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Optical Label-Based Cost-Effective DWDM Optical Network Performance Monitoring Using Low-Bandwidth PD with Novel SRS Mitigation DSP 被引量:1
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作者 Jinhao Du Tao Yang +1 位作者 Sheping Shi Xue Chen 《China Communications》 SCIE CSCD 2023年第7期203-216,共14页
Large-scale dense wavelength division multiplexing(DWDM)multi-channel performance monitoring is one of the indispensable technologies for the flexible optical networks.The existing Labelbased monitoring scheme require... Large-scale dense wavelength division multiplexing(DWDM)multi-channel performance monitoring is one of the indispensable technologies for the flexible optical networks.The existing Labelbased monitoring scheme requires expensive optical demultiplexing components/equipment to avoid the influence of stimulated Raman scattering(SRS),which is not only costly and bulky,but also could not monitor the wavelength channels simultaneously.In this paper,a low-cost,high-accuracy monitoring scheme based on Optical Label Method is proposed for DWDM networks,where the optical channel power and node identification(ID),as the main monitoring targets that both can indicate or evaluate the channel connection status,could be efficiently monitored.In the scheme,a novel digital signal processing(DSP)method of SRS mitigation is proposed and demonstrated,and an asynchronous code-division multiple access(A-CDMA)based digital label encoding and decoding method is adopted to distinguish the node ID so that channel initial added node can be accurately verified,thereby wavelength connection status can be reliably monitored by combining the channel power and node ID information.The simulation results show that each wavelength channel power and node ID can be accurately monitored only by low bandwidth photoelectric detector(PD)under the condition of 80 wavelengths and 10 spans at C-band. 展开更多
关键词 optical label stimulated raman scattering(SRS) optical performance monitoring(OPM)
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Optimal Machine Learning Enabled Performance Monitoring for Learning Management Systems
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作者 Ashit Kumar Dutta Mazen Mushabab Alqahtani +2 位作者 Yasser Albagory Abdul Rahaman Wahab Sait Majed Alsanea 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2277-2292,共16页
Learning Management System(LMS)is an application software that is used in automation,delivery,administration,tracking,and reporting of courses and programs in educational sector.The LMS which exploits machine learning... Learning Management System(LMS)is an application software that is used in automation,delivery,administration,tracking,and reporting of courses and programs in educational sector.The LMS which exploits machine learning(ML)has the ability of accessing user data and exploit it for improving the learning experience.The recently developed artificial intelligence(AI)and ML models helps to accomplish effective performance monitoring for LMS.Among the different processes involved in ML based LMS,feature selection and classification processesfind beneficial.In this motivation,this study introduces Glowworm-based Feature Selection with Machine Learning Enabled Performance Monitoring(GSO-MFWELM)technique for LMS.The key objective of the proposed GSO-MFWELM technique is to effectually monitor the performance in LMS.The pro-posed GSO-MFWELM technique involves GSO-based feature selection techni-que to select the optimal features.Besides,Weighted Extreme Learning Machine(WELM)model is applied for classification process whereas the parameters involved in WELM model are optimallyfine-tuned with the help of May-fly Optimization(MFO)algorithm.The design of GSO and MFO techniques result in reduced computation complexity and improved classification performance.The presented GSO-MFWELM technique was validated for its performance against benchmark dataset and the results were inspected under several aspects.The simulation results established the supremacy of GSO-MFWELM technique over recent approaches with the maximum classification accuracy of 0.9589. 展开更多
关键词 Learning management system data mining performance monitoring machine learning feature selection
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Development and Application of On-Line Corrosion Monitoring Device for Condenser Tube 被引量:1
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作者 曹杰玉 宋敬霞 +2 位作者 汪德良 龙国军 孙本达 《Electricity》 2004年第2期31-35,共5页
This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current te... This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current test, which enable the monitoring result to be consistent with the corrosion of actual condenser tubes. Localized corrosion rate of condenser tubes can be measured indirectly by a galvanic couple made up of tube segments with and without pits. Using this technology, corrosion problems can be found in time and accurately, and anticorrosive measures be made more economic and effective. Applications in two power plants showed the corrosion measurements are fast and accurate. 展开更多
关键词 condenser tube CORROSION on-line monitoring INSTRUMENTATION
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On-Line Monitoring of Cutting Tool Fracture & Wear
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作者 王信义 肖定国 宋新民 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期139-150,共12页
