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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:13
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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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Pruned fuzzy K-nearest neighbor classifier for beat classification 被引量:4
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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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GNN-CRC: Discriminative Collaborative Representation-Based Classification via Gabor Wavelet Transformation and Nearest Neighbor
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作者 ZHANG Yanghao ZENG Shaoning +1 位作者 ZENG Wei GOU Jianping 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第5期657-665,共9页
Collaborative representation-based classification(CRC) is a distance based method, and it obtains the original contributions from all samples to solve the sparse representation coefficient. We find out that it helps t... Collaborative representation-based classification(CRC) is a distance based method, and it obtains the original contributions from all samples to solve the sparse representation coefficient. We find out that it helps to enhance the discrimination in classification by integrating other distance based features and/or adding signal preprocessing to the original samples. In this paper, we propose an improved version of the CRC method which uses the Gabor wavelet transformation to preprocess the samples and also adapts the nearest neighbor(NN)features, and hence we call it GNN-CRC. Firstly, Gabor wavelet transformation is applied to minimize the effects from the background in face images and build Gabor features into the input data. Secondly, the distances solved by NN and CRC are fused together to obtain a more discriminative classification. Extensive experiments are conducted to evaluate the proposed method for face recognition with different instantiations. The experimental results illustrate that our method outperforms the naive CRC as well as some other state-of-the-art algorithms. 展开更多
关键词 face recognition COLLABORATIVE REPRESENTATION GABOR wavelet transformation nearest neighbor (NN) image classification
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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. On... 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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An Enhanced Integrated Method for Healthcare Data Classification with Incompleteness
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作者 Sonia Goel Meena Tushir +4 位作者 Jyoti Arora Tripti Sharma Deepali Gupta Ali Nauman Ghulam Muhammad 《Computers, Materials & Continua》 SCIE EI 2024年第11期3125-3145,共21页
In numerous real-world healthcare applications,handling incomplete medical data poses significant challenges for missing value imputation and subsequent clustering or classification tasks.Traditional approaches often ... In numerous real-world healthcare applications,handling incomplete medical data poses significant challenges for missing value imputation and subsequent clustering or classification tasks.Traditional approaches often rely on statistical methods for imputation,which may yield suboptimal results and