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High-Order Hamilton's Principle and the Hamilton's Principle of High-Order Lagrangian Function 被引量:2
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作者 ZHAO Hong-Xia MA Shan-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期297-302,共6页
In this paper, based on the theorem of the high-order velocity energy, integration and variation principle, the high-order Hamilton's principle of general holonomic systems is given. Then, three-order Lagrangian equa... In this paper, based on the theorem of the high-order velocity energy, integration and variation principle, the high-order Hamilton's principle of general holonomic systems is given. Then, three-order Lagrangian equations and four-order Lagrangian equations are obtained from the high-order Hamilton's principle. Finally, the Hamilton's principle of high-order Lagrangian function is given. 展开更多
关键词 Hamilton's principle high-order velocity energy integration and variation principle lagrangian function
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A multifractal model for linking Lagrangian and Eulerian velocity structure functions 被引量:1
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作者 Yu-Feng Dong Guo-Dong Jin 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第4期480-484,共5页
A multifractal model is developed to connect the Lagrangian multifractal dimensions with their Eulerian counterparts. We propose that the characteristic time scale of a Lagrangian quantity should be the Lagrangian tim... A multifractal model is developed to connect the Lagrangian multifractal dimensions with their Eulerian counterparts. We propose that the characteristic time scale of a Lagrangian quantity should be the Lagrangian time scale, and it should not be the Eulerian time scale which was widely used in previous studies on Lagrangian statistics. Using the present model, we can obtain the scaling exponents of Lagrangian velocity structure functions from the existing data or models of scaling exponents of Eulerian velocity structure functions. This model is validated by comparing its prediction with the results of experiments, direct numerical simulations, and the previous theoretical models. The comparison shows that the proposed model can better predict the scaling exponents of Lagrangian velocity structure functions, especially for orders larger than 6. 展开更多
关键词 lagrangian multifractal - Eulerian multifractal -Intermittency . Velocity structure functions
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EXACT AUGMENTED LAGRANGIAN FUNCTION FOR NONLINEAR PROGRAMMING PROBLEMS WITH INEQUALITY CONSTRAINTS
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作者 杜学武 张连生 +1 位作者 尚有林 李铭明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第12期1649-1656,共8页
An exact augmented Lagrangian function for the nonlinear nonconvex programming problems with inequality constraints was discussed. Under suitable hypotheses, the relationship was established between the local unconstr... An exact augmented Lagrangian function for the nonlinear nonconvex programming problems with inequality constraints was discussed. Under suitable hypotheses, the relationship was established between the local unconstrained minimizers of the augmented Lagrangian function on the space of problem variables and the local minimizers of the original constrained problem. Furthermore, under some assumptions, the relationship was also established between the global solutions of the augmented Lagrangian function on some compact subset of the space of problem variables and the global solutions of the constrained problem. Therefore, f^om the theoretical point of view, a solution of the inequality constrained problem and the corresponding values of the Lagrange multipliers can be found by the well-known method of multipliers which resort to the unconstrained minimization of the augmented Lagrangian function presented. 展开更多
关键词 local minimizer global minimizer nonlinear programming exact penalty function augmented lagrangian function
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A New Augmented Lagrangian Objective Penalty Function for Constrained Optimization Problems
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作者 Ying Zheng Zhiqing Meng 《Open Journal of Optimization》 2017年第2期39-46,共8页
In this paper, a new augmented Lagrangian penalty function for constrained optimization problems is studied. The dual properties of the augmented Lagrangian objective penalty function for constrained optimization prob... In this paper, a new augmented Lagrangian penalty function for constrained optimization problems is studied. The dual properties of the augmented Lagrangian objective penalty function for constrained optimization problems are proved. Under some conditions, the saddle point of the augmented Lagrangian objective penalty function satisfies the first-order Karush-Kuhn-Tucker (KKT) condition. Especially, when the KKT condition holds for convex programming its saddle point exists. Based on the augmented Lagrangian objective penalty function, an algorithm is developed for finding a global solution to an inequality constrained optimization problem and its global convergence is also proved under some conditions. 展开更多
关键词 CONSTRAINED Optimization Problems AUGMENTED lagrangian Objective PENALTY function SADDLE POINT Algorithm
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HYPERBOLIC LAGRANGIAN FUNCTIONS
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作者 于学刚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第12期0-0,0-0+0-0+0,共7页
关键词 TIME HYPERBOLIC lagrangian functionS
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有约束极大极小优化问题的修正Lagrangian算法 被引量:1
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作者 邓艳芳 童恒庆 贺素香 《武汉大学学报(理学版)》 CAS CSCD 北大核心 2008年第1期15-18,共4页
对于有不等式约束的极大极小优化问题,本文构造了一个修正的Lagrangian函数并分析了其在一般条件下的性质,建立了与之对应的修正Lagrangian算法.最后对文献中的几个问题给出了数值计算结果验证了算法.
