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Real-Time Monitoring of Meteorological Data at In-Situ GCW Remediation Sites
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作者 Qinghai Wu Xiaofeng Yang +2 位作者 Jun Liu Ruiqi Wang Quanyou Fu 《Journal of Geoscience and Environment Protection》 2024年第9期152-166,共15页
To optimize the self-organization network, self-adaptation, real-time monitoring, remote management capability, and equipment reuse level of the meteorological station supporting the portable groundwater circulation w... To optimize the self-organization network, self-adaptation, real-time monitoring, remote management capability, and equipment reuse level of the meteorological station supporting the portable groundwater circulation wells, and to provide real-time and effective technical services and environmental data support for groundwater remediation, a real-time monitoring system design of the meteorological station supporting the portable groundwater circulation wells based on the existing equipment is proposed. A variety of environmental element information is collected and transmitted to the embedded web server by the intelligent weather transmitter, and then processed by the algorithm and stored internally, displayed locally, and published on the web. The system monitoring algorithm and user interface are designed in the CNWSCADA development environment to realize real-time processing and analysis of environmental data and monitoring, control, management, and maintenance of the system status. The PLC-controlled photovoltaic power generating panels and lithium battery packs are in line with the concept of energy saving and emission reduction, and at the same time, as an emergency power supply to guarantee the safety of equipment and data when the utility power fails to meet the requirements. The experiment proves that the system has the characteristics of remote control, real-time interaction, simple station deployment, reliable operation, convenient maintenance, and green environment protection, which is conducive to improving the comprehensive utilization efficiency of various types of environmental information and providing reliable data support, theoretical basis and guidance suggestions for the research of groundwater remediation technology and its disciplines, and the research and development of the movable groundwater cycling well monitoring system. 展开更多
关键词 Groundwater Circulation Well Weather Station real-time monitoring Embedded Web Server
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Fiber optic monitoring of an anti-slide pile in a retrogressive landslide 被引量:3
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作者 Lei Zhang Honghu Zhu +1 位作者 Heming Han Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期333-343,共11页
Anti-slide piles are one of the most important reinforcement structures against landslides,and evalu-ating the working conditions is of great significance for landslide mitigation.The widely adopted analytical methods... Anti-slide piles are one of the most important reinforcement structures against landslides,and evalu-ating the working conditions is of great significance for landslide mitigation.The widely adopted analytical methods of pile internal forces include cantilever beam method and elastic foundation beam method.However,due to many assumptions involved in calculation,the analytical models cannot be fully applicable to complex site situations,e.g.landslides with multi-sliding surfaces and pile-soil interface separation as discussed herein.In view of this,the combination of distributed fiber optic sensing(DFOS)and strain-internal force conversion methods was proposed to evaluate the working conditions of an anti-sliding pile in a typical retrogressive landslide in the Three Gorges reservoir area,China.Brillouin optical time domain reflectometry(BOTDR)was utilized to monitor the strain distri-bution along the pile.Next,by analyzing the relative deformation between the pile and its adjacent inclinometer,the pile-soil interface separation was profiled.Finally,the internal forces of the anti-slide pile were derived based on the strain-internal force conversion method.According to the ratio of calculated internal forces to the design values,the working conditions of the anti-slide pile could be evaluated.The results demonstrated that the proposed method could reveal the deformation pattern of the anti-slide pile system,and can quantitatively evaluate its working conditions. 展开更多