be computationally intensive.This paper aims to integrate imputation and clustering techniques to enhance the classification of incomplete medical data with improved accuracy.Conventional classification methods are ill-suited for incomplete medical data.To enhance efficiency without compromising accuracy,this paper introduces a novel approach that combines imputation and clustering for the classification of incomplete data.Initially,the linear interpolation imputation method alongside an iterative Fuzzy c-means clustering method is applied and followed by a classification algorithm.The effectiveness of the proposed approach is evaluated using multiple performance metrics,including accuracy,precision,specificity,and sensitivity.The encouraging results demonstrate that our proposed method surpasses classical approaches across various performance criteria. 展开更多
关键词 Incomplete data nearest neighbor linear interpolation IMPUTATION CLUSTERING classification
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A Representation-Based Pseudo Nearest Neighbor Classifier
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作者 Yanwei Qi 《国际计算机前沿大会会议论文集》 2018年第1期13-13,共1页
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基于MEC-SOR模型的茶旅消费触发研究
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作者 陈蔚 李群 王英 《佳木斯大学学报(自然科学版)》 2025年第7期148-151,共4页
本研究基于MEC-SOR(Means-End Chain-Stimulus-Organism-Response)模型,探讨茶旅消费的触发机制。通过设计多维度测量题项(自我形象、愉悦兴趣、茶生活方式),结合探索性因子分析与验证性因子分析,构建茶旅消费的结构模型。研究采用K近邻... 本研究基于MEC-SOR(Means-End Chain-Stimulus-Organism-Response)模型,探讨茶旅消费的触发机制。通过设计多维度测量题项(自我形象、愉悦兴趣、茶生活方式),结合探索性因子分析与验证性因子分析,构建茶旅消费的结构模型。研究采用K近邻(KNN)分类模型对632份样本数据进行分析,结果显示,茶生活方式维度的因子载荷(均值0.837)与方差解释率(32.33%)最高,是消费的主要驱动因素;模型测试集准确率达92.11%,AUC值为0.89,验证了模型的有效性。特征重要性分析表明,茶生活方式的体验价值评分与社交影响对消费触发作用显著,为茶旅产品优化提供了理论支持。 展开更多
关键词 MEC-SOR模型 茶旅消费 触发机制 因子分析 K近邻分类
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基于GGO-KD-KNN算法的下肢步态识别研究
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作者 李传江 丁新豪 +2 位作者 涂嘉俊 李昂 尹仕熠 《上海师范大学学报(自然科学版中英文)》 2025年第2期141-145,共5页
为了提高下肢步态识别的准确性和效率,针对K最近邻(KNN)算法参数调节困难的问题,提出了一种基于灰雁优化-K维树-K最近邻(GGO-KD-KNN)算法的下肢步态识别方法.首先,利用表面肌电信号(sEMG)采集下肢肌肉活动信息,并将信号划分为5个步态阶... 为了提高下肢步态识别的准确性和效率,针对K最近邻(KNN)算法参数调节困难的问题,提出了一种基于灰雁优化-K维树-K最近邻(GGO-KD-KNN)算法的下肢步态识别方法.首先,利用表面肌电信号(sEMG)采集下肢肌肉活动信息,并将信号划分为5个步态阶段.然后,进行sEMG去噪,并提取时域和频域特征.接着,用GGO算法基于灰雁群体行为进行启发式优化,优化KNN算法的K值和距离度量,并通过适应度迭代寻找最优解.实验结果表明,通过GGO算法优化的步态识别精度达到了98.23%,标准差为0.264,相较于其他常用算法,基于GGO-KD-KNN算法的步态识别方法展现出更高的分类准确率和稳定性,为下肢智能辅助装置的研究和开发提供了有力的理论支持. 展开更多
关键词 下肢步态识别 表面肌电信号(sEMG) 灰雁优化-K维树-K最近邻(GGO-KD-KNN)算法 分类优化
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一种基于KNN和随机仿射的边界样本合成过采样方法 被引量:1
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作者 冷强奎 孙薛梓 孟祥福 《智能系统学报》 北大核心 2025年第2期329-343,共15页
过采样是处理不平衡数据分类问题的有效策略。本文提出了一种基于K近邻(K-nearest neighbor,KNN)和随机仿射的边界样本合成过采样方法,用于改进现有过采样方法的种子样本选择阶段和合成样本生成阶段。首先,引入三近邻理论,建立样本间有... 过采样是处理不平衡数据分类问题的有效策略。本文提出了一种基于K近邻(K-nearest neighbor,KNN)和随机仿射的边界样本合成过采样方法,用于改进现有过采样方法的种子样本选择阶段和合成样本生成阶段。首先,引入三近邻理论,建立样本间有效的内在近邻关系,并去除数据集中的噪声,以降低后续分类器的过拟合风险。其次,准确识别那些难以学习且包含丰富信息的少数类边界样本,并将其用作采样种子。最后,利用局部随机仿射代替线性插值机制,在原始数据的近似流形中均匀地生成合成样本。相比于传统过采样方法,本文方法能更充分挖掘数据集中的重要边界信息,从而为分类器提供更多辅助以改善其分类性能。在18个基准数据集上,与8种经典采样方法(结合4种不同分类器)进行了大量对比实验。结果表明,本文所提方法获得了更高的F1分数和几何均值(G-mean),可以更为有效地解决不平衡数据分类问题。此外,统计分析也证实该方法具有更高的弗里德曼排名(Friedman ranking)。 展开更多
