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Ridge estimation iterative solution of ill-posed mixed additive and multiplicative random error model with equality constraints 被引量:3
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作者 Leyang Wang Tao Chen 《Geodesy and Geodynamics》 CSCD 2021年第5期336-346,共11页
The reasonable prior information between the parameters in the adjustment processing can significantly improve the precision of the parameter solution. Based on the principle of equality constraints, we establish the ... The reasonable prior information between the parameters in the adjustment processing can significantly improve the precision of the parameter solution. Based on the principle of equality constraints, we establish the mixed additive and multiplicative random error model with equality constraints and derive the weighted least squares iterative solution of the model. In addition, aiming at the ill-posed problem of the coefficient matrix, we also propose the ridge estimation iterative solution of ill-posed mixed additive and multiplicative random error model with equality constraints based on the principle of ridge estimation method and derive the U-curve method to determine the ridge parameter. The experimental results show that the weighted least squares iterative solution can obtain more reasonable parameter estimation and precision information than existing solutions, verifying the feasibility of applying the equality constraints to the mixed additive and multiplicative random error model. Furthermore, the ridge estimation iterative solution can obtain more accurate parameter estimation and precision information than the weighted least squares iterative solution. 展开更多
关键词 Ill-posed problem Mixed additive and multiplicative random error model equality constraints Weighted least squares Ridge estimation method U-curve method
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Power System State Estimation Solution With Zero Injection Constraints Using Modified Newton Method and Fast Decoupled Method in Polar Coordinate 被引量:13
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作者 GUO Ye ZHANG Boming WU Wenchuag SUN Hongbin 《中国电机工程学报》 EI CSCD 北大核心 2012年第22期I0015-I0015,11,共1页
如何保证零注入节点的注入功率在状态估计结果中严格为0是电力系统状态估计研究中的重要问题。在直角坐标下,由于零注入约束为线性约束,可使用修正牛顿法来有效地解决这一问题。因此,借鉴直角坐标下修正牛顿法的思路,提出了极坐标下的... 如何保证零注入节点的注入功率在状态估计结果中严格为0是电力系统状态估计研究中的重要问题。在直角坐标下,由于零注入约束为线性约束,可使用修正牛顿法来有效地解决这一问题。因此,借鉴直角坐标下修正牛顿法的思路,提出了极坐标下的修正牛顿法和修正快速解耦估计。这些方法的计算流程与传统的极坐标下的牛顿法和快速解耦估计非常相似,计算速度与大权重法相当,同时能够保证零注入约束严格满足。仿真结果验证了所得结论。 展开更多
关键词 状态估计模型 电力系统 解耦方法 注射 极坐标 牛顿法 基尔霍夫电流定律 电压变压器
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GLOBAL CONVERGENCE OF A TRUST REGION ALGORITHM USING INEXACT GRADIENT FOR EQUALITY-CONSTRAINED OPTIMIZATION 被引量:1
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作者 童小娇 周叔子 《Acta Mathematica Scientia》 SCIE CSCD 2000年第3期365-373,共9页
A trust-region algorithm is presented for a nonlinear optimization problem of equality-constraints. The characterization of the algorithm is using inexact gradient information. Global convergence results are demonstra... A trust-region algorithm is presented for a nonlinear optimization problem of equality-constraints. The characterization of the algorithm is using inexact gradient information. Global convergence results are demonstrated where the gradient values are obeyed a simple relative error condition. 展开更多
关键词 equality constraints trust region method inexact gradient global convergence
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A trust region algorithm for optimization with nonlinear equality and linear inequality constraints 被引量:1
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作者 陈中文 韩继业 《Science China Mathematics》 SCIE 1996年第8期799-806,共8页
A new algorithm of trust region type is presented to minimize a differentiable function ofmany variables with nonlinear equality and linear inequality constraints. Under the milder conditions, theglobal convergence of... A new algorithm of trust region type is presented to minimize a differentiable function ofmany variables with nonlinear equality and linear inequality constraints. Under the milder conditions, theglobal convergence of the main algorithm is proved. Moreover, since any nonlinear inequality constraint can beconverted into an equation by introducing a slack variable, the trust region method can be used in solving general nonlinear programming problems. 展开更多
关键词 TRUST REGIONS global convergence nonlinear equality constraints linear inequality constraints.
