10,493 research outputs found
Aerodynamic characteristics determined during development of the Apollo launch escape vehicle configuration
Aerodynamic characteristics determined during development of Apollo launch escape vehicle configuration in wind tunnel test
Crystal truncation rods in kinematical and dynamical x-ray diffraction theories
Crystal truncation rods calculated in the kinematical approximation are shown
to quantitatively agree with the sum of the diffracted waves obtained in the
two-beam dynamical calculations for different reflections along the rod. The
choice and the number of these reflections are specified. The agreement extends
down to at least of the peak intensity. For lower intensities,
the accuracy of dynamical calculations is limited by truncation of the electron
density at a mathematically planar surface, arising from the Fourier series
expansion of the crystal polarizability
Debris/ice/TPS assessment and integrated photographic analysis for Shuttle Mission STS-56
The Debris Team developed and implemented measures to control damage from debris in the Shuttle operational environment and to make the control measures a part of routine launch flows. These measures include engineering surveillance during vehicle processing and closeout operations, facility and flight hardware inspections before and after launch, and photographic analysis of mission events. Photographic analyses of mission imagery from launch, on-orbit, and landing provide significant data in verifying proper operation of systems and evaluating anomalies. In addition to the Kennedy Space Center (KSC) Photo/Video Analysis, reports from JSC, MSFC, and Rockwell International--Downey are also included in this document to provide an integrated assessment of the mission
Spin-polarized tunneling spectroscopy in tunnel junctions with half-metallic electrodes
We have studied the magnetoresistance (TMR) of tunnel junctions with
electrodes of La2/3Sr1/3MnO3 and we show how the variation of the conductance
and TMR with the bias voltage can be exploited to obtain a precise information
on the spin and energy dependence of the density of states. Our analysis leads
to a quantitative description of the band structure of La2/3Sr1/3MnO3 and
allows the determination of the gap delta between the Fermi level and the
bottom of the t2g minority spin band, in good agreement with data from
spin-polarized inverse photoemission experiments. This shows the potential of
magnetic tunnel junctions with half-metallic electrodes for spin-resolved
spectroscopic studies.Comment: To appear in Physical Review Letter
Finite type approximations of Gibbs measures on sofic subshifts
Consider a H\"older continuous potential defined on the full shift
A^\nn, where is a finite alphabet. Let X\subset A^\nn be a specified
sofic subshift. It is well-known that there is a unique Gibbs measure
on associated to . Besides, there is a natural nested
sequence of subshifts of finite type converging to the sofic subshift
. To this sequence we can associate a sequence of Gibbs measures
. In this paper, we prove that these measures weakly converge
at exponential speed to (in the classical distance metrizing weak
topology). We also establish a strong mixing property (ensuring weak
Bernoullicity) of . Finally, we prove that the measure-theoretic
entropy of converges to the one of exponentially fast.
We indicate how to extend our results to more general subshifts and potentials.
We stress that we use basic algebraic tools (contractive properties of iterated
matrices) and symbolic dynamics.Comment: 18 pages, no figure
Plasma binding proteins for platelet-derived growth factor that inhibit its binding to cell-surface receptors.
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