Pub Date : 2013-06-16DOI: 10.1109/ITEC.2013.6573511
T. Stamati, P. Bauer
Contactless Power Transfer (CPT) systems are applicable for charging electric vehicles (EVs) without any physical interconnection. These systems can be installed on roadways in order to charge the vehicles while driving. The implementation of such on-road charging systems in order to extend the driving range and decrease the EV battery size is investigated in this paper. The percentage of road that should be covered and the power transfer capability of the system are estimated. Some design considerations, such as the distribution and the length of the CPT segments over the road, are explained. Finally, the total power demand for all the passing-by vehicles using the system is calculated and the possibility of powering the EVs directly from renewable energy sources is discussed.
{"title":"On-road charging of electric vehicles","authors":"T. Stamati, P. Bauer","doi":"10.1109/ITEC.2013.6573511","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573511","url":null,"abstract":"Contactless Power Transfer (CPT) systems are applicable for charging electric vehicles (EVs) without any physical interconnection. These systems can be installed on roadways in order to charge the vehicles while driving. The implementation of such on-road charging systems in order to extend the driving range and decrease the EV battery size is investigated in this paper. The percentage of road that should be covered and the power transfer capability of the system are estimated. Some design considerations, such as the distribution and the length of the CPT segments over the road, are explained. Finally, the total power demand for all the passing-by vehicles using the system is calculated and the possibility of powering the EVs directly from renewable energy sources is discussed.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122491596","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573478
V. Prasanth, P. Bauer
A major problem concerning On Road Charging of Electric Vehicles via Inductive Power Transfer (IPT) links is the large variation in power transfer and efficiency due to displacement of the secondary from the primary. This paper looks into this problem referred to as misalignment, both laterally and longitudinally. For lateral misalignment, experimental results were obtained by considering horizontal and vertical coils separately. The technique of combining the quadrature coils to form the quadrature pickup so as to obtain a flatter mutual inductance profile is suggested by directly combining the individual secondary coils. Longitudinal misalignment is particularly of interest when sectional primaries are to be constructed. In case of longitudinal misalignment, unsymmetrical mutual inductance profile at the extremes of the primary was observed experimentally. The concept of “Edge Effect” was introduced to explain the same. A solution to this problem is suggested and the concept of Best Efficiency Point (BEP) introduced. Theoretical efficiencies were obtained to select the best configuration of the primary for power transfer.
{"title":"Study of misalignment for On Road Charging","authors":"V. Prasanth, P. Bauer","doi":"10.1109/ITEC.2013.6573478","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573478","url":null,"abstract":"A major problem concerning On Road Charging of Electric Vehicles via Inductive Power Transfer (IPT) links is the large variation in power transfer and efficiency due to displacement of the secondary from the primary. This paper looks into this problem referred to as misalignment, both laterally and longitudinally. For lateral misalignment, experimental results were obtained by considering horizontal and vertical coils separately. The technique of combining the quadrature coils to form the quadrature pickup so as to obtain a flatter mutual inductance profile is suggested by directly combining the individual secondary coils. Longitudinal misalignment is particularly of interest when sectional primaries are to be constructed. In case of longitudinal misalignment, unsymmetrical mutual inductance profile at the extremes of the primary was observed experimentally. The concept of “Edge Effect” was introduced to explain the same. A solution to this problem is suggested and the concept of Best Efficiency Point (BEP) introduced. Theoretical efficiencies were obtained to select the best configuration of the primary for power transfer.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132643449","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573506
M. A. Cortés Guzmán, J. E. Ramirez Parra, J. Rosero
This article presents a methodology for efficiency and performance evaluation in electric vehicles (EVs) in different segments (cars, motorbikes, bicycles and vehicles for massive transportation), that allows to characterize its real behavior in Bogotá, where the performance is affected by local conditions, such as weather, geography, driving and culture. The methodology includes a procedure which covers instruments' specification according to standards, criteria and selection of road test, and information analysis by calculating various indicators.
