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融合GLAS与Landsat的湖泊蓄水量季节性监测及预测
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作者 王振华 刘存锟 +2 位作者 张熙 王凤香 刘向锋 《海洋测绘》 CSCD 北大核心 2024年第4期74-78,共5页
为实现高海拔区域湖泊蓄水量监测与预测,提出了一种融合ICESat/GLAS与Landsat数据监测并预测湖泊蓄水量季节性变化的方法。利用随机森林对GLAS激光脚点自动分类,解决湖面非水体与水体目标分类难的问题;结合水体指数和大津法自动分割Land... 为实现高海拔区域湖泊蓄水量监测与预测,提出了一种融合ICESat/GLAS与Landsat数据监测并预测湖泊蓄水量季节性变化的方法。利用随机森林对GLAS激光脚点自动分类,解决湖面非水体与水体目标分类难的问题;结合水体指数和大津法自动分割Landsat数据中的水体,降低不规则边界的影响;联合GLAS和Landsat数据,构建高时间分辨率的水位、面积与蓄水量时序列变化关系,解决两类数据观测信息缺失及观测时间不匹配的问题;并利用LSTM模型,预测蓄水量变化。以西藏纳木错湖为例,对上述方法进行验证,结果显示2003-2009年纳木错湖水位上升1.15 m,面积增加25.58 km2,蓄水量增加2.30 km^(3);预测2010-2016年蓄水量增加1.16 km^(3),与实际情况相符。结果表明,该方法可为生态环境的动态监测提供数据支撑。 展开更多
关键词 激光脚点分类 蓄水量预测 水位计算 水体分类 季节性监测
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Fiber optic sensing and performance evaluation of a water conveyance tunnel with composite linings under super-high internal pressures 被引量:2
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作者 Deyang Wang Honghu Zhu +3 位作者 Jingwu Huang Zhenrui Yan Xing Zheng Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第8期1997-2012,共16页
For long-distance water conveyance shield tunnels in operation,the high internal water pressure may cause excessive deformation of composite linings,affecting their structural integrity and serviceability.However,the ... For long-distance water conveyance shield tunnels in operation,the high internal water pressure may cause excessive deformation of composite linings,affecting their structural integrity and serviceability.However,the deformation and failure characteristics of lining structures under internal water pressure are not well investigated in the literature,particularly for three-layer composite linings.This study presents an in situ experimental investigation on the response of two types of composite linings(i.e.separated and combined lining structures)subjected to internal pressures,in which a fiber optic nerve system(FONS)equipped with distributed strain and displacement sensing nerves was employed to monitor the performance of the two composite linings during testing.The experimental results clearly show that the damage of the tunnel lining under different internal pressures was mainly located in the self-compaction concrete layer.The separated lining structure responded more aggressively to the variations in internal pressures than the combined one.Moreover,two evaluation indices,i.e.radial displacement and effective stiffness coefficient,are proposed for describing the changes in the structural bearing performance.The effective stiffness coefficients of the two types of lining structures were reduced by 39.4%and 29.5%,respectively.Considering the convenience of field monitoring,it is suggested that the average strains at different layers can be used as characteristic parameters for estimating the health conditions of lining structures in service.The analysis results provide a practical reference for the design and health evaluation of water conveyance shield tunnels with composite linings. 展开更多
关键词 water conveyance tunnel Composite lining interface Strain measurement Geotechnical monitoring Fiber optic nerve system(FONS)
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Online dynamic measurement of saturation-capillary pressure relation in sandy medium under water level fluctuation 被引量:1
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作者 李雁 周劲风 +1 位作者 徐军 KAMON M 《Journal of Central South University》 SCIE EI CAS 2010年第1期85-92,共8页
