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Enhancing Cancer Classification through a Hybrid Bio-Inspired Evolutionary Algorithm for Biomarker Gene Selection
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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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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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基于PCA+KNN和kernal-PCA+KNN算法的废旧纺织物鉴别
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作者 李宁宁 刘正东 +2 位作者 王海滨 韩熹 李文霞 《分析测试学报》 CAS CSCD 北大核心 2024年第7期1039-1045,共7页
该研究采集了15类废旧纺织物的4 998张近红外谱图,以7∶3的比例分为训练集和验证集,并分别采用主成分分析(PCA)与核主成分分析(kernal-PCA)两种不同降维方法对数据进行降维,并选用余弦相似度(cosine)核作为kernal-PCA的最佳核函数,最后... 该研究采集了15类废旧纺织物的4 998张近红外谱图,以7∶3的比例分为训练集和验证集,并分别采用主成分分析(PCA)与核主成分分析(kernal-PCA)两种不同降维方法对数据进行降维,并选用余弦相似度(cosine)核作为kernal-PCA的最佳核函数,最后分别将PCA和kernal-PCA降维处理后的数据进行k-近邻算法(KNN)训练。结果表明,kernal-PCA+KNN的模型准确率(95.17%)优于PCA+KNN模型的准确率(92.34%)。研究表明,kernal-PCA+KNN算法可以实现15类废旧纺织物识别准确率的提升,为废旧纺织物在线近红外自动分拣提供有力的技术支撑。 展开更多
关键词 废旧纺织物 主成分分析(PCA) 核主成分分析(kernel-PCA) k-近邻算法(KNN) 分类识别
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一种基于卷积神经网络的室内定位方法
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作者 张丽 董建 +1 位作者 孙长智 刘成刚 《黑龙江工业学院学报(综合版)》 2024年第5期80-87,共8页
针对实际室内定位场景中的无线接入点信号不稳定引起定位精度低的问题,提出一种基于卷积神经网络的室内定位方法,该方法包括离线阶段和在线阶段,其中离线阶段主要完成对无线接入点信号采集,经过预处理后作为卷积神经网络模型的训练数据... 针对实际室内定位场景中的无线接入点信号不稳定引起定位精度低的问题,提出一种基于卷积神经网络的室内定位方法,该方法包括离线阶段和在线阶段,其中离线阶段主要完成对无线接入点信号采集,经过预处理后作为卷积神经网络模型的训练数据。在线阶段利用训练好的模型完成粗定位,估计位置所在的区域,最后利用加权k近邻算法计算精确的位置坐标。通过与SVR、KNN算法对比,结果表明,在二维平面回归定位问题中优于其他算法。 展开更多
关键词 卷积神经网络 室内定位 加权k近邻算法 位置指纹算法
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城市轨道交通超短时客流预测模型研究及应用
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作者 费佳莹 严俊钦 陈佳 《交通与运输》 2024年第1期47-52,共6页
超短时客流预测是城市轨道交通调度指挥中的关键基础性问题,现有的方法及模型各有优缺点,尚不能很好地满足现场实际工作需要。首先,基于上海城市轨道交通海量客流数据,对客流特征及其影响因素进行提取与分析,在此基础上引入“K最近邻算... 超短时客流预测是城市轨道交通调度指挥中的关键基础性问题,现有的方法及模型各有优缺点,尚不能很好地满足现场实际工作需要。首先,基于上海城市轨道交通海量客流数据,对客流特征及其影响因素进行提取与分析,在此基础上引入“K最近邻算法”研究建立超短时客流预测模型。以上海城市轨道交通网络为实际背景的初步应用及结果分析表明,研究成果能对运营当天早晚高峰时段(7:00—10:00和17:00—20:00)客流做出超短时预测,具有较好的准确性、时效性和实用性,为调度指挥提供有力的客流数据支撑,助力构建城市轨道交通网络智慧客运组织调度系统。 展开更多
关键词 城市轨道交通 超短时客流预测 K最近邻算法 历史特征日 相似参照日
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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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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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Condition Monitoring of Roller Bearing by K-star Classifier andK-nearest Neighborhood Classifier Using Sound Signal
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作者 Rahul Kumar Sharma V.Sugumaran +1 位作者 Hemantha Kumar M.Amarnath 《Structural Durability & Health Monitoring》 EI 2017年第1期1-17,共17页
