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Research on Transmission Line Tower Tilting and Foundation State Monitoring Technology Based onMulti-Sensor Cooperative Detection and Correction
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作者 Guangxin Zhang Minghui Liu +4 位作者 Shichao Cheng Minzhen Wang Changshun Zhao Hongdan Zhao Gaiming Zhong 《Energy Engineering》 EI 2024年第1期169-185,共17页
The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the buildi... The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the building to collapse.Many small changes caused the tower’s collapse,but the early staff often could not intuitively notice the changes in the tower’s state.In the current tower online monitoring system,terminal equipment often needs to replace batteries frequently due to premature exhaustion of power.According to the need for real-time measurement of power line tower,this research designed a real-time monitoring device monitoring the transmission tower attitude tilting and foundation state based on the inertial sensor,the acceleration of 3 axis inertial sensor and angular velocity raw data to pole average filtering pre-processing,and then through the complementary filtering algorithm for comprehensive calculation of tilt angle,the system meets the demand for inclined online monitoring of power line poles and towers regarding measurement accuracy,with low cost and power consumption.The optimization multi-sensor cooperative detection and correction measured tilt angle result relative accuracy can reach 1.03%,which has specific promotion and application value since the system has the advantages of unattended and efficient calculation. 展开更多
关键词 Transmission line tower tilting MULTI-SENSOR foundation state monitoring collaborative detection
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Home Monitoring of Estrone-3-Glucuronide (E1-3G) Levels in Two Different Ovarian Stimulation Protocols: A Pilot Study
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作者 Iavor K. Vladimirov Desislava Tacheva +2 位作者 Evan Gatev Magdalena Rangelova Martin Vladimirov 《Open Journal of Obstetrics and Gynecology》 2024年第10期1640-1656,共17页
Background: Studies have shown a strong correlation between the growth of E2 in serum and estrone-3-glucuronide (E1-3G) in urine during ovarian stimulation. Thus, we developed theoretical models for using urinary E1-3... Background: Studies have shown a strong correlation between the growth of E2 in serum and estrone-3-glucuronide (E1-3G) in urine during ovarian stimulation. Thus, we developed theoretical models for using urinary E1-3G in ovarian stimulation and focused on their experimental verification and analysis. Methods: A prospective, observational pilot study was conducted involving 54 patients who underwent 54 cycles of ovarian stimulation. The goal was to establish the growth rate of urinary E1-3G during the course of stimulation and to determine the daily upper and lower limits of growth rates at which stimulation is appropriate and safe. Controlled ovarian stimulation was performed using two different stimulation protocols—an antagonist protocol in 25 cases and a progestin-primed ovarian stimulation protocol (PPOS) in 29 cases, with fixed doses of gonadotropins. From the second day of stimulation, patients self-measured their daily urine E1-3G levels at home using a portable analyzer. In parallel, a standard ultrasound follow-up protocol accompanied by a determination of E2, LH, and P levels was applied to optimally control stimulation. Results: The average daily growth rates in both groups were about 50%. The daily increase in E1-3G for the antagonist protocol ranged from 14% to 79%, while they were 28% to 79% for the PPOS protocol. Conclusion: This is the first study to analyze the dynamics of E1-3G in two different protocols and to estimate the limits of its increase during the entire course of the stimulation. The results confirm our theoretical model for the viability of using urinary E1-3G for monitoring ovarian stimulation. 展开更多
关键词 Ovarian Stimulation monitoring E1-3G Antagonist Protocol PPOS Protocol IVF ART
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On-Line Monitoring of Grinding Status Based on Rough Set Theory
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作者 洪著财 史金飞 +1 位作者 曹杰 钟秉林 《Journal of Southeast University(English Edition)》 EI CAS 2002年第1期74-79,共6页
