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Generalizations of mixed weighted power mean inequality 被引量:1
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作者 马统一 张海娟 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期192-197,共6页
Tarnavas established mixed weighted power mean inequality in 1999. A separation of weighted power mean inequslity was derived in this paper. As its applications, some separations of other inequalities were given.
关键词 INEQUALITY power mean weighted power mean mixed weighted power mean difference function of mixed weightedpower mean separation
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Sharp power mean bounds for Seiffert mean 被引量:5
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作者 LI Yong-min WANG Miao-kun CHU Yu-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第1期101-107,共7页
In this paper, we find the greatest value p = log 2/(log Tr - log 2) = 1.53.- and the least value q -- 5/3 - 1.66.. such that the double inequality Mp(a,b) 〈 T(a,b) 〈 Mq(a,b) holds for all a, b 〉 0 with a #... In this paper, we find the greatest value p = log 2/(log Tr - log 2) = 1.53.- and the least value q -- 5/3 - 1.66.. such that the double inequality Mp(a,b) 〈 T(a,b) 〈 Mq(a,b) holds for all a, b 〉 0 with a # b. Here, Mp(a, b) and T(a, b) are the p-th power and Seiffertmeans of two positive numbers a and b, respectively. 展开更多
关键词 power mean Seiffert mean INEQUALITY
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On the Fourth Power Mean of Generalized Three-Term Exponential Sums 被引量:3
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作者 Xiancun DU Xiaoxue LI 《Journal of Mathematical Research with Applications》 CSCD 2015年第1期92-96,共5页
The main purpose of this paper is using estimates for trigonometric sums and properties of congruence to study the computation of one kind of fourth power mean of a generalized three-term exponential sum, and give an ... The main purpose of this paper is using estimates for trigonometric sums and properties of congruence to study the computation of one kind of fourth power mean of a generalized three-term exponential sum, and give an interesting identity for it. 展开更多
关键词 generalized three-term exponential sums fourth power mean IDENTITY
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On the Fourth Power Mean of Generalized Three-Term Exponential Sums 被引量:1
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作者 Huaning LIU Wanmei LI 《Journal of Mathematical Research with Applications》 CSCD 2017年第2期169-182,共14页
The computational problem of fourth power mean of generalized three-term exponential sums is studied by using the trigonometric identity and the properties of the reduced residue system. Some explicit formulas for the... The computational problem of fourth power mean of generalized three-term exponential sums is studied by using the trigonometric identity and the properties of the reduced residue system. Some explicit formulas for the fourth power mean of generalized three-term exponential sums under different conditions are given. 展开更多
关键词 generalized three-term exponential sum IDENTITY fourth power mean formula
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The Hybrid Power Mean Involving the Character Sum of Polynomials and a Sum Analogous to Kloosterman Sum
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作者 LU Xingxing ZHANG Wenpeng 《数学进展》 CSCD 北大核心 2024年第6期1199-1209,共11页
The main purpose of this paper is using the properties of the classical Gauss sum and the analytic methods to study the computational problem of one kind of hybrid power mean involving the character sum of polynomials... The main purpose of this paper is using the properties of the classical Gauss sum and the analytic methods to study the computational problem of one kind of hybrid power mean involving the character sum of polynomials and a sum analogous to Kloosterman sum mod p,an odd prime,and give two sharp asymptotic formulae for them. 展开更多
