title: Development of a semi-autonomous directional and spectroscopic radiation detection mobile platform

contributor:
Machrafi, Rachid
Mohany, Atef

subject:
Gamma ray detector
Radioactive source localization
Lanthanum bromide
Radiation detection robot

abstract: This thesis presents a method for a small, inexpensive mobile robot equipped with a single high resolution scintillation detector to quickly survey an area and convey information about local sources of gamma radiation to a remote human operator. This is achieved by surrounding the detector with a lead sheath that blocks all gamma rays except those incident along the detector’s axial direction. A horizontal scan is performed by rotating the detector and a directional profile of gamma radiation is constructed. In addition a visual panorama of the local area is assembled using a camera mounted on the detector. A plot of the detector signal versus angle is then overlaid on top of the visual panorama and visible peaks clearly indicate the direction of local gamma radiation sources. Moreover, measuring the energy spectrum of gamma rays in each direction produces a 2D count frequency histogram where distinct peaks indicate the energy and direction of local gamma ray sources allowing the identification of different radio-isotopes.


title: Towards sustainable machining of difficult-to-cut materials using nano-cutting fluids

subject:
Machining
Sustainability
Difficult-to-cut materials
Nano-fluids

abstract:
Providing environmentally friendly conditions and optimizing energy consumption are two essential requirements in order to achieve sustainable machining processes. One of the major sustainable machining concerns is the implementation of cutting fluids due to its significant impact on the machining quality characteristics. In addition, several economic, environmental, and health problems take place due to the inappropriate application of cutting fluids, therefore, previous research has introduced advanced cutting fluids technologies in order to optimize the cutting fluids usage during machining. However, there are still issues related to machining difficult-to-cut materials that have not been addressed and need to be improved. These materials have superior characteristics such as high strength to weight ratio, corrosion resistance, temperature resistance, and chemical stability, allowing them to be materials of choice in the aerospace, automotive, oil and gas, and bio-medical industries. Despite their desired characteristics, the wide spread applications of these materials has been compromised by several difficulties that arise during machining.
Flood cooling is a typical cooling strategy used in industry to dissipate the high heat generated during machining difficult-to-cut materials; however, the use of flood coolant has raised environmental and health concerns which call for different alternatives. Minimum Quantity Lubricant (MQL) has been successfully utilized as an acceptable coolant strategy; however, its potential to dissipate heat is much lower than the one achieved by flood coolant. One of the best techniques to enhance MQL heat capacity is the application of nano-cutting fluids as they offer significant enhancement in the tribological and heat transfer characteristics.
The main objective of the proposed research is to fully investigate and understand the influence and role of dispersed multi-walled carbon nano-tubes (MWCNTs) into vegetable oil by implementing the minimum quantity lubrication (MQL) technique during turning Ti-6Al-4V titanium alloy and Inconel 718. The Investigations include study of the energy consumption, tool wear behavior, chip morphology, and surface quality when using nano-cutting fluids based MQL. The study revealed that nano-fluid based MQL improves the tool performance and proves clear advantage over the traditional/classical MQL.
In order to provide a solid physical understanding of the studied cutting processes using MQL-nano-fluids, the tribological aspects of the process and heat transfer mechanisms have been analyzed and investigated. The study presented a comparative performance analysis between MWCNTs and aluminum oxide (Al2O3) nano-cutting fluids. Additionally, an integrated finite element (FE) model has been developed in order to simulate the thermal and frictional effects of the MQL-nano-fluid to study various unique cutting aspects such as generated cutting temperature and residual stresses.
Furthermore, a general and detailed assessment model is developed and used to assess the sustainability of machining processes. Energy consumption, machining costs, waste management, environmental impact, and personal health and safety have been used to express the overall sustainability assessment index. It should be stated that the model predictions agree with the experimental findings. As such, the developed model offers a valuable tool to optimize the sustainability aspects of machining process.

abstract: University of Ontario Institute of Technology


title: Exploring the use of mathematics apps in the elementary school classroom

subject: Mathematics Elementary Tablets Apps Classroom

abstract: Many reports indicate that students have difficulty in mathematics (Carr, 2012; Hinton, 2014; National Assessment of Educational Progress, 2013). Some evidence suggests that technology can help improve student performance in the field (Boogart et al., 2014; Riconscente, 2013). This study investigates how the use of digital mathematics applications (apps) in a grade 2/3 class could affect student attitudes and academic performance by assessing and comparing the quality of different apps. Five specific apps, Thinking Blocks, Sushi Monster, Math Tappers, Prodigy, and Show Me, were carefully selected based on set criteria. This study used a mixed methodology, including survey data, open-ended questions, interviews, and performance tests. Twenty students, including eleven grade 2 (six males, five females) and nine grade 3 (five males, four females), participated in this study. The results indicated the importance of focusing on specific types of mathematics apps rather than focusing on the technology itself. The students enjoyed the challenge of solving math problems and believed this helped them learn. The game-based apps, especially the micro-world type app, were some of the favourite apps that the students selected because it engaged them, provided positive feedback, and they were able to create customised characters. The students preferred to use fun and easy apps rather than those that were more complicated to use. Students’ mathematics performance significantly increased after the use of math apps, but other factors, such as the quality of the teacher’s instruction, additional use of mathematics manipulatives, and support from home could have influenced the results.


title: Nintendo Wii versus resistance training to improve upper-limb function in children ages 7 to 12 with spastic hemiplegic cerebral palsy: a home-based pilot study

subject:
Hemiplegia
Nintendo Wii
Resistance training

abstract: This pilot, home-based study compared a Nintendo Wii intervention to a single-joint upper-limb resistance training of a similar intensity, in n=6 children ages of 7 to 12 with spastic hemiplegic CP with respect to upper limb function, compliance and motivation levels. The main results found that all participants in the Wii intervention group (n=3) experienced positive changes in more than one assessment from pre-test  to follow-up, and these changes were on average greater than those experienced by the resistance training group (n=3). Also, the Nintendo Wii group had a higher compliance rate, and higher parent-reported motivation levels throughout the study. This suggests that Nintendo Wii interventions for the upper limbs may be a more effective home-based rehabilitation strategy than the single-joint upper limb resistance training program used in this study, due to greater participant motivation to comply with Nintendo Wii training. These findings warrant further research.


title: Bridging the digital divide: examining the use and access to e-health based technologies by millennials and older adults in Ontario, Canada

subject:
Digital divide
ICT
Older adults
Millennials
Technology

abstract: The digital divide is the gap between demographics and regions that have access to information communication technologies and those who do not. The older adult generation may not be familiar with e-Health usage, compared to generations such as millennials. A convenience non-random descriptive comparative study was conducted; Information was collected based on demographics; health information collection, usage and distribution; E-health and e-health technology usage; and digital literacy levels. Millennials (n=31) were undergraduate students recruited at Ontario Tech University; Older adults (n=28) were recruited from senior centres in the Durham region. Data was examined using sex and age cohort, to identify any statistically significant differences. Results showed that older adults had a decreased understanding of E-health based technologies, digital literacy, and accessed the internet less. These preliminary findings suggest that there are noted challenges facing older Canadians in terms of utilization of e-health technologies, in comparison to younger Canadians in Ontario.


title: Design and development of a novel anthropomorphic finger with pneumatic tactile sensing

subject:
Robotics
Tactile sensors
Pneumatics
Collaborative
Machine learning

abstract:
The human hand is a tool that we rely on to conduct a vast variety of tasks, from cracking eggs to lifting boxes. Meanwhile, in an industrial setting, different tools are needed to complete specific tasks. Picking up a box may require parallel grippers, while grabbing an egg may need suction cups. Having one tool to accomplish both jobs saves time and money for tooling changes when a new product is manufactured. Hence, the need for anthropomorphic (human-like) grippers has risen over time.
This work outlines the creation of an anthropomorphic finger and pneumatic tactile sensor. This underactuated and compliant finger design is optimal for an industrial or collaborative environment, while the pneumatic sensor is proven to be sensitive and accurate for tactile feedback of grasped objects. This feedback consists of force measurement and slip detection, which is required for efficient object manipulation.


title: Development and investigation of integrated solar systems for hydrogen and methanol production

contributor:
Dincer, Ibrahim
Naterer, Greg

subject:
Hydrogen production
Solar energy
Photoelectrochemical process
Methanol
Efficiency

abstract:
Implications of climate change, in particular the negative effects of greenhouse gas (GHG) emissions resulting from fossil fuel combustion, as well as the finite nature of fossil fuels necessitate the implementation of reliable and environmentally benign alternative energy options. This is particularly true for transportation and power generation sectors, which are responsible for the majority of carbon dioxide emissions. Hydrogen is a clean fuel that can be produced from renewable energy via electrolysis and direct photonic energy conversion from sunlight, produces no harmful emissions in combustion, and can be converted to electricity via fuel cells with good efficiency. However, it is challenging to store H2 in a cost and energy efficient manner, and it is not widely available to consumers in comparison to traditional liquid fuels for transportation applications. Storage of H2 produced from solar energy in synthetic fuels is a key step in moving towards an eventual hydrogen economy. By conversion to synthetic fuels such as methanol, hydrogen and solar energy may be directly utilised in current infrastructures as liquid fuels for transportation or in power generation applications.
This thesis experimentally investigates clean hydrogen production from solar energy and water using a novel photoelectrochemical water-splitting reactor designed, built, and tested at the Clean Energy Research Laboratory in UOIT. Integrating solar concentration and a spectrum-splitting mirror allows simultaneous photovoltaic electricity generation and direct photonic energy conversion to split water via PEM electrolysis and photoelectrochemical water splitting on the custom built photocathode of the reactor. Case studies are presented for system integration with methanol synthesis from solar energy and anthropogenic carbon capture for environmentally benign fuel production.


