Pub Date : 2015-09-01DOI: 10.1109/VTCFall.2015.7391093
A. Burke, Hengbing Zhao
This paper is concerned with supercapacitors (electrochemical capacitors) and their applications in electric drive vehicles in place of or in combination with batteries. The electric drive vehicles considered are hybrid vehicles and fuel cell vehicles. The first section of the paper presents recent test data for advanced proto-type devices. The data for the new carbon/carbon device from Skeleton Technologies showed an energy density of 9 Wh/kg and 95% efficient power capability of 1730 W/kg. Both of these characteristics are significantly better than those of commercially available devices. Test data are shown for a hybrid supercapacitor from Vunasko that has an energy density greater than 30 Wh/kg and a 95% efficient power capability of 3120 W/kg. This device has the best performance of any supercapacitor device tested at TIC Davis to date. Various vehicle applications of supercapacitors have been reviewed in detail. Simulation results are presented for light duty vehicles using supercapacitors in place of lithium batteries in hybrid and fuel cell vehicles. It was found in all cases that the vehicles using the supercapacitors had the same as or better performance than those using batteries and in general were more efficient. The cost of supercapacitors compared to lithium batteries was discussed briefly. It was shown that when one recognizes that the energy stored in the capacitors is less than 1/10 that in the batteries for hybrid applications, the price of supercapacitors needs to decrease to about .5.1 cent Farad for capacitors to be cost competitive with high power batteries at $500-700/kWh. In addition, there is a good possibility that the life of the capacitors would be equal to that of the hybrid vehicles.
{"title":"Present and future applications of supercapacitors in electric and hybrid vehicles","authors":"A. Burke, Hengbing Zhao","doi":"10.1109/VTCFall.2015.7391093","DOIUrl":"https://doi.org/10.1109/VTCFall.2015.7391093","url":null,"abstract":"This paper is concerned with supercapacitors (electrochemical capacitors) and their applications in electric drive vehicles in place of or in combination with batteries. The electric drive vehicles considered are hybrid vehicles and fuel cell vehicles. The first section of the paper presents recent test data for advanced proto-type devices. The data for the new carbon/carbon device from Skeleton Technologies showed an energy density of 9 Wh/kg and 95% efficient power capability of 1730 W/kg. Both of these characteristics are significantly better than those of commercially available devices. Test data are shown for a hybrid supercapacitor from Vunasko that has an energy density greater than 30 Wh/kg and a 95% efficient power capability of 3120 W/kg. This device has the best performance of any supercapacitor device tested at TIC Davis to date. Various vehicle applications of supercapacitors have been reviewed in detail. Simulation results are presented for light duty vehicles using supercapacitors in place of lithium batteries in hybrid and fuel cell vehicles. It was found in all cases that the vehicles using the supercapacitors had the same as or better performance than those using batteries and in general were more efficient. The cost of supercapacitors compared to lithium batteries was discussed briefly. It was shown that when one recognizes that the energy stored in the capacitors is less than 1/10 that in the batteries for hybrid applications, the price of supercapacitors needs to decrease to about .5.1 cent Farad for capacitors to be cost competitive with high power batteries at $500-700/kWh. In addition, there is a good possibility that the life of the capacitors would be equal to that of the hybrid vehicles.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121184941","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 : 2014-12-19DOI: 10.1109/IEVC.2014.7056223
Alireza Soroudi, A. Keane
With the introduction of new technologies like electric vehicles and smart grids the operation and planning of power systems are subject to major changes. These technologies can bring various ftexibilities to different entities involved in decision making. This paper proposes a robust optimization based method to optimal charging/discharging of electric vehicles considering the electricity price uncertainties. The objective function is defined as the total operating costs of energy procurement in distribution networks which is tried to be minimized while considering the technical constraints of the problem.