An online dynamic method based on electrical conductivity probe, tensiometer and datataker was presented to measure saturation-capillary pressure (S-p) relation in water-light nonaqueous phase liquid (LNAPL) two-p... An online dynamic method based on electrical conductivity probe, tensiometer and datataker was presented to measure saturation-capillary pressure (S-p) relation in water-light nonaqueous phase liquid (LNAPL) two-phase sandy medium under water level fluctuation. Three-electrode electrical conductivity probe (ECP) was used to measure water saturation. Hydrophobic tensiometer was obtained by spraying waterproof material to the ceramic cup of commercially available hydrophilic tensiometer. A couple of hydrophilic tensiometer and hydrophobic tensiometer were used to measure pore water pressure and pore LNAPL pressure of the sandy medium, respectively. All the signals from ECP and tensiometer were collected by a data taker connected with a computer. The results show that this method can finish the measurement of S-R relation of a complete drainage or imbibition process in less than 60 min. It is much more timesaving compared with 10-40 d of traditional methods. Two cycles of water level fluctuation were produced, and four saturation-capillary pressure relations including two stable residual LNAPL saturations of the sandy medium were obtained during in 350 h. The results show that this method has a good durable performance and feasibility in the porous medium with complicated multiphase flow. Although further studies are needed on the signal stability and accuracy drift of the ECP, this online dynamic method can be used successfully in the rapid characterization of a LNAPL migration in porous media. 展开更多
关键词 water level fluctuation saturation-capillary pressure (S-p) relation online dynamic measurement
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The Design Liquid-level Monitoring System of Adopting the Ultrasonic Sensing Technology
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作者 LI JING YAO YANZHI ZHAO MINGBO CHEN PING 《微计算机信息》 北大核心 2007年第34期70-72,85,共4页
Utilizing the technology of Ultrasonic wave,relevant test arithmetic and the PC to carry on monitoring,controlling and cen-tralized management of the liquid-level in the liquid container. It can prevent from keeping i... Utilizing the technology of Ultrasonic wave,relevant test arithmetic and the PC to carry on monitoring,controlling and cen-tralized management of the liquid-level in the liquid container. It can prevent from keeping in touch with the examined liquid,not only has increased the continuous working time of the system greatly,simplifying maintenance of the sensor conveniently,can also realize overhauling in producing and boost the productivity and management level. The working principle,hardware structure of the instrument and the design method are presented,and the selection of sensor and MCU is discussed in detail in this paper. MCU are used to control the emission and receiving. Then the liquid-level are calculated,which makes the design more intelligent. 展开更多
关键词 超声波传感器 液位监控 液位测量 温度补偿 MSP430 群罐
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Importance of Proficiency Testing in Water Quality Monitoring 被引量:2
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作者 郭正 向哲涛 宋华力 《Agricultural Science & Technology》 CAS 2014年第12期2201-2203,共3页
The monitoring data is undoubtedly important to the water quality monitor- ing department. The proficiency testing is an important way to improve the monitor- ing capacity and enhance the quality management of laborat... The monitoring data is undoubtedly important to the water quality monitor- ing department. The proficiency testing is an important way to improve the monitor- ing capacity and enhance the quality management of laboratories. It plays an impor- tant role in ensuring the accuracy, integrity and comparability of monitoring data. In this paper, the positive role of proficiency testing in the water quality monitoring was analyzed. In addition, how to improve the water quality monitoring capacity and the quality management level of laboratories through the proficiency testing was also discussed. 展开更多
