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Integrated classification method of tight sandstone reservoir based on principal component analysise simulated annealing genetic algorithmefuzzy cluster means 被引量:3
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作者 Bo-Han Wu Ran-Hong Xie +3 位作者 Li-Zhi Xiao Jiang-Feng Guo Guo-Wen Jin Jian-Wei Fu 《Petroleum Science》 SCIE EI CSCD 2023年第5期2747-2758,共12页
In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tig... In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic parameters.The PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as input.The unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological profiles.The analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method. 展开更多
关键词 Tight sandstone Integrated reservoir classification principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means
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Polarimetric Meteorological Satellite Data Processing Software Classification Based on Principal Component Analysis and Improved K-Means Algorithm 被引量:1
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作者 Manyun Lin Xiangang Zhao +3 位作者 Cunqun Fan Lizi Xie Lan Wei Peng Guo 《Journal of Geoscience and Environment Protection》 2017年第7期39-48,共10页
With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In th... With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In this paper, a set of software classification method based on software operating characteristics is proposed. The method uses software run-time resource consumption to describe the software running characteristics. Firstly, principal component analysis (PCA) is used to reduce the dimension of software running feature data and to interpret software characteristic information. Then the modified K-means algorithm was used to classify the meteorological data processing software. Finally, it combined with the results of principal component analysis to explain the significance of various types of integrated software operating characteristics. And it is used as the basis for optimizing the allocation of software hardware resources and improving the efficiency of software operation. 展开更多
关键词 principal component analysis Improved K-Mean algorithm METEOROLOGICAL Data Processing FEATURE analysis SIMILARITY algorithm
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Improved Face Recognition Method Using Genetic Principal Component Analysis 被引量:2
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作者 E.Gomathi K.Baskaran 《Journal of Electronic Science and Technology》 CAS 2010年第4期372-378,共7页
An improved face recognition method is proposed based on principal component analysis (PCA) compounded with genetic algorithm (GA), named as genetic based principal component analysis (GPCA). Initially the eigen... An improved face recognition method is proposed based on principal component analysis (PCA) compounded with genetic algorithm (GA), named as genetic based principal component analysis (GPCA). Initially the eigenspace is created with eigenvalues and eigenvectors. From this space, the eigenfaces are constructed, and the most relevant eigenfaees have been selected using GPCA. With these eigenfaees, the input images are classified based on Euclidian distance. The proposed method was tested on ORL (Olivetti Research Labs) face database. Experimental results on this database demonstrate that the effectiveness of the proposed method for face recognition has less misclassification in comparison with previous methods. 展开更多
关键词 EIGENFACES EIGENVECTORS face recognition genetic algorithm principal component analysis.
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Aerodynamic multi-objective integrated optimization based on principal component analysis 被引量:13
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作者 Jiangtao HUANG Zhu ZHOU +2 位作者 Zhenghong GAO Miao ZHANG Lei YU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第4期1336-1348,共13页
Based on improved multi-objective particle swarm optimization(MOPSO) algorithm with principal component analysis(PCA) methodology, an efficient high-dimension multiobjective optimization method is proposed, which,... Based on improved multi-objective particle swarm optimization(MOPSO) algorithm with principal component analysis(PCA) methodology, an efficient high-dimension multiobjective optimization method is proposed, which, as the purpose of this paper, aims to improve the convergence of Pareto front in multi-objective optimization design. The mathematical efficiency,the physical reasonableness and the reliability in dealing with redundant objectives of PCA are verified by typical DTLZ5 test function and multi-objective correlation analysis of supercritical airfoil,and the proposed method is integrated into aircraft multi-disciplinary design(AMDEsign) platform, which contains aerodynamics, stealth and structure weight analysis and optimization module.Then the proposed method is used for the multi-point integrated aerodynamic optimization of a wide-body passenger aircraft, in which the redundant objectives identified by PCA are transformed to optimization constraints, and several design methods are compared. The design results illustrate that the strategy used in this paper is sufficient and multi-point design requirements of the passenger aircraft are reached. The visualization level of non-dominant Pareto set is improved by effectively reducing the dimension without losing the primary feature of the problem. 展开更多
