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991.
992.
In this paper, the existence and multiplicity of positive solutions is established for Schrödinger‐Poisson system of the form where 0 ∈ Ω is a smooth bounded domain in , , and λ > 0 is a real parameter. Combining with the variational method and Nehari manifold method, two positive solutions of the system are obtained. 相似文献
993.
994.
995.
996.
In this paper, we study the following Klein–Gordon–Maxwell system Using variational methods, we obtain the existence of ground state solutions under some appropriate assumptions on and . 相似文献
997.
This article is devoted to the problem of robust stabilization of uncertain nonlinear switched systems with canonical structure. It is assumed that the constant parameters of the subsystems are unknown and cannot be adopted in the controller design. In addition, the dynamics of the subsystems are perturbed via modeling errors and external disturbances. The effects of unknown actuator saturation are compensated via proper adaptive control signals. The derived controller is based on the terminal sliding mode theory and does not need any prior knowledge about the bounds of the lumped uncertain terms. It is proved that once the system states reach the prescribed sliding manifold in a finite time interval, the whole system becomes insensitive to both the lumped uncertainties and the switching dynamics of the system. The common assumption of having known quadratic Lyapunov functions for the subsystems is relaxed and the derived adaptive approach does not force any limitation on the switching signal of the system. Subsequently, non-conservative conditions are provided to guarantee the global finite time bounded stability of the equilibrium state for the overall uncertain nonlinear switched system under arbitrary switching signals. A numerical computer simulation demonstrates the robust performance of the proposed controller. 相似文献
998.
We construct a class of integrable generalization of Toda
mechanics with long-range interactions. These systems are
associated with the loop algebras L(Cr) and L(Dr) in the sense that their Lax matrices can be realized in
terms of the c=0 representations of the affine Lie algebras
C(1)r and
D(1)r and the interactions pattern involved
bears the typical characters of the corresponding root systems. We
present the equations of motion and the Hamiltonian structure.
These generalized systems can be identified unambiguously by
specifying the underlying loop algebra together with an ordered
pair of integers (n,m). It turns out that different systems
associated with the same underlying loop algebra but with
different pairs of integers
(n1,m1) and (n2,m2) with
n2<n1 and
m2<m1 can be related by a nested Hamiltonian
reduction procedure. For all nontrivial generalizations, the extra
coordinates besides the standard Toda variables are Poisson
non-commute, and when either $n$ or
m≥3, the Poisson
structure for the extra coordinate variables becomes some Lie
algebra (i.e. the extra variables appear linearly on the
right-hand side of the Poisson brackets). In the quantum case, such
generalizations will become systems with noncommutative variables
without spoiling the integrability. 相似文献
999.
LIU Xin DUAN Yi-Shi ZHANG Peng-Ming 《理论物理通讯》2005,44(8)
The skyrmions in SU(N) quantum Hall (QH) system are discussed. By analyzing the gauge field structure and the topological properties of this QH system it is pointed out that in the SU( N) QH system there can exist ( N - 1)types of skyrmion structures, instead of only one type of skyrmions. In this paper, by means of the Abelian projections according to the (N - 1) Cartan subalgebra local bases, we obtain the (N - 1) U(1) electromagnetic field tensors in the SU(N) gauge field of the QH system, and then derive (N - 1) types of skyrmion structures from these U(1) sub-field tensors. Furthermore, in light of the φ-mapping topological current method, the topological charges and the motion of these skyrmions are also discussed. 相似文献
1000.
ZHOU Yun ZHU Shi-Qun WU Liang 《理论物理通讯》2005,44(12)
In a coupled laser system, the dynamics of the receiving laser is investigated when two separate transmitting lasers are injected into the receiving laser with different coupling strengths. It is shown that the phenomenon of preference of chaotic synchronization appears under appropriate coupling conditions. The receiving laser will entrain the pulses of either one or both transmitting lasers when the coupling is strong while it keeps its own dynamics when the coupling is weak. 相似文献