Pub Date : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213586
Cheol-Hee Jo, Seung-Min Kim, Min-Yeong Choe, So-Jeong Kang, Dong-Hee Kim
This paper proposes a design methodology of a bidirectional resonant CLLC converter with dual resonant frequencies for a wide voltage range. The proposed CLLC resonance parameter design method can improve the efficiency and control strategy of the converter by operating at the fixed two resonant frequencies according to the battery charging/discharging mode. A 3.6-kW experimental prototype is configured and evaluated to verify the proposed design method.
{"title":"Design Methodology of Bidirectional Resonant CLLC Converter with Dual Resonant Frequencies for Wide Voltage Range","authors":"Cheol-Hee Jo, Seung-Min Kim, Min-Yeong Choe, So-Jeong Kang, Dong-Hee Kim","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213586","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213586","url":null,"abstract":"This paper proposes a design methodology of a bidirectional resonant CLLC converter with dual resonant frequencies for a wide voltage range. The proposed CLLC resonance parameter design method can improve the efficiency and control strategy of the converter by operating at the fixed two resonant frequencies according to the battery charging/discharging mode. A 3.6-kW experimental prototype is configured and evaluated to verify the proposed design method.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":" 79","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132040329","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213848
Hongchang Cui, Fengtao Yang, Hang Kong, Chenxu Zhao, Junhui Yang, Yang Nie, Feng Wang, Laili Wang, K. Gao
Dynamic characteristics of power modules are significantly influenced by the parasitic parameters, especially parasitic inductance. Accordingly, more attention has been paid to measuring parasitic inductance extensively. However, the existing methods also have corresponding limitations, such as inadequate accuracy, complex measurement, and poor repeatability. Thus, a parasitic inductance extraction method for the arbitrary power flow path based on the parallel resonance principle is proposed in this paper. Compared with the methods proposed previously, the parasitic inductance can be extracted by only measuring the voltage of the parallel capacitor, which is a low-voltage and low-frequency damped oscillation attenuation signal. Finally, experimental results validate the effectiveness of the proposed method in measuring the parasitic inductance of the terminals of the silicon carbide power module.
{"title":"A Single-Event Parasitic Inductance Characterization Method Based on Parallel Resonance Principle for Power Modules","authors":"Hongchang Cui, Fengtao Yang, Hang Kong, Chenxu Zhao, Junhui Yang, Yang Nie, Feng Wang, Laili Wang, K. Gao","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213848","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213848","url":null,"abstract":"Dynamic characteristics of power modules are significantly influenced by the parasitic parameters, especially parasitic inductance. Accordingly, more attention has been paid to measuring parasitic inductance extensively. However, the existing methods also have corresponding limitations, such as inadequate accuracy, complex measurement, and poor repeatability. Thus, a parasitic inductance extraction method for the arbitrary power flow path based on the parallel resonance principle is proposed in this paper. Compared with the methods proposed previously, the parasitic inductance can be extracted by only measuring the voltage of the parallel capacitor, which is a low-voltage and low-frequency damped oscillation attenuation signal. Finally, experimental results validate the effectiveness of the proposed method in measuring the parasitic inductance of the terminals of the silicon carbide power module.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132068633","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213622
S. Pyo, Sang-Jung Lee, Dongsul Shin, Dea-Wook Kang, Jong-Pil Lee, Tae-Sik Park
This paper proposes the selection of modulation strategies Phase shift pulse width modulation (PS-PWM) Level shift pulse width modulation (LS-PWM) through Total Harmonic Distortion (THD) analysis of Modular Multi-level Converter (MMC) with Battery Energy Storage System (BESS) system. The MMC-BESS system is delta-connected to the grid through a transformer in parallel, and the MMC-BESS Submodule (SM) is an existing MMC full-bridge SM with a DC/DC converter and a battery. It is a STATCOM structure with a battery that can act as an ESS. The THD of the modulation strategies PS-PWM and LS-PWM were compared by selecting different MMC SM levels and switching frequencies. The THD analysis was performed using MATLAB, and the MMC-BESS simulation was verified using PSCAD.
