title: Effects of chronic exposure to ibuprofen and naproxen on Florida flagfish (Jordanella floridae) over one complete life-cycle

subject: Ibuprofen Naproxen NSAID Life-cycle Flagfish

abstract:
Nonsteroidal anti-inflammatory drugs (NSAIDs) are a class of drugs prescribed to relieve pain, fever and inflammation, and are among the most commonly consumed medications in Ontario. Approximately 70% of the ingested dose is excreted unchanged or as an active metabolite, much of which reaches the surface waters of lakes and rivers. NSAIDs function through the inhibition of cyclooxygenase (COX), an enzyme present in two isoforms in the body; the constitutively expressed COX-1 and the inducible COX-2. Traditional NSAIDs like ibuprofen inhibit both isoforms with little selectivity while newer variants such as naproxen preferentially inhibit COX-2. Both COX isoforms share a high similarity between humans and fish creating a potential for off target effects to exposed aquatic organisms. This research investigated the chronic effects of waterborne exposure to 0, 0.1, 1, 10 and 100 μg/L of a nonselective and selective NSAID (ibuprofen and naproxen, respectively) on Florida flagfish (Jordanella floridae) over one complete life-cycle. Chronic exposure concentrations were selected by performing a short term experiment which examined the hatchability of flagfish eggs using continuous semi-static exposure conditions. Growth, survivability and reproductive endpoints were assessed in the life-cycle study. A concentration-response relationship for both NSAIDs was detected during the first 28 days post-hatch, resulting in increased body length for F1 fish and their offspring with increasing concentrations. Exposure to 0.1 μg/L of both ibuprofen and naproxen resulted in a decrease in egg fertilization providing an experimental LOEC (lowest observable effect concentration) of 0.1 ug/L and NOEC (no observable effect concentration) of < 0.1 ug/L for both ibuprofen and naproxen based on the reproductive endpoint. This indicates that either NSAID has the potential to affect
the reproductive success of flagfish at concentrations at or below those commonly found in the environment.


title: Coded caching for cache-aided communication and computing with nonuniform demands

subject: Coded caching

subject: Nonuniform demands

subject: Memory-rate tradeoff

subject: Heterogeneous code distributed computing

subject: Optimization

abstract: In this dissertation, we consider the caching system of multiple cache-enabled users with nonuniform demands. We thoroughly characterize the structure of the optimal cache placement of the coded caching scheme (CCS).We show there are at most three file groups in the optimal placement and obtain the closed-form solution in each file grouping case. A simple algorithm is developed to obtain the final optimal cache placement, which only computes a set of closed-form solutions in parallel. We propose a tighter lower bound for caching and characterize the file subpacketization in the optimal CCS. Upon obtaining the optimal placement of the CCS, we characterize the memory-rate tradeoff for caching with uncoded placement. Focusing on the modified coded caching scheme( MCCS), we formulate a cache placement optimization problem to obtain the optimal placement. We present two lower bounds for caching with uncoded placement and compare them with the MCCS to characterize the memory-rate tradeoff and provide insights. We extend our study to accommodate both nonuniform file popularity and sizes and characterize the exact memory-rate tradeoff for two users. We then study the memory-rate tradeoff for decentralized caching. We formulate the cache placement optimization problem for the decentralized modified coded caching scheme (D-MCCS). To solve this non-convex problem, we develop a successive Geometric Programming (GP) approximation algorithm and a two-file-group-based low-complexity approach. We propose a lower bound for decentralized caching and compare it with the optimized D-MCCS to characterize the memory-rate tradeoff in special cases. Beyond caching problems, we consider the coded distributed computing (CDC) with arbitrary number of files of nonuniform popularity. We formulate a mixed-integer linear programming (MILP) problem that jointly optimizes the mapping and shuffling strategies to minimize the shuffling load. To solve this generally NP-hard problem, we propose a two-file-group-based low-complexity approach that achieves close shuffling load as conventional branch-and-cut method which has high computational complexity.

abstract: University of Ontario Institute of Technology


title: Computational and laboratory investigations of a model of blood droplet flight for forensic applications

contributor:
Aruliah, Dhavide
Qureshi, Faisal

subject:
Bloodstain
Forensic
Computational
Laboratory
Blood flight

abstract:
We present a three-dimensional, forward model of blood droplets in
ight. The proposed
model is based on a set of ordinary di erential equations (ODEs) incorporating viscous
drag and gravitational forces. We validate the model against laboratory experiments
in which a mock crime scene is constructed. The experiments consist of a ballistics
gel containing transfer blood or porcine blood shot by a riot ball from a paintball gun
constituting a simulated bloodletting event. The experiments are captured using highspeed
stereo camera pair from which three-dimensional trajectories can be extracted
using tracking software. The long-term goal is to develop an accurate framework for
forensic Bloodstain Pattern Analysis (BPA).


title: Cloning and characterization of AdeMNO RND efflux pump of Acinetobacter baumannii

subject:
RND efflux pump
Antibiotic resistance
Multidrug resistant microorganism
Acinetobacter baumannii

abstract: Acinetobacter baumannii is an opportunistic pathogen which has been implicated in a variety of nosocomial infections among immunocompromised patients worldwide. Recently, Multi-drug resistant (MDR) isolates of A. baumannii have been isolated from military personnel returning from service in Iraq and Afghanistan. Antibiotic resistance of A. baumannii has limited the number of active antibacterial, making very difficult to treat these types of infections. This work investigated the role of Resistance-Nodulation-cell Division (RND) efflux pumps in the antibiotic resistance mechanism of A. baumannii. Expression of six different RND pumps was analyzed in clinical isolates of A. baumannii. A novel RND family pump, AdeMNO, was found to be present in a majority of isolates. The adeMNO operon was cloned, sequenced, and characterized using the single copy gene expression system in an efflux sensitized surrogate Pseudomonas aeruginosa strain. Antibiotics, trimethoprim, chloramphenicol, and clindamicin were identified as the substrates of this pump. In order to understand the mechanisms of regulation of adeMNO operon, a putative regulator belonging to the lysR-family was identified, cloned, and sequenced from the upstream region of the operon. Promoter regions of the adeMNO operon were also sequenced from various clinical isolates and sequence polymorphisms identified that could be implicated in the regulation of adeMNO expression.


title: The impact of restricted ration and chemical stressors on Rainbow trout (Oncorhynchus mykiss) and American flagfish (Jordanella floridae)

subject:
Pharmaceuticals
Multigenerational
Reproduction
Restricted Ration

abstract: This research aimed to increase the understanding of the impact of multiple factors including both environmental and chemical stressors and their effects on fish survival, growth, and reproduction. Rainbow trout (Oncorhynchus mykiss) were used to assess the impact of restricted feed on acute toxicity and it was found that prior feeding regime is unlikely to affect short-term toxicity results. These findings are important when considering the potential implications in both setting regulatory guidelines, and in the natural environment. American flagfish (Jordanella floridae) were used to assess the impact of environmentally relevant concentrations of ibuprofen, naproxen, and 17 α- ethinylestradiol (EE2) alone and in mixture on both reproduction and subsequent sensitivity to offspring. Both a short-term reproduction test, and multi-generational study were used to assess a variety of endpoints. The partial life-cycle study noted a significant decrease in fertilization as a result of exposure to 0.1 μg/L naproxen, and 10 ng/L EE2, as well as a significant increase in egg production as a result of exposure to 0.1 μg/L ibuprofen. The multi-generational study demonstrated a significant decrease in fertilization after exposure to the highest concentration of mixtures of ibuprofen, naproxen, and EE2 for both generations. There were also significant changes in egg production. In both studies subsequent toxicity to offspring was not altered significantly. Overall, there appeared to be reproductive impacts related to pharmaceutical exposure either via either short-term exposure, or over multiple generations. Conducting studies that encompass both chemical and environmental stressors has always been challenging. In surface waters, wild fish may be exposed to numerous compounds over multiple generations with many different stressors and modifying factors. Thus, it is important to consider multiple factors together in order to understand the true scale of potential contaminant impacts on fish populations.


title: The effect of target language proficiency on deception detection among undergraduate students

subject:
Deception detection
Language proficiency
Discrimination
Bias

abstract: I examined the impact of targets’ language proficiency on observers’ lie detection accuracy, discrimination, bias, and confidence. Observers (N = 132) were randomly assigned to make deception judgments about targets (N = 56) from four proficiency groups (i.e., native, advanced, intermediate, and beginner English speakers). Overall, observers’ accuracy differed based on targets’ level of proficiency. Specifically, accuracy and discrimination were poorest when observers judged beginner English speakers compared to targets from any other proficiency group. Moreover, observers exhibited a truth bias only when they judged native English speakers. They were also more confident when detecting targets who were lie-tellers than truth-tellers. Implications and directions for future research were discussed in light of these results.


title: Evaluation of the effects of molten CuCl on corrosion resistant coatings

subject: Corrosion Diamalloy CuCl Immersion Molten

abstract:
The world is facing energy crisis and pollution problems. Clean and renewable energy resources are gaining popularity day by day. Hydrogen is considered as clean energy carrier which is present in on earth in abundance either in the form of water or other chemical. The target is to produce hydrogen by thermo-chemical decomposition of water. Cu-Cl cycle is selected and preferred on other cycles based on its low operating temperature and cost. Plans for the design and construction of a hydrogen production pilot plant using the CuCl thermochemical cycle are being proposed. Currently researchers are facing several challenges to bring this pilot plant in operation. One of the important challenges is to develop materials for the containment vessels and pipes that will encounter the highly corrosive and harsh environment produced by the molten salts at the high temperature of 5000C.
This research is done to evaluate corrosion resistant coatings. Different coating materials were tested in high temperature molten copper chloride environment to evaluate the coating performance. Super hard steel, Diamalloy 4006, YSZ (ZrO2 18TiO2 10Y2O3) and alumina are the candidate materials selected for corrosion test. High Velocity Oxy fuel and Air Plasma Spray are the coating methods used to coat the samples. Series of tests were conducted in the absence of oxygen in a specially designed apparatus. Temperature was selected 5000C, based on Cu-Cl cycle maximum temperature. Tests were conducted for 50 and 100 hours.
Six coating combinations of bond and ceramic coats were tested in this research. Results suggested that, combination of Diamalloy 4006 (Diamalloy, Diamalloy+YSZ, Diamalloy+Al2O3) performed much better than SHS combination (SHS, SHS+YSZ, SHS+Al2O3). All super hard steel coatings fell off completely. Diamalloy 4006 coatings survived for 100 hours on the walls of the sample but the sample tips corroded badly. Corrosion products along with the deposits of pure copper appeared on the samples, in most of the cases. The study showed that alumina and YSZ can prevent diffusion of molten salt if these coatings do not crack. It was concluded that porosity may be the issue of coating failure.
To investigate the issue of porosity, solid samples of coating material (alumina) was tested in CuCl environment. There was no change in shape, size, weight and appearance of these samples after hundred-hour immersion test. It was concluded that the porosity of coating layers has to be minimized to protect the underlying material.


