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GHM-FKNN:a generalized Heronian mean based fuzzy k-nearest neighbor classifier for the stock trend prediction
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作者 吴振峰 WANG Mengmeng +1 位作者 LAN Tian ZHANG Anyuan 《High Technology Letters》 EI CAS 2023年第2期122-129,共8页
Stock trend prediction is a challenging problem because it involves many variables.Aiming at the problem that some existing machine learning techniques, such as random forest(RF), probabilistic random forest(PRF), k-n... Stock trend prediction is a challenging problem because it involves many variables.Aiming at the problem that some existing machine learning techniques, such as random forest(RF), probabilistic random forest(PRF), k-nearest neighbor(KNN), and fuzzy KNN(FKNN), have difficulty in accurately predicting the stock trend(uptrend or downtrend) for a given date, a generalized Heronian mean(GHM) based FKNN predictor named GHM-FKNN was proposed.GHM-FKNN combines GHM aggregation function with the ideas of the classical FKNN approach.After evaluation, the comparison results elucidated that GHM-FKNN outperformed the other best existing methods RF, PRF, KNN and FKNN on independent test datasets corresponding to three stocks, namely AAPL, AMZN and NFLX.Compared with RF, PRF, KNN and FKNN, GHM-FKNN achieved the best performance with accuracy of 62.37% for AAPL, 58.25% for AMZN, and 64.10% for NFLX. 展开更多
关键词 stock trend prediction Heronian mean fuzzy k-nearest neighbor(FKNN)
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Enhancing Cancer Classification through a Hybrid Bio-Inspired Evolutionary Algorithm for Biomarker Gene Selection 被引量:1
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作者 Hala AlShamlan Halah AlMazrua 《Computers, Materials & Continua》 SCIE EI 2024年第4期675-694,共20页
In this study,our aim is to address the problem of gene selection by proposing a hybrid bio-inspired evolutionary algorithm that combines Grey Wolf Optimization(GWO)with Harris Hawks Optimization(HHO)for feature selec... In this study,our aim is to address the problem of gene selection by proposing a hybrid bio-inspired evolutionary algorithm that combines Grey Wolf Optimization(GWO)with Harris Hawks Optimization(HHO)for feature selection.Themotivation for utilizingGWOandHHOstems fromtheir bio-inspired nature and their demonstrated success in optimization problems.We aimto leverage the strengths of these algorithms to enhance the effectiveness of feature selection in microarray-based cancer classification.We selected leave-one-out cross-validation(LOOCV)to evaluate the performance of both two widely used classifiers,k-nearest neighbors(KNN)and support vector machine(SVM),on high-dimensional cancer microarray data.The proposed method is extensively tested on six publicly available cancer microarray datasets,and a comprehensive comparison with recently published methods is conducted.Our hybrid algorithm demonstrates its effectiveness in improving classification performance,Surpassing alternative approaches in terms of precision.The outcomes confirm the capability of our method to substantially improve both the precision and efficiency of cancer classification,thereby advancing the development ofmore efficient treatment strategies.The proposed hybridmethod offers a promising solution to the gene selection problem in microarray-based cancer classification.It improves the accuracy and efficiency of cancer diagnosis and treatment,and its superior performance compared to other methods highlights its potential applicability in realworld cancer classification tasks.By harnessing the complementary search mechanisms of GWO and HHO,we leverage their bio-inspired behavior to identify informative genes relevant to cancer diagnosis and treatment. 展开更多
