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GPT2-ICC:A data-driven approach for accurate ion channel identification using pre-trained large language models 被引量:1
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作者 Zihan Zhou Yang Yu +9 位作者 Chengji Yang Leyan Cao Shaoying Zhang Junnan Li Yingnan Zhang Huayun Han Guoliang Shi Qiansen Zhang Juwen Shen Huaiyu Yang 《Journal of Pharmaceutical Analysis》 2025年第8期1800-1809,共10页
Current experimental and computational methods have limitations in accurately and efficiently classifying ion channels within vast protein spaces.Here we have developed a deep learning algorithm,GPT2 Ion Channel Class... Current experimental and computational methods have limitations in accurately and efficiently classifying ion channels within vast protein spaces.Here we have developed a deep learning algorithm,GPT2 Ion Channel Classifier(GPT2-ICC),which effectively distinguishing ion channels from a test set containing approximately 239 times more non-ion-channel proteins.GPT2-ICC integrates representation learning with a large language model(LLM)-based classifier,enabling highly accurate identification of potential ion channels.Several potential ion channels were predicated from the unannotated human proteome,further demonstrating GPT2-ICC’s generalization ability.This study marks a significant advancement in artificial-intelligence-driven ion channel research,highlighting the adaptability and effectiveness of combining representation learning with LLMs to address the challenges of imbalanced protein sequence data.Moreover,it provides a valuable computational tool for uncovering previously uncharacterized ion channels. 展开更多
关键词 Ion channel Artificial intelligence Representation learning GPT2 Protein language model
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Comparison of the pathogenicity of multiple SARS-CoV-2 variants in mouse models
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作者 Qi Lv Ming Liu +10 位作者 Feifei Qi Mingya Liu Fengdi Li Ran Deng Xujian Liang Yanfeng Xu Zhiqi Song Yiwei Yan Shuyue Li Guocui Mou Linlin Bao 《Animal Models and Experimental Medicine》 2025年第7期1302-1312,共11页
Background:New variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to drive global epidemics and pose significant health risks.The pathogenicity of these variants evolves under immune press... Background:New variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to drive global epidemics and pose significant health risks.The pathogenicity of these variants evolves under immune pressure and host factors.Understanding these changes is crucial for epidemic control and variant research.Methods:Human angiotensin-converting enzyme 2(hACE2)transgenic mice were in-tranasally challenged with the original strain WH-09 and the variants Delta,Beta,and Omicron BA.1,while BALB/c mice were challenged with Omicron subvariants BA.5,BF.7,and XBB.1.To compare the pathogenicity differences among variants,we con-ducted a comprehensive analysis that included clinical symptom observation,meas-urement of viral loads in the trachea and lungs,evaluation of pulmonary pathology,analysis of immune cell infiltration,and quantification of cytokine levels.Results:In hACE2 mice,the Beta variant caused significant weight loss,severe lung inflammation,increased inflammatory and chemotactic factor secretion,greater mac-rophage and neutrophil infiltration in the lungs,and higher viral loads with prolonged shedding duration.In contrast,BA.1 showed a significant reduction in pathogenicity.The BA.5,BF.7,and XBB.1 variants were less pathogenic than the WH-09,Beta,and Delta variants when infected in BALB/c mice.This was evidenced by reduced weight loss,diminished pulmonary pathology,decreased secretion of inflammatory factors and chemokines,reduced macrophage and neutrophil infiltration,as well as lower viral loads in both the trachea and lungs.Conclusion:In hACE2 mice,the Omicron variant demonstrated the lowest pathogenic-ity,while the Beta variant exhibited the highest.Pathogenicity of the Delta variant was comparable to the original WH-09 strain.Among BALB/c mice,Omicron subvari-ants BA.5,BF.7,and XBB.1 showed no statistically significant differences in virulence. 展开更多
