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A Pattern Classification Model for Vowel Data Using Fuzzy Nearest Neighbor
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作者 Monika Khandelwal Ranjeet Kumar Rout +4 位作者 Saiyed Umer Kshira Sagar Sahoo NZ Jhanjhi Mohammad Shorfuzzaman Mehedi Masud 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3587-3598,共12页
Classification of the patterns is a crucial structure of research and applications. Using fuzzy set theory, classifying the patterns has become of great interest because of its ability to understand the parameters. ... Classification of the patterns is a crucial structure of research and applications. Using fuzzy set theory, classifying the patterns has become of great interest because of its ability to understand the parameters. One of the problemsobserved in the fuzzification of an unknown pattern is that importance is givenonly to the known patterns but not to their features. In contrast, features of thepatterns play an essential role when their respective patterns overlap. In this paper,an optimal fuzzy nearest neighbor model has been introduced in which a fuzzifi-cation process has been carried out for the unknown pattern using k nearest neighbor. With the help of the fuzzification process, the membership matrix has beenformed. In this membership matrix, fuzzification has been carried out of the features of the unknown pattern. Classification results are verified on a completelyllabelled Telugu vowel data set, and the accuracy is compared with the differentmodels and the fuzzy k nearest neighbor algorithm. The proposed model gives84.86% accuracy on 50% training data set and 89.35% accuracy on 80% trainingdata set. The proposed classifier learns well enough with a small amount of training data, resulting in an efficient and faster approach. 展开更多
关键词 nearest neighbors fuzzy classification patterns recognition reasoning rule membership matrix
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Probability Distribution of China Aviation Network Nearest Neighbor Average Degree and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Guo Jianyuan 《Journal of Traffic and Transportation Engineering》 2023年第3期95-106,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of node nearest neighbor average degree of China aviation netwo... In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of node nearest neighbor average degree of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the nearest neighbor average degrees of nodes in China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the nearest neighbor average degree had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network nearest neighbor average degree normal probability distribution linear evolution trace
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Nearest Neighbor Average Degree of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Zhang Xiaoxuan 《Journal of Traffic and Transportation Engineering》 2023年第4期159-171,共13页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of Chi... In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of China aviation network in 1988, 1994, 2001, 2008 and 2015 were studied. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network. According to the statistical data, the node nearest neighbor average degree of China aviation network in 1988, 1994, 2001, 2008 and 2015 was calculated. Through regression analysis, it was found that the node degree had a negative exponential relationship with the nearest neighbor average degree, and the two parameters of the negative exponential relationship had linear evolution trace. 展开更多
关键词 China aviation network complex network node degree nearest neighbor average degree negative exponential relationship evolution trace.
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基于不规则区域划分方法的k-Nearest Neighbor查询算法 被引量:1
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作者 张清清 李长云 +3 位作者 李旭 周玲芳 胡淑新 邹豪杰 《计算机系统应用》 2015年第9期186-190,共5页
随着越来越多的数据累积,对数据处理能力和分析能力的要求也越来越高.传统k-Nearest Neighbor(k NN)查询算法由于其容易导致计算负载整体不均衡的规则区域划分方法及其单个进程或单台计算机运行环境的较低数据处理能力.本文提出并详细... 随着越来越多的数据累积,对数据处理能力和分析能力的要求也越来越高.传统k-Nearest Neighbor(k NN)查询算法由于其容易导致计算负载整体不均衡的规则区域划分方法及其单个进程或单台计算机运行环境的较低数据处理能力.本文提出并详细介绍了一种基于不规则区域划分方法的改进型k NN查询算法,并利用对大规模数据集进行分布式并行计算的模型Map Reduce对该算法加以实现.实验结果与分析表明,Map Reduce框架下基于不规则区域划分方法的k NN查询算法可以获得较高的数据处理效率,并可以较好的支持大数据环境下数据的高效查询. 展开更多
关键词 k-nearest Neighbor(k NN)查询算法 不规则区域划分方法 MAP REDUCE 大数据
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Face Recognition Based on Support Vector Machine and Nearest Neighbor Classifier 被引量:8
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作者 Zhang Yankun & Liu Chongqing Institute of Image Processing and Pattern Recognition, Shanghai Jiao long University, Shanghai 200030 P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第3期73-76,共4页
Support vector machine (SVM), as a novel approach in pattern recognition, has demonstrated a success in face detection and face recognition. In this paper, a face recognition approach based on the SVM classifier with ... Support vector machine (SVM), as a novel approach in pattern recognition, has demonstrated a success in face detection and face recognition. In this paper, a face recognition approach based on the SVM classifier with the nearest neighbor classifier (NNC) is proposed. The principal component analysis (PCA) is used to reduce the dimension and extract features. Then one-against-all stratedy is used to train the SVM classifiers. At the testing stage, we propose an al- 展开更多
关键词 Face recognition Support vector machine nearest neighbor classifier Principal component analysis.