{"title":"THD Analysis of Modular Multi-level Converter with BESS","authors":"S. Pyo, Sang-Jung Lee, Dongsul Shin, Dea-Wook Kang, Jong-Pil Lee, Tae-Sik Park","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213622","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213622","url":null,"abstract":"This paper proposes the selection of modulation strategies Phase shift pulse width modulation (PS-PWM) Level shift pulse width modulation (LS-PWM) through Total Harmonic Distortion (THD) analysis of Modular Multi-level Converter (MMC) with Battery Energy Storage System (BESS) system. The MMC-BESS system is delta-connected to the grid through a transformer in parallel, and the MMC-BESS Submodule (SM) is an existing MMC full-bridge SM with a DC/DC converter and a battery. It is a STATCOM structure with a battery that can act as an ESS. The THD of the modulation strategies PS-PWM and LS-PWM were compared by selecting different MMC SM levels and switching frequencies. The THD analysis was performed using MATLAB, and the MMC-BESS simulation was verified using PSCAD.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132323925","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213966
Anupam Nigam, Dong-Choon Lee
This paper proposes the uniqueness of LFT (line frequency transformer) structure in a QAB-CLLC-based MMC. The LVDC and MVAC sides of the SST (solid state transformer) are both powered through the LFT. In addition, the LFT has a leakage reactance of its own, thereby eliminating arm inductors used in the traditional MMC. The suggested topology can save manufacturing costs while increasing the system power density. Moreover, simulation results are shown to support the validity of the proposed topology. The conversion of 2 MW and 100 kW from MVDC to MVAC and LVDC, respectively, demonstrates the advantages of the novel topology over the conventional MMC.
{"title":"Replacement of Arm Inductors by Leakage Inductance of Input Transformers in QAB-CLLC-Based MMC","authors":"Anupam Nigam, Dong-Choon Lee","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213966","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213966","url":null,"abstract":"This paper proposes the uniqueness of LFT (line frequency transformer) structure in a QAB-CLLC-based MMC. The LVDC and MVAC sides of the SST (solid state transformer) are both powered through the LFT. In addition, the LFT has a leakage reactance of its own, thereby eliminating arm inductors used in the traditional MMC. The suggested topology can save manufacturing costs while increasing the system power density. Moreover, simulation results are shown to support the validity of the proposed topology. The conversion of 2 MW and 100 kW from MVDC to MVAC and LVDC, respectively, demonstrates the advantages of the novel topology over the conventional MMC.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130869634","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213851
T. Kosaka, C. Higashihama, T. Ishihara, H. Matsumori, N. Matsui
This paper presents design study on a lightweight quasi-coreless surface permanent magnet synchronous motor (SPMSM) employing Carbon Fiber Reinforced Plastics (CFRP) as the stator body to make it lighter. Stator body is composed of CFRP, a little soft magnetic composites core and aluminum winding for high power density. The design procedure for lightening the quasi-coreless SPMSM and experimental drive performance evaluation results are reported. Finally, remaining issues which have been founded are discussed.
{"title":"Design Study on Light-weight Quasi-coreless SPMSM using CFRP, Small Amount of SMC Core and Aluminum Winding","authors":"T. Kosaka, C. Higashihama, T. Ishihara, H. Matsumori, N. Matsui","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213851","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213851","url":null,"abstract":"This paper presents design study on a lightweight quasi-coreless surface permanent magnet synchronous motor (SPMSM) employing Carbon Fiber Reinforced Plastics (CFRP) as the stator body to make it lighter. Stator body is composed of CFRP, a little soft magnetic composites core and aluminum winding for high power density. The design procedure for lightening the quasi-coreless SPMSM and experimental drive performance evaluation results are reported. Finally, remaining issues which have been founded are discussed.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130245945","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213719
Debjit Rana, S. Mishra
Multiport converters are used to power more than one load using a single conversion stage. Many applications require galvanic isolation between the input and output of the converter. This paper presents a technique using which a boost and buck-boost topology can be transformed to a multiport converter with isolated outputs. The implementation starts with identification of terminals at which transformer can be interfaced for these topologies. Selection and characterization of circuit for implementation are defined. Some design expressions on selection of components for maximum power transfer are also defined. The proposed method is experimentally validated using lab prototypes.