关键词 character sum of polynomials a sum analogous to Kloosterman sum hybrid power mean the classical Gauss sum analytic method asymptotic formula
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Sharps Bounds for Power Mean in Terms of Contraharmonic Mean
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作者 Zeid I. Almuhiameed 《Journal of Applied Mathematics and Physics》 2020年第7期1229-1235,共7页
In this research work, we consider the below inequalities: (1.1). The researchers attempt to find an answer as to what are the best possible parameters <i><i>&#945;</i></i>, <i><i&... In this research work, we consider the below inequalities: (1.1). The researchers attempt to find an answer as to what are the best possible parameters <i><i>&#945;</i></i>, <i><i>&#946;</i></i> that (1.1) can be held? The main tool is the optimization of some suitable functions that we seek to find out. Without loss of generality, we have assumed that <i>a</i> > <i>b</i> and let <img src="Edit_26c0f99b-93dd-48ff-acdb-f1c8047744f1.bmp" alt="" /> for 1) and <i>a</i> < <i>b</i>, <img src="Edit_15c32a7a-e9ae-41d3-8f49-c6b9c01c7ece.bmp" alt="" />(<i>t</i> small) for 2) to determine the condition for <i><i>&#945;</i></i> and <i><i>&#946;</i></i> to become <i>f</i>(<i>t</i>) ≤ 0 and <i>g</i>(<i>t</i>) ≥ 0. 展开更多
关键词 Sharps Bounds power mean Contraharmonic mean
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融合离群点检测与K-means的用电侧异常行为自动识别
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作者 陈普 刘仲 刘元强 《自动化应用》 2026年第2期170-172,共3页
针对用电侧异常行为自动识别中存在的错识和漏识问题,提出融合离群点检测与K-means的用电侧异常行为自动识别方法。通过对用电侧行为数据进行填补及标准化处理,实现对原始数据的预处理;通过对用电侧行为进行离群点检测,深入挖掘数据中... 针对用电侧异常行为自动识别中存在的错识和漏识问题,提出融合离群点检测与K-means的用电侧异常行为自动识别方法。通过对用电侧行为数据进行填补及标准化处理,实现对原始数据的预处理;通过对用电侧行为进行离群点检测,深入挖掘数据中的潜在规律,提取离散特征的数据点。利用K-means算法对检测出的时间离群点序列进行聚类,识别序列中的异常行为,实现融合离群点检测与K-means的用电侧异常行为自动识别。实验证明,所设计方法的错识率不超过1.5%,漏识率不超过1%,可实现对用电侧异常行为的自动识别。 展开更多
关键词 离群点检测 K-meanS 用电侧 异常行为 标准化
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基于DFT-DTW-k-means++与CNN-BiGRU电力数据降噪与负荷预测
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作者 王建文 靳松华 马菲 《微型电脑应用》 2026年第1期30-33,38,共5页
针对传统电力数据分析易受跨域信息干扰,导致跨域负荷预测精度低的问题,提出一种基于离散傅里叶变换—动态时间规整(DFT-DTW)-k-means++结合卷积神经网络—双向门控循环单元(CNN-BiGRU)的数据降噪与预测模型。采用DFT对电力负荷数据进... 针对传统电力数据分析易受跨域信息干扰,导致跨域负荷预测精度低的问题,提出一种基于离散傅里叶变换—动态时间规整(DFT-DTW)-k-means++结合卷积神经网络—双向门控循环单元(CNN-BiGRU)的数据降噪与预测模型。采用DFT对电力负荷数据进行降噪处理;采用k-means++算法对电力负荷数据进行聚类划分,并采用DTW对跨域的电力负荷数据进行度量;构建CNN-BiGRU的负荷预测模型对电力负荷进行预测。结果表明:采用DFT的降噪方法得到的时域信号更加明显;在随机森林回归等不同预测模型下,DFT-DTW-k-means++的数据划分方法的均方根误差值更低;相较于双向长短期记忆(BiLSTM)预测模型、支持向量回归预测模型等,所提出的预测模型的平均均方误差值为0.085,均低于其他预测模型。由此说明,所提出的模型可实现跨域负荷数据降噪,且可提高预测准确率,进而提升电力数据利用效果。 展开更多
关键词 深度学习 电力交易数据 k-means++算法 卷积神经网络—双向门控循环单元 电力负荷预测
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基于K-means聚类的汽车电动尾门防夹算法研究
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作者 戴华通 王立献 熊瑞斌 《汽车电器》 2026年第2期90-92,共3页
针对汽车电动尾门系统面临复杂工况容易发生防夹功能失效的问题,文章提出一种基于K-means聚类的电动尾门防夹检测算法。首先收集电动尾门在不同工况下正常运动中的霍尔反馈信号,建立基于K-means聚类的防夹特征模型。然后,在防夹检测阶... 针对汽车电动尾门系统面临复杂工况容易发生防夹功能失效的问题,文章提出一种基于K-means聚类的电动尾门防夹检测算法。首先收集电动尾门在不同工况下正常运动中的霍尔反馈信号,建立基于K-means聚类的防夹特征模型。然后,在防夹检测阶段根据待测数据与K组质心的距离估算夹持力并与阈值进行比较,判断是否发生夹持。测试结果表明:防夹功能在不同供电电压与停放角度下夹持力在50~80N之间,符合汽车行业标准的规定。 展开更多
关键词 电动尾门 防夹控制 K-meanS 机器学习
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On the Fourth Power Mean of the Character Sums Over Short Intervals 被引量:3
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作者 Wen Peng ZHANG Xiao Ying WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第1期153-164,共12页
