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Scope and Content stated in the place of the abstract. The principal methods of calculating nuclear spin coupling constants by applying perturbation theory to molecular orbital wavefunctions for the electronic structure of molecules are discussed. A new method employing a self-consistent-field perturbation theory (SCFPT) is then presented and compared with the earlier methods. In self-consistent-field (SCF) methods, the interaction of an electron with other electrons in a molecule is accounted for by treating the other electrons as an average distribution of negative charge. However, this charge distribution cannot be calculated until the electron-electron interactions themselves are known. In the SCF method, an initial charge distribution is assumed and then modified in an iterative calculation until the desired degree of self-consistency is attained. In most previous perturbation methods, these electron interactions are not taken into account in a self consistent manner in calculating the perturbed wavefunction even when SCF wavefunctions are used to describe the unperturbed molecule. The main advantage of the new SCFPT approach is that it treats the interactions between electrons with the same degree of self-consistency in the perturbed wavefunction as in the unperturbed wavefunction. The SCFPT method offers additional advantages due to its computational efficiency and the direct manner in which it treats the perturbations. This permits the theory to be developed for the orbital and dipolar contributions to nuclear spin coupling as well as for the more commonly treated contact interaction. In this study, the SCFPT theory is used with the Intermediate Neglect of Differential Overlap (INDO) molecular orbital approximation to calculate a number of coupling constants involving 13c and 19F. The usually neglected orbital and dipolar terms are found to be very important in FF and CF coupling. They can play a decisive role in explaining the experimental trend of JCF among a series of compounds. The orbital interaction is found to play a significant role in certain CC couplings. Generally good agreement is obtained between theory and experiment except for JCF and JFF in oxalyl fluoride and the incorrect signs obtained for cis JFF in fluorinated ethylenes. The nature of the theory permits the latter discrepancy to be rationalized in terms of computational details. The value of JFF in difluoracetjc acid is predicted to be -235 Hz. The SCFPT method is used with a theory of dπ - pπ bonding to predict in agreement with experiment that JCH in acetylene will decrease when that molecule is bound in a transition metal complex. Thesis Doctor of Philosophy (PhD)

Soil vapour extraction (SVE) is a widely accepted and cost-effective technique used to remediate unsaturated soils contaminated with volatile organic compounds (VOCs). In order to improve SVE design, it is necessary to develop a comprehensive mathematical model that incorporates multiphase flow and multicomponent transport with nonequilibrium mass transfer. The model must include key controlling parameters such as relative permeability, dispersion coefficients, phase densities and interphase mass transfer. Research has been completed on comprehensive three-dimensional SVE models entitled 3D-SVE-L/F. Use of these models allows quantitative evaluation of the SVE tailing effect, a current obstacle for SVE technology. The numerical solutions of the 3D-SVE-L/F models are obtained using FEMLAB, a commercial multi-physics modeling software developed by COMSOL Inc.; 3D-SVE-L/F have been calibrated against known data from lab-scale and field-scale SVE operations. The numerical simulation study indicates that 3D-SVE-L/F models can simulate SVE tailing effects. Accordingly, the pressure field and the distribution of the concentration of contaminant in the soil gas phase as well as the saturation reasonably are predicted. The completed multivariable sensitivity analysis of the calibrated 3D-SVE-L/F models under a 95% confidence interval manifests that empirical mass transfer parameters consisting of the NAPL to vapour mass transfer coefficient are the most sensitive, followed by air-phase permeability. Dispersivity is the least sensitive. Comparison of the mass transfer coefficients between lab and field has shown that the field conditions are more resistant to mass transfer, consistent with high water content, more complex soil properties, and site heterogeneity. A challenge facing SVE designs is estimating the length of SVE treatment time using a 3D-SVE model; a concept referring to a critical time index (CTI) was developed to predict the closure time for stopping an SVE operation. Applying CTI to an SVE operation may save operational time and cost. Additionally, the 3D model developed in this study can be used to assist in field-scale SVE design.

