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基于DAS-VMD的甲烷/一氧化碳痕量气体同步监测及噪声抑制方法
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作者 邵昊 袁玉洁 +2 位作者 王凯 张贝 黎奉标 《中国安全生产科学技术》 北大核心 2025年第10期88-95,共8页
为提高煤矿有毒有害气体CH_(4)和CO的实时动态监测能力,基于直接激光吸收光谱(DAS)与变分模态分解法(VMD),研究CH_(4)和CO双组份气体同步在线监测系统,并进行试验验证。针对CH_(4)和CO痕量气体,选用中心波长为1653.4 nm和2325.2 nm的2... 为提高煤矿有毒有害气体CH_(4)和CO的实时动态监测能力,基于直接激光吸收光谱(DAS)与变分模态分解法(VMD),研究CH_(4)和CO双组份气体同步在线监测系统,并进行试验验证。针对CH_(4)和CO痕量气体,选用中心波长为1653.4 nm和2325.2 nm的2台分布式反馈激光器,采用时分复用(TDM)技术,构建双组份痕量气体同步在线监测系统,克服双激光器工作时的相互干扰;优化VMD方法,实现信号分解和噪声抑制,提高检测系统的信噪比;搭建煤自燃在线监测实验平台,开展煤自燃长时间的在线监测试验。研究结果表明:降噪后CH_(4)和CO的探测极限分别为9.4×10^(-6)%与9.9×10^(-6)%,CH_(4)和CO检测极限降幅为38.4%,39.2%;所构建系统在煤自燃过程中对CH_(4)和CO体积分数变化具有良好的跟踪能力与检测可靠性。研究结果可为煤矿灾害气体的高精度、高稳定性实时监测提供可靠的技术手段,提高煤自燃早期预警能力。 展开更多
关键词 直接激光吸收光谱(das) 变分模态分解法(VMD) 甲烷 一氧化碳 痕量气体 噪声抑制
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DAS28对应关节高频超声评分与类风湿性关节炎病情活动程度的关系及临床意义
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作者 苏龙彪 钟琴 《影像研究与医学应用》 2025年第2期49-51,54,共4页
目的:探讨28关节疾病活动评分(DAS28)对应关节的高频超声评分与类风湿性关节炎(RA)病情活动程度的关系及临床意义。方法:选取2021年9月—2024年1月就诊于高州市人民医院的RA患者123例,根据DAS28将患者分为缓解组(25例)、活动组(98例)。... 目的:探讨28关节疾病活动评分(DAS28)对应关节的高频超声评分与类风湿性关节炎(RA)病情活动程度的关系及临床意义。方法:选取2021年9月—2024年1月就诊于高州市人民医院的RA患者123例,根据DAS28将患者分为缓解组(25例)、活动组(98例)。比较两组的一般资料、临床资料和高频超声评分,分析高频超声评分与RA病情活动程度的关系及临床意义。结果:两组性别、体质量指数、发病关节比较,差异无统计学意义(P>0.05);活动组年龄、C反应蛋白(CRP)、血沉(ESR)、骨侵蚀评分、关节积液评分、滑膜内血流信号评分、滑膜厚度评分均高于缓解组,病程长于缓解组,差异有统计学意义(P<0.05);经Pearson相关性分析,骨侵蚀、关节积液、滑膜内血流信号、滑膜厚度评分与RA病情活动程度呈正相关(P<0.05);骨侵蚀、关节积液、滑膜内血流信号、滑膜厚度评分联合诊断RA的AUC为0.896,灵敏度为92.54%,优于各指标单独预测,差异有统计学意义(P<0.05)。结论:高频超声评分与RA病情活动程度呈正相关,且高频超声评分联合诊断RA患者病情活动程度的灵敏度好,临床应用价值也较高。 展开更多
关键词 类风湿性关节炎 das28 高频超声评分 病情活动程度
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基于ResNet-UNet模型的DAS矸石浆体充填堵管监测技术
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作者 柴敬 王梓名 +7 位作者 马晨阳 张丁丁 李至 周森 秋丰岐 吴玉意 冀汶莉 赵鹏翔 《西安科技大学学报》 北大核心 2025年第4期650-662,共13页
煤矸石浆体输送管道在输送过程中易产生堵塞、腐蚀等多种问题。目前针对浆体管道输送中存在的堵塞问题,精准定位仍面临着巨大挑战。基于此,提出了一种以分布式声波传感技术(DAS)为监测手段,结合图像降噪与ResNet-UNet复合网络对堵塞点... 煤矸石浆体输送管道在输送过程中易产生堵塞、腐蚀等多种问题。目前针对浆体管道输送中存在的堵塞问题,精准定位仍面临着巨大挑战。基于此,提出了一种以分布式声波传感技术(DAS)为监测手段,结合图像降噪与ResNet-UNet复合网络对堵塞点位进行监测和识别的方法;为评估所提出的技术方案,建立了15.14 m的环管模型,并进行注浆堵塞模拟试验。结果表明:相比于传统的UNet及ResNet网络,ResNet-UNet网络模型可在有效避免梯度爆炸问题的基础上,较为精准地对堵塞点位图像进行识别,堵塞点定位的准确率为97.83%,精确率为97.76%,召回率为94.80%,F1分数为0.958 9。该研究在全覆盖式监测矸石输送管道的基础上,有效解决了DAS传感监测时,由于其高灵敏度所带来的噪声处理难题,较为精确地实现了堵塞点的定位效果,研究为矸石浆体输送管道监测及堵塞点的定位问题提供了智能化的解决方案。 展开更多
关键词 分布式声波传感技术 矸石浆体管道输送 降噪算法 ResNet-UNet模型 图像识别 堵塞定位
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带Markov拓扑的多智能体系统在DoS攻击和DAs下的均方一致性
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作者 陈钊杰 叶钊显 +2 位作者 高钰博 周霞 马忠军 《应用数学》 北大核心 2025年第3期670-680,共11页
研究具有Markov切换拓扑的非线性多智能体系统在遭受拒绝服务(DoS)攻击和欺骗攻击(DAs)下的领导-跟随均方一致性问题.采用Bernoulli随机变量序列来描述多智能体系统随机受到DoS攻击或DAs.当系统遭受网络攻击时,多智能体之间的网络通讯... 研究具有Markov切换拓扑的非线性多智能体系统在遭受拒绝服务(DoS)攻击和欺骗攻击(DAs)下的领导-跟随均方一致性问题.采用Bernoulli随机变量序列来描述多智能体系统随机受到DoS攻击或DAs.当系统遭受网络攻击时,多智能体之间的网络通讯拓扑的参数和结构发生随机改变,将其建模为Markov切换拓扑.基于随机微分方程和分布式控制理论,应用随机分析方法和Lyapunov直接法,得到系统实现领导-跟随均方一致的充分条件,并通过数值仿真验证了所得结果的正确性和方法的有效性. 展开更多
关键词 非线性多智能体系统 DOS攻击 das Markov切换拓扑 均方一致性
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基于分布式光纤声波传感技术(DAS)的地下管道、隧道侵入监测方法研究 被引量:3
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作者 曹鹏涛 韦义师 +1 位作者 李轶 吴奇 《物探化探计算技术》 2025年第1期104-116,共13页
地铁隧道沿线入侵事件造成地铁线路变形破坏,地下管道沿线人为破坏、野蛮施工引发安全事故与财产损失,有必要在隧道沿线与地下管道沿线进行监测与预警,及时发现入侵破坏处,进行阻止或者及时开展补救维修降低事故损失。分布式光纤声波传... 地铁隧道沿线入侵事件造成地铁线路变形破坏,地下管道沿线人为破坏、野蛮施工引发安全事故与财产损失,有必要在隧道沿线与地下管道沿线进行监测与预警,及时发现入侵破坏处,进行阻止或者及时开展补救维修降低事故损失。分布式光纤声波传感(DAS)技术,具有动态在线监测、大范围密集测量、方便布设免维护等独特优势。通过在地下轨道交通、地下管道沿线布设分布式光纤,采用DAS技术对光纤沿线外界扰动进行监测,针对传统的时频分析算法不适用分析DAS信号,笔者采用基于优化S变换的时频分析方法,将DAS信号变换到时间-频率域,根据不同振动信号的时频特征差异,在时间频率域对不同振动信号进行分类识别、精确定位,并对超过阈值的侵入信号进行预警。通过数值模拟分析以及实际地铁线路区间DAS监测实验,结果表明基于优化S变换的DAS监测方法技术,对不同主频振动信号具有较强识别监测能力,并且具有监测距离长、响应及时等特点,可以实现长距离、大范围密集测量、动态、实时监测预警,为城市地下管道、地下轨道交通沿线监测提供了一种快速准确的解决方案。 展开更多
