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31.
P. B. Sarkar N. R. Dhar J. M. Kalthoff J. Holluta J. Obrist G. Krüss J. Nicklès A. Skrabal J. Preiss O. T. Christensen M. Geloso P. Dubois F. P. Treadwell R. W. Coltman A. Gorgeu O. Hauser F. Wirth und O. Hackl 《Fresenius' Journal of Analytical Chemistry》1930,80(5-6):216-228
Ohne Zusammenfassung 相似文献
32.
F. Wirth V. Lenher C. C. Meloche E. J. Roberts F. J. Metzger Ph. E. Browning H. E. Palmer C. James und L. A. Pratt 《Fresenius' Journal of Analytical Chemistry》1919,58(8):358-361
Ohne Zusammenfassung 相似文献
33.
P. N. Kogerman G. Egloff J. C. Morrell Ch. Wirth III G. B. Murphy 《Analytical and bioanalytical chemistry》1935,100(5-6):238-238
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35.
Jesus Lerma Tariq Khraishi Yu-Lin Shen Brian D. Wirth 《Mechanics Research Communications》2003,30(4):325-334
Analytical solutions for the displacement and stress fields due to a misfit particle in a host matrix can be difficult to obtain, especially for complex particle geometries. In this work, we present a numerical method for finding such fields in the case of infinitely-long particles. The method is based on discretizing the continuous misfit region between the particle and matrix into local misfit regions consisting of interstitial dislocation loops. The results presented here indicate very good agreement with analytical solutions and better convergence with increasing loop density. 相似文献
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37.
Michael Ruzhansky Ville Turunen Jens Wirth 《Journal of Fourier Analysis and Applications》2014,20(3):476-499
In this paper we give several global characterisations of the Hörmander class \(\Psi ^m(G)\) of pseudo-differential operators on compact Lie groups in terms of the representation theory of the group. The result is applied to give criteria for the ellipticity and the global hypoellipticity of pseudo-differential operators in terms of their matrix-valued full symbols. Several examples of the first and second order globally hypoelliptic differential operators are given, in particular of operators that are locally not invertible nor hypoelliptic but globally are. Where the global hypoelliptiticy fails, one can construct explicit examples based on the analysis of the global symbols. 相似文献
38.
We examine a network upgrade problem for cost flows. A budget can be distributed among the arcs of the network. An investment on each single arc can be used either to decrease the arc flow cost, or to increase the arc capacity, or both. The goal is to maximize the flow through the network while not exceeding bounds on the budget and on the total flow cost.
The problems are NP-hard even on series-parallel graphs. We provide an approximation algorithm on series-parallel graphs which, for arbitrary δ,>0, produces a solution which exceeds the bounds on the budget and the flow cost by factors of at most 1+δ and 1+, respectively, while the amount of flow is at least that of an optimum solution. The running time of the algorithm is polynomial in the input size and 1/(δ). In addition we give an approximation algorithm on general graphs applicable to problem instances with small arc capacities. 相似文献
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Cyclization cascades involving C-C bond formations followed by lactonization reactions provide fast access to structurally complex tricyclic indane and tetrahydronaphthalene derivatives. 相似文献