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排序方式: 共有5292条查询结果,搜索用时 93 毫秒
991.
The classical variational inequality problem with a Lipschitzian and strongly monotone operator on a nonempty closed convex subset in a real Hilbert space is studied. A new three-step relaxed hybrid steepest-descent method for this class of variational inequalities is introduced.Strong convergence of this method is established under suitable assumptions imposed on the algorithm parameters. 相似文献
992.
In this paper, the limit case of the SD (smooth and discontinuous) oscillator is studied. This system exhibits standard dynamics governed by the hyperbolic structure associated with the stationary state of the double-well. The substantial deviation from the standard dynamics is the non-smoothness of the velocity in crossing from one well to another, caused by the loss of local hyperbolicity due to the discontinuity. Without dissipation, the KAM structure on the Poincaré section is constructed with generic KAM curves and a series of fixed points associated with surrounded islands of quasi-periodic orbits and the chaotic connection orbits. It is found that, for a fixed set of parameters, a special chaotic orbit exits there which fills a finite region and connects a series of islands dominated by different chains of fixed points. As one adds weak dissipation, the periodic solutions in this finite region remain unchanged while the quasi-periodic solutions (isolated islands) are converted to the corresponding periodic solutions. The relevant dynamics for the system with weak dissipation under external excitation is shown having period doubling bifurcation leading to chaos, and multi-stable solutions. 相似文献
993.
According to the integral type constitutive relation of linear coupled thermoviscoelasticity, a mathematical model of thin plates is set up by the introduction of “structural functions” and “thermal functions” in the sense of the Kirchhoff’s hypothesis. The corresponding integral type variational formulations are presented by means of modern convolution bilinear forms as well as classical Cartesian bilinear forms. The Ritz method in the spatial domain and the differentiating method in the temporal domain are used to approximate the mathematical model in a system of rectangular Cartesian coordinates. By properties of inequality and parabola, the structure of dynamic solution to vibration of a thermoviscoelastic thin plate under a harmonic thermal load is studied in the space splayed by material parameter and loading parameter. The influences of thermal excitation frequency, mechanical relaxation time and thermal relaxation time on amplitude and phase difference of steady-state vibration of a square plate are investigated by amplitude-frequency analysis and phase-frequency analysis. Double-peak resonance vibration of thermoviscoelastic plates exists for given parameters. 相似文献
994.
Measure synchronization in coupled Hamiltonian systems is a novel
synchronization phenomenon. The measure synchronization on symplectic map is
observed numerically, for identical coupled systems with different
parameters. We have found the properties of the characteristic frequency and
the amplitude of phase locking in regular motion when the measure
synchronization of coupled systems is obtained. The relations between the
change of the largest Lyapunov exponent and the course of phase
desynchronization are also discussed in coupled systems, some useful results
are obtained. A new approach is proposed for describing the measure
synchronization of coupled systems numerically, which is
advantage in judging the measure synchronization, especially for the coupled
systems in nonregular region. 相似文献
995.
By means of the standard truncated Painlevé expansion and a special Bäcklund transformation, the
higher-dimensional coupled Burgers system (HDCB) is reduced to a linear equation, and an exact multisoliton
excitation is derived. The evolution properties of the multisoliton excitation are investigated and some
novel features or interesting behaviors are revealed. The results
show that after interactions for dromion-dromion,
solitoff-solitoff, and solitoff-dromion, they are combined with some
new types of localized structures, which are similar to classic
particles with completely nonelastic behaviors. 相似文献
996.
A general mapping approach and new travelling wave solutions to the general variable coefficient KdV equation 下载免费PDF全文
A general mapping deformation method is applied to a generalized variable coefficient KdV equation. Many new types of exact solutions, including solitary wave solutions, periodic wave solutions, Jacobian and Weierstrass doubly periodic wave solutions and other exact excitations are obtained by the use of a simple algebraic transformation relation between the generalized variable coefficient KdV equation and a generalized cubic nonlinear Klein-Gordon equation. 相似文献
997.
We establish some inequalities for the inradius, circumradius and distances between an interior point and facets of an n-simplex, and prove a recursion inequality for the radii of the circumscribed spheres of an n-simplex and its facets. 相似文献
998.
999.
1000.
Statistical Structure at the Wall of the High Reynolds Number Turbulent Boundary Layer 总被引:1,自引:0,他引:1
The one and two-point statistical structure of very high Reynolds number turbulence in the surface layer near a rigid `wall'
is analysed. The essential mechanisms for turbulent eddies impinging on the wall are studied using linearised rapid distortion
theory, which show how the mean shear and blocking actions of the surface act first independently and then, over the life
time of the eddy, interactively. Previous analytical results are reinterpreted and some new results are derived to show how
the integral length scales, cross correlations and spectra of the different components of the turbulence are distorted depending
on the form of the spectra of eddies above the surface layer and how they are related to motions of characteristic eddy structures
near the surface. These results are applied to derive some quantitative and qualitative predictions in the surface layers
(SL), where the eddies are affected by local shear dynamics, and in the `eddy surface layer' (ESL) where quasi independents
loping elongated eddies interact directly with the wall, and where there is a large range of wave number within which the
spectra of the horizontal velocity components are proportional to k
−1. The longest eddies in the boundary layer occur near the wall. Field experiments agree with the theoretical model predictions
for the quite different forms for the spectra, cospectra and cross correlations for the vertical and horizontal components
of the velocity field. By showing that in SL the energy exchange between the large and small scale eddies is local(`staircase')
energy cascade, whereas in ESL there is a direct nonlocal (`elevator-like')energy transfer to the small scales, it is shown
why the thickness of the ESL increases over rougher surfaces and as the Reynolds number decreases.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献