关键词 Aerodynamic optimization Dimensional reduction Improved multi-objective particle swarm optimization(MOPSO) algorithm Multi-objective principal component analysis
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Support vector classifier based on principal component analysis 被引量:1
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作者 Zheng Chunhong Jiao Licheng Li Yongzhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期184-190,共7页
Support vector classifier(SVC)has the superior advantages for small sample learning problems with high dimensions,with especially better generalization ability.However there is some redundancy among the high dimension... Support vector classifier(SVC)has the superior advantages for small sample learning problems with high dimensions,with especially better generalization ability.However there is some redundancy among the high dimensions of the original samples and the main features of the samples may be picked up first to improve the performance of SVC.A principal component analysis(PCA)is employed to reduce the feature dimensions of the original samples and the pre-selected main features efficiently,and an SVC is constructed in the selected feature space to improve the learning speed and identification rate of SVC.Furthermore,a heuristic genetic algorithm-based automatic model selection is proposed to determine the hyperparameters of SVC to evaluate the performance of the learning machines.Experiments performed on the Heart and Adult benchmark data sets demonstrate that the proposed PCA-based SVC not only reduces the test time drastically,but also improves the identify rates effectively. 展开更多
关键词 support vector classifier principal component analysis feature selection genetic algorithms
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Generalized two-dimensional correlation near-infrared spectroscopy and principal component analysis of the structures of methanol and ethanol 被引量:6
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作者 Liu Hao Xu JianPing +1 位作者 Qu LingBo Xiang BingRen 《Science China Chemistry》 SCIE EI CAS 2010年第5期1154-1159,共6页
Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal c... Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal component analysis) . First,the FT-NIR spectra were measured over a temperature range of 30-64(or 30-71) °C,and then the 2D correlation spectra were computed.Combining near-infrared spectroscopy,generalized 2D correlation spectroscopy,and references,we analyzed the molecular structures(especially the hydrogen bond) of methanol and ethanol,and performed the NIR band assignments. The PCA method was employed to verify the results of the 2D analysis.This study will be helpful to the understanding of these reagents. 展开更多
关键词 NIR(near-infrared) two-dimensional (2D) CORRELATION spectroscopy principal component analysis (PCA) METHANOL ETHANOL
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Kernel Factor Analysis Algorithm with Varimax
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作者 夏国恩 金炜东 张葛祥 《Journal of Southwest Jiaotong University(English Edition)》 2006年第4期394-399,共6页
Kernal factor analysis (KFA) with vafimax was proposed by using Mercer kernel function which can map the data in the original space to a high-dimensional feature space, and was compared with the kernel principle com... Kernal factor analysis (KFA) with vafimax was proposed by using Mercer kernel function which can map the data in the original space to a high-dimensional feature space, and was compared with the kernel principle component analysis (KPCA). The results show that the best error rate in handwritten digit recognition by kernel factor analysis with vadmax (4.2%) was superior to KPCA (4.4%). The KFA with varimax could more accurately image handwritten digit recognition. 展开更多
关键词 Kernel factor analysis Kernel principal component analysis Support vector machine Varimax algorithm Handwritten digit recognition
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Convergence of algorithms used for principal component analysis 被引量:1
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作者 张俊华 陈翰馥 《Science China(Technological Sciences)》 SCIE EI CAS 1997年第6期597-604,共8页
The convergence of algorithms used for principal component analysis is analyzed. The algorithms are proved to converge to eigenvectors and eigenvalues of a matrix A which is the expectation of observed random samples.... The convergence of algorithms used for principal component analysis is analyzed. The algorithms are proved to converge to eigenvectors and eigenvalues of a matrix A which is the expectation of observed random samples. The conditions required here are considerably weaker than those used in previous work. 展开更多
关键词 principal component analysis STOCHASTIC APPROXIMATION algorithmS convergence.
