This paper designs a CLLC converter for the bidirectional on-board charger which has fully symmetrical parameters. Based on the three-stage charging strategy, the small-signal model of the converter is established and verified, and the closed-loop PFM control is realized. Finally, a planar transformer with integrated leakage inductor is designed and a 1. 2kW experimental prototype is built.
{"title":"Design and Modeling of CLLC Converter for Bidirectional On-Board Charger","authors":"Zheng Bai, Hao Liu, Jingwei Shao, Xiangjun Zhang, Jingyun Gu, Dianguo Xu","doi":"10.1109/ITECAsia-Pacific56316.2022.9942145","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942145","url":null,"abstract":"This paper designs a CLLC converter for the bidirectional on-board charger which has fully symmetrical parameters. Based on the three-stage charging strategy, the small-signal model of the converter is established and verified, and the closed-loop PFM control is realized. Finally, a planar transformer with integrated leakage inductor is designed and a 1. 2kW experimental prototype is built.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"9 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83892929","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}
In modern aircraft, there is a huge demand for high power high step-up (HPHS) DC-DC conversion from 28V to 270V or even higher voltage, such as Start Power Unit (SPU) and backup power supply systems. Due to high efficiency, high power density, low EMI, and soft-switching capability, LLC resonant topology are receiving special attention. However, when it comes to HPHS applications, original LLC resonant topology will encounter some limitations, resulting poor parameter controllability, low power density and low efficiency. This paper first analyzed the fundamental causes of these limitations. Then, solutions are given in terms of circuit topology and system architecture, respectively. A 5kW 2SV/222V prototype was designed, fabricated and tested. The feasibility of proposed solutions is validated.
{"title":"Limitations and Solutions of LLC Topology in High Power High Step-up Applications on Aircraft","authors":"Shuangyi Zhong, Xin Zhao, Xuanlyu Wu, Xiliang Chen, Bei Wang, Xiaohua Wu","doi":"10.1109/ITECAsia-Pacific56316.2022.9942114","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942114","url":null,"abstract":"In modern aircraft, there is a huge demand for high power high step-up (HPHS) DC-DC conversion from 28V to 270V or even higher voltage, such as Start Power Unit (SPU) and backup power supply systems. Due to high efficiency, high power density, low EMI, and soft-switching capability, LLC resonant topology are receiving special attention. However, when it comes to HPHS applications, original LLC resonant topology will encounter some limitations, resulting poor parameter controllability, low power density and low efficiency. This paper first analyzed the fundamental causes of these limitations. Then, solutions are given in terms of circuit topology and system architecture, respectively. A 5kW 2SV/222V prototype was designed, fabricated and tested. The feasibility of proposed solutions is validated.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"86 7 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84000820","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 : 2022-10-28DOI: 10.1109/ITECAsia-Pacific56316.2022.9942202
Xueqing Wang, Zifan Zhang, Shaowei Ren, Yao Mao, Jianwei Shen, Z. Wang
This paper, proposed a fault-tolerant scheme to optimize the fault-tolerant performance of standard three-phase permanent-magnet synchronous motor (PMSM) drives under open-phase and open-switch faults. In the proposed scheme for the open-phase fault, the current references considering reluctance torque and overcurrent endurance of motor drive are derived. On this basis, the fault-tolerant current references are further optimized to reduce the copper loss without increasing the torque ripple. In the proposed scheme for open-switch fault, a two-mode fault-tolerant control is designed to reduce copper loss and torque ripple by using the remaining healthy switch in the faulty leg. The validity of the proposed scheme is proved by experiments.
{"title":"Fault-Tolerant Control of Standard Three-Phase PMSM Drives Considering Copper Loss","authors":"Xueqing Wang, Zifan Zhang, Shaowei Ren, Yao Mao, Jianwei Shen, Z. Wang","doi":"10.1109/ITECAsia-Pacific56316.2022.9942202","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942202","url":null,"abstract":"This paper, proposed a fault-tolerant scheme to optimize the fault-tolerant performance of standard three-phase permanent-magnet synchronous motor (PMSM) drives under open-phase and open-switch faults. In the proposed scheme for the open-phase fault, the current references considering reluctance torque and overcurrent endurance of motor drive are derived. On this basis, the fault-tolerant current references are further optimized to reduce the copper loss without increasing the torque ripple. In the proposed scheme for open-switch fault, a two-mode fault-tolerant control is designed to reduce copper loss and torque ripple by using the remaining healthy switch in the faulty leg. The validity of the proposed scheme is proved by experiments.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"72 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90731621","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}
The semibridgrless active rectifier for inductively coupled power transfer (ICPT) system is proposed and the energy injection control for the semibridgeless active rectifier to realize the constant output voltage in this paper. Theoretical analysis show that with the proposed control strategy, the output voltage can be regulated without communication between the primary side and secondary side. The zero voltage switching (ZVS) of the inverter can be realized. Finally, the simulation results are provided, the feasibility and the good dynamic performance of the proposed strategy are verified.
