23,661 research outputs found
Correlation of low speed wind tunnel and flight test data for V/STOL aircraft
The XV-5B fan-in-wing aircraft and the Y0V-10 RCF rotating cylinder flap aircraft were subjected to wind tunnel tests. These tests were conducted specifically to provide for correlation between wind tunnel and inflight aerodynamics and noise test data. Correlation between aerodynamic and noise data are presented and testing techniques that are related to the accuracy of the data, or that might affect the correlations, are discussed
Correlation of wind-tunnel and flight-test aerodynamic data for five V/STOL aircraft
Correlation of wind tunnel and flight test aerodynamic data for five V/STOL aircraf
Using rewards and penalties to obtain desired subject performance
Operant conditioning procedures, specifically the use of negative reinforcement, in achieving stable learning behavior is described. The critical tracking test (CTT) a method of detecting human operator impairment was tested. A pass level is set for each subject, based on that subject's asymptotic skill level while sober. It is critical that complete training take place before the individualized pass level is set in order that the impairment can be detected. The results provide a more general basis for the application of reward/penalty structures in manual control research
W. H. Cook to Unknown (25 March 1862)
Rumors of advancements and retreats, his current location, the company\u27s health, mail route problems and supplieshttps://egrove.olemiss.edu/ciwar_corresp/1573/thumbnail.jp
Quasi-circular Orbits for Spinning Binary Black Holes
Using an effective potential method we examine binary black holes where the
individual holes carry spin. We trace out sequences of quasi-circular orbits
and locate the innermost stable circular orbit as a function of spin. At large
separations, the sequences of quasi-circular orbits match well with
post-Newtonian expansions, although a clear signature of the simplifying
assumption of conformal flatness is seen. The position of the ISCO is found to
be strongly dependent on the magnitude of the spin on each black hole. At close
separations of the holes, the effective potential method breaks down. In all
cases where an ISCO could be determined, we found that an apparent horizon
encompassing both holes forms for separations well inside the ISCO.
Nevertheless, we argue that the formation of a common horizon is still
associated with the breakdown of the effective potential method.Comment: 13 pages, 10 figures, submitted to PR
Translanguaging identities: creating transnational space through flexible multilingual practices amongst Chinese university students in the UK
There are thousands of ethnic Chinese students from very different backgrounds in British universities today, a fact that has not been fully appreciated or studied from an applied linguistics perspective. For example, there are third- or fourth-generation British-born Chinese; there are students from China, Taiwan, Hong Kong and Singapore who have received whole or part of their primary and secondary education in Britain; and there are Chinese students who completed their schooling in their home countries. To add to the diversity of the Chinese student population, several distinctive varieties of Chinese are spoken as well as different varieties of English and other languages. In terms of their choice of language and social networks, the Chinese students have several options, including, for example, staying with their own language variety group (e.g. Cantonese, Mandarin); staying with their own region-of-origin group (e.g. British-born, Mainland Chinese, Taiwanese, Hong Kong); and creating new transnational and multilingual groupings. This article focuses on a group of Chinese university students who have chosen to create transnational and multilingual networks. Through analysis of narrative data and ethnographic observations, we explore issues such as their socio-cultural identification processes, the interactions between their linguistic and political ideologies; their multilingual practices and what they have learned from being part of this new social space
Relativistic stars in differential rotation: bounds on the dragging rate and on the rotational energy
For general relativistic equilibrium stellar models (stationary axisymmetric
asymptotically flat and convection-free) with differential rotation, it is
shown that for a wide class of rotation laws the distribution of angular
velocity of the fluid has a sign, say "positive", and then both the dragging
rate and the angular momentum density are positive. In addition, the "mean
value" (with respect to an intrinsic density) of the dragging rate is shown to
be less than the mean value of the fluid angular velocity (in full general,
without having to restrict the rotation law, nor the uniformity in sign of the
fluid angular velocity); this inequality yields the positivity and an upper
bound of the total rotational energy.Comment: 23 pages, no figures, LaTeX. Submitted to J. Math. Phy
Black Hole Data via a Kerr-Schild Approach
We present a new approach for setting initial Cauchy data for multiple black
hole spacetimes. The method is based upon adopting an initially Kerr-Schild
form of the metric. In the case of non-spinning holes, the constraint equations
take a simple hierarchical form which is amenable to direct numerical
integration. The feasibility of this approach is demonstrated by solving
analytically the problem of initial data in a perturbed Schwarzschild geometry.Comment: 13 pages, RevTeX forma
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