关键词 分布式光纤声波传感(das) 监测预警 时频分析
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复杂黄土塬区DAS井地联采解释技术及应用
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作者 陈策 陈浩林 +4 位作者 李嘉宁 王学刚 周丽萍 李相文 安树杰 《石油地球物理勘探》 北大核心 2025年第5期1234-1246,共13页
复杂黄土塬对地震波能量的吸收衰减一直是地球物理学者关注的焦点之一,其地震资料分辨率和信噪比提升困难,难以满足老油区油藏精细描述和剩余油挖潜的需求。为此,在应用常规井中地震和地面地震资料解释技术的基础上,综合利用DAS 3D-VSP... 复杂黄土塬对地震波能量的吸收衰减一直是地球物理学者关注的焦点之一,其地震资料分辨率和信噪比提升困难,难以满足老油区油藏精细描述和剩余油挖潜的需求。为此,在应用常规井中地震和地面地震资料解释技术的基础上,综合利用DAS 3D-VSP成像数据,开展面向油藏精细描述的配套解释技术研究,形成了基于井地联采数据的解释性预处理、储层预测、缝网刻画等技术系列。在鄂尔多斯盆地东部某区块,应用基于井地联采数据的叠后自适应频谱拓宽高分辨率处理技术,地震资料主频可提高5 Hz,频带拓宽25 Hz;基于DAS 3DVSP数据的波形指示薄储层反演技术能够准确识别厚度3~5 m单砂体,各层系验证井综合符合率达到86.32%;基于倾角方位扫描约束的缝网识别技术实现了低序级断裂—缝网的有效预测;基于DAS井地联采数据,形成了一套井地+井震油藏精细描述技术,储层刻画精度提升15%。应用结果表明,基于DAS井地联合勘探的配套技术具有推广价值。 展开更多
关键词 复杂黄土塬 das井地联合勘探 3D-VSP 自适应频谱拓宽 波形指示反演 缝网预测
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Enhancing subsurface seismic profiling with distributed acoustic sensing and optimization algorithms
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作者 Jing Wang Hong-Hu Zhu +4 位作者 Gang Cheng Tao Wang Xu-Long Gong Dao-Yuan Tan Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3632-3643,共12页
The distribution of shear-wave velocities in the subsurface is generally used to assess the potential forseismic liquefaction and soil amplification effects and to classify seismic sites. Newly developeddistributed ac... The distribution of shear-wave velocities in the subsurface is generally used to assess the potential forseismic liquefaction and soil amplification effects and to classify seismic sites. Newly developeddistributed acoustic sensing (DAS) technology enables estimation of the shear-wave distribution as ahigh-density seismic observation system. This technology is characterized by low maintenance costs,high-resolution outputs, and real-time data transmission capabilities, albeit with the challenge ofmanaging massive data generation. Rapid and efficient interpretation of data is the key to advancingapplication of the DAS technology. In this study, field tests were carried out to record ambient noise overa short period using DAS technology, from which the surface-wave dispersion curves were extracted. Inorder to reduce the influence of directional effects on the results, an unsupervised clustering method isused to select appropriate clusters to extract the Green's function. A combination of a genetic algorithmand Monte Carlo (GA-MC) simulation is proposed to invert the subsurface velocity structure. Thestratigraphic profiles obtained by the GA-MC method are in agreement with the borehole profiles.Compared to other methods, the proposed optimization method not only improves the solution qualitybut also reduces the solution time. 展开更多
关键词 Shallow subsurface velocity Site classification Ambient noise imaging Distributed acoustic sensing(das) Genetic algorithms and Monte Carlo simulation
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MXene-based thermoelectric fabric integrated with temperature and strain sensing for health monitoring 被引量:1
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作者 Jun Peng Fangqing Ge +4 位作者 Weiyi Han Tao Wu Jinglei Tang Yuning Li Chaoxia Wang 《Journal of Materials Science & Technology》 2025年第9期272-280,共9页