This paper focuses on the new approach of on line monitoring of grinding burn and wheel wear based on the rough set theory. This method adopts the grinding chip flow thermal signal, and acquires identification rules ... This paper focuses on the new approach of on line monitoring of grinding burn and wheel wear based on the rough set theory. This method adopts the grinding chip flow thermal signal, and acquires identification rules by establishing sensitive characteristic parameters and constructing the knowledge system through continuum attribute discretization, attribute reduction and knowledge acquisition, and then monitors grinding burn and wheel wear in accordance with the acquired rules. The experiment results show that the new method is effective. 展开更多
关键词 rough sets GRINDING thermal radiation on line monitoring
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大规模英语口语考试评分质量保障体系建设——以CET-SET6在线评分为例
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作者 夏伟蓉 唐俊 +1 位作者 杨林 李巍 《西南交通大学学报(社会科学版)》 2024年第4期51-67,共17页
大规模外语口语考试在线评分质量体系建设是一项系统工程,也是保障评分信度和可靠性的关键环节。在全国大学英语四、六级考试(CET)在线评分流程顶层设计指导下,三维度在线评分质量保障体系将口语评分过程中样卷及培训卷挑选流程、评分... 大规模外语口语考试在线评分质量体系建设是一项系统工程,也是保障评分信度和可靠性的关键环节。在全国大学英语四、六级考试(CET)在线评分流程顶层设计指导下,三维度在线评分质量保障体系将口语评分过程中样卷及培训卷挑选流程、评分员培训流程、评分过程动态监控流程三个不同层面的子系统一环扣一环关联起来,使标准化工作机制一步一步落到实处。该体系从宏观和微观的管理视角,自上而下而又自下而上地从不同层面对评分误差进行控制,以降低评分中因评分员主观因素造成的给分差异。CET-SET6在线评分实践表明,该保障体系的实施提升了CET-SET评分信度和效度,有效保障了评分质量。该体系的建设也可为提高大规模、高风险考试在线评分信度、效度及质量管理水平提供一定的借鉴和参考。 展开更多
关键词 大规模口语考试 评分质量保障体系 CET-SET在线评分 培训体系 动态监控体系
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On-line Popularity Monitoring Method Based on Bloom Filters and Hash tables for Differentiated Traffic 被引量:4
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作者 ZHANG Guo ZHANG Jianhui +1 位作者 WANG Binqiang ZHANG Zhen 《China Communications》 SCIE CSCD 2016年第S1期72-86,共15页
Towards line speed and accurateness on-line content popularity monitoring on Content Centric Networking(CCN) routers, we propose a three-stage scheme based on Bloom filters and hash tables for differentiated traffic. ... Towards line speed and accurateness on-line content popularity monitoring on Content Centric Networking(CCN) routers, we propose a three-stage scheme based on Bloom filters and hash tables for differentiated traffic. At the first stage, we decide whether to deliver the content to the next stage depending on traffic types. The second stage consisting of Standard Bloom filters(SBF) and Counting Bloom filters(CBF) identifies the popular content. Meanwhile, a scalable sliding time window based monitoring scheme for different traffic types is proposed to implement frequent and real-time updates by the change of popularities. Hash tables according with sliding window are used to record the popularity at the third stage. Simulation results reveal that this method reaches a 40 Gbps processing speed at lower error probability with less memory, and it is more sensitive to the change of popularity. Additionally, the architecture which can be implemented in CCN router is flexible and scalable. 展开更多
关键词 CCN line speed TRAFFIC type BLOOM filters HASH tables POPULARITY monitoring
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New Monitoring Technologies for Overhead Contact Line at 400 km.h-1 被引量:2
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作者 Chul.Jin Cho Young Park 《Engineering》 SCIE EI 2016年第3期360-365,共6页
Various technologies have recently been developed for high-speed railways, in order to boost commercial speeds from 300 km.h: to 400 km.h-1. Among these technologies, this paper introduces the 400 km-h-1 class curren... Various technologies have recently been developed for high-speed railways, in order to boost commercial speeds from 300 km.h: to 400 km.h-1. Among these technologies, this paper introduces the 400 km-h-1 class current collection performance evaluation methods that have been developed and demonstrated by Korea. Specifically, this paper reports details of the video-based monitoring techniques that have been adopted to inspect the stability of overhead contact line (OCL) components at 400 km.h-1 without direct contact with any components of the power supply system. Unlike conventional OCL monitoring systems, which detect contact wire positions using either laser sensors or line cameras, the developed system measures parameters in the active state by video data. According to experimental results that were obtained at a field-test site established at a commercial line, it is claimed that the proposed mea- surement system is capable of effectively measuring OCL parameters. 展开更多
