Pub Date : 2013-04-23DOI: 10.1109/ICIT.2013.6505730
M. Ferdosian, H. Abdi, A. Bazaei
There is a continuously growing demand for wind power generation capacity. This situation forces the revision of the grid codes requirements, to remain connected during grid faults, i.e., to ride through the faults, and contribute to system stability during fault condition. In a typical fault condition, the voltage at the Point of Common Coupling (PCC) drops below 80% immediately and the rotor speed of induction generators becomes unstable. In this paper, Unified Power Flow Controller (UPFC) is used to improve the low voltage ride- through (LVRT) of wind energy conversion system (WECS) and to damp the rotor speed oscillations of induction generator under fault conditions. By controlling the UPFC as a virtual inductor, we aims to increase the voltage at the terminals of the wind energy conversion system (WECS) and thereby mitigate the destabilizing electrical torque and power during the fault. The WECS is considered as a fixed-speed system, equipped with a squirrel-cage induction generator. The simulation results show that UPFC can improve the LVRT and rotor stability of the WECS.
{"title":"Improved dynamic performance of wind energy conversion system by UPFC","authors":"M. Ferdosian, H. Abdi, A. Bazaei","doi":"10.1109/ICIT.2013.6505730","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505730","url":null,"abstract":"There is a continuously growing demand for wind power generation capacity. This situation forces the revision of the grid codes requirements, to remain connected during grid faults, i.e., to ride through the faults, and contribute to system stability during fault condition. In a typical fault condition, the voltage at the Point of Common Coupling (PCC) drops below 80% immediately and the rotor speed of induction generators becomes unstable. In this paper, Unified Power Flow Controller (UPFC) is used to improve the low voltage ride- through (LVRT) of wind energy conversion system (WECS) and to damp the rotor speed oscillations of induction generator under fault conditions. By controlling the UPFC as a virtual inductor, we aims to increase the voltage at the terminals of the wind energy conversion system (WECS) and thereby mitigate the destabilizing electrical torque and power during the fault. The WECS is considered as a fixed-speed system, equipped with a squirrel-cage induction generator. The simulation results show that UPFC can improve the LVRT and rotor stability of the WECS.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133095967","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505865
R. Bartz
This paper describes an approach to combine standards specified for the automotive test data management with the widely used Unified Modeling Language (UML). The major challenges in the automotive test data management domain include coping with a huge amount of data produced, considering their long lifetime, and trying to re-use as much as possible of the already acquired knowledge. For this purpose the automotive standards organization ASAM (Association for Standardization of Automation and Measuring Systems) has specified a storage standard called Open Data Services (ODS), which allows users to design data models fitted to their specific needs while keeping general classification information for generic use. On the other hand, object oriented concepts have evolved in the software technology domain, and UML has emerged as the most important standard to specify software-based systems. Given the similarities between the goals of ODS and aspects of UML that describe the static parts of a software system, this paper proposes a mapping between these two technologies.
{"title":"Mapping data models of the standardized automotive testing data storage to the unified modeling language","authors":"R. Bartz","doi":"10.1109/ICIT.2013.6505865","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505865","url":null,"abstract":"This paper describes an approach to combine standards specified for the automotive test data management with the widely used Unified Modeling Language (UML). The major challenges in the automotive test data management domain include coping with a huge amount of data produced, considering their long lifetime, and trying to re-use as much as possible of the already acquired knowledge. For this purpose the automotive standards organization ASAM (Association for Standardization of Automation and Measuring Systems) has specified a storage standard called Open Data Services (ODS), which allows users to design data models fitted to their specific needs while keeping general classification information for generic use. On the other hand, object oriented concepts have evolved in the software technology domain, and UML has emerged as the most important standard to specify software-based systems. Given the similarities between the goals of ODS and aspects of UML that describe the static parts of a software system, this paper proposes a mapping between these two technologies.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133121759","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505687
F. Alrifai
Closed-loop torque and speed control of the brushless permanent magnet (BLPM) machine requires rotor positional information to control the associated power electronic inverter. Rotor position information is acquired by position sensors or position sensorless schemes. These position sensors increase the cost and size of the BLPM drive systems and make it prone to mechanical failure due to the sensitive nature of typical rotor position sensing devices. Many researchers are investigating position sensorless schemes to address these points, however most position sensorless techniques behave poorly at stand-still and low speeds (0-300rpm); they also behave poorly due to the fact that they estimate load torque which can be difficult in undefined load applications due to control parameter changes. This paper proposes a novel idea to achieve closed-loop control of a BLPM machine by using measured shaft torque feedback from an integrated, low-cost, torque surface acoustic torque (SAW) transducer.
