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THE EXACT ORDER OF |x-x_k|~s|I_k(x)|~t
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作者 史应光 《Analysis in Theory and Applications》 1992年第3期1-10,共10页
In this paper we give the exact order of丨x-x_k丨~丨l_k(x)丨~for any fixed nonnegative integers s and t,which is n^(-s),n^(-s)lnn and n^(1-)for s≤t-2,s=t-1 and s≥t, respectively.
关键词 x-x_k THE exact order OF s|I_k
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EXACT BOUNDARY CONTROLLABILITY FOR HIGHER ORDER QUASILINEAR HYPERBOLIC EQUATIONS 被引量:2
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作者 YuLixin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第2期127-141,共15页
By means of the existence and uniqueness of semi-global C1 solution to the mixed initial-boundary value problem with general nonlinear boundary conditions for first order quasilinear hyperbolic systems with zero eigen... By means of the existence and uniqueness of semi-global C1 solution to the mixed initial-boundary value problem with general nonlinear boundary conditions for first order quasilinear hyperbolic systems with zero eigenvalues,the local exact boundary controllability for higher order quasilinear hyperbolic equations is established. 展开更多
关键词 semi-global C^1 solution exact boundary controllability higher order quasilinear hyperbolic system.
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Exact solutions for unsteady unidirectional flows of a generalized second-order fluid through a rectangular conduit 被引量:1
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作者 J. Kang M. Xu School of Mathematics, Institute of Applied Mathematics,Shandong University, 250100 Jinan, China M. Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第2期181-186,共6页
The exact solutions are obtained for unsteady unidirectional flows of a generalized second-order fluid through a rectangular conduit. The fractional calculus in the constitutive relationship of a non-Newtonian fluid i... The exact solutions are obtained for unsteady unidirectional flows of a generalized second-order fluid through a rectangular conduit. The fractional calculus in the constitutive relationship of a non-Newtonian fluid is introduced. We construct the solutions by means of Fourier transform and the discrete Laplace transform of the sequential derivatives and the double finite Fourier transform. The solutions for Newtonian fluid between two infinite parallel plates appear as limiting cases of our solutions. 展开更多
关键词 Generalized second-order fluid - Rectangularconduit Fractional calculus exact solutions
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Exact Solution to Nonlinear Differential Equations of Fractional Order via (<i>G’</i>/<i>G</i>)-Expansion Method 被引量:4
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作者 Muhammad Younis Asim Zafar 《Applied Mathematics》 2014年第1期1-6,共6页
In this article, a new application to find the exact solutions of nonlinear partial time-space fractional differential Equation has been discussed. Firstly, the fractional complex transformation has been implemented t... In this article, a new application to find the exact solutions of nonlinear partial time-space fractional differential Equation has been discussed. Firstly, the fractional complex transformation has been implemented to convert nonlinear partial fractional differential Equations into nonlinear ordinary differential Equations. Afterwards, the (G'/G)-expansion method has been implemented, to celebrate the exact solutions of these Equations, in the sense of modified Riemann-Liouville derivative. As application, the exact solutions of time-space fractional Burgers’ Equation have been discussed. 展开更多
关键词 exact Solution to Nonlinear Differential Equations of Fractional order VIA (G’/G)-Expansion Method
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Darboux Transformation and Exact Solutions for High Order Nonlocal Coupled AKNS System
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作者 Xiangpeng Xin Zengxin Guo +1 位作者 Yanxin Hu Linlin Zhang 《Journal of Applied Mathematics and Physics》 2021年第11期2592-2608,共17页
