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Discontinuous penalty approach with deviation integral for global constrained minimization 被引量:1
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作者 陈柳 姚奕荣 郑权 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第9期1201-1210,共10页
In this paper, we use the discontinuous exact penalty functions to solve the constrained minimization problems with an integral approach. We examine a general form of the constrained deviation integral and its analyti... In this paper, we use the discontinuous exact penalty functions to solve the constrained minimization problems with an integral approach. We examine a general form of the constrained deviation integral and its analytical properties. The optimality conditions of the penalized minimization problems are proven. To implement the al- gorithm, the cross-entropy method and the importance sampling are used based on the Monte-Carlo technique. Numerical tests show the effectiveness of the proposed algorithm. 展开更多
关键词 global optimization constrained problems deviation integral cross-entropy method
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MODIFIED INTEGRAL-LEVEL SET METHOD FOR THE CONSTRAINED SOLVING GLOBAL OPTIMIZATION 被引量:1
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作者 田蔚文 邬冬华 +1 位作者 张连生 李善良 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第2期202-209,共8页
The constrained global optimization problem being considered, a modified integral_level set method was illustrated based on Chew_Zheng's paper on Integral Global Optimization and (Wu's) paper on Implementable ... The constrained global optimization problem being considered, a modified integral_level set method was illustrated based on Chew_Zheng's paper on Integral Global Optimization and (Wu's) paper on Implementable Algorithm Convergence of Modified Integral_Level Set Method for Global Optimization Problem. It has two characters: 1) Each phase must construct a new function which has the same global optimal value as that of primitive objective function; 2) Comparing it with (Zheng's) method, solving level set procedure is avoided. An implementable algorithm also is given and it is proved that this algorithm is convergent. 展开更多
关键词 constrained global optimization integral-level set CONVERGENCE
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Integral Global Minimization of Constrained Problems with Discontinuous Penalty Functions 被引量:1
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作者 吴斌 崔洪泉 郑权 《Journal of Shanghai University(English Edition)》 CAS 2005年第5期385-390,共6页
A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained ... A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained and penalized minimization problem were investigated. A nonsequential algorithm was proposed. Numerical examples were given to illustrate the effectiveness of the algorithm. 展开更多
关键词 integral global minimization constrained minimization problems discontinuous penalty functions.
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A Level-Value Estimate Method for Solving Constrained Global Optimization
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作者 俞武扬 邬冬华 吕瑜佩 《Journal of Shanghai University(English Edition)》 CAS 2004年第2期128-131,共4页
The penalty method is a popular method for solving constrained optimization problems, which can change the constrained optimization to the unconstrained optimization. With the integral-level set method, a new approach... The penalty method is a popular method for solving constrained optimization problems, which can change the constrained optimization to the unconstrained optimization. With the integral-level set method, a new approach was proposed, which is briefer than the penalty method, to achieve the transform by constructing a simple function, then a level-value function was introduced to construct the equivalence between the unconstrained optimization and a nonlinear equality. By studying the properties of the function, a level-value estimate algorithm and an implementation algorithm were given by means of the uniform distribution of the good point set. Key words global optimization - constrained optimization - integral-level set - level-value estimate MSC 2000 90C05 展开更多
关键词 global optimization constrained optimization integral-level set level-value estimate
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A CLASS OF TRUST REGION METHODS FOR LINEAR INEQUALITY CONSTRAINED OPTIMIZATION AND ITS THEORY ANALYSIS:I.ALGORITHM AND GLOBAL CONVERGENCE
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作者 (Institute of Applied Mathematics, Academia Sinica, Beijing 100080).(Current address: Department of Mathematics, Hebei Teacher’s College, Shijiazhuang 050091). 《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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GLOBAL CONVERGENCE OF TRUST REGION ALGORITHM FOR EQUALITY AND BOUND CONSTRAINED NONLINEAR OPTIMIZATION
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作者 TongXiaojiao ZhouShuzi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期83-94,共12页
This paper presents a trust region two phase model algorithm for solving the equality and bound constrained nonlinear optimization problem. A concept of substationary point is given. Under suitable assumptions,the gl... This paper presents a trust region two phase model algorithm for solving the equality and bound constrained nonlinear optimization problem. A concept of substationary point is given. Under suitable assumptions,the global convergence of this algorithm is proved without assuming the linear independence of the gradient of active constraints. A numerical example is also presented. 展开更多
关键词 nonlinear optimization equality and bound constrained problem trust-region method global convergence.
