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Health risk assessment of heavy metal pollution in groundwater of a karst basin,SW China

Journal of Groundwater Science and engineering 2024年第1期12卷 49-61页

作者： Fu-ning Lan Yi Zhao Jun Li Xiu-qun Zhu Karst Ecosystem National Observation and Research StationPingguo 531406GuangxiChina Institute of Karst Geology International Research Centre on KarstUnder the Auspices of UNESCOGuangxi Karst Resources and Environment Research Center of Engineering TechnologyChinese Academy of Geological SciencesKarst Dynamics LaboratoryMNR and GuangxiGuilin 541004China Hebei Key Laboratory of Water Quality engineering and Comprehensive Utilization of Water Resources Hebei University of ArchitectureZhangjiakou 075000Hebei ProvinceChina College of Hydrology and Water Resources Hohai UniversityNanjing 210098China

To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Health risk assessment(HRA)model was employed to analyze 84 water samples from the *** detection results revealed the following order of heavy metals concentrations:Fe>Al>Mn>Zn>As>Cd>Pb>Cr>Ni>Cu>*** analysis indicated a certain similarity in material source and migration transformation among these eleven metal *** study identified that the health risks for local residents exposed to metal elements in the water of NURB primarily stem from carcinogenic risk(10^(−6)–10^(−4)a^(−1))through the drinking water ***,the health risk of heavy metal exposure for children through drinking water was notably higher than for *** maximum health risks of Cr in both underground and surface water exceeded the recommendation standard(5.0×10^(−5)a^(−1))from ICRP,surpassing the values recommended by the Swedish Environmental Protection Agency,the Dutch Ministry of construction and Environment and the British Royal Society(5.0×10^(−6)a^(−1)).The results of the health risk assessment indicate that Cr in the water of NURB is the primary source of carcinogenic risk for local residents,followed by Cd and ***,it is imperative to control these three carcinogenic metals when the water was used as drinking water resource.

关键词： Water Pollution Correlation Analysis Toxicity of Heavy Metal Elements Underground River Basin Carcinogenicity Potential

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Models to Simulate Effective Coverage of Fire station Based on Real-Time Travel Times

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Computer Modeling in engineering & Sciences 2024年第4期139卷 483-513页

作者： Sicheng Zhu Dingli Liu Weijun Liu Ying Li Tian Zhou Department of engineering Management Changsha University of Science and TechnologyChangsha410114China

In recent years,frequent fire disasters have led to enormous damage in *** firefighting rescues can minimize the losses caused by *** the rescue processes,the travel time of fire trucks can be severely affected by traffic conditions,changing the effective coverage of fire ***,it is still challenging to determine the effective coverage of fire stations considering dynamic traffic *** paper addresses this issue by combining the traveling time calculationmodelwith the effective coverage *** addition,it proposes a new index of total effective coverage area(TECA)based on the time-weighted average of the effective coverage area(ECA)to evaluate the urban fire *** also selects China as the case study to validate the feasibility of the models,a fire station(FS-JX)in ***-JX station and its surrounding 9,117 fire risk points are selected as the fire service supply and demand points,respectively.A total of 196 simulation scenarios throughout a consecutiveweek are ***,1,933,815 sets of valid sample data are *** results showed that the TECA of FS-JX is 3.27 km^(2),which is far below the standard requirement of 7.00 km^(2) due to the traffic *** visualization results showed that three rivers around FS-JX interrupt the continuity of its effective *** proposed method can provide data support to optimize the locations of fire stations by accurately and dynamically determining the effective coverage of fire stations.

