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Research and application of real-time monitoring and early warning thresholds for multi-temporal agricultural products information 被引量:3
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作者 XU Shi-wei WANG Yu +1 位作者 WANG Sheng-wei LI Jian-zheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第10期2582-2596,共15页
Monitoring and early warning is an important means to effectively prevent risks in agricultural production,consumption and price.In particular,with the change of modes of national administration against the background... Monitoring and early warning is an important means to effectively prevent risks in agricultural production,consumption and price.In particular,with the change of modes of national administration against the background of big data,improving the capacity to monitor agricultural products is of great significance for macroeconomic decision-making.Agricultural product information early warning thresholds are the core of agricultural product monitoring and early warning.How to appropriately determine the early warning thresholds of multi-temporal agricultural product information is a key question to realize real-time and dynamic monitoring and early warning.Based on the theory of abnormal fluctuation of agricultural product information and the research of substantive impact on the society,this paper comprehensively discussed the methods to determine the thresholds of agricultural product information fluctuation in different time dimensions.Based on the data of the National Bureau of Statistics of China(NBSC)and survey data,this paper used a variety of statistical methods to determine the early warning thresholds of the production,consumption and prices of agricultural products.Combined with Delphi expert judgment correction method,it finally determined the early warning thresholds of agricultural product information in multiple time,and carried out early warning analysis on the fluctuation of agricultural product monitoring information in 2018.The results show that:(1)the daily,weekly and monthly monitoring and early warning thresholds of agricultural products play an important early warning role in monitoring abnormal fluctuations with agricultural products;(2)the multitemporal monitoring and early warning thresholds of agricultural product information identified by the research institute can provide effective early warning on current abnormal fluctuation of agricultural product information,provide a benchmarking standard for China's agricultural production,consumption and price monitoring and early warning at the national macro level,and further improve the application of China's agricultural product monitoring and early warning. 展开更多
关键词 agricultural product information monitoring and early warning THRESHOLD MULTI-TEMPORAL real-time dynamics
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Research on Technology Early-Warning System Based on Dynamic Information Monitoring
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作者 汪雪锋 朱东华 +1 位作者 刘嵩 刘佳 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期121-126,共6页
Relying on the advanced information technologies, such as information monitoring, data mining, natural language processing etc., the dynamic technology early-warning system is constructed. The system consists of techn... Relying on the advanced information technologies, such as information monitoring, data mining, natural language processing etc., the dynamic technology early-warning system is constructed. The system consists of technology information automatic retrieval, technology information monitoring, technology threat evaluation, and crisis response and management subsystem, which implements uninterrupted dynamic monitoring, trace and crisis early-warning to the specific technology. Empirical study testifies that the system improves the accuracy, timeliness and reliability of technology early-warning. 展开更多
