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Adaptive optimization methodology based on Kriging modeling and a trust region method 被引量:14
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作者 Chunna LI Qifeng PAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第2期281-295,共15页
Surrogate-Based Optimization(SBO) is becoming increasingly popular since it can remarkably reduce the computational cost for design optimizations based on high-fidelity and expensive numerical analyses. However, for c... Surrogate-Based Optimization(SBO) is becoming increasingly popular since it can remarkably reduce the computational cost for design optimizations based on high-fidelity and expensive numerical analyses. However, for complicated optimization problems with a large design space, many design variables, and strong nonlinearity, SBO converges slowly and shows imperfection in local exploitation. This paper proposes a trust region method within the framework of an SBO process based on the Kriging model. In each refinement cycle, new samples are selected by a certain design of experiment method within a variable design space, which is sequentially updated by the trust region method. A multi-dimensional trust-region radius is proposed to improve the adaptability of the developed methodology. Further, the scale factor and the limit factor of the trust region are studied to evaluate their effects on the optimization process. Thereafter, different SBO methods using error-based exploration, prediction-based exploitation, refinement based on the expected improvement function, a hybrid refinement strategy, and the developed trust-regionbased refinement are utilized in four analytical tests. Further, the developed optimization methodology is employed in the drag minimization of an RAE2822 airfoil. Results indicate that it has better robustness and local exploitation capability in comparison with those of other SBO 展开更多
关键词 AIRFOIL Design OPTIMIZATION KRIGING model Surrogate-based OPTIMIZATION trust-REGION method
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A Nonmonotone Trust Region Method for Solving Symmetric Nonlinear Equations 被引量:3
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作者 YUAN Gong-lin WEI Zeng-xin LU Xi-wen 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期574-584,共11页
A trust region method combining with nonmonotone technique is proposed tor solving symmetric nonlinear equations. The global convergence of the given method will be established under suitable conditions. Numerical res... A trust region method combining with nonmonotone technique is proposed tor solving symmetric nonlinear equations. The global convergence of the given method will be established under suitable conditions. Numerical results show that the method is interesting for the given problems. 展开更多
关键词 trust region method nonlinear equations nonmonotone technique
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A GLOBALLY AND SUPERLINEARLY CONVERGENT TRUST REGION METHOD FOR LC^1 OPTIMIZATION PROBLEMS 被引量:1
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作者 Zhang Liping Lai Yanlian Institute of Applied Mathematics,Academia Sinica,Beijing 100080. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期72-80,共9页
A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assum... A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assumptions. 展开更多
关键词 LC 1 optimization problem global and superlinear convergence trust region method.
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A TRUST REGION METHOD WITH A CONIC MODEL FOR NONLINEARLY CONSTRAINED OPTIMIZATION 被引量:1
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作者 Wang Chengjing 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第3期263-275,共13页
Trust region methods are powerful and effective optimization methods. The conic model method is a new type of method with more information available at each iteration than standard quadratic-based methods. The adva... Trust region methods are powerful and effective optimization methods. The conic model method is a new type of method with more information available at each iteration than standard quadratic-based methods. The advantages of the above two methods can be combined to form a more powerful method for constrained optimization. The trust region subproblem of our method is to minimize a conic function subject to the linearized constraints and trust region bound. At the same time, the new algorithm still possesses robust global properties. The global convergence of the new algorithm under standard conditions is established. 展开更多
关键词 trust region method conic model constrained optimization nonlinear programming.