{"title":"Robust optimization based EV charging","authors":"Alireza Soroudi, A. Keane","doi":"10.1109/IEVC.2014.7056223","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056223","url":null,"abstract":"With the introduction of new technologies like electric vehicles and smart grids the operation and planning of power systems are subject to major changes. These technologies can bring various ftexibilities to different entities involved in decision making. This paper proposes a robust optimization based method to optimal charging/discharging of electric vehicles considering the electricity price uncertainties. The objective function is defined as the total operating costs of energy procurement in distribution networks which is tried to be minimized while considering the technical constraints of the problem.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129443610","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 : 2014-12-17DOI: 10.1109/IEVC.2014.7056169
Hengbing Zhao, A. Burke
An intelligent energy management approach for a solar powered EV charging station with energy storage has been studied and demonstrated for a level 2 charger at the University of California-Davis West Village. The approach introduces solar PV electrical energy forecasting and EV charging demand projection to optimize the energy management of the charging station. The percentage of cloud cover is extracted from a weather forecast website for estimating the available PV electrical energy. A linear fit of the historical EV charging load from the same day of the week over the previous six weeks is employed for extracting the charging pattern of the workplace EV charging station. Both simulations and actual operation show that intelligent energy management for a charging station with a buffer battery can reduce impacts of the EV charging system on utility grids in terms of peak power demand and energy exchange, reduce grid system losses, and benefit the charging station owner through the Time-of-Use rate plans.
{"title":"An intelligent solar powered battery buffered EV charging station with solar electricity forecasting and EV charging load projection functions","authors":"Hengbing Zhao, A. Burke","doi":"10.1109/IEVC.2014.7056169","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056169","url":null,"abstract":"An intelligent energy management approach for a solar powered EV charging station with energy storage has been studied and demonstrated for a level 2 charger at the University of California-Davis West Village. The approach introduces solar PV electrical energy forecasting and EV charging demand projection to optimize the energy management of the charging station. The percentage of cloud cover is extracted from a weather forecast website for estimating the available PV electrical energy. A linear fit of the historical EV charging load from the same day of the week over the previous six weeks is employed for extracting the charging pattern of the workplace EV charging station. Both simulations and actual operation show that intelligent energy management for a charging station with a buffer battery can reduce impacts of the EV charging system on utility grids in terms of peak power demand and energy exchange, reduce grid system losses, and benefit the charging station owner through the Time-of-Use rate plans.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133474409","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 : 2014-12-01DOI: 10.1109/IEVC.2014.7056078
Zeming Jiang, L. Shalalfeh, M. Beshir
With the growing penetration of the electric vehicles to our daily life owing to their economic and environmental benefits, there will be both opportunities and challenges to the utilities when adopting plug-in electric vehicles (PEV) to the distribution network. In this paper, a thorough analysis based on real-world project is conducted to evaluate the impact of electric vehicles infrastructure on the grid relating to system load flow, load factor, and voltage stability. Chatsworth distribution system was selected and tested along with different case scenarios utilizing the electrical distribution design (ED D) software to find out the potential impacts to the grid.
{"title":"Impact of electric vehicle infrastructure on the city of Chatsworth distribution system","authors":"Zeming Jiang, L. Shalalfeh, M. Beshir","doi":"10.1109/IEVC.2014.7056078","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056078","url":null,"abstract":"With the growing penetration of the electric vehicles to our daily life owing to their economic and environmental benefits, there will be both opportunities and challenges to the utilities when adopting plug-in electric vehicles (PEV) to the distribution network. In this paper, a thorough analysis based on real-world project is conducted to evaluate the impact of electric vehicles infrastructure on the grid relating to system load flow, load factor, and voltage stability. Chatsworth distribution system was selected and tested along with different case scenarios utilizing the electrical distribution design (ED D) software to find out the potential impacts to the grid.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116692613","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 : 2014-12-01DOI: 10.1109/IEVC.2014.7056138
G. Campatelli, A. Meneghin, Filippo Benesperi, R. Barbieri
Within the last years, under the push of the most important institutions, new models of private and public transport systems have been studied in order to reduce polluting impact of petroleum-based public and private mobility. EU focuses its attention especially on electric mobility, which seems the best solution in terms of economic and environmental sustainability. Following this idea, new business models are requested for major actors of urban transport system. This paper focuses on the development of a simulation approach to check the model economic feasibility and to verify how the proposed electric mobility system can be applied in a real contest. The business model chosen is the one where PTP (public transport provider) acts as CPM (charging point manager) with a CSP (charging system provider) and ancillary services. In particular, an electric park and ride (eP+R) that provides new electric mobility services has been modeled. The system has been tested through a specific simulation tool and the analysis has been based on real data that represents the current transport system of Florence (Italy).
