title: Molecular Dynamics Simulation of Irradiation Damage in α-Zirconium

contributor:
Yao, Zhongwen
Mechanical and Materials Engineering

subject:
Cascade
Irradiation
Molecular Dynamics
Zirconium

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2016-02-24 23:49:55.523

abstract:
Zirconium alloys, due to their good corrosion resistance and low neutron absorption
cross section, are widely used in heavy and light water nuclear reactors. Irradiation
induced defects and deformation lead to mechanical property degradation and potentially lead to accidents. In this study, molecular dynamics method, as a powerful
atomic-level simulation tool, is applied to investigate and characterize the formation
and evolution of point defects in irradiated alpha-zirconium by using a recent updated many-body interatomic potential. The effects of strain field on point defects,
the formation of dislocation loops and the effects of niobium in zirconium-niobium
system have been also explored. This dissertation has focused on understanding the
atomic-level mechanism of irradiation damages and defect formation in zirconium.

After a brief introduction in Chapter 1, Chapter 2 is the literature review including topics of displacement cascade, irradiation induced deformation, importance of
zirconium in nuclear reactors and possible simulation methods. Chapter 3 reports
a comparison of previous potential and current potential in a displacement cascade
simulation in alpha zirconium. In Chapter 4, the shape of irradiation cascades in alpha zirconium has been studied, and the threshold displacement energy in zirconium
has been calculated. Chapter 5 studies the strain effects (up to 1%) on defects in
zirconium. Chapter 6 extends the work in Chapter 5 with tensile strain up to 5%; a
void has been found in the displacement cascades in alpha zirconium under the applied strain field. In Chapter 7, simulations have been conducted to study the effects
of irradiation cascades in alpha zirconium within one vacancy type < a > loop. In
Chapter 8, other than most work in literature focused on alpha phase in zirconium alloy (hexagonal close-packed crystal structure), we have considered irradiation effects
on beta phase (body centered cubic structure) using MD calculations. The impact of
niobium in zirconium-niobium system is also studied. Chapter 9 contains a summary
of present thesis and possible future work. Appendixes in the end contain the basic
description of parallel programming, various methods of defect analysis, some related
input files and programs.

abstract: PhD


title: Characterization of hydrides and delayed hydride cracking in zirconium alloys

contributor:
Daymond, Mark R.
Mechanical and Materials Engineering

rights: Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada

rights: ProQuest PhD and Master's Theses International Dissemination Agreement

rights: Intellectual Property Guidelines at Queen's University

rights: This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.

subject: DHC Hydride

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2016-02-26 08:25:27.692

abstract: This thesis tries to fill some of the missing gaps in the study of zirconium hydrides with state-of-art experiments, cutting edge tomographical technique, and a novel numerical algorithm. A new hydriding procedure is proposed. The new anode material and solution combination overcomes many drawbacks of the AECL hydriding method and leads to superior hydriding result compared to the AECL hydriding procedure. The DHC crack growth velocity of as-received Excel alloy and Zr-2.5Nb alloy together with several different heat treated Excel alloy samples are measured. While it already known that the DHC crack growth velocity increases with the increase of base metal strength, the finding that the transverse plane is the weaker plane for fatigue crack growth despite having higher resistance to DHC crack growth was unexpected. The morphologies of hydrides in a coarse grained Zircally-2 sample have been studied using synchrotron x-ray’s at ESRF with a new technique called Diffraction Contrast Tomography that uses simultaneous collection of tomographic data and diffraction data to determine the crystallographic orientation of crystallites (grains) in 3D. It has been previously limited to light metals such as Al or Mg (due to the use of low energy x-rays). Here we show the first DCT measurements using high energy x-rays (60 keV), allowing measurements in zirconium. A new algorithm of a computationally efficient way to characterize distributions of hydrides - in particular their orientation and/or connectivity - has been proposed. It is a modification of the standard Hough transform, which is an extension of the Hough transform widely used in the line detection of EBSD patterns Finally, a basic model of hydrogen migration is built using ABAQUS, which is a mature finite element package with tested modeling modules of a variety of physical laws. The coupling of hydrogen diffusion, lattice expansion, matrix deformation and phase transformation is investigated under striation crack growth conditions. The result is a progress in applying diffusion of H and crack propagation within a commercial finite element package.

abstract: PhD


title: Diatoms as Bioindicators of Environmental Change in Cape Herschel and Pim Island (Nunavut, Canada) Ponds

contributor:
Smol, John P.
Biology

subject:
Paleolimnology
High Arctic
Cape Herschel
Diatoms

abstract: Thesis (Master, Biology) -- Queen's University, 2016-02-25 13:36:41.386

abstract: The High Arctic is especially sensitive to climatic change, but typically direct long-term monitoring data are lacking.  Instead, paleolimnological approaches are now widely used to reconstruct past environmental changes. In particular, sub-fossil diatoms are well-established paleo-indicators of past limnological conditions.  My thesis research is focused on Cape Herschel, east-central Ellesmere Island, as the numerous ponds in this region are well-studied and encompass a spectrum of morphometry, microclimate, and vegetation.  This thesis has two separate but related chapters. The first chapter documents recent limnological changes and associated epilithic and surface sediment diatom assemblages from five well-studied Cape Herschel ponds, sampled on a semi-regular basis from 1987-2011. Diatom trends were reconstructed and compared to a suite of water-chemistry variables. Increased species diversity in both epilithic and surface sediments were observed, indicative of warming and associated longer ice-free growing seasons, allowing for the establishment of taxa with more complex lifestyles. These ponds also experienced increases in conductivity, dissolved organic carbon, dissolved inorganic carbon, and pH over the sampling period. Trends in diatom assemblage were more pronounced in epilithic samples (representing year-to year changes), when compared to surface sediments (an integration of multiple years of diatom production). Diatom assemblages from the Cape Herschel ponds were then compared to previously studied and near-by (~10 km away) Pim Island ponds. The latter ponds had a more muted response to recent climate warming, likely due to their colder microclimates linked to their close proximity to near-shore sea ice. The second chapter focused on diatom assemblages from sediment cores recovered from two Pim Island ponds. Diatom assemblages in both sediment cores recorded a recent shift from low diversity benthic fragilarioids to more diverse assemblages dominated by epiphytic taxa, with more complex growth forms. This shift in taxa and diversity reflects a warming environment and longer growing season, but these long-term assemblage changes were more muted when compared to the warmer Cape Herschel ponds.  Taken together with previous studies, this research further demonstrates the sensitivity of diatoms to climatic changes.

abstract: M.Sc.


title: Microgrid Control Based on an Adaptive Notch Filter Power Processor

contributor:
Bakhshai, Alireza
Electrical and Computer Engineering

subject:
Adaptive Notch FIlter
Synchronization
Control
Microgrid

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2016-02-26 15:45:14.369

abstract:
Recent environmental policies and higher needs of energy have led to the huge growth in renewable sources consumptions. Consuming renewable energies however, is not always free of challenges. Many studies have been done to have a reliable integration and localization of the distributed sources, which have evolved into microgrid concept. These studies are mainly focused on microgrid’s occurrence prediction methods, control schemes and their undeniable part, grid synchronization techniques. The main goal of the studies is to help the microgrid and their distributed sources to ride through the short disturbances in grid-connected and islanded modes. Disturbances and unplanned changes that occur to a microgrid result in voltage and frequency fluctuations. These fluctuations could have destructive effects on power equipments. Therefore the existence of a robust and reliable controller and synchronizer is a must in microgrids.
In this thesis, the focus is on synchronization techniques and control systems. Among different synchronization techniques including PLL-based methods and frequency adaptive methods, the Adaptive Notch Filter (ANF) is selected to be studied in more details. A controller design consisting of an ANF is then proposed to fixate the voltage and frequency of the system while islanded and to ensure the power generation sufficiency. Another important and critical task of the proposed controller is to prepare the islanded microgrid for transitioning to the grid-connected mode. The Fast and accurate synchronization technique is selected and a fast responding control system is proposed to achieve a smooth transition between the two modes.
The ANF synchronization technique along with the proposed PLL-less control design are modeled in Simulink/MATLAB, which their performances in a system with disturbances and occurrences are evaluated. Balanced and unbalanced loads are added to the system and the connection between the microgrid and the grid is established. In this thesis the accuracy of the proposed control system in different conditions is examined and simulation results are presented. The results show that balanced three phase voltages at a fixed frequency are achieved, which also ensures a smooth transition between two modes.

abstract: M.A.Sc.


title: Long-term hydroclimatic change and interannual variability in water sources, Apex River (Iqaluit), Baffin Island, Nunavut

contributor:
Lamoureux, Scott F.
Lafrenière, Melissa
Geography

subject:
Stable Water Isotopes
Water Sources
Hydrology

abstract: Thesis (Master, Geography) -- Queen's University, 2016-02-29 09:18:24.898

abstract: The eastern Canadian Arctic is home to Canada’s largest Indigenous population, which depends on local freshwater sources for drinking water. However, small watersheds have rarely been analyzed for long-term hydrologic response to changing climate. This study aims to address this issue by examining the Apex River, a small watershed with a long hydroclimatic record, near Iqaluit, Nunavut. Particular emphasis was placed on the long-term changes in climate and river discharge, and the seasonal variability of water sources between two snapshots in time, 1983 and 2013. Long-term hydrological data were obtained from gauge station 10UH002, operated by Environment and Climate Change Canada, and long-term meteorological data were acquired from Environment Canada–operated stations near Iqaluit Airport. Breakpoint analysis suggested that long-term mean annual surface air temperatures have increased since 1994. In contrast, no long-term total precipitation or annual discharge changes were observed. However, river flow initiation and cessation analyses of the Apex River flow season indicates that flow extended into the autumn since the 2000s. The 2013 flow season lasted 44 days longer than the 1983 flow season. Systematic river sampling was undertaken throughout the 2013 thaw season to determine contributing proportions of event (snowmelt or rainfall) and pre-event (baseflow) water to river runoff. Results from the stable isotope hydrograph separation for 2013 were compared to findings for 1983. Snow was the main source of water to the river during the snowmelt period in 1983 and 2013, however baseflow was still an important contributor. Although there was high similarity of water sources early in the season in 1983 and 2013, the two years differed during the autumn. In 2013 there was a high rainfall runoff response that was not present in 1983, suggesting high release of late-season sub-surface water storage and an increased sensitivity to late-season rainfall events in 2013. This research provides insights into the hydrologic response of the Apex River to long-term climatic change, and highlights the need for high-quality precipitation and discharge data for effective long-term hydrological assessment.

