Pub Date : 2021-11-28DOI: 10.1109/iwem53379.2021.9790583
Ying Wang, Yazhou Dong, Shiwei Dong, Xumin Yu, Xiaojun Li
This paper presents a design method to improve the power-added efficiency and output power of microwave power amplifier(PA) by introducing a feedback resonant network between the gate-drain of the transistor, leading to the impedance increase of the internal drain-to-gate feedback branch, decrease power loss of the internal of the transistor, and increasing the power flow to the load while the total generated power remains the same, thus increasing the output power and power-added efficiency of the PA. Besides, the method of circuit stability and performance optimization design is studied to ensure the amplifier performance while taking into account the stability factor measurement and eliminating the instability in the matching network design process.
{"title":"High-Efficiency Power Amplifier for Microwave Power Transmission System","authors":"Ying Wang, Yazhou Dong, Shiwei Dong, Xumin Yu, Xiaojun Li","doi":"10.1109/iwem53379.2021.9790583","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790583","url":null,"abstract":"This paper presents a design method to improve the power-added efficiency and output power of microwave power amplifier(PA) by introducing a feedback resonant network between the gate-drain of the transistor, leading to the impedance increase of the internal drain-to-gate feedback branch, decrease power loss of the internal of the transistor, and increasing the power flow to the load while the total generated power remains the same, thus increasing the output power and power-added efficiency of the PA. Besides, the method of circuit stability and performance optimization design is studied to ensure the amplifier performance while taking into account the stability factor measurement and eliminating the instability in the matching network design process.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132800024","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 : 2021-11-28DOI: 10.1109/iwem53379.2021.9790593
Xiao-dong Cheng, Zihao Chen
An H-shape slot coupled automotive radar microstrip comb array antenna is proposed in this paper. The designed antenna has the advantages of low profile, low cost and easy integration with RF chips. In order to miniaturize the size and verify the applicability of the proposed antenna for automotive radar applications, one 1×5 array is designed at 77-GHz. The simulation results show that the -10 dB input impedance bandwidth covers the 77-GHz band and the maximal peak realized gain is 10.14 dB at 77 GHz. In addition, compared with the traditional series fed microstrip rectangular patch array antenna, the comb array antenna has more compact structure.
{"title":"77GHz Comb Array Antenna Based on FOWLP for Automotive Radar Applications","authors":"Xiao-dong Cheng, Zihao Chen","doi":"10.1109/iwem53379.2021.9790593","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790593","url":null,"abstract":"An H-shape slot coupled automotive radar microstrip comb array antenna is proposed in this paper. The designed antenna has the advantages of low profile, low cost and easy integration with RF chips. In order to miniaturize the size and verify the applicability of the proposed antenna for automotive radar applications, one 1×5 array is designed at 77-GHz. The simulation results show that the -10 dB input impedance bandwidth covers the 77-GHz band and the maximal peak realized gain is 10.14 dB at 77 GHz. In addition, compared with the traditional series fed microstrip rectangular patch array antenna, the comb array antenna has more compact structure.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116591455","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 unique 3D-printing quasi-ellipsoidal dielectric lens antenna with high gain is proposed in this work for Ka-band application. For proof of concept, the quasi-ellipsoidal dielectric lens antenna consists of a waveguide and dielectric lens (DL). The DL consists of a hemisphere and a spherical cap with the same size of contacting plane as the hemisphere, which has different permittivity of 2.9 and 3.9, respectively. The simulation results show that the designed lens antenna not only has excellent electrical performance with an average |S11| < -14 dB in the bandwidth of 26-30 GHz, but also has the merit of greatly improving antenna gain. The quasi-ellipsoidal DL with a long axis of 50 mm and a short axis of 42 mm can increase the gain of the waveguide from 6.7 dBi to about 20 dBi.
