Vehicular ad hoc networks have emerged as a promising area of research in academic fields. However, it presents a challenge to design a realistic coverage protocol for ve- hicular networks, due to the service requirements, assorted mobility patterns, resource constraints and irregularity of the service area. It is also a challenge to meet a high quality of coverage with a tight deployment budget. In order to resolve these problems, this thesis proposes a resource-constrained coverage protocol with statistical analysis, which aims to consider the application demands, mobility patterns of vehicles, resource limitations, and geometrical attributes of road networks. We study two types of resource-constrained coverage: the continuous coverage model and the sparse coverage model. We then reduce each model to a Knapsack Constrained Steiner Tree problem and a Maximum Coverage Problem, respectively. Since the two reduced problems are NP-hard, we resolve each of them with the Lagrangian Decompo- sition approach and greedy algorithm. By taking the dimensions of road segments into account, our coverage protocol provides a buffering operation scheme to suit different types of road topology. By discovering hotspots from the historical trace files, the pro- posed protocol is able to depict the mobility patterns and to discover the most valuable regions of a road system. To solve the problems of resource constraint, we provide two variants of continuous coverage and sparse coverage by taking budget constraint and quality constraint into consideration. The comparison with other mature algorithms verifies that our coverage protocol is reliable, and suitable for urban vehicular networks.

This thesis introduces an efficient and robust approach for 3D reconstruction of complete head models with consistent parameterization and personalized shapes from several possible inputs. The system input consists of Cyberware laser-scanned data where we perform scanning task as well as publically available face data where (i) facial expression may or may not exist and (ii) only partial information of head may exist, for instance only front face part without back part of the head. Our method starts with a surface reconstruction approach to either transfer point clouds to a mesh structure or to fill missing points on a triangular mesh. Then, it is followed by a registration process which unifies the representation of all meshes. Afterward, a photo-cloning method is used to extract an adequate set of features in a semi-automatic way on snapshots taken from front and left views of provided range data. We modify Radial Basis Functions (RBFs) deformation so that it would be based on not only distance, but also regional information. Using feature point sets and modified RBFs deformation, a generic mesh can be manipulated in a way that closed eyes and mouth movements like separating upper lip and lower lip can be properly handled. In other word, such mesh modification method makes construction of various facial expressions possible. Moreover, new functions are added where a generic model can be manipulated based on feature point sets to consequently recover missing parts such as ears, back of the head and neck in the input face. After feature-based deformation using modified radial basis functions, a fine mesh modification method based on model points follows to extract the fine details from the available range data. Then, some post refinement procedures employing RBFs deformation and averaging neighboring points are carried out to make the surface of reconstructed 3D head smoother and uniform. Due to existence of flaws and defects on the mesh surface such as flipped triangles, self-intersections or degenerate faces, an automatic repairing approach is leveraged to clean up the entire surface of the mesh. The experiments which are performed on various models show that our method is robust and efficient in terms of accurate full head reconstruction from input data and execution time, respectively. In our method, it is also aimed to use minimum user interaction as much as possible.

Road network of a region is of a paramount importance in the overall development. Management of road traffic is a key factor for the city authority and reducing the road traffic congestion is a significant challenge in this perspective. In this thesis, a Wireless Sensor Network (WSN) based road-traffic monitoring scheme with dynamic mathematical traffic model is presented that will not necessarily include all adjacent intersections of a block; rather the important major intersections of a city. The objective of this scheme is to reduce the congestion by re-routing the vehicles to better performing road-segments by informing the down-stream drivers through broadcasting the congestion information in a dedicated radio channel. The dynamic model can provide with the instantaneous status of the traffic of the road-network. The scheme is a WSN based multi-hop relay network with hierarchical architecture and composed of ordinary nodes, Cluster-Head nodes, Base Stations, Gateway nodes and Monitoring and Control Centers (MCC) etc. Through collecting the traffic information, MCC will check the congestion status and in defining the congestion, threshold factors have been used in this model. For the congested situation of a road-segment, a cost function has been defined as a performance indicator and estimated using the weight factors (importance) of these selected intersections. This thesis considered a traffic network with twelve major intersections of a city with four major directions. Traffic arrivals in these intersections are assumed to follow Poisson distribution. Model was simulated in Matlab with traffic generated through Poisson Random Number Generator and cost function was estimated for the congestion status of the road-segments over a simulation period of 1440 minutes starting from midnight. For optimization purpose we adopted two different approaches; in the first approach, performance of the scheme was evaluated for all threshold factor values iteratively one at a time, applying a threshold factor value to define threshold capacities of all the road segments; traffic was generated and relative cost has been estimated following the model specifications with the purpose of congestion avoidance. In the second approach, different values of threshold factor have been used for different road segments for determining the optimum set-up, and exhaustive search technique has been applied with a smaller configuration in order to keep computations reachable. Simulation results show the capacity of this scheme to improve the traffic performance by reducing the congestion level with low congestion costs.