abstract: M.Sc.


title: Containment of Organic Contaminants Using Geosynthetics

contributor:
Rowe, Kerry
Civil Engineering

subject:
Vapour Barrier
Diffusion
Geomembrane
Arctic
Antarctica
Polychlorinated Biphenyl
Compacted Clay Liner
BTEX
Geosynthetic Clay Liner

abstract: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2016-02-29 12:31:48.253

abstract:
The use of geosynthetics to contain volatile organic compounds (VOCs) and polychlorinated biphenyls (PCBs) in composite liner systems is evaluated through laboratory and field experiments. Diffusive parameters for benzene, toluene, ethylbenzene, and xylenes (BTEX) and PCBs through geomembranes are evaluated. Diffusion of BTEX is also evaluated through vapour barriers, as well as diffusion of PCBs through a compacted clay liner (CCL) and a GCL.
The permeation coefficient (Pg) for BTEX diffusion was lowest for high density polyethylene (HDPE) geomembrane, followed by chlorosulphonated polyethylene (CSPE), linear low density polyethylene (LLDPE), two ethylene interpolymer alloy (EIA) coated polyester products, four different PE based vapour barriers, and then polyvinyl chloride (PVC). In applications such as landfill covers or under-slab vapour barriers to mitigate VOC migration into buildings, these differences in Pg between products may have a significant effect on performance.
PCBs were found to have very high partitioning coefficients to HDPE geomembranes (Sgf = 150,000) and low Dg (1.0 × 10-14 m2/s), suggesting geomembranes can act as a sink to capture and store contaminants and not just as a diffusive barrier. In a typical municipal solid waste landfill (MSW) with good construction quality assurance (CQA), PCBs are unlikely to give rise to environmental concern. However, if CQA allows significant leakage, the environmental impacts from PCBs would need to be carefully evaluated on a case by case basis by modelling.
Containment using geosynthetics in remote Arctic environments for PCB contaminants is also evaluated. Geosynthetics are found to not have performance issues specific to climate, but instead with respect to subsurface angularity of soil, suggesting that normal design precautions should be maintained in polar environments. Evaluation of core samples exhumed from pond liners after nine years showed that with respect to PCBs, EIA geomembranes were similar to HDPE, with low Dg, and high Sgf.
Laboratory and field experiments were conducted to examine the hydration of GCL liners used to contain hydrocarbon-contaminated soil in Antarctica. Results indicate that hydration is achievable in Antarctica, but is heavily dependent on subsoil grain size and hydrology.

abstract: Some of the chapters remain unpublished at the moment.

abstract: PhD


title: White Gatekeeping and the Promise of Shelter: Confronting Colonial Logics within Women's Anti-Violence Services

contributor:
Morgensen, Scott Lauria
Gender Studies

subject:
Nonprofit Organizations
Indigenous Women
Decolonization
Violence Against Women
Women's Shelters

abstract: Thesis (Master, Gender Studies) -- Queen's University, 2016-03-01 12:19:22.039

abstract: In response to the recent surge in activism surrounding the missing and murdered indigenous women in Canada, the state has attempted to address colonial gender violence through strategies that involve the ongoing support and implementation of antiviolence services. While antiviolence agencies provide crucial short-term assistance to women in crises, indigenous women and two-spirited people have long questioned the ways in which these institutions exacerbate colonial gender violence by relying upon and strengthening apparatuses of state violence such as prisons, police and child protective services. In response to this problem I ask how white feminists invested in confronting colonial gender violence might begin to reform antiviolence service provision to help make indigenous women’s lives more liveable on both an individual and systemic scale. Answering this, I highlight the meaningful ways that indigenous women are addressing and alleviating violence through approaches that recognize the interconnectedness between all forms of violence indigenous people face. Contrasting these thoughtful and diverse approaches with those of mainstream antiviolence shelters exposes the colonial logics that continue to permeate white feminist antiviolence agencies. Speaking to white feminist women working within these institutions, I argue that white feminists working within the antiviolence sector must recognize their obligation to stand in solidarity with indigenous communities in their struggle against colonization. Providing ongoing support to indigenous struggles for decolonization provides a framework through which white feminists can begin to self-reflexively confront and undo their investments in whiteness, recognize and reform the aspects of service provision that uphold colonial logics, and support decolonization struggles that seek to eradicate all forms of violence against indigenous people.

abstract: M.A.


title: Exploring Principals' Perceptions, Beliefs, and Practices of Professional Development as Implemented through a Process of Collaborative Inquiry

contributor:
Lee, Elizabeth
Education

subject:
Thomas Guskey
Elementary Principals
Professional Development
Professional Learning
Collaborative Inquiry

abstract: Thesis (Master, Education) -- Queen's University, 2016-02-29 22:18:53.038

abstract:
This thesis reports on a qualitative methodological study that explored six principals’ descriptions of their perceptions, beliefs, and practices of professional development as implemented through a process of collaborative inquiry. Collaborative inquiry is commonly referred to within the educational literature, and is one form of professional development for educators. While plentiful, the literature presents ambiguous descriptions of professional development, resulting in a range of models being implemented with limited findings representing what does and does not work.
Participants were purposefully recruited and selected through a first-come first-serve approach using the elementary principal listserv of the participating school board located in Eastern Ontario. Two groups of principals were selected to participate; two who worked at Ontario Focused Intervention Partnership (OFIP) schools, identified by the Ontario Ministry of Education (OME) as having exceptional student learning needs, and four who worked at non-OFIP schools. Individual interviews and principals’ professional development documents provided the data explored in this research study. The data analysis incorporated the following strategies: (a) unique case orientation; (b) inductive analysis; (c) voice, perspective, and reflexivity; and (d) context sensitivity. The emerging themes from this analysis were: (1) building teacher motivation; (2) supporting teacher learning toward improved and consistent practices; and (3) promoting accountability amongst principals in promotion of collaborative inquiry. These themes were then connected to relevant research and OME literature and mapped onto Guskey’s (2000) evaluation of effective professional development framework. Recommendations for the future implementation of collaborative inquiry as a model of professional development included bringing a more balanced approach to equally emphasize applied teacher learning to coincide with the focus on teacher motivation. This thesis study voices the perceptions, beliefs, and experiences of principals currently using a collaborative inquiry model in the delivery of professional development. In doing so, this research may provide principals, school boards, and provincial stakeholders with authentic descriptions of what works and does not work in an effort to improve the delivery and application of professional development within schools and school boards.

abstract: M.Ed.


title: How Static Media is Understood and Used by High School Science Teachers

contributor:
Myers, Marie J.
Education

subject:
Pictures
Textbooks
Static Media
Science Teaching

abstract: Thesis (Master, Education) -- Queen's University, 2016-03-10 12:47:01.508

abstract: The purpose of is study is to explore the role of static media in textbooks, defined as printed images and text (Mayer, 2001), and how these media are viewed and used by high school science teachers. Since textbooks appeared in the late 1800s, pictorial aids have been used in them to support the teacher’s work in the classroom (Giordano, 2003). The research on textbooks prior to the 1970s doesn’t present relevant work related to their curricular role, quality, or instructional design (Woodward, Elliott, and Nagel, 1988/2013). Since then there has been abundant research on the use of visual images in textbooks that has been approached from: (a) the text/image ratio (Evans, Watson, & Willows, 1987; Levin & Mayer, 1993; Mayer, 1993; Woodward, 1993), and (b) the instructional effectiveness of images (Woodward, 1993). The theoretical framework for this study comes from multimedia learning (Mayer, 2001), information design (Pettersson, 2002), and visual literacy (Moore & Dwyer, 1994). Data was collected through in-depth interviews of three high school science teachers and the graphic analyses of three textbooks used by them. The interview data were compared through an analytic model developed from the literature, and the graphic analyses were performed using Mayer’s multimedia learning principles (Mayer, 2001) and the Graphic Analysis Protocol (GAP) (Slough & McTigue, 2013). The conclusions of this study are: (1) pictures are specially useful for teaching science because science is a difficult subject to teach, (2) due this difficulty, pictures are very important to make the class dynamic and avoid students distraction, (3) static and dynamic media when used together can be more effective, (4) some specific type of graphics were found in the science textbooks used by the participants, in this case naturalistic drawings, stylized drawings, scale diagram, flow chart – cycle, flow chart – sequence, and hybrids, no photographs were found, (5) graphics can be related not only to the general text but specifically to the captions, (6) the textbooks analyzed had a balanced proportion of text and graphics, and (7) to facilitate the text-graphics relationship the spatial contiguity of both elements is key to their semantic integration.

abstract: M.Ed.


