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991.
《Chaos, solitons, and fractals》2005,23(3):887-908
A discrete genetic toggle switch system obtained by Euler method is first investigated. The conditions of existence for fold bifurcation and flip bifurcation are derived by using center manifold theorem and bifurcation theory. The numerical simulations, including bifurcation diagrams, phase portraits, and computation of Lyapunov exponents, not only show the consistence with the theoretical analysis but also exhibit the rich and complex dynamical behavior. We show the period 3 to 13 windows in different chaotic regions, period-doubling bifurcation or inverse period-doubling bifurcation from period-2 to 12 orbits leading to chaos, different kind of interior crisis and boundary crisis, intermittency behavior, chaotic set, chaotic non-attracting set, coexistence of period points with invariant cycles, and so on. The influence of the amplitude and frequency of excitable forcing on the system are also first considered by using numerical simulation. A different type of quasiperiodic orbits, jumping behaviors of quasiperiodic set from one set to another set, and the processes from quasiperiodic orbits to strange non-chaotic attractor are found. 相似文献
992.
设B(t)=(B(t))=(B1(t),B2(t),…,BN(t))为N维Brown运动,设α(x)=(αij(x),1(≤)I(≤)d,1(≤)j(≤)N),β(x)=(βi(x),1(≤)I(≤)d),x∈Rd,1(≤)d(≤)N,α(x)和β(x)有界连续和满足Lipchitz条件,且存在常数c0>0,使得对每个x∈Rd,a(x)=α(x)α(x)*的每个特征根都不小于c0.设dX(t)=α(X(t))dB(t) β(X(t))dt,设d(≥)3.可以证明P(ωDimX(E,ω)=DimGRX(E,ω)=2DimE,(A)E∈B[0,∞))=1.这里X(E,ω)={X(t,ω)t∈E},GRX(E,ω)={(t,X(t,ω))t∈E},DimF表示F的Packing维数. 相似文献
993.
Quantum entanglement and quantum nonlocality of N-photon entangled states |\psiN m\rangle
=Cm[\cos\gamma|N-m\rangle1|m\rangle2 +\e{\i\θm}\sin\gamma|m\rangle1|N-m\rangle2] and their superpositions are studied. We point out that the relative
phase θm affects the quantum nonlocality but not the quantum
entanglement for the state |\psiN m\rangle. We show that
quantum nonlocality can be controlled and manipulated by adjusting
the state parameters of |\psiN m\rangle, superposition
coefficients, and the azimuthal angles of the Bell operator. We
also show that the violation of the Bell inequality can reach its
maximal value under certain conditions. It is found that quantum
superpositions based on |\psiN m\rangle can increase the
amount of entanglement, and give more ways to reach the maximal
violation of the Bell inequality. 相似文献
994.
在本文中,我们引进了极小内射模、极小平模模以及M.P环的概念,给出了它们的一些特征刻画,并用这两类模刻画了D edek ind环,VN正则环. 相似文献
995.
996.
This paper investigates the existence of periodic solutions for an impulsive semi-ratio-dependent predator–prey system with most popular prey-dependent (monotone or non-monotone) and predator-dependent functional response. Sharp sufficient conditions are derived by the invariance property of homotopy and analysis technique. The presented criteria improve and extend many previous results in the literature. 相似文献
997.
Molecular dynamics methods are employed for a comparative study of the spread of nanosized simple fluid droplets and nanodroplets
composed of model chains that reflect molecules of normal alkanes over a solid substrate. The effects of the droplet size,
the energy of the molecule-substrate interactions, temperature, and degree of chain rigidity on the spreading kinetics are
investigated. The substrate is described in terms of the continual Lennard-Jones model. 相似文献
998.
线性流形上矩阵方程AX=B的一类反问题及数值解法 总被引:10,自引:0,他引:10
1.引言本文用*-"m表示全体nX。实矩阵的集合,人表示n阶单位矩阵,汉"m一《ME*""叫rank(川一r),**"""=HE*"""卜"A=v,**"""一仰E*"""卜"一M},SR;""(SR7"")表示全体7。阶实对称半正定(正定)阵集合.N(A)表示矩阵A的零空间,即N(A)=(xlAx=0),ID叫D表示Frobenius范数,A"表示矩阵A的Moors-Penrose广义逆,[EI十表示在Frobenius范数意义下n阶方阵E在SR;""中唯一的最佳k逼近解,即口一[E]+11-inf。。、。。x,IllE-All.([E]十求法见文[7]).还用A三0(A三0)表示A(的k阶顺序主子矩… 相似文献
999.
A connected loopless graph that can be embedded on some (orientable or nonorientable) surface such that the size of each face
does not exceed 5 is upper embeddable. 相似文献
1000.
恰有d个正对角元的布尔矩阵的幂敛指数的分布 总被引:2,自引:0,他引:2
设Bn为n阶布尔矩阵的集合,Dn(d)={A∈Bn|A中恰有d个正对角元,本文完全确定了矩阵类Dn(d)的幂敛指数集kn(d). 相似文献