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Redox mechanism of geobattery and related electrical signals using a novel real-time self-potential monitoring experimental platform 被引量:1
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作者 XIE Jing CUI Yi-an +4 位作者 ZHANG Li-juan GUO You-jun CHEN Hang ZHANG Peng-fei LIU Jian-xin 《Journal of Central South University》 CSCD 2024年第11期4155-4173,共19页
Controlled laboratory experiments are proved to be a valuable tool for investigating changes in underground physical properties and the related response of surface geophysical signals.The self-potential(SP)method is w... Controlled laboratory experiments are proved to be a valuable tool for investigating changes in underground physical properties and the related response of surface geophysical signals.The self-potential(SP)method is widely used in mineral resource exploration due to its direct correlation with underground electrochemical gradients.This paper presented the design and construction of an experimental platform based on a multi-channel SP monitoring system.The proposed platform was used to monitor the anodizing corrosion process of different metal blocks from a laboratory perspective,record the real-time SP signal generated by the redox reaction,as well as investigate the geobattery mechanism associated with the natural polarization process of metal mineral resources.The experimental results demonstrate that the constructed SP monitoring platform effectively captures time-series SP signals and provides direct laboratory evidence for the geobattery model.The measured SP data were quantitatively interpreted using the simulated annealing algorithm,and the inversion results closely match the real model.This finding highlights the potential of the SP method as a promising tool for determining the location and spatial distribution of underground polarizers.The study holds reference value for the exploration and exploitation of mineral resources in both terrestrial and marine environments. 展开更多
关键词 SELF-POTENTIAL real-time monitoring laboratory experiment geobattery mechanism quantitative inversion
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Real-Time Monitoring Method for Cow Rumination Behavior Based on Edge Computing and Improved MobileNet v3
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作者 ZHANG Yu LI Xiangting +4 位作者 SUN Yalin XUE Aidi ZHANG Yi JIANG Hailong SHEN Weizheng 《智慧农业(中英文)》 CSCD 2024年第4期29-41,共13页
[Objective]Real-time monitoring of cow ruminant behavior is of paramount importance for promptly obtaining relevant information about cow health and predicting cow diseases.Currently,various strategies have been propo... [Objective]Real-time monitoring of cow ruminant behavior is of paramount importance for promptly obtaining relevant information about cow health and predicting cow diseases.Currently,various strategies have been proposed for monitoring cow ruminant behavior,including video surveillance,sound recognition,and sensor monitoring methods.How‐ever,the application of edge device gives rise to the issue of inadequate real-time performance.To reduce the volume of data transmission and cloud computing workload while achieving real-time monitoring of dairy cow rumination behavior,a real-time monitoring method was proposed for cow ruminant behavior based on edge computing.[Methods]Autono‐mously designed edge devices were utilized to collect and process six-axis acceleration signals from cows in real-time.Based on these six-axis data,two distinct strategies,federated edge intelligence and split edge intelligence,were investigat‐ed for the real-time recognition of cow ruminant behavior.Focused on the real-time recognition method for cow ruminant behavior leveraging federated edge intelligence,the CA-MobileNet v3 network was proposed by enhancing the MobileNet v3 network with a collaborative attention mechanism.Additionally,a federated edge intelligence model was designed uti‐lizing the CA-MobileNet v3 network and the FedAvg federated aggregation algorithm.In the study on split edge intelli‐gence,a split edge intelligence model named MobileNet-LSTM was designed by integrating the MobileNet v3 network with a fusion collaborative attention mechanism and the Bi-LSTM network.