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模糊K-Harmonic Means聚类算法 被引量:6
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作者 赵恒 杨万海 张高煜 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2005年第4期603-606,638,共5页
对K-HarmonicMeans算法进行扩展,考虑到数据点对不同类的隶属关系,将模糊的概念应用到聚类中,提出了模糊K-HarmonicMeans算法,推导出聚类中心和模糊隶属度的迭代公式.在中心迭代聚类算法统一框架的基础上,推导出FKHM算法聚类中心的条件... 对K-HarmonicMeans算法进行扩展,考虑到数据点对不同类的隶属关系,将模糊的概念应用到聚类中,提出了模糊K-HarmonicMeans算法,推导出聚类中心和模糊隶属度的迭代公式.在中心迭代聚类算法统一框架的基础上,推导出FKHM算法聚类中心的条件概率表达式以及在迭代过程中的数据加权函数表达式.最后,用Folkes&Mallows指标对聚类结果进行评价.实验表明,模糊K-HarmonicMeans(KHM)算法在聚类对于初值不敏感的同时提高了聚类结果的精确度,达到较好的聚类效果. 展开更多
关键词 模糊K—harmonic means聚类 聚类中心 条件概率 Folkes & Mallows指标
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基于模糊K-harmonic means的谱聚类算法 被引量:7
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作者 汪中 刘贵全 陈恩红 《智能系统学报》 2009年第2期95-99,共5页
谱聚类作为一种有效的方法广泛应用于机器学习.通过分析谱聚类初始化敏感的实质,引入对初值不敏感的模糊K-harmonic means算法来克服这一缺点,提出一种基于模糊K-harmonic means的谱聚类算法(FKHM-SC).与传统谱聚类算法以及对初值敏感的... 谱聚类作为一种有效的方法广泛应用于机器学习.通过分析谱聚类初始化敏感的实质,引入对初值不敏感的模糊K-harmonic means算法来克服这一缺点,提出一种基于模糊K-harmonic means的谱聚类算法(FKHM-SC).与传统谱聚类算法以及对初值敏感的K-means、FCM算法相比,改进算法不仅可以识别有挑战性的人工数据,并且可以得到稳定的聚类中心和聚类结果,同时提高了聚类的精确度.实验结果表明了该算法的有效性和可行性. 展开更多
关键词 谱聚类 模糊K-harmonic meanS 初始化敏感 聚类中心
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基于k-Harmonic means聚类分析的物流中心选址模型研究 被引量:3
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作者 李强 赵茂先 杨龙飞 《物流技术》 2009年第11期87-89,94,共4页
通过对传统物流选址模型运输成本的讨论,运用k-Harmonic means聚类分析方法对传统物流选址模型中运输费用进行重新构建,将以往的辐射状点对点送货路径替换为更贴近实际的连续圈式送货路线,克服了传统模型不符合实际情况的弊端,并通过较... 通过对传统物流选址模型运输成本的讨论,运用k-Harmonic means聚类分析方法对传统物流选址模型中运输费用进行重新构建,将以往的辐射状点对点送货路径替换为更贴近实际的连续圈式送货路线,克服了传统模型不符合实际情况的弊端,并通过较大规模的数值实验验证了方法的优越性。 展开更多
关键词 聚类 物流中心选址 k-harmonic meanS
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基于双层规划和K-Harmonic means聚类分析的学校选址研究
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作者 岳金辉 李强 《山东理工大学学报(自然科学版)》 CAS 2011年第2期6-10,共5页
学校选址是教育投资的首要环节,依据义务教育的强制性、免费性、普及性和均衡性等特点,建立了学校选址问题的整数线性双层规划模型(ILBP)和无容量限制的单层模型(UFLP).运用K-Harmonic means聚类分析方法对UFLP中的交通费用进行重新构建... 学校选址是教育投资的首要环节,依据义务教育的强制性、免费性、普及性和均衡性等特点,建立了学校选址问题的整数线性双层规划模型(ILBP)和无容量限制的单层模型(UFLP).运用K-Harmonic means聚类分析方法对UFLP中的交通费用进行重新构建,并通过较大规模的数值实验验证了该方法的优越性. 展开更多
关键词 学校选址 双层规划 K-harmonic means聚类分析
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THE SCHUR CONVEXITY OF GINI MEAN VALUES IN THE SENSE OF HARMONIC MEAN 被引量:4
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作者 夏卫锋 褚玉明 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1103-1112,共10页
We prove that the Gini mean values S(a,b; x,y) are Schur harmonic convex with respect to (x,y)∈(0,∞)×(0,∞) if and only if (a, b) ∈{(a, b):a≥0,a ≥ b,a+b+1≥0}∪{(a,b):b≥0,b≥a,a+b+1≥0} ... We prove that the Gini mean values S(a,b; x,y) are Schur harmonic convex with respect to (x,y)∈(0,∞)×(0,∞) if and only if (a, b) ∈{(a, b):a≥0,a ≥ b,a+b+1≥0}∪{(a,b):b≥0,b≥a,a+b+1≥0} and Schur harmonic concave with respect to (x,y) ∈ (0,∞)×(0,∞) if and only if (a,b)∈{(a,b):a≤0,b≤0,a|b|1≤0}. 展开更多
