title: “HOW CAN WE SHARE WHEN WE DON’T GO OUT?” PSYCHOSOCIAL SUPPORT GROUPS FOR NORTH INDIAN WOMEN

contributor:
Schwartz, Lisa
Nouvet, Elysée
Global Health

subject:
mental health
depression
women's health
community mental health
India
ethnography
qualitative research
gender inequality

abstract:
Background: Although major depression is one of the leading causes of premature death and
disability in India, there is little infrastructure to provide mental health services in the rural North
Indian state of Uttarakhand. The worldwide burden of depression is 50% higher in women than
men, however Indian women experience the double burden of gender disadvantage and poverty
which restricts their autonomy and access to social support, and increases their risk for common
mental disorders (CMDs). In this low resource setting, community mental health (CMH) models
of care may offer the best approach to supporting women with CMDs.

Objective: This study partnered with a local NGO in Uttarakhand to examine the factors
influencing women’s participation in psychosocial support groups (PSSGs), and the groups’
impact on the women and their communities. PSSGs had been set up in the communities for a
minimum of 6 months.

Methodology: Focused ethnographic research was conducted over three months in 2016,
involving ten focus group discussions (FGDs) with seven unique PSSGs, representing a total of
43 women. FGDs were conducted with PSSGs that had been active a minimum of 6 months.
They included both persons with psychosocial disability and their caregivers, primarily divided
into separate PSSGs. FGDs were conducted across three different sites, with predominantly
Muslim and Hindu populations. Additionally, eight key informant interviews were conducted
with community health workers and mental health professionals. Data was translated and
transcribed from Hindi to English.

Results: The principal barrier to PSSG participation was gender inequality, more specifically,
women not being granted permission to leave the home to participate. In terms of impact, the
women explained how learning and talking about their own depression and anxiety increased
their knowledge and improved their mental health. PSSGs created safe social spaces for women
to talk, which increased women’s confidence to speak freely in their community. As a result of
the PSSGs, women felt that they had reimagined their roles as community members, shifting
from the role of receiver of help to provider. Communities were impacted by the PSSGs as
women shared their mental health (MH) knowledge widely, and referred and accompanied
community members to MH services.

Discussion: These findings are significant because women in PSSGs were able to work together
to improve their MH in the context of high gender inequality and mental health stigma. Greater
ability to speak out and act collectively may empower women to contribute to household and
community decisions, and participate economically, advancing their health and social interests.
This research demonstrates how PSSGs can benefit not only the women involved but their
community and its mental health. It highlights the importance of understanding models for CMH
services that build on local resources and can serve as a model for other underserved
communities.

abstract: Thesis

abstract: Master of Science (MSc)


title: Assessing Students' 'Readiness for Practice': Field Instructors' Experiences and Perspectives

contributor:
Baker Collins, Stephanie
Social Work

subject:
readiness for practice
field instruction
field placement
issues in placement
BSW students

abstract: This study aims to explore and understand the ways in which social work field instructors assess ‘readiness for practice’, particularly in situations where a BSW student has experienced a placement breakdown or failure. Through the examination of existing literature, themes of gatekeeping, assessments of readiness, field instructors’ relationships with the academic institutions and tensions between the worlds of social work values and gatekeeping emerged. Rooted in an interpretive methodology and supported by in-person interviews, the study sought the feedback and experiences of five BSW field instructors, with the intention of better understanding the ways in which field instructors assessed ‘readiness for practice’. Emphasizing the use of the term ‘readiness’, the findings suggest that assessing readiness for practice is a multi-layered process. They presented some similarities in the skills and values deemed essential for BSW students to possess to demonstrate readiness and discussed some of the problematic behaviours that contributed towards lack of readiness and placement breakdowns/failures. The findings also discussed the tension that field instructors experience in relation to their mentoring and gatekeeping roles and their desires to see an increase in the collaborative relationships with academic institutions.  This study encourages field instructors and Schools of Social Work to critically analyze and explore ways in which they can advance their relationship and work collectively to address issues pertaining to lack of readiness for practice.

abstract: Thesis

abstract: Master of Social Work (MSW)


title: Land for Conservation – Spencer Creek Conservation Authority Schemes and Land Acquisition

contributor:
Weaver, John
History

subject:
Conservation
Land Acquisition

abstract: The Conservation Authorities Act was passed by the Ontario Provincial legislature in 1946 to further the “conservation, restoration, development and development of natural resources other than gas, oil, coal and minerals.” On 8 May 1958, Ontario’s 25th conservation authority was established on the watershed of Spencer Creek near Hamilton. The Spencer Creek Conservation Authority (SCCA) recognized that in order to acquire the necessary lands for conservation it was in a race with developers and urban sprawl. An aggressive land acquisition programme was initiated by the SCCA (1958-1966) and continued by its successor, the Hamilton Region Conservation Authority.  The success of this programme from 1958-1971 created a green framework for the region, with many of our most popular and ecological important conservation areas acquired during this period, including: Dundas Valley, Christie Lake, Valens, Spencer Gorge, Beverly Swamp, and Summit Bog. However, acquisition of such a vast acreage of conservation land doesn't just happen by desire, it involves many operational factors. Available funding, administrative policies, land owner engagement, knowledge of the property market, and public and political support were all central aspects of this land acquisition program. This research paper examines these inter-related factors and outlines the many challenges and initiatives that led to the acquisition of over 3,300 acres of land for conservation.

abstract: Thesis

abstract: Master of Arts (MA)


title: Characterization of the glycosylation of newborn and adult alpha-2-macroglobulin

contributor: Medical Sciences (Blood and Cardiovascular)

subject: Alpha-2-macroglobulin

subject: Glycosylation

abstract:
Introduction: Alpha-2-macroglobulin (α2m) is a plasma glycoprotein serine protease inhibitor. Previous studies have shown that coagulation factor concentrations are highly variable with age and α2m levels have been found to be twice as high in newborns compared to adults. This may contribute to a resistance towards thrombotic events observed in young populations. Protein glycosylation is known to affect protein activity and the glycosylation profile of adult α2m has previously been analyzed. Information regarding glycosylation of α2m in other age groups has yet to be elucidated. Therefore, the purpose of this study is to examine the differences in the glycosylation profiles between newborn and adult α2m.
Methods: To evaluate glycan macroheterogeneity, plasma samples were enzymatically deglycosylated by PNGaseF, followed by SDS PAGE and western blotting (WB) to detect α2m. To evaluate microheterogeneity, plasma samples were incubated with Neuraminidase (Clostridium perfringens) followed by native PAGE and WB to determine sialic acid content. To detect non-sialylated terminal galactose residues, plasma samples were incubated with immobilized RCA120, and lectin-bound molecules were separated from unbound molecules. Additionally, the affinity of α2m for ricin was evaluated by eluting bound proteins with increasing concentrations of galactose. All fractions were subjected to SDS-PAGE and WB to detect α2m. 2D gel electrophoresis was completed to examine differences in pI and molecular weight of α2m in both age groups. Purification by immunoprecipitation was also performed and eluted α2m was analyzed by fluorescence-assisted carbohydrate electrophoresis (FACE) to determine the glycan fingerprint in the two populations.
Results:  Deglycosylation of both newborn and adult α2m with PNGaseF resulted in a change in migration and apparent molecular weight, however no statistically significant difference was found between newborn and adult. On native PAGE following treatment with neuraminidase, newborn α2m exhibited a statistically significant change in migration compared to adult. Additionally, newborn α2m exhibited a higher percentage of molecules bound to RCA120 than adult (no statistical difference) and elution of α2m from RCA120 with a galactose step gradient produced similar profiles for newborn and adult molecules. 2D electrophoresis and WB revealed a difference in pI of α2m in newborns as compared to adults. Finally, purified newborn and adult α2m were analyzed by FACE and quantification of prominent fluorescent bands revealed a higher secondary:primary band ratio in newborns when compared to adults.
Conclusions: To our knowledge, this is the first study investigating glycosylation differences between newborn and adult α2m molecules. The results from PNGaseF analyses indicate no significant difference in total N-glycan content. Neuraminidase results suggest significantly greater sialic acid presence on newborn α2m, however there was no significant difference in galactose content. 2D electrophoresis revealed a difference in pI as well as the way in which newborn and adult α2m degrade when exposed to experimental conditions. A2m was successfully purified from both newborn and adult plasma, and FACE results indicate that the proportion of more branched glycans present in the two major fluorescent bands are of higher quantity in newborns than adults.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Hurd, T.R.
Mathematics

abstract: Title: Conditional Value at Risk as a Criterion for Optimal Portfolio Selection, Author: Maria Betcheva, Location: Thode

abstract: The focus of my master's project involves research Conditional Value at Risk (or Expected Shortfall) as a risk measure for optimal portfolio selection. The project is organized as follows. In the first chapter, we introduce and discuss the quantile based risk measures, Vale at Risk (VaR) and Conditional Vale at Risk (CVaR), with respect to axiomatic characterization of coherent measure. The properties and advantages of CVaR are analyzed. The second chapter deals with mean-risk models of portfolio optimization. The common idea in all asset allocation models is the minimization of some measure of risk while simultaneously maximizing portfolio expected return. Portfolio optimization in a mean-CVaR framework has been actively discussed recently. CVaR is a numerically tractable measure, allowing optimal portfolios to be computed by means of covex programming. Most importantly for applications, however, a mean CVaR model can be used with scenario simulation of loss distributions. We investigate the convergence of the Monte-Carlo based CVaR optimal portfolio algorithm when an analytical solution of the optimization problem can be obtained. The last chapter considers the benchmark (or relative) portfolio selection problem in terms of a multiobjective problem. Tracking error optimization in a mean-multirisk framework allows implementation of an interactive decision making and taking into account of the investor's preferences.

abstract: Thesis

abstract: Master of Science (MS)


contributor:
Balakrishnan, Narayanaswamy
Statistics

abstract: Title: Inferential Methods for Bivariate Logistic Model, Author: Enayetur S.M. Raheem, Location: Thode

abstract:
There are several methods available for estimating the parameters of bivariate logistic
model. In this report, we compare the method of Maximum Likelihood (MLM),
weighted least squares cdf method (WLS), elemental percentile method (EPM) and
Castillo's least square method (CLS) for estimating the parameters λ, δ, σ, τ, of bivariate
logistic model. We perform Monte Carlo simulation to compare the MLM,
WLS and CLS on the basis of mean squared errors (MSE) and bias of the estimators
δ and τ by keeping λ = 0 and σ = 1 fixed. It has been found that no method is
uniformly better than the others, but MLM and CLS perform better than the others
in terms of MSE. We compared MLM and CLS on the basis of average confidence
lengths for δ and τ. It has been found that MLM produces shorter confidence intervals
than the CLS. In the CLS method, three different weights, β = 0.5, 0.9, 1, have
been considered and comparative results for this method are also presented.