[Results and Discussions]Through compara‐tive experiments with MobileNet v3 and MobileNet-LSTM,the federated edge intelligence model based on CA-Mo‐bileNet v3 achieved an average Precision rate,Recall rate,F1-Score,Specificity,and Accuracy of 97.1%,97.9%,97.5%,98.3%,and 98.2%,respectively,yielding the best recognition performance.[Conclusions]It is provided a real-time and effective method for monitoring cow ruminant behavior,and the proposed federated edge intelligence model can be ap‐plied in practical settings. 展开更多
关键词 cow rumination behavior real-time monitoring edge computing improved MobileNet v3 edge intelligence model Bi-LSTM
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A process monitoring method for autoregressive-dynamic inner total latent structure projection
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作者 CHEN Yalin KONG Xiangyu LUO Jiayu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1326-1336,共11页
As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decompos... As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decomposition of the input space by DiPLS,there are false alarms in the actual industrial process during fault detection.To address the above problems,a dynamic modeling method based on autoregressive-dynamic inner total PLS(AR-DiTPLS)is proposed.The method first uses the regression relation matrix to decompose the input space orthogonally,which reduces useless information for the predic-tion output in the quality-related dynamic subspace.Then,a vector autoregressive model(VAR)is constructed for the predic-tion score to separate dynamic information and static informa-tion.Based on the VAR model,appropriate statistical indicators are further constructed for online monitoring,which reduces the occurrence of false alarms.The effectiveness of the method is verified by a Tennessee-Eastman industrial simulation process and a three-phase flow system. 展开更多
关键词 dynamic characteristic fault detection feature extraction process monitoring projection to latent structure(PLS) quality-related spatial partitioning
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A Class of Parallel Algorithms of Real-TimeNumerical Simulation for Stiff Dynamic System 被引量:2
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作者 Cao Xuenian Liu Degui Li Shoufu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第4期51-58,共8页
In this paper a class of real-time parallel modified Rosenbrock methods of numerical simulation is constructed for stiff dynamic systems on a multiprocessor system, and convergence and numerical stability of these met... In this paper a class of real-time parallel modified Rosenbrock methods of numerical simulation is constructed for stiff dynamic systems on a multiprocessor system, and convergence and numerical stability of these methods are discussed. A-stable real-time parallel formula of two-stage third-order and A(α)-stable real-time parallel formula with o ≈ 89.96° of three-stage fourth-order are particularly given. The numerical simulation experiments in parallel environment show that the class of algorithms is efficient and applicable, with greater speedup. 展开更多
关键词 dynamic system real-time simulation Parallel algorithms?
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Current Working Situation and Countermeasures of Dynamic Monitoring of Geothermal Resource Exploitation and Utilization in Tianjin
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作者 Guanghui Tian,Meixiang Zeng,Wanqing Cheng,Jun Li,Sumin Zhao Tianjin Geothermal Exploration and Development Designing Institute,Tianjin 300250,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期283-283,共1页