title: Thermodynamic analysis of molten carbonate fuel cell systems

contributor:
Dincer, Ibrahim
Berg, Peter

subject:
thermodynamic analysis
molten carbonate fuel cell
exergy and energy analysis

abstract:
This study deals with the thermodynamic analysis of a molten carbonate fuel cell
(MCFC) hybrid system to determine its efficiencies, irreversibilities and performance.The analysis includes a performance investigation of a typical molten carbonate fuel cell stack, an industrial MCFC hybrid system, and an MCFC hybrid system deployed by
Enbridge. A parametric study is performed to examine the effects of varying operating
conditions on the performance of the system. Furthermore, thermodynamic irreversibilities in each component are determined and an optimization of the fuel cell is conducted. Finally, a simplified and novel method is used for the cost analysis of the Enbridge MCFC hybrid system.An exergy analysis of the hybrid MCFC systems demonstrates that overall
efficiencies of up to 60 % are achievable. The maximum exergy destruction was found in
components in which chemical reactions occur. In addition, the turboexpander is one of the major contributors to the overall exergy destruction of the system.
The cost analysis of the Enbridge system illustrates that by merging the importance
of “green” energy and rising costs of carbon offsets, this new technology could be a
promising solution and substitute for future energy supply.


title: Spatial sound and sound localization on a horizontal surface for use with interactive surface (tabletop) computers

subject:
Tabletop computer
Interactive surface computer
Audio interaction
Sound localization
Spatial sound

abstract:
Tabletop computers (also known as surface computers, smart tables, and
interactive surface computers) have been growing in popularity for the last decade
and are poised to make in-roads into the consumer market, opening up a new
market for the games industry. However, before tabletop computers become widely
accepted, there are open problems that must be addressed with respect to audio
interaction including: "What loudspeaker constellations are appropriate for tabletop
computers?" "How does our perception of spatial sound change with these different
loudspeaker configurations?" and "What panning methods should be used to
maximally use the spatial localization abilities of the user(s)?" Using a custom-built
tabletop computer setup, the work presented in this thesis investigated these three
questions/problems via a series of experiments. The results of these experiments
indicated that accurately localizing a virtual sound source on a horizontal surface is
a difficult and error-prone task, for all of the methods that were used.


title: Temperature dependent structural, electronic and optical properties of the Si(100) surface from first principles

subject:
DFT
Si(100)
Dimer
Optical response
Temperature

abstract: The results presented here were obtained using the local density approximation (LDA) to density functional theory (DFT), within the pseudo-potentials scheme. We present the results of the numerical simulations for the Si bulk and Si(100) surface; ab-initio molecular dynamics (AIMD) using the Car-Parrinello Molecular Dynamics formalism (CPMD) and Born-Oppenheimer Molecular Dynamics (BOMD), related vibrational states (surface phonons) by calculating the vibrational density of states (VDOS) using a harmonic and anharmonic approach, and the optical response of the Si bulk and Si(100) surface calculating the temperature dependent reflectance anisotropy (RA). The surface reconstruction and temperature stimulated dimer flip impacts the surface reconstruction dynamics, the surface band gap and the optical response. For the calculated optical response and phonon spectra real temperature dependent atomic motion has been incorporated into the numerical formalism explicitly. This allows us to calculate the above materials’ properties, and reach an agreement with experiment, at different temperatures.


title: Three dimensional heterogeneous finite element method for static multi-group neutron diffusion

subject:
Heterogeneous finite element method
Static neutron diffusion equation
Finite difference equations
Weighted residuals method

abstract: Because current full-core neutronic-calculations use two-group neutron diffusion and rely on homogenizing fuel assemblies, reconstructing pin powers from such a calculation is an elaborate and not very accurate process; one which becomes more difficult with increased core heterogeneity. A three-dimensional Heterogeneous Finite Element Method (HFEM) is developed to address the limitations of current methods by offering fine-group energy representation and fuel-pin-level spatial detail at modest computational cost. The calculational cost of the method is roughly equal to the calculational cost of the Finite Differences Method (FDM) using one mesh box per fuel assembly and a comparable number of energy groups. Pin-level fluxes are directly obtained from the method’s results without the need for reconstruction schemes.


title: Investigation of electrochemical and material properties of TiO2 nanostructures generated by pulsed laser ablation

subject:
Supercapacitor
Electrode
Pulsed laser
Machine learning

abstract: The most challenging feature of the supercapacitor is low energy density. The supercapacitor's low energy density can be improved by proposing new materials for electrodes, electrolytes, etc. This thesis presents a new method for fabricating electrodes in a supercapacitor structure. In this method, we use pulsed laser ablation with the theory of increasing the surface area of electrodes. Although this method can be applied in different materials, we use titanium as a low-cost and lightweight material in our experiments. We use electrochemical and physical properties to investigate the effectivity of this method in different ways. In the first phase, we analyzed the electrochemical and physical properties of TiO2 electrodes by changing one laser parameter. In the second phase, we propose inverse engineering to calculate input parameters to fabricate specific supercapacitors based on machine learning techniques. In the second phase, we compare the result for three different machine learning algorithms then pick one for the inverse engineering structure.


title: Conversion of a scroll compressor to an expander for organic Rankine cycle: modeling and analysis

subject:
Scroll compressor
Expander
Rankine cycle
Heat recovery
Heat engines

abstract: Conversion of a scroll compressor to an expander for organic Rankine Cycle: modeling and analysis


title: Direct Brønsted acid-catalyzed functionalization of benzhydryl alcohols and 2-ethoxytetrahydrofuran using potassium trifluoroborate salts

subject:
Brønsted acid
Organotrifluoroborates
Alkynylation
Alkenylation
Metal-free

abstract:
Metal-free transformations of organotrifluoroborates are advantageous since they avoid using frequently expensive and sensitive transition metals. Lewis acid-catalyzed reactions involving organotrifluoroborates have emerged as an alternative to metal-catalyzed protocols. However, these methods rely on generating unstable boron dihalide species thereby resulting in low functional group tolerance.
A Brønsted acid-catalyzed carbon-carbon bond forming methodology involving alkenyl- and alkynyltrifluoroborates and in situ generated carbocations has been developed. In the presence of HBF4, we have shown that organotrifluoroborates react with benzhydryl alcohols to afford alkenes and alkynes in good to excellent yields. This protocol features excellent atom economy since alcohols and organotrifluoroborates react in a 1:1 ratio. Functional group tolerance superior to Lewis acid- and metal-catalyzed approaches was demonstrated.
Furthermore, we were able to extend this method to 2-ethoxytetrahydrofuran which underwent direct substitution to afford functionalized furans in moderate to excellent yields. A variety of alkenyl- and alkynyltrifluoroborates readily participated in this transformation.


title: Performance improvement for robotic mechanisms by: synthesis design, dynamic balancing and adaptive control techniques

subject:
Robotics
Synthesis design
Dynamic balancing
Adaptive control

abstract:
Robotics have been used in many arenas, such as manufacturing, medical, and space. Currently, the use of robotics is limited with respect to performance capabilities. Improving the performance of robotic mechanisms is a main research area. In this thesis, performance improvement is achieved through the approaches of robotic mechanism synthesis design, dynamic balance, and adaptive control.
A novel three degrees of freedom hybrid manipulator is designed. After discussing the advantages of this new type of hybrid manipulator, the kinematic and Jacobian matrix of this manipulator are analyzed. The kinematic performances, which include stiffness/compliance and workspace, are then analyzed and optimized, and the multi-objective optimization on the compliance and workspace is subsequently conducted. The dynamics of the proposed manipulator are analyzed based on the Lagrangian method.
When robotic mechanisms move, because the center of mass is not fixed and angular momentum is not constant, vibration is produced in the system. Dynamic balance is normally achieved by using counterweight(s), counter-rotation(s) or damping methods. However, the problem is that the whole system will become heavier and have more inertia. It is here proposed that dynamic balancing can be achieved through reconfiguration, rather than using counter-devices, so that the system will not gain any unwanted weight. After designing a balanced single leg, the legs will be combined to synthesize parallel mechanisms, i.e. first dynamically balance a single leg by the reconfiguration method (decomposition) and then combine the balanced legs to synthesize the whole parallel mechanism (integration).
As the mechanism is reconfigured, the control system has to be reconfigured accordingly. One way to address the control system reconfiguration is by breaking up the control functions into small functional modules, and from those modules assembling the control system. A hybrid controller for serial robotic manipulators is synthesized by combining a proportional–integral–derivative controller and a model reference adaptive controller in order to further improve the accuracy and joint convergence speed performance. The results show that the convergence speed for the hybrid controller is faster than that of the MRAC controller. The hybrid and MRAC controllers are both better than that of the PID controller. Experimental system is developed to model and verify the correctness of a reconfigured control system.