Improving the understanding of the way neurons interact at the whole-brain level is of great interest to neuroscientists. These “circuit diagrams” of the human brain could revolutionize the way neurological diseases are treated, but before this level of study can be conducted, neuroimaging technology must be improved. Using the model organism Drosophila melanogaster, improvements in spatiotemporal resolution of microscopy techniques are being made. Microfluidic devices have been created to improve the spatial resolution of live neuroimaging in Drosophila 3rd instar larva using confocal microscopy, but the desired high temporal resolution has not yet been demonstrated in a live organism. In this research, the high spatial resolution possible using an immobilization device for live larvae is combined with the high temporal resolution of the light-sheet microscope. A microfluidic device was designed to be compatible with the physical constraints of the light-sheet microscope while simultaneously incorporating a 3D-segmental pinning immobilization channel to ensure minimized motion of the CNS of the larvae. The device achieved single-cell resolution (< 5 μm) of the whole brain of a live, intact larva. Z-stack images and time-series captures demonstrated the capability of the microscope to record volumetric images and high image acquisition rates of the live, intact larval CNS respectively. Thesis Master of Applied Science (MASc)

Prolonging the battery lifetime of sensors has been one of the most important issues in wireless sensor networks (WSNs). With the development of Wireless Power Transfer (WPT) technology, sensors can be recharged and possibly have infinite lifetime. One common approach to achieving this is having a wireless charging vehicle (WCV) move in the system coverage area and charge sensors nearby when it stops. The duration that the WCV stays at each charging location, the amount of traffic that each sensor carries, and the transmission power of individual sensors are closely related, and their joint optimization affects not only the data transmissions in the WSN but also energy consumption of the system. This problem is formulated as a mixed integer and nonconvex optimization problem. Different from existing work that either solves similar problems using genetic algorithms or considers charging sensors based on clusters, we consider the optimum charging time for each sensor, and solve the joint communication and charging problem optimally. Numerical results demonstrate that our solution can significantly reduce the average power consumption of the system, compared to the cluster-based charging solution. Thesis Master of Applied Science (MASc) In a wireless sensor network (WSN), sensor nodes monitor the physical environment and forward the collected data to a data sink for further processing. Sensors are battery powered and, therefore, prolonging the lifetime of their batteries is critically important. In a rechargeable WSN (RWSN), prolonging the battery lifetime of sensors is achieved through reducing communication energy and recharging the batteries periodically. Reducing the communication energy consumption is done through choosing the best forwarding sensors (i.e., routing) for data collected by each sensor and deciding the transmission power of each sensor (i.e., power allocation). Recharging the batteries is achieved through harvesting energy from external sources. In this thesis, we consider a RWSN that uses wireless power transfer as the energy harvesting technology and jointly optimizes charging and communications in order to minimize the power consumption of the RWSN.

As artificial intelligence (AI) increasingly revolutionizes healthcare, the development of AI-powered medical tools holds promise for improving patient care by increasing the accuracy of diagnoses, providing precise treatments, and more. Despite the promise of AI tools, they suffer from a critical limitation due to a lack of representation of elderly experiences. In this paper, I examine the multilayered issue of the underrepresentation of the elderly in the data used in the development of medical AI tools, assessing its implications and proposing relevant solutions. This thesis is divided into five chapters, with Chapter One providing an overview of the current state of AI, highlighting the potential of AI-powered tools for improving healthcare outcomes, and their relevant limitations. Chapters Two to Four assess how various sources of AI training data (i.e., clinical trials, electronic health records [EHRs] and self-reporting tools) fail to adequately represent elderly experiences. Clinical trials have long suffered from a lack of elderly representation, originating from efforts to protect vulnerable populations from research-induced harm. While the attempt has been to protect, the result has been to arbitrarily exclude older adults from participation in clinical research. As such, there is a lack of diverse data that accurately reflects the complexities of their unique medical needs. Further, the presence of age-based bias towards the elderly presents an additional layer of concern. The manifestation of such biases in EHRs perpetuates inaccurate data that informs the development of medical AI tools, consequently maintaining disparities in healthcare. Additionally, self-reporting tools fail to account for the distinct cognitive and physical abilities of older adults, presenting useability challenges that result in the inadequate representation of elderly experiences in the data. Finally, the paper culminates with a compilation of proposed solutions to address the underrepresentation of elderly experiences in medical AI development. These solutions propose efforts to improve elderly participation in clinical trials, efforts to mitigate physician bias in EHRs, and the design of self-reporting tools that are cognizant of the unique needs of older adults. Thesis Master of Arts (MA)

