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Characterizations of air pollutants at roadside monitoring stations and traffic emission effects:A case study in Tianjin,China
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作者 Fangyuan Zheng Junxia Gao +8 位作者 Lin Wu Naixiu Sun Wentian Xu Qijun Zhang Hongjun Mao Jianfei Peng Liwei Li Ning Yang Bin Liu 《Journal of Environmental Sciences》 2025年第11期592-604,共13页
To investigate the response of Roadside Monitoring Stations(RSs)to traffic-related air pollution,traffic and pollutant characteristics,influencing factors,and potential source characterization in Tianjin,China were de... To investigate the response of Roadside Monitoring Stations(RSs)to traffic-related air pollution,traffic and pollutant characteristics,influencing factors,and potential source characterization in Tianjin,China were determined based on roadside monitoring of real-world data conducted at RSs in 2022.The diurnal variation trend of pollutants at RSs was consistent with that at the National Monitoring Station(NM),with notably higher pollutant fluctuations during the morning and evening peak traffic times at RSs,where the average diurnal concentration was 41.46%higher than that at the NM.The generalized additive model(GAM)for nitrogen oxides(NO_(x))and carbon monoxide(CO),responding to themultiple influencing factors,performed well at RSs,with deviance explained by 86.6%and 61.4%,respectively.The synergistic effects of wind direction and speed contributed to most of the variations in NO_(x) and CO,which were 14.74%and 12.87%,respectively.Pollutant concentrations were highest under windless conditions,with pollutants originating primarily from local vehicle emissions.The model results indicated that medium-duty truck(MDT)traffic flow predominantly contributed to the variability in NO_(x) emissions,whereas passenger car(PC)traffic flow was the primary source of CO emissions from traffic variables.MDTs should be the focus of urban NO_(x) traffic emissions control.Potential-source analysis validated the results obtained from the GAM,and both analyses showed that RSs can better characterize traffic-related air pollutants.Furthermore,more stringent emission standards have effectively mitigated the release of pollutants from motor vehicles and contributed to the modernization of vehicle fleet composition,effectively decreasing CO concentrations. 展开更多
关键词 Roadside monitoring station Traffic emissions Spatiotemporal variation Traffic-related air pollutants Generalized additive model(GAM)
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Coupling Spectral Indices and Machine Learning to Compare GF-6 and Sentinel-2A Data in Forest Health Monitoring
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作者 CHEN Jiahui XU Hanqiu TANG Fei 《Chinese Geographical Science》 2025年第3期581-599,共19页
The red-edge bands and their derived vegetation indices play a crucial role in monitoring vegetation health.The Gaofen-6(GF-6)and Sentinel-2A satellites are equipped with two and three red-edge bands,respectively,thus... The red-edge bands and their derived vegetation indices play a crucial role in monitoring vegetation health.The Gaofen-6(GF-6)and Sentinel-2A satellites are equipped with two and three red-edge bands,respectively,thus making them invaluable for monit-oring forest health.To compare the performance of these two satellites’red-edge bands in monitoring forest health,this study selected forests in Liuyang City,Hunan Province and Tonggu County,Jiangxi Province and Hanzhong City,Shaanxi Province in China as study areas and used three commonly used red-edge indices and the Random Forest(RF)algorithm for the comparison.The three selected red-edge indices were the Normalized Difference Red-Edge Index 1(NDRE1),the Missouri emergency resource information system Ter-restrial Chlorophyll Index(MTCI),and the Inverted Red-Edge Chlorophyll Index(IRECI).Through training of sample regions,this study determined the spectral differences among three forest health levels and established classification criteria for these levels.The res-ults showed that GF-6 imagery provided higher accuracy in distinguishing forest health levels than Sentinel-2A,with an average accur-acy of 90.22%versus 76.55%.This difference is attributed to variations in the wavelengths used to construct the red-edge indices between GF-6 and Sentinel-2A.In the RF algorithm,this study employed three distinct band combinations for classification:all bands including red-edge bands,excluding red-edge bands,and only red-edge bands.The results indicated that GF-6 outperformed Sentinel-2A when using the first and second band combinations,yet slightly underperforming with the third.This outcome was closely associ-ated with the importance of each band’s contribution to classification accuracy reveled by the Gini importance score,their sensitivity in detecting forest health conditions,and the total number of bands employed in the classification process.Overall,the NDRE1 derived from GF-6 achieved the highest average accuracy(90.22%).This study provides a scientific basis for selecting appropriate remote sens-ing data and techniques for forest health monitoring,which is of significant importance for the future ecological protection of forests. 展开更多
关键词 remote sensing Gaofen-6(GF-6) Sentinel-2A red-edge index Random Forest(RF) forest health