title: Student Experiences in Undergraduate Anatomy:  An Exploration of Inquiry Learning as an Authentic Experience

contributor:
Hill, Ann Marie
Education

subject:
inquiry-based learning
authentic learning
undergraduate education
anatomy education

abstract: Thesis (Ph.D, Education) -- Queen's University, 2016-03-14 18:47:09.305

abstract: Anatomy education is challenged to develop contemporary approaches to teaching and learning that move beyond factual recall to elicit from students meaningful and deep understandings of the discipline. Inquiry-based learning is one such pedagogy that involves students’ active and increasingly independent investigation of questions and problems that are of interest to them. Because inquiry-based learning aims to encourage learners to draw upon wider contexts for learning and emphasizes the development of skills that extend beyond the confines of the classroom, there is a potential that students’ experiences are authentic in nature. This study sought to explore undergraduate students’ experiences of an Inquiry Project for learning anatomy. The project’s aims were twofold. First, to document, describe, and explain the essence of students’ experiences of engagement throughout the Inquiry Project, and second, to explore students’ experiences as potentially reflective of authentic learning. A hermeneutic phenomenology and case study methodology was used to explore students’ experiences of an Inquiry Project within a second-year undergraduate anatomy course at a mid-sized university in Ontario, Canada. Students (18) and facilitators (3) were observed during group work sessions and inquiry presentations, curricular documents and students’ work were analyzed, and interviews were conducted. Data analysis sought to describe students’ experiences and as a result, common meaningful themes of groups’ and students’ engagement were characterized. These results were then further analyzed through a theoretical framework of authentic learning, informed mainly by the Theory of Authentic Learning. While confirmatory and novel connections between factors were found to reflect Authentic Learning, five qualities of Authentic Inquiry Learning emerged from analysis of the data to represent how students’ learning was neither solely authentic nor inquiry-based, but a hybrid of the two. Authentic Inquiry Learning in anatomy education is characterized as the construction of knowledge through a process of disciplined inquiry in a way that gets students engaged in authentic scientific inquiry that draws upon their identities as a way of making sense of and applying anatomical understandings.

abstract: PhD


title: Short and Long Term Behaviour of Externally Bonded Fibre Reinforced Polymer Laminates With Bio-Based Resins for Flexural Strengthening of Concrete Beams

contributor:
Fam, Amir Z.
Civil Engineering

subject:
Bio-Based Resins
CFRP
GFRP
Bond
Durability
Furfuryl Alcohol Resin
Epoxidized Pine Oil

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2016-03-18 16:36:51.941

abstract:
The use of bio-based resins in composites for construction is emerging as a way to reduce of embodied energy produced by a structural system. In this study, two types of bio-based resins were explored: an epoxidized pine oil resin blend (EP) and a furfuryl alcohol resin (FA) derived from corn cobs and sugar cane. Nine large-scale reinforced concrete beams strengthened using externally bonded carbon and glass fibre reinforced bio-based polymer (CFRP and GFRP) sheets were tested. The EP resin resulted in a comparable bond strength to conventional epoxy (E) when used in wet layup, with a 7% higher strength for CFRP. The FA resin, on the other hand, resulted in a very weak bond, likely due to concrete alkalinity affecting curing. However, when FA resin was used to produce prefabricated cured CFRP plates which were then bonded to concrete using conventional epoxy paste, it showed an excellent bond strength. The beams achieved an increase in peak load ranging from 18-54% and a 9-46% increase in yielding load, depending on the number of FRP layers and type of fibres and resin.
Additionally, 137 concrete prisms with a mid-span half-depth saw cut were used to test CFRP bond durability, and 195 CFRP coupons were used to examine tensile strength durability. Specimens were conditioned in a 3.5% saline solution at 23, 40 or 50oC, for up to 240 days. Reductions in bond strength did not exceed 15%. Bond failure of EP was adhesive with traces of cement paste on CFRP, whereas that of FA was cohesive with a thicker layer of concrete on CFRP, suggesting that the bond between FA and epoxy paste is excellent. EP tension coupons had similar strength and modulus to E resin, whereas FA coupons had a 9% lower strength and 14% higher modulus. After 240 days of exposure, maximum reductions in tensile strength were 8, 19 and 10% for EP, FA and E resins, respectively. Analysis of Variance (ANOVA) was also performed to
iii
assess the significance of the reductions observed. High degrees of variability in the test results may have skewed the results from this statistical analysis.

abstract: M.A.Sc.


title: Radio Resource Allocation for Device-to-Device Communications Underlaying Cellular Networks

contributor:
Akl, Selim
Taha, Abd-Elhamid M.
Computing

subject:
device-to-device communication
resource allocation
Cellular network
Communication network

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2016-03-21 11:01:14.331

abstract:
Inexpensive connectivity and computing power have caused the number of communicating devices to explode in the last decade. New applications are emerging every day to take advantage of the proximity and abundance of these devices. Device-to-Device (D2D) communication using cellular spectrum to increase spectral efficiency of the network is a technology component of Long Term Evolution-Advanced (LTE-A). In D2D communication underlaying cellular networks, devices communicate with each other using a direct link using cellular resources without going through the evolved Node B (eNB) but remaining under the control of it. D2D communication
is expected to be one of the prominent features supported by future cellular networks because of reusing the cellular spectrum to increase the system performance of cellular networks. However, due to the limitations of a licensed spectrum when these devices share a cellular spectrum to communicate directly among themselves, the same resource may need to be shared among cellular and D2D communicating pairs. This resource sharing introduces a new interference scenario, which needs to be coordinated through a new resource allocation scheme.
We investigate this problem of interference coordination and explore three different perspectives from which this problem can be viewed, namely a) interference minimization; b) fair allocation while minimizing interference; c) Quality of Service (QoS) satisfaction while maximizing total system sum rate of the cellular network. We show that the proposed schemes are suitable for the short LTE scheduling period of 1 ms as they are computationally tractable. Our schemes can allocate radio resources to D2D pairs underlaying a cellular network in a short time, ensuring fairness in allocation while minimizing interference, and increasing the total system sum rate
of the network while maintaining a QoS target.

abstract: PhD


title: Electromagnetic tracking in ultrasound-guided high dose rate prostate brachytherapy

contributor:
Akl, Selim
Fichtinger, Gabor
Computing

subject:
Electromagnetic tracking
High-dose-rate prostate brachytherapy

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2016-03-22 11:20:08.356

abstract:
Electromagnetic (EM) tracking assistance for ultrasound-guided high-dose-rate (HDR) prostate brachytherapy has recently been introduced in order to enable prompt and uncomplicated reconstruction of catheter paths with respect to the prostate gland. However, EM tracking within a clinical setting is notorious for fluctuating measurement performance. In fact, measurements are prone to errors due to field distortions caused by magnetic and conductive objects and can compromise the outcome of the procedure. Enhancing these measurements is therefore paramount.

The objective of this thesis is to enable robust and accurate reconstructions of HDR catheter paths on the ultrasound images of the prostate gland using EM tracking. To achieve this objective, the measurement uncertainty of an electromagnetic system was first characterized in various environments; this characterization enabled us to identify optimum setup configurations and model the measurement uncertainty. Second, we designed and implemented a specialized filtering method for catheter path reconstructions, combining the nonholonomic motion constraints which apply to the EM sensor, with both the position and orientation measurements of the sensor. Finally, ultrasound scan planes were robustly tracked with the help of a simultaneous localization and calibration algorithm; this method allows for dynamic tracking of the ultrasound probe while simultaneously mapping and compensating for the EM field distortions.

We experimentally validated the performance of our advanced filter for catheter path reconstructions in a HDR brachytherapy suite; the EM sensor was threaded within paths of various curvatures at several insertion speeds. The simultaneous ultrasound probe tracking and EM field distortion compensation approach was also assessed in the brachytherapy suite. The performances of our approaches were compared to conventional error minimization methods. The advanced methods effectively increased the EM tracking accuracy of catheter paths and ultrasound probes. With the help of our proposed approaches, EM tracking can provide effective assistance for a plurality of clinical applications.

abstract: PhD


title: Binding characterization of sulfonamide antibiotics and polycyclic aromatic hydrocarbons to micelles using semi-equilibrium dialysis (SED) and 1H NMR spectroscopy

contributor:
Brown, R. Stephen
Chemistry

subject:
Semi-equilibrium dialysis
Binding constant

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2016-03-29 17:53:46.735

abstract: Micellar enhanced ultrafiltration (MEUF) has been shown to be an effective removal technique for a variety of trace contaminants in wastewater, especially for low molecular weight organic contaminants. In MEUF, contaminants first partition into surfactant micelles prior to removal by ultrafiltration, where the contaminants are below the molecular weight cut-off of the ultrafiltration membrane but the micelles are above the cut-off. To predict the removal efficiency of MEUF, it is important to measure of extent to which a species will bind to a micelle as well as to develop an understanding of the dynamics of the binding interactions.  Herein, we report micellar binding constants for a series of sulfonamide antibiotics (sulfadoxine, sulfathiazole, sulfamethoxazole, sulfamerazine, sulfadiazine, sulfamethazine, sulfacetamide, sulfaguanidine, and sulfanilamide) with CTABr micelles, as determined using semi-equilibrium dialysis and 1H NMR methods. We also report the binding constant measurements for polycyclic aromatic hydrocarbons (PAHs), including phenanthrene, naphthalene, pyrene and fluorene, to several micelle types. Unlike the antibiotics, where charge-charge interactions determined binding to CTABr micelles, the neutral PAHs show strong binding with micelles because of hydrophobic interactions. Our results enabled us to develop a relationship between binding constant (Log KB) and Log KOW for both charged and neutral compounds, which will be useful for predicting MEUF performance for removal of organic micro contaminants from wastewater.

