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Weak External Bisection of Some Graphs
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作者 Yumin Liu 《Journal of Applied Mathematics and Physics》 2024年第1期91-97,共7页
Let G be a graph. A bipartition of G is a bipartition of V (G) with V (G) = V<sub>1</sub> ∪ V<sub>2</sub> and V<sub>1</sub> ∩ V<sub>2</sub> = ∅. If a bipartition satis... Let G be a graph. A bipartition of G is a bipartition of V (G) with V (G) = V<sub>1</sub> ∪ V<sub>2</sub> and V<sub>1</sub> ∩ V<sub>2</sub> = ∅. If a bipartition satisfies ∥V<sub>1</sub>∣ - ∣V<sub>2</sub>∥ ≤ 1, we call it a bisection. The research in this paper is mainly based on a conjecture proposed by Bollobás and Scott. The conjecture is that every graph G has a bisection (V<sub>1</sub>, V<sub>2</sub>) such that ∀v ∈ V<sub>1</sub>, at least half minuses one of the neighbors of v are in the V<sub>2</sub>;∀v ∈ V<sub>2</sub>, at least half minuses one of the neighbors of v are in the V<sub>1</sub>. In this paper, we confirm this conjecture for some bipartite graphs, crown graphs and windmill graphs. 展开更多
关键词 Weak External bisection Bipartite Graph Windmill Graph
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COMPLETE KAHLER METRICS WITH POSITIVE HOLOMORPHIC SECTIONAL CURVATURES ON CERTAIN LINE BUNDLES(RELATED TO A COHOMOGENEITY ONE POINT OF VIEW ON A YAU CONJECTURE)
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作者 段晓曼 关庄丹 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期78-102,共25页
In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strateg... In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strategy to a famous Yau conjecture with a co-homogeneity one geometry. 展开更多
关键词 Kahler Metrics complete Riemannian metrics open complex manifolds holomorphic bisectional curvature C*bundle almost homogeneous manifolds
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The Chern-Ricci flow and holomorphic bisectional curvature 被引量:1
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作者 YANG XiaoKui 《Science China Mathematics》 SCIE CSCD 2016年第11期2199-2204,共6页
In this note, we show that on Hopf manifold S^(2n-1)×S^1, the non-negativity of the holomorphic bisectional curvature is not preserved along the Chern-Ricci flow.
关键词 Chern-Ricci flow holomorphic bisectional curvature Hopf manifolds
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Maximum Correntropy Criterion-Based UKF for Loosely Coupling INS and UWB in Indoor Localization
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作者 Yan Wang You Lu +1 位作者 Yuqing Zhou Zhijian Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2673-2703,共31页
Indoor positioning is a key technology in today’s intelligent environments,and it plays a crucial role in many application areas.This paper proposed an unscented Kalman filter(UKF)based on the maximum correntropy cri... Indoor positioning is a key technology in today’s intelligent environments,and it plays a crucial role in many application areas.This paper proposed an unscented Kalman filter(UKF)based on the maximum correntropy criterion(MCC)instead of the minimummean square error criterion(MMSE).This innovative approach is applied to the loose coupling of the Inertial Navigation System(INS)and Ultra-Wideband(UWB).By introducing the maximum correntropy criterion,the MCCUKF algorithm dynamically adjusts the covariance matrices of the system noise and the measurement noise,thus enhancing its adaptability to diverse environmental localization requirements.Particularly in the presence of non-Gaussian noise,especially heavy-tailed noise,the MCCUKF exhibits superior accuracy and robustness compared to the traditional UKF.The method initially generates an estimate of the predicted state and covariance matrix through the unscented transform(UT)and then recharacterizes the measurement information using a nonlinear regression method at the cost of theMCC.Subsequently,the state and covariance matrices of the filter are updated by employing the unscented transformation on the measurement equations.Moreover,to mitigate the influence of non-line-of-sight(NLOS)errors positioning accuracy,this paper proposes a k-medoid clustering algorithm based on bisection k-means(Bikmeans).This algorithm preprocesses the UWB distance measurements to yield a more precise position estimation.Simulation results demonstrate that MCCUKF is robust to the uncertainty of UWB and realizes stable integration of INS and UWB systems. 展开更多
关键词 Maximum correntropy criterion unscented Kalman filter inertial navigation system ULTRA-WIDEBAND bisecting kmeans clustering algorithm
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Bisection technique for designing synchronous parallel algorithms
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作者 王能超 《Science China Mathematics》 SCIE 1995年第5期635-640,共6页
A basic technique for designing synchronous parallel algorithms, the so-called bisection technique, is proposed. The basic pattern of designing parallel algorithms is described. The relationship between the designing ... A basic technique for designing synchronous parallel algorithms, the so-called bisection technique, is proposed. The basic pattern of designing parallel algorithms is described. The relationship between the designing idea and I Ching (principles of change) is discussed. 展开更多
关键词 SYNCHRONOUS parallel algorithm RECURSIVE doubling bisection TAIJI THINKING I Ching.