关键词 Proficiency testing water quality monitoring Management level
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Monitoring models for base flow effect and daily variation of dam seepage elements considering time lag effect 被引量:11
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作者 Shao-wei Wang Ying-li Xu +1 位作者 Chong-shi Gu Teng-fei Bao 《Water Science and Engineering》 EI CAS CSCD 2018年第4期344-354,共11页
Affected by external environmental factors and evolution of dam performance, dam seepage behavior shows nonlinear time-varying characteristics. In this study, to predict and evaluate the long-term development trend an... Affected by external environmental factors and evolution of dam performance, dam seepage behavior shows nonlinear time-varying characteristics. In this study, to predict and evaluate the long-term development trend and short-term fluctuation of the dam seepage behavior, two monitoring models were developed, one for the base flow effect and one for daily variation of dam seepage elements. In the first model, to avoid the influence of the time lag effect on the evaluation of seepage variation with the time effect component of seepage elements, the base values of the seepage element and the reservoir water level were extracted using the wavelet multi-resolution analysis method, and the time effect component was separated by the established base flow effect monitoring model. For the development of the daily variation monitoring model for dam seepage elements, all the previous factors, of which the measured time series prior to the dam seepage element monitoring time may have certain influence on the monitored results, were considered. Those factors that were positively correlated with the analyzed seepage element were initially considered to be the support vector machine(SVM) model input factors, and then the SVM kernel function-based sensitivity analysis was performed to optimize the input factor set and establish the optimized daily variation SVM model. The efficiency and rationality of the two models were verified by case studies of the water level of two piezometric tubes buried under the slope of a concrete gravity dam.Sensitivity analysis of the optimized SVM model shows that the influences of the daily variation of the upstream reservoir water level and rainfall on the daily variation of piezometric tube water level are processes subject to normal distribution. 展开更多
关键词 Dam seepage monitoring model Time lag effect Support vector machine(SVM) Sensitivity analysis Base flow Daily variation Piezometric tube water level
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Image-based Water Level Measurement Method under Stained Ruler 被引量:5
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作者 Jae-do KIM Young-joon HAN Hern-soo HAHN 《Journal of Measurement Science and Instrumentation》 CAS 2010年第1期28-31,共4页