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基于K-Nearest Neighbor和神经网络的糖尿病分类研究 被引量:6
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作者 陈真诚 杜莹 +3 位作者 邹春林 梁永波 吴植强 朱健铭 《中国医学物理学杂志》 CSCD 2018年第10期1220-1224,共5页
为实现糖尿病的早期筛查,提高对糖尿病分类的准确度,在研究有关糖尿病危险因素的基础上,增加糖化血红蛋白作为糖尿病早期筛查的特征之一。研究中选取与人类最为相似的食蟹猴作为研究对象,利用年龄、血压、腹围、BMI、糖化血红蛋白以及... 为实现糖尿病的早期筛查,提高对糖尿病分类的准确度,在研究有关糖尿病危险因素的基础上,增加糖化血红蛋白作为糖尿病早期筛查的特征之一。研究中选取与人类最为相似的食蟹猴作为研究对象,利用年龄、血压、腹围、BMI、糖化血红蛋白以及空腹血糖作为特征输入,将正常、糖尿病前期和糖尿病作为类别输出,利用K-Nearest Neighbor(KNN)和神经网络两种方法对其分类。发现在增加糖化血红蛋白作为分类特征之一时,KNN(K=3)和神经网络的分类准确率分别为81.8%和92.6%,明显高于没有这一特征时的准确率(68.1%和89.7%),KNN和神经网络都可以对食蟹猴数据进行分类和识别,起到早期筛查作用。 展开更多
关键词 糖尿病 糖化血红蛋白 空腹血糖 KNN 神经网络 食蟹猴
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FEW-NNN: A Fuzzy Entropy Weighted Natural Nearest Neighbor Method for Flow-Based Network Traffic Attack Detection 被引量:6
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作者 Liangchen Chen Shu Gao +2 位作者 Baoxu Liu Zhigang Lu Zhengwei Jiang 《China Communications》 SCIE CSCD 2020年第5期151-167,共17页
Attacks such as APT usually hide communication data in massive legitimate network traffic, and mining structurally complex and latent relationships among flow-based network traffic to detect attacks has become the foc... Attacks such as APT usually hide communication data in massive legitimate network traffic, and mining structurally complex and latent relationships among flow-based network traffic to detect attacks has become the focus of many initiatives. Effectively analyzing massive network security data with high dimensions for suspicious flow diagnosis is a huge challenge. In addition, the uneven distribution of network traffic does not fully reflect the differences of class sample features, resulting in the low accuracy of attack detection. To solve these problems, a novel approach called the fuzzy entropy weighted natural nearest neighbor(FEW-NNN) method is proposed to enhance the accuracy and efficiency of flowbased network traffic attack detection. First, the FEW-NNN method uses the Fisher score and deep graph feature learning algorithm to remove unimportant features and reduce the data dimension. Then, according to the proposed natural nearest neighbor searching algorithm(NNN_Searching), the density of data points, each class center and the smallest enclosing sphere radius are determined correspondingly. Finally, a fuzzy entropy weighted KNN classification method based on affinity is proposed, which mainly includes the following three steps: 1、 the feature weights of samples are calculated based on fuzzy entropy values, 2、 the fuzzy memberships of samples are determined based on affinity among samples, and 3、 K-neighbors are selected according to the class-conditional weighted Euclidean distance, the fuzzy membership value of the testing sample is calculated based on the membership of k-neighbors, and then all testing samples are classified according to the fuzzy membership value of the samples belonging to each class;that is, the attack type is determined. The method has been applied to the problem of attack detection and validated based on the famous KDD99 and CICIDS-2017 datasets. From the experimental results shown in this paper, it is observed that the FEW-NNN method improves the accuracy and efficiency of flow-based network traffic attack detection. 展开更多
关键词 fuzzy entropy weighted KNN network attack detection fuzzy membership natural nearest neighbor network security intrusion detection system
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一种基于特征加权的K Nearest Neighbor算法 被引量:6
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作者 桑应宾 刘琼荪 《海南大学学报(自然科学版)》 CAS 2008年第4期352-355,共4页
传统的KNN算法一般采用欧式距离公式度量两样本间的距离.由于在实际样本数据集合中每一个属性对样本的贡献作用是不尽相同的,通常采用加权欧式距离公式.笔者提出一种计算权重的方法,即基于特征加权KNN算法.经实验证明,该算法与经典的赋... 传统的KNN算法一般采用欧式距离公式度量两样本间的距离.由于在实际样本数据集合中每一个属性对样本的贡献作用是不尽相同的,通常采用加权欧式距离公式.笔者提出一种计算权重的方法,即基于特征加权KNN算法.经实验证明,该算法与经典的赋权算法相比具有较好的分类效果. 展开更多
关键词 特征权重 K近邻 交叉验证
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The k Nearest Neighbors Estimator of the M-Regression in Functional Statistics 被引量:4
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作者 Ahmed Bachir Ibrahim Mufrah Almanjahie Mohammed Kadi Attouch 《Computers, Materials & Continua》 SCIE EI 2020年第12期2049-2064,共16页