title: Impact of carbon micro/mesoporosity on the adsorption behavior of small molecules

subject:
Carbon
Mesoporous materials
Adsorption
Glucose
Melamine

abstract:
Adsorption studies on carbon play a key role in fields such as environmental remediation, purification, and catalysis. Because of the inherently high surface area, low cost, and inertness of activated carbons, these materials have been the preferable substrate for remediation studies. The adsorption of mercury, radioactive materials, pesticides, and dyes from soil and water are only a few examples among others. Considerably less time has been dedicated to investigating adsorption processes on other types of carbons such as carbon blacks, graphene, or carbon nanotubes, despite the fact that these materials are used extensively in energy conversion and storage devices, and applications in the field of catalysis and electrocatalysis.
This thesis work is aimed to fill the gap in existing research by studying the adsorption of two model molecules, glucose (C6H12O6) and melamine (C3H6N6) onto three different wellcharacterized carbon substrates, two commercial carbon materials with very different properties, Darco KB-G (AC) and Vulcan XC-72R (VC), and a mesoporous carbon synthesized for this purpose. The adsorption of glucose was examined using both gas chromatography and thermogravimetric analysis, while melamine adsorption was studied using UV-visible spectroscopy. The effect of different phase separation techniques on TGA results was analyzed.
Melamine adsorption isotherms in both acid and alkaline media were fit with both the Langmuir and Freundlich models. To the best of our knowledge, these are the first reported values for the adsorption of melamine on mesoporous carbon materials.


title: Alloy catalysts for fuel cell-based alcohol sensors

subject:
Breath alcohol sensor
Fuel cell sensor
Breathalyzer
Proton exchange membrane fuel cell
Direct alcohol fuel cell

abstract: Direct ethanol fuel cells (DEFCs) are attractive from both economic and environmental standpoints for generating renewable energy and powering vehicles and portable electronic devices. The cost and performance of the DEFCs are mainly controlled by the Pt-base catalysts used at each electrode. In addition to energy conversion, DEFC technology is commonly employed in the fuel-cell based breath alcohol sensors (BrAS). BrAS is a device commonly used to measure blood alcohol concentration (BAC) and enforce drinking and driving laws. The BrAS is non-invasive and has a fast respond time. However, one of the most important drawback of the commercially available BrAS is the very high loading of Pt employed. One well-known and cost effective method to reduce the Pt loading is developing Pt-alloy catalysts. Recent studies have shown that Pt-transition metal alloy catalysts enhanced the electroactivity while decreasing the required loadings of the Pt catalysts. In this thesis, carbon supported Pt-Mn and Pt-Cu electrocatalysts were synthesized by different methods and the effects of heat treatment and structural modification on the ethanol oxidation reaction (EOR) activity, oxygen reduction reaction (ORR) activity and durability of these samples were thoroughly studied. Finally, the selected Pt-Mn and Pt-Cu samples with the highest EOR activity were examined in a prototype BrAS system and compared to the Pt/C and Pt3Sn/C commercial electrocatalysts. Studies on the Pt-Mn catalysts produced with and without additives indicate that adding trisodium citrate (SC) to the impregnation solution improved the particle dispersion, decreased particle sizes and reduced the time required for heat treatment. Further studies show that the optimum weight ratio of SC to the metal loading in the impregnation solution was 2:1 and optimum results achieved at pH lower than 4. In addition, powder X-ray diffraction (XRD) analyses indicate that the optimum heat treatment temperature was 700°C where a uniform ordered PtMn intermetallic phase was formed. Although the electrochemical active surface area (ECSA) decreased due to the heat treatment, the EOR activity of Pt-Mn samples was improved. Moreover, it was shown that the heat-treated samples prepared in the presence of SC showed superior the EOR activity compared to the samples made without SC. The Pt-Cu/C alloys were produced by three different methods: impregnation, impregnation in the presence of sodium citrate and microwave assisted polyol methods. These studies showed that the polyol method was the optimum method to produce the Pt-Cu alloy. The XRD analysis indicates that the heat treatment at 700 °C developed catalysts rich in the PtCu and PtCu3 ordered phases. The highest EOR activity was measured for the Pt-Cu/C-POL (sample made by the polyol method) and heat treated at 700°C for 1h. Comparing the EOR activity of the Pt-Cu and Pt-Mn samples also demonstrates that the heat treated Pt-Cu/C-POL sample showed higher EOR activity compared to the Pt-Mn samples. These results indicate that the benefits of thermally treating alloy nanoparticles could outweigh any activity losses that may occur due to the particle size growth and the ECSA loss. Besides, accelerated stress tests (ASTs) illustrate that the heat treatment improved the durability of the Pt-Mn and Pt-Cu samples. The durability and EOR activity of the heat treated Pt-Mn and Pt-Cu samples was similar or better than commercial samples. On the other hand, the ORR activity of Pt-Mn and Pt-Cu after the heat treatment was slightly lower than the commercial samples but the ORR activity loss can be compensated by the economic benefits from using the lower Pt loading. Finally, studying the alcohol sensing characteristic of different samples shows that the heat treated Pt-Mn and Pt-Cu catalysts could be used for the ethanol sensing. Additionally, among the different commercial samples tested for ethanol sensing, Pt-Sn/C showed the highest sensitivity but with slightly higher standard deviation. Further studies on the Pt- Cu/C and Pt-Mn/C samples indicate that the heat treatment improved the sensitivity of these samples and the highest normalized sensitivity among all the samples belonged to the Pt-Cu/C-POL (sample produced by polyol method) and heat treated at 700°C. It can be concluded that the heat treated Pt-Mn and Pt-Cu samples could be used as an alternative to replace Pt black in commercial sensors which would dramatically decrease the Pt loading. This could reduce the price and increase the sensitivity of commercial alcohol sensors.


title: A lot of these things nobody talks about: South Asian Muslims' perceptions of dating behaviours and abuse

subject:
Dating abuse
South Asian
Muslim
Islam
Intersectionality

abstract:
The unique meanings people of varying cultures and religions assign to dating
behaviours/abuse along with the context in which these meanings are created are largely
neglected in dating abuse research. Applying intersectionality, I examine understandings
of dating behaviours/abuse from the perspective of South Asian Muslims in Canada. To
unravel the context in which these perceptions are formed, I use intersecting
characteristics that emerged as themes in 11 qualitative interviews, which include:
individual identities, influences of South Asian Muslim and mainstream Western
cultures, and personal perceptions of dating. The majority of participants used religion,
cultures, and nations as identifiers, perceived their communities to be opposed to dating,
and felt pressure to date stemming from Western society. I argue that these intersect to
shape their personal perceptions of dating and the meanings and significance of dating
behaviours/abuse, which revolved around: significance of exposure and sexual
behaviours, control, relationship attachment, and psychological behaviours/abuse.


title: Physiological responses to pedal-assist e-bike use in older adults

subject:
Aging
Physical activity
E-bike(s)
Pedelec(s)
Exercise intensity

abstract: Pedal-assist electric bicycles (pedelecs) have been found to elicit moderate-to-vigorous intensity physical activity (MVPA) in younger adults, however, it is unknown if pedelec riding elicits MVPA in older adults or if loading the pedelec changes the level of e-assist used, and thus the intensity of the activity completed. Participants (n=21, mean age 70.1 ± 5.1) completed a maximal exercise test followed by two 6.25km outdoor pedelec rides at a self-selected comfortable pace, once with 20kg of load added and once without, in random order. Nearly all participants (19/21) achieved a mean intensity of MVPA. Mean intensity from unloaded and loaded rides was 76% HRmax and 75% HRmax, respectively. No differences were observed when comparing HRavg, HRpeak, POavg or POpeak between unloaded and loaded pedelec rides. Older adults self-select at least MVPA while riding pedelecs on a closed course. The added load did not change the intensity of pedelec riding.


title: Race, place and crime through the lens of Toronto’s print media

subject:
Crime
Frame analysis
Moral panic
Race
Racialization

abstract:
Geographical areas with high concentrations of impoverished racialized groups
tend to experience disproportionate rates of violence in Canada. As news media heavily
focuses on crime reports, violence often comes to characterize the affected
neighbourhoods. News reports can impact audience levels of fear and scholars argue that
disproportionate reporting of crime-related events can instil fear among the public. To
date, there has been no study that examines a moral panic of neighbourhoods. Therefore,
this thesis examines how the racialization of crime and the criminalization of place
coalesce to create a moral panic of a neighbourhood. To examine the media’s role in
creating fear, two Toronto newspapers were sampled over a 14-year period. A frame
analysis was conducted to investigate how Toronto newspapers framed Kingston-
Galloway between 1998-2012. Findings suggest that Toronto newspapers racialize crime
and criminalize place, which may aid in the construction of a moral panic of a
neighbourhood.


title: Investigating the distribution of Nitellopsis obtusa in Ontario Lakes and its role as an ecosystem engineer

subject:
Nitellopsis obtusa
Invasive species
Ecological niche model
Internal loading
Ecosystem engineer

abstract: Nitellopsis obtusa is a non-native macrophyte introduced into the Laurentian Great Lakes in 1974. Over the last decade, increasing reports emerged for N. obtusa within lakes in the Great Lakes Basin. Despite N. obtusa being in North America since the 1970s, little is known about the ecosystem- and community-level impacts upon establishment. My thesis aimed to elucidate these potential effects by focusing on both within-lake and regional scale N. obtusa populations. I conducted a comprehensive investigation into ecosystem impacts of N. obtusa across 12 sites in Lake Scugog, Ontario, Canada, from spring to fall over four years (2016-2019). Upon N. obtusa establishment, diversity across lower aquatic food web (LAFW) communities significantly (p-value < 0.05, multiple linear regression) decreased. Despite community diversity decreased across the LAFW, Microcystis spp. blooms emerged where they were previously unreported. To assess drivers of bloom development, a structural equation model demonstrated that N. obtusa had a direct faciliatory (p-value < 0.05) role in Microcystis spp. blooms. In addition, N. obtusa biomass was a moderately strong negative predictor of near-bed oxygen concentration (R2 = 0.59, p-value < 0.001), which likely promoted internal loading of phosphorus. Supporting this conclusion was a strong predictive model showing that N. obtusa biomass explained 90% of pore water soluble reactive phosphorus concentrations (R2 = 0.90, p-value < 0.001). During a narrow sampling window (3 weeks) in 2019, I sampled 60 lakes across a geological transition zone in Ontario, Canada. Calcium is for N. obtusa, thus a strong response related to calcium availability was expected. Nitellopsis obtusa was documented at 37 sites in 19 of the study lakes. Interestingly, an ecological niche model demonstrated that depth and the cations potassium, magnesium, and sodium were better predictors of N. obtusa presence than calcium. Strong positive associations between N. obtusa and native Characeae members were revealed through general linear latent variable modelling, in addition to strong negative associations with other macrophyte taxa such as Myriophyllum spicatum. In combination, these findings indicate that N. obtusa may be an ecosystem engineer in invaded lakes by affecting key lake elements and altering community composition throughout the LAFW community.


