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991.
In this contribution we propose a general framework for the construction of polyconvex energies for arbitrary anisotropy classes. The main idea is the introduction of an anisotropic metric reflecting the material symmetry of the underlying crystal. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
992.
We consider the initial-boundary value problem in a bounded domain with oscillatory moving boundaries and nonhomogeneous boundary conditions for the coupled system of equations of KdV type modelling strong interactions between internal solitary waves. We give a result of global existence and uniqueness for strong solutions for the coupled system of equations of Korteweg – de Vries type as well as the exponential decay of small solutions in asymptotically cylindrical domains. We present a numerical examples based in semi-implicit finite differences showing the numerical effect of the oscillatory moving boundaries for this kind of systems. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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994.
A nonlinear calculus of variations problem on time scales with variable endpoints is considered. The space of functions employed is that of piecewise rd-continuously Δ-differentiable functions (C1prd). For this problem, the Euler-Lagrange equation, the transversality condition, and the accessory problem are derived as necessary conditions for weak local optimality. Assuming the coercivity of the second variation, a corresponding second order sufficiency criterion is established. 相似文献
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Yulia H. Budnikova Vera V. Khrizanforova Ruzilya M. Galimullina Andrey A. Karasik Elvira I. Musina Aleksander R. Burilov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):84-90
Abstract Efficient catalytic systems mimicking the action of metalloenzymes based on cyclic frame structures containing phosphorus, nitrogen, and sulfur coordinating atoms for hydrogen oxidation or reduction under mild conditions are proposed. 相似文献
999.
The transformation of the ketone (1) to the unsaturated diester (11) a potential intermediate for the warburganal (12) is described. The Wittig reaction of theketone (1) with methylenetriphenylphosphorane afforded the olefin (2) which reacts with Woodward's reagent (MeCOOAg, I2 and MeCOOH and H2O) to give the diol (13). This on heating with dimethylsulfoxide afforded the tetralin (14) 相似文献
1000.
Vera Hemmelmayr Karl F. Doerner Richard F. Hartl Martin W.P. Savelsbergh 《European Journal of Operational Research》2010,202(3):7
We develop technology to plan delivery routes for the supply of blood products to hospitals by a blood bank. The technology produces low cost, robust plans that hedge against the natural uncertainty associated with blood product usage at hospitals. The technology relies on sampling-based approaches involving integer programming and variable neighborhood search. An extensive computational study shows the efficacy of the two approaches and highlights the impact of product usage uncertainty on the resulting delivery plans. 相似文献