title: Ready, Teacher One

subject:
Virtual reality (VR)
Head-mounted display (HMD)
Degrees of freedom (DoF)
Immersion
Presence

abstract: This study examines how French First-language teachers responded to virtual reality (VR) professional development in 2021 in the province of Ontario. The teachers used higher-end VR Oculus Quest 2 systems in a digital, polysynchronous, collaborative, virtual learning environment during eight fully-immersive teacher professional development sessions. The overall research by design model allowed the researcher and the teacher participants to address one of many gaps in the research on VR by investigating how three areas intersect: (1) teacher professional development, (2) immersive technologies, and (3) pedagogical design. The findings of this study suggest that teachers can interact in VR and collaboratively design immersive learning spaces to increase student engagement but that teachers require time and support to identify the pedagogical applications of VR spaces. Teachers working in VR can reduce physical distance and increase both collaboration and presence; this transforms the professional development experience beyond what was traditionally thought possible.


title: Determining the differences in effect of chromate, chromite and chromium picolinate in rainbow trout (Oncorhynchus mykiss) at environmentally relevant concentrations

subject:
Chromium
Metals
Proteomics
Toxicology
Ring of Fire

abstract: The Ring of Fire is a region in the James Bay Lowlands of northern Ontario that houses a rich deposit of chromite and is slated for mining development. The goals of this study were to better understand the relative effects of Cr6+ to Cr3+ in rainbow trout, identify potential protein biomarkers to distinguish between Cr6+ and Cr3+ exposure, and determine whether chromium picolinate (a commonly prescribed nutritional supplement) is beneficial or harmful to fish. Proteomic analysis on the fish plasma showed no difference in Cr6+ and Cr3+ exposure across all concentrations and between chromium species. Decreased abundance in proteins associated with hepatocellular carcinoma and cardiomyopathy were also observed. These proteins were Trim21, Slc8a1, Myh4 and Myh6. For all, decreased abundance is associated with adverse outcomes. We hope that this study will advance knowledge on chromium toxicity in fish and protect all that inhabit the Ring of Fire region of Canada.


title: The use of linear and nonlinear methods for evaluating balance on collegiate men’s and women’s ice hockey teams throughout a season

subject: Balance Linear Nonlinear Concussion Collegiate

abstract: If objective data from balance assessments are to be used in assessing player’s for returning to play, it is necessary to understand the in-season variability that can occur. The purpose of this work was to determine if the time evolving nature of these measures can reveal insights, that more effective return-to-lay guidelines can be stablished. Forty-six varsity ice hockey players participated during the 2014-15 season. All underwent baseline measurements and were tested ever 4 weeks throughout the season, plus one post-season session. Dependent linear (mean power frequency, mean velocity, and total excursion) and nonlinear (approximate entropy) measures were used to interpret force plate data. Linear and nonlinear measures both showed significant main effects of time. Monthly testing throughout the season demonstrated decreases in mean values for all measures with respect to baseline. In-season variability of balance postures recorded can be used when comparing concussed athlete’s baseline measures to post-concussion measures.


title: Detection of side-channel communication in a mobile ad-hoc network environment using the Hamming distance metric

contributor:
Liscano, Ramiro
Martin, Miguel Vargas

subject:
Side-channel
MANETs
Hamming distance
Detection

abstract: Side-Channel communication is a form of traffic in which malicious parties communicate secretly over a wireless network. This is often established through the modification of Ethernet frame header fields, such as the Frame Check Sequence (FCS). The FCS is responsible for determining whether or not a frame has been corrupted in transmission, and contains a value calculated through the use of a predetermined polynomial. A malicious party may send messages that appear as nothing more than naturally corrupted noise on a network to those who are not the intended recipient. A Hamming Distance (HD) difference between the FCS values of purposely corrupted and naturally corrupted frames is proposed as a metric for the detection of side channel communication. In theory, it should be possible to recognize purposely corrupted frames based on how high this HD value is, as it signifies how many bits are different between the expected and the received FCS values. It is hypothesized that a range of threshold values based on this metric exists, which may allow for the detection of Side-Channel communication across all scenarios. In order to achieve this threshold range, a calculation known as F-Score has been used. Several approaches to verifying the F-Score thresholds have been presented to verify this range, as well as the validity of F-Score itself such as: Receiver Operating Characteristic (ROC) curves, and Support Vector Machines.

abstract: University of Ontario Institute of Technology


title: Design of contactless capacitive power transfer systems for battery charging applications

subject: Wireless charging

subject: Wireless capacitive power transfer systems

subject: Resonant converters

abstract: The main aim of the thesis, is to develop a high power system for small and large air-gaps applications, concurrently possessing high efficiency. To tackle the problems stated, two modified converters where proposed. The first proposed topology could yield higher power transfer for small air-gap applications. The topology proposed exhibits better efficiency and has several advantages compared to the existing topologies for small air gap applications. The second topology is called the Dual LC topology, which reduces the voltage stress across the capacitive interface enabling the CPT system to be used for large air gap applications. The Dual LC topology showcases excellent efficiency for variation in air-gap and under misalignment conditions. In final section of this thesis, the CPT system is extended to charging an industrial electric vehicle (IEV). As the requirement of charging an IEV varies depending on its battery pack. The power flow and control for the CPT systems is implemented.


title: Mean girls in the press: a content analysis of two Toronto newspapers

subject:
Moral panic
Mean girls
Youth aggression
Newspapers
Canada

abstract:
Recent criminological scholarship characterizes media attention to aggressive
girls, or “mean girls,” as a moral panic, which is correlated with the creation of
increasingly punitive antibullying policies in North America. Content analysis was used
to uncover how news attention to youth aggression around the time of Reena Virk’s
murder contributed to this moral panic in Toronto newspapers. Results indicate that
Virk’s murder helped change the frequency and nature of news coverage of girls’
bullying. Reporting on girls’ bullying significantly increased and the dominant news
frame falsely presented girls’ bullying as a major and rising problem in schools. The
news coverage coincided with the development of more punitive Canadian youth
policies. Recommendations for future research, theoretical development, and media
practice are provided.


title: Development and characterization of chemical modifications for siRNA strand selection

subject:
siRNA
Strand selection
Chemical modifications
Gene therapy
Gene silencing

abstract: Small interfering RNA (siRNA) are non-coding, double-stranded RNA that enable efficient gene silencing through RNA interference (RNAi) mechanisms. The primary effector of RNAi is an RNA-guided nuclease, Ago2, which selects one of the two strands as a guide to form the RNA induced silencing complex (RISC). Incorporation of the antisense, rather than the sense, strand is crucial for potency and safety siRNA therapeutics. Thermodynamic stability, phosphorylation status, and nucleotide sequence play a role in canonical strand selection; however, chemical modifications can improve strand selection and activity. To evaluate the impact of novel chemical modifications on strand activity, an RT-qPCR-based target cleavage assay was developed and validated. Dose-response analysis highlighted the consequence of overdosing, as dosages over 8 pM (for our siRNA sequence) resulted in significant sense strand activity without any on-target benefit. This assay was then used to characterize strand activity for siRNAs carrying azobenzene linkers, propargyl linkers, triazole-bound folate linkers, cubane linkers, hydrophobic phosphotriester modifications, or a 5’ phosphorofluoridate. Antisense vs. sense strand profiles revealed that nucleic acid substitutions (linkers) tend to reduce overall potency, likely due to an altered helical conformation and impaired recognition, but can effectively limit sense strand uptake when placed within the central region. These non-nucleotidyl linkers lack key hydrogen bond interactions between the guide RNA and both Ago2 and target mRNA, which are important for orienting the mRNA for cleavage. Surprisingly, placing a folic acid linker at the sense 3’ end was highly effective at limiting 3’ activity. Hydrophobic phosphate triester modifications have been shown to facilitate carrier-free uptake and are well tolerated. Profiles revealed that small phenethyl linkers had a limited impact of strand activity while larger octadecyloxy hydrophobic tails were more deactivating, likely due to steric constraints. Lastly, phosphorofluoridate analogues were also developed for their first introduction to siRNA. They exhibited a limited impact on strand activity. This may be the result of enzymatic hydrolysis and replacement with a natural phosphate, or efficient uptake of the modification within Ago2.


title: Forensic analysis of unallocated space

subject:
Computer forensics
Fingerprint hash table
Bloom filter
Fragmentation
Fragmentation point
Registry hive files
Hive bin
Key cell

abstract: Computer forensics has become an important technology in providing evidence in investigations of computer misuse, attacks against computer systems and more traditional crimes like money laundering and fraud where digital devices are involved. Investigators frequently perform preliminary analysis at the crime scene on suspects‟ devices to determine the existence of any inappropriate materials such as child pornography on them and conduct further analysis after the seizure of computers to glean leads or valuable evidence. Hence, it is crucial to design a tool which is portable and can perform efficient instant analysis. Many tools have been developed for this purpose, such as Computer Online Forensic Evidence Extractor (COFEE), but unfortunately, they become ineffective in cases where forensic data has been removed. In this thesis, we design a portable forensic tool which can be used to compliment COFEE for preliminary screening to analyze unallocated disk space by adopting a space efficient data structure of fingerprint hash tables for storing the massive forensic data from law enforcement databases in a flash drive and utilizing hash tree indexing for fast searching. We also apply group testing to identify the fragmentation point of the file and locate the starting cluster of each fragment based on statistics on the gap between the fragments. Furthermore, in order to retrieve evidence and clues from unallocated space by recovering deleted files, a file structure based carving algorithm for Windows registry hive files is presented based on their internal structure and unique patterns of storage.


title: Development and demonstration of a high-performance Gaussian puff model for nuclear emergency training scenarios in unity game engine

subject:
Atmospheric dispersion
Emergency preparedness and response
Modelling
Training
Unity

abstract: Prompt decision making and implementation of protective actions in the event of a nuclear or radiological emergency require detailed preparations and training. Computer models provide an avenue to simulate the presence of radioactive sources and/or releases of radioactive material safely, but the calculations involved can be complex and time- consuming. Increasing computer processing power and advanced coding techniques allow for complex simulations to be performed in real time while maintaining a level of performance suitable for modern interactive applications. A real-time dispersion model with simulation time scaling has been developed that provides a platform for creating training scenarios for the emergency response decision making process for radiological and nuclear emergencies. This research explores the development of this Gaussian puff model capable of calculating high-resolution radionuclide deposition maps and is demonstrated in an interactive training application.