关键词 Bio-inspired algorithms BIOINFORMATICS cancer classification evolutionary algorithm feature selection gene expression grey wolf optimizer harris hawks optimization k-nearest neighbor support vector machine
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Real-Time Spreading Thickness Monitoring of High-core Rockfill Dam Based on K-nearest Neighbor Algorithm 被引量:4
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作者 Denghua Zhong Rongxiang Du +2 位作者 Bo Cui Binping Wu Tao Guan 《Transactions of Tianjin University》 EI CAS 2018年第3期282-289,共8页
During the storehouse surface rolling construction of a core rockfilldam, the spreading thickness of dam face is an important factor that affects the construction quality of the dam storehouse' rolling surface and... During the storehouse surface rolling construction of a core rockfilldam, the spreading thickness of dam face is an important factor that affects the construction quality of the dam storehouse' rolling surface and the overallquality of the entire dam. Currently, the method used to monitor and controlspreading thickness during the dam construction process is artificialsampling check after spreading, which makes it difficult to monitor the entire dam storehouse surface. In this paper, we present an in-depth study based on real-time monitoring and controltheory of storehouse surface rolling construction and obtain the rolling compaction thickness by analyzing the construction track of the rolling machine. Comparatively, the traditionalmethod can only analyze the rolling thickness of the dam storehouse surface after it has been compacted and cannot determine the thickness of the dam storehouse surface in realtime. To solve these problems, our system monitors the construction progress of the leveling machine and employs a real-time spreading thickness monitoring modelbased on the K-nearest neighbor algorithm. Taking the LHK core rockfilldam in Southwest China as an example, we performed real-time monitoring for the spreading thickness and conducted real-time interactive queries regarding the spreading thickness. This approach provides a new method for controlling the spreading thickness of the core rockfilldam storehouse surface. 展开更多
关键词 Core rockfill dam Dam storehouse surface construction Spreading thickness k-nearest neighbor algorithm Real-time monitor
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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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A Study of EM Algorithm as an Imputation Method: A Model-Based Simulation Study with Application to a Synthetic Compositional Data
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作者 Yisa Adeniyi Abolade Yichuan Zhao 《Open Journal of Modelling and Simulation》 2024年第2期33-42,共10页
Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear mode... Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear model is the most used technique for identifying hidden relationships between underlying random variables of interest. However, data quality is a significant challenge in machine learning, especially when missing data is present. The linear regression model is a commonly used statistical modeling technique used in various applications to find relationships between variables of interest. When estimating linear regression parameters which are useful for things like future prediction and partial effects analysis of independent variables, maximum likelihood estimation (MLE) is the method of choice. However, many datasets contain missing observations, which can lead to costly and time-consuming data recovery. To address this issue, the expectation-maximization (EM) algorithm has been suggested as a solution for situations including missing data. The EM algorithm repeatedly finds the best estimates of parameters in statistical models that depend on variables or data that have not been observed. This is called maximum likelihood or maximum a posteriori (MAP). Using the present estimate as input, the expectation (E) step constructs a log-likelihood function. Finding the parameters that maximize the anticipated log-likelihood, as determined in the E step, is the job of the maximization (M) phase. This study looked at how well the EM algorithm worked on a made-up compositional dataset with missing observations. It used both the robust least square version and ordinary least square regression techniques. The efficacy of the EM algorithm was compared with two alternative imputation techniques, k-Nearest Neighbor (k-NN) and mean imputation (), in terms of Aitchison distances and covariance. 展开更多
关键词 Compositional Data Linear Regression Model Least Square Method Robust Least Square Method Synthetic Data Aitchison Distance Maximum Likelihood Estimation Expectation-Maximization algorithm k-nearest neighbor and Mean imputation
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Wireless Communication Signal Strength Prediction Method Based on the K-nearest Neighbor Algorithm
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作者 Zhao Chen Ning Xiong +6 位作者 Yujue Wang Yong Ding Hengkui Xiang Chenjun Tang Lingang Liu Xiuqing Zou Decun Luo 《国际计算机前沿大会会议论文集》 2019年第1期238-240,共3页
Existing interference protection systems lack automatic evaluation methods to provide scientific, objective and accurate assessment results. To address this issue, this paper develops a layout scheme by geometrically ... Existing interference protection systems lack automatic evaluation methods to provide scientific, objective and accurate assessment results. To address this issue, this paper develops a layout scheme by geometrically modeling the actual scene, so that the hand-held full-band spectrum analyzer would be able to collect signal field strength values for indoor complex scenes. An improved prediction algorithm based on the K-nearest neighbor non-parametric kernel regression was proposed to predict the signal field strengths for the whole plane before and after being shield. Then the highest accuracy set of data could be picked out by comparison. The experimental results show that the improved prediction algorithm based on the K-nearest neighbor non-parametric kernel regression can scientifically and objectively predict the indoor complex scenes’ signal strength and evaluate the interference protection with high accuracy. 展开更多
关键词 INTERFERENCE protection k-nearest neighbor algorithm NON-PARAMETRIC KERNEL regression SIGNAL field STRENGTH
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A KNN-based two-step fuzzy clustering weighted algorithm for WLAN indoor positioning 被引量:3
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作者 Xu Yubin Sun Yongliang Ma Lin 《High Technology Letters》 EI CAS 2011年第3期223-229,共7页