关键词 Anti-slide pile Multi-sliding surface Pile-soil interface Brillouin optical time domain reflectometry (BOTDR) Geotechnical monitoring Reservoir landslide
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基于病菌孢子捕捉和real-time PCR技术的田间空气中小麦白粉病菌孢子动态监测及病情估计模型研究
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作者 王奥霖 商昭月 +8 位作者 张美惠 王贵 胡小平 徐飞 孙振宇 曹世勤 刘伟 范洁茹 周益林 《植物保护》 CAS CSCD 北大核心 2024年第2期49-56,72,共9页
利用Burkard定容式孢子捕捉器结合real-time PCR定量技术,分别对种植高抗、中感和高感白粉病小麦品种的田间空气中白粉病菌分生孢子浓度进行监测,结果表明,real-time PCR定量与传统的显微观察计数两种方法测得的孢子浓度呈显著正相关(P... 利用Burkard定容式孢子捕捉器结合real-time PCR定量技术,分别对种植高抗、中感和高感白粉病小麦品种的田间空气中白粉病菌分生孢子浓度进行监测,结果表明,real-time PCR定量与传统的显微观察计数两种方法测得的孢子浓度呈显著正相关(P≤0.01),且两种病菌孢子计数方法在同一抗性品种上监测到的孢子浓度动态相近。此外,两种方法测得的孢子浓度与各气象因子的相关性分析结果一致,空气中的白粉病菌孢子浓度主要与空气相对湿度显著正相关。在此基础上,利用两种方法测定的田间空气中白粉病菌孢子浓度分别建立了基于累积孢子浓度的田间病情估计模型。分析发现,基于两种孢子浓度测定方法建立的病情估计模型间无显著性差异,表明real-time PCR定量技术测定的孢子浓度在构建白粉病病情估计模型上具有一定可行性。该结果为real-time PCR定量技术与病菌孢子捕捉技术相结合用于小麦白粉病的监测和预测提供理论依据。 展开更多
关键词 小麦白粉病 病菌孢子捕捉 实时荧光定量PCR 病原菌监测 病情估计模型
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Deformation monitoring of long-span railway bridges based on SBAS-InSAR technology
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作者 Lv Zhou Xinyi Li +4 位作者 Yuanjin Pan Jun Ma Cheng Wang Anping Shi Yukai Chen 《Geodesy and Geodynamics》 EI CSCD 2024年第2期122-132,共11页
The deformation monitoring of long-span railway bridges is significant to ensure the safety of human life and property.The interferometric synthetic aperture radar(In SAR)technology has the advantage of high accuracy ... The deformation monitoring of long-span railway bridges is significant to ensure the safety of human life and property.The interferometric synthetic aperture radar(In SAR)technology has the advantage of high accuracy in bridge deformation monitoring.This study monitored the deformation of the Ganjiang Super Bridge based on the small baseline subsets(SBAS)In SAR technology and Sentinel-1A data.We analyzed the deformation results combined with bridge structure,temperature,and riverbed sediment scouring.The results are as follows:(1)The Ganjiang Super Bridge area is stable overall,with deformation rates ranging from-15.6 mm/yr to 10.7 mm/yr(2)The settlement of the Ganjiang Super Bridge deck gradually increases from the bridge tower toward the main span,which conforms to the typical deformation pattern of a cable-stayed bridge.(3)The sediment scouring from the riverbed cause the serious settlement on the bridge’s east side compared with that on the west side.(4)The bridge deformation negatively correlates with temperature,with a faster settlement at a higher temperature and a slow rebound trend at a lower temperature.The study findings can provide scientific data support for the health monitoring of long-span railway bridges. 展开更多
关键词 SBAS-InSAR Long-span railway bridge Deformation monitoring Bridge structure time series deformation
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A Remote Real-Time Monitoring System for Power Quality 被引量:1
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作者 黄治清 贺建闽 《Journal of Southwest Jiaotong University(English Edition)》 2003年第1期31-38,共8页
An introduction is made to the composition, design method and engineering application of a remote real time monitoring system of power quality in substations based on internet. With virtual instrument and network tec... An introduction is made to the composition, design method and engineering application of a remote real time monitoring system of power quality in substations based on internet. With virtual instrument and network technique adopted, this system is characterized by good real time property, high reliability, plentiful functions, and so on. It also can be used to monitor the load of a substation, such as electric locomotives. 展开更多
关键词 power quality remote monitoring real time monitoring system virtual instrument
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Real-time State Monitoring During Switching Mode Transitions in High Power Three-level Inverters 被引量:9
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作者 HE Xiangning WU Yansong +2 位作者 YANG Bingjian WANG Jun DENG Yan 《中国电机工程学报》 EI CSCD 北大核心 2012年第30期I0008-I0008,10,共1页
大功率多电平逆变器近年来在实际工业生产中得到越来越广泛的应用。多电平逆变器由于结构复杂,采用元器件较多,因此在设计和实验中,实现各个工作状态下运行参数的同步监测和分析较为困难。本文针对大功率三电平逆变器,实现开关动态特性... 大功率多电平逆变器近年来在实际工业生产中得到越来越广泛的应用。多电平逆变器由于结构复杂,采用元器件较多,因此在设计和实验中,实现各个工作状态下运行参数的同步监测和分析较为困难。本文针对大功率三电平逆变器,实现开关动态特性的在线测试,在此基础上,进一步研究三电平逆变器在开关状态变化时理论与实际负载运行工况下电路拓扑的转换变化规律。通过全电路电气参数和元器件状态的实时监测,发现在三电平逆变器非正常运行状态下开关转换时额外电应力,同时,深入研究在实际工况运行条件非正常状态下该额外电应力出现的机理和原因,为三电平逆变器的故障诊断提供了参考,对于设计高可靠性的多电平逆变器系统有一定的理论和现实意义。 展开更多
