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Random forest algorithm reveals novel sites in HA protein that shift receptor binding preference of the H9N2 avian influenza virus
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作者 Yuncong Yin Wen Li +7 位作者 Rujian Chen Xiao Wang Yiting Chen Xinyuan Cui Xingbang Lu David M.Irwin Xuejuan Shen Yongyi Shen 《Virologica Sinica》 2025年第1期109-117,共9页
A switch from avian-typeα-2,3 to human-typeα-2,6 receptors is an essential element for the initiation of a pandemic from an avian influenza virus.Some H9N2 viruses exhibit a preference for binding to human-typeα-2,... A switch from avian-typeα-2,3 to human-typeα-2,6 receptors is an essential element for the initiation of a pandemic from an avian influenza virus.Some H9N2 viruses exhibit a preference for binding to human-typeα-2,6 receptors.This identifies their potential threat to public health.However,our understanding of the molecular basis for the switch of receptor preference is still limited.In this study,we employed the random forest algorithm to identify the potentially key amino acid sites within hemagglutinin(HA),which are associated with the receptor binding ability of H9N2 avian influenza virus(AIV).Subsequently,these sites were further verified by receptor binding assays.A total of 12 substitutions in the HA protein(N158D,N158S,A160 N,A160D,A160T,T163I,T163V,V190T,V190A,D193 N,D193G,and N231D)were predicted to prefer binding toα-2,6 receptors.Except for the V190T substitution,the other substitutions were demonstrated to display an affinity for preferential binding toα-2,6 receptors by receptor binding assays.Especially,the A160T substitution caused a significant upregulation of immune-response genes and an increased mortality rate in mice.Our findings provide novel insights into understanding the genetic basis of receptor preference of the H9N2 AIV. 展开更多
关键词 H9N2 Hemagglutinin(HA) Receptor binding preference random forest algorithm Host shift Interspecies transmission
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A real-time intelligent lithology identification method based on a dynamic felling strategy weighted random forest algorithm 被引量:6
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作者 Tie Yan Rui Xu +2 位作者 Shi-Hui Sun Zhao-Kai Hou Jin-Yu Feng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1135-1148,共14页
Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face ... Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face many challenges. This paper studies the problems of difficult feature information extraction,low precision of thin-layer identification and limited applicability of the model in intelligent lithologic identification. The author tries to improve the comprehensive performance of the lithology identification model from three aspects: data feature extraction, class balance, and model design. A new real-time intelligent lithology identification model of dynamic felling strategy weighted random forest algorithm(DFW-RF) is