关键词 修正lagrangian函数 修正lagrangian算法 约束极大极小优化问题
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双曲型Lagrangian函数 被引量:12
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作者 于学刚 《应用数学和力学》 EI CSCD 北大核心 1998年第12期1095-1100,共6页
双曲复数与Minkowski几何相对应,由四维时空间隔不变量和双曲型Lorentz变换可导出双曲型Lagrangian方程和Hamilton_Jacobi方程·
关键词 双曲四元数 广义惯性力 拉格朗日函数 双曲型
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应用Lagrangian乘子与对称罚函数结合算法分析实心轮胎动接触问题 被引量:1
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作者 于立彪 郑慕侨 《兵工学报》 EI CAS CSCD 北大核心 2002年第4期442-445,共4页
实心轮胎动接触问题是轮胎力学领域里的新课题 ,本文提出了Lagrangian乘子与对称罚函数法的结合算法 ,并以某履带车辆实心轮胎为例 ,应用该方法对其进行了动接触的有限元力学分析 ,获得了实心轮胎稳态滚动的应力场及接触变形情况。有限... 实心轮胎动接触问题是轮胎力学领域里的新课题 ,本文提出了Lagrangian乘子与对称罚函数法的结合算法 ,并以某履带车辆实心轮胎为例 ,应用该方法对其进行了动接触的有限元力学分析 ,获得了实心轮胎稳态滚动的应力场及接触变形情况。有限元计算结果表明该算法可以有效分析实心轮胎的动接触问题 ,而且对其结构优化。 展开更多
关键词 lagrangian乘子 对称罚函数 轮胎力学 实心轮胎 动接触 非线性有限元
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一类新的精确增广Lagrangian函数的性质
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作者 李梅霞 刘茜 《山东大学学报(理学版)》 CAS CSCD 北大核心 2013年第12期90-95,共6页
针对含有等式和不等式混合约束的最优化问题引进了一种新的精确增广Lagrangian函数。证明了该类增广Lagrangian函数的基本性质。进一步,在较弱的条件下证明了无约束问题的稳定点与原约束问题的KKT点之间的等价性。
关键词 约束最优化 增广lagrangian函数 性质
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基于不等式约束的一类新的增广Lagrangian函数
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作者 刘牧华 尚有林 李璞 《运筹学学报》 CSCD 2011年第4期115-123,共9页
针对含不等式约束的非线性规划问题,提出了一类新的增广Lagrangian函数,证明了其稳定点、整体极小点与原约束问题KKT点、整体极小点有对应关系,增广Lagrangian函数的局部极小点为原问题的局部极小点.基于给出的新的增广Lagrangian函数... 针对含不等式约束的非线性规划问题,提出了一类新的增广Lagrangian函数,证明了其稳定点、整体极小点与原约束问题KKT点、整体极小点有对应关系,增广Lagrangian函数的局部极小点为原问题的局部极小点.基于给出的新的增广Lagrangian函数进行了数值计算,验证了其可行性和有效性. 展开更多
关键词 局部极小点 整体极小点 增广lagrangian函数 KKT点
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半无限规划的一个非线性 Lagrangian对偶模型(英文)
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作者 杨洪礼 《经济数学》 2005年第1期94-99,共6页
本文给出半无限规划的一个对偶罚函数模型,该模型能处理目标函数不是凸函数的情形,从而凸(SIP)对偶为该模型的一个特例.并且,作为罚函数,本模型的罚因子比l1-罚函数要小,这使得算法更可行,最后,给出零对偶间隙证明.
