Pub Date : 2016-05-17DOI: 10.1109/APEMC.2016.7522998
Li Junchuan, Wang Jingqin, L. Yanan, C. Yulong, Fan Haoliang, Li Huijun
This paper proposes a new complex resonant topology of wireless power transfer system, which still get better transmission performance in far distance. First, the circuit structure is theoretical analyzed based on LCL type complex resonant topology in the receiver, the reflective impedance, the load power and transmission efficiency and other expressions are deduced. The simulation model is constructed by MATLAB and compared with traditional series resonant structure. Simulation and experimental data show that the proposed structure improves the quality factor Q value and the transmission efficiency can reach more than eighty percent which up to ninety-five percent at low degree of coupling coefficient, and reduces the current flowing through the switch more than fifty percent in order to achieve the lower conduction loss; in the case of long-range and low coupling coefficient, get better transmission performance.
{"title":"The study based on new resonant topology of wireless power transfer system","authors":"Li Junchuan, Wang Jingqin, L. Yanan, C. Yulong, Fan Haoliang, Li Huijun","doi":"10.1109/APEMC.2016.7522998","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522998","url":null,"abstract":"This paper proposes a new complex resonant topology of wireless power transfer system, which still get better transmission performance in far distance. First, the circuit structure is theoretical analyzed based on LCL type complex resonant topology in the receiver, the reflective impedance, the load power and transmission efficiency and other expressions are deduced. The simulation model is constructed by MATLAB and compared with traditional series resonant structure. Simulation and experimental data show that the proposed structure improves the quality factor Q value and the transmission efficiency can reach more than eighty percent which up to ninety-five percent at low degree of coupling coefficient, and reduces the current flowing through the switch more than fifty percent in order to achieve the lower conduction loss; in the case of long-range and low coupling coefficient, get better transmission performance.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123528766","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522719
Zhang Tong, Xie Shuguo
Electrical field sensors are widely used for detecting transient signal in the EMC tests. The traditional method to detect the electrical field sensor signal is single-path detection using spectrum analyzer, which is applicable when the frequency is known. But if the signal is transient during the EMC tests, it often needs to sweep multiple times to detect different frequency points, or test multiple times to get the field at different locations. In this paper, a new method is proposed innovatively for detecting the electrical field sensor signal with wideband signal detection circuit. This circuit consists of a wideband low noise amplifier module and a wideband peak detector module. By using a wideband LNA module, this circuit can achieve high sensitivity detection. And by using a wideband peak detector module, it can realize simultaneous detection of wideband signals. The detailed design of the two modules is shown in this paper. After simulation and testing, it`s proved that the two modules could reach the established targets, and the wideband signal detection circuit can be used for the detection of wideband electrical field sensor signal in EMC tests.
{"title":"Design of a wideband signal detection circuit for electrical field sensor","authors":"Zhang Tong, Xie Shuguo","doi":"10.1109/APEMC.2016.7522719","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522719","url":null,"abstract":"Electrical field sensors are widely used for detecting transient signal in the EMC tests. The traditional method to detect the electrical field sensor signal is single-path detection using spectrum analyzer, which is applicable when the frequency is known. But if the signal is transient during the EMC tests, it often needs to sweep multiple times to detect different frequency points, or test multiple times to get the field at different locations. In this paper, a new method is proposed innovatively for detecting the electrical field sensor signal with wideband signal detection circuit. This circuit consists of a wideband low noise amplifier module and a wideband peak detector module. By using a wideband LNA module, this circuit can achieve high sensitivity detection. And by using a wideband peak detector module, it can realize simultaneous detection of wideband signals. The detailed design of the two modules is shown in this paper. After simulation and testing, it`s proved that the two modules could reach the established targets, and the wideband signal detection circuit can be used for the detection of wideband electrical field sensor signal in EMC tests.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121636760","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522834
Hongcai Chen, Zilong Qin, Y. Du, Qinghai Wang, Yu Ding
This paper presents a Partial Element Equivalent Circuit (PEEC) based simulation tool, called TAES for simulating transients in a wire system. The enhancement in the traditional PEEC model with the vector fitting method is provided in order to achieve a time domain simulation for frequency-dependent conductors. A system with steel bars, cables and arrestors is studied and results of experimental verification are provided. Finally, a practical configuration of telecommunication tower is analyzed using proposed tool.