关键词 mice model PATHOGENICITY SARS-CoV-2 VARIANTS
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Comparison on Winter Wheat Yield Estimating Models Based on Radarsat-2 and HJ Satellite in Huaihe River Region 被引量:1
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作者 范伟 陈磊 +2 位作者 陈娟 闫洪凯 刘韬 《Agricultural Science & Technology》 CAS 2016年第4期1019-1023,共5页
The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model... The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model. With Shou County and Huaiyuan County of Anhui Province as the experimental fields of winter wheat producing areas, the linear winter wheat yield estimating models were established by adopting backscattering coefficient and Normalized Difference Vegetation Index(NDVI) based on images from the synthetic aperture radar(SAR)—RDARSAT-2 and HJ satellite photographed in mid-April and early May, 2014, and then comparisons were conducted on the accuracy of the yield estimating models. The accuracies of the yield estimating models established using co-polarized(HH) and cross-polarized(HV) modes of SAR in Jiangou Town, Shou County were 68.37% and 74.01%, respectively, while the accuracies in Longkang Town, Huaiyuan County were 63.10%and 69.10%, respectively. Accuracies of yield estimating models established by HJ satellite data were 69.52% and 66.43% in Shou County and Huaiyuan County, respectively. Accuracies of winter yield estimating model based on HJ satellite data and that based on SAR were closed, and the yield difference of winter wheat in the lodging region was analyzed in detail. The model results laid the foundation and accumulated experience for the verification, parameters correction and promotion of the winter wheat yield estimating model. 展开更多
关键词 Winter wheat yield estimating model Synthetic aperture radar RADARSAT-2 HJ satellite model comparison
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基于24Model的动火作业事故致因文本挖掘 被引量:1
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作者 牛茂辉 李威君 +1 位作者 刘音 王璐 《中国安全科学学报》 北大核心 2025年第3期151-158,共8页
为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告... 为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告数据集,构建分类模型;然后,通过基于BERT的关键字提取算法(KeyBERT)和词频-逆文档频率(TF-IDF)算法的组合权重,结合24Model框架,建立动火作业事故文本关键词指标体系;最后,通过文本挖掘关键词之间的网络共现关系,分析得到事故致因之间的相互关联。结果显示,基于BERT的24Model分类器模型能够系统准确地判定动火作业事故致因类别,通过组合权重筛选得到4个层级关键词指标体系,其中安全管理体系的权重最大,结合共现网络分析得到动火作业事故的7项关键致因。 展开更多
关键词 2-4”模型(24model) 动火作业 事故致因 文本挖掘 指标体系
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二氧化碳地质封存盖层力学建模及其封闭性研究——以辽河油田CCUS试验区S229块为例
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作者 施玉华 梁飞 +2 位作者 田梅 张雪涛 蒋星达 《石油物探》 北大核心 2026年第1期182-194,共13页
碳捕集、利用与封存(carbon capture,utilization and storage,CCUS)在应对全球气候变化、减少温室气体排放方面具有重要意义。二氧化碳(CO_(2))地质封存是一个动态过程,极易引起地质体应力场改变,诱发盖层岩石力学破坏,造成CO_(2)泄露... 碳捕集、利用与封存(carbon capture,utilization and storage,CCUS)在应对全球气候变化、减少温室气体排放方面具有重要意义。二氧化碳(CO_(2))地质封存是一个动态过程,极易引起地质体应力场改变,诱发盖层岩石力学破坏,造成CO_(2)泄露。因此,盖层封闭性研究是CCUS项目实施中的关键研究内容之一。以辽河油田CCUS试验区S229区块为例,针对二氧化碳地质封存过程中盖层封闭性评价需求,基于地质、测井及岩心实验数据,采用三维地质力学建模技术,结合毛细管压力理论和摩尔-库伦破坏准则,计算盖层最大CO_(2)羽流柱高度,并分析盖层张性破坏压力与剪切破坏压力。提取注入井点位置的破坏压力阈值,实现盖层封闭性定点定量评价,明确研究区块CO_(2)注入井极限压力。分析表明,研究区盖层泥岩毛细管封闭能力较好,所能封闭的最大CO_(2)羽流柱高度为379.08 m;盖层张性破裂压力范围为58.3~62.1 MPa,剪切破裂压力范围为54.8~60.9 MPa;井36-70附近盖层剪切破坏风险最高,极限井底压力为58.09 MPa。研究结果表明,S229区块盖层具备较好的封闭性能,但需严格控制CO_(2)注入压力以避免力学破坏。研究成果为研究区CCUS项目注入参数优化及安全实施提供了指导。 展开更多
关键词 CCUS 地质力学建模 盖层封闭评价 CO_(2)羽流柱高度 破坏压力
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COX-2 in liver,from regeneration to hepatocarcinogenesis:What we have learned from animal models? 被引量:12
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作者 Paloma Martín-Sanz Rafael Mayoral +1 位作者 Marta Casado Lisardo Boscá 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第12期1430-1435,共6页