关键词： Fire services fire station effective coverage real-time traffic simulation

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Instance Segmentation and Berry Counting of Table Grape before Thinning Based on AS-SwinT

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Plant Phenomics 2023年第4期5卷 703-713页

作者： Wensheng Du Ping Liu Shandong Agricultural Equipment Intelligent engineering Laboratory Shandong Provincial Key Laboratory of HorticulturalMachinery and EquipmentCollege of Mechanical and Electronic EngineeringShandong Agricultural UniversityTai'an 271000China School of construction Machinery Shandong Jiaotong UniversityJinan 250357China

Berry thinning is one of the most important tasks in the management of high-quality table *** often thin the berries per cluster to a standard number by *** an aging population,it is hard to find adequate skilled farmers to work during thinning *** is urgent to design an intelligent berry-thinning machine to avoid exhaustive repetitive labor.A machine vision system that can determine the number of berries removed and locate the berries removed is a challenge for the thinning machine.A method for instance segmentation of berries and berry counting in a single bunch is proposed based on *** AS-Swin T,Swin Transformer is performed as the backbone to extract the rich characteristics of grape *** adaptive feature fusion is introduced to the neck network to sufficiently preserve the underlying features and enhance the detection of small *** size of berries in the dataset is statistically analyzed to optimize the anchor scale,and Soft-NMS is used to filter the candidate frames to reduce the missed detection of densely shaded ***,the proposed method could achieve 65.7 AP^(box),95.0 AP^(box)_(0.5),57 AP^(box)_(s),62.8 AP^(mask)94.3 AP^(mask)_(0.5),48 AP^(mask)_(s),which is markedly superior to Mask R-CNN,Mask Scoring R-CNN,and Cascade Mask *** regressions between predicted numbers and actual numbers are also developed to verify the precision of the proposed *** and R^(2)values are 7.13 and 0.95,respectively,which are substantially higher than other models,showing the advantage of the AS-SwinT model in berry counting estimation.

关键词： Berry network removed

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Development and Field Application of Phosphogypsum-Based Soil Subgrade Stabilizers

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Journal of Renewable Materials 2022年第8期10卷 2247-2261页

作者： Hongfei Yue Aiguo Fang Sudong Hua Zenghuan Gu Yu Jia Cheng Yang College of Materials Science and engineering Nanjing Tech UniversityNanjing211800China China construction Installaction engineering Co. Ltd.Nanjing210023China jiangsu Subote New Material Co. Ltd.Nanjing211103China Sinoma construction Co. Ltd.Suzhou215300China

A phosphogypsum-based subgrade stabilizer(PBSS)was formulated using industrial by-product phosphogypsum(PG),mixed with slag and calcium-silicon-rich active material(GSR).The active powder(AP)was used to modify PBSS,and PBSS-AP was *** and PBSS-AP were each mixed with 10%silty soil,and cement and lime(CAL:5%lime+2%cement)were used as the traditional material for comparative *** were cured under standard conditions,and tested for unconfined compressive strength(UCS),water stability,volume expansion,and leachate,to explore the stabilization effect of the three solidified materials on silty *** results showed that the comprehensive performance of sility soil mixed with 12%PBSS-AP was the *** CaO,SiO_(2)and Al_(2)O_(3)provided by PG,Slag and GSR will react with water to form a stable C-S-H gel,which is conducive to stabilizing the *** application results showed that the compaction exceeded 95%,the deflection was 144.9 mm,and UCS was 2.5 MPa after 28 *** findings indicated that PBSS-AP is an effective stabilizer for subgrade soils.

关键词： Phosphogypsum solidified material unconfined compressive strength water stability volume expansion leachate

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Practice and experience of engineering culture development in the Sutong Bridge project

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engineering Sciences 2009年第1期7卷 87-92页

作者： Yu Chunsheng Yao Bei Wang Qian jiangsu provincial Sutong Bridge construction Commanding Department Nanjing 210006China School of Management ＆ engineering Nanjing University Nanjing 210093 China

To keep up with the time,culture is integrated to large-scale construction project management in China,which will absolutely add more vitality into construction project management in our *** culture is an integration of project construction and engineering ***,engineering culture development enjoys its own particularity as a project is constructed once only within a limited period of *** paper gives affirmative opinion that engineering culture development in large-scale projects backs project management on the basis of thorough investigation of engineering culture development in Sutong Bridge Project and after deepened analysis,proposes new thinking pattern of engineering culture development in large-scale projects in a systematic manner,including thorough understanding of the essence of engineering culture,principle and contents of engineering culture development as well as efficient method in respect of establishment and implementation of engineering culture,and therefore provides a standard reference and systematic thinking pattern for engineering culture development in future large-scale projects.

