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771.
In this paper we consider Neumann noncoercive hemivariational inequalities, focusing on nontrivial solutions. We use the critical point theory for locally Lipschitz functionals. 相似文献
772.
We show that Bloch oscillations are possible in dissipative optical waveguide lattices with a linearly varying propagation constant. These oscillations occur in spite of the fact that the Bloch wave packet experiences coupling gain and (or) loss. Experimentally, this process can be observed in different settings, such as in laser arrays and lattices of semiconductor optical amplifiers. In addition, we demonstrate that these systems can suppress instabilities arising from preferential mode noise growth. 相似文献
773.
Sophia Th. Kyritsi Nikolaos S. Papageorgiou 《Proceedings of the American Mathematical Society》2005,133(8):2369-2376
We examine a nonlinear strongly resonant elliptic problem driven by the -Laplacian and with a discontinuous nonlinearity. We assume that the discontinuity points are countable and at them the nonlinearity has an upward jump discontinuity. We show that the problem has at least two nontrivial solutions without using a multivalued interpretation of the problem as it is often the case in the literature. Our approach is variational based on the nonsmooth critical point theory for locally Lipschitz functions.
774.
We study the production of W bosons at large transverse momentum in pp collisions at the CERN Large Hadron Collider. We calculate the complete next-to-leading order (NLO) corrections to the differential cross section. We find that the NLO corrections provide a large increase to the cross section but, surprisingly, do not reduce the scale dependence relative to leading order (LO). We also calculate next-to-next-to-leading-order (NNLO) soft-gluon corrections and find that, although they are small, they significantly reduce the scale dependence thus providing a more stable result. 相似文献
775.
Skaropoulos NC Chrissoulidis DP 《The Journal of the Acoustical Society of America》2003,114(2):726-736
The method of small perturbations is applied to the problem of plane-wave scattering from a soft circular surface with sinusoidal roughness. Rayleigh-theory and extinction-theorem perturbative solutions of arbitrary order are developed, and they are compared to each other as well as to an exact solution. A numerical study yields quantitative information about effects associated with the use of the Rayleigh hypothesis, about the merit of higher-order solutions, and about the reliability of the error criteria that measure a posteriori the conformity of perturbative solutions to the boundary condition. It is shown that the accuracy of perturbative solutions depends not only on the height, but also on the slope, of surface corrugations. Moreover, it is shown that the Rayleigh hypothesis does not affect the accuracy of far-field perturbative calculations. The mean extinction error is proposed as a measure for the error of the extinction-theorem perturbative solution. 相似文献
776.
Efremidis NK Hudock J Christodoulides DN Fleischer JW Cohen O Segev M 《Physical review letters》2003,91(21):213906
We study various families of two-dimensional discrete or lattice solitons, and show that they are possible only when their power level exceeds a critical threshold. In addition, we show that gap-lattice solitons exist only when the lattice possesses a complete 2D band gap. Our results suggest that these conditions are universally valid, irrespective of the nature of the nonlinearity or the specific structure of the index lattice. The analysis explains fundamental aspects of behavior of two-dimensional discrete solitons that have been very recently observed in photosensitive optical crystals. 相似文献
777.
Nikolaos C. Kourogenis 《Journal of Mathematical Analysis and Applications》2003,287(2):348-364
In this paper, we study second order differential inclusions in with a maximal monotone term and generalized boundary conditions. The nonlinear differential operator need not be necessary homogeneous and incorporates as a special case the one-dimensional p-Laplacian. The generalized boundary conditions incorporate as special cases well-known problems such as the Dirichlet (Picard), Neumann and periodic problems. As application to the proven results we obtain existence theorems for both “convex” and “nonconvex” problems when the maximal monotone term A is defined everywhere and when not (case of variational inequalities). 相似文献
778.
Nikolaos Klouras 《Monatshefte für Chemie / Chemical Monthly》1991,122(6-7):533-536
Summary Reaction of the titanocene complexes (RC5H4)2Ti(SH)2, [R = CH3, Si(CH3)3] with elemental selenium in refluxing carbon disulfide leads to H2S evolution and to selective formation of the titanocene sulfidotetraselenides (RC5H4)2TiSSe4. In these compounds the SSe4 chain acts as a bidentate chelating ligand. 相似文献
779.
Nikolaos Halidias 《Bulletin des Sciences Mathématiques》2003,127(6):549-556
We consider a class of noncoercive hemivariational inequalities involving the p-Laplacian. Our goal is to obtain the existence of a nontrivial solution. Using the mountain-pass theorem for locally Lipschitz functionals we obtain the desired result. 相似文献
780.