{"title":"Implementing electric mobility new business model in future scenario: the electric park and ride system","authors":"G. Campatelli, A. Meneghin, Filippo Benesperi, R. Barbieri","doi":"10.1109/IEVC.2014.7056138","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056138","url":null,"abstract":"Within the last years, under the push of the most important institutions, new models of private and public transport systems have been studied in order to reduce polluting impact of petroleum-based public and private mobility. EU focuses its attention especially on electric mobility, which seems the best solution in terms of economic and environmental sustainability. Following this idea, new business models are requested for major actors of urban transport system. This paper focuses on the development of a simulation approach to check the model economic feasibility and to verify how the proposed electric mobility system can be applied in a real contest. The business model chosen is the one where PTP (public transport provider) acts as CPM (charging point manager) with a CSP (charging system provider) and ancillary services. In particular, an electric park and ride (eP+R) that provides new electric mobility services has been modeled. The system has been tested through a specific simulation tool and the analysis has been based on real data that represents the current transport system of Florence (Italy).","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117066757","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 : 2014-12-01DOI: 10.1109/IEVC.2014.7056079
Andrea Lanna, F. Liberati, L. Zuccaro, A. Giorgio
In this paper a rationale for the deployment of Future Internet based applications in the field of Electric Vehicles (EVs) smart charging is presented. The focus is on the Connected Device Interface (CDI) Generic Enabler (GE) and the Network Information and Controller (NetIC) GE, which are recognized to have a potential impact on the charging control problem and the configuration of communications networks within reconfigurable clusters of charging points. The CDI GE can be used for capturing the driver feedback in terms of Quality of Experience (QoE) in those situations where the charging power is abruptly limited as a consequence of short term grid needs, like the shedding action asked by the Transmission System Operator to the Distribution System Operator aimed at clearing networks contingencies due to the loss of a transmission line or large wind power fluctuations. The NetIC GE can be used when a master Electric Vehicle Supply Equipment (EVSE) hosts the Load Area Controller, responsible for managing simultaneous charging sessions within a given Load Area (LA); the reconfiguration of distribution grid topology results in shift of EVSEs among LAs, then reallocation of slave EVSEs is needed. Involved actors, equipment, communications and processes are identified through the standardized framework provided by the Smart Grid Architecture Model (SGAM).
{"title":"Electric Vehicles charging control based on future internet generic enablers","authors":"Andrea Lanna, F. Liberati, L. Zuccaro, A. Giorgio","doi":"10.1109/IEVC.2014.7056079","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056079","url":null,"abstract":"In this paper a rationale for the deployment of Future Internet based applications in the field of Electric Vehicles (EVs) smart charging is presented. The focus is on the Connected Device Interface (CDI) Generic Enabler (GE) and the Network Information and Controller (NetIC) GE, which are recognized to have a potential impact on the charging control problem and the configuration of communications networks within reconfigurable clusters of charging points. The CDI GE can be used for capturing the driver feedback in terms of Quality of Experience (QoE) in those situations where the charging power is abruptly limited as a consequence of short term grid needs, like the shedding action asked by the Transmission System Operator to the Distribution System Operator aimed at clearing networks contingencies due to the loss of a transmission line or large wind power fluctuations. The NetIC GE can be used when a master Electric Vehicle Supply Equipment (EVSE) hosts the Load Area Controller, responsible for managing simultaneous charging sessions within a given Load Area (LA); the reconfiguration of distribution grid topology results in shift of EVSEs among LAs, then reallocation of slave EVSEs is needed. Involved actors, equipment, communications and processes are identified through the standardized framework provided by the Smart Grid Architecture Model (SGAM).","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121340401","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 : 2014-12-01DOI: 10.1109/IEVC.2014.7056183
U. Guida, S. Leonard
The Zero Emission Urban Bus System [ZeEUS] project, cofunded by the European Commission's FP7 Programme and coordinated by UITP, aims to bring electrification to the heart of the urban bus network. Eight live urban demonstrations in six European countries will test and validate a range of plug-in hybrid, full electric and battery trolley buses with fast and slow charging strategies with different energy supply modes. The results and experiences gathered will help support decision makers with guidelines and tools on 'if', 'how' and 'when' to introduce electric buses.
{"title":"ZeEUS: Zero Emission Urban Bus System","authors":"U. Guida, S. Leonard","doi":"10.1109/IEVC.2014.7056183","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056183","url":null,"abstract":"The Zero Emission Urban Bus System [ZeEUS] project, cofunded by the European Commission's FP7 Programme and coordinated by UITP, aims to bring electrification to the heart of the urban bus network. Eight live urban demonstrations in six European countries will test and validate a range of plug-in hybrid, full electric and battery trolley buses with fast and slow charging strategies with different energy supply modes. The results and experiences gathered will help support decision makers with guidelines and tools on 'if', 'how' and 'when' to introduce electric buses.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"365 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115471812","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 : 2014-12-01DOI: 10.1109/IEVC.2014.7056165
A. Rotondale, M. Villani, L. Castellini
Coaxial magnetic gears with permanent magnets have a very simple structure with performance comparable with that of mechanical gears. Several solutions with different gear ratios are proposed and the electromagnetic characteristics are analyzed by finite element methods.