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MERIT FUNCTION AND GLOBAL ALGORITHMFOR BOX CONSTRAINED VARIATIONALINEQUALITIES
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作者 张立平 高自友 赖炎连 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期63-71,共9页
The authors consider optimization methods for box constrained variational inequalities. First, the authors study the KKT-conditions problem based on the original problem. A merit function for the KKT-conditions proble... The authors consider optimization methods for box constrained variational inequalities. First, the authors study the KKT-conditions problem based on the original problem. A merit function for the KKT-conditions problem is proposed, and some desirable properties of the merit function are obtained. Through the merit function, the original problem is reformulated as minimization with simple constraints. Then, the authors show that any stationary point of the optimization problem is a solution of the original problem. Finally, a descent algorithm is presented for the optimization problem, and global convergence is shown. 展开更多
关键词 box constrained variational inequalities the KKT-conditions problem global convergence algorithm
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NEW SIMPLE SMOOTH MERIT FUNCTION FOR BOX CONSTRAINED VARIATIONAL INEQUALITIES AND DAMPED NEWTON TYPE METHOD 被引量:3
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作者 乌力吉 陈国庆 《应用数学和力学》 EI CSCD 北大核心 2005年第8期988-996,共9页
By introducing a smooth merit function for the median function, a new smooth merit function for box constrained variational inequalities (BVIs) was constructed. The function is simple and has some good differential pr... By introducing a smooth merit function for the median function, a new smooth merit function for box constrained variational inequalities (BVIs) was constructed. The function is simple and has some good differential properties. A damped Newton type method was presented based on it.Global and local superlinear/quadratic convergence results were obtained under mild conditions, and the finite termination property was also shown for the linear BVIs. Numerical results suggest that the method is efficient and promising. 展开更多
关键词 箱约束变分不等式 全局收敛 超线性收敛 有限步收敛
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基于Swin Transformer和图形推理的结直肠息肉分割方法
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作者 梁礼明 何安军 +1 位作者 阳渊 吴健 《工程科学学报》 EI CSCD 北大核心 2024年第5期897-907,共11页
针对结直肠息肉图像分割中病灶区域尺度变化大、边缘模糊以及息肉与正常组织对比度低等问题,导致病变区域分割精度低和分割边界存在伪影,提出一种基于Swin Transformer和图形推理的自适应网络.该网络一是利用Swin Transformer编码器逐... 针对结直肠息肉图像分割中病灶区域尺度变化大、边缘模糊以及息肉与正常组织对比度低等问题,导致病变区域分割精度低和分割边界存在伪影,提出一种基于Swin Transformer和图形推理的自适应网络.该网络一是利用Swin Transformer编码器逐层提取输入图像的全局上下文信息,弱化背景信息干扰,多尺度分析病变区域的显著性特点.二是提出全局与局部特征交互模块增强网络对复杂病灶的空间感知能力,突出待分割目标的关键位置信息,精准定位目标.三是通过区域引导图推理模块以图循环递推的方式挖掘先验信息之间的高阶显性关系,促进图间信息传递.四是设计面向边缘细节的边缘约束图推理模块,整合边缘细节,改善分割效果,提高分割精度.在CVC-ClinicDB、Kvasir、CVC-ColonDB和ETIS数据集上进行实验,其Dice系数分别为0.939,0.926,0.810和0.788,平均交并比分别为0.889,0.879,0.731和0.710,分割性能优于现有方法.仿真实验结果表明,对于形态结构复杂、对比度低和边缘模糊的结直肠息肉图像均有较高的分割精度. 展开更多
关键词 结直肠息肉 Swin Transformer 全局与局部特征交互 区域引导图推理 边缘约束图推理
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NEW SIMPLE SMOOTH MERIT FUNCTION FOR BOX CONSTRAINED VARIATIONAL INEQUALITIES AND DAMPED NEWTON TYPE METHOD 被引量:2
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作者 Ulji(乌力吉) CHEN Guo-qing(陈国庆) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第8期1083-1092,共10页
By introducing a smooth merit function for the median function, a new smooth merit function for box constrained variational inequalities (BVIs) was constructed. The function is simple and has some good differential ... By introducing a smooth merit function for the median function, a new smooth merit function for box constrained variational inequalities (BVIs) was constructed. The function is simple and has some good differential properties. A damped Newton type method was presented based on it. Global and local superlinear/ quadratic convergence results were obtained under mild conditions, and the finite termination property was also shown for the linear BVIs. Numerical results suggest that the method is efficient and promising. 展开更多
关键词 box constrained variational inequalities global convergence local superlinear or quadratic convergence finite termination property
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A SMOOTHING QP-FREE INFEASIBLE METHOD FOR NONLINEAR INEQUALITY CONSTRAINED OPTIMIZATION
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作者 Zhou Yan Pu Dingguo 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第4期425-433,共9页
In this paper, a smoothing QP-free infeasible method is proposed for nonlinear inequality constrained optimization problems. This iterative method is based on the solution of nonlinear equations which is obtained by t... In this paper, a smoothing QP-free infeasible method is proposed for nonlinear inequality constrained optimization problems. This iterative method is based on the solution of nonlinear equations which is obtained by the multipliers and the smoothing FisheroBurmeister function for the KKT first-order optimality conditions. Comparing with other QP-free methods, this method does not request the strict feasibility of iteration. In particular, this method is implementable and globally convergent without assuming the strict complementarity condition and the isolatedness of accumulation points. ~rthermore, the gradients of active constraints are not requested to be linearly independent. Preliminary numerical results indicate that this smoothing QP-free infeasible method is quite promising. 展开更多
关键词 inequality constrained optimization global convergence.
