In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality co...In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality constrained mini-max optimization problem into unconstrained optimization problem. A trust-region method is a well-accepted technique in constrained optimization to assure global convergence and is more robust when they deal with rounding errors. One of the advantages of trust-region method is that it does not require the objective function of the model to be convex. A global convergence analysis for the proposed algorithm is presented under some conditions. To show the efficiency of the algorithm numerical results for a number of test problems are reported.展开更多
以高压直流输电系统快速可控为出发点,采用极大极小值原理和改进粒子群优化算法相结合的新方法,针对向家坝—上海±800 k V特高压直流输电系统送端可能发生的次同步振荡(sub-synchronous oscillation,SSO)问题,建立一种基于比例积...以高压直流输电系统快速可控为出发点,采用极大极小值原理和改进粒子群优化算法相结合的新方法,针对向家坝—上海±800 k V特高压直流输电系统送端可能发生的次同步振荡(sub-synchronous oscillation,SSO)问题,建立一种基于比例积分微分控制的UHVDC附加次同步振荡阻尼控制器(subsynchronous oscillation damping controller,SSDC)模型。对不同方式的时域仿真结果表明,该SSDC控制器能够有效抑制交直流互联电网送端系统汽轮机组的轴系扭振,可在相当大范围内保证系统的SSO稳定性,具有较强的鲁棒性。展开更多
【目的】评价中国栽培大豆微核心种质的群体结构和遗传多样性水平,为拓宽大豆遗传基础、发掘优异基因、改良大豆品种提供理论依据。【方法】利用大豆20个连锁群上的100个SSR位点,对来自全国28个省补充完善的248份栽培大豆微核心种质进行...【目的】评价中国栽培大豆微核心种质的群体结构和遗传多样性水平,为拓宽大豆遗传基础、发掘优异基因、改良大豆品种提供理论依据。【方法】利用大豆20个连锁群上的100个SSR位点,对来自全国28个省补充完善的248份栽培大豆微核心种质进行SSR遗传多样性及群体结构分析;采用PowerMarker Version 3.25软件统计等位变异数、平均等位变异数、多态性信息量(PIC值)及亚群特有等位变异数等参数;基于遗传距离建立了栽培大豆微核心种质的无根Neighbor-Joining树;用Structure2.2软件对微核心种质的群体结构进行评价。【结果】100个SSR位点在248份材料中共检测出等位变异1460个,每个位点变异范围为2—33个,平均为14.6个,每个位点PIC值变异范围为0.158—0.932,平均为0.743。基于模型的群体结构分析显示,依据LnP(D)无法判断最佳K值(群组数),但通过计算系数ΔK发现,K=3为微核心种质的最佳群体结构。结合种质的生态类型及品种类型分析发现,地理来源相同的种质具有聚在一起的倾向,但来源相同的种质也有分在不同组的情况。不同生态类型及品种类型间均存在较多的互补等位变异和特有等位变异。【结论】中国栽培大豆微核心种质具有丰富的遗传多样性,可以用来拓宽大豆品种遗传基础;不同生态类型及品种类型间存在较多的互补及特有等位变异,是种质创新及品种改良的物质基础;栽培大豆微核心种质存在明显的群体结构,为微核心种质在育种中的直接或间接利用提供了理论依据。展开更多
本文研究带不确定方差乘性和加性噪声和带状态相依及噪声相依乘性噪声的多传感器系统鲁棒加权融合估计问题.通过引入虚拟噪声补偿乘性噪声的不确定性,将原系统化为带确定参数和不确定加性噪声方差的系统,进而利用Lyapunov方程方法提出...本文研究带不确定方差乘性和加性噪声和带状态相依及噪声相依乘性噪声的多传感器系统鲁棒加权融合估计问题.通过引入虚拟噪声补偿乘性噪声的不确定性,将原系统化为带确定参数和不确定加性噪声方差的系统,进而利用Lyapunov方程方法提出在统一框架下的按对角阵加权融合极大极小鲁棒稳态Kalman估值器(预报器、滤波器和平滑器),其中基于预报器设计滤波器和平滑器,并给出每个融合器的实际估值误差方差的最小上界.证明了融合器的鲁棒精度高于每个局部估值器的鲁棒精度.应用于不间断电源(uninterruptible power system,UPS)系统鲁棒融合滤波的仿真例子说明了所提结果的正确性和有效性.展开更多