title: Automatic fault localization in concurrent programs using noising and search strategies

subject:
Concurrency
Java
Bug
Noise
Fault localization

abstract: Multithreaded programs can have considerable performance benefits over sequential programs. However, these advantages often come at a cost with respect to program understandability as well as testing and debugging challenges. To address these challenges we have developed CFLASH (Concurrency Faults Localized Automatically using Search Heuristics), an automatic fault localization tool for multithreaded Java programs. CFLASH utilizes a combination of noise-based code injection and a heuristic search algorithm to identify potentially faulty code sections containing concurrency bugs. We demonstrated the effectiveness of CFLASH by localizing concurrency faults in a set of benchmarked concurrent programs as well as student programs collected at Ontario Tech University.


title: Development of instruments to access physiological and physical neck pain risk factors

subject:
Laptop use
Reliability
Laptop questionnaire
Neck pain
Dual somatosensory evoked potentials

abstract:
Neck pain has the potential to result in altered afferent input to the central nervous system which may thereby result in altered sensorimotor integration and eventually further disability. One “at risk” population for neck pain may be university students, particularly given the growing use of laptop computers in the university setting. This thesis presents two pilot studies which aim to develop and assess instruments to use as screening tools for risk factors associated with neck pain.
The first study explores the environment in which university students utilize their laptop computers and the relationship to known risk factors for neck pain. A new questionnaire, The Student Laptop Use and Neck Pain Risk Questionnaire (SLUNPRQ) was created to measure the presence of risk factors known to increase the risk of developing neck pain. This questionnaire was piloted for reliability using test- retest measures. Results indicated that the SLUNPRQ had good reliability based on Cohen’s Kappa scores. A modified questionnaire was developed based on questions with either low reliability or ambiguous answers and is ready for further testing.
The second study sought to determine if dual somatosensory evoked potential (SEP) ratios changed with long term chiropractic care. This was part of the overall goal of finding neural markers that could identify those who are at risk for developing neck pain. This study sought to determine the feasibility of using dual SEPs to evaluate changes in neural markers of sensorimotor integration after 12 weeks of chiropractic care and demonstrated that dual SEPs shows potential as a marker to screen individuals at risk of neck pain as the SEP markers showed improvement after long term chiropractic care.


title: Integration of heterogeneous data types using self organizing maps

contributor:
Zhu, Ying
Pu, Ken

subject:
Data integration
Information structures
Self-organizing maps
Data cleaning

abstract:
With the growth of computer networks and the advancement of hardware technologies, unprecedented access to data volumes become accessible in a distributed fashion forming heterogeneous data sources. Understanding and combining these data into data warehouses, or merging remote public data into existing databases can significantly enrich the information provided by these data. This problem is called data integration: combining data residing at different sources, and providing the user with a unified view of these data. There are two issues with making use of remote data sources: (1) discovery of relevant data sources, and (2) performing the proper joins between the local data source and the relevant remote databases. Both can be solved if one can effectively identify semantically-related attributes between the local data sources and the available remote data sources. However, performing these tasks manually is time-consuming because of the large data sizes and the unavailability of schema documentation; therefore, an automated tool would be definitely more suitable. Automatically detecting similar entities based on the content is challenging due to three factors. First, because the amount of records is voluminous, it is difficult to perceive or discover information structures or relationships. Second, the schemas of the databases are unfamiliar; therefore, detecting relevant data is difficult. Third, the database entity types are heterogeneous and there is no existing solution for extracting a richer classification result from the processing of two different data types, or at least from textual and numerical data.
We propose to utilize self-organizing maps (SOM) to aid the visual exploration of the large data volumes. The unsupervised classification property of SOM facilitates the integration of completely unfamiliar relational database tables and attributes based on the contents. In order to accommodate heterogeneous data types found in relational databases, we extended the term frequency – inverse document frequency (TF-IDF) measure to handle numerical and textual attribute types by unified vectorization processing. The resulting map allows the user to browse the heterogeneously typed database attributes and discover clusters of documents (attributes) having similar content.
iii
The discovered clusters can significantly aid in manual or automated constructions of data integrity constraints in data cleaning or schema mappings for data integration.


title: Cluster techniques and prediction models for a digital media learning environment

subject:
Data mining
Neural networks
Custer techniques
Learning
Dimensionality reduction

abstract:
The present work applies well-known data mining techniques in a digital learning
media environment in order to identify groups of students based on their pro le. We
generate identi able clusters where some interesting patterns and rules are observed.
We generate a neural network predictive model intended to predict the success of the
students in the digital media learning environment. One of the goals of this study is to
identify a subset of variables that have the biggest impact in student performance with
respect to the learning assessments of the digital media learning environment. Three
approaches are used to perform the dimensionality reduction of our dataset.
The experiments were conducted with over 69 students of health science courses
who used the digital media learning environment.


title: Mechanisms by which exercise promotes cognitive function in both depressed and non-depressed individuals

contributor:
Murphy, Bernadette
Yielder, Paul

subject:
Exercise
Major depressive disorder
BDNF
Cytokines

abstract: Major depressive disorder (MDD) is a debilitating disease characterized by low mood, memory deficits, poor sleep quality and alterations in biochemical markers associated with neuroplasticity. Less than half of MDD patients receive an efficacious treatment, warranting the need for novel treatment strategies. Exercise as an add-on therapy is a promising approach shown to improve mood, however, its mechanism of action remains unknown. To advance our understanding of the mechanisms by which exercise affects brain function this thesis studied both healthy and MDD individuals. Study One used a functional magnetic resonance imaging (fMRI) subsequent memory paradigm to investigate the effects of an eight-week exercise intervention on neural function in healthy and MDD groups. FMRI results showed significant deactivation in the hippocampus and across several memory-associated regions in both groups suggesting a potential increase in neural efficiency. Study Two evaluated exercise as an add-on to antidepressant medication (ADM) and cognitive behavioural group therapy (CBGT) for MDD. Exercise led to a robust decrease in depression scores (p=0.007, d=2.06), with 75% of the patients achieving either response or remission compared to 25% of those who received ADM and CBGT only. Exercise also led to greater improvements in sleep quality (p=0.046, d=1.28), cognitive function (p=0.046, d=1.08) and plasma brain-derived neurotrophic factor (BDNF), p=0.003, d=6.46. Furthermore, BDNF was positively correlated with improvements in depression (p=0.002, R2 = 0.50) and sleep quality (p=0.011, R2 = 0.38). Study Three found that exercise for healthy, young adults did not improve cognitive performance or biomarkers, despite the neural changes seen in the fMRI study. Overall, this thesis demonstrates that exercise promotes neuroplasticity in both healthy and MDD patients, substantially improving mood and cognitive performance in MDD. Plasma BDNF levels and sleep quality appear to be good indicators of treatment response and potential biomarkers associated with the clinical recovery of MDD.


title: A longitudinal analysis of the chiropractic profession from 1996 to 2007

subject:
Chiropractic
Ontario
Health human resources
Health policy
Retention

abstract:
Aim: To explore the relative attractiveness of chiropractic in Ontario, Canada from 1996-2007.
Methods: We conducted a longitudinal cohort study using administrative registration data from 1996-2007. Stickiness and Inflow concepts acted as proxy measures for relative attractiveness. Survival analysis was employed to identify practitioner groups more likely to leave practice.
Results: Chiropractors grew from 1,955 to 4,185 from 1996-2007 in Ontario. Increases occurred in the proportions of female, and foreign-trained chiropractors. Stickiness indicators averaged changes of 0.29/year from 1997-2003, but from 2004-2007 the average was 8 times greater, at 2.42 points/year. Survival analysis showed that certain groups, like newer practitioners were at greater risk of leaving practice (HRR 1.33, p<0.05; CI 1.04-1.73). However, time-varying analysis showed a post-delisting, increase in profession-wide likelihood of leaving.
Conclusion: The chiropractic profession became less attractive in synchrony with government policy decisions. Following delisting in 2004, the likelihood of leaving practice increased for most chiropractors.


title: Changes in cannabis consumption behaviors in relation to policy and public health developments and respiratory health of emerging adults in Canada

subject:
Cannabis
Emerging adults
Legalization
EVALI
COVID-19

abstract: Cannabis use appears to be more common among emerging adults (EA) compared to other age groups in Canada. Substance use or misuse peaks during emerging adulthood and may be influenced by political and public health deviations. This study aimed to (1) examine trends in frequency and quantity of cannabis consumption among EA before and after: legalization of cannabis in Canada, the “e-cigarette or vaping product use associated lung injury” (EVALI) outbreak, and COVID-19; and (2) to examine sex-specific differences in cannabis use and associations with respiratory symptoms. There was a continuous and gradual increasing trend in quantity and frequency of smoking and vaping cannabis over time. Quantity and frequency of consumption was higher among males than females. Frequency of vaping only/dual consumption may be protective of respiratory symptoms among females. Increased consumption demonstrates a need for policy measures to address excessive use following political changes and during public health events.