The use of animals lacking genes or expressing genes under the control of cell-specific promoters has signifi cantly increased our knowledge of the genetic and molecular basis of physiopathology,allowing testing of fu... The use of animals lacking genes or expressing genes under the control of cell-specific promoters has signifi cantly increased our knowledge of the genetic and molecular basis of physiopathology,allowing testing of functional hypotheses and validation of biochemical and pharmacologic approaches in order to understand cell function.However,with unexpected frequency,gene knockout animals and,more commonly,animal models of transgenesis give experimental support to even opposite conclusions on gene function.Here we summarize what we learned on the role of cyclooxygenase 2(COX-2) in liver and revise the results obtained in 3 independent models of mice expressing a COX-2 transgene specifi cally in the hepatocyte.Upon challenge with pro-inflammatory stimuli,the animals behave very differently,some transgenic models having a protective effect but others enhancing the injury.In addition,one transgene exerts differential effects on normal liver physiology depending on the transgenic animal model used. 展开更多
关键词 Cyclooxygenase 2 PROSTAGLANDINS Liver diseases Apoptosis Inflammation Animal models
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Comparative study of HFACS and the 24Model accident causation models 被引量:7
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作者 Gui Fu Jia-Lin Cao +1 位作者 Lin Zhou Yuan-Chi Xiang 《Petroleum Science》 SCIE CAS CSCD 2017年第3期570-578,共9页
A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system(HFACS) and the accident causation "2-4" model(2... A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system(HFACS) and the accident causation "2-4" model(24 Model), as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents. 展开更多
关键词 HFACS Accident causation 2-4" model Comparative study Unsafe acts External causes Coaland gas outburst accident
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A Variable Separation Approach to Solve the Integrable and Nonintegrable Models:Coherent Structures of the (2 + 1)-Dimensional KdV Eqnation 被引量:8
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作者 TANG Xiao-Yan LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第7期1-8,共8页
We study the localized coherent structures ofa generally nonintegrable (2+ 1 )-dimensional KdV equation via a variable separation approach. In a special integrable case, the entrance of some arbitrary functions leads ... We study the localized coherent structures ofa generally nonintegrable (2+ 1 )-dimensional KdV equation via a variable separation approach. In a special integrable case, the entrance of some arbitrary functions leads to abundant coherent structures. However, in the general nonintegrable case, an additional condition has to be introduced for these arbitrary functions. Although the additional condition has been introduced into the solutions of the nonintegrable KdV equation, there still exist many interesting solitary wave structures. Especially, the nonintegrable KdV equation possesses the breather-like localized excitations, and the similar static ring soliton solutions as in the integrable case. Furthermor,in the integrable case, the interaction between two travelling ring solitons is elastic, while in the nonintegrable case we cannot find even the single travelling ring soliton solution. 展开更多
关键词 variable SEPARATION approach INTEGRABLE and nonintegrable models (2+1)-dimensional SOLITONS
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Strong ground motion simulation for the 2013 Lushan M_W6.6 earthquake, Sichuan, China, based on the inverted and synthetic slip models 被引量:1
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作者 Wenhao Shen Qiu Zhong Baoping Shi 《Earthquake Science》 2014年第4期377-389,共13页
It is well known that quantitative estimation of slip distributions on fault plane is one of the most important issues for earthquake source inversion related to the fault rupture process. The characteristics of slip ... It is well known that quantitative estimation of slip distributions on fault plane is one of the most important issues for earthquake source inversion related to the fault rupture process. The characteristics of slip distribution on the main fault play a fundamental role to control strong ground motion pattern. A large amount of works have also suggested that variable slip models inverted from longer period ground motion recordings are relevant for the prediction of higher frequency ground motions. Zhang et al. (Chin J Geophys 56:1412-1417, 2013) and Wang et al. (Chin J Geophys 56:1408-1411,2013) published their source inversions for the