Most of the machineries in small or large-scale industry have rotating elementsupported by bearings for rigid support and accurate movement. For proper functioning ofmachinery, condition monitoring of the bearing is v... Most of the machineries in small or large-scale industry have rotating elementsupported by bearings for rigid support and accurate movement. For proper functioning ofmachinery, condition monitoring of the bearing is very important. In present study soundsignal is used to continuously monitor bearing health as sound signals of rotatingmachineries carry dynamic information of components. There are numerous studies inliterature that are reporting superiority of vibration signal of bearing fault diagnosis.However, there are very few studies done using sound signal. The cost associated withcondition monitoring using sound signal (Microphone) is less than the cost of transducerused to acquire vibration signal (Accelerometer). This paper employs sound signal forcondition monitoring of roller bearing by K-star classifier and k-nearest neighborhoodclassifier. The statistical feature extraction is performed from acquired sound signals. Thentwo-layer feature selection is done using J48 decision tree algorithm and random treealgorithm. These selected features were classified using K-star classifier and k-nearestneighborhood classifier and parametric optimization is performed to achieve the maximumclassification accuracy. The classification results for both K-star classifier and k-nearestneighborhood classifier for condition monitoring of roller bearing using sound signals werecompared. 展开更多
关键词 K-star k-nearest neighborhood K-NN machine learning approach conditionmonitoring fault diagnosis roller bearing decision tree algorithm J-48 random treealgorithm decision making two-layer feature selection sound signal statistical features
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Effective and Efficient Video Compression by the Deep Learning Techniques
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作者 Karthick Panneerselvam K.Mahesh +1 位作者 V.L.Helen Josephine A.Ranjith Kumar 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1047-1061,共15页
Deep learning has reached many successes in Video Processing.Video has become a growing important part of our daily digital interactions.The advancement of better resolution content and the large volume offers serious... Deep learning has reached many successes in Video Processing.Video has become a growing important part of our daily digital interactions.The advancement of better resolution content and the large volume offers serious challenges to the goal of receiving,distributing,compressing and revealing highquality video content.In this paper we propose a novel Effective and Efficient video compression by the Deep Learning framework based on the flask,which creatively combines the Deep Learning Techniques on Convolutional