in chapter 4 to incidence data from Kericho, Kenya and estimate key clinical immunity parameters to better understand the role clinical immunity plays in malaria transmission.
Finally, in chapter 6, we summarize the key results and discuss the broader implications of these findings on future malaria control.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Subgroups of Adolescent Girls with Borderline Personality Disorder Symptoms

contributor:
Boylan, Khrista
Neuroscience

subject:
Borderline Personality Disorder
Depression
Self-injury
Unstable mood

abstract:
This thesis examined the borderline personality disorder symptom profiles of teenage girls who were referred to a tertiary child and youth psychiatry clinic. Self-injury and unstable mood are key features of Borderline Personality Disorder (BPD) but are also associated with other disorders such as depression and anxiety disorders. The aim of the larger study was to determine whether BPD can be differentiated from other disorders in a highly comorbid adolescent sample who self-injure.
To answer this question, individuals in our sample were grouped based on the pattern of BPD symptom endorsement using a latent class analysis. The subgroups that emerged from our sample were then compared to each other across other clinical measures. Four latent classes were identified. The most impaired class had a high prevalence of BPD (70%). An intermediate class had a significantly higher prevalence of PTSD (41.7%). Another intermediate group had a higher prevalence of anxiety disorders (62%) (Social Phobia and Generalized Anxiety Disorder). The largest class had a low prevalence of all psychiatric disorders.
The results indicated that only a small subset of teenage girls who presented with self-injury and unstable mood met criteria for BPD. These girls represented a distinct and severely impaired group with high comorbidity. The subgroups that emerged from our sample provide guidance to clinicians regarding the likelihood of a personality disorder diagnosis in this population and the pattern of emotional difficulties of youth who self-injure.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Distribution of Manganese in Blood

contributor:
Fritze, K.
Chemistry

subject: manganese, blood serum, erythrocytes, radioactive tracer method, gel chromatography, disc gel electrophoresis, labile manganese complex, vitro, in vivo

abstract:
 The distribution of manganese in blood serum and erythrocytes has been investigated using a combination of radioactive tracer method with both gel chromatography and disc gel electrophoresis.

 In serum, there are two manganese-binding proteins. The first is a(beta)1 globulin with a molecular weight of 70,000. This forms a relatively labile manganese complex both in vitro and in vivo, and is remarkably similar in both its chromatographic and electrophoretic behaviour to the iron-binding protein, transferrin. The second protein is a higher molecular weight (beta) globulin. It is found to incorporate radiomanganese in vivo only, thereupon forming a very stable entity.

 In erythrocytes, manganese occurs predominantly in a porphyrin bound to apoglobin, giving rise to a species similar to hemoglobin .

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: On the Electrification of the American Muscle Car: An Analysis and Model Based Design

contributor:
Emadi, Ali
Habibi, Saeid
Mechanical Engineering

subject: Electrification Powertrain

abstract:
This report includes a systematic approach to defining and analyzing an electrified powertrain for use in a modern American muscle car. To provide a background and define the problem the current trends in vehicle electrification will be explored followed by a definition of the American muscle car and its technical requirements. To analyze a variety of powertrains across multiple tests, the model based design approach is used with a custom designed simulation tool. Once the simulation environment is understood multiple simulations and tests are performed on each electrified powertrain defined to gain insights into their behavior and characteristics.
Through experimental data and first principals a modeling tool is developed for the specific purpose of powertrain architecture selection. The tool provides many insights, flexible powertrain topologies, and customizable testing procedures. To ensure that the results of the tool are accurate energy balance calculations are performed on each powertrain and a comparison to commercially available software is given. To ensure that the new powertrains are improvements on their respective conventional vehicle counterparts, baseline simulations are completed and compared alongside the electrified vehicle powertrains. A selection matrix is formed to quantitatively compare and selected an appropriate powertrain for an American muscle car and a feasibility study is completed to ensure the design goals are met.

abstract: Thesis

abstract: Master of Applied Science (MASc)

abstract: The American muscle car has made a recent comeback in popularity after many years. The modern muscle car combines classic styling with modern day technology creating a car that is fun to drive and commands attention on the road. With fuel economy and emission standards becoming more stringent, American muscle cars will need to rely on the most recent technology to maintain the performance that excites their owners. To meet these future demands vehicle electrification has proven to be a solution that can greatly increase fuel economy and has also been used in high performance applications. Analysis must be completed to understand each electrification approach and which one is best suited for the muscle car segment. A model based design approach can be used to analyze each powertrain and give insights into each topology. After completing simulations of a variety of powertrains, an appropriate electrified powertrain can be proposed for an American muscle car.


title: Theory of Ultrasonic Attenuation In Metals Due to Interactions With Conduction Electrons

contributor:
Carbotte, J.P.
Physics

subject: electron, linearized Boltzmann equation, conduction electrons, ultrasonic attenuation in metals, electronic structure, electron-lattice, Boltzmann equation, phonon drag effects, anisotropic scattering

abstract:
 Working within the framework of the linearized Boltzmann equation for the conduction electrons the existing theoretical treatments of ultrasonic attenuation in metals are extended to include realistic descriptions of the electronic structure and electron-lattice interaction. A variational solution of the Boltzmann equation which allows the inclusion of phonon drag effects is derived. An anisotropic scattering time solution is also presented. Both of these solutions are applied to calculation of the attenuation coefficient in pure metals and dilute alloys.