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Sliding polynomial modeling with equality constraints
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作者 LIU Ye TANG GeShi +2 位作者 YU AnXi ZHU JuBo LIANG DianNong 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第7期1818-1824,共7页
Sliding polynomial modeling has undergone considerable development and has been widely applied to dynamic modeling. One focus of the polynomial model is to make efficient use of prior information, which can also be ca... Sliding polynomial modeling has undergone considerable development and has been widely applied to dynamic modeling. One focus of the polynomial model is to make efficient use of prior information, which can also be called additional or constrained information. Considering the fact that much additional information can be translated to equality constraints, we develop a new two-stage approach for sliding polynomial modeling with equality constraints. To maintain its compatibility with the polyno-mial model without this constraint, only a simple adjustment based on the constraint equation is involved in the algorithm. The approach is easy to implement and is superior in observability, convergence and accuracy. The results of a simulation study of spacecraft tracking are provided to confirm the theoretical development. As no special hypotheses are required, the approach presented here can be widely applied to dynamic modeling for nonlinear systems with equality constraints. Furthermore, per-formance predictions for other dynamic models can also draw lessons from this approach. 展开更多
关键词 SLIDinG POLYNOMIAL equality CONSTRAinT ITERATION TARGET tracking
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铁路直线轨道约束的动态精密单点定位
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作者 凌超 《铁道勘测与设计》 2025年第1期13-18,共6页
常规的精密单点定位(Precise Point Positioning,PPP)算法中尚未考虑附加先验信息约束的方法,当系统存在固有的先验信息时,不加以利用可能会导致信息的浪费。对此,本文重点研究了车辆直线运动轨迹所存在的约束信息,推导整理了空间直线... 常规的精密单点定位(Precise Point Positioning,PPP)算法中尚未考虑附加先验信息约束的方法,当系统存在固有的先验信息时,不加以利用可能会导致信息的浪费。对此,本文重点研究了车辆直线运动轨迹所存在的约束信息,推导整理了空间直线斜截式约束方程,同时结合等式约束滤波方法中的准确测量法应用到PPP的参数估计过程中,形成附加直线轨迹约束的PPP方法。实验表明:在铁路直线轨道约束实验中,收敛时间最高减少60%,定位精度最高提升14.94%,不同实验结果均表明附加直线轨迹约束能提高PPP定位性能。 展开更多
关键词 精密单点定位 先验约束信息 等式约束 铁路轨道 收敛时间
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顾及位置关系的直线参数整体最小估计算法
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作者 颜晓于 刘宇凡 +1 位作者 鲁子洋 张重阳 《甘肃科学学报》 2025年第1期1-7,15,共8页
针对直线间平行、垂直和斜交的3种位置关系,提出将直线间的位置关系转化为等式约束条件,结合加权整体最小二乘法进行直线拟合。首先,将直线间的3种位置关系表达为直线斜率的关系,对其线性化,得到3种约束模型;其次,根据加权整体最小二乘... 针对直线间平行、垂直和斜交的3种位置关系,提出将直线间的位置关系转化为等式约束条件,结合加权整体最小二乘法进行直线拟合。首先,将直线间的3种位置关系表达为直线斜率的关系,对其线性化,得到3种约束模型;其次,根据加权整体最小二乘准则确定附有等式约束的加权整体最小二乘法平差模型,推导其解算方程,并建立平差算法;最后,针对3种约束模型进行拟合实验。实验结果表明:新算法具有可行性,拟合精度较高,且能确保直线间的平面位置关系正确。 展开更多
关键词 平面位置关系 直线拟合 加权整体最小二乘 等式约束
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A Generalized Gradient Projection Algorithm of Optimization With Nonlinear Constraints
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作者 赖炎连 高自友 贺国平 《Science China Mathematics》 SCIE 1993年第2期170-180,共11页
Although many effective algorithms of the gradient projection type have been given, there exist some problems which are not solved in these algorithms. In this paper, we consider the problem with nonlinear equality an... Although many effective algorithms of the gradient projection type have been given, there exist some problems which are not solved in these algorithms. In this paper, we consider the problem with nonlinear equality and inequality constraints and have given a generalized gradient projection algorithm. The global convergence of the algorithm has been proved and the problems have been solved completely by our algorithm. 展开更多
关键词 optimized problem with inequality and equality constraints gradientprojection method generalized GRADIENT PROJECTION ALGORITHM CONVERGENCE of algorithm.