proposed. According to the feature selection results, gamma ray and 2 MHz phase resistivity are the logging while drilling(LWD) parameters that significantly influence lithology identification. The comprehensive performance of the DFW-RF lithology identification model has been verified in the application of 3 wells in different areas. By comparing the prediction results of five typical lithology identification algorithms, the DFW-RF model has a higher lithology identification accuracy rate and F1 score. This model improves the identification accuracy of thin-layer lithology and is effective and feasible in different geological environments. The DFW-RF model plays a truly efficient role in the realtime intelligent identification of lithologic information in closed-loop drilling and has greater applicability, which is worthy of being widely used in logging interpretation. 展开更多
关键词 Intelligent drilling Closed-loop drilling Lithology identification random forest algorithm Feature extraction
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Prediction of maximum upward displacement of shield tunnel linings during construction using particle swarm optimization-random forest algorithm 被引量:2
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作者 Xiaowei YE Xiaolong ZHANG +2 位作者 Yanbo CHEN Yujun WEI Yang DING 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2024年第1期1-17,共17页
During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield projects.Differential ... During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield projects.Differential floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the tunnel.In this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel excavation.The mechanism and factors causing upward movement of the tunnel lining are comprehensively summarized.Twelve input variables were selected according to results from analysis of influencing factors.The prediction performance of two models,PSO-RF and RF(default)were compared.The Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of linings.The PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings. 展开更多
关键词 random forest(rf) Particle swarm optimization(PSO) Upward displacement of lining Machine learning prediction Shieldtunneling construction
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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China 被引量:1
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作者 SHI Xiaoliang CHEN Jiajun +2 位作者 DING Hao YANG Yuanqi ZHANG Yan 《Chinese Geographical Science》 SCIE CSCD 2024年第2期342-356,共15页
Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous r... Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield. 展开更多
关键词 winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-rf) machine learning multi-source indicator optimal lead time Henan Province China
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Enhancing rock slope stability prediction using random forest machine learning:A case study