关键词 K近邻 线性插值 边界样本 自然分布 过采样 三近邻理论 随机仿射变换 不平衡分类
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基于医疗大数据结合人工智能算法在呼吸机故障识别与预防性维护中的应用 被引量:4
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作者 宫昕晨 温林 《中国医疗设备》 2025年第3期41-48,共8页
目的提出一种基于粒子群优化(Particle Swarm Optimization,PSO)算法和反向传播(Back Propagation,BP)神经网络模型的呼吸机故障识别与预防性维护策略,旨在提高呼吸机设备管理、维修水平,为呼吸机预防性维护提供参考。方法选取2017—202... 目的提出一种基于粒子群优化(Particle Swarm Optimization,PSO)算法和反向传播(Back Propagation,BP)神经网络模型的呼吸机故障识别与预防性维护策略,旨在提高呼吸机设备管理、维修水平,为呼吸机预防性维护提供参考。方法选取2017—2023年我院使用的呼吸机日常质量控制数据、临床使用数据、环境数据等多模态数据为研究对象,介绍PSO算法,建立粒子群优化-反向传播(PSO-BP)模型,同时引入K近邻(K-Nearest Neighbor Classification,KNN)模型、支持向量机(Support Vector Machine,SVM)模型以及极端梯度提升(eXtreme Gradient Boosting,XGBoost)模型作为对比模型,并选择准确度(Accuracy,ACC)、精准度(Precision,PRE)、召回率、F1得分以及曲线下面积(Area Under Curve,AUC)对模型进行评价。结果训练后的PSO-BP模型ACC、PRE、召回率、F1得分及AUC值分别为90.05%、91.00%、89.30%、0.90以及0.88;相对于KNN、SVM、XGBoost以及BP模型,PSO-BP模型识别ACC分别提高了6.64%、4.50%、3.32%、7.35%;召回率、F1得分及AUC值在一定程度上也得到了提高。模型最优阈值为0.6768,呼吸机安全区、稳定区、危险区以及高危区区间分别为[0,0.3384]、(0.3384,0.6768]、(0.6768,0.8384]、(0.8384,1.0000]。结论通过高通量医疗大数据建立的PSO-BP模型可有效识别呼吸机故障,并可使用定量数据为呼吸机预防性维护提供参考,具有一定的理论和实际应用意义。 展开更多
关键词 PSO-BP模型 故障识别 预防性维护 K近邻模型 支持向量机 极端梯度提升 高通量数据
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基于多流形的单样本人脸模糊分类算法
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作者 徐洁 杨长茂 +1 位作者 陈建平 王文琰 《计算机工程与设计》 北大核心 2025年第3期719-725,共7页
为解决单个人脸样本分类中样本数量不足的问题,提出一种多流形模糊分类算法(FMMC)。通过分割图像增加“样本”数量,构造类别子流形。引入模糊集理论,定义类别流形隶属度,弱化不同类别子流形上语义相同的图块相似度,强化同一类别子流形... 为解决单个人脸样本分类中样本数量不足的问题,提出一种多流形模糊分类算法(FMMC)。通过分割图像增加“样本”数量,构造类别子流形。引入模糊集理论,定义类别流形隶属度,弱化不同类别子流形上语义相同的图块相似度,强化同一类别子流形上不同位置图块的类别信息相关性,有效限制离群图块对分类结果的影响,提高分类的性能。在3个公开人脸数据库上进行实验,其结果表明,FMMC对单个样本问题的分类可行且有效。 展开更多
关键词 单样本 K最近邻分类器 模糊集 多流形 切割 流形隶属度 分类
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面向卷绕机装配车间的无线信号聚类分层定位方法
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作者 丁司懿 童辉辉 +1 位作者 毛新华 张洁 《纺织学报》 北大核心 2025年第6期212-222,共11页
为解决卷绕机装配车间这种复杂环境中难以高效准确定位的问题,提出了基于无线网络(WiFi)的分层定位方法。通过分析装配车间无线网络环境的特点及其特定的定位需求,并结合卷绕机装配车间内的无线网络定位的特点,开发了一种结合XGBoost分... 为解决卷绕机装配车间这种复杂环境中难以高效准确定位的问题,提出了基于无线网络(WiFi)的分层定位方法。通过分析装配车间无线网络环境的特点及其特定的定位需求,并结合卷绕机装配车间内的无线网络定位的特点,开发了一种结合XGBoost分类模型算法、K-means聚类算法和加权K最近邻(WKNN)算法的无线网络分层定位方法。同时,依据装配车间的特点与需求对定位区域进行有效划分并初步构建指纹库,根据装配车间内WiFi信号的特点,使用K-means聚类算法分割并更新指纹库;然后利用XGBoost分类模型算法确定子区域实现粗定位,再用WKNN算法精确定位。实验结果表明:该方法在定位精度上比传统WKNN算法提高了143.82%,平均定位时间减少了约20%;这些改进有效提升了卷绕机装配车间中无线网络定位的准确性和效率。 展开更多
关键词 卷绕机装配车间 无线网络 分层定位方法 XGBoost分类模型 K-MEANS聚类算法 加权K最近邻算法
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基于E-KNN算法的企业数据分级分类管理方法研究
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作者 吕晓英 《贵阳学院学报(自然科学版)》 2025年第1期70-74,共5页
针对现阶段企业数据管理方法存在的准确率低下与分级分类管理难题,采用指数函数距离加权与因子分析方法对K最近邻算法进行了改进,提出了一种新型的企业数据分级分类管理方法。实验结果表明,通过加入10-折交叉验证与网格搜索,K最近邻算... 针对现阶段企业数据管理方法存在的准确率低下与分级分类管理难题,采用指数函数距离加权与因子分析方法对K最近邻算法进行了改进,提出了一种新型的企业数据分级分类管理方法。实验结果表明,通过加入10-折交叉验证与网格搜索,K最近邻算法在训练集和测试集的自动分级分类精确度分别能够达到85.9%与85.3%。进一步通过指数函数距离加权与因子分析方法进行改进,K最近邻算法在训练集和测试集的分级分类预测准确率更是分别达到了95.1%与95.4%。由此可知,所提出的改进方法能够显著提高企业数据管理的效率和精度,对于推动企业数据治理向更高水平发展具有重要意义。 展开更多
关键词 K最近邻算法 因子分析法 企业数据 分级分类 管理
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基于K最近邻算法的网络舆情信息自动摘要方法
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作者 侯国辉 《计算机应用文摘》 2025年第12期174-176,共3页