It is well known that the nonparametric estimation of the regression function is highly sensitive to the presence of even a small proportion of outliers in the data.To solve the problem of typical observations when th... It is well known that the nonparametric estimation of the regression function is highly sensitive to the presence of even a small proportion of outliers in the data.To solve the problem of typical observations when the covariates of the nonparametric component are functional,the robust estimates for the regression parameter and regression operator are introduced.The main propose of the paper is to consider data-driven methods of selecting the number of neighbors in order to make the proposed processes fully automatic.We use thek Nearest Neighbors procedure(kNN)to construct the kernel estimator of the proposed robust model.Under some regularity conditions,we state consistency results for kNN functional estimators,which are uniform in the number of neighbors(UINN).Furthermore,a simulation study and an empirical application to a real data analysis of octane gasoline predictions are carried out to illustrate the higher predictive performances and the usefulness of the kNN approach. 展开更多
关键词 Functional data analysis quantile regression kNN method uniform nearest neighbor(UNN)consistency functional nonparametric statistics almost complete convergence rate
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Assessing the influence of the minimum measured diameter on forest spatial patterns and nearest neighborhood relationships 被引量:1
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作者 LI Yuan-fa YANG Hai-peng +2 位作者 WANG Hong-xiang YE Shao-ming LIU Wen-zhen 《Journal of Mountain Science》 SCIE CSCD 2019年第10期2308-2319,共12页
Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general c... Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general consensus on the height at which tree diameter should be measured[1.3 m:diameter at breast height(DBH)],the minimum measureddiameter(MMD)often varies in different studies.In this study,we assumed that the outcomes of forest structure analysis can be influenced by MMD and,to this end,we applied g(r)function and stand spatial structural parameters(SSSPs)to investigate how different MMDs affect forest spatial structure analysis in two pine-oak mixed forests(30 and 57 years old)in southwest China and one old-growth oak forest(>120years old)from northwest China.Our results showed that 1)MMD was closely related to the distribution patterns of forest trees.Tree distribution patterns at each observational scale(r=0-20 m)tended tobecome random as the MMD increased.The older the community,the earlier this random distribution pattern appeared.2)As the MMD increased,neighboring trees became more regularly distributed around a reference tree.In most cases,however,nearest neighbors of a reference tree were randomly distributed.3)Tree species mingling decreased with increasing diameter,but it decreased slowly in older forests.4)No correlations can be found between individual tree size differentiation and MMD.We recommend that comparisons of spatial structures between communities would be more effective if using a unified MMD criterion. 展开更多
关键词 Distribution patterns Minimum MEASURED DIAMETER Mixed FOREST nearest NEIGHBOR analysis Species MINGLING Uniform angle index
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Directional nearest neighbor query method for specified geographical direction space based on Voronoi diagram 被引量:2
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作者 李松 SONG Shuang +1 位作者 HAO Xiaohong ZHANG Liping 《High Technology Letters》 EI CAS 2022年第2期122-133,共12页