abstract: PhD


title: Nursing Students and Patient Safety:  Errors, Curriculum, and Perspectives

contributor:
Godfrey, Christina
Medves, Jennifer M.
Nursing

subject:
nursing education, nursing students
patient safety

abstract: Thesis (Ph.D, Nursing) -- Queen's University, 2016-03-29 14:35:39.106

abstract:
Healthcare is a high reliability industry designed to improve, preserve, and protect the health of citizens (Institute of Medicine [IOM], 2000).  Events that affect patient safety have been reported with increasing regularity since the emphasis on patient safety in the early 2000’s (IOM).  Nursing care significantly affects patient outcomes.  The IOM mandated transformation of health education to incorporate patient safety concepts in the United States and this has gradually influenced health education globally (2003).  Nursing education programs are designed to increase students’ knowledge, skills, and attitudes (KSAs) and students’ confidence levels are indicators of their KSAs.  Gaining insight into what errors students are making will reveal where KSAs are weak and where educational transformation may be required.  Although teaching patient safety concepts is important, studies exploring this are limited.  Research exploring patient safety content in nursing curricula in Ontario could not be found in the existing literature.
 		This study found that the greatest number of nursing student errors reported in the literature are linked to medication administration followed by errors related to the environment, equipment, and devices (Raymond, Godfrey, & Medves, 2016a).  Despite medication administration errors occurring the most often, students expressed the greatest confidence in this area and it seemed to be the most abundantly integrated in the written curriculum.  After reviewing three nursing curricula, it was noted that patient safety content was incorporated within each of the reviewed programs to a different degree (Raymond et al., 2016b).  Students are more confident on patient safety topics in the classroom than in the clinical settings and there were no educationally significant differences noted between baccalaureate and practical nursing students’ confidence levels.  Although both baccalaureate and practical nursing students fear repercussions when making an error, a greater percentage of practical nursing students expressed this concern (Raymond et al., 2016c; 2016d).  Higher percentages of practical than baccalaureate nursing students felt errors were addressed as individual mistakes instead of system issues (Raymond et al., 2016c, 2016d).  This research suggests that further initiatives aimed at reducing students’ fears while focusing on errors as system issues within both classroom and clinical settings are needed.

abstract: PhD


title: Caribbean Immigrants in Relationship: Tracing the Transnational Connections between Austin Clarke and Samuel Selvon

contributor:
Bongie, Christopher
English

subject:
Austin Clarke
Samuel Selvon
Caribbean Immigrants
Caribbean Literature

abstract: Thesis (Ph.D, English) -- Queen's University, 2016-03-29 16:16:09.861

abstract:
Austin Clarke and Samuel Selvon are similarly positioned in the literary field and offer overlapping perspectives in their depictions of Caribbean immigrants, yet for the most part, there has been no in-depth comparison of their careers. Moreover, their decades-long friendship and its documentation—archived correspondence and Clarke’s memoir dedicated to Selvon’s memory—have never garnered critical attention. My dissertation fills this gap in criticism through an investigation of the transnational relationships surrounding and explored within their literary production. In situating these two authors as simultaneously connected and isolated as they traverse different national boundaries, I foreground their emphasis on the interplay between the interpersonal relationships of Caribbean immigrants and the social structures within which they function. Drawing on the work of Pierre Bourdieu, I argue that both Clarke and Selvon investigate how social reality is encoded, inscribed, and naturalized while also suggesting the transformative potential of the social practices of Caribbean immigrants.
Underlying this dissertation is a reflective reconsideration of the categories used to organize Caribbean writers and the interpretive frames applied to their literary production. Through reference to their archived correspondence, I explore the parodic strategies deployed by Clarke and Selvon as they conform to and undermine established boundaries, categories, and modes of behavior. My careful study of the privileges and pressures of macho performance in their correspondence guides my reading of their fiction and my refashioning of their critical reputations. Though critics have read their work as simply sociological descriptions of distinct social contexts and have misrepresented them as inept or reductive when it comes to issues of gender and sexuality, I demonstrate that both authors present remarkably nuanced depictions of gender construction as informed by and informing racial tensions, economic realities, and sociopolitical contexts. Clarke and Selvon demystify naturalized systems of domination, and careful analysis of the relationships that shape the lives of their characters uncovers how their practices and perceptions are tied to their manufactured feelings of loneliness and vulnerability as they desperately seek control of or become resigned to their constrained circumstances.

abstract: I am planning to turn this dissertation into a book manuscript, so I do not want it to be immediately available on the web.

abstract: PhD


title: Consciousness:  How its Subjectivity is  Compatible with Physicalism

contributor:
Mercier, Adele
Philosophy

subject:
Physicalism
Subjectivity of Consciousness
Consciousness
Philosophy of Mind

abstract: Thesis (Ph.D, Philosophy) -- Queen's University, 2016-03-29 22:08:13.093

abstract:
Though our everyday life is made up of contacts with the world through conscious experiences, our understanding of this basic fact is limited. Consciousness and the “hard problem” have been one of the most controversial subjects in contemporary philosophy of mind.
This thesis argues for a physicalist approach to conscious experience, accepting the idea, widely accepted in contemporary philosophy of mind, that phenomenal consciousness and its qualitative aspects resist functionalization. They are not explainable and knowable merely through functional explanation, giving rise to an explanatory and epistemic gap between phenomenal and scientific knowledge. While affirming the existence of an epistemic gap, this thesis attempts to explain it and to deny its presumed ontological implications.
I discuss here two major physicalist theories (the Phenomenal Concept Strategy and Higher-Order Theories), as well as two main anti-physicalists arguments (Jackson’s knowledge argument and Chalmers’ zombie argument). I argue that the consciousness property, being an emergent as opposed to a supervenient property, is an ontologically physical property. I also argue that the unique feature of consciousness, i.e. its subjectivity, is an epistemological relation between a subject, as an experiencer, and her own physical phenomenal properties. I show how the subjectivity of consciousness is compatible with physicalism.

abstract: I need to protect rights for publication.

abstract: PhD


title: Soliton-Like LT Codes over GF(4) and GF(8)

contributor:
Yousefi, Shahram
Electrical and Computer Engineering

subject:
telecomunications
fountain codes
coding
rateless
LT codes
non-binary

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2016-03-30 16:12:01.504

abstract:
The Luby Transform (LT) codes are the first practical realization of fountain codes. LT codes were designed for efficient use over erasure channels. However, the degree distributions designed for the Binary Erasure Channel (BEC), such as the Robust Soliton Distribution (RSD) which are asymptotically and universally optimal over the BEC, are not optimal over noisy channels.

Research has been done to improve performance over noisy channels and in finite length codes by changing the degree distribution or information sampling method. Many distributions that performed better than the RSD still shared some of its properties. These distributions fit under the umbrella of soliton-like distributions.

In this work, we consider using non-binary LT codes to improve the Bit Error Rate (BER) and realized rate of the system with an acceptable increase in complexity.  While testing different degree distributions on 4-ary and 8-ary LT code, the RSD was not performing well. This led to the design of the fundamental degree distribution (FDD), which falls under the category of soliton-like distributions. The parameters for this distribution are found through Monte Carlo numerical optimization.  This new degree distribution was able to show improvements when moving to higher order fields in terms of BER and realized rate.

It is clear that there is added complexity when moving to higher order fields. Some of this complexity is removed in this work by performing no multiplications over the field at intermediate nodes, as it was shown to provide negligible gains.

As well, we look at shaping the left degree distribution (LDD) to further increase the improvements in the non-binary applications. We show that by strategically connecting the encoded symbols to the input symbols with the lowest degree, we can see improvements in the BER and realized rate of 4-ary LT codes. The realized rate increases from around 0.75 to 0.85 at an SNR per bit of 16 dB, simply by shaping the LDD for our non-systematic short length codes, with k = 100 at a negligible added complexity.

abstract: M.A.Sc.


title: Adaptive Resistance Control Solutions in an Assisted Coding Environment

contributor:
Liu, Yan-Fei
Electrical and Computer Engineering

subject:
Cost of Harvest
Voltage Controlled Attenuator
Linear Regulator
Energy Harvesting
Embedded Coder
MATLAB
Boost Converter
Simulink
PFC
Backpack

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2016-03-31 10:22:38.556

abstract:
This thesis focuses on the implementation of a human energy harvester’s resistance control scheme for a full capacitance boost converter, low capacitance boost converter, and a voltage controlled attenuator. The boost converter control schemes utilize an adapted PFC ACMC boost converter topology with input resistance as a controlled feedback variable for the current loop, while disregarding the output voltage resistance. The electronic module’s power draw affects the applied resistance felt by the user. The prototype outputs a nominal 10W of power for the emulated 2.5Ω full load. Previous research has enabled constant resistance, threshold resistance, and variable resistance control implementations on a boost converter coded in Code Composer Studio’s C/C++ environment.
The first goal of this thesis sought to eliminate or minimize the necessary C/C++ coding required for resistive control. This was achieved through the implementation of MATLAB Simulink’s Embedded Coder’s C2000 Library coding environment, using a block diagram control scheme with integrated MATLAB coding.
Three control schemes are proposed: Ramp and Hold, Optimized Resistance, and Power Regulation control algorithms.  The Ramp and Hold scheme targets the decoupling point between the motor and the input encoder. The control method increases from light to full load peaking and holding the full load condition at this decoupling point to target the energy harvester’s negative work period.  The Optimized Resistance algorithm averages the user’s average voltage at light load, and then increments the resistance until this voltage begins to drop, indicating a change in the user’s kinematics.  The Power Regulation control scheme programs a required average output power per step for the user, and dynamically alters the resistance felt by the user to achieve this goal.
The final boost converter had a peak efficiency DC of 93.4% for 25W input power at Vin=20V and Rin=15Ω. The linear regulator voltage controlled attenuator acts as a simple resistive load to dissipate the entire 10W input power, using the low side MOSFET for power dissipation. The three control schemes were implemented and tested on a boost converter with a 2200µF, 940µF, and 47µF output capacitor. Integrated improvements to the system and future work are then proposed.

abstract: M.A.Sc.


title: Distributed control of multi-agent systems using extremum seeking

contributor:
Guay, Martin
Chemical Engineering

subject:
Multi-agent systems
Distributed control
Extremum seeking control
Distributed optimization

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2016-03-31 12:05:41.082

abstract:
A model free control technique (extremum seeking) is employed to address problems of large-scale systems involving multi-agents in real-time. This thesis focuses on the use of extremum seeking control in a distributed, coordinated and a cooperative fashion to solve distributed control and optimization problems.
First, the problem of maximizing the power produced in a wind farm is considered. To tackle this problem, a distributed time-varying extremum seeking control (TVESC) technique is employed to overcome the need to provide accurate models of aerodynamic wake interactions among the wind turbines. Solutions in continuous-time and discrete-time are presented.
Secondly, precise knowledge of the structure of network connectivity has been utilized in solving cooperative optimization problems of multi-agent systems to achieve global objectives. In this thesis, a distributed proportional-integral extremum seeking control technique is designed to tackle such problems over unknown networks.

abstract: M.A.Sc.


title: Nonlinear Response of Unbiased and Biased Bilayer Graphene at Terahertz Frequencies

subject: Bilayer Graphene

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2016-03-31 12:37:39.85

abstract:
The main focus of this thesis is the investigation of the nonlinear response of unbiased and biased bilayer graphene to incident radiation at terahertz frequencies. We present a tight-binding model of biased and unbiased bilayer graphene that is used to calculate the nonlinear terahertz response. Dynamic equations are developed for the electron density matrix within the length gauge. These equations facilitate the calculation of interband and intraband carrier dynamics. We then obtain nonlinear transmitted and reflected terahertz fields using the calculated nonlinear interband and intraband current densities.

