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<p>This thesis isconcerned with Jean-Jacques Rousseau's treatment of the effect of political actions on the human problem. Four emphases in that treatment are considered.</p> <p> In the first place, Rousseau is concerned about what can be called a tension between nature and society, a tension which is basic to the human situation as he sees it. He wants to distinguish between good nature and bad society and between a good, natural self and a bad, social self.</p> <p>In the second place, closer scrutiny reveals that the tension between nature and society hinges on the problem of passion. Rousseau wants further to distinguish between good, natural passions and bad, social passions, and the political problem is always and everywhere the same: how to control the bad, social passions.</p> <p>In the third place, there is a dialectical unity in Rousseau's treatment of the tension between nature and society. Contrary to many interpretations, he does not treat nature and society as concrete abstractions but only as hypothetical abstractions. His writings are consistent; he is both idealistic and realistic, theoretical and practical, optimistic and pessimistic.</p> <p>In the fourth place, whether Rousseau is talking about individuals or societies there is a continuing emphasis on an organic cycle of life and death. An ironical situation develops in respect of political actions. that affect the tension between nature and society. Political actions have to be as natural as possible, but they confront nature as limit, in the form of a natural tendency on the part of individuals to place their own interests ahead of those of their fellows. Rousseau envisions no way out of that vicious circle, and we are, therefore, faced with the prospect of a never-ending cycle of life and death of all organic bodies, including bodies politic.</p> <p>Those four emphases inform the structure of this thesis. The thesis is divided into a series of chapters dealing with different aspects of the tension between nature and society. The thesis begins with a discussion of how Rousseau himself dealt with the problems that he faced in his life, given that he considered himself an exemplar of what it meant to be both natural and human. The thesis then looks at the tension between nature and society viewed as hypothetical abstractions, after which the tension is considered from an historical perspective. </p> <p>The centrepiece of the thesis consists of a discussion of how political actions can affect the tension between nature and society, through communitarian and egalitarian politics. The cycle is completed by showing why, in the long run, all bodies politic are bound to decay and die, bearing in mind, however, that regeneration is always possible.</p> / Thesis / Doctor of Philosophy (PhD)

The liver is one of the most frequently injured abdominal organs in motor vehicle collisions. Although previous studies have quantified the tensile failure properties of human liver parenchyma at 48hrs postmortem, it is currently unknown how the material properties change between time of death and 48hrs postmortem. Therefore, the purpose of this study was to quantify the effects of postmortem degradation on the tensile material properties of bovine liver parenchyma when stored in DMEM or saline. Fourteen fresh bovine livers were obtained from a local slaughter house and stored in either DMEM or saline as large blocks, small blocks, or slices of tissue. Multiple parenchyma dog-bone samples from each liver were tested once to failure at three time points: ~6hrs, ~24hrs, and ~48hrs postmortem. The data were then analyzed to determine if there were significant changes in the material properties with respect to postmortem time. The results showed that the failure strain decreased significantly between 6hrs and 48hrs after death when stored as large blocks in saline. Conversely, neither the failure stress nor failure strain changed significantly with respect to postmortem time when stored as large blocks in DMEM. The modulus did not significantly change for tissue stored as large blocks in either fluid. Preliminary results indicated that reducing the tissue storage size had a negative effect on the material properties and cellular architecture. Overall, this study illustrated that the effects of postmortem liver degradation varied with respect to the preservation fluid, storage time, and storage block size. / MS