The existing nearest neighbor query methods cannot directly perform the nearest neighbor query of specified geographical direction space.In order to compensate the shortcomings of the existing methods,a directional ne... The existing nearest neighbor query methods cannot directly perform the nearest neighbor query of specified geographical direction space.In order to compensate the shortcomings of the existing methods,a directional nearest neighbor query method in specific direction space based on Voronoi diagram is put forward.This work studies two cases,i.e.the query point is static and the query point moves with a constant velocity.Under the static condition,the corresponding pruning method and the pruning algorithm of the specified direction nearest neighbor(pruning_SDNN algorithm)are proposed by combining the plane right-angle coordinate system with the north-west direction,and then according to the smallest external rectangle of Voronoi polygon,the specific query is made and the direction nearest neighbor query based on Voronoi rectangle(VR-DNN) algorithm is given.In the case of moving with a constant velocity,first of all,the combination of plane right angle coordinate system,geographical direction and circle are used,the query range is determined and pruning methods and the pruning algorithm of the direction nearest neighbor based on decision circle(pruning_DDNN algorithm) are put forward.Then,according to the different position of motion trajectory and Voronoi diagram,a specific query through the nature of Voronoi diagram is given.At last,the direction nearest neighbor query based on Voronoi diagram and motion trajectory(VM-DNN) algorithm is put forward.The theoretical research and experiments show that the proposed algorithm can effectively deal with the problem of the nearest neighbor query for a specified geographical direction space. 展开更多
关键词 nearest neighbor query direction Voronoi diagram rectangular plane coordinate system
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Nearest neighbor search algorithm based on multiple background grids for fluid simulation 被引量:1
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作者 郑德群 武频 +1 位作者 尚伟烈 曹啸鹏 《Journal of Shanghai University(English Edition)》 CAS 2011年第5期405-408,共4页
The core of smoothed particle hydrodynamics (SPH) is the nearest neighbor search subroutine. In this paper, a nearest neighbor search algorithm which is based on multiple background grids and support variable smooth... The core of smoothed particle hydrodynamics (SPH) is the nearest neighbor search subroutine. In this paper, a nearest neighbor search algorithm which is based on multiple background grids and support variable smooth length is introduced. Through tested on lid driven cavity flow, it is clear that this method can provide high accuracy. Analysis and experiments have been made on its parallelism, and the results show that this method has better parallelism and with adding processors its accuracy become higher, thus it achieves that efficiency grows in pace with accuracy. 展开更多
关键词 multiple background grids smoothed particle hydrodynamics (SPH) nearest neighbor search algorithm parallel computing
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Damage detection of 3D structures using nearest neighbor search method 被引量:1
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作者 Ali Abasi Vahid Harsij Ahmad Soraghi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第3期705-725,共21页
An innovative damage identification method using the nearest neighbor search method to assess 3D structures is presented.The frequency response function was employed as the input parameters to detect the severity and ... An innovative damage identification method using the nearest neighbor search method to assess 3D structures is presented.The frequency response function was employed as the input parameters to detect the severity and place of damage in 3D spaces since it includes the most dynamic characteristics of the structures.Two-dimensional principal component analysis was utilized to reduce the size of the frequency response function data.The nearest neighbor search method was employed to detect the severity and location of damage in different damage scenarios.The accuracy of the approach was verified using measured data from an experimental test;moreover,two asymmetric 3D numerical examples were considered as the numerical study.The superiority of the method was demonstrated through comparison with the results of damage identification by using artificial neural network.Different levels of white Gaussian noise were used for polluting the frequency response function data to investigate the robustness of the methods against noise-polluted data.The results indicate that both methods can efficiently detect the damage properties including its severity and location with high accuracy in the absence of noise,but the nearest neighbor search method is more robust against noisy data than the artificial neural network. 展开更多
