Pub Date : 2015-03-03DOI: 10.1109/ESARS.2015.7101459
J. Kammermann, I. Bolvashenkov, H. Herzog
Within this paper, a first approach for the selection of the appropriate machine will be presented. The constant need of electrical drive trains and therefore electrical machines requires the selection of the right electrical machine regarding the application requirements. Within this work, the different machine types are briefly opposed to each other regarding their disadvantages and advantages. Then, existent machines of those types are compared based on power density (volume, weight) and efficiency. Finally, reliability is an important factor for the selection procedure, thus it will be explained how reliability estimation can be used for multi-phases permanent magnet synchronous machines, even though there are not enough data available.
{"title":"Approach for comparative analysis of electric traction machines","authors":"J. Kammermann, I. Bolvashenkov, H. Herzog","doi":"10.1109/ESARS.2015.7101459","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101459","url":null,"abstract":"Within this paper, a first approach for the selection of the appropriate machine will be presented. The constant need of electrical drive trains and therefore electrical machines requires the selection of the right electrical machine regarding the application requirements. Within this work, the different machine types are briefly opposed to each other regarding their disadvantages and advantages. Then, existent machines of those types are compared based on power density (volume, weight) and efficiency. Finally, reliability is an important factor for the selection procedure, thus it will be explained how reliability estimation can be used for multi-phases permanent magnet synchronous machines, even though there are not enough data available.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131015457","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101438
Chamaret Andre-philippe, Frudier Didier
One of the main historic component of the electro technical domain, the electrical transformer, is close to be revolutionized thanks to high power semi-conductors for railway application : conventional traction transformer is dead ? Maybe, but first, it's important to understand how this evolution happens and why the interest is so important? What are the impacts and the benefits for traction drive chain, for the train, for railway operators? This paper will try to present the history and the major events of the traction transformer used in railway rolling stock and will show the beginning of new technology revolution for the future of our trains.
{"title":"Evolution and future of traction transformer on rolling stocks","authors":"Chamaret Andre-philippe, Frudier Didier","doi":"10.1109/ESARS.2015.7101438","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101438","url":null,"abstract":"One of the main historic component of the electro technical domain, the electrical transformer, is close to be revolutionized thanks to high power semi-conductors for railway application : conventional traction transformer is dead ? Maybe, but first, it's important to understand how this evolution happens and why the interest is so important? What are the impacts and the benefits for traction drive chain, for the train, for railway operators? This paper will try to present the history and the major events of the traction transformer used in railway rolling stock and will show the beginning of new technology revolution for the future of our trains.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132661713","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101420
F. Rivera-Calle, L. I. Minchala-Ávila, J. V. Montesdeoca-Contreras, J. A. Morales-Garcia
Early detection of faults in power lines allows improve the service quality and therefore a reduction in high operating costs that a failure of this type implies. This paper describes a method used to determine the type of failure occurs in a three-phase over time, using tools as Hilbert transform and fuzzy classifier for successful detection is done. The algorithm developed uses each of the power lines phases which are analyzed in its angle of coverage and its variation in time, after this analysis the results classified by a classifier Fuzzy c-means. This classifier makes groups of fault data and no-fault data. The results show a high performance in classified values near to zero as correct.
{"title":"Fault diagnosis in power lines using Hilbert transform and fuzzy classifier","authors":"F. Rivera-Calle, L. I. Minchala-Ávila, J. V. Montesdeoca-Contreras, J. A. Morales-Garcia","doi":"10.1109/ESARS.2015.7101420","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101420","url":null,"abstract":"Early detection of faults in power lines allows improve the service quality and therefore a reduction in high operating costs that a failure of this type implies. This paper describes a method used to determine the type of failure occurs in a three-phase over time, using tools as Hilbert transform and fuzzy classifier for successful detection is done. The algorithm developed uses each of the power lines phases which are analyzed in its angle of coverage and its variation in time, after this analysis the results classified by a classifier Fuzzy c-means. This classifier makes groups of fault data and no-fault data. The results show a high performance in classified values near to zero as correct.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132050685","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101441
Junci Cao, Weili Li, Yihuang Zhang, Xiaochen Zhang, Youming Jiang, Y. He
High-speed traction motor is the central component of the power traction system in high speed CRH train, and also the key power output device. Its reliability determines the power traction system security, and its thermal safety issue is one of the key researches, especially the working temperature rise of the stator windings and slot insulation. Based on the forced air cooling system and the multiple operating states, the fluid flowing states and heat transfer in traction motor is investigated. A 2D temperature analysis method is proposed, in which the highest temperature of insulation section determine based on the 3D fluid calculation is taken as the analysis model. This could ensure the accuracy of the insulated thermal safety assessment, and save a lot of computing time. It provides a reference method for the design and analyses on such motor.
