期刊文献+
共找到7,559篇文章
< 1 2 250 >
每页显示 20 50 100
Stress-assisted corrosion mechanism of 3Ni steel by using gradient boosting decision tree machining learning method 被引量:2
1
作者 Xiaojia Yang Jinghuan Jia +5 位作者 Qing Li Renzheng Zhu Jike Yang Zhiyong Liu Xuequn Cheng Xiaogang Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1311-1321,共11页
Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for st... Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for strength enhancement becoming a trend.The stress-assisted corrosion behavior of a novel designed high-strength 3Ni steel was investigated in the current study using the corrosion big data method.The information on the corrosion process was recorded using the galvanic corrosion current monitoring method.The gradi-ent boosting decision tree(GBDT)machine learning method was used to mine the corrosion mechanism,and the importance of the struc-ture factor was investigated.Field exposure tests were conducted to verify the calculated results using the GBDT method.Results indic-ated that the GBDT method can be effectively used to study the influence of structural factors on the corrosion process of 3Ni steel.Dif-ferent mechanisms for the addition of Mn and Cu to the stress-assisted corrosion of 3Ni steel suggested that Mn and Cu have no obvious effect on the corrosion rate of non-stressed 3Ni steel during the early stage of corrosion.When the corrosion reached a stable state,the in-crease in Mn element content increased the corrosion rate of 3Ni steel,while Cu reduced this rate.In the presence of stress,the increase in Mn element content and Cu addition can inhibit the corrosion process.The corrosion law of outdoor-exposed 3Ni steel is consistent with the law based on corrosion big data technology,verifying the reliability of the big data evaluation method and data prediction model selection. 展开更多
关键词 weathering steel stress-assisted corrosion gradient boosting decision tree machining learning
下载PDF
Impact Damage Testing Study of Shanxi-Beijing Natural Gas Pipeline Based on Decision Tree Rotary Tiller Operation
2
作者 Liqiong Chen Kai Zhang +4 位作者 Song Yang Duo Xu Weihe Huang Hongxuan Hu Haonan Liu 《Structural Durability & Health Monitoring》 EI 2024年第5期683-706,共24页
The North China Plain and the agricultural region are crossed by the Shanxi-Beijing natural gas pipeline.Resi-dents in the area use rototillers for planting and harvesting;however,the depth of the rototillers into the... The North China Plain and the agricultural region are crossed by the Shanxi-Beijing natural gas pipeline.Resi-dents in the area use rototillers for planting and harvesting;however,the depth of the rototillers into the ground is greater than the depth of the pipeline,posing a significant threat to the safe operation of the pipeline.Therefore,it is of great significance to study the dynamic response of rotary tillers impacting pipelines to ensure the safe opera-tion of pipelines.This article focuses on the Shanxi-Beijing natural gas pipeline,utilizingfinite element simulation software to establish afinite element model for the interaction among the machinery,pipeline,and soil,and ana-lyzing the dynamic response of the pipeline.At the same time,a decision tree model is introduced to classify the damage of pipelines under different working conditions,and the boundary value and importance of each influen-cing factor on pipeline damage are derived.Considering the actual conditions in the hemp yam planting area,targeted management measures have been proposed to ensure the operational safety of the Shanxi-Beijing natural gas pipeline in this region. 展开更多
关键词 Natural gas pipeline rotary tiller operation third-party damage finite element simulation decision tree model safety management
下载PDF
基于Decision Trees的配电网中性点不接地系统选线
3
作者 黄贤明 冯兆 《云南电业》 2024年第1期6-10,18,共6页
针对配电网中性点不接地系统,使用录波数据解决单相接地选线不准的难题,提出了基于Decision Trees算法进行单相接地选线的方法.使用PSCAD仿真10kV配电网单相接地故障得到录波数据,转换成通用格式,提取稳态数据并进行预处理,通过对比多... 针对配电网中性点不接地系统,使用录波数据解决单相接地选线不准的难题,提出了基于Decision Trees算法进行单相接地选线的方法.使用PSCAD仿真10kV配电网单相接地故障得到录波数据,转换成通用格式,提取稳态数据并进行预处理,通过对比多个机器学习分类算法,选择基于Decision Trees算法进行单相接地选线.选择的Decision Trees算法训练准确度高达99.99%,且模型小,训练速度快.将训练后的模型导出,使用实际的故障录波数据进行验证,选线准确度高达95%以上.结果表明该方法易于实现,准确度高,适合在实际中应用. 展开更多
关键词 中性点不接地系统 decision trees 单相接地选线 机器学习
下载PDF
Study on Crops Classification Based on Multi-spectral Image and Decision Tree Method 被引量:2
4
作者 刘磊 江东 +1 位作者 徐敏 尹芳 《Agricultural Science & Technology》 CAS 2011年第11期1703-1706,1710,共5页
