76,906 research outputs found

    Self-Evaluation of Black and White College Students

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    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

    A feasibility study of a miniature solid-state pressure transducer

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    Potential electrical response of p-n junction to mechanical strai

    Study to define low voltage and low temperature operating limits of the Pioneer 10/11 Meteoroid Detection Equipment (MDE) system

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    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

    Inflation, Renormalization, and CMB Anisotropies

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    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

    Under the hood: How an authentic online course was designed, delivered and evaluated

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    A key challenge for university professionals is to identify how to construct more interactive, engaging and student-centred environments that promote 21st century skills and encourage selfdirected learning. Existing research suggests the use of real-life tasks supported by new technologies, together with access to the vast array of open educational resources on the Internet, have the potential to improve the quality of online learning. This paper describes how an authentic online professional development course for higher education practitioners was designed and implemented using a learning management system (LMS) and an open companion website. It also briefly discusses how the initial iteration was evaluated and identifies recommendations for improving future iterations of the cours

    New Structure In The Shapley Supercluster

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    We present new radial velocities for 189 galaxies in a 91 sq. deg region of the Shapley supercluster measured with the FLAIR-II spectrograph on the UK Schmidt Telescope. The data reveal two sheets of galaxies linking the major concentrations of the supercluster. The supercluster is not flattened in Declination as was suggested previously and it may be at least 30 percent larger than previously thought with a correspondingly larger contribution to the motion of the Local Group.Comment: LaTex: 2 pages, 1 figure, includes conf_iap.sty style file. To appear in proceedings of The 14th IAP Colloquium: Wide Field Surveys in Cosmology, held in Paris, 1998 May 26--30, eds. S.Colombi, Y.Mellie
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