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131.
132.
To establish the validity of the boundary-element method (BEM) for modeling scattering by swimbladder-bearing fish, the BEM is exercised in several ways. In a computation of backscattering by a 50-mm-diam spherical void in sea water at the four frequencies 38.1, 49.6, 68.4, and 120.4 kHz, agreement with the analytical solution is excellent. In computations of target strength as a function of tilt angle for each of 15 surface-adapted gadoids for which the swimbladders were earlier mapped, BEM results are in close agreement with Kirchhoff-approximation-model results at each of the same four frequencies. When averaged with respect to various tilt angle distributions and combined by regression analysis, the two models yield similar results. Comparisons with corresponding values derived from measured target strength functions of the same 15 gadoid specimens are fair, especially for the tilt angle distribution with the greatest standard deviation, namely 16 degrees. 相似文献
133.
Let ( G) be a flag-transitive c.c*-geometry whose point-stabilizer is not an affine group. We list all known examples and show that, if (, G) is a minimal unknown example, then G is an almost simple group and the commutator subgroup G is a simple group of Lie type. 相似文献
134.
Dr. Francis Buekenhout 《Mathematische Zeitschrift》1969,111(5):367-371
Sans résumé 相似文献
135.
Francis K. Fong 《Applied Physics A: Materials Science & Processing》1975,6(2):151-166
In this paper, the molecular details of the recently proposed energy upconversion theory of photosynthesis are reviewed. The primary light reactions are explained in terms of aC 2 symmetrical structure of the reaction center involving a (Chl?H2O)2 adduct. It is shown that exciton interaction within the (Chl?H2O)2 complex leads to an antisymmetric triplet state which may act as an energy trap. The presence of the energy trap in the reaction center suggests that the trigger step for the photoionization of active chlorophylls may involve the summation of two red excitation photons. Under normal conditions, the steadystate one-photon-per-electron quantum requirement is obtained. The functional properties of the various molecular constituents of the Chl-a molecule, such as the Ring V β-ketoester group, the phytyl tail, the central Mg atom, and the π-system of the macrocycle are explained within the present theoretical framework. A detailed analysis is given of the postulates and the consequences of the proposed model. The ramifications of the theory are probed, and their biological consequences are suggested for future study. 相似文献
136.
Claude Delmas Francis Menil Gilles Le Flem Claude Fouassier Paul Hagenmuller 《Journal of Physics and Chemistry of Solids》1978,39(1):51-53
A Mössbauer study of the dimensionality of magnetic interactions in the layer oxide LiCr0.99Fe0.01O2 shows a 2-D behaviour. 相似文献
137.
George K Francis 《Journal of Mathematical Analysis and Applications》1973,44(3):779-785
Certain nonlinear optimal control problems on a manifold can be represented in terms of a switchable family of regulated paths in the space of continuously differentiable vector fields. The methods also yield a theorem on the Dieudonné-Albrecht integrability conditions for non-autonomous first order differential equations on a Banach space. 相似文献
138.
Ralph Hugh Francis Denniston 《manuscripta mathematica》1973,8(1):21-26
A search has shown that any inversive plane of order 7 must be isomorphic with the Miquelian plane. The method used was explicitly set out in a companion paper, which was concerned with a plane of order 5. 相似文献
139.
140.