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基于iForest+Biscting K-means的驾驶风格辨识方法研究 被引量:3
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作者 邓天民 朱杰 +1 位作者 朱凯家 屈治华 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2021年第6期1-6,共6页
提出了一种基于iForest+Biscting K-means模型的客运驾驶员驾驶风格辨识方法。该方法针对在Bisceting Kmeans模型中,聚类质心严重影响聚类结果问题,采用iForest模型训练聚类中心候选集作为聚类质心集的方法加以改进。通过考察某城际客... 提出了一种基于iForest+Biscting K-means模型的客运驾驶员驾驶风格辨识方法。该方法针对在Bisceting Kmeans模型中,聚类质心严重影响聚类结果问题,采用iForest模型训练聚类中心候选集作为聚类质心集的方法加以改进。通过考察某城际客运线路30位客车职业驾驶员,在直线道路行驶工况下,90余天约400万条客车行驶数据开展模型验证。试验表明:在加速度标准差和超速倾向系数作为聚类指标的情况下,客运驾驶员驾驶风格聚类为谨慎型、普通型和激进型3类,其中谨慎型11人,普通型19人,激进型0人。 展开更多
关键词 交通工程 驾驶风格 Bisecting K-means算法 iForest算法 大数据
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Research on Key Technology of Efficient Production of Bovine Embryos
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作者 Guizhi TONG Hongguang WANG +3 位作者 Yongsheng HAN Xintao LI Weixia WANG Bin SONG 《Agricultural Biotechnology》 CAS 2020年第4期144-145,148,共3页
[Objectives]This study was conducted to explore the effects of three different splitting fluids on the bisection effects of bovine morulae and blastocysts.[Methods]With the help of a micromanipulator,the morulae and b... [Objectives]This study was conducted to explore the effects of three different splitting fluids on the bisection effects of bovine morulae and blastocysts.[Methods]With the help of a micromanipulator,the morulae and blastocysts that were routinely produced in the body from the 6 th to the 8 th d were divided into half-embryos in vitro to observe their development,and the half-embryos with a restored morphology and a blastocyst trophoblast were selected.[Results]The success rates of bisection of morulae in PBS+0.2 mol/L sucrose and PBS+5%PVP were significantly higher than that in PBS(P<0.05),and the values in the three liquids were 95.7%,97.2% and 50%,respectively,while the blastocyst development rates and of half-embryos and the pregnancy rates of transplantation were not significantly different(P>0.05).When blastocysts were bisected in PBS+0.2 mol/L sucrose and PBS+5% PVP,the success rates of bisection were significantly higher than that of PBS(P<0.05),and the values in the three liquids were 96.8%,95.5% and 50.0%,respectively,while the development rates of half-embryos and the pregnancy rates of transplantation were not significantly different(P>0.05).The development rate of half-embryos bisected from blastocysts was significantly higher than that of morulae.[Conclusions]This study improves the efficiency of bovine embryo bisection,which is beneficial to the application of embryo bisection technology in cattle breeding. 展开更多
关键词 CATTLE Embryo bisection Blastocyst development rate
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基于随机数三角阵映射的高维大数据二分聚类初始中心高效鲁棒生成算法 被引量:4
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作者 李旻 何婷婷 《电子与信息学报》 EI CSCD 北大核心 2021年第4期948-955,共8页
Bisecting K-means算法通过使用一组初始中心对分割簇,得到多个二分聚类结果,然后从中选优以减轻局部最优收敛问题对算法性能的不良影响。然而,现有的随机采样初始中心对生成方法存在效率低、稳定性差、缺失值等不同问题,难以胜任大数... Bisecting K-means算法通过使用一组初始中心对分割簇,得到多个二分聚类结果,然后从中选优以减轻局部最优收敛问题对算法性能的不良影响。然而,现有的随机采样初始中心对生成方法存在效率低、稳定性差、缺失值等不同问题,难以胜任大数据聚类场景。针对这些问题,该文首先创建出了初始中心对组合三角阵和初始中心对编号三角阵,然后通过建立两矩阵中元素及元素位置间的若干映射,从而实现了一种从随机整数集合中生成二分聚类初始中心对的线性复杂度算法。理论分析与实验结果均表明,该方法的时间效率及效率稳定性均明显优于常用的随机采样方法,特别适用于高维大数据聚类场景。 展开更多
关键词 Bisecting K-means 初始中心生成 三角矩阵映射 随机整数 高维大数据聚类 线性算法
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A Kernel Clustering Algorithm for Fast Training of Support Vector Machines
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作者 刘笑嶂 冯国灿 《Journal of Donghua University(English Edition)》 EI CAS 2011年第1期53-56,共4页