This dissertation explored the way in which bumblebees' visual system helps them discover their first flower. Previous studies found bees have unlearned preferences for parts of a flower, such as its colour and shape. The first study pitted two variables against each other: pattern type: sunburst or bull's eye, versus the location of the pattern: shapes appeared peripherally or centrally. We observed free-flying bees in a flight cage using Radio-Frequency Identification (RFID) tracking. The results show two distinct behavioural preferences: Pattern type predicts landing: bees prefer radial over concentric patterns, regardless of whether the radial pattern is on the perimeter or near the centre of the flower. Pattern location predicts exploration: bees were more likely to explore the inside of artificial flowers if the shapes were displayed near the centre of the flower, regardless of whether the pattern was radial or concentric. As part of the second component, we implemented a mathematical model aimed at explaining how bees come to prefer radial patterns, leafy backgrounds and symmetry. The model was based on unsupervised neural networks used to describe cognitive mechanisms. The results captured with the results of multiple behavioural experiments. The model suggests that bees choose computationally "cheaper" stimuli, those that contain less information. The third study tested the computational load hypothesis generated by the artificial neural networks. Visual properties of symmetry, and spatial frequency were tested. Studying free-flying bees in a flight cage using motion-sensitive video recordings, we found that bees preferred 4-axis symmetrical patterns in both low and high frequency displays.

The geochemistry of surface media above two known U deposits were examined to observe any possible dispersion products could be detected from them, and based on these findings, improved geochemical exploration techniques are proposed to reduce cost of finding undiscovered U resources. This study examined the materials overlying the Phoenix deposits, which have indicated resources of approximately 58.2 million lbs U3O8 grading 15 wt% that lie at 400 m depth below surface at the unconformity between the overlying Athabasca sandstones and Paleoproterozoic basement rocks. Aqua regia digestion, ammonium acetate at pH 5 and hydroxylamine leaches revealed U, Pb, Co, Ni, Mo, and W anomalies in humus and U, W and As anomalies in B-horizon soils above the ore zones and the basement location of a deposit-hosting, northeast-trending “WS Hanging Wall” shear zone over a three year period. These metal signatures suggest likely upward transport of metals from the deposits to overlying sandstones, and subsequently into the overlying till and soils. This study also looked at materials above the Millennium U deposit, which has indicated resources of 68.2 million lbs U3O8 grading 4 wt% at ~750 m depth that occurs along a major fault in granites & metamorphosed pelites of Paleoproterozoic age below the Athabasca sandstones. Soil samples taken over the surface projections of an ore-hosting fault and the ore zone yielded anomalous values in U, Ni, Cu and Pb in aqua regia digestion of humus and U, Cu and Pb values in ammonium acetate leach of pH 5 of B-horizon soils. Hydroxylamine leach did not yield as many anomalies as ammonium acetate leach. Measured 4He/36Ar ratios of gas dissolved in water-filled drill holes were observed to be up to about 700 times the atmosphere value for air-saturated water, revealing the presence of radiogenic 4He that was likely produced from decaying U and released in the groundwater above the deposit. Our results suggest upward migration of metals to surface through porous sandstone and fault systems at Phoenix, and upward migration of metals along faults and He gas at Millennium. Both studies indicate the importance of the traverse method of sampling over targets perpendicular to the last major ice-flow event to discern U deposits that are defined by other means.

