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Laboratory evaluation of a low-cost micro electro-mechanical systems sensor for inclination and acceleration monitoring
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作者 Antonis Paganis Vassiliki NGeorgiannou +1 位作者 Xenofon Lignos Reina El Dahr 《Deep Underground Science and Engineering》 2025年第1期46-54,共9页
In this study,the design and development of a sensor made of low-cost parts to monitor inclination and acceleration are presented.Αmicro electro-mechanical systems,micro electro mechanical systems,sensor was housed i... In this study,the design and development of a sensor made of low-cost parts to monitor inclination and acceleration are presented.Αmicro electro-mechanical systems,micro electro mechanical systems,sensor was housed in a robust enclosure and interfaced with a Raspberry Pi microcomputer with Internet connectivity into a proposed tilt and acceleration monitoring node.Online capabilities accessible by mobile phone such as real-time graph,early warning notification,and database logging were implemented using Python programming.The sensor response was calibrated for inherent bias and errors,and then tested thoroughly in the laboratory under static and dynamic loading conditions beside high-quality transducers.Satisfactory accuracy was achieved in real time using the Complementary Filter method,and it was further improved in LabVIEW using Kalman Filters with parameter tuning.A sensor interface with LabVIEW and a 600 MHz CPU microcontroller allowed real-time implementation of highspeed embedded filters,further optimizing sensor results.Kalman and embedded filtering results show agreement for the sensor,followed closely by the lowcomplexity complementary filter applied in real time.The sensor's dynamic response was also verified by shaking table tests,simulating past recorded seismic excitations or artificial vibrations,indicating negligible effect of external acceleration on measured tilt;sensor measurements were benchmarked using highquality tilt and acceleration measuring transducers.A preliminary field evaluation shows robustness of the sensor to harsh weather conditions. 展开更多
关键词 field monitoring Kalman filter laboratory evaluation micro electro mechanical systems(MEMS) monitoring node shaking table
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Monitoring,Identification,and Evaluation of Rice Planthoppers Using an Intelligent Small Insect Monitoring and Forecasting System
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作者 Xiudong HUANG Shengwen SHI +1 位作者 Yi LUO Lingli ZHANG 《Plant Diseases and Pests》 2025年第5期7-10,共4页
[Objectives]To assess the effectiveness of the intelligent small insect monitoring and forecasting system developed by Zhejiang Top Cloud-Agri Technology Co.,Ltd.in monitoring,providing early warnings,and identifying ... [Objectives]To assess the effectiveness of the intelligent small insect monitoring and forecasting system developed by Zhejiang Top Cloud-Agri Technology Co.,Ltd.in monitoring,providing early warnings,and identifying rice planthoppers.[Methods]In 2024,an experiment involving the automatic identification and counting of rice planthoppers was conducted using the intelligent small insect monitoring and forecasting system in the rice production demonstration area of Qingxichang Sub-district,Xiushan Autonomous County,Chongqing City.The results obtained were subsequently compared and analyzed against those derived from manual identification.[Results]The intelligent small insect monitoring and forecasting system achieved recognition accuracy rates of 95.14%,94.25%,and 97.78% for Nilaparvata lugens,Sogatella furcifera,and Laodelphax striatellus,respectively,resulting in an average accuracy rate of 95.72%.The outcomes derived from automatic recognition closely corresponded with those obtained through manual identification.[Conclusions]This research provides a reference for the optimization of the intelligent small insect monitoring and forecasting system. 展开更多
关键词 Rice planthopper Intelligent small insect monitoring and forecasting system Recognition accuracy Correlation coefficient Xiushan County
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Evaluation of rock mass quality and its mechanical properties through digital drilling process monitoring
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作者 Xinfang Li Xiaoping Zhang +3 位作者 Quansheng Liu Shaohui Tang Qi Zhang Yongbin Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4490-4511,共22页
The evaluation of rock mass quality and its mechanical properties is crucial for tunnel construction.The basic quality(BQ)method is the national standard for rock mass classification in China,with the BQ value determi... The evaluation of rock mass quality and its mechanical properties is crucial for tunnel construction.The basic quality(BQ)method is the national standard for rock mass classification in China,with the BQ value determined by the uniaxial compressive strength(UCS)and the integrity index(Kv).However,traditional rock mechanics testing methods have inherent limitations,which complicate the rapid evaluation of rock mass quality at tunnel sites.Digital drilling process monitoring(DPM)offers a novel approach for evaluating rock mass quality and its mechanical properties.A hydraulic rotary drilling rig,equipped with the DPM system,was used to conduct digital drilling tests at the tunnel face.The DPM data for the net drilling process and each sub-process were then analyzed.The correlations between DPM parameter indices and rock mechanical parameters were investigated.Finally,the rock mass quality and its mechanical properties along three boreholes were evaluated.The results indicate that drilling speed in the linear zone(V_(DPM))is quantitatively correlated with rock UCS.Higher UCS values of the drilled rocks correspond to lower V_(DPM) values of the drilling rig.The variability in specific energy is associated with structural disturbances within the rock mass.There is an approximately linear relationship between the standard deviation of normalized specific energy and rock mass K_(v) across the three boreholes.The rock mass quality along drilling depth generally ranges from good(Ⅰ-Ⅱ)to poor(Ⅲ-Ⅴ).This digitalization method provides more detailed information for tunnel stability analysis and design optimization than geological survey data. 展开更多
