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Long-term monitoring of active large-scale landslides for non-structural risk mitigation-integrated sensors and web-based platform
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作者 CATELAN Filippo Tommaso BOSSI Giulia +8 位作者 SCHENATO Luca TONDO Melissa CRITELLI Vincenzo MULAS Marco CICCARESE Giuseppe CORSINI Alessandro TONIDANDEL David MAIR Volkmar MARCATO Gianluca 《Journal of Mountain Science》 2025年第1期1-15,共15页
Large-scale deep-seated landslides pose a significant threat to human life and infrastructure.Therefore,closely monitoring these landslides is crucial for assessing and mitigating their associated risks.In this paper,... Large-scale deep-seated landslides pose a significant threat to human life and infrastructure.Therefore,closely monitoring these landslides is crucial for assessing and mitigating their associated risks.In this paper,the authors introduce the So Lo Mon framework,a comprehensive monitoring system developed for three large-scale landslides in the Autonomous Province of Bolzano,Italy.A web-based platform integrates various monitoring data(GNSS,topographic data,in-place inclinometer),providing a user-friendly interface for visualizing and analyzing the collected data.This facilitates the identification of trends and patterns in landslide behaviour,enabling the triggering of warnings and the implementation of appropriate mitigation measures.The So Lo Mon platform has proven to be an invaluable tool for managing the risks associated with large-scale landslides through non-structural measures and driving countermeasure works design.It serves as a centralized data repository,offering visualization and analysis tools.This information empowers decisionmakers to make informed choices regarding risk mitigation,ultimately ensuring the safety of communities and infrastructures. 展开更多
关键词 Web-based platform South Tyrol landslides Long term monitoring Risk mitigation
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Long-term monitoring and source apportionment of PM_(2.5)/PM_(10) in Beijing,China 被引量:67
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作者 WANG Hailin ZHUANG Yahui +4 位作者 WANG Ying SUN Yele YUAN Hui ZHUANG Guoshun HAO Zhengping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第11期1323-1327,共5页
During 2001-2006,PM2.5 (particle matter with aerodynamic diameter less than 2.5 microns) and PM10 (particle matter with aerodynamic diameter less than 10 microns) were collected at the Beijng Normal University (BNU) s... During 2001-2006,PM2.5 (particle matter with aerodynamic diameter less than 2.5 microns) and PM10 (particle matter with aerodynamic diameter less than 10 microns) were collected at the Beijng Normal University (BNU) site,China,and in 2006,at a background site in Duolun (DL).The long-term monitoring data of elements,ions,and black carbon showed that the major constituents of PM2.5 were black carbon (BC) crustal elements,nitrates,ammonium salts,and sulfates.These five major components accounted for 20%-80% of... 展开更多
关键词 PM2.5 PM10 monitorING source apportionment
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Structural condition assessment of long-span suspension bridges using long-term monitoring data 被引量:14
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作者 Deng Yang~+,Ding Youliang~(++) and Li Aiqun~§Key Laboratory of Concrete & Prestressed Concrete Structures of Ministry of Education,Southeast University,Nanjing 210096,China PhD Student ++ Assistant Professor ~§Professor 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第1期123-131,共9页
This paper focuses on developing an online structural condition assessment technique using long-term monitoring data measured by a structural health monitoring system. The seasonal correlations of frequency-temperatur... This paper focuses on developing an online structural condition assessment technique using long-term monitoring data measured by a structural health monitoring system. The seasonal correlations of frequency-temperature and beam-end displacement-temperature for the Runyang Suspension Bridge are performed, first. Then, a statistical modeling technique using a six-order polynomial is further applied to formulate the correlations of frequency-temperature and displacement-temperature, from which abnormal changes of measured frequencies and displacements are detected using the mean value control chart. Analysis results show that modal frequencies of higher vibration modes and displacements have remarkable seasonal correlations with the environmental temperature and the proposed method exhibits a good capability for detecting the micro damage-induced changes of modal frequencies and displacements. The results demonstrate that the proposed method can effectively eliminate temperature complications from frequency and displacement time series and is well suited for online condition monitoring of long-span suspension bridges. 展开更多