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Coal and gas outburst prediction model based on principal component analysis and improved support vector machine 被引量:5
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作者 Chaojun Fan Xinfeng Lai +1 位作者 Haiou Wen Lei Yang 《Geohazard Mechanics》 2023年第4期319-324,共6页
In order to predict the coal outburst risk quickly and accurately,a PCA-FA-SVM based coal and gas outburst risk prediction model was designed.Principal component analysis(PCA)was used to pre-process the original data ... In order to predict the coal outburst risk quickly and accurately,a PCA-FA-SVM based coal and gas outburst risk prediction model was designed.Principal component analysis(PCA)was used to pre-process the original data samples,extract the principal components of the samples,use firefly algorithm(FA)to improve the support vector machine model,and compare and analyze the prediction results of PCA-FA-SVM model with BP model,FA-SVM model,FA-BP model and SVM model.Accuracy rate,recall rate,Macro-F1 and model prediction time were used as evaluation indexes.The results show that:Principal component analysis improves the prediction efficiency and accuracy of FA-SVM model.The accuracy rate of PCA-FA-SVM model predicting coal and gas outburst risk is 0.962,recall rate is 0.955,Macro-F1 is 0.957,and model prediction time is 0.312s.Compared with other models,The comprehensive performance of PCA-FA-SVM model is better. 展开更多
关键词 Coal and gas outburst Risk prediction principal component analysis(PCA) Firefly algorithm(FA) Support vector machine(SVM)
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Principal component cluster analysis of ECG time series based on Lyapunov exponent spectrum 被引量:4
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作者 WANGNai RUANJiong 《Chinese Science Bulletin》 SCIE EI CAS 2004年第18期1980-1985,共6页
In this paper we propose an approach of prin-cipal component cluster analysis based on Lyapunov expo-nent spectrum (LES) to analyze the ECG time series. Analy-sis results of 22 sample-files of ECG from the MIT-BIH da-... In this paper we propose an approach of prin-cipal component cluster analysis based on Lyapunov expo-nent spectrum (LES) to analyze the ECG time series. Analy-sis results of 22 sample-files of ECG from the MIT-BIH da-tabase confirmed the validity of our approach. Another technique named improved teacher selecting student (TSS) algorithm is presented to analyze unknown samples by means of some known ones, which is of better accuracy. This technique combines the advantages of both statistical and nonlinear dynamical methods and is shown to be significant to the analysis of nonlinear ECG time series. 展开更多
关键词 ECG 非线性时间级数分析 李雅普诺夫指数光谱 TSS算法 主要成份聚合分析
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Research on Application of Enhanced Neural Networks in Software Risk Analysis
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作者 Zhenbang Rong Juhua Chen +1 位作者 Mei Liu Yong Hu 《南昌工程学院学报》 CAS 2006年第2期112-116,121,共6页