In this paper, we study the multiplicity results of positive solutions for a class of quasi-linear elliptic equations involving critical Sobolev exponent. With the help of Nehari manifold and a mini-max principle, we ...In this paper, we study the multiplicity results of positive solutions for a class of quasi-linear elliptic equations involving critical Sobolev exponent. With the help of Nehari manifold and a mini-max principle, we prove that problem admits at least two or three positive solutions under different conditions.展开更多
文摘In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality constrained mini-max optimization problem into unconstrained optimization problem. A trust-region method is a well-accepted technique in constrained optimization to assure global convergence and is more robust when they deal with rounding errors. One of the advantages of trust-region method is that it does not require the objective function of the model to be convex. A global convergence analysis for the proposed algorithm is presented under some conditions. To show the efficiency of the algorithm numerical results for a number of test problems are reported.
文摘【目的】评价中国栽培大豆微核心种质的群体结构和遗传多样性水平,为拓宽大豆遗传基础、发掘优异基因、改良大豆品种提供理论依据。【方法】利用大豆20个连锁群上的100个SSR位点,对来自全国28个省补充完善的248份栽培大豆微核心种质进行SSR遗传多样性及群体结构分析;采用PowerMarker Version 3.25软件统计等位变异数、平均等位变异数、多态性信息量(PIC值)及亚群特有等位变异数等参数;基于遗传距离建立了栽培大豆微核心种质的无根Neighbor-Joining树;用Structure2.2软件对微核心种质的群体结构进行评价。【结果】100个SSR位点在248份材料中共检测出等位变异1460个,每个位点变异范围为2—33个,平均为14.6个,每个位点PIC值变异范围为0.158—0.932,平均为0.743。基于模型的群体结构分析显示,依据LnP(D)无法判断最佳K值(群组数),但通过计算系数ΔK发现,K=3为微核心种质的最佳群体结构。结合种质的生态类型及品种类型分析发现,地理来源相同的种质具有聚在一起的倾向,但来源相同的种质也有分在不同组的情况。不同生态类型及品种类型间均存在较多的互补等位变异和特有等位变异。【结论】中国栽培大豆微核心种质具有丰富的遗传多样性,可以用来拓宽大豆品种遗传基础;不同生态类型及品种类型间存在较多的互补及特有等位变异,是种质创新及品种改良的物质基础;栽培大豆微核心种质存在明显的群体结构,为微核心种质在育种中的直接或间接利用提供了理论依据。
文摘本文研究带不确定方差乘性和加性噪声和带状态相依及噪声相依乘性噪声的多传感器系统鲁棒加权融合估计问题.通过引入虚拟噪声补偿乘性噪声的不确定性,将原系统化为带确定参数和不确定加性噪声方差的系统,进而利用Lyapunov方程方法提出在统一框架下的按对角阵加权融合极大极小鲁棒稳态Kalman估值器(预报器、滤波器和平滑器),其中基于预报器设计滤波器和平滑器,并给出每个融合器的实际估值误差方差的最小上界.证明了融合器的鲁棒精度高于每个局部估值器的鲁棒精度.应用于不间断电源(uninterruptible power system,UPS)系统鲁棒融合滤波的仿真例子说明了所提结果的正确性和有效性.
文摘In this paper, we study the multiplicity results of positive solutions for a class of quasi-linear elliptic equations involving critical Sobolev exponent. With the help of Nehari manifold and a mini-max principle, we prove that problem admits at least two or three positive solutions under different conditions.