关键词 实时状态监测 三电平逆变器 模式转换 大功率 多电平逆变器 开关 拓扑结构 高功率
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A Novel Method for Real-Time Monitoring of Channel Siltation Based on Bistatic Scattering Theory
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作者 侯朋 许文海 +1 位作者 王俊生 李瑛 《China Ocean Engineering》 SCIE EI 2010年第1期105-115,共11页
Monitoring the thickness changes of channel siltation is paramount in safeguarding navigation and guiding dredging, This paper presents a novel method for realizing the field monitoring of channel siltation in real ti... Monitoring the thickness changes of channel siltation is paramount in safeguarding navigation and guiding dredging, This paper presents a novel method for realizing the field monitoring of channel siltation in real time. The method is based on the bistatic scattering theory and concerned more with the receiving and processing of multipath signal at high-frequency and small grazing angle. By use of the multipath propagation structure of underwater acoustic channel, the method obtains the silt thickness by calculating the relative time delay of acoustic signals between the direct and the shortest bottom reflected paths. Bistatic transducer pairs are employed to transmit and receive the acoustic signals, and the GPS time synchronization technology is introduced to synchronize the transmitter and receiver, The WRELAX (Weighted Fourier transforul and RELAX) algorithm is used to obtain the high resolution estimation of muhipath time delay. To examine the feasibility of the presented method and the accuracy and precision of the developed system, a series of sea trials are conducted in the southwest coast area of Dalian City, north of the Yellow Sea. The experimental results are compared with that using high-resolution dual echo sounder HydroBoxTM, and the uncertainty is smaller than + 0.06 m. Compared with the existing means for measuring the silt thickness, the present method is innovative, and the system is stable, efficient and provides a better real-time performance. It especially suits monitoring the narrow channel with rapid changes of siltation. 展开更多
关键词 channel siltation real-time monitoring bistatic bottom scattering relative time delay WREIAX multipath signal
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The Improvement of Earthquake Real-Time Monitoring System of Chinese National Digital Seismic Network 被引量:3
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作者 GUO Tielong HUANG Zhibin ZHAO Bo 《Earthquake Research in China》 CSCD 2019年第4期596-604,共9页
The earthquake real-time monitoring system of the Chinese National Digital Seismic Network has been in operation since"the Ninth Five-year Plan"period,and the stability of the system has been well tested.In ... The earthquake real-time monitoring system of the Chinese National Digital Seismic Network has been in operation since"the Ninth Five-year Plan"period,and the stability of the system has been well tested.In recent years,with the continuous improvement of monitoring technology and increase of public demands,the original real-time monitoring system needs to be upgraded and improved in terms of timeliness,stability,accuracy and ease of operation.Therefore,by accessing a total of more than 1,000 seismic stations,reducing the seismic trigger threshold of the monitoring system,eliminating the false trigger stations and optimizing the seismic waveform display interface,the current earthquake monitoring demands can be satisfied on the basis of ensuring the stable operation of the system. 展开更多
关键词 Seismic monitoring Earthquake location Computer real-time processing
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Real-Time Monitoring of Climactic and Geotechnical Variables during Landslides on the Slopes of Serra do Mar and Serra da Mantiqueira (S&atilde;o Paulo State, Brazil) 被引量:2
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作者 Rodolfo Moreda Mendes Mário Valé rio Filho 《Engineering(科研)》 2015年第3期140-159,共20页