{"title":"Analysis of high-performance magnetic gears for electric vehicle","authors":"A. Rotondale, M. Villani, L. Castellini","doi":"10.1109/IEVC.2014.7056165","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056165","url":null,"abstract":"Coaxial magnetic gears with permanent magnets have a very simple structure with performance comparable with that of mechanical gears. Several solutions with different gear ratios are proposed and the electromagnetic characteristics are analyzed by finite element methods.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122762025","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 : 2014-12-01DOI: 10.1109/IEVC.2014.7056146
N. Bianchi, E. Fornasiero, Enrico Carraro, S. Bolognani, M. Castiello
It is recently demonstrated that the synchronous reluctance motor is well suited for electric as well as for hybrid electric vehicles. Of course, a proper rotor design is necessary, since the main torque is due to the rotor anisotropy, that is, the permeance difference between the direct- and the quadrature-axis. The flux barrier ends are placed so as to reduce the torque ripple due to the slot harmonics. The torque ripple is also reduced adopting rotor asymmetries. The impact of the rotor design on the motor performance is presented deeply, showing several experimental test results carried out on synchronous reluctance motors with different rotor geometries. Permanent magnet can be inset in the flux barriers to assist the synchronous reluctance motor improving its capabilities. The main advantages and drawbacks of the permanent magnet adoption are highlighted.
{"title":"Electric vehicle traction based on a PM assisted synchronous reluctance motor","authors":"N. Bianchi, E. Fornasiero, Enrico Carraro, S. Bolognani, M. Castiello","doi":"10.1109/IEVC.2014.7056146","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056146","url":null,"abstract":"It is recently demonstrated that the synchronous reluctance motor is well suited for electric as well as for hybrid electric vehicles. Of course, a proper rotor design is necessary, since the main torque is due to the rotor anisotropy, that is, the permeance difference between the direct- and the quadrature-axis. The flux barrier ends are placed so as to reduce the torque ripple due to the slot harmonics. The torque ripple is also reduced adopting rotor asymmetries. The impact of the rotor design on the motor performance is presented deeply, showing several experimental test results carried out on synchronous reluctance motors with different rotor geometries. Permanent magnet can be inset in the flux barriers to assist the synchronous reluctance motor improving its capabilities. The main advantages and drawbacks of the permanent magnet adoption are highlighted.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"389 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122991835","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 : 2014-12-01DOI: 10.1109/IEVC.2014.7056135
Ignacio Benítez, Carlos Blasco, A. Mocholí, A. Quijano
The aim of this work is the identification of typical patterns in urban mobility on the basis of real data and advanced data mining algorithms. To achieve this goal a trajectory pattern recognition system has been developed. This system encompasses two steps: the first one is a fast K-means clustering to group the trajectories according to their start and destination coordinates and the second one is the classification over a Self-Organizing Map of the trajectories grouped before. Previously to this second step, the system standardizes the trajectories to equal length criterion using Dynamic Time Warping. This work also includes the results of testing the system on a real database of fifty trajectories of trucks.
{"title":"A two-step process for clustering electric vehicle trajectories","authors":"Ignacio Benítez, Carlos Blasco, A. Mocholí, A. Quijano","doi":"10.1109/IEVC.2014.7056135","DOIUrl":"https://doi.org/10.1109/IEVC.2014.7056135","url":null,"abstract":"The aim of this work is the identification of typical patterns in urban mobility on the basis of real data and advanced data mining algorithms. To achieve this goal a trajectory pattern recognition system has been developed. This system encompasses two steps: the first one is a fast K-means clustering to group the trajectories according to their start and destination coordinates and the second one is the classification over a Self-Organizing Map of the trajectories grouped before. Previously to this second step, the system standardizes the trajectories to equal length criterion using Dynamic Time Warping. This work also includes the results of testing the system on a real database of fifty trajectories of trucks.","PeriodicalId":223794,"journal":{"name":"2014 IEEE International Electric Vehicle Conference (IEVC)","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124017695","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：