{"title":"A 3D-Printing Quasi-Ellipsoidal Lens Antenna","authors":"Zi-Yu Pang, Xiao-Yu Ma, Xing-Quan Zhuo, Cheng-Yu Wang, Sheng-Sen You, Guanhua Huang","doi":"10.1109/iwem53379.2021.9790397","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790397","url":null,"abstract":"A unique 3D-printing quasi-ellipsoidal dielectric lens antenna with high gain is proposed in this work for Ka-band application. For proof of concept, the quasi-ellipsoidal dielectric lens antenna consists of a waveguide and dielectric lens (DL). The DL consists of a hemisphere and a spherical cap with the same size of contacting plane as the hemisphere, which has different permittivity of 2.9 and 3.9, respectively. The simulation results show that the designed lens antenna not only has excellent electrical performance with an average |S11| < -14 dB in the bandwidth of 26-30 GHz, but also has the merit of greatly improving antenna gain. The quasi-ellipsoidal DL with a long axis of 50 mm and a short axis of 42 mm can increase the gain of the waveguide from 6.7 dBi to about 20 dBi.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116970791","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 : 2021-11-28DOI: 10.1109/iwem53379.2021.9790644
Ling Chen, Yizhao Wang, Xiaodong Ye, Hao Wang, S. Tao
In the paper, radar cross section (RCS) reduction method for slot-loaded UAV based on characteristic mode theory (CMT) is proposed. Firstly, the strong characteristic current distribution positions of UAVs in different modes are obtained through characteristic mode analysis (CMA). Then, the slot-loaded technology is carried out on the overlapping position to achieve the purpose of RCS reduction of UAV. The experimental results show that RCS is reduced in different incident directions of plane waves. UAV can achieve RCS reduction with the peak of 8dBsm within 2~3 GHz. The proposed method can provide a new design idea for stealth technology of UAV.
{"title":"Radar Cross Section Reduction for Slot-loaded UAV Based on Characteristic Mode Theory","authors":"Ling Chen, Yizhao Wang, Xiaodong Ye, Hao Wang, S. Tao","doi":"10.1109/iwem53379.2021.9790644","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790644","url":null,"abstract":"In the paper, radar cross section (RCS) reduction method for slot-loaded UAV based on characteristic mode theory (CMT) is proposed. Firstly, the strong characteristic current distribution positions of UAVs in different modes are obtained through characteristic mode analysis (CMA). Then, the slot-loaded technology is carried out on the overlapping position to achieve the purpose of RCS reduction of UAV. The experimental results show that RCS is reduced in different incident directions of plane waves. UAV can achieve RCS reduction with the peak of 8dBsm within 2~3 GHz. The proposed method can provide a new design idea for stealth technology of UAV.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116510418","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 : 2021-11-28DOI: 10.1109/iwem53379.2021.9790505
Hao Sun, Yuxin Ren, Xiaolong Liu, Ying Zhu
Plane wave generator (PWG) is a phased array system that can create a plane wave in the quiet zone (QZ). By setting a number of appropriate complex weights on PWG elements, wireless devices can be measured at a shorter distance. However, for the 5G millimeter-wave frequency range, the PWG system confronts many new challenges due to high operating frequency and huge bandwidth. In this paper, the plane wave synthesis is discussed from the point view of sparse representation, and a novel orthogonal match pursuit algorithm has been proposed for PWG design. Moreover, plenty of simulation works have been performed in this paper. The simulation results show that the proposed algorithm can synthesize the QZ over a wide frequency range with limited excited PWG sources.
{"title":"Design and Simulation for 5G Millimeter-wave Plane Wave Generator","authors":"Hao Sun, Yuxin Ren, Xiaolong Liu, Ying Zhu","doi":"10.1109/iwem53379.2021.9790505","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790505","url":null,"abstract":"Plane wave generator (PWG) is a phased array system that can create a plane wave in the quiet zone (QZ). By setting a number of appropriate complex weights on PWG elements, wireless devices can be measured at a shorter distance. However, for the 5G millimeter-wave frequency range, the PWG system confronts many new challenges due to high operating frequency and huge bandwidth. In this paper, the plane wave synthesis is discussed from the point view of sparse representation, and a novel orthogonal match pursuit algorithm has been proposed for PWG design. Moreover, plenty of simulation works have been performed in this paper. The simulation results show that the proposed algorithm can synthesize the QZ over a wide frequency range with limited excited PWG sources.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116708986","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 : 2021-11-28DOI: 10.1109/iwem53379.2021.9790494
Chuanwei Ding, Jiaming Yan, Hong Hong, Xiaohua Zhu
Due to the aging population, fall detection is crucial for elderly health care and assisted living. Radar-based methods attract much attention for its potential for high accuracy, robustness, and privacy preservation. In this paper, sparsity-based feature extraction methods are proposed to extract robust time-Doppler features with physical meanings for the classification of fall and fall-similar motions. First, sparse representation theory is introduced and through Gabor-based sparse dictionary, sparse representation of the received signals can be achieved in time-Doppler domain. Then, corresponding sparse point maps consisting of a series of sparse solutions are obtained by OMP-based algorithm. Particularly, reconstructed signals can be utilized to demonstrate that sparse features preserve most information from original ones while ignoring noise interferences. Finally, experiments have been conducted to show its feasibility by achieving an average accuracy of 95% on fall detection.
