Les procédés de mise en forme par enlèvement de matière introduisent, lors de la formation du copeau,des phénomènes complexes et rendent difficiles la maîtrise des grandeurs énergétiques. Des mesuresréalisées à l’aide d’un dynamomètre à six composantes permettent de mieux appréhender ces phénomènes.Ce dynamomètre permet de mesurer l’ensemble des actions mécaniques transmises par la liaison mécaniqueentre la matière usinée (copeau et pièce) et l’outil de coupe. Les mesures révèlent alors la présence demoments, à la pointe de l’outil, non évalués par les modèles de coupe classiques. Cependant, les lois decomportement actuelles ne permettent pas d’exprimer complètement ces phénomènes complexes (gradientsde déformations) lors de la formation du copeau. Actuellement, une modélisation analytique ou numérique etrendant compte de ces phénomènes est donc exclue. Des approches expérimentales ont alors été menées entournage et en perçage. Aujourd’hui ces recherches s’étendent au cas du fraisage.Pour ceci, un nouveau dynamomètre à six composantes adapté au fraisage a été conçu, réalisé etétalonné. Une démarche expérimentale a alors été mise en place afin de modéliser le moment de coupeconsommateur de puissance. Ce moment est alors étudié dans une configuration de coupe orthogonale enfraisage. Un modèle expérimental du moment de coupe est alors proposé. Cette modélisation fait intervenir lasection de copeau réelle instantanée et un nouveau critère énergétique : la densité de moment. Une étude surles paramètres cinématiques réels de l’outil montre la nécessité de prendre en compte la section de copeauinstantanée réelle. Celle–ci est alors calculée à partir de la position réelle de l’outil déduite des donnéescinématiques extraites des codeurs de position des axes et de la broche de la machine outil. Les paramètresinfluents sur la densité de moment ont été mis en évidence par un plan d’expériences et une analyse de lavariance. Une modélisation de ce critère similaire aux coefficients spécifiques de coupe a par la suite étédéveloppée.Enfin, le bilan énergétique de l’opération de coupe étudiée est considéré. Une démarche pratiqued’évaluation rapide de la puissance maximale de coupe est présentée en intégrant la modélisation du momentproposée. L’intérêt et l’importance de la prise en compte du moment de coupe sont alors confirmés pourprédire et définir les énergies mises en jeu par le processus de coupe. / In the cutting process, during the chip formation, complex phenomena occur and the control of theenergy parameters is difficult. Information about these phenomena are given with the measurement of the sixcomponents of the mechanical actions. This dynamometer allows to measure the six mechanical actions (3forces and 3 moments) between the chip, the workpiece and the tool during the chip formation. Themeasurement of the moments at the tooth tip is not inclued in the classical cutting model.However, actual behaviour laws cannot express all the phenomena occurred during the chip formation.Thus, analytical or numerical cutting model taking into account these phenomena is not possible. Previousstudies have been performed in turning and drilling and allow to extend these works to milling.A new six components dynamometer suitable to milling have been designed and calibrated. Anexperimental approach is proposed in order to model the cutting moment involved in the cutting energybalance. The study is performed in orthogonal cutting configurations. A model of cutting moment is proposedand depends on the instantaneous undeformed chip section and a new criteria : the moment density. A studyon real kinematic parameters shows that the instantaneous undeformed chip section have to take intoaccount. The instantaneous undeformed chip section is computed with real position of the tool obtained withthe encoders of linear axes and spindle of the CNC Machine. Design of experiments and variance analysis haveshown influent parameters on the moment density. A model of the moment, close to specific pressurecoefficient, has been developed.Finally, the cutting energy balance of the milling operation used is studied. A practical approach includedthe moment model allow an accurately evaluation of the energy balance. In milling operation, the studyconfirms the cutting moment at the tool tip and shows the necessity to take into account moments in theenergy balance.