Although k-nearest neighbors (KNN) is a popular fingerprint match algorithm for its simplicity and accuracy, because it is sensitive to the circumstances, a fuzzy c-means (FCM) clustering algorithm is applied to i... Although k-nearest neighbors (KNN) is a popular fingerprint match algorithm for its simplicity and accuracy, because it is sensitive to the circumstances, a fuzzy c-means (FCM) clustering algorithm is applied to improve it. Thus, a KNN-based two-step FCM weighted (KTFW) algorithm for indoor positioning in wireless local area networks (WLAN) is presented in this paper. In KTFW algorithm, k reference points (RPs) chosen by KNN are clustered through FCM based on received signal strength (RSS) and location coordinates. The right clusters are chosen according to rules, so three sets of RPs are formed including the set of k RPs chosen by KNN and are given different weights. RPs supposed to have better contribution to positioning accuracy are given larger weights to improve the positioning accuracy. Simulation results indicate that KTFW generally outperforms KNN and its complexity is greatly reduced through providing initial clustering centers for FCM. 展开更多
关键词 wireless local area networks (WLAN) indoor positioning k-nearest neighbors (KNN) fuzzy c-means (FCM) clustering center
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FUZZY WITHIN-CLASS MATRIX PRINCIPAL COMPONENT ANALYSIS AND ITS APPLICATION TO FACE RECOGNITION 被引量:3
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作者 朱玉莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期141-147,共7页
Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of sampl... Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of samples. As a result, the extracted features cannot provide enough useful information for distinguishing pat- tern from one another, and further resulting in degradation of classification performance. To fullly use class in- formation of samples, a novel method, called the fuzzy within-class MatPCA (F-WMatPCA)is proposed. F-WMatPCA utilizes the fuzzy K-nearest neighbor method(FKNN) to fuzzify the class membership degrees of a training sample and then performs fuzzy MatPCA within these patterns having the same class label. Due to more class information is used in feature extraction, F-WMatPCA can intuitively improve the classification perfor- mance. Experimental results in face databases and some benchmark datasets show that F-WMatPCA is effective and competitive than MatPCA. The experimental analysis on face image databases indicates that F-WMatPCA im- proves the recognition accuracy and is more stable and robust in performing classification than the existing method of fuzzy-based F-Fisherfaces. 展开更多
关键词 face recognition principal component analysis (PCA) matrix pattern PCA(MatPCA) fuzzy k-nearest neighbor(FKNN) fuzzy within-class MatPCA(F-WMatPCA)
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Rapid prediction of flow and concentration fields in solid-liquid suspensions of slurry electrolysis tanks
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作者 Tingting Lu Kang Li +4 位作者 Hongliang Zhao Wei Wang Zhenhao Zhou Xiaoyi Cai Fengqin Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2006-2016,共11页
Slurry electrolysis(SE),as a hydrometallurgical process,has the characteristic of a multitank series connection,which leads to various stirring conditions and a complex solid suspension state.The computational fluid d... Slurry electrolysis(SE),as a hydrometallurgical process,has the characteristic of a multitank series connection,which leads to various stirring conditions and a complex solid suspension state.The computational fluid dynamics(CFD),which requires high computing resources,and a combination with machine learning was proposed to construct a rapid