Wearable thermoelectric devices hold significant promise in the realm of self-powered wearable electron-ics,offering applications in energy harvesting,movement tracking,and health monitoring.Nevertheless,developing th... Wearable thermoelectric devices hold significant promise in the realm of self-powered wearable electron-ics,offering applications in energy harvesting,movement tracking,and health monitoring.Nevertheless,developing thermoelectric devices with exceptional flexibility,enduring thermoelectric stability,multi-functional sensing,and comfortable wear remains a challenge.In this work,a stretchable MXene-based thermoelectric fabric is designed to accurately discern temperature and strain stimuli.This is achieved by constructing an adhesive polydopamine(PDA)layer on the nylon fabric surface,which facilitates the subsequent MXene attachment through hydrogen bonding.This fusion results in MXene-based thermo-electric fabric that excels in both temperature sensing and strain sensing.The resultant MXene-based thermoelectric fabric exhibits outstanding temperature detection capability and cyclic stability,while also delivering excellent sensitivity,rapid responsiveness(60 ms),and remarkable durability in strain sens-ing(3200 cycles).Moreover,when affixed to a mask,this MXene-based thermoelectric fabric utilizes the temperature difference between the body and the environment to harness body heat,converting it into electrical energy and accurately discerning the body’s respiratory rate.In addition,the MXene-based ther-moelectric fabric can monitor the state of the body’s joint through its own deformation.Furthermore,it possesses the capability to convert solar energy into heat.These findings indicate that MXene-based ther-moelectric fabric holds great promise for applications in power generation,motion tracking,and health monitoring. 展开更多
关键词 Mxene thermoelectric fabric Temperature sensing Strain sensing Energy harvesting
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基于DTS与DAS测试的储气库环空起压井漏点判断方法实践
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作者 乔松涛 刘海波 +2 位作者 胡建合 李筱靓 王世鹏 《石油化工设备技术》 2025年第4期61-66,I0004,共7页
某储气库注采井投入生产后经历多周期注采,长期承受交变载荷变化影响,其油管与油套环空、油套与技套环空、技套与表套环空可能会出现起压现象;同时,各级环空长期承受高压,易破坏井筒密封完整性,造成注入天然气窜漏,影响井控安全和正常... 某储气库注采井投入生产后经历多周期注采,长期承受交变载荷变化影响,其油管与油套环空、油套与技套环空、技套与表套环空可能会出现起压现象;同时,各级环空长期承受高压,易破坏井筒密封完整性,造成注入天然气窜漏,影响井控安全和正常生产。造成各级环空起压的原因多达十几种,该储气库目前仅依靠注采井压力、温度,以及环空保护液液面监测数据无法准确判断泄漏点和具体泄漏途径。为了精准治理和有效管控环空起压情况,引入基于DTS与DAS技术的光纤测试方法。文章介绍了DTS与DAS光纤测试技术原理,以及该技术在几口典型井中的应用情况。应用结果显示,利用该技术可有效判断漏点位置,为下一步对症治理环空起压现象提供支持,对其他储气库环空起压井的治理也有一定的参考意义。 展开更多
关键词 储气库 环空起压 光纤 漏点 DTS das
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IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data 被引量:1
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作者 Zhe Li Yun Liang +1 位作者 Jinyu Wang Yang Gao 《Computers, Materials & Continua》 SCIE EI 2025年第1期1171-1192,共22页
Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power outages.Existing early warning methods of iced tran... Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power outages.Existing early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false alarms.To address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather forecast.Initially,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused data.Furthermore,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network model.Subsequently,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this coefficient.Finally,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios. 展开更多
关键词 Optical fiber sensing multi-source data fusion early warning of galloping time series data IOT adaptive weighted learning irregular time series perception closed-loop attention mechanism