关键词 Basic quality(BQ) Rock mass quality Rock mechanical properties Drilling process monitoring(DPM) Drilling parameters
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Stability monitoring and evaluation of the modeled test square for prehistoric earthen sites during excavation period 被引量:3
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作者 谌文武 戴鹏飞 +3 位作者 张景科 陈鹏飞 郭青林 孙满利 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期464-471,共8页
In order to explore the stability of test square during archaeological excavation for prehistoric earthen sites in Hangzhou, a modeled test square with 2. 3 min depth, inplane dimensions of 5 min width by 5 m in lengt... In order to explore the stability of test square during archaeological excavation for prehistoric earthen sites in Hangzhou, a modeled test square with 2. 3 min depth, inplane dimensions of 5 min width by 5 m in length, and an archaeological column in the middle was excavated by means of a top-down excavation technique. To investigate the stability performance of the modeled test square and the associated effect on the adjacent area, a real-time comprehensive instrumentation program was conducted during the excavation. Field observations included ground settlements, lateral displacement, pore pressure and underground water level. Monitoring data indicates that the ground settlement induced by dewatering and unloading action basically decreases with the increase of the distance away from the pit edge, and the lateral displacements at four sides showa nonlinear variation along the depth. The maximum value is far below the acceptable value regulated by the related standard,which validates the stability of the modeled test square during excavation. Variations of pore pressure and water level suggest that long-term stability should be paid more attention due to the slowconsolidation of soft soil. Meanwhile, it is proved that the step shape of the wall can resist lateral displacement more effectively than the vertical shape of wall. This case study provides insights into the real archaeological excavation in Hangzhou, in particular Liangzhu prehistoric earthen sites. 展开更多
关键词 prehistoric earthen sites archaeological excavation test square stability monitoring
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Evaluation of PS-DInSAR technology for subsidence monitoring caused by repeated mining in mountainous area 被引量:4
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作者 刘振国 卞正富 +2 位作者 雷少刚 刘东烈 Andrew SOWTER 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3309-3315,共7页
The high resolution Terra SAR-X dataset was employed with DIn SAR and persistent scatterer interferometry(PSI) technique for subsidence monitoring in a mountainous area. For DInS AR technique, the generally used SRT... The high resolution Terra SAR-X dataset was employed with DIn SAR and persistent scatterer interferometry(PSI) technique for subsidence monitoring in a mountainous area. For DInS AR technique, the generally used SRTM and relief-DEM, which was derived from aerial topographic map, were used to evaluate the influence of external DEM. The results show that SRTM could not fully compensate the complex topography of the research area. The corner reflectors installed during the acquisition of SAR dataset were used to estimate the accuracy of geocoding. The terrain corrected geocoding results based on relief-DEM were much better than using SRTM, with the root mean square error(RMSE) being 6.35 m in X direction and 11.65 m in Y direction(both in UTM projection), around one pixel of the multilooked intensity image to be geocoded. For PSI technique, the results from time-series analysis of multi-baseline differential interferograms were integrated to restrict only persistent scatterer candidates near the boundary of subsiding area for regression analysis. The results demonstrate that PSI can refine the boundary of subsidence, which could then be used to derive some angular parameters to help people to learn the law of subsidence caused by repeated excavation in this area. 展开更多
关键词 DIn SAR GEOCODING persistent scatterer interferometry(PSI) repeated excavation corner reflector subsidence monitoring
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Annual Monitoring and Evaluation of the Grades of Arable Land Quality——Taking Lingchuan County as an Example 被引量:2
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作者 全坚 谭咪 《Agricultural Science & Technology》 CAS 2017年第6期1112-1119,共8页
With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and developm... With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and development trends of arable land quality. It is also an important measure for protecting the quality of arable land. in the present study, the distribution and changes of arable lands of different gradient types and grades in Lingchuan County, Guangxi Zhuang Autonomous Region in 2015 were monitored and evaluated, to analyze the trends and reasons for the changes in the quality and productivity of arable lands, and to provide references for dynamic monitoring of the quality of arable land. 展开更多
关键词 Arable land grades monitoring evaluation Lingchuan County
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Study on the Evaluation and Monitoring over In-depth Development of Ecotourism
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作者 刘阳炼 《Journal of Landscape Research》 2010年第12期84-88,共5页