{"title":"Methodology for efficiency and performance evaluation in electric vehicles (EVs) in Bogotá D.C.","authors":"M. A. Cortés Guzmán, J. E. Ramirez Parra, J. Rosero","doi":"10.1109/ITEC.2013.6573506","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573506","url":null,"abstract":"This article presents a methodology for efficiency and performance evaluation in electric vehicles (EVs) in different segments (cars, motorbikes, bicycles and vehicles for massive transportation), that allows to characterize its real behavior in Bogotá, where the performance is affected by local conditions, such as weather, geography, driving and culture. The methodology includes a procedure which covers instruments' specification according to standards, criteria and selection of road test, and information analysis by calculating various indicators.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"803 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134063066","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6574526
Dingguo Lu, W. Qiao
Condition monitoring and fault diagnosis (CMFD) of drivetrain gearboxes has become a prominent challenge in assorted industries. Current-based diagnostic techniques have significant advantages over traditional vibration-based techniques in terms of accessibility, cost, implementation and reliability. This paper proposes a current-based, frequency demodulation-aided CMFD method for drivetrain gearboxes. A mathematical model is developed for a drivetrain consisting of a two-stage gearbox and a permanent magnet synchronous generator (PMSG), from which the characteristic frequencies of gearbox faults in the PMSG stator current are derived. An adaptive signal resampling method is proposed to convert the variable fault characteristic frequencies to constant values for the drivetrain running at variable speed conditions. A demodulation method, combining the Hilbert transform, a finite impulse response (FIR) differentiator, and a phase unwrapping algorithm, is developed to extract the instantaneous frequency (IF) patterns that are related to the fault-induced gearbox vibration. A fault detector is proposed for diagnosis of gearbox faults using statistical analysis on the extracted fault signatures. Experimental studies are carried out to validate the effectiveness of the proposed method.
{"title":"Frequency demodulation-aided condition monitoring for drivetrain gearboxes","authors":"Dingguo Lu, W. Qiao","doi":"10.1109/ITEC.2013.6574526","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6574526","url":null,"abstract":"Condition monitoring and fault diagnosis (CMFD) of drivetrain gearboxes has become a prominent challenge in assorted industries. Current-based diagnostic techniques have significant advantages over traditional vibration-based techniques in terms of accessibility, cost, implementation and reliability. This paper proposes a current-based, frequency demodulation-aided CMFD method for drivetrain gearboxes. A mathematical model is developed for a drivetrain consisting of a two-stage gearbox and a permanent magnet synchronous generator (PMSG), from which the characteristic frequencies of gearbox faults in the PMSG stator current are derived. An adaptive signal resampling method is proposed to convert the variable fault characteristic frequencies to constant values for the drivetrain running at variable speed conditions. A demodulation method, combining the Hilbert transform, a finite impulse response (FIR) differentiator, and a phase unwrapping algorithm, is developed to extract the instantaneous frequency (IF) patterns that are related to the fault-induced gearbox vibration. A fault detector is proposed for diagnosis of gearbox faults using statistical analysis on the extracted fault signatures. Experimental studies are carried out to validate the effectiveness of the proposed method.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134097541","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6574493
Seyoung Kim, S. Williamson
In this paper, a new multiple-input DC/DC integrated converter is proposed for a fuel cell/battery/ultracapacitor electric vehicle. The power density increases in the order of fuel cell, battery, and ultracapacitor and the energy density is reverse of the order. The proposed converter combines interleaved type boost converters and two parallel-connected bidirectional DC/DC converters. The advantages of the proposed converter topology are improved power density, due to the fact that a heavy power transformer is not used, and the state of charge of battery as well as that of the ultracapacitor can be controlled easily.
