8,455 research outputs found
Control device Patent
Device for controlling rotary potentiometer mounted on aircraft steering wheel or aileron contro
Thumb-actuated control device
Rotary potentiometer device on the spoke of an aircraft steering wheel provides servo control of certain flight characteristics with no visual attention and a minimum of operational movement
Variational calculations for K-few-nucleon systems
Deeply bound KNN, KNNN and KNNNN states are discussed. The effective force
exerted by the K meson on the nucleons is calculated with static nucleons. Next
the binding energies are obtained by solving the Schrodinger equation or by
variational calculations.
The dominant attraction comes from the S-wave Lambda(1405) and an additional
contribution is due to Sigma(1385). The latter state is formed at the nuclear
peripheries and absorbs a sizable piece of the binding energy. It also
generates new branches of quasi-bound states. The lowest binding energies based
on a phenomenological KN input fall into the 40-80 MeV range for KNN, 90-150
MeV for KNNN and 120-220 MeV for K-alpha systems. The uncertainties are due to
unknown KN interactions in the distant subthreshold energy region.Comment: 19 pages, 1 figur
First Nonperturbative Test of a Relativistic Heavy Quark Action in Quenched Lattice QCD
We perform a numerical test of a relativistic heavy quark(RHQ) action,
recently proposed by Tsukuba group, in quenched lattice QCD at
fm. With the use of the improvement parameters previously determined at
one-loop level for the RHQ action, we investigate a restoration of rotational
symmetry for heavy-heavy and heavy-light meson systems around the charm quark
mass. We focused on two quantities, the meson dispersion relation and the
pseudo-scalar meson decay constants. It is shown that the RHQ action
significantly reduces the discretization errors due to the charm quark mass. We
also calculate the S-state hyperfine splittings for the charmonium and
charmed-strange mesons and the meson decay constant. The remaining
discretization errors in the physical quantities are discussed.Comment: 21 pages, 16 figures. A reference and a comment added, a major
modification in appendix, several minor changes in the abstract and the main
text. Errors in affiliation are corrected. Version appeared in JHE
Pole dynamics for the Flierl-Petviashvili equation and zonal flow
We use a systematic method which allows us to identify a class of exact
solutions of the Flierl-Petvishvili equation. The solutions are periodic and
have one dimensional geometry. We examine the physical properties and find that
these structures can have a significant effect on the zonal flow generation.Comment: Latex 40 pages, seven figures eps included. Effect of variation of
g_3 is studied. New references adde
Spin foam model for Lorentzian General Relativity
We present a spin foam formulation of Lorentzian quantum General Relativity.
The theory is based on a simple generalization of an Euclidean model defined in
terms of a field theory over a group. Its vertex amplitude turns out to be the
one recently introduced by Barrett and Crane. As in the case of its Euclidean
relatives, the model fully implements the desired sum over 2-complexes which
encodes the local degrees of freedom of the theory.Comment: 8 pages, 1 figur
Resolving Exceptional Configurations
In lattice QCD with Wilson fermions, exceptional configurations arise in the
quenched approximation at small quark mass. The origin of these large
previously uncontrolled lattice artifacts is identified. A simple well-defined
procedure (MQA) is presented which removes the artifacts while preserving the
correct continuum limit.Comment: Talk presented by E. Eichten at Lattice 97, Edinburgh(UK), July97. 6
pages, LaTeX, 1 table, 5 figure
Space Shuttle program communication and tracking systems interface analysis
The Space Shuttle Program Communications and Tracking Systems Interface Analysis began April 18, 1983. During this time, the shuttle communication and tracking systems began flight testing. Two areas of analysis documented were a result of observations made during flight tests. These analyses involved the Ku-band communication system. First, there was a detailed analysis of the interface between the solar max data format and the Ku-band communication system including the TDRSS ground station. The second analysis involving the Ku-band communication system was an analysis of the frequency lock loop of the Gunn oscillator used to generate the transmit frequency. The stability of the frequency lock loop was investigated and changes to the design were reviewed to alleviate the potential loss of data due the loop losing lock and entering the reacquisition mode. Other areas of investigation were the S-band antenna analysis and RF coverage analysis
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