Use of waste glycerol as fuel in microbial fuel cells (MFCs) would result in the production of valuable metabolites and electricity, to the benefit of biodiesel operations. In this research, the effect of salt and other compounds found in waste glycerol from biodiesel production on the metabolism and performance of three cultures (Escherichia coli W3110, Propionibacterium freudenreichii ssp. shermanii and mixed culture AR2), used as anodic catalysts in an MFC was studied. MFC experiments were performed in parallel with serum bottle fermentations to allow for comparison of glycerol consumption and metabolite yield. The effect of salt content on the performance of all three cultures was positive in most cases and negligible in others. Using waste glycerol with an increased concentration of other compounds (other than salt) only reduced the performance of AR2, however an inhibitory effect on the rate of glycerol consumption was observed with both AR2 and P. freudenreichii ssp. shermanii. For all strains, the rate of glycerol consumption was slower in MFCs than in fermentations as a result of the electrochemical environment; the yield of various metabolites also differed.

Background: Subjective Memory Concerns (SMC) in seniors can be one of the earliest indicators of future dementia. There is a lack of research into the nature of these concerns and functional impairments. Methods: This retrospective secondary analysis gathered data from 67 healthy seniors aged 65+ using neuropsychological tests, memory concern questionnaires and daily functioning scales. Informants corroborated memory concerns and daily functioning. Participants comprised two groups: SMC if worried about their memory and Not Concerned about Memory if not. Results: People with SMC report more difficulty with word finding, remembering appointments, learning to use new equipment, and remembering details of social and personal events. Informants perceive word finding difficulties and minor problems with vocational abilities and bowel/bladder control in SMC participants. Conclusions: The SMC group primarily reports social difficulties. Further research is required to create a comprehensive list of cognitive concerns, which will ultimately improve care of the SMC population. Contexte: Les préoccupations subjectives de mémoire (PSM) chez les aînés peuvent être indicatives d’une démence future, bien qu’il existe un manque d’information sur les préoccupations et l’effet fonctionnel. Méthodes: Une analyse rétrospective secondaire de questionnaires de mémoire, de tests neuropsychologiques, et d’échelles fonctionnelles a été entreprise auprès de 67 personnes, en bonne santé, âgées de 65 ans et plus. Les aidants naturels ont pu appuyer les préoccupations cognitives et le niveau de fonctionnement chez deux groupes de participants: ceux avec préoccupations ou non. Résultats: Les participants PSM relèvent des difficultés de manque du mot, de rappel (rendez-vous, événements sociaux), et d’utilisation de nouveaux équipements. Les aidants naturels ont aussi trouvé de légères difficultés au travail et au niveau du contrôle intestinal et urinaire. Conclusions: Les PSM identifient principalement des lacunes au niveau social. Les recherches devront viser l’identification d’une liste exhaustive des préoccupations afin de pouvoir octroyer de meilleurs soins.

Femoroacetabular impingement (FAI) is a hip joint deformity that causes joint pain, decreases joint range of motion and results in abnormal kinematic and kinetic characteristics. It is not known whether these biomechanical variations are caused by the actual mechanical impingement aspect of hip deformity or neuromuscular adaptations and soft tissue damage associated with pain. The purpose of this study was to investigate the effects of femoroacetabular cam deformity (FAD) during daily functional tasks. This was accomplished by measuring and comparing the hip joint biomechanics of symptomatic FAI (sFAI), asymptomatic FAD, and control (CON) subjects. Fifty one subjects volunteered to the study (n = 51; CON = 17, FAD = 18, sFAI = 16) and they performed 6 simulated activities of daily living: stair ascent and descent, sit-to-stand and stand-to-sit, dynamic range of motion, maximum depth squats and level walking tasks while motion ground reaction force and muscle activity were recorded. However, only the squat and level walking tasks were analyzed for this thesis. For each task, three-dimensional kinematics and kinetics were recorded and analyzed. Qualitative questionnaires (HOOS and WOMAC) and physical exams were also part of the testing protocol, and maximum voluntary isometric contractions (MVIC) were collected as part of a separate EMG protocol. The EMG results were not analyzed but the MVIC results were and the moments of force were determined. The sFAI group had significantly reduced scores for all HOOS and WOMAC metrics compared to FAD and CON. The sFAI group had significantly reduced external rotation, internal rotation, and a trend indicating reduced hip flexion compared to FAD and CON groups. The FAD group had a trend indicating reduced internal rotation compared to CON. There were no differences in the moments of force between groups for the MVICs. No statistically significant differences were observed between groups for the squat trials, however, the sFAI group showed biomechanical variations. Both the CON and FAD groups were able to squat deeper, had greater pelvic range of motion and a larger maximum hip and knee flexion angle compared to sFAI. Similarly, the walking tasks did not elucidate any between group differences in biomechanical characteristics. Yet, there was a noticeable trend of decreased peak hip abduction angle in the sFAI group compared to CON. This result may be indicative of a gait adaptation based on the pain that sFAI subjects endure over a long period of time. Interestingly, the FAD group did not have obvious gait patterns similar to either the CON or sFAI, making it unclear if the asymptomatic cam deformity has any gait adaptation effects. Since no differences were observed between FAD and CON in squatting and walking, the actual bone deformity may not be the cause of restricted motion during daily activities as previously thought. Internal rotation physical examination appears to indicate potential restrictions in the FAD compared to CON, and may be the best parameter to assess differences between groups and predict the presence of cam deformity. It is suggested that the presence of pain, caused by soft tissue damage over time, may be confounding factors leading to the biomechanical and neuromuscular discrepancies observed in sFAI, and should be the next avenue of study.