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作者 Afiqah Ismail Ahmad Safuan A Rashid +10 位作者 Ali Dehghanbanadaki Rafiuddin Hakim Roslan Mohd Firdaus Md Dan@Azlan Abd Wahid Rasib Radzuan Saari Mushairry Mustaffar Azman Kassim Rini Asnida Abdullah Khairul Hazman Padil Norbazlan Mohd Yusof Norisam Abd Rahaman 《China Geology》 2025年第4期691-706,共16页
The prediction of slope stability is a complex nonlinear problem.This paper proposes a new method based on the random forest(RF)algorithm to study the rocky slopes stability.Taking the Bukit Merah,Perak and Twin Peak(... The prediction of slope stability is a complex nonlinear problem.This paper proposes a new method based on the random forest(RF)algorithm to study the rocky slopes stability.Taking the Bukit Merah,Perak and Twin Peak(Kuala Lumpur)as the study area,the slope characteristics of geometrical parameters are obtained from a multidisciplinary approach(consisting of geological,geotechnical,and remote sensing analyses).18 factors,including rock strength,rock quality designation(RQD),joint spacing,continuity,openness,roughness,filling,weathering,water seepage,temperature,vegetation index,water index,and orientation,are selected to construct model input variables while the factor of safety(FOS)functions as an output.The area under the curve(AUC)value of the receiver operating characteristic(ROC)curve is obtained with precision and accuracy and used to analyse the predictive model ability.With a large training set and predicted parameters,an area under the ROC curve(the AUC)of 0.95 is achieved.A precision score of 0.88 is obtained,indicating that the model has a low false positive rate and correctly identifies a substantial number of true positives.The findings emphasise the importance of using a variety of terrain characteristics and different approaches to characterise the rock slope. 展开更多
关键词 Slope stability prediction random forest algorithm Remote sensing in Geology Factor of Safety(FOS) Geometrical parameters Rock quality designation(RQD) Multilayer perceptron(MLP)
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基于BPNN-EKF-GD-RF算法的锂离子电池组荷电状态估计方法
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作者 来鑫 翁嘉辉 +4 位作者 杨一鹏 孙宇飞 周龙 郑岳久 韩雪冰 《机械工程学报》 北大核心 2025年第12期251-265,共15页
锂离子电池模组的荷电状态估计(State-of-charge, SOC)是影响电池性能的一个重要内部状态,是电池组进行其它状态估计的基础。然而它的估计准确性易受温度等外部因素影响,且电池间的不一致性也为电池组中各单体电池的SOC估计带来了困难... 锂离子电池模组的荷电状态估计(State-of-charge, SOC)是影响电池性能的一个重要内部状态,是电池组进行其它状态估计的基础。然而它的估计准确性易受温度等外部因素影响,且电池间的不一致性也为电池组中各单体电池的SOC估计带来了困难。提出一种将BP神经网络(Back propagation neural network, BPNN)与扩展卡尔曼滤波(Extended Kalman filter, EKF)算法相结合的电池组SOC估计方法。该方法首先基于先验SOC利用BPNN估计不同温度下“领导者”电池的端电压,将其与实测端电压对比后采用EKF算法完成SOC后验估计,同时基于电压差采用梯度下降(Gradient descent, GD)算法更新BPNN的输出层权重使算法更快收敛。在此基础上,设计修正策略利用随机森林(Random forest, RF)算法对“跟随者”电池的SOC进行调整估计。试验结果表明,所提的BPNN-EKF-GD-RF算法能实现电池组在不同温度下SOC的准确估计,常温下SOC估计误差保持在2.5%以内,在温度变化下电池组中单体电池SOC估计最大误差不超过3.2%,为复杂环境下锂离子电池组的SOC估计提供了一种高精度低复杂度方案。 展开更多
关键词 SOC估计 BP神经网络 扩展卡尔曼滤波 梯度下降算法 随机森林 锂离子电池组
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彬长矿区煤层采动导水裂隙带高度RF-BP模型预测对比研究
