13,444 research outputs found
An experiment to show the comparative values of teaching by the lecture, question and answer, and socialized methods
Not available.Avery D. GabbardNot ListedNot ListedMaster of ScienceDepartment Not ListedCunningham Memorial Library, Terre Haute, Indiana State University.isua-thesis-1950-gabbard_aMastersTitle from document title page. Document formatted into pages: contains 77p. : ill. Includes appendix and bibliography
Performance of a Haynes 188 metallic standoff thermal protection system at Mach 7
A flight weight, metallic thermal protection system (TPS) model applicable to reentry and hypersonic vehicles was subjected to multiple cycles of both radiant and aerothermal heating to evaluate its aerothermal performance and structural integrity. The TPS was designed for a maximum operating temperature of 1255 K and featured a shingled, corrugation stiffened corrugated skin heat shield of Haynes 188, a cobalt base alloy. The model was subjected to 3 radiant preheat/aerothermal tests for a total of 67 seconds and to 15 radiant heating tests for a total of 85.9 minutes at 1255 K. The TPS limited the primary structure to temperatures below 430 K in all tests. No catastrophic failures occurred in the heat shields, supports, or insulation system. The TPS continued to function even after exposure to a differential temperature 4 times the design value produced thermal buckles in the outer skin. The shingled thermal expansion joint effectively allowed for thermal expansion of the heat shield without allowing any appreciable hot gas flow into the model cavity, even though the overlap gap between shields increased after several thermal cycles
Techniques for studying gravity waves and turbulence: Horizontal, vertical and temporal resolution needed
One of the most important atmospheric measurements that is needed is a measure of the gravity-wave spectrum. The MST radar has been investigated as means to measure the temporal resolution required to determine gravity-wave oscillations. The required vertical and horizontal resolution is dependent on the particular part of the gravity wave spectrum that is analyzed. Horizontal spacing is also discussed
Firewalls in AdS/CFT
Several recent papers argue against firewalls by relaxing the requirement for
locality outside the stretched horizon. In the firewall argument, locality
essentially serves the purpose of ensuring that the degrees of freedom required
for infall are those in the proximity of the black hole and not the ones in the
early radiation. We make the firewall argument sharper by utilizing the AdS/CFT
framework and claim that the firewall argument essentially states that the dual
to a thermal state in the CFT is a firewall.Comment: 11 pages plus references, 8 figures; version accepted for publication
in JHE
Interpolation problems in meteor radar analysis, part 7.6A
Meteor echoes come from random points in the observation volume, and are irregularly spaced in time. This precludes the use of fast fourier transformations (FFT) techniques on the raw data to give the spectrum of waves that are present. One way around this obstacle is to restrict our interest to a particular class of waves, and fit a corresponding model to the raw data. It is assumed that there is no horizontal variation across the observation volume for tides, but in the vertical this is certainly not the case. If, in addition, we are interested in other types of waves which may be present and whose periods are unknown, then examining the raw line-of-sight velocities does not tell us how to modify the model, since the line-of-sight direction is not fixed. This is the motivation for interpolation. Interpolation takes a temporal series of line-of-sight velocities, and transforms it to a temporal series of wind velocities for each orthogonal direction. The velocities along a given direction can then be examined readily for any waves in addition to tides
Large Area Crop Inventory Experiment (LACIE). Level 3 baseline; LACIE commodity data control plan for JSC
There are no author-identified significant results in this report
Unitarity and fuzzball complementarity: "Alice fuzzes but may not even know it!"
We investigate the recent black hole firewall argument. For a black hole in a
typical state we argue that unitarity requires every quantum of radiation
leaving the black hole to carry information about the initial state. An
information-free horizon is thus inconsistent with unitary at every step of the
evaporation process (in particular both before and after Page time). The
required horizon-scale structure is manifest in the fuzzball proposal which
provides a mechanism for holding up the structure. In this context we want to
address the experience of an infalling observer and discuss the recent fuzzball
complementarity proposal. Unlike black hole complementarity and observer
complementarity which postulate asymptotic observers experience a hot membrane
while infalling ones pass freely through the horizon, fuzzball complementarity
postulates that fine-grained operators experience the details of the fuzzball
microstate and coarse-grained operators experience the black hole. In
particular, this implies that an infalling detector tuned to energy E ~ T,
where T is the asymptotic Hawking temperature, does not experience free infall
while one tuned to E >> T does.Comment: v3: 33 pages + citations, 8 figures, version accepted for publicatio
Notes on the systematics of micromammals from Sterkfontein, Gauteng, South Africa
The micromammalian fauna from Sterkfontein Members 4 , 5E and 6 comprises 34 species. These include six insectivores, three bats, three elephant shrews and 22 rodents. Most of these taxa, or their equivalents, have been previously recorded. Four or five new additions were recovered from deposits probably belonging to Late Pleistocene Member 6, which have previously received little or no attention. Some previously recorded taxa were not found, but this was probably due to differences in identification rather than to the absence of these forms from the sample.THE COUNCIL’S RESEARCH COMMITTEE, UNIVERSITY OF THE WITWATERSRAND; NATIONAL RESEARCH FOUNDATION (NRF
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