[Objective] The aim was to explore the feasibility of using single spectrum image to classify crops based on multi-spectral image and Decision Tree Method. [Method] Taking the typical agriculture plantation area in Hu... [Objective] The aim was to explore the feasibility of using single spectrum image to classify crops based on multi-spectral image and Decision Tree Method. [Method] Taking the typical agriculture plantation area in Hulunbeier area, according to field measured spectrum data, the optimum time of main crops, barley, wheat, rapeseed, based on crops spectrum characteristics, by dint of decision-making tree method, and considering spectral matching method, classification of crops was studied such as SAM. [Result] By dint of Landsat TM image gained in the first half of August, based on geographic and atmospheric proof-reading, decision-making tree was constructed. Plantation information about wheat, barley, and rapeseed and plantation grassland was extracted successfully. The general classification accuracy reached 86.90%. Kappa coefficient was 0.831 1. [Conclusion] Taking typical spectrum image as data source, and applying Decision Tree Method to get crops type's information had fine application future. 展开更多
关键词 Remote sensing PHENOLOGY decision tree Crop type
下载PDF
Study on Extracting Information about Settlements Distribution in Western Jilin Province Based on Decision Tree Model 被引量:1
5
作者 连懿 陈圣波 +1 位作者 王亚楠 逄超 《Journal of Landscape Research》 2010年第2期92-95,共4页
With western Jilin Province as the study region, spectral characteristics and texture features of remote sensing images were taken as the classification basis to construct a Decision Tree Model and extract information... With western Jilin Province as the study region, spectral characteristics and texture features of remote sensing images were taken as the classification basis to construct a Decision Tree Model and extract information about settlements in western Jilin Province, and the manually-extracted information about settlements in western Jilin Province was evaluated by confusion matrix. The results showed that Decision Tree Model was convenient for extracting settlements information by integrating spectral and texture features, and the accuracy of such a method was higher than that of the traditional Maximum Liklihood Method, in addition, calculation methods of extracting settlements information by this mean were concluded. 展开更多
关键词 SETTLEMENTS TM Western Jilin Province Spectral characteristics Texture features decision tree Confusion matrix
下载PDF
Forecasting Model of Agro-meteorological Disaster Grade Based on Decision Tree 被引量:2
6
作者 司巧梅 《Meteorological and Environmental Research》 CAS 2010年第2期85-87,90,共4页
Based on the discuss of the basic concept of data mining technology and the decision tree method,combining with the data samples of wind and hailstorm disasters in some counties of Mudanjiang region,the forecasting mo... Based on the discuss of the basic concept of data mining technology and the decision tree method,combining with the data samples of wind and hailstorm disasters in some counties of Mudanjiang region,the forecasting model of agro-meteorological disaster grade was established by adopting the C4.5 classification algorithm of decision tree,which can forecast the direct economic loss degree to provide rational data mining model and obtain effective analysis results. 展开更多
关键词 Data mining Agro-meteorology decision tree C4.5 algorithm Classification mining China
下载PDF
基于Elastic Net-Decision Tree的垃圾邮件过滤研究
7
作者 衷路生 刘庆雄 +1 位作者 龚锦红 张永贤 《科学技术与工程》 北大核心 2015年第32期59-64,共6页
针对垃圾邮件文本数据高维、稀疏及词条相关等特点,提出Elastic Net-Decision Tree(EN-DT)两步分类算法。第一步,利用Elastic Net提取邮件文本特征变量,将高维文本数据降至低维。第二步,将所提取的低维特征变量输入到Decision Tree中进... 针对垃圾邮件文本数据高维、稀疏及词条相关等特点,提出Elastic Net-Decision Tree(EN-DT)两步分类算法。第一步,利用Elastic Net提取邮件文本特征变量,将高维文本数据降至低维。第二步,将所提取的低维特征变量输入到Decision Tree中进行邮件分类。根据分类评价指标对分类结果进行评价。利用Mark Hopkins等人收集的Spam邮件文本数据进行仿真,实验结果表明相比于PLS、PCA和Lasso等算法EN-DT分类性能更佳。 展开更多
关键词 垃圾邮件 ELASTIC NET 决策树
下载PDF
Application of Clustering-based Decision Tree in the Screening of Maize Germplasm 被引量:2
8
作者 王斌 《Agricultural Science & Technology》 CAS 2011年第10期1449-1452,共4页
