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A Set of Almost Automorphic Functions and Applications
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作者 William Dimbour Vincent Valmorin 《Applied Mathematics》 2024年第1期9-21,共13页
For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-al... For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem. 展开更多
关键词 Almost Automorphic functions s-Almost Automorphic functions Differential Equation with Piecewise Constant argument of Generalized Type
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Flow through a Variable Permeability Brinkman Porous Core
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作者 M. S. Abu Zaytoon T. L. Alderson M. H. Hamdan 《Journal of Applied Mathematics and Physics》 2016年第4期766-778,共13页
In this work, we consider the flow through composite porous layers of variable permeability, with the middle layer representing a porous core bounded by two Darcy layers. Brinkman’s equation is valid in the middle la... In this work, we consider the flow through composite porous layers of variable permeability, with the middle layer representing a porous core bounded by two Darcy layers. Brinkman’s equation is valid in the middle layer and has been reduced to an Airy’s inhomogeneous differential equation. Solution is obtained in terms of Airy’s functions and the Nield-Kuznetsov function. 展开更多
关键词 Airy’s functions variable Permeability Porous Layers
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Green's function for T-stress of semi-infinite plane crack
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作者 崔元庆 杨卫 仲政 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第8期973-980,共8页
Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single... Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single inclined concentrated force at an interior point. The complex potentials are obtained based on a superposition principle, which provide the solutions to the plane problems of elasticity. The regular parts of the potentials are extracted in an asymptotic analysis. Based on the regular parts, Green’s function for the T-stress is obtained in a straightforward manner. Furthermore, Green’s functions are derived for a pair of symmetrically and anti-symmetrically concentrated forces by the superimposing method. Then, Green’s function is used to predict the domain-switch-induced T-stress in a ferroelectric double cantilever beam (DCB) test. The T-stress induced by the electromechanical loading is used to judge the stable and unstable crack growth behaviors observed in the test. The prediction results generally agree with the experimental data. 展开更多
关键词 Green’s function T-sTREss complex variable function semi-infinite crack fracture mechanics
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基于T-S模型的体操机器人系统模糊变结构控制 被引量:10
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作者 郑艳 郑秀萍 +1 位作者 褚俊霞 井元伟 《控制与决策》 EI CSCD 北大核心 2006年第1期34-37,共4页
针对体操机器人(A crobot)这类非线性系统,给出一种基于T-S模型的模糊变结构控制律设计.首先采用T-S模型建模,得到A crobot的全局模糊模型;然后基于Lyapunov理论设计出保证A crobot全局渐近稳定的模糊变结构平衡控制器.仿真结果表明,所... 针对体操机器人(A crobot)这类非线性系统,给出一种基于T-S模型的模糊变结构控制律设计.首先采用T-S模型建模,得到A crobot的全局模糊模型;然后基于Lyapunov理论设计出保证A crobot全局渐近稳定的模糊变结构平衡控制器.仿真结果表明,所设计的模糊变结构控制器与普通变结构控制器相比,可使A crobot系统在垂直向上平衡点附近具有更大的吸引域和更强的鲁棒性. 展开更多
关键词 体操机器人 变结构控制 T—s模型 吸引域 李雅普诺夫函数
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二元函数S-粗集及其关系定理
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作者 吕昆 王磊 《山东科学》 CAS 2014年第1期102-105,共4页
给出了二元函数S-粗集的数学结构和特性,提出了二元函数S-粗集与一元函数S-粗集、S-粗集、二元函数粗集、Pawlak粗集的关系定理。
关键词 二元函数s-粗集 一元函数s-粗集 二元函数粗集 关系定理
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多元函数单向S-粗集 被引量:1
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作者 杜素勤 《甘肃联合大学学报(自然科学版)》 2007年第4期4-7,共4页
给出了二元函数单向S-粗集的数学结构和特性.提出了二元函数单向S-粗集与一元函数单向S-粗集、单向S-粗集的关系定理,二元函数单向S-粗集与二元函数粗集的关系定理.最后以实例说明二元函数单向S-粗集的存在.