It is well established that rarefied flows cannot be properly described by traditional hydrodynamics, namely the Navier-Stokes equations for gas flows, and the Fourier’s law for heat transfer. Considering the significant advancement in miniaturization of electronic devices, where dimensions become comparable with the mean free path of the flow, the It is well established that rarefied flows cannot be properly described by traditional hydrodynamics, namely the Navier-Stokes equations for gas flows, and the Fourier's law for heat transfer. Considering the significant advancement in miniaturization of electronic devices, where dimensions become comparable with the mean free path of the flow, the study of rarefied flows is extremely important. This dissertation includes two main parts. First, we look into the heat transport in solids when the mean free path for phonons are comparable with the length scale of the flow. A set of macroscopic moment equations for heat transport in solids are derived to extend the validity of Fourier's law beyond the hydrodynamics regime. These equations are derived such that they remain valid at room temperature, where the MEMS devices usually work. The system of moment equations for heat transport is then employed to model the thermal grating experiment, recently conducted on a silicon wafer. It turns out that at room temperature, where the experiment was conducted, phonons with high mean free path significantly contribute to the heat transport. These low frequency phonons are not considered in the classical theory, which leads to failure of the Fourier's law in describing the thermal grating experiment. In contrast, the system of moment equations successfully predict the deviation from the classical theory in the experiment, and suggest the importance of considering both low and high frequency phonons at room temperature to capture the experimental results. In the second part of this study, we look into the gas-surface interactions for conventional gas dynamics when the gas flow is rarefied. An extension to the well-known Maxwell boundary conditions for gas-surface interactions are obtained by considering velocity dependency in the reflection kernel from the surface. This extension improves the Maxwell boundary conditions by providing an extra free parameter that can be fitted to the experimental data for thermal transpiration effect in non-equilibrium flows. The velocity dependent Maxwell boundary conditions are derived for the Direct Simulation Monte Carlo (DSMC) method and the regularized 13-moment (R13) equations for conventional gas dynamics. Then, a thermal cavity is considered to test and study the effect of these boundary conditions on the flow formation in the slip and early transition regime. It turns out that using velocity dependent boundary conditions allows us to change the size and direction of the thermal transpiration force, which leads to marked changes in the balance of transpiration forces and thermal stresses in the flow. / Graduate

The existence of the matter in the universe is still an unsolved puzzle. After the Big Bang, both matter and antimatter should have been created in equal amounts, and subsequently annihilated. The leading theories to explain the existence of matter require an imbalance in the production of matter and antimatter in the early universe. This in turn requires CP violation, an asymmetry of the laws of physics between matter and antimatter. cryoEDM is designed to explore the total amount of CP violation and resolve this issue. cryoEDM is a next-generation neutron electric dipole moment search in a commissioning phase of development at the Institut Laue-Langevin, Grenoble. A critical requirement of EDM searches is knowledge of the magnetic environment. This work is concerned with the development, implementation, and performance of the currently operating magnetometry system based on SQUID magnetometers. An analysis scheme to provide magnetometry data over the volume occupied by the neutrons, from measurements using the available magnetometers, is developed. An updated method to calibrate the magnetometers using internal sources of magnetic fields is presented, and found to give good agreement with independent measurements. A new method of calibration using the neutrons as a reference is discussed, and tests on an example arrangement are shown to be promising. Algorithms for detecting and correcting for hardware induced artefacts in the data are produced, and demonstrated to reconstruct the field with good agreement in all but the noisiest environments. A software framework is developed to combine these into a real-time analysis that provides feedback and diagnostics to the experiment. Using this new system the resolution of the magnetometers installed in cryoEDM is found to be limited by the environmental noise, and would give a false EDM signal that is greater than the statistical uncertainty in neutron counting. However, the resolution has been somewhat artificially limited to reduce the susceptibility to the RF interference present. This still allows the magnetometry to act as a useful diagnostic tool on any issues in the current magnetic environment, even if in a sub-optimal configuration. For example, investigation of the magnetic shielding of the experiment finds a reduction in the shielding relative to the design, a situation which is being addressed with the design of additional shielding. Once this shielding is installed the resolution of the magnetometers will improve as well as the slew rate of the SQUIDs, which is found to be lower than the $47,mu extup{Ts}^{-1}$ required to measure AC fields applied during a measurement. The current system can also determine sources of magnetic perturbations created within the experiment, which will require addressing before a full EDM run can be performed. For example, cryogenic effects are observed to occur approximately hourly causing large shifts in the magnetic field. Also operation of valves controlling the flow of neutrons around the experiment are found to produce both AC magnetic fields from the driving motors, and shifts in the field from their movement. Situations which can be resolved by reexamination of installation and operational procedures.