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A Flexible‑Integrated Multimodal Hydrogel‑Based Sensing Patch 被引量:1
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作者 Peng Wang Guoqing Wang +4 位作者 Guifen Sun Chenchen Bao Yang Li Chuizhou Meng Zhao Yao 《Nano-Micro Letters》 2025年第7期107-125,共19页
Sleep monitoring is an important part of health management because sleep quality is crucial for restoration of human health.However,current commercial products of polysomnography are cumbersome with connecting wires a... Sleep monitoring is an important part of health management because sleep quality is crucial for restoration of human health.However,current commercial products of polysomnography are cumbersome with connecting wires and state-of-the-art flexible sensors are still interferential for being attached to the body.Herein,we develop a flexible-integrated multimodal sensing patch based on hydrogel and its application in unconstraint sleep monitoring.The patch comprises a bottom hydrogel-based dualmode pressure–temperature sensing layer and a top electrospun nanofiber-based non-contact detection layer as one integrated device.The hydrogel as core substrate exhibits strong toughness and water retention,and the multimodal sensing of temperature,pressure,and non-contact proximity is realized based on different sensing mechanisms with no crosstalk interference.The multimodal sensing function is verified in a simulated real-world scenario by a robotic hand grasping objects to validate its practicability.Multiple multimodal sensing patches integrated on different locations of a pillow are assembled for intelligent sleep monitoring.Versatile human–pillow interaction information as well as their evolution over time are acquired and analyzed by a one-dimensional convolutional neural network.Track of head movement and recognition of bad patterns that may lead to poor sleep are achieved,which provides a promising approach for sleep monitoring. 展开更多
关键词 Multimodal sensing Proximity sensor Pressure sensor Temperature sensor Electrospun nanofibers
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Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator
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作者 CHEN Jinyou HU Wei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期240-245,共6页
To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is employed.One of the essential goals is to examine the mechanical character... To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is employed.One of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole actuator.The functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of bending.The experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and width.When the voltage reaches 0.8 V,the bending speed of the actuator tends to be stable.Finally,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper. 展开更多
关键词 conductive polymer POLYPYRROLE mechanical characteristics actuators sensing characteristics
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Multi-scale feature fusion optical remote sensing target detection method 被引量:1
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作者 BAI Liang DING Xuewen +1 位作者 LIU Ying CHANG Limei 《Optoelectronics Letters》 2025年第4期226-233,共8页