Qualitative indexes contained in the product standards of in-depth ecotourism development are summarized as:carrying capacity control,protection of natural environment,participation of community residents,education ab... Qualitative indexes contained in the product standards of in-depth ecotourism development are summarized as:carrying capacity control,protection of natural environment,participation of community residents,education about environment protection,enhancing standard management,clean production,green training,and overall monitoring.Based on the model of grey system theory,the improvement of in-depth ecotourism development was predicted,the construction,evaluation and monitoring model for the in-depth development of ecotourism was established,and finally the index system for the evaluation was set as the General Layer(A),the System Layer(B),the Status Layer(C),and the Variable Layer(D). 展开更多
关键词 ECOTOURISM In-depth DEVELOPMENT evaluation and monitoring Index system
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Application of Participatory Monitoring and Evaluation in Development of Animal Husbandry Technology
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作者 钱敏 宁波 +4 位作者 申时才 陈蕊 李丹桐 彭子芸 吕宏斌 《Agricultural Science & Technology》 CAS 2012年第9期1942-1946,1961,共6页
[Objective] This study aimed to provide references for the application of participatory monitoring and evaluation in the development of animal husbandry tech- nology. [Method] With the livelihood improvement program f... [Objective] This study aimed to provide references for the application of participatory monitoring and evaluation in the development of animal husbandry tech- nology. [Method] With the livelihood improvement program for agricultural and pas- toral area in northern Yunnan as the example, the development process of partici- patory animal husbandry was overviewed. And the monitoring and evaluation pro- cesses of participatory animal husbandry were introduced and analyzed. [Result] The monitoring and evaluation indicator system of participatory animal husbandry technol- ogy included 4 layers, namely technology, institutional system, personnel ability con- struction and effectiveness, and 11 third-level indicators, namely, technical characteristics, superiority-inferiority comparison, community and farmers, technical personnel, project personnel, economic indicators and social indicators. [Conclusion] This study provided the references for the application of participatory monitoring and evaluation in the development of animal husbandry technology. 展开更多
关键词 'Participatory approach Livestock technology development monitoringand evaluation Gongshan County
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Therapeutic effects of low-intensity transcranial focused ultrasound stimulation on ischemic stroke in rats:An in vivo evaluation using electrical impedance tomography
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作者 Jiecheng Guo Sixuan He +4 位作者 Li Yan Lei Wang Xuetao Shi Huijing Hu Le Li 《Neural Regeneration Research》 2026年第3期1183-1190,共8页
Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance to... Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke. 展开更多
关键词 animal model brain stimulation electrical impedance tomography evaluation impedance noninvasive treatment real-time monitoring REHABILITATION STROKE transcranial focused ultrasound stimulation
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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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Construction of a mental health literacy evaluation index system for adolescents with mental disorders
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作者 Ying-Qiong Ge Xiao-Shuang Ouyang +2 位作者 Zheng-Min Zhu Bi-Can Tan Xiao-Jian Jiang 《World Journal of Psychiatry》 2026年第1期299-311,共13页
BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an e... BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an evaluation index system for the mental health literacy of adolescent patients with mental disorders,providing a scientific,comprehensive,and reliable tool for the monitoring and intervention of mental health literacy of such patients.METHODS From December 2022 to June 2023,the evaluation index system for mental health literacy of adolescents with mental disorders was developed through literature reviews,semi-structured interviews,expert letter consultations,and the analytic hierarchy process.Based on this index system,a self-assessment questionnaire was compiled and administered to 305 adolescents with mental disorders to test the reliability and validity of the index system.RESULTS The final evaluation index system for mental health literacy of adolescents with mental disorders included 4 first-level indicators,10 second-level indicators,and 52 third-level indicators.The overall Cronbach’sαcoefficient of the index system was 0.957,with a partial reliability of 0.826 and a content validity index of 0.975.The cumulative variance contribution rate of 10 common factors was 66.491%.The correlation coefficients between each dimension and the total questionnaire ranged from 0.672 to 0.724,while the correlation coefficients in each dimension ranged from 0.389 to 0.705.CONCLUSION The evaluation index system for mental health literacy of adolescents with mental disorders,developed in this study,demonstrated notable reliability and validity,making it a valuable tool for evaluating mental health literacy in this population. 展开更多
关键词 Adolescents Mental disorders Mental health literacy evaluation index system Delphi method
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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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Predictable and Unpredictable Modes of Northern Hemisphere Atmospheric Circulation in CMIP6:Evaluation and Projections
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作者 Kairan YING Dabang JIANG Linhao ZHONG 《Advances in Atmospheric Sciences》 2026年第1期135-156,共22页
Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both g... Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations. 展开更多
关键词 interannual mode of atmospheric circulation CMIP6 predictable unpredictable evaluation PROJECTION