Neural Networks(CNN)and Generative Adversarial Networks(GAN).The video compression method involves the layers are divided into different groups for data processing,using CNN to remove the duplicate frames,repeating the single image instead of the duplicate images by recognizing and detecting minute changes using GAN and recorded with Long Short-Term Memory(LSTM).Instead of the complete image,the small changes generated using GAN are substituted,which helps with frame-level compression.Pixel wise comparison is performed using K-nearest Neighbours(KNN)over the frame,clustered with K-means and Singular Value Decomposition(SVD)is applied for every frame in the video for all three colour channels[Red,Green,Blue]to decrease the dimension of the utility matrix[R,G,B]by extracting its latent factors.Video frames are packed with parameters with the aid of a codec and converted to video format and the results are compared with the original video.Repeated experiments on several videos with different sizes,duration,Frames per second(FPS),and quality results demonstrated a significant resampling rate.On normal,the outcome delivered had around a 10%deviation in quality and over half in size when contrasted,and the original video. 展开更多
关键词 Convolutional neural networks(CNN) generative adversarial network(GAN) singular value decomposition(SVD) k-nearest neighbours(KNN) stochastic gradient descent(SGD) long short-term memory(LSTM)
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Optimal integration of solar home systems and appliance scheduling for residential homes under severe national load shedding
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作者 Sakhile Twala Xianming Ye +1 位作者 Xiaohua Xia Lijun Zhang 《Journal of Automation and Intelligence》 2023年第4期227-238,共12页
In developing countries like South Africa,users experienced more than 1030 hours of load shedding outages in just the first half of 2023 due to inadequate power supply from the national grid.Residential homes that can... In developing countries like South Africa,users experienced more than 1030 hours of load shedding outages in just the first half of 2023 due to inadequate power supply from the national grid.Residential homes that cannot afford to take actions to mitigate the challenges of load shedding are severely inconvenienced as they have to reschedule their demand involuntarily.This study presents optimal strategies to guide households in determining suitable scheduling and sizing solutions for solar home systems to mitigate the inconvenience experienced by residents due to load shedding.To start with,we predict the load shedding stages that are used as input for the optimal strategies by using the K-Nearest Neighbour(KNN)algorithm.Based on an accurate forecast of the future load shedding patterns,we formulate the residents’inconvenience