This paper propoes the water level measuring method based on the image, while the ruler used to indicate the water level is stained. The contamination of the ruler weakens or eliminates many features which are require... This paper propoes the water level measuring method based on the image, while the ruler used to indicate the water level is stained. The contamination of the ruler weakens or eliminates many features which are required for the image processing. However, the feature of the color difference between the ruler and the water surface are firmer on the environmental change compare to the other features. As the color differeaces are embossed, only the region of the ruler is limited to eliminate the noise, and the average image is produced by using several continuous frames. A histogram is then produced on the height axis of the produced intensity average image. Local peaks and local valleys are detected, and the section between the peak and valley which have the greatest change is looked for. The valley point at this very moment is used to detect the water level. The detected water level is then converted to the actual water level by using the mapping table. The proposed method is compared to the ultrasonic based method to evaluate its accuracy and efficiency on the various contaminated environments. 展开更多
关键词 water level measurment image processing surveillancesystem histogram analysis
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Determination of gross α and β activities in Zouma River based on online HPGe gamma measurement system 被引量:3
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作者 Xian Guan Liang-Quan Ge +3 位作者 Guo-Qiang Zeng Xiao-Qin Deng Li-Peng Xu Sheng-Liang Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2020年第12期65-76,共12页
This paper describes a low-cost and fast method to evaluate gross α and β^(-) radioactivities in natural water based on an online high-purity germanium detector gamma measurement system.The major gamma activities in... This paper describes a low-cost and fast method to evaluate gross α and β^(-) radioactivities in natural water based on an online high-purity germanium detector gamma measurement system.The major gamma activities in natural water are provided by natural and artificial radionuclides such as ^(40) K,^(137)Cs,and radionuclides belonging to ^(238)U and ^(232)Th series.The main a emitters related to gamma emissions in natural water are ^(224)Ra(240.98 keV)and ^(226)Ra(186.21 keV),and the β^(-) emitters are ^(40) K(1460.85 keV),^(214)Bi(609.31 keV),^(208)Tl(583.19 keV),and ^(214)Pb(351.93 keV).The formula for gross α and β^(-) activity concentration is based on these radionuclides,and the short half-life decay products are considered in the calculation.The detection efficiency of the device across energy region(0–3 MeV)is obtained through Monte Carlo simulation,and a calibration experiment is conducted to verify the simulation results.Gamma radioactivity is measured continuously for 114 d in Pixian County and Dongfeng Canal located in the Zouma River,Chengdu,Sichuan Province,China.A comparison of the calculation results and monitoring data from the Sichuan Management and Monitoring Center Station of Radioactive Environment indicates that the percentage and absolute error of a activity concentration is lower than 53%and 0.02 Bq/L,respectively,and that of β-activity concentration is lower than 33.2%and 0.016 Bq/L,respectively.The method can rapidly determine gross α and β^(-) activity concentrations in natural water online. 展开更多
关键词 Grossαandβ^(-)activity HPGe gamma spectrometer Online radioactivity level measurement for natural water Natural radioactivity water sources of Chengdu
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Geodynamic hazards and risk assessment at the Karachaganak oil,gas,and condensate field
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作者 A.Аbetov S.Kudaibergenova 《Geodesy and Geodynamics》 CSCD 2023年第1期80-89,共10页