title: Assessment of FLUENT CFD code as an analysis tool for SCW applications

contributor:
Harvel, Glenn
Pioro, Igor

subject:
CFD
FLUENT
SCW
Heat transfer
Bare tube

abstract:
Chosen as one of six Generation‒IV nuclear-reactor concepts, SuperCritical Water-cooled Reactors (SCWRs) are expected to have high thermal efficiencies within the range of 45 ‒ 50% owing to the reactor‟s high pressures and outlet temperatures. The behaviour of supercritical water however, is not well understood and most of the methods available to predict the effects of the heat transfer phenomena within the pseudocritical region are based on empirical one-directional correlations which do not capture the multi-dimensional effects and do not provide accurate results in regions such as the deteriorated heat transfer regime.
Computational Fluid Dynamics (CFD) is a numerical approach to model fluids in multidimensional space using the Navier-Stokes equations and databases of fluid properties to arrive at a full simulation of a fluid dynamics and heat transfer system.
In this work, the CFD code, FLUENT-12, is used with associated software such as Gambit and NIST REFPROP to predict the Heat Transfer Coefficients at the wall and corresponding wall temperature profiles inside vertical bare tubes with SuperCritical Water (SCW) as the cooling medium. The numerical results are compared with experimental data and 1-D models represented by existing empirical correlations.
Analysis of the individual heat-transfer regimes is conducted using an axisymmetric 2-D model of tubes of various lengths and composed of different nodes count along the heated length. Wall temperatures and heat transfer coefficients were analyzed to select the best model for each region (below, at and above the pseudocritical region). To neutralize effects of the rest of the tube on
that region, smaller meshes were used were possible. Two turbulent models were used in the process: k-ε and k-ω, with many variations in the sub-model parameters such as viscous heating, thermal effects, and low-Reynolds number correction.
Results of the analysis show a fit of ±10% for the wall temperatures using the SST k-ω model in the deteriorated heat transfer regime and less than ±5% for the normal heat transfer regime. The accuracy of the model is higher than any empirical correlation tested in the mentioned regimes, and provides additional information about the multidimensional effects between the bulk-fluid and wall temperatures.
Despite the improved prediction capability, the numerical solutions indicate that further work is necessary. Each region has a different numerical model and the CFD code cannot cover the entire range in one comprehensive model. Additionally, some of the trends and transitions predicted are difficult to accept as representation of the true physics of SCW flow conditions.
While CFD can be used to develop preliminary design solutions for SCW type reactors, a significant effort in experimental work to measure the actual phenomena is important to make further advancements in CFD based analysis of SCW fluid behaviour.


title: Synthesizing play: exploring the use of artificial intelligence to evaluate game user experience

subject:
Games user research
Human-computer interaction
User experience
Video games
Artificial intelligence

abstract: Digital games are a complex interactive medium providing a multitude of different experiences. The field of games user research (GUR) is dedicated to investigating and optimizing user experience in games. Such inquiries are of both commercial and academic importance, enhancing product quality and our understanding of human behaviour. A common GUR methodology is usertesting, where researchers gain insights from human users interacting with products. However, usertesting is expensive in terms of expert labour, time, and resource costs. To address these concerns, we developed PathOS, a free, open-source tool for game testing with AI agents. PathOS simulates player navigation in games using a basic model of human behaviour. We conducted an evaluation of PathOS with developers, finding that it provides valuable predictions of user behaviour in the iterative design process. Ultimately, we aim to give the game development community a useful and versatile augmentation to their testing processes.


title: A study of MHD and Monte Carlo simulations of high-current plasma beams in industrial applications

subject: Plasma beams simulation

subject: Magnetohydrodynamicas (MHD) method

subject: ANSYS Fluent

subject: Monte Carlo (MC) method

abstract: In recent years, high-current plasma beams have been widely applied in industrial applications. Computational approaches help us easily understand plasma properties. In this thesis, the high-current plasma beams are simulated using Magnetohydrodynamics (MHD), Monte Carlo (MC), and Integrated Hybrid MHD and MC (IMHDMC) methods. For the new MHD method, the pressure, velocity and density of the high-current plasma beams are obtained by solving the mass, energy and momentum conservation equations, together with Ohm’s law, Faraday’s law and Ampere’s law. For the new MC method, the MC algorithm and codes are developed to calculate the electron flux, heat and deposit energy based on the particle transport processes and collisions in magnetic fields. For the IMHDMC method, the density profiles of electron and argon ions are calculated in the MC modelling part and the temperature and Lorentz force are calculated in the MHD modelling part. The MHD, MC and IMHDMC methods are quantitatively and qualitatively verified by comparing the simulation results of the three methods with the real experiment data. The comparison and discussion between the MHD, MC and IMHDMC methods are presented from the theoretical and simulation aspects in detail.  The two specific cases have been briefly discussed: plasma gasification and fusion energy generation. This thesis is focused on developing new computational methods for high-current plasma beams to provide design and implementation references in industrial applications. The computational simulations help us understand the complex phenomena surrounding the high-current plasma beams and lead to better understanding of plasma dynamics involved in industrial applications.


title: Evaluating and improving collection tree protocol in mobile wireless sensor network

contributor:
Liscano, Ramiro
Heydari, Shahram

subject:
Collection Tree Protocol
Mobile WSN
Sensor nodes
Data delivery ratio

abstract:
There has been growing interest in the Mobile WSN applications where mobility is
the fundamental characteristic of the sensor nodes. Mobility poses many challenges
to the routing protocols used in such applications. In this thesis we evaluate the
performance of Collection Tree Protocol as applied in mobile WSN scenarios. The
simulation study shows CTP performs poorly in mobile scenario because of the
frequent tree re-generation resulting from node movements.
We compare Collection Tree Protocol with reactive ad hoc network routing
protocols. The simulation results show that collection tree protocol performs better
than reactive MANET protocols in terms of data delivery ratio and control
overhead under low traffic rates. The end-to-end delay obtained in case of reactive
protocols is also higher compared to that obtained when using CTP, which is due to
their route discovery process.
This thesis presents an improved data collection protocol Fixed Node Aided CTP
based on the analysis of CTP. The protocol introduces the concept of fixed aided
routing into CTP.
It is shown that our enhanced CTP outperforms CTP in terms of data delivery ratio
and control overhead chosen as performance metrics.


title: System for evaluating effects of immersion in molten copper chloride salts on corrosion resistant coatings

subject: Molten-CuCI Corrosion-resistance Coating Immersion-test High-temperature

abstract:
Hydrogen, as one of the best alternative energy carrier candidates, is easier to sustain than fossil fuel. Hydrogen demand has significantly increased as a clean energy carrier. The Cu-Cl cycle is one of the capable thermochemical cycles which is supposed to develop hydrogen production. Since this cycle has some high temperature stages, a study on these parts is essential to realize the entirety of the cycle.
This research is about designing a system to evaluate candidate coatings following an immersion test in molten CuCl at 500°C for a prolonged time. Medium carbon steel was selected as the base metal. There were six types of combination coatings applied to evaluate the corrosion resistance of the generated coatings during the molten CuCl exposure…

abstract: University of Ontario Institute of Technology


title: Vixen: a games user research tool for collection and interactive visualization of usertesting data

subject:
Games user research
Visualization
Usertest
Mixed-methods
Analytics

abstract:
Visualization techniques can facilitate the understanding and exploration of relationships in usertesting data. For example, data from players' in-game movement can be combined with interview data or questionnaire results. However, the process of amalgamation is not straightforward, because the underlying data often exists in different formats. Another challenge is making these visualizations simple enough to provide a quick overview for producers, but also detailed enough to be usable and practical for gameplay programmers. Hence, there is a need for an interactive visualization tool that can adjust data representation based on the nature and detail level of data required from different members of a development team. This thesis reports
development efforts on a tool that assists data collection and provides a dynamic and interactive representation of usertesting data. The thesis reports two studies to evaluate the effectiveness of the tool with game developers.


title: Cellulose biosynthesis inhibitors modulate defense transcripts and regulate genes that are implicated in cell wall re-structuring in arabidopsis

subject:
Cellulose
Microarray
Cell wall
Cellulose biosynthesis inhibitor

abstract:
The cell wall is a multifunctional structure which is implicated in plant growth and development as well as responding to any environmental changes including biotic and abiotic stresses. One of the practical approaches in cell wall integrity studies is the modification of the quality and quantity of particular cell wall components or destroying the specific step in cell wall synthesis pathway using Cellulose Biosynthesis Inhibitors (CBIs). In this case, chemical screen for swollen organ phenotype has proved to be an important technique to identify the genes that are directly or indirectly involved in cellulose biosynthesis.
In the present research, a number of synthetic CBIs were obtained through a chemical library screen from Chembridge Company for the root swollen phenotype which is believed to be the response to a defect in cellulose biosynthesis. Therefore, a genome-wide expression profiling based on Affymetrix ATH1 GeneChip arrays (contains 22810 probe sets) were applied to investigate the altered transcriptome of four different CBIs including CBI-15, 18, 22, and 27 and isoxaben in 5 day-old Arabidopsis thaliana seedlings. The results of this project revealed overlapped up and down-regulated genes as well as discriminate responses to each CBI. The most striking modification were found in genes involve in response to the stress as well as cell wall integrity and restructuring. Thus, the identification of regulated genes under CBIs treatment suggests a robust candidate group of genes that likely to be correlated to cell wall biosynthesis.


title: Investigation of an alternative sulfonated silane in ceramic carbon electrodes for fuel cell applications

subject:
Fuel cells
CCE
TEBS
TPS

abstract:
The fabrication of an ideal electrode material for fuel cell application that can maintain an
optimal water content in both low and high relative humidity (RH) conditions has been studied
by many research groups. Previous work by Eastcott et. al has shown great promise when using
sulfonated ceramic carbon electrodes (CCEs) on the cathode of a PEMFC in low relative
humidity (RH) environments though increased water retention. Through the sol-gel method the
use of tetraethylorthosilicate (TEOS) and a small amount of 3-(trihydroxysilyl) propane-1-
sulfonic acid (TPS) as the ionomer demonstrated increased porosity, better durability, and better
fuel cell performance at low RH when compared to the traditional Nafion ionomer material.
In this work the sulfonated CCE material developed by Eastcott and Easton will be
replaced with a more ion conductive sulfonated organosilane monomer component. TPS was
replaced with 4-(2-(trihydroxysilyl)ethyl) benzenesulfonic acid (TEBS) and mixed with TEOS
and compared to the previous TPS/TEOS system as well as the traditional Nafion ionomer
electrode. The sulfonated CCEs were characterized using BET surface area analysis,
thermogravimetric analysis, SEM, and TEM. The electrodes were then evaluated in both halfcell
and full cell environments. Half-cell data showed an increased ECSA with TEBS when
compared to the Nafion ionomer, while full cell data determined a decreased performance at both
high and low relative humidities through polarization curves when compared to the TPS/TEOS
and Nafion ionomers. The results obtained have determined that an optimization of the
sulfonated to unsolfonated ratio has to be altered in order to gain a performance similar to that of
the TPS based ionomer. The total silane loading was then decreased while the TEBS loading was
increased and this showed an increase in fuel cell performance more comparable to the
TPS/TEOS ionomer system.


