Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9899863
I. Yusupov, D. Dobrykh, D. Filonov, A. Slobozhanyuk, P. Ginzburg
Radio Frequency Identification (RFID) is a widely used method for contactless data reading over a wireless communication channel [1] . RFID tags are widely used in warehouse logistics, payment systems, as biometric identifiers, and in many other applications. Using today’s technology, RFID tags can be implemented almost anywhere, and their electromagnetic design can be adapted to each application. In this paper, we present a new type of ceramic RFID tag. The general concept of the RFID tag is shown in Fig. 1(a) . The tag consists of a dielectric cylindrical resonator with a non-resonant metal split ring located on the surface. A commercial tag’s chip is placed in the gap. Using the reader’s interrogation signal, a resonator’s magnetic dipole mode is excited ( Fig. 1(b) ). The excited resonator displacement currents are converted into conduction current in the ring, initiating microchip operation. Due to the minimal amount of metal components, the proposed ceramic tag can show good performance on conductive surfaces.
{"title":"Compact ceramic on-metal RFID tag","authors":"I. Yusupov, D. Dobrykh, D. Filonov, A. Slobozhanyuk, P. Ginzburg","doi":"10.1109/APWC49427.2022.9899863","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9899863","url":null,"abstract":"Radio Frequency Identification (RFID) is a widely used method for contactless data reading over a wireless communication channel [1] . RFID tags are widely used in warehouse logistics, payment systems, as biometric identifiers, and in many other applications. Using today’s technology, RFID tags can be implemented almost anywhere, and their electromagnetic design can be adapted to each application. In this paper, we present a new type of ceramic RFID tag. The general concept of the RFID tag is shown in Fig. 1(a) . The tag consists of a dielectric cylindrical resonator with a non-resonant metal split ring located on the surface. A commercial tag’s chip is placed in the gap. Using the reader’s interrogation signal, a resonator’s magnetic dipole mode is excited ( Fig. 1(b) ). The excited resonator displacement currents are converted into conduction current in the ring, initiating microchip operation. Due to the minimal amount of metal components, the proposed ceramic tag can show good performance on conductive surfaces.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122546500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9899942
Yang-Lie Zhang, Yoshihiro Toda
Artificial material is a good coordinator for RF applications because its customizable permittivity provides a freedom of design for the RF devices. Additionally, miniaturization or thin configuration of the devices can be realized by using an artificial material with a high-value permittivity. An artificial material made of multilayer printed circuit board (PCB) for patch antenna gain enhancement has been proposed by our group [1] . This paper proposes an artificial material made of single layer PCB configuration for antenna gain enhancement.
{"title":"An Artificial Material with Single Layer Configuration for Antenna Gain Enhancement","authors":"Yang-Lie Zhang, Yoshihiro Toda","doi":"10.1109/APWC49427.2022.9899942","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9899942","url":null,"abstract":"Artificial material is a good coordinator for RF applications because its customizable permittivity provides a freedom of design for the RF devices. Additionally, miniaturization or thin configuration of the devices can be realized by using an artificial material with a high-value permittivity. An artificial material made of multilayer printed circuit board (PCB) for patch antenna gain enhancement has been proposed by our group [1] . This paper proposes an artificial material made of single layer PCB configuration for antenna gain enhancement.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124100760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9899922
T. Walpita, A. Eroglu, M. N. Mahmoud
An accurate RF power detection is highly desirable for wide range of RF applications [1] . The major error in measurement of high-power RF signal detection occurs due to non-linearities and system dynamics [2] . The error also varies based on the operational frequency because of the frequency dependency and non-linear characteristics of active devices [3] . One of the methods to improve the measurement error is to minimize the error by applying conventional control system at each discrete frequency. This requires power calibration of the RF system for large number of discrete frequencies which is not practical within the entire operational frequency bandwidth.