The geodynamic hazards and risk assessment at the Karachaganak oil,gas,and condensate field(KOGCF)were explored on the northern board of the Pre-Caspian Basin to predict the consequences of the longterm exploitation o... The geodynamic hazards and risk assessment at the Karachaganak oil,gas,and condensate field(KOGCF)were explored on the northern board of the Pre-Caspian Basin to predict the consequences of the longterm exploitation of this field.We integrate multiple measurements,including repeated accurate leveling,Global Positioning System(GPS)measurements,and high precision gravimetric and seismological monitoring at the KOGCF.The results of geodynamic monitoring at the KOGCF for the first time made it possible to prove noticeable seismic deformation processes in the sedimentary cover under the influence of hydrocarbon production.The vertical displacements and horizontal movement along faults,changes in local gravity anomalies,and earthquake sources at depths comparable to hydrocarbon production intervals at the KOGCF have been identified.The maximum amplitudes of modern vertical movement of the earth’s surface and the minimum values of the differently oriented horizontal movement were revealed within the projection on the ground surface of the crest of the carbonate massif(Upper Devonian-Lower Permian age).The results suggest the expansion of uneven compression in the crest of the KOGCF while tension processes occur on its periphery.There is a decrease in gravity variations in relation to the slopes of this massif in areas with active hydrocarbon production.An extended zone of high-gradient steps of AGa anomalies,spatially coinciding with the position of fault zones,is mapped along the periphery of the contour of production wells.In the northeastern part of the KOGCF,seismic events were registered practically in the depth intervals of the productive horizons from which hydrocarbons are produced.A spatial relationship between the seismic events and the anomalous deformation activity in the northeast KOGCF has been revealed.Consequently,the field development has provoked both intense deformation of the earth’s surface and weak local seismicity. 展开更多
关键词 Geodynamic monitoring High precision gravimetric GPS measurements Repeat accurate leveling Seismological observation
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Evaluation of the treatment effect of rear slope cutting on hydrodynamic pressure landslides:A case study
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作者 WANG Li HUANG Jun-jie +4 位作者 CHEN Yong WANG Shi-mei FAN Zhi-hong GUO Fei LI Xiao-wei 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1968-1983,共16页
After the impoundment of the Three Gorges Reservoir,some huge ancient landslides were reactivated and deformed,showing typical hydrodynamic pressure landslide characteristics.The Baishuihe landslide was a typical hydr... After the impoundment of the Three Gorges Reservoir,some huge ancient landslides were reactivated and deformed,showing typical hydrodynamic pressure landslide characteristics.The Baishuihe landslide was a typical hydrodynamic pressure landslide.The management department conducted slope cutting treatments from 2018 to 2019.To evaluate the treatment effect of rear slope cutting,this study analyzed the data of the surface deformation survey and field monitoring over the past 20 years and the characteristics of the reservoir water-triggered Baishuihe landslide deformation,and calculated the seepage field,displacement field,and stability coefficient before and after landslide treatment.The results showed that the deformation of the Baishuihe landslide was primarily related to a decrease in the reservoir water level.Owing to the poor permeability of the landslide soil,the decrease in