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Numerous aspects of job scheduling in manufacturing systems have been the focus of several studies in the past decades. However, human factors in manufacturing systems such as workers’ mental conditions are still neglected issues and have not received adequate attentions. Job boredom and mental fatigue are both aspects of workers’ mental condition. They affect work performances by increasing sick leave duration and decreasing work productivity. On the other hand, job rotation could be an alternative strategy to cope with such human issues at work. The benefits of job rotation for both employees and firms have been widely recognized in the literature. Although some studies found job rotation as a means to reduce workers' physical work-related traumas, they did not consider the effect of variable mental conditions on workers. Despite the proven importance of boredom and mental fatigue at the workplace, they have not been a combined precise objective of any job rotation problem in current literature. The study of mental conditions proposed in this paper attempts to extend the previous works by addressing new methods and developing a feasible solution to increase manufacturing productivity. A new job scheduling program has been designed specifically which combines a new job rotation model and a job assignment method.

En milieu stratifié-tournant, les ondes supportées par un tourbillon colonnaire vertical peuvent être instables en raison d'un rayonnement d'ondes, un phénomène connu sous le nom d'instabilité radiative. Dans la première partie de cette thèse, on étudie numériquement et analytiquement l'effet d'une rotation planétaire sur cette instabilité. En présence de rotation cyclonique, le rayonnement d'ondes diminue et le taux de croissance maximum de l'instabilité radiative décroît exponentiellement quand la rotation augmente. Il devient negligeable quand le nombre Rossby est inférieur à l'unité. En présence de rotation anticyclonique avec un nombre de Rossby supérieur à -1, l'instabilité centrifuge est stable mais on montre que l'instabilité radiative se produit également si le nombre d'onde azimutal est plus grand que 2 et le profil de vorticité est suffisamment raide. Le taux de croissance dans ce régime fortement anticyclonique est comparable à celui dans le régime cyclonique. La principale conclusion est donc qu'un tourbillon colonnaire en milieu stratifié-tournant peut être instable pour n'importe quel nombre de Rossby. Le mécanisme et les propriétés de l'instabilité radiative sont expliqués par une analyse WKBJ pour grands nombres d'ondes. Dans la deuxième partie de cette thèse, la stabilité de l'écoulement de Taylor-Couette stratifié est analysée quand la vitesse angulaire augmente radialement, une régime encore jamais exploré. On montre que cet écoulement est instable vis à vis d'une instabilité stratorotationelle. Cette instabilité est similaire à l'instabilité radiative d'un tourbillon en régime fortement anticyclonique. Ces résultats révèlent que l'écoulement de Taylor-Couette stratifié est toujours instable sauf dans la limite d'une rotation solide.

Dans cette thèse, nous proposons une approche méthodologique et algorithmique pour la reconnaissance visuelle d'intentions, basée sur la rotation et le mouvement vertical de la tête et de la main. Le contexte dans lequel cette solution s'inscrit est celui d'une personne handicapée, dont la mobilité est assurée par un fauteuil roulant. Le système proposé constitue une alternative intéressante aux interfaces classiques de type manette, boutons pneumatiques, etc. La séquence vidéo, composée de 10 images, est traitée en utilisant différentes méthodes pour construire ce qui dans cette thèse est désigné par " courbe d'intention ". Une base de règles est également proposée pour classifier chaque courbe d'intention. Pour la reconnaissance basée sur les mouvements de la tête, une approche utilisant la symétrie du visage est proposée pour estimer la direction désirée à partir de la rotation de la tête. Une Analyse en Composantes Principales (ACP) est utilisée pour détecter l'intention de varier la vitesse de déplacement du fauteuil roulant, à partir du mouvement vertical de la tête. Pour la reconnaissance de la direction basée sur la rotation de la main, une approche utilisant à la fois la symétrie verticale de la main et un algorithme d'apprentissage (réseaux neuronaux, machines à vecteurs supports ou k-means), permet d'obtenir les courbes d'intentions exploitées par la suite pour la détection de la direction désirée. Une autre approche, s'appuyant sur l'appariement de gabarits de la région contenant les doigts, est également proposée. Pour la reconnaissance de la vitesse variable basée sur le mouvement vertical de la main, deux approches sont proposées. La première utilise également l'appariement de gabarits de la région contenant les doigts, et la deuxième se base sur un masque en forme d'ellipse, pour déterminer la position verticale de la main. Les résultats obtenus montrent de bonnes performances en termes de classification aussi bien des positions individuelles dans chaque image, que des courbes d'intentions. L'approche de reconnaissance visuelle d'intentions proposée produit dans la très grande majorité des cas un meilleur taux de reconnaissance que la plupart des méthodes proposées dans la littérature. Par ailleurs, cette étude montre également que la tête et la main en rotation et en mouvement vertical constituent des indicateurs d'intention appropriés