title: Design and evaluation of a hybrid multi-task learning model for optimizing deep reinforcement learning agents

subject:
Deep reinforcement learning
Neural networks
Deep learning
Multi-task learning
Actor-critic

abstract: Driven by recent technological advancements within the artificial intelligence domain, deep learning has emerged as a promising representation learning technique. This in turn has given rise to the evolution of deep reinforcement learning that combines deep learning with reinforcement learning methods. Subsequently, performance optimization achieved by reinforcement learning intelligent agents designed with model-free based approaches were predominantly limited to systems with reinforcement learning algorithms learning single task. Such a model was found to be quite data inefficient, whenever agents needed to interact with more complex, rich data environments. This thesis introduces a hybrid multi-task learning-oriented approach for optimization of deep reinforcement learning agents operating within different but semantically similar environments with related tasks. Empirical results obtained with OpenAI Gym library-based Atari 2600 video gaming environment demonstrate that the proposed hybrid multi-task learning model is successful in addressing key challenges associated with the performance optimization of deep reinforcement learning agents.


title: Playing is creating with PlayTIME: introducing and evaluating a tangible UI-based interactive scenario prototyping system

subject:
Tangible user interface
Game design
Game prototyping
Augmented reality
Interactive scenario

abstract:
With traditional game prototyping activities, physical and digital game prototyping
tasks are commonly separate, often requiring iteration between the two and different
personnel to complete physical and digital tasks. In this thesis, we present PlayTIME:
a Tangible Interactive Media Environment for Game-Play, as a means to narrow the
gap between digital and non-digital game design techniques. The system is designed
to allow game designers to focus on physical prototyping while the computer digitalizes
real-world actions into a playable digital game. The current PlayTIME implementation
uses Tangible User Interfaces to facilitate specific functionalities in Unity,
a widely-used game engine. We hypothesized that using PlayTIME would improve
the game design experience for users. To test our hypotheses, we ran a user study
to evaluate the usability, creativity support and enjoyment of PlayTIME against the
usability, creativity support and enjoyment of Unity alone. We found that PlayTIME
had a significant effect on usability, but both qualitatively and quantitatively did not
show results better than Unity alone. We found that PlayTIME had an insignificant effect on creativity support. Finally, we found that users enjoyed PlayTIME
significantly more than Unity, citing that it is novel and makes design feel more like
play.


title: Predictive analytics for maintenance activities in nuclear power plants: a feasibility study

contributor:
Sankaranarayanan, Karthik
Harvel, Glenn

subject:
Nuclear power plants
Machine learning
Predictive analytics
Digitization and modernization
Engineering management

abstract: Nuclear power plants are known for their use of legacy systems and processes. As plants age, the amount of maintenance increases while resources remain finite, leading to unwanted delays, affecting the health of assets and increasing costs. To aid in the modernization and digitization of nuclear power plants, this work explores data driven methods, including statistical and machine learning techniques to predict target variables. Representative Naval Propulsion Plant data with variables similar to that in the nuclear industry are used as nuclear data is not available in the public domain. Experimental results confirm target variables can be predicted with relatively high accuracy, with Deep Learning methods harbouring the lowest relative error. Two frameworks are developed based on results to showcase how predictive analytics can be used in nuclear power plant maintenance. This work is a proof of concept informing stakeholders that data driven approaches are viable in reducing maintenance delays.


title: Exploring the acute affect of de-coupled batting drills on the gaze behaviour and decision-making of elite baseball players

subject:
Perceptual-cognitive skill
Representative learning design
High performance sport
Perception-action coupling

abstract: Expert batters utilize context-specific information and gaze behaviour to aid decision-making and performance. However, typical practice and warm-up activities often lack relevant context-specific information and visual cues that exist in competition. This study’s purpose was to examine if drills varying in competition representativeness have an acute influence on decision-making and gaze behaviour. Twenty-eight elite baseball athletes participated in one of four warm-up drills and subsequently predicted pitch information in an 18 pitch simulation over three progressively harder temporal occlusion conditions. Main effects of occlusion time, F = 5.43, 3.87; p = .01, .03, and playing level, t = 2.41, p = .02; F = 13.06, p = .003, were observed in decision-making and gaze behaviour analyses, but no statistically significant warm-up condition effects were noted. Players of advanced skill made more correct predictions and fixated on task relevant areas, which was amplified by earlier occlusion times. The lack of a warm-up condition effect may be explained by the athletes’ prolonged exposure to unrepresentative practice activities and their subsequent skill in recalibration at switching between tasks.


title: Getting comfortable in the zone with S3DComfortZone

subject: S3DComfortZone

subject: Visualization tool

abstract: This thesis explains the creation of S3DComfortZone; a visualization tool integrated into the development pipeline displaying the virtual comfort zones of stereoscopic 3D devices. This tool addresses the need for visualization information of unique comfort zones across multiple stereoscopic 3D devices.  The comfort zone is defined as a volume of space in which virtual objects would be perceived comfortable by the user.  The volume is influenced by unique hardware parameters as well as distance to the display. The result of two studies suggest the mathematical model of the comfort zone defined in past literature holds true and the S3DComfortZone accurately visualizes the comfort zone of stereoscopic 3D devices using the model.  The results of the study also suggest the device itself plays a factor in viewing 3D objects comfortably.  S3DComfortZone informs developers of comfort zone information of multiple devices in real-time empowering them to make informed decisions regarding content creation.


title: Development of a model to investigate the sustainability of Ontario’s future electricity supply through a dual life cycle lens

contributor:
Rosen, Marc A.
McKellar, Jennifer

subject:
Life cycle assessment
Electricity Forecast
Energy
Emissions
Costs

abstract: Since the turn of the century, greenhouse gas emissions and their climate related impacts have been studied with increased vigor. A tool that has gained popularity in supporting the reduction of emissions is life cycle assessment (LCA). This thesis proposes looking forward to using life cycle emissions and life cycle costs to determine which technologies can sustainably, both environmentally and economically, be used to meet Ontario’s future electricity demand. A model was developed to calculate the life cycle impacts based on the installed capacity of each generation technology and its respective life cycle factors. The model was validated against historical results and then used to generate several alternative scenarios. A case study was performed, showing how a researcher could use the model to explore shutting down nuclear in Ontario. This model can now be used by researchers to assess life cycle impacts of electricity generation in Ontario and other jurisdictions.


title: Modeling and multi-objective optimization of a photovoltaic-thermal based multigeneration system

contributor:
Rahnamayan, Shahryar
Dincer, Ibrahim

subject:
Solar energy
Photovoltaics
PVT systems
Optimization
Energy

abstract:
In this thesis, a novel multi generation integrated system is introduced, analyzed and optimized. It consists of GaAs based PV (Photo-Voltaic) arrays connected in series. Light is being concentrated on those arrays using lenses or mirrors. Concentrated light increases the cell temperature significantly. The cell is cooled down using a heat transfer fluid. This heat is being transferred to an organic Rankine cycle which not only produces electricity but also produces hot water for domestic applications. The organic Rankine cycle is also coupled with quadruple ammonia water absorption chiller. A part of the net electricity is used a PEM electrolyzer which produces hydrogen. So, using a single heat source, four useful commodities are produced, namely electricity, hot water, cooling, and hydrogen.
An integrated thermal model is developed to analyze this system. Five parameters, namely pressure in primary loop, pressure and temperature of organic Rankine cycle, pressure and temperature of ammonia water chiller system are varied in order to investigate their effects on energy and exergy efficiencies, cost of electricity, enviro economic parameter and on different exergoenvironmental factors. The results indicate that the PV array should be tilted at 30˚ this will give maximum radiation intensity on the surface of PV array. I-V (Current and Volt) curves shows that increasing the radiation intensity increases both the current and voltage. For sake of analysis, the system is developed for Toronto, ON, Canada. At a concentration factor of 15 in a 100 cell PV array, 196.2 V and 8 A can be achieved at a radiation intensity of 1000 W/m². Similarly, increasing the radiation intensity can increase the cell temperature up to 700 K. The maximum calculated energy and exergy efficiencies are 46% and 40.5%, respectively.
Three objective functions are developed using the data obtained from parametric study namely exergy efficiency, cost of electricity ($/kWs) and exergoenvironmental impact coefficient.
These objective functions were optimized using a genetic algorithm called NSGA-II. I have a multiple solutions which is called Pareto-front. The results shows that the optimum efficiency is
38.14%, optimum cost of coefficient of electricity is 13.4 cents/kWh and optimized
exergoenvironmental impact coefficient is 2.6.
The multigeneration energy system discussed in this thesis and similar other alternatives (with renewable energy sources) can significantly contribute in addressing world energy needs and related challenges (e.g., human wealth, human welfare and environmental impact).


title: Computational fluid dynamic investigations of flow through an aged CANDU pressure tube

subject:
Nuclear
CANDU
Pressure tube
CFD
Fuel channel

abstract: Single-phase, isothermal computational fluid dynamics simulations of twelve simplified CANDUTM 37M fuel bundles sitting in both as-received and aged pressure tubes were performed with Hydra in this work. The predicted coolant flow behaviour of two cases were compared in order to investigate the impact of pressure tube deformation (sag and diametral expansion) on coolant flow. The boundary conditions and material properties are representative of normal operating conditions in a high-powered channel of the Darlington Nuclear Generating Station. Rigorous mesh and turbulence model sensitivity analyses have been performed in this work. It has been determined that pressure tube deformation has a significant impact on coolant flow behaviour, whereby up to 25% of flow bypasses the fuel. The reduced flow within the subchannels of the fuel bundles impacts the coolability of the fuel.