the reservoir water level produced a seepage force pointing to the outside of the landslide body,leading to the step deformation of the landslide displacement.The landslide was treated by rear slope cutting,and the“step”deformation of the landslide disappeared after treatment.The hydrodynamic pressure caused by the change in reservoir water after cutting the slope did not disappear.However,as the slope cutting greatly reduced the overall sliding force of the landslide,its stability was greatly improved.Notably,high stability can still be ensured under extreme rainfall after treatment.Slope cutting is effective for treating hydrodynamic pressure landslides.This study can provide effective technical support for the treatment of reservoir landslides. 展开更多
关键词 Hydrodynamic pressure landslide Three Gorges Reservoir Slope cutting Load reduction Landslide monitoring Ancient landslides Reservoir water level fluctuation
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江苏省平原水网区河湖生态水位确定探索与实践 被引量:1
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作者 盖永伟 蒋咏 胡晓雨 《水资源开发与管理》 2024年第1期30-34,共5页
保障河湖生态流量,事关江河湖泊健康。本文在分析江苏平原水网区域特点的基础上,选择生态水位作为河湖生态流量的表征指标,根据水利部确定的江苏省26条全国生态流量保障重点河湖名录,科学选定控制断面,采用1990—2020年水文序列资料,选... 保障河湖生态流量,事关江河湖泊健康。本文在分析江苏平原水网区域特点的基础上,选择生态水位作为河湖生态流量的表征指标,根据水利部确定的江苏省26条全国生态流量保障重点河湖名录,科学选定控制断面,采用1990—2020年水文序列资料,选用Qp法分析计算90%、95%、99%保证率下的水位,同步对比分析近10年最枯月水位、最低通航保证水位,最终确定了26条河湖的生态水位。通过制定保障措施方案、开展监测预警评估、强化统一调度管理等措施,全面保障区域河湖生态水位,为平原水网地区河湖生态水位的确定与保障提供了经验。 展开更多
关键词 河湖生态水位 保障措施 监测 管控 江苏省
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关于加强水库大坝下游水位监测的认识与建议 被引量:1
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作者 江超 吴全荣 +1 位作者 曹昕 闵国琪 《中国水利》 2024年第2期56-60,共5页
下游水位监测是1级~5级水库大坝必设的安全监测项目,但在实际建设过程中常常被忽视或误解,不利于充分发挥监测系统作用。通过设置下游水位监测,可以确定准确完整的坝体浸润线位置,支撑智慧水利建设;定量分析监测断面的防渗效果与渗流安... 下游水位监测是1级~5级水库大坝必设的安全监测项目,但在实际建设过程中常常被忽视或误解,不利于充分发挥监测系统作用。通过设置下游水位监测,可以确定准确完整的坝体浸润线位置,支撑智慧水利建设;定量分析监测断面的防渗效果与渗流安全性态,提高渗流安全监测资料分析深度;为大坝渗流计算提供可靠的重要边界条件参数,提升渗流计算成果可靠性与准确性。下游水位监测对大坝安全监测以及大坝安全管理至关重要,建议有条件的水库补充设置下游水位监测,进一步完善大坝安全监测系统。 展开更多
关键词 水库 大坝 安全监测 下游水位
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GNSS拟合高程代替水准测量的可行性分析:以黄河上游水电基地区域为例
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作者 杨会臣 贾金生 +4 位作者 郑璀莹 武志刚 赵志华 何欣 赵春 《水利水电技术(中英文)》 北大核心 2024年第S01期340-345,共6页
GNSS拟合高程代替水准测量有重要的现实意义,有必要对其进行可行性分析。黄河上游水电基地是中国在黄河上游地区开发的重要水利工程群,其安全监测具有至关重要的作用。因此,本文基于黄河上游水电基地GNSS自动监测网开展实验,从GNSS高程... GNSS拟合高程代替水准测量有重要的现实意义,有必要对其进行可行性分析。黄河上游水电基地是中国在黄河上游地区开发的重要水利工程群,其安全监测具有至关重要的作用。因此,本文基于黄河上游水电基地GNSS自动监测网开展实验,从GNSS高程拟合方法、GNSS数据处理策略和GNSS高程方向定位结果等方面详细论证。结果表明,GNSS拟合高程具有替代三等水准的可行性。 展开更多
关键词 GNSS 水准测量 变形监测
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网络球型摄像机瞬时视场的单点校正水位连续测量方法
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作者 刘科利 赵雪莹 +2 位作者 辛成章 刘昌军 姚吉利 《测绘通报》 CSCD 北大核心 2024年第10期120-124,173,共6页
基于网络球型摄像机进行洪水监测成为当今水利建设的热点之一,摄像机需进行旋转、焦距的放大与缩小等操作,才能在多视场进行流速、水位、流量一体化监测。由于摄像机传动装置制造的缺陷,在多视场切换时会出现预置点不能准确复位的问题... 基于网络球型摄像机进行洪水监测成为当今水利建设的热点之一,摄像机需进行旋转、焦距的放大与缩小等操作,才能在多视场进行流速、水位、流量一体化监测。由于摄像机传动装置制造的缺陷,在多视场切换时会出现预置点不能准确复位的问题而产生隙动差,这给从单张影像上解析水位、流速造成较大偏差,因此本文提出一种针对水位测量的隙动差校正方法。首先对预置点的水位尺进行精确标定,得到预置点水位方程参数,并在影像上选取两个特征明显的校正点;然后在连续监测中,将瞬时视场内校正点影像坐标按线性方法校正到预置点视场校正点;最后用预置点水位方程参数计算瞬时视场水位。经现场试验测试,不同瞬时视场校正点的影像坐标最大有8像素隙动差,产生水位误差达5 cm,而经本文方法计算的水位误差约为5 mm,说明本文方法对消减隙动差的影响是显著的。 展开更多
关键词 洪水监测 隙动差 线性校正 水位方程 水位精度
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降雨和库水位变动联合作用下滑坡位移加权反分析及监测预警方法
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作者 袁维 籍晓蕾 +9 位作者 王东坡 管凯歌 裴子豪 钟辉亚 唐佳 孙瑞峰 王伟 郑贺民 郭帅杰 李红旭 《测绘学报》 EI CSCD 北大核心 2024年第5期917-932,共16页
