146,828 research outputs found
Mesoscale ageostrophic circulations associated with baroclinic jet streaks
Studies of ageostrophic motion attending jet streaks and convection are examined. Various types of dynamical experiments are carried out with the hybrid isentropic-sigma coordinate model. The effects of vorticity and static stability distributions on the intensity of secondary circulations forced by inertial accelerations as well as the superposition of an amplifying baroclinic wave on the jet streak structure are investigated
Theory and Simulations of Refractive Substructure in Resolved Scatter-Broadened Images
At radio wavelengths, scattering in the interstellar medium distorts the
appearance of astronomical sources. Averaged over a scattering ensemble, the
result is a blurred image of the source. However, Narayan & Goodman (1989) and
Goodman & Narayan (1989) showed that for an incomplete average, scattering
introduces refractive substructure in the image of a point source that is both
persistent and wideband. We show that this substructure is quenched but not
smoothed by an extended source. As a result, when the scatter-broadening is
comparable to or exceeds the unscattered source size, the scattering can
introduce spurious compact features into images. In addition, we derive
efficient strategies to numerically compute realistic scattered images, and we
present characteristic examples from simulations. Our results show that
refractive substructure is an important consideration for ongoing missions at
the highest angular resolutions, and we discuss specific implications for
RadioAstron and the Event Horizon Telescope.Comment: Equation numbering in appendix now matches published version. Two
minor typos correcte
Gas lubricant compositions Patent
High temperature gas lubricant consisting of two fluoro-bromo-methane
Filled polymers for bearings and seals used in liquid hydrogen
Filled polytrifluorochloroethylene /PTFCE/ shows better thermal stability, less creep, and higher compressive moduli than filled polytetrafluoroethylene /PTFE/. Bearing and seal materials exhibiting the best characteristics contain a high percentage of PTFCE
Heart Rate Patterns Observed in Medical Monitoring
Medical monitoring of heart rate patterns during conditions of sleep, quiet rest, breath-holding, hypoxia, and increased g forces of aircraft fligh
Metallic film diffusion for boundary lubrication Patent
Metallic film diffusion for boundary lubrication in aerospace engineerin
-pairing Interactions of Fermions in a Single- Shell
In this talk I shall introduce our recent works on general pairing
interactions and pair truncation approximations for fermions in a single-j
shell, including the spin zero dominance, features of eigenvalues of fermion
systems in a single-j shell interacting by a pairing interaction.Comment: 10 pages and 4 figures, international symposiu
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