关键词 damage identification damage index frequency response function two-dimensional principal component analysis nearest neighbor search artificial neural network white Gaussian noise
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Support Vector Machine-Based Fault Diagnosis of Power Transformer Using k Nearest-Neighbor Imputed DGA Dataset 被引量:3
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作者 Zahriah Binti Sahri Rubiyah Binti Yusof 《Journal of Computer and Communications》 2014年第9期22-31,共10页
Missing values are prevalent in real-world datasets and they may reduce predictive performance of a learning algorithm. Dissolved Gas Analysis (DGA), one of the most deployable methods for detecting and predicting inc... Missing values are prevalent in real-world datasets and they may reduce predictive performance of a learning algorithm. Dissolved Gas Analysis (DGA), one of the most deployable methods for detecting and predicting incipient faults in power transformers is one of the casualties. Thus, this paper proposes filling-in the missing values found in a DGA dataset using the k-nearest neighbor imputation method with two different distance metrics: Euclidean and Cityblock. Thereafter, using these imputed datasets as inputs, this study applies Support Vector Machine (SVM) to built models which are used to classify transformer faults. Experimental results are provided to show the effectiveness of the proposed approach. 展开更多
关键词 MISSING VALUES Dissolved Gas Analysis Support Vector Machine k-nearest NEIGHBORS
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Mapping aboveground biomass by integrating geospatial and forest inventory data through a k-nearest neighbor strategy in North Central Mexico 被引量:3
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作者 Carlos A AGUIRRE-SALADO Eduardo J TREVIO-GARZA +7 位作者 Oscar A AGUIRRE-CALDERóN Javier JIMNEZ-PREZ Marco A GONZLEZ-TAGLE José R VALDZ-LAZALDE Guillermo SNCHEZ-DíAZ Reija HAAPANEN Alejandro I AGUIRRE-SALADO Liliana MIRANDA-ARAGóN 《Journal of Arid Land》 SCIE CSCD 2014年第1期80-96,共17页
As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest research.Therefore,national governments are interested in developing forest-monitoring s... As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest research.Therefore,national governments are interested in developing forest-monitoring strategies using geospatial technology.Among statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(kNN).We compared four variations of distance metrics of the kNN for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical zone.Satellite derived,climatic,and topographic predictor variables were combined with the Mexican National Forest Inventory(NFI)data to accomplish the purpose.Performance of distance metrics applied into the kNN algorithm was evaluated using a cross validation leave-one-out technique.The results indicate that the Most Similar Neighbor(MSN)approach maximizes the correlation between predictor and response variables(r=0.9).Our results are in agreement with those reported in the literature.These findings confirm the predictive potential of the MSN approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+). 展开更多
关键词 k-nearest neighbor Mahalanobis most similar neighbor MODIS BRDF-adjusted reflectance forest inventory the policy of Reducing Emission from Deforestation and Forest Degradation
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Pruned fuzzy K-nearest neighbor classifier for beat classification 被引量:2
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作者 Muhammad Arif Muhammad Usman Akram Fayyaz-ul-Afsar Amir Minhas 《Journal of Biomedical Science and Engineering》 2010年第4期380-389,共10页