关键词 Gini mean values Schur convex Schur harmonic convex
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On the Weyl’s Lemma for Triharmonic Functions
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作者 ZHENG Run-jie ZENG Jia-min FANG Yi 《Chinese Quarterly Journal of Mathematics》 2024年第3期288-294,共7页
In this paper,by choosing some appropriate test functions,we prove the Weyl’s lemma for triharmonic functions based on the new type of mean value formulas.
关键词 Weyl’s lemma harmonic functions Triharmonic functions Test functions mean value formulas
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Using Harmonic Mean to Solve Multi-Objective Linear Programming Problems 被引量:3
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作者 Nejmaddin A. Sulaiman Rebaz B. Mustafa 《American Journal of Operations Research》 2016年第1期25-30,共6页
In this paper, we have suggested a new technique to transform multi-objective linear programming problem (MOLPP) to the single objective linear programming problem by using Harmonic mean for values of function and an ... In this paper, we have suggested a new technique to transform multi-objective linear programming problem (MOLPP) to the single objective linear programming problem by using Harmonic mean for values of function and an algorithm is suggested for its solution, the computer application of algorithm has been demonstrated by solving some numerical examples. We have used some other techniques, such as (sen, arithmetic mean, median) to solve the same problems, the results in Table 3 indicate that the new technique in general is promising. 展开更多
关键词 MOLPP harmonic mean
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Research on Methods of Parameter Estimation in Combining Forecasting Based on Harmonic Mean
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作者 Wang Yingming Dept. of Automation, Xiamen University, 361005, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第1期2-8,共7页
Two kinds of parameter estimation methods (I) and (II) of combining forecasting based on harmontic mean are proposed and compared through a lot of simulation forecasting examples. A very helpful conclusion is obtained... Two kinds of parameter estimation methods (I) and (II) of combining forecasting based on harmontic mean are proposed and compared through a lot of simulation forecasting examples. A very helpful conclusion is obtained, which can lay solid foundations for correct application of the above methods. 展开更多
关键词 harmonic mean Combining forecasting Parameter estimation.