In this paper, we investigate an integrable high order nonlocal coupled Ablowitz-Kaup-Newell-Segur (AKNS) system for the first time. With the aid of Lax pair of this nonlocal system, Darboux transformation (DT) and ne... In this paper, we investigate an integrable high order nonlocal coupled Ablowitz-Kaup-Newell-Segur (AKNS) system for the first time. With the aid of Lax pair of this nonlocal system, Darboux transformation (DT) and new soliton-like solutions are obtained. Different from local equations, Darboux transformation of nonlocal systems needs to meet certain conditions. In this article, under the condition of symmetry reduction, the components of Darboux transformation need to satisfy <img src="Edit_6aa5df34-2f85-4c91-a185-17195a7f82ee.bmp" alt="" />. In order to study the dynamic information of the solutions, the images of the solutions are given. 展开更多
关键词 High order Nonlocal Equation Darboux Transformation exact Solution
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Explicit Iterative Methods of Second Order and Approximate Inverse Preconditioners for Solving Complex Computational Problems
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作者 Anastasia-Dimitra Lipitakis 《Applied Mathematics》 2020年第4期307-327,共21页
Explicit Exact and Approximate Inverse Preconditioners for solving complex linear systems are introduced. A class of general iterative methods of second order is presented and the selection of iterative parameters is ... Explicit Exact and Approximate Inverse Preconditioners for solving complex linear systems are introduced. A class of general iterative methods of second order is presented and the selection of iterative parameters is discussed. The second order iterative methods behave quite similar to first order methods and the development of efficient preconditioners for solving the original linear system is a decisive factor for making the second order iterative methods superior to the first order iterative methods. Adaptive preconditioned Conjugate Gradient methods using explicit approximate preconditioners for solving efficiently large sparse systems of algebraic equations are also presented. The generalized Approximate Inverse Matrix techniques can be efficiently used in conjunction with explicit iterative schemes leading to effective composite semi-direct solution methods for solving large linear systems of algebraic equations. 展开更多
关键词 APPROXIMATE INVERSE PRECONDITIONERS ITERATIVE METHODS Second order ITERATIVE Schemes exact INVERSE METHODS APPROXIMATE INVERSE EXPLICIT Preconditioning Conjugate Gradients Convergence Analysis
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Illustrative Application of the 2<sup>nd</sup>-Order Adjoint Sensitivity Analysis Methodology to a Paradigm Linear Evolution/Transmission Model: Point-Detector Response 被引量:2
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第3期355-381,共27页
This work illustrates the application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a mathematical model that can simulate the evolution and/or tr... This work illustrates the application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a mathematical model that can simulate the evolution and/or transmission of particles in a heterogeneous medium. The model response is the value of the model’s state function (particle concentration or particle flux) at a point in phase-space, which would simulate a pointwise measurement of the respective state function. This paradigm model admits exact closed-form expressions for all of the 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities to the model’s uncertain parameters and domain boundaries. These closed-form expressions can be used to verify the numerical results of production and/or commercial software, e.g., particle transport codes. Furthermore, this paradigm model comprises many uncertain parameters which have relative sensitivities of identical magnitudes. Therefore, this paradigm model could serve as a stringent benchmark for inter-comparing the performances of all deterministic and statistical sensitivity analysis methods, including the 2<sup>nd</sup>-CASAM. 展开更多
关键词 Second-order Adjoint Comprehensive Sensitivity Analysis Methodology (2nd-CASAM) Evolution Benchmark Model exact and Efficient Computation of First- and Second-order Response Sensitivities
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Illustrative Application of the 2<sup>nd</sup>-Order Adjoint Sensitivity Analysis Methodology to a Paradigm Linear Evolution/Transmission Model: Reaction-Rate Detector Response 被引量:2
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第3期382-397,共16页