关键词 High-speed railway Overhead contact lines Condition monitoring Image processing based measurement
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Research on Distribution of Electromagnetic Environment around Substations and Optimization Layout of On-line Monitoring 被引量:1
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作者 Li Peiming Xiao Jun Wang Wenjin 《Meteorological and Environmental Research》 CAS 2019年第6期60-63,共4页
The characteristics and distribution law of electromagnetic environment around substations with different levels of voltage were studied,and the main influencing factors were discussed. Meanwhile,a scheme for locating... The characteristics and distribution law of electromagnetic environment around substations with different levels of voltage were studied,and the main influencing factors were discussed. Meanwhile,a scheme for locating monitoring points suitable for an on-line monitoring system of electromagnetic environment was proposed. 展开更多
关键词 ON-line monitoring ELECTROMAGNETIC environment SUBSTATION Optimization layout
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黄土-泥岩交界区隧道衬砌受力及围岩破坏模式分析 被引量:1
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作者 郭鑫 辛延甫 +3 位作者 邱成虎 郝敏 杜耀辉 张崇辉 《水力发电》 CAS 2024年第6期32-36,96,共6页
为研究黄土-泥岩交界区隧道衬砌受力特性及围岩破坏模式,以某隧道为工程背景,通过现场监测及数值模拟,对衬砌受力进行了分析。结果表明,围岩压力集中于仰拱,最大值出现在右拱脚;外侧钢拱架应力主要集中于交界面附近拱肩处;钢拱架应力及... 为研究黄土-泥岩交界区隧道衬砌受力特性及围岩破坏模式,以某隧道为工程背景,通过现场监测及数值模拟,对衬砌受力进行了分析。结果表明,围岩压力集中于仰拱,最大值出现在右拱脚;外侧钢拱架应力主要集中于交界面附近拱肩处;钢拱架应力及二衬混凝土应变受混凝土强度发展影响较大,衬砌施作初期,混凝土及拱架均承受较大压应力,随着混凝土强度逐渐提高,应力逐渐减小,仰拱处出现拉应力;围岩塑性区主要分布于交界面附近拱肩及仰拱位置;地下水沿边墙破碎围岩渗流并汇集于仰拱,基底泥岩塑性区易扩大。研究结果可为黄土-泥岩交界地层隧道设计与施工提供参考。 展开更多
关键词 隧道 交界地层 衬砌 破坏模式 受力分析 现场监测 数值模拟
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Design of Power Supply for On-line Monitoring System of Transmission Lines
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作者 Kai Chen Zi-jian Zhao +2 位作者 Yu-ning Zhang Yang-chun Cheng Yuan Dai 《Energy and Power Engineering》 2013年第4期570-574,共5页
This paper uses CT to gain the energy directly from the high-voltage transmission line, to address the problem of power supply for monitoring system in high voltage side of transmission line. The draw-out power coil c... This paper uses CT to gain the energy directly from the high-voltage transmission line, to address the problem of power supply for monitoring system in high voltage side of transmission line. The draw-out power coil can induce voltage from the transmission line, using single-chip microcomputer to analog and output PMW wave to control the charging module, provides a stable 3.4 V DC voltage to the load, and solve the problem of easy saturating of core. The power supply based on this kind of draw-out power coil has undergone the overall testing, and it is verified-showing that it can properly work in a non-saturated status within the current range of 50 - 1000 A, and provide a stable output. The equipment also design protection circuit to improve the reliability to avid the impacts of the impulse current or short-circuit current. It effectively solves the problem of power supply for On-line Monitoring System of Transmission. 展开更多
关键词 monitoring System POWER Supply of HIGH-VOLTAGE Transmission line Draw-out POWER Coil SINGLE-CHIP MICROCOMPUTER
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On-line monitoring of dissolved gas-in-oil with FTIR spectra 被引量:1
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作者 XianyongLiu YunluoLiu LiYue 《Journal of University of Science and Technology Beijing》 CSCD 2003年第4期65-68,共4页
To overcome the disadvantages of conventional DGA (dissolved gas-in-oil)analysis using gas chromatography and other electrochemical sensors, initial researches werecompleted to realize on-line monitoring of dissolved ... To overcome the disadvantages of conventional DGA (dissolved gas-in-oil)analysis using gas chromatography and other electrochemical sensors, initial researches werecompleted to realize on-line monitoring of dissolved gas-in-oil of power transformers using FTIR(Fourier Transform InfraRed) spectroscopy. Gas cell method is used to determine the characteristicabsorption peaks of each diagnostic gas; simple and novel devices and procedures were designed inorder to get measurable samples and spectra of mixed diagnostic gases with known concentration aretaken using long optical path gas cell. The range of wavelength is estimated to be 3.0-13.9 mum fromexperimental spectra data. Hence the corresponding sampling frequency range should be in 536-4288Hz and usable optical materials are suggested. It is concluded that a resolution of 10 cm^(-1) maywell satisfy the monitoring of all diagnostic gases and water content except hydrogen, and thelowest detection limit may be as low as 2Xl0^(-8) to acetylene with a 2.4-meter-long optical length. 展开更多