关键词 technology early-warning system information monitoring dynamic retrieval technology threatevaluation crisis response and management
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Designing a Teaching Website for Early Warning Technology Support Specialty Based on Information Architecture
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作者 Xiaobin Huang Yan Zhang 《Journal of Contemporary Educational Research》 2022年第1期7-11,共5页
With the advancement of education informatization,learning through the internet has become a very important approach.Existing teaching websites generally have problems such as low accuracy of information grouping and ... With the advancement of education informatization,learning through the internet has become a very important approach.Existing teaching websites generally have problems such as low accuracy of information grouping and obvious disconnection between the navigation system and content.Based on information architecture,a teaching website for early warning technical support specialty is designed in this paper from four aspects:content organization,identification,navigation,and interaction.The unification of information processing and information requirements is achieved using this method,which improves the quality of professional course construction for early warning technology support specialty. 展开更多
关键词 information architecture early warning technology support specialty Website design
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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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Development and Application of Meteorological Disaster Monitoring and Early Warning Platform for Characteristic Agriculture in Huzhou City Based on GIS 被引量:1
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作者 Bin WU Yanfang LI Shuangxi LIU 《Asian Agricultural Research》 2017年第1期50-52,56,共4页
Based on the needs of characteristic agricultural production for meteorological services in Huzhou City,we use C# programming language to develop the meteorological disaster monitoring and early warning platform for c... Based on the needs of characteristic agricultural production for meteorological services in Huzhou City,we use C# programming language to develop the meteorological disaster monitoring and early warning platform for characteristic agriculture in Huzhou City. This platform integrates the functions of meteorological and agricultural information monitoring,disaster identification and early warning,fine weather forecast product display,and data query and management,which effectively enhances the capacity of meteorological disaster monitoring and early warning for characteristic agriculture in Huzhou City,and provides strong technical support for the meteorological and agricultural departments in the agricultural meteorological services. 展开更多
关键词 Characteristic agriculture Meteorological and agricultural information monitoring Fine weather forecast products Meteorological disaster monitoring and early warning
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Fault Warning of Satellite Momentum Wheels With a Lightweight Transformer Improved by FastDTW
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作者 Yiming Gao Shi Qiu +2 位作者 Ming Liu Lixian Zhang Xibin Cao 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期539-549,共11页