关键词 structural health monitoring modal frequency beam-end displacement TEMPERATURE seasonal correlation suspension bridge
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ADCP application for long-term monitoring of coastal water 被引量:4
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作者 YOSHIOKA Hiroshi TAKAYAMA Tomotsuka SERIZAWA Shigeatsu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第1期95-100,共6页
Three kind of application of ADCP is reported for long-term monitoring in coastal sea.(1)The routine monitoring of water qualities. The water quality and ADCP echo data (600 kHz) observed in the long-term are analgzed... Three kind of application of ADCP is reported for long-term monitoring in coastal sea.(1)The routine monitoring of water qualities. The water quality and ADCP echo data (600 kHz) observed in the long-term are analgzed at MT (Marine Tower) Station of Kansai International Airport in the Osaka Bay, Japan. The correlation between the turbidity and echo intensity in the surface layer is not good because air bubbles generated by breaking wave are not detected by the turbidity meter, but detected well by ADCP. When estimating the turbidity consists of plankton population from echo intensity, the effect of bubbles have to be eliminated. (2) Monitoring stirring up of bottom sediment. The special observation was carried out by using following two ADCP in the Osaka Bay, One ADCP was installed upward on the sea. The other ADCP was hanged downward at the gate type stand about 3 m above from the bottom. At the spring tide, high echo intensities indicating the stirring up of bottom sediment were observed. (3) The monitoring for the boundary condition of water mixing at an estuary. In summer season, the ADCP was set at the mouth of Tanabe Bay in Wakayama Prefecture, Japan. During the observation, water temperature near the bottom showed remarkable falls with interval of about 5-7 d. When the bottom temperature fell, the inflow current with low echo intensity water appears at the bottom layer in the ADCP record. It is concluded that when occasional weak northeast wind makes weak coastal upwelling at the mouth of the bay, the combination of upwelling with internal tidal flow causes remarkable water exchange and dispels the red tide. 展开更多
关键词 ADCP echo intensity monitoring coastal water red tide stirring up
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Long-Term Monitoring of Environmental Change in German Towns through the Use of Lichens as Biological Indicators: Comparison between the Surveys of 1970, 1980, 1985, 1995, 2005 and 2010 in Wetzlar and Giessen
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作者 Ulrich KIRSCHBAUM Rainer CEZANNE: +2 位作者 Marion EICHLER Klaus HANEWALD Ute WINDISCH 《重庆师范大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第1期41-41,共1页
关键词 英文摘要 编辑工作 学术论文 期刊
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New method for long-term monitoring of intragastric pH
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作者 Shouko Ono Mototsugu Kato +1 位作者 Yuji Ono Masahiro Asaka 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第47期6410-6413,共4页
AIM: Consecutive monitoring of intragastric pH using the Bravo? capsule. METHODS: We put threads through a Bravo? capsule and then affixed it to the gastric wall by endoscopic hemoclipping in seven subjects. Study dat... AIM: Consecutive monitoring of intragastric pH using the Bravo? capsule. METHODS: We put threads through a Bravo? capsule and then affixed it to the gastric wall by endoscopic hemoclipping in seven subjects. Study data were uploaded to a computer via Datalink every 48 h. In this way,repeated monitoring of intragastric pH was undertaken. RESULTS: All subjects were able to monitor gastric pH over a 1-wk period,and five for > 2 wk. No complications were encountered during the monitoring. After pH monitoring,we safely retrieved the capsule endoscopically. CONCLUSION: Clipping a Bravo? capsule onto the gastric wall enabled long-term intragastric pH monitoring. This is a methodological report of pH monitoring over a period of > 2 wk. 展开更多
关键词 Gastric pH Ambulatory monitoring Bravo system
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Long-term monitoring of the recruitment and dynamics of large wood in Kamienica Stream, Polish Carpathians
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作者 Pawel MIKUS Bartlomiej WYZGA 《Journal of Mountain Science》 SCIE CSCD 2020年第6期1281-1293,共13页