{"title":"Control of a BLPM machine using an integrated torque sensor in place of a rotor position sensor","authors":"F. Alrifai","doi":"10.1109/ICIT.2013.6505687","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505687","url":null,"abstract":"Closed-loop torque and speed control of the brushless permanent magnet (BLPM) machine requires rotor positional information to control the associated power electronic inverter. Rotor position information is acquired by position sensors or position sensorless schemes. These position sensors increase the cost and size of the BLPM drive systems and make it prone to mechanical failure due to the sensitive nature of typical rotor position sensing devices. Many researchers are investigating position sensorless schemes to address these points, however most position sensorless techniques behave poorly at stand-still and low speeds (0-300rpm); they also behave poorly due to the fact that they estimate load torque which can be difficult in undefined load applications due to control parameter changes. This paper proposes a novel idea to achieve closed-loop control of a BLPM machine by using measured shaft torque feedback from an integrated, low-cost, torque surface acoustic torque (SAW) transducer.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115777441","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505797
M. Taberer, A. Roberts, R. T. Harris, W. Phipps
The research work conducted in this paper is the evaluation of real time values obtained using two OMICRON 356's at two independent locations and implementing them as recorder devices in Eskom's power system. A derived model within DIgSILENT is created and EMT studies are performed and compared to the real time values obtained. Transformers are normally closed via an auxiliary contact. Thus by applying system voltage at a random instant in time on the transformer windings result in a high transient magnetizing inrush current which causes high orders of 2nd harmonic currents to flow under no load conditions. A philosophy to mitigating these currents is to energize the transformer by controlling the circuit breaker closing times such that the magnetic flux produced in the windings corresponds to the prospective flux in the core. Transients produced can cause nuisance tripping's at the particular location where the respective transformers are energized. OMICRON EnerLyzer is the software tool used for the Comtrade recordings at both locations. Two “real time” case studies are evaluated using OMICRON EnerLyzer and TOP software. Results are formulated and then evaluated against a derived Electromagnetic transient model using DIgSILENT software.
{"title":"Transient analysis of erroneous tripping at Grassridge SVC","authors":"M. Taberer, A. Roberts, R. T. Harris, W. Phipps","doi":"10.1109/ICIT.2013.6505797","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505797","url":null,"abstract":"The research work conducted in this paper is the evaluation of real time values obtained using two OMICRON 356's at two independent locations and implementing them as recorder devices in Eskom's power system. A derived model within DIgSILENT is created and EMT studies are performed and compared to the real time values obtained. Transformers are normally closed via an auxiliary contact. Thus by applying system voltage at a random instant in time on the transformer windings result in a high transient magnetizing inrush current which causes high orders of 2nd harmonic currents to flow under no load conditions. A philosophy to mitigating these currents is to energize the transformer by controlling the circuit breaker closing times such that the magnetic flux produced in the windings corresponds to the prospective flux in the core. Transients produced can cause nuisance tripping's at the particular location where the respective transformers are energized. OMICRON EnerLyzer is the software tool used for the Comtrade recordings at both locations. Two “real time” case studies are evaluated using OMICRON EnerLyzer and TOP software. Results are formulated and then evaluated against a derived Electromagnetic transient model using DIgSILENT software.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134128673","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505712
S. González, M. Valla
The power quality (PQ) in distribution systems is principally affected by the pollution introduced by the customers. It is necessary to protect the sensitive loads from disturbances such as sags, swells, source voltage imbalances, etc. The actual solution for this case is to employ a dynamic voltage restorer (DVR) device. The use of multilevel inverters in medium voltage applications is a good solution. In particular, the cascaded asymmetric multilevel converter (CAMC) appears as a very attractive alternative among the 5-level converters for this application. The design of the CAMC as a DVR in a medium voltage distribution power system is presented in this paper. The model and the control strategy are discussed in d-q coordinates synchronous with the source voltage. The performance of the proposed compensator is tested with SPICE simulations.