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作者 姬亚东 刘譞 +5 位作者 朱开鹏 赵春虎 李凯 袁晨瀚 李盼盼 闫鹏珍 《煤矿安全》 北大核心 2025年第7期175-184,共10页
西部黄陇侏罗系煤田煤层赋存条件一般较厚,其中彬长矿区煤层厚度平均大于5 m,最厚可达14 m,且常采用综放开采工艺,造成煤层顶板导水裂隙带发育厚度大且发育规律不明,矿井涌水量居高不下,严重影响矿区安全生产。为研究彬长矿区煤矿工作... 西部黄陇侏罗系煤田煤层赋存条件一般较厚,其中彬长矿区煤层厚度平均大于5 m,最厚可达14 m,且常采用综放开采工艺,造成煤层顶板导水裂隙带发育厚度大且发育规律不明,矿井涌水量居高不下,严重影响矿区安全生产。为研究彬长矿区煤矿工作面开采扰动覆岩而导致的煤层顶板导水裂隙带发育高度,优选了煤层开采厚度、煤层埋深、顶板覆岩岩性、顶板构造特征、开采速度、工作面长度、采煤工艺等7个影响因素,通过AHP层次分析法分别计算出了上述各影响因素的权重,发现煤层开采厚度、工作面长度2个影响因素所占权重相对较大;通过Matlab对搜集的数据进行插值,使数据分布更为平滑;通过反向传播神经网络(BP)、遗传算法优化神经网络(GA-BP)、粒子群优化算法优化神经网络(PSO-BP)、随机森林(RF)算法对插值后数据进行回归拟合。研究发现,4种方法对原始数据的拟合效果都较好,其中随机森林RF相对其他模型对原始数据的拟合具有更高的准确度,训练集和测试集的均方根误差RMSE分别为0.037 41和0.055 16,决定系数R2分别为0.987 37和0.957 89。研究结果可为彬长矿区煤矿开采导水裂隙带发育高度的预测提供一定的参考。 展开更多
关键词 导水裂隙带 煤矿智能化 随机森林算法 BP神经网络 矿井涌水
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基于GWO-RF的建筑施工安全事故预测模型
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作者 王丹 潘祥莲 《中国安全科学学报》 北大核心 2025年第10期75-81,共7页
为减少建筑施工安全事故的发生,利用关联规则揭示事故关联机制,并融合优化后的随机森林(RF),预测事故发生情况。首先,以24Model为理论依据,提取388份建筑施工安全事故案例报告的致因因素;然后,采用Apriori算法挖掘事故致因因素之间的相... 为减少建筑施工安全事故的发生,利用关联规则揭示事故关联机制,并融合优化后的随机森林(RF),预测事故发生情况。首先,以24Model为理论依据,提取388份建筑施工安全事故案例报告的致因因素;然后,采用Apriori算法挖掘事故致因因素之间的相互关联作用路径;最后,利用灰狼优化算法(GWO)优化RF的超参数,构建GWO-RF建筑施工安全事故预测模型,并对事故致因因素进行特征重要性排序。结果表明:不安全行为、组织成员的安全能力、安全管理体系以及安全文化元素构成强相关条件组合;GWO能够有效优化RF的超参数,优化后建立的建筑施工安全事故预测模型(GWO-RF)预测准确率高达93.2%;特征重要性排序显示:安全教育培训对建筑施工安全事故预测的影响最大,权重为10.5%,安全融入管理、安全生产规章制度、安全生产责任制度是影响建筑施工安全事故预测的重要因素,其权重依次为7.5%、7%、6%。 展开更多
关键词 灰狼优化算法(GWO) 随机森林(rf) 建筑施工安全事故 预测模型 关联规则
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基于SCSSA-RF算法的室内可见光定位算法
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作者 陈耀 张烈平 +1 位作者 高小淋 张翠 《光通信技术》 北大核心 2025年第1期1-5,共5页
针对随机森林(RF)算法用于室内可见光定位时定位精度低,存在过拟合风险的问题,提出了一种基于正弦人口映射(SPM)与柯西分布的麻雀搜索算法(SSA)优化RF算法的室内可见光定位算法(简称SCSSA-RF算法)。首先,该算法使用采集到的接收信号强... 针对随机森林(RF)算法用于室内可见光定位时定位精度低,存在过拟合风险的问题,提出了一种基于正弦人口映射(SPM)与柯西分布的麻雀搜索算法(SSA)优化RF算法的室内可见光定位算法(简称SCSSA-RF算法)。首先,该算法使用采集到的接收信号强度值与位置坐标建立指纹数据库。然后,使用SCSSA的全局搜索能力对RF算法的关键参数进行优化,将数据输入最佳模型中进行训练。最后,将决策树的预测结果取平均值,得到待定位点的预测值。实验结果表明:SCSSA-RF算法比未改进的SSA-RF算法收敛速度更快;SCSSA-RF算法的平均定位误差为0.08 m,且误差主要集中在0.05~0.1 m内;在定位误差为0.2 m时,SCSSA-RF算法的预测准确率达到了93%。 展开更多
关键词 可见光定位 正弦人口映射 柯西分布 麻雀搜索算法 随机森林
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基于IFWA-RERF的合金600应力腐蚀裂纹扩展速率预测
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作者 骆正山 刘盈 《工业安全与环保》 2025年第9期49-55,共7页
高温环境下合金600在压力和输送介质的耦合作用下易发生应力腐蚀开裂,是合金管道的潜在失效模式,在多种影响因素共同作用下,一般参数化模型存在预测精度不高、泛化能力较差的问题,影响合金管道安全评估的准确性。将Faure序列初始种群、... 高温环境下合金600在压力和输送介质的耦合作用下易发生应力腐蚀开裂,是合金管道的潜在失效模式,在多种影响因素共同作用下,一般参数化模型存在预测精度不高、泛化能力较差的问题,影响合金管道安全评估的准确性。将Faure序列初始种群、自适应引力全局搜索、精英保留策略局部搜索引入烟花算法,使用改进烟花算法(Improved Fire War Algorithm,IFWA)对结合Lasso回归和随机森林组成的回归增强随机森林算法(Regression-Enhanced Random Forest,RERF)超参数基学习器数量(n_estimate)、树的最大深度(max_depth)寻优,以RMSE为目标值使RERF达到全局搜索和局部搜索最优,形成基于IFWA-RERF的合金600应力腐蚀裂纹扩展速率预测模型,引入MAE和R2作为模型性能评价指标,建立数据集与测试集进行对比。结果表明:使用基于IFWA-RERF的合金600应力腐蚀裂纹扩展速率预测结果最接近实际数据,预测精度和稳定性均优于其他对比模型,有助于建立准确的安全评估模型。 展开更多
关键词 合金600 裂纹扩展速率 烟花算法 随机森林算法 自适应引力