Intensive care units (ICUs) emerged across Canada during the early 1960s, significantly contributing to the image of Western hospitals as places of scientific advancement that predominated over much of the twentieth century. ICUs rapidly became both a resource intensive and expensive type of care as the number and size of units increased to accommodate diverse patient populations and treatment options. Nurses enabled the formation and growth of ICUs through their constant presence and skilled care. There has been limited research, however, regarding the historical development of Canadian ICUs, the relationships between nurses and other personnel in such units, how they developed an identity as ICU nurses, or how ICU nursing became a specialty practice. Situated within the broader histories of hospitals, healthcare, and nursing, this study uses a social history approach to examine nurses’ experiences within Canadian ICUs between 1960 and 2002. Berger and Luckmann’s Social Construction of Reality provided a lens for analysis and interpretation of oral histories, photographs, professional literature of the time period under study, and both archival and organizational records. This thesis argues that ICU nurses’ relationships with one another, in the context of a technologically complex environment, socially constructed their knowledge and skill acquisition, their socialization as ICU nurses, and the development of a specialized body of knowledge that ultimately led to formal recognition of ICU nursing as a specialty in Canada.

This thesis analyzes the problem of acquiring stereoscopic images in all gazing directions around a reference viewpoint in space with the purpose of creating stereoscopic panoramas of non-static scenes. The generation of immersive stereoscopic imagery suitable to stimulate human stereopsis requires images from two distinct viewpoints with horizontal parallax in all gazing directions, or to be able to simulate this situation in the generated imagery. The available techniques to produce omnistereoscopic imagery for human viewing are not suitable to capture dynamic scenes stereoscopically. This is a not trivial problem when considering acquiring the entire scene at once while avoiding self-occlusion between multiple cameras. In this thesis, the term omnidirectional refers to all possible gazing directions in azimuth and a limited set of directions in elevation. The acquisition of dynamic scenes restricts the problem to those techniques suitable for collecting in one simultaneous exposure all the necessary visual information to recreate stereoscopic imagery in arbitrary gazing directions. The analysis of the problem starts by defining an omnistereoscopic viewing model for the physical magnitude to be measured by a panoramic image sensor intended to produce stereoscopic imagery for human viewing. Based on this model, a novel acquisition model is proposed, which is suitable to describe the omnistereoscopic techniques based on horizontal stereo. From this acquisition model, an acquisition method based on multiple cameras combined with the rendering by mosaicking of partially overlapped stereoscopic images is identified as a good candidate to produce omnistereoscopic imagery of dynamic scenes. Experimental acquisition and rendering tests were performed for different multiple-camera configurations. Furthermore, a mosaicking criterion between partially overlapped stereoscopic images based on the continuity of the perceived depth and the prediction of the location and magnitude of unwanted vertical disparities in the final stereoscopic panorama are two main contributions of this thesis. In addition, two novel omnistereoscopic acquisition and rendering techniques were introduced. The main contributions to this field are to propose a general model for the acquisition of omnistereoscopic imagery, to devise novel methods to produce omnistereoscopic imagery, and more importantly, to contribute to the awareness of the problem of acquiring dynamic scenes within the scope of omnistereoscopic research.