Taurus Lightweight Manned Spacecraft Earth orbiting vehicle

The Taurus Lightweight Manned Spacecraft (LMS) was developed by students of the University of Maryland's Aerospace Engineering course in Space Vehicle Design. That course required students to design an Alternative Manned Spacecraft (AMS) to augment or replace the Space Transportation System and meet the following design requirements: (1) launch on the Taurus Booster being developed by Orbital Sciences Corporation; (2) 99.9 percent assured crew survival rate; (3) technology cutoff date of 1 Jan. 1991; (4) compatibility with current space administration infrastructure; and (5) first flight by May 1995. The Taurus LMS design meets the above requirements and represents an initial step toward larger and more complex spacecraft. The Taurus LMS has a very limited application when compared to the space shuttle, but it demonstrates that the U.S. can have a safe, reliable, and low-cost space system. The Taurus LMS is a short mission duration spacecraft designed to place one man into low Earth orbit (LEO). The driving factor for this design was the low payload carrying capabilities of the Taurus Booster - 1300 kg to a 300-km orbit. The Taurus LMS design is divided into six major design sections. The Human Factors section deals with the problems of life support and spacecraft cooling. The Propulsion section contains the Abort System, the Orbital Maneuvering System (OMS), the Reaction Control System (RCS), and Power Generation. The thermal protection systems and spacecraft structure are contained in the Structures section. The Avionics section includes Navigation, Attitude Determination, Data Processing, Communication systems, and Sensors. The Mission Analysis section was responsible for ground processing and spacecraft astrodynamics. The Systems Integration Section pulled the above sections together into one spacecraft, and addressed costing and reliability

Les mesures législatives de lutte contre la discrimination raciale au Québec : Un bilan institutionnel

La plupart des États occidentaux ont mis en place des dispositifs de lutte contre les discriminations qui, au lieu de punir, visent la réparation des préjudices subis par les victimes, en plus de comporter une dimension éducative. Par ailleurs, le redressement « proactif » de certaines inégalités est de plus en plus recherché, par la voie législative notamment. Au Québec, ces trois aspects de la lutte contre le racisme et la discrimination raciale – l’action juridique, l’éducation et le redressement actif des inégalités – sont présents et s’interpénètrent. Sur la base de l’expérience de la Commission des droits de la personne et des droits de la jeunesse, chargée de voir au respect du droit à l’égalité, l’auteur propose un bilan institutionnel de cette action juridique. Il met aussi en lumière certains défis qui se posent aujourd’hui en matière de lutte contre la discrimination raciale. Ce bilan montre que l’action juridique ne peut être envisagée séparément des autres dimensions de la lutte contre la discrimination, soit la dimension éducative et la réduction active des inégalités.Most Western States have set up anti-discrimination mechanisms that aim at compensating victims and educating violators, forsaking the quest for punishment. A proactive correction of inequalities is also increasingly sought through legislative measures. In Québec, the three aspects of the fight against racism and racial discrimination (legal action, education, the proactive correction of inequalities) coexist and influence each other. The Québec Human Rights Commission has been entrusted with the implementation of equality as a legal right. From an institutional perspective based on the experience of the Commission, this article assesses the impact of legal action on anti-discrimination issues. It identifies a number of institutional challenges that today exist in the field. It also suggests that legal action goes hand in hand with other ways of tackling racial discrimination, i.e. education and the active correction of inequalities