This project cumulates into a policy brief which provides recommendations for changes to the policy involving psychoeducational assessment for students with learning disabilities enrolled in Adult Basic Upgrading (ABE). As much as 25% of students enrolled in ABE programs have a documented disability and many more are suspected. This project provides a review of the literature outlining the implications of education on societal and individual functioning as well as its significance in supporting inclusion and social justice practices. The writer was further informed through examining government documentation and websites, e-mail communication with two international initiations, an interview with a former department head of a disability service center, meetings with members of the provincial articulation subcommittee and attendance at meetings involving educators and support staff of ABE students. This project is intended to promote awareness of the inequality created by current policies around academic accommodations for students with learning disabilities and provide justification for policy reform. https://viurrspace.ca/bitstream/handle/10613/7189/Browing.pdf?sequence=3&isAllowed=y

This thesis investigates the characteristics of a long aspect ratio synthetic jet actuator and its application for the active control of the vibrations of the downstream cylinder in a tandem cylinder arrangement. A long aspect ratio synthetic jet is produced through an axial slit along part of the length of a cylinder. The jet is excited acoustically by a pair of loudspeakers mounted at the cylinder terminations. The study compares between the performance of two different slits with aspect ratios of 273 and 773. The comparison is based on the spanwise distribution of the mean jet velocity and phase between the jet velocity fluctuations and the excitation signal. Three different frequencies and amplitudes are used to excite the speakers covering the range of frequencies used in the control application. For both cases studied the mean centerline velocity of the jet increases with increasing the amplitude of the exciting signal, but decreases with increasing its frequency. Moreover, velocity deficits of up to 30% are evident as the midspan of the cylinder is approached from either end. Similar trends are also observed for the centerline phase distributions of the velocity fluctuations, with deficits of up to 130°. However, it is observed that for the long slit case the deficits in both the velocity and phase distributions are much larger than those for the short one. The synthetic jet is then mounted in the upstream cylinder of a tandem cylinder arrangement to be used as a control actuator for controlling the vibrations of the downstream cylinder. A simple feedback control mechanism is used at a Reynolds number of about 6.3x104. This Reynolds number corresponds to the case where the iii downstream cylinder’s response is dominated with two frequency components, one at the resonance frequency of the cylinder, which is excited by broadband turbulence in the flow, and the other at the vortex shedding frequency. Both slits studied for the characterization experiments are used to compare their performance as control actuators. Both jets produce comparable reductions in the vibration of the downstream cylinder. A reduction of about 20% in the total RMS amplitude of the vibrations signal is achieved. This amounts to a reduction of about 50% in the resonant peak and an average value of about 40% in the vortex shedding peak. The optimal values of gain and time lag of the controller are then used to investigate the effect of the jet on the flow. It is found that the short slit jet produced an effect that was traced up to 1.875 diameters downstream, while the effect of the long slit jet dropped dramatically very close to the upstream cylinder. Master of Applied Science (MASc)

Biochar is a carbon-rich material that could be produced through pyrolysis of agricultural residues such as rice straw and rice husk. Biochar has been proven to be an efficient adsorbent used in wastewater treatment. As the most common way to dispose of agricultural residues is on-field open burning, biochar production was considered as a possible method of agricultural residue valorization. To investigate the impacts of biochar production and its potential in agricultural residue disposal, a life cycle assessment was performed to quantify the impacts of four types of rice straw and rice husk biochar in this study. By comparing the impacts between rice straw open burning and biochar production, environmental benefits were found in global warming, acidification, smog formation and particulate matter formation. This reveals the feasibility of rice residue-based biochar production as opposed to open burning. The impacts of biochar application in wastewater treatment system were also investigated by implementing life cycle assessment. The results showed that substantial mitigations could be achieved by treating wastewater using biochar. IC-IMPACT