fault rupturing process soon after the April 20, 2013 Lushan earthquake in Sichuan, China. In this study, first, we synthesize two forward source slip models: the value of maximum slip, fault dimension, size, and dimension of major asperities, and comer wave number obtained from Wang's model is adopted to constrain the gen- eration of k-2 model and crack model. Next, both inverted and synthetic slip models are employed to simulate the ground motions for the Lushan earthquake based on the stochastic finite-fault method. In addition, for a comparison purpose, a stochastic slip model and another k-2 model (k 2 model II) with 2 times value of comer wave number of the original k-2 model (k 2 model I) are also employed for simulation for Lushan event. The simulated results characterized by Modified Mer- calli Intensity (MMI) show that the source slip models based on the inverted and synthetic slip distributions could capture many basic features associated with the ground motion patterns. Moreover, the simulated MMI distributions reflect the rupture directivity effect and the influence of the shallow velocity structure well. On the other hand, the simulated MMI bystochastic slip model and k 2 model II is apparently higher than observed intensity. By contrast, our simulation results show that the higher frequency ground motion is sensitive to the degree of slip roughness; therefore, we suggest that, for realistic ground- motion simulations due to future earthquake, it is imperative to properly estimate the slip roughness distribution. 展开更多
关键词 Stochastic finite-fault model Strong groundmotion -2013 Lushan Mw6.6 earthquake Corner wavenumber k -2 model Crack model
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Establishment of models to predict factors influencing periodontitis in patients with type 2 diabetes mellitus 被引量:3
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作者 Hong-Miao Xu Xuan-Jiang Shen Jia Liu 《World Journal of Diabetes》 SCIE 2023年第12期1793-1802,共10页
BACKGROUND Type 2 diabetes mellitus(T2DM)is associated with periodontitis.Currently,there are few studies proposing predictive models for periodontitis in patients with T2DM.AIM To determine the factors influencing pe... BACKGROUND Type 2 diabetes mellitus(T2DM)is associated with periodontitis.Currently,there are few studies proposing predictive models for periodontitis in patients with T2DM.AIM To determine the factors influencing periodontitis in patients with T2DM by constructing logistic regression and random forest models.METHODS In this a retrospective study,300 patients with T2DM who were hospitalized at the First People’s Hospital of Wenling from January 2022 to June 2022 were selected for inclusion,and their data were collected from hospital records.We used logistic regression to analyze factors associated with periodontitis in patients with T2DM,and random forest and logistic regression prediction models were established.The prediction efficiency of the models was compared using the area under the receiver operating characteristic curve(AUC).RESULTS Of 300 patients with T2DM,224 had periodontitis,with an incidence of 74.67%.Logistic regression analysis showed that age[odds ratio(OR)=1.047,95%confidence interval(CI):1.017-1.078],teeth brushing frequency(OR=4.303,95%CI:2.154-8.599),education level(OR=0.528,95%CI:0.348-0.800),glycosylated hemoglobin(HbA1c)(OR=2.545,95%CI:1.770-3.661),total cholesterol(TC)(OR=2.872,95%CI:1.725-4.781),and triglyceride(TG)(OR=3.306,95%CI:1.019-10.723)influenced the occurrence of periodontitis(P<0.05).The random forest model showed that the most influential variable was HbA1c followed by age,TC,TG, education level, brushing frequency, and sex. Comparison of the prediction effects of the two models showedthat in the training dataset, the AUC of the random forest model was higher than that of the logistic regressionmodel (AUC = 1.000 vs AUC = 0.851;P < 0.05). In the validation dataset, there was no significant difference in AUCbetween the random forest and logistic regression models (AUC = 0.946 vs AUC = 0.915;P > 0.05).CONCLUSION Both random forest and logistic regression models have good predictive value and can accurately predict the riskof periodontitis in patients with T2DM. 展开更多