关键词： large-scale projects engineering culture engineering culture development systematic thinking pattern

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Vehicle-bridge coupled vibrations in different types of cable stayed bridges

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Frontiers of Structural and Civil engineering 2016年第1期10卷 81-92页

作者： Lingbo WANG Peiwen JIANG Zhentao HUI Yinping MA Kai LIU Xin KANG Key Laboratory for Bridee and Tunnel of Shaanxi Province. Chang'an University. Xi'an 710064. China Basic construction Project Quality Supervision station Shaanxi Provincial Transport Department Xi'an 710075 China Yulin TianYuan Lu Ye Limited Company 25 Shangjun Road Yuyang District Yulin 719000 China School of Transportation engineering Hefei University of Technology Hefei 230009 China Department of Civil Architectural and Environmental Engineering Missouri University of Science and Technology Rolla MO65409 USA

Numerical analyses of the coupled vibrations of vehicle-bridge system and the effects of different types of cable stayed bridges on the coupled vibration responses have been presented in this paper using ANSYS. The bridge model and vehicle model were independently built which have no internal relationship in the ANSYS. The vehicle-bridge coupled vibration relationship was obtained by using the APDL program which subsequently imposed on the vehicle and bridge models during the numerical analysis. The proposed model was validated through a field measurements and literature data. The judging method, possibility, and criterion of the vehicle-bridge resonance （coupled vibrations） of cable stayed bridges （both the floating system and half floating system） under traffic flows were presented. The results indicated that the interval time between vehicles is the main influence factor on the resonance excitation frequency under the condition of equally spaced traffic flows. Compared to other types of cable stayed bridges, the floating bridge system has relatively high possibility to cause vehicle-bridge resonance.

关键词： vehicle-bridge coupled vibration cable stayed bridge resonances of vehicle-bridge system

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An ultra-accurate dynamic isogeometric analysis with higher order mass formulation

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Science China(Technological Sciences) 2014年第7期57卷 1293-1309页

作者： WANG DongDong LI XiWei LIU Wei ZHANG HanJie Department of Civil engineering Xiamen University Fujian provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computation Xiamen University

An ultra-accurate isogeometric dynamic analysis is *** key ingredient of the proposed methodology is the development of isogeometric higher order mass matrix.A new one-step method is proposed for the construction of higher order mass *** this approach,an adjustable mass matrix is formulated through introducing a set of mass parameters into the consistent mass matrix under the element mass conservation *** the semi-discrete frequency derived from the free vibration equation with the adjustable mass matrix is served as a measure to optimize the mass *** 1D analysis,it turns out that the present one-step method can perfectly recover the existing reduced bandwidth mass matrix and the higher order mass matrix by choosing different mass ***,the employment of the proposed one-step method to the2D membrane problem yields a remarkable gain of solution accuracy compared with the higher order mass matrix generated by the original two-step *** a full-discrete isogeometric transient analysis algorithm is presented by using the Newmark time integration scheme and the higher order mass *** full-discrete frequency is derived to assess the accuracy of space-time *** a set of numerical examples are presented to evaluate the accuracy of the proposed method,which show that very favorable solution accuracy is achieved by the present dynamic isogeometric analysis with higher order mass formulation compared with that obtained from the standard consistent mass approach.

关键词： isogeometric analysis dynamics semi-discrete frequency full-discrete frequency higher order mass matrix

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Monitoring Study of Long-Term Land Subsidence during Subway Operation in High-Density Urban Areas Based on DInSAR-GPS-GIS Technology and Numerical Simulation

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Computer Modeling in engineering & Sciences 2023年第2期134卷 1021-1039页

作者： Yu Song Xuejun Chen Baoping Zou Jundong Mu Rusheng Hu Siqi Cheng Shengli Zhao College of Civil and Architecture engineering Guilin University of TechnologyGuilin541004China School of Civil engineering and Architecture Zhejiang University of Science and TechnologyHangzhou310023China Hangzhou Metro Group Co. Ltd.Hangzhou310003China China Railway Tunnel Bureau Group Co. Ltd.Guangzhou511458China General Supervision station of construction engineering Quality and Safety of Hangzhou Hangzhou310005China