We applied four methods of estimation to the UK pig production data (1967-
'78) as the bivariate logistic distribution has been found to be a good fit to this
data (Castillo, Sarabia and Hadi 1997). We compared all four methods on the basis
of MSE, bias and lengths of confidence intervals for the parameters λ, 𝛿, σ, τ using
bootstrap resampling technique. Again, MLM and CLS are found to be performing
better than the other two methods, which agrees with the results obtained using
Monte Carlo simulation.

CLS has been found to be advantageous than MLM for small sample size (e.g.,
n < 25) and especially when the scale parameters are very small.

abstract: Thesis

abstract: Master of Science (MS)


contributor:
Wilson, Margo
Daly, Martin
Psychology

abstract: Title: Age-Specific Birth Rates in Brazil: Economic and Social Predictors of Reproduction by Adolescent and Adult Women, Author: Sarah Goodwin, Location: Thode

abstract:
For those who have reason to doubt the certainty or quality of their futures, it may
be adaptive to engage in an accelerated life course and reproduce earlier than the public
health policy officials consider ideal. This hypothesis was examined using life
expectancy, school registration, income, income inequality, and the degree of
urbanization to predict the birth rates of 15-19 year olds across municipalities in Brazil.
To evaluate whether adolescents respond differently to these indicators than older
women, the results for 15-19 year olds were compared to those obtained for women 20-
29, 30-39, and 40-49 years old. Negative binomial regression results indicate that
although teenage women seem to be the most sensitive to these socioeconomic indicators,
older women adjust their reproductive efforts in a similar manner. More specifically,
higher birth rates in all age groups are found in municipalities with short life
expectancies, lower rates of school registration, lower average incomes, and higher
income inequality. The degree of urbanization predicts differential effects according to
age; for the 15-29 age group it is positively associated with birth rates and for the 30-49
year old women it is a negative predictor. Repeating the analyses within the five Major
Regions of Brazil yields directionally consistent relationships for all predictors compared
to those for the country as a whole.

abstract: Thesis

abstract: Master of Science (MS)


title: Statistical Inference for r-out-of-n F-system Based on Birnbaum-Saunders Distribution

contributor:
Balakrishnan, Narayanaswamy
Davies, Katherine
Statistics

subject:
r-out-of-n F-system
Statistical Inference
Birnbaum-Saunders Distribution
Maximum Likelihood Estimation

abstract:
The r-out-of-n F-system and load-sharing system are very common in industrial engineering. Statistical inference has been developed here for an equal-load sharing r-out-of-n F-system on Birnbaum-Sauders (BS) lifetime distribution. A simulation study is carried out with different parameter values and different censoring rates in order to examine the performance of the proposed estimation method. Moreover, to find maximum likelihood estimates numerically, three methods of finding initial values for the parameters - pseudo complete sample method, Type-II modified moment estimators of BS distribution method and stochastic approximation method - are developed. These three methods are then compared based on the number of iterations and simulation time. Two real data sets and one simulated data set are used for illustrative purposes. Finally, some concluding comments are made including possible
future directions for investigation.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Hurd, T.R.
Mathematics and Statistics

abstract: Title: The Impact of a Mean-Reverting Stochastic Differential Equation on Optimal Portfolio Allocation, Author: John McNair, Location: Thode

abstract:
We consider the dilemma an investor contemplates when faced with the decision to
allocate proportions of initial wealth within a multi-"risky" asset framework in order to
maximize terminal wealth. It is assumed that Geometric Brownian Motion generates the
"risky" asset price paths for this problem formulation. We consider the particular setting
where the "risky" assets exhibit dependence on an Arithmetic Ornstein-Uhlenbeck
stochastic differential equation (AOU) in the form of correlation and an embedded
adjustment to the stochastic drift. We exemplify the motivation for this problem
formulation by highlighting the empirical dependence that has occurred between the daily
returns 1 of the TSX Composite Index (S1), the daily returns of the Scotia Capital Overall
Bond Index (b1) and the Yield Ratio^2
(Rt). We then derive the optimal portfolio control
for this investor, using the Hamilton-Jacobi-Bellman equation method. We then
construct optimal portfolios using Mean-Variance-Optimization (MVO) and compare
terminal wealth for two investors using Monte-Carlo Simulation. Investor A is
incognizant of the above dependence whereas Investor B is cognizant. We vary the
above dependence parameters and assess the overall impact on the probability
distribution of terminal wealth

abstract: Thesis

abstract: Master of Science (MS)


title: Assessing the Relationship Between Depression and Obesity Using Structural Equation Modeling

contributor:
Akhtar-Danesh, Noori
Statistics

subject: depression, obesity, structural equation, modeling, mental health, gender, socioeconomic

abstract:
 In this project we used structural equation modeling to analyze the data collected
for the Canadian Community Health Survey (CCHS) Cycle 1.2 - Mental Health and
Well-Being conducted by Statistics Canada. The data are cross-sectional.

 We looked at the relation between depression and obesity adjusting for gender, socioeconomic status, gene-environment interactions, eating and physical activity and stress.

 We used the AMOS and Mplus softwares to analyze our data. The first one used continuous variables for depression ("persistence of depression", in years) and obesity ("body mass index"-BMI), while the second used categorical variables: lifetime depression, 12 month depression and obesity (normal weight, overweight and obese). We also used two variables to measure different aspects of stress: self-perceived ability to handle an unexpected problem and work stress-social support.

 We fitted the models across the entire data, but also across different groups: males versus females and groups based on gender and BMI.

 The results indicated that the relationship between depression and obesity is different across gender.

 The limitations of the study are also discussed.

abstract: Thesis

abstract: Master of Science (MSc)


title: Listener vs. Speaker-Oriented Speech: Studying the Speech of Individuals with Autism

contributor:
Humphreys, Karin R.
Psychology

subject: listener, speaker,speech, oriented, language, pragmatics, disfluencies, word order

abstract:
 Listener vs. speaker-oriented speech: Studying the language of individuals with autism
There are many mechanisms speakers utilize in conversation that aid a listener's understanding. However, there are also many characteristics of speech where it is unclear
whether they serve listener or speaker-oriented functions. For example, speakers
frequently produce disfluencies such as "um or "uh," which are helpful to listeners,
indicating that the speaker is not finished speaking yet. We do not know, however, if
these are used intentionally to aid listeners. In addition, the tendency to place animate
items as sentential subjects may benefit either speaker or listener. Since individuals with
autism engage in minimal listener-oriented behaviour, they are a useful group to
differentiate these functions. Results showed that individuals with autism used fewer ums
and uhs, and more silent pauses than controls, but used animacy similarly. This suggests
that the use of ums and uhs is for the benefit of listeners, but the bias toward animate
subjects is not.

abstract: Thesis

abstract: Master of Science (MSc)


title: Credit Risk from Theory to Application

contributor:
Grasselli, Matheus
Mathematics

subject: credit risk, theory, application,interest rate, hazard rate, CIR model, factor

abstract:
 In this thesis, we calibrated a one factor CIR model for interest rate and a two factor
CIR model for each hazard rate of 21 firms. The time series of the interest rate and
each hazard rate for 21 firms are also obtained. Extended Kalman Filter and Quasi-Maximum
Likelihood Estimation are used as the numerical scheme. The empirical results suggest that multifactor CIR models are not better than multifactor Hull-White model. Positive correlations between hazard rate and interest rate are discovered, although most hazard rates are found to be negatively correlated with the default-free interest rate. The 21 filtered time series of the hazard rates suggest that there maybe a hidden common factor shared only by the intensities. Monte Carlo Simulation is conducted both for interest rate and hazard rates. The simulation indicate that both the SKF and the EKF work pretty well as a filter tool but may produce bad estimation for the value of the likelihood function. QMLE works fine in linear state space form
model, but it does a poor job in the case of non-linear state space form.

abstract: Thesis

abstract: Master of Science (MSc)


title: Orbifolds of Nonpositive Curvature and their Loop Space

contributor:
Boden, Hans U.
Mathematics and Statistics

subject: orbifolds, nonpositive, curvature, loop space

abstract:
Abstract Not Provided.
Thesis
Master of Science (MSc)


title: Spatial and Temporal Modelling of Water Acidity in Turkey Lakes Watershed

contributor:
El-Shaarawi, Abdel H.
Statistics

subject: spatial, temporal, modelling, Turkey Lakes, watershed, acidity, acid rain, change point, segment regression

abstract:
 Acid rain continues to be a major environmental problem. Canada has been monitoring indicators of acid rain in various ecosystems since the 1970s. This project focuses on the analysis of a selected subset of data generated by the Turkey Lakes Watershed (TLW) monitoring program from 1980 to 1997. TLW consists of a series of connected lakes where 6 monitoring stations are strategically located to measure the input from an upper stream lake into a down stream lake. Segment regression models with AR(1) errors and unknown point of change are used to summarize the data. Relative likelihood based methods are applied to estimate the point of change. For pH, all the regression parameters except autocorrelation have been found to change significantly between the model segments. This was not the case for SO4 2- where a single model was found to be adequate. In addition pH has been found to have a moderate increasing trend and pronounced seasonality while SO4 2- showed a dramatic decreasing trend but little seasonality. Multivariate dimension reduction methods are
used to provide an overall graphical summary of the changes in TLW water system. We also report the result of applying segment regression for the analysis of first two principal components in selected stations. The results show that the efforts of the Canadian and US governments to reduce the emission of SO2 have been successful in controlling the acid rain problem in Eastern Canada. The project ends with suggestions for various extensions of the present work.

