14,231 research outputs found
Sprue cutoff tool for molded FCC plugs
Sprue removal operation is accomplished by positioning plug on tool bed, adjusting blades, and moving handle down for cutting process. Blades are raised to remove trimmed plug
C^+ distribution around S1 in rho Ophiuchi
We analyze a [C II] 158 micron map obtained with the L2 GREAT receiver on
SOFIA of the emission/reflection nebula illuminated by the early B star S1 in
the rho-OphA cloud core. This data set has been complemented with maps of
CO(3-2), 13CO(3-2) and C18O(3-2), observed as a part of the JCMT Gould Belt
Survey, with archival HCO^+(4-3) JCMT data, as well as with [O I] 63 and 145
micron imaging with Herschel/PACS. The [C II] emission is completely dominated
by the strong PDR emission from the nebula surrounding S1 expanding into the
dense Oph A molecular cloud west and south of S1. The [C II] emission is
significantly blue shifted relative to the CO spectra and also relative to the
systemic velocity, particularly in the northwestern part of the nebula. The [C
II] lines are broader towards the center of the S1 nebula and narrower towards
the PDR shell. The [C II] lines are strongly self-absorbed over an extended
region in the S1 PDR. Based on the strength of the [13C II] F = 2-1 hyperfine
component, [C II] is significantly optically thick over most of the nebula. CO
and 13CO(3-2) spectra are strongly self-absorbed, while C18O(3-2) is single
peaked and centered in the middle of the self-absorption. We have used a simple
two-layer LTE model to characterize the background and foreground cloud
contributing to the [C II] emission. From this analysis we estimate the
extinction due to the foreground cloud to be ~9.9 mag, which is slightly less
than the reddening estimated towards S1. Since some of the hot gas in the PDR
is not traced by low J CO emission, this result appears quite plausible. Using
a plane parallel PDR model with the observed [OI(145)]/[C II] brightness ratio
and an estimated FUV intensity of 3100-5000 G0 suggests that the density of the
[C II] emitting gas is ~3-4x10^3 cm^-3.Comment: Accepted for publication in Astronomy & Astrophysic
An integrated study of earth resources in the State of California based on Skylab and supporting aircraft data
There are no author-identified significant results in this report
Radar Scattering from Foamed Plastic Target Supports
This study investigates the scattering from foamed ranges to support all sizes of targets for radar cross section measurements. Two common foamed plastics, styrofoam and expanded bead polystyrene (EPS), are discussed. Two types of scattering are associated with foamed plastic, coherent and incoherent. The incoherent is normally the lowest, but has not been satisfactorily quantified. Coherent scattering is related to the shape of the target, and the emphasis of this study is on the coherent return. One goal was to predict the coherent RCS of an EPS column using the Uniform Theory of Diffraction (UTD). It was found that UTD can accurately predict the backscatter of an EPS column consisting of flat and curved surfaces. The second goal was to experimentally study the effects of shaping on coherent RCS. The benefits of adding a vertical slope to circular cylindrical columns was studied. RCS reductions of approximately 20 dB were achieved. Some low RCS column shapes were also measured; sloping did not produce a measurable RCS reduction in these cases
Optimal Moments for the Analysis of Peculiar Velocity Surveys II: Testing
Analyses of peculiar velocity surveys face several challenges, including low
signal--to--noise in individual velocity measurements and the presence of
small--scale, nonlinear flows. This is the second in a series of papers in
which we describe a new method of overcoming these problems by using data
compression as a filter with which to separate large--scale, linear flows from
small--scale noise that can bias results. We demonstrate the effectiveness of
our method using realistic catalogs of galaxy velocities drawn from N--body
simulations. Our tests show that a likelihood analysis of simulated catalogs
that uses all of the information contained in the peculiar velocities results
in a bias in the estimation of the power spectrum shape parameter and
amplitude , and that our method of analysis effectively removes this
bias. We expect that this new method will cause peculiar velocity surveys to
re--emerge as a useful tool to determine cosmological parameters.Comment: 28 pages, 9 figure
Folk and Other Tales from the Mother Lode, edited by Dewey Chambers
https://scholarlycommons.pacific.edu/dewey-chambers/1012/thumbnail.jp
Ukipau: Folk and Other Tales of the new Hawaiians, edited by
https://scholarlycommons.pacific.edu/dewey-chambers/1014/thumbnail.jp
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