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基于RF-GA-BPNN算法的供应链风险预警研究
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作者 王红春 周子祥 《工业工程》 2025年第2期120-128,共9页
供应链系统时刻面临着来自内外部环境的多重风险与挑战,目前供应链风险预警算法在指标选取、阈值优化等方面尚存不足。为进一步提升供应链风险预警能力,关注算法融合优化及其预警效果,构建基于RF-GABPNN算法的供应链风险预警模型。该模... 供应链系统时刻面临着来自内外部环境的多重风险与挑战,目前供应链风险预警算法在指标选取、阈值优化等方面尚存不足。为进一步提升供应链风险预警能力,关注算法融合优化及其预警效果,构建基于RF-GABPNN算法的供应链风险预警模型。该模型有机结合随机森林、遗传算法、BP神经网络等多类算法的特性与优势,通过指标特征重要性筛选、初始参数优化等手段改进BP神经网络预测效果。利用中国A股3309家上市企业的风险预警指标数据集对模型进行训练与测试,结果表明RF-GA-BPNN算法在300组随机样本数据的训练下,预警准确率可达96.50%。基于RF-GA-BPNN算法的供应链风险预警模型具有较优秀的学习能力和预警能力,预测结果可为供应链风险水平的初期判断以及风险抵御措施的制定实施提供数值参考。 展开更多
关键词 供应链 风险预警 随机森林 遗传算法 BP神经网络
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基于RF和EBKRP算法的新安江流域有效土壤厚度反演 被引量:1
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作者 王尚晓 张晓东 +6 位作者 张明 牛晓楠 周墨 唐志敏 张洁 宗乐丽 徐帅 《水土保持通报》 北大核心 2025年第1期168-177,共10页
[目的]快速、准确地获取区域有效土壤厚度,分析其空间分布特征和影响因素,为植被生长、土壤保持和粮食安全工作提供理论指导。[方法]以新安江流域为研究区,将野外调查数据、地形、岩性和气候等成土因素结合起来,采用经验贝叶斯克里金回... [目的]快速、准确地获取区域有效土壤厚度,分析其空间分布特征和影响因素,为植被生长、土壤保持和粮食安全工作提供理论指导。[方法]以新安江流域为研究区,将野外调查数据、地形、岩性和气候等成土因素结合起来,采用经验贝叶斯克里金回归预测(EBKRP)和随机森林(RF)算法,得到有效土壤厚度反演结果,并分析其与环境变量之间的关系。[结果](1)区域平均有效土壤厚度为0.2~0.3 m,城镇建设集中和人类活动密集的盆地和平原区土壤厚度较高,丘陵山地区则较低。(2)从MAE(平均绝对误差)、R^(2)(判定系数)和RMSE(均方根误差)3项精度评价指标来看,RF算法的预测结果明显优于EBKRP算法,而且更能显示出土壤厚度空间异质性分布特征,在一定程度上提高了土壤厚度数字制图的效果。(3)有效土壤厚度的估算受地形和气候变量的影响较大,它们分别占变量重要性的46.77%和18.78%。[结论] RF算法能够有效实现对区域有效土壤厚度的反演,克服了土壤厚度空间异质性的特点,相较于有限采样的模型更精确,分辨率也更高。 展开更多
关键词 有效土壤厚度 随机森林(rf) 土壤数字制图 经验贝叶斯克里金回归预测(EBKRP) 新安江流域
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基于SEM和RF的和田绿洲区浅层高氟地下水水质主控因素分析与氟浓度分布预测
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作者 蒋悦 郑天亮 +3 位作者 李景吉 杨晴雯 黄振富 王双成 《安全与环境工程》 北大核心 2025年第2期264-272,共9页
高氟地下水是全球广泛分布的环境地质问题,本研究基于结构方程模型(SEM)和随机森林(RF)算法开展新疆和田绿洲区浅层高氟地下水水质主控因素及氟浓度分布预测研究。结果表明:干旱气候条件下矿物溶解(β=0.99)及离子交换作用(β=0.68)对... 高氟地下水是全球广泛分布的环境地质问题,本研究基于结构方程模型(SEM)和随机森林(RF)算法开展新疆和田绿洲区浅层高氟地下水水质主控因素及氟浓度分布预测研究。结果表明:干旱气候条件下矿物溶解(β=0.99)及离子交换作用(β=0.68)对地下水水质具有重要贡献,与地下水矿物饱和指数、氯碱指数及Gibbs模型分析结果一致;基于RF算法构建的预测模型指示浅层高氟地下水主要分布于绿洲区中部,特征变量贡献度分析表明蒸发浓缩作用以及碱性pH值条件是高氟地下水形成的重要调控因素。研究结果可为和田绿洲区浅层高氟地下水的分布预测及环境调控机制提供新认识,也可为区域安全供水战略提供指导。 展开更多
关键词 和田绿洲区 浅层高氟地下水 结构方程模型(SEM) 随机森林(rf)算法 水质评价与预测
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基于RF-Apriori算法考虑填补缺失值的高速公路事故致因分析
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作者 薛乐 于露 +2 位作者 金龙哲 李博 沈文进 《中国安全科学学报》 北大核心 2025年第4期211-218,共8页
为改善高速公路交通安全状况,以法国2018-2022年的26320条高速公路交通事故数据作为研究对象,选择3种具有代表性的算法填补数据中的缺失值,包括随机森林(RF)算法、期望最大化(EM)算法以及K最近邻(KNN)算法。并基于填补前后变量方差的变... 为改善高速公路交通安全状况,以法国2018-2022年的26320条高速公路交通事故数据作为研究对象,选择3种具有代表性的算法填补数据中的缺失值,包括随机森林(RF)算法、期望最大化(EM)算法以及K最近邻(KNN)算法。并基于填补前后变量方差的变化比较不同填补算法对数据稳定性的影响,并运用Apriori关联规则算法对完成填补的事故数据进行不同严重程度等级的高速公路事故致因分析。结果表明:经缺失值填补后,RF算法稳定性更优,相较于原始数据训练的模型准确率提高5.66%,召回率提高9.22%,F 1分数提高9.91%。客车更易引发财产损失事故的发生;摩托车在限速较低的路段易引发受伤事故,在限速较高的路段易引发死亡事故,安全设备的使用情况对事故严重程度等级有较大关系。 展开更多
关键词 随机森林(rf) APRIORI算法 缺失值 高速公路 事故致因 数据填补 关联规则
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A rapid classification method of aluminum alloy based on laser-induced breakdown spectroscopy and random forest algorithm 被引量:8