abstract: Thesis

abstract: Master of Science (MSc)


title: Dihomotopy and Concurrent Computing

contributor:
Nicas, Andrew
Mathematics

subject: dihomotopy, concurrent, computing

abstract: Concurrent Computing has certain interesting links with Algebraic Topology. There are various geometric models for concurrent computing. We examine one geometric approach to modeling concurrency, via the notion of a locally partially ordered space. We examine a notion analogous to that of homotopy, called dihomotopy, that is compatible with a local partial order. In the category of locally partially ordered spaces and di-maps we examine the isomorphisms, which are called di-homeomorphisms. We classify all di-homeomorphic embeddings of the unit square into the Euclidean plane.

abstract: Thesis

abstract: Master of Science (MSc)


title: Alternate Duals of Gabor Subspace Frames

contributor:
Gabardo, Jean-Pierre
Mathematics and Statistics

subject: alterante duals, Gabor subspace frames, function, linear span, Bessel Collection, The Zak Transform

abstract:
 In this thesis we mainly give a characterization of dual frames of Gabor subspace frames. We give necessary and sufficient conditions for the existence and the uniqueness of a function h (called window) in the closed linear span of a Gabor subspace frame {EmbTnak}m,n∈Z such that the Bessel collection {EmbTnah}m,n∈Z serves as the dual frame of the original frame {EmbTnag}m,n∈Z. We solve the problem for three cases, first ab = 1, second ab = p ∈ N, and third ab = p/q, gcd(p, q) = 1. In each case, we first find the conditions for upper frame bound
(known as Bessel collection). Secondly, we characterize the functions which are orthogonal to {EmbTnag}m,n∈Z in terms of the Zak transform, and then obtain necessary and sufficient conditions for lower frame bound. Here we state obtained conditions for normalized tight frame as a corollary. Finally, using all this information we solve the duality problem.

abstract: Thesis

abstract: Master of Science (MSc)


title: Implementation of Pattern Matching Calculus Using Type-Indexed Expressions

contributor:
Kahl, Wolfram
Computing and Software

subject: pattern matching, calculus, type-indexed, expressions, programming

abstract:
 The pattern matching calculus introduced by Kahl provides a fine-grained mechanism of
modelling non-strict pattern matching in modern functional programming languages. By
changing the rule of interpreting the empty expression that results from matching failures,
the pattern matching calculus can be transformed into another calculus that abstracts a
"more successful" evaluation. Kahl also showed that the two calculi have both a confluent
reduction system and a same normalising strategy, which constitute the operational semantics
of the pattern matching calculi.

 As a new technique based on Haskell's language extensions of type-saft cast, arbitrary-rank polymorphism and generalised algebraic data types, type-indexed expressions introduced by Kahl demonstrate a uniform way of defining all expressions as type-indexed to guarantee type safety.

 In this thesis, we implemented the type-indexed syntax and operational semantics of the pattern matching calculi using type-indexed expressions. Our type-indexed syntax mirrors the definition of the pattern matching calculi. We implemented the operational semantics of the two calculi perfectly and provided reduction and normalisation examples that show that the pattern matching calculus can be a useful basis of modelling non-strict pattern matching.

 We formalised and implemented the bimonadic semantics of the pattern matching calculi
using categorical concepts and type-indexed expressions respectively. The bimonadic semantics employs two monads to reflect two kinds of computational effects, which correspond to the two major syntactic categories of the pattern matching calculi, i.e. expressons and matchings. Thus, the resulting implementation provides the detotational model of non-strict pattern matching with more accuracy.

 Finally, from a practical programming viewpoint, our implementation is a good demonstration of how to program in the pure type-indexed setting by taking fully advantage of Haskell's language extensions of type-safe cast, arbitrary-rank polymorphism and generalised algebraic data types.

abstract: Thesis

abstract: Master of Science (MSc)


title: Topics in One-Way Supervised Biclustering Using Gaussian Mixture Models

contributor:
McNicholas, Paul
Mathematics and Statistics

subject:
Biclustering
One-way supervision
Finite mixture models
Model-based clustering

abstract: Cluster analysis identifies homogeneous groups that are relevant within a population. In model-based clustering, group membership is estimated using a parametric finite mixture model, commonly the mathematically tractable Gaussian mixture model. One-way clustering methods can be restrictive in cases where there are suspected relationships between the variables in each component, leading to the idea of biclustering, which refers to clustering both observations and variables simultaneously. When the relationships between the variables are known, biclustering becomes one-way supervised. To this end, this thesis focuses on a novel one-way supervised biclustering family based on the Gaussian mixture model. In cases where biclustering may be overestimating the number of components in the data, a model averaging technique utilizing Occam's window is applied to produce better clustering results. Automatic outlier detection is introduced into the biclustering family using mixtures of contaminated Gaussian mixture models. Algorithms for model-fitting and parameter estimation are presented for the techniques described in this thesis, and simulation and real data studies are used to assess their performance.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Propositional Proof System with Permutation Quantifiers

contributor:
Soltys, Michael
Computing and Software

subject: propositional, proof, system, permutation quantifiers, Frege systems

abstract:
 Propositional proof complexity is a field of theoretical computer science which concerns
itself with the lengths of formal proofs in various propositional proof systems. Frege systems are an important class of propositional proof systems. Extended Frege augments them by allowing the introduction of new variables to abbreviate formulas. Perhaps the largest open question in propositional proof complexity is whether or not Extended Frege is significantly more powerful that Frege. Several proof systems, each introducing new rules or syntax to Frege, have been developed in an attempt to shed some light on this problem.

 We introduce one such system, which we call H, which allows for the quantification of transpositions of propositional variables. We show that H is sound and complete, and that H's transposition quantifiers efficiently represent any permutation.

 The most important contribution is showing that a fragment of this proof system, H*1, is equivalent in power to Extended Frege. This is a complicated and rather technical result, and is achieved by showing that H*1 can efficiently prove translations of the first-order logical theory ∀PLA, a logical theory well suited for reasoning about linear algebra and properties of graphs.

abstract: Thesis

abstract: Master of Science (MSc)


title: Analysis of Priorities of Patients Living with Diabetes

contributor:
Thabane, Lehana
Statistics

subject: priorities, patients, diabetes, symptoms, MANCOVA

abstract:
 Diabetes is a chronic disease that affects more than 2 million Canadians. In order to
reduce the risk of complications, people with diabetes must monitor their symptoms and actively manage diet, exercise, and medication. Patient priority is defined as the patient's implicit or explicit ordering of importance, ease and frequency of preventative or treatment activities for managing diabetes. In this study, we report on the findings of a questionnaire of diabetes patient priorities. The primary purpose of this study was to identify patient priorities and their relationships for managing diabetes from a patient's perspective. Multivariate analysis techniques were applied to find the patterns within the ratings of importance, ease and frequency for seventeen diabetes care activities. Multivariate analysis is used when more than one measurement is taken on a given experimental unit and all the measurements need to be considered together so that one can understand how they are related and what the essential structure is. In our study, the multivariate techniques used were MANCOVA, multivariate regression, and factor analysis. Due to the missing values, simple and multiple imputations were necessary. This study acts as a pilot study for a future, larger study about patient priorities.

abstract: Thesis

abstract: Master of Science (MSc)


title: Design and Implementation of a Solver for High-Index Differential-Algebraic Equations

contributor:
Nedialkov, Ned
Computing and Software

subject: design, implementation, solver, high-index, differential-algebraic equations

abstract:
 Systems of differential-algebraic equations (DAEs) arise in numerious applications, and there has been considerable research on solving DAE initial value problems (IVPs). Existing methods and software for solving DAEs usually handle at most index-three problems. However, DAE problems of index three and higher do arise, for example, in actuator dynamics, multi-stage processes, and optimization.

 We present the method of J. Pryce and N. Nedialkov for solving DAEs, which can be of high index, fully implicit, and contain derivatives of order higher than one. We solve such DAEs by expanding their solution in Taylor series (TS). To compute Taylor coefficients, we employ J. Pryce's structural analysis and automatic differentiation. Then we compute an approximate TS solution with appropriate stepsize and project this solution to satisfy the constraints (explicit and hidden) of the problem.

 This thesis discusses the algorithms involved in this method, including the algorithms for Taylor coefficients computation, consistent point projection, error estimation, stepsize control, and the overall integration process. The author has implemented a software package named HIDAETS (High-Index DAE by Taylor Series). In this thesis, we present the specification, design, implementation, and usage of HIDAETS. Numerical results on several high-index DAEs are reported. These results demonstrate that HIDAETS is efficient and accurate for solving IVP in DAEs.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Wassyng, Alan
Computing and Software

abstract: Title: Documentation and Tools to Support Worst Case Execution Time Analysis, Author: Jian Sun, Location: Thode

abstract:
Knowing the timing behavior is essential when designing and inspecting real-time systems. Especially, the Worst Case Execution Time (WCET) of a program is of the utmost importance for schedulability and other timing analyses. The industrial deployment of critical systems presents an urgent need for WCET analysis methods and tools.