and the loss of power supply probability during load shedding as the objective function.When solving the multi-objective optimisation problem,four different strategies to fight against load shedding are identified,namely(1)optimal home appliance scheduling(HAS)under load shedding;(2)optimal HAS supported by solar panels;(3)optimal HAS supported by batteries,and(4)optimal HAS supported by the solar home system with both solar panels and batteries.Among these strategies,appliance scheduling with an optimally sized 9.6 kWh battery and a 2.74 kWp panel array of five 550 Wp panels,eliminates the loss of power supply probability and reduces the inconvenience by 92%when tested under the South African load shedding cases in 2023. 展开更多
关键词 Load shedding Inconvenience Optimal scheduling and sizing strategies k-nearest neighbour(KNN) Multi-objective mixed integer nonlinear optimisation
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一种基于近邻搜索的快速k-近邻分类算法 被引量:16
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作者 王壮 胡卫东 +1 位作者 郁文贤 庄钊文 《系统工程与电子技术》 EI CSCD 北大核心 2002年第4期100-102,共3页
针对传统快速k 近邻分类算法的缺陷 ,提出了一种基于近邻搜索的快速k 近邻分类算法———超球搜索法。该方法通过对特征空间的预组织 ,使分类在以待分样本为中心的超球内进行 ,有效地缩小了搜索范围。实验结果表明 ,在相同识别率和k值... 针对传统快速k 近邻分类算法的缺陷 ,提出了一种基于近邻搜索的快速k 近邻分类算法———超球搜索法。该方法通过对特征空间的预组织 ,使分类在以待分样本为中心的超球内进行 ,有效地缩小了搜索范围。实验结果表明 ,在相同识别率和k值的情况下 ,超球搜索法的识别速度优于基本k 近邻法和传统快速k 近邻算法———及时终止法 。 展开更多
关键词 近邻搜索 快速κ-近邻分类算法 超球搜索法
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一种基于信息增益的K-NN改进算法 被引量:9
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作者 魏孝章 豆增发 《计算机工程与应用》 CSCD 北大核心 2007年第19期188-191,共4页
针对传统K-NN算法易受单个属性干扰和时间效率较低的问题,提出了利用信息增益和可拓关联度对其进行改进。通过计算属性的信息增益来确定属性的权重系数,根据权重系数将属性划分为关键属性、次要属性和无关属性,在计算欧氏距离时引入权... 针对传统K-NN算法易受单个属性干扰和时间效率较低的问题,提出了利用信息增益和可拓关联度对其进行改进。通过计算属性的信息增益来确定属性的权重系数,根据权重系数将属性划分为关键属性、次要属性和无关属性,在计算欧氏距离时引入权重系数,使各个属性的作用受其重要性的约束,有效地提高了K-NN算法的抗干扰能力和精确性。将属性空间划分为若干个子空间,利用可拓关联度将待测样本映射到某个子空间中,由这个子空间组成搜索空间,减少计算量,提高时间效率;测试结果表明,改进后的算法可行有效。 展开更多
关键词 K—NN算法 信息增益 信息熵 可拓关联度
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一种基于信息增益的K-NN改进算法 被引量:5
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作者 豆增发 王英强 王保保 《电子科技》 2006年第12期52-56,共5页
K-最近邻(K-nearestneighbor,简称KNN)算法是一种在人工智能领域如专家系统、数据挖掘、模式识别等方面广泛应用的算法。该算法简单有效,易于实现,但是其K值难以确定,而且分类结果易受单个属性干扰。文中提出了一种简单易行的K值确定方... K-最近邻(K-nearestneighbor,简称KNN)算法是一种在人工智能领域如专家系统、数据挖掘、模式识别等方面广泛应用的算法。该算法简单有效,易于实现,但是其K值难以确定,而且分类结果易受单个属性干扰。文中提出了一种简单易行的K值确定方法,并利用Quinlan信息增益理论,提出了基于信息增益的K-最近邻改进算法。通过实验证明,改进后的K-NN算法具有较强的抗干扰能力和较好的精确性。 展开更多
关键词 K-最近邻算法 信息增益 信息熵
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一种混合局部搜索算法的遗传算法求解旅行商问题 被引量:8
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作者 宗德才 王康康 《计算机应用与软件》 CSCD 2015年第3期266-270,305,共6页