This paper puts forward a risk analysis model for software projects using enranced neural networks.The data for analysis are acquired through questionnaires from real software projects. To solve the multicollinearity ... This paper puts forward a risk analysis model for software projects using enranced neural networks.The data for analysis are acquired through questionnaires from real software projects. To solve the multicollinearity in software risks, the method of principal components analysis is adopted in the model to enhance network stability.To solve uncertainty of the neural networks structure and the uncertainty of the initial weights, genetic algorithms is employed.The experimental result reveals that the precision of software risk analysis can be improved by using the erhanced neural networks model. 展开更多
关键词 software risk analysis principal components analysis back propagation neural networks genetic algorithms
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Prediction of coal and gas outburst hazard using kernel principal component analysis and an enhanced extreme learning machine approach
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作者 Kailong Xue Yun Qi +2 位作者 Hongfei Duan Anye Cao Aiwen Wang 《Geohazard Mechanics》 2024年第4期279-288,共10页
In order to enhance the accuracy and efficiency of coal and gas outburst prediction,a novel approach combining Kernel Principal Component Analysis(KPCA)with an Improved Whale Optimization Algorithm(IWOA)optimized extr... In order to enhance the accuracy and efficiency of coal and gas outburst prediction,a novel approach combining Kernel Principal Component Analysis(KPCA)with an Improved Whale Optimization Algorithm(IWOA)optimized extreme learning machine(ELM)is proposed for precise forecasting of coal and gas outburst disasters in mines.Firstly,based on the influencing factors of coal and gas outburst disasters,nine coupling indexes are selected,including gas pressure,geological structure,initial velocity of gas emission,and coal structure type.The correlation between each index was analyzed using the Pearson correlation coefficient matrix in SPSS 27,followed by extraction of the principal components of the original data through Kernel Principal Component Analysis(KPCA).The Whale Optimization Algorithm(WOA)was enhanced by incorporating adaptive weight,variable helix position update,and optimal neighborhood disturbance to augment its performance.The improved Whale Optimization Algorithm(IWOA)is subsequently employed to optimize the weight Φ of the Extreme Learning Machine(ELM)input layer and the threshold g of the hidden layer,thereby enhancing its predictive accuracy and mitigating the issue of"over-fitting"associated with ELM to some extent.The principal components extracted by KPCA were utilized as input,while the outburst risk grade served as output.Subsequently,a comparative analysis was conducted between these results and those obtained from WOA-SVC,PSO-BPNN,and SSA-RF models.The IWOA-ELM model accurately predicts the risk grade of coal and gas outburst disasters,with results consistent with actual situations.Compared to other models tested,the model's performance showed an increase in Ac by 0.2,0.3,and 0.2 respectively;P increased by 0.15,0.2167,and 0.1333 respectively;R increased by 0.25,0.3,and 0.2333 respectively;F1-Score increased by 0.2031,0.2607,and 0.1864 respectively;Kappa coefficient k increased by 0.3226,0.4762 and 0.3175,respectively.The practicality and stability of the IWOAELM model were verified through its application in a coal mine in Shanxi Province where the predicted values exactly matched the actual values.This indicates that this model is more suitable for predicting coal and gas outburst disaster risks. 展开更多