[Objective] This paper aims to construct an improved fuzzy decision tree which is based on clustering,and researches into its application in the screening of maize germplasm.[Method] A new decision tree algorithm base... [Objective] This paper aims to construct an improved fuzzy decision tree which is based on clustering,and researches into its application in the screening of maize germplasm.[Method] A new decision tree algorithm based upon clustering is adopted in this paper,which is improved against the defect that traditional decision tree algorithm fails to handle samples of no classes.Meanwhile,the improved algorithm is also applied to the screening of maize varieties.Through the indices as leaf area,plant height,dry weight,potassium(K) utilization and others,maize seeds with strong tolerance of hypokalemic are filtered out.[Result] The algorithm in the screening of maize germplasm has great applicability and good performance.[Conclusion] In the future more efforts should be made to compare improved the performance of fuzzy decision tree based upon clustering with the performance of traditional fuzzy one,and it should be applied into more realistic problems. 展开更多
关键词 FCM decision tree based upon clustering Screening indices Tolerance of hypokalemic
下载PDF
Decision tree support vector machine based on genetic algorithm for multi-class classification 被引量:16
9
作者 Huanhuan Chen Qiang Wang Yi Shen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期322-326,共5页
To solve the multi-class fault diagnosis tasks, decision tree support vector machine (DTSVM), which combines SVM and decision tree using the concept of dichotomy, is proposed. Since the classification performance of... To solve the multi-class fault diagnosis tasks, decision tree support vector machine (DTSVM), which combines SVM and decision tree using the concept of dichotomy, is proposed. Since the classification performance of DTSVM highly depends on its structure, to cluster the multi-classes with maximum distance between the clustering centers of the two sub-classes, genetic algorithm is introduced into the formation of decision tree, so that the most separable classes would be separated at each node of decisions tree. Numerical simulations conducted on three datasets compared with "one-against-all" and "one-against-one" demonstrate the proposed method has better performance and higher generalization ability than the two conventional methods. 展开更多
关键词 support vector machine (SVM) decision tree GENETICALGORITHM classification.
下载PDF
Mapping landslide susceptibility at the Three Gorges Reservoir, China, using gradient boosting decision tree,random forest and information value models 被引量:9
10
作者 CHEN Tao ZHU Li +3 位作者 NIU Rui-qing TRINDER C John PENG Ling LEI Tao 《Journal of Mountain Science》 SCIE CSCD 2020年第3期670-685,共16页
This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting de... This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting decision tree(GBDT), random forest(RF) and information value(InV) models, were used, and the performances were assessed and compared. In total, 202 landslides were mapped by using a series of field surveys, aerial photographs, and reviews of historical and bibliographical data. Nine causative factors were then considered in landslide susceptibility map generation by using the GBDT, RF and InV models. All of the maps of the causative factors were resampled to a resolution of 28.5 m. Of the 486289 pixels in the area,28526 pixels were landslide pixels, and 457763 pixels were non-landslide pixels. Finally, landslide susceptibility maps were generated by using the three machine learning models, and their performances were assessed through receiver operating characteristic(ROC) curves, the sensitivity, specificity,overall accuracy(OA), and kappa coefficient(KAPPA). The results showed that the GBDT, RF and In V models in overall produced reasonable accurate landslide susceptibility maps. Among these three methods, the GBDT method outperforms the other two machine learning methods, which can provide strong technical support for producing landslide susceptibility maps in TGR. 展开更多
关键词 MAPPING LANDSLIDE SUSCEPTIBILITY Gradient BOOSTING decision tree Random FOREST Information value model Three Gorges Reservoir
下载PDF
Nitrogen removal influence factors in A/O process and decision trees for nitrification/denitrification system 被引量:6
11
作者 MAYong PENGYong-zhen +1 位作者 WANGShu-ying WANGXiao-lian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期901-907,共7页
