Pub Date : 2020-01-01DOI: 10.1504/ijehv.2020.104271
Travis E. McWhirter, T. Wagner, J. Stubbs, Denise M. Rizzo, Jada B. Williams
A hybrid electric tracked ground vehicle (HETGV) can reduce military fuel usage, however a review of current tools determined they are not suitable to estimate HEGTV performance. Based on topographic data and vehicle attributes, this research developed an estimation tool by creating a model to determine tracked vehicle energy and fuel requirements, and using these requirements, created a HEGTV cost and performance optimisation for the Bradley fighting vehicle energy system. The optimised design reduced fuel consumption by 15%, and met the vehicle's peak power requirement of 365 kW, with a recommended configuration of a 135 kW generator and 100 kWh battery, and an estimated drivetrain and fuel cost of $155,000. This analysis concludes by articulating the operational and tactical impacts of increased fuel efficiency.
{"title":"Tracked vehicle physics-based energy modelling and series hybrid system optimisation for the Bradley fighting vehicle","authors":"Travis E. McWhirter, T. Wagner, J. Stubbs, Denise M. Rizzo, Jada B. Williams","doi":"10.1504/ijehv.2020.104271","DOIUrl":"https://doi.org/10.1504/ijehv.2020.104271","url":null,"abstract":"A hybrid electric tracked ground vehicle (HETGV) can reduce military fuel usage, however a review of current tools determined they are not suitable to estimate HEGTV performance. Based on topographic data and vehicle attributes, this research developed an estimation tool by creating a model to determine tracked vehicle energy and fuel requirements, and using these requirements, created a HEGTV cost and performance optimisation for the Bradley fighting vehicle energy system. The optimised design reduced fuel consumption by 15%, and met the vehicle's peak power requirement of 365 kW, with a recommended configuration of a 135 kW generator and 100 kWh battery, and an estimated drivetrain and fuel cost of $155,000. This analysis concludes by articulating the operational and tactical impacts of increased fuel efficiency.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":"1 1","pages":"1"},"PeriodicalIF":0.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1504/ijehv.2020.104271","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66764897","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 : 2019-09-27DOI: 10.1504/ijehv.2019.10024318
R. Sabzehgar, Y. M. Roshan
In this paper, we propose a sliding-mode control (SMC) strategy for bidirectional operation of a three-phase pulse width modulation (PWM) converter suitable for plug-in electric vehicles (PEVs). The proposed controller operates the three-phase converter at unity power factor with no steady-state errors. The controller takes advantage of inherent characteristics of sliding-mode controllers such as fast dynamics, low harmonics, and being independent of the load and system parameters. The proposed control strategy keeps the input voltage and current in phase in charging mode, when the converter acts as a rectifier and boost converter. Similarly, controller maintains the input voltage and current of the three-phase system out of phase in discharging mode, when the converter is operated as an inverter. Numerical studies are conducted to evaluate the performance of the proposed controller.
{"title":"Nonlinear sliding-mode control of a bidirectional three-phase converter for plug-in electric vehicles","authors":"R. Sabzehgar, Y. M. Roshan","doi":"10.1504/ijehv.2019.10024318","DOIUrl":"https://doi.org/10.1504/ijehv.2019.10024318","url":null,"abstract":"In this paper, we propose a sliding-mode control (SMC) strategy for bidirectional operation of a three-phase pulse width modulation (PWM) converter suitable for plug-in electric vehicles (PEVs). The proposed controller operates the three-phase converter at unity power factor with no steady-state errors. The controller takes advantage of inherent characteristics of sliding-mode controllers such as fast dynamics, low harmonics, and being independent of the load and system parameters. The proposed control strategy keeps the input voltage and current in phase in charging mode, when the converter acts as a rectifier and boost converter. Similarly, controller maintains the input voltage and current of the three-phase system out of phase in discharging mode, when the converter is operated as an inverter. Numerical studies are conducted to evaluate the performance of the proposed controller.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46622250","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 : 2019-09-27DOI: 10.1504/ijehv.2019.10024316
Y. R. Tagore, Anuradha Kotapati, Rajani Kandipati
This paper presents the analysis and design of a quadratic buck converter for electric vehicle applications where large voltage conversion ratios are required i.e., 48V/12 V at 50 kHz. The converter performance is analysed with digital-average current mode and the sliding mode current control strategies. In sliding-mode current control, the sliding parameters are finely tuned to achieve robustness against parameter variations. The simulation results of the above mentioned control strategies are compared for both line as well as load regulations. The efficiency analysis of the converter is also presented at different input and load conditions.