{"title":"A Constant Output Voltage Control Strategy of Inductively Coupled Power Transfer System for Rail Transit System","authors":"Jixin Yang, Liming Shi, Zhenggang Yin, Wenjing Tang","doi":"10.1109/ITECAsia-Pacific56316.2022.9942100","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942100","url":null,"abstract":"The semibridgrless active rectifier for inductively coupled power transfer (ICPT) system is proposed and the energy injection control for the semibridgeless active rectifier to realize the constant output voltage in this paper. Theoretical analysis show that with the proposed control strategy, the output voltage can be regulated without communication between the primary side and secondary side. The zero voltage switching (ZVS) of the inverter can be realized. Finally, the simulation results are provided, the feasibility and the good dynamic performance of the proposed strategy are verified.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"1970 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91358531","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}
A numerical investigation has been conducted to improve the transient thermal performance of SiC modules during varied loads, and phase change materials is utilized as a thermal buffer layer and integrated into SiC modules under SiC MOSFETs. The influences of PCM on the instantaneous overload capacity and temperature fluctuation during power cycle have been explored. As for the overload capacity, PCM could protect SiC modules from over-heating under a 1.5 per unit heat flux as high as 500 W/cm2 for over 10 s, which is critical for safety of power system under the short-circuit faults. While for power cycles, SiC modules exhibits a much lower temperature swings when tp < 20 s, and the maximum reduction could achieve 12 K. Additionally, the geometries of PCM containers makes a great differences on the transient temperature responses of PCM-integrated modules, and special attention should been given to balance the heat absorption and thermal resistance of PCM. In the present work, a container with branch-like fins shows the best thermal performance for both overload conditions and power cycles.
{"title":"Transient thermal management of SiC power modules by an in-built thermal buffer layer","authors":"Weiyu Tang, Junye Li, Junliang Lu, Zan Wu, Kuang Sheng","doi":"10.1109/ITECAsia-Pacific56316.2022.9942153","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942153","url":null,"abstract":"A numerical investigation has been conducted to improve the transient thermal performance of SiC modules during varied loads, and phase change materials is utilized as a thermal buffer layer and integrated into SiC modules under SiC MOSFETs. The influences of PCM on the instantaneous overload capacity and temperature fluctuation during power cycle have been explored. As for the overload capacity, PCM could protect SiC modules from over-heating under a 1.5 per unit heat flux as high as 500 W/cm2 for over 10 s, which is critical for safety of power system under the short-circuit faults. While for power cycles, SiC modules exhibits a much lower temperature swings when tp < 20 s, and the maximum reduction could achieve 12 K. Additionally, the geometries of PCM containers makes a great differences on the transient temperature responses of PCM-integrated modules, and special attention should been given to balance the heat absorption and thermal resistance of PCM. In the present work, a container with branch-like fins shows the best thermal performance for both overload conditions and power cycles.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"18 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89052925","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 : 2022-10-28DOI: 10.1109/ITECAsia-Pacific56316.2022.9941849
Yu Li, Bo Wang, Yong Yu, Dianguo Xu
The offline parameter identification of induction motor can provide solid basis for the design of high dynamic response controllers and observers. However, there exists identification coupling problem among different parameters, especially rotor resistance, leakage inductance, and mutual inductance. To solve this problem, a decoupled offline strategy is proposed for induction motor considering the dynamic model in this paper. First, the rotor resistance and leakage inductance are decoupling identified by high frequency injection method, so as to improve the identification accuracy. Second, the dynamic model is applied for the mutual inductance identification. By injecting the designed symmetrical track current, the influence of inverter nonlinearity and stator resistance can be suppressed, improving the stability and accuracy of mutual inductance identification. The experimental results from a 3. 7kW induction motor drive system verify the effectiveness of the studied identification strategy.