 The theory of the effects of electron-electron collisions on the ultrasonic attenuation in metals is also examined.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Field and Stable Isotopic Characteristics of Carbonate Alteration Zones, Timmins Area

contributor:
Crocket, J.H.
Schwarcz, H.P.
Geology

subject: carbonate, Timmins area, isotopic, alteration, fluid

abstract: Page 214 Not included in thesis.

abstract:
 Hydrothermal carbonate was introduced into igneous rock
in the Timmins area during an early, sea water alteration event when calcite (δ13C = 0 to -3o/oo) filled the primary porosity of basalt flows and during a later hydrothermal event when mafic and ultramafic igneous rock were altered into a zoned sequence consisting of an inner zone of ferroan or magnesian carbonate flanked by calcite- and chlorite-rich assemblages. The younger intense carbonate alteration event predated or was synchronous with regional metamorphism and deformation and was focused along structurally induced, permeable zones. Gold was introduced during and after the intense carbonate alteration.

 Away from carbonaceous sediments, δ13C-values of the ferroan carbonate are very uniform (-3.5 to -5o/oo) regardless of stratigraphic position, size, or gold tenor of the alteration zone. As carbonaceous sediments are approached, 13C of the ferroan carbonate becomes upto 4o/oo heavier. The 13C of the CO2 and  δ18O and δD of the water components of the hydrothermal fluid are estimated to have been -3 to -6, +5 to +10, and -40 to -60o/oo respectively. The geological controls on the distribution of carbonate alteration, and the stable isotopic values of the hydrothermal components suggest that the H2O-CO2 hydrothermal fluid was of magmatic origin, a result of mantle degassing.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Effects of Proton Radiation Damage on the Conductance and Temperature Coefficient of Resistance of Reactively Sputtered, Discontinuous Tantalum Thin Film Resistors

contributor:
Shewchun, J.
Electrical Engineering

subject: proton, radiation, resistors, conductance, temperature, thin film

abstract:
 Tantalum thin film resistors have been reactively sputtered in oxygen and nitrogen simultaneously. The films studied had resistivities ranging from 400μΩ-cm to 3 x 10^4 μΩ-cm. The corresponding TCR values ranged from -50 ppm/°C to -2,000 ppm/°C. Conductance-temperature measurements show that electrical conduction in discontinuous films of metallic islands (typically 100 A°) largely surrounded by regions of Ta2O5 (typically 50 A°) may be due to a tunneling mechanism of negative TCR operating concurrently with a metallic mechanism of positive TCR via interconnected metallic islands.

 Irradiation of these discontinuous films by 150 keV protons produces a conductance increase which is attributed to an enhanced tunneling mechanism via electronic defect levels in the inter-island oxide regions. During irradiation of these films at 30°K, the conductance change increases and approaches apparent saturation. This nonlinearity is attributed to a combination of spontaneous recombination and close-pair thermal annealing. The number of unstable sites surrounding each defect is found to be ≥ 4. Thermal recovery of the conductance proceeds in two main stages: Stage A (34°K to 150°K) is attributed to close-pair or correlated recombination; Stage B (150°K to 300°K) is attributed to uncorrelated migration of defects to gap-island interfaces, as is indicated by the greatly reduced Stage B annealing which is observed for continuous, polycrystalline films of Ta2O5, having a typical grain size of 1,500 A°. Negative annealing stages (characterized by a conductance increase) indicate a metallic conduction process via connected metallic islands.

 For 286°K irradiation of discontinuous films, the conductance initially increases with fluence in a nonlinear fashion until a threshold fluence is reached, at which point the conductance decreases with fluence. The nonlinearity of the conductance increase is attributed to trapping of mobile radiation-produced defects at gap-island interfaces during irradiation. The subsequent conductance decrease is attributed to a shift in the Fermi level, and thus the height of the tunneling barrier, as the result of the formation of unequal concentrations of stable radiation-produced donor and aeceptor defects since unequal concentrations of these defects can be expected to annihilate at the gap-island interface. The absence of this conductance decrease in continuous polycrystalline films is consistent with this model, since the absence of gap-island interfaces is expected to result in equal concentrations of stable donor and acceptor levels being produced.

 The observed negative increase in TCR with fluence is attributed to an increase in the proportion of the tunneling mechanism of negative TCR (as the result of radiation-produced defects in the inter-island oxide regions) relative to the proportion of the metallic conduction mechanism of positive TCR. The difference between the TCR recovery after irradiation at 30°K (little recovery between 150°K and 300°K) and the conductance recovery (about 50 percent of the recovery occurs between 150°K and 300°K) is attributed to the expected greater influence of metallic recovery on the annealing of the film TCR relative to the annealing of the film conductance.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Comparison of Techniques Used In Discrimination and Classification

contributor:
Stephens, Michael A.
Statistics

subject: discrimination techniques, statistical, multivariate data, Fisher's Discriminant Function

abstract: Application of four statistical techniques of discrimination is made to a set of multivariate data. The techniques, proposed by R.A . Fisher [6], C.R. Rao Q4] , D.F. Andrews [l] and H. Chernoff [4], are reviewed, applied and criticized in an intercomparison of the four methods. Graphic illustrations are also utilized to aid in the classification of sampling units.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Location and Effects of Factors Controlling Recombination in Linkage Group I of Neurospora

contributor:
Threlkeld, S.F.H.
Biology

subject: recombination, linkage, Group I, neurospora, factors

abstract: It was known, prior to this study, that there is a factor, or factors, in the centromere-proximal region of Neurospora sitophila which affect recombination near the centromere whether it is in Neurospora sitophila or transferred to Neurospora crassa. A location of this factor, or factors, was performed using tetrad and prototroph analysis. Further mapping of linkage group I of Neurospora crassa was undertaken when the Neurospora sitophila centromere-proximal region was present.

abstract: Thesis

abstract: Master of Science (MSc)


title: Comparison Between "PQR" and Direct Elimination Methods of Formulating Power System Coefficient Matrices

contributor:
Alden, R.T.H.
Electrical Engineering

subject: power, systems, linearized, matrices, elimination

abstract:
 In power systems, dynamic stability analysis is an important field of interest for both design and operation studies. This stability analysis requires the formulation of the linearized power system equations in the state-space form.