This thesis represents how the Display documentation method, introduced by Parnas and his colleagues in [32], is extended and used to aid WCET analysis and WCET Tool development. The work is performed within a Reverse Engineering Project, which has to recover high-level requirements of IBM 1800 assembler applications. Specifically, the displays are (primarily) manually composed from code, and
then used by timing analysts for program understanding and flow analysis, which are essential phases in timing analysis. The thesis combines the Display documentation method with the WCET analysis techniques to solve several general problems in determining the upper bound of program execution time. It also includes a detailed example of a WCET, analysis tool based on the documentation method.

abstract: Thesis

abstract: Master of Science (MS)


title: High Throughput Screening of Nanoparticle Flotation Collectors

contributor:
Pelton, Robert H.
Chemical Engineering

subject:
Nanoparticle Flotation Collectors
High Throughput Screening
Nanoparticles
Flotation
High Throughput
Click Chemistry

abstract: Carla Abarca Ph.D. Thesis

abstract:
The selective separation of valuable minerals by froth flotation is a critical unit operation in mineral processing. Froth flotation is based on the ability of chemical reagents, called collectors, to selectively lower the surface energy of valuable mineral particles, facilitating attachment of the modified mineral particles to air bubbles in the flotation cell. The mineral laden bubbles rise to the surface forming a froth phase that can be isolated.
Novel cationic polystyrene nanoparticle collectors have been developed recently to be used as effective flotation collectors, aiming to recover challenging nickel sulfide ores that respond poorly to conventional molecular flotation collectors. However, optimizing nanoparticle flotation collectors is a challenge. An effective nanoparticle collector candidate should meet three requirements: (1) it should be colloidally stable in the flotation media; (2) it should be hydrophobic enough to change the mineral surface and induce an air bubble-mineral particle attachment; and (3) specifically and strongly bind to metal-rich minerals. Producing nanoparticles that are simultaneously colloidally stable and sufficiently hydrophobic presents a problematic task. Thus, a delicate balance of nanoparticle properties is required for commercially viable nanoparticle collectors.
This thesis presents a promising approach for discovering and characterizing novel nanoparticle collectors by using high throughput screening techniques. Developed was a workflow for fast fabrication and testing of nanoparticle candidates, including: (1) parallel production of large nanoparticle libraries covering a range of surface chemistries, (2) a high throughput colloidal stability assay to determine whether a nanoparticle type is stable in flotation conditions; (3) an automated contact angle assay to reject nanoparticles that are not hydrophobic enough to induce efficient bubble-particle attachment, and; (4) a laboratory flotation test in sodium carbonate (pH~10) with the best nanoparticle candidates.
The automated colloidal stability assay was based on the optical characterization of diluted nanoparticle dispersions in multiwell plates, yielding critical coagulation concentrations (CCCs) of sodium carbonate. To pass this screening test, the CCC of candidate nanoparticles must be greater than the effective carbonate concentration in commercial flotation cells. Since the nanoparticle size affects the intrinsic light scattering properties of the nanoparticles, two routes were developed. The colloid stability assay was suitable for nanoparticles ranging between 50 nm and 500 nm, since nanoparticle size.
The automated contact angle assay used a miniature 16-well plate format where flat glass slides were exposed to 200 μL nanoparticle dispersions. The cationic nanoparticles formed a saturated adsorbed monolayer on the glass, and after rinsing and drying, the water contact angle was automatically measured. Effective nanoparticle candidates had contact angles greater than 50 degrees, a criterion developed with model experiments.
During the development of the automated workflow platform, a series of nanoparticles with methyl-ended PEG-methacrylate monomers were prepared. Although the PEG chains greatly enhanced colloidal stability, the particles were too hydrophilic to be effective collectors. Interestingly, nanoparticles with long PEG chains acted as froth modifiers, giving wetter and more robust foams as well as increased entrainment of materials that did not adhere to bubbles.
Conventional laboratory scale latex synthesis methodologies are far too inefficient to generate large library of candidate nanoparticles. Instead, we started with a few parent nanoparticle types and then used Click chemistry to generate a large range of surface chemistries. Specifically copper-mediated azide alkyne cycloaddition reaction was used to functionalize the surface of azide nanoparticles with different chemical groups, ranging from hydrophilic amine-terminated PEG chains, to hydrophobic hexane-terminated materials.
The Click library exhibited an extensive range of critical coagulation concentrations and contact angle values. For example, for a given parent azide nanoparticle, the contact angles ranged from 62 to 101 degrees, depending upon the density and type of click reagent. A novel paper chromatographic method was developed for the quantitative determination surface azide. This assay was critical for determining the surface density of functional groups from the click reactions.
Overall, high throughput screening techniques were designed and applied to the development of nanoparticle collectors for froth flotation. Automated screening assays of critical coagulation concentration and contact angle proved to be effective in obtaining flotation domain maps, and finding the most promising nanoparticle collectors for froth flotation. I believe the work in this thesis is one of the first reported uses of high throughput methodologies for the development of mineral flotation reagents.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Novel cationic polystyrene nanoparticle collectors have been developed to be used as effective flotation collectors, aiming to recover challenging nickel sulfide ores that respond poorly to conventional molecular flotation collectors. However, optimizing nanoparticle flotation collectors is a challenge. This thesis presents a promising approach for discovering and characterizing novel nanoparticle collectors by using high throughput screening techniques and click chemistry. Development of nanoparticle libraries and automated screening assays of critical coagulation concentration and contact angle proved to be effective in obtaining flotation domain maps, and finding the most promising nanoparticle collectors for froth flotation.


contributor:
Lawford, Mark
Parnas, David
Computing and Software

abstract: Title: Inspection of Concurrent Systems: Combining Tables, Theorem Proving and Model Checking, Author: Vera Pantelic, Location: Thode

abstract:
A process for rigorous inspection of concurrent systems using tabular specification
was developed and applied to the classic Readers/Writers concurrent program by Jin
in [15]. The process involved rewriting the program into a table and then performing
a manual "column-by-column" inspection for safety and clean completion properties.
The key element in the process is obtaining an invariant strong enough to prove
the properties of interest. This thesis presents partial automation of the proposed
approach by combining theorem proving and model checking. Model checking is first
used to validate a formal model of the system with a small, fixed number of concurrent
process instances. The verification of the system for an arbitrary number of processes
is then performed using theorem proving together with model checking on the earlier
model to quickly validate potential invariants before they are used in the formal
proof. This method was used to check the manual proof of the Readers/Writers
problem given in [15], discovering several random and one systematic mistake of the
proof. Then, a new, significantly automated proof was performed.

abstract: Thesis

abstract: Master of Applied Science (MASc)


contributor:
Wilson, Margo
Daly, Martin
Psychology

abstract: Title: Factors Associated with Hamilton, Ontario Women's Marital Surname Change Attitudes, Author: Melanie MacEacheron, Location: Thode

abstract:
132 female, never-married, undergraduate psychology students were surveyed
regarding attitudes concerning taking their husband's surname upon marriage. It was
hypothesized that approval of such a surname change would be associated with their views
on (1) resource transfer from, and involvement with, in-laws, and (2) the importance of
high resource potential in a candidate husband. Lesser approval of taking husband's
surname was significantly predicted under OLS regression by desire for in-laws to be
uninvolved with the newlywed couple and their children. The importance of resource-holding
potential in a candidate husband was a marginally significant predictor, moderated
by the women's own mothers' taking of their fathers' surnames, as well as by how
emotionally close these women were to their mothers. Retaining or hyphenating one's pre-marital surname among brides marrying in
Hawaii in 2006, was significantly correlated with average income of women and the
average income of men in the bride's state of residence, with only that of women,
however, being a marginally-significant predictor where both were used as regression
predictors of retention or hyphenation. Older brides were more likely to hyphenate or
retain their pre-marital surnames upon marriage in Hawaii in 2006.

abstract: Thesis

abstract: Master of Science (MSc)


title: A Multi-Learner, Multi-Level, Multi-Competency Simulation Approach to Competency-based Education of Obstetrical Emergenices

contributor:
Grierson, Lawrence
Health Science Education

subject: simulation, competency based, obstetrical emergencies

abstract:
The CanMEDS 2015 Framework outlines many key competencies that must be addressed during residency training. The move towards the “Competency by Design” curriculum will require the use of simulation for assessment of these competencies. However, the use of simulation poses many challenges for residency programs including meeting the learning needs of multiple levels of learners, financial constraints, time constraints etc.
We performed a program evaluation on an obstetrical emergencies simulation curriculum that involved Obstetrics and Gynecology residency trainees (PGY1-PGY5). Different levels of learners participated in various roles including; first responder (PGY2), second responder (PGY5), confederate roles including patient, nurse or family member (PGY1-3) and assessor (PGY4). This permitted assessment of the following CanMEDS competencies: medical expert and communicator (PGY2); communicator and leader (PGY5); communicator, collaborator and health advocate (PGY1-3) and scholar (PGY4).
We were able to determine financial costs, faculty time, and resident time for our existing simulation curriculum and our new simulation curriculum.
Residents were surveyed prior to the simulation regarding the learning environment in our pre-existing simulation curriculum and self-efficacy ratings for the competencies mentioned above. Faculty were also surveyed prior to the simulation regarding the residents’ competencies. Station scores were collected for all competencies. Focus groups allowed further exploration of the residents’ and faculty perceptions of the new simulation experience. Lastly, post-simulation surveys of both residents and faculty
allowed comparison of pre- and post- learning environment assessment and self-
efficacy/performance scores.
We had limited station scores from our pre-existing simulation curriculum to allow direct comparison between the specific scenarios
The program evaluation determined that this method of incorporating multiple levels of learners provided a feasible and acceptable method of assessing multiple CanMEDS competencies while minimizing financial costs and significantly reducing faculty time requirements.

abstract: Thesis

abstract: Master of Science (MSc)

abstract:
This study examined a simulation curriculum for obstetrical emergencies using multiple postgraduate learners in various roles, to provide a learning opportunity and assessment opportunity, for a number of skills required by the Royal College of Physicians & Surgeons of Canada.
It was found that involving learners in various roles, including responders; confederates acting as nurses, patients and family members; and assessors, enhanced learning in regards to patient management, communication, collaboration, assessment and health advocacy while reducing financial costs and faculty time requirements.


title: Symbolic Interpretation of Legacy Assembly Language

contributor:
Carette, Jacques
Computing and Software

subject: symbolic, interpretation, legacy assembly language, control flow

abstract:
 Many industries have legacy software systems which are definitely important to them but are however, difficult to maintain due to a lack of understanding of those systems. This occurs as a result of inadequate or inconsistent documentation. Although the costs of redesigning the system may be large, some organizations still plan to reverse engineer the software specification documents from the code to alleviate a large burden from such endeavour. This thesis provides an incremental and modular approach to create a process and tools to extract the semantics of legacy assembly code.