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Stability evaluation for steep bank slope with microseismic monitoring in Three Gorges Reservoir area 被引量:4
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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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Efficient Bayesian networks for slope safety evaluation with large quantity monitoring information 被引量:8
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作者 Xueyou Li Limin Zhang Shuai Zhang 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1679-1687,共9页
New sensing and wireless technologies generate massive data. This paper proposes an efficient Bayesian network to evaluate the slope safety using large-quantity field monitoring information with underlying physical me... New sensing and wireless technologies generate massive data. This paper proposes an efficient Bayesian network to evaluate the slope safety using large-quantity field monitoring information with underlying physical mechanisms. A Bayesian network for a slope involving correlated material properties and dozens of observational points is constructed. 展开更多
关键词 SLOPE reliability monitoring INFORMATION BAYESIAN networks RISK management VALUE of INFORMATION BIG data
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Using Grey Target Theory for Power Quality Evaluation Based on Power Quality Monitoring Data 被引量:4
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作者 Qiang Yu Xiankai Chen +2 位作者 Xiaoyue Li Chaoqun Zhou Zhichao Li 《Energy Engineering》 EI 2022年第1期359-369,共11页
Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is propose... Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is proposed for power quality evaluation.The grey target is composed of power quality evaluation standard and power quality monitoring data to be evaluated.Combining with the characteristics of each power quality evaluation index,the target center of the whole grey target system is found.Then,the power quality monitoring data to be evaluated and the power quality standard mode are compared and analyzed to construct the power quality grey correlation difference information space.Finally,the target center coefficient and target degree of power quality are calculated to realize the comprehensive evaluation of power quality,and the evaluation grade of power quality monitoring data to be evaluated is obtained.Compared with the evaluation results of the existing literature,the effectiveness of the proposed method is verified,which shows that grey target theory is reasonable in the comprehensive evaluation of power quality. 展开更多
关键词 Smart grid power quality evaluation grey target theory monitoring data
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Safety evaluation of replacement reinforcement quality in abutment contact zones of ultra-high arch dam in first impoundment period based on prototype monitoring 被引量:2
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作者 Bo HU Zhong-ru WU +2 位作者 Guan-biao LIU Bin ZHAO Bo XU 《Water Science and Engineering》 EI CAS 2012年第2期210-218,共9页
Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact z... Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact zones of the Xiaowan ultra-high arch dam. The principles of monitoring layout and design are introduced in detail. Prototype monitoring shows that the increment of the interfacial compressive stress is much larger in the impoundment stage than in the regulating stage. The water pressure and time-effect are two main factors affeeting the interfacial stress. The time-effect is the key factor in the initial impoundment stage, and the water pressure is the key factor after impoundment. The contact properties are significantly improved by grouting. This study shows that there are three typical stages in the joint opening hydrographs, namely the compression stage, opening stage, and stable stage. There is a nonlinear relationship between the joint opening and temperature, which can be well described by the S-function. In conclusion, the reinforcement effect is satisfying, and the abutment is safe. 展开更多
关键词 ultra-high arch dam prototype monitoring compressive stress joint opening safety evaluation
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Individual aircraft life monitoring: An engineering approach for fatigue damage evaluation 被引量:5
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作者 Rui JIAO Xiaofan HE Yuhai LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第4期727-739,共13页
Individual aircraft life monitoring is required to ensure safety and economy of aircraft structure, and fatigue damage evaluation based on collected operational data of aircraft is an integral part of it. To improve t... Individual aircraft life monitoring is required to ensure safety and economy of aircraft structure, and fatigue damage evaluation based on collected operational data of aircraft is an integral part of it. To improve the accuracy and facilitate the application, this paper proposes an engineering approach to evaluate fatigue damage and predict fatigue life for critical structures in fatigue monitoring. In this approach, traditional nominal stress method is applied to back calculate the S-N curve parameters of the realistic structure details based on full-scale fatigue test data. Then the S-N curve and Miner's rule are adopted in damage estimation and fatigue life analysis for critical locations under individual load spectra. The relationship between relative small crack length and fatigue life can also be predicted with this approach. Specimens of 7 B04-T74 aluminum alloy and TA15 M titanium alloy are fatigue tested under two types of load spectra, and there is a good agreement between the experimental results and analysis results. Furthermore, the issue concerning scatter factor in individual aircraft damage estimation is also discussed. 展开更多
关键词 Fatigue damage Fatigue monitoring Fatigue test Scatter factor S-N curve
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