11,648 research outputs found

    Attitude control system for sounding rockets Patent

    Get PDF
    Development of attitude control system for sounding rocket stabilization during ballistic phase of fligh

    Utility operational experience on the NASA/DOE MOD-0A 200-kW wind turbine

    Get PDF
    The Mod-0A 200 wind turbine was designed and fabricated as part of the Federal Wind Energy Program. Early wind turbine operation and performance data were obtained while gaining initial experience in the operation of large, horizontal axis wind turbines in typical utility environments. The Mod-0A wind turbine was turned over to the Town of Clayton Light and Water Plant, Clayton, NM, for utility operation and on December 31, 1978, the machine had completed ten months of utility operation. The machine is described and the recent operational experience at Clayton, NMis documented

    Catholic and charismatic : a study in personality theory within Catholic congregations

    Get PDF
    This study set out to conceptualise and measure Charismatic orientation (openness to charismatic experience) and traditional Catholic orientation (Catholic identity) among a sample of 670 Catholic churchgoers in order to test whether attachment to Catholic Charismatic Renewal strengthened or weakened the sense of traditional Catholic identity among churchgoing Catholics. This research question was set within the broader consideration of the location of Charismatic orientation and Catholic orientation within Eysenck's three dimensional model of personality. The data revealed a strong positive association between Charismatic experience and Catholic identity. Higher scores on the index of Charismatic orientation were associated with higher extraversion scores, with higher neuroticism scores, and with higher levels of mass attendance and personal prayer. Higher scores on the index of Catholic orientation were associated with being female, being older, higher neuroticism scores, and higher levels of mass attendance and personal prayer

    Torsion and bending of nucleic acids studied by subnanosecond time-resolved fluorescence depolarization of intercalated dyes

    Get PDF
    Subnanosecond time‐resolved fluorescence depolarization has been used to monitor the reorientation of ethidium bromide intercalated in native DNA, synthetic polynucleotide complexes, and in supercoiled plasmid DNA. The fluorescence polarization anisotropy was successfully analyzed with an elastic model of DNA dynamics, including both torsion and bending, which yielded an accurate value for the torsional rigidity of the different DNA samples. The dependence of the torsional rigidity on the base sequence, helical structure, and tertiary structure was experimentally observed. The magnitude of the polyelectrolyte contribution to the torsional rigidity of DNA was measured over a wide range of ionic strength, and compared with polyelectrolyte theories for the persistence length. We also observed a rapid initial reorientation of the intercalated ethidium which had a much smaller amplitude in RNA than in DNA

    Time-resolved spectroscopy of macromolecules: Effect of helical structure on the torsional dynamics of DNA and RNA

    Get PDF
    The torsional rigidity of DNA and RNA is measured via the fluorescence depolarization technique

    Lower bound for energies of harmonic tangent unit-vector fields on convex polyhedra

    Full text link
    We derive a lower bound for energies of harmonic maps of convex polyhedra in R3 \R^3 to the unit sphere S2,S^2, with tangent boundary conditions on the faces. We also establish that CC^\infty maps, satisfying tangent boundary conditions, are dense with respect to the Sobolev norm, in the space of continuous tangent maps of finite energy.Comment: Acknowledgment added, typos removed, minor correction

    Zero area singularities in general relativity and inverse mean curvature flow

    Full text link
    First we restate the definition of a Zero Area Singularity, recently introduced by H. Bray. We then consider several definitions of mass for these singularities. We use the Inverse Mean Curvature Flow to prove some new results about the mass of a singularity, the ADM mass of the manifold, and the capacity of the singularity.Comment: 13 page

    Dynamical density functional theory for the dewetting of evaporating thin films of nanoparticle suspensions exhibiting pattern formation

    Get PDF
    Recent experiments have shown that the striking structure formation in dewetting films of evaporating colloidal nanoparticle suspensions occurs in an ultrathin `postcursor' layer that is left behind by a mesoscopic dewetting front. Various phase change and transport processes occur in the postcursor layer, that may lead to nanoparticle deposits in the form of labyrinthine, network or strongly branched `finger' structures. We develop a versatile dynamical density functional theory to model this system which captures all these structures and may be employed to investigate the influence of evaporation/condensation, nanoparticle transport and solute transport in a differentiated way. We highlight, in particular, the influence of the subtle interplay of decomposition in the layer and contact line motion on the observed particle-induced transverse instability of the dewetting front.Comment: 5 pages, 5 figure

    Variational quantum Monte Carlo simulations with tensor-network states

    Get PDF
    We show that the formalism of tensor-network states, such as the matrix product states (MPS), can be used as a basis for variational quantum Monte Carlo simulations. Using a stochastic optimization method, we demonstrate the potential of this approach by explicit MPS calculations for the transverse Ising chain with up to N=256 spins at criticality, using periodic boundary conditions and D*D matrices with D up to 48. The computational cost of our scheme formally scales as ND^3, whereas standard MPS approaches and the related density matrix renromalization group method scale as ND^5 and ND^6, respectively, for periodic systems.Comment: 4+ pages, 2 figures. v2: improved data, comparisons with exact results, to appear in Phys Rev Let

    Geometric phases and anholonomy for a class of chaotic classical systems

    Full text link
    Berry's phase may be viewed as arising from the parallel transport of a quantal state around a loop in parameter space. In this Letter, the classical limit of this transport is obtained for a particular class of chaotic systems. It is shown that this ``classical parallel transport'' is anholonomic --- transport around a closed curve in parameter space does not bring a point in phase space back to itself --- and is intimately related to the Robbins-Berry classical two-form.Comment: Revtex, 11 pages, no figures
    corecore