关键词 Coal and gas outburst Risk prediction Kernel principal component analysis(KPCA) Improved whale optimization algorithm(IWOA) Extreme learning machine(ELM)
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基于数据驱动的Al-Cu合金多目标性能模型预测
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作者 廉红珍 陆春月 《航空材料学报》 北大核心 2026年第3期47-55,共9页
铸造铝合金因其优异的力学性能广泛应用于航空航天、汽车等领域,但传统合金设计面临成分空间庞大、试错实验成本高和成分与性能之间非线性关系难以预测的问题。本工作提出一种反向传播神经网络、主成分分析和遗传算法相结合的机器学习模... 铸造铝合金因其优异的力学性能广泛应用于航空航天、汽车等领域,但传统合金设计面临成分空间庞大、试错实验成本高和成分与性能之间非线性关系难以预测的问题。本工作提出一种反向传播神经网络、主成分分析和遗传算法相结合的机器学习模型,用于铸造铝合金的多目标性能预测。该模型通过反向传播神经网络非线性映射建立合金成分与性能的关系、主成分分析降维、遗传算法优化网络参数,从而提升预测精度和训练效率。结果表明,优化后的模型均方误差、决定系数和平均绝对误差分别为36.28、0.91和2.44,在极限抗拉强度、屈服强度和断后伸长率的实验验证中,预测值与实验值控制在±5%误差范围内,具有较高预测精度,证明该模型具有高效性与可靠性。 展开更多
关键词 铸造铝合金 主成分分析 反向传播神经网络 遗传算法 力学性能
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基于模态分析和PCA-WOA-RF的磨煤机下架体壳振预测
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作者 赵小惠 刘磊 +3 位作者 蒲军平 成小乐 高畅 胡胜 《山东大学学报(工学版)》 北大核心 2026年第1期149-157,168,共10页
为探究磨煤机下架体壳振与其他运行参数之间的复杂非线性映射关系,并提高磨煤机下架体壳振预测的准确性,提出一种基于PCA-WOA-RF模型的磨煤机下架体壳振预测方法。对磨煤机下架体进行模态分析,验证下架体壳振标准值,使用Spearman相关系... 为探究磨煤机下架体壳振与其他运行参数之间的复杂非线性映射关系,并提高磨煤机下架体壳振预测的准确性,提出一种基于PCA-WOA-RF模型的磨煤机下架体壳振预测方法。对磨煤机下架体进行模态分析,验证下架体壳振标准值,使用Spearman相关系数法和主成分分析法(principal component analysis,PCA)对磨煤机工作数据进行相关性分析并提取主成分;以随机森林(random forest,RF)为预测模型结构基础,使用鲸鱼优化算法(whale optimization algorithm,WOA)对模型的超参数进行优化;以国能长源武汉青山热电有限公司磨煤机工作数据进行实例验证,并与PCA-BP、PCA-SVM和PCA-RF模型进行精度对比。结果表明:一次风流量、拉杆应变、磨煤机电机轴振动、中架体壳振、煤量和一次风出入口差压与磨煤机下架体壳振有显著相关性,经过主成分分析法提取的2个主成分方差贡献率达94.569%,所提出的PCA-WOA-RF模型平均预测误差最小,预测精度达到97.80%。该模型进一步提升了磨煤机下架体壳振预测精度。 展开更多
关键词 磨煤机 下架体壳振 主成分分析 随机森林 鲸鱼优化算法
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基于改进鱼鹰优化算法及其在短期网络流量异常检测中的应用
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作者 高翔 赵梦玲 殷新宇 《云南大学学报(自然科学版)》 北大核心 2026年第2期227-239,共13页
为了有效处理网络流量数据的随机性和不稳定性对数据传输的影响,首先通过主成分分析(principal component analysis,PCA)对网络流量数据进行特征降维,以提升数据的质量和稳定性;其次,引入Tent混沌映射、动态反向学习和自适应步长策略对... 为了有效处理网络流量数据的随机性和不稳定性对数据传输的影响,首先通过主成分分析(principal component analysis,PCA)对网络流量数据进行特征降维,以提升数据的质量和稳定性;其次,引入Tent混沌映射、动态反向学习和自适应步长策略对鱼鹰优化算法进行改进,改进后的鱼鹰优化算法(improved osprey optimization algorithm,IOOA)提高了全局搜索能力和局部搜索精度,同时增强了跳出局部最优值的能力;然后,使用改进鱼鹰优化算法精细优化深度极限学习机(deep extreme learning machine,DELM)参数;再次,构建PCA-IOOA-DELM多步短期网络流量异常检测模型;最后,将该模型用于网络流量的分类与异常检测.仿真实验结果表明,相较于其它检测模型,提出的PCA-IOOA-DELM检测模型在短期网络流量异常检测的准确性和精确度方面均展现出显著优势,有效地提高了异常流量的识别能力. 展开更多
关键词 改进鱼鹰优化算法 深度极限学习机 短期网络流量异常 主成分分析
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基于改进支持向量机的有源配电网单相断线故障检测方法
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作者 吴宇轩 欧阳森 +3 位作者 杨向宇 陈汉栋 黎人玮 廖键 《发电技术》 2026年第1期185-194,共10页
【目的】断线故障的及时、准确检测对保障配电网的正常安全运行至关重要,而目前的单相断线故障检测的传统判据在有源配电网中的应用存在一定的局限性,因此,提出了一种基于改进支持向量机对多种电气特征量进行融合的单相断线故障检测方... 【目的】断线故障的及时、准确检测对保障配电网的正常安全运行至关重要,而目前的单相断线故障检测的传统判据在有源配电网中的应用存在一定的局限性,因此,提出了一种基于改进支持向量机对多种电气特征量进行融合的单相断线故障检测方法。【方法】首先,建立了兼具启动判据、传统判据、有源判据的电气特征量指标体系。其次,通过开关量化法对启动判据进行处理。然后,通过核主成分分析方法从启动判据以外的特征指标体系中筛除低贡献率的特征指标。最后,将降维后的数据输入支持向量机,通过麻雀搜索算法完成支持向量机参数优化,得到断线故障检测模型。【结果】在改进IEEE15节点模型上进行的仿真算例表明,所提方法可将有效实现特征量的降维,较单一判据提升了8.87%的检测准确率。【结论】该方法解决了单相断线故障检测的传统判据容易失效的问题,能有效完成不同场景下的故障检测。 展开更多
