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Zhang R.-X.,Hebei Normal University | Zhang R.-X.,Hebei Advanced Thin Films Laboratory | Zhang R.-X.,Xingtai University | Yang S.-P.,Hebei Normal University | Yang S.-P.,Hebei Advanced Thin Films Laboratory
Chinese Physics B | Year: 2010

A new stability theory of nonlinear dynamic systems is proposed, and a novel adaptive synchronisation method is presented for fractional-order chaotic and hyperchaotic systems based on the theory described in this paper. In comparison with previous methods, not only is the present control scheme simple but also it employs only one control strength, converges very fast, and it is also suitable for a large class of fractional-order chaotic and hyperchaotic systems. Moreover, this scheme is analytical and simple to implement in practice. Numerical and circuit simulations are used to validate and demonstrate the effectiveness of the method. © 2010 Chinese Physical Society and IOP Publishing Ltd.

Song L.-H.,Hebei Normal University | Song L.-H.,Hebei Advanced Thin Films Laboratory | Song L.-H.,Hebei Polytechnic University | Duan C.-G.,Hebei Normal University | Duan C.-G.,Hebei Advanced Thin Films Laboratory
Physical Review C - Nuclear Physics | Year: 2010

Semi-inclusive deep inelastic scattering on nuclear targets is an ideal tool to study the energy loss effect of an outgoing quark in a nuclear medium. By means of the short hadron formation time, the experimental data with quark hadronization occurring outside the nucleus are picked out. A leading-order analysis is performed for the hadron multiplicity ratios as a function of the energy fraction on helium, neon, and copper nuclei relative to deuteron for the various identified hadrons. It is shown that the nuclear effects on parton distribution functions can be neglected. It is found that the theoretical results considering the nuclear modification of fragmentation functions due to quark energy loss are in good agreement with the experimental data. Whether the quark energy loss is linear or quadratic with the path length is not determined. The obtained energy loss per unit length is 0.38±0.03 GeV/fm for an outgoing quark by the global fit. © 2010 The American Physical Society.

Yuan G.,Hebei Normal University | Yuan G.,Hebei Advanced Thin Films Laboratory | Liu Y.,Hebei Normal University | Xu A.,CAS Beijing Institute of Applied Physics And Computational Mathematics | Wang G.,CAS Beijing Institute of Applied Physics And Computational Mathematics
Nonlinear Dynamics | Year: 2012

We study the effects of a dichotomous periodic force on meandering and rigidly rotating spiral waves. For a meandering state, the periodic forcing induces more modulating frequencies according to the rules of frequency-locked relations and linear combinations. It can also generate some unique closed tip orbits. On the modulating period T-axis, there exist all kinds of resonant entrainment bands. Arnold tongues exist in the period-amplitude space. The width of entrainment bands is affected by the symmetry of positive and negative parts in each signal unit. In addition, appropriate choices of T-value can be used to eliminate spiral waves. For a rigidly rotating state, the periodic forcing can induce a transition toward meandering spiral waves via generating a transitive bidirectional spiral wave. It is very interesting that, after the transition, the meandering spiral wave has the same primary rotating period as the free meandering states. © Springer Science+Business Media B.V. 2012.

Liang S.,Hebei Normal University | Li H.,Hebei Normal University | Shen X.,Hebei Advanced Thin Films Laboratory | Cui W.,Hebei Advanced Thin Films Laboratory | Zhang B.,Hebei Advanced Thin Films Laboratory
Publications of the Astronomical Society of the Pacific | Year: 2012

The chemical abundances of the r + s stars can give us excellent information for setting constraints on models of s- and r-process nucleosynthesis. In this article, we fit the element abundances of 32 r + s or s-rich stars by using a parametric model.We find that the r-process abundance pattern related to r + s stars is similar to the pattern of r-rich stars. On the other hand, the abundance pattern of light elements and iron group elements for the r + s stars is very close to the pattern for weak r-process stars. The r + s stars and r-rich stars are initially formed in the molecular cloud, which had been polluted by weak r-process material. The yields of r-process related to r + s stars are proportional to their metallicity. Although the origin and site of the s-process are quite different from those of the r-process, there is a strong correlation between the enhancement level of the s-process and r-process in r + s stars. This implies that r-process matter accreted from the origin of the r-process, such as AIC or SN 1.5, has an increasing trend with increasing s-process matter accreted from the AGB stars. © 2012. The Astronomical Society of the Pacific.