{"title":"Multiple input integrated DC/DC converters and supervisery control for fuel cell/battery/ultracapacitor electric vehicle","authors":"Seyoung Kim, S. Williamson","doi":"10.1109/ITEC.2013.6574493","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6574493","url":null,"abstract":"In this paper, a new multiple-input DC/DC integrated converter is proposed for a fuel cell/battery/ultracapacitor electric vehicle. The power density increases in the order of fuel cell, battery, and ultracapacitor and the energy density is reverse of the order. The proposed converter combines interleaved type boost converters and two parallel-connected bidirectional DC/DC converters. The advantages of the proposed converter topology are improved power density, due to the fact that a heavy power transformer is not used, and the state of charge of battery as well as that of the ultracapacitor can be controlled easily.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131603583","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6574501
Yue Cao, P. Krein
This paper presents averaging-based models of hybrid electric power systems for refrigeration units in delivery trucks. The model is intended to be used for a system-level power and energy flow study and eventually for a development of prototypes. Challenges unique to this hybrid application, including the thermal system interface, drive cycle response, and battery management, are introduced. The system topology is presented, including the hybrid power architecture, electrical-thermal system specifications, and the integrated model operation and controls. The modeling approach for each electrical component, including ac machines, the battery set, and converters, is discussed. An average modeling technique is used, because it can track system-level power and efficiency over a long time interval with fast simulation. Battery simulation is improved from previous literature to provide a more accurate and robust solution. The model, interfaced with the thermal system, is verified by simulation studies in MATLAB/Simulink. The average model is also validated through experiments, including an active front end test, a battery test, and a variable speed ac motor drive test. Using the model, energy and cost-effectiveness is analyzed and discussed.
{"title":"An average modeling approach for mobile refrigeration hybrid power systems with improved battery simulation","authors":"Yue Cao, P. Krein","doi":"10.1109/ITEC.2013.6574501","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6574501","url":null,"abstract":"This paper presents averaging-based models of hybrid electric power systems for refrigeration units in delivery trucks. The model is intended to be used for a system-level power and energy flow study and eventually for a development of prototypes. Challenges unique to this hybrid application, including the thermal system interface, drive cycle response, and battery management, are introduced. The system topology is presented, including the hybrid power architecture, electrical-thermal system specifications, and the integrated model operation and controls. The modeling approach for each electrical component, including ac machines, the battery set, and converters, is discussed. An average modeling technique is used, because it can track system-level power and efficiency over a long time interval with fast simulation. Battery simulation is improved from previous literature to provide a more accurate and robust solution. The model, interfaced with the thermal system, is verified by simulation studies in MATLAB/Simulink. The average model is also validated through experiments, including an active front end test, a battery test, and a variable speed ac motor drive test. Using the model, energy and cost-effectiveness is analyzed and discussed.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133253743","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6574511
Di Han, Jukkrit Noppakunkajorn, B. Sarlioglu
With the advancement of technology on wide bandgap materials such as silicon-carbide (SiC), there are now better choices of SiC power devices available than ever before. It is widely known that SiC-based switching devices provide significant performance improvements on many aspects including lower power dissipation, higher operating temperatures, and faster switching frequencies compared to conventional Si devices. However, the tremendous benefits of SiC devices have not yet been fully explored by researchers. In this paper, a popular topology of bidirectional DC-DC converter that is suitable for hybrid vehicle or electric vehicle applications is considered. Comparative analyses regarding the power loss reductions of power devices and efficiency improvements are carried out for the converter based on three sets of device combinations, e.g. all-silicon (conventional silicon IGBTs and diodes), hybrid (silicon IGBTs with SiC Schottky diodes), and all-SiC (SiC MOSFETs with SiC Schottky diodes).
{"title":"Efficiency comparison of SiC and Si-based bidirectional DC-DC converters","authors":"Di Han, Jukkrit Noppakunkajorn, B. Sarlioglu","doi":"10.1109/ITEC.2013.6574511","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6574511","url":null,"abstract":"With the advancement of technology on wide bandgap materials such as silicon-carbide (SiC), there are now better choices of SiC power devices available than ever before. It is widely known that SiC-based switching devices provide significant performance improvements on many aspects including lower power dissipation, higher operating temperatures, and faster switching frequencies compared to conventional Si devices. However, the tremendous benefits of SiC devices have not yet been fully explored by researchers. In this paper, a popular topology of bidirectional DC-DC converter that is suitable for hybrid vehicle or electric vehicle applications is considered. Comparative analyses regarding the power loss reductions of power devices and efficiency improvements are carried out for the converter based on three sets of device combinations, e.g. all-silicon (conventional silicon IGBTs and diodes), hybrid (silicon IGBTs with SiC Schottky diodes), and all-SiC (SiC MOSFETs with SiC Schottky diodes).","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"09 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114824244","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573469
F. Musavi, D. Gautam, W. Eberle, W. Dunford
In this paper, a novel, simple and accurate method is proposed to predict the RMS and average current for each component in the most common continuous conduction mode (CCM) AC-DC power factor correction (PFC) boost derived topologies. The model is based on using the effective duty cycle independent of the switching action. The proposed model enables simple and accurate estimation of powertrain component conduction losses. The paper includes the derivation of the RMS, or average current for the boost and interleaved boost PFC topologies. PSIM simulation and experimental results are used to verify the accuracy of model. Experimental and simulation results of a prototype interleaved boost converter converting universal AC input voltage to 400 V DC at up to 3.4 kW output are given to verify the proposed model. The experimental results demonstrate that the model can correctly predict the RMS and average currents in the interleaved boost topology.