关键词 有源配电网 单相断线 支持向量机 麻雀搜索算法 核主成分分析
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基于机器学习的水稻始穗期预测方法
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作者 任义方 朱凤 陈思宁 《中国农业气象》 2026年第4期558-571,共14页
水稻始穗期是稻曲病、穗稻瘟、纹枯病等病害病菌侵入谷粒等器官造成稻米品质降低产量减少的关键期。为提高水稻病害防治针对性,更好满足“预防为主,综合防治,绿色控害,减药增效”的要求,本文以江苏单季稻为例,利用历史气象资料和水稻生... 水稻始穗期是稻曲病、穗稻瘟、纹枯病等病害病菌侵入谷粒等器官造成稻米品质降低产量减少的关键期。为提高水稻病害防治针对性,更好满足“预防为主,综合防治,绿色控害,减药增效”的要求,本文以江苏单季稻为例,利用历史气象资料和水稻生育期观测资料,在分析水稻始穗期特征及其关键影响因子基础上,应用主成分分析法(PCA)、误差反向传播神经网络算法(BP)、随机森林算法(RF)研究水稻始穗期的预估方法。设置4组模拟方案分别建立水稻始穗期预测模型,以决定系数、均方根误差作为评判指标,对模型精度及其普适性进行分析评价。结果表明:苏北、苏中、苏南地区水稻始穗期的跨度分别在8月4−31日、8月9日−9月18日和8月16日−9月20日,各区平均标准差分别为4d、6d和5d;江苏各区影响水稻始穗期的关键因子基本一致,水稻始穗前3个生育期日序最为关键,播种−分蘖、分蘖−拔节、拔节−孕穗三个生育阶段的温度类因子重要性明显大于降水和日照类因子;与基于RF算法模型相比,基于BP算法的模型模拟精度更高,且对PCA处理后消除相关性的预测因子具有更好的“接纳性”,对江苏各区水稻始穗期模拟预测误差均在2d以内,预测提前量在10d左右,可为准确把握水稻病害防治关键期提供技术支撑。 展开更多
关键词 水稻 始穗期 主成分分析 随机森林算法 误差反向传播神经网络算法
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基于PCA和GPSO-BP神经网络的钢轨闪光焊接头灰斑面积预测
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作者 刘新 王晓 +2 位作者 吕其兵 郝美琪 谭洪涛 《焊接》 2026年第2期22-29,38,共9页
【目的】钢轨闪光焊接头灰斑面积的准确预测对于钢轨焊接质量评价具有重要意义,该文旨在提高焊接接头灰斑面积预测精度。【方法】提出了一种基于主成分分析(Principal component analysis, PCA)和改进的粒子群算法(Genetic algorithm im... 【目的】钢轨闪光焊接头灰斑面积的准确预测对于钢轨焊接质量评价具有重要意义,该文旨在提高焊接接头灰斑面积预测精度。【方法】提出了一种基于主成分分析(Principal component analysis, PCA)和改进的粒子群算法(Genetic algorithm improved particle swarm optimization algorithm, GPSO)优化反向传播(Back propagation, BP)神经网络的焊接接头灰斑面积预测模型。采用PCA对影响灰斑面积的特征量进行降维处理,去除原始数据中包含的冗余信息,以PCA提取的辅助变量作为预测模型的输入;利用GPSO算法优化BP神经网络的初始权值和阈值,建立了PCA-GPSO-BP神经网络钢轨闪光焊接头灰斑面积预测模型;结合实例数据进行预测并分别与传统BP,PCA-BP,PCA-PSO-BP模型进行对比分析。【结果】结果表明,PCA-GPSO-BP模型在MAX,MAE,RMSE 3项误差指标上较传统BP模型分别减小了50.97%,68.51%,62.43%,测试样本中灰斑面积预测值和实际值间的相关系数达到0.995 6。【结论】PCA-GPSO-BP模型能够有效提高钢轨闪光焊接头灰斑面积预测精度,具有重要的工程应用价值。 展开更多
关键词 闪光焊 灰斑面积预测 主成分分析 改进的粒子群算法 神经网络
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Cooperative Metaheuristics with Dynamic Dimension Reduction for High-Dimensional Optimization Problems
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作者 Junxiang Li Zhipeng Dong +2 位作者 Ben Han Jianqiao Chen Xinxin Zhang 《Computers, Materials & Continua》 2026年第1期1484-1502,共19页
Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when ta... Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems. 展开更多
关键词 Dimension reduction modified principal components analysis high-dimensional optimization problems cooperative metaheuristics metaheuristic algorithms
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重尾过程下部分函数型可加线性回归模型的贝叶斯估计
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作者 卢哲昕 李鑫 +1 位作者 徐萍 王纯杰 《统计与决策》 北大核心 2026年第2期38-43,共6页
文章针对重尾过程下的部分函数型可加线性回归模型(PFALM)提出了一个稳健贝叶斯估计方法,其中,响应变量服从SMN分布;采用函数型主成分分析方法对函数型斜率函数进行基展开,采用B-样条逼近可加函数,通过推导参数的后验分布并利用MCMC算... 文章针对重尾过程下的部分函数型可加线性回归模型(PFALM)提出了一个稳健贝叶斯估计方法,其中,响应变量服从SMN分布;采用函数型主成分分析方法对函数型斜率函数进行基展开,采用B-样条逼近可加函数,通过推导参数的后验分布并利用MCMC算法得到未知参数的估计。模拟研究结果表明,所提方法不易受厚尾分布或异常值的影响,具有稳健性。 展开更多
关键词 函数型数据 部分函数型可加线性回归模型 SMN分布 函数型主成分分析 MCMC算法
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