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Extraction of gravel characteristics and spatial inversion for ecological restoration monitoring in the Northern Tibetan Plateau
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作者 KONG Bo YU Huan +3 位作者 QIU Xia HU Wenkai HE Bing GUAN Xudong 《Journal of Mountain Science》 2025年第2期556-574,共19页
Previous studies have often focused on monitoring grassland growth as the primary target of remote sensing investigations on grassland ecological restoration in the northern Tibetan Plateau,overlooking the crucial rol... Previous studies have often focused on monitoring grassland growth as the primary target of remote sensing investigations on grassland ecological restoration in the northern Tibetan Plateau,overlooking the crucial role played by gravel in the ecological restoration of these grasslands.This study utilizes supervised classification and segmentation techniques based on machine learning to extract gravel morphology profiles from field-sampled plot images and calculate their characteristic parameters.Employing a multivariate linear approach combined with Principal Component Analysis(PCA),a model for inferring gravel characteristic parameters is constructed.Statistical features,particle size characteristics,and spatial distribution patterns of gravel are analyzed.Results reveal that gravel predominantly exhibit sub-rounded shapes,with 80%classified as fine gravel.The coefficients of determination(R2)between gravel particle size and coverage,perimeter,and area are 0.444,0.724,and 0.557,respectively,indicating linear relationships.The cumulative contribution rate of the top five remote sensing factors is 95.44%,with the first geological factor contributing 77.64%,collectively reflecting the primary information of the 20 factors used.Modeling shows that areas with larger gravel particle sizes correspond to increased perimeter and coverage.Gravels in the Nagqu Prefecture of northern Xizang have a particle size range of 4-8 mm,primarily comprising fine gravel which accounts for 94.61%.These findings provide a scientific basis for extracting gravel characteristic parameters and understanding their spatial distribution variations in the northern Tibetan Plateau. 展开更多
关键词 Gravel characteristics parameters Northern Tibetan Plateau Gravel outline extraction Remote sensing inversion Grassland degradation
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Research on High-Velocity Impact Damage Monitoring Method of CFRP Based on Guided Wave 被引量:1
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作者 WANG Yang YANG Xiaofei +1 位作者 QIU Lei YUAN Shenfang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期60-69,共10页
Carbon fiber-reinforced polymer(CFRP)is widely used in aerospace applications.This kind of material may face the threat of high-velocity impact in the process of dedicated service,and the relevant research mainly cons... Carbon fiber-reinforced polymer(CFRP)is widely used in aerospace applications.This kind of material may face the threat of high-velocity impact in the process of dedicated service,and the relevant research mainly considers the impact resistance of the material,and lacks the high-velocity impact damage monitoring research of CFRP.To solve this problem,a real high-velocity impact damage experiment and structural health monitoring(SHM)method of CFRP plate based on piezoelectric guided wave is proposed.The results show that CFRP has obvious perforation damage and fiber breakage when high-velocity impact occurs.It is also proved that guided wave SHM technology can be effectively used in the monitoring of such damage,and the damage can be reflected by quantifying the signal changes and damage index(DI).It provides a reference for further research on guided wave structure monitoring of high/hyper-velocity impact damage of CFRP. 展开更多
关键词 guided waves structural health monitoring(SHM) carbon fiber reinforced polymer(CFRP) high-velocity impact
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Panoptic UAV:Panoptic Segmentation of UAV Images for Marine Environment Monitoring 被引量:1
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作者 Yuling Dou Fengqin Yao +7 位作者 Xiandong Wang Liang Qu Long Chen Zhiwei Xu Laihui Ding Leon Bevan Bullock Guoqiang Zhong Shengke Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期1001-1014,共14页
UAV marine monitoring plays an essential role in marine environmental protection because of its flexibility and convenience,low cost and convenient maintenance.In marine environmental monitoring,the similarity between... UAV marine monitoring plays an essential role in marine environmental protection because of its flexibility and convenience,low cost and convenient maintenance.In marine environmental monitoring,the similarity between objects such as oil spill and sea surface,Spartina alterniflora and algae is high,and the effect of the general segmentation algorithm is poor,which brings new challenges to the segmentation of UAV marine images.Panoramic segmentation can do object detection and semantic segmentation at the same time,which can well solve the polymorphism problem of objects in UAV ocean images.Currently,there are few studies on UAV marine image recognition with panoptic segmentation.In addition,there are no publicly available panoptic segmentation datasets for UAV images.In this work,we collect and annotate UAV images to form a panoptic segmentation UAV dataset named UAV-OUC-SEG and propose a panoptic segmentation method named PanopticUAV.First,to deal with the large intraclass variability in scale,deformable convolution and CBAM attention mechanism are employed in the backbone to obtain more accurate features.Second,due to the complexity and diversity of marine images,boundary masks by the Laplacian operator equation from the ground truth are merged into feature maps to improve boundary segmentation precision.Experiments demonstrate the advantages of PanopticUAV beyond the most other advanced approaches on the UAV-OUC-SEG dataset. 展开更多
