Zhu Y.,Jiangxi University of Science and Technology |
Zheng Z.,Beijing Normal University |
Yang J.,Beijing University of Posts and Telecommunications
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2014
The model of nonlocally coupled identical phase oscillators on complex networks is investigated. We find the existence of chimera states in which identical oscillators evolve into distinct coherent and incoherent groups. We find that the coherent group of chimera states always contains the same oscillators no matter what the initial conditions are. The properties of chimera states and their dependence on parameters are investigated on both scale-free networks and Erdös-Rényi networks. © 2014 American Physical Society.
Liu C.-F.,Jiangxi University of Science and Technology |
Liu C.-F.,CAS Institute of Physics |
Liu W.M.,CAS Institute of Physics
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012
We investigate the half-skyrmion excitations induced by spin-orbit coupling in the rotating and rapidly quenched spin-1 Bose-Einstein condensates. We give three expressions of the corresponding spin vectors to describe the half-skyrmion. Our results show that the half-skyrmion excitation depends on the combination of spin-orbit coupling and rotation, and it originates from a dipole structure of spin which is always embedded in three vortices constructed by each condensate component respectively. When both the strength of spin-orbit coupling and the rotation frequency are larger than some critical values, the half-skyrmions encircle the center with one or several circles to form a radial lattice, which occurs even in the strong ferromagnetic/antiferromagnetic condensates. We can use both the spin-orbit coupling and the rotation to adjust the radial lattice. The realization and the detection of the half-skyrmions are compatible with current experimental technology. © 2012 American Physical Society.
Xiao X.,Gannan Normal University |
Li Y.-L.,Jiangxi University of Science and Technology
European Physical Journal D | Year: 2013
Entangled states in high dimensional systems are of great interest due to the extended possibilities they provide in quantum information processing. Recently, Sun et al. [Phys. Rev. A 82, 052323 (2010)] and Kim et al. [Nat. Phys. 8, 117 (2012)] pointed out that weak measurement and quantum weak measurement reversal can actively combat decoherence. We generalize their studies from qubits to qutrits under amplitude damping decoherence. We find that the qutrit-qutrit entanglement can be partially retrieved for certain initial states when only weak measurement reversals are performed. However, we can completely defeat amplitude damping decoherence for any initial states by the combination of prior weak measurements and post optimal weak measurement reversals. The experimental feasibility of our schemes is also discussed. © EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2013.
Yu C.,Jiangxi University of Science and Technology |
Yu C.,Carnegie Mellon University |
Li G.,Carnegie Mellon University |
Kumar S.,Carnegie Mellon University |
And 2 more authors.
Advanced Materials | Year: 2014
Coreshell-like Ag2O/Ag2CO3 nanoheterostructures with tailored interface are fabricated by a facile, low-cost and one-step phase transformation method. The unique bandgap structure of the Ag2O/Ag2CO3 exhibits high separation efficiency of photogenerated electrons and holes, which effectively protects the Ag2CO3 semiconductor to avoid its photoreduction and gives rise to high activity and stability in degradation of the typical water pollutants. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Li J.,Jiangxi University of Science and Technology
Proceedings of the 2012 4th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2012 | Year: 2012
Differential evolution (DE) is a popular optimization technique, however it also tends to suffer from premature convergence. One possible way to fix this problem is adaptively to choose the right mutation strategy and control parameter setting for distinct problems. Recently, a new concept, opposition-based learning, was introduced to computational intelligent, which was experimentally proven to be effective and robust. Therefore, a new approach is proposed to combine these two means in attempt to enhance the ability of DE. In the proposed approach, one solution produced by different mutation strategies and parameter setting is used to generate the corresponding opposite one, and then these two solutions are simultaneously evaluated to make the better one as the offspring. The experiments are conducted on 13 well-known benchmark functions, and the experimental results compared with other several state-of-the-art DE variants show that the proposed approach is effective and robust. Copyright © 2012 by The Institute of Electrical and Electronics Engineers, Inc.
Cheng J.,Jiangxi University of Science and Technology
Advanced Materials Research | Year: 2012
In the premise of achieving corresponding functions, sustainable design means to take the most natural, harmless and energy-saving materials to realize the product functions to meet the need of the present without compromising the ability of future generation to meet their own needs. While with the Chinese characteristic features and the endless expansion demand on consumption, design is going on the opposite direction. The product design research based on sustainable concept is a re-examined view of human-oriented design in front of the challenge of limited resources protection. And with the help of unlimited creativities and design, we can care more about our nature and society on one hand. On the other hand, the silent affection and promotion on green, energy-saving and low-carbon living concept will also definitely influence our human being to be more rational. © (2012) Trans Tech Publications.
