60,817 research outputs found
Self-Evaluation of Black and White College Students
A major issue in the social psychology of race relations has been the axiom that blacks tend to manifest lower self-esteem than whites.[1] Much of the empirical support for this hypothesis came from studies demonstrating that blacks are stigmatized and subjected to a variety of unpleasant and derogatory experiences.[2] However, these studies are limited in two respects: first, by their use of small, nonrepresentative samples (primarily nursery school and kindergarten children) and second, by their reliance upon inferential (semi-projective) measures of self-esteem.[3
Avalanche-diode oscillator circuit with tuning at multiple frequencies Quarterly technical report, 4 Mar. - 4 Jun. 1970
Computer programs for calculating operating characteristics of avalanche diode oscillator
Study to define low voltage and low temperature operating limits of the Pioneer 10/11 Meteoroid Detection Equipment (MDE) system
The Pioneer 10/11 meteoroid detection equipment (MDE) pressure cells were tested at liquid nitrogen (LN2) and liquid helium (LHe) temperatures with the excitation voltage controlled as a parameter. The cells failed by firing because of pressurizing gas condensation as the temperature was lowered from LN2 to LHe temperature and when raised from LHe temperature. A study was conducted to determine cell pressure as a function of temperature, and cell failure was estimated as a function of temperature and excitation voltage. The electronic system was also studied, and a profile of primary spacecraft voltage (nominally 28 Vdc) and temperature corresponding to electronic system failure was determined experimentally
A feasibility study of a miniature solid-state pressure transducer
Potential electrical response of p-n junction to mechanical strai
Low density bismaleimide-carbon microballoon composites
A process is described for the preparation of composite laminate.structures of glass cloth preimpregnated with polybismaleimide resin and adhered to a polybismaleimide glass or aromatic polyamide paper honeycomb cell structure that is filled or partially filled with a syntactic foam consisting of a mixture of bismaleimide resin and carbon microballoons. The carbon microballoons are prepared by pyrolyzing phenolic microballoons and subsequently bonded using a 2% bismaleimide solution. The laminate structures are cured for two hours at 477 deg K and are adhered to the honeycomb bismaleimide adhesive using a pressure of 700 KN/sq m pressure at 450 deg K. The laminate composite is then post-cured for two hours at 527 deg K to produce a composite laminate having a density in the range from about 95 kilograms per cubic meter to 130 kilograms per cubic meter
Scaling Relations in the Vortex State of Nodal Superconductors
In contrast to multigap superconductors (e.g. MgB), the low-temperature
properties of nodal superconductors are dominated by nodal excitations. Here we
extend for a variety of nodal superocnductors the earlier work by Simon and Lee
and K\"ubert and Hirschfeld. The scaling relations seen in the thermodynamics
and the thermal conductivity will provide an unequivocal test of nodal
superconductivity.Comment: 9 pages, 3 figure
Inflation, Renormalization, and CMB Anisotropies
In single-field, slow-roll inflationary models, scalar and tensorial
(Gaussian) perturbations are both characterized by a zero mean and a non-zero
variance. In position space, the corresponding variance of those fields
diverges in the ultraviolet. The requirement of a finite variance in position
space forces its regularization via quantum field renormalization in an
expanding universe. This has an important impact on the predicted scalar and
tensorial power spectra for wavelengths that today are at observable scales. In
particular, we find a non-trivial change in the consistency condition that
relates the tensor-to-scalar ratio "r" to the spectral indices. For instance,
an exact scale-invariant tensorial power spectrum, n_t=0, is now compatible
with a non-zero ratio r= 0.12 +/- 0.06, which is forbidden by the standard
prediction (r=-8n_t). Forthcoming observations of the influence of relic
gravitational waves on the CMB will offer a non-trivial test of the new
predictions.Comment: 4 pages, jpconf.cls, to appear in the Proceedings of Spanish
Relativity Meeting 2009 (ERE 09), Bilbao (Spain
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