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Method for solving fully fuzzy linear programming problems using deviation degree measure
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作者 Haifang Cheng Weilai Huang Jianhu Cai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第5期793-799,共7页
A new fully fuzzy linear programming (FFLP) problem with fuzzy equality constraints is discussed. Using deviation degree measures, the FFLP problem is transformed into a crisp 6-parametric linear programming (LP) ... A new fully fuzzy linear programming (FFLP) problem with fuzzy equality constraints is discussed. Using deviation degree measures, the FFLP problem is transformed into a crisp 6-parametric linear programming (LP) problem. Giving the value of deviation degree in each constraint, the 6-fuzzy optimal solution of the FFLP problem can be obtained by solving this LP problem. An algorithm is also proposed to find a balance-fuzzy optimal solution between two goals in conflict: to improve the values of the objective function and to decrease the values of the deviation degrees. A numerical example is solved to illustrate the proposed method. 展开更多
关键词 fully fuzzy linear programming (FFLP) fuzzy equality constraint triangular fuzzy number deviation degree.
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A GLOBALLY CONVERGENT TRUST REGION ALGORITHM FOR OPTIMIZATION WITH GENERAL CONSTRAINTS AND SIMPLE BOUNDS 被引量:3
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作者 陈中文 韩继业 韩乔明 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1999年第4期425-432,共8页
In this paper, we introduce a concept of substationary points and present a new trust region-based method for the optimization problems with general nonlinear equality constraints and simple bounds. Without the linear... In this paper, we introduce a concept of substationary points and present a new trust region-based method for the optimization problems with general nonlinear equality constraints and simple bounds. Without the linear independent assumption on the gradients of the equalitiy constraints, we prove the global convergence results for the main algorithm and indicate that they extend the results on SQP and those on trust region methods for equality constrained optimizstion and for optimization with simple bounds. Moreover, since any nonlinear programming problem can be converted into the standard nonlinear programming by introducing slack variables, the trust region method preseated in this paper can be used for solving general nonlinear programming problems. 展开更多
关键词 Trust region method global convergence nonlinear equality constraints substationary point
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Minimax State Estimator for Uncertain Systems with L_2 Bounded Constraint
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作者 范颖晖 陈善本 张福恩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第2期94-98,共5页
Minimax state estimation is discussed for uncerttain systems with L2 bounded constraint. A dtaity relation-equality is introduced to estimate terminal state variabes x(T) by measurable outputs . hawing a game theory, ... Minimax state estimation is discussed for uncerttain systems with L2 bounded constraint. A dtaity relation-equality is introduced to estimate terminal state variabes x(T) by measurable outputs . hawing a game theory, opti-mal estimation leads to a simple solution. LQL control scheme, is further discussed to make it rational in the actual application. 展开更多