In order to improve nitrogen removal in anoxic/oxic(A/O) process effectively for treating domestic wastewaters, the influence factors, DO(dissolved oxygen), nitrate recirculation, sludge recycle, SRT(solids residence ... In order to improve nitrogen removal in anoxic/oxic(A/O) process effectively for treating domestic wastewaters, the influence factors, DO(dissolved oxygen), nitrate recirculation, sludge recycle, SRT(solids residence time), influent COD/TN and HRT(hydraulic retention time) were studied. Results indicated that it was possible to increase nitrogen removal by using corresponding control strategies, such as, adjusting the DO set point according to effluent ammonia concentration; manipulating nitrate recirculation flow according to nitrate concentration at the end of anoxic zone. Based on the experiments results, a knowledge-based approach for supervision of the nitrogen removal problems was considered, and decision trees for diagnosing nitrification and denitrification problems were built and successfully applied to A/O process. 展开更多
关键词 A/O process NITRIFICATION DENITRIFICATION nitrogen removal decision trees
下载PDF
Assessing the performance of decision tree and neural network models in mapping soil properties 被引量:6
12
作者 Fatemeh HATEFFARD Payam DOLATI +1 位作者 Ahmad HEIDARI Ali Asghar ZOLFAGHARI 《Journal of Mountain Science》 SCIE CSCD 2019年第8期1833-1847,共15页
To build any spatial soil database, a set of environmental data including digital elevation model(DEM) and satellite images beside geomorphic landscape description are essentials. Such a database, integrates field obs... To build any spatial soil database, a set of environmental data including digital elevation model(DEM) and satellite images beside geomorphic landscape description are essentials. Such a database, integrates field observations and laboratory analyses data with the results obtained from qualitative and quantitative models. So far, various techniques have been developed for soil data processing. The performance of Artificial Neural Network(ANN) and Decision Tree(DT) models was compared to map out some soil attributes in Alborz Province, Iran. Terrain attributes derived from a DEM along with Landsat 8 ETM+, geomorphology map, and the routine laboratory analyses of the studied area were used as input data. The relationships between soil properties(including sand, silt, clay, electrical conductivity, organic carbon, and carbonates) and the environmental variables were assessed using the Pearson Correlation Coefficient and Principle Components Analysis. Slope, elevation, geomforms, carbonate index, stream network, wetness index, and the band’s number 2, 3, 4, and 5 were the most significantly correlated variables. ANN and DT did not show the same accuracy in predicting all parameters. The DT model showed higher performances in estimating sand(R^2=0.73), silt(R^2=0.70), clay(R^2=0.72), organic carbon(R^2=0.71), and carbonates(R^2=0.70). While the ANN model only showed higher performance in predicting soil electrical conductivity(R^2=0.95). The results showed that determination the best model to use, is dependent upon the relation between the considered soil properties with the environmental variables. However, the DT model showed more reasonable results than the ANN model in this study. The results showed that before using a certain model to predict variability of all soil parameters, it would be better to evaluate the efficiency of all possible models for choosing the best fitted model for each property. In other words, most of the developed models are sitespecific and may not be applicable to use for predicting other soil properties or other area. 展开更多
关键词 Digital SOIL MAPPING SOIL properties environmental VARIABLES Artificial Neural Network decision tree
下载PDF
Safety validation of decision trees for hepatocellular carcinoma 被引量:4
13
作者 Xian-Qiang Wang Zhe Liu +7 位作者 Wen-Ping Lv Ying Luo Guang-Yun Yang Chong-Hui Li Xiang-Fei Meng Yang Liu Ke-Sen Xu Jia-Hong Dong 《World Journal of Gastroenterology》 SCIE CAS 2015年第31期9394-9402,共9页
AIM: To evaluate a different decision tree for safe liver resection and verify its efficiency.METHODS: A total of 2457 patients underwent hepatic resection between January 2004 and December 2010 at the Chinese PLA Gen... AIM: To evaluate a different decision tree for safe liver resection and verify its efficiency.METHODS: A total of 2457 patients underwent hepatic resection between January 2004 and December 2010 at the Chinese PLA General Hospital,and 634 hepatocellular carcinoma(HCC) patients were eligible for the final analyses. Post-hepatectomy liver failure(PHLF) was identified by the association of prothrombin time < 50% and serum bilirubin > 50 μmol/L(the "50-50" criteria),which were assessed at day 5 postoperatively or later. The Swiss-Clavien decision tree,Tokyo University-Makuuchi decision tree,and