The most common fastening technique that is used to connect the components of wooden pallets together are helically or annularly threaded pallet nails. Pallet nails create a strong durable connection and increase manufacturing efficiency for a low cost. However, nails can also cause iron staining, wood splitting, and when exposed can cause product damage or personnel injury. Using adhesives could be a solution to these problems, but only if the adhesives' strength and durability is comparable or higher than nails. The objective of the study was to investigate the tensile and shear strength of pallet connections secured using commercially available wood adhesives and compare their performance to pallet connections secured using common pallet nails. The lowest pre-compression pressure resulted in the best tension and shear performance for a solvent based construction adhesive (SBCA). The pre-compression pressure did not have any practical effect on the performance of the two-part emulsion polymer isocyanate (EPI) adhesive. Samples made with the solvent based construction adhesive (SBCA) had greater strength and energy at failure than nailed samples. Meanwhile, the samples made with the two-part emulsion polymer isocyanate (EPI) adhesive had equal or greater strength than nailed samples, except for during the tension parallel to the grain tests in which they had equal or lower strength. / MS / The most common technique used to connect the components of wooden pallets together is nails. Pallet nails create a strong connection with high manufacturing efficiency for a low cost. However, nails can cause iron staining, wood splitting, and when exposed can cause product damage or personnel injury. Using adhesives could be a solution to these problems, but only if the adhesives’ strength and durability is comparable or higher than nails. The objective of this study was to investigate the tensile and shear strength of pallet connections when secured using commercially available wood adhesives and compare its performance to pallet connections secured by using common pallet nails. The lowest pre-compression pressure tested resulted in the best overall performance for a solvent based construction adhesive (SBCA); meanwhile, pre-compression pressure did not have any practical effect on the performance of the two-part emulsion polymer isocyanate (EPI) adhesive tested. Therefore, using a lower pre-compression pressure would provide adequate performance and could also improve the ease of manufacturing and potentially reduce overall costs. Based on the tests conducted it was found that the solvent based construction adhesive (SBCA) demonstrated the best performance of all connection methods and could be a potential replacement for nails. More tests, such as weathering and impact, should be conducted to determine the full limitations of the adhesive in use.

A tension control algorithm for the deployment of a unmanned ground vehicle from an autonomous helicopter is designed and tested in this thesis. The physical hardware which the controller will run on is detailed. The plant model and underlying controllers are derived and modeled. The tension controller algorithm is selected, derived, and modeled. The parameters of the tension controller are chosen and simulations are run with the chosen parameters. The tension control algorithm is run on the physical hardware, successfully demonstrating tension control on a ground vehicle. Robustness simulations are run for a change in the radius of the spool and the length of the tether. Lastly, Future work is outlined on several paths to move forward with the tension controller. / Master of Science

This study investigates the status of biofeedback treatment and locus of control (LOC) affiliation on the reduction of tension headache. Three LOC groups designated as internals, powerful-other externals and chance externals (using Wallston and Wallston's, 1978, Multidimensional Health Locus of Control Scale) were administered an eight week electromyogram (EMG) frontalis muscle biofeedback training program using an Autogen 1700 biofeedback unit. Subjects were 12 female and four male undergraduate students who had a history of tension headache. Results indicated no significant difference in frontalis muscle tension between the beginning and end of sessions in either a biofeedback or self-control condition for any of the LOC groups. Further, there was no significant difference among LOC groups in ability to reduce muscle tension in either the training or self-control condition. Finally, neither biofeedback training nor LOC groups were significant predictors of headache reduction. Extreme within-group variability and small sample size affected study findings and these and other implications for future research are discussed.