The municipalities of Ubatuba, Campos do Jord?o, and S?o José dos Campos are located in the region of S?o Paulo State (Brazil). These municipalities are recognized nationally for having an elevated number of reco... The municipalities of Ubatuba, Campos do Jord?o, and S?o José dos Campos are located in the region of S?o Paulo State (Brazil). These municipalities are recognized nationally for having an elevated number of recorded landslides on slopes and embankments. In addition, these municipalities contain multiple areas that are at risk for landslides. Various soil landslides occurred in these municipalities in January 2013, when real-time climactic and geotechnical variables were monitored by automatic rain gauges, humidity sensors and soil temperature and suction devices. The resulting data were used to understand the functions of each variable in the occurrence of land- slides. Analyses of rainfall, humidity and soil temperature were used with field investigations to formulate a hypothesis regarding the predominant rupture mechanism and the role of each monitored variable in the deflagration of the soil landslides that occurred in the three studied municipalities. The geotechnical variable data revealed that both temperature and soil moisture contents played fundamental roles in the deflagration of shallow planar landslides in urban areas. The hourly rain intensity and/or rainfall accumulation for 24 and/or 72 h were responsible for the deflagration of the landslides that occurred in the studied areas, along with the existing anthropic constraints in the risk areas. Significant variations did not occur in the soil suction data during the landslides, principally due to the unsatisfactory sensor precision when reading field suction between –10 and?–100 kPA (±25%). 展开更多
关键词 LANDSLIDES Urban Area real-time monitoring Analysis of RAINFALL and GEOTECHNICAL Parameters
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Real-time Monitoring of Subsea Gas Pipelines,Offshore Platforms,and Ship Inspection Scores Using an Automatic Identification System 被引量:1
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作者 K.B.Artana T.Pitana +3 位作者 D.P.Dinariyana M.Ariana D.Kristianto E.Pratiwi 《Journal of Marine Science and Application》 CSCD 2018年第1期101-111,共11页
The aim of this research is to develop an algorithm and application that can perform real-time monitoring of the safety operation of offshore platforms and subsea gas pipelines as well as determine the need for ship i... The aim of this research is to develop an algorithm and application that can perform real-time monitoring of the safety operation of offshore platforms and subsea gas pipelines as well as determine the need for ship inspection using data obtained from automatic identification system(AIS).The research also focuses on the integration of shipping database,AIS data,and others to develop a prototype for designing a real-time monitoring system of offshore platforms and pipelines.A simple concept is used in the development of this prototype,which is achieved by using an overlaying map that outlines the coordinates of the offshore platform and subsea gas pipeline with the ship’s coordinates(longitude/latitude)as detected by AIS.Using such information,we can then build an early warning system(EWS)relayed through short message service(SMS),email,or other means when the ship enters the restricted and exclusion zone of platforms and pipelines.The ship inspection system is developed by combining several attributes.Then,decision analysis software is employed to prioritize the vessel’s four attributes,including ship age,ship type,classification,and flag state.Results show that the EWS can increase the safety level of offshore platforms and pipelines,as well as the efficient use of patrol boats in monitoring the safety of the facilities.Meanwhile,ship inspection enables the port to prioritize the ship to be inspected in accordance with the priority ranking inspection score. 展开更多
关键词 Automatic identification system AIS real-timemonitoring Subsea gas pipeline OFFSHORE platform SHIP inspection SCORE
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A Real-time Monitoring System for Tire Blowout or Severe Leakage
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作者 陈庆樟 郭立书 杨雄 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第2期126-128,共3页
The tire blowout or severe leakage real-time monitoring is one of key technologies for developing a tire blowout automatic braking system.An indirect real-time monitoring method to fuse analyses of tire vibration and ... The tire blowout or severe leakage real-time monitoring is one of key technologies for developing a tire blowout automatic braking system.An indirect real-time monitoring method to fuse analyses of tire vibration and effective radius is provided in this paper,and a monitoring system is developed.The calibration and related test results showthat the system can detect the tire blowout in low and middle vehicle speeds and the severe leakage in all speeds timely and accurately. 展开更多