降雨和库水位变动是诱发大型库岸滑坡体持续变形甚至失稳的主要外在因素。针对以上两种因素联合作用下滑坡体的变形特征,本文提出一种基于多源数据的“反演-评估-融合-预警”四步式滑坡监测预警方法。该方法采用趋势项位移进行力学参数... 降雨和库水位变动是诱发大型库岸滑坡体持续变形甚至失稳的主要外在因素。针对以上两种因素联合作用下滑坡体的变形特征,本文提出一种基于多源数据的“反演-评估-融合-预警”四步式滑坡监测预警方法。该方法采用趋势项位移进行力学参数反演,有效避免了降雨、库水位变动等外在因素对反演结果的影响。同时,采用熵权值构建了反演目标函数,借此考虑了不同位置监测点对反演结果的影响程度。此外,考虑了滑坡体自身的地质条件和坡体结构对监测预警的影响,综合运用安全系数和综合变形速率构建了具有地质和力学基础的预警模型。采用本文方法对贵州三板溪水电站东岭信滑坡体进行了力学参数反演和监测预警,结果表明:该滑坡体整个监测期间的安全系数在1.25~1.70之间波动,整体状态呈下降趋势,基于安全系数的角度判断其尚处于稳定状态;综合变形速率呈现上、下波动趋势,与安全系数在变化规律上具有高度的相关性,两者可以从整体上表征该滑坡体在降雨和库水位变动联合作用下稳定性的演进过程;当前监测时刻点的综合变形速率是0.0599,根据分级预警模型判断此滑坡体当前处于稳定变形阶段(Ⅰ级预警),与安全系数的判断结果具有一致性。 展开更多
关键词 滑坡体 监测预警 参数反演 降雨 库水位变动
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雅鲁藏布江大拐弯地区河流水位日变化时空分异特征
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作者 余国安 岳蓬胜 侯伟鹏 《水科学进展》 EI CAS CSCD 北大核心 2024年第2期274-288,共15页
径流(或水位)日变化是反映河流水文情势的重要方面,解析径流(水位)日变化特征有助于明晰河流水文动态过程和规律,揭示径流来源和产汇流机制。以藏东南雅鲁藏布江大拐弯地区的易贡藏布、帕隆藏布、曲宗藏布、拉月曲、金珠曲和白马西路河... 径流(或水位)日变化是反映河流水文情势的重要方面,解析径流(水位)日变化特征有助于明晰河流水文动态过程和规律,揭示径流来源和产汇流机制。以藏东南雅鲁藏布江大拐弯地区的易贡藏布、帕隆藏布、曲宗藏布、拉月曲、金珠曲和白马西路河为对象,基于典型河段2022—2023年小时分辨率实测水位数据,采用数理统计和表征参数分析河流水位日变化时空分异特征,并结合降雨、冰川/积雪数据探究河流水位日变化影响因素。结果表明:研究区河流水位日变幅在汛期多高于非汛期,日水位数据分布在汛期多呈正偏(均值大于中值),汛后多呈负偏(均值小于中值);除白马西路河外,各河段水位日涨落过程在非汛期相对于汛期有所延迟,且汛后延迟趋势更明显;汛期各河段日水位上涨历时均小于回落历时,非汛期则多相反(拉月曲和金珠曲除外);白马西路河水位日变化主要受降雨过程扰动,而其他河流水位日变化主要受冰雪消融过程影响。 展开更多
关键词 水位日变化 实测水位 时空分异 影响因素 雅鲁藏布江
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宿迁市河流生态水位管控目标与预警机制分析
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作者 叶文 方红远 +3 位作者 黄金柏 邱福琼 樊浦 程倩倩 《江苏水利》 2024年第2期63-66,共4页
针对宿迁市近年水环境保护与水生态修复实践,阐述了宿迁市开展的第一批及相关重要河道生态水位制定情况与实施政策,分析了河道生态水位管理的工程调度原则与预警机制方案设计等技术内容,提出了河道生态水位管控目标保障措施。相关技术... 针对宿迁市近年水环境保护与水生态修复实践,阐述了宿迁市开展的第一批及相关重要河道生态水位制定情况与实施政策,分析了河道生态水位管理的工程调度原则与预警机制方案设计等技术内容,提出了河道生态水位管控目标保障措施。相关技术方法对构建完善的生态水位目标管控长效机制,提升宿迁市河湖水生态环境质量具有重要决策参考价值。 展开更多
关键词 河流生态水位 生态水位计算法 目标管控 预警机制 保障措施
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基于深度学习的双目视觉水位监测方法
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作者 孙秀峰 张从联 +1 位作者 李晓莅 阳剑峰 《广东水利水电》 2024年第9期43-47,53,共6页
利用双目相机采集3D点云数据,通过多次连续测量不断增补水面空间数据;利用基于Transformer架构的深度学习模型过滤弱化噪点,强化特征纹理,通过对点云数据进行加权处理得到监测水位,该方法无需安装标尺和现场标定,不需额外结构光发射装置... 利用双目相机采集3D点云数据,通过多次连续测量不断增补水面空间数据;利用基于Transformer架构的深度学习模型过滤弱化噪点,强化特征纹理,通过对点云数据进行加权处理得到监测水位,该方法无需安装标尺和现场标定,不需额外结构光发射装置,减少了场景限制,降低了功耗和成本。试验结果表明,该方法可以消除水面波纹和漂浮物等的干扰,水位监测最大误差为0.8 cm,系统不确定度、随机不确定度、综合不确定度指标均小于1 cm,可满足智慧水利感知网部署场景复杂的要求。 展开更多
关键词 深度学习 Transformer模型 双目视觉 水位监测
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GNSS-R水位监测研究进展与其在我国水利行业应用展望 被引量:1
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作者 张朋杰 庞治国 +3 位作者 路京选 江威 吕娟 孙铭涵 《全球定位系统》 CSCD 2024年第1期34-44,共11页
水位监测在水文学、水利工程、灾害防治等领域都具有非常重要的意义.传统的水位监测方法存在成本高、覆盖范围小等缺点,GNSS不仅具有导航、定位及授时的功能,还可以利用其反射信号获取反射面的特性信息并将其称为全球卫星导航系统反射测... 水位监测在水文学、水利工程、灾害防治等领域都具有非常重要的意义.传统的水位监测方法存在成本高、覆盖范围小等缺点,GNSS不仅具有导航、定位及授时的功能,还可以利用其反射信号获取反射面的特性信息并将其称为全球卫星导航系统反射测量(Global Navigation Satellite System-Reflectometry,GNSS-R).近年来,GNSS-R技术以低成本、全天候、高时空分辨率等优势为水位监测提供了一种新方法.本文对GNSS-R水位监测的研究现状、不同方法的影响因素以及当前应用过程中存在的问题进行了总结归纳提出了下一步的发展趋势,最后对其在我国水利行业的应用进行了展望. 展开更多
关键词 全球卫星导航系统反射测量(GNSS-R) 水位监测 群延迟 载波相位 信噪比(SNR)
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污水管道水位流速检测装置设计 被引量:2
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作者 陈丽珠 顾博文 +2 位作者 景鹏飞 周明连 许淑惠 《实验技术与管理》 CAS 北大核心 2024年第1期186-192,共7页
在线实时监测市政污水管道内污水的水位和流速能帮助市政管理部门精准掌握污水流动情况,及时了解管道出现的问题,提高工作效率。该文依据绕流理论设计并制作了一种基于浮球的水位和流速检测装置,通过测量浮球随水位变化的相对位移实现... 在线实时监测市政污水管道内污水的水位和流速能帮助市政管理部门精准掌握污水流动情况,及时了解管道出现的问题,提高工作效率。该文依据绕流理论设计并制作了一种基于浮球的水位和流速检测装置,通过测量浮球随水位变化的相对位移实现水位测量;通过测量流体对浮球的推力实现流速测量。装置的GSM/GPRS模块接收水位和流速的检测数据并传输至远程监控端,实现远程在线监测。在明渠标准实验台对该检测装置的水位和流速测量值进行标定和精度实验,实验结果表明:测量水位的偏差在±3 mm内,误差不大于其满量程的0.5%;流速测量偏差值在±0.04m/s内,误差不大于其满量程的5%。将该检测装置安装在实际的污水管道内,对污水水位和流速进行了为期三个月的实验监测,检测值的远程传输结果符合预期。 展开更多
关键词 水位 流速 检测 在线监测 污水管网 实验 模拟
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