title: "Walking the talk" in the integration of chronic disease prevention management: dietitians' perspectives regarding diabetes management in adult peritoneal dialysis programs in Ontario

subject:
Dietitians
Perspectives
Diabetes
Peritoneal dialysis

abstract:
Ontario’s Chronic Disease and Prevention Framework (CDPM) is a framework
aimed at improving health outcomes and reducing costs. Currently, there is a paucity of
data examining diabetes management (DM) in peritoneal dialysis (PD) programs. This
study, carried out in 2010-11, describes dietitians’ perspectives regarding DM in PD
programs in Ontario. Purposeful sampling of dietitians employed in PD programs (n=18)
resulted in a response rate of 86.6%. A web-based survey collected data on demographic
characteristics of PD clients, program models, and program-specific data regarding
facilitators and barriers to provision of dialysis-specific diabetes education. Statistical
analysis was completed and responses to open-ended questions examined using thematic
open-coding. Findings suggest three major themes: “walking the CDPM talk”, dietitians
as “unrecognized CDPM champions” and “the missing pieces to the CDPM puzzle”.
Results suggest that while many dietitians have embraced CDPM, their capacity to fully
integrate it into their practices is limited by organizational- and system-level barriers.


title: Exploring the flipped classroom in a community college setting

subject:
Flipped classroom
Inverted teaching
Blended learning
Community college
Postsecondary education

abstract: The purpose of this study was to explore the flipped classroom approach in a community college setting and assess its impact on students’ learning experience and performance. Participants in this study were second semester computer programming students (n = 103) at a mid-sized community college of applied arts and technology. This study used a convergent parallel mixed method design to compare three different teaching methodologies: a flipped classroom approach, an active/collaborative approach, and a conventional lecture/assignment approach. Garrison’s (2012) Community of Inquiry framework was used to assess the student learning experience afforded by each approach. The flipped classroom approach was rated significantly higher than the lecture/assignment approach in terms of the overall learning experience (p < .05, d = 0.39) and social presence (p < .05, d = 0.53). The active/collaborative approach was rated significantly higher than the lecture/assignment approach for the overall learning experience (p < .05, d = 0.54), overall attitudes and preferences (p < .05, d = 0.49), teaching presence (p < .05, d = 0.43), and social presence (p < .05, d = 0.71). There was no significant difference in student performance with regard to content knowledge among the three approaches.


title: An exploration of the developmental sport and training histories of Canadian sport officials

subject:
Referee
Competitive officiating
Canadian
Expertise development
Sport participation

abstract: Sport officials occupy essential roles in sport and are necessary for sport to function properly. However, compared to athletes and coaches there has been scant research conducted on the development of sport officials. Therefore, the purpose of this thesis was to explore the developmental pathways and milestones that might relate to success as an official. A sample of 223 Canadian sport officials completed The Developmental History of Officials Questionnaire, which collected information on sport and officiating participation histories, as well as training histories related to officiating. Results suggest that respondents’ highest level of athletic performance was predictive of a similarly high level as an official (H(3, n = 217) = 13.37, p < .01, η2 = 0.06), thus past athletic participation might be beneficial for future officials’ development. Additionally, starting at a younger age as an official was also predictive of reaching a higher level as an official (F(3, 212) = 9.09, p < .001, η2 = 0.90). Competitive officiating was the most relevant activity for skill development, with national/international level referees consistently officiating more hours throughout their career, while practice activities were not as prevalent. Future studies should attempt to increase the sample size, widen the variety of sports represented, and gather more respondents from lower- and middle-tier officiating backgrounds.


title: Design and control of resilient micro-inverter system

subject:
Micro-inverter
Micro-inverter system
Resiliency
Key performance indicators
Dual mode inverter

abstract: The growing implications of climate change have created an increasing demand for clean and renewable energy sources. Solar photovoltaics (PV) are increasingly popular as an alternative energy source due to the fact that they produce clean and renewable power with zero operating emissions. However, PV industries are facing issues of unreliability and low product life spans for the connected inverters. These issues can hinder the future growth of the industry. The aim of this research was therefore to design a micro-inverter system with improved resiliency for grid connected applications. The thesis is broken into the Inverter phase and the Resiliency phase. The Inverter phase consisted of the design of two inverters: a 300W micro-inverter and a 600W inverter simulated in PSIM. The Resiliency phase focused on the application of the designed inverters into four case studies for improving the resiliency of a PV system. It was found that placing an extra micro-inverter in parallel to the overall system was the most cost effective design with a high efficiency.


title: Numerical investigation of turbulent	combustion regimes on localized forced	ignition using stratified combustible mixture

subject:
Stratified mixture
Direct numerical simulation
Localized forced ignition
Equivalence ratio
Karlovitz number

abstract: Localized forced ignition of turbulent stratified mixtures has been numerically analyzed based on three- dimensional Direct Numerical Simulations (DNS) for different values of Karlovitz number (Ka) corresponding to different turbulent combustion regimes. The initial values of turbulent fluctuations and the integral length scale of turbulence have been modified to bring about the change in Ka. The localized forced ignition is accounted by a source term in the energy transport equation which deposits energy over a time interval. It has been found that combustion takes place predominantly under a premixed mode of combustion following successful ignition. An increase in Ka has shown an increase in Minimum Ignition Energy (MIE) and has been shown to have adverse effects on the burned gas mass. Additionally, a stratified combustion mixture has been found to be a more favorable choice over homogeneous mixtures for a given turbulent ow condition for achieving a higher burning rate.


title: Controlling the Vienna rectifier using a simplified space vector pulse width modulation technique

subject:
PFC
Multi-level rectifier
Vienna rectifier
Soft switching
Space vector modulation

abstract: In this thesis, a simplified Space-Vector Pulse-Width-Modulation (SVPWM) technique for the Vienna rectifier is introduced to reduce the computational burden, the switching losses and the Total-Harmonic-Distortion (THD). Furthermore, the robustness of this modulation technique is tested under various faults through a 70 kW MATLAB/Simulink model and the results are validated through 1.2 kW prototype. The results reveal that the simplified SVPWM provides a low THD, unity Power-Factor (PF) and effective capacitor voltage balancing even after extreme faults.  This study introduces a multilevel Power-Factor-Correction (PFC) converter in a 2-stage configuration. The first stage is the Vienna rectifier which has a high boosting ratio. To overcome this issue, a high efficiency 4-switch converter is cascaded with the Vienna rectifier. This converter employs storage-less passive components and provides a Zero-Current-Switching (ZCS) for all of its switches. A description of the converter is first introduced followed by the simulation results.

abstract: University of Ontario Institute of Technology


title: Characterization of OmpT: An outer membrane vesicle protease Escherichia coli that attenuates blood coagulation.

subject:
E. coli-Escherichia coli
F-factor
OmpT-outer membrane protease T
OMVs-outer membrane vesicles

abstract:
Escherichia coli O157:H7 is an emerging food-borne and water-borne pathogen that belongs to
Enterohemorrhaghic pathogenic group of bacteria. E. coli O157:H7 colonizes the gastrointestinal
tract and is responsible for hemorrahagic colitis, renal failure, bloody diarrhoea, hemolytic
uremic syndrome, thrombocytopenia, hemolytic anemia and other systemic problems.
E. coli O157:H7 is responsible for outbreaks of Enterohemorrhaghic E. coli infections and
causes significant mortality and morbidity globally. Factor V (Mr-330,00Da) is a procofactor
that upon activation to FVa profoundly enhances thrombin generation and fibrin clot formation
as part of prothrombinase. The fibrin clot immobolizes the pathogen and allows the immune
system to target and destroy the bacterium. Our research has shown that pathogenic Escherichia
coli O86a:K61 secretes the protease OmpT as part of outer membrane vesicles (OMVs), which
inactivates coagulation Factor V and in so doing, induces a hemorrhagic state. To further
characterize the effect of OmpT on the coagulation, this study has employed a genetic approach
using wild type, an OmpT deletion mutant, and an over-expressing OmpT construct in
pathogenic E. coli O157:H7. Although the growth of the three strains in liquid culture was not
significantly different over time in nutrient rich media, OmpT over expression retarded cell
growth in nutrient deficient media (p<0.05). Wild type cells and OmpT over expressing cells
produced significantly larger numbers of different size ranges of outer membrane vesicles than
OmpT deletion mutant (p<0.05). Wild type cells and outer membrane vesicles prolonged both
the prothrombin time and activated partial thromboplastin time in normal human plasma, and this
effect was enhanced with OmpT over expressing cells and abolished in the OmpT deletion
mutant. Wild type cells and outer membrane vesicles inactivated Factor V, but not other factors
(fibrinogen, FII and FX), in normal human plasma to a 250kDa product and the effect was
increased in OmpT overexpressing strain and abolished in the OmpT deletion mutant. The effect
of OmpT was direct and did not involve the host plasminogen system. In summary, this research
indicates that OmpT has a role in OMV biogenesis and composition, and disrupting the
coagulation process and fibrin barrier formation during the host innate immune response and in
doing so may permit enhanced bacterial survival within host environments. The research will
also lead to a greater understanding of the mechanism of action of E. coli virulence factors and
positively impact healthcare environments through the development of novel and robust
vaccines, antimicrobial drugs, diagnostic methods, and medical treatments.