{"title":"High Power RF Calibration Method with Artificial Intelligence","authors":"T. Walpita, A. Eroglu, M. N. Mahmoud","doi":"10.1109/APWC49427.2022.9899922","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9899922","url":null,"abstract":"An accurate RF power detection is highly desirable for wide range of RF applications [1] . The major error in measurement of high-power RF signal detection occurs due to non-linearities and system dynamics [2] . The error also varies based on the operational frequency because of the frequency dependency and non-linear characteristics of active devices [3] . One of the methods to improve the measurement error is to minimize the error by applying conventional control system at each discrete frequency. This requires power calibration of the RF system for large number of discrete frequencies which is not practical within the entire operational frequency bandwidth.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131736454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9899984
Bing Xiao, H. Wong
The Internet of Things (IoT) develops rapidly at present and in the foreseeable future. A fast-increasing number of devices are being connected wirelessly. This connectivity is provided by different wireless technologies operating at different frequencies. Thus, future wireless smart devices should have the ability of massive IoT connections, and their antennas need to cover multiple frequency bands. This paper introduces two novel methods for linear-shaped multi-band dipole antennas for small wireless smart devices, such as strip- or bar-shaped AR/VR smart glasses, smart wristbands, smartwatches, smart pencils. The analysis is based on the theory of characteristic modes. First, we know a classic dipole antenna resonates only at odd modes, limiting the design of multiple frequency bands. Thus, a novel feeding structure is introduced to excite both odd and even modes of a dipole antenna simultaneously. A flexible method is also introduced to pick out and tune specific mode(s) among them. Second, we introduce an algorithm to calculate the fewest arms required by a multi-arm linear dipole antenna. By these two novel techniques, antenna designers could realize multi-band antenna more easily on narrow surfaces.
{"title":"Multi-band Dipole Antenna by Multi-mode Excitation for Massive Connections of IoT","authors":"Bing Xiao, H. Wong","doi":"10.1109/APWC49427.2022.9899984","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9899984","url":null,"abstract":"The Internet of Things (IoT) develops rapidly at present and in the foreseeable future. A fast-increasing number of devices are being connected wirelessly. This connectivity is provided by different wireless technologies operating at different frequencies. Thus, future wireless smart devices should have the ability of massive IoT connections, and their antennas need to cover multiple frequency bands. This paper introduces two novel methods for linear-shaped multi-band dipole antennas for small wireless smart devices, such as strip- or bar-shaped AR/VR smart glasses, smart wristbands, smartwatches, smart pencils. The analysis is based on the theory of characteristic modes. First, we know a classic dipole antenna resonates only at odd modes, limiting the design of multiple frequency bands. Thus, a novel feeding structure is introduced to excite both odd and even modes of a dipole antenna simultaneously. A flexible method is also introduced to pick out and tune specific mode(s) among them. Second, we introduce an algorithm to calculate the fewest arms required by a multi-arm linear dipole antenna. By these two novel techniques, antenna designers could realize multi-band antenna more easily on narrow surfaces.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129375941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9900020
Paul Tcheg, D. Pouhè
The unidirectional radiation of spiral antennas mounted on a substrate requires the presence of a ground plane. In this work, we successively illustrate the impact of dielectric material and ground plane on the key metrics of a planar equiangular spiral antenna (PESA). For this purpose, a PESA mounted on several substrates with different dielectric properties and thicknesses is modeled and simulated. We introduce the tertiary current flowing on spiral arms when backed by a ground plane.
{"title":"On the Influence of Ground and Substrate on the Radiation Characteristics of Planar Spiral Antennas","authors":"Paul Tcheg, D. Pouhè","doi":"10.1109/APWC49427.2022.9900020","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9900020","url":null,"abstract":"The unidirectional radiation of spiral antennas mounted on a substrate requires the presence of a ground plane. In this work, we successively illustrate the impact of dielectric material and ground plane on the key metrics of a planar equiangular spiral antenna (PESA). For this purpose, a PESA mounted on several substrates with different dielectric properties and thicknesses is modeled and simulated. We introduce the tertiary current flowing on spiral arms when backed by a ground plane.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130563656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9900007
Keisuke Sato, I. Oshima, H. Nakano
This paper presents a stair-shaped dielectric rod antenna, which is a simplified version of the conventional tapered rod antenna. The operation frequency is set to be 28 GHz for 5G communications. The antenna configuration is composed of three sections: a transition section from a rectangular waveguide to a circular waveguide, a horn exciter section, and a stair-shaped dielectric rod section. The number of stairs is chosen to be three. The analysis shows that the optimized rod radius and length realize a high gain of more than 22 dBi. The 3-dB beam width is approximately 15°. The VSWR is less than 2 across a frequency range of 26.5 GHz to 32 GHz.