Numerous aspects of job scheduling in manufacturing systems have been the focus of several studies in the past decades. However, human factors in manufacturing systems such as workers’ mental conditions are still neglected issues and have not received adequate attentions. Job boredom and mental fatigue are both aspects of workers’ mental condition. They affect work performances by increasing sick leave duration and decreasing work productivity. On the other hand, job rotation could be an alternative strategy to cope with such human issues at work. The benefits of job rotation for both employees and firms have been widely recognized in the literature. Although some studies found job rotation as a means to reduce workers' physical work-related traumas, they did not consider the effect of variable mental conditions on workers. Despite the proven importance of boredom and mental fatigue at the workplace, they have not been a combined precise objective of any job rotation problem in current literature. The study of mental conditions proposed in this paper attempts to extend the previous works by addressing new methods and developing a feasible solution to increase manufacturing productivity. A new job scheduling program has been designed specifically which combines a new job rotation model and a job assignment method.

Willow (Salix spp.), a major source of biomass and renewable fiber production, is one of the best choices for short-rotation intensive culture (SRIC) in Canada. Since fungal communities play important roles in the plant’s health status, it is vital to understand their interactions with willows and their roles in the sustainability of SRIC. In this study, fungal diversity of the above-ground organs (stem/leaf) of healthy and diseased willow plants in western Canadian Prairies were assessed using cultural and PCR-denaturing gradient gel electrophoresis (DGGE) techniques. Comparison of the mycoprofiles within established plantations vs. newly introduced cuttings revealed differences in the fungal communities. Ascomycota were mainly isolated, followed by Basidiomicota and Zygomycota. Willow genotypes seem have an influence on the abundance of fungal pathogens and disease severity; among them Charlie (Salix alba x gladfelteri) and SV1 (S. eriocephala) cultivars demonstrated superior performances. Photosynthesis measurements and biomass compositions confirmed these findings. Potentially pathogenic fungi (Dothioraceae, Diaporthaceae, Glomeraceae, and Pleosporaceae) dominated in diseased or symptomatic willows, whereas potentially beneficial fungi (Coniochaetaceae, Hypoceraceae, Nectriaceae, Trichocomaceae, and Agaricaceae) prevailed in healthy plants. In-vivo and greenhouse assays showed that inoculation with potentially pathogenic fungi induced leaf necrosis, anthracnose and open cankers. However, suppression of the latter was still possible using fungal antagonists. Hence, assessment of stem/bark and leaf fungal communities with respect to willow genotypes, cuttings origin, and SRIC location, is useful for the design of an effective management strategy to increase the productivity of the SRIC-biomass systems.

We present a geometrical and mathematical solution to a problem faced in the glass industry in this work. Volume measurement of the glass gob is vital in making glassware. Geometric models were used to represent the glass gob. A line scan camera system takes the images of the glass gob and the volume information of the glass gob is obtained by the image processing in the industry. This work is carried out to implement a simulator which estimates the change in the volume measurement of glass gob through line scan when it is rotated or when its shape is changed. A mixture of graphical and mathematical approaches is used to carry out this study. Geometric models have been used to represent the different gob models. Geometric models facilitate the manipulation of volumetric data.A simple and effective technique is used in this work. The problem is divided into steps. Volume measurement through a line scan technique is simulated. An easy to use graphical user interface (GUI) is designed to interact with the gob model and check the results of volume measurements.We present a geometrical and mathematical solution to a problem faced in the glass industry in this work. Volume measurement of the glass gob is vital in making glassware. Geometric models were used to represent the glass gob.A line scan camera system takes the images of the glass gob and the volume information of the glass gob is obtained by the image processing in the industry.This work is carried out to implement a simulator which estimates the change in the volume measurement of glass gob through line scan when it is rotated or when its shape is changed. A mixture of graphical and mathematical approaches is used to carry out this study. Geometric models have been used to represent the different gob models. Geometric models facilitate the manipulation of volumetric data. A simple and effective technique is used in this work. The problem is divided into steps. Volume measurement through a line scan technique is simulated. An easy to use graphical user interface (GUI) is designed to interact with the gob model and check the results of volume measurements.