title: Thermal characterization and modeling of an energy storage system

subject:
CFD
Thermal characterization
Charging system
Lithium-ion batteries

abstract: The thesis reports a virtual design tool that was developed to predict and analyze thermal loads in an electric vehicle charging system. The tool was designed using computational fluid dynamics techniques and validated with experiments to provide a system-level view of the temperature profiles of all components and airflow patterns inside the charging system. The existing configuration of the charging system indicated that the cooling was capable of maintaining a maximum surface temperature of 35.61℃ for the lithium-ion batteries. Using the virtual design tool, the placement of the air conditioner and configuration of the battery fans were modified, resulting in an improvement in the cooling distribution of the batteries where the maximum surface temperature was decreased to 34.99℃. A novel method of quantifying battery surface temperatures through the use of a Rack Cooling Index was presented for examining the cooling effectiveness in the system.


title: The workplace writing experiences of EAL (English as an Additional Language) professionals: five case studies

subject:
ESL
Second language acquisition
Workplace writing
Workplace learning

abstract: A review of the literature on English second language (L2) writing skills reveals a need for more research on the workplace writing experiences of L2 professionals employed in English as an Additional Language (EAL) contexts. Through a case study approach involving a semi-structured interview, a think-aloud activity, and a questionnaire, this study gathered qualitative and quantitative data with the aim of gaining insight into the workplace writing practices, challenges, and strategies of five EAL professionals with developing workplace writing skills, employed in Toronto, Canada. The data were initially analyzed using a thematic analysis technique and further explored to identify interconnecting themes associated with the development of L2 workplace writing skills. Three factors were identified as influential in the development of the participants’ workplace writing skills: motivation, awareness of the role of self, and awareness of the role of others.


title: Social importance of recognizing the victimization for mothers of school shooters

contributor:
Downing, Steven
Cesaroni, Carla

subject:
Secondary victims
Mothers of school shooters
School shootings
Labelling theory
Social labels

abstract:
This paper presents various topics that contribute to understanding Sue Klebold, Monique
Lépine, Terri Roberts, Laurel Harper, and Parvinder Sandhu as secondary victims of school shooting homicides. With the application of Becker’s (1963) labelling theory, there is an opportunity to examine the potential ramifications these secondary victims suffer as the result of the shootings, in addition to examining if they are subjected to social labels.
By studying secondary victims of crime and the labels imposed on them, this study may be able to understand why such individuals suffer from mental illness and/or sociological drawbacks. The results of this study indicate that the social labelling of secondary victims is a social reaction to the victim’s behaviour and relationship with the offender. These victims are more likely to suffer from anxiety disorders such as Post-Traumatic Stress Disorder (PTSD).


title: Assessment of wastewater algae for use in biofuel production

subject:
Biofuel
Algae
Bacteria
Fatty acids
Feedstock

abstract: Although new technologies have allowed the attainment of previously untapped fossil fuels these practises are unsustainable and harmful to the environment. Part of the solution to ease the fuel burden is through renewable fuels derived from microalgae as they are a carbon neutral source of fuel. The aim of this research was to assess if algae derived from municipal wastewater sources could be potential biofuel feedstocks by assessing their growth and fatty acid accumulation. When comparing wastewater derived algae to culture collection strains there was no significant difference (p>0.05) in terms of growth rates under photoautotrophic and mixotrophic conditions. The strain Botrydiopsis B2N under mixotrophic (14mM glucose) possessed the highest growth rate (2.7x104 cells•L-1•day-1) of all the strains tested under the various conditions. It was noted that under mixotrophic growth (14mM glucose) non-axenic algae accumulated significantly higher concentrations of neutral lipids compared to the same algal strains under axenic conditions. The result of which is thought to be caused by bacteria creating a nutrient deprived media causing the algae to become stressed and accumulate fatty acids. Under mixotrophic growth (14mM glucose and 3mM acetate) the organic carbon in the media appeared to shift the composition of fatty acids in most cases increasing the likelihood of an even blend of saturated to unsaturated fatty acids.


title: Young adults’ understandings of their transition out of the child welfare system

subject:
Child welfare
Transition out of care
Care leavers
Intersectionality
Individualization

abstract: This dissertation examines care leavers’ first-hand experiences of negative outcomes through a theoretical lens. Regardless of multiple, intersecting identities and structural changes, youth in the Ontario child welfare system must navigate the same transition from the system to the larger community. This major life event and process involves a drastic change from full dependency on the child welfare system, which is a restricted context to full responsibility on care leavers with limited guidance to navigate a fluid context. There is increasing awareness that during this compressed process, care leavers experience numerous risks of negative outcomes. As a result, the Ontario government allocates funding for the child welfare system to promote a collective vision of support for youth and young adults to flourish. Nevertheless, there is limited evidence that care leavers benefit from investments. Drawing on one-on-one in-depth, semi-structured interviews with 21 young adults ages 19 – 27, this research found that care leavers were inadequately prepared for transition out of care, and after transitioning, they encountered poor outcomes in the following areas: education, employment, housing, mental health, criminal justice system, and social support networks. Thus, Kimberle Crenshaw’s intersectionality theory and Ulrich Beck’s individualization theory are used to construct a social justice lens (i.e., intersectional individualization) with the aim to enhance understandings of reasons why youth and young adults transitioning out of the child welfare system experience risk of poor outcomes. Utilizing this intersectional individualization lens, this study argues that while care leavers tried to reflexively navigate their transition, diverse, multiple, overlapping identities and structural changes heightened their vulnerability, marginalization, and risk of negative outcomes. Moreover, this study contributes a nuanced understanding that can inspire systems of power to take a social justice approach, which can mitigate the impact of transition out of the child welfare system. This dissertation concludes with implications for future research, theorizing, policy, and practice within this specific field.


title: Brønsted Acid-Catalyzed Reactions of Vinylboronic Acids and Benzhydryl Alcohols

subject:
Styrylboronic Acid
Benzhydryl Alcohol
Brønsted Acid
Catalysis
Alkenylation

abstract: The functionalization of benzhydryl alcohols is an approach to form important building blocks in organic synthesis. More specifically, the derivatization of benzhydryl alcohols to afford an alkene is a desired approach due to the wide variety of derivatizations applicable to 1,3,3-triphenylpropene derivatives. However, many approaches towards functionalization rely on harsh reaction conditions or the use of Lewis acid catalysts, which leads to low functional group tolerance. Herein, a methodology for the formation of 1,3,3-triphenylpropene derivatives through a Brønsted acid-catalyzed reaction of styrylboronic acids and benzhydryl alcohols is reported. The use of tetrafluoroboric acid diethyl ether complex (HBF4·OEt2) in substoichiometric amounts is desirable as it allows for the introduction of the desired alkene structural motif under less harsh conditions than the previously reported methodologies. Using milder reaction conditions results in a broader scope of benzhydryl alcohols and styrylboronic acids as starting materials.


title: Immunomodulatory effects of lactic acid bacteria on human intestinal epithelial cells and macrophages in the context of a pro-inflammatory challenge

contributor:
Forrester, Sean
Strap, Janice

subject:
Lactic acid bacteria
Cytokine production
Intestinal epithelial cells
Immunomodulatory activity

abstract:
Immunomodulatory effects of lactic acid bacteria vary with strain and may
vary with growth phase and medium. The ability of different lactobacilli
strains (Lactobacillus helveticus R0052, L. rhamnosus R0011, L.
rhamnosus GG) at different growth phases to modulate macrophage and
intestinal epithelial cell cytokine production following a pro-inflammatory
challenge was examined. Modulation of cytokine production by human
macrophage cell lines (U-937) and intestinal epithelial cells (HT-29) induced
by Tumor Necrosis Factor α was assayed by ELISA for interleukin-8 (IL-8).
Granulocyte-macrophage colony stimulating factor (GM-CSF) production
was assayed by ELISA in the HT-29 cell line. Strain-dependent differences
were observed in the ability of viable bacteria and spent de Mann-Rogosa-
Sharpe (MRS) broths from log versus stationary growth phase in HT-29 and
U-937 cells. Overall, variation in the immunomodulatory activity of these
lactic acid bacteria and spent broths reflects not only strain variation but
potentially also differences in growth phase and substrate.


title: Chronic toxicity of phthalates, biphenol and a Canadian bottled water stored under different light regimes using the Cnidarian Hydra Viridissima©

subject:
Bottled water
Dibutyl phthalate
Bisphenol A
Bis (2-ethylhexyl) phthalate
Hydra

abstract:
There is general concern whether human exposure to selected Canadian bottled
waters and the chemicals which may leach from them, could potentially cause deleterious
effects. This research was designed to determine whether exposures to bottled water and
plastic leachates caused toxicity to the freshwater Cnidarian Hydra viridissima (green
hydra). Three chemicals used in the production of polycarbonate and polyethylene
plastics, bisphenol A (BPA) and two phthalate esters: dibutyl phthalate (DBP) and bis (2-
ethylhexyl) phthalate (DEHP) along with one type of commercial bottled water were
investigated. One brand of bottled water was analyzed over four months (stored in light
and dark conditions) along with lab water similarly stored in glass, polycarbonate and
polyethylene bottles. Following 2, 4, 8 and 16 weeks in each of the two treatments, hydra
bioassays were conducted. Chronic toxicity tests were also conducted on the two
phthalates and BPA. The chronic toxicity tests showed that BPA caused effects on hydra
morphology and population at low doses and DBP and DEHP both showed signs of
hormesis.