 Our techniques consist of static analysis and symbolic interpretation in order to reverse engineer the semantics of legacy software. We examine the case of IBM-1800 programs in detail. From the abstract model of the operational semantics of IBM-1800, we simultaneously obtain an emulator and a symbolic analysis process. Augmented with control flow information, we can use the symbolic analysis to provide
complete semantics for the code sequences of interest. We can also generate Data Flow Graphs to depict the flow of data in those code segments. The whole process of extracting semantic information from the assembler codes is fully automated with only a little human intervention at the initial step.

 We use Haskell as our implementation language and its important features help us to create modular and well structured software. The literate programming documentation style in this thesis increases the readability and consistency of the implementation's documentation.

 The process and the associated tools created in this thesis are used in a large reverse engineering project, which has a goal to extract requirements specification from legacy assembly code. This project is funded jointly by Ontario Power Generation (OPG) and CITO (Communications and Information Technology Ontario).

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Computing the Effective Hamiltonian in the Majda-Souganidis Model

contributor:
Tourin, Agnès
Mathematics and Statistics

subject: effective Hamiltonian, computing, Majda-Souganidis Model, turbulent combustion, eigenvalue

abstract:
 In premixed turbulent combustion, the normal speed of propagation of the flame front is enhanced by the turbulent velocity field. This project will focus on the method of computing the normal speed of propagation of the flame front in the Majda-Souganidis model of turbulent combustion. Solving this problem involves computing the eigenvalue of a nonlinear cell problem. Discussed in this thesis is a new, simple and direct numerical method for
approximating the eigenvalue, also called the effective Hamiltonian.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Thabane, Lehana
Science

abstract: Title: A Look at Factors that Impact Growth in Churches of the Evangelical Mennonite Mission Conference, Author: Eddy Rempel, Location: Thode

abstract:
Canadian domination of Christianity is challenged by eastern religions.
Affiliation with the Mennonite faith fell 8% from 1991 to 2001 . The Evangelical
Mennonite Mission Conference (EMMC) recently adopted a regional structure
across Canada, the United States, Mexico, and Belize. It wishes to measure its
recent growth rate and investigate growth factors across regions.

Using EMMC Records of church membership and attendance, surveys of
senior pastors and church leaders, we grouped the 37 churches by region., size,
and growth status, modelled church growth using univariate and multivariable
models.

Leaders perception of occupation and activity faith would compromises
their faith and the level of assistance their church required and received, and
expectation of five-year change in their church attendance were modelled using
generalized estimating equations.

Attendance growth varied across regions and church size - small (0-99;
9%), medium (100-299; 14.2%), and large (300+; -3%). For 33 of 37 responding
senior pastors 61% of new members were transferees, few churches took listed
growth promotion steps, 54% of attendees attend Sunday school, 26% attend
Bible study, 30% attended the last annual meeting 42% received a donation
receipt, 91% own their building, 70% have the worship space filled less than 80%
capacity, 77% had a single board, and 59% had board term limits and the senior
pastor overseeing other pastors. None of the tested factors predicted change in
attendance.

Almost half (49%) of 517 EMMC registered leaders completed the
questionnaire. Of these 87% claimed Mennonite ancestry. The scores
measuring the opinionated degree that particular jobs and activities would
compromise their faith were higher for leaders with university education, first
speaking Plautdietsch, in Mexico or Belize but lower in Saskatchewan. Leaders
at new and small churches believe their churches require and received more
assistance than those from large churches. The church required assistance
score was substantially higher than the received assistance (mean 16.0 vs. 9.4).

In spite of apparent robust growth in the EMMC, this growth is limited to
the frontier regions. The demographics of the leaders indicate that outreach to
other ethnic groups has not produced leaders yet. We did not identify any factors
associated with growth.

abstract: Thesis

abstract: Master of Science (MS)


contributor:
Karakostas, George
Computing and Software

abstract: Title: Queueing Networks with Limited Flexibility, Author: Liuxing Kan, Location: Thode

abstract:
Queueing network models have been widely adopted in the field of complex systems
involving service. In this thesis, we study a queueing network model which consists
of servers and classes with incoming customers. Customers are served by servers at
classes, where a class of a customer is used to indicate the stage of processing. All
the servers are flexible to switch their service between classes. Our objective is to
choose an efficient assignment of servers to classes that maximizes the capacity of t he
given queueing network. By introducing limited flexibility, we restrict the maximum
number of servers which can simultaneously work at a particular class and present
a problem called the Total Discrete Capacity Constrained Problem (TDCCP). We
also extend TDCCP to TDCCP with costs, where a cost is incurred when a server is
working at a class.

We prove that both TDCCP and TDCCP with costs are NP-complete problems.
However, for a special case where all servers are identical, we show that TDCCP and
TDCCP with costs can be solved in polynomial time. Then we present approximation algorithms for another special case where all classes are identical. We also give
approximation algorithms for solving the general case of TDCCP and TDCCP with
costs.

Finally, we implement the approximation algorithms for solving TDCCP and TDCCP
with costs. Numerical results on several experiments are reported. We compare
and analyze the performance of the different algorithms. Several suggestions will be
also given for choosing our algorithms and improving the results.

abstract: Thesis

abstract: Master of Science (MSc)


title: Synthesis and Evaluation of [2 + 1] Re(I) and 99mTc(I) Complexes: New Synthons for the Preparation of Isostructural Optical and Nuclear Probes

contributor:
Valliant, John F.
Chemistry

abstract:
The synthesis, stability and photophysical properties of [2 + 1] Re(I) and Tc(I) complexes derived from bipyridine type ligands and a series of imidazole derivatives were investigated as a means of identifying complexes suitable for creating targeted isostructural optical/nuclear molecular imaging probes. The first generation complexes were prepared by combining [Re(CO)3(H2O)3]Br with 2,2'-bipyridine (bipy) to give [Re(CO)3(bipy)Br], which in turn was converted to the desired complexes by treatment with functionalized imidazoles. All products were fully characterized by conventional methods which included crystal structures of two new Re complexes. The corresponding 99mTc complexes [99mTc(CO)3(bipy)(L)]n (L = imidazole derivatives) were prepared by combining [99mTc(CO)3(bipy)(H2O)]Cl with the same series of monodentate ligands used with Re(I) and heating at 40 °C or 60 °C for 30 min. Quantitative transformation to the final products was confirmed in all cases by HPLC and the nature of the complexes verified by comparison to the authentic Re standards. Incubation in saline and plasma, and amino acid challenge experiments showed that N-substituted imidazole derivatives, bearing electron donating groups, exhibited superior stability to analogous metal complexes derived from less basic ligands. Imaging studies in mice revealed that with the appropriate choice of monodentate ligand, it is possible to prepare robust [2 + 1] Tc complexes that can be used as the basis for preparing targeted isostructural optical and nuclear probes.
The synthesis, stability, photophysical properties and in vivo biodistribution of [M(CO)3(BPS)(L)]n (M = Re/99mTc, BPS = bathophenanthroline disulfonate, L = imidazole derivatives) were investigated as a second generation of isostructural multimodal optical and nuclear probes. [Re(CO)3(BPS)(MeIm)]- (MeIm = methylimidazole) was prepared in high yield as a model compound and showed enhanced optical properties to the corresponding bipy analogue. To prepare the radiolabeled compounds, BPS was added to [99mTc(CO)3(H2O)3]+ and the mixture heated to 40 °C for 15 min. The product, [99mTc(CO)3(BPS)(H2O)]- was immediately treated with N-methylimidazole (MeIm) and with heating at 40 °C for 15 min yielding [99mTc(CO)3(BPS)(MeIm)]- 3b in nearly quantitative radiochemical yield. A targeted analogue [99mTc(CO)3(BPS)(ImAln)]2- (ImAln = imidazolealendronate) capable of binding regions of calcium turn-over associated with bone metabolism was also created. Biodistribution studies showed that the targeted [99mTc(CO)3(BPS)(ImAln)]2- analogue cleared rapidly from non-target tissues and had significant accumulation in the shoulder (7.9  0.2% ID/g) and knees (15.1  0.9 % ID/g) by 6 h, with long residence in the skeleton, up to 24 h. The isostructural Re(I) analogue [Re(CO)3(BPS)(ImAln)]2- was incubated with MCF-7 cells and fluorescence microscopy used to detect the probe that was located predominantly in the cytoplasm.
Having demonstrated in vivo targeting, [2 + 1] complexes of 99mTc(I) linked to a tetrazine were prepared and their utility for preparing radiopharmaceuticals using bioorthogonal chemistry was evaluated. Specifically, complexes of the type [99mTc(CO)3(N^N)(L)]n (N^N = BPS and bipy), where the monodentate ligand (L) was a tetrazine linked to the metal through an imidazole group, were prepared in nearly quantitative radiochemical yield by adding [99mTc(CO)3(N^N)(H2O)]n to the imidazole-tetrazine ligand and heating at 60 °C for 30 min. Measurement of the kinetics of the reaction between 10b and trans-cycloocteneol showed a second rate order constant of 8.6 × 103 M-1S-1 at 37 °C, which is suitable for pretargeting strategies that require rapid coupling to be effective in vivo. Stability studies showed that the products are resistant to ligand challenge and suitable for in vivo imaging. Biodistribution studies of the more water soluble BPS derivative in normal mice using pre-administered bisphosphonate conjugate of trans-cyclooctene (TCO-BP) showed high activity concentrations in the knee (9.27  0.32% ID/g) and shoulder (5.28  0.67% ID/g). SPECT/CT images showed that the [2 + 1] complex could also be used to visualize the damage associated with a bone tumor in a murine model further demonstrating the utility of this class of compounds for preparing new radiopharmaceuticals.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Design of a Configurable Alternate Fuel Injection Controller

contributor:
M., v. Mohrenschildt
Computing and Software

subject: design, configurable, alternate fuel injection controller, engine, energy

abstract:
 This thesis presents a strategy for documenting real-time control systems, and the work products that result from its application to the development of an alternate fuel injection controller. In doing so, this document contributes technically to the areas of automotive control, and control systems documentation. The strategy was not developed independently of the control system, but in a manner which reflects its size and complexity.