关键词 Panoptic segmentation UAV marine monitoring attention mechanism boundary mask enhancement
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Short-term displacement prediction for newly established monitoring slopes based on transfer learning
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作者 Yuan Tian Yang-landuo Deng +3 位作者 Ming-zhi Zhang Xiao Pang Rui-ping Ma Jian-xue Zhang 《China Geology》 CAS CSCD 2024年第2期351-364,共14页
This study makes a significant progress in addressing the challenges of short-term slope displacement prediction in the Universal Landslide Monitoring Program,an unprecedented disaster mitigation program in China,wher... This study makes a significant progress in addressing the challenges of short-term slope displacement prediction in the Universal Landslide Monitoring Program,an unprecedented disaster mitigation program in China,where lots of newly established monitoring slopes lack sufficient historical deformation data,making it difficult to extract deformation patterns and provide effective predictions which plays a crucial role in the early warning and forecasting of landslide hazards.A slope displacement prediction method based on transfer learning is therefore proposed.Initially,the method transfers the deformation patterns learned from slopes with relatively rich deformation data by a pre-trained model based on a multi-slope integrated dataset to newly established monitoring slopes with limited or even no useful data,thus enabling rapid and efficient predictions for these slopes.Subsequently,as time goes on and monitoring data accumulates,fine-tuning of the pre-trained model for individual slopes can further improve prediction accuracy,enabling continuous optimization of prediction results.A case study indicates that,after being trained on a multi-slope integrated dataset,the TCN-Transformer model can efficiently serve as a pretrained model for displacement prediction at newly established monitoring slopes.The three-day average RMSE is significantly reduced by 34.6%compared to models trained only on individual slope data,and it also successfully predicts the majority of deformation peaks.The fine-tuned model based on accumulated data on the target newly established monitoring slope further reduced the three-day RMSE by 37.2%,demonstrating a considerable predictive accuracy.In conclusion,taking advantage of transfer learning,the proposed slope displacement prediction method effectively utilizes the available data,which enables the rapid deployment and continual refinement of displacement predictions on newly established monitoring slopes. 展开更多
关键词 LANDSLIDE Slope displacement prediction Transfer learning Integrated dataset Transformer Pre-trained model Universal Landslide Monitoring Program(ULMP) Geological hazards survey engineering
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Ecological Environment Monitoring Station of Yanshan Branch,Wenshan Prefecture Ecological Environment Bureau,Yunnan Province,Yanshan 663100,China
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作者 Sumei LI Guofang ZENG +1 位作者 Lei YIN Zhangyue WANG 《Meteorological and Environmental Research》 2024年第5期14-16,20,共4页
How ecological environmental monitoring provides scientific and technological strength for ecological environmental management was studied.In recent years,the Ecological Environment Monitoring Station of Yanshan Branc... How ecological environmental monitoring provides scientific and technological strength for ecological environmental management was studied.In recent years,the Ecological Environment Monitoring Station of Yanshan Branch,Wenshan Prefecture Ecological Environment Bureau,Yunnan Province has developed into a provincial environmental education base,a provincial science education base,and a national environmental protection facility open to the public by relying on monitoring equipment and facilities,personnel training,monitoring and law enforcement interaction,analysis of abnormal data,and countermeasures and suggestions were put forward for the problems in the development. 展开更多
关键词 Ecological environment monitoring Ecological environment management Scientific and technological strength
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Automatic Monitoring System for 3-D Deformation of Crustal Fault Based on Laser and Machine Vision
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作者 Qingshan Wang Guoying Su +3 位作者 Qingzun Ma Haiquan Yin Zhihang Liu Chuanzhen Lv 《Instrumentation》 2024年第2期44-52,共9页
