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151.
The dependence of the linear stability of two-time-level finite-difference semi-implicit schemes on the choice of reference temperature profile is studied. Particular vertical profiles of the temperature are considered to derive analytical conditions of stability. Analysis is made for general form of different model parameters such as the number of vertical levels and their distribution, the time step size, and the values of the viscosity coefficients. The derived conditions of stability are more restrictive than those for three-time-level schemes, but obtained necessary and sufficient condition for constant vertical lapse rates of the temperature has the form frequently applied to three-time-level schemes: the basic temperature profile should be warmer than the actual one. Performed numerical experiments show that the last restriction is neither necessary nor sufficient condition of stability for general temperature profiles. 相似文献
152.
Véronique Dupuis Nils Blanc Luis E. Diaz-Sanchez Arnaud Hillion Alexandre Tamion Florent Tournus Gustavo M. Pastor Andrei Rogalev Fabrice Wilhelm 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2013,67(2):1-4
In this paper, the one-way absorption property in one-dimensional dielectric/metal photonic crystal structure with a dielectric defect layer is studied. The effects of incident angle and state of polarization on one-way absorption behaviour of the anti-resonant (AR) mode are investigated. The normally incident wave from left to right propagation is totally allowed to penetrate to the structure but right to left propagation totally reflected at the same wavelength. It is found that, with increasing of the incident angle, the AR mode shifts to the lower wavelengths and its intensity decreases. Simultaneously, another AR mode with reversed one-way property appears at higher wavelength. The one-way behaviour on absorption is observed at the both states of polarizations but is localized on different wavelengths. Those effects, are suggesting that the proposed structure can be used as a direction sense polarization splitter or reflector/antireflector device. 相似文献
153.
154.
Andrei Yu. Khrennikov Marcus Nilsson 《Proceedings of the Steklov Institute of Mathematics》2009,265(1):140-142
We discuss the similarity of the degeneration structure of the genetic code with a purely number theoretic “divisors code.”
The most interesting thing about our observation is not that there is a connection between number theory and the genetic code,
but the simplicity of the rule. We hope that the observation and the naive model presented in this paper will spur ideas for
other models of the degeneracy of the genetic code. Maybe, the ideas of this article can also be used in the area of artificial
life to synthesize artificial genetic codes. 相似文献
155.
We find a set of generators and relations for the system of extended tautological rings associated to the moduli spaces of stable maps in genus zero, admitting a simple geometrical interpretation. In particular, when the target is Pn, these give a complete presentation for the cohomology and Chow rings in the cases with/without marked points. 相似文献
156.
157.
We give a uniform geometric realization for the cluster algebra of an arbitrary finite type with principal coefficients at an arbitrary acyclic seed. This algebra is realized as the coordinate ring of a certain reduced double Bruhat cell in the simply connected semisimple algebraic group of the same Cartan–Killing type. In this realization, the cluster variables appear as certain (generalized) principal minors. 相似文献
158.
159.
Rita Giuliano Antonini Yuriy Kozachenko Andrei Volodin 《Journal of Mathematical Analysis and Applications》2008,338(2):1188-1203
The almost sure convergence of weighted sums of φ-subgaussian m-acceptable random variables is investigated. As corollaries, the main results are applied to the case of negatively dependent and m-dependent subgaussian random variables. Finally, an application to random Fourier series is presented. 相似文献
160.