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111.
Wilfried Imrich Iztok Peterin Simon Špacapan Cun‐Quan Zhang 《Journal of Graph Theory》2010,64(4):267-276
We prove that the strong product G1? G2 of G1 and G2 is ?3‐flow contractible if and only if G1? G2 is not T? K2, where T is a tree (we call T? K2 a K4‐tree). It follows that G1? G2 admits an NZ 3 ‐flow unless G1? G2 is a K4 ‐tree. We also give a constructive proof that yields a polynomial algorithm whose output is an NZ 3‐flow if G1? G2 is not a K4 ‐tree, and an NZ 4‐flow otherwise. © 2009 Wiley Periodicals, Inc. J Graph Theory 64: 267–276, 2010 相似文献
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Henri de Maissin Philipp R. Groß Obaid Mohiuddin Dr. Moritz Weigt Luca Nagel Marvin Herzog Zirun Wang Robert Willing Dr. Wilfried Reichardt Dr. Martin Pichotka Dr. Lisa Heß Prof. Dr. Thomas Reinheckel Prof. Dr. Henning J. Jessen Prof. Dr. Robert Zeiser Prof. Dr. Michael Bock Prof. Dominik von Elverfeldt Prof. Dr. Maxim Zaitsev Dr. Sergey Korchak Dr. Stefan Glöggler Prof. Dr. Jan-Bernd Hövener Prof. Dr. Eduard Y. Chekmenev Prof. Dr. Franz Schilling Dr. Stephan Knecht Dr. Andreas B. Schmidt 《Angewandte Chemie (International ed. in English)》2023,62(36):e202306654
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The present paper considers the effect of electromechanical coupling on the interlaminar stresses and the electric field strengths at free edges of laminated plates with piezoelectric material properties. The results of coupled and uncoupled piezoelectric analyses performed by use of the finite element method are compared. Exemplarily, a symmetric cross‐ply and a symmetric angle‐ply laminate are investigated under uniaxial tension and without any electrical loading. It is shown that the interlaminar stresses at the free edge are significantly higher in the coupled case for the symmetric cross‐ply laminate, whereas the coupling effect for the symmetric angle‐ply laminate is of minor significance. In addition, the occurrence of electric field strengths with singular character is revealed. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
117.
A heuristic algorithm for the weight minimization of sandwich structures by a specific kind of topology optimization is presented. The method employs a preexisting algorithm for the layerwise topology optimization of symmetric laminates under in‐plane loads and expands this method for the case of bending. During the optimization procedure the algorithm adds or subtracts material from the layers of the face sheets and the core of the sandwich plate in regions of high or low stresses respectively. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Wilfried Wurth 《Physik in unserer Zeit》1999,30(1):41-41
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The cosmological baryon asymmetry can be explained as remnant of heavy Majorana neutrino decays in the early universe. We study this mechanism for two models of neutrino masses with a large νμ−ντ mixing angle which are based on the symmetries SU(5)×U(1)F and SU(3)c×SU(3)L×SU(3)R×U(1)F, respectively. In both cases B−L is broken at the unification scale ΛGUT. The models make different predictions for the baryogenesis temperature and the gravitino abundance. 相似文献
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Stress fields in the vicinity of free edges and corners of composite laminates exhibit singular characteristics and may lead to premature interlaminar failure modes like delamination fracture. It is of practical interest to investigate the nature of the arising free-edge and free-corner stress singularities - i.e. the singularity orders and modes - closely. The present investigations are performed using the Boundary Finite Element Method (BFEM) which in essence is a fundamental-solution-less boundary element method employing standard finite element formulations. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献