Arrhythmia beat classification is an active area of research in ECG based clinical decision support systems. In this paper, Pruned Fuzzy K-nearest neighbor (PFKNN) classifier is proposed to classify six types of beats... Arrhythmia beat classification is an active area of research in ECG based clinical decision support systems. In this paper, Pruned Fuzzy K-nearest neighbor (PFKNN) classifier is proposed to classify six types of beats present in the MIT-BIH Arrhythmia database. We have tested our classifier on ~ 103100 beats for six beat types present in the database. Fuzzy KNN (FKNN) can be implemented very easily but large number of training examples used for classification can be very time consuming and requires large storage space. Hence, we have proposed a time efficient Arif-Fayyaz pruning algorithm especially suitable for FKNN which can maintain good classification accuracy with appropriate retained ratio of training data. By using Arif-Fayyaz pruning algorithm with Fuzzy KNN, we have achieved a beat classification accuracy of 97% and geometric mean of sensitivity of 94.5% with only 19% of the total training examples. The accuracy and sensitivity is comparable to FKNN when all the training data is used. Principal Component Analysis is used to further reduce the dimension of feature space from eleven to six without compromising the accuracy and sensitivity. PFKNN was found to robust against noise present in the ECG data. 展开更多
关键词 ARRHYTHMIA ECG K-nearest NEIGHBOR PRUNING FUZZY Classification
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Entanglement and quantum phase transition in alternating XY spin chain with next-nearest neighbouring interactions 被引量:1
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作者 单传家 程维文 +2 位作者 刘堂昆 黄燕霞 李宏 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4002-4008,共7页
By using the method of density-matrix renormalization-group to solve the different spin spin correlation functions, the nearest-neighbouring entanglement (NNE) and the next-nearest-neighbouring entanglement (NNNE)... By using the method of density-matrix renormalization-group to solve the different spin spin correlation functions, the nearest-neighbouring entanglement (NNE) and the next-nearest-neighbouring entanglement (NNNE) of one-dimensional alternating Heisenberg XY spin chain are investigated in the presence of alternating the-nearestneighbouring interaction of exchange couplings, external magnetic fields and the next-nearest neighbouring interaction. For a dimerised ferromagnetic spin chain, the NNNE appears only above a critical dimerized interaction, meanwhile, the dimerized interaction a effects a quantum phase transition point and improves the NNNE to a large extent. We also study the effect of ferromagnetic or antiferromagnetic next-nearest neighbouring (NNN) interaction on the dynamics of NNE and NNNE. The ferromagnetic NNN interaction increases and shrinks the NNE below and above a critical frustrated interaction respectively, while the antiferromagnetic NNN interaction always reduces the NNE. The antiferromagnetic NNN interaction results in a large value of NNNE compared with the case where the NNN interaction is ferromagnetic. 展开更多
关键词 the entanglement alternating XY spin chain the next-nearest neighbouring interactions
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A Short-Term Traffic Flow Forecasting Method Based on a Three-Layer K-Nearest Neighbor Non-Parametric Regression Algorithm 被引量:7
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作者 Xiyu Pang Cheng Wang Guolin Huang 《Journal of Transportation Technologies》 2016年第4期200-206,共7页
Short-term traffic flow is one of the core technologies to realize traffic flow guidance. In this article, in view of the characteristics that the traffic flow changes repeatedly, a short-term traffic flow forecasting... Short-term traffic flow is one of the core technologies to realize traffic flow guidance. In this article, in view of the characteristics that the traffic flow changes repeatedly, a short-term traffic flow forecasting method based on a three-layer K-nearest neighbor non-parametric regression algorithm is proposed. Specifically, two screening layers based on shape similarity were introduced in K-nearest neighbor non-parametric regression method, and the forecasting results were output using the weighted averaging on the reciprocal values of the shape similarity distances and the most-similar-point distance adjustment method. According to the experimental results, the proposed algorithm has improved the predictive ability of the traditional K-nearest neighbor non-parametric regression method, and greatly enhanced the accuracy and real-time performance of short-term traffic flow forecasting. 展开更多
