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Comparison of LR,5-CV SVM,GA SVM,and PSO SVM for landslide susceptibility assessment in Tibetan Plateau area,China

Journal of Mountain Science 2023年第4期20卷 979-995页

作者： ZHANG Ying-bin XU Pei-yi LIU Jing he Jian-xian YANG Hao-tian ZENG Ying he yun-yong YANG Chang-feng Department of Geotechnical Engineering School of Civil EngineeringSouthwest Jiaotong UniversityChengdu610031China Sichuan Highway Planning SurveyDesign and Research Institute Ltd.Chengdu610041China

The applicability of statistics-based landslide susceptibility assessment methods is affected by the number of historical *** studies have proposed support vector machine(SVM)as a small-sample learning ***,those studies demonstrated that different parameters can affect model *** optimized the SVM and obtained models as 5-fold cross validation(5-CV)SVM,genetic algorithm(GA)SVM,and particle swarm optimization(PSO)*** study compared the prediction performances of logistic regression(LR),5-CV SVM,GA SVM,and PSO SVM on landslide susceptibility mapping,to explore the spatial distribution of landslide susceptibility in the study area in Tibetan Plateau,China.A geospatial database was established based on 392 historical landslides and 392 non-landslides in the study *** used 11 influencing factors of altitude,slope,aspect,curvature,lithology,normalized difference vegetation index(NDVI),distance to road,distance to river,distance to fault,peak ground acceleration(PGA),and rainfall to construct an influencing factor evaluation *** evaluate the models,four susceptibility maps were compared via receiver operating characteristics(ROC)curve and the results showed that prediction rates for the models are 84%(LR),87%(5-CV SVM),85%(GA SVM),and 90%(PSO SVM).We also used precision,recall,F1-score and accuracy to assess the quality performance of these *** results showed that the PSO SVM had greater potential for future implementation in the Tibetan Plateau area because of its superior performance in the landslide susceptibility assessment.

关键词： Tibetan Plateau area Logistic regression Support vector machine Landslide susceptibility assessment

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Assessment of earthquake-induced landslide hazard zoning using the physics-environmental coupled Model

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Journal of Mountain Science 2023年第9期20卷 2644-2664页

作者： ZENG Ying ZHANG Ying-bin LIU Jing XU Pei-yi ZHU Hui YU Hai-hong he yun-yong Department of Geotechnical Engineering School of Civil EngineeringSouthwest Jiaotong UniversityChengdu 610031China CREC Sichuan Eco-City Investment Co. Ltd.Chengdu 420562China Sichuan Highway Planning SurveyDesign and Research Institute Ltd.Chengdu 610041China

In order to prevent and mitigate disasters,it is crucial to immediately and properly assess the spatial distribution of landslide hazards in the earthquake-affected ***,there are primarily two categories of assessment techniques:the physical mechanism-based method(PMBM),which considers the landslide dynamics and has the advantages of effectiveness and proactivity;the environmental factor-based method(EFBM),which integrates the environmental conditions and has high *** order to obtain the spatial distribution of landslide hazards in the affected area with near realtime and high accuracy,this study proposed to combine the PMBM based on Newmark method with EFBM to form Newmark-Information value model(N-IV),Newmark-Logic regression model(N-LR)and Newmark-Support Vector Machine model(N-SVM)for seismic landslide hazard assessment on the Ludian Mw 6.2 earthquake in *** predicted spatial hazard distribution was compared with the actual cataloged landslide inventory,and frequency ratio(FR),and area under the curve(AUC)metrics were used to verify the model's plausibility,performance,and *** to the findings,the model's accuracy is ranked as follows:N-SVM>N-LR>N-IV>*** an AUC value of 0.937,the linked N-SVM was discovered to have the best *** research results indicate that the physics-environmental coupled model(PECM)exhibits accuracy gains of 46.406%(N-SVM),30.625%(N-LR),and 22.816%(N-IV)when compared to the conventional Newmark *** shows varied degrees of improvement from 2.577%to 12.446%when compared to the single *** study also uses the Ms 6.8 Luding earthquake to evaluate the model,showcasing its trustworthy in forecasting power and steady *** the suggested PECM in this study can adapt to complicated earthquake-induced landslides situations,it aims to serve as a reference for future research in a similar field,as well as to help with emergency planning and response in earthquakepro

关键词： Earthquake-induced landslides Newmark method Coupled model Ludian earthquake Landslide distribution

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Constitutive model for Ya'an mudstone based on mesoscopic breakage mechanism

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Journal of Mountain Science 2023年第4期20卷 1159-1169页

作者： he yun-yong CheN Cong WANG Fu-ming GUO Cheng-chao XIANG Bo YU Di LIU En-long DING Chun School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China Sichuan Highway Planning SurveyDesign and Research Institute LtdChengdu610041China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu610065China School of Civil Engineering Sun Yat-sen UniversityGuangzhou510275China Ya’an Transportation Construction Group Co. Ltd.Ya’an625000China