title: Fast algorithm for joint unicast and multicast beamforming in large-scale systems

contributor:
Dong, Min
ShahbazPanahi, Shahram

subject: Unicast beamforming

subject: Multicast beamforming

subject: Optimal structure

subject: Largescale optimization

subject: Alternating direction method of multipliers (ADMM)

abstract: We consider a joint unicast and multi-group multicast beamforming problem for massive multiple-input multiple-output (MIMO) system with a large number of unicast users. We propose an alternating direction method of multipliers (ADMM)-based fast algorithm that efficiently obtains the beamforming solutions for unicast and multicast users to minimize the transmit power subject to quality-of-service constraints. Utilizing the optimal multicast beamforming structure obtained recently, we separate the original problem into unicast and multicast subproblems to be solved using the alternating optimization technique. We solved the unicast subproblem in closed-form by exploring the unicast beamforming structure, which reduces the computational complexity, substantially. For the multicast subproblem, we apply the successive convex approximation (SCA) method to solve it iteratively. Each SCA subproblem is then reformulated to the ADMM form, providing the closed-form update for the multicast subproblem. Simulation results show that the proposed algorithm achieves a near-optimal performance with low complexity for large-scale systems.


title: Design and implementation of an inductive power transfer system for wireless charging of future electric transportation

subject:
Electric vehicles
Charger
DC-DC converter
Inductive power transfer
Finite element analysis

abstract: The motivation of this thesis was to formulate clear design guidelines for fabrication and control of an efficient series-series resonant inductive power transfer (SS-RIPT) system for electric vehicle battery charging application. In meeting this objective, several critical deficiencies about the field of RIPT based EV chargers specific to stationary charging have been solved. Firstly, to increase the tolerance to misalignments, use of an unsymmetrical coil pair for the charger has been proposed. An unsymmetrical coil pair, in which the outer diameter of the primary and the secondary coils are kept equal, whereas the inner diameter of the secondary is kept larger compared to the primary counterpart gives the best performance in misalignment conditions. By employing this unsymmetrical coil-pair, a charging pad which shows the horizontal tolerance to misalignment equal to 71% of the pad diameter has been presented. Secondly, a very simple yet novel analytical design procedure has been submitted, adopting which, eliminates the bifurcation issue for the entire range of load and coupling variation and therefore requires no sophisticated control. Finally, a simplified mathematical model of SS-RIPT system has been proposed for primary side control of output voltage and current. All the proposed theories and analysis have been verified by a 3.6 kW prototype of the SS-RIPT based charger fabricated in the lab. A DC-DC efficiency of 91% for rated load condition is achieved for the designed charger. For partial load conditions (less than 50% of the rated load), the efficiency is 87%.


title: Changes in spinal posture, muscle activation, center of pressure and discomfort while standing with different footrest heights during a standardized computer task

subject:
Ergonomics
Footrest
Standing aid
Intervention
Low back pain

abstract: Standing aids are recommended for individuals who are expected to stand for prolonged periods of time in the workplace to reduce the risk of developing low back pain (LBP). The purpose of this study was to examine how footrest usage, and footrests of differing heights, affect measures of posture, muscle activation, weight distribution, centre of pressure, and discomfort while working at a standing workstation. Four standing positions were compared: flat ground stance, and standing with a low (10 cm), medium (20 cm) and tall footrest (30 cm). Using a footrest significantly altered lumbo-sacral angle, lumbar-to-thigh angles, gluteus medius and lumbar erector spinae muscle activity, and COPrange in the elevated limb. Discomfort increased over the 15 minute trial regardless of condition. The medium (20cm) footrest provided unique advantages over the other footrest heights and should therefore be recommended in situations where an absolute footrest height is preferred.


title: Quilting stories and embracing culture: an arts-informed narrative inquiry exploring the experiences of an older Chinese Canadian immigrant with depression

subject:
Chinese immigrant
Depression
Mental health
Narrative inquiry
Arts-informed methods

abstract:
Chinese immigrants tend to underutilize mental health services. Cultural and
linguistic barriers may discourage Chinese immigrants from accessing these services.
Yet, a paucity of qualitative research that explores the experiences of older Chinese
Canadian immigrants with depression exists in the mental health literature. This study
explored how older Chinese immigrants (age 55+) experience depression, and what their stories reveal about the sources of mental health support that they use. Using arts-informed
narrative inquiry methods, I conducted a series of five research sessions with a
co-participant from the Chinese Canadian community in the Greater Toronto Area.
Narrative patterns regarding identity, voice, and communication, as well as a prominent
narrative thread of relationship, emerged from my co-participant’s story. This study
illustrates the heterogeneity that exists within this group, and illuminates the value of a
person-centered and culturally safe approach to providing mental healthcare to older
Chinese immigrants with depression.


title: Development of a PSA-based safety assessment and management framework for nuclear-based hydrogen generation system.

subject:
Nuclear-based hydrogen production
Probabilistic safety assessment (PSA)
Safety instrumented system (SIS)
Fault tree

abstract: The nuclear-based Cooper-Chloride (Cu-Cl) thermochemical cycle a promising method for future large-scale hydrogen generation. The nuclear-based hydrogen generation leads to new challenge for system safety due to the complexity of the co-generation system. In this research, a PSA-based framework for safety assessment and safety management of the nuclear-based hydrogen generation system is developed to perform a risk-informed design for Cu-Cl cycle. Two major safety challenges, LOCA and the hydrogen accidents, are analyzed in details with the PSA-based safety management framework. The PSA study shows that nuclear risks are effectively reduced by the reactor safety system, while the major risk is the hydrogen accidents. Based on the safety assessment result, safety instrumented system (SIS) is designed to control the hydrogen accidents. Different SIS configurations are compared numerically, which demonstrate the advantages of PSA-based methodology in controlling the uncertainty of the safety study.


title: Assessing nearshore water quality and biological condition in the Kawartha Lakes using a community science approach

subject:
Nearshore zone
Water quality
Aquatic community
Community science
Land use

abstract: The Kawartha Lakes, located in south-central Ontario, are a popular tourist destination, with a growing permanent resident population. Consequently, land development in its watersheds continues, and the specific land-use – water quality relationships in this region are unknown. The nearshore zone is where land use has its first impacts on the lake, and provides vital habitat for most lake inhabitants at some point in their life cycle. Despite its importance, the nearshore zone is rarely monitored and further investigation is required to understand human impacts on the nearshore zone. My thesis aimed to elucidate the relationships between land use and the abiotic and biotic condition of the nearshore zone in the Kawartha Lakes. To examine Lake Scugog’s nearshore water quality patterns and relationship with land use, 12 volunteers collected water samples from spring to fall for three years. Land use had significant impacts on chloride at buffer scales and phosphorus at the sub-watershed scale. I also monitored the nearshore biotic community (phytoplankton, zooplankton, and macroinvertebrates) at eight sites in Lake Scugog. Two years of sampling found that macrophyte abundance significantly influenced the phytoplankton, zooplankton, and macroinvertebrate communities. During the pandemic restrictions in 2020, community scientists on 16 lakes collected monthly water samples from June-September. A subset of four lakes had nutrient data across 3-years (2019 - 2021), which allowed comparison of nutrient conditions before and during the pandemic. There were significant differences in water quality between watersheds and a notable impact of Lake Scugog on downstream lakes. There was not a significant impact of pandemic restrictions on nearshore water quality in these lakes. A focal study on Balsam, Cameron, Sturgeon, and Pigeon lakes involved nearshore water quality monitoring (2019 and 2021) and biological sample collection (2021). There was a separation of distinct water quality profiles that grouped Balsam and Cameron, and Sturgeon and Pigeon. Exploring relationships between land use, water quality, and the biotic communities I found that phosphorus was important for driving phytoplankton, zooplankton, and macroinvertebrate community abundance. Overall, these findings provide important information for lake managers in understanding the role of land-use and nearshore ecological condition in lake health.


title: Deep learning approach to discontinuity-preserving image registration

subject:
Image registration
Optimization
Deep learning
Convolutional neural networks
Chest CT

abstract: Image registration is an indispensable tool in medical image analysis. Traditionally, registration algorithms are aimed at aligning image pairs using regularizers to impose smoothness restrictions on unknown deformation fields. The majority of these methods assume global smoothness in the image domain, which pose issues for scenarios where motion discontinuities exist. Examples where local motion discontinuities happen are the sliding motion between adjacent organ tissues, and the pushing motion of the lungs against the chest wall during the respiratory cycle. Furthermore, an objective function must be optimized for each given pair of images. Thus registration of multiple image sets becomes very time-consuming and poorly scale with higher resolution image volumes. Using recent developments in deep learning, we propose an unsupervised learning-based image registration model. This model is trained over a loss function with a custom regularizer that preserves local discontinuities while simultaneously respecting the smoothness assumption in homogeneous regions of image volumes. In following a learning-based model, the image registration process can be completed within seconds, which is significantly quicker than optimization-based registration algorithms. The proposed model will be evaluated qualitatively and quantitatively on datasets of chest computed tomography (CT) 3D image volumes.


title: Real time safety verification in the process industry using fault semantic networks (FSN)

subject: FSN POOM BBN FDS IPL

abstract:
In the process industry, there are uncertainties associated with each variable, which might lead to process deviations and hazards. In order to accurately quantify the risks associated with these hazard scenarios, quantitative probability should be calculated. The process dynamically changes during plant operation, which requires continuous monitoring of process risks and real time safety verification. It is challenging to both dynamically and instantaneously estimate the risks for all faults and deviations. An FSN is introduced in this thesis to systematically and continuously estimate risks for all possible fault propagation scenarios.
Intelligent reasoning algorithms are proposed using a BBN to accurately estimate risks. An FSN is used to analyze causes and consequences of different faults using automated forward and backward propagation learning techniques. Real time safety verification is applied to each fault propagation scenario. The TE process is used to illustrate the proposed real time safety verification. An FDS experimental setup is used to study real life data.