prediction model for the liquid flow and solid concentration fields in a SE tank.Through scientific selection of calculation samples via orthogonal experiments,a comprehensive dataset covering a wide range of conditions was established while effectively reducing the number of simulations and providing reasonable weights for each factor.Then,a prediction model of the SE tank was constructed using the K-nearest neighbor algorithm.The results show that with the increase in levels of orthogonal experiments,the prediction accuracy of the model improved remarkably.The model established with four factors and nine levels can accurately predict the flow and concentration fields,and the regression coefficients of average velocity and solid concentration were 0.926 and 0.937,respectively.Compared with traditional CFD,the response time of field information prediction in this model was reduced from 75 h to 20 s,which solves the problem of serious lag in CFD applied alone to actual production and meets real-time production control requirements. 展开更多
关键词 slurry electrolysis solid-liquid suspension computational fluid dynamics k-nearest neighbor algorithm rapid prediction
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基于自适应近邻信息的模糊C均值聚类算法
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作者 高云龙 李建鹏 +3 位作者 郑兴莘 邵桂芳 祝青园 曹超 《光学精密工程》 EI CAS CSCD 北大核心 2024年第7期1045-1058,共14页
传统的模糊C均值算法直接基于原始数据进行聚类,数据的内在结构可能会被噪声、异常值或其他因素破坏,因此聚类性能会受到影响。为提升FCM算法的鲁棒性,提出了一种基于自适应近邻信息的模糊C均值聚类算法。近邻信息指的是一种基于数据点... 传统的模糊C均值算法直接基于原始数据进行聚类,数据的内在结构可能会被噪声、异常值或其他因素破坏,因此聚类性能会受到影响。为提升FCM算法的鲁棒性,提出了一种基于自适应近邻信息的模糊C均值聚类算法。近邻信息指的是一种基于数据点之间相似度的度量,每个数据点都可以看作其他数据点的近邻,但是不同数据点之间的相似度是不同的。将样本点的近邻信息GX和类中心点的近邻信息GV融入基础FCM模型中,为聚类过程提供更多的数据结构信息,用于指导聚类算法中的簇划分过程,以提升算法的稳定性,并提出了3个迭代算法求解本文提出的聚类模型。与其他先进聚类算法对比,在部分基准数据集上聚类性能有10%以上的提升,同时还从参数敏感性、收敛性、消融实验等方面对算法进行评价。实验结果可以充分显示本文提出的聚类算法的可行性与有效性。 展开更多
关键词 模糊C均值聚类 自适应近邻 算法鲁棒性 迭代算法
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基于优化模糊C-means算法的不平衡大数据分类研究
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作者 卓柳俊 曾心怡 《信息技术》 2024年第10期14-21,29,共9页
针对不平衡大数据的分类问题,提出一种优化模糊C-means算法的不平衡大数据分类算法。先计算C-means模糊交叉算子,定义优化函数,并求解大数据不平衡增益。利用Spark分类平台,确定大数据样本压缩模糊近邻值的取值范围,再通过放大近邻值的... 针对不平衡大数据的分类问题,提出一种优化模糊C-means算法的不平衡大数据分类算法。先计算C-means模糊交叉算子,定义优化函数,并求解大数据不平衡增益。利用Spark分类平台,确定大数据样本压缩模糊近邻值的取值范围,再通过放大近邻值的处理方式,定义不平衡阈向量,从而完善整个分类流程,完成基于优化模糊C-means算法的不平衡大数据分类方法的设计。实验结果表明,上述分类方法的应用,可将正例信息、负例信息的取样长度区间完全分离开来,能有效解决因不平衡大数据分类不精准造成的信息样本混淆的问题,符合实际应用需求。 展开更多
关键词 优化模糊C-means算法 不平衡大数据 交叉算子 卡方检验 压缩模糊近邻值
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A Memetic Algorithm With Competition for the Capacitated Green Vehicle Routing Problem 被引量:8
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作者 Ling Wang Jiawen Lu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期516-526,共11页
In this paper, a memetic algorithm with competition(MAC) is proposed to solve the capacitated green vehicle routing problem(CGVRP). Firstly, the permutation array called traveling salesman problem(TSP) route is used t... In this paper, a memetic algorithm with competition(MAC) is proposed to solve the capacitated green vehicle routing problem(CGVRP). Firstly, the permutation array called traveling salesman problem(TSP) route is used to encode the solution, and an effective decoding method to construct the CGVRP route is presented accordingly. Secondly, the k-nearest neighbor(k NN) based initialization is presented to take use of the location information of the customers. Thirdly, according to the characteristics of the CGVRP, the search operators in the variable neighborhood search(VNS) framework and the