关键词 FTIR power transformer dissolved gas-in-oil on-line monitoring INFRAREDSPECTRA
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Mechanics Analysis of Overhead Transmission Lines Based On-line Monitoring
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作者 Lili Dai Yongli Zhu Zehui Liang 《Open Journal of Applied Sciences》 2013年第2期1-4,共4页
At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the p... At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the parameters that tension sensors and angle sensors on suspended points detect, and combines with the parameters of the wire itself, and also considers the deflection angel of wires due to wind. In this model, mechanics parameters of wires are turned into the new coordinate plane after deflection angel of wires due to wind, or windage yaw plane. A statics tension balance equation is built in the vertical direction of the new windage yaw plane. According to the theoretical analysis and algorithm, we verify the accuracy of this newly developed mechanical calculation model. 展开更多
关键词 OVERHEAD Transmission line ON-line monitoring Mechanical ANALYSIS Tension ANGLE ICING Windage Yaw
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甲醇制烯烃反-再系统衬里损坏原因分析及解决办法
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作者 赵亚伟 苟荣恒 +1 位作者 何源 潘海涛 《现代化工》 CAS CSCD 北大核心 2024年第S01期345-350,共6页
在甲醇制烯烃装置中,反应再生系统(反-再系统)是整个装置的核心单元。反-再系统设备结构趋于大型化、异型化、运行长周期化,由衬里冲刷、脱落、内构件磨损造成的非计划停工是制约甲醇制烯烃装置连续运行的瓶颈之一。结合某厂目前反-再... 在甲醇制烯烃装置中,反应再生系统(反-再系统)是整个装置的核心单元。反-再系统设备结构趋于大型化、异型化、运行长周期化,由衬里冲刷、脱落、内构件磨损造成的非计划停工是制约甲醇制烯烃装置连续运行的瓶颈之一。结合某厂目前反-再系统衬里存在的损伤、失效的不同情况,从规范工艺操作、衬里型号选材、施衬方式、养护、测温等方面出发,提出针对性的解决方法,保证了衬里在使用中的质量;对衬里已发生的热点、泄漏点提出有效的紧急处置措施,避免衬里泄漏点扩大,危及人员生命安全,降低了装置紧急停产停工带来的不可控风险。 展开更多
关键词 甲醇制烯烃 -再系统 衬里 损坏 泄漏 施工方法 监测
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State Maintenance of On-line Monitoring for High Voltage Equipment
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《Electricity》 1997年第2期35-36,共2页
关键词 line State Maintenance of On-line monitoring for High Voltage Equipment
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Vibration Monitoring and Diagnosis of Pipe-line Pumps on Offshore Platforms
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作者 Zheng Wen Technological Faculty of Maintenance Engineering Guangzhou University, Guangzhou 510091, P.R.China 《International Journal of Plant Engineering and Management》 1997年第3期6-10,共5页
This paper presents the applications of vibration monitoring and a diagnosis technique on the predictive maintenance of pipe line pumps on offshore platforms. The monitored ten pumps are distributed on the past three... This paper presents the applications of vibration monitoring and a diagnosis technique on the predictive maintenance of pipe line pumps on offshore platforms. The monitored ten pumps are distributed on the past three petroleum platforms of the CACT (C: China offshove Southern; A: Agip; C: Chivron; T: Texaco) Operation Group in the Huizhou oil field. By the periodical vibration survey in recent three years, the typical faults and the vibration features of these pumps have been summarized, which set up the basis for efficient predictive maintenance of this key equipment offshore. 展开更多
关键词 vibration monitoring fault diagnosis pipe line pump petroleum platform
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On-line Condition Monitoring and Diagnostic Network System for Rotating Machine Set 被引量:1
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作者 Li Fucai, He Zhengjia, Zi Yanyang School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, P. R. China 《International Journal of Plant Engineering and Management》 2000年第4期136-141,共6页
Several industrial computers and a server are combined to set up the on-line monitoring and diagnostic system of turbo-generator sets. The main function of the system is to monitor machine sets' running condition.... Several industrial computers and a server are combined to set up the on-line monitoring and diagnostic system of turbo-generator sets. The main function of the system is to monitor machine sets' running condition. Through analyzing running data, technicians can detect whether there exist faults and where they occur. To share and transmit the dynamic information of the turbo-generator sets, a distributed network system is introduced. NetWare network operating system is used in the LAN (Local Area Network) system. The LAN is extended to realize the sharing of data and remote transmission of information. Furthermore, functions of monitoring and diagnostic clients are listed. 展开更多