{"title":"Sparsity-based Feature Extraction in Fall Detection with a Portable FMCW Radar","authors":"Chuanwei Ding, Jiaming Yan, Hong Hong, Xiaohua Zhu","doi":"10.1109/iwem53379.2021.9790494","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790494","url":null,"abstract":"Due to the aging population, fall detection is crucial for elderly health care and assisted living. Radar-based methods attract much attention for its potential for high accuracy, robustness, and privacy preservation. In this paper, sparsity-based feature extraction methods are proposed to extract robust time-Doppler features with physical meanings for the classification of fall and fall-similar motions. First, sparse representation theory is introduced and through Gabor-based sparse dictionary, sparse representation of the received signals can be achieved in time-Doppler domain. Then, corresponding sparse point maps consisting of a series of sparse solutions are obtained by OMP-based algorithm. Particularly, reconstructed signals can be utilized to demonstrate that sparse features preserve most information from original ones while ignoring noise interferences. Finally, experiments have been conducted to show its feasibility by achieving an average accuracy of 95% on fall detection.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124524750","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 : 2021-11-28DOI: 10.1109/iwem53379.2021.9790521
Heng-hua Cao, Jianing Cao, Q. Ren
The coating of radar absorbing material can reduce radar cross section of aircrafts significantly, it’s indeed necessary to analyze their electromagnetic scattering characteristics. The traditional method requires plenty of time thus can’t meet the need of real-time analysis. To solve this problem, this paper proposed an image-to-image deep neural network based on U-net with residual unit. This network can predict the ISAR image for a coated target with random defect. The well-trained network can accelerate the speed by five orders while ensuring a relative error lower than 0.28%. The numerical results are exhibited to prove that the proposed method is of great efficiency and accuracy compared to the traditional method.
{"title":"A Method to Obtain Deep Neural Network for Predicting ISAR Images of Coted Targets with Defect","authors":"Heng-hua Cao, Jianing Cao, Q. Ren","doi":"10.1109/iwem53379.2021.9790521","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790521","url":null,"abstract":"The coating of radar absorbing material can reduce radar cross section of aircrafts significantly, it’s indeed necessary to analyze their electromagnetic scattering characteristics. The traditional method requires plenty of time thus can’t meet the need of real-time analysis. To solve this problem, this paper proposed an image-to-image deep neural network based on U-net with residual unit. This network can predict the ISAR image for a coated target with random defect. The well-trained network can accelerate the speed by five orders while ensuring a relative error lower than 0.28%. The numerical results are exhibited to prove that the proposed method is of great efficiency and accuracy compared to the traditional method.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124010649","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 : 2021-11-28DOI: 10.1109/iwem53379.2021.9790372
Jingtao Zeng, Kun Huang, Shi-wo Ta
This paper presents the design of a miniaturized low-pass filter embedded in LTCC (low-temperature co-fired ceramic) substrate. A low-pass filter used in wireless communication system with 9500 MHz cut-off frequency and 3dB insertion loss was designed based on LC resonator components. The simulation result shows that the attenuation is more than 30 dB in the stopband and the insertion loss in the passband is about 3dB . The size of the filter is 3.2mm X 1.6mm X 0.95mm. A basic guidelines is shown for the design. A sixth-order filter is fabricated for verification.