An automatic monitoring method of the 3-D deformation is presented for crustal fault based on laser and machine vision. The laser source and screen are independently set up in the headwall and footwall, the collimated... An automatic monitoring method of the 3-D deformation is presented for crustal fault based on laser and machine vision. The laser source and screen are independently set up in the headwall and footwall, the collimated laser beam creates a circular spot on the screen, meanwhile, the industrial camera captures the tiny deformation of the crustal fault by monitoring the change of the spot position. This method significantly reduces the cost of equipment and labor, provides daily sampling to ensure high continuity of data. A prototype of the automatic monitoring system is developed, and a repeatability test indicates that the error of spot jitter can be minimized by consecutive samples. Meanwhile, the environmental correction model is determined to ensure that environmental changes do not disturb the system. Furthermore, the automatic monitoring system has been applied at the deformation monitoring station(KJX02) of China Beishan underground research laboratory, where continuous deformation monitoring is underway. 展开更多
关键词 deformation measurement crustal fault automatic monitoring laser spot machine vision
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Protocol for detection of pathogenic enteric RNA viruses by regular monitoring of environmental samples from wastewater treatment plants using droplet digital PCR 被引量:1
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作者 Ram Kumar Nema Surya Singh +5 位作者 Ashutosh Kumar Singh Devojit Kumar Sarma Vishal Diwan Rajnarayan R.Tiwari Rajesh Kumar Mondal Pradyumna Kumar Mishra 《Science in One Health》 2024年第1期207-214,共8页
Background:The present comprehensive protocol is focused on the detection of pathogenic enteric RNA viruses,explicitly focusing on norovirus genogroup II(GII),astrovirus,rotavirus,Aichi virus,sapovirus,hepatitis A and... Background:The present comprehensive protocol is focused on the detection of pathogenic enteric RNA viruses,explicitly focusing on norovirus genogroup II(GII),astrovirus,rotavirus,Aichi virus,sapovirus,hepatitis A and E viruses in wastewater treatment plants through droplet digital PCR(ddPCR).Enteric viruses are of significant public health concern,as they are the leading cause of diseases like gastroenteritis.Regular monitoring of environmental samples,particularly from wastewater treatment plants,is crucial for early detection and control of these viruses.This research aims to improve the understanding of the prevalence and dynamics of enteric viruses in urban India and will serve as a model for similar studies in other regions.Our protocol's objective is to establish a novel ddPCRbased methodology for the detection and molecular characterization of enteric viruses present in wastewater samples sourced from Bhopal,India.Our assay is capable of accurately quantifying virus concentrations without standard curves,minimizing extensive optimization,and enhancing sensitivity and precision,especially for low-abundance targets.Methods:The study involves fortnightly collecting and analyzing samples from nine wastewater treatment plants over two years,ensuring comprehensive coverage and consistent data.Our study innovatively applies ddPCR to simultaneously detect and quantify enteric viruses in wastewater,a more advanced technique.Additionally,we will employ next-generation sequencing for detailed viral genome identification in samples tested positive for pathogenic viruses.Conclusion:This study will aid in understanding these viruses’genetic diversity and mutation rates,which is crucial for developing tailored intervention strategies.The findings will be instrumental in shaping public health responses and improving epidemiological surveillance,especially in localities heaving sewage networks. 展开更多
关键词 Enteric RNA viruses Norovirus GII Wastewater treatment plants Droplet digital PCR Environmental surveillance Public health
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Method of Improving the Bacteriological Monitoring Quality in Water
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作者 Zhang Honglian Jiang Peiyu 《Meteorological and Environmental Research》 CAS 2015年第5期38-39,44,共3页
Due to lack of quantitative standard reference material, bacteriological monitoring has the characteristics of strong professionality and heavy workload. It is necessary to conduct quality control in sampling preparat... Due to lack of quantitative standard reference material, bacteriological monitoring has the characteristics of strong professionality and heavy workload. It is necessary to conduct quality control in sampling preparation, sample collection technology, sample preservation and transportation, laboratory equipment, supply quality and monitoring personnel requirements in order to improve the quality of monitoring data and ensure the representativeness, accuracy, precision, comparability and integrity of the monitoring results. 展开更多
关键词 MICROORGANISM Bacteriological monitoring Indicator bacteria Monitoring quality China
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On-line Automatic Monitoring and Control Management of Environmental Pollution Sources
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作者 YOU Chenting 《外文科技期刊数据库(文摘版)自然科学》 2021年第4期038-041,共6页