{"title":"Derivation of Isolated Outputs from a Boost and Buck-Boost Topology","authors":"Debjit Rana, S. Mishra","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213719","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213719","url":null,"abstract":"Multiport converters are used to power more than one load using a single conversion stage. Many applications require galvanic isolation between the input and output of the converter. This paper presents a technique using which a boost and buck-boost topology can be transformed to a multiport converter with isolated outputs. The implementation starts with identification of terminals at which transformer can be interfaced for these topologies. Selection and characterization of circuit for implementation are defined. Some design expressions on selection of components for maximum power transfer are also defined. The proposed method is experimentally validated using lab prototypes.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130397431","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213709
Hong Feng, Hongyi Lin, Jiasheng Xu, Liang Wu, Guo-zhu Chen
A high-voltage (HV) generator with phase-shifting closed-loop control for X-ray is proposed. The LCC topology with input parallel output series (IPOS) is used in the circuit, and the phase-shifting closed-loop control is adopted to reduce the output voltage ripple further. In this paper, the LCC resonant converter is modeled based on fundamental harmonic approximation (FHA), and the output voltage ripple of a single module transformer is derived. On this basis, the output ripple of the multi-module LCC cascade converter is calculated and analyzed. Aiming at the problem that the ripple cancellation effect deteriorates due to the inconsistent parameters between modules, a phase locked loop (PLL) phase-shifting closed-loop control strategy is proposed. The simulation and experiment results show that the control method is feasible and reasonable.
{"title":"A Phase-shifting Control IPOS High-voltage Generator with Low Output Voltage Ripple for X-Ray","authors":"Hong Feng, Hongyi Lin, Jiasheng Xu, Liang Wu, Guo-zhu Chen","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213709","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213709","url":null,"abstract":"A high-voltage (HV) generator with phase-shifting closed-loop control for X-ray is proposed. The LCC topology with input parallel output series (IPOS) is used in the circuit, and the phase-shifting closed-loop control is adopted to reduce the output voltage ripple further. In this paper, the LCC resonant converter is modeled based on fundamental harmonic approximation (FHA), and the output voltage ripple of a single module transformer is derived. On this basis, the output ripple of the multi-module LCC cascade converter is calculated and analyzed. Aiming at the problem that the ripple cancellation effect deteriorates due to the inconsistent parameters between modules, a phase locked loop (PLL) phase-shifting closed-loop control strategy is proposed. The simulation and experiment results show that the control method is feasible and reasonable.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130484083","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213751
M. Sheraz, W. Choi
Lithium-ion batteries are gaining more attention in the rapidly growing industry of electrical vehicles (EVs). Moreover, a lot of efforts are put by the industry to reuse retired EVs batteries in energy storage systems (ESS). To achieve optimal performance of the repurposed xEVs batteries in ESS, they should be similar in characteristic such as capacity, State of Health (SOH) and Remaining Useful Life (RUL). This makes the battery grading techniques to play a crucial role in it. Ohmic resistance measurement is a convenient way to evaluate the battery aging. However, conventional Electrochemical Impedance Spectroscopy (EIS) methods to measure ohmic resistance require complex curve fitting procedures while some others conventional methods are not much accurate. This research proposes a high-speed technique to measure ohmic resistance directly without using these curve fitting procedures. A Combined Phased Multi-Sine (CPMS) excitation is used to perturb the battery in specific frequency band. The require perturbation time is just 1 sec and ohmic resistance is measured using two impedance values. This makes the proposed technique several times faster than conventional EIS methods. The accuracy is verified by performing experiments on three types of Li-ion batteries. The obtain results shows less than 0.15% difference with reference conventional EIS method. This technique is suitable for grading mass xEVs batteries by evaluating their aging.
