Pub Date : 2021-11-28DOI: 10.1109/iwem53379.2021.9790531
Kaiyu Wang, Shining Sun, Hanyu Xie, Bian Wu
A low-profile filtering antenna with a wide stopband based on substrate integrated waveguide (SIW) is presented in this article. First, a five-pole bandpass filter using a cul-de-sac topology scheme with two finite-transmission zeros (FTZs) is proposed. The SIW filter which consists of three single-mode cavities using TE101 mode and a dual-mode cavity using TE201 and TE103 mode achieves a wide stopband due to the suppression of TE102, TE202, and TE104 mode. Then a cavity-backed slot antenna is designed so that its bandwidth is narrower than that of the filter, thus making it behave as a last-order resonator. With a center frequency of 10 GHz and a fractional bandwidth of 4.03%, the antenna has good stopband performance and achieves a gain of 7.8 dB in terms of a flat gain profile.
{"title":"Low-Profile Filtering Antenna With Wide Stopband Using Dual-Mode Rectangular SIW Cavities","authors":"Kaiyu Wang, Shining Sun, Hanyu Xie, Bian Wu","doi":"10.1109/iwem53379.2021.9790531","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790531","url":null,"abstract":"A low-profile filtering antenna with a wide stopband based on substrate integrated waveguide (SIW) is presented in this article. First, a five-pole bandpass filter using a cul-de-sac topology scheme with two finite-transmission zeros (FTZs) is proposed. The SIW filter which consists of three single-mode cavities using TE101 mode and a dual-mode cavity using TE201 and TE103 mode achieves a wide stopband due to the suppression of TE102, TE202, and TE104 mode. Then a cavity-backed slot antenna is designed so that its bandwidth is narrower than that of the filter, thus making it behave as a last-order resonator. With a center frequency of 10 GHz and a fractional bandwidth of 4.03%, the antenna has good stopband performance and achieves a gain of 7.8 dB in terms of a flat gain profile.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"52 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":"128730837","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/iwem53379.2021.9790644
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/iwem53379.2021.9790649
Dongliang Zhang, Qi Wu
A dual-band microstrip patch antenna is proposed. The fractional bandwidths for the two bands are 2% and 4%, respectively. The antenna is evolved from a circular patch antenna. Two groups of concentrical conductive vias are used to generate new resonances and increase the resonance depth. Several key parameters of the antenna are studied, which shows that the proposed method is a general solution suitable to make the proposed antenna works in different frequency bands.
{"title":"A Dual-band Low-profile Circular Patch Antenna","authors":"Dongliang Zhang, Qi Wu","doi":"10.1109/iwem53379.2021.9790649","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790649","url":null,"abstract":"A dual-band microstrip patch antenna is proposed. The fractional bandwidths for the two bands are 2% and 4%, respectively. The antenna is evolved from a circular patch antenna. Two groups of concentrical conductive vias are used to generate new resonances and increase the resonance depth. Several key parameters of the antenna are studied, which shows that the proposed method is a general solution suitable to make the proposed antenna works in different frequency bands.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"18 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":"127259309","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/iWEM53379.2021.9790601
Li Yang, Qi Ming He, Zhuo Chen, Shan Xu, Jun Zhang
The interconnection loss between the radio frequency (RF) front-end and the antenna become prominent for system integration in the millimeter-wave (mm-wave) band, and joint design is required at the device level. Because of the higher propagation loss in the mm-wave band, the cost for communication coverage will increase sharply. This is the main impetus for the development of filtering antenna with low cost and low interconnection loss. In this paper, through the aperture sharing and mode hybridization, three adjacent modes are sequentially excited to achieve broadband characteristics. The simulation impedance bandwidth of the antenna is 24.1~28.4 GHz with a relative bandwidth of 16.4% and the peak realized gain is 5.7dBi. Radiation null can be realized at the edge of the passband with an increased coupling path between the slot and U-shaped ring, hence producing a more than 20dB out-of-band suppression.