Dynamic monitoring is an important basic work in the sustainable exploitation and utilization of geothermal resources.It offers basic data for geothermal management department to make out the plan of geothermal resour... Dynamic monitoring is an important basic work in the sustainable exploitation and utilization of geothermal resources.It offers basic data for geothermal management department to make out the plan of geothermal resources by collecting and analyzing the outdoor dynamic monitoring data. Tianjin is one of the earliest cities in exploiting and utilizing geothermal resources,and the 展开更多
关键词 GEOTHERMAL RESOURCES dynamic monitoring sustainable COUNTERMEASURE
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A Real-time Monitoring System for Tire Blowout or Severe Leakage
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作者 陈庆樟 郭立书 杨雄 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第2期126-128,共3页
The tire blowout or severe leakage real-time monitoring is one of key technologies for developing a tire blowout automatic braking system.An indirect real-time monitoring method to fuse analyses of tire vibration and ... The tire blowout or severe leakage real-time monitoring is one of key technologies for developing a tire blowout automatic braking system.An indirect real-time monitoring method to fuse analyses of tire vibration and effective radius is provided in this paper,and a monitoring system is developed.The calibration and related test results showthat the system can detect the tire blowout in low and middle vehicle speeds and the severe leakage in all speeds timely and accurately. 展开更多
关键词 AUTOMOBILE tire blowout LEAKAGE real-time monitoring
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Mechanism,prevention,and control of mining-induced dynamic disasters in underground metal mines in China:Challenges and solutions
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作者 LI Peng CAI Mei-feng +3 位作者 MIAO Sheng-jun REN Fen-hua GORJIAN Mostafa PENG Chao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2549-2606,共58页
Metal mineral resources play an indispensable role in the development of the national economy.Dynamic disasters in underground metal mines seriously threaten mining safety,which are major scientific and technological ... Metal mineral resources play an indispensable role in the development of the national economy.Dynamic disasters in underground metal mines seriously threaten mining safety,which are major scientific and technological problems to be solved urgently.In this article,the occurrence status and grand challenges of some typical dynamic disasters involving roof falling,spalling,collapse,large deformation,rockburst,surface subsidence,and water inrush in metal mines in China are systematically presented,the characteristics of mining-induced dynamic disasters are analyzed,the examples of dynamic disasters occurring in some metal mines in China are summarized,the occurrence mechanism,monitoring and early warning methods,and prevention and control techniques of these disasters are highlighted,and some new opinions,suggestions,and solutions are proposed simultaneously.Moreover,some shortcomings in current disaster research are pointed out,and the direction of efforts to improve the prevention and control level of dynamic disasters in China’s metal mines in the future is prospected.The integration of forward-looking key innovative theories and technologies in the abovementioned aspects will greatly enhance the cognitive level of disaster prevention and mitigation in China’s metal mining industry and achieve a significant shift from passive disaster relief to active disaster prevention. 展开更多
关键词 underground metal mines dynamic disasters MECHANISM monitoring and early warning prevention and control
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Improving autoencoder-based unsupervised damage detection in uncontrolled structural health monitoring under noisy conditions