 In this thesis, the state-space matrices of multi-machine systems are constructed by implementing two matrix formulation techniques, the "PQR" and the direct elimination "ELIM" methods. Two computer programs have been devised to apply these formulation techniques. The programs are capable of handling systems up to a maximum order of 70, with available central memory of about 49,000 words (decimal). Another feature of these programs is their capability of accommodating generating units with different degrees of complexity, by allowing a variety of models for the sub-system components. Both programs have been applied to two test examples to illustrate their validity.

 The two formulation technique programs were compared from the point of view of computational time, storage requirements and eigenvalue sensitivity evaluation.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: New Method For Testing The Dynamic Cutting Force Coefficients

contributor:
Tlusty, J.
Mechanical Engineering

abstract:
 The dynamic behaviour of metal cutting process is investigated by measuring the Dynamic Cutting Force Coefficients. Measurements of eight components of the DCFC's are needed to describe completely the dynamics of metal cutting. This requires complex test apparatus and procedures, yet the experimental results are not very convincing.

 Investigations of the DCFC's for the inner modulation only, as recommended by Tlusty on CIRP in 1978, simplified the problem.

 A new method has been developed for measuring the inner DCFC's. The new method is based on Kal's idea who compared transient vibrations of a test rig in the cut with that outside the cut, which provides a direct assessment of the damping in the cutting process. New arrangements of the test and especially, the controlability of the damping of the rig itself leads to a qualitatively new situation permitting a high level of sensitivity and distinction of slight variations in the damping of the cutting process.

 The experimental results obtained by the new method are very convincing and are in a very good agreement with the general practical observations.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Making your own way: A grounded theory study of how  parents of children with autism navigate intervention

contributor:
McKibbon, K. Ann
Health Research Methodology

subject:
autism
caregivers
information use
knowledge translation
grounded theory
qualitative research
health services research
system navigation
patient engagement
patient-centred care

abstract:
Parents of children with autism shoulder substantial responsibility for navigating intervention to address autism-related concerns, and face conditions of high uncertainty and stress to do so. There is a lack of holistic research explaining how parents cope and respond to the complexity and obstacles that characterize their situation as they navigate multiple forms of intervention across multiple systems of care.
The purpose of this qualitative study was to develop a social psychological explanation in the form of a substantive theory of how Ontario parents of children with autism navigate intervention under complex informational conditions.
I used grounded theory methods, a constructivist approach and symbolic interactionist analytic framework for this research. The findings are primarily based on 45 in-depth (90-minute) interviews with 32 mothers from different urban and rural Ontario regions (fathers participated in 3 cases), and 9 professionals with expertise supporting parents. Documents were also analyzed. The central process of navigating intervention, labeled making your own way, consists of adjusting to the need to navigate intervention, in which parents construct the meanings that prepare and motivate them for taking action to navigate intervention. Adjusting consists of 4 interdependent sub-processes that together explain parents’ action: defining concerns, informing the self, seeing what is involved, and emotionally adapting. I portray the central process according to three overlapping heuristic stages: beginning the autism journey, handling transitions, and easing off. Many parents develop a strong sense of urgency to which they can respond by going into high gear, expending substantial personal resources sometimes at unsustainable rates in the pursuit of intervention.
The findings have implications for supporting parents to improve outcomes including parent stress. The central process of making your own way is generically transferrable to other healthcare consumer populations. Other conceptual elements have theoretical relevance for consumer-centered areas of health research.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Parents of children with autism shoulder significant responsibility for navigating many varying services and treatments (intervention) to address autism-related concerns, and experience great uncertainty and stress as they do so. There is a lack of research explaining how these parents respond to the complexity and obstacles they encounter as they navigate intervention. Using qualitative research methods, I interviewed 32 urban and rural Ontario parents (mostly mothers) and 9 professionals with expertise supporting parents to understand in detail how parents respond to their situation by making their own way to intervention. The resulting analytic findings have implications for improving support for parents of children with autism to reduce stress in their lives and improve other outcomes. The theory developed is also relevant for understanding how other healthcare consumer populations navigate intervention, and contributes to general knowledge in different consumer-centered areas of health research.


title: Embrittlement of CU-17Al Alloy By Liquid Mercury

contributor:
Ives, M.B.
Embury, J.D.

subject: embrittlement, alloy, liquid, mercury, cracks, boundary, stress

abstract: The role of plastic deformation in the initiation and propagation of cracks in Cu-17Al alloy embrittled by liquid mercury has been studied. It is proposed that extensive plastic deformation and work hardening must occur at the crack-tip during propagation in order to raise the local flow stress to a critical level at which the maximum normal stress is equal to the cohesive strength. A crack initiation mechanism is proposed involving grain boundary diffusion enhanced by the stress concentration at the head of dislocation pile-ups at the grain boundary. Micro-cracks are formed at the weakened grain boundary and a period of stable crack growth made over a period of increasing applied stress may be necessary before the crack is long enough to become unstable.

abstract: Thesis

abstract: Master of Science (MSc)


title: The effect of resistance training repetition load on muscular hypertrophy and strength in young resistance trained men