{"title":"Multi-Mode Wideband Filtering Antenna for 5G Millimeter-Wave Communication","authors":"Li Yang, Qi Ming He, Zhuo Chen, Shan Xu, Jun Zhang","doi":"10.1109/iWEM53379.2021.9790601","DOIUrl":"https://doi.org/10.1109/iWEM53379.2021.9790601","url":null,"abstract":"The interconnection loss between the radio frequency (RF) front-end and the antenna become prominent for system integration in the millimeter-wave (mm-wave) band, and joint design is required at the device level. Because of the higher propagation loss in the mm-wave band, the cost for communication coverage will increase sharply. This is the main impetus for the development of filtering antenna with low cost and low interconnection loss. In this paper, through the aperture sharing and mode hybridization, three adjacent modes are sequentially excited to achieve broadband characteristics. The simulation impedance bandwidth of the antenna is 24.1~28.4 GHz with a relative bandwidth of 16.4% and the peak realized gain is 5.7dBi. Radiation null can be realized at the edge of the passband with an increased coupling path between the slot and U-shaped ring, hence producing a more than 20dB out-of-band suppression.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"46 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":"126482262","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/iwem53379.2021.9790408
Sun Ruofei
This paper presented a design method of active Butterworth high-pass filter (HPF) with flat pass-band gain. This method, based on the transformation of domain surfaces, used correspondence in Butterworth filter’s denominator polynomials and the response function of Sallen-Key circuit to derive the formulas of Sallen Key HPF expressed by Butterworth filter’s quality factor Qi, it was verified by LTspice software simulation. The paper gave a 6th active high-pass filter whose corner frequency was 100Hz, gain of 4.5dB in pass-band and stop-band attenuation -30db @50Hz. The simulation result was agreed with requirements well, the method and formulas of Butterworth active HPF are reasonable.
{"title":"A Design Method of Active High-Pass Butter-worth Filter","authors":"Sun Ruofei","doi":"10.1109/iwem53379.2021.9790408","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790408","url":null,"abstract":"This paper presented a design method of active Butterworth high-pass filter (HPF) with flat pass-band gain. This method, based on the transformation of domain surfaces, used correspondence in Butterworth filter’s denominator polynomials and the response function of Sallen-Key circuit to derive the formulas of Sallen Key HPF expressed by Butterworth filter’s quality factor Qi, it was verified by LTspice software simulation. The paper gave a 6th active high-pass filter whose corner frequency was 100Hz, gain of 4.5dB in pass-band and stop-band attenuation -30db @50Hz. The simulation result was agreed with requirements well, the method and formulas of Butterworth active HPF are reasonable.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"32 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":"127776070","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/iWEM53379.2021.9790482
Z. X. Yang, W. Chan, L. H. Zhou, X. Zhou
This paper introduces an analytical design method for the generalized Class-E power amplifier (PA) with shunt filter at any duty ratio. The idealized switch waveforms are derived first, and then the optimal parameter values of load network are obtained, and three important indicators the peak switch drain voltage, power output capability and maximum operating frequency at different sets of values are also investigated. To verify the effectiveness of the design method, a simulation experiment is demonstrated showing waveforms matching well with theory.
{"title":"Generalized Class-E Power Amplifier with Shunt Filter at Any Duty Ratio","authors":"Z. X. Yang, W. Chan, L. H. Zhou, X. Zhou","doi":"10.1109/iWEM53379.2021.9790482","DOIUrl":"https://doi.org/10.1109/iWEM53379.2021.9790482","url":null,"abstract":"This paper introduces an analytical design method for the generalized Class-E power amplifier (PA) with shunt filter at any duty ratio. The idealized switch waveforms are derived first, and then the optimal parameter values of load network are obtained, and three important indicators the peak switch drain voltage, power output capability and maximum operating frequency at different sets of values are also investigated. To verify the effectiveness of the design method, a simulation experiment is demonstrated showing waveforms matching well with theory.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"168 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":"127388164","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/iwem53379.2021.9790458
J. Xiao, Xiangling Liu, Xiao-Fang Li
In this report, a multi-layer suspended SCPW MIMO filternna with adjustable gain zeros on both sides of the passband is proposed, which works at 5.21GHz with an isolation of no less than 25.3dB, a return loss of no less than 15dB, a gain of 2.8dBi, and an envelope correlation coefficient of 0.002, these performance have been demonstrated by simulation and some experimental results. Surface waves and space waves can be suppressed by the proposed suspended coplanar waveguide structure and copper separating wall, respectively.