{"title":"A DVR built with a 5-level cascade asymmetric multilevel converter","authors":"S. González, M. Valla","doi":"10.1109/ICIT.2013.6505712","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505712","url":null,"abstract":"The power quality (PQ) in distribution systems is principally affected by the pollution introduced by the customers. It is necessary to protect the sensitive loads from disturbances such as sags, swells, source voltage imbalances, etc. The actual solution for this case is to employ a dynamic voltage restorer (DVR) device. The use of multilevel inverters in medium voltage applications is a good solution. In particular, the cascaded asymmetric multilevel converter (CAMC) appears as a very attractive alternative among the 5-level converters for this application. The design of the CAMC as a DVR in a medium voltage distribution power system is presented in this paper. The model and the control strategy are discussed in d-q coordinates synchronous with the source voltage. The performance of the proposed compensator is tested with SPICE simulations.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"347 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134524878","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505912
J. Sobolewski, L. Grzesiak
The paper investigates possible advantages from using nonlinear adaptive ANN (Artificial Neural Network)-based controller in a control system of autonomous variable speed electrical energy source with internal combustion engine. The speed is adjusted automatically as a function of load power demand. When the system is in a light or no load condition, the Main Voltage Controller automatically reduces the engine speed in order to reduce the fuel consumption, environmental noise and mechanical wear of engine parts. Optimization of the controller is difficult due to the non-linearity and non-stationarity of the plant. The structure of Main Voltage Controller proposed in this paper employs one hidden layer artificial neural network to estimate the unknown plant nonlinearities on-line. ANN serves as a speed compensator and does not need a process model to predict future performance. To increase the stability and convergence of the algorithm, the Resilient backpropagation (Rprop) adaptive learning scheme has been employed. The presented solution allows maintaining suitable efficiency at steady state and adequate transient performance. The proposed neuro-control system have been widely tested in Matlab/Simulink environment. In addition experimental test has been perform in the laboratory setup where internal combustion engine was emulated by using PMSM drive. Obtained test results have been presented to show effectiveness of proposed neural control system.
{"title":"Neuro-control system for converter based electrical energy source - Test performed in laboratory setup with combustion engine emulator","authors":"J. Sobolewski, L. Grzesiak","doi":"10.1109/ICIT.2013.6505912","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505912","url":null,"abstract":"The paper investigates possible advantages from using nonlinear adaptive ANN (Artificial Neural Network)-based controller in a control system of autonomous variable speed electrical energy source with internal combustion engine. The speed is adjusted automatically as a function of load power demand. When the system is in a light or no load condition, the Main Voltage Controller automatically reduces the engine speed in order to reduce the fuel consumption, environmental noise and mechanical wear of engine parts. Optimization of the controller is difficult due to the non-linearity and non-stationarity of the plant. The structure of Main Voltage Controller proposed in this paper employs one hidden layer artificial neural network to estimate the unknown plant nonlinearities on-line. ANN serves as a speed compensator and does not need a process model to predict future performance. To increase the stability and convergence of the algorithm, the Resilient backpropagation (Rprop) adaptive learning scheme has been employed. The presented solution allows maintaining suitable efficiency at steady state and adequate transient performance. The proposed neuro-control system have been widely tested in Matlab/Simulink environment. In addition experimental test has been perform in the laboratory setup where internal combustion engine was emulated by using PMSM drive. Obtained test results have been presented to show effectiveness of proposed neural control system.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133465591","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505975
Julian A. Fernandez, Seddik Bacha, Delphine Riu, H. Turker, Marc Paupert
A method to reduce the current three phase unbalance using single phase Plug-in Hybrid Electric Vehicle (PHEV) chargers is presented in this paper. A reduction in the voltage unbalance has been achieved as a consequence of the mitigation of the current unbalance. The method performs the reactive power management on the PHEV charger in order to reduce the unbalance factor without affecting the battery charging time or charging power. The method works under restrictions to preserve the voltage quality. A simulation on Matlab-Simulink® of a three phase housing group with power profiles, initial states of charge, charging start time and PHEV category randomly selected is presented. A reduction of 50 % at some times in the day is illustrated.
