The recently proposed method of our research group named as directional Lyapunov exponents（DLEs） is presented. Then, DLEs are used to analyze the eigenstructure of the output phase space around the equilibrium point...The recently proposed method of our research group named as directional Lyapunov exponents（DLEs） is presented. Then, DLEs are used to analyze the eigenstructure of the output phase space around the equilibrium points. Finally, the impacts of the superlattice parameter changes on the characteristics of the output chaotic signal are analyzed. The experimental results show that parameter changes of the superlattice will affect the eigenstructure around the equilibrium points in the output phase space, and DLEs are sensitive to these changes.展开更多
It is found that in free space, the curves of the mean-squared beam width may each have a cross point at a certain propagation distance Zc. For Gaussian array beams, the analytical expressions of zc are derived. For t...It is found that in free space, the curves of the mean-squared beam width may each have a cross point at a certain propagation distance Zc. For Gaussian array beams, the analytical expressions of zc are derived. For the coherent com- bination, Zc is larger than that for the incoherent combination. However, in non-Kolmogorov turbulence, the cross point disappears, and the Gaussian array beams will have the same directionality in terms of the angular spread. Furthermore, a short propagation distance is needed to reach the same directionality when the generalized exponent is equal to 3.108. In particular, it is shown that the condition obtained in previous studies is not necessary for laser beams to have the same directionality in turbulence, which is explained physically. On the other hand, the relative average intensity distributions at the position where the Gaussian array beams have the same mean-squared beam width are also examined.展开更多
为解决传统JPS(Jump Point Search)算法的拐点多和路径次优等问题,提出一种改进的跳点搜索算法。首先,根据地图可行率,对障碍物进行适应性膨胀,以保障安全距离;其次,结合方向性因素对启发函数进行调整,显著提高了路径搜索的目的性;最后...为解决传统JPS(Jump Point Search)算法的拐点多和路径次优等问题,提出一种改进的跳点搜索算法。首先,根据地图可行率,对障碍物进行适应性膨胀,以保障安全距离;其次,结合方向性因素对启发函数进行调整,显著提高了路径搜索的目的性;最后,提出了一种能剔除冗余节点的关键点提取策略,优化了初始规划后的路径,在保证路径最短的同时,显著减少了拓展节点和拐角。实验结果表明,与传统的JPS算法相比,所提算法能缩短路径长度并减少拐角数量,同时拓展节点数量平均减少19%,搜索速度平均提升21.8%。展开更多
The alternating direction method of multipliers （ADMM for short） is efficient for linearly constrained convex optimization problem. The practicM computationM cost of ADMM depends on the sub-problem solvers. The prox...The alternating direction method of multipliers （ADMM for short） is efficient for linearly constrained convex optimization problem. The practicM computationM cost of ADMM depends on the sub-problem solvers. The proximal point algorithm is a common sub-problem-solver. However, the proximal parameter is sensitive in the proximM ADMM. In this paper, we propose a homotopy-based proximal linearized ADMM, in which a homotopy method is used to soNe the sub-problems at each iteration. Under some suitable conditions, the global convergence and the convergence rate of O（1/k） in the worst case of the proposed method are proven. Some preliminary numerical results indicate the validity of the proposed method.展开更多
文摘The recently proposed method of our research group named as directional Lyapunov exponents（DLEs） is presented. Then, DLEs are used to analyze the eigenstructure of the output phase space around the equilibrium points. Finally, the impacts of the superlattice parameter changes on the characteristics of the output chaotic signal are analyzed. The experimental results show that parameter changes of the superlattice will affect the eigenstructure around the equilibrium points in the output phase space, and DLEs are sensitive to these changes.
基金supported by the National Natural Science Foundation of China(Grant No.61178070)the Construction Plan for Scientific Research Innovation Teams of Universities in Sichuan Province,China(Grant No.12TD008)
文摘It is found that in free space, the curves of the mean-squared beam width may each have a cross point at a certain propagation distance Zc. For Gaussian array beams, the analytical expressions of zc are derived. For the coherent com- bination, Zc is larger than that for the incoherent combination. However, in non-Kolmogorov turbulence, the cross point disappears, and the Gaussian array beams will have the same directionality in terms of the angular spread. Furthermore, a short propagation distance is needed to reach the same directionality when the generalized exponent is equal to 3.108. In particular, it is shown that the condition obtained in previous studies is not necessary for laser beams to have the same directionality in turbulence, which is explained physically. On the other hand, the relative average intensity distributions at the position where the Gaussian array beams have the same mean-squared beam width are also examined.
文摘为解决传统JPS(Jump Point Search)算法的拐点多和路径次优等问题,提出一种改进的跳点搜索算法。首先,根据地图可行率,对障碍物进行适应性膨胀,以保障安全距离;其次,结合方向性因素对启发函数进行调整,显著提高了路径搜索的目的性;最后,提出了一种能剔除冗余节点的关键点提取策略,优化了初始规划后的路径,在保证路径最短的同时,显著减少了拓展节点和拐角。实验结果表明,与传统的JPS算法相比,所提算法能缩短路径长度并减少拐角数量,同时拓展节点数量平均减少19%,搜索速度平均提升21.8%。
基金supported by the National Natural Science Foundation of China(11571074,61170308)the Natural Science Foundation of Fujian Province(2015J01010)the Major Science Foundation of Fujian Provincial Department of Education(JA14037)
文摘The alternating direction method of multipliers （ADMM for short） is efficient for linearly constrained convex optimization problem. The practicM computationM cost of ADMM depends on the sub-problem solvers. The proximal point algorithm is a common sub-problem-solver. However, the proximal parameter is sensitive in the proximM ADMM. In this paper, we propose a homotopy-based proximal linearized ADMM, in which a homotopy method is used to soNe the sub-problems at each iteration. Under some suitable conditions, the global convergence and the convergence rate of O（1/k） in the worst case of the proposed method are proven. Some preliminary numerical results indicate the validity of the proposed method.