abstract: University of Ontario Institute of Technology


title: Material properties and mechanical behaviour of large-scale additively manufactured multi-layered steels

subject:
Additive manufacturing
Stainless steel
Digital image correlation
Microstructure
Print pattern

abstract: Metal Big Area Additive Manufacturing is an additive manufacturing technique based on gas metal arc welding. The systems’ dual nozzle design prints two steels simultaneously; in this study, the test samples are made from AISI 410 stainless steel and AWS ER70S-3 mild steel. Three print patterns were designed to isolate the effects on the interface between the two materials. Deformation behaviour was analyzed by the use of two-dimensional digital image correlation. Nonhomogeneous strains and Lüders banding within the mild steel directly adjacent to the SS-MS interface were observed. There is a clear increase in strength close to the interface but no statistical change in strength between print patterns. Acicular ferrite/bainite were found close to the interface and allotriomorphic ferrite into the mild steel. A possible explanation for the changes in microstructure from is discussed by the use of electron diffraction spectroscopy, digital image correlation, microhardness, and electron backscatter diffraction.


title: Key performance indicators modeling for optimized microgrid configuration

subject:
Optimization
Microgrid
KPI modeling

abstract:
Distribution system is so vulnerable to failures. These failures can be the result of natural or manmade threats. Blackouts are one of the distribution systems failures. Many people can be affected by blackouts. Therefore, microgrids can be a suitable candidate to have a robust and secure distribution power system Microgrids can support the distribution systems while they are having problems. Microgrids can be operated in small levels such as hospitals, government buildings, hotels and airports.
Microgrids need to be studied in details. Models must be developed and analyzed to see the effect of the microgrid on the overall grid system. Microgrids can play a significant role in reducing the distribution systems dependency on the main grid as they have local distributed energy resources (DER) such as wind turbine, solar photovoltaic, diesel generator, gas engine, micro turbine, fuel cells, etc.
In order to evaluate microgrids, key performance indicators (KPIs) need to be studied. These performance indicators are essential to evaluate and optimize the configuration of microgrids. These KPIs are reliability indicators, environmental indicators, economic indicators, and power quality factors.
This research consists of two parts. The first part is optimizing a hybrid system design using GA (PV panels, wind turbines, and storage devices) by minimizing the system cost and maximizing the efficiency. The second part of the thesis focuses on KPIs in order to evaluate the performance of the microgrid. The proposed microgrid is modeled in MATLAB. Different scenarios are analyzed and the results are captured. In addition, AHP is used to evaluate the KPIs in a microgrid to determine which KPIs are the most important ones.


title: Restorative justice programs in Ontario: views of offenders

subject:
Restorative justice
Offenders
Process
Outcomes

abstract: Restorative justice has grown within the criminal justice system over the last 30 years. The current academic literature suggests that restorative justice programs provide many positive benefits for the offenders who participate in them; however, there is a lack of research to account for the subjective experiences of program participants. Using qualitative inquiry, the current thesis sought to understand better the meaning, purpose, and impact of restorative justice programs from ten adult offenders participating in one of two restorative justice programs in Southern Ontario: restorative conferencing and victim-offender mediation. Results highlight how offenders report gaining access to the programs, how they describe the programs, significant features of the programs, and long-term impacts of the programs. Recommendations to enhance the meaningfulness for the offenders as well as policy recommendations and areas for future research are discussed.


title: The many faces of Rob Ford: the representation of politician deviance, dishonesty and denial

subject:
Rob Ford
Corruption
Incompetence
Political scandal
Media representations

abstract: The discourse surrounding recent Canadian politics has involved the misbehaviour of Toronto’s former mayor, Rob Ford. Much of the information the public received about the antics of Ford is derived from media representations. The current inquiry sought to understand the treatment of Ford by the media to explore the messages the public receives regarding politician deviance. This was established through the creation of a 45 event timeline and a content analysis of the articles in the newspaper, Toronto Star that discussed each of the timeline events. The findings suggest that the journalists frame Ford as being incompetent most of the time, corrupt some of the time and a street level criminal occasionally. These frames are created through media narratives and strengthened through the inclusion of apparent perceptions of important community stakeholders.


title: Vehicular infotainment forensics: collecting data and putting it into perspective

subject:
Digital forensics
Internal vehicle components
Embedded devices
Infotainment systems
Vehicular forensics

abstract: In today’s transportation system, countless numbers of vehicles are on the road and later generations have become mobile computers. Vehicles now have embedded infotainment systems that enable user-friendliness and practicability with functions such as a built-in global positioning system, media playback device and application interface. Smartphones and laptops can connect to them through Bluetooth and WiFi for all sorts of utilities. This enables data flow between a user’s device and the infotainment system and because of this interaction, data remnants are kept on these embedded devices. It is important to determine what type of data is stored long term since this information reflects a user’s activity and potential personal information. In terms of forensics, this data could be used to solve criminal activities if a vehicle was suspected of being an accessory to a crime; raising general awareness about this topic is important due to the potential sensitive information circulated. This main objective of this thesis is to demonstrate what types of information are stored on infotainment systems, how it can be acquired and the implications and contributions of the collected data in relation to the overall field of digital forensics.


title: Design, analysis and optimization of novel photo electrochemical hydrogen production systems

subject: Photochemical Electrochemical Hydrogen Energy Chloralkali

abstract:
Hydrogen is a green-energy carrier with a high heat of combustion. If obtained from renewable sources, it could be the ultimate and environmentally benign solution for the future energy requirements. This thesis presents the candidate’s research on the photochemical hydrogen production cycle, motivations and objectives, literature survey, thermodynamic modeling, exergoeconomic modeling, electrochemical modeling, statistical modeling and preliminary results of the photochemical research. The process selected for the present study is known as the “chloralkali process”. The main objective of this research is, in this regard, to develop a hybrid system that produces hydrogen by photo chemically splitting water and neutralizing the by-products (i.e. hydroxyl ions) into a useful industrial process. To be more specific, the objective of this present study is to develop a system that combines photochemical hydrogen production with electrochemical chlorine and sodium hydroxide production in a photo electrochemical chloralkali process. Initially, a series of experiments are performed by using an electric power supply. These initial experiments are followed by photo electrochemical experiments, experiments with salt water, experiments without hole scavenger material and solarium experiment.
The results of electrochemical experiments show that the concentration of brine in the anolyte compartment and the concentration of electrolyte in the catholyte compartment do not affect the rate of chlorine and hydrogen production. The applied voltage, reactor temperature, and current density have a significant effect on the rate of hydrogen production. The optimal brine concentration is 225 g/L and the optimal electrolyte concentration is 25g/450ml. The increasing temperature reduces the solubility, thus increasing the rate of hydrogen production. Also, increasing the electrode surface area in contact with the working fluid increases the rate of hydrogen production.
During the photo electrochemical experiments, three different process parameters are studied, namely light intensity, catalyst concentration, and applied voltage. Using statistical models and experimental data, correlations for the production rate of products are developed. Energy and exergy efficiencies are calculated to assess the performance. An optimization study for photo electrochemical experiments is performed in order to find the optimal catalyst concentration. Using the optimal catalyst concentration from the photo electrochemical experiment results, experiments with salt water in catholyte are performed. The results show that salt concentration does not have any significant effect on the rate of hydrogen production. During the photo electrochemical experiments, it is observed that applied voltage has a significant effect on the rate of photochemical hydrogen production. This fact is further explored by performing experiments without hole scavenger material. The results show the continuous production of hydrogen. Ultimately, this means that a solid electrode can replace the hole scavenger material.
Energy, exergy, and exergoeconomic models for a heliostat based hybrid system are developed. A radiation model is coupled with a thermodynamic model in order to predict the rate of hydrogen, chlorine, and sodium hydroxide production for a given light intensity at a particular time. The parameters of the radiation model are set to simulate two varied weather conditions-namely a clear sky and a turbid sky environmental setting. Toronto is assumed to be a place where photo electrochemical chloralkali plant is located. The result shows that the maximum intensity occurs at noon time with the surface angle of 22° in an environment with a clear sky. The cost of hydrogen is calculated from the exergoeconomic model. The average annual cost for the hydrogen based on this model is calculated to be 0.7$/kg for a clear sky environment and 1.3$/kg for a turbid sky environment.
To find the minimum required potential, the electrochemical model is developed. The parametric study of different processing parameters shows that the brine concentration and electrolyte concentration do not have significant effect on required cell potential. Current density, temperature, and distance between electrodes, however, have a significant effect on cell potential. The results of the electrochemical model are consistent with the electrochemical experimental results.


title: Mathematical modelling of the plunger pump operation with numerical methods for simulating the flow across the valve

subject:
Plunger pump operation
Modelling valve dynamics
Immersed boundary method
Navier-Stokes equations

abstract:
Plunger pumps are needed for heavy duty sludge pumping at wastewater treatment
facilities. America's leading pump manufacturer Wastecorp Inc. brought
their plunger pump problem to us in late 2009. It was found that when the

ow rate reaches a critical value, the plunger pump starts to generate a clicking
noise.
A one-dimensional model was built for studying the
ow of a typical plunger
pump operation. The velocities and pressures are calculated at certain interesting
locations. Pressure jumps have been found while opening or closing the
valves. The valve motion is then modeled with considerations to its geometry.
The results show that as the plunger speed reaches a critical value, the valve
moves more rapidly and more likely to hit the wall and generates a noise. We
also provide a methodology to study the
ow across the valve in higher resolution.
A  nite-di erence approach to the Navier-Stokes equations are presented
with the immersed boundary method.


title: Enablers and barriers of suicide risk assessments in inpatient and emergency department settings: a scoping review

contributor:
Rudoler, David
Martin, Krystle

subject:
Suicide
Self-harm
Suicide risk assessment
Inpatient
Mental health

abstract: According to past mental health reports, the occurrence of suicide within inpatient healthcare facilities ranges between 1.0–4.5/1000 patients amongst North American, European, Australian and Chinese hospitals each year. As the risk of inpatient suicide continues to rise, tools such as suicide risk assessments may be useful in identifying at-risk patients. The current literature places a considerable amount of focus on validating suicide risk assessment tools. However, there is limited research on the implementation of these tools within inpatient facilities. This scoping review investigated the existing mental health literature surrounding suicide risk assessments to identify barriers and enablers to implementation of suicide risk assessments. MEDLINE and PsycINFO were systematically searched in April 2021, resulting in the inclusion of 52 articles. The Consolidated Framework for Implementation Research (CFIR) was employed to code and analyze implementation enablers and barriers. The main themes that emerged from this scoping review included: interprofessional collaboration amongst healthcare disciplines; perceptions of healthcare providers regarding risk screening; feasibility of risk screening; and training and education of healthcare providers. By unveiling both enablers and barriers to implementation, these results may guide decision-makers in determining the best course of action to effectively implement suicide risk assessments within inpatient facilities.