{"title":"Analyses on heat transfer and fluid flowing in a traction motor used in high-speed CRH","authors":"Junci Cao, Weili Li, Yihuang Zhang, Xiaochen Zhang, Youming Jiang, Y. He","doi":"10.1109/ESARS.2015.7101441","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101441","url":null,"abstract":"High-speed traction motor is the central component of the power traction system in high speed CRH train, and also the key power output device. Its reliability determines the power traction system security, and its thermal safety issue is one of the key researches, especially the working temperature rise of the stator windings and slot insulation. Based on the forced air cooling system and the multiple operating states, the fluid flowing states and heat transfer in traction motor is investigated. A 2D temperature analysis method is proposed, in which the highest temperature of insulation section determine based on the 3D fluid calculation is taken as the analysis model. This could ensure the accuracy of the insulated thermal safety assessment, and save a lot of computing time. It provides a reference method for the design and analyses on such motor.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122408256","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101491
R. Manzoni
Developed since middle nineteen seventies, the Sodium Nickel Chloride Battery Technology shows solid and proven results for energy storage and clean powering of electric vehicles. The Sodium Nickel chloride Technology highlights are high specific energy at battery level, immunity to ambient temperature conditions and constant performance and cycle life in harsh operating environments, possibility of long storage without any degradation, safety, low environmental impact with fully recyclable materials. Batteries has been adopted for both pure electric or plug-in hybrid vehicles. The latest developments include a new BMS specific for automotive applications and an hybrid energy storage with batteries and supercap working in parallel.
{"title":"Sodium Nickel Chloride batteries in transportation applications","authors":"R. Manzoni","doi":"10.1109/ESARS.2015.7101491","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101491","url":null,"abstract":"Developed since middle nineteen seventies, the Sodium Nickel Chloride Battery Technology shows solid and proven results for energy storage and clean powering of electric vehicles. The Sodium Nickel chloride Technology highlights are high specific energy at battery level, immunity to ambient temperature conditions and constant performance and cycle life in harsh operating environments, possibility of long storage without any degradation, safety, low environmental impact with fully recyclable materials. Batteries has been adopted for both pure electric or plug-in hybrid vehicles. The latest developments include a new BMS specific for automotive applications and an hybrid energy storage with batteries and supercap working in parallel.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127967931","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101435
I. Szenasy, Z. Varga, Zoltán Szeli
For electric vehicles an applied control of PMSM is the flux weakening operation for extending the region over nominal speed on nominal voltage. This paper deals with these questions and its impacts. Proved methods increase the torque angle and the d axis directed component of the stator current vector reduces the main flux, but the eddy current loss developing in magnets became significant. These impacts and their reduction need several investigations. This paper preents the possibilities and limits of flux-weakening for a given PMSM, and gives a usable optimum control strategy on nominal power's region by varied speeds.
{"title":"Optimum control strategy for PMSM in field-weakening region by constant power","authors":"I. Szenasy, Z. Varga, Zoltán Szeli","doi":"10.1109/ESARS.2015.7101435","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101435","url":null,"abstract":"For electric vehicles an applied control of PMSM is the flux weakening operation for extending the region over nominal speed on nominal voltage. This paper deals with these questions and its impacts. Proved methods increase the torque angle and the d axis directed component of the stator current vector reduces the main flux, but the eddy current loss developing in magnets became significant. These impacts and their reduction need several investigations. This paper preents the possibilities and limits of flux-weakening for a given PMSM, and gives a usable optimum control strategy on nominal power's region by varied speeds.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126039681","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101469
M. Cupelli, M. Mirz, A. Monti
In future all-electrical ships with Medium Voltage DC distribution, the power system stability can be jeopardized by the presence of constant power loads, due to the negative impedance characteristic of their tightly regulated converters. In order to solve this problem we apply backstepping as a nonlinear control technique to the converter interfacing the generation side and which supplies the bus. In this work we demonstrate two versions of backstepping, which are compared to a centralized linearizing state feedback controller taken from literature.