The momentum wheel assumes a dominant role as an inertial actuator for satellite attitude control systems.Due to the effects of structural aging and external interference,the momentum wheel may experience the gradual ... The momentum wheel assumes a dominant role as an inertial actuator for satellite attitude control systems.Due to the effects of structural aging and external interference,the momentum wheel may experience the gradual emergence of irreversible faults.These fault features will become apparent in the telemetry signal transmitted by the momentum wheel.This paper introduces ADTWformer,a lightweight model for long-term prediction of time series,to analyze the time evolution trend and multi-dimensional data coupling mechanism of satellite momentum wheel faults.Moreover,the incorporation of the approximate Markov blanket with the maximum information coefficient presents a novel methodology for performing correlation analysis,providing significant perspectives from a data-centric standpoint.Ultimately,the creation of an adaptive alarm mechanism allows for the successful attainment of the momentum wheel fault warning by detecting the changes in the health status curves.The analysis methodology outlined in this article has exhibited positive results in identifying instances of satellite momentum wheel failure in two scenarios,thereby showcasing considerable promise for large-scale applications. 展开更多
关键词 Approximate Markov blanket fault early warning maximal information coefficient satellite momentum wheel
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An Intelligent Early Warning Method of Press-Assembly Quality Based on Outlier Data Detection and Linear Regression
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作者 XUE Shanliang LI Chen 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第4期597-606,共10页
Focusing on controlling the press-assembly quality of high-precision servo mechanism,an intelligent early warning method based on outlier data detection and linear regression is proposed.Linear regression is used to d... Focusing on controlling the press-assembly quality of high-precision servo mechanism,an intelligent early warning method based on outlier data detection and linear regression is proposed.Linear regression is used to deal with the relationship between assembly quality and press-assembly process,then the mathematical model of displacement-force in press-assembly process is established and a qualified press-assembly force range is defined for assembly quality control.To preprocess the raw dataset of displacement-force in the press-assembly process,an improved local outlier factor based on area density and P weight(LAOPW)is designed to eliminate the outliers which will result in inaccuracy of the mathematical model.A weighted distance based on information entropy is used to measure distance,and the reachable distance is replaced with P weight.Experiments show that the detection efficiency of the algorithm is improved by 5.6 ms compared with the traditional local outlier factor(LOF)algorithm,and the detection accuracy is improved by about 2%compared with the local outlier factor based on area density(LAOF)algorithm.The application of LAOPW algorithm and the linear regression model shows that it can effectively carry out intelligent early warning of press-assembly quality of high precision servo mechanism. 展开更多
关键词 quality early warning outlier data detection linear regression local outlier factor based on area density and P weight(LAOPW) information entropy P weight
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A Personalized Adverse Drug Reaction Early Warning Method Based on Contextual Ontology and Rules Learning
