Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128653
A. Šala, J. Konjevod, P. Mostarac, Stipe Gašparini
As new calibration equipment becomes available, there is an increasing demand for calibrations at higher currents and wider frequency ranges of up to 100 kHz and 100 A [1]. In response to this demand, we have expanded our ac-dc capability and developed a new set of standard shunts suitable for measuring currents in laboratories, as well as for use in power electronics applications [2].
{"title":"Precision high power wide bandwidth AC/DC current shunt","authors":"A. Šala, J. Konjevod, P. Mostarac, Stipe Gašparini","doi":"10.1109/SMAGRIMET58412.2023.10128653","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128653","url":null,"abstract":"As new calibration equipment becomes available, there is an increasing demand for calibrations at higher currents and wider frequency ranges of up to 100 kHz and 100 A [1]. In response to this demand, we have expanded our ac-dc capability and developed a new set of standard shunts suitable for measuring currents in laboratories, as well as for use in power electronics applications [2].","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130183167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128657
H. Hegedus, Mario Marković
This paper explains the high electrical resistance measurement method, adjusting the measurement parameters, comparison of several measurement configurations and electrical circuit solutions that increase the accuracy of the measurement.
本文阐述了高电阻测量方法、测量参数的调整、几种测量配置的比较以及提高测量精度的电路解决方案。
{"title":"High resistance measurement based on industrial datalogger","authors":"H. Hegedus, Mario Marković","doi":"10.1109/SMAGRIMET58412.2023.10128657","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128657","url":null,"abstract":"This paper explains the high electrical resistance measurement method, adjusting the measurement parameters, comparison of several measurement configurations and electrical circuit solutions that increase the accuracy of the measurement.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128361848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128688
Arman Ghaderi Baayeh, M. Kleemann
The online estimating of grounding resistances of medium voltage cable sheaths makes it possible to monitor their zero-sequence impedance. This paper proposes a cable grounding resistance estimation method for three-phase single-core cables. The method uses the phasors of measured voltage and currents of the cable sending end and the Pi-model of the cable to estimate the current of the main conductor at the receiving end. Then, using measured currents at the cable's receiving end, the sheaths' grounding resistances at both ends of the cable are calculated. A set of 1600 transient power system simulations proves the method is effective. The error is less than 71 $m$Ω varying short circuits level, X/R ratio, cable loading, voltage unbalance factor, and voltages and currents magnitude error.
{"title":"Estimating grounding resistance of medium voltage cables using measured sheaths current","authors":"Arman Ghaderi Baayeh, M. Kleemann","doi":"10.1109/SMAGRIMET58412.2023.10128688","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128688","url":null,"abstract":"The online estimating of grounding resistances of medium voltage cable sheaths makes it possible to monitor their zero-sequence impedance. This paper proposes a cable grounding resistance estimation method for three-phase single-core cables. The method uses the phasors of measured voltage and currents of the cable sending end and the Pi-model of the cable to estimate the current of the main conductor at the receiving end. Then, using measured currents at the cable's receiving end, the sheaths' grounding resistances at both ends of the cable are calculated. A set of 1600 transient power system simulations proves the method is effective. The error is less than 71 $m$Ω varying short circuits level, X/R ratio, cable loading, voltage unbalance factor, and voltages and currents magnitude error.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124035832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128660
Kristian Knol, T. Benšić, M. Barukčić
During the development of control strategies for permanent magnet synchronous machines (PMSM) used in wind turbines, usage of wide range of simulation allows for more detailed, more safe and less expensive development. This paper presents type of HIL simulation, where instead of using real controller and real-time simulator, two real-time simulators are used and form a co-simulation environment where vector control of PMSM is conducted. The whole process of designing and simulating is a part of model-based design (MBD). The PMSM is described and controller for vector control is derived. Created co-simulation environment with its advantages and problems is described. An experiment with different scenarios is conducted to test created co-simulation.