{"title":"TAES: A PEEC-based tool for transient simulation","authors":"Hongcai Chen, Zilong Qin, Y. Du, Qinghai Wang, Yu Ding","doi":"10.1109/APEMC.2016.7522834","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522834","url":null,"abstract":"This paper presents a Partial Element Equivalent Circuit (PEEC) based simulation tool, called TAES for simulating transients in a wire system. The enhancement in the traditional PEEC model with the vector fitting method is provided in order to achieve a time domain simulation for frequency-dependent conductors. A system with steel bars, cables and arrestors is studied and results of experimental verification are provided. Finally, a practical configuration of telecommunication tower is analyzed using proposed tool.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122003288","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522982
Huan Zhang, Shuo Wang, J. Puukko
Recently, transformerless photovoltaic (PV) systems become popular in industrial applications due to the demands of high efficiency and low cost inverters. However, the leakage ground current and common mode (CM) electromagnetic interference (EMI) noise becomes significant so they need to be addressed. In solving the problems, a simple CM noise model is widely used. However, the model does not include information on how the noise source will be influenced by modulation schemes and how the propagation path will affect the CM noise spectrum. This paper intends to improve the model. A complete CM noise modeling and prediction method is proposed for the three-phase three-level inverter. Modeling process starts from building a simple CM noise model for the inverter and is then improved by two steps. Step one is for CM noise source modeling and the step two is for noise propagation path modeling. For noise source modeling, the influence of two different modulation schemes on the generation of CM noise is discussed and simulation results are illustrated. For the noise path modeling, scattering parameters is used for parasitic parameter extraction. A circuit model for the prediction of the CM noise spectrum is then developed and an inverter prototype is built for the experimental verification of the proposed technique. The proposed modeling and prediction technique is validated by the comparison between the measured and the simulated CM EMI noise spectra.
{"title":"Common mode EMI noise modeling and prediction for a three-phase, three-level, grid tied photovoltaic inverter","authors":"Huan Zhang, Shuo Wang, J. Puukko","doi":"10.1109/APEMC.2016.7522982","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522982","url":null,"abstract":"Recently, transformerless photovoltaic (PV) systems become popular in industrial applications due to the demands of high efficiency and low cost inverters. However, the leakage ground current and common mode (CM) electromagnetic interference (EMI) noise becomes significant so they need to be addressed. In solving the problems, a simple CM noise model is widely used. However, the model does not include information on how the noise source will be influenced by modulation schemes and how the propagation path will affect the CM noise spectrum. This paper intends to improve the model. A complete CM noise modeling and prediction method is proposed for the three-phase three-level inverter. Modeling process starts from building a simple CM noise model for the inverter and is then improved by two steps. Step one is for CM noise source modeling and the step two is for noise propagation path modeling. For noise source modeling, the influence of two different modulation schemes on the generation of CM noise is discussed and simulation results are illustrated. For the noise path modeling, scattering parameters is used for parasitic parameter extraction. A circuit model for the prediction of the CM noise spectrum is then developed and an inverter prototype is built for the experimental verification of the proposed technique. The proposed modeling and prediction technique is validated by the comparison between the measured and the simulated CM EMI noise spectra.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121064653","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522899
B. Zhu, Hong Li, Zhichang Yang
Chaotic pulse width modulation (CPWM) is applied widely in power converters to suppress electromagnetic interference (EMI). However, core loss analysis of magnetic components in power converters under CPWM is usually overlooked. In this paper, a core loss analysis approach of inductor in a buck converter under CPWM is introduced based on ANSYS. This approach can be applied to predict and compare inductor core loss in buck converter under CPWM and traditional pulse width modulation (TPWM). The core loss analysis results show that the proposed approach is appropriate for predicting the core loss of buck converter inductor under CPWM.