针对现有摘要生成方法难以准确捕捉网络舆情关键信息的问题,文章提出一种基于K最近邻算法的网络舆情信息自动摘要方法,首先通过文本向量化将舆情信息转化为计算机可识别的文本向量,然后计算文本间的夹角余弦值以确定内容相似度。基于相... 针对现有摘要生成方法难以准确捕捉网络舆情关键信息的问题,文章提出一种基于K最近邻算法的网络舆情信息自动摘要方法,首先通过文本向量化将舆情信息转化为计算机可识别的文本向量,然后计算文本间的夹角余弦值以确定内容相似度。基于相似度计算结果,采用K最近邻算法选取K个最相似的已知类别文本,并根据其标签确定文本类别。最后,从各类别中提取最具代表性的关键信息,整合生成连贯的摘要文本。实验结果表明,该方法能有效处理海量网络舆情信息,显著提升了信息处理的效率和准确性。 展开更多
关键词 K最近邻算法 网络舆情 自动摘要 特征向量 样本分类
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基于数据包络分析的互联网医院智慧分级诊疗服务系统
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作者 邹双忆 《自动化技术与应用》 2025年第5期173-177,共5页
为了缓解医疗资源紧张的问题,研究设计面向互联网医院的分级诊疗服务系统。首先采用数据包络分析来对互联网医院的医疗资源配置情况进行分析,再设计面向诊疗服务系统的集成分类模型,该集成分类模型涉及三种基分类器。最后在区块链技术... 为了缓解医疗资源紧张的问题,研究设计面向互联网医院的分级诊疗服务系统。首先采用数据包络分析来对互联网医院的医疗资源配置情况进行分析,再设计面向诊疗服务系统的集成分类模型,该集成分类模型涉及三种基分类器。最后在区块链技术的支持下设计了医疗联盟体系和分级诊疗服务系统。结果显示,集成分类模型在训练集和测试集上的准确率最大值分别为70.89%和70.04%,所设计系统转诊模块的响应时间和中央处理器占用率的最大值分别为147 ms和16.7%,具有良好的性能,为缓解医疗资源紧张提供技术支持。 展开更多
关键词 数据包络分析 分级诊疗 KNN SVM CART决策树
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Classification Fusion in Wireless Sensor Networks 被引量:3
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作者 LIU Chun-Ting HUO Hong +2 位作者 FANG Tao LI De-Ren SHEN Xiao 《自动化学报》 EI CSCD 北大核心 2006年第6期947-955,共9页
In wireless sensor networks, target classification differs from that in centralized sensing systems because of the distributed detection, wireless communication and limited resources. We study the classification probl... In wireless sensor networks, target classification differs from that in centralized sensing systems because of the distributed detection, wireless communication and limited resources. We study the classification problem of moving vehicles in wireless sensor networks using acoustic signals emitted from vehicles. Three algorithms including wavelet decomposition, weighted k-nearest-neighbor and Dempster-Shafer theory are combined in this paper. Finally, we use real world experimental data to validate the classification methods. The result shows that wavelet based feature extraction method can extract stable features from acoustic signals. By fusion with Dempster's rule, the classification performance is improved. 展开更多
关键词 Wireless sensor networks classification fusion wavelet decomposition weighted k-nearest-neighbor Dempster-Shafer theory
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Multi-Level Max-Margin Analysis for Semantic Classification of Satellite Images
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作者 HU Fan XIA Gui-Song SUN Hong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第1期47-54,共8页
The performance of scene classification of satellite images strongly relies on the discriminative power of the low-level and mid-level feature representation. This paper presents a novel approach, named multi-level ma... The performance of scene classification of satellite images strongly relies on the discriminative power of the low-level and mid-level feature representation. This paper presents a novel approach, named multi-level max-margin analysis (M 3 DA) for semantic classification for high-resolution satellite images. In our M 3 DA model, the maximum entropy discrimination latent Dirichlet allocation (MedLDA) model is applied to learn the topic-level features first, and then based on a bag-of-words repre- sentation of low-level local image features, the large margin nearest neighbor (LMNN) classifier is used to optimize a multiple soft label composed of word-level features (generated by SVM classifier) and topic-level features. The categorization performances on 21-class land-use dataset have demonstrated that the proposed model in multi-level max-margin scheme can distinguish different categories of land-use scenes reasonably. 展开更多