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A Study of Multi-Node and Dual-Hop Collaborative Communication Performance Based on Harmonic Mean Method
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作者 Tingting YANG Shufang ZHANG 《Communications and Network》 2009年第1期42-45,共4页
Closed form expressions for the PDF and MGF of the harmonic mean of two independent exponential variates are cited and derived, and then applied to study the performance of cellular multi-node and dual-hop cooperative... Closed form expressions for the PDF and MGF of the harmonic mean of two independent exponential variates are cited and derived, and then applied to study the performance of cellular multi-node and dual-hop cooperative communication systems with non-regenerative relays over flat Rayleigh fading channels. We derive the probability density function (PDF) and asymptotic symbol error rate (SER) expression with MRC scheme. Then we use Matlab to simulate the performance. 展开更多
关键词 harmonic mean COOPERATIVE communication MULTI-NODE dual-hop MGF
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模糊K-Harmonic-Kohonen网络的FTIR光谱数据聚类分析 被引量:4
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作者 陈勇 郭云柱 +3 位作者 王威 武小红 贾红雯 武斌 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2023年第1期268-272,共5页
食品的品种不同则其含有营养成分和功效存在差异,得到的傅里叶变换红外光谱也存在差异。为了准确的实现品种分类,设计了一种将傅里叶变换红外光谱与模糊聚类分析方法相结合的品种鉴别方法。在模糊Kohonen聚类网络(FKCN)基础上将模糊K调... 食品的品种不同则其含有营养成分和功效存在差异,得到的傅里叶变换红外光谱也存在差异。为了准确的实现品种分类,设计了一种将傅里叶变换红外光谱与模糊聚类分析方法相结合的品种鉴别方法。在模糊Kohonen聚类网络(FKCN)基础上将模糊K调和聚类(FKHM)引入到Kohonen聚类网络的学习速率和更新策略中,提出了模糊K-Harmonic-Kohonen网络(FKHKCN)算法。FKHKCN利用模糊C均值(FCM)聚类的模糊隶属度计算其学习速率,以FKHM的聚类中心为基础通过推导计算得到FKHKCN的聚类中心,可以解决模糊Kohonen聚类网络方法对于初始类中心敏感而导致聚类结果不稳定的问题。FKHKCN作为一种模糊聚类算法,可实现傅里叶变换红外光谱数据的聚类分析。采用三种数据集:(1)采集产自四川的三种茶叶(优质和劣质的乐山竹叶青以及峨眉山毛峰)作为实验样本,样本总数为96。(2)两个品种(robusta和arabica)的咖啡样本。(3)三个品种(鸡肉、猪肉和火鸡)的肉类样本。首先对三个光谱数据集进行预处理,利用多元散射校正降低茶叶样本原始光谱数据集的散射影响,使用Savitzky-Golay减少噪声对肉类和咖啡这两个光谱数据集的影响。再利用主成分分析将高维的三种光谱数据集压缩至低维。然后采用线性判别分析进行特征提取,将光谱数据投影到求得的鉴别向量上。最后分别采用FCM,FKCN和FKHKCN对茶叶、肉类和咖啡进行判别。最终结果如下:FCM,FKCN和FKHKCN对茶叶品种的聚类准确率分别为90.91%,90.91%和93.94%;对肉类品种的聚类准确率分别为90.83%,0.00%和92.50%;对咖啡品种的聚类准确率分别为89.17%,89.17%和90.83%。以上实验结果表明:采用傅里叶红外光谱技术结合主成分分析、线性判别分析和FKHKCN的方法能够较有效地对食品的品种进行鉴别,且鉴别准确率比FCM和FKCN更高,聚类结果更稳定。 展开更多
关键词 傅里叶变换红外光谱 模糊K调和均值聚类 多元散射校正 模糊KOHONEN聚类网络 聚类分析
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Several Hermite-Hadamard Type Inequalities for Harmonically Convex Functions in the Second Sense with Applications 被引量:1
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作者 Wang Wen Yang Shi-guo Liu Xue-ying 《Communications in Mathematical Research》 CSCD 2016年第2期105-110,共6页
In this paper, we first introduce the concept "harmonically convex functions" in the second sense and establish several Hermite-Hadamard type inequalities for harmonically convex functions in the second sense. Final... In this paper, we first introduce the concept "harmonically convex functions" in the second sense and establish several Hermite-Hadamard type inequalities for harmonically convex functions in the second sense. Finally, some applications to special mean are shown. 展开更多
关键词 Hermite-Hadamard's inequality harmonically convex function mean inequality
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ADAPTIVE FEED-FORWARD COMPENSATOR FOR HARMONIC CANCELLATION IN ELECTRO-HYDRAULIC SERVO SYSTEM 被引量:3
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作者 YAO Jianjun WANG Liquan +2 位作者 JIANG Hongzhou WU Zhenshun HAN Junwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期77-81,共5页
