3,252 research outputs found

    Composite powerplant and shroud therefor Patent

    Get PDF
    Shrouded composite propulsion system configuratio

    Integral coolant channels supply made by melt-out method

    Get PDF
    Melt-out method of constructing strong, pressure-tight fluid coolant channels for chambers is accomplished by cementing pins to the surface and by depositing a melt-out material on the surface followed by two layers of epoxy-resin impregnated glass fibers. The structure is heated to melt out the low-melting alloy

    Attitude and propellant flow control system and method Patent

    Get PDF
    Attitude and propellant flow control system for liquid propellant rocket vehicle

    Space Propulsion Technology Program Overview

    Get PDF
    The topics presented are covered in viewgraph form. Focused program elements are: (1) transportation systems, which include earth-to-orbit propulsion, commercial vehicle propulsion, auxiliary propulsion, advanced cryogenic engines, cryogenic fluid systems, nuclear thermal propulsion, and nuclear electric propulsion; (2) space platforms, which include spacecraft on-board propulsion, and station keeping propulsion; and (3) technology flight experiments, which include cryogenic orbital N2 experiment (CONE), SEPS flight experiment, and cryogenic orbital H2 experiment (COHE)

    Copyright, Technology & The Boston Strangler: The Seventh Circuit and the Future of Online Music Access

    Get PDF
    The United States Supreme Court previously ruled that recording television programs or movies using Betamax or VHS tapes does not constitute copyright infringement. However, the Supreme Court recently held that downloading music from a peer-to-peer (P2P) file-sharing network does constitute copyright infringement. Thus, federal district court decisions are now targeting individuals who illegally download music from these networks and entering large monetary judgments against them. The U.S. Court of Appeals for the Seventh Circuit is upholding these judgments. This article discusses the difference between video taping and downloading and why is there a discrepancy in terms of copyright law

    The Degasperis-Procesi equation as a non-metric Euler equation

    Full text link
    In this paper we present a geometric interpretation of the periodic Degasperis-Procesi equation as the geodesic flow of a right invariant symmetric linear connection on the diffeomorphism group of the circle. We also show that for any evolution in the family of bb-equations there is neither gain nor loss of the spatial regularity of solutions. This in turn allows us to view the Degasperis-Procesi and the Camassa-Holm equation as an ODE on the Fr\'echet space of all smooth functions on the circle.Comment: 17 page

    Non-destructive imaging of an individual protein

    Full text link
    The mode of action of proteins is to a large extent given by their ability to adopt different conformations. This is why imaging single biomolecules at atomic resolution is one of the ultimate goals of biophysics and structural biology. The existing protein database has emerged from X-ray crystallography, NMR or cryo-TEM investigations. However, these tools all require averaging over a large number of proteins and thus over different conformations. This of course results in the loss of structural information. Likewise it has been shown that even the emergent X-FEL technique will not get away without averaging over a large quantity of molecules. Here we report the first recordings of a protein at sub-nanometer resolution obtained from one individual ferritin by means of low-energy electron holography. One single protein could be imaged for an extended period of time without any sign of radiation damage. Since ferritin exhibits an iron core, the holographic reconstructions could also be cross-validated against TEM images of the very same molecule by imaging the iron cluster inside the molecule while the protein shell is decomposed
    • …
    corecore