Yuan G.-Y.,Hebei Normal University | Yuan G.-Y.,Hebei Advanced Thin Films Laboratory
Chinese Physics B | Year: 2011

We numerically study the dynamics of spiral waves in the excitable system with the excitability modulated by a rectangle wave. The tip trajectories and their variations with the modulation period T are explained by the corresponding spectrum analysis. For a large T, the external modulation leads to the occurrence of more frequency peaks and these frequencies change with the modulation period according to their specific rules, respectively. Some of the frequencies and a primary frequency f1 determine the corresponding curvature periods, which are locked into rational multiplies of the modulation period. These frequency-locking behaviours and the limited life-span of the frequencies in their variations with the modulation period constitute many resonant entrainment bands in the T axis. In the main bands, which follow the relation T/T12 = m/n, the size variable Rx of the tip trajectory is a monotonic increasing function of T. The rest of the frequencies are linear combinations of the two ones. Due to the complex dynamics, many unique tip trajectories appear at some certain T. We find also that spiral waves are eliminated when T is chosen from the end of the main resonant bands. This offers a useful method of controling the spiral wave. © 2011 Chinese Physical Society and IOP Publishing Ltd.

Wang M.-Y.,Hebei Normal University | Wang M.-Y.,Hebei Advanced Thin Films Laboratory | Yan F.-L.,Hebei Normal University | Yan F.-L.,Hebei Advanced Thin Films Laboratory
Chinese Physics B | Year: 2011

In this paper, we investigate perfect quantum teleportation and dense coding by using an 2N-qubit W state channel. In the quantum teleportation scheme, an unknown N-qubit entangled state can be perfectly teleported. One ebit of entanglement and two bits of classical communication are consumed in the teleportation process, just like when using the Bell state channel. While N + 1 bits of classical information can be transmitted by only sending N particles in the dense coding protocol. © 2011 Chinese Physical Society and IOP Publishing Ltd.

An X.-T.,Hebei University of Science and Technology | An X.-T.,Hebei Normal University | Liu J.-J.,Hebei Normal University | Liu J.-J.,Hebei Advanced Thin Films Laboratory
Applied Physics Letters | Year: 2010

We study the spin polarization and the spin accumulation in an Aharonov-Bohm ring structure, in which a quantum dot (QD) array is side-coupled to one arm of the ring and the Rashba spin-orbit interaction exists in the other. The device can be as a spin switch by decreasing the tunneling coupling between the QD array and the ring. Moreover, we find that the spin polarization and the spin accumulation in the QD are affected by the number of the QDs in the QD array and can be controlled by the strength of the Rashba spin-orbit interaction and the bias on the Aharonov-Bohm ring. © 2010 American Institute of Physics.

Meng Y.,Hebei Normal University | Meng Y.,Hebei Advanced Thin Films Laboratory | An Z.,Hebei Normal University | An Z.,Hebei Advanced Thin Films Laboratory
European Physical Journal B | Year: 2010

Within an extended Su-Schrieffer-Heeger model including interchain interactions and the extended Hubbard model (EHM), the dynamical relaxation of photoexcitations in the presence of an external electric field is investigated using a nonadiabatic evolution method. Under the action of the interchain interactions both intrachain excitons and interchain excitons are generated after photoexcitation in two coupled polymer chains. Our results show that the field required to dissociate the excitons depends sensitively on the strength of the interchain coupling. As the interchain coupling strength increases, the dissociation field decreases. By analyzing the relation between the yield of intrachain and interchain excitons and the interchain coupling strength, we explain the dependence between the dissociation field and the strength of the interchain interactions. The theoretical results are expected to provide useful predictions concerning which polymers with properly strong interchain interactions are likely to be most suitable for use in organic solar cells. © 2010 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg.

Yuan G.-Y.,Hebei Normal University | Yuan G.-Y.,Hebei Advanced Thin Films Laboratory
Communications in Theoretical Physics | Year: 2011

We numerically study the dynamics of meandering spiral waves in the excitable system subjected to a feedback signal coming from two measuring points located on a straight line together with the initial spiral core. The core location and size radius of the final attractors are computed, and they change with the position of the moving measuring point in a unique way. By the Fourier Spectral analysis, we find the frequency-locked behaviors different from the driving scheme of the external periodic force. It is also found that the meandering spiral wave can be eliminated when the moving measuring point approaches closely the boundary and its feedback gain is large enough. This offers an effective and convenient method for eliminating meandering spiral waves. © 2011 Chinese Physical Society and IOP Publishing Ltd.

Yuan G.,Hebei Normal University | Yuan G.,Hebei Advanced Thin Films Laboratory | Zhang H.,Hebei Normal University | Zhang H.,Hebei Advanced Thin Films Laboratory | And 2 more authors.
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2013

The attracting and repelling of spiral waves in a two-dimensional excitable medium in the presence of localized excitability inhomogeneities are studied. The choice of two effects depends on the comparison of excitabilities inside and outside the localized obstacle. We inspect the changes in attracting and repelling behaviors with respect to the size of the obstacle and the initial distance between the center of the spiral core and the obstacle. To understand the occurrence of these phenomena, we investigated the small v-value areas near the tip and the function of the wave velocity as the excitability parameter É. Considering the attributes of the attractive obstacle, an eliminating scheme of spiral waves is proposed in which the attractive obstacle is rapidly moved at several fixed times. This method can avoid the high-amplitude and high-frequency stimulus in most conventional methods. © 2013 American Physical Society.

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