Liu Z.,Jiangxi University of Science and Technology
International Journal of Theoretical Physics | Year: 2013
We investigate the entanglement property of a four-qubit state superposed by a four-qubit GHZ state and a symmetric state with spin squeezing. Numerically and analytic solutions for spin squeezing parameters are given. The squeezed parameters depend on the superpose coefficients and the relative phases. It is shown that there is no spin squeezing at n1 direction and it occurs at n2 direction under some conditions. © 2012 Springer Science+Business Media New York.
Hu J.,Jiangxi University of Science and Technology
International Journal of Advancements in Computing Technology | Year: 2012
A discrete variable structure control methodology is presented to suppress vibration of high-speed flexible parallel robot. The elastic dynamic model of the flexible robot is built by using the finite element method and experimental modal testing. Considering uncertain external disturbances and measurement noise, and uncertain parameters of the system, we can utilize invariance of the sliding mode of variable structure control in order to eliminate these adverse influences. The discrete variable structure control strategy is employed to construct the vibration robust controller which enables the flexible robot to be zero state so that the system states are away from the equilibrium one due to external disturbances and uncertain parameters. The discrete Kalman filter is constructed to as state estimator because the state variables cannot be directly measured. The first four natural frequencies and damping ratio are obtained by using experimental modal testing, and the correctness of theoretical model is verified. The experimental vibration control system is constructed and experimental validation of the controller is carried out using dSPACE real-time control system and MATLAB/Simulink tool. The experimental results showed that the proposed controller can effectively alleviate the vibration response of the high-speed flexible robot.
Hu J.-F.,Jiangxi University of Science and Technology |
Zhang X.-M.,South China University of Technology
Guangxue Jingmi Gongcheng/Optics and Precision Engineering | Year: 2012
To achieve the precise motion of a 3-RRR compliant parallel precision positioning stage, a closed-form exact motion model was established and the optimized design of structure parameters was investigated. The Castigliano's second theorem was applied to establishment of the closed-form compliance model for the precision positioning stage. According to the structural characteristics of compliant parallel mechanisms, the system was divided into three symmetrical motion sub-chains. Combining the compliance equations of flexure hinge with the force transmission relations of mechanisms, the stiffness model of each sub-chain was obtained, and the stiffness of the entire system was calculated by summing the stiffness of three sub-chains in the same coordinate system. The proposed stiffness model took the hinge flexibility as the independent variables in the closed form. According to the flexibility matrix, the Jacobian matrix to reflect the relationship between input displacement and output one could be derived. By comparing the kineamatic model between theoretical analysis and FEA, the results show that the errors are within 1.0%~9.5%, which illurastrates that the proposed kinematic model is correct and precise. According to the closed-form Jacobian matrix, its sensitivity to structureal parameters was analyzed, then the design variables with greater impact on the kinematic properties were chosen. By taking the maxmium workspace as a target and the hinge strength, maxmium input forces, geometric dimensions and input coupling as the constrains, an optimal model was proposed. The results show that the optimized structural parameters can obtain more output displacements, and the proposed model can meet the design requirement.
Hu J.,Jiangxi University of Science and Technology
Proceedings - 2012 International Conference on Intelligent Systems Design and Engineering Applications, ISDEA 2012 | Year: 2012
For a novel 2-DoF flexible parallel manipulator, its kinematic and vibration control was investigated based on the inverse dynamic model by using sliding mode control. Taking into account the complexity of rigid-flexible coupling effect of the flexible manipulator, the assumed mode method and Lagrange multiplier method were applied to derive the dynamic equations of the system. It is a differential algebraic equation. In order to design conveniently the controller based on the model, the coordinate-partitioned method was used to convert the differential algebraic equations into a second-order differential one. According to the demand of motion and vibration control, the sliding mode control method was applied to design the controller in order to obtain the desired trajectory and attenuate the elastic deformation of flexible manipulator. The numerical simulation results showed the proposed controller can eliminate the deflections of the midpoint of the flexible part and have a good trajectory track performance. © 2012 IEEE.