{"title":"Vector control design and analysis for PMSM using real-time HIL simulation","authors":"Kristian Knol, T. Benšić, M. Barukčić","doi":"10.1109/SMAGRIMET58412.2023.10128660","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128660","url":null,"abstract":"During the development of control strategies for permanent magnet synchronous machines (PMSM) used in wind turbines, usage of wide range of simulation allows for more detailed, more safe and less expensive development. This paper presents type of HIL simulation, where instead of using real controller and real-time simulator, two real-time simulators are used and form a co-simulation environment where vector control of PMSM is conducted. The whole process of designing and simulating is a part of model-based design (MBD). The PMSM is described and controller for vector control is derived. Created co-simulation environment with its advantages and problems is described. An experiment with different scenarios is conducted to test created co-simulation.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129112854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128652
Tomislav Šterc, B. Filipović-Grčić, B. Franc, Krešimir Mesić, Alan Zupan, B. Jurišić
Transmission system operators often use Static Thermal Rating (STR) for maximum allowable thermal rating of Overhead Line (OHL) conductor. Such static thermal limits are usually defined for operation in extreme weather conditions which are rarely achieved in real-world operation. In this paper, based on the weather parameters collected from an automated weather station installed on a transmission tower, the conductor temperature is estimated using newly developed method based on Artificial Neural Network (ANN) and Particle Swarm Optimization (PSO). Calculated temperatures are compared with measured temperatures from Overhead Transmission Line Monitoring (OTLM) device. Correct estimation of OHL conductor temperature leads to better prediction of Dynamic Thermal Rating (DTR).
{"title":"Particle swarm optimization trained neural network for overhead line conductor temperature prediction","authors":"Tomislav Šterc, B. Filipović-Grčić, B. Franc, Krešimir Mesić, Alan Zupan, B. Jurišić","doi":"10.1109/SMAGRIMET58412.2023.10128652","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128652","url":null,"abstract":"Transmission system operators often use Static Thermal Rating (STR) for maximum allowable thermal rating of Overhead Line (OHL) conductor. Such static thermal limits are usually defined for operation in extreme weather conditions which are rarely achieved in real-world operation. In this paper, based on the weather parameters collected from an automated weather station installed on a transmission tower, the conductor temperature is estimated using newly developed method based on Artificial Neural Network (ANN) and Particle Swarm Optimization (PSO). Calculated temperatures are compared with measured temperatures from Overhead Transmission Line Monitoring (OTLM) device. Correct estimation of OHL conductor temperature leads to better prediction of Dynamic Thermal Rating (DTR).","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121116312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128656
P. Mostarac, Leon Kahlina, Jasna Janković, Ž. Ilić, G. Šišul, Alan Šala
This paper describes and proposed the conceptual framework for automated system for berth allocation in the marina. The method for reconstruction and registration number detection are based on reconstruction of 3D scene using calibrated stereovision system. Process of extraction of data is based on multi base searching protocol. The correspondence between all participants in the use of the marina is fully described and their interaction through the berthing aid system is defined. A brief analysis of the communication technologies on which the berthing aid system works is presented.
{"title":"Smart marina: concept of stereovision based berthing aid system","authors":"P. Mostarac, Leon Kahlina, Jasna Janković, Ž. Ilić, G. Šišul, Alan Šala","doi":"10.1109/SMAGRIMET58412.2023.10128656","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128656","url":null,"abstract":"This paper describes and proposed the conceptual framework for automated system for berth allocation in the marina. The method for reconstruction and registration number detection are based on reconstruction of 3D scene using calibrated stereovision system. Process of extraction of data is based on multi base searching protocol. The correspondence between all participants in the use of the marina is fully described and their interaction through the berthing aid system is defined. A brief analysis of the communication technologies on which the berthing aid system works is presented.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115665643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128661
Matija Varga, Nikola Turk, Dominik Cikač, N. Bulić
This paper presents an optimization approach for the switching angles used in medium voltage 3-level Neutral Point Clamped (NPC) converters with the active front end. Medium voltage (MV) drives use low switching frequencies to reduce the converters' switching losses. This fact limits the number of available switching angles that can be used. Therefore, 5 and 7 pulses (i.e., switching angles) in quarter-wave symmetry are considered in this research. Insulated Gate Bipolar Transistors (IGBTs) or Integrated Gate Commutated Thyristors (IGCTs), which are used in MV drives because of their capability to provide high power density, present obstacles in the optimization. Their high minimum on-time and dead time, which must be considered during the optimization process, are among the challenges associated with the use of IGBTs or IGCTs in MV drives. On-time refers to the duration in which the IGBT is conducting current, while dead-time refers to the interval in which the IGBT is turned off and cannot conduct current. The dead time is introduced to prevent shoot-through currents in the inverter circuit, which can cause damage to the IGBTs and other components. This research aims to improve the switching angles of pulse patterns to minimize low-order harmonics in a wide range of modulation index while meeting all the mentioned requirements and generating the desired fundamental harmonic. To achieve this, a modulation technique called Selective Harmonic Elimination (SHE) Pulse-Width Modulation (PWM) has been employed, which effectively reduces the low-order harmonic distortion caused by converters. The optimization process is performed using open-source optimization tools in the Julia programming language. The research results demonstrate that the proposed approach can effectively optimize the pulse pattern angles of medium voltage 3-level NPC converters, resulting in improved power quality and reduced harmonic distortion while ensuring the continuity of switching angles.