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作者 Yang Kang Wang Linyuan +4 位作者 Gao Chao Chen Mozhi Tian Zhihui Zhou Dunzhi Liu Yang 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第6期91-100,共10页
Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enh... Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enhance the performance of guided wave damage detection in noisy environments is crucial.This paper introduces a local temporal principal component analysis(PCA)reconstruction approach for denoising guided waves prior to implementing unsupervised damage detection,achieved through novel autoencoder-based reconstruction.Experimental results demonstrate that the proposed denoising method significantly enhances damage detection performance when guided waves are contaminated by noise,with SNR values ranging from 10 to-5 dB.Following the implementation of the proposed denoising approach,the AUC score can elevate from 0.65 to 0.96 when dealing with guided waves corrputed by noise at a level of-5 dB.Additionally,the paper provides guidance on selecting the appropriate number of components used in the denoising PCA reconstruction,aiding in the optimization of the damage detection in noisy conditions. 展开更多
关键词 structural health monitoring guided waves principal component analysis deep learning DENOISING dynamic environmental condition
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A Class of Fast Algorithms in Real-Time Simulation 被引量:4
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作者 Zhu Zhenmin & Liu Degui(Beijing Institute of Computer Application and Simulation Technology, 100854, P. R. China)Li Shoufu(Mathematics Department of Xiangtan University, 411105, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第4期10-20,共11页
A class of hybrid algorithms of real-time simulation based on evaluation of non-integerstep right-hand side function are presented in this paper. And some results of the convergence and stability of the algorithms are... A class of hybrid algorithms of real-time simulation based on evaluation of non-integerstep right-hand side function are presented in this paper. And some results of the convergence and stability of the algorithms are given. Using the class of algorithms, evaluation for the right-hand side function is needed once in every integration-step. Moreover, comparing with the other methods with the same amount of work, their numerical stability regions are larger and the method errors are smaller, and the numerical experiments show that the algorithms are very effective. 展开更多
关键词 real-time simulation algorithm Numerical stability CONVERGENCE dynamic system
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Fatigue damage reliability analysis for Nanjing Yangtze river bridge using structural health monitoring data 被引量:2
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作者 何旭辉 陈政清 +1 位作者 余志武 黄方林 《Journal of Central South University of Technology》 EI 2006年第2期200-203,共4页
To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural ... To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural fatigue damage reliability were derived. Fatigue damage reliability analysis of some critical members of the Nanjing Yangtze river bridge was carried out by using the strain-time histories measured by the structural health monitoring system of the bridge. The corresponding stress spectra were obtained by the real-time rain-flow counting method. Results of fatigue damage were calculated respectively by the reliability method at different reliability and compared with Miner’s rule. The results show that the fatigue damage of critical members of the Nanjing Yangtze river bridge is very small due to its low live-load stress level. 展开更多
关键词 fatigue damage reliability evaluation railway steel bridge structural health monitoring real-time rainflow counting method
