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991.
江月松  钟宇  李亮 《光学技术》2005,31(2):200-201
瞄准制导仪中的调制盘光学系统包含有光束投射系统、光束投影系统和旋转调制盘。基于旋转调制盘图案设计的原理,分析了瞄准制导仪中内、外调制图案与光学系统的配合问题。较详细地分析了激光束投射系统和投影系统。  相似文献   
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.
方建平  郑春龙  朱加民 《物理学报》2005,54(7):2990-2995
利用拓展的Riccati方程映射法,得到了(2+1)维Boiti-Leon-Pempinelli系统新的变量分离 解.根据得到的分离变量解,构造出该系统新型的孤子结构——方孤子和分形孤子. 关键词: Boiti-Leon-Pempinelli系统 拓展Riccati映射 方形孤子 分形孤子  相似文献   
994.
电力安全与超导磁储能系统   总被引:1,自引:0,他引:1  
随着我国大规模电力系统的逐步形成,电网的安全稳定问题日渐突出,保证电力系统的安全稳定运行已经成为电网发展和运行的重要任务.超导磁储能系统以其对系统功率需求的快速响应特性可以为提高电力系统的稳定性提供新的技术途径,同时对改善电能质量、提高可靠性也有很好的技术优势.本文在简要论证电力安全的重要性的基础上,对SMES提高系统的安全稳定性的优越性进行了分析,并介绍了国家863计划项目“高温超导磁储能系统”的工作进展.  相似文献   
995.
996.
In this paper, we study the following Klein–Gordon–Maxwell system Δu+(λa(x)+1)u(2ω+ϕ)ϕu=f(x,u),inR3,Δϕ=(ω+ϕ)u2,inR3.Using variational methods, we obtain the existence of ground state solutions under some appropriate assumptions on a and f.  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.
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.
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   
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