{"title":"Pulse Pattern Optimization for Medium Voltage 3-Level NPC Converter Using Open Source Optimization Tools in Julia","authors":"Matija Varga, Nikola Turk, Dominik Cikač, N. Bulić","doi":"10.1109/SMAGRIMET58412.2023.10128661","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128661","url":null,"abstract":"This paper presents an optimization approach for the switching angles used in medium voltage 3-level Neutral Point Clamped (NPC) converters with the active front end. Medium voltage (MV) drives use low switching frequencies to reduce the converters' switching losses. This fact limits the number of available switching angles that can be used. Therefore, 5 and 7 pulses (i.e., switching angles) in quarter-wave symmetry are considered in this research. Insulated Gate Bipolar Transistors (IGBTs) or Integrated Gate Commutated Thyristors (IGCTs), which are used in MV drives because of their capability to provide high power density, present obstacles in the optimization. Their high minimum on-time and dead time, which must be considered during the optimization process, are among the challenges associated with the use of IGBTs or IGCTs in MV drives. On-time refers to the duration in which the IGBT is conducting current, while dead-time refers to the interval in which the IGBT is turned off and cannot conduct current. The dead time is introduced to prevent shoot-through currents in the inverter circuit, which can cause damage to the IGBTs and other components. This research aims to improve the switching angles of pulse patterns to minimize low-order harmonics in a wide range of modulation index while meeting all the mentioned requirements and generating the desired fundamental harmonic. To achieve this, a modulation technique called Selective Harmonic Elimination (SHE) Pulse-Width Modulation (PWM) has been employed, which effectively reduces the low-order harmonic distortion caused by converters. The optimization process is performed using open-source optimization tools in the Julia programming language. The research results demonstrate that the proposed approach can effectively optimize the pulse pattern angles of medium voltage 3-level NPC converters, resulting in improved power quality and reduced harmonic distortion while ensuring the continuity of switching angles.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121891701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128662
F. Vukovic, V. Milardić, B. Filipović-Grčić, N. Stipetić, B. Franc, Dominik Milos
A lightning current measurement system for wind turbines was developed and tested in the High Voltage Laboratory at the Faculty of Electrical Engineering and Computing, University of Zagreb, to determine actual distributions of lightning current parameters in a particular wind turbine area. The output of the measurement system is a waveform of lightning current. The measurement system consists of two current sensors with different frequency and amplitude ranges and a real-time controller with two digitizers and a GPS module. The current sensors are Rogowski coils connected to integrators with coaxial cables. The prototype was installed on a wind turbine in a high winter lightning activity area. The current stage of development involves integrating the high-speed camera into the prototype measurement system to obtain the visual confirmation of the waveform measurements and help categorize lightning strikes into downward or upward strikes. The camera control application was developed in LabVIEW. The camera was set to trigger by the real-time controller. Also, a redundant trigger occurs when there is a change in motion in the camera frame in case the prototype measurement system fails to register a lightning strike and therefore fails to send a trigger signal to the camera. The camera control application was tested in the High Voltage Laboratory by recording a flashover in a spark gap and a flashover on the insulator.