The slope stability of Ya’an expressway in Sichuan dominated by mudstone strata,is influenced greatly by both the mechanical properties and stressstrain relationship of *** this paper,the mechanical properties of the Ya’an mudstone samples under triaxial compression conditions were studied,based on an established constitutive model under the framework of breakage mechanics to simulate the mechanical properties of ***,triaxial compression tests and SEM tests at the confining pressures of 0.5 MPa,1.0 MPa,and 2.0 MPa were carried out on the mudstone samples,and it was found that the mudstone sample undergoes strain softening and dilatancy followed by the volumetric ***,based on analysis on the breakage mechanism of the above test results,we idealized the mudstone sample as a binary medium material consisting of the bonded elements and frictional elements,of which the bonded elements are composed of solid matrix and pores,and the frictional elements are composed of broken *** the loading process,the cementation between clay minerals and non-clay minerals in the mudstone sample is first destroyed,leading to the formation of micro-cracks within the particle aggregate,that is,the bonded elements are gradually damaged during the loading process and gradually turned into the frictional elements,and the two jointly bear the external *** bonded elements are composed of mudstone matrix and pores,which have the cementitious characteristics of mudstone,and the frictional elements are composed of the broken aggregate with the frictional characteristics of the broken *** on the homogenization theory,the constitutive model for the mudstone is established,and the determining method for model parameters is also ***,the results of the triaxial compression tests of the mudstone samples are predicted by the constitutive model proposed here,which can reflect the main mechanical properties of the mudstone samples.

关键词： Mudstone Breakage mechanism Constitutive model Strain softening Binary medium model

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Effects of the probability of pulse-like ground motions on landslide susceptibility assessment in near-fault areas

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Journal of Mountain Science 2023年第1期20卷 31-48页

作者： LIU Jing FU Hai-ying ZHANG Ying-bin XU Pei-yi HAO Run-dan YU Hai-hong he yun-yong DENG Hong-yan ZheNG Lu Department of Geotechnical Engineering School of Civil EngineeringSouthwest Jiaotong UniversityChengdu610031China CREC Sichuan Eco-City Investment Co. Ltd.Chengdu620562China Sichuan Highway Planning SurveyDesign and Research Institute Ltd.Chengdu610041China Department of Track and Underground Engineering School of Civil EngineeringFuzhou UniversityFuzhou350108China

Earthquake-induced strong near-fault ground motion is typically accompanied by largevelocity pulse-like component,which causes serious damage to slopes and *** not all near-fault ground motions contain a pulse-like component,it is important to consider this factor in regional earthquake-induced landslide susceptibility *** the present study,we considered the probability of the observed pulse-like ground motion at each site(PP)in the region of an earthquake as one of the conditioning factors for landslide susceptibility assessment.A subset of the area affected by the 1994Mw6.7 Northridge earthquake in California was *** explore and verify the effects of PP on landslide susceptibility assessment,seven models were established,consisting of six identical influencing factors(elevation,slope gradient,aspect,distance to drainage,distance to roads,and geology)and one or two factors characterizing the intensity of the earthquake(distance to fault,peak ground acceleration,peak ground velocity,and PP)in logistic regression *** results showed that the model considering PP performed better in susceptibility assessment,with an area under the receiver operating characteristic curve value of *** on the results of relative importance analysis,the contribution of the PP value to earthquakeinduced landslide susceptibility was ranked fourth after the slope gradient,elevation,and *** prediction performance of the model considering the pulse-like effect was better than that reported previously.A logistic regression model that considers the pulse-like effect can be applied in disaster prevention,mitigation,and construction planning in near-fault areas.

关键词： Earthquake Landslides Pulse-like ground motion Logistic regression Susceptibility assessment 1994 Northridge earthquake

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快走丝线切割加工断丝现象分析

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模具工业 2008年第5期34卷 68-70页

作者：何云勇温州职业技术学院浙江温州325035

对线切割加工中造成断丝的原因进行了分析,从钼丝本身质量、装丝的松紧程度及丝筒转速、丝筒换向频率、加工电参数选择、加工工件材料性能、乳化液质量与运丝系统的稳定性等方面找出预防断丝的措施,可为从事线切割加工的人员提供参考。

关键词：线切割断丝加工

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一种分析曲线箱梁剪力滞效应的传递矩阵法

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重庆交通大学学报（自然科学版） 2010年第5期29卷 670-673页

作者：何云勇西南交通大学土木工程学院四川成都610031

基于能量泛函变分原理及箱梁翼板的剪力滞翘曲位移函数,导出了曲线箱梁的弹性控制微分方程、边界条件并运用消元法求得其闭合解。基于多跨曲线桥跨界的静力平衡及连续条件,给出了跨间矩阵和节点矩阵,建立了变形和内力的传递矩阵,提出了... 详细信息

基于能量泛函变分原理及箱梁翼板的剪力滞翘曲位移函数,导出了曲线箱梁的弹性控制微分方程、边界条件并运用消元法求得其闭合解。基于多跨曲线桥跨界的静力平衡及连续条件,给出了跨间矩阵和节点矩阵,建立了变形和内力的传递矩阵,提出了一种计算曲线箱梁剪力滞的传递矩阵法。算例表明了该方法的有效性。