A technique of detecting cutting tool fracture and ultimate wear by si- multaneously monitoring both the spindle motor current and cutting process related acoustic emission(AE)in the cutting process is reported.The te... A technique of detecting cutting tool fracture and ultimate wear by si- multaneously monitoring both the spindle motor current and cutting process related acoustic emission(AE)in the cutting process is reported.The technique can detect breakage of drills having diameter over 0.8mm,turning cutter crack of area over 0.2mm,and the ultimate wear.The principle,system construction,experimental method and result of the technique are discussed.The ratio of success in detection approaches 96% or higher. 展开更多
关键词 on-line monitoring acoustic emission/tool fracture motor current
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MPDP: A Probabilistic Architecture for Microservice Performance Diagnosis and Prediction
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作者 Talal H.Noor 《Computer Systems Science & Engineering》 2024年第5期1273-1299,共27页
In recent years,container-based cloud virtualization solutions have emerged to mitigate the performance gap between non-virtualized and virtualized physical resources.However,there is a noticeable absence of technique... In recent years,container-based cloud virtualization solutions have emerged to mitigate the performance gap between non-virtualized and virtualized physical resources.However,there is a noticeable absence of techniques for predicting microservice performance in current research,which impacts cloud service users’ability to determine when to provision or de-provision microservices.Predicting microservice performance poses challenges due to overheads associated with actions such as variations in processing time caused by resource contention,which potentially leads to user confusion.In this paper,we propose,develop,and validate a probabilistic architecture named Microservice Performance Diagnosis and Prediction(MPDP).MPDP considers various factors such as response time,throughput,CPU usage,and othermetrics to dynamicallymodel interactions betweenmicroservice performance indicators for diagnosis and prediction.Using experimental data fromourmonitoring tool,stakeholders can build various networks for probabilistic analysis ofmicroservice performance diagnosis and prediction and estimate the best microservice resource combination for a given Quality of Service(QoS)level.We generated a dataset of microservices with 2726 records across four benchmarks including CPU,memory,response time,and throughput to demonstrate the efficacy of the proposed MPDP architecture.We validate MPDP and demonstrate its capability to predict microservice performance.We compared various Bayesian networks such as the Noisy-OR Network(NOR),Naive Bayes Network(NBN),and Complex Bayesian Network(CBN),achieving an overall accuracy rate of 89.98%when using CBN. 展开更多
关键词 Cloud computing microservices monitoring performance QOS DIAGNOSIS PREDICTION Bayesian network
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Business performance monitoring based on web service proxy
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作者 陈再本 邢春晓 +1 位作者 杨吉江 胡庆成 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期413-417,共5页
To provide efficient monitoring of web service-based business processes, a web service proxy (WS- proxy) is developed to monitor business activities by monitoring the enactment of services. WS-proxy is deployed as a... To provide efficient monitoring of web service-based business processes, a web service proxy (WS- proxy) is developed to monitor business activities by monitoring the enactment of services. WS-proxy is deployed as an intermediary between internal business processes and external service providers, and it provides a single point of service access with the functions of message routing and content inspection. By using an XPath engine named WS-filter, performance indicators can be generated from service messages for assessing business performance. In the experiments, the feasibility of WS-proxy is verified and it achieves good performance in the monitoring work. The latency introduced by WS-proxy is only about 15% of the overall latency while extracting performance indicators just consumes less than one third of the processing time. 展开更多
关键词 performance PROCESS monitoring web service PROXY
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Performance Monitoring and Diagnosis of Multivariable Model Predictive Control Using Statistical Analysis 被引量:11
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作者 张强 李少远 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第2期207-215,共9页
A statistic-based benchmark was proposed for performance assessment and monitoring of model predic- tive control; the benchmark was straightforward and achievable by recording a set of output data only when the contro... A statistic-based benchmark was proposed for performance assessment and monitoring of model predic- tive control; the benchmark was straightforward and achievable by recording a set of output data only when the control performance was good according to the user’s selection. Principal component model was built and an auto- regressive moving average filter was identified to monitor the performance; an improved T2 statistic was selected as the performance monitor index. When performance changes were detected, diagnosis was done by model validation using recursive analysis and generalized likelihood ratio (GLR) method. This distinguished the fact that the per- formance change was due to plant model mismatch or due to disturbance term. Simulation was done about a heavy oil fractionator system and good results were obtained. The diagnosis result was helpful for the operator to improve the system performance. 展开更多
关键词 predictive control performance monitoring DIAGNOSIS principal component analysis