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Adaptive Conic Trust-Region Method for Nonlinear Least Squares Problems 被引量:3
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作者 Yang Yang Sun Wenyu 《南京师大学报(自然科学版)》 CAS CSCD 北大核心 2007年第1期13-21,共9页
关键词 非线性最小二乘问题 自适应锥模型 算法
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A TRUST REGION METHOD FOR MICROWAVE TOMOGRAPHY 被引量:1
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作者 Gong Xing (Dept. of Biomedical Engineering, Zhejiang University, Hangzhou 310027) 《Journal of Electronics(China)》 2001年第2期181-184,共4页
A trust region method is proposed to solve the problem of microwave tomography,which is very difficult to be solved for its ill-posedness and nonlinearity. Compared with the Levenberg-Marquardt method, this method int... A trust region method is proposed to solve the problem of microwave tomography,which is very difficult to be solved for its ill-posedness and nonlinearity. Compared with the Levenberg-Marquardt method, this method introduces more a priori knowledge and might obtain better results, though the two methods are equal in some cases. 展开更多
关键词 MICROWAVE TOMOGRAPHY IMAGE RECONSTRUCTION trust REGION method
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A New Nonmonotone Adaptive Trust Region Method 被引量:1
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作者 Yang Zhang Quanming Ji Qinghua Zhou 《Journal of Applied Mathematics and Physics》 2021年第12期3102-3114,共13页
The trust region method plays an important role in solving optimization problems. In this paper, we propose a new nonmonotone adaptive trust region method for solving unconstrained optimization problems. Actually, we ... The trust region method plays an important role in solving optimization problems. In this paper, we propose a new nonmonotone adaptive trust region method for solving unconstrained optimization problems. Actually, we combine a popular nonmonotone technique with an adaptive trust region algorithm. The new ratio to adjusting the next trust region radius is different from the ratio in the traditional trust region methods. Under some appropriate conditions, we show that the new algorithm has good global convergence and superlinear convergence. 展开更多
关键词 Unconstrained Optimization trust Region method Nonmonotone Technique Global Convergence Superlinear Convergence
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A FILTER-TRUST-REGION METHOD FOR LC^1 UNCONSTRAINED OPTIMIZATION AND ITS GLOBAL CONVERGENCE 被引量:1
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作者 ZhenghaoYang Wenyu Sun Chuangyin Dang 《Analysis in Theory and Applications》 2008年第1期55-66,共12页
In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorith... In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorithm under reasonable assumptions. 展开更多
关键词 nonsmooth optimization filter method trust region algorithm global conver- gence LC1 optimization
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Projected gradient trust-region method for solving nonlinear systems with convex constraints
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作者 JIA Chun-xia ZHU De-tong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第1期57-69,共13页
In this paper, a projected gradient trust region algorithm for solving nonlinear equality systems with convex constraints is considered. The global convergence results are developed in a very general setting of comput... In this paper, a projected gradient trust region algorithm for solving nonlinear equality systems with convex constraints is considered. The global convergence results are developed in a very general setting of computing trial directions by this method combining with the line search technique. Close to the solution set this method is locally Q-superlinearly convergent under an error bound assumption which is much weaker than the standard nonsingularity condition. 展开更多
关键词 Nonlinear equation trust region method projected gradient local error bound.
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A CLASS OF TRUST REGION METHODS FOR LINEAR INEQUALITY CONSTRAINED OPTIMIZATION AND ITS THEORY ANALYSIS:I.ALGORITHM AND GLOBAL CONVERGENCEXIU NAIHUA
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作者 XIU NAIHUA 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第3期287-296,共10页
A class of trust region methods for solving linear inequality constrained problems is proposed in this paper. It is shown that the algorithm is of global convergence.The algorithm uses a version of the two-sided proje... A class of trust region methods for solving linear inequality constrained problems is proposed in this paper. It is shown that the algorithm is of global convergence.The algorithm uses a version of the two-sided projection and the strategy of the unconstrained trust region methods. It keeps the good convergence properties of the unconstrained case and has the merits of the projection method. In some sense, our algorithm can be regarded as an extension and improvement of the projected type algorithm. 展开更多
关键词 Linear inequality constrained optimization trust region method global convergence
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A NONMONOTONE TRUST REGION METHOD FOR NONLINEAR LEAST SQUARES PROBLEMS
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作者 邓乃扬 肖奕 +1 位作者 周方俊 吴育华 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1994年第1期33-53,共21页
In this paper we present a nonmonotone trust region method for nonlinear least squares problems with zero-residual and prove its convergence properties. The extensive numerical results are reported which show that the... In this paper we present a nonmonotone trust region method for nonlinear least squares problems with zero-residual and prove its convergence properties. The extensive numerical results are reported which show that the nonmonotone trust region method is generally superior to the usual trust region method. 展开更多
关键词 trust REGION method NONLINEAR least SQUARES NONMONOTONE method.