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A POTENTIAL REDUCTION ALGORITHM FOR LINEARLY CONSTRAINED CONVEX PROGRAMMING
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作者 Liang XimingCollege of Information Science & Engineering,Central South Univ.,Changsha 410083. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第4期439-445,共7页
A potential reduction algorithm is proposed for optimization of a convex function subject to linear constraints.At each step of the algorithm,a system of linear equations is solved to get a search direction and the Ar... A potential reduction algorithm is proposed for optimization of a convex function subject to linear constraints.At each step of the algorithm,a system of linear equations is solved to get a search direction and the Armijo's rule is used to determine a stepsize.It is proved that the algorithm is globally convergent.Computational results are reported. 展开更多
关键词 Potential reduction algorithm linearly constrained convex programming global convergence numerical experiments.
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Global solution for coupled nonlinear Klein-Gordon system
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作者 甘在会 张健 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第5期677-687,共11页
The global solution for a coupled nonlinear Klein-Gordon system in two- dimensional space was studied. First, a sharp threshold of blowup and global existence for the system was obtained by constructing a type of cros... The global solution for a coupled nonlinear Klein-Gordon system in two- dimensional space was studied. First, a sharp threshold of blowup and global existence for the system was obtained by constructing a type of cross-constrained variational problem and establishing so-called cross-invariant manifolds of the evolution flow. Then the result of how small the initial data for which the solution exists globally was proved by using the scaling argument. 展开更多
关键词 couple nonlinear Klein-Gordon system global solution BLOWUP cross- constrained variational problem sharp threshold
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Improved Conditions for the Existence and Uniqueness of Solutions to the General Equality Constrained Quadratic Programming Problem
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作者 Amadu Fullah Kamara Mohamed Abdulai Koroma Mujahid Abd Elmjed M.-Ali 《Open Journal of Optimization》 2012年第2期15-19,共5页
This paper presents an approach that directly utilizes the Hessian matrix to investigate the existence and uniqueness of global solutions for the ECQP problem. The novel features of this proposed algorithm are its uni... This paper presents an approach that directly utilizes the Hessian matrix to investigate the existence and uniqueness of global solutions for the ECQP problem. The novel features of this proposed algorithm are its uniqueness and faster rate of convergence to the solution. The merit of this algorithm is base on cost, accuracy and number of operations. 展开更多
关键词 HESSIAN Matrix global SOLUTIONS EQUALITY constrained Quadratic Programming Existence and Uniqueness of SOLUTIONS Lagrangian METHODS SCHUR COMPLEMENT METHODS
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A Modified Limited SQP Method For Constrained Optimization
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作者 Gonglin Yuan Sha Lu Zhengxin Wei 《Applied Mathematics》 2010年第1期8-17,共10页
In this paper, a modified variation of the Limited SQP method is presented for constrained optimization. This method possesses not only the information of gradient but also the information of function value. Moreover,... In this paper, a modified variation of the Limited SQP method is presented for constrained optimization. This method possesses not only the information of gradient but also the information of function value. Moreover, the proposed method requires no more function or derivative evaluations and hardly more storage or arithmetic operations. Under suitable conditions, the global convergence is established. 展开更多
关键词 constrainED Optimization LIMITED METHOD SQP METHOD global CONVERGENCE
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Generalized geometry theory on constrained rotating relativistic Birkhoffian systems
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作者 郑世旺 傅景礼 +2 位作者 施沈阳 陈立群 陈向伟 《Journal of Shanghai University(English Edition)》 CAS 2007年第2期115-120,共6页