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A combined finite element and deep learning network for structural dynamic response estimation on concrete gravity dam subjected to blast loads 被引量:1
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作者 Xin Fang Heng Li +3 位作者 She-rong Zhang Xiao-hua Wang Chao Wang Xiao-chun Luo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期298-313,共16页
Social infrastructures such as dams are likely to be exposed to high risk of terrorist and military attacks,leading to increasing attentions on their vulnerability and catastrophic consequences under such events.This ... Social infrastructures such as dams are likely to be exposed to high risk of terrorist and military attacks,leading to increasing attentions on their vulnerability and catastrophic consequences under such events.This paper tries to develop advanced deep learning approaches for structural dynamic response prediction and dam health diagnosis.At first,the improved long short-term memory(LSTM)networks are proposed for data-driven structural dynamic response analysis with the data generated by a single degree of freedom(SDOF)and the finite numerical simulation,due to the unavailability of abundant practical structural response data of concrete gravity dam under blast events.Three kinds of LSTM-based models are discussed with the various cases of noise-contaminated signals,and the results prove that LSTM-based models have the potential for quick structural response estimation under blast loads.Furthermore,the damage indicators(i.e.,peak vibration velocity and domain frequency)are extracted from the predicted velocity histories,and their relationship with the dam damage status from the numerical simulation is established.This study provides a deep-learning based structural health monitoring(SHM)framework for quick assessment of dam experienced underwater explosions through blastinduced monitoring data. 展开更多
关键词 Deep learning Structural health monitoring dynamic response Concrete gravity dam
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Scheduling transactions in mobile distributed real-time database systems 被引量:1
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作者 雷向东 赵跃龙 +1 位作者 陈松乔 袁晓莉 《Journal of Central South University of Technology》 EI 2008年第4期545-551,共7页
A DMVOCC-MVDA (distributed multiversion optimistic concurrency control with multiversion dynamic adjustment) protocol was presented to process mobile distributed real-time transaction in mobile broadcast environment... A DMVOCC-MVDA (distributed multiversion optimistic concurrency control with multiversion dynamic adjustment) protocol was presented to process mobile distributed real-time transaction in mobile broadcast environments. At the mobile hosts, all transactions perform local pre-validation. The local pre-validation process is carried out against the committed transactions at the server in the last broadcast cycle. Transactions that survive in local pre-validation must be submitted to the server for local final validation. The new protocol eliminates conflicts between mobile read-only and mobile update transactions, and resolves data conflicts flexibly by using multiversion dynamic adjustment of serialization order to avoid unnecessary restarts of transactions. Mobile read-only transactions can be committed with no-blocking, and respond time of mobile read-only transactions is greatly shortened. The tolerance of mobile transactions of disconnections from the broadcast channel is increased. In global validation mobile distributed transactions have to do check to ensure distributed serializability in all participants. The simulation results show that the new concurrency control protocol proposed offers better performance than other protocols in terms of miss rate, restart rate, commit rate. Under high work load (think time is ls) the miss rate of DMVOCC-MVDA is only 14.6%, is significantly lower than that of other protocols. The restart rate of DMVOCC-MVDA is only 32.3%, showing that DMVOCC-MVDA can effectively reduce the restart rate of mobile transactions. And the commit rate of DMVOCC-MVDA is up to 61.2%, which is obviously higher than that of other protocols. 展开更多