关键词 Type 2 diabetes mellitus PERIODONTITIS Logistic regression Prediction model Random forest model Gingival disease
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Integrating VGI and 2D hydraulic models into a data assimilation framework for real time flood forecasting and mapping 被引量:3
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作者 Antonio Annis Fernando Nardi 《Geo-Spatial Information Science》 SCIE CSCD 2019年第4期223-236,I0001,共15页
Crowdsourced data can effectively observe environmental and urban ecosystem processes.The use of data produced by untrained people into flood forecasting models may effectively allow Early Warning Systems(EWS)to bette... Crowdsourced data can effectively observe environmental and urban ecosystem processes.The use of data produced by untrained people into flood forecasting models may effectively allow Early Warning Systems(EWS)to better perform while support decision-making to reduce the fatalities and economic losses due to inundation hazard.In this work,we develop a Data Assimilation(DA)method integrating Volunteered Geographic Information(VGI)and a 2D hydraulic model and we test its performances.The proposed framework seeks to extend the capabilities and performances of standard DA works,based on the use of traditional in situ sensors,by assimilating VGI while managing and taking into account the uncertainties related to the quality,and the location and timing of the entire set of observational data.The November 2012 flood in the Italian Tiber River basin was selected as the case study.Results show improvements of the model in terms of uncertainty with a significant persistence of the model updating after the integration of the VGI,even in the case of use of few-selected observations gathered from social media.This will encourage further research in the use of VGI for EWS considering the exponential increase of quality and quantity of smartphone and social media user worldwide. 展开更多
关键词 Crowdsourced data VGI data assimilation(DA) flood forecasting 2D hydraulic modelling
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Influence of formation heterogeneity on foam flooding performance using 2D and 3D models:an experimental study 被引量:3
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作者 Ling-Zhi Hu Lin Sun +2 位作者 Jin-Zhou Zhao Peng Wei Wan-Fen Pu 《Petroleum Science》 SCIE CAS CSCD 2020年第3期734-748,共15页
The formation heterogeneity is considered as one of the major factors limiting the application of foam flooding.In this paper,influences of formation properties,such as permeability,permeability distribution,interlaye... The formation heterogeneity is considered as one of the major factors limiting the application of foam flooding.In this paper,influences of formation properties,such as permeability,permeability distribution,interlayer,sedimentary rhythm and 3D heterogeneity,on the mobility control capability and oil displacement efficiency of foam flooding,were systematically investigated using 2D homogeneous and 2D/3D heterogeneous models under 120°C and salinity of 20×10~4 mg/L.The flow resistance of foam was promoted as the permeability increased,which thus resulted in a considerable oil recovery behavior.In the scenario of the vertical heterogeneous formations,it was observed that the permeability of the high-permeable layer was crucial to foam mobility control,and the positive rhythm appeared favorable to improve the foam flooding performance.The additional oil recovery increased to about 40%.The interlayer was favorable for the increases in mobility reduction factor and oil recovery of foam flooding when the low permeability ratio was involved.For the 3D heterogeneous formations,foam could efficiently adjust the areal and vertical heterogeneity through mobility control and gravity segregation,and thus enhancing the oil recovery to 11%–14%.The results derived from this work may provide some insight for the field test designs of foam flooding. 展开更多
关键词 Foam flooding Permeability ratio 2D/3D models HETEROGENEITY Enhanced oil recovery
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High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model