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A Non-Monotone Trust Region Method with Non-Monotone Wolfe-Type Line Search Strategy for Unconstrained Optimization
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作者 Changyuan Li Qinghua Zhou Xiao Wu 《Journal of Applied Mathematics and Physics》 2015年第6期707-712,共6页
In this paper, we propose and analyze a non-monotone trust region method with non-monotone line search strategy for unconstrained optimization problems. Unlike the traditional non-monotone trust region method, our alg... In this paper, we propose and analyze a non-monotone trust region method with non-monotone line search strategy for unconstrained optimization problems. Unlike the traditional non-monotone trust region method, our algorithm utilizes non-monotone Wolfe line search to get the next point if a trial step is not adopted. Thus, it can reduce the number of solving sub-problems. Theoretical analysis shows that the new proposed method has a global convergence under some mild conditions. 展开更多
关键词 UNCONSTRAINED Optimization Non-Monotone trust Region method Non-Monotone Line Search Global Convergence
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“亡羊补牢”如何“力挽狂澜”?——财务重述信任修复策略对投资者决策的影响机制研究
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作者 李冬伟 方俊 《管理现代化》 北大核心 2025年第5期64-72,共9页
在财务重述行为频发的背景下,企业采取恰当信任修复策略对企业发展至关重要。但是如何选择合适的披露策略与披露方式,从而修复信任感知仍存在疑问。通过两项情景模拟实验,分析了财务重述信任修复策略以及其披露方式对投资者决策的影响... 在财务重述行为频发的背景下,企业采取恰当信任修复策略对企业发展至关重要。但是如何选择合适的披露策略与披露方式,从而修复信任感知仍存在疑问。通过两项情景模拟实验,分析了财务重述信任修复策略以及其披露方式对投资者决策的影响及内在机理。研究表明,企业主动采取信任修复策略能够引发投资者的投资意愿,约束型策略相较于展示型策略更能引导投资者产生积极的投资决策;信任感知在信任修复策略与投资者决策中发挥中介作用;信息披露方式发挥调节作用,并且信任感知发挥了中介作用。本研究拓展了财务重述信任修复策略领域的研究,也为财务重述企业提高信任修复策略有效性、政府监管部门工作以及投资者理性投资提供了管理启示。 展开更多
关键词 财务重述 信任修复策略 信息披露方式 投资者决策 投资者信任感知
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CONVERGENCE PROPERTIES OF IMPROVED SECANT METHODS WITH TRUST REGION MULTIPLIER
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作者 Zhu DetongDept. of Math.,Shanghai Normal Univ.,Shanghai 2 0 0 2 34 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第2期225-238,共14页
The secant methods discussed by Fontecilla (in 1988) are considerably revised through employing a trust region multiplier strategy and introducing a nondifferentiable merit function. In this paper the secant methods a... The secant methods discussed by Fontecilla (in 1988) are considerably revised through employing a trust region multiplier strategy and introducing a nondifferentiable merit function. In this paper the secant methods are also improved by adding a dogleg typed movement which allows to overcome a phenomena similar to the Maratos effect. Furthermore, these algorithms are analyzed and global convergence theorems as well as local superlinear convergence rate are proved. 展开更多
关键词 Secant methods contrained optimization trust region multiplier exact merit function.
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面向造纸生产系统非线性多维度问题的求解器设计与应用
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作者 李康昊 陈浩洲 +2 位作者 张洁 韩育林 满奕 《中国造纸》 北大核心 2025年第2期8-15,共8页