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作者 Haixia Zheng Wei Wei 《Journal of Software Engineering and Applications》 2023年第11期605-621,共17页
Background: The fatality of adverse drug reactions (ADR) has become one of the major causes of the non-natural disease deaths globally, with the issue of drug safety emerging as a common topic of concern. Objective: T... Background: The fatality of adverse drug reactions (ADR) has become one of the major causes of the non-natural disease deaths globally, with the issue of drug safety emerging as a common topic of concern. Objective: The personalized ADR early warning method, based on contextual ontology and rule learning, proposed in this study aims to provide a reference method for personalized health and medical information services. Methods: First, the patient data is formalized, and the user contextual ontology is constructed, reflecting the characteristics of the patient population. The concept of ontology rule learning is then proposed, which is to mine the rules contained in the data set through machine learning to improve the efficiency and scientificity of ontology rule generation. Based on the contextual ontology of ADR, the high-level context information is identified and predicted by means of reasoning, so the occurrence of the specific adverse reaction in patients from different populations is extracted. Results: Finally, using diabetes drugs as an example, contextual information is identified and predicted through reasoning, to mine the occurrence of specific adverse reactions in different patient populations, and realize personalized medication decision-making and early warning of ADR. 展开更多
关键词 Health information Services PERSONALIZED Contextual Ontology Drug Adverse Reaction early warning REASONING
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The Development of Intelligent Operation Method of Urban Public Infrastructure Driven by Accurate Spatio-temporal Information 被引量:5
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作者 Jingyuan JIA Bo WANG 《Journal of Geodesy and Geoinformation Science》 2021年第2期27-35,共9页
Urban public infrastructure is an important basis for urban development.It is of great significance to deepen the research on intelligent management and control of urban public infrastructure.Spatio-temporal informati... Urban public infrastructure is an important basis for urban development.It is of great significance to deepen the research on intelligent management and control of urban public infrastructure.Spatio-temporal information contains the law of state evolution of urban public infrastructure,which is the information base of intelligent control of infrastructure.Due to the needs of operation management and emergency response,efficient sharing and visualization of spatio-temporal information are important research contents of comprehensive management and control of urban public infrastructure.On the basis of summarizing the theoretical research and application in recent years,the basic methods and current situation of the acquisition and analysis of spatio-temporal information,the forecast and early warning,and the intelligent control of urban public infrastructure are reviewed in this paper. 展开更多
关键词 urban public infrastructure satellite navigation system spatio-temporal information forecast and early warning intelligent control
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基于VCW-Informer的天然气压缩机组监测数据预警方法
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作者 姚俊名 梁伟 +3 位作者 郑志明 黄天长 付千郡 廖春燕 《中国安全科学学报》 北大核心 2025年第7期167-175,共9页