 The controller is used to generate and transmit appropriately timed and sized pulses to an alternative fuel injector array, and switch auxiliary devices including a fuel heater, and an injector lock-off. Such a controller, when used to inject natural gas or propane into a gasoline burning engine, provides a reduction in both engine operating costs and harmful engine emissions.

 The controller stores a fuel map that relates the amount of energy released by the combustion of petroleum to that released by the combustion of an alternate fuel, over a range of varying environmental conditions. The fuel map is used to calculate the
length of alternate injection pulses. These maps have been designed by, and are the property of Cosimo's Garage Ltd. and thus will not appear in this document.

 At present, nearly all large engine car conversion technology is more rigid than the solution provided here. Conversion costs are often prohibitive and problems requiring professional service are frequent. Should the controller described here, help to curb conversion costs and reduce the need for frequent service as is expected, the controller will be a viable candidate for production and sale.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: A Heat-Transfer Optimization Problem

contributor:
Terlaky, Tamás
Nedialkov, Nedialko
Mathematics and Statistics

subject: heat-transfer, optimization, problem, discretization, dimensions

abstract: Page IV was not included in the thesis, and thus not included in the page count.

abstract:
 Discretization is an important tool to transfer optimization problems that include differentiations and integrals into standard optimization problems with a finite number of variables and a finite number of constraints. Recently, Betts and Campbell proposed a heat-transfer optimization problem that includes the heat partial differential equation as one of its constraints, and the objective function includes integrals of the temperature function squared.
Using discretization methods, this problem can be converted to a convex quadratic optimization problem, which can be solved by standard interior point method solvers in polynomial time.

 The discretized model of the one dimensional problem is further analyzed, and some of its variants are studied. Extensive numerical testing is performed to demonstrate the power of the "discretize then optimize". Then the heat transfer optimization problem is generalized to two dimensions, and the discretized model and computational comparisons for this variant are included.

 Flexibility of discretization methods allow us to apply the same "diseretize then optimize" methodology to solve optimization problems that include differential and integral functions as constraints or objectives.

abstract: Thesis

abstract: Master of Science (MSc)


title: Modelling Disease in the Chemostat

contributor:
Wolkowicz, Gail S. K.
Mathematics

subject: disease, chemostat, modelling

abstract:
Abstract Not Provided.
Thesis
Master of Science (MSc)


title: The returned soldier

subject:
Reconstruction (1914-1939)
Veterans > Social conditions
Veterans > Economic conditions
Reconstruction (1914-1939) > Canada
Military pensions
Canada

abstract:
Thesis
Master of Arts (MA)


title: Models for Systemic Risk

contributor:
Hurd, Thomas R.
Mathematics and Statistics

subject:
Systemic Risk
Math Finance
Random Graph Theory
Portfolio Theory

abstract:
Systemic risk is the risk that an economic shock may result in the breakdown of the fundamental functions of the financial system. It can involve multiple vectors of infection such as chains of losses or consecutive failures of financial institutions that may ultimately cause the failure of the financial system to provide liquidity, stable prices, and to perform economic activities. This thesis develops methods to quantify systemic risk, its effect on the financial system and perhaps more importantly, to determine its cause.

In the first chapter, we provide an overview and a literature review of the topics covered in this thesis. First, we present a literature review on network-based models of systemic risk. Finally we end the first chapter with a review on market impact models.

In the second chapter, we consider one unregulated financial institution with constant absolute risk aversion investment risk preferences that optimizes its strategies in a multi asset market impact model with temporary and permanent impact. We prove the existence and derive explicitly the optimal trading strategies. Furthermore, we conduct numerical exploration on the sensitivity of the optimal trading curve. This chapter sets the foundation for further research into multi-agent models and systemic risk models with optimal behaviours.

In the third chapter, we extend the market impact models to the multi-agent setting. The agents follow a game theoretic strategy that is constrained by the regulations imposed. Furthermore, the agents must liquidate themselves if they become insolvent or unable to meet the regulations imposed on them. This paper provides a bridge between market impact models and network models of systemic risk.

In chapter four, we introduce a financial network model that combines the default and liquidity stress mechanisms into a ``double cascade mapping''. Unlike simpler models, this model can quantify how illiquidity or default of one bank influences the overall level of liquidity stress and default in the system. We derive large-network asymptotic cascade mapping formulas that can be used for efficient network computations of the double cascade. Finally we use systemic risk measures to compare the results of including with and without an asset firesale mechanism.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: CFD STUDY OF THE DEVELOPMENT OF INTER-SUBCHANNEL ISOTHERMAL LAMINAR FLOWS

contributor:
Tullis, Stephen
Lightstone, Marilyn
Mechanical Engineering

abstract:
The design and optimization of nuclear reactors, specifically in the case of CANDU, involves the study of subchannel flows. The mixing inside the subchannels is crucial to the efficiency of heat transfer between the fuel rods and the coolant. Numerous studies have been done throughout the past few decades regarding the physics of subchannel flows, most of which being inside the turbulent regime.
Despite the fact that subchannel flows in nuclear reactors are turbulent in nature, studies have shown that flow pulsations inside subchannels can occur under laminar conditions. It is thus beneficial to study pulsations in laminar flows, as it avoids the complications of turbulent modeling, for a clear understanding of the cause and growth of the pulsations.
Laminar simulations of various experiments in subchannel flows were conducted in this study, with a focus on exploring the evolution of the pulsations. Initial developments of flow in different regions of the subchannels were observed along with their evolution and interactions with each other. Qualitative and quantitative results were analyzed to give a better understanding of the flow pulsations in laminar condition.

abstract: Thesis

abstract: Master of Applied Science (MASc)


contributor:
Sartipi, Kamran
Computing and Software

abstract: Title: Multi-view Software Architecture Reconstruction, Author: Nima Dezhkam, Location: Thode

abstract:
Most approaches in the reverse engineering literature generate a single view of a software
system. However, a single view recovery restricts the scope of the reconstruction
process to limited types of information. In this thesis, we propose a multi-view approach
that recovers three views of software systems: design, behavior, and structure.
The design view is reconstructed through transforming a number of task scenarios
into design diagrams (class diagrams, ER diagrams, and activity diagrams) using a
novel scenario domain model that allows us to parse the task scenarios and populate
an objectbase of actors and actions. The behavior view is represented through a
set of profiles that contain the dynamic information extracted from executing a set
of relevant task scenarios on the software system. This set of task scenarios covers
frequently used software features. The obtained profiling information serves as
the dynamic characteristics of the software system that would be embedded into the
structure view recovery. Finally, we propose a pattern based structure view recovery
that defines the high-level architecture of the software system using abstract components
and interconnections. In this context, both static and dynamic aspects of the
software system are used to collect software entities into cohesive components with
reduced dynamic interactions. The whole process is modelled as a Valued Constraint
Satisfaction Problem (VCSP). As a case study we applied

abstract: Thesis

abstract: Master of Applied Science (MASc)


contributor:
Lawford, Mark
Business

abstract: Title: Symbolic Timing Analysis of Real-Time Systems, Author: Mark H. Pavlidis, Location: Thode

abstract:
Timing analysis of a real-time control program is often required to verify that the system
meets timing requirements. For example, if a real-time control program responds
too slowly or too quickly, then the system may become unstable and fail. Traditional
methods to determine timing bound estimates are often restrictive, labour-intensive,
and error-prone. This thesis proposes an automated method of obtaining best- and
worst-case timing bounds on unstructured assembly code without the need for manual
annotation of loop or recursive call bounds. A prototype tool suite takes an
assembly program as input and then generates the static control-flow graph. The
generated static control-flow graph is then automatically translated into a timed automata
model that models instruction processing times and adds variables to model
the processor state. The resulting timed automata's transition relation represents the
dynamic control-flow graph of the program. Fastest and slowest trace algorithms in
recent prototype versions of UPPAAL, a timed automata model checker, are then used
to extract tight best- and worst-case execution times of the program. The method is
applied to code examples for two different low-end (i.e., no cache or pipeline) 8 and
16-bit microcontroller architectures, the PIC and IBM1800.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Polyhedra Computation Under Symmetry

contributor:
Deza, Antoine
Computing and Software

abstract: Title: Polyhedra Computation Under Symmetry, Author: Gabriel Indik, Location: Thode

abstract:
The last 15 years have seen significant progress in the development of
general purpose algorithms and software for polyhedral computation. Many
polytopes of practical interest have enormous output complexity and are often
highly degenerate, posing severe difficulties for known general purpose algorithms.
They are, however, highly structured and attention has turned to
exploiting this structure, particularly symmetry. We focus on polytopes arising
from combinatorial optimization problems. In particular, we study the metric
polytope associated to the well-known maxcut and multicommodity flow problems,
as well as to finite metric spaces. To tackle the huge size of the problem hundreds
of trillions of vertices - a parallel or bitwise enumeration algorithm was
implemented and run on Shared Hierarchical Academic Research Computing
Network (SHARCNET) clusters. Exploiting the high degree of symmetry, we
provide for t he first time a description of the highly degenerate metric polytope
in dimension 36. The description consists of 1 056 368 orbits and is conjectured
to be complete. While the validity of the dominating set conjecture [Laurent-Poljak,
1992] is proven for the overwhelming majority of the known vertices of
the metric polytope, we disprove the conjecture by exhibiting counterexamples
in dimensions 36 and 45.

abstract: Thesis

abstract: Master of Science (MS)


contributor:
Lovric, Miroslav
Mathematics and Statistics

abstract: Title: A Study on the Transition of Studies From High School to University Calculus at McMaster University, Author: Marcella Fioroni, Location: Thode

abstract:
For many students, the transition from high school to university is difficult. This thesis
uses data from a Mathematics Background Questionnaire ("the survey"), completed by
first year mathematics students at McMaster University, to answer several questions
related to transition in first year Calculus. In addressing these questions, we establish that
transition from high school to university mathematics is, in fact, a problem here at
McMaster and claim that the Mathematics Background Questionnaire can be used as a
tool to help overcome some of these transitional barriers.