关键词：曲线箱梁桥剪力滞效应跨间矩阵节点矩阵传递矩阵法

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一个新的人类N末端乙酰转移酶基因的克隆及其表达

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生物化学与生物物理学报 2002年第3期34卷 353-357页

作者：何云刚谢永芳陈瑶钱伟赖建华谭德勇云南大学生物技术系云南大学生物技术系昆明650091

乙酰化修饰普遍发生于真核生物的各种蛋白质 ,对蛋白质的稳定性和活性产生重大影响。酵母N末端乙酰基转移酶NatA由NAT1和ARD1两个亚基组成。任何一个亚基缺陷都导致NatA活性丧失 ,酵母表现出在接合型转换、细胞周期调控及染色体稳定性... 详细信息

乙酰化修饰普遍发生于真核生物的各种蛋白质 ,对蛋白质的稳定性和活性产生重大影响。酵母N末端乙酰基转移酶NatA由NAT1和ARD1两个亚基组成。任何一个亚基缺陷都导致NatA活性丧失 ,酵母表现出在接合型转换、细胞周期调控及染色体稳定性等方面的异常。通过同源克隆方法 ,克隆了与酵母NAT1高度同源的一个人类基因。经GenBank查询 ,为新基因 ,命名为HNAT1。原位杂交结果显示 ,在成年小鼠曲精管内 ,该基因的表达强烈。其表达强度与细胞类型和细胞所处时相有关。该基因在精子发生过程中可能具有重要作用

关键词： N末端乙酰基转移酶精子发生原位杂交基因克隆

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JH70拨叉热模锻工艺与模具设计

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模具工业 2009年第4期35卷 57-60页

作者：何云勇温州职业技术学院浙江温州325035

根据JH70换档拨叉产品图设计了适合摩擦压力机热模锻成型工艺的模锻件毛坯,对原热模锻成型工艺及模具进行了改进设计,对同类热模锻件的成型工艺与模具设计具有指导价值。

关键词：拨叉热模锻成型模具

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连续刚构桥船桥碰撞的计算模型和动力响应

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重庆交通大学学报（自然科学版） 2010年第4期29卷 501-505页

作者：罗旗帜何云勇徐中山湖南大学土木工程学院湖南长沙410082 佛山科学技术学院土木工程与建筑系广东佛山528000 西南交通大学土木工程学院四川成都610031 华南理工大学土木与交通学院广东广州510641

以连续钢构桥为例,基于碰撞理论和边界等代原理,研究了船桥碰撞的计算模型;基于Timoshenko剪切变形理论和Hamilton能量泛函变分原理,考虑桥墩的弯曲、剪切、地基效应和上部结构的影响,导出了碰撞体系的动力微分方程;采用积分变换方法,... 详细信息

以连续钢构桥为例,基于碰撞理论和边界等代原理,研究了船桥碰撞的计算模型;基于Timoshenko剪切变形理论和Hamilton能量泛函变分原理,考虑桥墩的弯曲、剪切、地基效应和上部结构的影响,导出了碰撞体系的动力微分方程;采用积分变换方法,对碰撞体系的控制微分方程和边界条件进行Laplace变换,在频域内求得波动解;运用Crump逆变换方法,使用数学软件Matlab编程进行数值反演,得到时域内的撞击力和各种动力响应。

关键词：连续刚构桥船桥碰撞计算模型动力响应

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结构面特征对顺层边坡开挖卸荷影响分析

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公路 2022年第6期67卷 1-7页

作者：何云勇李蜀南向波马建林西南交通大学土木工程学院成都市610031 四川省公路规划勘察设计研究院有限公司成都市610000 中国电建集团华东勘测设计研究院有限公司交通市政工程院杭州市311122

以四川省雅安市名山区某高速公路灌口组粉砂质泥岩顺层边坡为工程背景,利用现场大型直剪试验地质参数,建立了数值分析模型,以现场施工监测数据验证了模型的准确性,分析了顺层边坡结构面倾角、间距对边坡开挖卸荷及稳定性的影响。结果表... 详细信息

以四川省雅安市名山区某高速公路灌口组粉砂质泥岩顺层边坡为工程背景,利用现场大型直剪试验地质参数,建立了数值分析模型,以现场施工监测数据验证了模型的准确性,分析了顺层边坡结构面倾角、间距对边坡开挖卸荷及稳定性的影响。结果表明,顺层边坡卸荷区随开挖级数增加而不断扩展,呈现上宽下窄的分布特征,开挖卸荷深度随开挖级数增加迅速减小,深高比随顺层边坡开挖级数增加逐渐减小;顺层边坡安全系数随结构面倾角增大先减小后增大,开挖卸荷导致结构面最不利倾角由20°变化为30°,此时边坡卸荷深度及位移变形量最大;结构面间距对顺层边坡开挖安全系数及稳定性影响较小,但结构面密集边坡的位移变形量远大于结构面稀疏边坡,两者最大水平位移相差近5倍。研究结果可为该地区工程边坡防护设计提供有益的借鉴与参考。

关键词：道路工程红层泥岩顺层边坡结构面开挖卸荷稳定性

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