{"title":"Decoupled Offline Parameter Identification of Induction Motors","authors":"Yu Li, Bo Wang, Yong Yu, Dianguo Xu","doi":"10.1109/ITECAsia-Pacific56316.2022.9941849","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9941849","url":null,"abstract":"The offline parameter identification of induction motor can provide solid basis for the design of high dynamic response controllers and observers. However, there exists identification coupling problem among different parameters, especially rotor resistance, leakage inductance, and mutual inductance. To solve this problem, a decoupled offline strategy is proposed for induction motor considering the dynamic model in this paper. First, the rotor resistance and leakage inductance are decoupling identified by high frequency injection method, so as to improve the identification accuracy. Second, the dynamic model is applied for the mutual inductance identification. By injecting the designed symmetrical track current, the influence of inverter nonlinearity and stator resistance can be suppressed, improving the stability and accuracy of mutual inductance identification. The experimental results from a 3. 7kW induction motor drive system verify the effectiveness of the studied identification strategy.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"111 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82795498","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 : 2022-10-28DOI: 10.1109/ITECAsia-Pacific56316.2022.9942179
Zihao Zhao, Shaoxuan Zhang, Jing Zhang, Weichen Wang
With the gradual depletion of fossil energy, distributed power supply and electric vehicle become one of the direction of energy development in the future, and get rapid development. Its randomness also brings new challenges and opportunities to the development of power grid. In this paper, considering the demand-side response of EV users and the cost of power network construction, a dynamic time-varying price model is developed to make EV charge in valley as much as possible to consume the remaining photovoltaic power of the basic load in the supply area, and discharge in peak time to maintain the power balance in the power network, so as to reduce the difference between peak and valley and ensure the stability of the power network. Delay investment in grid infrastructure. At the same time, users can make profits through demand-side response, improve charging and discharging satisfaction, and achieve a win-win situation. The example shows that the collaborative optimization strategy proposed in this paper can better improve the economy of distribution network operation with a large number of distributed power sources and electric vehicles connected.
{"title":"Research on Collaborative Optimization of Distributed Generation and Electric Vehicle Considering Time-Of-Use Price","authors":"Zihao Zhao, Shaoxuan Zhang, Jing Zhang, Weichen Wang","doi":"10.1109/ITECAsia-Pacific56316.2022.9942179","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942179","url":null,"abstract":"With the gradual depletion of fossil energy, distributed power supply and electric vehicle become one of the direction of energy development in the future, and get rapid development. Its randomness also brings new challenges and opportunities to the development of power grid. In this paper, considering the demand-side response of EV users and the cost of power network construction, a dynamic time-varying price model is developed to make EV charge in valley as much as possible to consume the remaining photovoltaic power of the basic load in the supply area, and discharge in peak time to maintain the power balance in the power network, so as to reduce the difference between peak and valley and ensure the stability of the power network. Delay investment in grid infrastructure. At the same time, users can make profits through demand-side response, improve charging and discharging satisfaction, and achieve a win-win situation. The example shows that the collaborative optimization strategy proposed in this paper can better improve the economy of distribution network operation with a large number of distributed power sources and electric vehicles connected.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"13 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87533470","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 : 2022-10-28DOI: 10.1109/ITECAsia-Pacific56316.2022.9942204
Xu Zhu, Rongguan Li, Wu Chen, Lingling Cao, Renjie Hu
A DC transformer utilizing modular multilevel converter (MMC) structure and series-connected switches incurs high current stress and results in low system efficiency under low-voltage and light-load conditions. An optimization control strategy utilizing the phase shift on the low-voltage (LV)-side full bridge is proposed. It is shown that by introducing the zero state to the output voltage of the LV-side full bridge the spikes in inductor current are eliminated thus reducing the current stress of switches and system power losses. While maintaining the power regulation capability of the circuit optimal current stress is achieved under different operating modes by segmented phase shift angel control. The soft-switching characteristic of power switches is unchanged after applying this strategy. The proposed control strategy is verified by simulation and experimental experiment results.
