5,210 research outputs found

    Formulation of consumables management models. Volume 1: Mission planning

    Get PDF
    Development of an STS (Space Transportation System) interactive computer program MPP (Mission Planning Processor) working model was conducted. A summary of the computer program development and those supporting tasks conducted is presented. Development of the MPP Computer Program is discussed. This development was supported by several parallel tasks. These tasks either directly supported the program development, or provided information for future application and/or modification to the program in relation to the flight planning and flight operations of the STS and advanced spacecraft. The supporting tasks also included development of a Space Station MPP to demonstrate the applicability of the analytical methods developed under this RTOP to more advanced spacecraft than the STS

    Layered Quantum Hall Insulators with Ultracold Atoms

    Full text link
    We consider a generalization of the 2-dimensional (2D) quantum-Hall insulator to a non-compact, non-Abelian gauge group, the Heisenberg-Weyl group. We show that this kind of insulator is actually a layered 3D insulator with nontrivial topology. We further show that nontrivial combinations of quantized transverse conductivities can be engineered with the help of a staggered potential. We investigate the robustness and topological nature of this conductivity and connect it to the surface modes of the system. We also propose a simple experimental realization with ultracold atoms in 3D confined to a 2D square lattice with the third dimension being mapped to a gauge coordinate.Comment: 6 page

    A first order Tsallis theory

    Full text link
    We investigate first-order approximations to both i) Tsallis' entropy SqS_q and ii) the SqS_q-MaxEnt solution (called q-exponential functions eqe_q). It is shown that the functions arising from the procedure ii) are the MaxEnt solutions to the entropy emerging from i). The present treatment is free of the poles that, for classic quadratic Hamiltonians, appear in Tsallis' approach, as demonstrated in [Europhysics Letters {\bf 104}, (2013), 60003]. Additionally, we show that our treatment is compatible with extant date on the ozone layer.Comment: 4 figures adde

    Reciprocity of Networks with Degree Correlations and Arbitrary Degree Sequences

    Full text link
    Although most of the real networks contain a mixture of directed and bidirectional (reciprocal) connections, the reciprocity rr has received little attention as a subject of theoretical understanding. We study the expected reciprocity of networks with an arbitrary degree sequence and a broad class of degree correlations by means of statistical ensemble approach. We demonstrate that degree correlations are crucial to understand the reciprocity in real networks and a hierarchy of correlation contributions to rr is revealed. Numerical experiments using novel network randomization methods show very good agreement to our analytical estimations.Comment: 8 pages, 3 figures, added a new table and a new figure, accepted for publication in Phys.Rev.
    corecore