simulated annealing(SA) strategy are executed on the TSP route for all solutions. Moreover, the customer adjustment operator and the alternative fuel station(AFS) adjustment operator on the CGVRP route are executed for the elite solutions after competition. In addition, the crossover operator is employed to share information among different solutions. The effect of parameter setting is investigated using the Taguchi method of design-ofexperiment to suggest suitable values. Via numerical tests, it demonstrates the effectiveness of both the competitive search and the decoding method. Moreover, extensive comparative results show that the proposed algorithm is more effective and efficient than the existing methods in solving the CGVRP. 展开更多
关键词 Capacitated green VEHICLE ROUTING problem(CGVRP) COMPETITION k-nearest neighbor(kNN) local INTENSIFICATION memetic algorithm
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Metabonomic analysis of hepatitis B virus-induced liver failure:identification of potential diagnostic biomarkers by fuzzy support vector machine 被引量:11
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作者 Yong MAO Xin HUANG +3 位作者 Ke YU Hai-bin QU Chang-xiao LIU Yi-yu CHENG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第6期474-481,共8页
Hepatitis B virus (HBV)-induced liver failure is an emergent liver disease leading to high mortality. The severity of liver failure may be reflected by the profile of some metabolites. This study assessed the potent... Hepatitis B virus (HBV)-induced liver failure is an emergent liver disease leading to high mortality. The severity of liver failure may be reflected by the profile of some metabolites. This study assessed the potential of using metabolites as biomarkers for liver failure by identifying metabolites with good discriminative performance for its phenotype. The serum samples from 24 HBV-indueed liver failure patients and 23 healthy volunteers were collected and analyzed by gas chromatography-mass spectrometry (GC-MS) to generate metabolite profiles. The 24 patients were further grouped into two classes according to the severity of liver failure. Twenty-five eommensal peaks in all metabolite profiles were extracted, and the relative area values of these peaks were used as features for each sample. Three algorithms, F-test, k-nearest neighbor (KNN) and fuzzy support vector machine (FSVM) combined with exhaustive search (ES), were employed to identify a subset of metabolites (biomarkers) that best predict liver failure. Based on the achieved experimental dataset, 93.62% predictive accuracy by 6 features was selected with FSVM-ES and three key metabolites, glyeerie acid, cis-aeonitie acid and citric acid, are identified as potential diagnostic biomarkers. 展开更多
关键词 Metabolite profile analysis Potential diagnostic biomarker identification k-nearest neighbor (KNN) fuzzy supportvector machine (FSVM) Exhaustive search (ES) Gas chromatography-mass spectrometry (GC-MS) Hepatitis B virus (HBV)-induced liver failure
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An Improved Whale Optimization Algorithm for Feature Selection 被引量:4
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作者 Wenyan Guo Ting Liu +1 位作者 Fang Dai Peng Xu 《Computers, Materials & Continua》 SCIE EI 2020年第1期337-354,共18页