为进一步提升天然气压缩机组的早期异常预警能力,基于变分模态分解(VMD)算法、Informer算法、3σ准则判据与Correlation-Weight优化提出一个新的预警方法。基于Informer架构搭建预测模型,利用VMD算法将监测数据分解为不同频率的多维尺... 为进一步提升天然气压缩机组的早期异常预警能力,基于变分模态分解(VMD)算法、Informer算法、3σ准则判据与Correlation-Weight优化提出一个新的预警方法。基于Informer架构搭建预测模型,利用VMD算法将监测数据分解为不同频率的多维尺度特征作为模型输入。在训练过程中,计算各分量特征与原始信号的权重系数来优化调整模型内部参数。并利用预测重构结果与统计分析的3σ判据进一步提升预警性能。采集现场压缩机组2段正常与异常的压差监测数据进行实例验证,试验结果表明:相比于其他预测方法,所提出的预警方法具有最小的预测误差,正常箱体压差的预测结果同比降低66.67%~71.43%(均方误差(MSE)),36.67%~45.45%(平均绝对误差(MAE)),40.17%~45.42%(均方根误差(RMSE)),36.57%~45.72%(平均绝对百分比误差(MAPE));异常进气压差的预测结果同比降低64.43%~71.12%(MSE),44.02%~52.27%(MAE),40.36%~45.53%(RMSE),37.24%~47.79%(MAPE)。该方法在细节特征与趋势特征上具有更好的预测精度,在测试集中能提前60 min时间为异常监测信号提供预警,从而提升机组安全稳定运行的可靠性。 展开更多
关键词 变分相关性权重优化informer(VCW-informer) 天然气压缩机 监测数据 异常预警 深度学习 信号分解
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基于PCA-Informer算法的设施栽培三七温湿度预测和预警系统
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作者 李娜 张舒凌 +4 位作者 张文韬 杨启良 梁嘉平 刘小刚 杜天牧 《中国农业气象》 2025年第10期1487-1502,共16页
三七具有极高的药用和经济价值,喜温喜湿,温湿度是影响其生长的重要环境参数。目前,三七设施栽培以人工经验为主,设施环境调控存在严重滞后性,导致三七易受病虫害影响造成减产,严重阻碍产业发展。本研究利用卷积神经网络(CNN)、循环神... 三七具有极高的药用和经济价值,喜温喜湿,温湿度是影响其生长的重要环境参数。目前,三七设施栽培以人工经验为主,设施环境调控存在严重滞后性,导致三七易受病虫害影响造成减产,严重阻碍产业发展。本研究利用卷积神经网络(CNN)、循环神经网络(RNN)、长短期记忆神经网络(LSTM)和Informer模型四种深度机器学习算法初步优选设施三七温湿度预测模型,构建改进的PCA-Informer模型以提高模型训练效率和性能。同时,通过环境监测传感器实现数据采集,将PCA-Informer模型嵌入平台软件,采用Django框架结合Python技术实现平台主要功能模块,开发三七设施栽培环境监测、温湿度预测和预警平台。结果表明:(1)Informer模型相较于其他三种深度机器学习算法预测精度最高,空气温度和湿度的平均绝对误差(MAE)分别为0.860℃和3.870个百分点,决定系数(R^(2))分别为0.959和0.964。(2)通过Informer模型的Encoder层加入主成分分析(PCA)算法构建的PCA-Informer模型,可提高设施栽培三七温湿度预测模型的训练效率和性能。相较于Informer模型,PCA-Informer模型预测空气温度和湿度的MAE分别减少0.140℃和0.621个百分点,R^(2)分别提高了0.0100和0.0021。(3)三七设施栽培环境监测、温湿度预测和预警平台可实现设施三七未来3d温湿度精准预测和预警。 展开更多
关键词 三七 设施栽培 深度学习 温湿度预测 PCA-informer模型 预警平台
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变速率加载砂岩力学响应及声发射破裂前兆识别预警
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作者 华心祝 李琛 +2 位作者 杨朋 刘啸 闫纪元 《煤炭科学技术》 北大核心 2026年第1期67-83,共17页
切顶留巷是深部煤炭安全高效开采的重要技术手段,但受一次掘进与二次强采动影响,围岩变形剧烈,底鼓问题突出。为揭示留巷过程中覆岩-底板的应力传递规律及底板岩石在变速率加载下的破裂演化机制,开展了相似模拟及单轴变速率加载试验,综... 切顶留巷是深部煤炭安全高效开采的重要技术手段,但受一次掘进与二次强采动影响,围岩变形剧烈,底鼓问题突出。为揭示留巷过程中覆岩-底板的应力传递规律及底板岩石在变速率加载下的破裂演化机制,开展了相似模拟及单轴变速率加载试验,综合分析底板应力响应特征与不同加载速率下岩石力学、声发射与分形行为。相似模拟结果表明:巷道开挖后底板表面瞬时卸荷,随工作面推进与覆岩周期垮落,垮落矸石堆积压实使得底板应力回升;覆岩结构稳定后底板应力变化趋缓,系统进入准静态平衡阶段。在此基础上开展的变速率加载岩石力学试验表明,加载速率显著影响砂岩的破裂模式与力学响应,快速加载下应变速率高、裂纹集中起裂并迅速贯通,能量释放剧烈,表现为典型脆性破坏;较早切入准静态加载时,裂纹呈多点萌生与缓慢贯通特征,峰前非线性阶段延长,脆性减弱、延性增强;全程准静态加载下损伤累积最充分,破裂过程呈渐进性。声发射结果显示,快速加载下AE信号突发集中、计数与能量峰前急剧上升,预警窗口极短;降低加载速率后,裂纹扩展受抑、事件转为连续活跃,峰后仍保持高能量释放。多重分形分析表明,AE分形谱呈“钟形”分布,随应力增加先展宽后收敛。快速加载或晚期切速使谱形左偏、突发性增强;低速或早期切速下谱形更对称,表明裂纹渐进扩展。基于AE多参量方差构建的预警指标进一步表明快速加载下方差在峰前短时急剧抬升,预警信号出现晚、持续时间短;降低加载速率后,方差呈持续上升、多峰密集,L1、L2、L3三级预警依次触发,窗口明显延长;全程准静态加载时方差波动更密集,可提前识别裂纹加速贯通的过程,表明加载速率越低,裂隙演化越充分,破裂前兆越易识别。降低加载速率有利于裂纹的充分演化发展,从而增强岩石破裂前兆特征的可识别性与可预见性,为深部岩体稳定性监测与灾害预警提供理论依据。 展开更多
关键词 切顶留巷 底板应力 多重分形 前兆信息 声发射预警
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巨厚顶板砂岩含水层下采煤水害防治:理论与技术
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作者 李振华 黄玉峰 +5 位作者 王文强 杜锋 丁湘 马丹 张勃阳 翟明磊 《煤炭科学技术》 北大核心 2026年第1期270-289,共20页
黄陇煤田煤层赋存于洛河组巨厚砂岩含水层之下,该含水层地下水储量丰富、补给充分,造成煤层开采受顶板水害威胁严重,顶板水害防治技术成为制约矿井安全生产的关键。为全方位分析黄陇煤田巨厚顶板砂岩含水层下采煤水害防治现状,探讨未来... 黄陇煤田煤层赋存于洛河组巨厚砂岩含水层之下,该含水层地下水储量丰富、补给充分,造成煤层开采受顶板水害威胁严重,顶板水害防治技术成为制约矿井安全生产的关键。为全方位分析黄陇煤田巨厚顶板砂岩含水层下采煤水害防治现状,探讨未来基于新技术开展顶板水害防控的重点攻关方向,从水害防治理论和技术视角全方位总结了近年来黄陇煤田巨厚复合顶板砂岩含水层水害防治的研究进展,依据黄陇煤田煤层开采过程中顶板水害特点,顶板充水类型总体上可以划分为3类6型,其中持续性高涌水量水害和非持续性涌水类中的脉冲式涌水、离层突水灾害为主要灾害形式;在理论方面,通过总结巨厚顶板砂岩含水层突水灾害形成的水源、通道、突水预兆、顶板结构、含水层的补给-径流-排泄条件、顶板覆岩破断以及导水通道演化等研究现状,明确了在高强度采动影响下,导水裂隙带发育高度显著,裂采比最高达30以上,直接沟通含水层是引发持续性涌水的原因,含水层补给和采动挤压的双重作用是造成覆岩弯曲下沉带与裂隙带交接区域产生离层空间形成脉冲式突水灾害的原因;总体上明确了强采动条件下覆岩变形破坏特征及水害成灾机制;在技术方面,通过分析现有的导水裂隙带发育高度探查、含水层水文地质参数获取、巨厚顶板砂岩含水层水害治理等技术的优缺点,提出“地下水截流”结合长距离定向钻探与靶向探放技术,形成的“断源截流、集中疏排”是有效防治巨厚顶板砂岩含水层突水的技术体系,并且明确了该技术体系的多元信息智能监测与预警技术建设方向。在总结现行巨厚顶板砂岩含水层水害防治理论和技术的基础上,结合前沿发展方向,明确了黄陇煤田当前仍面临强采动条件下离层水复杂流动路径释水致灾机理不明等问题,在深层次突水机理、高精度探测与监测、新型注浆材料研发、保水开采与生态保护以及矿井水资源化与智能化防控方面指出了今后需要重点发展的方向。 展开更多