Studies presenting long-term observations of the recruitment and mobility of large wood in mountain watercourses are scarce,but they can considerably contribute to the knowledge of river/riparian forest interactions a... Studies presenting long-term observations of the recruitment and mobility of large wood in mountain watercourses are scarce,but they can considerably contribute to the knowledge of river/riparian forest interactions and the assessment of flood hazard resulting from wood mobility during floods.Widespread dieback of riparian forest along the headwater course of Kamienica Stream in the Polish Carpathians,caused by bark beetle infestation of spruce trees,has raised concerns about potential increases of large wood recruitment to the stream and of the flood hazard to downstream valley reaches.In October 2009,429 trees growing along three sections of the stream were tagged with numbered metal plates and monitored over 10 years to determine the timing and causes of their delivery to the channel and the lengths of their displacement during individual flood events.Moreover,in 2012 the mode of location of wood deposits and a degree of wood decay were determined in the second-to fourth-order stream reaches.The monitoring of tagged trees indicated that trees were recruited to the channel during highintensity meteorological and hydrological events,mostly as a result of bank erosion during floods or windthrow.With 22%of tagged trees recruited to the channel during 10 years,the rate of turnover of the riparian trees was estimated at 45 years.As the riparian area is overgrown with trees with ages up to^160 years,the rate evidences substantial intensification of large wood recruitment to the channel in the recent period.Results of large wood inventory and the 10-year-long monitoring of tagged trees indicated variable mobility of large wood along the upper course of the stream.Wood mobility was negligible in the second-order stream reach,very small in the third-order reach,and greater,but still limited in the fourth-order reach.Wood is transported longer distances only during major floods.However,the advanced state of decay of most pieces leads to their disintegration during floods,precluding distant transport.Thus,large wood retained in the upper stream course does not constitute an important flood hazard to downstream,inhabited valley reaches. 展开更多
关键词 Large wood Wood dynamics Wood monitoring Wood inventory Wood recruitment Polish Carpathians
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Long-term monitoring and GIS based determination of groundwater drought propagation,the Lower Silesia region,SW Poland
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作者 Jacek Gurwin 《Episodes》 2014年第3期172-181,共10页
Droughts may be caused by both natural and anthropogenic factors and delimitation of them is crucial for identification of exposed areas.This study concentrated on the application of the threshold level method combine... Droughts may be caused by both natural and anthropogenic factors and delimitation of them is crucial for identification of exposed areas.This study concentrated on the application of the threshold level method combined with GIS modelling applied to hydrogeological drought characterization.The first step was to define groundwater drought periods and analysis of drought intensity and duration based on long-term monitoring data from points evenly spaced within the study area.Then the distribution of hydrogeological drought intensity was identified combining a geostatistical kriging method with the type of geographical region.Utilizing GIS modelling with integration of several parameters the final map was created showing vulnerability and exposure of the area to hydrogeological drought.Studies indicate that the area most exposed to drought is located in the north eastern part of Lower Silesia being influenced by water abstraction and mining activity as well as drought. 展开更多
关键词 gis modelling identification exposed areasthis threshold level method analysis drought intensity duration distribution hydrogeologi groundwater drought define groundwater drought periods long term monitoring
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A miniaturized wireless electrical impedance myography platform for the long-term adaptive muscle fatigue monitoring
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作者 Shanshan Yu Yichao Gan +3 位作者 Feifan Song Qiongzhang Wang Hao Tang Zhao Li 《Journal of Semiconductors》 2025年第10期76-87,共12页