In modern society, the level of science and technology changes with the changes of the times. Science and technology are widely used in various industries and also play a very important role. The online automatic dete... In modern society, the level of science and technology changes with the changes of the times. Science and technology are widely used in various industries and also play a very important role. The online automatic detection and monitoring system for environmental pollution sources is an embodiment of adopting advanced environmental protection technology. In practice, the system is mainly based on complex technologies such as computer technology and sensors to detect the source of pollutants. With the application of advanced technology for many times, the practical application of this system becomes more and more common. Based on this, this paper discusses the relevant contents of the online automatic monitoring and control management system for environmental pollution sources. 展开更多
关键词 environmental pollution source online automatic monitoring data transmission monitoring measures
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Discussion on the Role of Environmental Monitoring in Environmental Protection Acceptance Monitoring
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作者 YAN Huijun 《外文科技期刊数据库(文摘版)自然科学》 2020年第2期001-006,共6页
Since entering the 21st century, China's environmental protection work is facing new pressure, which makes environmental monitoring and environmental impact assessment become the key work. In the process of enviro... Since entering the 21st century, China's environmental protection work is facing new pressure, which makes environmental monitoring and environmental impact assessment become the key work. In the process of environmental protection acceptance monitoring, relevant management personnel should comply with relevant standards and regulations, enrich the acceptance items and specific contents and establish a more perfect environmental protection acceptance basis, so as to ensure the development of environmental protection acceptance monitoring smoothly. 展开更多
关键词 environmental monitoring environmental protection acceptance MONITORING ROLE
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Monitoring mine collapse by D-InSAR 被引量:22
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作者 YANG Chengsheng ZHANG Qin +2 位作者 ZHAO Chaoying JI Lingyun ZHU Wu 《Mining Science and Technology》 EI CAS 2010年第5期696-700,共5页
For harmful ground collapse and its special deformation characteristics,which causes SAR images to lose coherence,InSAR technology cannot be applied in monitoring surface collapse in mining areas.We took the Shenmu mi... For harmful ground collapse and its special deformation characteristics,which causes SAR images to lose coherence,InSAR technology cannot be applied in monitoring surface collapse in mining areas.We took the Shenmu mining area in northern Shaanxi province as an example to study subsidence in mining areas and proposed an interpolated multi-view processing method.The results show that this method can improve the detectable deformation gradient to a certain extent and can become a good reference value for monitoring large scale gradient deformation.We also analyzed the rules for temporal decorrelation in mining. 展开更多
关键词 D-INSAR coal mine subsidence monitoring COLLAPSE temporal decorrelation interpolated multi-view
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Development and prospect of mobile gravity monitoring and earthquake forecasting in recent ten years in China 被引量:3
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作者 Yiqing Zhu Fang Liu +1 位作者 Guoqing Zhang Yunma Xu 《Geodesy and Geodynamics》 2019年第6期485-491,共7页
After the Wenchuan earthquake in 2008,China Earthquake Administration has strengthened the monitoring of mobile gravity and earthquake forecasting.This paper mainly analyzes the development of mobile gravity monitorin... After the Wenchuan earthquake in 2008,China Earthquake Administration has strengthened the monitoring of mobile gravity and earthquake forecasting.This paper mainly analyzes the development of mobile gravity monitoring network of China in 2008,the role of time-varying gravity field in the determination of strong earthquake risk and the technical problems that gravity monitoring still needs to be solved.By analysing the mobile gravity monitoring and earthquake prediction in China,the characteristics of gravity anomaly and three elements of earthquake prediction are discussed.The mobile gravity observation data can better reflect the gravity anomalies before the earthquake,especially the strong earthquakes greater than Ms6.0.Finally,we put forward the reconsideration of the development strategy of mobile gravity monitoring and earthquake forecasting in China. 展开更多
关键词 MOBILE GRAVITY MONITORING WENCHUAN EARTHQUAKE Lushan EARTHQUAKE EARTHQUAKE prediction
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A framework for investigating the air quality variation characteristics based on the monitoring data: Case study for Beijing during 2013–2016 被引量:2
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作者 Jixian Cui Jianlei Lang +4 位作者 Tian Chen Shushuai Mao Shuiyuan Cheng Zhanshan Wang Nianliang Cheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第7期225-237,共13页