{"title":"Core loss analysis of buck converter under chaotic PWM based on ANSYS","authors":"B. Zhu, Hong Li, Zhichang Yang","doi":"10.1109/APEMC.2016.7522899","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522899","url":null,"abstract":"Chaotic pulse width modulation (CPWM) is applied widely in power converters to suppress electromagnetic interference (EMI). However, core loss analysis of magnetic components in power converters under CPWM is usually overlooked. In this paper, a core loss analysis approach of inductor in a buck converter under CPWM is introduced based on ANSYS. This approach can be applied to predict and compare inductor core loss in buck converter under CPWM and traditional pulse width modulation (TPWM). The core loss analysis results show that the proposed approach is appropriate for predicting the core loss of buck converter inductor under CPWM.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125712502","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522957
Man-tang Su, Jia-qing Chen, Yu Zhang, Jie Yang
Based on the scattering model of charged particles to electromagnetic waves in Rayleigh approximation and permittivity model of ice particles, we deduced the attenuation model under the situation when the electromagnetic waves pass through ice particles area, then we performed the simulation and made analyses. The results show that: (1) When the ice particles are electrically charged, the attenuation of electromagnetic waves is much greater than those who are not charged. (2) The more charge of ice particles, the greater effect it will make on the attenuation of electromagnetic waves. (3) The frequency of the electromagnetic waves also has a great influence on the attenuation, the higher the frequency, the greater the attenuation.
{"title":"The influence of ice particles on microwave propagation in thundercloud","authors":"Man-tang Su, Jia-qing Chen, Yu Zhang, Jie Yang","doi":"10.1109/APEMC.2016.7522957","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522957","url":null,"abstract":"Based on the scattering model of charged particles to electromagnetic waves in Rayleigh approximation and permittivity model of ice particles, we deduced the attenuation model under the situation when the electromagnetic waves pass through ice particles area, then we performed the simulation and made analyses. The results show that: (1) When the ice particles are electrically charged, the attenuation of electromagnetic waves is much greater than those who are not charged. (2) The more charge of ice particles, the greater effect it will make on the attenuation of electromagnetic waves. (3) The frequency of the electromagnetic waves also has a great influence on the attenuation, the higher the frequency, the greater the attenuation.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128014612","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522881
Zhao Chunying, Yan Liping, Zhao Xiang, H. Ka-ma
The length determination rule of two equivalent lines in asymptotic approach for high-frequency field coupling to transmission lines is investigated. The induced current along transmission lines with different structure exposed to high frequency plane wave is calculated using asymptotic approach and full-wave analysis commercial software NEC respectively. Results show that the length of two equivalent lines recommended in literature sometimes leads to incorrect results. Length determination rule of equivalent lines is suggested according to induced current results obtained using different length of equivalent lines.
{"title":"Length determination of equivalent lines in asymptotic approach for high-frequency field coupling to transmission lines","authors":"Zhao Chunying, Yan Liping, Zhao Xiang, H. Ka-ma","doi":"10.1109/APEMC.2016.7522881","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522881","url":null,"abstract":"The length determination rule of two equivalent lines in asymptotic approach for high-frequency field coupling to transmission lines is investigated. The induced current along transmission lines with different structure exposed to high frequency plane wave is calculated using asymptotic approach and full-wave analysis commercial software NEC respectively. Results show that the length of two equivalent lines recommended in literature sometimes leads to incorrect results. Length determination rule of equivalent lines is suggested according to induced current results obtained using different length of equivalent lines.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128019131","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522798
Lu Wang, Hongxing Zheng
A tri-band antenna has been designed for the satellite communication devices. It is constructed as a U-shaped slot put into the middle of the patch, and two L-shaped slot patterns around the edge, accompanied with 4 circular corners on the patch. Three frequency bands can be achieved in the range of 4.63 GHz-6.55 GHz, 8.34 GHz- 9.59GHz, and 12.34 GHz-13.79GHz. Current distribution has been analyzed on each slot size. It is found that return loss has been reduced effectively in required frequencies when increasing the length of current path properly. In addition, reducing the width of ground, the whole size of antenna can be decreased, and its radiation effectiveness can be enhanced. Measurement results show the antenna available.