Since the dead zone phenomenon occurs in electro-hydraulic servo system, the output of the system corresponding to a sinusoidal input contains higher harmonic besides the fundamental input, which causes harmonic disto... Since the dead zone phenomenon occurs in electro-hydraulic servo system, the output of the system corresponding to a sinusoidal input contains higher harmonic besides the fundamental input, which causes harmonic distortion of the output signal. The method for harmonic cancellation based on adaptive filter is proposed. The task is accomplished by generating reference signals with frequency that should be eliminated from the output. The reference inputs are weighted by the adaptive filter in such a way that it closely matches the harmonic. The output of the adaptive filter is a harmonic replica and is injected to the fundamental signal such that the output harmonic is cancelled leaving the desired signal alone, and the total harmonic distortion (THD) is greatly reduced. The weights of filter are adjusted on-line according to the control error by using least-mean-square (LMS) algorithm. Simulation results performed with a hydraulic system demonstrate the efficiency and validity of the proposed adaptive feed-forward compensator (AFC) control scheme 展开更多
关键词 Adaptive filter Adaptive feed-forward compensator Least-mean-square algorithm Dead zone harmonic distortion
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EXISTENCE AND NONEXISTENCE OF SOLUTIONS FOR A HARMONIC EQUATION WITH CRITICAL NONLINEARITY
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作者 Kamal OULD BOUH 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1305-1316,共12页
This paper is concerned with the harmonic equation(P;) : ?u = 0, u > 0 in B;and ?u/?ν+((n-2)/2)u =((n-2)/2) Ku;on S;where B;is the unit ball in R;, n ≥ 4 with Euclidean metric g;, ?B;= S;is its boundary, K is... This paper is concerned with the harmonic equation(P;) : ?u = 0, u > 0 in B;and ?u/?ν+((n-2)/2)u =((n-2)/2) Ku;on S;where B;is the unit ball in R;, n ≥ 4 with Euclidean metric g;, ?B;= S;is its boundary, K is a function on S;and ε is a small positive parameter. We construct solutions of the subcritical equation(P;) which blow up at one critical point of K. We give also a sufficient condition on the function K to ensure the nonexistence of solutions for(P;) which blow up at one point. Finally, we prove a nonexistence result of single peaked solutions for the supercritical equation(P;). 展开更多
关键词 variational problem critical points harmonic equation mean curvature critical exponent
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HARNACK AND MEAN VALUE INEQUALITIES ON GRAPHS
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作者 Yong LIN Hongye SONG 《Acta Mathematica Scientia》 SCIE CSCD 2018年第6期1751-1758,共8页
We prove a Harnack inequality for positive harmonic functions on graphs whichis similar to a classical result of Yau on Riemannian manifolds. Also, we prove a mean valueinequality of nonnegative subharmonic functions ... We prove a Harnack inequality for positive harmonic functions on graphs whichis similar to a classical result of Yau on Riemannian manifolds. Also, we prove a mean valueinequality of nonnegative subharmonic functions on graphs. 展开更多
关键词 harmonic function subharmonic function Harnack inequality mean valueinequality GRAPH
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An Elementary Proof of the Mean Inequalities
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作者 Ilhan M. Izmirli 《Advances in Pure Mathematics》 2013年第3期331-334,共4页