title: Exergoeconomic analysis and optimization of organic Rankine cycles

subject: Exergy Exergoeconomic Rankine Organic Optimization

abstract:
Heat sources such as biomass, industrial waste heat and solar thermal provide the
potential to produce renewable environmentally low impact electricity. Using these
resources efficiently within economic constraints is important for viability of these
systems. This thesis explores a regenerative organic Rankine cycle for use in low
temperature heat sources. A Bitzer model scroll expander is used for the prime mover for
the system. This expander has a reliable model in which thermodynamic analysis can be
done. Various working fluids are explored to investigate which one will provide the most
power output and efficiency within system constraints. Using optimization, each fluid is
tested within physical constraints for optimal operating conditions using system exergy
efficiency as the objective function. An exergoeconomic analysis is performed to predict the
cost rate of electricity of the system and is compared to current contract rates from the
Ontario Power Authority. Dimethyl ether shows promising results with a system exergy
efficiency of 11.76% and system energy efficiency of 2.84% at a source temperature of
120℃. The degree of superheat and pressure ratio are used as the independent variables in
the optimization. Highest isentropic efficiency for the expander is 29.22%, showing large
potential for improvement. Electricity cost rates for the system assuming 20 year life are
0.132 $/kWh to 0.197 $/kWh depending on the fuel input cost for dimethyl ether. At the
current state the system shows merit with large potential for improvement in the
expander.


title: Multi-dimensional modeling of transient transport phenomena in molten carbonate fuel cells

subject:
Molten carbonate fuel cell
Mathematical modeling
Dynamic response
Transport phenomena
Start-up process

abstract:
Molten carbonate fuel cells (MCFCs) have become an attractive emerging technology for
stationary co-generation of heat and power. From a technical perspective, dynamic operation has
a significant effect on the fuel cell life cycle and, hence, economic viability of the device.
The scope of this thesis is to present an improved understanding of the system behaviour at
transient operation that can be used to design a more robust control system in order to overcome
the cost and the operating lifetime issues. Hence, a comprehensive multi-component multidimensional
transient mathematical model is developed based on the conservation laws of mass,
momentum, species, energy and electric charges coupled through the reaction kinetics. In
essence, this model is a set of partial differential equations that are discretized and solved using
the finite-volume based commercial software, ANSYS FLUENT 12.0.1. The model is validated
with two sets of experimental results, available in open literature, and good agreements are
obtained. The validated model is further engaged in an extensive study. First, the MCFC
behaviour at high current densities or oxidant utilization, when the mass transfer becomes
dominant, is investigated using peroxide and superoxide reaction mechanisms. In brief, both
mechanisms predicted the linear region of the polarization curve accurately. However, none of
these mechanisms showed a downward bent in the polarization curve. A positive exponent for
the carbon-dioxide mole fraction is probably essential in obtaining the downward bent (“knee”)
at high current densities which is in contrast to what has been reported in the literature to date.
Next, a sinusoidal impedance approach is used to examine the dynamic response of the unit
cell to inlet perturbations at various impedance frequencies. This analysis is further used to
determine the phase shifts and time scales of the major dynamic processes within the fuel cell.
Furthermore, numerical simulation is utilized in order to investigate the underlying
electrochemical and transport phenomena without performing costly experiments. Results
showed that the electrochemical reactions and the charge transport process occur under a
millisecond. The mass transport process showed a comparatively larger time scale. The energy
transport process is the slowest process in the cell and takes about an hour to reach its steady
state condition.
Furthermore, the developed mathematical model is utilized as a predictive tool to provide a
three-dimensional demonstration of the transient physical and chemical processes at system startiv
up. The local distribution of field variables and quantities are presented. The results show that
increasing the electrode thickness provides a higher reaction rate, but may lead to larger ohmic
loss which is not desirable. The reversible heat generation and consumption mechanisms of the
cathode and anode are dominant in the first 10 s while the heat conduction from the solid
materials to the gas phase is not considerable. The activation and ohmic heating have the same
impact within the anode and cathode because of their similar electric conductivity and voltage
loss. Increasing the thermal conductivity of the cathode material will facilitate the process of heat
transport throughout the cell. This can also be accomplished by lowering the effects of heat
conduction by means of a cathode material with a smaller thickness.
In addition, a thermodynamic model is utilized to examine energy efficiency, exergy
efficiency and entropy generation of a MCFC. By changing the operating temperature from 883
K to 963 K, the energy efficiency of the unit cell varies from 42.8 % to 50.5 % while the exergy
efficiency remains in the range of 26.8% to 36.3%. Both efficiencies initially rise at lower
current densities up to the point that they attain their maximum values and ultimately decrease
with the increase of current density. With the increase of pressure, both energy and exergy
efficiencies of the cell increase. An increase in this anode/cathode flow ratio lessens the energy
and exergy efficiencies of the unit cell. Higher operating pressure and temperature decrease the
unit cell entropy generation.


title: Enhancing parallel coordinates and RadVis visualizations using single-and multi-objective optimization

subject: Visualization

subject: Parallel Coordinates Plot

subject: Pareto-front

subject: Single- and multioptimization algorithms

subject: Radial Coordinate Visualization

abstract: Data visualization is crucial to discover hidden patterns and relationships in high dimensional datasets; visualization is an essential branch in data analytics applied in science and engineering fields. This thesis has targeted two state-of-the-art methods from two powerful families of visualization techniques: one with dimension reduction, Radial Coordinate Visualization (RadViz), and the other without dimension reduction, for instance, Parallel Coordinates Plot (PCP). In improving these techniques, evolutionary algorithms have been utilized to determine the optimal ordering of coordinates by considering single- and multi-objectives; using this concept, a smart mutation operator has been proposed and tested comprehensively. In order to investigate the performance of visualization proposed schemes, a benchmark dataset has been proposed, and objective and subjective assessments have been conducted. This investigation shows that the optimal ordering of coordinates can influence crucially visualization results. This thesis’s findings can be utilized to enhance other largescale visualization techniques used in visual-data analytics areas.


title: Examining students’ attitudes toward blended learning in adult literacy and basic skills programs

contributor:
Li, Jia
Kay, Robin

subject:
Blended learning
Success
Individual differences

abstract: Literacy and Basic Skills (LBS) programs offer adult learners, with low literacy and basic skills, opportunities to improve employment skills and pre-requisite courses for entrance into post-secondary education. Barriers to learning that students encounter in LBS programs might be reduced through a blended learning instructional approach. Due to limited access to technology in LBS programs, little is known about attitudes of LBS students toward online learning. The purpose of this study was to investigate the attitudes of community college students at three LBS sites toward blended learning, perceived success in blended learning, and individual differences among students with respect to their attitudes toward blended learning. Over 90% of 149 LBS students (94 male, 55 female) who participated in the study agreed that they achieved success in the program; their learning needs were met through face-to-face class attendance, and they indicated that in-class communication with instructors and peers was important for learning. By comparison, 40% of students agreed that the online activities met their learning needs, and less than 25% of students agreed they could learn online effectively. Some students avoided online content due to their limited computer skills or because they viewed the content as unnecessary for course requirement. Students preferred face-to-face learning over online learning because they viewed the face-to-face format as encouraging, supportive, and collaborative. Students reported that more online learning opportunities were needed when they were not able to attend class or for support of specific learning skills. Age and time out of formal education was significantly and positively correlated with preference for face-to-face learning. Level of education was significantly, negatively correlated with preference for online learning.


title: Effects of combined aerobic and resistance exercise on quality of life and fitness of individuals who are post cancer treatment: A pilot study

contributor:
Lemonde, Manon
Power, Kevin

subject:
Cancer
Exercise
Rehabilitation
Personalized exercise program
Post cancer treatment

abstract:
Cancer Survivors are defined as any individual who has been diagnosed
with cancer and completed treatment, who may or may not be free of the disease
(Speck et al., 2010). Cancer survivors can experience numerous, debilitating and
long lasting side effects. These side effects can occur during and following
cancer treatment and can affect individuals’ daily life. An overview of the
literature on the outcomes that can be experienced from physical activity/exercise
for cancer survivors will be presented.
This study evaluated an 8-week individualized combined aerobic and
resistance training program on individuals post cancer treatment, through
supervised bi-weekly exercise sessions. This study was constructed based on
the review of the benefits of exercise for treatment of cancer and the side effects.
The outcomes of the exercise intervention were evaluated through pre-, post and
three-month follow-up assessments consisting of physical and psychological
testing. Trends of improvements in muscular strength, endurance, reduction in
fatigue levels and perceived Quality of Life (QOL) were identified. These
outcomes further support current literature that, a comprehensive physical fitness
program is important for this population in assisting them with reduction in their
cancer related side effects.


title: Damping acoustic pressure pulsations in pipelines using Helmholtz resonators

subject:
Helmholtz resonator
Acoustic damping
Noise control
Transmission loss
Insertion loss

abstract: In industrial piping systems, centrifugal and reciprocating turbomachinery generate acoustic pressure pulsations, which propagate into the pipeline and interact with piping components, potentially causing vibrations, increased fretting wear, and even fatigue failure. In this thesis, an acoustic damping device known as the Helmholtz resonator (HR) is experimentally studied. The effects of HR cavity volume, pipeline diameter, HR location, the use of multiple HRs, and mean flow velocity are investigated to determine their effects on the acoustic attenuation achieved within a pipeline. Measurements are also performed to clarify the mechanism of attenuation and the effects of incident pressure amplitude on the transmission loss of an HR. The findings of this thesis may be used as practical guidelines for the use of HRs in industrial systems, where characterizing the acoustics is usually difficult and costly, and the available space for damping devices may be limited.