{"title":"Tri-band antenna with slot patterns on the edge","authors":"Lu Wang, Hongxing Zheng","doi":"10.1109/APEMC.2016.7522798","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522798","url":null,"abstract":"A tri-band antenna has been designed for the satellite communication devices. It is constructed as a U-shaped slot put into the middle of the patch, and two L-shaped slot patterns around the edge, accompanied with 4 circular corners on the patch. Three frequency bands can be achieved in the range of 4.63 GHz-6.55 GHz, 8.34 GHz- 9.59GHz, and 12.34 GHz-13.79GHz. Current distribution has been analyzed on each slot size. It is found that return loss has been reduced effectively in required frequencies when increasing the length of current path properly. In addition, reducing the width of ground, the whole size of antenna can be decreased, and its radiation effectiveness can be enhanced. Measurement results show the antenna available.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124959352","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522964
Jun Dong, Lina Hong, Jie Meng
Aiming at the shortcomings of the existing composite electromagnetic field calculation method, the paper puts forward a kind of composite field estimate method based on Element filed decomposition-superposition. Equivalent modeling was carried out on the antenna radiator and its platform use the way of decomposition - superposition. Different features model according to the different electromagnetic calculation method. And then, using the method, it forecast the electromagnetic fields between multiple platforms, and designs the process to predict. It meets the requirement of test electromagnetic environment (EME) prediction for multi-platform. It makes up for the deficiency of the existing electromagnetic environment forecast methods, and is conducive to solve the multiple electrically large platform composite field calculation problems.
{"title":"Composite electromagnetic field estimation method based on element field decomposition and superposition","authors":"Jun Dong, Lina Hong, Jie Meng","doi":"10.1109/APEMC.2016.7522964","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522964","url":null,"abstract":"Aiming at the shortcomings of the existing composite electromagnetic field calculation method, the paper puts forward a kind of composite field estimate method based on Element filed decomposition-superposition. Equivalent modeling was carried out on the antenna radiator and its platform use the way of decomposition - superposition. Different features model according to the different electromagnetic calculation method. And then, using the method, it forecast the electromagnetic fields between multiple platforms, and designs the process to predict. It meets the requirement of test electromagnetic environment (EME) prediction for multi-platform. It makes up for the deficiency of the existing electromagnetic environment forecast methods, and is conducive to solve the multiple electrically large platform composite field calculation problems.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"01 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130599683","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 : 2016-05-17DOI: 10.1109/APEMC.2016.7522749
Ren Hongna, Z. Xiaoying, Zhong Heng, Song Yuning, Wang Zifan
To study the effect of natural lightning shapes on electromagnetic spectrum characteristics, a new method leading to the law of lightning electromagnetic spectrum characteristics is put forward. Firstly, generate 3-D lightning channel models randomly with different shapes by setting different parameters of dielectric breakdown model. Then, add excitation, namely double-exponential lightning current. Lastly, calculate the characteristics of time-varying electric field spectrum using finite difference time domain (FDTD) method. Research shows that fractal dimension has great influence on spectrum characteristics of lightning leader. The degree of influences of probability exponent on the lightning spectrum characteristics is more than that of internal electric field of the channel while critical electric field threshold is the least. Results show that there is an obviously linear correlation between probability exponent and lightning spectrum peak value. Some useful conclusions have been drawn from the research, which will be reference for lightning simulation, especially for the spectrum research.
{"title":"Effect of different lightning shapes on electromagnetic spectrum characteristics","authors":"Ren Hongna, Z. Xiaoying, Zhong Heng, Song Yuning, Wang Zifan","doi":"10.1109/APEMC.2016.7522749","DOIUrl":"https://doi.org/10.1109/APEMC.2016.7522749","url":null,"abstract":"To study the effect of natural lightning shapes on electromagnetic spectrum characteristics, a new method leading to the law of lightning electromagnetic spectrum characteristics is put forward. Firstly, generate 3-D lightning channel models randomly with different shapes by setting different parameters of dielectric breakdown model. Then, add excitation, namely double-exponential lightning current. Lastly, calculate the characteristics of time-varying electric field spectrum using finite difference time domain (FDTD) method. Research shows that fractal dimension has great influence on spectrum characteristics of lightning leader. The degree of influences of probability exponent on the lightning spectrum characteristics is more than that of internal electric field of the channel while critical electric field threshold is the least. Results show that there is an obviously linear correlation between probability exponent and lightning spectrum peak value. Some useful conclusions have been drawn from the research, which will be reference for lightning simulation, especially for the spectrum research.","PeriodicalId":358257,"journal":{"name":"2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115928944","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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