An improved model based on you only look once version 8(YOLOv8)is proposed to solve the problem of low detection accuracy due to the diversity of object sizes in optical remote sensing images.Firstly,the feature pyram... An improved model based on you only look once version 8(YOLOv8)is proposed to solve the problem of low detection accuracy due to the diversity of object sizes in optical remote sensing images.Firstly,the feature pyramid network(FPN)structure of the original YOLOv8 mode is replaced by the generalized-FPN(GFPN)structure in GiraffeDet to realize the"cross-layer"and"cross-scale"adaptive feature fusion,to enrich the semantic information and spatial information on the feature map to improve the target detection ability of the model.Secondly,a pyramid-pool module of multi atrous spatial pyramid pooling(MASPP)is designed by using the idea of atrous convolution and feature pyramid structure to extract multi-scale features,so as to improve the processing ability of the model for multi-scale objects.The experimental results show that the detection accuracy of the improved YOLOv8 model on DIOR dataset is 92%and mean average precision(mAP)is 87.9%,respectively 3.5%and 1.7%higher than those of the original model.It is proved the detection and classification ability of the proposed model on multi-dimensional optical remote sensing target has been improved. 展开更多
关键词 multi scale feature fusion optical remote sensing feature map improve target detection ability optical remote sensing imagesfirstlythe target detection feature fusionto enrich semantic information spatial information
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A phenylphenthiazide anchored Tb(Ⅲ)-cyclen complex for fluorescent turn-on sensing of ClO^(-) 被引量:1
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作者 Ya-Ping Liu Zhi-Rong Gui +4 位作者 Zhen-Wen Zhang Sai-Kang Wang Wei Lang Yanzhu Liu Qian-Yong Cao 《Chinese Chemical Letters》 2025年第2期269-273,共5页
A phenylphenothiazine anchored Tb(Ⅲ)-cyclen complex PTP-Cy-Tb for hypochlorite ion(ClO^(-))detection has been designed and prepared.PTP-Cy-Tb shows a weak Tb-based emission with AIE-characteristics in aqueous solutio... A phenylphenothiazine anchored Tb(Ⅲ)-cyclen complex PTP-Cy-Tb for hypochlorite ion(ClO^(-))detection has been designed and prepared.PTP-Cy-Tb shows a weak Tb-based emission with AIE-characteristics in aqueous solutions.After addition of ClO^(-),the fluorescence of PTP-Cy-Tb gives a large enhancement for oxidization the thioether to sulfoxide group.The detection limit of PTP-Cy-Tb toward ClO^(-)is as low as 8.85 nmol/L.The sensing mechanism was detailedly investigated by time of flight mass spectrometer(TOF-MS),Fourier transform infrared spectroscopy(FT-IR)and density functional theory(DFT)calculation.In addition,PTP-Cy-Tb has been successfully used for on-site and real-time detection of ClO^(-)in real water samples by using the smartphone-based visualization method and test strips. 展开更多
关键词 Phenylphenothiazine Tb(III)complex AIE Hypochlorite ion sensing
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Coupling Multi-Source Satellite Remote Sensing and Meteorological Data to Discriminate Yellow Rust and Fusarium Head Blight in Winter Wheat 被引量:1
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作者 Qi Sheng Huiqin Ma +4 位作者 Jingcheng Zhang Zhiqin Gui Wenjiang Huang Dongmei Chen Bo Wang 《Phyton-International Journal of Experimental Botany》 2025年第2期421-440,共20页
Yellow rust(Puccinia striiformis f.sp.Tritici,YR)and fusarium head blight(Fusarium graminearum,FHB)are the two main diseases affecting wheat in the main grain-producing areas of East China,which is common for the two ... Yellow rust(Puccinia striiformis f.sp.Tritici,YR)and fusarium head blight(Fusarium graminearum,FHB)are the two main diseases affecting wheat in the main grain-producing areas of East China,which is common for the two diseases to appear simultaneously in some main production areas.It is necessary to discriminate wheat YR and FHB at