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On-line Monitoring for Phosphorus Removal Process and Bacterial Community in Sequencing Batch Reactor 被引量:4
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作者 崔有为 王淑莹 李晶 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期484-492,共9页
For efficient energy consumption and control of effluent quality, the cycle duration for a sequencing batch reactor (SBR) needs to be adjusted by real-time control according to the characteristics and loading of waste... For efficient energy consumption and control of effluent quality, the cycle duration for a sequencing batch reactor (SBR) needs to be adjusted by real-time control according to the characteristics and loading of waste-water. In this study, an on-line information system for phosphorus removal processes was established. Based on the analysis for four systems with different ecological community structures and two operation modes, anaerobic-aerobic process and anaerobic-anaerobic process, the characteristic patterns of oxidation-reduction potential (ORP) and pH were related to phosphorous dynamics in the anaerobic, anoxic and aerobic phases, for determination of the end of phosphorous removal. In the operation mode of anaerobic-aerobic process, the pH profile in the anaerobic phase was used to estimate the relative amount of phosphorous accumulating organisms (PAOs) and glycogen accumulat-ing organisms (GAOs), which is beneficial to early detection of ecology community shifts. The on-line sensor val-ues of pH and ORP may be used as the parameters to adjust the duration for phosphorous removal and community shifts to cope with influent variations and maintain appropriate operation conditions. 展开更多
关键词 on-line monitoring phosphorus removal sequencing batch reactor PH oxidation-reduction potential
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Comparative analysis of online monitoring methods for transformer insulation performance of 330-750kV substation
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作者 子贡 董海鹰 任伟 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期71-77,共7页
The online-monitoring methods for insulation performance of current transformers of 330-750 kV substation are analyzed and compared.The effectiveness and availability of each method are discussed.Main features,advanta... The online-monitoring methods for insulation performance of current transformers of 330-750 kV substation are analyzed and compared.The effectiveness and availability of each method are discussed.Main features,advantages and disadvantages of each method and its corresponding standard are also described. 展开更多
关键词 continuous control insulation performance online monitoring SUBSTATION
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On-line enrichment and determination of polycyclic aromatic hydrocarbons in atmospheric particulates using high performance liquid chromatography with fluorescence as detector 被引量:1
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作者 HASHI Yuki WANG Tian-ran +1 位作者 LI Yue-qi LIN Jin-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第10期1261-1265,共5页
Seven polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulates were determinated by high performance liquid chromatography (HPLC) with fluorescence detector using direction injection and an on-line enri... Seven polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulates were determinated by high performance liquid chromatography (HPLC) with fluorescence detector using direction injection and an on-line enrichment trap column. The method simplified the sample pretreatment, saved time and increased the efficiency. With the on-line trap column, PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency. The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample. The limit of detection was 15.3-39.6 ng/L (S/N=3.3). There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970. Furthermore, it also indicated that the method is available to determine PAHs in atmospheric particulates well. 展开更多
关键词 on-line enrichment on-line trap column high performance liquid chromatography (HPLC) atmospheric particulate polycyclic aromatic hydrocarbons (PAHs)
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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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Contractor Monitoring and Performance of Road Infrastructure Projects in Uganda: A Management Model 被引量:1
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作者 Aloysius Byaruhanga Benon C. Basheka 《Journal of Building Construction and Planning Research》 2017年第1期30-44,共15页
An understanding of the influence of contractor monitoring on performance of road infrastructural projects in Uganda provided an impetus for this study. The objectives of the study were to: assess the relationship bet... An understanding of the influence of contractor monitoring on performance of road infrastructural projects in Uganda provided an impetus for this study. The objectives of the study were to: assess the relationship between contractors monitoring and performance of national road infrastructure projects and the relationship between contractor monitoring components and performance of national road infrastructure projects in Uganda. Purposive sampling was employed in selecting the procurement professionals, engineers and simple random sampling was adopted in selecting private consultants, members of parliament and respondents from the civil society organizations. Data for this study were collected using a closed ended questionnaire and interviews. Some of the major finding from this study include: weak procurement rules which lead to awarding road projects to incompetent contractors;contractor monitoring being handled by unqualified, incompetent and inexperienced professionals;lack of contractors and contract supervisors appraisal system;delay of contractors payments which affects timelines in services delivery;lack of a strong internal project monitoring and evaluation mechanism at the Uganda National Roads Agency (UNRA). The research therefore recommends the establishment of an Independent Public Infrastructure Development and Monitoring Unit by government and adoption of systems that appraise both contractors and contract supervisors with clear disciplinary actions for unsatisfactory performance by the UNRA. 展开更多