{"title":"Current unbalance reduction in three-phase systems using single phase PHEV chargers","authors":"Julian A. Fernandez, Seddik Bacha, Delphine Riu, H. Turker, Marc Paupert","doi":"10.1109/ICIT.2013.6505975","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505975","url":null,"abstract":"A method to reduce the current three phase unbalance using single phase Plug-in Hybrid Electric Vehicle (PHEV) chargers is presented in this paper. A reduction in the voltage unbalance has been achieved as a consequence of the mitigation of the current unbalance. The method performs the reactive power management on the PHEV charger in order to reduce the unbalance factor without affecting the battery charging time or charging power. The method works under restrictions to preserve the voltage quality. A simulation on Matlab-Simulink® of a three phase housing group with power profiles, initial states of charge, charging start time and PHEV category randomly selected is presented. A reduction of 50 % at some times in the day is illustrated.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117262698","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505906
M. Aguirre, M. A. Engelhardt, J. Bracco, M. Valla
Multilevel converters constitute a high performance and high reliability option for industrial applications such as motor control, transmission and distribution electrical systems, and interface with alternative energy sources and non-conventional storage systems. The biggest challenge about multilevel topologies is the balance of dividing reactive components (capacitors in voltage converters, and inductors in current converters). In this paper, two methods to force current balance in a Multilevel Current Source Inverter (MCSI) are presented. Both require minimum computing power with excellent closed loop dynamic response.
{"title":"Current balance control in a multilevel current source inverter","authors":"M. Aguirre, M. A. Engelhardt, J. Bracco, M. Valla","doi":"10.1109/ICIT.2013.6505906","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505906","url":null,"abstract":"Multilevel converters constitute a high performance and high reliability option for industrial applications such as motor control, transmission and distribution electrical systems, and interface with alternative energy sources and non-conventional storage systems. The biggest challenge about multilevel topologies is the balance of dividing reactive components (capacitors in voltage converters, and inductors in current converters). In this paper, two methods to force current balance in a Multilevel Current Source Inverter (MCSI) are presented. Both require minimum computing power with excellent closed loop dynamic response.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114598761","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505754
O. Asowata, J. Swart, C. Pienaar
The purpose of this paper is to correlate the power conversion of a photovoltaic (PV) panel to the global solar irradiance obtained from a software package called Meteonorm. Power conversion time is defined as the percentage of time in which a PV panel is converting solar energy into electrical energy and was determined for a nine month period from April through December 2011. Preliminary results, which include regression analysis (R2), conversion-time per week and work-time per day, indicate a favorably comparison between the empirical results and the simulation results.
{"title":"Correlating the power conversion of a PV panel to the solar irradiance obtained from Meteonorm","authors":"O. Asowata, J. Swart, C. Pienaar","doi":"10.1109/ICIT.2013.6505754","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505754","url":null,"abstract":"The purpose of this paper is to correlate the power conversion of a photovoltaic (PV) panel to the global solar irradiance obtained from a software package called Meteonorm. Power conversion time is defined as the percentage of time in which a PV panel is converting solar energy into electrical energy and was determined for a nine month period from April through December 2011. Preliminary results, which include regression analysis (R2), conversion-time per week and work-time per day, indicate a favorably comparison between the empirical results and the simulation results.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121017961","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505883
R. Visser, J. Pretorius, L. Pretorius
Well planned research may play an integral part in the life of a mine or project and creates a practical plan of running and developing the mine. These research results for the case study company may be used as a practical strategic mine plan, in the end not only pro-long the life of the mine but achieve targeted value and tonnes for the specific plant. This research provides four different scenarios whereby there are certain constraints applied, and the outcome of the schedules used to make a calculated decision on the best way of mining a specific ore body.
{"title":"A case study in developing a life of mine plan","authors":"R. Visser, J. Pretorius, L. Pretorius","doi":"10.1109/ICIT.2013.6505883","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505883","url":null,"abstract":"Well planned research may play an integral part in the life of a mine or project and creates a practical plan of running and developing the mine. These research results for the case study company may be used as a practical strategic mine plan, in the end not only pro-long the life of the mine but achieve targeted value and tonnes for the specific plant. This research provides four different scenarios whereby there are certain constraints applied, and the outcome of the schedules used to make a calculated decision on the best way of mining a specific ore body.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"27 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116686074","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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