关键词 半无限规划 拉格朗日对偶 罚函数 零对偶间隙
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常州城区大气氨时空变化特征分析
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作者 庄旻 余益军 +1 位作者 杨卫芬 王振 《环境监控与预警》 2026年第1期89-95,共7页
大气氨(NH_(3))作为大气中关键的活性碱性气体,可通过与二氧化硫(SO_(2))、氮氧化物(NO_(X))等酸性前体物反应生成二次无机气溶胶(SNA),是引起雾霾的重要原因之一。基于常州市2018—2022年高分辨率NH_(3)连续观测数据,结合气象资料与潜... 大气氨(NH_(3))作为大气中关键的活性碱性气体,可通过与二氧化硫(SO_(2))、氮氧化物(NO_(X))等酸性前体物反应生成二次无机气溶胶(SNA),是引起雾霾的重要原因之一。基于常州市2018—2022年高分辨率NH_(3)连续观测数据,结合气象资料与潜在源贡献因子分析(PSCF)模型,系统解析了NH_(3)的时空变化特征。结果表明:研究期间NH_(3)年均质量浓度为9.7μg/m^(3),呈现夏季(13.0μg/m^(3))>春季(9.9μg/m^(3))>秋季(9.3μg/m^(3))>冬季(6.8μg/m^(3))的季节变化特征;日变化呈单峰型,峰值出现在11:00(11.1μg/m^(3)),谷值出现在20:00(8.7μg/m^(3))。PSCF模型分析表明,常州城区春、秋、冬季主要受西南及东南方向气团输送影响,夏季则以本地排放为主。本研究揭示了常州市NH_(3)的时空变化和潜在来源,可为精细化管控颗粒物污染、持续改善空气质量及制定氨减排策略提供科学依据。 展开更多
关键词 大气氨 时空变化 拉格朗日轨迹模型 潜在源贡献因子分析模型 常州
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一类Lagrangian对偶问题的零对偶间隙性质及其最优路径的收敛性(英文) 被引量:1
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作者 刘丙状 王长钰 《运筹学学报》 CSCD 北大核心 2007年第1期73-84,共12页
针对一般的非线性规划问题,利用某些Lagrange型函数给出了一类Lagrangian对偶问题的一般模型,并证明它与原问题之间存在零对偶间隙.针对具体的一类增广La- grangian对偶问题以及几类由非线性卷积函数构成的Lagrangian对偶问题,详细讨... 针对一般的非线性规划问题,利用某些Lagrange型函数给出了一类Lagrangian对偶问题的一般模型,并证明它与原问题之间存在零对偶间隙.针对具体的一类增广La- grangian对偶问题以及几类由非线性卷积函数构成的Lagrangian对偶问题,详细讨论了零对偶间隙的存在性.进一步,讨论了在最优路径存在的前提下,最优路径的收敛性质. 展开更多
关键词 运筹学 对偶间隙 lagrangian函数 收敛性 最优路径
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一般约束非线性优化的增广Lagrangian算法 被引量:2
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作者 何小飞 彭叶辉 《湘南学院学报》 2004年第5期31-34,43,共5页
构造了一个求解一般约束非线性优化问题的增广Lagrangian算法 ,通过引进函数 φ(x) =max{g(x) ,- λr}可直接处理不等式的约束情形 .并且每次只需近似地求出对应增广Lagrangian罚函数的局部最小点 .在一般假设下 ,算法产生的点列的任意... 构造了一个求解一般约束非线性优化问题的增广Lagrangian算法 ,通过引进函数 φ(x) =max{g(x) ,- λr}可直接处理不等式的约束情形 .并且每次只需近似地求出对应增广Lagrangian罚函数的局部最小点 .在一般假设下 ,算法产生的点列的任意聚点都是问题的K 展开更多
关键词 算法 线性优化 优化问题 非线性 不等式 函数 求解 近似
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Higher-Order Lagrangian Equations of Higher-Order Motive Mechanical System 被引量:1
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作者 ZHAO Hong-Xia MA Shan-Jun SHI Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期479-481,共3页
In this paper, if the condition of variation δt = 0 is satisfied, the higher-order Lagrangian equations and higher-order Hamilton's equations, which show the consistency with the results of traditional analytical me... In this paper, if the condition of variation δt = 0 is satisfied, the higher-order Lagrangian equations and higher-order Hamilton's equations, which show the consistency with the results of traditional analytical mechanics, are obtained from the higher-order Lagrangian equations and higher-order Hamilton's equations. The results can enrich the theory of analytical mechanics. 展开更多
关键词 higher-order Lagrange function Hamilton function higher-order lagrangian equation
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Augmented Lagrangian Alternating Direction Method for Tensor RPCA 被引量:1
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作者 Ruru HAO Zhixun SU 《Journal of Mathematical Research with Applications》 CSCD 2017年第3期367-378,共12页
Tensor robust principal component analysis(TRPCA) problem aims to separate a low-rank tensor and a sparse tensor from their sum. This problem has recently attracted considerable research attention due to its wide ra... Tensor robust principal component analysis(TRPCA) problem aims to separate a low-rank tensor and a sparse tensor from their sum. This problem has recently attracted considerable research attention due to its wide range of potential applications in computer vision and pattern recognition. In this paper, we propose a new model to deal with the TRPCA problem by an alternation minimization algorithm along with two adaptive rankadjusting strategies. For the underlying low-rank tensor, we simultaneously perform low-rank matrix factorizations to its all-mode matricizations; while for the underlying sparse tensor,a soft-threshold shrinkage scheme is applied. Our method can be used to deal with the separation between either an exact or an approximate low-rank tensor and a sparse one. We established the subsequence convergence of our algorithm in the sense that any limit point of the iterates satisfies the KKT conditions. When the iteration stops, the output will be modified by applying a high-order SVD approach to achieve an exactly low-rank final result as the accurate rank has been calculated. The numerical experiments demonstrate that our method could achieve better results than the compared methods. 展开更多
关键词 tensor RPCA alternating direction method augmented lagrangian function high-order SVD
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A LAGRANGIAN LATTICE BOLTZMANN METHOD FOR EULER EQUATIONS
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作者 闫广武 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1998年第2期186-192,共7页