关键词 Minimax state estimation duality relation-equality game theory L_2 bounded constraint
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阶层跨越与共同富裕:居民家庭收入与财富的流动性及其约束
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作者 李静 高楠 戴昕晨 《经济理论与经济管理》 CSSCI 北大核心 2024年第11期71-89,共19页
本文构建多个样本,结合资产视角分析我国低收入居民家庭的阶层流动性及其向上流动的约束。研究发现,近年来我国低收入居民家庭的阶层流动水平趋势向好,有近半概率实现向上流动,相对流动水平与绝对流动水平不断提高,在长期中可以获得更... 本文构建多个样本,结合资产视角分析我国低收入居民家庭的阶层流动性及其向上流动的约束。研究发现,近年来我国低收入居民家庭的阶层流动水平趋势向好,有近半概率实现向上流动,相对流动水平与绝对流动水平不断提高,在长期中可以获得更高的财富地位;居民家庭收入的阶层流动水平整体高于家庭资产的阶层流动水平,可见居民家庭在收入中有更大的可能实现阶层跨越。此外,低收入居民家庭相对流动水平良好,这有效支撑其流动进入中等收入群体,然而外部优势资源的欠缺使得该群体难以获得更高的财富地位;降低区域间经济资源与教育水平差异是推动低收入居民家庭实现大幅度阶层上升的关键。本文认为,进一步提高低收入居民家庭阶层流动水平、缩减社会收入与财富差距需要积极推动区域间公共资源分配均衡化。 展开更多
关键词 低收入居民家庭 阶层流动性 向上流动约束 公共资源均衡化
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论专业法官会议制度设置的逻辑基础
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作者 顾培东 陈雨 《兰州大学学报(社会科学版)》 CSSCI 北大核心 2024年第5期107-118,共12页
作为法院内部的一项设置,专业法官会议制度具有其历史逻辑、正当性逻辑、功能逻辑以及运作逻辑。从历史逻辑看,专业法官会议制度是在特定司法需求的持续驱动下,由庭务会、审判长联席会议等非正式机制演变而来。从正当性逻辑看,专业法官... 作为法院内部的一项设置,专业法官会议制度具有其历史逻辑、正当性逻辑、功能逻辑以及运作逻辑。从历史逻辑看,专业法官会议制度是在特定司法需求的持续驱动下,由庭务会、审判长联席会议等非正式机制演变而来。从正当性逻辑看,专业法官会议制度的正当性既源于其所形成的实践效用,亦源于我国法院整体本位运行模式、民主集中制组织原则以及集体主义文化传统。从功能逻辑看,专业法官会议制度之所以能发挥一系列功能,在于其推动了行权公开化与平权性制约、司法经验与智慧的共享以及司法共识的形成。从运作逻辑看,技术逻辑、成本逻辑以及控制逻辑共同构成了专业法官会议运行的内在机理。对专业法官会议制度的基础逻辑进行研究,有助于加深对该制度的理解,进一步奠定专业法官会议制度的理论基础。 展开更多
关键词 专业法官会议 法院整体本位 平权性制约 审判资源配置 制度逻辑
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基于储能系统多重约束的一次调频策略
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作者 梁继业 袁至 +2 位作者 王维庆 李骥 范玮 《高电压技术》 EI CAS CSCD 北大核心 2024年第6期2478-2489,共12页
基于荷电状态(state of charge,SOC)控制储能系统参与一次调频时,由于储能系统出力约束条件较为单一,因而限制了储能系统的性能。针对此问题提出一种基于储能系统多重约束的一次调频策略。首先,把通过双层模糊控制方法确定储能系统多时... 基于荷电状态(state of charge,SOC)控制储能系统参与一次调频时,由于储能系统出力约束条件较为单一,因而限制了储能系统的性能。针对此问题提出一种基于储能系统多重约束的一次调频策略。首先,把通过双层模糊控制方法确定储能系统多时间尺度调频死区作为第1重约束条件,避免火电机组与储能电池频繁动作。其次,将SOC作为第2重约束条件,约束因子作为第3重约束条件,基于logistic曲线构建惯性与下垂综合控制模型,约束储能系统出力。最后,通过高精度SOC构建快速均衡函数,缩短SOC均衡时间。通过搭建仿真模型分别在阶跃负荷扰动和连续负荷扰动的工况下验证所提控制策略有效性。 展开更多
关键词 一次调频 多时间尺度 荷电状态 约束因子 快速均衡
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b-距离空间中有限个等式约束下的耦合不动点问题
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作者 贺丹妮 贺飞 《数学杂志》 2024年第2期169-181,共13页
本文研究了b-距离空间中有限个等式约束下的耦合不动点问题.利用数学归纳法,获得了b-距离空间中一类有限个等式约束下的非线性压缩耦合不动点结果,将已有的Banach空间中的结果推广到b-距离空间中.特别地,我们结果中的压缩条件与空间系... 本文研究了b-距离空间中有限个等式约束下的耦合不动点问题.利用数学归纳法,获得了b-距离空间中一类有限个等式约束下的非线性压缩耦合不动点结果,将已有的Banach空间中的结果推广到b-距离空间中.特别地,我们结果中的压缩条件与空间系数无关.作为应用,得到了对称等式约束下的不动点定理,公共耦合不动点定理以及b-距离空间中非线性压缩不动点定理.这些结果可以推出许多已有结果,甚至将一些结果中的部分条件完全去掉. 展开更多
关键词 b-距离空间 耦合不动点 等式约束 非线性压缩
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距离空间中有限个等式约束下的Geraghty型耦合不动点问题
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作者 贺丹妮 贺飞 《内蒙古大学学报(自然科学版)》 CAS 2024年第3期244-252,共9页
在距离空间中建立了一类有限个等式约束下的Geraghty型耦合不动点定理。作为推论,得到了对称等式约束下的不动点定理和公共耦合不动点定理。
关键词 距离空间 耦合不动点 等式约束 Geraghty型不动点定理
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含复杂电源结构省级电力系统电力电量平衡方法
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作者 李程昊 张佳伟 +3 位作者 姚德贵 李晓萌 葛晟 吕泉 《高电压技术》 EI CAS CSCD 北大核心 2024年第3期1100-1110,I0003-I0006,共15页
随着风电、光伏大规模接入电力系统,为计及其出力的不确定性,需要以年为尺度、小时为颗粒度进行电力电量平衡分析。以含复杂电源结构、内部断面限制、外部交直流受电的省级电力系统为对象,提出了一种新的电力电量平衡分析方法。该方法... 随着风电、光伏大规模接入电力系统,为计及其出力的不确定性,需要以年为尺度、小时为颗粒度进行电力电量平衡分析。以含复杂电源结构、内部断面限制、外部交直流受电的省级电力系统为对象,提出了一种新的电力电量平衡分析方法。该方法以日周期进行滚动平衡分析,针对特定日:通过对各分区同类电源进行聚合以简化问题、降低求解规模;通过构建火电开机优化模型以在考虑断面限制下以均衡开机为原则确定各分区火电开机容量;通过合理设计优化调度模型以在满足不同分区同类电源均衡调度、同一分区不同种类电源顺序调用原则下实现电力平衡计算。算例以实际省级电力系统数据为基础,验证了该方法的有效性、合理性、快速性。 展开更多