{"title":"Performance analysis of quadratic buck converter for electric vehicle battery charging applications","authors":"Y. R. Tagore, Anuradha Kotapati, Rajani Kandipati","doi":"10.1504/ijehv.2019.10024316","DOIUrl":"https://doi.org/10.1504/ijehv.2019.10024316","url":null,"abstract":"This paper presents the analysis and design of a quadratic buck converter for electric vehicle applications where large voltage conversion ratios are required i.e., 48V/12 V at 50 kHz. The converter performance is analysed with digital-average current mode and the sliding mode current control strategies. In sliding-mode current control, the sliding parameters are finely tuned to achieve robustness against parameter variations. The simulation results of the above mentioned control strategies are compared for both line as well as load regulations. The efficiency analysis of the converter is also presented at different input and load conditions.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41766941","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 : 2019-09-27DOI: 10.1504/ijehv.2019.10024313
Adnane Houbbadi, R. Trigui, S. Pélissier, E. Redondo-Iglesias, Tanguy Bouton
The use of electric buses (EBs) is expected to increase significantly in the coming years. Uncontrolled charging of EBs can affect not only the power grid (grid instability, harmonic pollution) but also the operating cost. This paper introduces an optimal charging strategy based on charging schedule planning and modulation of charging power for a fleet of electrical-powered buses. The optimal charging strategy allows minimising the charging cost as well as the load power variations using quadratic programming. The proposed quadratic programming can significantly reduce the computation time and simultaneously handle a large bus fleet. First results indicate a significant reduction in customer energy bills while avoiding potential penalties due to peak loads.
{"title":"A quadratic programming based optimisation to manage electric bus fleet charging","authors":"Adnane Houbbadi, R. Trigui, S. Pélissier, E. Redondo-Iglesias, Tanguy Bouton","doi":"10.1504/ijehv.2019.10024313","DOIUrl":"https://doi.org/10.1504/ijehv.2019.10024313","url":null,"abstract":"The use of electric buses (EBs) is expected to increase significantly in the coming years. Uncontrolled charging of EBs can affect not only the power grid (grid instability, harmonic pollution) but also the operating cost. This paper introduces an optimal charging strategy based on charging schedule planning and modulation of charging power for a fleet of electrical-powered buses. The optimal charging strategy allows minimising the charging cost as well as the load power variations using quadratic programming. The proposed quadratic programming can significantly reduce the computation time and simultaneously handle a large bus fleet. First results indicate a significant reduction in customer energy bills while avoiding potential penalties due to peak loads.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42911325","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 : 2019-09-27DOI: 10.1504/ijehv.2019.10024319
Hongyu Shu, Cheng Guo, Yitong Song, Xianbao Chen, S. Luo
Considering some technical and economic reasons, it is not easy to directly measure the time-varying states which have a great impact on speed regulation performance in permanent magnet synchronous motor (PMSM) drive system. This paper proposes a method to estimate rotor speed, rotor position and load torque disturbance by utilising real-time estimations, based on the extended Kalman filter (EKF). In order to guarantee the accuracy and stability of PMSM drive system while running under load torque disturbance, this paper proposes a cascade closed-loop control strategy as a solution. The entire system is designed to track reference speed trajectory based on the estimated rotor speed, rotor position and load torque, using the model predictive control (MPC) algorithm based on linear PMSM model. Simulation results demonstrate the effectiveness of the states observer, and the cascade MPC structure shows the good performance in speed tracking of PMSM drive system.
{"title":"Design of model predictive controllers for PMSM drive system based on the extended Kalman filter observer","authors":"Hongyu Shu, Cheng Guo, Yitong Song, Xianbao Chen, S. Luo","doi":"10.1504/ijehv.2019.10024319","DOIUrl":"https://doi.org/10.1504/ijehv.2019.10024319","url":null,"abstract":"Considering some technical and economic reasons, it is not easy to directly measure the time-varying states which have a great impact on speed regulation performance in permanent magnet synchronous motor (PMSM) drive system. This paper proposes a method to estimate rotor speed, rotor position and load torque disturbance by utilising real-time estimations, based on the extended Kalman filter (EKF). In order to guarantee the accuracy and stability of PMSM drive system while running under load torque disturbance, this paper proposes a cascade closed-loop control strategy as a solution. The entire system is designed to track reference speed trajectory based on the estimated rotor speed, rotor position and load torque, using the model predictive control (MPC) algorithm based on linear PMSM model. Simulation results demonstrate the effectiveness of the states observer, and the cascade MPC structure shows the good performance in speed tracking of PMSM drive system.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46185653","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 : 2019-09-27DOI: 10.1504/ijehv.2019.10024315
K. P. Divakarla, A. Emadi, S. Razavi, S. Habibi, Fengjun Yan
The automotive industry is seen to be making a monumental paradigm shift from manual to semi-autonomous to fully autonomous vehicles. As such, this paper attempts to offer an overview of some of the major aspects associated with an autonomous vehicle. The demand for autonomous vehicles has grown tremendously with the increasing number of road accidents caused due to driver distraction. Based on the level of autonomy within vehicles, it is possible to either have autonomous systems that will just assist the driver for safe operation of the vehicle or could take over the complete control of the vehicle. Autonomous vehicles seem to have numerous advantages for road safety, traffic optimisation, military or medical applications where only minimal human intervention is desirable and so on. This paper attempts to highlight the vast majority of vital and most relevant topics emerging in the field of autonomous vehicle technology.