In this paper we will extend the well-known chain of inequalities involving the Pythagorean means, namely the harmonic, geometric, and arithmetic means to the more refined chain of inequalities by including the logari... In this paper we will extend the well-known chain of inequalities involving the Pythagorean means, namely the harmonic, geometric, and arithmetic means to the more refined chain of inequalities by including the logarithmic and identric means using nothing more than basic calculus. Of course, these results are all well-known and several proofs of them and their generalizations have been given. See [1-6] for more information. Our goal here is to present a unified approach and give the proofs as corollaries of one basic theorem. 展开更多
关键词 PYTHAGOREAN meanS ARITHMETIC mean GEOMETRIC mean harmonic mean Identric mean Logarithmic mean
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基于K-means算法的故障电弧检测方法 被引量:5
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作者 张帅 曲娜 +2 位作者 郑天芳 胡从强 李玮祯 《沈阳航空航天大学学报》 2022年第1期61-68,共8页
在正常工作和发生故障时对常见的电阻、电感串并联电路以及整流电路使用Cassie电弧模型进行simulink仿真,得到了不同电路和不同状态时的电流数据。在线性负载电路中,电弧故障电流具有明显的零休特征,但是非线性负载电路不具有此特征。... 在正常工作和发生故障时对常见的电阻、电感串并联电路以及整流电路使用Cassie电弧模型进行simulink仿真,得到了不同电路和不同状态时的电流数据。在线性负载电路中,电弧故障电流具有明显的零休特征,但是非线性负载电路不具有此特征。应用快速傅里叶算法进一步分析了其不同状态下的电流谐波变化。利用k-means聚类算法理论建立了电弧故障检测模型,将电流的奇数高次谐波占基波分量作为特征值带入算法,并通过70组数据对模型进行测试,测试结果证明了该模型的有效性。 展开更多
关键词 电弧故障 Cassie电弧模型 仿真分析 谐波分析 K-meanS算法
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基于k-means聚类的多谐波源责任划分方法研究
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作者 钱永亮 冯跃 +2 位作者 唐明淑 代瑞 郭成 《湖北电力》 2023年第5期121-126,共6页
针对谐波发射水平动态变化情况下的多谐波源责任划分问题,提出了一种基于k-means聚类的多谐波源责任划分方法。首先,以谐波电流幅值作为提取特征划分数据集合,对所要计算谐波责任的谐波源谐波电流数据进行k-means聚类处理;然后,分别对... 针对谐波发射水平动态变化情况下的多谐波源责任划分问题,提出了一种基于k-means聚类的多谐波源责任划分方法。首先,以谐波电流幅值作为提取特征划分数据集合,对所要计算谐波责任的谐波源谐波电流数据进行k-means聚类处理;然后,分别对每个数据集合进行相关性计算,得到各数据集合的谐波责任;最后,将各数据集合谐波责任加权求和,得到被观测时段内的谐波责任。经过实验表明,所提方法综合评估了被观测时间段内多谐波源的谐波责任,提高了谐波发射水平动态变化情况下多谐波源责任评估的有效性。 展开更多
关键词 动态变化 多谐波源 谐波责任划分 K-meanS聚类 相关性计算
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Geometric-Harmonic Mean and Characterizations of Some Mean-Values 被引量:2
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作者 刘证 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第2期217-220,共4页
The purpose of this paper is to provide a direct proof on the fact that the geometric-harmonic mean of any two positive numbers can be calculated by a first complete elliptical integral, and then to give new character... The purpose of this paper is to provide a direct proof on the fact that the geometric-harmonic mean of any two positive numbers can be calculated by a first complete elliptical integral, and then to give new characterizations of some mean-values. 展开更多
关键词 Arithmetic mean geometric mean harmonic mean geometric-harmonic mean first complete elliptic integral.
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一组加权平均值参数不等式 被引量:1
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作者 刘小宁 《高等数学研究》 2024年第1期66-68,共3页
采用变量替换,构建了一组加权平均值参数不等式,对Popovic不等式与Rado不等式进行了加权推广,加细了加权算术几何调和平均值不等式.
关键词 加权平均值 参数不等式 算术几何调和平均值不等式
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基于点多边形的混合坐标
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作者 苗苗 李亚娟 邓重阳 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2024年第7期1057-1064,共8页
为了构造非负且光滑的广义重心坐标,提出一种基于点多边形的混合坐标构建方法.首先将原多边形三角剖分,计算所有网格顶点的重心坐标,并确定每个网格顶点的点多边形;然后分别计算原多边形内点关于其所在三角形的点多边形的重心坐标与混... 为了构造非负且光滑的广义重心坐标,提出一种基于点多边形的混合坐标构建方法.首先将原多边形三角剖分,计算所有网格顶点的重心坐标,并确定每个网格顶点的点多边形;然后分别计算原多边形内点关于其所在三角形的点多边形的重心坐标与混合系数,根据以上计算结果得到混合坐标;最后使用迭代坐标或调和坐标计算网格顶点的重心坐标,用均值坐标和迭代坐标计算原多边形内点关于点多边形的重心坐标.数值实例采用多个多边形的等高线图,以及其不同重心坐标的非负区域、光滑性、纹理映射对比,表明所提方法具有良好的光滑性,且在任意多边形内部具有非负性. 展开更多
关键词 点多边形 均值坐标 迭代坐标 调和坐标 混合系数
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