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Life Loss Estimation Based on Dam-Break Flood Uncertainties and Lack of Information in Mountainous Regions of Western China

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Transactions of Tianjin University 2017年第4期23卷 370-379页

作者： Chao Wang Sherong Zhang yaosheng tan Fei Pan Lei Yan School of Civil Engineering Tianjin University Tianjin 300072 China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China China Three Gorges Corporation Chengdu 610051 China HydroChina Kunming Engineering Corporation Kunming 650051 China

Compared with urban floods, dam-break floods are associated with greater uncertainties, including variable dam-break modes and hydrological characteristics, so conventional flood estimation methods cannot be directly applied in the estimation of dam-break flood loss. In particular, there is scant information regarding the conditions of affected area and hydrological characteristics in southwest China. In this paper, we introduce an integrated model for estimating flood loss that is adapted to the mountainous regions of southwestern China in light of the relative lack of available information. This model has three major components: a basic information model, a dam-routed flood propagation simulation model, and a loss estimation model. We established the basic information model despite the relative lack of available information using 3S technology [remote sensing(RS); geographical information system(GIS); global positioning system(GPS)], data mining technology, and statistical analysis techniques. Our dam-routed flood propagation simulation model consists of major hydrologic processes and their governing equations for flow propagation, which we solve using finite-difference schemes. In this model, the flood propagation area is divided into grids and each grid is determined by the characteristic parameters obtained from the propagationsimulation. We present a case study of the Lianghekou hydropower station in Sichuan Province, China to illustrate the practical application of this integrated model for life loss estimation.

关键词： Life loss estimation model Lack of information Dam-break flood Basic information model

考虑黏聚力及不完全拱效应的太沙基松动土压力

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地下空间与工程学报 2024年第3期20卷 748-756页

作者：董顺张翰高潮淦方茂谭尧升中国长江三峡集团有限公司武汉430010 长江生态环保集团有限公司武汉430077

考虑滑移面上主应力旋转和埋深对侧向土压力系数的影响,基于摩尔-库伦(Mohr-Coulomb)破坏准则推导黏聚力存在时滑移面上的侧向土压力系数,进而采用微分土条极限平衡方法推导滑移面上的竖向应力。在此基础上,假设小主应力轨迹为圆弧,进... 详细信息

考虑滑移面上主应力旋转和埋深对侧向土压力系数的影响,基于摩尔-库伦(Mohr-Coulomb)破坏准则推导黏聚力存在时滑移面上的侧向土压力系数,进而采用微分土条极限平衡方法推导滑移面上的竖向应力。在此基础上,假设小主应力轨迹为圆弧,进而推导不完全拱效应作用下滑移面间的竖向应力分布及平均竖向应力。结果表明:与传统太沙基(Terzaghi)松动土压力公式及其现有修正公式相比,本文推导的滑移面上的竖向应力受黏聚力和内摩擦角的影响更加显著,且滑移面上的主应力旋转会放大二者对滑移面上竖向应力的影响;黏聚力对滑移面间竖向应力及侧向土压力系数的横向分布具有相同的影响规律,即黏聚力越大,二者的非线性分布特征越显著;以小主应力轨迹为圆弧所得出的滑移面间竖向应力分布规律与杨明辉等的原位测试结果基本吻合,且活门上的平均竖向应力与Chevalier等的试验结果较为吻合。

关键词：主应力旋转黏聚力不完全拱效应松动土压力

Simulation of Temperature Field of High Arch Dams Considering Solar Radiation

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Simulation of Temperature Field of High Arch Dams Considerin...

作者： Zhenyang Zhu Yi Liu yaosheng tan State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research China Three Gorges Projects Development Co. Ltd

Due to factors such as seasonal variations in the solar azimuth angle and the masking of a dam body by itself or by a mountain,different areas of a high arch dam absorb significantly different amounts of solar radiation,which is likely to result in an uneven temperature distribution on the surface of the high arch dam and,subsequently,in unfavorable stress during the high arch dam’s construction and operation.Therefore,in calculations of the dam body’s temperature and for crack control,the effect of solar radiation should be taken into account accurately.Based on the mask algorithm,as well as local meteorological conditions,the effect of solar radiation is included in simulations of temperature and for crack control in high arch dams in the southwestern region.The engineering examples show that when solar radiation is included,the calculation’s accuracy improves significantly.