Chinese consensus decision tree were adopted to divide patients into two groups based on those decision trees in sequence,and the PHLF rates were recorded.RESULTS: The overall mortality and PHLF rate were 0.16% and 3.0%. A total of 19 patients experienced PHLF. The numbers of patients to whom the SwissClavien,Tokyo University-Makuuchi,and Chinese consensus decision trees were applied were 581,573,and 622,and the PHLF rates were 2.75%,2.62%,and 2.73%,respectively. Significantly more cases satisfied the Chinese consensus decision tree than the Swiss-Clavien decision tree and Tokyo University-Makuuchi decision tree(P < 0.01,P < 0.01); nevertheless,the latter two shared no difference(P = 0.147). The PHLF rate exhibited no significant difference with respect to the three decision trees.CONCLUSION: The Chinese consensus decision tree expands the indications for hepatic resection for HCC patients and does not increase the PHLF rate compared to the Swiss-Clavien and Tokyo UniversityMakuuchi decision trees. It would be a safe and effective algorithm for hepatectomy in patients with hepatocellular carcinoma. 展开更多
关键词 HEPATECTOMY LIVER FAILURE decision tree
下载PDF
Decision tree and deep learning based probabilistic model for character recognition 被引量:6
14
作者 A.K.Sampath Dr.N.Gomathi 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第12期2862-2876,共15页
One of the most important methods that finds usefulness in various applications, such as searching historical manuscripts, forensic search, bank check reading, mail sorting, book and handwritten notes transcription, i... One of the most important methods that finds usefulness in various applications, such as searching historical manuscripts, forensic search, bank check reading, mail sorting, book and handwritten notes transcription, is handwritten character recognition. The common issues in the character recognition are often due to different writing styles, orientation angle, size variation(regarding length and height), etc. This study presents a classification model using a hybrid classifier for the character recognition by combining holoentropy enabled decision tree(HDT) and deep neural network(DNN). In feature extraction, the local gradient features that include histogram oriented gabor feature and grid level feature, and grey level co-occurrence matrix(GLCM) features are extracted. Then, the extracted features are concatenated to encode shape, color, texture, local and statistical information, for the recognition of characters in the image by applying the extracted features to the hybrid classifier. In the experimental analysis, recognition accuracy of 96% is achieved. Thus, it can be suggested that the proposed model intends to provide more accurate character recognition rate compared to that of character recognition techniques used in the literature. 展开更多
关键词 GREY level CO-OCCURRENCE matrix FEATURE HISTOGRAM oriented GABOR gradient FEATURE hybrid CLASSIFIER holoentropy enabled decision tree CLASSIFIER
下载PDF
Landslide susceptibility zonation method based on C5.0 decision tree and K-means cluster algorithms to improve the efficiency of risk management 被引量:18
15
作者 Zizheng Guo Yu Shi +2 位作者 Faming Huang Xuanmei Fan Jinsong Huang 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期243-261,共19页
Machine learning algorithms are an important measure with which to perform landslide susceptibility assessments, but most studies use GIS-based classification methods to conduct susceptibility zonation.This study pres... Machine learning algorithms are an important measure with which to perform landslide susceptibility assessments, but most studies use GIS-based classification methods to conduct susceptibility zonation.This study presents a machine learning approach based on the C5.0 decision tree(DT) model and the K-means cluster algorithm to produce a regional landslide susceptibility map. Yanchang County, a typical landslide-prone area located in northwestern China, was taken as the area of interest to introduce the proposed application procedure. A landslide inventory containing 82 landslides was prepared and subsequently randomly partitioned into two subsets: training data(70% landslide pixels) and validation data(30% landslide pixels). Fourteen landslide influencing factors were considered in the input dataset and were used to calculate the landslide occurrence probability based on the C5.0 decision tree model.Susceptibility zonation was implemented according to the cut-off values calculated by the K-means