Whale optimization algorithm(WOA)is a new population-based meta-heuristic algorithm.WOA uses shrinking encircling mechanism,spiral rise,and random learning strategies to update whale’s positions.WOA has merit in term... Whale optimization algorithm(WOA)is a new population-based meta-heuristic algorithm.WOA uses shrinking encircling mechanism,spiral rise,and random learning strategies to update whale’s positions.WOA has merit in terms of simple calculation and high computational accuracy,but its convergence speed is slow and it is easy to fall into the local optimal solution.In order to overcome the shortcomings,this paper integrates adaptive neighborhood and hybrid mutation strategies into whale optimization algorithms,designs the average distance from itself to other whales as an adaptive neighborhood radius,and chooses to learn from the optimal solution in the neighborhood instead of random learning strategies.The hybrid mutation strategy is used to enhance the ability of algorithm to jump out of the local optimal solution.A new whale optimization algorithm(HMNWOA)is proposed.The proposed algorithm inherits the global search capability of the original algorithm,enhances the exploitation ability,improves the quality of the population,and thus improves the convergence speed of the algorithm.A feature selection algorithm based on binary HMNWOA is proposed.Twelve standard datasets from UCI repository test the validity of the proposed algorithm for feature selection.The experimental results show that HMNWOA is very competitive compared to the other six popular feature selection methods in improving the classification accuracy and reducing the number of features,and ensures that HMNWOA has strong search ability in the search feature space. 展开更多
关键词 Whale optimization algorithm Filter and Wrapper model k-nearest neighbor method Adaptive neighborhood hybrid mutation
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Research on Initialization on EM Algorithm Based on Gaussian Mixture Model 被引量:4
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作者 Ye Li Yiyan Chen 《Journal of Applied Mathematics and Physics》 2018年第1期11-17,共7页
The EM algorithm is a very popular maximum likelihood estimation method, the iterative algorithm for solving the maximum likelihood estimator when the observation data is the incomplete data, but also is very effectiv... The EM algorithm is a very popular maximum likelihood estimation method, the iterative algorithm for solving the maximum likelihood estimator when the observation data is the incomplete data, but also is very effective algorithm to estimate the finite mixture model parameters. However, EM algorithm can not guarantee to find the global optimal solution, and often easy to fall into local optimal solution, so it is sensitive to the determination of initial value to iteration. Traditional EM algorithm select the initial value at random, we propose an improved method of selection of initial value. First, we use the k-nearest-neighbor method to delete outliers. Second, use the k-means to initialize the EM algorithm. Compare this method with the original random initial value method, numerical experiments show that the parameter estimation effect of the initialization of the EM algorithm is significantly better than the effect of the original EM algorithm. 展开更多
关键词 EM algorithm GAUSSIAN MIXTURE Model k-nearest neighbor K-MEANS algorithm INITIALIZATION
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模糊线性判别QR分析的茶叶近红外光谱鉴别分析
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作者 胡彩平 何成遇 +4 位作者 孔丽微 朱优优 武斌 周浩祥 孙俊 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2023年第12期3802-3805,共4页