Les milieux granulaires présentent une grande diversité de comportements physiques que l'on peut relier aux différents états "conventionnels" de la matière : solide, liquide ou gaz. Les travaux décrits dans ce manuscrit se concentrent sur les écoulements granulaires denses présentant de nombreuses analogies avec les liquides moléculaires. Les expériences présentées dans ce manuscrit sont réalisées en utilisant des jets granulaires s'écoulant d'un réservoir, dans l'air et sous l'effet de la gravité. Quelques propriétés de tels jets sont étudiées, notamment l'évolution du diamètre au cours de la propagation. L'évolution de cette grandeur permet une description des jets granulaires comme des fluides incompressibles dans une certaine gamme de diamètres de sortie D et de diamètres des particules d, résumés en une grandeur réduite : le rapport d'aspect D/d. Lorsque ce dernier est inférieur à une grandeur critique proche de 15, les jets granulaires cessent de se comporter comme des liquides incompressibles et sont alors décrits comme des gaz en expansion.La transition entre les deux régimes d'écoulements est expliquée par un modèle faisant intervenir l'équilibre entre la température granulaire et sa dissipation par l'inélasticité des collisions entre les billes constituant le milieu granulaire. En utilisant les mesures de la température granulaire accessibles à la paroi dans le réservoir, ce modèle permet d'obtenir les profils de température et de fraction volumique du milieu en fonction du rapport d'aspect ainsi que leurs valeurs moyennes, présentant un bon accord avec les mesures de la fraction volumique en sortie du réservoir.Dans le régime "liquide" des jets granulaires mis en évidence ici, une tension de surface effective est mesurée par l'étude d'une instabilité similaire à celle de Rayleigh-Plateau. En soumettant le jet à une oscillation verticale apparaît une modulation du diamètre du jet dont il est possible d'étudier l'évolution au cours du temps. La mesure des taux de croissance des modes instables excités permet d'établir la relation de dispersion et d'obtenir une tension de surface effective dans les jets granulaires. Il est montré que cette tension de surface effective décroit lorsque la taille des particules augmente, décroit lorsque la pression de l'air ambiant diminue et augmente avec la distance de propagation.Le mécanisme proposé pour expliquer l'origine de cette tension de surface effective est l'interaction entre le jet granulaire et l'air ambiant. Les profils de vitesse de l'air entraîné par le jet sont mesurés pour différentes diamètres de particules, différentes pression ambiantes et différentes distances de propagation. L'entraînement de l'air et les profils de vitesses sont utilisés pour définir certaines forces s'exerçant sur les billes et construire une tension de surface effective : l'ordre de grandeur de cette tension de surface est incompatible avec les mesures réalisées précédemment. Une mesure de la pression de l'air à l'intérieur du jet granulaire permet d'obtenir une force exercée par la perméation de l'air à travers les pores du jet dont l'ordre de grandeur est correct. / Granular media exhibit a broad range of behaviours that can be related to the common states of matter: solid, liquid and gaseous. The experiments described in this thesis focus on dense granular flows ad their analogies with molecular liquid flows.The work presented focuses on granular material flowing from a reservoir, in ambient air under the effect of gravity. Some properties of such jets are presented, among them the evolution of the diameter of the jet along propagation. This evolution allows one to describe granular jets as incompressible liquid jets for a certain range of parameters D (exit diameter) and d (beads diameter). When using a reduced variable D/d (the aspect ratio), a transition appears close to a critical value (approx. 15) below which the granular jet exhibit a gas-like behaviour.This transition is explained using a model supposing balance between the heat flux (from the granular temperature imposed at the wall of the reservoir) and its dissipation through inelastic collisions between the beads in the granular medium. This model allows one to compute the temperature and volume fraction profiles as well as their mean values which are in good agreement with the experimental measurements (volume fraction at the exit).In the "liquid" regime defined previously, an effective surface tension is measured by studying the unstable modes of a Rayleigh-Plateau like instability. This instability is obtained by imposing a vertical oscillation on the jet which induces a diametrical modulation whose evolution is measured. Measurements of the growth rates of these unstable modes leads to the dispersion relation $\omega (kr_{0})$ and to an effective granular surface tension. This surface tension shows a diminution when the beads' size increases, a diminution when the air pressure is reduced and a growth along propagation.The proposed mechanism explaining this effective surface tension is the interaction between the granular jet and the surrounding air. Air velocity profiles are measured for different beads diameters, different air pressures and different distances below the outlet. Using these velocity profiles, various forces exerted on the beads are calculated, leading to a surface tension whose order of magnitude is lower than the one measured through the Rayleigh-Plateau instability. The right order of magnitude can be obtained by considering the air permeation through the pores on the surface the jet and the force exerted along the surface of said pores.