Accurate quantification of exercise interventions and changes in muscle function is essential for personalized health management.Electrical impedance myography(EIM)technology offers an innovative,noninvasive,painless,... Accurate quantification of exercise interventions and changes in muscle function is essential for personalized health management.Electrical impedance myography(EIM)technology offers an innovative,noninvasive,painless,and easy-to-perform solution for muscle health monitoring.However,current EIM platforms face a number of limitations,including large device size,wired connections,and instability of the electrode-skin interface,which limit their applicability for monitoring mus-cle movement.In this study,a miniature wireless EIM platform with a user-friendly smartphone app is proposed and devel-oped.The miniature,wireless,multi-frequency(20 kHz-1 MHz)EIM platform is equipped with flexible microneedle array elec-trodes(MAE).The advantages of MAEs over conventional electrodes were demonstrated by physical field modeling simula-tions and skin-electrode contact impedance comparison tests.The smartphone APP was developed to wirelessly operate the EIM platform,and to transmit and process real-time muscle impedance data.To validate its effectiveness,a seven-day adaptive fatigue training study was conducted,which demonstrated that the EIM platform was able to detect muscle adaptations and serve as a reliable indicator of fatigue.This study presents an innovative approach to applying EIM technology to muscle health monitoring and exercise testing,thereby advancing the development of personalized health management and athletic performance assessment. 展开更多
关键词 electrical impedance myography flexible microneedle array electrodes miniaturized wireless platform smartphone APP muscle fatigue monitoring
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Robust and Biodegradable Heterogeneous Electronics with Customizable Cylindrical Architecture for Interference-Free Respiratory Rate Monitoring
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作者 Jing Zhang Wenqi Wang +9 位作者 Sanwei Hao Hongnan Zhu Chao Wang Zhouyang Hu Yaru Yu Fangqing Wang Peng Fu Changyou Shao Jun Yang Hailin Cong 《Nano-Micro Letters》 2026年第1期914-934,共21页
A rapidly growing field is piezoresistive sensor for accurate respiration rate monitoring to suppress the worldwide respiratory illness.However,a large neglected issue is the sensing durability and accuracy without in... A rapidly growing field is piezoresistive sensor for accurate respiration rate monitoring to suppress the worldwide respiratory illness.However,a large neglected issue is the sensing durability and accuracy without interference since the expiratory pressure always coupled with external humidity and temperature variations,as well as mechanical motion artifacts.Herein,a robust and biodegradable piezoresistive sensor is reported that consists of heterogeneous MXene/cellulose-gelation sensing layer and Ag-based interdigital electrode,featuring customizable cylindrical interface arrangement and compact hierarchical laminated architecture for collectively regulating the piezoresistive response and mechanical robustness,thereby realizing the long-term breath-induced pressure detection.Notably,molecular dynamics simulations reveal the frequent angle inversion and reorientation of MXene/cellulose in vacuum filtration,driven by shear forces and interfacial interactions,which facilitate the establishment of hydrogen bonds and optimize the architecture design in sensing layer.The resultant sensor delivers unprecedented collection features of superior stability for off-axis deformation(0-120°,~2.8×10^(-3) A)and sensing accuracy without crosstalk(humidity 50%-100%and temperature 30-80).Besides,the sensor-embedded mask together with machine learning models is achieved to train and classify the respiration status for volunteers with different ages(average prediction accuracy~90%).It is envisioned that the customizable architecture design and sensor paradigm will shed light on the advanced stability of sustainable electronics and pave the way for the commercial application in respiratory monitory. 展开更多
关键词 Wearable electronics Piezoresistive sensor HETEROGENEOUS CELLULOSE Respiratory monitoring
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Intelligent Semantic Segmentation with Vision Transformers for Aerial Vehicle Monitoring
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作者 Moneerah Alotaibi 《Computers, Materials & Continua》 2026年第1期1629-1648,共20页