不同品种茶叶因其所含的有机化学成分不同,其效果也会有差别。所以,寻找出一种能准确迅速的鉴别茶叶品种的技术方法是非常重要的。近红外光谱(NIR)分析是一种无损检测技术,能很好的鉴别茶叶品种。使用NIR光谱仪采集茶叶的NIR数据。为了... 不同品种茶叶因其所含的有机化学成分不同,其效果也会有差别。所以,寻找出一种能准确迅速的鉴别茶叶品种的技术方法是非常重要的。近红外光谱(NIR)分析是一种无损检测技术,能很好的鉴别茶叶品种。使用NIR光谱仪采集茶叶的NIR数据。为了对包含噪声信号的茶叶近红外光谱进行准确鉴别,提出了一种模糊线性判别QR分析的新方法,可以对茶叶近红外光谱进行准确分类。通过使用模糊线性判别分析(FLDA)将由主成分分析(PCA)压缩的茶叶近红外光谱数据进行降维,由模糊线性判别分析得出的特征向量构建鉴别向量矩阵,对鉴别向量矩阵进行矩阵的QR分解,得到新的鉴别向量矩阵。经过模糊线性判别QR分析后使用K近邻算法进行分类,具有准确率高等优点。以岳西翠兰、六安瓜片、施集毛峰和黄山毛峰四种茶叶为研究样本,每类65个,茶叶样本总数为260个。采集茶叶近红外光谱数据的仪器为AntarisⅡ型傅里叶近红外光谱仪对光谱数据进行预处理,采用多元散射校正,由于采集到的茶叶光谱数据存在散射干扰。以此得到的近红外光谱数据的维数为1557维,通过主成分分析压缩数据集的维数,使得光谱数据集的维数达到7维。经压缩过后的光谱数据集中的鉴别信息再通过模糊线性判别QR分析进行提取,使得光谱数据的维数降低到3维。利用K近邻算法对茶叶样本进行分类,实现对茶叶品种的准确分类。最后进行三种算法分析结果的比较,分别是主成分分析结合K近邻算法、主成分分析和线性判别分析结合K近邻算法、主成分分析和模糊线性判别QR分析结合K近邻算法。在权重指数m=2,K=1条件下,最后的分类准确率分别为83.89%, 87.78%和98.33%。实验结果显示:模糊线性判别QR分析可以实现茶叶近红外光谱的准确鉴别分析,其展现出来的效果比主成分分析和线性判别分析表现的效果更好。 展开更多
关键词 模糊线性判别分析 主成分分析 近红外光谱 K近邻算法
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基于集成精细复合多元多尺度模糊熵的齿轮箱故障诊断 被引量:1
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作者 杨小强 宫建成 +1 位作者 安立周 刘晓明 《机电工程》 CAS 北大核心 2023年第3期335-343,共9页
针对齿轮箱故障信号具有非线性和非平稳性的特点,且目前的方法对其特征提取不够充分这一问题,对不同形式粗粒化方法的集成、多通道信号处理方法在模糊熵算法上的应用进行了研究,提出了一种新的特征提取方法,即集成精细复合多元多尺度模... 针对齿轮箱故障信号具有非线性和非平稳性的特点,且目前的方法对其特征提取不够充分这一问题,对不同形式粗粒化方法的集成、多通道信号处理方法在模糊熵算法上的应用进行了研究,提出了一种新的特征提取方法,即集成精细复合多元多尺度模糊熵(ERCmvMFE)算法,在此基础上,结合t分布随机邻域嵌入(t-SNE)和人工鱼群算法优化的核极限学习机(AFSA-KELM),提出了一种新的齿轮箱故障综合诊断方法。首先,采用多种形式粗粒化方法的集成方法以及多通道信号处理方法,对模糊熵算法进行了改进,并进行了齿轮箱故障的初始特征提取;然后,通过t-SNE压缩原始故障特征,实现了维数的约简,并将低维故障特征输入至AFSA-KELM中进行了故障的分类识别;最后,为了对ERCmvMFE方法的特征提取性能进行测试,采用QPZZ-II旋转机械故障模拟测试平台进行了相关的实验。实验结果表明:采用新的齿轮箱故障综合诊断方法能够对不同类型的齿轮箱故障进行可靠诊断,对齿轮箱5种工况下的20次识别实验中,获得的平均准确率可达98.92%,标准差为0.956,识别准确率和稳定性均优于其他对比方法。研究结果表明:采用ERCmvMFE算法能够更充分地提取出齿轮箱的故障特征,因此,基于该特征提取方法的故障诊断方法具有更高的齿轮箱故障识别准确率。 展开更多
关键词 集成精细复合多元多尺度模糊熵 人工鱼群算法优化的核极限学习机 t分布随机邻域嵌入 特征提取 多粗粒化处理 多通道信号处理 故障分类识别
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基于fNIRS的恐惧情绪分级研究
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作者 许博俊 刘化东 李梦琪 《现代电子技术》 2023年第20期142-146,共5页
功能性近红外光谱技术(fNIRS)能够实现对恐惧情绪的分级。文中设计情绪诱发范式,并对恐惧程度进行分级,将恐惧水平分为三级(无恐惧、弱恐惧和强恐惧)。其次,采集20位受试者在三种情绪诱发视频下的fNIRS实验数据,采用支持向量机(SVM)、K... 功能性近红外光谱技术(fNIRS)能够实现对恐惧情绪的分级。文中设计情绪诱发范式,并对恐惧程度进行分级,将恐惧水平分为三级(无恐惧、弱恐惧和强恐惧)。其次,采集20位受试者在三种情绪诱发视频下的fNIRS实验数据,采用支持向量机(SVM)、K近邻算法(KNN)和随机森林(RF)等三种算法作为分类器,提取fNIRS领域常用统计学特征和熵特征进行比较研究。结果表明,常用统计学特征最高准确率达到84%,而通过集合经验模态分解(EEMD)分解的模糊熵(FuEn)特征最终获得的准确率高达93.98%。研究结果表明,通过EEMD分解的FuEn是一种相较于常用统计学特征更加优秀的恐惧情绪分级特征,可为后续其他情绪的分级奠定基础。 展开更多
关键词 功能性近红外光谱技术 恐惧情绪 情绪诱发 模糊熵 集合经验模态分解 支持向量机 随机森林 K近邻算法
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基于Relax散射点特征提取的舰船目标识别方法 被引量:7
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作者 王锦章 魏存伟 +3 位作者 刘先康 梁菁 任杰 孙菲 《电子科技》 2011年第4期8-11,共4页
针对基于高分辨距离像(HRRP)的舰船目标识别问题,提出了一种基于Relax散射点特征提取和设计了基于散射中心最近邻模糊分类器的目标识别方法。首先对数据进行预处理,然后基于Relax算法提取出散射中心,最后通过最近邻模糊分类器进行识别... 针对基于高分辨距离像(HRRP)的舰船目标识别问题,提出了一种基于Relax散射点特征提取和设计了基于散射中心最近邻模糊分类器的目标识别方法。首先对数据进行预处理,然后基于Relax算法提取出散射中心,最后通过最近邻模糊分类器进行识别匹配。通过仿真4类军民船目标的数据进行测试,验证结果表明该方法在舰船目标识别领域具有很好的应用前景。 展开更多
关键词 高分辨距离像 RELAX算法 最近邻模糊分类器
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近邻样本密度和隶属度加权FCM算法的遥感图像分类方法 被引量:12
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作者 刘小芳 何彬彬 《仪器仪表学报》 EI CAS CSCD 北大核心 2011年第10期2242-2247,共6页
针对FCM算法具有对数据集进行等划分趋势的缺陷,利用样本本身的近邻分布特性,提出近邻样本密度加权FCM(NSD-WFCM)、近邻样本隶属度加权FCM(NSM-WFCM)以及近邻样本密度和隶属度加权FCM(NSDM-WFCM)算法,并应用于遥感图像分类。对比FCM算法... 针对FCM算法具有对数据集进行等划分趋势的缺陷,利用样本本身的近邻分布特性,提出近邻样本密度加权FCM(NSD-WFCM)、近邻样本隶属度加权FCM(NSM-WFCM)以及近邻样本密度和隶属度加权FCM(NSDM-WFCM)算法,并应用于遥感图像分类。对比FCM算法,NSD-WFCM、NSM-WFCM和NSDM-WFCM算法的总体分类精度和Kappa系数分别提高了5.67%、7.50%和11.17%;8.50%、11.25%和16.75%。实验结果表明:这些加权方法都在一定程度上克服了FCM算法的缺陷,提高了遥感图像的无监督分类能力,其中,NSM-WFCM算法的分类性能优于NSD-WFCM算法的分类性能,NSDM-WFCM算法分类性能最好。 展开更多
关键词 遥感图像分类 FCM算法 加权FCM算法 近邻样本密度 近邻样本隶属度
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