本文介绍了一种嵌入低温共烧陶瓷衬底的小型化低通滤波器的设计。基于LC谐振元件设计了一种截止频率为9500 MHz、插入损耗为3dB的无线通信低通滤波器。仿真结果表明，阻带内的衰减大于30 dB，通带内的插入损耗约为3dB。过滤器尺寸为3.2mm X 1.6mm X 0.95mm。给出了设计的基本准则。制作了一个六阶滤波器进行验证。
{"title":"A LC Resonator Based Low-pass Filter Embedded in LTCC Substrate","authors":"Jingtao Zeng, Kun Huang, Shi-wo Ta","doi":"10.1109/iwem53379.2021.9790372","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790372","url":null,"abstract":"This paper presents the design of a miniaturized low-pass filter embedded in LTCC (low-temperature co-fired ceramic) substrate. A low-pass filter used in wireless communication system with 9500 MHz cut-off frequency and 3dB insertion loss was designed based on LC resonator components. The simulation result shows that the attenuation is more than 30 dB in the stopband and the insertion loss in the passband is about 3dB . The size of the filter is 3.2mm X 1.6mm X 0.95mm. A basic guidelines is shown for the design. A sixth-order filter is fabricated for verification.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"170 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123846706","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 : 2021-11-28DOI: 10.1109/iwem53379.2021.9790495
Zhaoneng Jiang, Zhiwei Li, Liyin Nie, Yang Zheng, Ye Jiang, Feibiao Dong, Yankong Zhang
In this paper, a new type of reflective metasurface element with low profile is proposed. The simulation results show that the element has a reflection phase shift of 425 degrees at 10 GHz with the change of size, which meets the requirement of 360 degrees phase shift. Two types of reflective metasurface with vortex wave are designed by using this element. The mode numbers of the two reflective metasurfaces are l=+1 and l=+2, respectively. Simulation results show that the phase shift above the two metasurface are 2π and 4π respectively. Overall dimension of the antenna is 201.5 mm × 201.5mm × 3.5mm.
{"title":"A Low Profile Reflective Metasurface Element for Generating Vortex Wave","authors":"Zhaoneng Jiang, Zhiwei Li, Liyin Nie, Yang Zheng, Ye Jiang, Feibiao Dong, Yankong Zhang","doi":"10.1109/iwem53379.2021.9790495","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790495","url":null,"abstract":"In this paper, a new type of reflective metasurface element with low profile is proposed. The simulation results show that the element has a reflection phase shift of 425 degrees at 10 GHz with the change of size, which meets the requirement of 360 degrees phase shift. Two types of reflective metasurface with vortex wave are designed by using this element. The mode numbers of the two reflective metasurfaces are l=+1 and l=+2, respectively. Simulation results show that the phase shift above the two metasurface are 2π and 4π respectively. Overall dimension of the antenna is 201.5 mm × 201.5mm × 3.5mm.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"251 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122327616","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 : 2021-11-28DOI: 10.1109/iWEM53379.2021.9790393
Buyun Wang, S. Yan
This work proposes a six-polarized antenna by using 3 pairs of orthogonal dipoles and loops collocated at the same physical centers, and the size of the proposed antenna is 30 × 30 × 30 cm3, i.e., (0.52λ0)3. The coupling between the dipoles and the loops can be reduced by rotating their orientations in the 3D space. The simulated results show that the proposed antenna operates at 5.2 GHz with a bandwidth of 300 MHz, and all the values of the port coupling are lower than -13.6 dB. The gain are higher than 2.9 dBi, and 2 dBi for the dipoles and the loops, respectively. The radiation efficiencies are higher than 91%. The envelope correlation coefficients (ECCs) are lower than 0.08, and the degree of freedom (DOF) is 5.75, which can provide a good diversity performance and a high channel capacity in the wireless communication systems.
{"title":"A Six-polarized Antenna With Dipoles and Loops","authors":"Buyun Wang, S. Yan","doi":"10.1109/iWEM53379.2021.9790393","DOIUrl":"https://doi.org/10.1109/iWEM53379.2021.9790393","url":null,"abstract":"This work proposes a six-polarized antenna by using 3 pairs of orthogonal dipoles and loops collocated at the same physical centers, and the size of the proposed antenna is 30 × 30 × 30 cm3, i.e., (0.52λ0)3. The coupling between the dipoles and the loops can be reduced by rotating their orientations in the 3D space. The simulated results show that the proposed antenna operates at 5.2 GHz with a bandwidth of 300 MHz, and all the values of the port coupling are lower than -13.6 dB. The gain are higher than 2.9 dBi, and 2 dBi for the dipoles and the loops, respectively. The radiation efficiencies are higher than 91%. The envelope correlation coefficients (ECCs) are lower than 0.08, and the degree of freedom (DOF) is 5.75, which can provide a good diversity performance and a high channel capacity in the wireless communication systems.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128467846","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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