Several farming systems, in a region of the Dark Brown soil zone west of Saskatoon, were investigated to identify farming practices that are soil-conserving, or soil-degrading, by measuring their effects on soil quality. The study identified soil properties that are practical and measurable indicators of soil quality, and factors that influence farmers adoption of soil-conserving farming practices. On coarse-loamy to sandy-textured, glaciolacustrine soils, farming systems with long rotations and adequate fertilizer inputs or permanent cover, were associated with a higher quality of soils than tillage-intensive crop-fallow systems. Better soil quality was attributed to the larger addition of crop residues, enabling long-rotation soils to maintain a relatively large pool of mineralizable C, N, and P, and a large microbial biomass. The larger microbial biomass was an indicator of the improved quality of continuously cropped soils as a habitat for microorganisms, and their increased ability to cycle nutrients and C. Other indicators of improved soil quality were increased soil thickness, organic C content, infiltration rate, and aggregation, and decreased bulk density and salinity. Slightly lower A horizon pH was the only negative indicator of quality associated with the continuously cropped soils. The ability of farmers to adapt the longer-rotation systems was constrained by capital and labour limitations, management skills or lifestyle choices. Farmers with limited capital were less willing to invest in the inputs required to continuously crop, because they perceived an increase in the risk of crop failure in that system. Farmers with a large land base, or with off-farm employment, may not have the time or labour to seed and harvest all of their land every year. Among the study farms, the farmers who were best able to adopt continuous cropping systems were those involved in multifamily, mixed farms. There were less labour and capital limitation to continuous cropping on multifamily farms. On mixed farms, where income was derived from both livestock and grains, the risk of reduced grain yield was less serious. Appropriate use of low quality, erodible soils was often an important consideration of farmers who raised cattle.

Command generation is a process by which input commands are constructed or modified such that the system's response adheres to a set of desired performance specifications. Previously, a variety of command generation techniques such as input shaping have been used to reduce residual vibration, limit transient deflection, conserve fuel or adhere to numerous other performance specifications or performance measures. This dissertation addresses key issues regarding the application of command generation techniques to tethered satellite systems. The three primary objectives of this research are as follows: 1) create analytically commands that will limit the deflection of flexible systems 2) combine command generation and feedback control to reduce the retrieval time of tethered satellites, and 3) develop command generation techniques for spinning tether systems. More specifically, the proposed research addresses six specific aspects of command generation for tethered satellites systems: 1) create command shapers that can limit the trajectory tracking for a mass under PD control to a pre-specified limit in real time 2) create commands analytically that can limit the transient deflection of a model with one rigid-body and one flexible mode during rest-to-rest maneuvers 3) command generation for a 2-D model of earth-pointing tethered satellites without tether flexibility, 4) command generation for a 2-D model of earth-pointing tethered satellites to reduce tether retrieval time and reduce swing angle, 5) command generation for a 3-D model of earth-pointing tethered satellites without tether flexibility, and 6) command generation for improved spin-up of spinning tethered satellite systems. The proposed research is anticipated to advance the state-of-the-art in the field of command generation for tethered satellite systems and will potentially yield improvements in a number of practical satellite and tether applications.

A nanofilm rotation method is developed to study the rotation of nanograins and the formation of various low energy interfaces. Epitaxial NiO and Ag nanofilms are prepared by ion beam sputtering onto the (100), (110), (111) and (112) surfaces of NaCl single crystal. By overlapping of the above films with an angle difference, and annealing at relatively low temperatures the nanograins are induced to rotate till a stable interface is reached. The rotation process and the stable interfaces are determined by transmission electron microscopy. Many new interfaces between mixed planes are found, and their orientation relationships and structures are analyzed. The rotation speed increase with temperature and is fast above 200oC.