The purpose of this study is twofold. Firstly, the study examines students' responses to
the survey, and seeks a relationship between these responses and overall performance in
the course MATH 1A3. A second purpose for this study is to monitor student
performance over the years 2002, 2003 and 2005, based on background information and
the results of a particular survey question. This is interesting and valuable information
since this period includes the students before, during and after the double cohort group.

It was found that students before and during the double cohort year (2002 and 2003)
performed better both on the survey and in MATH 1A3 than the students after the double
cohort year (2005). We discuss possible reasons for this; for example, fewer high school
mathematics courses taken by the students in 2005 and problems with implementation of
the new high school mathematics curriculum in 2000.

Our most important result is that our survey data revealed the following relationship: high
survey scores are indicative of high overall final grades in MATH 1A3; low survey
scores do not predict overall final grades. Thus, based on our ability to use our
questionnaire to make predictions about a student's performance, we can take steps
towards helping students make their transition to university calculus more successful. At
this point, it is important to focus on incorporating survey feedback to students so that
they have a better idea of what to expect in MATH 1A3 and how to proceed in the
course.

abstract: Thesis

abstract: Master of Science (MS)


contributor:
Wassyng, Alan
Computing and Software

abstract: Title: Towards Automated Construction of Tabular Expressions, Author: Yazhi Wang, Location: Thode

abstract:
Deriving precise descriptions of existing programs using automated actions plays a
significant role in software engineering, especially in projects that are not well documented.
Tabular expressions (tables) are practical formalized specification notations
that can be used in place of conventional mathematical expressions. Building function
tables from source code is a tremendous aid to understand the behavior of target
programs for inspectors and maintainers. However, generating those tables manually
is tedious and time consuming.

This thesis presents an automated method that will help extract vector function
tables from imperative programs in C. By dealing with the three primitive constructs
(assignments, alternations, iterations) we aim to translate the target programs into
functional documentation using tabular expressions. We discuss the difficulties we
encountered and t he methods we chose to overcome t hose difficulties. Loop termination
and pattern matching are also discussed in our analysis. Currently, we stop
short of producing the tabular expressions, but it is easy to see that tables can be
generated from the expressions produced by our tool.

abstract: Thesis

abstract: Master of Science (MS)


contributor:
Brooks, L.R.
Psychology

abstract: Title: The Effect of Difficult Recognition on Accuracy of Recall: Evidence for Modality Specific Processing, Author: Ian M. Thurston, Location: Thode

abstract:
Recall of visual or auditory first halves of lists of digits was
reduced if auditory recognition of the second halves was made difficult
by adding speech noise. Making visual recognition of the second halves
difficult by adding visual overlay produced no such reduction of first
half recall.

The observed retroactive effect on retention caused by difficult
auditory, but not difficult visual recognition, indicates that visual
recognition is in one system while rehearsal and auditory recognition
is in another. It also suggests that the correct explanation of the
retroactive effect of auditory noise is that rehearsal and auditory
recognition share processing capacity.

abstract: Thesis

abstract: Master of Arts (MA)


title: Evaluation of Seismic Design Criteria for Sliding Objects in Nuclear Facilities

contributor:
Konstantinidis, Dimitrios
Civil Engineering

subject: sliding components, nuclear facilities, earthquake excitation, ASCE 43-05, reserve energy method, sliding spectra

abstract:
Sliding is recognized as a dominant response mode for unanchored stocky components in
nuclear facilities. Although unanchored components are themselves not safety-critical,
their interaction with safety-critical systems and components during earthquake shaking
can have significant consequences. It is therefore important to be able to accurately
estimate the peak sliding displacement demands on unanchored components so that
sufficient clearance is provided around them. In lieu of nonlinear time history analysis,
the ASCE/SEI 43-05 standard provides an approximate method to estimate the maximum
sliding displacement of sliding objects in nuclear facilities. The present paper assesses the
procedure of the approximate method and compares its results to those of nonlinear time
history analysis. The study finds that the ASCE 43-05 approximate method provides
conservative sliding estimates overall and that is based on the three components of 7
modified and 159 real earthquake motions used in this study. It is concluded that the
ASCE 43-05 approximate method offers reasonable sliding estimates of components in
nuclear facilities.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: A Proof-of-Concept for Using PVS and Maxima to Support Relational Calculus

contributor:
Khedri, Ridha
Computing and Software

subject: PVS, maxima, relational calculus, proof-of-concept

abstract:
 Mechanized mathematics systems, especially Theorem Provers (TP) and Computer
Algebra Systems (CAS), can play a very helpful role in handling relational calculus. Computer Algebra Systems help to automate tedious symbolic computations. However, they lack the ability to make sophisticated derivations of logical formulas. Correspondingly, a Theorem Prover is powerful in deriving the truth-value of a logical formula. Nevertheless, it is not suitable for dealing with symbolic expressions.

 The main goal for our research is to investigate the automation of relational calculus using existing mechanized mathematics technologies. Particularly, we elaborated a heuristic that enables the assignment of tasks to PVS and Maxima to help perform relational calculus. As well we built a proof-of-concept tool that supports this calculus.

 To fulfill our objective, we adopted the following steps:
1. Investigated and evaluated the characteristics and capabilities of TPs and CASs. This step led us to select PVS and Maxima as the tools to be used by our system.
2. Explored a strategy that governs setting tasks to PVS and Maxima in order to perform relational calculus. Then, we propose a task assignment heuristic based on this strategy.
3. Designed and built a proof-of-concept tool that makes use of PVS and Maxima to help perform relational calculus.
4. Assessed our tool by using it to handle some illustrative examples of operations on concrete relations.

 In our work, relations are given by their characteristic predicates. We assume as well that predicates that are provided to our proof-of-concept tool are in a Disjunctive Normal Form. We adopt a linear notation for the representation of propositions, quantifications, and expressions. We fall short of providing a user interface, which makes the use of the tool that we built slightly difficult.

abstract: Thesis

abstract: Master of Science (MSc)


title: Approximation to K-Means-Type Clustering

contributor:
Peng, Jiming
Computing and Software

subject: approximation methods, clustering analysis, K-means, principal component

abstract:
 Clustering involves partitioning a given data set into several groups based on some similarity/dissimilarity measurements. Cluster analysis has been widely used in information retrieval, text and web mining, pattern recognition, image segmentation and software reverse engineering.

 K-means is the most intuitive and popular clustering algorithm and
the working horse for clustering. However, the classical K-means suffers from several flaws. First, the algorithm is very sensitive to the initialization method and can be easily trapped at a local minimum regarding to the measurement (the sum of squared errors) used in the model. On the other hand, it has been proved that finding a global minimal sum of the squared errors is NP-hard even when k = 2. In the present model for K-means clustering, all the variables are required to be discrete and the objective is nonlinear and nonconvex.

 In the first part of the thesis, we consider the issue of how to derive an optimization model to the minimum sum of squared errors for a given data set based on continuous convex optimization. For this, we first transfer the K-means clustering into a novel optimization model, 0-1 semidefinite programming where the eigenvalues of involved matrix argument must be 0 or 1. This provides an unified way for many other clustering approaches such as spectral clustering and normalized cut. Moreover, the new optimization model also allows us to attack the original problem based on the relaxed linear and semidefinite programming.

 Moreover, we consider the issue of how to get a feasible solution of the original clustering from an approximate solution of the relaxed problem. By using principal component analysis, we construct a rounding procedure to extract a feasible clustering and show that our algorithm can provide a 2-approximation to the global solution of the original problem. The complexity of our rounding procedure is O(n^(k2(k-1)/2)), which improves substantially a
similar rounding procedure in the literature with a complexity O(n^k3/2). In particular, when k = 2, our rounding procedure runs in O(n log n) time. To the best of our knowledge, this is the lowest complexity that has been reported in the literature to find a solution to K-means clustering with guaranteed quality.

 In the second part of the thesis, we consider approximation methods for the so-called balanced bi-clustering. By using a simple heuristics, we prove that we can improve slightly the constrained K-means for bi-clustering. For the special case where the size of each cluster is fixed, we develop a new algorithm, called Q means, to find a 2-approximation solution to the balanced bi-clustering. We prove that the Q-means has a complexity O(n^2).