针对遗传算法容易产生早熟现象以及局部寻优能力较差的缺点,提出一种求解旅行商问题的高效混合遗传算法。该算法首先用加权最近邻法产生初始种群,对种群中相同的个体,用K-近邻法产生新的个体代替相同的个体,然后淘汰适应性较差的个体,... 针对遗传算法容易产生早熟现象以及局部寻优能力较差的缺点,提出一种求解旅行商问题的高效混合遗传算法。该算法首先用加权最近邻法产生初始种群,对种群中相同的个体,用K-近邻法产生新的个体代替相同的个体,然后淘汰适应性较差的个体,用交叉操作产生新的个体,最后,对部分个体进行3-opt优化变异,对种群中优秀个体用改进的Lin-Kernighan算法进行优化。对TSPLIB中部分实例的仿真结果表明,所提出的混合局部搜索算法的改进遗传算法在求解TSP问题时可以高效地获得高质量的解。 展开更多
关键词 遗传算法 加权最近邻法 K-近邻法 Lin-Kernighan算法 3-opt算法 旅行商问题
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基于多种机器学习方法填补大豆基因组缺失的比较研究 被引量:2
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作者 于合龙 刘雨帆 +1 位作者 张继成 唐友 《大豆科学》 CAS CSCD 北大核心 2021年第1期122-129,共8页
为探索大豆基因组测序不同程度缺失数据的有效填补措施,提升数据分析综合能力,本研究以大豆株高与叶面积两组性状的基因组基因型数据为研究对象,进行5%、10%和20%不同缺失比例的人为数据缺失处理,分别运用K近邻算法、SoftImpute算法和... 为探索大豆基因组测序不同程度缺失数据的有效填补措施,提升数据分析综合能力,本研究以大豆株高与叶面积两组性状的基因组基因型数据为研究对象,进行5%、10%和20%不同缺失比例的人为数据缺失处理,分别运用K近邻算法、SoftImpute算法和随机森林算法3种机器学习方法对缺失数据进行填补,分析填补数据的准确性和性能。对原始数据和填补后的数据进行全基因组关联分析,分别对比填补后的数据和原始数据的分析效果。从准确率来看,随机森林算法填补的准确率最高;从运行时间上来看,SoftImpute算法的运行速度最快;运行内存方面,SoftImpute算法的运行内存最小,而当数据量达到10 000×1 000时,K近邻填补算法的运行内存最小。在不考虑运行时间和运行内存的因素,且对填补的准确率要求较高的情况下,随机森林算法的填补效果要优于K近邻填补算法和SoftImpute算法,若对运行时间要求较高且数据量较大时,则应选择SoftImpute算法,同种情况下若对运行内存要求较高时,可优先考虑K近邻填补算法。结果说明不同机器学习方法在不同缺失程度的填补需求下的适用性,可应用于大豆基因组数据缺失处理。 展开更多
关键词 大豆基因组缺失 K近邻算法 SoftImpute算法 随机森林算法 全基因组关联分析
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SVM-KNN分类器——一种提高SVM分类精度的新方法 被引量:133
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作者 李蓉 叶世伟 史忠植 《电子学报》 EI CAS CSCD 北大核心 2002年第5期745-748,共4页
本文提出了一种将支持向量机分类和最近邻分类相结合的方法 ,形成了一种新的分类器 .首先对支持向量机进行分析可以看出它作为分类器实际相当于每类只选一个代表点的最近邻分类器 ,同时在对支持向量机分类时出错样本点的分布进行研究的... 本文提出了一种将支持向量机分类和最近邻分类相结合的方法 ,形成了一种新的分类器 .首先对支持向量机进行分析可以看出它作为分类器实际相当于每类只选一个代表点的最近邻分类器 ,同时在对支持向量机分类时出错样本点的分布进行研究的基础上 ,在分类阶段计算待识别样本和最优分类超平面的距离 ,如果距离差大于给定阈值直接应用支持向量机分类 ,否则代入以每类的所有的支持向量作为代表点的K近邻分类 .数值实验证明了使用支持向量机结合最近邻分类的分类器分类比单独使用支持向量机分类具有更高的分类准确率 。 展开更多
关键词 SVM-KNN分类器 SVM分类精度 支持向量机 最近邻分类 模式识别 人工智能
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一种基于稀疏表示的WLAN室内定位算法 被引量:3
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作者 曾伟 黄亮 《计算机应用与软件》 CSCD 北大核心 2014年第12期175-177,244,共4页
随着科技进步和人民生活水平的提高,越来越多的用户对定位技术需求变得日益迫切。基于WLAN的室内定位技术研究在此背景下应运而生,但是该技术容易受非视距离以及多径影响。而位置指纹算法有效地克服了上述缺点,并得到了广泛应用。提出... 随着科技进步和人民生活水平的提高,越来越多的用户对定位技术需求变得日益迫切。基于WLAN的室内定位技术研究在此背景下应运而生,但是该技术容易受非视距离以及多径影响。而位置指纹算法有效地克服了上述缺点,并得到了广泛应用。提出一种基于稀疏表示的WLAN室内定位算法,以解决位置指纹算法K近邻方法中参数选择问题、不能综合利用全局参考点信息问题,并对其进行了实验仿真。 展开更多
关键词 稀疏表示 室内定位 指纹算法 K近邻方法
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一种基于检索树的改进计数最近邻分类新算法 被引量:1
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作者 廖志芳 樊晓平 刘皛 《小型微型计算机系统》 CSCD 北大核心 2008年第2期283-287,共5页
计数最近邻分类算法是一种以数据格论为理论依据的新分类算法,其优越性在于能不经转换地处理各种混合数据.本文在阐述和分析该算法的基本原理后,发现该算法的计算效率及存储效率有待改进提高,因此我们提出了一种基于检索树的改进计数最... 计数最近邻分类算法是一种以数据格论为理论依据的新分类算法,其优越性在于能不经转换地处理各种混合数据.本文在阐述和分析该算法的基本原理后,发现该算法的计算效率及存储效率有待改进提高,因此我们提出了一种基于检索树的改进计数最近邻分类新算法,其主要思想是通过构建检索树以减少重复数据的计算量,并以此提高算法的计算效率和存储效率.通过利用国家863项目数据集和多个UCI公共数据集的综合测试,结果表明该新算法在具有大量重复数据的应用环境中效果明显,具有较高的计算和存储空间效率. 展开更多
关键词 格论 基于计数的kNN 分类算法 检索树
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