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作者 Xuefeng Bai Yi Li +3 位作者 Yabo Xie Qiancheng Chen Xin Zhang Jian-Rong Li 《Green Energy & Environment》 SCIE EI CAS 2025年第1期132-138,共7页
The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design platform.High-throughput screening of catalytic performance is feasible since the large MOF str... The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design platform.High-throughput screening of catalytic performance is feasible since the large MOF structure database is available.In this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition reaction.The descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification criterion.The feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were discovered.Among them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction. 展开更多
关键词 Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition
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Mouse models of porcine circovirus 2 infection 被引量:1
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作者 Ting Ouyang Xiao-hui Liu +1 位作者 Hong-sheng Ouyang Lin-zhu Ren 《Animal Models and Experimental Medicine》 2018年第1期23-28,共6页
PCV2 is considered the main pathogen of porcine circovirus diseases and porcine circovirus-associated diseases(PCVD/PCVAD). However, the exact mechanism underlying PCVD/PCVAD is currently unknown. Mouse models of PCV2... PCV2 is considered the main pathogen of porcine circovirus diseases and porcine circovirus-associated diseases(PCVD/PCVAD). However, the exact mechanism underlying PCVD/PCVAD is currently unknown. Mouse models of PCV2 are valuable experimental tools that can shed light on the pathogenesis of infection and will enable the evaluation of antiviral agents and vaccine candidates. In this review, we discuss the current state of knowledge of mouse models used in PCV2 research that has been performed to date, highlighting their strengths and limitations, as well as prospects for future PCV2 studies. 展开更多
关键词 ANIMAL model mouse(Mus musculus) PORCINE CIRCOVIRUS 2(PCV2)
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基于24Model与RF算法的冰雪天气高速公路交通事故影响因素研究
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作者 王俊诚 解学才 孙世梅 《安全》 2025年第11期55-60,共6页
为提升冰雪天气下高速公路的行车安全水平,本文融合事故致因“2-4”模型(24Model)与机器学习方法,构建事故严重程度预测模型并识别关键致因因素。首先,以全国109起冰雪天气高速公路交通事故为样本,基于24Model系统提取15项影响因素,构... 为提升冰雪天气下高速公路的行车安全水平,本文融合事故致因“2-4”模型(24Model)与机器学习方法,构建事故严重程度预测模型并识别关键致因因素。首先,以全国109起冰雪天气高速公路交通事故为样本,基于24Model系统提取15项影响因素,构建适用于机器学习的数据集;然后,对比随机森林(RF)、K近邻与BP神经网络,建立预测模型,并对最优者实施超参数搜索与交叉验证;最后,结合重要度分析,识别影响事故严重程度的关键因素。结果表明:RF模型准确率达到0.8182,且性能最稳定;组织文化缺失为首要致因,驾驶员安全意识不足、低能见度不良天气条件及大型车辆混入亦显著加剧事故严重性。可从优化低能见度路段交通标志与照明设施、完善安全管理体系等方面提出针对性改进对策,为冰雪天气高速公路安全治理提供理论依据与管理参考。 展开更多
关键词 冰雪天气 事故致因“2-4”模型(24model) 事故严重程度 随机森林算法(RF)
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Modelling of Turbulent Nonpremixed CH4/H2 Flame Using Second-Moment Turbulence Closure Models 被引量:1
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作者 李国岫 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期1-8,共8页
Turbulent nonpremixed CH4/H2 flame has been simulated using several typical differential secondmoment turbulence closure (SMTC) models. To clarify the applicability of the various models, the LRR-IP model,JM model, SS... Turbulent nonpremixed CH4/H2 flame has been simulated using several typical differential secondmoment turbulence closure (SMTC) models. To clarify the applicability of the various models, the LRR-IP model,JM model, SSG model as well as two modified LRR-IP models were tested. Some of above-mentioned SMTC models cannot provide the overall satisfactory predictions of this challenging case. It is confirmed again that the standard LRR-IP model considerably overpredict the centerline velocity decay rate, and therefore performs not well. Also it is interesting to observe that the JM model does not perform well in this challenging test case, although it has already been proved successful in other cases. The SSG model produces quite satisfactory prediction and performs equally well or better than the two modified LRR-IP models in the reacting case. It can be concluded that the modified LRR-IP models as well as the SSG model are superior to the other SMTC models in the turbulent nonpremixed CH4/H2 flame. 展开更多
关键词 modelLING nonpremixed CH_4/H_2 flame second-moment turbulence closure