the regional scale to accurately locate the disease in space,conduct detailed disease severity monitoring,and scientific control.Four images on different dates were acquired from Sentinel-2,Landsat-8,and Gaofen-1 during the critical period of winter wheat,and 22 remote sensing features that characterize the wheat growth status were then calculated.Meanwhile,6 meteorological parameters that reflect the wheat phenological information were also obtained by combining the site meteorological data and spatial interpolation technology.Then,the principal components(PCs)of comprehensive remote sensing and meteorological features were extracted with principal component analysis(PCA).The PCs-based discrimination models were established to map YR and FHB damage using the random forest(RF)and backpropagation neural network(BPNN).The models’performance was verified based on the disease field truth data(57 plots during the filling period)and 5-fold cross-validation.The results revealed that the PCs obtained after PCA dimensionality reduction outperformed the initial features(IFs)from remote sensing and meteorology in discriminating between the two diseases.Compared to the IFs,the average area under the curve for both micro-average and macro-average ROC curves increased by 0.07 in the PCs-based RF models and increased by 0.16 and 0.13,respectively,in the PCs-based BPNN models.Notably,the PCs-based BPNN discrimination model emerged as the most effective,achieving an overall accuracy of 83.9%.Our proposed discrimination model for wheat YR and FHB,coupled with multi-source remote sensing images and meteorological data,overcomes the limitations of a single-sensor and single-phase remote sensing information in multiple stress discrimination in cloudy and rainy areas.It performs well in revealing the damage spatial distribution of the two diseases at a regional scale,providing a basis for detailed disease severity monitoring,and scientific prevention and control. 展开更多
关键词 Winter wheat yellow rust(YR) fusarium head blight(FHB) DISCRIMINATION remote sensing and meteorology
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Praseodymium-organic framework with 4,4′-oxybis(benzoic acid):Rare broken layer structure,antibacterial activity,and sensing for Cd^(2+)ions
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作者 CUI Peipei ZHENG Yawen +2 位作者 LI Pan GUAN Peiyan QIAN Zhaohong 《无机化学学报》 北大核心 2025年第8期1641-1649,共9页
A novel 3D metal-organic framework(MOF)[Pr_(2)(L)_(3)(H_(2)O)5·H_(2)O]n(Pr-1),(H_(2)L=4,4'-oxybis(benzoic acid))with a rare structure of broken layer net,was constructed under the condition of solvothermal sy... A novel 3D metal-organic framework(MOF)[Pr_(2)(L)_(3)(H_(2)O)5·H_(2)O]n(Pr-1),(H_(2)L=4,4'-oxybis(benzoic acid))with a rare structure of broken layer net,was constructed under the condition of solvothermal synthesis.The struc-ture and crystal net were analyzed and characterized.This rod net of Pr-1 is new to both RCSR and ToposPro data-bases,and is named as rn-12 as suggested.Due to the luminescent properties of H_(2)L and Pr(Ⅲ),the solid-state fluo-rescence property and sensing performance(solvents and metal ions)of Pr-1 were investigated.The sensing experi-ments indicated that Pr-1 could act as a fluorescence sensor to detect Cd^(2+)ions with good sensitivity.In addition,antibacterial activities show that Pr-1 exhibited stronger antibacterial activity against Escherichia coli(E.coli),Staphylococcus aureus(S.aureus),and Bacillus subtilis(B.subtilis)compared to synthetic materials. 展开更多
关键词 dicarboxylate ligand crystal net luminescence sensing antibacterial activity