关键词 rotating machine set on-line monitoring and diagnostic network system
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On-line Monitoring of Insulation Dielectric Loss Factor Based on Balance Principle
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作者 Tianxiang CHEN Zhenhua SHAO +1 位作者 Shaozhen QIN Hong TIAN 《电力系统自动化》 EI CSCD 北大核心 2013年第21期180-183,共4页
关键词 介质损耗因数 平衡原则 在线监测 绝缘 相位误差 高精确度 电流传感器 位移传感器
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On-line monitoring of insulation quality of high voltage electric power equipment
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作者 SUN He-yi, ZHAO Xue-zeng, NIE Peng, BAI Jing-feng, YANG Yan-zhu (Harbin Institute of Technology, Harbin 150001, China) 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第S1期77-80,共4页
Discusses on-line monitoring of electric parameters, such as dielectric loss, divulging current, equivalent capacitance and running voltage, and presents an on-line monitoring system of insulation quality, based on mo... Discusses on-line monitoring of electric parameters, such as dielectric loss, divulging current, equivalent capacitance and running voltage, and presents an on-line monitoring system of insulation quality, based on monitoring divulging current and dielectric loss of high voltage equipment, and its advantages, such as helping people to discover the hidden problems in a timely manner, to reduce power cut and overhaul and to improve security of power supply. 展开更多
关键词 INSULATION CAPABILITY HIGH-VOLTAGE EQUIPMENT ON-line monitoring data PROCESSING
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Research Progress of On-line Monitoring Technology for Electromagnetic Environment of Power Transmission and Transformation Projects
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作者 Li Peiming Zhou Jian +2 位作者 Xiao Jun Wang Wenjin Ge Xiaoyang 《Meteorological and Environmental Research》 CAS 2019年第6期67-71,共5页
Based on the collection of relevant literature and cases,the research and application status of on-line monitoring technology for electromagnetic environment of power transmission and transformation projects at home a... Based on the collection of relevant literature and cases,the research and application status of on-line monitoring technology for electromagnetic environment of power transmission and transformation projects at home and abroad were introduced.Moreover,the problems existing in the on-line monitoring of electromagnetic environment were expounded,and the development prospect was forecasted. 展开更多
关键词 ON-line monitoring TECHNOLOGY ELECTROMAGNETIC environment Power TRANSMISSION and TRANSFORMATION PROJECT
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Wireless Distributed Monitoring Terminal Used for On-Line Application
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作者 Fenggui Wang Lin Zhang +1 位作者 Zhongmin Wang Yanbo Zhang 《Communications and Network》 2013年第3期549-553,共5页
A wireless distributed monitoring terminal was designed with embedded Linux used on the basis of ARM board, and an application program was developed for data collection, processing and transmission. Data were collecte... A wireless distributed monitoring terminal was designed with embedded Linux used on the basis of ARM board, and an application program was developed for data collection, processing and transmission. Data were collected from the surrounding environment and transmitted to a server via WLAN in the form of Extensible Markup Language (XML) stream, so the terminal had good flexibility to be compatible with different sensors, network devices and information systems from multiple manufacturers. 展开更多
关键词 On-line monitorING DISTRIBUTED monitorING Extensible MARKUP Language (XML) STREAM WIRELESS TERMINAL
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Distributed On-line Monitoring System for Sheath Circulating Current of Cross-linked Power Cables
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作者 MENG Yong-peng PENG Fa-dong +3 位作者 YAN Li CHEN Xiao-lin CHENG Yong-hong LIU Jing 《高电压技术》 EI CAS CSCD 北大核心 2009年第3期533-538,共6页
关键词 供电系统 电缆 信号采集 在线监测系统
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