title: Frequency and predictors of tonsil surgery

subject:
Predictor
Frequency
Tonsil surgery
Prevalence
Tonsillectomy

abstract:
This thesis assesses the frequency of tonsil surgery and examines its predictors. Tonsil surgery is a common procedure which carries both advantages and disadvantages. The study begins with a systematic literature review of published articles which address the frequency and predictors of tonsil surgery worldwide. Using the data collected from a survey conducted on 6,363 high school students in the United Arab Emirates (UAE), the prevalence and predictors of tonsil surgery in this population are then examined.
In relation to the systematic review, a search strategy and inclusion and exclusion criteria lead to 11 relevant papers that were appraised by two reviewers. Findings suggest that age, geographical region, and race are predictors of tonsil surgery. However, there is conflicting, insufficient, or limited evidence for the association between tonsil surgery and each of sex, household income, parental educational levels, number of siblings, environmental tobacco smoke, asthma, allergies, serum Immunoglobulin E level, high body mass index, middle ear infections, upper respiratory tract infections, Down syndrome, and prematurity.
Using data from the UAE, our case study suggests that tonsil surgery is associated with nationality, maternal educational level, pesticide/insecticide, indoor humidity, and hay fever symptoms. However, after adjusting for potential confounders, findings related to multivariate analysis (binary logistic regression) suggest that nationality is the only predictor of tonsil surgery and that nationals of other Gulf Cooperation Council countries are more likely to undergo tonsil surgery. Additionally, adding interaction terms to the regression model reveals that seafood consumption and pesticide/insecticide exposure have interactions with nationality.
To conclude, this present work proposes age, geographical region of residence, and nationality (race) as predictors of tonsil surgery. However, further studies are needed to reassess other potential predictors with insufficient evidence. Furthermore, since each type of tonsil surgery may have a unique set of predictors, it is important to separately identify the predictors of each type of tonsil surgery. Additionally, there is a need for studies that separately assess and identify the predictors of each indication (a disease treated by the surgery) for tonsil surgery. Comparing the predictors of tonsil surgery with the predictors of indications for tonsil surgery may help to determine the reasons for the disparities in the frequency of tonsil surgery among different populations.


title: Improving diabetic self-management using Glucose Buddy.

subject:
Diabetes
Glucose Buddy
Self-management
Ease of use
Technology acceptance model

abstract: Diabetes is a chronic condition that requires regular ongoing monitoring. This quantitative descriptive study looks at utilizing the application “Glucose Buddy” designed for diabetic patients, available on Apple devices, and identified if the application is easy to use for any type of user and the security of the application to protect potentially sensitive health data. The navigation and ease of use of any application should be simple for any type of user (Bay & Ziefle, 2005). The study only required that the individual was able to interact and cognitively accept the application. Results show that 91% found the application easy to use and navigate without a tutorial. Our results indicate that the application is beneficial for newly diagnosed patient’s as it provides a graph format for viewing and allows them to enter in basic data related to their diabetes.


title: Identifying metabolic indicators of phytoplankton and comparing the temporal changes in algal community composition in two Lake Ontario areas of concern

subject:
Phytoplankton
Algal blooms
Lake Ontario
Area of concern
Metabolomics

abstract: Freshwater algal blooms transition into harmful algal blooms (HABs) when cyanobacteria produce toxins that impact ecosystem health. The point at which algal blooms transition into HABs is not fully understood, but I believe that the transition can be predicted by combining molecular and community-level information. This study consisted of ten weeks of sampling in 2020 from August to October in Hamilton Harbour and the Bay of Quinte, two Lake Ontario areas of concern (AOCs). Phytoplankton genus composition was obtained via microscopy and water quality was assessed. Metabolomics were performed using liquid chromatography tandem mass spectroscopy (LC-MS/MS) to identify changes in metabolites over time. The results from this study identified taurine, serine, and glycine in large amounts in both locations and that phytoplankton community composition is primarily affected by nitrates, total phosphorus, and turbidity. These findings will improve our understanding of these AOCs as well as the behaviour of phytoplankton overall.


title: A numerical study of the effects of inhomogeneous media in diffusion weighted imaging

contributor:
Lewis, Greg
Aruliah, Dhavide

subject:
Apparent diffusion coefficient
Diffusion MRI
Kurtosis
Mathematical models of diffusion

abstract: Diffusion Weighted Imaging (DWI) -a common Magnetic Resonance Imaging (MRI) technique - is used to infer material properties of tissues from the average diffusion of water molecules over brief time intervals. In particular, the Apparent Diffusion Coefficient (ADC), a measure of the magnitude of diffusion within tissues, can be derived from the MR signal under the assumption of homogeneous medium. Unfortunately, the complex structure of a typical volume element of physiological tissue contains many types of cells separated from extracellular space by semi-permeable barriers and is thus far from homogeneous. In this thesis, we define an idealized tissue model as a system of cells separated by non-uniformly spaced semi-permeable membranes and extracellular space. Finite-difference solutions of the associated PDE model can be used to compute a Displacement Probability Density Function (DPDF). Having numerically computed the DPDF it is possible to simulate the intensity of the MRI signal and, from it, compute the ADC as in a real Diffusion Weighted-MRI experiment. The ADC is measured by averaging the second moments of the DPDF. Finally, we investigate the changes in the ADC in an inhomogeneous model by including higher order moments of the DPDF and we discuss the possible advantages of these alternative definitions.


title: Evaporative drying of cupric-chloride droplets in a thermo-chemical cycle of hydrogen production

subject:
Spray drying
Hydrogen
Cu-CI cycle

abstract:
In this thesis, new empirical correlations that predict the behaviour of Cupric-Chloride
droplets undergoing spraying and drying processes are developed. Cupric-Chloride is a chemical
compound with the formula CuCl2 that is present as slurry or aqueous solution within the
Copper-Chlorine (Cu-Cl) thermo-chemical cycle for generation of hydrogen. An experimental
study examines the effects of inlet air and liquid temperatures, pressure, concentration, nozzle
diameter, and liquid flow rate on the outlet air temperature, particle size, particle size
distribution, morphology, moisture content, bulk density, and flowability.
The analysis examines a single droplet of CuCl2 solution in a continuum drying media. The
validation of the model involves comparisons with experimental data from previous studies
of different fluids based on non-dimensional analysis. The study provides new information
about the effects of different concentrations of water in the CuCl2 slurry drying at low to
moderate air temperatures.Analytical correlations of heat and mass transfer are developed for the
aqueous solution, subject to various drying conditions. The analysis is performed for moist air in
contact with a sprayed aqueous solution of Copper (II) Chloride Dihydrate [CuCl2 ·(2H2O)].
Validation of the model is performed by comparisons with experimental results.


title: Reconsidering the 'new' penology: Risk management, dangerous and judicial decision-making.

subject: New penology

subject: Risk management

subject: Actuarial assessment

subject: Dangerousness and judicial decision-making

abstract: As a result of the prevailing sense that ‘nothing works’ and the proliferation of risk oriented concerns in the criminal justice system, the current penal era has been characterized as a “new penology.” According to Malcolm Feeley and Jonathan Simon (1992), this period is identified by the priority of risk management, the use of actuarial risk assessments and the growing need for system efficiency. In this study, discourse analysis was performed on judgments from dangerous offender hearings that took place in Ontario in the year 2010 in order to assess the extent to which the concepts of the new penology have infiltrated the process of judicial decision-making in Canada. Consistent with other research on frontline criminal justice practitioners, results indicate that, while judges do increasingly employ a risk-oriented and actuarial approach, they have not abandoned the individualistic considerations and rehabilitative ideals that characterized earlier penal practices. Implications of this finding and directions for future research will be discussed.


title: Design and development of an interactive autonomous monitoring and surveillance drone

subject:
Drone
Design and development
Machine vision
Machine learning

abstract: This thesis describes the design and development of the novel autonomous UAV that has powerful GPU unit and potential sensing capability. It can run ROS (Robot Operating System) and compatible with packages developed under ROS. With the waterproof enclosure, it can land on the surface of water to do measurement of water parameters. Meanwhile, a human machine interaction mechanism using gesture recognition is developed and implemented for the developed drone to understand human commands. A novel way of image processing using depth information is developed for distance measurement. Meanwhile, a standard calibration method is applied and a vision-based object identification is developed and implemented in the on-board computer. It mainly achieves the function of licence plate identification and recognition. It includes a deep natural network and an OCR modular to achieve the identification, segmentation and recognition. The results showed the achievement of 95% success rate.


title: A parallel adaptive method for pseudo-arclength continuation

subject: HPC Arclength Parallel Computing

abstract:
We parallelize the pseudo-arclength continuation method for solving nonlinear systems
of equations. Pseudo-arclength continuation is a predictor-corrector method where the
correction step consists of solving a linear system of algebraic equations. Our algorithm
parallelizes adaptive step-length selection and inexact prediction. Prior attempts to parallelize
pseudo-arclength continuation are typically based on parallelization of the linear
solver which leads to completely solver-dependent software. In contrast, our method is
completely independent of the internal solver and therefore applicable to a large domain
of problems. Our software is easy to use and does not require the user to have extensive
prior experience with High Performance Computing; all the user needs to provide is the
implementation of the corrector step. When corrector steps are costly or continuation
curves are complicated, we observe up to sixty percent speed up with moderate numbers
of processors. We present results for a synthetic problem and a problem in turbulence.