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ECD-Net: An Effective Cloud Detection Network for Remote Sensing Images
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作者 Hui Gao Xianjun Du 《Journal of Computer and Communications》 2025年第1期1-14,共14页
Cloud detection is a critical preprocessing step in remote sensing image processing, as the presence of clouds significantly affects the accuracy of remote sensing data and limits its applicability across various doma... Cloud detection is a critical preprocessing step in remote sensing image processing, as the presence of clouds significantly affects the accuracy of remote sensing data and limits its applicability across various domains. This study presents an enhanced cloud detection method based on the U-Net architecture, designed to address the challenges of multi-scale cloud features and long-range dependencies inherent in remote sensing imagery. A Multi-Scale Dilated Attention (MSDA) module is introduced to effectively integrate multi-scale information and model long-range dependencies across different scales, enhancing the model’s ability to detect clouds of varying sizes. Additionally, a Multi-Head Self-Attention (MHSA) mechanism is incorporated to improve the model’s capacity for capturing finer details, particularly in distinguishing thin clouds from surface features. A multi-path supervision mechanism is also devised to ensure the model learns cloud features at multiple scales, further boosting the accuracy and robustness of cloud mask generation. Experimental results demonstrate that the enhanced model achieves superior performance compared to other benchmarked methods in complex scenarios. It significantly improves cloud detection accuracy, highlighting its strong potential for practical applications in cloud detection tasks. 展开更多
关键词 Deep Learning Remote sensing Cloud Detection MSDA MHSA
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Web-Based Platform and Remote Sensing Technology for Monitoring Mangrove Ecosystem
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作者 Evelyn Anthony Rodriguez John Edgar Sualog Anthony +2 位作者 Randy Anthony Quitain Wilma Cledera Delos Santos Ernesto Jr. Benda Rodriguez 《Open Journal of Ecology》 2025年第1期1-10,共10页
Remote sensing and web-based platforms have emerged as vital tools in the effective monitoring of mangrove ecosystems, which are crucial for coastal protection, biodiversity, and carbon sequestration. Utilizing satell... Remote sensing and web-based platforms have emerged as vital tools in the effective monitoring of mangrove ecosystems, which are crucial for coastal protection, biodiversity, and carbon sequestration. Utilizing satellite imagery and aerial data, remote sensing allows researchers to assess the health and extent of mangrove forests over large areas and time periods, providing insights into changes due to environmental stressors like climate change, urbanization, and deforestation. Coupled with web-based platforms, this technology facilitates real-time data sharing and collaborative research efforts among scientists, policymakers, and conservationists. Thus, there is a need to grow this research interest among experts working in this kind of ecosystem. The aim of this paper is to provide a comprehensive literature review on the effective role of remote sensing and web-based platform in monitoring mangrove ecosystem. The research paper utilized the thematic approach to extract specific information to use in the discussion which helped realize the efficiency of digital monitoring for the environment. Web-based platforms and remote sensing represent a powerful tool for environmental monitoring, particularly in the context of forest ecosystems. They facilitate the accessibility of vital data, promote collaboration among stakeholders, support evidence-based policymaking, and engage communities in conservation efforts. As experts confront the urgent challenges posed by climate change and environmental degradation, leveraging technology through web-based platforms is essential for fostering a sustainable future for the forests of the world. 展开更多