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白鹤滩水电站蓄水过程左岸厂区渗控效果评价

水力发电学报 2022年第10期41卷 42-52页

作者：邱钦焱荣冠谭尧升张胡琦徐李达武汉大学水资源与水电工程科学国家重点实验室武汉430072 中国长江三峡集团有限公司北京100038 中国三峡建工(集团)有限公司成都610041

白鹤滩水电站左岸地质条件复杂,发育层间错动带、层内错动带和柱状节理玄武岩等软弱地质结构。左岸厂区布置大规模的防渗排水系统,合理有效地评价其渗控效果对水电站的安全运行有着重要的指导意义。结合2021年4月—2022年3月蓄水过程的... 详细信息

白鹤滩水电站左岸地质条件复杂,发育层间错动带、层内错动带和柱状节理玄武岩等软弱地质结构。左岸厂区布置大规模的防渗排水系统,合理有效地评价其渗控效果对水电站的安全运行有着重要的指导意义。结合2021年4月—2022年3月蓄水过程的监测成果分析白鹤滩水电站左岸厂区渗流规律,评价渗控效果。结果表明:左岸厂区最大渗流量为1249.14 L/min,总渗流量明显受上游水位变化影响,第3、7层排灌廊道渗流量占总渗流量的69.5%。防渗帷幕部位的压力水头随高程的降低而增加,C_(2)位置压力水头明显增大。结构面C_(3)、C_(3-1)、C_(2)和LS_(3152)是渗透薄弱部位,其渗流量较大,渗压水位随上游水位变化明显,容易成为渗漏通道。从整体上看,厂区的排水孔幕能有效消减压力水头,总渗流量维持在合理范围内,总体渗控效果良好。

关键词：白鹤滩水电站地下厂房渗流规律渗控效果渗漏通道

Single-base editing in IGF2 improves meat production and intramuscular fat deposition in Liang Guang Small Spotted pigs

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Journal of Animal Science and Biotechnology 2024年第1期15卷 108-126页

作者： Tianqi Duo Xiaohong Liu Delin Mo Yu Bian Shufang Cai Min Wang Ruiqiang Li Qi Zhu Xian Tong Ziyun Liang Weilun Jiang Shiyi Chen yaosheng Chen Zuyong He State Key Laboratory of Biocontrol School of Life SciencesSun Yat-Sen UniversityGuangzhou 510275GuangdongChina Department of Pharmacology(the State‑Province Key Laboratories of Biomedicine‑Pharmaceutics of China Key Laboratory of Cardiovascular ResearchMinistry of Education)College of PharmacyHarbin Medical UniversityHarbin 150081China Hunan Provincial Key Laboratory for Genetic Improvement of Domestic Animal College of Animal Science and TechnologyHunan Agricultural UniversityChangsha 410128China

Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor that promotes skeletal muscle growth by regulating cell proliferation and differentiation.A single nucleotide polymorphism(SNP) within intron 3 of porcine IGF2 disrupts a binding site for the repressor,zinc finger BED-type containing 6(ZBED6),leading to up-regulation of IGF2 and causing major effects on muscle growth,heart size,and backfat thickness.This favorable mutation is common in Western commercial pig populations,but absent in most Chinese indigenous pig breeds.To improve meat production of Chinese indigenous pigs,we used cytosine base editor 3(CBE3)to introduce IGF2 intron3-C3071T mutation into porcine embryonic fibroblasts(PEFs) isolated from a male Liang Guang Small Spotted pig(LGSS),and single-cell clones harboring the desired mutation were selected for somatic cell nuclear transfer(SCNT) to generate the founder line of IGF2^(T/T) pigs.Results We found the heterozygous progeny IGF2^(C/T) pigs exhibited enhanced expression of IGF2,increased lean meat by 18%-36%,enlarged loin muscle area by 3%-17%,improved intramuscular fat(IMF) content by 18%-39%,marbling score by 0.75-1,meat color score by 0.53-1.25,and reduced backfat thickness by 5%-16%.The enhanced accumulation of intramuscular fat in IGF2^(C/T) pigs was identified to be regulated by the PI3K-AKT/AMPK pathway,which activated SREBP1 to promote adipogenesis.Conclusions We demonstrated the introduction of IGF2-intron3-C3071T in Chinese LGSS can improve both meat production and quality,and first identified the regulation of IMF deposition by IGF2 through SREBP1 via the PI3KAKT/AMPK signaling pathways.Our study provides a further understanding of the biological functions of IGF2and an example for improving porcine economic traits through precise base editing.

关键词： CBE3 IGF2 Intramuscular fat Meat production PI3K-AKT/AMPK ZBED6

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混凝土坝水平缝面智能冲毛系统研发及应用

水利学报 2023年第6期54卷 644-653,665页

作者：崔博程益骄关涛王晓玲谭尧升陈文夫天津大学水利工程仿真与安全国家重点实验室天津300350 中国长江三峡集团有限公司北京100038 中国三峡建工(集团)有限公司四川成都610041

新老混凝土水平施工缝面处理是确保坝体混凝土整体性的关键工序。目前混凝土坝施工主要根据经验采用高压水人工冲毛方式对冲毛位置、冲毛时间等进行控制,存在工作强度高、作业主观性强等不足,难以实现冲毛质量的精准控制。针对上述问题... 详细信息