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Global air-sea CO_(2) exchange fl ux since 1980s: results from CMIP6 Earth System Models 被引量:1
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作者 Baoxiao QU Jinming SONG +3 位作者 Xuegang LI Huamao YUAN Kun ZHANG Suqing XU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第4期1417-1436,共20页
The ocean could profoundly modulate the ever-increasing atmospheric CO_(2) by air-sea CO_(2) exchange process,which is also able to cause signifi cant changes of physical and biogeochemical properties in return.In thi... The ocean could profoundly modulate the ever-increasing atmospheric CO_(2) by air-sea CO_(2) exchange process,which is also able to cause signifi cant changes of physical and biogeochemical properties in return.In this study,we assessed the long-term average and spatial-temporal variability of global air-sea CO_(2) exchange fl ux(F CO_(2))since 1980s basing on the results of 18 Coupled Model Intercomparison Project Phase 6(CMIP6)Earth System Models(ESMs).Our fi ndings indicate that the CMIP6 ESMs simulated global CO_(2) sink in recent three decades ranges from 1.80 to 2.24 Pg C/a,which is coincidence with the results of cotemporaneous observations.What’s more,the CMIP6 ESMs consistently show that the global oceanic CO_(2) sink has gradually intensifi ed since 1980s as well as the observations.This study confi rms the simulated F CO_(2) could reach agreements with the observations in the aspect of primary climatological characteristics,however,the simulation skills of CIMP6 ESMs in diverse open-sea biomes are unevenness.None of the 18 CMIP6 ESMs could reproduce the observed F CO_(2) increasement in the central-eastern tropical Pacifi c and the midlatitude Southern Ocean.Defi ciencies of some CMIP6 ESMs in reproducing the atmospheric pressure systems of the Southern Hemisphere and the El Niño-Southern Oscillation(ENSO)mode of the tropical Pacifi c are probably the major causes. 展开更多
关键词 air-sea CO_(2)fl ux Coupled model Intercomparison Project Phase 6(CMIP6) Earth System model(ESM) long-term average spatial-temporal variability
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Spatial Inhomogeneity of Atmospheric CO_(2) Concentration and Its Uncertainty in CMIP6 Earth System Models 被引量:1
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作者 Chengjun XIE Tongwen WU +7 位作者 Jie ZHANG Kalli FURTADO Yumeng ZHOU Yanwu ZHANG Fanghua WU Weihua JIE He ZHAO Mengzhe ZHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第11期2108-2126,共19页
This paper provides a systematic evaluation of the ability of 12 Earth System Models(ESMs)participating in the Coupled Model Intercomparison Project Phase 6(CMIP6)to simulate the spatial inhomogeneity of the atmospher... This paper provides a systematic evaluation of the ability of 12 Earth System Models(ESMs)participating in the Coupled Model Intercomparison Project Phase 6(CMIP6)to simulate the spatial inhomogeneity of the atmospheric carbon dioxide(CO_(2))concentration.The multi-model ensemble mean(MME)can reasonably simulate the increasing trend of CO_(2) concentration from 1850 to 2014,compared with the observation data from the Scripps CO_(2) Program and CMIP6 prescribed data,and improves upon the CMIP5 MME CO_(2) concentration(which is overestimated after 1950).The growth rate of CO_(2) concentration in the northern hemisphere(NH)is higher than that in the southern hemisphere(SH),with the highest growth rate in the mid-latitudes of the NH.The MME can also reasonably simulate the seasonal amplitude of CO_(2) concentration,which is larger in the NH than in the SH and grows in amplitude after the 1950s(especially in the NH).Although the results of the MME are reasonable,there is a large spread among ESMs,and the difference between the ESMs increases with time.The MME results show that regions with relatively large CO_(2) concentrations(such as northern Russia,eastern China,Southeast Asia,the eastern United States,northern South America,and southern Africa)have greater seasonal variability and also exhibit a larger inter-model spread.Compared with CMIP5,the CMIP6 MME simulates an average spatial distribution of CO_(2) concentration that is much closer to the site observations,but the CMIP6-inter-model spread is larger.The inter-model differences of the annual means and seasonal cycles of atmospheric CO_(2) concentration are both attributed to the differences in natural sources and sinks of CO_(2) between the simulations. 展开更多