 Numerical results based our approaches will be reported in the thesis as well.

abstract: Thesis

abstract: Master of Science (MSc)


title: Exploring Spacetime and Singularities

contributor:
Wang, M.
Mathematics

subject: spacetime, singularities, cosmological, Hawking's Theorem

abstract: Hawking's Singularity Theorem establishes the existence of a cosmological singularity in a spacetime for which no global assumptions about causality are made. This theory has been useful for predicting the occurrence of singularities in a spacetime without solving Einstein's field equation. This paper is an exposition of the tools and some of the theory required to prove and apply Hawking's theorem. Emphasis is placed on practical methods for applying this result to the flat, dust-filled Robertson-Walker spacetime, and the black hole interior of the Kruskal extension of the Schwarzschild spacetime.

abstract: Thesis

abstract: Master of Science (MSc)


title: Optimal Progressive Type-II Censoring Schemes for Non-Parametric Confidence Intervals of Quantiles

contributor:
Balakrishnan, N.
Statistics

subject: confidence interval, interval mass, mixture representation, non-parametric inference, optimal censoring scheme, order statistic, progressive Type-II censoring, quantile

abstract:
 In this work, optimal censoring schemes are investigated for the non-parametric confidence intervals of population quantiles under progressive Type-II right censoring. The proposed inference can be universally applied to any probability distributions for continuous random variables. By using the interval mass as an optimality criterion, the optimization process is also independent of the actual observed values from a sample as long as the initial sample size n and the number of observations m are predetermined. This study is based on the fact that each (uncensored) order statistic observed from progressive Type-II censoring can be represented as a mixture of underlying ordinary order statistics with exactly known weights [11, 12]. Using several sample sizes combined with various degrees of censoring, the results of the optimization are tabulated here for a wide range of quantiles with selected levels of significance (i.e., α = 0.01, 0.05, 0.10). With the optimality criterion under consideration, the efficiencies of the worst progressive Type-II censoring scheme and ordinary Type-II
censoring scheme are also examined in comparison with the best censoring scheme
obtained for a given quantile with fixed n and m.

abstract: Thesis

abstract: Master of Science (MSc)


title: Optimal Subsampling of Finite Mixture Distribution

contributor:
MacDonald, Peter D. M.
Statistics

subject: optimal subsampling, finite mixture distribution, probability density

abstract:
 A mixture distribution is a compounding of statistical distributions, which arises when sampling from heterogeneous populations with a different probability density function in each component. A finite mixture has a finite number of components. In the past decade the extent and the potential of the applications of finite mixture models have widened considerably.

 The objective of this project is to add some functionalities to a package 'mixdist' developed by Du and Macdonald (Du 2002) and Gao (2004) in the R environment (R Development Core Team 2004) for estimating the parameters of a finite mixture distribution with data grouped in bins and conditional data. Mixed data together with conditional data will provide better estimates of parameters than do mixed data alone. Our main objective is to obtain the optimal sample size for each bin of the mixed data to obtain conditional data, given approximate values of parameters and the distributional form of the mixture for the given data. We have also replaced the dependence of the function mix upon the optimizer nlm to optimizer optim to provide the limits to the parameters.

 Our purpose is to provide easily available tools to modeling fish growth using mixture distribution. However, it has a number of applications in other areas as well.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Roberts, L.E.
Psychology

abstract: Title: A New Grid Technique for Studying the Electrodermal Correlates of Conditioned Suppression in the Unrestrained Rat, Author: Susan Woll, Location: Thode

abstract:
Skin Conductance (SC) and Bar-pressing for a food
reward were examined throughout discriminative CER training
in two groups of rats. In one group of rats SC was
measured through a traditional grid electrodermal measurement
system. In the second group, the experimental group,
SC was measured between each grid bar successively and a
subdermal reference electrode, so that measurement artifacts
inherent in grid systems of measurement were either reduced
or eliminated in this group. Conditioned suppression of
bar-pressing was accompanied by a great increase in S.C. in
the experimental group. These results were attributed to
peripheral and central response mechanisms regulating
electrodermal activity.

abstract: Thesis

abstract: Master of Arts (MA)


title: Malliavin Calculus and Its Application in Finance

contributor:
Grasselli, Matheus
Mathematics

subject: Malliavin Calculus, application in finance, Monte Carlo simulation, Wiener Chaos theory

abstract: Page iii not included in the thesis and therefore, not included in the page count.

abstract:
 In recent years, some efficient methods have been developed for calculating derivative
price sensitivities, or the Greeks, using Monte Carlo simulation. However, the slow convergence, especially for discontinuous payoff functions, is well known for Monte Carlo simulation. In this project, we investigate the Malliavin calculus and its application in computation of the Greeks. Malliavin calculus and Wiener Chaos theory are introduced. The theoretical framework of the Malliavin weighted scheme of computation of the Greeks is explored in details, and the numerical implementation of the one-dimensional case and an example of the two-dimensional case are presented. Finally, the results are compared with those of finite difference scheme.

abstract: Thesis

abstract: Master of Science (MSc)


title: Implementation of Tabular Verification and Refinement

contributor:
Sekerinski, Emil
Computing and Software

subject: implementation, tabular verification, refinement, control system, tabular specification, visitor information system, axioms

abstract:
 It has been argued for some time that tabular representations of formal specifications can help in writing them, in understanding them, and in checking them. Recently it has been suggested that tabular representations also help in breaking down large verification and refinement conditions into a number of smaller ones.

 The article [32] developed the theory, but the real proof in terms of an implementation is not provided. This project is about formalizing tables in a theorem prover, Simplify, defining theorems of [32] in terms of functions written in the OCaml programming language, and conducting some case studies in verifying and refining realistic problems.

 A parser is designed to ease our job of inputting expressions. Pretty-print is also provided: all predicates and tables of the examples in our thesis are automatically generated.

 Our first example is a control system, a luxury sedan car seat. This example gives us an overall impression on how to prove correctness from tabular specification. The second example specifies a visitor information system. The design features of this example involve modeling properties and operations on sets, relations and functions by building self-defined axioms. The third example illustrates another control system, an elevator. Theorems of algorithmic refinements, stepwise data refinements, and the combination of algorithmic abstraction and data abstraction are applied correspondingly to different operations.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Janicki, Ryszard
Computer Science

abstract: Title: Formal Semantics for Tabular Expressions and Software Cost Reduction Method, Author: Imene Bourguiba, Location: Mills

abstract:
Unambiguous and precise software specification can not be achieved without some use of
formal notation. Table-based specification techniques are both readable and convenient.
They allow the representation of systems specifications in a very compact and yet precise
manner. They scale to software systems, and they may be easily used even by people unfamiliar
with the application domain. Additionally, the use of table-based notations makes
it relatively easy to check for such properties as consistency and completeness. Among
the table-based specification techniques discussed in the literature, the most popular are the
Software Cost Reduction (SCR) method and tabular expressions. Both of these techniques
are successfully used in practice to formally specify software requirements. The Software Cost Reduction (SCR) method is a formal method for specifying the
requirements of software systems that is based on tabular notation. SCR is used in a wide
range of applications. The second technique tabular expressions comprises a collection of cells, with each
cell holding a single expression. The beauty of tabular expressions stems from both their
visual structure and their concise representation of mathematical functions and relations.
As a result, these expressions are suitable for use in every software engineering phase, from
establishing requirements to completing final testing. To successfully be used in practice, the specification techniques chosen should be supported
by tools for creating, editing and transforming tables. Creating tools in the absence
of reasonable formal semantics often results in failure. Formal semantics are also needed
to compose and decompose tables in a modular way. Although SCR has been used in many projects and organizations to specify software requirements,
perhaps surprisingly, its semantics are not well defined. Specifically, the symbols
used in this method are ambiguous, especially those that serve to denote SCR events.
Further, the SCR method does not include either table composition or decomposition. The tabular expressions technique was also lacking, though in different ways than SCR.
A literature review revealed that the techniques applied to address the challenges inherent
in tabular expressions composition have their own limitations. The aim of this research, then, was to improve the semantics of both the SCR and the
tabular expressions specification methods. To this end, SCR tables were converted into
tabular expressions, as they have a rather precise semantics. Additionally, a new way to
model the SCR events with first order logic is presented. Finally, a simpler way to define
SCR events with propositional logic is proposed. By improving the semantics of the two specification methods, numerous advantages
are realized. These include increasing the readability of tables, and eliminating previously
ambiguous symbols. Moreover, improving the semantics enabled certain tasks to be carried out more easily,
such as facilitating the verification and validation process and improving the tool set supporting
the SCR method. In moving towards a richer semantics, this research allowed for
the introduction of algebra for tabular expressions, as well as operators for tables composition
and decomposition. Further, the research revealed the inherent power of tabular expressions.
This was accomplished by composing a regression to demonstrate where tabular
expressions get their power in specifying functions, relations and programs. An application
of tabular expressions for three dimensions and higher is successfully presented. Next, a
language and a structure for tabular expressions is proposed. Then, it is shown how tabular
expressions could be represented by a lattice and by a vector space, respectively. Finally,
the discussion considers the ways in which such an enhanced tabular expressions application
could also be applied to other fields, such as software engineering and computer
science.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Computations in Galois Cohomology and Hecke Algebras

contributor:
Sharifi, Romyar
Mathematics

subject: computations, Galois Cohomology, Hecke Algebras, nontrivial possibility, Bernoulli numbers, element

abstract:
 We study two objects: an ideal of a Hecke algebra, and a pairing in Galois cohomology.

 Let h be the Hecke algebra of cusp forms of weight 2, level n, and a fixed Dirichlet character modulo n generated by all Hecke operators, where n is an odd prime p or a product of two distinct odd primes N and p. We study the Eisenstein I ideal of h. We wrote a computer
program to test whether Up - 1 generates this ideal, where Up is the pth Hecke operator in h. We found many cases of n and the character so that Up - 1 alone generates I. On the other hand, we found one example with N = 3 and p = 331 where Up - 1 does not generate I.

 Let K = Q(μn) be the nth cyclotomic field. Let S be the set of primes above p in K, and let G_K,S be the Galois group of the maximal extension of K unramified outside S. We study a pairing on cyclotomic p-units that arises from the cup product on H1(G_K,S, μp). This pairing takes values in a Gal(K/Q)-eigenspace of the p-part of the class group of K. Sharifi has conjectured that this pairing is surjective. We studied this pairing in detail by imposing linear relations on the possible pairing values. We discovered many values of n and the character such that these relations single out a unique nontrivial possibility for the pairing, up to a possibly zero scalar.

 Sharifi showed in [S2] that, under an assumption on Bernoulli numbers, the element Up - 1 generates the Eisenstein ideal I if and only if pairing with the single element p is surjective. In particular, in the instances for which we found a unique nontrivial possibility for the pairing, then if Up - 1 generates I, we know that the scalar up to
which it is determined cannot be zero.

abstract: Thesis

abstract: Master of Science (MSc)