A Lagrangian lattice Boltzmann method for solving Euler equations is proposed. The key step in formulating this method is the introduction of the displacement distribution function. The equilibrium distribution functi... A Lagrangian lattice Boltzmann method for solving Euler equations is proposed. The key step in formulating this method is the introduction of the displacement distribution function. The equilibrium distribution function consists of macroscopic Lagrangian variables at time steps n and n + 1. It is different from the standard lattice Boltzmann method. In this method the element, instead of each particle, is required to satisfy the basic law. The element is considered as one large particle, which results in simpler version than the corresponding Eulerian one, because the advection term disappears here. Our numerical examples successfully reproduce the classical results. 展开更多
关键词 lagrangian lattice Boltzmann method displacement distribution functions lagrangian coordinates Euler equations
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Effects of QCD Vacuum and the Instanton Induced-Contributions to the Nucleon Structure Functions
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作者 A. Mirjalili M. Dehghani M.M. Yazdanpanah 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第2期179-186,共8页
The instanton induced cross section in deep inelastic kinematics is a subject which people are tendentious to investigate it. Instanton induced contributions are well defined for the nucleon structure function. The no... The instanton induced cross section in deep inelastic kinematics is a subject which people are tendentious to investigate it. Instanton induced contributions are well defined for the nucleon structure function. The non-perturbative contribution to the quark distributions of structure function, F2(x, Q2), is considered within an instanton model for the QCD vacuum. We find that the structure function may possess numerically large non-perterbative contributions which are related to the violation of chirality and correspond to the correction of parton distribution of the leading twist. It is shown that the instantons give a negative contribution to the structure function at the NLO approximation. A comparison between our results, considering instantaon effect, and the case when we do not take this effect is done. Taking into account the instanton size, p, via the modified running coupling constant we get to a good agreement between our results at the NLO and NNLO approximations and the available experimental data, specially at the low values of the Bjorken variable x 〈 0.1 which confirms the validity of our calculations. 展开更多
关键词 effective lagrangian instanton effects quark chirality flipping nucleon structure function
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Path Integral Quantization of Non-Natural Lagrangian
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作者 Ola A. Jarab’ah 《Journal of Applied Mathematics and Physics》 2023年第10期2932-2937,共6页
Path integral technique is discussed using Hamilton Jacobi method. The Hamilton Jacobi function of non-natural Lagrangian is obtained using separation of variables method. This function makes an important role in path... Path integral technique is discussed using Hamilton Jacobi method. The Hamilton Jacobi function of non-natural Lagrangian is obtained using separation of variables method. This function makes an important role in path integral quantization. The path integral is obtained as integration over the canonical phase space coordinates, which contains the generalized coordinate q and the generalized momentum p. One illustrative example is considered to explain the application of our formalism. 展开更多
关键词 Path Integral Quantization Hamilton Jacobi Equation Non-Natural lagrangian Hamilton Jacobi function
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The Polynomial Function Model in Born-Infeld Theory
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作者 DAI Bing-bing ZHANG Rui-feng 《Chinese Quarterly Journal of Mathematics》 2022年第3期221-236,共16页
Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation,we investigate the polynomial function model in Born-Infeld theory in this... Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation,we investigate the polynomial function model in Born-Infeld theory in this paper with the form of-([10α(φ′)^(2)]φ′)′=λf(φ(x)),whereλ>0 is a real parameter,f∈C 2(0,+∞)is a nonlinear function.We are interested in the exact number of positive solutions of the above nonlinear equation.We specifically develop for the problem combined with a careful analysis of a time-map method. 展开更多
关键词 Time-map analysis Exact number of solutions lagrangian action density The polynomial function model Born-Infeld theory
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