关键词 CMIP6 Earth System models the simulation of atmospheric CO_(2)concentration spatial inhomogeneity UNCERTAINTY
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Animal models for SARS-CoV-2 and SARS-CoV-1 pathogenesis,transmission and therapeutic evaluation 被引量:3
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作者 Udhaya Bharathy Saravanan Mayurikaa Namachivayam +2 位作者 Rajesh Jeewon Jian-Dong Huang Siva Sundara Kumar Durairajan 《World Journal of Virology》 2022年第1期40-56,共17页
There is a critical need to develop animal models to alleviate vaccine and drug development difficulties against zoonotic viral infections.The coronavirus family,which includes severe acute respiratory syndrome corona... There is a critical need to develop animal models to alleviate vaccine and drug development difficulties against zoonotic viral infections.The coronavirus family,which includes severe acute respiratory syndrome coronavirus 1 and severe acute respiratory syndrome coronavirus 2,crossed the species barrier and infected humans,causing a global outbreak in the 21st century.Because humans do not have pre-existing immunity against these viral infections and with ethics governing clinical trials,animal models are therefore being used in clinical studies to facilitate drug discovery and testing efficacy of vaccines.The ideal animal models should reflect the viral replication,clinical signs,and pathological responses observed in humans.Different animal species should be tested to establish an appropriate animal model to study the disease pathology,transmission and evaluation of novel vaccine and drug candidates to treat coronavirus disease 2019.In this context,the present review summarizes the recent progress in developing animal models for these two pathogenic viruses and highlights the utility of these models in studying SARS-associated coronavirus diseases. 展开更多
关键词 Animal models SARS-CoV-1 SARS-CoV-2 COVID-19 Mice HAMSTER Non-human primates PATHOGENESIS TRANSMISSION Therapeutics
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How the Information and Communications Technology Threaten Our Privacy: The Case of Email and P2P Propagation Models 被引量:1
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作者 Han-Wei Hsiao Cathy S. Lin Kun-Yu Chert 《Computer Technology and Application》 2011年第10期765-773,共9页
With the rapid growth of information and communication technology (ICT), the violation of information privacy has increased in recent years. The privacy concerns now re-emerge right because people perceives a threat... With the rapid growth of information and communication technology (ICT), the violation of information privacy has increased in recent years. The privacy concerns now re-emerge right because people perceives a threat from new ICT that are equipped with enhanced capabilities for surveillance, storage, retrieval, and diffusion of personal information. With the trend in the prevalence and the easy use of ICT, it is of necessary to pay much attention to the issue how the ICT can threaten the privacy of individuals on the Internet. While the Email and P2P (Peer-to-Peer) tools are the most popular ICT, this paper aims at understanding their respectively dissemination patterns in spreading of personal private information. To this purpose, this paper using dynamic model technique to simulate the pattern of sensitive or personal private information propagating situation. In this study, an Email propagation model and a Susceptible-lnfected-Removed (SIR) model are proposed to simulate the propagation patterns of Email and P2P network respectively. Knowing their dissemination patterns would be helpful for system designers, ICT manager, corporate IT personnel, educators, policy makers, and legislators to incorporate consciousness of social and ethical information issues into the protection of information privacy. 展开更多
关键词 Information privacy propagation model EMAIL peer-to-peer (P2P)
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