We examine the nonlinear response of unbiased bilayer graphene as a function of the incident field amplitude. In this case the sample is taken to be undoped. In the reflected field, we find the maximum third harmonic amplitude to be approximately 30\% of the fundamental frequency for an incident field of 1.5 kV cm$^{-1}$, which is greater than that found in undoped monolayer graphene at the same field amplitude.

To examine the nonlinear response of biased bilayer graphene, we investigate two different scenarios. In the first scenario, we consider an undoped sample at fixed temperature. We find that when the external bias has a value of 2 meV, the generated third harmonic in the reflected field is approximately 45\% of the fundamental for an incident field amplitude of 2 kV cm$^{-1}$. When we increase the external bias further to 8 meV, we find the generated third harmonic field is approximately 38\% of the fundamental for an incident field amplitude of 1 kV cm$^{-1}$. For both of these bias values, the generated third harmonic is greater than that found in undoped monolayer graphene. In that system, the generated third harmonic field is approximately 32\% of the fundamental for an incident field amplitude of 200 V cm$^{-1}$

In the second scenario, we consider doped biased bilayer graphene. We fix the carrier density at 2$\times$10$^{12}$ cm$^{-2}$, the incident field amplitude at 50 kV cm$^{-1}$, and examine the response as a function of the external bias. We find the largest third harmonic amplitude is approximately 8\% of the fundamental for a bias of 0 meV (zero bias).

abstract: M.Sc.


title: Continuous and Digital Approaches to Manipulation and Detection of Analytes on Microfluidic  Devices

contributor:
Oleschuk, Richard
Chemistry

subject:
Microfluidics
Magnetic Actuation
EWOD
Digital Microfluidics

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2016-04-04 15:16:40.287

abstract:
Microfluidic devices are extremely popular in the area of analytical research as they reduce sample input requirements, have low operational cost, fast analysis time, high separation resolution and low detection limits.  A multitude of analytical techniques has been adapted to the microdevice format, including pre-treatment, separation, and detection. Depending on how the fluid is addressed and manipulated, microfluidics can be sub-divided into the “continuous-flow” and digital microfluidics (DMF) approaches. This thesis aims to demonstrate the versatility of microfluidic field of research, where a number of actuation approaches, fabrication methods and materials, on-chip operations and applications were explored.
“Continuous-flow” microfluidics allows manipulating the bulk of the sample through the narrow channels under the applied force. Fabrication techniques unique to thermoplastics were utilized to fabricate a “continuous-flow” device capable of separating small drugs and large biological molecules, where a microstructured fibre served as an electrospray ionization mass spectrometry (ESI-MS) emitter.
Interest in DMF, where discrete droplets are addressed and manipulated independently, has grown rapidly due to the versatility that arises from non-linear control of fluids. The most common approaches to droplet manipulation are based on either electrowetting-on-dielectric (EWOD) or magnetic interactions. EWOD devices were fabricated with standard photolithography procedures, where coatings with varying degrees of hydrophobicity were explored for EWOD actuation – natural leaf surface, Teflon® AF, and a series of fluorinated silica nanoparticle-based materials.
The magnetic actuation approach is based on the interaction of an external magnetic field and magnetically susceptible material inside the droplet, which can be transported over a low-friction surface. Natural superhydrophobic leaf, hydrophobic Teflon, and a commercial superhydrophobic surface were compared for their suitability for the particle-based magnetic actuation. We demonstrated that a commercial coating has excellent compatibility with magnetic actuation, where high actuation speed was reproducibly achieved.
We also developed a novel “particle-free” method of magnetic manipulation, where instead of magnetic particles, droplets contained paramagnetic salts with high magnetic susceptibilities were used. Droplets of five paramagnetic salts were efficiently actuated over the commercial superhydrophobic surface, where salts with higher magnetic susceptibility required lower concentrations and achieved higher actuation speed.  The “particle-free” approach was used with online fluorescence detection of an anti-cancer drug.

abstract: PhD


title: Wrist Motion Simulation With a Rigid Body Spring Model Comparing Different Elements Modeling Approaches

contributor:
Sellens, Rick
Mechanical and Materials Engineering

subject:
Carpal
Dynamic
Simulations
Wrist
Kinematics
Rigid Body Spring Model

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2016-04-08 13:02:01.041

abstract:
A rigid body spring model was used to simulate wrist motions. The carpal bones were constructed based on a computed tomography of a cadaver wrist. Bony structures were assembled as a wrist model in the simulation software, RecurDyn. Articulations between wrist joint bones were modeled using gliding surfaces, each was attached to its bone surface and this articulation was controlled by contact forces in the simulation software. Wrist ligaments were modeled by either one or two spring elements for each ligament or major component. Muscles of the wrist were represented by axial force elements. The force exerted by each tendon in each wrist movement was computed using either exponential function or sigmoid function in two different models. Each of these force functions were proportional to the distance between the simulation capitate and the capitate in the desired position. Capitate was chosen as tracking marker because the common center of rotation of wrist is within the capitate head.
Each of these approaches were simulated alone or with addition of a time factor. Eight wrist models were created. Each model simulated 34° extension, 57° extension, 30° flexion, 65° flexion, radial deviation and ulnar deviation. The root mean square error was calculated for linear and angular position for each carpal bone, each wrist movement, and for each model. The combined overall RMS errors for each model were calculated. The double spring ligament model with sigmoid force function considering time factor showed the least overall RMS error and most joint stability. The single spring ligament model with exponential force function without the time factor showed the highest RMS error and joint instability in some wrist motion simulations. The different modeling approaches used in this study helped in understanding the kinematics of the wrist joint and the wrist ligaments and tendons.
The results of this work encourage using these models for further kinematic studies in tandem with in vivo or in vitro studies for further validation. These models can be helpful in simulating non-physiological conditions of the wrist. Further work related to result validation using data from multiple wrists, further enhancements of ligaments and muscles modeling will improve the accuracy of these wrist models.

abstract: M.A.Sc.


title: Decision Criterion for Observation-Based Relays in LTE Networks

contributor:
Gazor, Saeed
Electrical and Computer Engineering

subject: LTE Relay

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2016-04-08 10:47:17.31

abstract:
Relay technology has the potential to dramatically improve throughput for Long Term Evolution (LTE) network users. However, the existing 3rd Generation Partnership Project (3GPP) standard for relaying, the Type 1 relay, is best suited to cell extension. An alternative design, Type 2, was considered for increasing throughput within the existing coverage region. It has not been standardized, but has been cited as in need of further study. In this thesis, we augment the Type 2 relay design and achieve the following:
1. Improve throughput for relay-supported users.
2. Empower the relays to make decisions as to which users they support.
3. Introduce as few new protocols as possible to implement the relay.
To achieve these objectives, the proposed relay has a decision criterion to compare its own achievable throughput against the throughput of any candidate users it detects. Depending on the relative quality of its connections, the relay may opt to provide two-hop Time-Division Multiplexing (TDM) support or retransmission support. Once it reaches its decision, the relay informs the evolved Node B (eNB) of its intent to support the user and the mode by which it will do so. The eNB adjusts its behaviour accordingly and continues to perform all downlink control functions. Unlike standard relay systems, the proposed approach requires no approval from the eNB and no user handoff.
Simulations were conducted using Network Simulator 3.21 (ns-3.21) and data was processed in MATLAB R2012a. For a relay with transmit power characteristics equivalent to users in the cell, 35% to 38% of users within its observation region are eligible for some form of support. The majority of supported users received retransmission support, rather than two-hop TDM. Additionally, if optimized relay placement can achieve a 5 dB improvement to the relay-eNB channel, the percentage of supported users increases to between 49% and 55%. With the 5 dB improvement, the number of users eligible for two-hop TDM increased substantially, particularly at larger bandwidths. Network configuration parameters had a considerable impact on results. In particular, the Control Format Indicator (CFI) and channel bandwidth (W) had the greatest impact on results.

abstract: M.A.Sc.


title: On the role of regularity in mathematical control theory

contributor:
Lewis, Andrew D.
Mathematics and Statistics

subject:
real analytic control system
regularity
Mathematical control theory

abstract: Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2016-04-08 11:57:25.987

abstract:
In this thesis, we develop a coherent framework for
studying time-varying vector fields of different regularity classes and their flows. This setting has the benefit of unifying all classes of regularity. In particular, it includes the real analytic regularity and provides us with tools and techniques for studying holomorphic extensions of real analytic vector fields. We show that under suitable integrability conditions, a time-varying real analytic vector field on a manifold
can be extended to a time-varying holomorphic vector field on a neighbourhood of that manifold. Moreover, in this setting, the nonlinear differential equation governing the flow of a
time-varying vector field can be considered as a linear
differential equation on an infinite dimensional locally convex vector space.  We show that, in the real analytic case, the integrability of the time-varying vector field ensures convergence of the sequence of Picard iterations for this linear differential equation, giving us a series representation for the flow of a time-varying real analytic vector field.