{"title":"A review of autonomous vehicle technology landscape","authors":"K. P. Divakarla, A. Emadi, S. Razavi, S. Habibi, Fengjun Yan","doi":"10.1504/ijehv.2019.10024315","DOIUrl":"https://doi.org/10.1504/ijehv.2019.10024315","url":null,"abstract":"The automotive industry is seen to be making a monumental paradigm shift from manual to semi-autonomous to fully autonomous vehicles. As such, this paper attempts to offer an overview of some of the major aspects associated with an autonomous vehicle. The demand for autonomous vehicles has grown tremendously with the increasing number of road accidents caused due to driver distraction. Based on the level of autonomy within vehicles, it is possible to either have autonomous systems that will just assist the driver for safe operation of the vehicle or could take over the complete control of the vehicle. Autonomous vehicles seem to have numerous advantages for road safety, traffic optimisation, military or medical applications where only minimal human intervention is desirable and so on. This paper attempts to highlight the vast majority of vital and most relevant topics emerging in the field of autonomous vehicle technology.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43136634","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}
To improve the working reliability and service life of the outer-rotor in-wheel motor of the electric vehicle, and based on the electric vehicle parameters and motion equations, the rated torque, rated efficiency and other performance parameters are determined. The internal dimensions of the in-wheel motor are designed according to the parameters of electric vehicle, including stator winding, air gap and permanent magnet, which are used to calculate the electromagnetic circuit and the electromagnetic parameters. The model of the in-wheel motor is established by Ansoft Maxwell software and the designed motor is analysed by the finite element analysis method. The magnetic field inside the in-wheel motor at different timings is analysed. The conformity of the simulation results and the design calculation results indicate that this method can be used to provide a theoretical basis to make further optimal design of the outer-rotor in-wheel motor driving system.
{"title":"Design and analysis of outer-rotor in-wheel motor driving system of electric vehicle","authors":"Qiping Chen, Q. Xiao, Changping Qiu, Sheng Kang, Huang Juanlin, Conghui Zhou","doi":"10.1504/ijehv.2019.10024314","DOIUrl":"https://doi.org/10.1504/ijehv.2019.10024314","url":null,"abstract":"To improve the working reliability and service life of the outer-rotor in-wheel motor of the electric vehicle, and based on the electric vehicle parameters and motion equations, the rated torque, rated efficiency and other performance parameters are determined. The internal dimensions of the in-wheel motor are designed according to the parameters of electric vehicle, including stator winding, air gap and permanent magnet, which are used to calculate the electromagnetic circuit and the electromagnetic parameters. The model of the in-wheel motor is established by Ansoft Maxwell software and the designed motor is analysed by the finite element analysis method. The magnetic field inside the in-wheel motor at different timings is analysed. The conformity of the simulation results and the design calculation results indicate that this method can be used to provide a theoretical basis to make further optimal design of the outer-rotor in-wheel motor driving system.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46770748","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 : 2019-07-26DOI: 10.1504/IJEHV.2019.101299
Chao Ma, Yang Kun, Lidong Miao, Meiqi Chen, Song Gao
In this study, driving condition classification and recognition based adaptive optimal control strategy is developed for new type four wheel drive plug-in hybrid electric vehicle (PHEV). First, power characteristics of the proposed PHEV are analysed. The basic rule based and adaptive optimal control strategies are developed. According to the support vector machine (SVM) based classification theory, the RBF neural network kernel function is introduced and the multi classification SVM with the one-against-one method is selected. The feature parameters are then determined and extracted using real road experiment data. It is seen from the classification results that RBF kernel function based SVM has relatively high accuracy of 93.2%. Based on the developed energy management strategy library and driving cost theory, adaptive optimal control strategy is developed using Matlab/Simulink. It is found from the simulation results that the adaptive optimal control achieves the efficiency increase of 13.4%, which implies validity of the proposed adaptive optimal control strategy.