关键词 satellite image classification topic model maximum entropy discrimination latent Dirichlet allocation large margin nearest neighbor classifier multi-level max-margin
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基于组合加权k近邻分类的无线传感网络节点复制攻击检测方法 被引量:7
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作者 赵晓峰 王平水 《传感技术学报》 CAS CSCD 北大核心 2024年第6期1056-1060,共5页
无线传感网络节点体积小,隐蔽性强,节点复制攻击检测的难度较大,为此提出一种基于组合加权k近邻分类的无线传感网络节点复制攻击检测方法。通过信标节点的空间位置数据与相距跳数得出各节点之间的相似程度,结合高斯径向基核函数求解未... 无线传感网络节点体积小,隐蔽性强,节点复制攻击检测的难度较大,为此提出一种基于组合加权k近邻分类的无线传感网络节点复制攻击检测方法。通过信标节点的空间位置数据与相距跳数得出各节点之间的相似程度,结合高斯径向基核函数求解未知节点的横轴、纵轴的空间坐标,确定各网络节点的空间位置;根据网络节点的属性特征与投票机制建立节点复制攻击模型,凭借组合加权k近邻分类法划分节点类型,并将结果传送至簇头节点,由簇头节点做出最后的仲裁,识别出节点复制攻击行为。仿真结果表明,所提方法的节点复制攻击检测率最大值为99.5%,最小值为97.9%,对节点复制攻击检测的耗时为5.41 s,通信开销数据包数量最大值为209个,最小值为81个。 展开更多
关键词 无线传感网络 攻击检测 组合加权k近邻分类 复制节点 部署区域 信标节点
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Shape classification based on singular value decomposition transform
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作者 SHAABAN Zyad ARIF Thawar BABA Sami KREKOR Lala 《重庆邮电大学学报(自然科学版)》 北大核心 2009年第2期246-252,共7页
In this paper, a new shape classification system based on singular value decomposition (SVD) transform using nearest neighbour classifier was proposed. The gray scale image of the shape object was converted into a bla... In this paper, a new shape classification system based on singular value decomposition (SVD) transform using nearest neighbour classifier was proposed. The gray scale image of the shape object was converted into a black and white image. The squared Euclidean distance transform on binary image was applied to extract the boundary image of the shape. SVD transform features were extracted from the the boundary of the object shapes. In this paper, the proposed classification system based on SVD transform feature extraction method was compared with classifier based on moment invariants using nearest neighbour classifier. The experimental results showed the advantage of our proposed classification system. 展开更多
关键词 奇异值分解 形状分类 分解变换 分类系统 欧氏距离变换 特征提取 黑白图像 近邻分类
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一种基于半监督的句子情感分类模型 被引量:1
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作者 苏静 Murtadha Ahmed 《重庆大学学报》 CAS CSCD 北大核心 2024年第12期100-113,共14页
句子情感分类致力于挖掘文本中的情感语义,以基于BERT(bidirectional encoder representations from transformers)的深度网络模型表现最佳。这类模型的性能极度依赖大量高质量标注数据,而现实中标注样本往往比较稀缺,导致深度神经网络(... 句子情感分类致力于挖掘文本中的情感语义,以基于BERT(bidirectional encoder representations from transformers)的深度网络模型表现最佳。这类模型的性能极度依赖大量高质量标注数据,而现实中标注样本往往比较稀缺,导致深度神经网络(deep neural network,DNN)容易在小规模样本集上过拟合,难以准确捕捉句子的隐含情感特征。尽管现有的半监督模型有效利用了未标注样本特征,但对引入未标注样本可能导致错误逐渐累积问题没有有效处理。半监督模型在对测试数据集进行预测后不会重新评估和修正上次的标注结果,无法充分挖掘测试数据的特征信息。研究提出一种新型的半监督句子情感分类模型。该模型首先提出基于K-近邻算法的权重机制,为置信度高的样本分配较高权重,尽可能减少错误信息在模型训练中的传播。接着,采用两阶段训练策略,使模型能对测试数据中预测错误的样本进行及时修正,通过多个数据集的测试,证明本模型在小规模样本集上也能获得良好性能。 展开更多
关键词 句子情感分类 半监督学习 K-近邻 TRANSFORMER
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