关键词 二元函数单向s-粗集 二元函数单向s-粗集的结构 关系定理
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变精度变异函数S-粗集与F-结构
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作者 吴全荣 邱锦明 《武夷学院学报》 2008年第5期10-14,共5页
动态系统规律知识是规律对象(规律外延)与规律属性(规律内涵)的统一体,利用变异单向函数S-粗集与变精度粗集提出变精度变异单向函数S-粗集的概念和它的F-结构,给出变精度变异单向函数S-粗集的有关性质定理和推论,对此进行了讨论。应用... 动态系统规律知识是规律对象(规律外延)与规律属性(规律内涵)的统一体,利用变异单向函数S-粗集与变精度粗集提出变精度变异单向函数S-粗集的概念和它的F-结构,给出变精度变异单向函数S-粗集的有关性质定理和推论,对此进行了讨论。应用变精度变异函数单向S-粗集对动态系统的内涵规律的精度进行数据挖掘。容易挖掘-发现出动态系统中规律的相关性和规律的近似决策规则。变精度变异单向函数S-粗集为研究动态系统规律提供了一种新的途径。 展开更多
关键词 函数s-粗集 变精度粗集 变精度变异单向函数s-粗集 数据挖掘
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基于S函数的改进变步长LMS自适应算法 被引量:10
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作者 雷章勇 彭志炜 +1 位作者 张俨 赵雪娇 《电光与控制》 北大核心 2018年第10期52-56,共5页
变步长LMS自适应滤波算法通过构造步长因子来进行权值调整,使算法具有较快的收敛速度和较小的稳态误差。为了进一步改善算法的性能,提出一种基于S函数的改进变步长LMS自适应算法。该算法基于S函数的曲线特点,通过对函数的平移变换得到... 变步长LMS自适应滤波算法通过构造步长因子来进行权值调整,使算法具有较快的收敛速度和较小的稳态误差。为了进一步改善算法的性能,提出一种基于S函数的改进变步长LMS自适应算法。该算法基于S函数的曲线特点,通过对函数的平移变换得到算法步长因子的表达式。为满足算法的可控性和抗干扰能力的要求,通过引入可控参数和误差向量自相关值来调整步长因子,得到算法的最终模型。详细分析了模型中各参数的取值对步长因子和滤波性能的影响。与现有算法的仿真结果对比表明,该算法在收敛速度、稳态误差及抗干扰能力方面的性能均有了很大的改善。 展开更多
关键词 LMs自适应滤波 s函数 改进变步长 滤波性能
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基于T-S模型的Chua混沌系统模糊变结构控制
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作者 王铁权 井元伟 《微计算机信息》 2010年第10期22-23,28,共3页
针对Chua混沌系统这一复杂的非线性系统给出一种基于T-S模型的模糊变结构控制律设计。首先采用T-S模糊动态模型描述非线性系统,得到混沌系统的全局模糊模型;然后采用Lyapunov稳定性理论设计出确保模糊动态模型全局渐近稳定的变结构控制... 针对Chua混沌系统这一复杂的非线性系统给出一种基于T-S模型的模糊变结构控制律设计。首先采用T-S模糊动态模型描述非线性系统,得到混沌系统的全局模糊模型;然后采用Lyapunov稳定性理论设计出确保模糊动态模型全局渐近稳定的变结构控制器,将模糊控制与成熟的线性变结构控制相结合,来解决非线性系统控制问题。仿真验证了方案的有效性。模糊控制器简单,规则少。 展开更多
关键词 Chua混沌系统 非线性 变结构控制 T-s模型 李雅普诺夫函数
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S函数变步长LMS算法的一种L2范数修正 被引量:2
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作者 徐华鹏 高丽 《兰州交通大学学报》 CAS 2019年第2期51-57,共7页
为了提高S函数变步长LMS算法的综合性能和抗干扰能力,引入L2范数控制步长更新.在L2范数中引入输入信号,对输入信号实施动态地跟踪,以提高算法的抗干扰能力;利用归一化输入信号代替原始信号,便于处理信号且可以降低输入信号动态范围对算... 为了提高S函数变步长LMS算法的综合性能和抗干扰能力,引入L2范数控制步长更新.在L2范数中引入输入信号,对输入信号实施动态地跟踪,以提高算法的抗干扰能力;利用归一化输入信号代替原始信号,便于处理信号且可以降低输入信号动态范围对算法的影响.在高和低信噪比条件下的仿真结果表明:相较于其他的变步长LMS算法,所提出算法收敛速度更快和稳态误差更小. 展开更多
关键词 变步长 LMs算法 s函数 L2范数 归一化
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基于T-S模糊神经网络组合模型的CPI预测 被引量:4
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作者 荀新新 张德生 +1 位作者 王雁 杜方欣 《陕西科技大学学报(自然科学版)》 2014年第3期173-176,共4页
首先对我国CPI和PPI序列建立了VAR模型和加外生变量的半参数自回归模型,得到CPI的拟合值和预测值;然后在这两种单模型的基础上,结合模糊数学和神经网络知识,建立了T-S模糊神经网络组合预测模型;最后对三种模型进行比较.结果显示,T-S模... 首先对我国CPI和PPI序列建立了VAR模型和加外生变量的半参数自回归模型,得到CPI的拟合值和预测值;然后在这两种单模型的基础上,结合模糊数学和神经网络知识,建立了T-S模糊神经网络组合预测模型;最后对三种模型进行比较.结果显示,T-S模糊神经网络组合模型提高了预测结果的可靠性和准确性. 展开更多
关键词 VAR模型 加外生变量的半参数自回归模型 T-s模糊神经网络组合模型 隶属度函数
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EXISTENCE OF PERIODIC SOLUTIONS TO A p-LAPLACIAN NEUTRAL FUNCTIONAL DIFFERENTIAL EQUATION WITH VARIABLE PARAMETER 被引量:2
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作者 Feng Liang, Shiping Lu Dept. of Math., Anhui Normal University, Wuhu 241000, Anhui 《Annals of Differential Equations》 2010年第2期165-173,共9页