The main purpose of this paper is to study the mean value properties of the character sums over the interval [1,p/8) by using the mean value theorems of the Dirichlet L-functions, and give an interesting mean value f... The main purpose of this paper is to study the mean value properties of the character sums over the interval [1,p/8) by using the mean value theorems of the Dirichlet L-functions, and give an interesting mean value formula for this study. 展开更多
关键词 character sums short intervals fourth power mean asymptotic formula
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On the Sixth Power Mean of the Two-term Exponential Sums 被引量:5
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作者 Wen Peng ZHANG Yuan Yuan MENG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2022年第3期510-518,共9页
The main purpose of this article is to study the calculating problem of the sixth power mean of the two-term exponential sums,and give an interesting calculating formula for it.At the same time,the paper also provides... The main purpose of this article is to study the calculating problem of the sixth power mean of the two-term exponential sums,and give an interesting calculating formula for it.At the same time,the paper also provides a new and effective method for the study of the high order power mean of the exponential sums. 展开更多
关键词 The two-term exponential sums the sixth power mean
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ON THE GENERAL k-TH KLOOSTERMAN SUMS AND ITS FOURTH POWER MEAN 被引量:2
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作者 LIUHONGYAN ZHANGWENPENG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2004年第1期97-102,共6页
The main purpose of this paper is to study the asymptotic property of the fourth power mean of the general k-th Kloosterman sums, and give an interesting asymptotic formula.
关键词 General k-th Kloosterman sums Fourth power mean Asymptotic for-mula
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On the Fourth Power Mean of the Generalized Quadratic Gauss Sums
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作者 Wen Peng ZHANG Xin LIN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第6期1037-1049,共13页
The main purpose of this paper is to use elementary methods and properties of the classical Gauss sums to study the computational problem of one kind of fourth power mean of the generalized quadratic Gauss sums mod q ... The main purpose of this paper is to use elementary methods and properties of the classical Gauss sums to study the computational problem of one kind of fourth power mean of the generalized quadratic Gauss sums mod q (a positive odd number), and give an exact computational formula for it. 展开更多
关键词 The generalized quadratic Gauss sums the fourth power mean analytic method computational formula
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On the Hybrid Power Mean Involving the Two-Term Exponential Sums and Polynomial Character Sums
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作者 Xingxing LV Xiaoxue LI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2020年第4期547-558,共12页
The main purpose of this paper is using the analytic method and the properties of trigonometric sums and character sums to study the computational problem of one kind hybrid power mean involving two-term exponential s... The main purpose of this paper is using the analytic method and the properties of trigonometric sums and character sums to study the computational problem of one kind hybrid power mean involving two-term exponential sums and polynomial character sums.Then the authors give some interesting calculating formulae for them. 展开更多
