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Ivan Pan 《Comptes Rendus Mathematique》2005,341(7):439-443
We show that the first dynamical degree of a Cremona transformation stabilizing an irrational non elliptic curve is 1. Moreover, among these transformations, we characterize those which have finite order. To cite this article: I. Pan, C. R. Acad. Sci. Paris, Ser. I 341 (2005). 相似文献
4.
V. G. Lapin 《Radiophysics and Quantum Electronics》1995,38(3-4):195-198
It is shown that the nonstable character of nonlinear interaction of a system of waves similar to that resulting from double stimulated Brillouin scattering is retained upon the oblique incidence of a powerful electromagnetic wave on a layer of supercritical plasma. In this case we have nonlinear back reflection from a layer of supercritical plasma. The threshold intensity of the pump wave is greater than that in the case of subcritical plasma for TE polarization waves but can markedly decrease for waves polarized in the incidence plane. Instability is possible only for a layer of finite thickness.Radiophysical Research Institute, Nizhny Novgorod. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, Nos. 3–4, pp. 298–303, March–April, 1995. 相似文献
5.
Ivan Vitev 《Acta Physica Hungarica A》2006,27(2-3):281-286
We present an analytic model of jet quenching, based on the (D)GLV energy loss formalism, to describe the system size dependence of QGP-induced parton absorption in relativistic heavy ion collisions. Numerical simulations of the transverse momentum dependence of jet quenching are given for central Au+Au and Cu+Cu reactions. Low p Tdijet correlations are shown to be sensitive to the reappearance of the lost energy as soft hadrons. At high p Twe find that the attenuation of dihadrons is similar to that of single inclusive particles. Comparison to recent data from PHENIX and STAR is given as a test of the jet quenching theory. 相似文献
6.
Ivan Kojadinovic 《4OR: A Quarterly Journal of Operations Research》2007,5(2):117-142
The application of multi-attribute utility theory based on the Choquet integral requires the prior identification of a capacity
if the utility scale is unipolar, or of a bi-capacity if the utility scale is bipolar. In order to implement a minimum distance
principle for capacity or bi-capacity approximation or identification, quadratic distances between capacities and bi-capacities
are studied. The proposed approach, consisting in solving a strictly convex quadratic program, has been implemented within
the GNU R kappalab package for capacity and nonadditive integral manipulation. Its application is illustrated on two examples.
相似文献
7.
Anelia Achanova Ivan Zhelyazkov Tsvetelina Petrova 《Czechoslovak Journal of Physics》2004,54(2):211-223
Microwave discharges produced by travelling/standing electromagnetic waves have drawn considerable attention in recent years
due to their wide application in microelectronic industry. Here are presented the axial distributions of the electrons and
ions as well as those of excited atoms in an argon microwave discharge at a low gas pressure (400 mTorr) sustained by a 2.45
GHz travelling dipolar electromagnetic wave. The numerical calculations are based on a self-consistent kinetic-electrodynamic
model and the results obtained are in a good agreement with the experimental data. The model yields also the magnitude of
the wave power sustaining the discharge and the axial profiles of all electromagnetic-wave characteristics and the axial distribution
of the neutral gas temperature. 相似文献
8.
A. D. Lapin 《Acoustical Physics》2007,53(1):11-15
The problem of scattering of a Rayleigh wave by a chain of identical closely spaced monopole-dipole resonators with friction is considered. The values of resonator parameters that provide the rejection of the Rayleigh wave are found. The conditions under which the Rayleigh wave is much more efficiently reflected by the dipole resonators than by the monopole ones are determined. 相似文献
9.
Ivan Nunes da Silva Wagner Caradori do AmaralLucia Valeria de Arruda 《Applied Mathematical Modelling》2007
This paper presents an efficient approach based on recurrent neural network for solving nonlinear optimization. More specifically, a modified Hopfield network is developed and its internal parameters are computed using the valid subspace technique. These parameters guarantee the convergence of the network to the equilibrium points that represent an optimal feasible solution. The main advantage of the developed network is that it treats optimization and constraint terms in different stages with no interference with each other. Moreover, the proposed approach does not require specification of penalty and weighting parameters for its initialization. A study of the modified Hopfield model is also developed to analyze its stability and convergence. Simulation results are provided to demonstrate the performance of the proposed neural network. 相似文献
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