关键词 巨厚顶板砂岩含水层 深埋侏罗系煤层 顶板水害防治 离层突水 多元信息预警
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Weak characteristic information extraction from early fault of wind turbine generator gearboxKeywords wind turbine generator gearbox, B-singular value decomposition, local mean decomposition, weak characteristic information extraction, early fault warning 被引量:2
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作者 Xiaoli XU Xiuli LIU 《Frontiers of Mechanical Engineering》 SCIE CSCD 2017年第3期357-366,共10页
Given the weak early degradation characteristic information during early fault evolution in gearbox of wind turbine generator, traditional singular value decomposition (SVD)-based denoising may result in loss of use... Given the weak early degradation characteristic information during early fault evolution in gearbox of wind turbine generator, traditional singular value decomposition (SVD)-based denoising may result in loss of useful information. A weak characteristic information extraction based on μ-SVD and local mean decomposition (LMD) is developed to address this problem. The basic principle of the method is as follows: Determine the denoising order based on cumulative contribution rate, perform signal reconstruction, extract and subject the noisy part of signal to LMD and μ-SVD denoising, and obtain denoised signal through superposition. Experimental results show that this method can significantly weaken signal noise, effectively extract the weak characteristic information of early fault, and facilitate the early fault warning and dynamic predictive maintenance. 展开更多
关键词 wind turbine generator gearbox μ-singular value decomposition local mean decomposition weak characteristic information extraction early fault warning
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Early Warning and Monitoring of Coronavirus Disease 2019 Using Baidu Search Index and Baidu Information Index in Guangxi,China
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作者 Yihong Xie Wanwan Zhou +3 位作者 Jinhui Zhu Yuhua Ruan Xiaomin Wang Tengda Huang 《Infectious Microbes & Diseases》 2022年第4期168-174,共7页
Coronavirus disease 2019(COVID-19)is an emerging infectious disease,and it is important to detect early and monitor the disease trend for policymakers to make informed decisions.We explored the predictive utility of B... Coronavirus disease 2019(COVID-19)is an emerging infectious disease,and it is important to detect early and monitor the disease trend for policymakers to make informed decisions.We explored the predictive utility of Baidu Search Index and Baidu Information Index for early warning of COVID-19 and identified search keywords for further monitoring of epidemic trends in Guangxi.A time-series analysis and Spearman correlation between the daily number of cases and both the Baidu Search Index and Baidu Information Index were performed for seven keywords related to COVID-19 from January 8 to March 9,2020.The time series showed that the temporal distributions of the search terms“coronavirus,”“pneumonia”and“mask”in the Baidu Search Index were consistent and had 2 to 3 days'lead time to the reported cases;the correlation coefficients were higher than 0.81.The Baidu Search Index volume in 14 prefectures of Guangxi was closely related with the number of reported cases;it was not associated with the local GDP.The Baidu Information Index search terms“coronavirus”and“pneumonia”were used as frequently as 192,405.0 and 110,488.6 per million population,respectively,and they were also significantly associated with the number of reported cases(rs>0.6),but they fluctuated more than for the Baidu Search Index and had 0 to 14 days'lag time to the reported cases.The Baidu Search Index with search terms“coronavirus,”“pneumonia”and“mask”can be used for early warning and monitoring of the epidemic trend of COVID-19 in Guangxi,with 2 to 3 days'lead time. 展开更多