Using the framework we develop in this thesis, we study a parametization-independent model in
control theory called tautological control system. In the
tautological control system setting, instead of defining a
control system as a parametrized family of vector fields on a
manifold, it is considered as a subpresheaf of the sheaf of vector fields on that manifold. This removes the explicit dependence of the systems on the control parameter and gives us a suitable framework for studying regularity
of control systems. We also study the relationship between tautological control systems and classical control systems. Moreover, we introduce a suitable notion of
trajectory for tautological control systems.

Finally, we generalize the orbit theorem of Sussmann and Stefan to the tautological framework. In particular, we show that orbits of a tautological control system are immersed submanifolds of the state manifold. It turns out that the presheaf structure on the family of vector fields of a system plays an important role in characterizing the tangent space to the orbits of the system. In particular, we prove that, for globally defined real analytic tautological control systems, every tangent space to the orbits of the system is generated by the Lie brackets of the vector fields of the system.

abstract: PhD


title: In Vitro Assessment of Bone and Cartilage Stimulating Peptides

contributor:
Amsden, Brian
Chemical Engineering

subject:
in vitro assessment
bone regeneration
fracture healing
stimulating peptides
spinal fusion

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2016-04-08 15:46:36.55

abstract: Spinal fusion is an effective and one of the most commonly used surgeries to treat intervertebral disc degeneration (IDD) related low back pain. However, non-fusion still occurs in about 10-15% of the clinical cases. The global objective of this project is to develop a synthetic bone graft for the spinal fusion, combined with bone growth enhancing factors named bone and cartilage stimulating peptides (BCSP®). The focus of this present study is to assess BCSPs’ performance in various concentrations with respect to their effects on osteoprogenitor proliferation, osteogenic differentiation, cell culture mineralization and cell migration. BCSPs appeared to enhance the bone growth in the previous study using an animal model; however, the cellular and molecular mechanisms of BCSPs performance remain unclear. In this study, we examined three BCSPs in vitro with respect to their ability to enhance proliferation, to induce early osteogenic differentiation and mineralization, and to simulate the migration of osteoprogenitor cells. The proliferation, early differentiation, mineralization and migration assessments were carried out with a double-stranded DNA quantification, an alkaline phosphatase (ALP, early osteogenic differentiation marker) expression assay, an Alizarin Red S staining assay and a Boyden Chamber assay, respectively. Osteoprogenitor cells examined included MC3T3-E1 preosteoblasts, human bone marrow-derived mesenchymal stem cells (hBM-MSCs), human periosteum-derived stem cells (hPDSCs), and rabbit periosteum-derived stem cells (rPDSCs). Both hBM-MSCs and MC3T3-E1 preosteoblasts exhibited a significant increase of ALP expression after the exposure to BCSP1 and BCSP7, and MC3T3-E1 preosteoblasts also exhibited a significant increase of ALP expression after the exposure to BCSP11. However, no significant difference was observed in proliferation, migration or mineralization assessments for any of the examined osteoprogenitor cells after exposure to BCSPs. The present work showed that BCSPs have a stimulating effect on the early differentiation of MC3T3-E1 preosoteblast and human BM-MSCs. However, BCSPs did not show any stimulating effects on the proliferation, mineralization and migration of osteoprogenitors listed, indicating that promoting early differentiation of osteoprogenitors might be one of the mechanisms of BCSPs’ in vivo bone growth stimulating effect.

abstract: M.A.Sc.


title: The Canadian Carceral State: Violent Colonial Logics of Indigenous Dispossession

contributor:
McKittrick, Katherine
Gender Studies

subject:
Indigenous Studies
Black Studies
Feminist Studies
Prison and Carceral Studies

abstract: Thesis (Master, Gender Studies) -- Queen's University, 2016-04-10 18:15:55.725

abstract: This thesis examines the over-representation of indigenous women in Canadian federal prisons. I situate the prison as a site of modernity to draw attention to the ways that the prison is underpinned by the logics of white supremacy. I posit that the prison is a complicated geography wherein the differential and overlapping colonial histories of slavery and indigenous genocide are intricately linked and also bifurcated. The prison enables racial violence and at the same time, erases this violence against indigenous women from public purview. This is to say, that the prison upholds the project of modernity through the sequestering and dispossession of indigenous communities, and this spatial act must be considered alongside other geographies of removal, such as the plantation and the reserve. Colonial carceral logics also operate beyond the space of the prison, which leads me to consider the staggering numbers of murdered and missing indigenous women as part of the colonial project that is deeply invested in the maintenance of white supremacy. In addition to reviewing key theories in black and indigenous prison studies, I discuss reports released from the Correctional Investigator’s Office to clarify how reportage narratives of “change” are unable to rectify the disproportionate rates of federally incarcerated indigenous women. I also explore maps of Canadian prisons to think through how colonial and carceral geographies conceal racial violence. Throughout this project, I centralize that within colonial spaces there are always decolonial narratives. I posit that prison abolition must be accompanied by decolonial projects invested in dismantling the logics of white supremacy. Specifically, turning to creative texts, such as storytelling, illuminates how practices of human relationality are subversive acts wherein articulations of a better future emerge.

abstract: M.A.


title: Occupation, Homelessness, and the Transition to Becoming Housed Among Chronically Homeless Persons

contributor:
Lysaght, Rosemary
Rehabilitation Science

rights: Creative Commons - Attribution-Non-commercial-No Derivate Works - CC BY-NC-ND

subject:
Meaningful Activity
Chronic Homelessness
Homeless Persons
Poverty
Social Determinants of Health
Activities of Daily Living

abstract: Thesis (Ph.D, Rehabilitation Science) -- Queen's University, 2016-04-12 16:49:30.162

abstract: Background: Existing homelessness research focuses on psychological and social aspects of this experience. There is limited literature focusing on the daily occupations of those who are chronically homeless, and particularly during the transition to becoming housed. Purpose: This research was carried out in 3 Phases. Phase I aimed to synthesize the current literature contributing to an understanding of occupational transition during the process of becoming housed among homeless persons. Phase II aimed to develop an understanding of the experience of occupational engagement of chronically homeless persons in a medium-sized city in Ontario, Canada. Phase III aimed to develop an enhanced understanding of the experience of occupational engagement of chronically homeless persons as they made the transition to becoming housed. Method: Phase I used a scoping review methodology (Arksey & O’Malley, 2005) to explore existing literature contributing to an understanding of occupational transition during an exit from homelessness. Interpretive phenomenology guided Phases II and III, which involved gathering data through semi-structured interviews with 12 participants who were chronically homeless (Phase II), and 11 participants with a history of chronic homelessness who had recently become housed (Phase III). Data collected in Phases II & III were analyzed using a modified version of the method suggested by Colaizzi (1978). Results: Phase I uncovered the relative paucity of literature focusing on the occupations of homeless persons as they exit homelessness. Phase II identified the unique occupational experiences of chronically homeless persons in a medium-sized city. Chronically homeless persons experienced occupational alienation caused by a lack of participation in mainstream society, and a deep and pervasive boredom that adversely influenced their mental health and drove substance misuse. Phase III identified that as participants transitioned to becoming housed, slow changes in their occupational repertoire positively influenced their mental health and well-being. Implications: Taking a broad view of the occupations of chronically homeless persons reveals several unique aspects of their experiences that can inform interventions designed to support this population as they exit homelessness. Incorporating an occupational approach in concert with a housing first philosophy may lead to a more comprehensive strategy to addressing chronic homelessness.

abstract: The author intends to publish the work in manuscript form in academic journals, and would like to ensure that material submitted to journals has not been considered to be previously published.

abstract: PhD


title: Carbon Sequestration Through the Production of Precipitated Calcium Carbonate From Waste Concrete

contributor:
Zeman, Frank
Jamieson, Heather E.
Environmental Studies

subject:
recycling waste concrete
mineral carbonation
carbon utilization
sustainability
carbon sequestration
zero waste

abstract: Thesis (Master, Environmental Studies) -- Queen's University, 2016-04-19 14:25:41.473

abstract:
As a result of human activities, rising concentrations of atmospheric carbon dioxide (CO2) are causing climate change.  One method to sequester CO2 involves the production of synthetic limestone (CaCO3) from calcium silicate minerals and CO2 via mineral carbonation.  Certain grades of CaCO3, including Precipitated Calcium Carbonate (PCC), are sold as a filler and pigment to several industries.  Therefore, if marketable as PCC, the production of CaCO3 via mineral carbonation may be an economical method to help mitigate climate change.  The global market for PCC offers the potential to utilize several million tonnes of CO2 per year.  Waste cement is a suitable source material for PCC production via mineral carbonation and can be recovered from waste concrete as a byproduct of aggregate recycling practices.
The objective of this research was to investigate the possibility of sequestering CO2 by producing PCC via the recovery and carbonation of waste cement calcium.  An acid (HCl) was used to allow the complete leaching of calcium, and so the dissolved calcium could be separated from the residual material via filtration to enable PCC recovery.  A purification step via pH adjustment preferentially precipitated co-leached impurities such as iron and silicon.  CaCO3 precipitation was later induced by adding Na2CO3 that can be produced by the absorption of CO2 from flue gases or the atmosphere (air capture) using NaOH.  HCl and NaOH can be recycled via bipolar membrane electrodialysis.  Although this method may require over twice the energy of the conventional PCC manufacturing process, low carbon electricity can be used and negative process emissions are currently feasible in multiple Canadian provinces.  Lower energy carbonation methods could be used where stationary sources of concentrated CO2 are located, however air capture is possible and the use of HCl and a purification step allows for the complete carbonation and utilization of waste cement calcium.  This minimizes emissions from hauling residues and may ensure that significantly more CO2 is absorbed by the waste cement than would otherwise be passively absorbed by the material over several decades of atmospheric exposure.

abstract: M.E.S.


