72,443 research outputs found

    The Dynamics of Car Sales: A Discrete Choice Approach

    Get PDF

    Enforcing the rights and freedoms of disabled people: the role of transnational law (Part I)

    Get PDF
    In Part I of this article we examined the actual and potential application of global international law (GIL) to the development of rights and freedoms for people with disabilities. We concluded that there is currently no binding and accessible GIL instrument that specifically relates to this group. Instead, an emphasis was placed upon those instruments that have a generic application to human rights and a clear potential application to the protection of disability rights primarily through their provisions relating to non-discrimination. Moreover, we stressed that the instruments of GIL also have the potential to provide an indirect benefit to disabled people as tools of influence and persuasion in the development of non-discrimination and affirmative action empowerment programmes at both a national and international level. In Part II, we apply a similar analysis to the opportunities offered by European international law (EIL).</p

    Reversible and irreversible evolution of a condensed bosonic gas

    Full text link
    We have formulated a kinetic theory for a condensed atomic gas in a trap, i.e., a generalized Gross-Pitaevskii equation, as well as a quantum-Boltzmann equation for the normal and anomalous fluctuations [R. Walser et al., Phys. Rev. A, 59, 3878 (1999)]. In this article, the theory is applied to the case of an isotropic configuration and we present numerical and analytical results for the reversible real-time propagation, as well as irreversible evolution towards equilibrium.Comment: 15 pages RevTeX, 8 figures, reviewed PRA resubmissio

    Theory of Spin-Split Cyclotron Resonance in the Extreme Quantum Limit

    Full text link
    We present an interpretation of recent cyclotron resonance experiments on the two-dimensional electron gas in GaAs/AlGaAs heterostructures. We show that the observed dependence of the resonance spectrum on Landau level occupancy and temperature arises from the interplay of three factors: spin-splitting of the cyclotron frequency; thermal population of the two spin states; and coupling of the resonances for each spin orientation by Coulomb interactions. In addition, we derive an ff-sum rule which allows spin polarisation to be determined directly from resonance spectra.Comment: 10 pages (revtex 3.0) + 4 uuencoded postscript figure

    Underwater space suit pressure control regulator

    Get PDF
    A device is reported for regulating the pneumatic pressure in a ventilated space suit relative to the pressure imposed on the suit when being worn by a person underwater to simulate space environment for testing and experimentation. A box unit located on the chest area of the suit comprises connections for suit air supply and return lines and carries a regulator valve that stabilizes the air pressure differential between the inside and outside of the suit. The valve and suit pressure is controlled by the suit occupant and the valve includes a mechanism for quickly dumping the suit pressure in case of emergency. Pressure monitoring and relief devices are also included in the box unit

    SIRU development. Volume 1: System development

    Get PDF
    A complete description of the development and initial evaluation of the Strapdown Inertial Reference Unit (SIRU) system is reported. System development documents the system mechanization with the analytic formulation for fault detection and isolation processing structure; the hardware redundancy design and the individual modularity features; the computational structure and facilities; and the initial subsystem evaluation results

    Quantum Kinetic Theory for a Condensed Bosonic Gas

    Full text link
    We present a kinetic theory for Bose-Einstein condensation of a weakly interacting atomic gas in a trap. Starting from first principles, we establish a Markovian kinetic description for the evolution towards equilibrium. In particular, we obtain a set of self-consistent master equations for mean fields, normal densities, and anomalous fluctuations. These kinetic equations generalize the Gross-Pitaevskii mean-field equations, and merge them consistently with a quantum-Boltzmann equation approach.Comment: 15 pages, no figures; reviewed version; to be published in PR
    • …
    corecore