关键词 Three-Layer Traffic Flow Forecasting K-nearest Neighbor Non-Parametric Regression
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Basic Tenets of Classification Algorithms K-Nearest-Neighbor, Support Vector Machine, Random Forest and Neural Network: A Review 被引量:1
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作者 Ernest Yeboah Boateng Joseph Otoo Daniel A. Abaye 《Journal of Data Analysis and Information Processing》 2020年第4期341-357,共17页
In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (... In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (RF) and Neural Network (NN) as the main statistical tools were reviewed. The aim was to examine and compare these nonparametric classification methods on the following attributes: robustness to training data, sensitivity to changes, data fitting, stability, ability to handle large data sizes, sensitivity to noise, time invested in parameter tuning, and accuracy. The performances, strengths and shortcomings of each of the algorithms were examined, and finally, a conclusion was arrived at on which one has higher performance. It was evident from the literature reviewed that RF is too sensitive to small changes in the training dataset and is occasionally unstable and tends to overfit in the model. KNN is easy to implement and understand but has a major drawback of becoming significantly slow as the size of the data in use grows, while the ideal value of K for the KNN classifier is difficult to set. SVM and RF are insensitive to noise or overtraining, which shows their ability in dealing with unbalanced data. Larger input datasets will lengthen classification times for NN and KNN more than for SVM and RF. Among these nonparametric classification methods, NN has the potential to become a more widely used classification algorithm, but because of their time-consuming parameter tuning procedure, high level of complexity in computational processing, the numerous types of NN architectures to choose from and the high number of algorithms used for training, most researchers recommend SVM and RF as easier and wieldy used methods which repeatedly achieve results with high accuracies and are often faster to implement. 展开更多
关键词 Classification Algorithms NON-PARAMETRIC K-nearest-Neighbor Neural Networks Random Forest Support Vector Machines
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Approximate aggregate nearest neighbor search on moving objects trajectories
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作者 Mohammad Reza Abbasifard Hassan Naderi +1 位作者 Zohreh Fallahnejad Omid Isfahani Alamdari 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第11期4246-4253,共8页
Aggregate nearest neighbor(ANN) search retrieves for two spatial datasets T and Q, segment(s) of one or more trajectories from the set T having minimum aggregate distance to points in Q. When interacting with large am... Aggregate nearest neighbor(ANN) search retrieves for two spatial datasets T and Q, segment(s) of one or more trajectories from the set T having minimum aggregate distance to points in Q. When interacting with large amounts of trajectories, this process would be very time-consuming due to consecutive page loads. An approximate method for finding segments with minimum aggregate distance is proposed which can improve the response time. In order to index large volumes of trajectories, scalable and efficient trajectory index(SETI) structure is used. But some refinements are provided to temporal index of SETI to improve the performance of proposed method. The experiments were performed with different number of query points and percentages of dataset. It is shown that proposed method besides having an acceptable precision, can reduce the computation time significantly. It is also shown that the main fraction of search time among load time, ANN and computing convex and centroid, is related to ANN. 展开更多
关键词 APPROXIMATE AGGREGATE k nearest neighbor(AAk NN) s
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