关键词 CONTRACTOR monitoring performance of ROADS INFRASTRUCTURE MANAGEMENT Uganda
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Performance evaluation of near real-time condition monitoring in haul trucks 被引量:1
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作者 Hemanth Reddy Alla Robert Hall Derek B.Apel 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2020年第6期909-915,共7页
Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive ... Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive maintenance strategy,which led to the development of condition-based maintenance.Realtime condition monitoring(RTCM)is the ability to perform condition monitoring in real-time and has the ability to alert maintenance and operations of abnormal conditions.These alarms can be used as an indication leading to a problem,and if a suitable corrective action is initiated in time,it could result in significant savings of equipment downtime and repair costs.This study aims to compare some maintenance performance indicators prior to and after implementation of RTCM strategy at a mine site using some tests of statistical significance.The study also indicated the presence of seasonality in the data,and thus the data was deseasonalized and detrended prior to being subjected to the statistical tests.Finally,the results indicated that RTCM strategy has proven to be successful in improving the availability for some of the failure categories chosen in this study. 展开更多
关键词 Haul trucks Real-time condition monitoring performance indicators
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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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Monitoring actual performance of ground source heat pump system using GPRS-based data transmission: A case analysis in Tangshan 被引量:2
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作者 杜红普 孔祥飞 +1 位作者 李敏 齐承英 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1554-1562,共9页
The energy efficiency monitoring is an essential precondition for ground source heat pump system's controlling and energy saving operation. Based on the data monitoring applied in the school building, this work is... The energy efficiency monitoring is an essential precondition for ground source heat pump system's controlling and energy saving operation. Based on the data monitoring applied in the school building, this work is focused on the parameters acquisition and operation analysis of the GSHP system in Tangshan. Results show the average COPs(coefficient of performance) are2.85 and 2.70 in summer and winter, respectively, and heat(cold) unbalance underground existed after whole year operation. The analysis of data also indicates that the direct borehole air-conditioning saved some power consumption obviously in the early stage of summer and energy saving of the GSHP system depended remarkably on its operation and management level. Besides the observation points of ground temperature are laid for a large-scale GSHP system, and the hydraulic balance of the pipes group needs to be concerned specially in safeguarding better reliability. 展开更多
关键词 ground source heat pump monitoring operation performance
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Hellinger distance based probability distribution approach to performance monitoring of nonlinear control systems 被引量:2
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作者 李晨 黄彪 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1945-1950,共6页
Control performance monitoring has attracted great attention in both academia and industry over the past two decades. However, most research efforts have been devoted to the performance monitoring of linear control sy... Control performance monitoring has attracted great attention in both academia and industry over the past two decades. However, most research efforts have been devoted to the performance monitoring of linear control systems, without considering the pervasive nonlinearities(e.g. valve stiction) present in most industrial control systems. In this work, a novel probability distribution distance based index is proposed to monitor the performance of non-linear control systems. The proposed method uses Hellinger distance to evaluate change of control system performance. Several simulation examples are given to illustrate the effectiveness of the proposed method. 展开更多
关键词 Control performance monitoring Kernel density estimation Hellinger distance Nonlinear system
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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 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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Performance Monitoring of the Data-driven Subspace Predictive Control Systems Based on Historical Objective Function Benchmark 被引量:3
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作者 王陆 李柠 李少远 《自动化学报》 EI CSCD 北大核心 2013年第5期542-547,共6页
关键词 预测控制系统 性能监控 数据驱动 子空间 历史 基准 监视控制器 目标函数
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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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