By the generalized Borsuk theorem in coincidence degree theory, a p-Laplacian neutral functional differential equation is studied. A new result on the existence of periodic solution is obtained. The interest is that s... By the generalized Borsuk theorem in coincidence degree theory, a p-Laplacian neutral functional differential equation is studied. A new result on the existence of periodic solution is obtained. The interest is that some coeffcient in it is not a constant function and its sign can be changeable, which is different from that in the known literatures. 展开更多
关键词 periodic solution neutral functional differential equation P-LAPLACIAN variable sign deviating argument generalized Borsuk theorem
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基于S-函数改进电导法的光伏阵列最大功率点的跟踪 被引量:2
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作者 蔺娜 刘星 葛晨 《西北水电》 2014年第2期90-92,99,共4页
光伏阵列最大功率点的控制策略是光伏递变器研究的重点之一,文章在深入研究传统电导增量法工作原理的基础上,提出一种基于S-函数的恒电压启动的变步长电导增量法来实现最大功率点跟踪,并在MATLAB/Simulink环境下搭建了光伏阵列的仿真模... 光伏阵列最大功率点的控制策略是光伏递变器研究的重点之一,文章在深入研究传统电导增量法工作原理的基础上,提出一种基于S-函数的恒电压启动的变步长电导增量法来实现最大功率点跟踪,并在MATLAB/Simulink环境下搭建了光伏阵列的仿真模型,通过对比仿真结果可以证明,改进的电导增量法能够准确地反映出光伏阵列输出电压和电流的非线性特性,并且能快速高效地跟踪最大功率点。 展开更多
关键词 光伏阵列 最大功率点 跟踪 s-函数 电导增量法 恒电压变步长
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基于S形函数的变步长LMS算法 被引量:2
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作者 亢润东 宋国强 《无线电工程》 2013年第11期29-32,共4页
针对定步长LMS算法在收敛速度、时变跟踪能力和稳态失调噪声几个重要指标上不能兼顾的问题,引入人工神经网络中一种常用激励函数———S形函数,并将其应用于变步长LMS算法中。结合算法对收敛速度、精度及稳态失调噪声的要求,引入改变S... 针对定步长LMS算法在收敛速度、时变跟踪能力和稳态失调噪声几个重要指标上不能兼顾的问题,引入人工神经网络中一种常用激励函数———S形函数,并将其应用于变步长LMS算法中。结合算法对收敛速度、精度及稳态失调噪声的要求,引入改变S形函数曲线曲率及收敛终值的2个参数:α和β。分析当α和β值固定时的情况,仿真结果表明定参数算法若其值选择不当会引起较大误差。按照步长值在时变阶段自适应增大,在稳态阶段步长很小的原则,构造了变参数α(n)和β(n),仿真结果表明变参数算法兼顾多个参数,整体表现较好。 展开更多
关键词 s形函数 变步长LMs 误差信号 稳态失调噪声
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基于新颖S型转换函数的二进制粒子群优化算法求解具有单连续变量的背包问题 被引量:10
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作者 王泽昆 贺毅朝 +1 位作者 李焕哲 张发展 《计算机应用》 CSCD 北大核心 2021年第2期461-469,共9页
为了高效求解具有单连续变量的背包问题(KPC),首先基于高斯误差函数提出了一个新颖S型转换函数,给出了利用该转换函数将一个实向量转换为0-1向量的新方法,由此提出了一个新的二进制粒子群优化(NBPSO)算法;然后,利用KPC的第二数学模型,... 为了高效求解具有单连续变量的背包问题(KPC),首先基于高斯误差函数提出了一个新颖S型转换函数,给出了利用该转换函数将一个实向量转换为0-1向量的新方法,由此提出了一个新的二进制粒子群优化(NBPSO)算法;然后,利用KPC的第二数学模型,并且把NBPSO与处理KPC不可行解的有效算法相结合,提出了求解KPC的一个新方法。为了检验NBPSO求解KPC的性能,利用NBPSO求解四类大规模KPC实例,并把所得计算结果与基于其他S、V型转换函数的二进制粒子群优化算法(BPSO)、具有混合编码的单种群二进制差分演化算法(S-HBDE)、具有混合编码的双种群二进制差分演化算法(B-HBDE)和二进制粒子群优化算法(BPSO)等的计算结果相比较。比较结果表明NBPSO不仅平均计算结果更优,而且稳定性更佳,说明NBPSO的性能比其他算法有显著提升。 展开更多
关键词 具有单连续变量的背包问题 组合优化问题 二进制粒子群优化算法 s型转换函数
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基于S函数的inc算法在光伏发电MPPT上的应用
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作者 张振 张发明 谭会生 《湖南工业大学学报》 2018年第1期76-80,共5页
传统的变步长inc算法虽然在控制性能上有优势,但是不仅计算量较大,影响跟踪速度;且稳定步长较大,系统稳定性有待提高。因此,基于Matlab/Simulink平台搭建了光伏发电最大功率点跟踪技术控制模型,利用Simulink中S函数编程,实现了新型变步... 传统的变步长inc算法虽然在控制性能上有优势,但是不仅计算量较大,影响跟踪速度;且稳定步长较大,系统稳定性有待提高。因此,基于Matlab/Simulink平台搭建了光伏发电最大功率点跟踪技术控制模型,利用Simulink中S函数编程,实现了新型变步长inc算法仿真,并得出了相关结论。仿真实验结果表明,基于S函数的新型变步长inc算法不仅跟踪速度较快,而且在最大功率点处的跟踪也准确稳定。 展开更多
关键词 光伏发电 MPPT 变步长inc算法 s函数
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A Stochastic Optimal Control Theory to Model Spontaneous Breathing
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作者 Kyongyob Min 《Applied Mathematics》 2013年第11期1537-1546,共10页