contributor:
Phillips, Stuart M
Kinesiology

subject:
Resistance exercise
Hypertrophy
Strength
Young men

abstract: Resistance training (RT)-induced skeletal muscle hypertrophy is partly responsible for the RT-induced increase in strength. Previously, we reported that exercise repetition load played a minimal role in the promotion of RT-induced gains in hypertrophy and strength gains in RT-naïve participants performing RE to volitional failure. Thus, the main aim of this study were to determine the effects of 12 weeks of RT on muscle strength and hypertrophy in a trained population. 49 resistance-trained men (mean ± SEM, 23 ± 1 years, 85.9 ± 2.2 kg, 181 ± 1 cm) were randomly allocated into a lower load-high-repetition group (HR, n=24) or a higher load-low-repetition group (LR, n=25). Repetition load was set so that volitional lifting failure was achieved within the repetition ranges of 20-25 (~35-50% of 1RM) for HR or 8-12 for LR (~70-85% of 1RM). Strength as one repetition maximum (1RM) was assessed pre and post.  Changes in lean body mass (LBM), appendicular lean mass (ALM) and leg lean mass (LLM) were assessed using dual-energy x-ray absorptiometry (DXA). There were significant increases in strength in all exercises with no differences between groups (p > 0.05) with the exception of bench press where LR showed a greater increase in 1RM than HR (p = 0.012).  Similarly, LBM, ALM, and LLM increased significantly following training in the HR group (1.0 ± 0.9kg, p < .001; 0.8 ± 1.1 kg, p < 0.05; 0.7 ± 0.9 kg, p < 0.01 respectively) and the LR group (1.6 ± 1.4 kg, p < .001; 1.0 ± 1.2 kg, p < 0.05; 0.7 ± 1.0 kg, p < 0.01 respectively) with no significant differences between groups (all p > 0.05). These data show that RE performed to volitional failure using either HR or LR induces similar adaptations strength and lean mass accrual in young resistance-trained men.

abstract: Thesis

abstract: Master of Science in Kinesiology

abstract: Resistance training (RT) results in an increase in muscle growth and an increase in strength. Previously, we have shown in young untrained males, that when exercise is performed until failure, or until the weight can no longer be lifted, that gains in muscle and strength were similar with the use of either light or heavy weights. The purpose of the study was to determine the effects of 12 weeks of RT on muscle growth and strength in young men who were already regularly participating in resistance exercise when performing either lower load high repetition RT (HR) or higher load low repetition RT (LR). Maximum strength and changes in muscle mass were assessed prior to and upon completion of the training protocol. Following 12 weeks of RT both groups increased muscle mass and strength to a similar extent with the exception of bench press which increased more in the LR group.


title: A LONGITUDINAL INVESTIGATION OF CIRCADIAN RHYTHMS AND SLEEP DISTURBANCES ACROSS THE PERINATAL PERIOD IN WOMEN AT LOW AND HIGH RISK OF POSTPARTUM DEPRESSION

contributor:
Frey, Benicio
Neuroscience

subject:
Circadian Rhythms
Mood
Sleep
Perinatal

abstract: Postpartum depression (PPD) remains a serious mood disorder without a known etiology. PPD has a prevalence of 7-15% in the general population. Women with a history of a mood disorder are at an even higher risk for the development of PPD. Work over the last few decades has established a strong association between circadian rhythm and sleep disturbances and mood disorders, such as Major Depressive Disorder (MDD) and Bipolar Disorder (BD). Despite the breadth of evidence associating circadian rhythm disruption and depressive mood episodes, literature establishing a connection between circadian rhythms and changes in mood across the perinatal period is lacking. The work outlined in this thesis aimed to address this gap by examining the association between circadian rhythm and sleep disturbances across the perinatal period and their association with changes in mood in women at high and low risk of PPD development. A total of 87 women were studied, 45 healthy controls and 42 women with a mood history. Women were interviewed during the third trimester of pregnancy and between six to twelve weeks postpartum. Sleep and circadian rhythms were measured using both subjectively with self-reported questionnaires and objectively with actigraphy. Our results show that women at high and low risk showed higher disruption differ in subjective circadian rhythmicity, as well as in both subjective and objective parameters of sleep. Specifically, women at high risk for postpartum were found to have lower sleep efficiency, as measured by actigraphy, in the postpartum. In addition, subjective and objective parameters of sleep and circadian rhythms are associated with changes in depressive symptoms across the perinatal period. Our findings suggest that stabilizing circadian rhythms and improving sleep quality throughout the perinatal period can prevent postpartum mood worsening, particularly for those women at greatest risk.

abstract: Thesis

abstract: Master of Science (MSc)


title: Geochemistry of Tungsten

contributor:
Shaw, Denis M.
Geology

subject: colorimetric, tungsten, geochemistry, silicate, rocks

abstract:
 Chan and Riley (1967) developed a colorimetric method for
the determination of tungsten in natural waters and silicate rocks.
Applied to silicate rocks this method contains the following stages:
evaporation of silica with hydrofluoric acid, co-precipitation of
tungsten and some other elements, with hydrous manganese dioxide and cation-exchange separation of vanadium, molybdenum and tungsten. When applying this method on standard solutions and the new U.S.G.S. standard rocks, the results obtained are lower than those suggested by the authors. The results obtained recently with neutron activation analysis of the same standard rocks by Johansen and Steinnes (1970), although different from the results of the present work, also disagree with Chan and Riley. The method was abandoned since a tungsten loss is believed to occur throughout the procedure.

abstract: Thesis

abstract: Master of Science (MSc)


title: Determination of the Composition of Metamorphic Rocks By Use of The Point Counter

subject: rocks, micrometric analyses, point counter, bulk composition, metamorphic rocks, Sillimanite Garnet Gneiss, Quartz

abstract: A short history of micrometric analyses of rocks; the use of the point counter to determine the effect of orientation on the bulk composition of metamorphic rocks, the variations and limitations of the method with comparison of calculated analyses from the modes with an ordinary chemical analysis. The discrepancies lie within the range of experimental error. A quantitative interpretation by the use of statistics is offered.

abstract: Thesis

abstract: Master of Science (MSc)


title: Power Spectral Analysis of a Forcemain Failure Caused By Waterhammer

contributor:
James, William
Civil Engineering

subject: failure, forcemain, waterhammer, pressure, pipe, wave, power

abstract:
 The failure of the Ancaster forcemain was thought to be related to waterhammer effects. The sequence of breakages of the main are reviewed. A series of pressure recordings were made on the forcemain, leading up to and including collapse. The recordings comprise a unique data set.