Advanced traffic monitoring systems encounter substantial challenges in vehicle detection and classification due to the limitations of conventional methods,which often demand extensive computational resources and stru... Advanced traffic monitoring systems encounter substantial challenges in vehicle detection and classification due to the limitations of conventional methods,which often demand extensive computational resources and struggle with diverse data acquisition techniques.This research presents a novel approach for vehicle classification and recognition in aerial image sequences,integrating multiple advanced techniques to enhance detection accuracy.The proposed model begins with preprocessing using Multiscale Retinex(MSR)to enhance image quality,followed by Expectation-Maximization(EM)Segmentation for precise foreground object identification.Vehicle detection is performed using the state-of-the-art YOLOv10 framework,while feature extraction incorporates Maximally Stable Extremal Regions(MSER),Dense Scale-Invariant Feature Transform(Dense SIFT),and Zernike Moments Features to capture distinct object characteristics.Feature optimization is further refined through a Hybrid Swarm-based Optimization algorithm,ensuring optimal feature selection for improved classification performance.The final classification is conducted using a Vision Transformer,leveraging its robust learning capabilities for enhanced accuracy.Experimental evaluations on benchmark datasets,including UAVDT and the Unmanned Aerial Vehicle Intruder Dataset(UAVID),demonstrate the superiority of the proposed approach,achieving an accuracy of 94.40%on UAVDT and 93.57%on UAVID.The results highlight the efficacy of the model in significantly enhancing vehicle detection and classification in aerial imagery,outperforming existing methodologies and offering a statistically validated improvement for intelligent traffic monitoring systems compared to existing approaches. 展开更多
关键词 Machine learning semantic segmentation remote sensors deep learning object monitoring system
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Noninvasive On-Skin Biosensors for Monitoring Diabetes Mellitus
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作者 Ali Sedighi Tianyu Kou +1 位作者 Hui Huang Yi Li 《Nano-Micro Letters》 2026年第1期375-437,共63页
Diabetes mellitus represents a major global health issue,driving the need for noninvasive alternatives to traditional blood glucose monitoring methods.Recent advancements in wearable technology have introduced skin-in... Diabetes mellitus represents a major global health issue,driving the need for noninvasive alternatives to traditional blood glucose monitoring methods.Recent advancements in wearable technology have introduced skin-interfaced biosensors capable of analyzing sweat and skin biomarkers,providing innovative solutions for diabetes diagnosis and monitoring.This review comprehensively discusses the current developments in noninvasive wearable biosensors,emphasizing simultaneous detection of biochemical biomarkers(such as glucose,cortisol,lactate,branched-chain amino acids,and cytokines)and physiological signals(including heart rate,blood pressure,and sweat rate)for accurate,personalized diabetes management.We explore innovations in multimodal sensor design,materials science,biorecognition elements,and integration techniques,highlighting the importance of advanced data analytics,artificial intelligence-driven predictive algorithms,and closed-loop therapeutic systems.Additionally,the review addresses ongoing challenges in biomarker validation,sensor stability,user compliance,data privacy,and regulatory considerations.A holistic,multimodal approach enabled by these next-generation wearable biosensors holds significant potential for improving patient outcomes and facilitating proactive healthcare interventions in diabetes management. 展开更多
关键词 Wearable biosensors Multimodal sensors Diabetes monitoring Sweat biomarkers Glucose biosensors
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Long-term outcomes following lens extraction surgery in acute primary angle closure
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作者 Yi-Ning Guo Jing Ding +3 位作者 Hao-Ran Ai Xin-Zuo Zhou Xue-Min Li Chun Zhang 《International Journal of Ophthalmology(English edition)》 2026年第2期281-290,共10页
AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longit... AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longitudinal observational study,detailed medical histories of APAC patients and comprehensive ophthalmic examinations at final followup were collected.Logistic regression analysis was performed to identify predictors of blindness.Univariate and multivariate linear regression analyses were conducted to determine risk factors associated with visual outcomes.RESULTS:This study included 39 affected eyes of 31 subjects(26 females)with an average age of 74.1±8.0y.At 6.7±4.2y after APAC attack,2(5.7%)eyes had bestcorrected visual acuity(VA)worse than 3/60.Advanced glaucomatous visual field loss was observed in 15(39.5%)affected eyes and 5(25.0%)fellow eyes.Nine affected eyes(23.7%)had GON,and 11(28.9%)were blind.Six(15.4%)affected eyes and 2(9.1%)fellow eyes had suspicious progression.A significantly higher blindness rate in factory workers compared to office workers.Logistic regression identified that worse VA at attack(OR 10.568,95%CI 1.288-86.695;P=0.028)and worse early postoperative VA(OR 13.214,95%CI 1.157-150.881;P=0.038)were risk factors for blindness.Multivariate regression showed that longer duration of elevated intraocular pressure(P=0.004)and worse early postoperative VA(P=0.009)were associated with worse visual outcomes.CONCLUSION:Despite LE surgery,some APAC patients experience continued visual function deterioration.Lifelong monitoring is necessary.Target pressure and progression rates should be re-evaluated during follow-up. 展开更多