A new algorithm named kernel bisecting k-means and sample removal(KBK-SR) is proposed as sampling preprocessing for support vector machine(SVM) training to improve the efficiency.The proposed algorithm tends to quickl... A new algorithm named kernel bisecting k-means and sample removal(KBK-SR) is proposed as sampling preprocessing for support vector machine(SVM) training to improve the efficiency.The proposed algorithm tends to quickly produce balanced clusters of similar sizes in the kernel feature space,which makes it efficient and effective for reducing training samples.Theoretical analysis and experimental results on three UCI real data benchmarks both show that,with very short sampling time,the proposed algorithm dramatically accelerates SVM sampling and training while maintaining high test accuracy. 展开更多
关键词 support vector machines(SVMs) sample reduction topdown hierarchical clustering kernel bisecting k-means
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Video Summarization Approach Based on Binary Robust Invariant Scalable Keypoints and Bisecting K-Means
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作者 Sameh Zarif Eman Morad +3 位作者 Khalid Amin Abdullah Alharbi Wail S.Elkilani Shouze Tang 《Computers, Materials & Continua》 SCIE EI 2024年第3期3565-3583,共19页
Due to the exponential growth of video data,aided by rapid advancements in multimedia technologies.It became difficult for the user to obtain information from a large video series.The process of providing an abstract ... Due to the exponential growth of video data,aided by rapid advancements in multimedia technologies.It became difficult for the user to obtain information from a large video series.The process of providing an abstract of the entire video that includes the most representative frames is known as static video summarization.This method resulted in rapid exploration,indexing,and retrieval of massive video libraries.We propose a framework for static video summary based on a Binary Robust Invariant Scalable Keypoint(BRISK)and bisecting K-means clustering algorithm.The current method effectively recognizes relevant frames using BRISK by extracting keypoints and the descriptors from video sequences.The video frames’BRISK features are clustered using a bisecting K-means,and the keyframe is determined by selecting the frame that is most near the cluster center.Without applying any clustering parameters,the appropriate clusters number is determined using the silhouette coefficient.Experiments were carried out on a publicly available open video project(OVP)dataset that contained videos of different genres.The proposed method’s effectiveness is compared to existing methods using a variety of evaluation metrics,and the proposed method achieves a trade-off between computational cost and quality. 展开更多
关键词 BRISK bisecting K-mean video summarization keyframe extraction shot detection
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基于共词分析的文本主题词聚类与主题发现 被引量:33
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作者 王小华 徐宁 谌志群 《情报科学》 CSSCI 北大核心 2011年第11期1621-1624,共4页
文本主题检测可以很好的挖掘海量信息中的关键因子,本文主要通过基于共词分析方法对文本主题词进行聚类从而发现当前的主题,首先通过停用词过滤和TF-IDF关键词提取技术提取出主题词串,然后构建共词矩阵,最后通过Bisecting K-means算法... 文本主题检测可以很好的挖掘海量信息中的关键因子,本文主要通过基于共词分析方法对文本主题词进行聚类从而发现当前的主题,首先通过停用词过滤和TF-IDF关键词提取技术提取出主题词串,然后构建共词矩阵,最后通过Bisecting K-means算法对主题词串进行聚类分析,从而发现主题。实验结果表明,该方法对热点主题提取有一定的效果。 展开更多
关键词 共词分析 TF-IDF 共词矩阵 Bisecting K-MEANS 主题
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基于用户浏览行为的兴趣识别管理模型 被引量:17
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作者 刘洪伟 高鸿铭 +2 位作者 陈丽 詹明君 梁周扬 《数据分析与知识发现》 CSSCI CSCD 北大核心 2018年第2期74-85,共12页
【目的】了解用户在线购物中的兴趣需求变化有利于个性化推荐。本文提出结合用户浏览行为分析的隐式动态兴趣识别和管理模型。【方法】通过三阶段实验构造用户点击流数据,以天猫和淘宝网页功能键为数据粒度对页面分类,再采用Bisecting K... 【目的】了解用户在线购物中的兴趣需求变化有利于个性化推荐。本文提出结合用户浏览行为分析的隐式动态兴趣识别和管理模型。【方法】通过三阶段实验构造用户点击流数据,以天猫和淘宝网页功能键为数据粒度对页面分类,再采用Bisecting K-means聚类算法进行兴趣状态挖掘,最后总结归纳兴趣与行为的特征映射。【结果】用户隐式兴趣存在4种状态:关注、理解信息、态度和购买意图,在态度和购买意图状态下,更倾向于产生购买;在不同状态的浏览路径特征有所差异。【局限】未添加网页广告促销等非结构化数据进行分析。【结论】从实时动态兴趣的角度,对购物决策中兴趣的状态进行验证挖掘,拓展动态兴趣研究;为电商网站管理用户行为提供了一个实现动态个性化推荐的视角。 展开更多
关键词 隐式兴趣 点击流 Bisecting K-MEANS算法
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Residual-based a posteriori error estimates of nonconforming finite element method for elliptic problems with Dirac delta source terms 被引量:4
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作者 DU ShaoHong XIE XiaoPing 《Science China Mathematics》 SCIE 2008年第8期1440-1460,共21页