{"title":"Development of driving condition classification based adaptive optimal control strategy for PHEV","authors":"Chao Ma, Yang Kun, Lidong Miao, Meiqi Chen, Song Gao","doi":"10.1504/IJEHV.2019.101299","DOIUrl":"https://doi.org/10.1504/IJEHV.2019.101299","url":null,"abstract":"In this study, driving condition classification and recognition based adaptive optimal control strategy is developed for new type four wheel drive plug-in hybrid electric vehicle (PHEV). First, power characteristics of the proposed PHEV are analysed. The basic rule based and adaptive optimal control strategies are developed. According to the support vector machine (SVM) based classification theory, the RBF neural network kernel function is introduced and the multi classification SVM with the one-against-one method is selected. The feature parameters are then determined and extracted using real road experiment data. It is seen from the classification results that RBF kernel function based SVM has relatively high accuracy of 93.2%. Based on the developed energy management strategy library and driving cost theory, adaptive optimal control strategy is developed using Matlab/Simulink. It is found from the simulation results that the adaptive optimal control achieves the efficiency increase of 13.4%, which implies validity of the proposed adaptive optimal control strategy.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1504/IJEHV.2019.101299","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47161558","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 : 2019-07-26DOI: 10.1504/IJEHV.2019.101298
Jing Gan, Xiao-bin Fan, Zeng Song
The vehicle performance test system is usually an indispensable part of the automobile industry. Its performance test results are an important indicator to measure the performance of vehicles. By analysing and comparing the characteristics of performance test system of traditional automobile and electric vehicle, the development direction of vehicle performance test system is given. This paper introduces the development status of vehicle performance testing system in foreign countries from the aspects of universalisation, standardisation and high performance, and puts forward some opinions on how to strengthen international technical cooperation and exchanges and constantly narrow the gap between China and international testing level.
{"title":"Research review on vehicle performance testing system","authors":"Jing Gan, Xiao-bin Fan, Zeng Song","doi":"10.1504/IJEHV.2019.101298","DOIUrl":"https://doi.org/10.1504/IJEHV.2019.101298","url":null,"abstract":"The vehicle performance test system is usually an indispensable part of the automobile industry. Its performance test results are an important indicator to measure the performance of vehicles. By analysing and comparing the characteristics of performance test system of traditional automobile and electric vehicle, the development direction of vehicle performance test system is given. This paper introduces the development status of vehicle performance testing system in foreign countries from the aspects of universalisation, standardisation and high performance, and puts forward some opinions on how to strengthen international technical cooperation and exchanges and constantly narrow the gap between China and international testing level.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1504/IJEHV.2019.101298","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48487812","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 : 2019-07-26DOI: 10.1504/IJEHV.2019.101273
U. Panwar, Anil Kumar, D. Chakrabarti
Electric vehicle is not a new concept, it is prominent from 1828 but due to improvement in internal combustion engine technology it shifted to the sidelines. This concept has resurfaced in the past decade or two for sustainable and green future but faces a lot of barriers for proper implementation in metropolitan area. India's dependency on fossil fuels, the lack of lithium reserves, the grid integration problems, heavy loads of electric vehicles along with lack of charging station infrastructure in metropolitan area has become a major barrier in the smooth acceptance of electric vehicles. This paper deals with the barriers in implementation of electric vehicles in metropolitan area. India needs to improve and enforce proper regulatory framework, and to work on consumer and public awareness to overcome these barriers.
{"title":"Barriers in implementation of electric vehicles in India","authors":"U. Panwar, Anil Kumar, D. Chakrabarti","doi":"10.1504/IJEHV.2019.101273","DOIUrl":"https://doi.org/10.1504/IJEHV.2019.101273","url":null,"abstract":"Electric vehicle is not a new concept, it is prominent from 1828 but due to improvement in internal combustion engine technology it shifted to the sidelines. This concept has resurfaced in the past decade or two for sustainable and green future but faces a lot of barriers for proper implementation in metropolitan area. India's dependency on fossil fuels, the lack of lithium reserves, the grid integration problems, heavy loads of electric vehicles along with lack of charging station infrastructure in metropolitan area has become a major barrier in the smooth acceptance of electric vehicles. This paper deals with the barriers in implementation of electric vehicles in metropolitan area. India needs to improve and enforce proper regulatory framework, and to work on consumer and public awareness to overcome these barriers.","PeriodicalId":43639,"journal":{"name":"International Journal of Electric and Hybrid Vehicles","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1504/IJEHV.2019.101273","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48610381","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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