关键词 acute primary angle closure lens extraction surgery long-term follow-up visual impairment glaucomatous optic neuropathy
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Skin-Inspired Ultra-Linear Flexible Iontronic Pressure Sensors for Wearable Musculoskeletal Monitoring
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作者 Pei Li Shipan Lang +6 位作者 Lei Xie Yong Zhang Xin Gou Chao Zhang Chenhui Dong Chunbao Li Jun Yang 《Nano-Micro Letters》 2026年第2期454-470,共17页
The growing prevalence of exercise-induced tibial stress fractures demands wearable sensors capable of monitoring dynamic musculoskeletal loads with medical-grade precision.While flexible pressure-sensing insoles show... The growing prevalence of exercise-induced tibial stress fractures demands wearable sensors capable of monitoring dynamic musculoskeletal loads with medical-grade precision.While flexible pressure-sensing insoles show clinical potential,their development has been hindered by the intrinsic trade-off between high sensitivity and full-range linearity(R^(2)>0.99 up to 1 MPa)in conventional designs.Inspired by the tactile sensing mechanism of human skin,where dermal stratification enables wide-range pressure adaptation and ion-channelregulated signaling maintains linear electrical responses,we developed a dual-mechanism flexible iontronic pressure sensor(FIPS).This innovative design synergistically combines two bioinspired components:interdigitated fabric microstructures enabling pressure-proportional contact area expansion(αP1/3)and iontronic film facilitating self-adaptive ion concentration modulation(αP^(2/3)),which together generate a linear capacitance-pressure response(CαP).The FIPS achieves breakthrough performance:242 kPa^(-1)sensitivity with 0.997linearity across 0-1 MPa,yielding a record linear sensing factor(LSF=242,000).The design is validated across various substrates and ionic materials,demonstrating its versatility.Finally,the FIPS-driven design enables a smart insole demonstrating 1.8%error in tibial load assessment during gait analysis,outperforming nonlinear counterparts(6.5%error)in early fracture-risk prediction.The biomimetic design framework establishes a universal approach for developing high-performance linear sensors,establishing generalized principles for medical-grade wearable devices. 展开更多
关键词 Iontronic sensor Skin-inspired design Linear range Linear sensing factor Biomechanical monitoring
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Study on response of AlphaGUARD PQ2000 radon monitor to^(220)Rn and its long‑lived progeny in diffusion mode
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作者 Ke‑Xin Wang Zheng‑Zhong He +6 位作者 Ya‑Song Xiao Jia‑Lu Feng Yan‑Bing Lin Wen‑Jie Xu Li‑Dan Lv Yu‑Qi Xing Hui‑Min Yuan 《Nuclear Science and Techniques》 2026年第1期152-163,共12页
Owing to the inherent limitation of the internal pulse ionization chamber within the AlphaGUARD PQ2000 radon monitor,that is,its inability to discriminate the energy levels of α particles,the ingress of^(220)Rn from ... Owing to the inherent limitation of the internal pulse ionization chamber within the AlphaGUARD PQ2000 radon monitor,that is,its inability to discriminate the energy levels of α particles,the ingress of^(220)Rn from the surrounding environment,along with its decay progeny,poses a substantive challenge in accurately determining the^(222)Rn concentration in the measurement outcomes.Among these,the protracted influence primarily stems from the two enduring decay progenies,namely^(212)Pb with a half-life of 10.64 h and^(212)Bi with a half-life of 60.54 min.This study explored the influence of^(220)Rn progeny on the measurement results of an AlphaGUARD PQ2000 radon monitor by developing a theoretical calculation model.The response coefficient related to the residual^(220)Rn progeny within the AlphaGUARD PQ2000 radon monitor was experimentally validated.In addition,this study investigated the effects of temperature and wind speed on the sensitivity of the instrument to^(220)Rn gas.The research findings revealed commendable agreement between the experimentally measured response coefficients of the residual^(220)Rn progeny and the corresponding values derived from the theoretical model.Notably,both the response coefficients of the AlphaGUARD PQ2000 radon monitor to^(220)Rn gas and its internal residual^(220)Rn progeny increased with elevated temperatures and increased wind speeds,providing a reference for correcting the impact of^(220)Rn and its progeny on the measurement results of^(222)Rn concentration obtained using the AlphaGUARD PQ2000 radon monitor. 展开更多