{"title":"Application of backstepping to MVDC ship power systems with constant power loads","authors":"M. Cupelli, M. Mirz, A. Monti","doi":"10.1109/ESARS.2015.7101469","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101469","url":null,"abstract":"In future all-electrical ships with Medium Voltage DC distribution, the power system stability can be jeopardized by the presence of constant power loads, due to the negative impedance characteristic of their tightly regulated converters. In order to solve this problem we apply backstepping as a nonlinear control technique to the converter interfacing the generation side and which supplies the bus. In this work we demonstrate two versions of backstepping, which are compared to a centralized linearizing state feedback controller taken from literature.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115431162","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101432
S. Manabe, T. Ogawa, Yoichi Imamura, Shingo Minobe, J. Kawamura, Masahisa Kageyama
A simulator with high precision for calculating energy consumption in train operation has been developed by authors. In order to improve the accuracy of the simulator, it is important to input running resistance with high precision under various conditions to the simulator as parameters. Therefore, this paper proposes a method of calculating running resistance under various conditions without the running tests by using monitoring data on service trains, the track and structure database and the weather database. In addition, this paper reports the case in which the precision of the simulation results is improved by using the running resistance formula by this method.
{"title":"A method of calculating running resistance using monitoring devices for energy simulators","authors":"S. Manabe, T. Ogawa, Yoichi Imamura, Shingo Minobe, J. Kawamura, Masahisa Kageyama","doi":"10.1109/ESARS.2015.7101432","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101432","url":null,"abstract":"A simulator with high precision for calculating energy consumption in train operation has been developed by authors. In order to improve the accuracy of the simulator, it is important to input running resistance with high precision under various conditions to the simulator as parameters. Therefore, this paper proposes a method of calculating running resistance under various conditions without the running tests by using monitoring data on service trains, the track and structure database and the weather database. In addition, this paper reports the case in which the precision of the simulation results is improved by using the running resistance formula by this method.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128698236","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101492
A. Quadrelli, G. Gigliucci, E. Pasca, Stefano Farnesi, Rino Gambuti, F. Flamingo, G. Bosia
Power Conditioning Systems (PCSs), also known as Active Filters or Custom Power, are innovative devices based on Power Electronics widely used on Medium Voltage (MV) and Low Voltage (LV) power transmission networks to improve the quality of power distribution and compensate local disturbances. Some of common features are improving the quality of the power supply of particularly sensitive loads to network disturbances, such voltage sag compensation or short interruptions, peak shaving, active power factor correction. Such type of devices, especially with the primary function of peak-shaving, are very suitable coupled with Electric Vehicle Quick Charging Stations (EVQCS) due the considerable power absorbed by them from the three-phase network (in our case 400 V-50 Hz) especially at the beginning of the charging (several kW for some minutes). In this way, the network will be relieved of high power peaks need that would cause an impact on utilities and necessary investments by the distributor. This paper describes an innovative power conditioning system with energetic storage based on Lithium-Ion Ultracapacitors which have high performance in terms of specific energy and long service life. The device is designed and built to be a support for an EVQCS. The prototype is actually installed in the experimental area of Enel Ingegneria e Ricerca, located in Livorno, where a series of tests has proven its functionality and benifts for the grid. Future tests will be dedicated on interaction with a Li-ion storage system to improve energy services.