{"title":"A High-Speed Measurement Technique for the Ohmic Resistance of Lithium-Ion Batteries","authors":"M. Sheraz, W. Choi","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213751","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213751","url":null,"abstract":"Lithium-ion batteries are gaining more attention in the rapidly growing industry of electrical vehicles (EVs). Moreover, a lot of efforts are put by the industry to reuse retired EVs batteries in energy storage systems (ESS). To achieve optimal performance of the repurposed xEVs batteries in ESS, they should be similar in characteristic such as capacity, State of Health (SOH) and Remaining Useful Life (RUL). This makes the battery grading techniques to play a crucial role in it. Ohmic resistance measurement is a convenient way to evaluate the battery aging. However, conventional Electrochemical Impedance Spectroscopy (EIS) methods to measure ohmic resistance require complex curve fitting procedures while some others conventional methods are not much accurate. This research proposes a high-speed technique to measure ohmic resistance directly without using these curve fitting procedures. A Combined Phased Multi-Sine (CPMS) excitation is used to perturb the battery in specific frequency band. The require perturbation time is just 1 sec and ohmic resistance is measured using two impedance values. This makes the proposed technique several times faster than conventional EIS methods. The accuracy is verified by performing experiments on three types of Li-ion batteries. The obtain results shows less than 0.15% difference with reference conventional EIS method. This technique is suitable for grading mass xEVs batteries by evaluating their aging.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131355301","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 : 2023-05-22DOI: 10.23919/ICPE2023-ECCEAsia54778.2023.10213584
Dae-Geun Jeong, Jongwook Park, Yohan Jang, Sungwoo Bae
Lithium iron phosphate batteries are currently popular in the electric vehicle market due to their high reliability and low price. However, due to the strong non-linearity of lithium iron phosphate open circuit voltage, it is difficult to estimate the state of charge with the traditional method. In this paper, a bidirectional long short-term memory model is used to accurately estimate the state-of-charge of a lithium iron phosphate battery in a usage environment such as an electric vehicle. A lithium iron phosphate battery charge/discharge test applying an electric vehicle driving cycle was preceded, and the state of charge estimation error was confirmed in the bidirectional long short-term memory model through the charge/discharge data. The mean absolute error of the bidirectional long short-term memory model was 1.80%, confirming the best performance among the deep learning models evaluated in this paper.
{"title":"State of Charge Estimation of Lithium Iron Phosphate Battery Using Bidirectional Long Short-Term Memory","authors":"Dae-Geun Jeong, Jongwook Park, Yohan Jang, Sungwoo Bae","doi":"10.23919/ICPE2023-ECCEAsia54778.2023.10213584","DOIUrl":"https://doi.org/10.23919/ICPE2023-ECCEAsia54778.2023.10213584","url":null,"abstract":"Lithium iron phosphate batteries are currently popular in the electric vehicle market due to their high reliability and low price. However, due to the strong non-linearity of lithium iron phosphate open circuit voltage, it is difficult to estimate the state of charge with the traditional method. In this paper, a bidirectional long short-term memory model is used to accurately estimate the state-of-charge of a lithium iron phosphate battery in a usage environment such as an electric vehicle. A lithium iron phosphate battery charge/discharge test applying an electric vehicle driving cycle was preceded, and the state of charge estimation error was confirmed in the bidirectional long short-term memory model through the charge/discharge data. The mean absolute error of the bidirectional long short-term memory model was 1.80%, confirming the best performance among the deep learning models evaluated in this paper.","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129216689","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 : 2023-05-22DOI: 10.23919/icpe2023-ecceasia54778.2023.10213734
{"title":"ICPE 2023 - ECCE Asia 2023 Breaker Page","authors":"","doi":"10.23919/icpe2023-ecceasia54778.2023.10213734","DOIUrl":"https://doi.org/10.23919/icpe2023-ecceasia54778.2023.10213734","url":null,"abstract":"","PeriodicalId":151155,"journal":{"name":"2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126738286","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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