关键词 ^(220)Rn progeny 222Rn AlphaGUARD PQ2000 long-term decay Response coefficient ^(220)Rn gas Temperature effects Wind speed effects
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Adaptive Change Detection for Long-Term Machinery Monitoring Using Incremental Sliding-Window
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作者 Teng Wang Guo-Liang Lu +1 位作者 Jie Liu Peng Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1338-1346,共9页
Detection of structural changes from an opera- tional process is a major goal in machine condition moni- toring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detec... Detection of structural changes from an opera- tional process is a major goal in machine condition moni- toring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detection delay that limits their usages in real applications. This paper presents a new adaptive real-time change detection algorithm, an extension of the recent research by combin- ing with an incremental sliding-window strategy, to handle the multi-change detection in long-term monitoring of machine operations. In particular, in the framework, Hil- bert space embedding of distribution is used to map the original data into the Re-producing Kernel Hilbert Space (RK_HS) for change detection; then, a new adaptive threshold strategy can be developed when making change decision, in which a global factor (used to control the coarse-to-fine level of detection) is introduced to replace the fixed value of threshold. Through experiments on a range of real testing data which was collected from an experimental rotating machinery system, the excellent detection performances of the algorithm for engineering applications were demonstrated. Compared with state-of- the-art methods, the proposed algorithm can be more suitable for long-term machinery condition monitoring without any manual re-calibration, thus is promising in modern industries. 展开更多
关键词 Machine monitoring Change detection long-term monitoring Adaptive threshold
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Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program
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作者 Mariana A.JUÁRES AnahíM.SILVESTRO +1 位作者 Brenda C.ALFONSO M.Mercedes SANTOS 《Advances in Polar Science》 CSCD 2024年第1期132-140,共9页
In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin... In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point. 展开更多
关键词 long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends
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Investigation on long-term progressive deformation of engineering slope based on comprehensive monitoring 被引量:4
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作者 ZHANG Shi-shu GUO Song-feng +9 位作者 QI Sheng-wen TANG Feng-jiao HU Jin-shan ZHAO Xiao-ping RAN Cong-yan WANG Xin ZOU Yu HUANG Xiao-lin ZHENG Bo-wen LIANG Ning 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1576-1587,共12页
A landslide always results from a progressive process of slope deformation. In recent years, an increasing number of slope instabilities have occurred with regard to human engineering activities such as hydropower or ... A landslide always results from a progressive process of slope deformation. In recent years, an increasing number of slope instabilities have occurred with regard to human engineering activities such as hydropower or traffic construction in mountainous area, which cause even greater casualties and economic loss compared with the natural hazards. The development of such earth surface process may hold long period with mechanisms still not fully understood. Using monitoring technology is an effective and intuitive approach to assist analyzing the slope deformation process and their driving factors. This study presents an engineering slope excavated during the construction of Changheba Hydropower Station, which is located in the upper reaches of Dadu River, Sichuan Province, southwest China. The engineering slope experienced and featured a five-year continuous deformation which caused continuous high risks to the engineering activities. We conducted in-depth analysis for such a long-term deformation process based on ground and subsurface monitoring data, collected successive data with a series of monitoring equipment such as automated total station, borehole inclinometers and other auxiliary apparatus, and identified the deformation process based on the comprehensive analysis of monitoring data as well as field investigation. After analyzing the effects of engineering activities and natural factors on the continuous deformation, we found that the overburden strata provided deformable mass while the excavation-produced steep terrain initiated the slope deformation in limit equilibrium state over a long period of time;afterwards, the intense rainwater accelerated slope deformation in the rainy season. 展开更多