关键词 mobile distributed real-time database systems muliversion optimistic concurrency control multiversion dynamic adjustment pre-validation multiversion data broadcast
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Health condition monitoring with multiple physical signals in tensile test for double-material friction welding
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作者 张玉波 徐滨士 +2 位作者 王海斗 杨大祥 朱丽娜 《Journal of Central South University》 SCIE EI CAS 2012年第10期2705-2711,共7页
The manifold physical signals including micro resistance,infrared thermal signal and acoustic emission signal in the tensile test for double-material friction welding normative samples were monitored and collected dyn... The manifold physical signals including micro resistance,infrared thermal signal and acoustic emission signal in the tensile test for double-material friction welding normative samples were monitored and collected dynamically by TH2512 micro resistance measuring apparatus,flir infrared thermal camera and acoustic emission equipment which possesses 18 bit PCI-2 data acquisition board.Applied acoustic emission and thermal infrared NDT(non-destructive testing) means were used to verify the feasibility of using resistance method and to monitor dynamic damage of the samples.The research of the dynamic monitoring system was carried out with multi-information fusion including resistance,infrared and acoustic emission.The results show that the resistance signal,infrared signal and acoustic emission signal collected synchronously in the injury process of samples have a good mapping.Electrical,thermal and acoustic signals can more accurately capture initiation and development of micro-defects in the sample.Using dynamic micro-resistance method to monitor damage is possible.The method of multi-information fusion monitoring damage possesses higher reliability,which makes the establishing of health condition diagnosing and early warning platform with multiple physical information monitoring possible. 展开更多
关键词 micro resistance pictorial infrared photography acoustic emission nondestructive testing dynamic monitoring
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Mathematical model research on landslide monitoring through GPS
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作者 刘文伟 宋迎春 +1 位作者 朱建军 汤井田 《Journal of Central South University of Technology》 EI 2006年第4期456-460,共5页
Assuming that road slope and landslide object are rigid, the landslide’s moving displacement was drawn based on their geometry shapes and the physi-mechanical features of materials, and the dynamic model of landslide... Assuming that road slope and landslide object are rigid, the landslide’s moving displacement was drawn based on their geometry shapes and the physi-mechanical features of materials, and the dynamic model of landslide was also set up, then DDOD(double difference observation data) was combined with the deformed monitoring point and the carrier phase observation data on base point, which can be used to monitor the landslide’s deformation rule from horizontal, vertical and directional view simultaneously. Observing equation was set up, which sufficiently reflects the activities of landslide in entire directions. Filter model includes some information such as mechanical state and GPS observing data by Kalman filter. 展开更多
关键词 dynamic landslide landslide monitoring Kalman filter
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地球物理技术向油藏开发延伸的现状与展望 被引量:1
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作者 黄旭日 《石油物探》 北大核心 2025年第1期15-31,共17页
地球物理技术近几十年来一直不断地向油气藏开发延伸,在面向目标成像、岩石物理、多约束反演、地震约束和驱动建模、油藏动态监测与表征以及多数据融合与智能化等多方面取得了长足的进步。地球物理技术向油藏开发延伸是地球物理技术本... 地球物理技术近几十年来一直不断地向油气藏开发延伸,在面向目标成像、岩石物理、多约束反演、地震约束和驱动建模、油藏动态监测与表征以及多数据融合与智能化等多方面取得了长足的进步。地球物理技术向油藏开发延伸是地球物理技术本身发展的需要,也是更好开发油气藏的需要。与勘探地球物理相比,面向油藏开发领域的地球物理技术,由于数据条件、关键技术问题与目标的变化而形成了具有自身独特特征的技术体系。旨在简单总结和梳理该领域的发展和现状,目的是能和读者分享作者对未来技术发展的思考,希望对读者有所启发。 展开更多