新老混凝土水平施工缝面处理是确保坝体混凝土整体性的关键工序。目前混凝土坝施工主要根据经验采用高压水人工冲毛方式对冲毛位置、冲毛时间等进行控制,存在工作强度高、作业主观性强等不足,难以实现冲毛质量的精准控制。针对上述问题,本文研究了混凝土水平缝面智能冲毛系统。基于工业机器人、自动化控制等技术研制智能冲毛装备,实现混凝土坝仓面无人冲毛作业;耦合多源传感器信息,建立智能冲毛装备运动学模型以及路径规划方法,实现智能冲毛装备自主避障;结合机器视觉理论,建立基于卷积神经网络的混凝土冲毛表面图像智能分类模型,实现冲毛质量的客观分析;同时,开发云端监控平台和无线通讯子系统,实现与智能冲毛装备之间的信息传输和多平台互联互通,并进行智能冲毛装备的有效管理和远程控制。此外,通过现场试验验证了智能冲毛系统的可行性和可靠性,研究成果为混凝土坝冲毛施工实现无人化作业、科学化质量管控提供了新的思路和技术手段,具有十分重要的现实意义和应用价值。

关键词：混凝土坝水平缝面智能冲毛无人化作业路径规划机器视觉

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高拱坝混凝土振捣机器人系统研发及应用

水利学报 2022年第6期53卷 631-643,654页

作者：王晓玲王栋任炳昱陈文夫谭尧升关涛天津大学水利工程仿真与安全国家重点实验室天津300072 中国三峡建工(集团)有限公司四川成都610041 中国长江三峡集团有限公司北京100038

常态混凝土浇筑人工振捣施工存在工作强度高、作业主观性强等不足,现有振捣监控方法主要进行振捣位置、振捣时间等参数监控,且均依靠人工经验评估振捣是否密实,难以实现混凝土振捣质量的精确评估。针对上述问题,研发了融合表面图像机器... 详细信息

常态混凝土浇筑人工振捣施工存在工作强度高、作业主观性强等不足,现有振捣监控方法主要进行振捣位置、振捣时间等参数监控,且均依靠人工经验评估振捣是否密实,难以实现混凝土振捣质量的精确评估。针对上述问题,研发了融合表面图像机器视觉识别的混凝土振捣机器人系统,该系统包括振捣机器人本体、云端监控平台以及通讯子系统。基于工业机器人、自动化控制、机器视觉等技术研制振捣机器人本体,实现高拱坝仓面混凝土无人振捣作业;同时,建立基于改进残差网络(Residual Network,ResNet)的混凝土振捣表面图像的分类模型,实现振捣密实性的科学分析。此外,基于B/S架构研发云端监控平台,并通过无线通讯子系统实现与振捣机器人本体之间信息的传输与交互,实现振捣作业信息的可视化与远程控制。现场试验验证了振捣机器人系统的可靠性和可行性。研究成果为高拱坝混凝土振捣实现无人化作业、精细化质量控制提供了新的思路和技术手段,也可用于其它大体积混凝土施工中,具有十分重要的应用和推广价值。

关键词：高拱坝混凝土振捣振捣机器人系统机器视觉改进ResNet 表面图像分类

Influence of ambient temperature on the CO_(2)emitted of light-duty vehicle

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Journal of Environmental Sciences 2024年第6期140卷 59-68页

作者： Dan tan Yachao Wang Jianwei tan Jiachen Li Changyu Wang Yunshan Ge School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2.There was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and deceleration.The CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different vehicles.To separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was proposed.And results showed that the load setting was dominant for the CO_(2)emission variation.Compared with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.

关键词： CO_(2)emission Ambient temperature E10 gasoline Light-duty vehicle WLTC

Amorphous hybrid tungsten oxide–nickel hydroxide nanosheets used as a highly efficient electrocatalyst for hydrogen evolution reaction

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Nano Research 2024年第4期17卷 2499-2508页

作者： Chao Lyu Chenghai Dai Yiwei tan State Key Laboratory of Materials-Oriented Chemical Engineering School of Chemistry and Chemical EngineeringNanjing Tech UniversityNanjing 211816China

There are more challenges for alkaline hydrogen evolution reaction(HER)via simultaneously expediting the electron-coupled water dissociation process(Volmer step)and the following electrochemical H_(2) desorption(Heyrovsky step).Hybrid amorphous electrocatalysts are highly desirable for efficient hydrogen evolution from water-alkali electrolyzers due to the bifunctionality for the different elementary steps of HER and optimal interactions with water molecules and the reactive hydrogen intermediates(Had).Herein,the synthesis of amorphous hybrid ultrathin(tungsten oxide/nickel hydroxide)hydrate(a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O)nanosheets on nickel foam(NF)for efficient alkaline HER is described.The structural and composition features of a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O are characterized in detailed.The resulting a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O/NF electrocatalyst with the synergistic effect of both hybrid components for the HER elementary steps shows greatly improved the activity and durability for the HER with a low overpotential of-41 and-163 mV at-10 and-500 mA·cm^(-2),respectively,a Tafel slope as low as-72.9 mV·dec^(-1),and long-term stability of continuous electrolysis for at least 150 h accompanying by inappreciable overpotential change in 1 M KOH.In the hybrid a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O,Ni(OH)_(2) and WO_(3) moieties are separately responsible for accelerating dissociative adsorption of water and weakening Had adsorption strength,which is beneficial to the improvement of the alkaline HER activity.

关键词： amorphous nanomaterial bimetallic electrocatalyst tungsten oxide ultrathin nanosheet hydrogen evolution reaction