{"title":"Incorporating a High-speed Camera in the Lightning Current Measurement System for Wind Turbines","authors":"F. Vukovic, V. Milardić, B. Filipović-Grčić, N. Stipetić, B. Franc, Dominik Milos","doi":"10.1109/SMAGRIMET58412.2023.10128662","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128662","url":null,"abstract":"A lightning current measurement system for wind turbines was developed and tested in the High Voltage Laboratory at the Faculty of Electrical Engineering and Computing, University of Zagreb, to determine actual distributions of lightning current parameters in a particular wind turbine area. The output of the measurement system is a waveform of lightning current. The measurement system consists of two current sensors with different frequency and amplitude ranges and a real-time controller with two digitizers and a GPS module. The current sensors are Rogowski coils connected to integrators with coaxial cables. The prototype was installed on a wind turbine in a high winter lightning activity area. The current stage of development involves integrating the high-speed camera into the prototype measurement system to obtain the visual confirmation of the waveform measurements and help categorize lightning strikes into downward or upward strikes. The camera control application was developed in LabVIEW. The camera was set to trigger by the real-time controller. Also, a redundant trigger occurs when there is a change in motion in the camera frame in case the prototype measurement system fails to register a lightning strike and therefore fails to send a trigger signal to the camera. The camera control application was tested in the High Voltage Laboratory by recording a flashover in a spark gap and a flashover on the insulator.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129008209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128651
T. Benšić, K. Miličević, D. Vinko, M. Barukčić
The paper presents a scaled laboratory experimental model of ferroresonant circuit designed for detailed investigation of the ferroresonance phenomena. To enable accurate ferroresonance examination, the system is expanded with programmable voltage source and fully automated test system using hardware-in -the-loop methodology.
{"title":"Laboratory Experimental System for Ferroresonance Analysis","authors":"T. Benšić, K. Miličević, D. Vinko, M. Barukčić","doi":"10.1109/SMAGRIMET58412.2023.10128651","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128651","url":null,"abstract":"The paper presents a scaled laboratory experimental model of ferroresonant circuit designed for detailed investigation of the ferroresonance phenomena. To enable accurate ferroresonance examination, the system is expanded with programmable voltage source and fully automated test system using hardware-in -the-loop methodology.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117321106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-24DOI: 10.1109/SMAGRIMET58412.2023.10128655
B. Jurišić, T. Zupan, Marin Schönberger, Ljupko Teklic, Goran Levačić
Every transmission system operator needs to be able to provide its services reliably and cost-effectively. In order to determine the state of the vital electrical equipment in service, two main approaches are nowadays being used: periodic data provided through a set of defined diagnostic measurements and online data that originates from modern monitoring systems. Modern guidelines suggest combining these two datasets in order to have a more economic and technically more detailed insight into the behavior of equipment, as well as providing a number of additional benefits, such as increasing the reliability of the power supply, detailed planning and efficient upgrade of the power network. This paper presents guidelines on how to implement such a solution and shows the advantages of using this type of intelligent condition monitoring for transmission system operators' fleet asset management.
{"title":"Advantages of Using Diagnostic and Monitoring Data for Intelligent Condition Monitoring of Power Network Equipment","authors":"B. Jurišić, T. Zupan, Marin Schönberger, Ljupko Teklic, Goran Levačić","doi":"10.1109/SMAGRIMET58412.2023.10128655","DOIUrl":"https://doi.org/10.1109/SMAGRIMET58412.2023.10128655","url":null,"abstract":"Every transmission system operator needs to be able to provide its services reliably and cost-effectively. In order to determine the state of the vital electrical equipment in service, two main approaches are nowadays being used: periodic data provided through a set of defined diagnostic measurements and online data that originates from modern monitoring systems. Modern guidelines suggest combining these two datasets in order to have a more economic and technically more detailed insight into the behavior of equipment, as well as providing a number of additional benefits, such as increasing the reliability of the power supply, detailed planning and efficient upgrade of the power network. This paper presents guidelines on how to implement such a solution and shows the advantages of using this type of intelligent condition monitoring for transmission system operators' fleet asset management.","PeriodicalId":286515,"journal":{"name":"2023 4th International Conference on Smart Grid Metrology (SMAGRIMET)","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116595104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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