关键词 AUTOMOBILE tire blowout LEAKAGE real-time monitoring
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Real-time Monitoring of Nucleotide Excision of Molecular Beacon Catalyzed by Klenow Fragment
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作者 LIU Bin, YANG Xiao-hai, WANG Ke-min and TAN Wei-hong State Key Laboratory of Chemo/Biosensing and Chemometrics, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第1期37-40,共4页
Klenow fragment(KF) uses the activity of a separate exonuclease to excise nucleotide, which is a crucial step in DNA replication and repair. Here is a novel sensitive and convenient method introduced for real-time m... Klenow fragment(KF) uses the activity of a separate exonuclease to excise nucleotide, which is a crucial step in DNA replication and repair. Here is a novel sensitive and convenient method introduced for real-time monitoring nucleotide excision by KF with a molecular beacon as a detecting probe in a homogeneous solution. This method, which overcomes the drawbacks of traditional methods such as discontinuity, time consuming and low sensitivity, was used to assay KF activity and the detection limit reached up to 0.4 U/mL. In addition, the method was applied to investigating the effects of metal ions and chemical drugs on the reaction. The results demonstrate that it is a potential high-throughput assay for screening inhibitors and activity analysis of KF in vitro. 展开更多
关键词 real-time monitoring Klenow fragment Molecular beacon
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Alternate Data Acquisition and Real-time Monitoring System on HT-7 Tokamak
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作者 魏沛杰 罗家融 +1 位作者 王华 李贵明 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第6期3114-3116,共3页
A new system called alternate data acquisition and real-time monitoring system has been developed for long-time discharge in tokamak operation. It can support continuous on-line data acquisition at a high sampling rat... A new system called alternate data acquisition and real-time monitoring system has been developed for long-time discharge in tokamak operation. It can support continuous on-line data acquisition at a high sampling rate and a graphic display of the plasma parameters during the discharge. Thus operators can monitor and control the plasma state in real time. An application of this system has been demonstrated on the HT-7 tokamak. 展开更多
关键词 alternate data acquisition real-time monitoring TOKAMAK
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Remote real-time monitoring soil water potential system based on GSM
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作者 Yongming Zhao Xin Lu Haijiang Wang 《新疆农业科学》 CAS CSCD 2008年第A02期77-80,共4页
Aiming at the limitation of traditional measuring soil water potential, the paper presents an information system based GSM to real-time monitor data coming from multiple data sources. The monitoring system, which cons... Aiming at the limitation of traditional measuring soil water potential, the paper presents an information system based GSM to real-time monitor data coming from multiple data sources. The monitoring system, which consisted of monitoring center, GSM transmission channel and data detection terminal, was given. The detection terminal included the measuring station and TS-2 negative pressure meter, which was applied to measure soil water potential. Nowadays the system has been successfully applied to drip irrigation in the cotton field on farm in Xinjiang region. The system provides a feasible technology frame-work for collecting and processing wide geographical distribution data in farmland. 展开更多
关键词 土壤水势 实时监控系统 测量方法 种植技术
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Multi-parameter real-time monitoring scheme for power transmission lines based on FBG sensors
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作者 李鹏飞 《无线互联科技》 2014年第12期111-111,133,共2页
A multi-parameter real-time monitoring scheme for power transmission line is proposed and experimentally demonstrated.The Fiber Bragg Grating(FBG)sensors are used to sensing the information of temperature and strain i... A multi-parameter real-time monitoring scheme for power transmission line is proposed and experimentally demonstrated.The Fiber Bragg Grating(FBG)sensors are used to sensing the information of temperature and strain in the power transmission lines system,and a monitoring center based on client–server model is established to process and display the sensing information.Several FBG-based power transmission line temperature sensors interrogated based on the developed multi-parameter real-time monitoring scheme is experimentally investigated.The result shows that the system is very useful. 展开更多