关键词 The two-term exponential sums Kloosterman sums Dirichlet character of polynomials Hybrid power mean IDENTITY
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Does Being a Big Power Mean Paying a Big Bill? Japan's UN funding proposal appears to disguise political motives
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作者 ZHOU YONGSHENG is a professor of China Foreign Affairs University 《Beijing Review》 2006年第14期13-,共1页
Japan, which is increasingly frustrated that it has not been granted a permanent seat on the UN Security Council, has found a new outlet of displeasure against the world body. On March 10, Japan proposed to the UN Gen... Japan, which is increasingly frustrated that it has not been granted a permanent seat on the UN Security Council, has found a new outlet of displeasure against the world body. On March 10, Japan proposed to the UN General Assembly budget committee, 展开更多
关键词 UN Does Being a Big power mean Paying a Big Bill Japan’s UN funding proposal appears to disguise political motives GDP Security
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The Fourth Power Mean of the General 3-dimensional Kloostermann Sums mod p 被引量:3
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作者 Wen Peng ZHANG Xing Xing LV 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2019年第3期369-377,共9页
The main purpose of this paper is using the analytic methods, the solutions of the congruence equation mod p and the properties of Gauss sums to study the computational problem of one kind fourth power mean of the gen... The main purpose of this paper is using the analytic methods, the solutions of the congruence equation mod p and the properties of Gauss sums to study the computational problem of one kind fourth power mean of the general 3-dimensional Kloostermann sums mod p, and give a sharp asymptotic formula for it. 展开更多
关键词 The general 3-dimensional Kloostermann SUMS the FOURTH power mean DIRICHLET CHARACTER ASYMPTOTIC FORMULA
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A Short-Term PV Power Forecasting Method Using a Hybrid Kmeans-GRA-SVR Model under Ideal Weather Condition 被引量:2
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作者 Jiemin Lin Haiming Li 《Journal of Computer and Communications》 2020年第11期102-119,共18页
With the continuous increase of solar penetration rate, it has brought challenges to the smooth operation of the power grid. Therefore, to make photovoltaic power generation not affect the smooth operation of the grid... With the continuous increase of solar penetration rate, it has brought challenges to the smooth operation of the power grid. Therefore, to make photovoltaic power generation not affect the smooth operation of the grid, accurate photovoltaic power prediction is required. And short-term forecasting is essential for the deployment of daily power generation plans. In this paper, A short-term photovoltaic power generation forecast method based on K-means++, grey relational analysis (GRA) and support vector regression (SVR) (Hybrid Kmeans-GRA-SVR, HKGSVR) was proposed. The historical power data was clustered through the multi-index K-means++ algorithm. And the similar days and the nearest neighbor similar day of the prediction day were selected by the GRA algorithm. Then, similar days and nearest neighbor similar days were used to train SVR to obtain an accurate photovoltaic power prediction model. Under ideal weather, the average values of MAE, RMSE, and R<sup>2</sup> were 0.8101 kW, 0.9608 kW, and 99.66%, respectively. The average computation time was 1.7487 s, which was significantly better than the SVR model. Thus, the demonstrated numerical results verify the effectiveness of the proposed model for short-term PV power prediction. 展开更多