abstract: University of Ontario Institute of Technology


title: Thermal management of the thermochemical Cu-Cl cycle linked with industrial processes for hydrogen production

subject:
Hydrogen production
Thermal management
Energy conversion
Cu-Cl cycle
Heat recovery

abstract: This thesis study develops, analyzes and evaluates three integrated systems using process heats available in industrial applications for hydrogen production via copper-chlorine (Cu-Cl) cycle. The first system consists of single- and multi-stage reheat Rankine cycles, a four-step thermochemical Cu-Cl cycle, and a hydrogen compression system. Systems 2 consists of a thermochemical four-step hydrogen production Cu-Cl cycle, a hydrogen compression system and a multi-stage reheat Rankine cycle. System 3 contains single- and multi-stage reheat Rankine cycles, a thermochemical hydrogen production Cu-Cl cycle, a hydrogen compression system and a reverse osmosis desalination unit. Both Aspen Plus and Engineering Equation Solver software packages are employed for system analysis, modeling and performance assessment. The overall system energy and exergy efficiencies are found to be 39.8% and 40.5% for the first system, 32.7% and 32% for the second system, and 48.6% and 40.2% for the third system.


title: Dynamical effects in crystalline solid state systems: theory of temperature dependent optical response of bulk gaAs and vibrational modification of C(111) 2 x 1 Surface in Comparison to Experiment

subject: Dynamical effects

subject: Thermally perturbed band structure and optical response

subject: Di-electric properties

subject: Gallium arsenide

subject: Semiconductor surfaces

subject: Zero-point vibrations

subject: C(111) 2x1 reconstruction

abstract:
This thesis presents a new theoretical formalism which incorporates dynamical effects in
atomistic electronic structure and related calculations.
This research, fundamental by nature, brings about a deeper understanding of the dynamical
processes in a range of materials. This establishes technologically important correlation
with experimentally measured macroscopic properties and materials characterization. This
method—the first of its kind—is a natural and long overdue extension of customary adiabatically
separated time-independent electronic structure methods. It accounts explicitly for
atomic motion due to thermal and zero-point vibration. The approach developed requires
no direct treatment of time dependence in the quantum mechanical calculations, making
the method widely applicable utilizing currently available electronic structure and ab-initio
molecular dynamics software.
The formalism is extensively applied and demonstrated for the linear optical response
of bulk gallium arsenide and electronic structure of the C(111) 2 x 1 surface. Both cases
are complimented by comparison of key observables to experimental data which may be
used to judge the quality of the results. The results are found to be in good agreement with
experimental data, with most exceptions being readily explainable and well understood.


title: The online identity development of Indo-Caribbean women in Science, Technology, Engineering, and Mathematics (STEM)

contributor:
Hughes, Janette
Petrarca, Diana

subject:
Indo-Caribbean women
STEM identity development
Intersectionality
Antideficit
Equity

abstract: The severe lack of systematically collected race-based data in Canada contributes to the Canadian field of education’s failure to meet the needs of its increasingly diverse demographic of students, resulting in their continued discrimination and oppression. To contribute to the knowledge of the strategies that may be harmful in mitigating these harmful effects, this study conducts an assets-based exploration of the identity development of six Indo-Caribbean women in STEM through the theoretical frameworks of intersectionality and equity, and phenomenological, narrative, and participatory research methodologies. Findings suggest that online communities provide participants numerous educational STEM supports that their institutions failed to provide them. Findings also suggest that the incorporation of racial, cultural, and ethnic identity into STEM education is a protective factor for the participants. Participants provide many recommendations regarding STEM capital development within online communities, many of which are consistent with existing literature.


title: A matrix-free numerical bifurcation method applied to sheared annular electroconvection

subject:
Continuation method
Relative equilibria
Hopf bifurcation
Rayleigh number
Smectic electroconvection

abstract: We investigate the flow transitions in sheared annular electroconvection using matrix-free numerical bifurcation methods. In particular, we study a model that simulates a liquid crystal film in the Smectic A phase suspended between two annular electrodes, and subjected to an electric potential difference and a shear applied by rotating the inner anode at a constant rate. In this thesis, a matrix-free numerical bifurcation method is implemented to identify the transitions of the flow that result due to changes in the main nondimensional control parameter, the Rayleigh number R. This method consists of a natural continuation method by detecting fixed points of two different discrete-time dynamical systems based on numerical integration, and a linear stability analysis that identifies the local behaviour of the flow.


title: Modeling, analysis and optimization of integrated energy systems for multigeneration purposes

subject:
Optimization
Multigeneration system
Efficiency
Exergy

abstract:
Energy use is directly linked to well-being and prosperity across the world. Meeting the growing demand for energy in a safe and environmentally responsible manner is an important challenge. There are around seven billion people on Earth and population growth will likely lead to an increase in energy demand, which depends on the adequacy of energy resources. In addition, increasing population and economic development in many countries have serious implications for the environment, since energy generation processes (e.g., generation of electricity, heating, cooling, and shaft work for transportation and other applications) emit pollutants, many of which are harmful to ecosystems. Utilizing advanced technologies to mitigate global warming and increase the efficiency of energy systems are key objectives, with ways to meet them proposed and tested in many countries. Among these technologies, multigeneration processes stand out as a possibility for making important contributions due to their potential for high efficiencies as well as low operating costs and pollution emissions per energy output.
In this PhD thesis, three novel multigeneration energy systems are considered, analyzed and optimized. The aim is to consider both renewable- and non-renewable-based multigeneration systems. A non-renewable-based multigeneration system is composed of a gas turbine as a prime mover, a double pressure heat recovery steam generator, a single effect absorption chiller, a domestic water heater, an ejector cooling system and PEM electrolyzer. This proposed multigeneration system can produce electricity, heating, cooling, hot water and hydrogen simultaneously. The overall exergy efficiency of the system is 60%, which is 30% higher than the power generation system. Observations show that shifting from a conventional power generation system to a multigeneration cycle leads to a decrease in CO2 emissions of approximately 120 kg/kWh, providing significant motivation to convert to multigeneration cycles. For renewable-based multigeneration systems, biomass-based and integrated ocean thermal energy conversion (OTEC)-based were selected as candidates to meet the requirements of producing electricity, heating, cooling, hot and fresh water and hydrogen.
The biomass-based multigeneration system is composed of a biomass combustor, an ORC cycle for producing electricity, a double-effect absorption chiller for cooling, a heat exchanger for heating, a proton exchange membrane (PEM) electrolyzer for producing hydrogen, a domestic water heater for producing hot water and a reverse osmosis (RO) desalinator for producing fresh water. Pine sawdust is used as the biomass fuel and burned in a biomass
combustor. This multigeneration system increases the exergy efficiency by about 20% and reduces CO2 emissions by about 3500 kg/MWh compared to a conventional power generation system.The last multigeneration energy system examined is an ocean thermal energy conversion (OTEC)-based system integrated with a PV/T solar collector and a single-effect absorption chiller to provide the cooling load of the system. An OTEC system utilizes low-grade energy and has a low energy efficiency. This integrated system uses warm surface seawater to evaporate a working fluid like ammonia or a Freon refrigerant, which drives an ORC turbine to produce electricity, which in turn is used to drive a PEM electrolyzer to produce hydrogen. A reverse osmosis (RO) desalination unit is used to produce fresh water. The exergy efficiency of this integrated system is 37%, which is higher than single generation systems and, in addition, this integrated system has no emissions as it uses ocean energy instead of fuel.
Multigeneration processes can make important contributions due to their potential for high efficiency as well as low operating costs and pollution emissions per energy output. Issues such as fossil fuel depletion and climate change amplify the advantages and significance of efficient multigeneration energy systems.


title: Incorporating daily physical activity in kindergarten children with disabilities: effect on classroom behavior and activity engagement

subject:
Children
Daily physical activity
Disabilities
On-task behavior
Self-stimulatory behavior

abstract: Children with disabilities often experience challenges staying on-task during instructional time in a classroom which is why this an important area of study for teachers and researchers. Physical activity has been shown to have a positive impact on classroom behavior. The purpose of this study was to determine the effectiveness of implementing 4 5-min breaks of daily physical activity (DPA) in a kindergarten classroom of children with disabilities at improving on-task behavior and reducing self-stimulatory behavior (n=14). A secondary purpose was to determine the level of engagement and feasibility of incorporating a DPA program in a classroom of children with disabilities. Classroom Behavior: Results indicated significant increases in on-task behavior from baseline measures to follow-up measures, immediately following 5-minutes of DPA, and from baseline to intervention phase. In addition, self-stimulatory behaviors also significantly reduced in participants who exhibited self-stimulatory behavior. Engagement and Feasibility: Results indicated significant improvements in engagement during DPA from week 1 to week 4. Conclusion: The results of this study indicate that incorporating 4 5-minute bouts of DPA in a classroom of children with disabilities is effective at increasing time on-task and reducing self-stimulatory behaviors. In addition, the DPA program was feasible and engagement level was achieved in students. These findings warrant future research with greater ranges of age groups and a longitudinal study design for children with disabilities.


title: Gendered boomtown impacts: a social service perspective on experiences of women in resource extraction communities

subject:
Gendered boomtown impacts
Women
Oil and gas
Extraction
Masculinities

abstract: The natural resource industry is dynamic, unpredictable, and unconventional. Past research on this industry has examined ‘boomtown impacts’ such has challenges to community cohesion, infrastructure issues, and crime, but few have examined the gendered impacts of the resource industry. Therefore, this thesis examines the gendered impacts associated with resource boomtowns by exploring how the industry impacts women’s lives, what women are impacted, and what resources need to be put in place for women in boomtowns. In exploring gendered impacts, this thesis draws on Connell’s and Messerschmidt’s theorizing on gender, masculinities and emphasized femininity and in-depth interviews with 10 social service workers. The findings indicate that economic dependence, family impacts, and lack of affordable housing are the largest challenges facing women in boomtown communities. This thesis also discusses recommendations offered by social service professionals to improve the lives of women in resource extraction communities and urges future research in this area.