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作者 Liuyang ZHAN Xiaohong MA +4 位作者 Weiqi FANG Rui WANG Zesheng LIU Yang SONG Huafeng ZHAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期148-154,共7页
As an important non-ferrous metal structural material most used in industry and production,aluminum(Al) alloy shows its great value in the national economy and industrial manufacturing.How to classify Al alloy rapidly... As an important non-ferrous metal structural material most used in industry and production,aluminum(Al) alloy shows its great value in the national economy and industrial manufacturing.How to classify Al alloy rapidly and accurately is a significant, popular and meaningful task.Classification methods based on laser-induced breakdown spectroscopy(LIBS) have been reported in recent years. Although LIBS is an advanced detection technology, it is necessary to combine it with some algorithm to reach the goal of rapid and accurate classification. As an important machine learning method, the random forest(RF) algorithm plays a great role in pattern recognition and material classification. This paper introduces a rapid classification method of Al alloy based on LIBS and the RF algorithm. The results show that the best accuracy that can be reached using this method to classify Al alloy samples is 98.59%, the average of which is 98.45%. It also reveals through the relationship laws that the accuracy varies with the number of trees in the RF and the size of the training sample set in the RF. According to the laws, researchers can find out the optimized parameters in the RF algorithm in order to achieve,as expected, a good result. These results prove that LIBS with the RF algorithm can exactly classify Al alloy effectively, precisely and rapidly with high accuracy, which obviously has significant practical value. 展开更多
关键词 LASER-INDUCED BREAKDOWN spectroscopy(LIBS) random forest(rf) aluminum(Al)alloy classification
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基于特征选择的NGO-RF热轧H型钢水平辊轧制力预测 被引量:2
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作者 臧德宇 吴龙 +1 位作者 林太阳 潘建洲 《锻压技术》 北大核心 2025年第1期122-133,共12页
为了得到较为精确的水平辊轧制力,收集福建罗源闽光钢铁轧钢厂的实际轧制参数,并进行相关参数计算与预处理,构建包含多输入特征及多规格的H型钢水平辊轧制力数据集。为有效预测H型钢的水平辊轧制力,首先,运用孤立森林算法和树模型进行... 为了得到较为精确的水平辊轧制力,收集福建罗源闽光钢铁轧钢厂的实际轧制参数,并进行相关参数计算与预处理,构建包含多输入特征及多规格的H型钢水平辊轧制力数据集。为有效预测H型钢的水平辊轧制力,首先,运用孤立森林算法和树模型进行离群点检测与特征选择;其次,划分数据集并采用随机森林模型作为基础模型进行训练与验证;再次,应用北方苍鹰优化算法优化随机森林模型;最后,输入处理后的H型钢水平辊轧制力测试集数据,输出轧制力预测值。将所建模型(NGO-RF)与未经优化的随机森林模型、支持向量机模型、多层感知神经网络模型、卷积神经网络模型,以及经过北方苍鹰优化算法优化的支持向量机模型和多层感知神经网络模型对比,结果显示,所建模型在预测性能上优于上述所有模型,具有较高的准确性与适用性。此外,利用所建模型对H型钢588 mm×300 mm×12 mm×20 mm新规格产品的轧制力进行预测,对比模型预测值与实测值,平均误差仅为6.05%,进一步证实了所建模型能够较好地实现对H型钢水平辊轧制力的预测。 展开更多
关键词 H型钢 水平辊轧制力 随机森林 北方苍鹰优化算法 特征选择
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Prostate cancer prediction forest algorithm that takes using the random into account transrectal ultrasound findings, age, and serum levels of prostate-specific antigen 被引量:5
