The classical variational inequality problem with a Lipschitzian and strongly monotone operator on a nonempty closed convex subset in a real Hilbert space is studied. A new three-step relaxed hybrid steepest-descent m...The classical variational inequality problem with a Lipschitzian and strongly monotone operator on a nonempty closed convex subset in a real Hilbert space is studied. A new three-step relaxed hybrid steepest-descent method for this class of variational inequalities is introduced. Strong convergence of this method is established under suitable assumptions imposed on the algorithm parameters.展开更多
In this paper, we consider the generalized variational inequality GVI（F, g, C）, where F and g are mappings from a Hilbert space into itself and C is the fixed point set of a nonexpansive mapping. We propose two iter...In this paper, we consider the generalized variational inequality GVI（F, g, C）, where F and g are mappings from a Hilbert space into itself and C is the fixed point set of a nonexpansive mapping. We propose two iterative algorithms to find approximate solutions of the GVI（F,g, C）. Strong convergence results are established and applications to constrained generalized pseudo-inverse are included.展开更多
The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flo...The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flow around the airfoil. An efficient framework for implementing the coupled solver and optimization in a multicore environment has been implemented for the generation of optimized solutionsmaximizing thrust performance & computational speed.展开更多
在大规模多输入多输出(multiple-input multiple-output,MIMO)系统信号检测中,最小均方误差(minimum mean square error,MMSE)算法可以得到近似最优检测性能,然而该算法需要高维矩阵求逆,其复杂度很高,无法保证信号的实时检测。因此提...在大规模多输入多输出(multiple-input multiple-output,MIMO)系统信号检测中,最小均方误差(minimum mean square error,MMSE)算法可以得到近似最优检测性能,然而该算法需要高维矩阵求逆,其复杂度很高,无法保证信号的实时检测。因此提出一种改进Richardson信号检测方法,利用最速下降法和整体修正法改进Richardson算法性能,最速下降法可以提供更有效地搜索路径,得到不同近似解,并且为了提高求解精度,利用整体修正法对不同近似解进行修正,使算法收敛速度更快,同时将算法复杂度数量级由O(K^(3))降低到O(K^(2))。仿真结果表明,该算法只需3次迭代就可接近MMSE,在降低复杂度的同时提高了误码率性能。展开更多
本文提出一种用于层状介质中重力、地震资料联合反演层速度、层密度及弯曲界面深度的迭代算法。该方法通过引入加权最小平方目标泛函,将层状介质中的重力、地震资料联合反演问题转化成具体的优化问题。为了得到反问题的最优解,文中系统...本文提出一种用于层状介质中重力、地震资料联合反演层速度、层密度及弯曲界面深度的迭代算法。该方法通过引入加权最小平方目标泛函,将层状介质中的重力、地震资料联合反演问题转化成具体的优化问题。为了得到反问题的最优解,文中系统地研究了层状介质中双摄动处理技术,以及层状介质中波场摄动的一阶 Born 近似解与理论重力异常摄动解。并应用 Tarantola 的反演理论,导出了梯度算子的计算公式。然后应用最速下降法给出了求取最优解的具体算法,得到了一种类似于地震偏移与空间更投影的迭代反演方法。对理论模型进行重力、地震联合反演的结果表明,该方法不仅可碱少未知参数的个数,提高反演的收敛速度,而且可减少反演的不适定性,不失为一种可行的多参数反演方法。展开更多
基金Project supported by the Key Science Foundation of Education Department of Sichuan Province of China (No.2003A081)Sichuan Province Leading Academic Discipline Project (No.SZD0406)
文摘The classical variational inequality problem with a Lipschitzian and strongly monotone operator on a nonempty closed convex subset in a real Hilbert space is studied. A new three-step relaxed hybrid steepest-descent method for this class of variational inequalities is introduced. Strong convergence of this method is established under suitable assumptions imposed on the algorithm parameters.
基金Acknowledgment： This work was partly supported by the National Natural Science Foundation of China（60672150） and Science and Technology Planning Project of Shenzhen, China （szkj0706）.
文摘In this paper, we consider the generalized variational inequality GVI（F, g, C）, where F and g are mappings from a Hilbert space into itself and C is the fixed point set of a nonexpansive mapping. We propose two iterative algorithms to find approximate solutions of the GVI（F,g, C）. Strong convergence results are established and applications to constrained generalized pseudo-inverse are included.
文摘The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flow around the airfoil. An efficient framework for implementing the coupled solver and optimization in a multicore environment has been implemented for the generation of optimized solutionsmaximizing thrust performance & computational speed.
文摘在大规模多输入多输出(multiple-input multiple-output,MIMO)系统信号检测中,最小均方误差(minimum mean square error,MMSE)算法可以得到近似最优检测性能,然而该算法需要高维矩阵求逆,其复杂度很高,无法保证信号的实时检测。因此提出一种改进Richardson信号检测方法,利用最速下降法和整体修正法改进Richardson算法性能,最速下降法可以提供更有效地搜索路径,得到不同近似解,并且为了提高求解精度,利用整体修正法对不同近似解进行修正,使算法收敛速度更快,同时将算法复杂度数量级由O(K^(3))降低到O(K^(2))。仿真结果表明,该算法只需3次迭代就可接近MMSE,在降低复杂度的同时提高了误码率性能。
文摘本文提出一种用于层状介质中重力、地震资料联合反演层速度、层密度及弯曲界面深度的迭代算法。该方法通过引入加权最小平方目标泛函,将层状介质中的重力、地震资料联合反演问题转化成具体的优化问题。为了得到反问题的最优解,文中系统地研究了层状介质中双摄动处理技术,以及层状介质中波场摄动的一阶 Born 近似解与理论重力异常摄动解。并应用 Tarantola 的反演理论,导出了梯度算子的计算公式。然后应用最速下降法给出了求取最优解的具体算法,得到了一种类似于地震偏移与空间更投影的迭代反演方法。对理论模型进行重力、地震联合反演的结果表明,该方法不仅可碱少未知参数的个数,提高反演的收敛速度,而且可减少反演的不适定性,不失为一种可行的多参数反演方法。