造纸工业智能化转型过程涉及大量高维数学模型的动态、实时求解问题。由于造纸生产系统的非线性、多维度和不确定性等特点,导致描述造纸生产的数学模型往往由庞大的方程组构成,同时,因造纸过程生产波动较大、生产切换频繁,需对复杂模型... 造纸工业智能化转型过程涉及大量高维数学模型的动态、实时求解问题。由于造纸生产系统的非线性、多维度和不确定性等特点,导致描述造纸生产的数学模型往往由庞大的方程组构成,同时,因造纸过程生产波动较大、生产切换频繁,需对复杂模型组进行频繁、高效的求解,以满足动态生产优化的需求。研究面向造纸模型求解问题的求解器,是解决该问题的关键。本研究针对造纸生产模型非线性多维度求解的特点,基于信赖域内点法和TikTak多起点优化算法,设计了面向非线性多维度造纸生产系统的全局优化求解器,实现了对复杂生产约束和不确定初始条件的高效求解。结果表明,本求解器在造纸干燥部优化案例中以100%的成功率找到全局最优解,单个案例平均求解时间为0.81 s,表现出高度稳健性。此外,在造纸能量系统优化案例中成功求解并节约了59.7%的计算资源和9.29%的计算时间。 展开更多
关键词 信赖域内点法 多起点优化算法 求解器 非线性优化
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基于神经网络的驻波加速结构单腔频率计算方法研究
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作者 赵静远 杨誉 +4 位作者 李丹阳 秦成 雷瀚 杨京鹤 朱志斌 《原子能科学技术》 北大核心 2025年第S2期489-497,共9页
电子直线加速器中加速结构的调谐至关重要,其关键在于准确获得各单腔频率。针对驻波加速结构,本文提出了一种结合神经网络与信赖域优化算法的单腔频率计算方法,利用腔链的反射系数可计算各单腔频率值。通过对S波段、C波段加速腔链进行... 电子直线加速器中加速结构的调谐至关重要,其关键在于准确获得各单腔频率。针对驻波加速结构,本文提出了一种结合神经网络与信赖域优化算法的单腔频率计算方法,利用腔链的反射系数可计算各单腔频率值。通过对S波段、C波段加速腔链进行单腔和整管仿真,验证了该方法的可行性。之后对实际加速腔链开展了单腔及整管测试,该方法得到的大部分单腔频率计算值与实测值的偏差均在1 MHz以下,对于加速结构的测试调配可以起到较好的指导作用。 展开更多
关键词 驻波加速结构 调谐方法 卷积神经网络 信赖域
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考虑SOP与主动电压控制的有源配网两阶段随机规划 被引量:1
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作者 刘艾旺 张明明 +4 位作者 姚宝明 胡程平 姜振宇 张超 施云辉 《电子科技》 2025年第5期1-7,21,共8页
为解决配网对新能源承载力不足的问题,文中提出了一种考虑软开关(Soft Open Point,SOP)和负荷主动电压控制的联合规划模型和求解方法。建立应用于配电网规划的SOP数学模型,分别针对多项式形式和指数形式的负荷电压特性建立线性化模型。... 为解决配网对新能源承载力不足的问题,文中提出了一种考虑软开关(Soft Open Point,SOP)和负荷主动电压控制的联合规划模型和求解方法。建立应用于配电网规划的SOP数学模型,分别针对多项式形式和指数形式的负荷电压特性建立线性化模型。以分布式新能源承载力、投资成本和运行成本为目标,建立有源配网两阶段随机二阶锥规划模型,对SOP、电容器组以及分布式新能源等设备的选址定容及其日内运行策略做出决策。考虑新能源、负荷和能源价格的不确定性,提出了基于K均值的场景聚类方法,提出了基于信赖域法的Benders分解算法来求解所提模型。通过改进51节点系统验证了所提模型的有效性和正确性,并分析了SOP与主动电压控制对新能源承载力的影响。 展开更多
关键词 软开关 主动电压控制 负荷电压特性 随机规划 光伏承载力 二阶锥规划 信赖域 Benders分解
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大功率牵引整流机组用多端口直流变换器模型预测控制
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作者 舒立三 杨浩 +1 位作者 赵鹤璇 董政 《科学技术与工程》 北大核心 2025年第25期10719-10725,共7页
大功率牵引整流机组的高压直流母线存在较大电压波动,严重影响了系统的供电质量和稳定性。为满足系统电压波动抑制及负载宽范围调节的要求,针对中间级直流变换系统,以三有源桥变换器为研究对象,提出了一种基于信赖域狗腿法的模型预测控... 大功率牵引整流机组的高压直流母线存在较大电压波动,严重影响了系统的供电质量和稳定性。为满足系统电压波动抑制及负载宽范围调节的要求,针对中间级直流变换系统,以三有源桥变换器为研究对象,提出了一种基于信赖域狗腿法的模型预测控制策略。首先介绍了三有源桥变换器的工作原理及端口耦合机理,其次,建立了三有源桥变换器预测模型并构建了相应的代价函数;然后针对三有源桥变换器代价函数在线求解困难的问题,采用信赖域狗腿寻优算法实现代价函数的最小化;最后,在实验室样机上验证了所提策略的有效性。实验结果表明:与传统比例积分控制相比,所提方法有效抑制了三有源桥变换器的电压波动,提升了系统的动态性能及负载调节性能,同时实现了端口解耦。 展开更多
关键词 牵引供电 三有源桥变换器 模型预测控制 信赖域法
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求解信赖域子问题的Newton-GMRES方法
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作者 殷婉如 芮绍平 《青岛大学学报(自然科学版)》 2025年第2期4-9,共6页
为求解信赖域子问题,通过构造新的光滑函数将子问题的互补模型转化成等价的方程组,将非精确牛顿法与GMRES算法相结合,得到求解信赖域子问题的Newton-GMRES算法,在一定条件下证明该算法的全局收敛性与适定性。数值实验结果表明,该算法可... 为求解信赖域子问题,通过构造新的光滑函数将子问题的互补模型转化成等价的方程组,将非精确牛顿法与GMRES算法相结合,得到求解信赖域子问题的Newton-GMRES算法,在一定条件下证明该算法的全局收敛性与适定性。数值实验结果表明,该算法可行有效。 展开更多
关键词 信赖域子问题 非精确牛顿法 光滑函数 全局收敛
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投票行为加权的间接信任评估方法TrustRank
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作者 席娜 徐术力 《科技广场》 2013年第9期15-18,共4页
本文提出了一种基于投票行为加权的间接信任评估方法 TrustRank,通过对参与投票节点及其行为的量化分析,根据节点的不同权重和可信任度,计算出相应节点的间接信任等级,并给出了TrustRank方法的数学表达。
关键词 间接信任 评估方法 权重 量化分析
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