{"title":"Four-port MIMO Filtenna Based on Multi-layer Suspended Coplanar Waveguide","authors":"J. Xiao, Xiangling Liu, Xiao-Fang Li","doi":"10.1109/iwem53379.2021.9790458","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790458","url":null,"abstract":"In this report, a multi-layer suspended SCPW MIMO filternna with adjustable gain zeros on both sides of the passband is proposed, which works at 5.21GHz with an isolation of no less than 25.3dB, a return loss of no less than 15dB, a gain of 2.8dBi, and an envelope correlation coefficient of 0.002, these performance have been demonstrated by simulation and some experimental results. Surface waves and space waves can be suppressed by the proposed suspended coplanar waveguide structure and copper separating wall, respectively.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"74 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":"127484105","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/iwem53379.2021.9790435
Wenlei Wang, H. Jin, G. Luo
Substrate integrated waveguide (SIW) cavity-backed structure, as a multi-mode resonator featuring low loss and low profile, is suitable for the implementation of circularly polarized (CP) antennas. By embedding CP patches into SIW cavities, radiation nulls can be generated by the modes of SIW cavity and the mixed electric and magnetic coupling between the patch and the SIW cavity, simultaneously, to form filtering responses. By adopting these filtering mechanisms, three examples of SIW cavity-backed filtennas are proposed and studied. A wideband single-layer dual-CP SIW cavity-backed patch filtenna with an out-of-band rejection level over 13 dB is achieved. The radiation nulls are realized by the TE110 mode of the SIW cavity and the mixed coupling between the patch and the cavity. Then modified perturbations are used in our second work to reduce the frequency of TE220 mode of the SIW cavity to improve the high-band side roll-off characteristics. What’s more, four filtering slots are asymmetrically introduced to introduce extra radiation null to achieve a high rejection level of 21 dB extend to 1.5f0. As no additional filtering circuits are used in the filtenna element, a novel 2 × 2 SR filtenna array with wide AR bandwidth of 18% and rejection level up to 33 dB is achieved. At last, a millimeter-wave 4 × 4 SR filtenna array based on higher-order SIW cavity modes is developed. The modified TE410 mode and TE330 mode cooperating with four embedded patches are used to form a 2 × 2 subarray. Four 2 × 2 subarrays combined with a filtering 2 × 2 SR feeding network are used to realize a 4 × 4 SR filtenna array with compact feeding network and good filtering performance.
{"title":"Researches on Circularly-Polarized SIW Cavity-Backed Filtennas","authors":"Wenlei Wang, H. Jin, G. Luo","doi":"10.1109/iwem53379.2021.9790435","DOIUrl":"https://doi.org/10.1109/iwem53379.2021.9790435","url":null,"abstract":"Substrate integrated waveguide (SIW) cavity-backed structure, as a multi-mode resonator featuring low loss and low profile, is suitable for the implementation of circularly polarized (CP) antennas. By embedding CP patches into SIW cavities, radiation nulls can be generated by the modes of SIW cavity and the mixed electric and magnetic coupling between the patch and the SIW cavity, simultaneously, to form filtering responses. By adopting these filtering mechanisms, three examples of SIW cavity-backed filtennas are proposed and studied. A wideband single-layer dual-CP SIW cavity-backed patch filtenna with an out-of-band rejection level over 13 dB is achieved. The radiation nulls are realized by the TE110 mode of the SIW cavity and the mixed coupling between the patch and the cavity. Then modified perturbations are used in our second work to reduce the frequency of TE220 mode of the SIW cavity to improve the high-band side roll-off characteristics. What’s more, four filtering slots are asymmetrically introduced to introduce extra radiation null to achieve a high rejection level of 21 dB extend to 1.5f0. As no additional filtering circuits are used in the filtenna element, a novel 2 × 2 SR filtenna array with wide AR bandwidth of 18% and rejection level up to 33 dB is achieved. At last, a millimeter-wave 4 × 4 SR filtenna array based on higher-order SIW cavity modes is developed. The modified TE410 mode and TE330 mode cooperating with four embedded patches are used to form a 2 × 2 subarray. Four 2 × 2 subarrays combined with a filtering 2 × 2 SR feeding network are used to realize a 4 × 4 SR filtenna array with compact feeding network and good filtering performance.","PeriodicalId":141204,"journal":{"name":"2021 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM)","volume":"14 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":"132372336","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/iwem53379.2021.9790583
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}
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