Respiratory variables, including tidal volume and respiratory rate, display significant variability. The probability density function (PDF) of respiratory variables has been shown to contain clinical information and c... Respiratory variables, including tidal volume and respiratory rate, display significant variability. The probability density function (PDF) of respiratory variables has been shown to contain clinical information and can predict the risk for exacerbation in asthma. However, it is uncertain why this PDF plays a major role in predicting the dynamic conditions of the respiratory system. This paper introduces a stochastic optimal control model for noisy spontaneous breathing, and obtains a Shr&ouml;dinger’s wave equation as the motion equation that can produce a PDF as a solution. Based on the lobules-bronchial tree model of the lung system, the tidal volume variable was expressed by a polar coordinate, by use of which the Shr&ouml;dinger’s wave equation of inter-breath intervals (IBIs) was obtained. Through the wave equation of IBIs, the respiratory rhythm generator was characterized by the potential function including the PDF and the parameter concerning the topographical distribution of regional pulmonary ventilations. The stochastic model in this study was assumed to have a common variance parameter in the state variables, which would originate from the variability in metabolic energy at the cell level. As a conclusion, the PDF of IBIs would become a marker of neuroplasticity in the respiratory rhythm generator through Shr?dinger’s wave equation for IBIs. 展开更多
关键词 Biological Variability stochastic Processes Optimal stochastic Control Theory Probability Density function shr?dinger’s Wave Equation
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Nano-Electronic Simulation Software (NESS): A Novel Open-Source TCAD Simulation Environment
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作者 Cristina Medina-Bailon Tapas Dutta +4 位作者 Fikru Adamu-Lema Ali Rezaei Daniel Nagy Vihar P.Georgiev Asen Asenov 《Journal of Microelectronic Manufacturing》 2020年第4期21-31,共11页
This paper presents the latest status of the open source advanced TCAD simulator called Nano-Electronic Simulation Software(NESS)which is currently under development at the Device Modeling Group of the University of G... This paper presents the latest status of the open source advanced TCAD simulator called Nano-Electronic Simulation Software(NESS)which is currently under development at the Device Modeling Group of the University of Glasgow.NESS is designed with the main aim to provide an open,flexible,and easy to use simulation environment where users are able not only to perform numerical simulations but also to develop and implement new simulation methods and models.Currently,NESS is organized into two main components:the structure generator and a collection of different numerical solvers;which are linked to supporting components such as an effective mass extractor and materials database.This paper gives a brief overview of each of the components by describing their main capabilities,structure,and theory behind each one of them.Moreover,to illustrate the capabilities of each component,here we have given examples considering various device structures,architectures,materials,etc.at multiple simulation conditions.We expect that NESS will prove to be a great tool for both conventional as well as exploratory device research programs and projects. 展开更多