关键词 电力电量平衡 复杂电源结构 断面约束 电源聚合 逐日滚动 分区均衡 电源顺序调用
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COMPOSITE-STEP LIKE FILTER METHODS FOR EQUALITY CONSTRAINT PROBLEMS 被引量:7
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作者 Pu-yan Nie(LSEC, ICMSEC, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, China) 《Journal of Computational Mathematics》 SCIE EI CSCD 2003年第5期613-624,共12页
In a composite-step approach, a step Sk is computed as the sum of two components Uk and hk. The normal component Vk, which is called the vertical step, aims to improve the linearized feasibility, while the tangential ... In a composite-step approach, a step Sk is computed as the sum of two components Uk and hk. The normal component Vk, which is called the vertical step, aims to improve the linearized feasibility, while the tangential component hk, which is also called horizontal step, concentrates on reducing a model of the merit functions. As a filter method, it reduces both the infeasibility and the objective function. This is the same property of these two methods. In this paper, one concerns the composite-step like filter approach. That is, a step is tangential component hk if the infeasibility is reduced. Or else, Sk is a composite step composed of normal component Uk, and tangential component hk. 展开更多
关键词 Composite-step like approaches Filter methods equality constraints Sequen- tial quadratic programming(SQP) algorithms Normal component Tangential component Convergence.
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A New Method of Moving Asymptotes for Large-scale Linearly Equality-constrained Minimization 被引量:1
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作者 Hai-jun Wang Qin Ni Hao Liu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2011年第2期317-328,共12页
A new method of moving asymptotes for large-scale minimization subject to linear equality constraints is discussed. In this method, linear equality constraints are deleted with null space technique and the descending ... A new method of moving asymptotes for large-scale minimization subject to linear equality constraints is discussed. In this method, linear equality constraints are deleted with null space technique and the descending direction is obtained by solving a convex separable subproblem of moving asymptotes in each iteration. New rules for controlling the asymptotes parameters are designed and the global convergence of the method under some reasonable conditions is established and proved. The numerical results show that the new method may be capable of processing some large scale problems. 展开更多
关键词 method of moving asymptotes trust region linear search large scale linear equality constraints
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等式约束的一类新的光滑精确罚函数
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作者 房明磊 盛雨婷 丁德凤 《安徽理工大学学报(自然科学版)》 CAS 2024年第1期89-95,共7页
目的为了有效地处理含等式、不等式的约束优化问题,追求具有更优性质、更简单形式的罚函数以及高效快速的算法。方法提出了一类新的罚函数,用于解决等式约束优化问题。结果通过证明,得到了新罚函数的性质:光滑性和精确性。同时,可以通... 目的为了有效地处理含等式、不等式的约束优化问题,追求具有更优性质、更简单形式的罚函数以及高效快速的算法。方法提出了一类新的罚函数,用于解决等式约束优化问题。结果通过证明,得到了新罚函数的性质:光滑性和精确性。同时,可以通过适当选择罚参数的值来实现最优解的求解。特别在Mangasarian-Fromovitz(M-F)约束条件下,可以证明当罚参数取得足够大时,无约束优化问题的局部极小点也是原等式约束优化问题的局部极小点。结合提出的罚函数形式,给出了相应的罚函数算法。通过数值实验的结果,可以验证罚函数算法在求解等式约束优化问题上是可行的。结论新提出的罚函数形式具备了更优的性质,可以有效地将等式约束优化问题转化为无约束优化问题,并利用罚函数算法来求解,为约束优化问题提供了一种新的参考方法。 展开更多
关键词 等式约束 罚函数 KKT点 Mangasarian-Fromovitz约束条件
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