39,318 research outputs found
Impact simulator Patent
Lunar and planetary gravity simulator to test vehicular response to landin
Flexible ring slosh damping baffle Patent
Flexible ring slosh damping baffle for spacecraft fuel tan
Evaluation of turbulent dissipation rate retrievals from Doppler Cloud Radar
Turbulent dissipation rate retrievals from cloud radar Doppler velocity measurements are evaluated using independent, in situ observations in Arctic stratocumulus clouds. In situ validation data sets of dissipation rate are derived using sonic anemometer measurements from a tethered balloon and high frequency pressure variation observations from a research aircraft, both flown in proximity to stationary, ground-based radars. Modest biases are found among the data sets in particularly low- or high-turbulence regimes, but in general the radar-retrieved values correspond well with the in situ measurements. Root mean square differences are typically a factor of 4-6 relative to any given magnitude of dissipation rate. These differences are no larger than those found when comparing dissipation rates computed from tetheredballoon and meteorological tower-mounted sonic anemometer measurements made at spatial distances of a few hundred meters. Temporal lag analyses suggest that approximately half of the observed differences are due to spatial sampling considerations, such that the anticipated radar-based retrieval uncertainty is on the order of a factor of 2-3. Moreover, radar retrievals are clearly able to capture the vertical dissipation rate structure observed by the in situ sensors, while offering substantially more information on the time variability of turbulence profiles. Together these evaluations indicate that radar-based retrievals can, at a minimum, be used to determine the vertical structure of turbulence in Arctic stratocumulus clouds
Lunar penetrometer Patent
Development and characteristics of pentrometer for measuring physical properties of lunar surfac
The Underrepresentation of Minority Faculty in Higher Education: Panel Discussion
[Excerpt] The 3 July 2002 issue of the Chronicle of Higher Education described the matter we are discussing today in these words: Taken together. African-Americans and persons of Hispanic origin represent only 8 percent of full-time faculty nation-wide, and while 5 percent are African-American, half of them work at historically black institutions. The proportion of black faculty members at white institutions is 2.3 percent, virtually the same as it was 20 years ago.
We are privileged to have the opportunity to explore this issue from two different perspectives. The first contends that unless major changes occur, the number of minority students interested in and prepared for faculty positions will remain dreadfully insufficient and that, furthermore, affirmative action has been a culprit in this process and leads many of these students into higher educational environments in which they do not perform well enough to even seriously consider or be considered for careers in academe. The other position says that, although the supply of minority faculty candidates is admittedly small, the relatively low level of commitment from higher educational institutions to recruit, hire, and promote minority candidates and the salary disparity between academe and industry lead to a problem of demand that must be appreciated and addressed. Furthermore, it argues, affirmative action has been beneficial in increasing minority faculty presence
Applicability of satellite remote sensing for detection and monitoring of coal strip mining activities
The author has identified the following significant results. Large areas covered by orbital photography allows the user to estimate the acreage of strip mining activity from a few frames. Infrared photography both in color and in black and white transparencies was found to be the best suited for this purpose
The Physics Inside Topological Quantum Field Theories
We show that the equations of motion defined over a specific field space are
realizable as operator conditions in the physical sector of a generalized Floer
theory defined over that field space. The ghosts associated with such a
construction are found not to be dynamical. This construction is applied to
gravity on a four dimensional manifold, ; whereupon, we obtain Einstein's
equations via surgery, along , in a five-dimensional topological quantum
field theory.Comment: LaTeX, 7 page
Stranded superconducting cable of improved design
High-current cable developed in liquid helium cooled magnets uses aluminum wire interspersed with the superconductor strands. The aluminum maintains higher electrical conductivity, is light in weight, and has low thermal capacity
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