title: The Subfornical Organ: An Integrative Site for Reproductive, Cardiovascular, and Metabolic Control

contributor:
Ferguson, Alastair V.
Biomedical and Molecular Sciences

subject:
Signal Integration
Metabolic Regulation
Subfornical Organ
Reproduction
Circumventricular Organs
Cardiovascular Control

abstract: Thesis (Master, Biomedical & Molecular Sciences) -- Queen's University, 2016-04-20 12:09:09.639

abstract: In order to maintain homeostasis, the central nervous system (CNS) must monitor and integrate  signaling molecules such as peptides and hormones that convey information regarding reproductive, metabolic, and cardiovascular status (to name a few) of the organism. Many of these signals are located in circulation and are incapable of crossing the blood brain barrier (BBB), the protective structure surrounding the CNS. Circumventricular organs (CVOs) are specialized structures that lack a BBB and therefore provide a route through which these peripheral signals may access the CNS. This study focuses on the subfornical organ (SFO), a forebrain sensory CVO, and its ability to respond to three different signals, prolactin (PRL), alpha-melanocyte stimulating hormone (α-MSH) and brain derived neurotrophic factor (BDNF), which are involved in the regulation of reproductive, metabolic, and cardiovascular status, respectively. Using whole-cell and perforated patch-clamp recordings, all three peptides were found to influence the excitability of dissociated SFO neurons. Of the 9 neurons that responded to 1 µM PRL, 55% depolarized (mean: 13.6 ± 5.0 mV, n=5) and 45% hyperpolarized (mean:-8.4 ± 2.1 mV, n=4). Similar to this, 10 of the neurons perfused with 250 nM α-MSH responded by either depolarizing (50%, mean: 14.9 ± 5.6 mV, n=5) or hyperpolarizing (50%, mean: -11.0 ± 0.7 mV, n=5). Both response types were also observed in response to 1 nM BDNF as 69% of the 16 responders depolarized (mean: 15.4 ± 2.4 mV, n=11) and 31% hyperpolarized (mean: -12.1 ± 2.0 mV, n=5). A non-selective cation channel potentially mediates the depolarizing response of all three peptides, as suggested by comparing extrapolated reversal potentials for each (PRL: -61.7 mV, α-MSH –55.4 mV, BDNF: -53.3 mV). Additionally, some SFO neurons (12%) were capable of responding to both BDNF and α-MSH. This study is the first to demonstrate electrophysiological consequences of PRL, α-MSH, and BDNF on the excitability of SFO neurons, effects which provide a point at which these peptides could potentially access the CNS from the circulation. Given its numerous efferent projections to autonomic control centers of the CNS involved in reproductive, metabolic, and cardiovascular function, our data suggest the SFO is an important site of integration and information relay for these peptides.

abstract: Work yet to be published

abstract: M.Sc.


title: Labour, Heritage, and the Politics of Difference: Working Class History Museums in the Changing City

contributor:
Mosco, Vincent
Sociology

subject:
Working Class Heritage
Museums
Commodification
Postindustrial Cities
Political Economy
Gentrification
Communication
New Museology

abstract: Thesis (Ph.D, Sociology) -- Queen's University, 2016-04-13 20:49:32.944

abstract: As a contemporary communications medium, the museum has undergone significant reinvention and reorientation of purpose within the past several decades. While the late twentieth century saw the rise of a fundamental reimagining of the museum as a visitor-oriented space where questions of representation, ownership, and voice were of paramount concern, the early twenty-first century has seen a repositioning of museums as market actors with a role to play in the economic aspects of social life. This dissertation probes the growing disconnect between the rhetoric and practices enacted under the auspices of new museology and the ascendancy of corporatized values, interests, and operational forms in museum praxis. It is specifically concerned with working class history museums located in postindustrial urban environments, and seeks to explore and consider some of the inherent tensions in representing labour struggles and working class heritage in gentrifying, capitalist cities. The dissertation reveals that working class history museums face immense challenges in trying to reconcile being socially progressive and class-oriented while also maintaining relevance and success in gentrifying areas. It argues that these museums are embedded within political economic structures of power, and thus face considerable limitations in their efforts to act as meaningful sites of political or ideological contestation. Furthermore, by subscribing to the supposition that heritage resources can be used to spur gentrification and economic development, museums may unwittingly reinforce elite reimaginings of the urban environment. Three case studies are examined: the People’s Palace, a public museum in Glasgow, Scotland; New York City’s Lower East Side Tenement Museum; and finally, the Écomusée du Fier Monde, a small community museum located in the Centre-Sud neighbourhood of Montréal, Canada.

abstract: I intend to publish material from my thesis. I am actively pursuing a book contract.

abstract: PhD


title: Towards Estimating Friction Factors of Mine Drifts from Low Density Point Clouds

contributor:
Marshall, Joshua A.
Mining Engineering

subject:
Point Clouds
Underground Scanning
uGPS
Mine Ventilation
Mining

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2016-04-14 23:09:19.727

abstract: The standard for estimating roughness for the purposes of underground mine ventilation planning is to choose values found in a variety of textbooks that attempt to match the excavation type. These values are then used in the Atkinson equation made popular in 1935 by McElroy to determine pressure drops and energy requirements. The Darcy-Weisbach equation, developed in the 1950s, has been accepted by most other engineering disciplines but lacks critical information for widespread use in underground mines, namely, the friction factor. As the mining ventilation field moves towards the use of simulations and more refined models, a simple and efficient method for extracting the friction factor is needed. This thesis proposes new LiDAR-based methods for estimating this factor in underground mining tunnels. By using a mobile LiDAR platform low density point clouds are collected then analysed to estimate the friction factor and are compared to those calculated from ventilation data gathered at Barrick Gold Corporation - Hemlo. The two original methods described, in addition to four previously published methods, are shown to be applicable to this 3D point cloud data. The original methods and the IBA method, put forward by Rønn and Skog in 1997, are consistent with both the friction factors already in use at the mine and with the ventilation data collected. Ideas for further improving this approach for friction factor estimation are also suggested.

abstract: M.A.Sc.


title: Rock Outcrops in the Canadian Shield: an Investigation of Contaminant Transport From Surface Sources in Fractured Rock Aquifers

contributor:
Novakowski, Kent S.
Civil Engineering

subject:
Transport
Fractured Rock
Colloids
Bacteria
Hydrogeology
Drinking Water
Source Water Protection
Outcrops

abstract: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2016-06-28 09:16:21.171

abstract: Flow, recharge and transport dynamics in fractured rock aquifers with low lying rock outcrops is a largely unexplored area of study in hydrogeology. The purpose of this thesis is to examine these topics in an agricultural area in Eastern Ontario. The study consists of a regional scale groundwater quality study, an infiltration experiment that considers bacteria transport from the ground surface to a well, and a numerical modelling study that tests the parameters that affect surface infiltration of a tracer from a rock outcrop to a deeper horizontal fracture. In the water quality study, approximately 65% of the samples contained total coliform, 16% contained E. coli, and 1% contained nitrate-N at greater than 5 mg/L. Occurrence of E. coli increased when considering seasonality, where wells were drilled on rock outcrops, and for shallow well intervals. Nitrate-N did not occur above the Guidelines for Canadian Drinking Water Quality (Health Canada, 2012) of 10 mg/L. Rapid arrival times were observed in the infiltration study for both the microspheres (30 minutes) and a dye tracer (45 minutes) in a well approximately 6.0 m in horizontal and 2.8 m in vertical distance from the tracer source. Transport velocities were approximately 38.9 m/day for the dye tracer and 115.2 m/day for the colloidal tracer. Results of the model runs indicate that overburden can provide an effective protective layer to transport in fractures, that high groundwater velocities occur in larger fracture apertures and higher gradients dilute tracer concentrations, and that lower groundwater velocities occur with smaller fracture apertures and lower gradients result in elevated tracer concentrations. Lower rainfall rates, larger fracture apertures, early tracer time, larger gradients, and lower water levels maintained unsaturated conditions for longer time periods such that tracer transport was delayed until saturated conditions were attained. The overall heterogeneity of this aquifer environment creates a source water protection conundrum where the water quality is generally good, while transport can occur very quickly in proximity to rock outcrops and in areas with limited overburden.

abstract: PhD


title: Assessing water resource management in provincial land use planning policies in peri-urban regions of Southern Ontario

subject:
Water resource management
Land use planning
Urbanization
Ontario

abstract: Urbanization is one of the most significant trends of the 21st century, affecting global economic development, energy consumption, natural resource use and human well-being. Land- use planning is a tool used by local and regional municipalities to address these increasing development pressures. Currently, provincial land use plans for ecologically and economically important regions within the Greater Golden Horseshoe, including the Oak Ridges Moraine Conservation Plan, the Niagara Escarpment Plan and the Greenbelt Plan, are undergoing a Coordinated Land Use Plans Review, which commenced in 2015. Scholarly and grey literature was examined to evaluate these land use plans using criteria based on Integrated Water Resource Management and Monitoring. Select strengths, weaknesses and recommendations were provided for Oak Ridges Moraine, Niagara Escarpment and Greenbelt land use plans to move toward adaptive environmental management.


title: Lethal and sub-lethal defects demonstrate the chronic toxicity of chemically-dispersed diluted bitumen to rainbow trout embryos (Oncorhynchus mykiss)

subject:
dilbit
toxicology
rainbow trout
CEWAF

abstract: Addition of a low molecular weight diluent to raw bitumen from Alberta’s Oil Sands produces diluted bitumen (dilbit), a physically and chemically distinct product from conventional oils. While thousands of kilometers of pipeline carry dilbit across Canada, relatively few studies have documented its environmental behaviour and toxicity to developing fish in the event of a spill to freshwater. In response, this study demonstrated exposure-response relationships between dilbit at a gradient of concentrations and toxicological responses of rainbow trout embryos under standardized laboratory conditions. Chronic toxicity was measured by exposing rainbow trout embryos for 25 days to two different winter dilbit blends, Access Western Blend (AWB) and Cold Lake Blend (CLB). Chemical dispersion of hydrocarbons from AWB and CLB dilbit into water (producing chemically enhanced water accommodated fractions, CEWAFs) was used to prepare exposure solutions. Endpoints to characterize chronic toxicity included mortality, impairment of growth and development, and select morphological deformities collectively called blue sac disease (BSD). Results indicated that cumulative mortality and the prevalence of sub-lethal defects (i.e. impairment of growth and development and onset of BSD) increased with increasing exposure concentration of dilbit CEWAF in water. Additionally, at the same volume of CEWAF, CLB had a higher total petroleum hydrocarbon content and higher lethal toxicity to rainbow trout embryos (25-d LC50 = 1200 g/L) than AWB (25-d LC50 = 1627 g/L). AWB and CLB were 2 and 2.7 times more toxic respectively when compared to a light crude oil (22-d LC50 = 3281 g/L), and 3.4 and 2.5 times less toxic respectively when compared to a heavy fuel oil (25-d LC50 = 473 g/L). This research contributes to developing a dilbit-specific assessment of toxicity and potential impacts (i.e., recruitment failure and declining populations of fish species whose spawning coincides with an oil spill) if the product is spilled into a freshwater environment.