关键词 Grey Relational Analysis K-means++ Nearest Neighbor Similar Day Photovoltaic power Support Vector Regression
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基于K-Means聚类算法的直流电网换流器故障自动化检测系统 被引量:1
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作者 翁子韵 《自动化与仪表》 2025年第4期86-90,共5页
直流电网换流器结构复杂、监测信号较多,为了自动从大量监测信号中筛选关键特征,准确识别电网换流器故障,设计基于K-Means聚类算法的直流电网换流器故障自动化检测系统。采集的各线路电压信号,采用改进主成分分析法将高维的监测信号数... 直流电网换流器结构复杂、监测信号较多,为了自动从大量监测信号中筛选关键特征,准确识别电网换流器故障,设计基于K-Means聚类算法的直流电网换流器故障自动化检测系统。采集的各线路电压信号,采用改进主成分分析法将高维的监测信号数据降维成少数几个主成分,作为反映线路电压信号的主要特征;通过改进K-Means聚类算法对所提取信号主成分特征进行分组归类,实现电网换流器故障信号分类检测。经测试,此系统对直流电网换流器单极故障、双极故障样本进行聚类识别后,识别结果的误差平方和最大值仅为0.02,可实现高精度的直流电网换流器故障自动化检测。 展开更多
关键词 主成分分析法 K-meanS聚类算法 直流电网 换流器 故障检测 自动化
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无蜂窝通感一体化系统用户调度与功率分配
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作者 王丹 何春梅 +1 位作者 郑少杰 黄烨霞 《无线电通信技术》 北大核心 2026年第1期52-61,共10页
随着6G技术推进,毫米波/太赫兹频段的超大带宽优势与传播损耗瓶颈并存,传统蜂窝架构问题催生无蜂窝网络架构。通感一体化(Integrated Sensing and Communication,ISAC)技术通过资源共享实现感知与通信协同,可优化波束成型与对准,使无蜂... 随着6G技术推进,毫米波/太赫兹频段的超大带宽优势与传播损耗瓶颈并存,传统蜂窝架构问题催生无蜂窝网络架构。通感一体化(Integrated Sensing and Communication,ISAC)技术通过资源共享实现感知与通信协同,可优化波束成型与对准,使无蜂窝ISAC系统成为未来通信重要趋势。当前多数用户调度算法仅限制用户连接接入点的最大数量,未结合用户实际需求动态调整连接数目,导致信道质量好的用户易占用多余接入点服务名额,造成资源浪费。鉴于用户需求的动态变化,依其需求灵活调整接入点连接数量,可有效提升资源利用效率。为此,提出一种创新的动态用户调度方案,采用改进的K-means++聚类算法,基于用户信道状态与实时业务需求实现接入点动态分配,设计了基于二分法的功率分配(Bisection Method-based Power Allocation,BM-PA)算法优化资源配置。仿真结果表明,所提方案最高可节省40.6%的接入点资源,提升了资源利用率;在保障通信质量的同时,用户平均感知信噪比(Signal to Noise Ratio,SNR)显著提升。 展开更多
关键词 无蜂窝通感一体化系统 用户调度 功率分配 K-means++ 基于二分法的功率分配算法
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A Hybrid K-Means-GRA-SVR Model Based on Feature Selection for Day-Ahead Prediction of Photovoltaic Power Generation
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作者 Jiemin Lin Haiming Li 《Journal of Computer and Communications》 2021年第11期91-111,共21页
In order to ensure that the large-scale application of photovoltaic power generation does not affect the stability of the grid, accurate photovoltaic (PV) power generation forecast is essential. A short-term PV power ... In order to ensure that the large-scale application of photovoltaic power generation does not affect the stability of the grid, accurate photovoltaic (PV) power generation forecast is essential. A short-term PV power generation forecast method using the combination of K-means++, grey relational analysis (GRA) and support vector regression (SVR) based on feature selection (Hybrid Kmeans-GRA-SVR, HKGSVR) was proposed. The historical power data were clustered through the multi-index K-means++ algorithm and divided into ideal and non-ideal weather. The GRA algorithm was used to match the similar day and the nearest neighbor similar day of the prediction day. And selected appropriate input features for different weather types to train the SVR model. Under ideal weather, the average values of MAE, RMSE and R2 were 0.8101, 0.9608 kW and 99.66%, respectively. And this method reduced the average training time by 77.27% compared with the standard SVR model. Under non-ideal weather conditions, the average values of MAE, RMSE and R2 were 1.8337, 2.1379 kW and 98.47%, respectively. And this method reduced the average training time of the standard SVR model by 98.07%. The experimental results show that the prediction accuracy of the proposed model is significantly improved compared to the other five models, which verify the effectiveness of the method. 展开更多
关键词 Feature Selection Grey Relational Analysis K-means++ Nearest Neighbor Similar Day Photovoltaic power Support Vector Regression
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