关键词 Mangrove Ecosystems MONITORING Remote sensing Web-Based Platform
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Ultrastrong silk fabric ionogel-sensor for strain/temperature/tactile multi-mode sensing
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作者 Shu Wang Jiangling Ning +9 位作者 Jianyu Pu Changjie Wei Yuping Yuan Songqi Yao Yuantao Zhang Ziwen Jing Chenxing Xiang Xinglong Gong Zhi Li Ning Hu 《Nano Materials Science》 2025年第3期316-325,共10页
Ionogels have demonstrated substantial applications in smart wearable systems,soft robotics,and biomedical engineering due to the exceptional ionic conductivity and optical transparency.However,achieving ionogels with... Ionogels have demonstrated substantial applications in smart wearable systems,soft robotics,and biomedical engineering due to the exceptional ionic conductivity and optical transparency.However,achieving ionogels with desirable mechanical properties,environmental stability,and multi-mode sensing remains challenging.Here,we propose a simple strategy for the fabrication of multifunctional silk fabric-based ionogels(BSFIGs).The resulting fabric ionogels exhibits superior mechanical properties,with high tensile strength(11.3 MPa)and work of fracture(2.53 MJ/m^(3)).And its work of fracture still has 1.42 MJ/m^(3)as the notch increased to 50%,indicating its crack growth insensitivity.These ionogels can be used as sensors for strain,temperature,and tactile multimode sensing,demonstrating a gauge factor of 1.19 and a temperature coefficient of resistance of3.17/℃^(-1).Furthermore,these ionogels can be used for the detection of different roughness and as touch screens.The ionogels also exhibit exceptional optical transmittance and environmental stability even at80℃.Our scalable fabrication process broadens the application potential of these multifunctional ionogels in diverse fields,from smart systems to extreme environments. 展开更多
关键词 Silk fabric ionogel Mechanical properties Strain sensing Temperature sensing Tactile sensing
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Block sparse compressed sensing with frames:Null space property and l_(2)/l_(q)(0
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作者 WU Fengong ZHONG Penghong QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第3期173-182,共10页
This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based ... This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based on the dictionary D.We establish that matrices adhering to the block D-NSP_(q)condition are both necessary and sufficient for the exact recovery of block sparse signals via l_(2)/l_(q)-synthesis.Additionally,this condition is essential for the stable recovery of signals that are block-compressible with respect to D.This D-NSP_(q)property is identified as the first complete condition for successful signal recovery using l_(2)/l_(q)-synthesis.Furthermore,we assess the theoretical efficacy of the l2/lq-synthesis method under conditions of measurement noise. 展开更多
关键词 Compressed sensing block sparse l2/lq-synthesis method null space property
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