{"title":"A Current Optimization Strategy for a Hybrid DC Transformer with MMC Structure and Series-connected Switches","authors":"Xu Zhu, Rongguan Li, Wu Chen, Lingling Cao, Renjie Hu","doi":"10.1109/ITECAsia-Pacific56316.2022.9942204","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942204","url":null,"abstract":"A DC transformer utilizing modular multilevel converter (MMC) structure and series-connected switches incurs high current stress and results in low system efficiency under low-voltage and light-load conditions. An optimization control strategy utilizing the phase shift on the low-voltage (LV)-side full bridge is proposed. It is shown that by introducing the zero state to the output voltage of the LV-side full bridge the spikes in inductor current are eliminated thus reducing the current stress of switches and system power losses. While maintaining the power regulation capability of the circuit optimal current stress is achieved under different operating modes by segmented phase shift angel control. The soft-switching characteristic of power switches is unchanged after applying this strategy. The proposed control strategy is verified by simulation and experimental experiment results.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"14 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87536728","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 : 2022-10-28DOI: 10.1109/ITECAsia-Pacific56316.2022.9942159
Zhiyong Qu, Jing Lin, Xiaoqiong He
The three-phase to single-phase three-level converter is the core equipment in the advanced traction power supply system. The voltage equalization and second ripple on the dc-link are not conducive to not only distorting the three-phase grid side current and the inverter output voltage, but also leading to the degradation of the life of the power electronic converter devices. In this paper, a three-phase to single-phase three-level converter topology based on a symmetrical half-bridge active power decoupling circuit is proposed. This structure can maintain the balance of the two voltages on the dc-link and decouple the ripple power, thereby ensuring the instantaneous power flow balance between the three-phase grid side and the half-bridge decoupling circuit and the load, and can greatly reduce the number of required passive components and volume. In order to achieve proper closed-loop regulation, a unified coordinated control strategy for voltage equalization and second ripple is proposed.
{"title":"DC- Link Voltage Equalization and Second Ripple Suppression Control Strategy for Three-Phase To Single-Phase Converters","authors":"Zhiyong Qu, Jing Lin, Xiaoqiong He","doi":"10.1109/ITECAsia-Pacific56316.2022.9942159","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9942159","url":null,"abstract":"The three-phase to single-phase three-level converter is the core equipment in the advanced traction power supply system. The voltage equalization and second ripple on the dc-link are not conducive to not only distorting the three-phase grid side current and the inverter output voltage, but also leading to the degradation of the life of the power electronic converter devices. In this paper, a three-phase to single-phase three-level converter topology based on a symmetrical half-bridge active power decoupling circuit is proposed. This structure can maintain the balance of the two voltages on the dc-link and decouple the ripple power, thereby ensuring the instantaneous power flow balance between the three-phase grid side and the half-bridge decoupling circuit and the load, and can greatly reduce the number of required passive components and volume. In order to achieve proper closed-loop regulation, a unified coordinated control strategy for voltage equalization and second ripple is proposed.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"9 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80945640","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 : 2022-10-28DOI: 10.1109/ITECAsia-Pacific56316.2022.9941847
Ziyan Zhang, Dongwei Yao, Feng Wu, Junhao Shen
To improve the prediction accuracy and calculation speed of vehicle velocity prediction under a highway vehicle-to-vehicle (V2V) environment, a velocity prediction strategy combined with traffic information is proposed under the corresponding scenario. First, the highway scenario is set up. In addition, the general regressive neural network (GRNN) combined with front vehicle information is used in the highway scenario, which constructs a GRNN velocity prediction model with multi-information fusion. Then the model in the highway scenario is simulated, and the optimal model parameters are extracted, which are used to verify the prediction model in other operating conditions. As a result, the simulation data shows that compared with the prediction strategy using only historical vehicle velocity data, the prediction accuracy of the fusion prediction strategy using the optimal parameters is improved by 14.4% in the highway scenario under the V2V environment.
{"title":"Real-time Vehicle Velocity Prediction Strategy under Highway Vehicle-to-vehicle Environment","authors":"Ziyan Zhang, Dongwei Yao, Feng Wu, Junhao Shen","doi":"10.1109/ITECAsia-Pacific56316.2022.9941847","DOIUrl":"https://doi.org/10.1109/ITECAsia-Pacific56316.2022.9941847","url":null,"abstract":"To improve the prediction accuracy and calculation speed of vehicle velocity prediction under a highway vehicle-to-vehicle (V2V) environment, a velocity prediction strategy combined with traffic information is proposed under the corresponding scenario. First, the highway scenario is set up. In addition, the general regressive neural network (GRNN) combined with front vehicle information is used in the highway scenario, which constructs a GRNN velocity prediction model with multi-information fusion. Then the model in the highway scenario is simulated, and the optimal model parameters are extracted, which are used to verify the prediction model in other operating conditions. As a result, the simulation data shows that compared with the prediction strategy using only historical vehicle velocity data, the prediction accuracy of the fusion prediction strategy using the optimal parameters is improved by 14.4% in the highway scenario under the V2V environment.","PeriodicalId":45126,"journal":{"name":"Asia-Pacific Journal-Japan Focus","volume":"85 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80978116","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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