In this study, an analysis framework based on the regular monitoring data was proposed for investigating the annual/inter-annual air quality variation and the contributions from different factors(i.e., seasons, pollut... In this study, an analysis framework based on the regular monitoring data was proposed for investigating the annual/inter-annual air quality variation and the contributions from different factors(i.e., seasons, pollution periods and airflow directions), through a case study in Beijing from 2013 to 2016. The results showed that the annual mean concentrations(MC) of PM_(2.5), SO_2, NO_2 and CO had decreased with annual mean ratios of 7.5%, 28.6%, 4.6%and 15.5% from 2013 to 2016, respectively. Among seasons, the MC in winter contributed the largest fractions(25.8%~46.4%) to the annual MC, and the change of MC in summer contributed most to the inter-annual MC variation(IMCV) of PM_(2.5) and NO2. For different pollution periods, gradually increase of frequency of S-1(PM_(2.5), 0~ 75 μg/m^3) made S-1 become the largest contributor(28.8%) to the MC of PM_(2.5) in 2016, it had a negative contribution(-13.1%) to the IMCV of PM_(2.5); obvious decreases of frequencies of heavily polluted and severely polluted dominated(44.7% and 39.5%) the IMCV of PM_(2.5). For different airflow directions, the MC of pollutants under the south airflow had the most significant decrease(22.5%~62.5%), and those decrease contributed most to the IMCV of PM_(2.5)(143.3%),SO2(72.0%), NO_2(55.5%) and CO(190.3%); the west airflow had negative influences to the IMCV of PM_(2.5), NO_2 and CO. The framework is helpful for further analysis and utilization of the large amounts of monitoring data; and the analysis results can provide scientific supports for the formulation or adjustment of further air pollution mitigation policy. 展开更多
关键词 Monitoring data analysis Air quality variations AIRFLOW DIRECTIONS Pollution PERIODS BEIJING
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Fiber optic displacement sensor used in railway turnout contact monitoring system 被引量:4
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作者 XU Hong-bin LI Feng +3 位作者 ZHAO Wei-gang TIAN Xiu-shu DU Yan-liang GAO Yang 《Optoelectronics Letters》 EI 2019年第3期165-169,共5页
Railway turnout contact monitoring is very important in high-speed rail operation systems. In order to measure the distance between the sharp rail and the basic rail in a switch system, a wide-range, high-precision fi... Railway turnout contact monitoring is very important in high-speed rail operation systems. In order to measure the distance between the sharp rail and the basic rail in a switch system, a wide-range, high-precision fiber Bragg grating(FBG) displacement sensor was designed. Because the distance between the sharp and basic rails is always greater than 14 cm, the measurement range width and accuracy of the proposed sensor system are ensured through the use of a long spring and a beam of constant strength. A differential compensation method is used to eliminate temperature effects. Test results show that the resolution of the proposed sensor is 0.040 mm and the measuring range is 0—170 mm. A field test was also carried out to evaluate the performance of the sensors. 展开更多
关键词 FBG Fiber OPTIC displacement sensor USED in RAILWAY TURNOUT contact monitoring system
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Monitoring and Assessment of Water Quality of Centralized Drinking Water Sources in Kaixian County during the " Twelfth Five-year Plan " Period 被引量:3
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作者 Li Zhang'an 《Meteorological and Environmental Research》 CAS 2015年第10期23-25,29,共4页
Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns (townships or streets) of Kaixian County in the first and second half of each year during the "Twelfth Fi... Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns (townships or streets) of Kaixian County in the first and second half of each year during the "Twelfth Five-year Plan" period, the changing rules of the water quality were studied to provide scientific references for the improvement of drinking water safety of urban and rural residents and drinking water quality. The re- sults show that the water quality of centralized drinking water sources in Kaixian County improved year by year during the "Twelfth Five-year Plan" period, and most monitoring sites with water quality exceeding the standard are distributed in reservoirs. Total phosphorus, total nitrogen, chemical oxygen demand, and permanganate index exceeded the standard obviously. Main pollution sources are domestic pollution and non-point source pol- lution caused by excessive discharge of nitrogen, phosphorus and organic pollutants. To improve drinking water quality, it is suggested that some towns can get drinking water from other reservoirs, surface water or underground water with better quality instead of previous reservoirs with water quality exceeding the standard, and the control of non-point source pollution should be enhanced. 展开更多
关键词 "Twelfth Five-year Plan" period Centralized drinking water Water quality~ Monitoring Assessment Kaixian County
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Upgrading a regional groundwater level monitoring network for Beijing Plain,China 被引量:9