abstract: Natural Sciences and Engineering Research Council of Canada (NSERC), Department of Fisheries and Oceans Canada


title: Binary: a Framework For Big Data Integration For Ad-Hoc Querying

contributor:
Martin, Patrick
Zulkernine, Farhana
Computing

subject:
Ad-Hoc Query
Big Data

abstract: Thesis (Master, Computing) -- Queen's University, 2016-04-19 01:11:59.897

abstract:
Traditional relational database systems are not practical for big data workloads that require scalable architectures for efficient data storage, manipulation, and analysis. Apache Hadoop, one of these big data frameworks, provides distributed storage and processing as well as a central repository for different types of data from different sources. Data integration from various sources is often required before performing analytics. Apache Hive on Hadoop is widely used for this purpose, as well as for data summarization and analysis. It has features such as a SQL-like query language, a Metastore to hold metadata and file formats to support access to various frameworks on Hadoop and beyond. For comprehensive analysis and decision-making, however, a hybrid system is required to integrate Hadoop with traditional relational database management systems in order to access the valuable data stored in relational databases. Current hybrid systems are either expensive proprietary products or require a system to be developed by the user, which requires programming knowledge. In addition these approaches are not sufficiently flexible to be applied to other frameworks.
In this thesis, we propose a framework called BINARY (A framework for Big data INtegration for Ad-hoc queRYing). BINARY is a hybrid Software as a Service that provides a web interface supported by a back-end infrastructure for ad-hoc querying, accessing, visualizing and joining data from different data sources, including Relational Database Management Systems and Apache Hive. Our framework uses scalable Hive and HDFS big data storage systems and supports different data sources via back-end resource adapters. There is also a front-end web interface that enables the use of HiveQL to query the data sources.
The framework is extendable and allows adding other storage engines (e.g. HBase) and analytics engines (e.g. R) as needed. We used REST software architecture to enable loose connections between the engines and the User Interface programs to facilitate independent updates without affecting the data infrastructure. Our approach is validated with a proof-of-concept prototype implemented on the OpenStack cloud system.

abstract: M.Sc.


title: Molecular Code Division Multiple Access: Gaussian Mixture Modeling

subject:
Nano-Networking
Molecular Communication (MC)
Gaussian Mixture Modeling
MCDMA

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2016-04-19 11:22:10.551

abstract:
Communications between nano-devices is an emerging research field in nanotechnology. Molecular Communication (MC), which is a bio-inspired paradigm, is a promising technique for communication in nano-network. In MC, molecules are administered to exchange information among nano-devices. Due to the nature of molecular signals, traditional communication methods can’t be directly applied to the MC framework. The objective of this thesis is to present novel diffusion-based MC methods when multi nano-devices communicate with each other in the same environment. A new channel model and detection technique along with a molecular-based access method, are proposed in here for communication between asynchronous users.
In this work, the received molecular signal is modeled as a Gaussian mixture distribution when the MC system undergoes Brownian noise and inter-symbol interference (ISI). This novel approach demonstrates a suitable modeling for diffusion-based MC system. Using the proposed Gaussian mixture model, a simple receiver is designed by minimizing the error probability. To determine an optimum detection threshold, an iterative algorithm is derived which minimizes a linear approximation of the error probability function. Also, a memory-based receiver is proposed to improve the performance of the MC system by considering previously detected symbols in obtaining the threshold value. Numerical evaluations reveal that theoretical analysis of the bit error rate (BER) performance based on the Gaussian mixture model match simulation results very closely.
Furthermore, in this thesis, molecular code division multiple access (MCDMA) is proposed to overcome the inter-user interference (IUI) caused by asynchronous users communicating in a shared propagation environment. Based on the selected molecular codes, a chip detection scheme with an adaptable threshold value is developed for the MCDMA system when the proposed Gaussian mixture model is considered. Results indicate that the MCDMA system is a promising approach to reduce interference created by asynchronous nodes in multi-user MC systems. Meanwhile, the receiver is modified by exploiting previously detected chips to eliminate the ISI. The performance evaluations via computer simulations show that the memory-based receiver, which considers previously detected chips in detection procedure, outperforms the memory-less receiver.

abstract: M.A.Sc.


title: Novel High Power Density Topologies and Control for the Point-of-Load (POL) Application

subject:
Power Electronics
POL Converter
DC-DC Converter

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2016-04-19 19:19:01.507

abstract:
High performance microprocessors are promoting the development of modern electronic devices such as smart phones and tablets. These microprocessors have stricter requirement on the power supplies in terms of efficiency and overall size since power supplies are directly affecting performance of microprocessors. These power supplies are directly built right next to loads and they are called Point-of-Load (POL) power supplies.
The conventional Buck converter has been the dominant method for implementing non-isolated DC-DC POL power supplies. With the increasing demand to miniaturize the voltage regulators for computers and telecommunication products, high power density POL converter topologies are highly desirable in satisfying this trend. But the difficulty of increasing power density of Buck converter makes Buck no longer to be a good candidate for modern electronic devices. In this thesis, two topologies are proposed to address this issue.
First of all, the Asymmetrical Three-Level (ATL) converter is proposed. ATL features reduced voltage and doubled equivalent operating frequency on the inductor compared with the conventional Buck and three level Buck converter.
Secondly, the modified Asymmetrical Three-Level (mATL) converter is proposed for the application of high output current. The two-phase mATL converter has reduced voltage and doubled equivalent operating frequency on each inductor compared with the two-phase Buck converter. Also, two interleaved inductor current cancels each other to reduce output current ripple.
Finally, the inherent automatic inductor-current sharing mechanism of mATL converter is demonstrated and studied. Also, a new control scheme, Negative Circulating Control (NCC) scheme is proposed to achieve automatic inductor-current sharing in discontinuous conduction mode. Besides, a new control scheme is proposed to extend the output voltage range of mATL converter.

abstract: M.A.Sc.


title: The Personal Politics of Spirituality: On the Lived Relationship Between Contemporary Spirituality and Social Justice Among Canadian Millennials

contributor:
Miller, James
Cultural Studies

subject:
Contemporary Spirituality
Millennials
Spiritual but Not Religious
Social Justice

abstract: Thesis (Master, Cultural Studies) -- Queen's University, 2016-04-19 21:45:21.146

abstract: In the last quarter century, a steadily increasing number of North Americans, when asked their religious affiliation, have self-identified as “spiritual but not religious” (SBNR). Resultantly, a wealth of literature on the subject of contemporary spirituality has recently emerged. Some suggest, generally, that we are seeing the emergence of a “progressive spirituality” that is potentially transformative and socially conscious. Conversely, there are scholars who have taken a more critical stance toward this recent cultural development, positing that contemporary spirituality is a byproduct of the self-obsessed culture which saturates the west, or that spirituality, at its worst, is simply a rebranding of religion in order to support consumer culture and the ideology of capitalism. One problem with the majority of this literature is that scholars have tended to offer essentialist or reductionist accounts of spirituality, which rely primarily on a combination of theoretical and textual analysis, ignoring both the lived aspect of spirituality in contemporary society and its variation across generations. This thesis is an attempt to mitigate some of this controversy whilst contributing to this burgeoning scholarly field. I do so by shedding light on contemporary spirituality, as it exists in its lived form. Espousing a lived religion framework, and using the qualitative data I collected from conducting semi-structured interviews with twenty Canadian millennials who consider themselves “spiritual but not religious,” I assess the cogency of the dominant etic accounts of contemporary spirituality in the academic literature. I offer a critical analysis of their normative conclusions in light of the lived accounts of my research participants. Using four core ethics—the ethic of self-responsibility, the ethic of authenticity, the ethic of productivity, and the ethic of self-awareness—pertaining to the shared framework of self-spirituality as focal points of analysis, this thesis looks to flesh out the lived relationship between contemporary spirituality and social justice related attitudes and action among Canadian millennials.

abstract: M.A.


title: The Technospheric Mining of Rare Earth Elements for Sustainable Technologies

subject:
Rare earth elements
Recycling
Technospheric mining

abstract:
Rare earth elements play a critical role in creating a sustainable society because they compose vital components of sustainable technologies such as wind turbines, electric and hybrid cars, and fluorescent lights. Despite their positive influence on the environment, their extraction and production is  environmentally hazardous. It produces more greenhouse gases per kg of oxide than many other ores, and uses chemically intensive methods that create wastewater issues and environmental contamination. Furthermore, without the availability of these minerals, the production and advancement of these technologies would be reduced. The market is currently experiencing a gap in supply due to the decreased export quota from China. Technospheric mining provides an opportunity to reduce the environmental impact of the production of rare earth elements, as well as increase the supply for further development of sustainable technologies.
	Technospheric mining looks at three main categories of stocks as a resource for rare earth elements; pre-consumer fabrics, post-consumer products, and historic urban and industrial landfills. These three categories provide numerous options for rare earth recovery. However, unless advancements in processing technologies are made, the production of recyclates will have the same negative processing effects as virgin ores. Each resource has very different properties and the technologies must address this. Furthermore, if this technique is to be successful, legislation encouraging recycling needs to be applied.