 These pressure recordings were digitized and subjected to power spectral analysis. The power spectra pointed out several significant events that were not evident from the pressure record alone.

 These included the fact that the original break occurred in the forcemain several days prior to its ultimate collapse and discovery on the surface. It was also determined that the break in the pipe was due to the apparent merging of the primary waterhammer wave with an existing but gradually changing lower frequency wave. This second wave was associated with rigid column motion and gradually increased its frequency. The resultant wave carried sufficient energy to cause the ultimate failure of the evidently already damaged forcemain.

 Power spectral analysis proved useful as a method for analysing waterhammer effects in a forcemain complicated by column separation, leakage and vapour pocket collapse. and may be a useful way of monitoring the performance of longer pipelines.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: A Bench Scale Comparison of Batch and Continuous Settling

contributor:
Murphy, K.L.
Chemical Engineering

subject: bench, scale, comparison, batch, settling

abstract:
 A bench scale continuous settling unit was constructed and its operation compared to results of batch settling tests. The particulate solids used were polystyrene spheres with a mean diameter of 285 microns. The concentration profile within the slurry in both the batch and the continuous studies was observed using a light extinction technique.

 The results show that for the material used in this study, the solids flux limitation of the continuous settler could not be exceeded: the limiting condition in the operation was always the clarification capacity or upward velocity. The batch flux plot shows that this will be the case for any material which exhibits a flux plot that is essentially a single concave curve downwards.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: The Effects of Hay and Straw Mulches on Soil Temperatures and Moisture Values

title: The Effects of Hay and Straw Mulches on Soil Microclimates

contributor:
Hannell, F. G.
Davies, J. A.
Geography

subject: soil temperature, soil moisture, mulches, hay, straw, mulch diameter, seasonal changes, soil climate

abstract: Measurements of soil temperature and soil moisture values beneath and in close proximity to circular mulches of hay and straw were made. The experiments were conducted to determine whether sub-surface effects vary with mulch diameter, and to acquire information concerning the seasonal changes in such effects produced by a mulch of most favourable diameter. The modification of soil climate increased with a greater mulch size. A circular mulch with a diameter of 60 cms or less was considered to be of no practical value for winter protection of roots. The mulch with a 240 cms. diameter, provided some winter protection, preventing freezing of the soil, and, in summer caused considerable modification of the sub-surface climate. In the summer, soil temperatures were lowered by values of up to 5°C and 2.5°C at 5 and 100 cms. depth respectively. After a two-month period of dry weather, moisture values at 0-10 cms. depth beneath the mulch were 20% by volume, whereas, outside the mulch they were 5%. These differences decreased with increasing depth but were over 10% at 100 ems.

abstract: Thesis

abstract: Master of Science (MSc)


title: Spectral Analysis of Atmospheric Pollutants in the Upper Great Lakes Region

contributor:
Grundy, H.D.
Chemistry

subject: atmospheric, precipitation, great lakes, region, spectral, pollutants, cycles

abstract:
 Chemical data from atmospheric precipitation in the Upper Great Lakes region were collected on a monthly basis by various organizations from late 1972 to late 1975. The data for pairs of chemical parameters are regarded as simultaneously recorded time series and are analyzed by spectral analysis to bring out periodic components present in both time series and also to reflect the correlation and phase difference between the pairs of time series.

 The precipitation data have four major bands of periodicities: (1) a yearly cycle representing high and low atmospheric loadings in the summer and winter respectively with regards to Fe, PART, SO4 and P; (2) a 6 monthly period reflecting the four seasons of the year and affecting Fe, PART, P and pH; (3) a 9 monthly period for the heavy metals (Cu, Ni, Cd, Pb and Zn); and (4) 2 to 5 cycles/month periodicities caused by atmospheric turbulence and affecting all the parameters.

 The mining-smelting industry at Sudbury has been identified as a major point source of atmospheric emissions of acid, sulfate and the heavy metals, with the exception of iron, This is evident in view of the facts that the spectral intensities at the major periodicities decrease away from the mining-smelting centre; the strikingly high correlation and practically inphase relationship between Cu and Ni, and the 9 monthly period for the heavy metals which is associated with the industry.

abstract: Thesis

abstract: Bachelor of Science (BSc)


title: Many Body Effects in the Electron Gas And Position Annihilation

title: Many Body Effects

contributor:
Carbotte, J. P.
Physics

subject: Green's function, electron gas, metallic densities, annihilation, positron, Fermi momentum, field-theoretic,

abstract:
  A number of questions are examined concerning many body correlations in connection with electron gas at metallic densities (2 < = rs <= 5.7) and the annihilation of a positron in simple metals, by means of a technique involving the two particle correlation Green's function. Estimates are made of low temperature contributions to angular correlation data, which describe the momentum distribution of annihilating electron positron pairs, in the form of smearing at the sharp cutoff corresponding to the Fermi momentum from electron- and positron- photon interactions, and in the form of broad tails beyond the cutoff resulting from the high-momentum components introduced into the electron wave function by the presence of a periodic crystal lattice.

 Phonon effects are introduced into the perturbation expansion of the two particle Green's function describing an electron positron pair. A calculation of the lowest order phonon contribution seems to indicate that such effects do not explain the smearing at the Fermi momentum.

 A Green's function calculation of the first-order enhancement of the lattice tails, due to the positron-electron correlation, is made by introducing particle-lattice interactions explicitly in a model based on a simple metal such as sodium. It considers a weak potential and treats as zero the lattice components corresponding to other than nearest-neighbours points in reciprocal lattice space. The enhancement for rs =4, which is almost a constant, is
very similar to that for the main part of angular correlation data. This indicates that, for simple metals at least, angular correlation data can be interpreted directly from a free-particle model.