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作者 Li-Hong Xiao Pei-Ran Chen +4 位作者 Zhong-Ping Gou Yong-Zhong Li Mei Li Liang-Cheng Xiang Ping Feng 《Asian Journal of Andrology》 SCIE CAS CSCD 2017年第5期586-590,共5页
The aim of this study is to evaluate the ability of the random forest algorithm that combines data on transrectal ultrasound findings, age, and serum levels of prostate-specific antigen to predict prostate carcinoma. ... The aim of this study is to evaluate the ability of the random forest algorithm that combines data on transrectal ultrasound findings, age, and serum levels of prostate-specific antigen to predict prostate carcinoma. Clinico-demographic data were analyzed for 941 patients with prostate diseases treated at our hospital, including age, serum prostate-specific antigen levels, transrectal ultrasound findings, and pathology diagnosis based on ultrasound-guided needle biopsy of the prostate. These data were compared between patients with and without prostate cancer using the Chi-square test, and then entered into the random forest model to predict diagnosis. Patients with and without prostate cancer differed significantly in age and serum prostate-specific antigen levels (P 〈 0.001), as well as in all transrectal ultrasound characteristics (P 〈 0.05) except uneven echo (P = 0.609). The random forest model based on age, prostate-specific antigen and ultrasound predicted prostate cancer with an accuracy of 83.10%, sensitivity of 65.64%, and specificity of 93.83%. Positive predictive value was 86.72%, and negative predictive value was 81.64%. By integrating age, prostate-specific antigen levels and transrectal ultrasound findings, the random forest algorithm shows better diagnostic performance for prostate cancer than either diagnostic indicator on its own. This algorithm may help improve diagnosis of the disease by identifying patients at high risk for biopsy. 展开更多
关键词 diagnosis prostate cancer prostate-specific antigen random forest algorithm transrectal ultrasound characteristics
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基于BO-RF回归预测的海水柱塞泵配流阀结构参数优化研究 被引量:1
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作者 周广金 国凯 +1 位作者 孙杰 黄晓明 《机电工程》 北大核心 2025年第4期618-627,共10页
海水柱塞泵采用阀配流方式可以提高其密封性能,保证其具有较高的输出压力。针对配流阀结构参数设计不合理,导致阀芯运动滞后和容积效率降低的问题,提出了一种贝叶斯优化(BO)与随机森林算法(RF)相结合的海水柱塞泵配流阀结构参数优化方... 海水柱塞泵采用阀配流方式可以提高其密封性能,保证其具有较高的输出压力。针对配流阀结构参数设计不合理,导致阀芯运动滞后和容积效率降低的问题,提出了一种贝叶斯优化(BO)与随机森林算法(RF)相结合的海水柱塞泵配流阀结构参数优化方法。首先,利用AMESim软件搭建了海水泵液压系统仿真模型,利用试验验证了仿真模型的准确性,分别分析了吸、排液阀的弹簧刚度、弹簧预紧力、阀芯质量对阀芯滞后以及容积效率的影响;然后,基于仿真获得的配流阀结构参数与对应输出流量的数据,对比分析了贝叶斯优化随机森林(BO-RF)模型、粒子群优化随机森林(PSO-RF)模型、反向传播神经网络(BPNN)模型和随机森林(RF)模型的回归预测结果,以BO-RF模型为回归预测模型,利用遗传算法优化了配流阀结构参数,并获得了结构参数最优解;最后,对优化后的配流阀结构参数进行了仿真分析。研究结果表明:吸、排液阀的弹簧刚度、弹簧预紧力增大能够减小阀芯滞后,提高容积效率,参数增大到临界值后,容积效率会随参数增大而降低;吸、排液阀的阀芯质量增大会增大阀芯滞后,减小容积效率;BO-RF模型的均方根误差(RMSE)、平均绝对百分比误差(MAPE)、决定系数(R^(2))均优于RF、PSO-RF和BPNN模型,其回归预测准确度更高;对于优化后的结果进行仿真可得:容积效率较原结构提高了4.7%。该模型适用于配流阀结构参数预测和优化问题,可为提高柱塞泵容积效率提供参考。 展开更多
关键词 三柱塞曲柄连杆式高压海水柱塞泵 容积效率降低 阀芯运动滞后 贝叶斯优化随机森林回归预测模型 粒子群优化随机森林 弹簧刚度和预紧力 阀芯质量