During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil during tunnel construction,dense buildings and structures in the vicinity of the tunnel,and changes in water level in the stratum where the tunnel is *** monitoring of long-term land subsidence during subway operation in high-density urban areas differs from that in low-density urban construction *** former is the gathering point of the entire urban *** are many complex buildings around the project,busy road traffic,high pedestrian flow,and less vegetation *** existing items ***,monitoring distance is long,and providing early warning is *** study uses the 2.8 km operation line between Wulin Square station and Ding’an Road station of Hangzhou Subway Line 1 as an example to propose the integrated method of DInSAR-GPS-GIS technology and the key algorithm for long-term land subsidence ***,it selects multiscene image data to analyze long-termland subsidence of high-density urban areas during subway *** show that long-term land subsidence caused by the operation of Wulin Square station to Ding’an Road station of Hangzhou Subway Line 1 is small,with maximumsubsidence of 30.64 mm,and minimumsubsidence of 11.45 mm,and average subsidence ranging from 19.27 to 21.33 *** FLAC3D software was used to verify the monitoring situation,using the geological conditions of the soil in the study area and the tunnel profile to simulate the settlement under vehicle load,and the simulation results tended to be consistent with the monitoring situation.

关键词： Long-term land subsidence subway operation DInSAR-GPS-GIS technology high-density urban areas urban subway numerical simulation

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横风中桥隧过渡段移动列车的气动特性试验研究

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Journal of Central South University 2023年第2期30卷 613-624页

作者：唐林波何旭辉严磊林泽 School of Civil engineering Central South UniversityChangsha 410075China National engineering Research Center for High-speed Railway construction Changsha 410075China Hunan provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit engineering Structures Changsha 410075China

本文通过缩尺比为1:16.8的复兴号动模型试验研究了横风中移动列车经过桥隧过渡段时的气动特性。该试验在中南大学风洞实验室自主研发的弹射模型实验装置上进行,移动列车表面的气动压力通过装载在车体内的无线测压系统获得,并可通过积分... 详细信息

本文通过缩尺比为1:16.8的复兴号动模型试验研究了横风中移动列车经过桥隧过渡段时的气动特性。该试验在中南大学风洞实验室自主研发的弹射模型实验装置上进行,移动列车表面的气动压力通过装载在车体内的无线测压系统获得,并可通过积分获得列车气动力。实验结果表明,横风中移动列车经过桥隧过渡段时,列车侧向力会发生先负后正或先正后负的剧烈变化,列车迎风面压力标准差大于背风面压力标准差。在迎、背风侧轨道上运行的移动列车经过桥隧过渡段时所受气动力变化规律相似,迎风侧轨道上移动列车在隧道洞口处所受侧向力一般比其在背风侧轨道时的大;其主要原因是相对于背风侧轨道上的列车,迎风侧轨道上的列车迎风面所受负压更小,背风面所受负压更大。

关键词：横风移动列车桥隧过渡段风压测量轨道位置风洞试验

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Analysis of Topographic Heterogeneity in the Sanjiangyuan

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Asian Agricultural Research 2021年第6期13卷 40-41,63页

作者： Dan WU Hui KONG Shaanxi provincial Land engineering construction Group Co. Ltd.Xi'an 710075China Institute of Land engineering and Technology Shaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi'an 710075China Key Laboratory of Degraded and Unused Land Consolidation engineering Ministry of Natural ResourcesXi'an 710075China Shaanxi provincial Land Consolidation engineering Technology Research Center Xi'an 710075China

Based on the DEM raster image data with a resolution of 60 m×60 m in the Sanjiangyuan region,the topographic heterogeneity in the Sanjiangyuan region was analyzed by calculating and processing the topographic relief,elevation standard deviation,terrain heterogeneity and surface roughness *** results show that the overall terrain elevation of the Sanjiangyuan area is high,and the surface undulations are *** southern and southeastern parts of the region are the places with the most dramatic terrain *** absolute values of terrain undulations,elevation standard deviation and surface roughness are *** the central and western regions,the terrain change is small,the relief degree is small,the elevation standard deviation and the surface roughness are small.

关键词： Topographic heterogeneity Relief of topography Surface roughness

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