This paper focuses on studying the generalized geometry theory of constrained rotating relativistic Birkhoffian systems. Based on the fact that relativistic rotating inertia is embedded in the Birkhoffian systems, the... This paper focuses on studying the generalized geometry theory of constrained rotating relativistic Birkhoffian systems. Based on the fact that relativistic rotating inertia is embedded in the Birkhoffian systems, the Pfaff action of rotating relativistic Birkhoffian systems was defined. The Pfaff-Birkhoff principles and Birkhoff's equations of the constrained rotating relativistic systems were obtained. The geometrical description, the exact properties and their forms on R T^*M for the constrained rotating relativistic Birkhoffian systems are given. The global analyses of the autonomous, semi-autonomous and non-autonomous constrained relativistic Birkhoff's equations as well as the geometrical properties of energy change for the constrained rotating relativistic Birkhoffian systems were also conducted. 展开更多
关键词 RELATIVITY constrained rotating Birkhoff's equation geometrical description global analysis
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GLOBAL CONVERGENCE OF NONMONOTONIC TRUST REGION ALGORITHM FOR NONLINEAR OPTIMIZATION 被引量:1
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作者 Tong Xiaojiao 1,2 \ Zhou Shuzi 1 1 Dept. of Appl.Math.,Hunan Univ.,Changsha 41 0 0 82 .2 Dept.of Math.,Changsha Univ.of Electric Power,Changsha41 0 0 77 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第2期201-210,共10页
A trust region algorithm for equality constrained optimization is given in this paper.The algorithm does not enforce strict monotonicity of the merit function for every iteration.Global convergence of the algorithm i... A trust region algorithm for equality constrained optimization is given in this paper.The algorithm does not enforce strict monotonicity of the merit function for every iteration.Global convergence of the algorithm is proved under the same conditions of usual trust region method. 展开更多
关键词 Nonmonotone algorithm equality constrains trust region method global convergence.
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Analytic Solutions to Optimal Control Problems with Constraints
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作者 Dan Wu 《Applied Mathematics》 2015年第14期2326-2339,共14页
In this paper, the analytic solutions to constrained optimal control problems are considered. A novel approach based on canonical duality theory is developed to derive the analytic solution of this problem by reformul... In this paper, the analytic solutions to constrained optimal control problems are considered. A novel approach based on canonical duality theory is developed to derive the analytic solution of this problem by reformulating a constrained optimal control problem into a global optimization problem. A differential flow is presented to deduce some optimality conditions for solving global optimizations, which can be considered as an extension and a supplement of the previous results in canonical duality theory. Some examples are given to illustrate the applicability of our results. 展开更多
关键词 constrainED Optimal Control ANALYTIC Solution CANONICAL DUALITY Theory global Optimization
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New smooth gap function for box constrained variational inequalities
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作者 张丽丽 李兴斯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第1期15-26,共12页
A new smooth gap function for the box constrained variational inequality problem (VIP) is proposed based on an integral global optimality condition. The smooth gap function is simple and has some good differentiable... A new smooth gap function for the box constrained variational inequality problem (VIP) is proposed based on an integral global optimality condition. The smooth gap function is simple and has some good differentiable properties. The box constrained VIP can be reformulated as a differentiable optimization problem by the proposed smooth gap function. The conditions, under which any stationary point of the optimization problem is the solution to the box constrained VIP, are discussed. A simple frictional contact problem is analyzed to show the applications of the smooth gap function. Finally, the numerical experiments confirm the good theoretical properties of the method. 展开更多
关键词 box constrained variational inequality problem (VIP) smooth gap function integral global optimality condition
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约束优化问题的单参数填充函数算法
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作者 马素霞 高岳林 +1 位作者 杨丽丽 柳迎春 《应用数学》 北大核心 2023年第4期891-902,共12页
本文研究约束优化问题的全局优化确定性方法.基于填充函数的定义,具体构造出了一个新的单参数填充函数并做了相关理论证明.结合SQP和BFGS局部极小化算法设计了新的填充函数全局优化算法.数值实验表明,该算法可行有效,具有良好的全局寻... 本文研究约束优化问题的全局优化确定性方法.基于填充函数的定义,具体构造出了一个新的单参数填充函数并做了相关理论证明.结合SQP和BFGS局部极小化算法设计了新的填充函数全局优化算法.数值实验表明,该算法可行有效,具有良好的全局寻优能力. 展开更多
关键词 全局优化 约束优化问题 填充函数方法
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