电力调节系统(PCSs)，也称为有源滤波器或定制电源，是基于电力电子技术的创新设备，广泛应用于中压(MV)和低压(LV)输电网络，以提高配电质量和补偿局部干扰。一些共同的特点是提高对网络干扰特别敏感的负载的供电质量，如电压凹陷补偿或短时中断、调峰、有源功率因数校正。这种类型的设备，特别是具有调峰主要功能的设备，非常适合与电动汽车快速充电站(EVQCS)结合使用，因为它们从三相网络(在我们的案例中为400 V-50 Hz)吸收了相当大的功率，特别是在充电开始时(几分钟几千瓦)。通过这种方式，电网将摆脱对公用事业和分销商必要投资造成影响的高功率峰值需求。本文介绍了一种基于锂离子超级电容器的新型能量存储电力调节系统，该系统具有比能量高、使用寿命长的特点。该设备的设计和制造是为了支持EVQCS。该原型实际上安装在位于利沃诺的Enel Ingegneria e Ricerca实验区，在那里进行了一系列测试，证明了它的功能和对电网的好处。未来的测试将致力于与锂离子存储系统的相互作用，以改善能源服务。
{"title":"Power quality conditioning system based on Lithium-Ion Ultracapacitors for Electric Vehicles Quick Charging Stations","authors":"A. Quadrelli, G. Gigliucci, E. Pasca, Stefano Farnesi, Rino Gambuti, F. Flamingo, G. Bosia","doi":"10.1109/ESARS.2015.7101492","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101492","url":null,"abstract":"Power Conditioning Systems (PCSs), also known as Active Filters or Custom Power, are innovative devices based on Power Electronics widely used on Medium Voltage (MV) and Low Voltage (LV) power transmission networks to improve the quality of power distribution and compensate local disturbances. Some of common features are improving the quality of the power supply of particularly sensitive loads to network disturbances, such voltage sag compensation or short interruptions, peak shaving, active power factor correction. Such type of devices, especially with the primary function of peak-shaving, are very suitable coupled with Electric Vehicle Quick Charging Stations (EVQCS) due the considerable power absorbed by them from the three-phase network (in our case 400 V-50 Hz) especially at the beginning of the charging (several kW for some minutes). In this way, the network will be relieved of high power peaks need that would cause an impact on utilities and necessary investments by the distributor. This paper describes an innovative power conditioning system with energetic storage based on Lithium-Ion Ultracapacitors which have high performance in terms of specific energy and long service life. The device is designed and built to be a support for an EVQCS. The prototype is actually installed in the experimental area of Enel Ingegneria e Ricerca, located in Livorno, where a series of tests has proven its functionality and benifts for the grid. Future tests will be dedicated on interaction with a Li-ion storage system to improve energy services.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130970783","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 : 2015-03-03DOI: 10.1109/ESARS.2015.7101479
S. Bozhko, S. Dymko, S. Kovbasa, S. Peresada
The paper deals with the development of novel vector control algorithms for traction induction motors drives. A direct field-oriented torque (speed) controller was designed using output-feedback linearizing technique. Controller guarantees asymptotic torque (speed) tracking and maximizes a torque per Ampere ratio in steady state. Nonlinear flux observer and torque-current maximization criterion take into consideration the effect of magnetic saturation hence improving the torque-flux tracking accuracy. The main advantage of the proposed controller is it's physics-based cascaded structure and simplicity of practical implementation. The experimental results confirm the developed theory as well as demonstrate the effectiveness of the proposed approach.
{"title":"MTA control for traction IM drives: Theory and experimental results","authors":"S. Bozhko, S. Dymko, S. Kovbasa, S. Peresada","doi":"10.1109/ESARS.2015.7101479","DOIUrl":"https://doi.org/10.1109/ESARS.2015.7101479","url":null,"abstract":"The paper deals with the development of novel vector control algorithms for traction induction motors drives. A direct field-oriented torque (speed) controller was designed using output-feedback linearizing technique. Controller guarantees asymptotic torque (speed) tracking and maximizes a torque per Ampere ratio in steady state. Nonlinear flux observer and torque-current maximization criterion take into consideration the effect of magnetic saturation hence improving the torque-flux tracking accuracy. The main advantage of the proposed controller is it's physics-based cascaded structure and simplicity of practical implementation. The experimental results confirm the developed theory as well as demonstrate the effectiveness of the proposed approach.","PeriodicalId":287492,"journal":{"name":"2015 International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles (ESARS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129611278","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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