Two residual-based a posteriori error estimators of the nonconforming Crouzeix-Raviart element are derived for elliptic problems with Dirac delta source terms.One estimator is shown to be reliable and efficient,which ... Two residual-based a posteriori error estimators of the nonconforming Crouzeix-Raviart element are derived for elliptic problems with Dirac delta source terms.One estimator is shown to be reliable and efficient,which yields global upper and lower bounds for the error in piecewise W1,p seminorm.The other one is proved to give a global upper bound of the error in Lp-norm.By taking the two estimators as refinement indicators,adaptive algorithms are suggested,which are experimentally shown to attain optimal convergence orders. 展开更多
关键词 Crouzeix-Raviart element NONCONFORMING FEM a POSTERIORI error ESTIMATOR longest edge bisection
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基于汉英词性组合的短语级平行语料类别知识挖掘研究 被引量:1
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作者 王东波 韩普 +1 位作者 沈耕宇 沈思 《图书情报工作》 CSSCI 北大核心 2013年第11期106-111,145,共7页
基于通过具体实验确定的Bisecting K-means聚类和Lemmatization形态变换算法,在汉英短语级人文社会科学平行语料基础上,尝试进行类别知识挖掘的实验。在中文社会科学引文索引(CSSCI)的类别和标题知识基础上,完成对汉英语料的预处理,并... 基于通过具体实验确定的Bisecting K-means聚类和Lemmatization形态变换算法,在汉英短语级人文社会科学平行语料基础上,尝试进行类别知识挖掘的实验。在中文社会科学引文索引(CSSCI)的类别和标题知识基础上,完成对汉英语料的预处理,并分析名词、动词和形容词的分布状况。在名词、动词和形容词等词性的组合基础上,对比不同词性组合的效果并确定最优的词性组合类别知识挖掘模型。 展开更多
关键词 词性组合Bisecting K-means汉英平行语料库 类别知识
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Optimized third-order force-gradient symplectic algorithms 被引量:3
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作者 LI Rong & WU Xin School of Science,Nanchang University,Nanchang 330031,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第9期1600-1609,共10页
With the natural splitting of a Hamiltonian system into kinetic energy and potential energy,we construct two new optimal thirdorder force-gradient symplectic algorithms in each of which the norm of fourth-order trunca... With the natural splitting of a Hamiltonian system into kinetic energy and potential energy,we construct two new optimal thirdorder force-gradient symplectic algorithms in each of which the norm of fourth-order truncation errors is minimized.They are both not explicitly superior to their no-optimal counterparts in the numerical stability and the topology structure-preserving,but they are in the accuracy of energy on classical problems and in one of the energy eigenvalues for one-dimensional time-independent Schrdinger equations.In particular,they are much better than the optimal third-order non-gradient symplectic method.They also have an advantage over the fourth-order non-gradient symplectic integrator. 展开更多
关键词 SYMPLECTIC INTEGRATORS SYMPLECTIC scheme-shooting METHOD celestial mechanics time-independent Schrdinger equation energy eigenvalues numerical stability bisection METHOD topological structure
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基于英汉双语短语级平行语料的类别知识挖掘研究 被引量:1
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作者 王东波 韩普 +1 位作者 沈思 魏向清 《现代图书情报技术》 CSSCI 北大核心 2012年第11期40-46,共7页
在已有聚类算法的基础上,基于英汉双语短语级人文社会科学平行语料,进行类别知识挖掘的实验。根据实验数据并结合具体的研究需求,确定相应的聚类算法和英语形态转换的算法。通过对汉语、英语和英汉双语词汇级知识聚类的性能进行对比,确... 在已有聚类算法的基础上,基于英汉双语短语级人文社会科学平行语料,进行类别知识挖掘的实验。根据实验数据并结合具体的研究需求,确定相应的聚类算法和英语形态转换的算法。通过对汉语、英语和英汉双语词汇级知识聚类的性能进行对比,确定英汉双语词汇特征的性能优于单语。获取的类别知识可以直接应用到知识库、机器翻译模型的构建中,同时探究英汉两种词汇在类别知识获取过程中具体表现。 展开更多
关键词 CSSCI英汉双语短语级平行语料Bisecting K—means Clustering算法类别知识
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Immortal solution of the Ricci flow 被引量:1
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作者 RUAN Qihua & CHEN Zhihua Department of Applied Mathematics, Tongji University, Shanghai 200092, China Department of Mathematics, Putian College, Putian 351100, China 《Science China Mathematics》 SCIE 2005年第z1期217-224,共8页
For any complete noncompact Kahler manifold with nonnegative and bounded holomorphic bisectional curvature, we provide the necessary and sufficient condition for the immortal solution to the Ricci flow.