{"title":"A simplified power loss calculation method for PFC boost topologies","authors":"F. Musavi, D. Gautam, W. Eberle, W. Dunford","doi":"10.1109/ITEC.2013.6573469","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573469","url":null,"abstract":"In this paper, a novel, simple and accurate method is proposed to predict the RMS and average current for each component in the most common continuous conduction mode (CCM) AC-DC power factor correction (PFC) boost derived topologies. The model is based on using the effective duty cycle independent of the switching action. The proposed model enables simple and accurate estimation of powertrain component conduction losses. The paper includes the derivation of the RMS, or average current for the boost and interleaved boost PFC topologies. PSIM simulation and experimental results are used to verify the accuracy of model. Experimental and simulation results of a prototype interleaved boost converter converting universal AC input voltage to 400 V DC at up to 3.4 kW output are given to verify the proposed model. The experimental results demonstrate that the model can correctly predict the RMS and average currents in the interleaved boost topology.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123995422","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6574497
N. Wong, K. Zhuge, Mehrdad Kazerani
On-board battery charger is an essential component of a plugin vehicle. Bidirectionality, even though not realized yet in charging systems of commercial plugin vehicles, is being seriously considered for future developments, due to provision of V2G capabilities. This paper first presents the structure of a high performance two-stage, level-2 on-board bidirectional battery charger, as the interface between the utility grid and the plugin vehicle's battery pack. Then, a comparative evaluation of three control schemes based on PI controller, synchronous DQ-frame model and PR controller, for grid-side AC-DC converter is performed. Simulation results are used to support the analytical expectations.
{"title":"A comparative evaluation of control techniques for grid-side AC-DC converter in a two-stage level-two bidirectional battery charger","authors":"N. Wong, K. Zhuge, Mehrdad Kazerani","doi":"10.1109/ITEC.2013.6574497","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6574497","url":null,"abstract":"On-board battery charger is an essential component of a plugin vehicle. Bidirectionality, even though not realized yet in charging systems of commercial plugin vehicles, is being seriously considered for future developments, due to provision of V2G capabilities. This paper first presents the structure of a high performance two-stage, level-2 on-board bidirectional battery charger, as the interface between the utility grid and the plugin vehicle's battery pack. Then, a comparative evaluation of three control schemes based on PI controller, synchronous DQ-frame model and PR controller, for grid-side AC-DC converter is performed. Simulation results are used to support the analytical expectations.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"18 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122598581","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573502
L. Lai, M. Ehsani
The HEV drive train with a full size engine can guarantee vehicle performance at least as good as the conventional vehicle, and with an electrical drive in parallel it will improve the fuel economy and performance beyond the conventional car, but with minimal cost increase. By analyzing the HEV fuel economy versus the increasing of the electrical drive power on typical driving conditions, the optimal hybridization electric power capacity is determined. Thus, the full size engine HEV shows significant improvement in fuel economy and performance, with relatively short cost recovery period.
{"title":"Design study of parallel HEV drive train with full size engine","authors":"L. Lai, M. Ehsani","doi":"10.1109/ITEC.2013.6573502","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573502","url":null,"abstract":"The HEV drive train with a full size engine can guarantee vehicle performance at least as good as the conventional vehicle, and with an electrical drive in parallel it will improve the fuel economy and performance beyond the conventional car, but with minimal cost increase. By analyzing the HEV fuel economy versus the increasing of the electrical drive power on typical driving conditions, the optimal hybridization electric power capacity is determined. Thus, the full size engine HEV shows significant improvement in fuel economy and performance, with relatively short cost recovery period.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129562255","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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