关键词 无线技术 互联网 科技创新 信息产业
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Real-time monitoring of weld penetration quality in robotic arc welding process
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作者 武传松 贾传宝 段晓宁 《China Welding》 EI CAS 2008年第1期40-43,共4页
It is of great significance to develop an intelligent monitoring system for weld penetration defects such as incomplete penetration and burn-through in real-time during robotic arc welding process. In this paper, robo... It is of great significance to develop an intelligent monitoring system for weld penetration defects such as incomplete penetration and burn-through in real-time during robotic arc welding process. In this paper, robotic gas metal arc welding experiments are carried out on the mild steel test pieces with Vee-type groove. Through-the-arc sensing method is used to capture the transient values of the welding voltage and current. The raw data of the captured welding current and voltage are processed statistically, and the feature vector SIO is extracted to correlate the welding conditions to the weld penetration information. It lays foundation for intelligent monitoring of weld quality in robotic arc welding. 展开更多
关键词 real-time monitoring statistical processing weld penetration robotic arc welding
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Sensor placement of long-term health monitoring for large bridges based on the real-time correction of finite element model
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作者 陈悦 ZHOU Jian-ting SHEN Pei-wen 《Journal of Chongqing University》 CAS 2013年第3期123-130,共8页
The process of optimized placement of long-term health monitoring sensors for large bridges generally begins with finite element models, but there will arise great discrepancies between theoretically-calculated result... The process of optimized placement of long-term health monitoring sensors for large bridges generally begins with finite element models, but there will arise great discrepancies between theoretically-calculated results and actual measurements.Therefore, rectified finite element models need to be rectified by virtue of model rectifying technology. Firstly, the result of construction monitoring and finished state load test is used to real-time modification of finite element model. Subsequently, an accurate finite element model is established. Secondly, the optimizing the layout of sensor with following orthogonality guarantees orthogonal property and linear independence for the measured data. Lastly, the effectiveness and feasibility of method in the paper is tested by real-time modifying finite element model and optimizing the layout of sensor for Nujiang Bridge. 展开更多
关键词 large bridges health monitoring real-time correction optimal sensor placement
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Indoor Air Quality Real-Time Monitoring Results of Pathology Department
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作者 Like Shi Yue Wang +4 位作者 Liang Xu Yan Liu Dongsheng Yao Xiuwu Li Yuan Jia 《Journal of Environmental Protection》 2015年第8期851-856,共6页
In this work, the objectives were to provide a scientific basis for environmental governance and to ensure staff health by real-time monitoring of indoor air quality of the pathology department. Using eagle eye enviro... In this work, the objectives were to provide a scientific basis for environmental governance and to ensure staff health by real-time monitoring of indoor air quality of the pathology department. Using eagle eye environment monitor to make a real-time dynamic monitoring of the air quality of the pathological technical room for 30 days, the paper records the monitoring data of PM 2.5, PM 10, formaldehyde, CO2, total volatile organic compounds (TVOC) every day at Beijing time 3 a.m, 10 am, 1 pm, 4 pm, and 10 pm, and makes a summarization and analysis. The average value of CO2 concentration of the 5 time points is (0.05 ± 0.01)%, and each time point concentration are different (P 0.05);the average TVOC concentration of the 5 time points is (0.08 + 0.31) mg/m3. They are all different between the concentration at each time point (P 2 and NO are not checked out. Through the real-time online monitoring of the pathology room, we find that the formaldehyde concentration of different time periods is far more than the safety value standard, and the concentration of formaldehyde, CO2, PM 2.5, PM 10 and total volatile organic compound (TVOC) is different at different time periods, and the concentrations at working time are higher than the non-working time. We must take effective measures to control the concentration of harmful gases in order to ensure the staff’s health. 展开更多