title: Board game accessibility for persons with visual impairment

contributor:
Mirza-Babaei, Pejman
Kapralos, Bill

subject:
Board game
Accessibility
Visual impairment
Heuristic evaluation
Assistive technology

abstract: Despite the huge popularity and benefits of traditional board games, they present serious accessibility issues to players, particularly those with visual impairments, due to the heavy use of visuals to communicate gameplay information. Limited research investigating the inherent issues present in board game elements and in the potential solutions to these issues has been conducted so far. In this thesis, an in-depth investigation in the field of board game accessibility for those with visual impairment is conducted, investigating three main aspects: i) the inherent accessibility issues of game components and mechanics, ii) the reliability of board game guidelines for the identification of accessibility issues, and iii) the development of a digital assistive technology for board game gameplay. The findings of this thesis are discussed and compiled, in order to provide a general guide regarding the development or adaptation of accessible board games.

abstract: University of Ontario Institute of Technology


title: Teachers' views of their technology-focused preservice education program

subject:
Preservice education
Technology
Teacher
Education
TPCK

abstract: This study explores the effectiveness of a technology-focused preservice education program by interviewing practicing teachers who have graduated from the program. The views of the teachers are examined with reference to Darling-Hammond‟s (2006) theoretical framework for teacher education, and Mishra and Koehler‟s (2006) TPCK model. The findings indicate that the teachers who participated in this study value the aspects of their preservice program that they can use in their teaching practice. There is also evidence that a preservice program which is infused with technology enables preservice teachers to adopt new pedagogies using technology into their own teaching practice. The intent of this study is to identify areas where the preservice program may be strengthened and to promote further research into technology integration in preservice education.


title: Effective modeling of advanced filters and multiplexing networks

subject:
Computer-aided design
Microwave filter modeling
Multiplexers
Multiplexing networks;
Neural networks

abstract:
Microwave filters and multiplexers are widely used in all types of electronic systems. This research focuses on advanced filters and multiplexers for applications in communication satellites with stringent requirements and specifications. Conventional modeling techniques are typically either based on fast but inaccurate circuit models, or based on full-wave electromagnetic (EM) simulation, which is accurate yet time-consuming. To overcome the limitations of conventional methods, this thesis presents two modeling techniques for microwave filters to enhance the efficiency and accuracy in both near-band and wide-band simulations.
In the first method, a hybrid model is constructed with an EM analyzed I/O coupling junction, which is close to the multiplexer manifold, and a circuit model representing the rest of a channel filter. Since only one junction is EM simulated, neural networks (NNs) can be applied in the hybrid models to facilitate efficient modeling of the filter over a large frequency range. As demonstrated with a temperature compensated Ku-band multiplexer and a high power dielectric resonator filter, both in-band response and out-of-band spurious mode behavior of channel filters are captured in the hybrid models.
In the second modeling method, the entire filter is segmented and each junction is EM simulated. By only preserving the necessary information of the generalized scattering matrix (GSM) of each critical junction of the filter, the data size of each junction is dramatically reduced, which makes training and testing of a NN model possible. All the well-trained NN models are connected through transmission lines. The resulting filter model consists of only NNs and transmission line models, and is therefore very fast. Conventional dual mode cylindrical waveguide filter and high-power dielectric resonator filters are used to demonstrate this method. The efficiency and accuracy of the modeling method are proved by comparing the simulation results of the proposed model to the results from full-wave simulation and measurements. A good agreement is observed for both near-band and wide-band results.
Both methods present in the thesis are proven to be more efficient than conventional circuit models or full-wave EM models.


title: JoVA-hinge: joint variational autoencoders for personalized recommendation with implicit feedback

contributor:
Szlichta, Jarek
Salehi-Abari, Amirali

subject:
Recommender systems
Deep learning
Variational Autoencoder
Hinge based loss function

abstract: Recently, Variational Autoencoders (VAEs) have shown remarkable performance in collaborative filtering (CF) with implicit feedback. These existing recommendation models learn user representations to reconstruct or predict user preferences. However, existing VAE-based recommendation models learn user and item representations separately. This thesis introduces joint variational autoencoders (JoVA). JoVA, as an ensemble of two VAEs, simultaneously and jointly learns both user-user and item-item correlations and collectively reconstructs and predicts user preferences. Moreover, a variant of JoVA, referred to as JoVA-Hinge, is introduced to improve recommendation quality. JoVA-Hinge incorporates pairwise ranking loss to VAE's losses. Extensive experiments on multiple real-world datasets show that our model can outperform state-of-the-art under a variety of commonly-used metrics. Our empirical experiments also confirm that JoVA-Hinge offers better results than existing methods for cold-start users with limited training data.


title: Development and analysis of a high temperature electrolyser for the Cu-Cl cycle for hydrogen production

contributor:
Dincer, Ibrahim
Rosen, Marc A.

subject:
High temperature electrolyser
Cu-Cl cycle
Hydrogen production
Nuclear energy
Exergy

abstract: A number of thermochemical cycles have been investigated to produce hydrogen from water. However, most of these cycles operate at over 800°C. The relatively lower temperature (550°C) requirement and use of inexpensive chemicals make the copper-chlorine (Cu-Cl) thermochemical cycle a promising process for hydrogen production. Building a large scale hydrogen production facility based on this cycle presents some challenges that need to be resolved. This thesis addresses the challenges of the Cu-Cl cycle by incorporating high temperature electrolysis to propose and assess four novel configurations of the Cu-Cl cycle. Four novel Cu-Cl cycles using high temperature electrolytic step for hydrogen production are proposed and thermodynamically assessed. In addition, a novel hybrid Cu-Cl cycle for the co-production of hydrogen and copper using copper waste is proposed and assessed thermodynamically. An experimental investigation is made to establish the feasibility of the high temperature electrolytic step. The results suggest that using high temperature electrolysis in the Cu-Cl cycle may be beneficial as it provides a higher energy efficiency than some similar cycles reported in the literature. A detailed electrochemical model is developed to study the J-V characteristics for the proposed electrolyser (a solid oxide electrolyser based on proton conducting electrolyte). The developed model includes all the major losses namely activation, concentration and ohmic losses. Furthermore, energy and exergy analyses are also carried out. The value of energy and exergy efficiencies of the proposed electrolyser are 41.1% and 39.0%, respectively. Simulation results show that at 1073 K, P=100.325 kPa and J=1000 A/m2, 1.6 V is required to produce 1 mole of hydrogen which is 0.3 V (approx.) less than the voltage required by the high temperature steam electrolyser (based on proton conducting electrolyte) operating at the same conditions (T=1073 K, P=101.325 kPa and J=1000 A/m2) suggesting that using the proposed electrolyser a new avenue may be open for high temperature electrolysis for hydrogen production, potentially with a low electrical energy requirement. The cost of hydrogen production from the three step Cu-Cl cycle (Scheme 4) is $4.18 per kg of hydrogen. In addition, two nuclear based integrated systems for the production of electricity, fresh water and hydrogen are proposed and assessed. System 1 is more efficient than System 2 in terms of energy and exergy efficiencies and has lower exergy destructions.


title: “…she hit me and we stopped, she was yelling and screaming at me”: An exploration of the perceptions, identities and stigma of men and domestic violence

subject:
Domestic violence
Men
Masculinity
Identities
Stigma

abstract: Domestic violence is a prevalent and important global social issue. This thesis is unique as it seeks to mobilize knowledge of male perceptions and experiences of domestic violence by giving voice to a rather silenced, invisible, and often neglected group of individuals. Through face-to-face conversations with nine men with ties to a community organization located within the Greater Toronto Area (GTA), a qualitative conversation and thematic analysis was conducted. Through this interpretivist framework, I closely examine their lived experiences and perceptions of social reality as these men navigate the labels of masculine identities, stigma and social construction of domestic violence. Their perceptions inform us of their experiences with the criminal justice system and access to service(s). Core themes that emerged from the data are: (a) Masculine Identities, (b) Stigma Management, and (c) Barriers to Service. Practical implications, recommendations, future research and limitations in dealing with this neglected population is discussed.


title: Haptic teleoperation of mobile manipulator systems using virtual fixtures.

subject:
Haptic
Teleoperation
Mobile-manipulator
Virtual fixtures

abstract:
In order to make the task of controlling Mobile-Manipulator Systems (MMS) simpler, a
novel command strategy that uses a single joystick is presented to replace the existing
paradigm of using multiple joysticks. To improve efficiency and accuracy, virtual fixtures
were implemented with the use of a haptic joystick. Instead of modeling the MMS as a
single unit with three redundant degrees-of-freedom (DOF), the operator controls either the
manipulator or the mobile base, with the command strategy choosing which one to move.
The novel command strategy uses three modes of operation to automatically switch control
between the manipulator and base. The three modes of operation are called near-target manipulation
mode, off-target manipulation mode, and transportation mode. The system enters
near-target manipulation mode only when close to a target of interest, and allows the operator
to control the manipulator using velocity control. When the operator attempts to move
the manipulator out of its workspace limits, the system temporarily enters transportation
mode. When the operator moves the manipulator in a direction towards the manipulator’s
workspace the system returns to near-target manipulation mode. In off-target manipulation
mode, when the operator moves the manipulator to its workspace limits, the system retracts
the arm near to the centre of its workspace to enter and remain in transportation mode.
While in transportation mode the operator controls the base using velocity control.
Two types of virtual fixtures are used, repulsive virtual fixtures and forbidden region virtual
fixtures. Repulsive virtual fixtures are present in the form of six virtual walls forming a
cube at the manipulator’s workspace limits. When the operator approaches a virtual wall,
a repulsive force is felt pushing the operator’s hand away from the workspace limits. The
forbidden region virtual fixtures prevent the operator from driving into obstacles by disregarding
motion commands that would result in a collision.
The command strategy was implemented on the Omnibot MMS and test results show that
it was successful in improving simplicity, accuracy, and efficiency when teleoperating a
MMS.