Copper(II) and oxovanadium(IV) ions resemble one another magnetically in having one unpaired electron in their complexes irrespective of their geometrical structures and bond types involved. Copper(II) complexes with antiferromagnetic exchange are well known. On the contrary, antiferromagnetic exchange in oxovanadium(IV) complexes is rather new and not well established. Very few oxovanadium(IV) complexes have been reported to have this anomalous magnetic property. In the investigation of the magnetic properties of oxovanadium(IV) complexes, we have successfully prepared two series of new oxovanadium(IV) complexes with N-salicylideneamino acids.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Systems of magnetic nanowires are considered strong candidates in many technological applications as microwave filters, sensors or devices for data storage. Because of their strong potential as candidates in such applications they became lately the object of many studies. However, due to the very complicated nature of the interwire interactions, their magnetic behavior is very difficult to be interpreted. The main parameter controlling the response of magnetic nanowires assemblies is the aspect ratio of the nanowires that is defined as the ratio of the length to the wire's diameter. In our study we choose to modify the aspect ratio by keeping a constant length of nanowires and modifying the wire's diameter while keeping the same interwire distance. The samples were studied at room temperature, using vibrating sample magnetometer and X-band ferromagnetic resonance experiments. The results are explained taking into account the effects of the magnetostatic interactions and shape anisotropy.

This thesis documents the development of a computational method for wave induced longitudinal bending in ships. First, there will be a discussion about the importance of longitudinal bending in ship design. The paper will then outline the basic physics at work in the system. It will review the wave forcing computation as well as the response of the vessel. It will then document the progression of the program, which was constructed in Fortran 90, as it solves the linear differential equation for the vessel bending caused by an incoming wave. The entire program then appears at the end of the paper. While the current program is not complete the theory behind it is valid and the code can be augmented to include non-linear components in the future.

This thesis is about the relationship between Hurricane Katrina and the television news industry. My goal was to record the experiences of my fellow co-workers at WWL-TV, which was the only local television station to remain on the air throughout the hurricane. I also wanted to perform a review of the news industry up until the point of the storm, in order to analyze any affects the hurricane may have had on news coverage in general.

Reinforced concrete moment-resisting frames are structural systems that work to resist earthquake ground motions through ductile behavior. Their performance is essential to prevent building collapse and loss of life during a seismic event. Seismic building code provisions outline requirements for three categories of reinforced concrete moment-resisting frames: ordinary moment frames, intermediate moment frames, and special moment frames. Extensive research has been conducted on the performance of special moment-resisting frames for areas of high seismic activity such as California. More research is needed on the performance of intermediate moment frames for areas of moderate seismicity because the current code provisions are based on past observation and experience. Adapting dynamic analysis software and applications developed by the Pacific Earthquake Engineering Research (PEER) Group, a representative concrete intermediate moment frame was designed per code provisions and analyzed for specified ground motions in order to calculate the probability of collapse. A parametric study is used to explore the impact of changes in design characteristics and building code requirements on the seismic response and probability of collapse, namely the effect of additional height and the addition of a strong column-weak beam ratio requirement. The results show that the IMF seismic design provisions in ACI 318-08 provide acceptable seismic performance based on current assessment methodology as gravity design appeared to govern the system. Additional height did not negatively impact seismic performance, while the addition of a strong-column weak-beam ratio did not significantly improve results. It is the goal of this project to add insight into the design provisions for intermediate moment frames and to contribute to the technical base for future criteria.

The thesis offers a reappraisal of the process of 'liberation' for homosexual men in France from the events of May 1968 until the onset of the AIDS crisis in 1983. I argue that what we have come to call gay liberation was in fact a complex and contentious process of transformation in the place of homosexual men in French society, a decade marked as much by continuity as it was by change. Gay liberation has been previously understood as a political movement that brought the gay man onto the political stage in spectacular fashion, beginning in the US and sweeping across Western Europe. New political activism is said to have provoked the changes that led to legal equality, culminating in recent marriage legislation. This narrative has solidified into a liberation 'mythology', written mainly by activists themselves, replete with its founding events, language and metaphors. A re-evaluation of the 1970s as a historical moment reveals not the beginning of a triumphant march to equality led by activists, but a transformation in the place of homosexual men in society that contains its own fits and starts, successes and dead ends. The thesis is divided into three parts: Ruptures, continuities and life stories. Part one focuses on aspects of change, the emergence of radical political groups and the burgeoning market catering to gay men. The second part moves to aspects of continuity: the repression of homosexual activity and the persistent stereotyping of homosexuality as the realm of a Parisian literary elite. To close the thesis, part three uses oral history to consider the life stories of men who experienced the period.