cluster algorithm. The validation results of the model performance analysis showed that the AUC(area under the receiver operating characteristic(ROC) curve) of the proposed model was the highest, reaching 0.88,compared with traditional models(support vector machine(SVM) = 0.85, Bayesian network(BN) = 0.81,frequency ratio(FR) = 0.75, weight of evidence(WOE) = 0.76). The landslide frequency ratio and frequency density of the high susceptibility zones were 6.76/km^(2) and 0.88/km^(2), respectively, which were much higher than those of the low susceptibility zones. The top 20% interval of landslide occurrence probability contained 89% of the historical landslides but only accounted for 10.3% of the total area.Our results indicate that the distribution of high susceptibility zones was more focused without containing more " stable" pixels. Therefore, the obtained susceptibility map is suitable for application to landslide risk management practices. 展开更多
关键词 Landslide susceptibility Frequency ratio C5.0 decision tree K-means cluster Classification Risk management
下载PDF
Soil Organic Matter Mapping by Decision Tree Modeling 被引量:6
16
作者 ZHOUBin ZHANGXing-Gang WANGFan WANGRen-Chao 《Pedosphere》 SCIE CAS CSCD 2005年第1期103-109,共7页
Based on a case study of Longyou County, Zhejiang Province, the decision tree, a data mining method, was used to analyze the relationships between soil organic matter (SOM) and other environmental and satellite sensin... Based on a case study of Longyou County, Zhejiang Province, the decision tree, a data mining method, was used to analyze the relationships between soil organic matter (SOM) and other environmental and satellite sensing spatial data. The decision tree associated SOM content with some extensive easily observable landscape attributes, such as landform, geology, land use, and remote sensing images, thus transforming the SOM-related information into a clear, quantitative, landscape factor-associated regular syst… 展开更多
关键词 decision tree SOM spatial prediction
下载PDF
Fetal distress prediction using discriminant analysis, decision tree, and artificial neural network 被引量:7
17
作者 Mei-Ling Huang Yung-Yan Hsu 《Journal of Biomedical Science and Engineering》 2012年第9期526-533,共8页
Fetal distress is one of the main factors to cesarean section in obstetrics and gynecology. If the fetus lack of oxygen in uterus, threat to the fetal health and fetal death could happen. Cardiotocography (CTG) is the... Fetal distress is one of the main factors to cesarean section in obstetrics and gynecology. If the fetus lack of oxygen in uterus, threat to the fetal health and fetal death could happen. Cardiotocography (CTG) is the most widely used technique to monitor the fetal health and fetal heart rate (FHR) is an important index to identify occurs of fetal distress. This study is to propose discriminant analysis (DA), decision tree (DT), and artificial neural network (ANN) to evaluate fetal distress. The results show that the accuracies of DA, DT and ANN are 82.1%, 86.36% and 97.78%, respectively. 展开更多
关键词 FETAL DISTRESS CARDIOTOCOGRAPHY (CTG) DISCRIMINANT Analysis decision tree Artificial Neural Network
下载PDF
Canadian children’s and youth’s adherence to the 24-h movement guidelines during the COVID-19 pandemic: A decision tree analysis 被引量:6
18
作者 Michelle D.Guerrero Leigh M.Vanderloo +3 位作者 Ryan E.Rhodes Guy Faulkner Sarah A.Moore Mark S.Tremblay 《Journal of Sport and Health Science》 SCIE 2020年第4期313-321,共9页
Purpose:The purpose of this study was to use decision tree modeling to generate profiles of children and youth who were more and less likely to meet the Canadian 24-h movement guidelines during the coronavirus disease... Purpose:The purpose of this study was to use decision tree modeling to generate profiles of children and youth who were more and less likely to meet the Canadian 24-h movement guidelines during the coronavirus disease-2019(COVID-19)outbreak.Methods:Data for this study were from a nationally representative sample of 1472 Canadian parents(Meanage=45.12,SD=7.55)of children(511 years old)or youth(1217 years old).Data were collected in April 2020 via an online survey.Survey items assessed demographic,behavioral,social,micro-environmental,and macro-environmental characteristics.Four decision trees of adherence and non-adherence to all movement recommendations combined and each individual movement recommendation(physical activity(PA),screen time,and sleep)were generated.Results:Results revealed specific combinations of adherence