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作者 Yangxiao Zhou Dianwei Dong +1 位作者 Jiurong Liu Wenpeng Li 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第1期127-138,共12页
Monitoring of regional groundwater levels provides important information for quantifying groundwater depletion and assessing impacts on the environment. Historically, groundwater level monitoring wells in Beijing Plai... Monitoring of regional groundwater levels provides important information for quantifying groundwater depletion and assessing impacts on the environment. Historically, groundwater level monitoring wells in Beijing Plain, China, were installed for assessing groundwater resources and for monitoring the cone of depression. Monitoring wells are clustered around well fields and urban areas. There is urgent need to upgrade the existing monitoring wells to a regional groundwater level monitoring network to acquire information for integrated water resources management. A new method was proposed for designing a regional groundwater level monitoring network. The method is based on groundwater regime zone mapping. Groundwater regime zone map delineates distinct areas of possible different groundwater level variations and is useful for locating groundwater monitoring wells. This method was applied to Beijing Plain to upgrade a regional groundwater level monitoring network. 展开更多
关键词 Groundwater monitoring Groundwater regime zone Monitoring network Beijing Plain China
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Current situation and trend of marine data buoy and monitoring network technology of China 被引量:14
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作者 WANG Juncheng WANG Zhongqiu +2 位作者 WANG Yiming LIU Shixuan LI Yunzhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期1-10,共10页
Marine data buoy can provide a long-term, continuous, real-time, reliable data of ocean observation in a variety of complex marine environment. It is one of the most reliable, most effective and important means of oce... Marine data buoy can provide a long-term, continuous, real-time, reliable data of ocean observation in a variety of complex marine environment. It is one of the most reliable, most effective and important means of ocean monitoring technology. In this paper, the classification, main theory and technology system of marine data buoy are summarized. The typical technological breakthrough of the development of marine data buoy in recent years is summarized. The composition and application of marine monitoring network in China was introduced, and the gap between the technology of China's marine data buoy and the international advanced countries is compared.Combined on the situation and demand of China's current situation and needs, the development trend of marine data buoy and buoy monitoring network are expected. 展开更多
关键词 marine monitoring buoy marine observation monitoring network current situation and trend
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Stability evaluation for steep bank slope with microseismic monitoring in Three Gorges Reservoir area 被引量:3
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作者 XIE Qing-ming LONG Kui +7 位作者 LI Zi-mu CHEN Li-chuan LIU Hong XU Hong HE Fei LIANG Dan XIANG Xue-kun MA Qiang 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1588-1601,共14页
Rock slide is one of the common geohazard in the Three Gorges Reservoir area, and it affects the shipping of the Yangtze River and the safety of people living on the banks. In order to investigate the internal fractur... Rock slide is one of the common geohazard in the Three Gorges Reservoir area, and it affects the shipping of the Yangtze River and the safety of people living on the banks. In order to investigate the internal fracturing mechanism of rock mass, distributed microseismic monitoring network was arranged with 15 three component geophones(3C geophones), deployed at borehole and out of the sliding mass in the unstable Dulong slope. Stein Unbiased Risk Estimation(SURE) method was used to noise suppression for the microseismic record, and decomposition parameters of the Continuous Wavelet Transform(CWT) were determined with maximum energy of correlation coefficient(MECC) method. The signal-to-noise ratio was tripled after the process, and source parameters are obtained with full waveform inversion. The rupture volume model was counted by the irregular grid statistics with the events’ density. It shows that the rock slide is of a small scale and composed of a single block. Moreover, the relationship among microseismicity, displacement and rainfall were discussed in the paper. The deformation rate was dramatically changed in the period of intensive events. There is a good consistency especially in the rainfall period. Although there is a time delay, continuous rainfall is more likely to cause the increase of microseismic events. The results show that the Dulong slope is a shallow rock slide in the state of creep deformation, and the rupture mechanism of the rock mass is left-lateral normal fault with shear failure. The research provides more key information for the early warning and prevention of rock slides and helps to reduce the risk of geohazards. 展开更多
关键词 Stability evaluation Microseismic monitoring Rock slide RAINFALL DISPLACEMENT
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