关键词 PATHOLOGY DEPARTMENT INDOOR POLLUTION real-time monitoring Influence FACTORS
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Real-Time Air Monitoring of Trichloroethylene and Tetrachloroethylene Using Mobile TAGA Mass Spectrometry
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作者 Nicholas S. Karellas Qingfeng Chen 《Journal of Environmental Protection》 2013年第8期99-105,共7页
Trichloroethylene (TCE) is a chlorinated liquid that is commonly used for metal degreasing, household and industrial dry cleaning, and in paints and glues. Tetrachloroethylene, also known as perchloroethylene (PCE), i... Trichloroethylene (TCE) is a chlorinated liquid that is commonly used for metal degreasing, household and industrial dry cleaning, and in paints and glues. Tetrachloroethylene, also known as perchloroethylene (PCE), is an excellent solvent for organic materials. PCE is volatile, highly stable, non-flammable and widely used in dry cleaning. A new method has been developed for measuring TCE and PCE in ambient air in real-time. Based upon the chemical fingerprinting and concentration levels, the method was able to isolate the source of the emissions to the responsible facility. Real-time monitoring was accomplished by utilizing a low pressure chemical ionization source (LPCI) interfaced to a tandem mass spectrometer (TAGA). Monitoring the response of specific parent/daughter ion pairs, the TAGA was used to measure concentrations of TCE and PCE. By optimizing various TAGA parameters, detection limits (DL) as low as 0.5 μg/m3 was achieved for TCE and PCE. Unlike methods using cartridge sampling and GC/MS analysis, this new method provides a real time measurement for a wide range of TCE and PCE concentrations. This unique method was applied in 2000 and 2002 to measure TCE emitted from a manufacturer of stainless steel tubing in Eastern Ontario. The maximum half-hour average concentration of TCE measured downwind of the facility was 1300 μg/m3 and the maximum instantaneous level was measured at 115,000 μg/m3. The information collected by the TAGA unit was used by the Standard Development Branch of Ontario Ministry of the Environment to adopt the half-hour Point of Impingement (POI) standard of TCE to be 36 μg/m3 in 2010. This method successfully identified and simultaneously measured TCE and PCE during a 2011 air monitoring survey of a hazardous waste disposal and treatment facility in Southern Ontario. 展开更多
关键词 Environmental real-time monitoring MOBILE TAGA TCE and PCE Ambient Air
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Development and Application of Real-time Bridge Scour Monitoring System
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作者 Joongu Kang 《Engineering(科研)》 2011年第10期978-985,共8页
Because of the complex nature of the changes in the current and movement of the riverbeds by bridge scouring, it is impossible to understand or predict these changes. In order to have a reliable data, it is critical t... Because of the complex nature of the changes in the current and movement of the riverbeds by bridge scouring, it is impossible to understand or predict these changes. In order to have a reliable data, it is critical to have the current methods and equipment for measuring bridge scouring replaced with technology that could acquire real-time bridge scouring data. Despite the critical need for real-time data acquisition, the harsh environmental conditions have prevented the scientific community from acquiring real-time data. Harsh environmental conditions were addressed by the developmental of an automated, remote data collection system, allowing real-time data such as scour movement, scour depth, and scour trend to be viewed in a safe location. As a result, accurate sea-floor movements were seen for the first time, aiding the direction and future of bridge scour research, ultimately contributing greatly to the safety of bridges. 展开更多
关键词 BRIDGE SCOUR real-time DATA ACQUISITION monitoring System
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