and non-adherence characteristics.Characteristics associated with adherence to the recommendation(s)included high parental perceived capability to restrict screen time,annual household income ofCAD 100,000,increases in children’s and youth’s outdoor PA/sport since the COVID-19 outbreak began,being a boy,having parents younger than 43 years old,and small increases in children’s and youth’s sleep duration since the COVID-19 outbreak began.Characteristics associated with non-adherence to the recommendation(s)included low parental perceived capability to restrict screen time,youth aged 1217 years,decreases in children’s and youth’s outdoor PA/sport since the COVID-19 outbreak began,primary residences located in all provinces except Quebec,low parental perceived capability to support children’s and youth’s sleep and PA,and annual household income ofCAD 99,999.Conclusion:Our results show that specific characteristics interact to contribute to(non)adherence to the movement behavior recommendations.Results highlight the importance of targeting parents’perceived capability for the promotion of children’s and youth’s movement behaviors during challenging times of the COVID-19 pandemic,paying particular attention to enhancing parental perceived capability to restrict screen time. 展开更多
关键词 decision tree analysis Parental perceived capability Physical activity Screen time Sleep
下载PDF
Travel time prediction model of freeway based on gradient boosting decision tree 被引量:7
19
作者 Cheng Juan Chen Xianhua 《Journal of Southeast University(English Edition)》 EI CAS 2019年第3期393-398,共6页
To investigate the travel time prediction method of the freeway, a model based on the gradient boosting decision tree (GBDT) is proposed. Eleven variables (namely, travel time in current period T i , traffic flow in c... To investigate the travel time prediction method of the freeway, a model based on the gradient boosting decision tree (GBDT) is proposed. Eleven variables (namely, travel time in current period T i , traffic flow in current period Q i , speed in current period V i , density in current period K i , the number of vehicles in current period N i , occupancy in current period R i , traffic state parameter in current period X i , travel time in previous time period T i -1 , etc.) are selected to predict the travel time for 10 min ahead in the proposed model. Data obtained from VISSIM simulation is used to train and test the model. The results demonstrate that the prediction error of the GBDT model is smaller than those of the back propagation (BP) neural network model and the support vector machine (SVM) model. Travel time in current period T i is the most important variable among all variables in the GBDT model. The GBDT model can produce more accurate prediction results and mine the hidden nonlinear relationships deeply between variables and the predicted travel time. 展开更多
关键词 gradient boosting decision tree (GBDT) travel time prediction FREEWAY traffic state parameter
下载PDF
FPGA-Based Network Traffic Security: Design and Implementation Using C5.0 Decision Tree Classifier 被引量:2
20
作者 Tarek Salah Sobh Mohamed Ibrahiem Amer 《Journal of Electronic Science and Technology》 CAS 2013年第4期393-403,共11页
In this work, a hardware intrusion detection system (IDS) model and its implementation are introduced to perform online real-time traffic monitoring and analysis. The introduced system gathers some advantages of man... In this work, a hardware intrusion detection system (IDS) model and its implementation are introduced to perform online real-time traffic monitoring and analysis. The introduced system gathers some advantages of many IDSs: hardware based from implementation point of view, network based from system type point of view, and anomaly detection from detection approach point of view. In addition, it can detect most of network attacks, such as denial of services (DOS), leakage, etc. from detection behavior point of view and can detect both internal and external intruders from intruder type point of view. Gathering these features in one IDS system gives lots of strengths and advantages of the work. The system is implemented by using field programmable gate array (FPGA), giving a more advantages to the system. A C5.0 decision tree classifier is used as inference engine to the system and gives a high detection ratio of 99.93%. 展开更多
关键词 C5.0 decision tree field programm-able gate array network monitoring network security.
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部