关键词 油藏开发 油藏地球物理 动态监测 动态表征 油藏模型 多约束地震反演 多数据融合
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基于电能质量监测数据的电压暂降敏感负荷识别 被引量:1
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作者 张逸 张良羽 +2 位作者 陈锦涛 姚文旭 陈敏 《电力自动化设备》 北大核心 2025年第2期176-184,共9页
为了解决现有方法无法适用于已投运负荷或需要已知敏感负荷类型等问题,提出一种基于电能质量监测数据的敏感负荷识别方法,以有功功率有效值监测数据为切入点,采用Hodrick-Prescott滤波、滑动均值分段进行电压暂降事件时段划分;利用电压... 为了解决现有方法无法适用于已投运负荷或需要已知敏感负荷类型等问题,提出一种基于电能质量监测数据的敏感负荷识别方法,以有功功率有效值监测数据为切入点,采用Hodrick-Prescott滤波、滑动均值分段进行电压暂降事件时段划分;利用电压暂降事件前、后的电能质量监测数据变化量构建待处理稳态数据集,通过动态聚类来有效划分各次电压暂降事件;对各暂降事件集进行边界拟合,得到多个拟合拐点,并与预设拐点行比较,完成对用户所含敏感负荷的类型识别。通过MATLAB/Simulink仿真算例和实际敏感用户电能质量监测数据对所提方法进行验证,结果表明所提方法可准确识别交流接触器、变频调速系统、可编程逻辑控制器、个人计算机这4种典型敏感负荷,能有效利用稳态电能质量监测数据与电压暂降事件数据进行综合分析,具有成本低、可实施性强的优点。 展开更多
关键词 敏感负荷识别 电能质量监测数据 电压暂降 动态K-means聚类 VTC拐点拟合
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基于船载雷达系统的综合保障技术研究
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作者 房新兵 毛南平 +1 位作者 苏䶮 孙晓东 《现代雷达》 北大核心 2025年第1期79-85,共7页
当前船载雷达系统保障模式通常采用定期巡检或主动报修等被动式保障,造成故障信息反馈不及时,影响系统效能发挥。在系统设计中引入健康管理技术,可有效避免或降低系统任务故障发生,提升系统的堪用度。文中从雷达健康管理架构出发,深入... 当前船载雷达系统保障模式通常采用定期巡检或主动报修等被动式保障,造成故障信息反馈不及时,影响系统效能发挥。在系统设计中引入健康管理技术,可有效避免或降低系统任务故障发生,提升系统的堪用度。文中从雷达健康管理架构出发,深入开展基于故障影响及危害性的健康评估,根据其故障影响及任务可靠性设计模型,评估设备的状态健康值。从系统性能(威力、精度)和分系统性能(天线阵面、伺服传动、冷却)等维度综合评价雷达健康情况,对雷达健康退化过程信息动态监测,对雷达开展状态维修提供技术手段,为促进船载雷达系统发挥工作效能、系统可靠性持续提升奠定了基础。 展开更多
关键词 船载雷达 健康值 动态监测 性能评估
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动态监测循环肿瘤细胞在肝癌患者术后随访中的作用
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作者 周鑫 张涵 徐静 《医学研究与战创伤救治》 北大核心 2025年第3期273-277,共5页
目的评估动态监测循环肿瘤细胞(CTC)在肝癌患者术后随访中的预后价值。方法选取2019年1月至2020年11月在江苏省人民医院肿瘤科就诊的确诊为肝癌并接受根治性手术治疗的24例患者的临床资料。对所有患者术前及术后根据患者真实世界实际情... 目的评估动态监测循环肿瘤细胞(CTC)在肝癌患者术后随访中的预后价值。方法选取2019年1月至2020年11月在江苏省人民医院肿瘤科就诊的确诊为肝癌并接受根治性手术治疗的24例患者的临床资料。对所有患者术前及术后根据患者真实世界实际情况进行CTC检测。将CTC相关指标归纳为:CTC检测次数、是否检测到CTM、检测到CTM次数、第一次CTC数目、最高CTC数目、有无CTC连续两次检测倍增、有无CTC连续三次检测递减,以及有无CTC连续两次检测减半事件。利用Kaplan-Meier法及单因素、多因素COX比例风险回归模型评估CTC相关指标及其他变量对无复发生存期(RFS)和总生存期(OS)的影响。结果Kaplan-Meier曲线分析显示,术前AFP水平、不同TNM分期以及随访期间连续两次CTC检测出现倍增事件可显著影响肝癌患者的临床预后(P<0.05)。单因素分析显示,AFP、CTC连续两次检测倍增是肝癌患者无复发生存期的影响因素(P<0.05),AFP、TNM分期是肝癌患者总体生存期的影响因素(P<0.05)。多因素分析显示AFP是无复发生存期、总体生存期的独立预测因素(P=0.007、0.012)。结论CTC动态监测可以作为肝癌术后复发风险预测的有力工具,有助于个体化治疗方案的制定。 展开更多
关键词 循环肿瘤细胞 肝癌 动态监测 预后
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基于深度学习运动放大的风力机结构动力特性识别
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作者 李万润 赵文海 +1 位作者 李清 杜永峰 《振动与冲击》 北大核心 2025年第14期20-31,共12页
为了有效解决基于视觉监测方法中出现的监测精度不高的问题,提出了一种基于深度学习的运动放大技术结合视觉监测方法的风力机动力特性识别方法。首先,采用编码器、操控器和解码器构建运动放大深度学习网络框架,实现视频中运动信息的任... 为了有效解决基于视觉监测方法中出现的监测精度不高的问题,提出了一种基于深度学习的运动放大技术结合视觉监测方法的风力机动力特性识别方法。首先,采用编码器、操控器和解码器构建运动放大深度学习网络框架,实现视频中运动信息的任意放大倍率生成;其次,运用Lucas-Kanade光流法结合Shi-Tomasi角点检测,增强了对放大视频的视觉鲁棒监测能力;最后,采用风力机模型进行试验验证。试验结果表明,基于深度学习的运动放大技术结合视觉监测方法可以在风力机不同环境下有效识别风力机动力特性,精确度高达98%以上。通过基于深度学习的运动放大技术与视觉监测方法相结合,可以实现小振动、远距离、非接触、低成本的结构健康监测,可为风力机等大型结构状态评估提供依据。 展开更多
关键词 结构健康监测 风力机结构 运动放大 动力特性 深度学习
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改进抗噪1D-CNN的旋转车轮动平衡状态监测
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作者 周海超 关浩东 +2 位作者 王国林 张宇 赵春来 《振动.测试与诊断》 北大核心 2025年第2期309-315,412,413,共9页
针对实车旋转车轮动平衡状态难以实时监测及预判的问题,提出了一种融合注意力机制的抗噪一维卷积神经网络(noise resistant 1D convolutional neural network,简称NRCNN)的旋转车轮动平衡健康状态监测方法。首先,构建NRCNN模型,以在实... 针对实车旋转车轮动平衡状态难以实时监测及预判的问题,提出了一种融合注意力机制的抗噪一维卷积神经网络(noise resistant 1D convolutional neural network,简称NRCNN)的旋转车轮动平衡健康状态监测方法。首先,构建NRCNN模型,以在实车车轮上添加3种不同质量平衡块的方式获得3种不同速度下对应的旋转车轮动不平衡状态下的振动信息;其次,以高斯白噪声为噪声输入,对所测旋转车轮不同动平衡状态的振动信息进行处理,获得试验样本数据,并用其进行模型训练;然后,综合运用卷积运算机制和特征变换进行t分布随机邻域嵌入(t-distributed stochastic neighbor embedding,简称t-SNE)可视化显示,实现对不同动平衡状态的分类输出。结果表明,在不同信噪比的工况下,所提出的改进NRCNN模型旋转车轮的动平衡状态监测方法相比于传统一维卷积神经网络(1D convolutional neural network,简称1D-CNN)模型,展现出更高的诊断准确性,最高可达到99.95%。 展开更多
关键词 卷积神经网络 注意力机制 车轮动平衡 状态监测 高斯白噪声
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