关键词 COVID-19 Baidu Search Index Baidu information Index early warning monitoring epidemic trend
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地震预警信息服务的时效性分析与探讨 被引量:1
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作者 蒋宏毅 李丽 +3 位作者 丁晶 包文超 翟颖 马秀丹 《中国地震》 北大核心 2025年第2期354-360,共7页
破坏性地震发生后,高效的地震预警服务对于降低人员伤亡、减少地震造成的损失至关重要。预警服务的时效性,定义为从地震发生时刻至地震警报(一般指地震预警系统发出的第一报)发出的时间差。时效性是地震预警系统工程的重要评估指标,其... 破坏性地震发生后,高效的地震预警服务对于降低人员伤亡、减少地震造成的损失至关重要。预警服务的时效性,定义为从地震发生时刻至地震警报(一般指地震预警系统发出的第一报)发出的时间差。时效性是地震预警系统工程的重要评估指标,其关系到地震预警的盲区大小和为地震预警区提供的避险逃生时间,即预警时间的长短。因此,缩小地震警报的用时,优化和控制时延是地震预警系统最重要的技术。本文探讨了地震预警的原理及其工程架构,重点分析影响预警时效性的关键因素,并据此提出控制预警时效性的策略和关键保障方法。 展开更多
关键词 时效性 地震预警信息服务 预警时间 地震预警终端
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基于最大信息系数法的卧沙溪滑坡变形相关性分析及预警模型研究 被引量:2
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作者 尚敏 王殿鹏 +2 位作者 易庆林 袁朔 宋云鹏 《工程地质学报》 北大核心 2025年第2期572-580,共9页
本篇以三峡库区卧沙溪滑坡为研究对象,运用最大信息量法对滑坡变形影响因素相关性进行了定量分析。结果表明降雨是坡体加速变形的主要诱因,库水位变化仅起到加速滑坡变形的作用,而非既有研究认为的动水压力型滑坡。为提升滑坡预警和预... 本篇以三峡库区卧沙溪滑坡为研究对象,运用最大信息量法对滑坡变形影响因素相关性进行了定量分析。结果表明降雨是坡体加速变形的主要诱因,库水位变化仅起到加速滑坡变形的作用,而非既有研究认为的动水压力型滑坡。为提升滑坡预警和预测的准确度,采用了最大信息系数法(MIC)与改进的切线角法,对近8年来滑坡次级滑体发生的4次阶跃变形进行了分析,确定了引发这些阶跃变形的降雨阈值和位移速率阈值。基于这些阈值,建立了一个更加完善的新型预警模型。研究结果不仅有助于提升对卧沙溪滑坡的监测水平,也为类似地质灾害的监测预警提供了有价值的参考。 展开更多
关键词 卧沙溪滑坡 定量分析 最大信息系数 预警模型
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基于LDA-fsQFD的农产品供应链风险预警信息识别 被引量:2
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作者 高齐圣 袁震 欧阳道中 《情报杂志》 北大核心 2025年第5期156-164,共9页
[研究目的]利用社交媒体和大数据可实现农产品质量安全治理由事后监管转变为事前预防,为农产品供应链风险管理提供依据。[研究方法]本研究将主题模型、模糊集和质量功能展开方法融合为LDA-fsQFD模型。该模型从社交媒体评论数据识别消费... [研究目的]利用社交媒体和大数据可实现农产品质量安全治理由事后监管转变为事前预防,为农产品供应链风险管理提供依据。[研究方法]本研究将主题模型、模糊集和质量功能展开方法融合为LDA-fsQFD模型。该模型从社交媒体评论数据识别消费者需求特性和供应链可能风险点,采用模糊集进行质量屋各部分计算与分析,最终计算出农产品供应链中预警信息的优先级,据此确定关键控制点并实施风险预警。[研究结果/结论]实例结果表明,基于LDA-fsQFD模型方法,有效识别公众对农产品的绿色消费需求和期望,进而转化为供应链中的关键风险预警信息。此外,可正确树立公众绿色消费理念,规范农户和企业绿色生产行为,不断提升农产品质量安全水平。 展开更多
关键词 农产品供应链 质量安全风险 预警信息 大数据 LDA-fsQFD
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矿井外因火灾监测预警与智能防控技术
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作者 梁运涛 王伟 《矿业安全与环保》 北大核心 2025年第2期1-8,共8页
矿井外因火灾防治存在监测手段单一、预警准确率低、应急辅助决策缺失、无法实现火灾就地处置的难题,智能化水平亟待提高。为探究外因火灾精准预警与智能联动控制一体化解决方案,从信息感知、数据集成、智能预警、辅助决策和联动控制5... 矿井外因火灾防治存在监测手段单一、预警准确率低、应急辅助决策缺失、无法实现火灾就地处置的难题,智能化水平亟待提高。为探究外因火灾精准预警与智能联动控制一体化解决方案,从信息感知、数据集成、智能预警、辅助决策和联动控制5个方面综述了矿井外因火灾监测预警与智能防控研究进展,具体包括:在信息感知方面,采用先进监测手段、开发高精度检测装备和优选外因火灾精准预警指标,实现火灾信息全程动态感知;在数据集成方面,建议统一数据采集、传输、存储和访问接口标准,规范各类数据的接入;在智能预警方面,提出智能预警关键参数识别方法和预警策略;在辅助决策方面,提出包含时空信息处理、时空图谱构建、时空分析与智能决策的一站式解决方案;在联动控制方面,建立包含广播系统、安全逃生系统、通风控制系统和灭火系统的智能联动控制系统。 展开更多
关键词 外因火灾 信息感知 数据集成 智能预警 辅助决策 联动控制
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寒区高铁隧道口边坡冻融失稳智能监测预警方法
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作者 李博 梁媛 +1 位作者 马云东 于露 《吉林大学学报(工学版)》 北大核心 2025年第9期2985-2997,共13页
针对寒区高铁隧道口边坡冻融失稳风险及监测数据孤立问题,本文提出融合北斗定位、毫米波雷达、InSAR等多源信息的“感知-传输-分析-预警”智能监测系统。该系统通过构建结构变形、环境扰动与异常响应3类指标,采用“点-线-面-体”部署策... 针对寒区高铁隧道口边坡冻融失稳风险及监测数据孤立问题,本文提出融合北斗定位、毫米波雷达、InSAR等多源信息的“感知-传输-分析-预警”智能监测系统。该系统通过构建结构变形、环境扰动与异常响应3类指标,采用“点-线-面-体”部署策略,实现边坡状态的多维感知;同时,研发位移触发+图像复核+多源融合的预警模型,并开发数字化平台,实现风险分级响应。工程验证结果表明,该系统在冻融期具有高适应性,可有效识别滑坡前兆。 展开更多
关键词 道路工程 寒区边坡 冻融循环 多源信息融合 智能监测预警
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