This work continues the illustrative application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a benchmark mathematical model that can simulate th... This work continues the illustrative application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a benchmark mathematical model that can simulate the evolution and/or transmission of particles in a heterogeneous medium. The model response considered in this work is a reaction-rate detector response, which provides the average interactions of particles with the respective detector or, alternatively, the time-average of the concentration of a mixture of substances in a medium. The definition of this model response includes both uncertain boundary points of the benchmark, thereby providing both direct and indirect contributions to the response sensitivities stemming from the boundaries. The exact expressions for the 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities to the boundary and model parameters obtained in this work can serve as stringent benchmarks for inter-comparing the performances of all (deterministic and statistical) sensitivity analysis methods. 展开更多
关键词 Second-order Adjoint Comprehensive Sensitivity Analysis Methodology (2nd-CASAM) Evolution Benchmark Model exact and Efficient Computation of First- and Second-order Response Sensitivities
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分数阶(2+1)维Hybrid-Lattice系统的精确解
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作者 袁满玉 李浓森 +1 位作者 张瑞岗 崔继峰 《内蒙古大学学报(自然科学版)》 CAS 2024年第6期396-402,共7页
将G′/G展开法应用到离散分数阶系统,成功求解了分数阶(2+1)维Hybrid-Lattice系统的精确解。研究结果显示,利用该方法求解分数阶(2+1)维Hybrid-Lattice系统十分简洁高效。
关键词 G′/G展开法 离散分数阶系统 精确解
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APPROXIMATION BY COMPLEX SZSZ-DURRMEYER OPERATORS IN COMPACT DISKS 被引量:3
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作者 Sorin G.GAL Vijay GUPTA 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1157-1165,共9页
In the present paper, we deal with the complex Szasz-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on comp... In the present paper, we deal with the complex Szasz-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on compact disks. Also, the exact order of approximation is found. 展开更多
关键词 complex Szasz-Durrmeyer operators Voronovksaja type result exact order of approximation in compact disks simultaneous approximation
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区间线性规划的标准型及其求解 被引量:39
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作者 郭均鹏 吴育华 《系统工程》 CSCD 北大核心 2003年第3期79-82,共4页
定义区间线性规划的标准型 ,给出一种反映决策者满意度的区间数序关系 ,基于此将区间不等式约束转化为确定型约束 ;讨论区间等式约束的含义并将其化为确定型不等式约束。在此基础上将区间线性规划转化为一个确定型线性规划并进行求解。... 定义区间线性规划的标准型 ,给出一种反映决策者满意度的区间数序关系 ,基于此将区间不等式约束转化为确定型约束 ;讨论区间等式约束的含义并将其化为确定型不等式约束。在此基础上将区间线性规划转化为一个确定型线性规划并进行求解。最后给出一个算例。 展开更多
关键词 区间线性规划 标准型 运筹学 序关系 目标函数
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基于决策者满意度的区间DEA的求解 被引量:7
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作者 李汶华 郭均鹏 《管理工程学报》 CSSCI 2005年第1期87-89,共3页
定义了一种反映决策者满意度的区间数序关系,基于此将区间DEA中的区间不等式约束转化为确定型约束。研究了区间DEA模型向确定型DEA模型转化过程中的数据一致性问题。在保持数据一致性的前提下,根据决策者给出的满意度水平,将区间DEA转... 定义了一种反映决策者满意度的区间数序关系,基于此将区间DEA中的区间不等式约束转化为确定型约束。研究了区间DEA模型向确定型DEA模型转化过程中的数据一致性问题。在保持数据一致性的前提下,根据决策者给出的满意度水平,将区间DEA转化为确定型DEA并进行求解。最后给出算例,并总结和分析了决策单元的DEA效率值随满意度水平变化的规律。 展开更多
关键词 区间DEA 确定型DEA 满意度 序关系 数据一致性
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一个新的低阶精确罚函数及其性质 被引量:4
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作者 陈纯荣 孟开文 李声杰 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第5期123-126,共4页
为了求解不等式约束非线性规划问题,提出一个新的低阶罚函数,它是经典l1罚函数和低阶罚函数的一种组合。理论分析和例子表明,新提出的低阶罚函数具有这两种罚函数的各自优点。另外,还提出了一个求解此问题的罚函数方法并证明了该方法的... 为了求解不等式约束非线性规划问题,提出一个新的低阶罚函数,它是经典l1罚函数和低阶罚函数的一种组合。理论分析和例子表明,新提出的低阶罚函数具有这两种罚函数的各自优点。另外,还提出了一个求解此问题的罚函数方法并证明了该方法的全局收敛性。 展开更多
关键词 不等式约束非线性规划 精确罚函数 低阶罚函数
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约束优化问题的一类光滑罚算法的全局收敛特性(英文) 被引量:2
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作者 王长钰 赵文玲 《运筹学学报》 CSCD 北大核心 2015年第3期151-160,共10页
对约束优化问题给出了一类光滑罚算法.它是基于一类光滑逼近精确罚函数l_p(p∈(0,1])的光滑函数L_p而提出的.在非常弱的条件下,建立了算法的一个摄动定理,导出了算法的全局收敛性.特别地,在广义Mangasarian-Fromovitz约束规范假设下,证... 对约束优化问题给出了一类光滑罚算法.它是基于一类光滑逼近精确罚函数l_p(p∈(0,1])的光滑函数L_p而提出的.在非常弱的条件下,建立了算法的一个摄动定理,导出了算法的全局收敛性.特别地,在广义Mangasarian-Fromovitz约束规范假设下,证明了当p=1时,算法经过有限步迭代后,所有迭代点都是原问题的可行解;当p∈(0,1)时,算法经过有限迭代后,所有迭代点都是原问题可行解集的内点. 展开更多
关键词 精确罚函数 低阶精确罚函数 光滑逼近精确罚 光滑罚算法 广义Mangasarian-Fromovitz约束规范
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格序模f-张量积函子的正合性与平坦格序模 被引量:3
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作者 周伟 《四川师范大学学报(自然科学版)》 CAS CSCD 1992年第3期52-57,共6页
本文证明了如下结果:设M是有单位元可换格序环R上的格序模和l-模同态范畴,F是R上的f-模和l-模同态范畴,M∈M,则F=M(?)()是M 到F 的共变函子,进而是右正合函子.设R 是有单位元的可换全序环,视R 为自身上的格序模,则R 是平坦的.