关键词 Integrated simulation Environment VARIABILITY DRIFT-DIFFUsION Quantum Correction Kubo-Greenwood Non-Equilibrium Green’s function
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Conceptual Problems in Bell’s Inequality and Quantum Entanglement
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作者 Yingqiu Gu 《Journal of Applied Mathematics and Physics》 2022年第7期2216-2231,共16页
The description of the microscopic world in quantum mechanics is very different from that in classical physics, and there are some points of view that are contrary to intuition and logic. The first is the problem of r... The description of the microscopic world in quantum mechanics is very different from that in classical physics, and there are some points of view that are contrary to intuition and logic. The first is the problem of reality;quantum mechanics believes the behavior of micro particles is random and jumping. The second is the loss of certainty;the conjugate physical variables of a system cannot be determined synchronously, they satisfy the Heisenberg uncertainty principle. The third is the non-local correlation. The measurement of one particle in the quantum entanglement pair will influence the state of the other entangled particle simultaneously. In this paper, some concepts related to quantum entanglement, such as EPR correlation, quantum entanglement correlation function, Bell’s inequality and so on, are analyzed in detail. Analysis shows that the mystery and confusion in quantum theory may be caused by the logical problems in its basic framework. Bell’s inequality is only a mathematical theorem, but its physical meaning is actually unclear. The Bell state of quantum entangled pair may not satisfy the dynamic equation of quantum theory, so it cannot describe the true state of microscopic particles. In this paper, the correct correlation functions of spin entanglement pair and photonic entanglement pair are strictly derived according to normal logic. Quantum theory is a more fundamental theory than classical mechanics, and they are not equal relation in logic. However, there are still some unreasonable contents in the framework of quantum theory, which need to be improved. In order to disclose the real relationship between quantum theory and classical mechanics, we propose some experiments which provide intuitionistic teaching materials for the new interpretation of quantum theory. 展开更多
关键词 Quantum Mechanics Interpretation Mathematical Foundation of Quantum Mechanics EPR Correlation Bohm’s Hidden variable Theory Quantum Entanglement Bell’s Inequality Quantum Correlation function schrödinger Equation Heisenberg Uncertainty Relation
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关于Hlder不等式和Minkowsi不等式
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作者 蔡同灵 《绵阳师范学院学报》 1998年第S2期18-23,共6页
给出一种方法证明Hlder不等式和Minkows kei不等式。
关键词 赫尔德不等式 明可夫斯基不等式 离散量 连续变量 连续函数
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