 Short-range correlations among opposite-spin electrons are examined by field-theoretic techniques as a step to obtaining a fundamental understanding of the correlations among electrons at metallic densities. A calculation of the
p.d.f. for opposite-spin electrons is positive over a wide range of metallic densities and seems to account for short-range correlations of the Coulomb hole through the multiple scattering of particle-particle ladders.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Political Economy Analysis of the Women's Community Cooperative in Hamilton, Ontario

contributor:
Chouinard, Vera
Geography

subject: cooperative, housing, political, economy, women, community, social

abstract:
 This research paper studies the urban phenomena of
cooperative housing in Canada. A political economy approach is used in this documentation of the delivery of the Women's Community Cooperative in Hamilton, Ontario. The focus of this paper is upon the individual members of the Innovative Housing Group, and how their collective actions enabled them to deliver this unique housing service. Individual members of the delivery group were studied to determine how political circumstances influenced their decision to create the Innovative Housing Group. They were also studied to determine what characteristics of their collective group enabled them to deliver the cooperative. Present day members of the cooperative were studied to determine how they view cooperative living and to see if involvement and participation was occurring within the cooperative organization. This study is relevant to urban geography as it shows how individuals may take control over their environment and with collective action overcome strong political, social, and economic forces to produce alternative housing types such as cooperatives.

abstract: Thesis

abstract: Candidate in Philosophy


title: COMPREHENDING CHINA’S STANCE TOWARD GLOBAL FINANCIAL GOVERNANCE: A TWO-STAGE MODEL

contributor:
O'BRIEN, ROBERT
Political Science

subject:
GLOBAL FINANCIAL GOVERNANCE
CHINA
FOREIGN POLICY
GLOBAL POLITICAL ECONOMY

abstract:
China’s attitude and foreign policies in global financial governance are not consistent. A two-stage model, which is comprised of formation of Guojia Liyi (interests and preferences of China, 国家利益) (Stage I) and decision-making process (Stage II), is
established to explain China’s policy inconsistency in global financial governance. Through this model, the thesis makes two major explanations for policy inconsistency. First, China’s Guojia Liyi in various global financial governance institutions and/or events may be different. These different Guojia Liyi are constituted by personal epistemic interests, interests of the state and national interests and are constrained by both material and ideational factors, particularly the domestic and international political economic environment, state ideology and interpretation. Therefore, China’s policies based on these Guojia Liyi vary. Second, even if the Guojia Liyi formed are the same in different events or institutions, the final actions are not always in accordance to the Guojia Liyi due to the influence of some factors on the specific decision-making process, such as lobbying, institutional conflicts and others. The two-stage model explains the policy inconsistency through both ontological and epistemological integration. Ontologically, this model considers structure and agent and treats both state and decision- makers as units of analysis. Epistemologically, this model incorporates both rational and cognitive school of thoughts by separating Guojia Liyi formation with specific decision- making processes and considering time as a crucial variable.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Multiple Forms of Dihydrofolate Reductase in Cultured Mammalian Cells

contributor:
Hillcoat, B.L.
Biochemistry

subject: dihydrofolate, reductase, cultured, mammalian, cells, enzyme

abstract: Dihydrofolate reductase from a subline of the L1210 lymphoma was purified by affinity chromatography using substituted Sepharose -4B to which was coupled methotrexate, a specific, tight binding inhibitor of the enzyme. The purified enzyme was subjected to disc gel electrophoresis at pH 8.5. At least two bands of activity were detected on the gel by the formation of a reduced formazan. Their ratios were dependent on enzyme concentration. Similar bands were found in the presence of EDTA (10^-6M), 4M and SM urea. When a substrate, NADPH (5xl0^-5M), was added to the buffers used in electrophoresis, three bands of enzyme activity were present in a fixed ratio which was independent of enzyme concentration. Protein bands showed a different but constant ratio. When folate replaced dihydrofolate as substrate in the assay mixture, the bands of activity corresponded at high concentrations of the enzyme. When activity was detected in the presence of an increasing concentration of methotrexate, different inhibition of the bands resulted. Preliminary experiments with crude extracts of the same subline gave activity profiles with multiple peaks.

abstract: Thesis

abstract: Master of Science (MSc)


title: Implementation of a Cellular Computing Memory Array

contributor:
Della Torre, E.
Electrical Engineering

subject: cellular, computing, memory, array, logic

abstract: A Cellular Computing Memory Array consisting of twenty cells of three words plus logic per cell has been constructed and interfaced to a digital computer. Both arithmetic and logic operations can be performed between words of a cell and those of adjacent cells, the results of which may be stored in any of the three words of the cell. The cells are organized in a two dimensional array so that each cell can communicate with the four nearest neighbours. In addition to the ordinary communication between cells to perform operations on data in adjacent cells, data can be transferred in the memory plane on a mass basis.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Ramsey Numbers

contributor:
Sabidussi, G.O.
Mathematics

subject: ramsey, numbers, asymptotic, finite, theoretical

abstract: This thesis gives new finite and asymptotic estimates of the Ramsey numbers using certain number-theoretical considerations; it also contains a brief historical survey on determination of Ramsey numbers and related number-theoretical problems.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Commuting Patterns of Union Park, Hamilton, From 1921 to 1931

contributor:
Harris, R.
Geography

subject: industrial, suburbanization, commuting, patterns

abstract: There is little information on the relationship between industrial decentralization and the suburbanization of blue collar workers in North American cities during the early twentieth century. The purpose of this research paper is to address the question of whether or not blue collar suburbanization preceded industrial decentralization in Hamilton, Ontario. This is done by examining the commuting patterns of an early twentieth century blue collar suburb known as Union Park, located in Hamilton Ontario. The research concludes that blue collar suburbanization preceded industrial decentralization in Hamilton. These findings imply that the frequency of this relationship requires further consideration.