关键词 Engineering slope Mountainous area long-term deformation LANDSLIDES monitorING STABILITY
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Features of long-term health monitored strains of a bridge with wavelet analysis 被引量:5
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作者 Zejia Liu,Bin Jiang,Liqun Tang,Yiping Liu,Chunyu Zhang,and Yinghua Li School of Civil Engineering and Transportation,State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510640,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第5期27-30,共4页
This paper analyses the five years’ monitored strains collected from a long-term health monitoring system installed on a bridge with wavelet transform.In the analysis,the monitored strains are pre-processed,features ... This paper analyses the five years’ monitored strains collected from a long-term health monitoring system installed on a bridge with wavelet transform.In the analysis,the monitored strains are pre-processed,features of the monitored data are summarized briefly.The influences of the base functions on the results of wavelet analysis are studied simultaneously.The results show that the db wavelet is a good mother wavelet function in the analysis,and the order N should be larger than 20,but less than 46 in decomposing the monitored strains of the bridge.According to the strain variation features of concrete bridge,the proper decomposition level is 4 in the wavelet multi-resolution analysis.With the present method,the strains caused by random loads and daily sunlight can be accurately extracted from the monitored strains.The decomposed components of the monitored strains show that the amplitudes of the strains caused by random loads,daily sunlight,and annual temperature effect,are about 5 με,25 με,and 50 με respectively.The structural response under random load is smaller than the other parts. 展开更多
关键词 health monitoring systems wavelet analysis signal processing BRIDGE
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Long-term Field Corrosion Monitoring in Supporting Structures of China Xiamen Xiangan Subsea Tunnel 被引量:1
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作者 Chao-Yang Gong Xiao-Yong He +8 位作者 Yong-Wei Li Si-Zhe He Xuan Cheng Liu-Ying Huang Ying Zhang Jiu-Bin Chen Shao-Hui Xu Jian-Bin Zhang Chao Zeng 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2017年第4期399-408,共10页
Xiamen Xiangan Subsea Tunnel is the first undersea tunnel constructed in China. It has become the major undersea pathway connecting Xiamen Island and Xiangan District since its operation in 2010. The total length is 6... Xiamen Xiangan Subsea Tunnel is the first undersea tunnel constructed in China. It has become the major undersea pathway connecting Xiamen Island and Xiangan District since its operation in 2010. The total length is 6.05 km with the undersea length of 4.2 km. In an effort to onsite-monitor reinforcement corrosion in concrete structures, the commercially available CorroWatch multiprobe sensors and ERE-20 reference electrodes were pre-embedded in the selected locations and positions of supporting structures during the tunnel constructions. The real-time data have been collected annually by onsite measurements for 6 years. In this paper, the feasibility of the onsite corrosion monitoring system and suitability of the measured parameters including corrosion current, potential and temperature are discussed based on the preliminary results. The measured typical cyclic-type variations in corrosion current and temperature with monitoring time might be related to the seasonal changes during the annual routine measurements. The widely scattered corrosion potentials that are fluctuated complicatedly reflected localized differences in the vicinity of rebar and concrete. These findings, along with the progressively ongoing research, will provide valuable information in structural durability for service life prediction of reinforced concrete structures exposed to marine environments. 展开更多
关键词 Corrosion monitor Corrosion current Corrosion behavior SENSORS
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