Les mouvements racistes et la Charte des droits et libertés de la personne

Au Québec comme ailleurs, les dernières années ont vu naître et croître une « international raciste », nébuleuse d'organisations et de groupuscules qu'unit un refus profond du caractère pluraliste de nos sociétés modernes. L'émergence de mouvements structurés d'extrême droite, de tendance raciste, constitue peut-être la forme la plus exacerbée de cette pathologie politique. Condamnables sur le plan des principes, les activités de ces mouvements soulèvent un problème épineux. Jusqu'où peut-on militer en faveur d'un ordre politique incompatible avec les idéaux d'égalité, de liberté et de dignité sur lesquels se fonde toute société démocratique ? L'auteur explore les dimensions juridiques du problème, à la lumière du texte fondamental qu'est, en droit québécois, la Charte des droits et libertés de la personne. Il analyse, dans un premier temps, la portée des libertés d'opinion, d'expression, de réunion pacifique et d'association garanties par la Charte. Il montre que ces libertés doivent s'exercer dans le respect des valeurs démocratiques, de l’ordre public et du bien-être général, et tente d'en dégager des normes d'action applicables à certains secteurs (dont l'école et le milieu de travail). L'auteur analyse ensuite la portée normative du droit à l'égalité, dont il fait ressortir tant les potentialités sur le plan des recours disponibles que les limites inhérentes à la formulation actuelle de la Charte. À travers ce portrait à la fois descriptif et critique du droit positif québécois transparaît l'intérêt d'une approche de l’extrémisme raciste fondée sur la Charte, distincte dans ses ressorts fondamentaux d'un droit pénal parfois peu adapté à la réalité du phénomène.In Quebec as elsewhere, recent years have seen the birth and growth of organizations and splinter groups that share a profound refusal of the pluralistic character of our modern societies. The emergence of organized extremist right-wing movements sporting racist tendencies, constitutes perhaps the most exacerbated form of this political pathology. Although reprehensible from the standpoint of principles, the activities of these movements present a delicate problem for all democratic societies. How far can one conceivably militate in favour of apolitical order incompatible with the ideals of equality, liberty and dignity upon which that society is founded ? The author deals with the legal dimensions of this problem in light of the Charter of Human Rights and Freedoms, the fundamental text covering such matters in the Quebec legal system. First, he analyzes the scope of freedoms of opinion, expression, peaceful assembly and association guaranteed under the Charter. He demonstrates how these freedoms must be exercised while respecting democratic values, public order and general well-being and he attempts to synthesize action guidelines applicable to various sectors (including schools and the workplace). The author then analyzes the normative scope of the right to equality, illustrating, both its potentialities regarding available recourses and its inherent limits under the present formulation of the Charter. Throughout this descriptive and critical portrayal of our substantive law transpires the interest of an approach to racist extremism based on the Charier, whose distinct mechanisms are sometimes better adapted to the activities of racist organizations than those of criminal law

Techniques for Generating Centimetric Drops in Microgravity and Application to Cavitation Studies

This paper describes the techniques and physical parameters used to produce stable centimetric water drops in microgravity, and to study single cavitation bubbles inside such drops (Parabolic Flight Campaigns, European Space Agency ESA). While the main scientific results have been presented in a previous paper, we shall herein provide the necessary technical background, with potential applications to other experiments. First, we present an original method to produce and capture large stable drops in microgravity. This technique succeeded in generating quasi-spherical water drops with volumes up to 8 ml, despite the residual g-jitter. We find that the equilibrium of the drops is essentially dictated by the ratio between the drop volume and the contact surface used to capture the drop, and formulate a simple stability criterion. In a second part, we present a setup for creating and studying single cavitation bubbles inside those drops. In addition, we analyze the influence of the bubble size and position on the drop behaviour after collapse, i.e. jets and surface perturbations

Energy partition at the collapse of spherical cavitation bubbles

Spherically collapsing cavitation bubbles produce a shock wave followed by a rebound bubble. Here we present a systematic investigation of the energy partition between the rebound and the shock. Highly spherical cavitation bubbles are produced in microgravity, which suppress the buoyant pressure gradient that otherwise deteriorates the sphericity of the bubbles. We measure the radius of the rebound bubble and estimate the shock energy as a function of the initial bubble radius (2-5.6 mm) and the liquid pressure (10-80 kPa). Those measurements uncover a systematic pressure dependence of the energy partition between rebound and shock. We demonstrate that these observations agree with a physical model relying on a first-order approximation of the liquid compressibility and an adiabatic treatment of the non-condensable gas inside the bubble. Using this model we find that the energy partition between rebound and shock is dictated by a single non-dimensional parameter $\xi = \Delta p\gamma^6/[{p_{g0}}^{1/\gamma} (\rho c^2)^{1-1/\gamma}]$, where $\Delta p=p_\infty-p_v$ is the driving pressure, $p_{\infty}$ is the static pressure in the liquid, $p_v$ is the vapor pressure, $p_{g0}$ is the pressure of the non-condensable gas at the maximal bubble radius, $\gamma$ is the adiabatic index of the non-condensable gas, $\rho$ is the liquid density, and $c$ is the speed of sound in the liquid.Comment: 7 pages, 7 figure