abstract: Thesis

abstract: Candidate in Philosophy


title: Territoriality: A Fundamental Consideration of Spatial Behaviour

contributor:
Betak, J.F.
Geography

subject: territoriality, spatial, behaviour, delineation, field theory

abstract:
 The central theme of this paper is territoriality. Essentially, I am concerned with the part that territoriality plays in determining spatial behaviour. Part One introduces the subject and demonstrates the need for geographers to examine territoriality more thoroughly. The newly developed field of behavioural geography is assessed, the importance of scale being a fundamental consideration. Part Two deals with definition of territoriality in animal
and human populations. The problems encountered in definition and delineation of human territories are discussed. Part Three poses two important questions. 1. What function does territoriality serve? 2. Is territory innate or a cultural acquisition? Although the answers to these questions are subject to further research, the importance of these considerations is demonstrated. Part Four considers dominance and leadership. The spatial implications of these concepts are developed. Part Five centres about territorial encroachment and the subsequent reaction. Essentially territorial encroachment (or intrusion) is conceived as a violation of regular spacing patterns. Possible reactions to encroachment are considered. Part Six deals with typology. Two levels of study are distinguished those being Micro territories (personal space) and macro territories (larger units of territory). These two concepts are differentiated by scale. Studies conducted at each of these levels are discussed. Part Seven puts forth a hypothetical construct which integrates the work of several researchers. The "interaction distance" equation is a model which, hopefully, assists the researcher in understanding and possibly predicting the space maintained between interactants. Briefly, the model consists of the subject, the object and the situation. These components determine the interaction distance. Although quantification of the components is not included in this paper, problems in calibration are considered. The utility of the model is also discussed. Part Eight applies a methodological construct, of field theory, to spatial behaviour. The essential concepts of field theory, (the life space, boundary zones, and space of free movement), are discussed in a conceptual and physical sense. Finally, the life space concept is conceived as a territorial range or orbit in which the spatial behaviour of the individual is conducted. In fact, the field theory might greatly assist geographers in understanding and predicting spatial behaviour.

abstract: Thesis

abstract: Bachelor of Arts (BA)


title: Soft Photon Theorems in Bremsstrahlung and Photoproduction of Pions

contributor:
Nogami, Y.
Physics

subject: photon, bremsstrahlung, cross-section, photoproduction, pion, theorem

abstract: In the soft photon limit the bremsstrahlung cross-section is related to the corresponding elastic scattering cross-section in a model-independent manner. The cross-section for threshold photoproduction of pions becomes independent of the detailed pion-nucleon interaction if the ratio of pion to nucleon mass is made sufficiently small. These two results are a consequence of the gauge invariance of the scattering amplitude for a process involving one photon. We review the derivation of Low's bremsstrahlung theorem for spin-zero and spin-half particles, and outline an extension to all orders of photon energy. The theorem for photopion production is derived by the same method. A non-relativistic analogue to the Bremsstrahlung theorem is also considered.

abstract: Thesis

abstract: Master of Science (MSc)


title: THE IN VIVO RESPONSE OF KNEE ARTICULAR CARTILAGE TO RUNNING AND BICYCLING

contributor:
Maly, Monica R.
Health Sciences

subject:
T2 Relaxation
Magnetic Resonance Imaging
Knee
MRI
Osteoarthritis
Running
Bicycling
Physical Activity
Cartilage

abstract:
Background
Knee osteoarthritis is a degenerative joint disease characterized by damaged cartilage, tendons, ligaments, synovium, and bone. Knee osteoarthritis causes joint pain, reduced joint function, and decreased quality of life and is the leading cause of chronic disability in older adults. Two of the major risk factors for knee osteoarthritis are increasing age and obesity. To decrease the occurrence of knee osteoarthritis in our aging population, it is important that we identify exercises that are safe for people with or at risk of knee osteoarthritis.
Purpose
The main purpose of this thesis was to compare the acute response of knee cartilage composition to two common aerobic activities, running and bicycling, of equal total load. To address the primary purpose, we first sought to determine the reliability and validity of measuring loading repetition during running (steps) and bicycling (pedal-revolutions) using accelerometry.
Methods
1) Twenty-two healthy adults completed running and bicycling activity bouts (five-minutes) while wearing six accelerometers: two at each the waist, thigh and shank. Accelerometer and video data were collected during each activity. 2) Fifteen healthy men completed running and bicycling activities of equal cumulative load that were preceded and followed by a series of magnetic resonance images.
Results
1) Excellent reliability (ICC≥.99; SEM≤1.0) and validity (Pearson≥.99) were found for step and pedal revolution measurements taken by an accelerometer placed at the shank. 2) Bicycling did not cause significant changes in cartilage composition (p=0.274); however, running did cause a change in cartilage composition (p=0.002).
Conclusion
Findings from this thesis suggest that to acquire reliable and valid step and pedal revolution measurement, accelerometers should be placed on the shank. Furthermore, bicycling causes no statistical changes in knee cartilage, while running does. Bicycling may therefore be used to combat obesity and maintain cardiovascular health in individuals with compromised joint health.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Knee osteoarthritis is a degenerative joint disease that affects all knee tissues, particularly articular cartilage.  This “wear and tear” condition reduces mobility and creates pain, collectively decreasing quality of life. Two important risk factors for knee osteoarthritis are age and obesity. While we cannot stop aging, exercise can have a positive impact on weight, particularly among adults with knee osteoarthritis. This thesis provides foundational information on how running and bicycling affects knee cartilage. First, we identified a useful method of measuring steps during running and pedal revolutions during bicycling. Second, we compared the effect of running and bicycling of equal cumulative load on knee cartilage, using MRI.  The running activity was 1/3 the length of the bicycling activity but despite shorter exposure, running caused changes in cartilage shape and composition, while bicycling did not. These findings suggest that bicycling is a suitable aerobic activity that reduces loading at the knee.


