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141.
Edgar Reich 《Proceedings of the American Mathematical Society》1997,125(5):1479-1481
The possibility that the extremal dilatation of quasiconformal extensions from the circle is determined by quadrilaterals with vertices on the circle is related to an approximation question for holomorphic functions. This allows an alternative demonstration of a result of Anderson and Hinkkanen.
142.
Edgar Heilbronner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1995,107(22):2773-2774
143.
The compacted spin coefficient (ghp) formalism is clearly more concise and efficient than the older Newman-Penrose formalism. Yet few people use it when integration of the field equations is involved, Held being the notable exception. However, to most workers in the field, Held's approach seems far removed from the usual Newman-Unti (nu) type integration procedure. This paper and a subsequent one are concerned with integration within theghp formalism. In this first paper we develop aghp
coordinate-style integration procedure modelled closely on thenu procedure whereas in the second paper we present aghp
operator-style integration procedure along the lines suggested by Held. For simplicity of illustration we restrict the discussion to algebraically special vacuum spacetimes. We show clearly the similarities and differences between the two approaches, and compare their respective efficiencies. To deal with a concrete example, we illustrate the two methods by once more considering the problem of twisting typeN vacuum solutions to Einstein's field equations. TheGhp approach enables us to have a comprehensive overview of this much discussed problem and gain new insight into the relationship between various results derived in a number of different formalisms. 相似文献
144.
The unique extremality counterexample 总被引:4,自引:0,他引:4
Edgar Reich 《Journal d'Analyse Mathématique》1998,75(1):339-347
145.
Edgar Enochs 《Advances in Mathematics》2005,194(2):284-295
In this paper, we prove the existence of a flat cover and of a cotorsion envelope for any quasi-coherent sheaf over a scheme (X,OX). Indeed we prove something more general. We define what it is understood by the category of quasi-coherent R-modules, where R is a representation by rings of a quiver Q, and we prove the existence of a flat cover and a cotorsion envelope for quasi-coherent R-modules. Then we use the fact that the category of quasi-coherent sheaves on (X,OX) is equivalent to the category of quasi-coherent R-modules for some Q and R to get our result. 相似文献
146.
147.
Edgar Neuburger 《Bl?tter der DGVFM》1996,22(4):855-868
148.
The purpose of this study was to further develop and validate the Teaching Science as Inquiry (TSI) Instrument, an instrument designed to measure the self‐efficacy beliefs of preservice teachers in regards to the teaching of science as inquiry. Based on the validation processes and the associated data analysis, the TSI demonstrates continued content and construct validity with high internal reliability when used with prospective elementary science teachers. 相似文献
149.
G. Bieri F. Brogli E. Heilbronner Else Kloster-Jensen 《Journal of Electron Spectroscopy and Related Phenomena》1973,1(1):67-82
The photoelectron spectra (He I excitation) of trimethylsilylacetylene M(H) and of the four trimethylsilylhaloacetylenes M(X) with X = F, Cl, Br, I hav 相似文献
150.