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基于DBO-RF的磁场辅助镁/铝异种金属激光焊工艺 被引量:1
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作者 王新宇 周惦武 +2 位作者 赵蕾 邓乔 贺赵国 《焊接学报》 北大核心 2025年第2期72-79,共8页
为了探究磁场辅助镁/铝激光焊工艺参数和接头性能之间的关联性,并建立预测模型以指导工艺参数设计,采用试验设计方法,选取激光功率、焊接速度和磁场强度为变量,研究其对焊接接头性能的影响,并基于随机森林算法(RF)建立镁/铝对接接头的... 为了探究磁场辅助镁/铝激光焊工艺参数和接头性能之间的关联性,并建立预测模型以指导工艺参数设计,采用试验设计方法,选取激光功率、焊接速度和磁场强度为变量,研究其对焊接接头性能的影响,并基于随机森林算法(RF)建立镁/铝对接接头的预测模型,利用蜣螂算法(DBO)对模型的关键参数(树数和叶子数)进行优化.结果表明,当焊接形貌系数介于1.37~1.58时,接头性能较好;激光功率、焊接速度、磁场强度对接头性能的相对重要性分别为0.608,0.212和0.276;优化后的蜣螂优化随机森林模型(DBO-RF)在测试集上的决定系数R^(2)从0.742提升至0.950,模型的泛化能力、整体准确性和计算速度均显著提高,为磁场辅助激光焊接的工艺参数设计提供了依据. 展开更多
关键词 激光焊 镁/铝异种金属 外加磁场 蜣螂算法 随机森林
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Prediction of Permeability Using Random Forest and Genetic Algorithm Model 被引量:7
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作者 JunhuiWang Wanzi Yan +3 位作者 Zhijun Wan Yi Wang Jiakun Lv Aiping Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第12期1135-1157,共23页
Precise recovery of CoalbedMethane(CBM)based on transparent reconstruction of geological conditions is a branch of intelligent mining.The process of permeability reconstruction,ranging from data perception to real-tim... Precise recovery of CoalbedMethane(CBM)based on transparent reconstruction of geological conditions is a branch of intelligent mining.The process of permeability reconstruction,ranging from data perception to real-time data visualization,is applicable to disaster risk warning and intelligent decision-making on gas drainage.In this study,a machine learning method integrating the Random Forest(RF)and the Genetic Algorithm(GA)was established for permeability prediction in the Xishan Coalfield based on Uniaxial Compressive Strength(UCS),effective stress,temperature and gas pressure.A total of 50 sets of data collected by a self-developed apparatus were used to generate datasets for training and validating models.Statistical measures including the coefficient of determination(R2)and Root Mean Square Error(RMSE)were selected to validate and compare the predictive performances of the single RF model and the hybrid RF–GA model.Furthermore,sensitivity studies were conducted to evaluate the importance of input parameters.The results show that,the proposed RF–GA model is robust in predicting the permeability;UCS is directly correlated to permeability,while all other inputs are inversely related to permeability;the effective stress exerts the greatest impact on permeability based on importance score,followed by the temperature(or gas pressure)and UCS.The partial dependence plots,indicative of marginal utility of each feature in permeability prediction,are in line with experimental results.Thus,the proposed hybrid model(RF–GA)is capable of predicting permeability and thus beneficial to precise CBMrecovery. 展开更多
关键词 PERMEABILITY machine learning random forest genetic algorithm coalbed methane recovery
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