title: Development of an Optofluidic Platform Based on Total Internal Reflection- Application of Dissolved Oxygen Sensing for Water Monitoring

contributor:
Fang, Qiyin
Biomedical Engineering

abstract:
Water quality is of great importance to human as well as other forms of lives. The concentration of dissolved oxygen (DO) is one of the essential indicators for water quality. DO sensing has been widely used in many environmental applications such as natural water monitoring and waste water treatment. Three methods are currently used for DO measurement, namely titration, electrochemical and optical. In the optical method, DO is quantified by the reduction of fluorescence emission intensity of Ru based fluorophores through fluorescence quenching process. This optical method is compatible with
autonomous DO monitoring while the titration method is not, and it has the advantages of faster response and higher sensitivity than the electrochemical method. These properties make the optical method suitable for surveillance of water quality over time as well as near real-time and high sensitivity detection of contaminations. In this thesis, we report the design, simulation, fabrication and characterization of a fluorescence quenching based DO sensing optofluidic device with the focus on sensitivity enhancement and cost/size reduction. In our method, DO detection sensitivity was improved by 4 folds through employing total-internal-reflection of the excitation light and optimizing the fluorophore film thickness in a multilayered microfluidic sensor structure. System cost and size were also reduced in this design.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Solvent Extraction by a Rising Slug

contributor:
Baird, M.H.I.
Chemical Engineering

subject: slug, solvent, extraction, organic, mass

abstract: Several types of apparatus have been previously developed to give a constant and measurable interfacial area for solvent extraction. In this work, a new and relatively simple device for this purpose has been tested. The organic phase is allowed to rise or fall freely through the aqueous phase in a tube as a cylindrical "slug". In the mass transfer operation, the "slug" of sparingly-soluble organic liquid is held stationary by the downflow of water. The shrinkage rate of the slug can be measured easily and it gives the experimental mass transfer rate. In order to apply the Higbie penetration theory to the experimental conditions, the interfacial velocity and radius ratio of the slug must be known; these factors can be calculated from the hydrodynamics of the system, using the measured value of slug superficial velocity. Finally, a comparison between experimental and theoretical mass transfer results can be made. 1-butanol shows a good agreement (to within 1%) while 1-pentanol and methyl iso-butyl ketone show less satisfactory agreement due to lack of precise data on their molecular diffusivities in water.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: On the Concept of Electric Taxiing for Midsize Commercial Aircraft: A Power System and Architecture Investigation

contributor:
Emadi, Ali
Mechanical Engineering

subject:
Electric Taxiing
Green Taxiing
Green Taxi
Powertrain Design
Electric Taxiing System (ETS)
System Sizing
More Electric Aircraft
Simulation
Model-Based Design
Aircraft Taxiing Drive Cycles
Kinematic Analysis
Requirements Analysis
Regenerative Braking
Power Electronics
Motor Controls
Inverter
Switch Loss Model
Efficiency Map

abstract: This research introduces a high-performance electric taxiing system (ETS) as a modern solution to improve the on-ground operations of today’s aircraft, which are conventionally powered through the main engines. The presented ETS is propelled by electric motors, integrated into the main landing gear of a state-of-the-art midsize commercial aircraft, and powered by an additional not quantified electrical energy storage system. The proposed system can therefore operate autonomously from any aircraft-internal power source, i.e. Auxiliary Power Unit or equivalent. The main objective of this work is to assess the energy consumption of the introduced ETS while considering energy recuperation due to regenerative braking. The ETS powertrain is sized to match modern conventional taxi performances that were seen in 36 self-recorded takeoff- and landing taxi driving profiles. A custom ETS simulation model was developed and simulated across all available driving profiles to confirm the desired powertrain performance and to predict the system’s energy consumption. For the purpose of enhancing the validity of these energy consumption predictions, a suitable motor controller is then designed by the use of MATLAB Simulink. An easy-to-implement switch loss model was created to predict the ETS motor controller efficiency map. Finally, the former energy consumption predictions were revised for the implementation of the motor controller and an estimated traction motor efficiency map. The results exhibit that the revised ETS simulation model was capable of refining the energy consumption. It was found that the ETS will consume up to 9.89 kWh on average if the full potential of the traction motors energy recuperation capabilities are being used. The simulation outcomes further demonstrate that regenerative braking offers great potential in ETS applications since more than 14 % of required traction energy could be regenerated to yield the above mentioned average energy consumption.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: The Importance of Electric Motor Thermal Management and the Role of Polymer Composites in Axial Cooling

subject:
Electric Motor
Cooling
Thermal Management
Conductive Polymer
Thermal Modelling
Composite

abstract:
The following research investigates the effect that axial cooling channels will have on the performance of the thermal management system of a hypothetical switched reluctance motor. A baseline motor with no axial cooling will be compared to an identical motor with the innovative cooling design implemented. This will allow for a direct comparison of the two designs, with a quantifiable performance increase determined through thermal simulations.
The ability of a polymer composite to transfer heat to the axial cooling channel is also explored. A detailed material selection process is discussed with the result being an epoxy polymer composite. The material development of a thermally enhanced polymer composite is then investigated to achieve a maximum thermal conductivity material that can exist within the stator slot to achieve enhanced thermal energy transfer.

abstract: Thesis

abstract: Master of Applied Science (MASc)

abstract: The desire to increase the power density of electric machines is becoming an increasingly popular challenge, especially in the automotive industry. With the advent of electrified powertrains as an alternative solution to conventional internal combustion powered vehicles, the topic of increasing electric motor performance is becoming very attractive area of research. An important aspect of electric motor performance is the way in which the generated thermal energy is managed. Through material development and innovative motor design, there exists the opportunity to cool electric motors through cooling paths flowing axially through the stator. This ‘axial cooling’ design has the opportunity to greatly increase motor cooling by removing thermal energy directly from its main source, the motor windings. The following research is aimed at the thermal design of the axial cooling and the role in which thermally conductive polymer composites play in order to enhance motor cooling.