关键词 RICCI flow IMMORTAL solution HOLOMORPHIC bisectional curvature.
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An extension of Mok's theorem on the generalized Frankel conjecture
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作者 HuiLing Gu ZhuHong Zhang 《Science China Mathematics》 SCIE 2010年第5期216-227,共12页
In this paper,we will give an extension of Mok's theorem on the generalized Frankel conjecture under the condition of the orthogonal holomorphic bisectional curvature.
关键词 Khler RICCI flow orthogonal HOLOMORPHIC bisectional CURVATURE first CHERN class
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Full friendly index sets of mCn
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作者 Yurong JI Jinmeng LIU +1 位作者 Yujie BAI Shufei WU 《Frontiers of Computer Science》 SCIE EI CSCD 2022年第3期95-99,共5页
Let G be a connected simple graph with vertex set V(G)and edge set E(G).A binary vertex labeling f:V(G)→Z2,is said to be friendly if the number of vertices with different labels differs by at most one.Each vertex fri... Let G be a connected simple graph with vertex set V(G)and edge set E(G).A binary vertex labeling f:V(G)→Z2,is said to be friendly if the number of vertices with different labels differs by at most one.Each vertex friendly labeling/induces an edge labeling f*E(G)→Z2,defined by f*(xy)=f(x)+f(y)for each xy∈E(G).Let er(i)=\{e∈E(G):f*(e)=i}|.The full friendly index set of G,denoted by FFI(G),is the set{ef*(1)-ep(0):f is friendly}.In this paper,we determine the full friendly index set of a family of cycle union graphs which are edge subdivisions of P2×Pn. 展开更多
关键词 vertex labeling friendly labeling full friendly index set PARTITION bisection
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基于VSM和Bisecting K-means聚类的新闻推荐方法 被引量:16
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作者 袁仁进 陈刚 +1 位作者 李锋 魏双建 《北京邮电大学学报》 EI CAS CSCD 北大核心 2019年第1期114-119,共6页
针对海量新闻数据给用户带来的困扰,为提升用户阅读新闻的个性化体验,提出了融合向量空间模型和Bisecting K-means聚类的新闻推荐方法.首先进行新闻文本向量化,使用向量空间模型和TF-IDF算法构建出新闻特征向量;采用Bisecting K-means... 针对海量新闻数据给用户带来的困扰,为提升用户阅读新闻的个性化体验,提出了融合向量空间模型和Bisecting K-means聚类的新闻推荐方法.首先进行新闻文本向量化,使用向量空间模型和TF-IDF算法构建出新闻特征向量;采用Bisecting K-means聚类算法对新闻特征向量集进行聚类;然后将已聚类的新闻集分为训练集和测试集,根据训练集构建"用户—新闻类别—新闻"三层层次结构的用户兴趣模型;最后采用余弦相似度方法得出新闻推荐结果,并与测试集进行对比分析.实验以基于用户的协同过滤算法、基于物品的协同过滤算法、结合向量空间模型和K-means聚类的推荐方法为基准,实验结果表明,该方法具有可行性,在准确率、召回率和F值上都有所提高. 展开更多
关键词 个性化推荐 向量空间模型 Bisecting K-MEANS聚类算法 用户兴趣模型
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