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991.
J. A. Gallastegui C. L. Folcia J. Etxebarria J. Ortega I. De Francisco M. B. Ros 《Liquid crystals》2002,29(10):1329-1333
Optical second harmonic generation (SHG) measurements have been carried out on the B2 phases of three liquid crystal materials composed of conventional banana-shaped molecules (P-10-O-PIMB, P-8-O-PIMB and P-8-PIMB). Quantitative values of the second order susceptibilities dij have been deduced from SHG measurements at oblique incidences on polydomain racemic samples under an electric field. The dij coefficients are in the range 1-10 pm V-1. 相似文献
992.
David P. Kratz Martin G. Mlynczak Christopher J. Mertens Helen Brindley Larry L. Gordley Javier Martin-Torres Ferenc M. Miskolczi David D. Turner 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,90(3-4):323-341
A considerable fraction (>40%) of the outgoing longwave radiation escapes from the Earth's atmosphere-surface system within a region of the spectrum known as the far-infrared (wave-numbers less than 650 cm−1). Dominated by the line and continuum spectral features of the pure rotation band of water vapor, the far-infrared has a strong influence upon the radiative balance of the troposphere, and hence upon the climate of the Earth. Despite the importance of the far-infrared contribution, however, very few spectrally resolved observations have been made of the atmosphere for wave-numbers less than 650 cm−1. The National Aeronautics and Space Administration (NASA), under its Instrument Incubator Program (IIP), is currently developing technology that will enable routine, space-based spectral measurements of the far-infrared. As part of NASA's IIP, the Far-Infrared Spectroscopy of the Troposphere (FIRST) project is developing an instrument that will have the capability of measuring the spectrum over the range from 100 to 1000 cm−1 at a resolution of 0.6 cm−1. To properly analyze the data from the FIRST instrument, accurate radiative transfer models will be required. Unlike the mid-infrared, however, no inter-comparison of codes has been performed for the far-infrared. Thus, in parallel with the development of the FIRST instrument, an investigation has been undertaken to inter-compare radiative transfer models for potential use in the analysis of far-infrared measurements. The initial phase of this investigation has focused upon the inter-comparison of six distinct line-by-line models. The results from this study have demonstrated remarkably good agreement among the models, with differences being of order 0.5%, thereby providing a high measure of confidence in our ability to accurately compute spectral radiances in the far-infrared. 相似文献
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Asymptotic approximations are developed for zeros of the solutions Gi(z) and Hi(z) of the inhomogeneous Airy differential equation
. The solutions are also called Scorer functions. Tables are given with numerical values of the zeros. 相似文献
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Francisco Barahona 《Mathematical Programming》2006,105(2-3):181-200
We give an algorithm for the following problem: given a graph G=(V,E) with edge-weights and a nonnegative integer k, find a minimum cost set of edges that contains k disjoint spanning trees. This also solves the following reinforcement problem: given a network, a number k and a set of candidate edges, each of them with an associated cost, find a minimum cost set of candidate edges to be added
to the network so it contains k disjoint spanning trees. The number k is seen as a measure of the invulnerability of a network. Our algorithm has the same asymptotic complexity as |V| applications of the minimum cut algorithm of Goldberg & Tarjan.
Received: April, 2004 相似文献
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Francisco Javier TURIEL 《数学季刊》1995,(4)
TransverseDimensionofR ̄nActionsonCompactFoliatedManifolds¥FranciscoJavierTURIEL(GeometriaYTopologia,FacultaddeCienciasA.P.59;... 相似文献
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