关键词 f-张量积函子 格序模正合列 右正合函子 平坦格序模
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二阶变系数线性微分方程通解的进一步研究 被引量:6
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作者 文武 《四川文理学院学报》 2016年第5期7-12,共6页
针对求二阶变系数线性微分方程的解未给出详细的研究,而在实际中有时要用到一般的求解法的情况,经过变量替换和算子理论以及恰当方程的处理方法来达到降阶,通过降阶法转化为求一阶线性微分方程的通解,从而达到对二阶变系数线性微分方程... 针对求二阶变系数线性微分方程的解未给出详细的研究,而在实际中有时要用到一般的求解法的情况,经过变量替换和算子理论以及恰当方程的处理方法来达到降阶,通过降阶法转化为求一阶线性微分方程的通解,从而达到对二阶变系数线性微分方程通解的进一步研究的目的. 展开更多
关键词 二阶变系数线性微分方程 变量替换 恰当方程 降阶法 通解
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不等式约束优化问题的低阶精确罚函数的光滑化算法(英文) 被引量:3
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作者 连淑君 《运筹学学报》 CSCD 北大核心 2012年第2期51-64,共14页
对不等式约束优化问题提出了一个低阶精确罚函数的光滑化算法.首先给出了光滑罚问题、非光滑罚问题及原问题的目标函数值之间的误差估计,进而在弱的假设之下证明了光滑罚问题的全局最优解是原问题的近似全局最优解.最后给出了一个基于... 对不等式约束优化问题提出了一个低阶精确罚函数的光滑化算法.首先给出了光滑罚问题、非光滑罚问题及原问题的目标函数值之间的误差估计,进而在弱的假设之下证明了光滑罚问题的全局最优解是原问题的近似全局最优解.最后给出了一个基于光滑罚函数的求解原问题的算法,证明了算法的收敛性,并给出数值算例说明算法的可行性. 展开更多
关键词 约束非线性规划 精确罚函数 低阶罚函数 光滑精确罚函数 二阶充分条件
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药物控释系统中分数阶反常扩散可动边界问题的精确解 被引量:3
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作者 刘君义 徐明瑜 《山东大学学报(理学版)》 CAS CSCD 北大核心 2003年第1期28-32,共5页
将分形动力学机制引入药物控制释放系统 ,应用分数阶Green函数、及Wright函数对非线性问题给出了精确解 .证明了药物从片状高聚物药物控释系统中释放的知名Ritger Peppas半经验公式 .给出了药物释放量的近似表达式 .
关键词 药物控释系统 可动边界 分数阶反常扩散 分数阶Green函数 精确解
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非线性与立方非线性Schrdinger方程的多级包络周期解 被引量:1
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作者 肖亚峰 薛海丽 张鸿庆 《原子与分子物理学报》 CAS CSCD 北大核心 2011年第4期724-730,共7页
本文基于Jacobi椭圆函数和Lamé方程,应用摄动法研究了非线性与立方非线性Schrdinger方程,获得了其新的多级包络周期解.这些解在极限条件下可以退化为各种形式的包络孤波解.
关键词 Laine方程 多级准确解 JACOBI椭圆函数 摄动法 非线性演化方程
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一类高阶非线性波方程的李群分析、最优系统、精确解和守恒律 被引量:9
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作者 李凯辉 刘汉泽 辛祥鹏 《物理学报》 SCIE EI CAS CSCD 北大核心 2016年第14期1-7,共7页
本文运用李群分析的方法研究了一类高阶非线性波方程,得到了五阶非线性波方程的对称以及方程的最优系统,进而运用幂级数的方法,求得了方程的精确幂级数解.最后,给出了五阶非线性波方程的一些守恒律.
关键词 李群分析 高阶非线性波方程 精确解 守恒律
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