{"title":"Rod Antenna for 28-GHz Band Operation","authors":"Keisuke Sato, I. Oshima, H. Nakano","doi":"10.1109/APWC49427.2022.9900007","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9900007","url":null,"abstract":"This paper presents a stair-shaped dielectric rod antenna, which is a simplified version of the conventional tapered rod antenna. The operation frequency is set to be 28 GHz for 5G communications. The antenna configuration is composed of three sections: a transition section from a rectangular waveguide to a circular waveguide, a horn exciter section, and a stair-shaped dielectric rod section. The number of stairs is chosen to be three. The analysis shows that the optimized rod radius and length realize a high gain of more than 22 dBi. The 3-dB beam width is approximately 15°. The VSWR is less than 2 across a frequency range of 26.5 GHz to 32 GHz.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114264919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9899885
Keisuke Fujita
The radiation characteristics of spherical helix antennas (SHAs) such as the Q factor and the radiation efficiency were analyzed by both numerical [1] and analytical [2] method such as the vector spherical harmonics (VSH). The VSH enables one to derive theoretical results. However, previous study with the VSH were restricted to the current distribution of the lowest TM and/or TE modes on the whole spherical surface. The effect of the higher-order modes was, thus, ignored in the conventional theoretical model. In this summary, the significance of the higher-order modes is demonstrated by calculating the near-electric field of the SHA with the VSH.
{"title":"Significance of the Higher-order Modes to the Near-field Calculation of the Spherical Helix Antennas","authors":"Keisuke Fujita","doi":"10.1109/APWC49427.2022.9899885","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9899885","url":null,"abstract":"The radiation characteristics of spherical helix antennas (SHAs) such as the Q factor and the radiation efficiency were analyzed by both numerical [1] and analytical [2] method such as the vector spherical harmonics (VSH). The VSH enables one to derive theoretical results. However, previous study with the VSH were restricted to the current distribution of the lowest TM and/or TE modes on the whole spherical surface. The effect of the higher-order modes was, thus, ignored in the conventional theoretical model. In this summary, the significance of the higher-order modes is demonstrated by calculating the near-electric field of the SHA with the VSH.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127391669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9900040
J. J. Arnez, Maria G. Lima Damasceno, Renata K. Gomes Do Reis, Leandro Almeida Da Silva, Lucas Beltrão Cavalcante Tribuzy, Mateus C. Lucena
The eCall (emergency Call) service is already widely used by 3G networks, however with the 4G/LTE network’s evolution, it is natural for a service migration to this more efficient architecture. For migration to take place correctly, there are three important steps to be followed: source code development that allows the eCall call to use the IMS (IP-Multimedia Subsystem) network nodes on mobile devices; an existing PSAP (Public-Safety Answering Point) with packet based connectivity and the validation through battery of tests using a 4G/LTE mobile network setup. The purpose of this article is to analyze and describe an eCall flow in a real time testbed using both the IMS and the 4G/LTE mobile networks. In addition, the development of source code to allow emergency services and laboratory testbeds were done. Furthermore, based on TS 23.167 standard, this scientific paper presents procedures needed to provide the eCall service by performing bench testing for different categories of emergency numbers and demonstrating the importance of stable operation between IMS network nodes and the LTE/4G core network.
{"title":"Analysis of emergency call tracking in a 4G/LTE mobile network","authors":"J. J. Arnez, Maria G. Lima Damasceno, Renata K. Gomes Do Reis, Leandro Almeida Da Silva, Lucas Beltrão Cavalcante Tribuzy, Mateus C. Lucena","doi":"10.1109/APWC49427.2022.9900040","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9900040","url":null,"abstract":"The eCall (emergency Call) service is already widely used by 3G networks, however with the 4G/LTE network’s evolution, it is natural for a service migration to this more efficient architecture. For migration to take place correctly, there are three important steps to be followed: source code development that allows the eCall call to use the IMS (IP-Multimedia Subsystem) network nodes on mobile devices; an existing PSAP (Public-Safety Answering Point) with packet based connectivity and the validation through battery of tests using a 4G/LTE mobile network setup. The purpose of this article is to analyze and describe an eCall flow in a real time testbed using both the IMS and the 4G/LTE mobile networks. In addition, the development of source code to allow emergency services and laboratory testbeds were done. Furthermore, based on TS 23.167 standard, this scientific paper presents procedures needed to provide the eCall service by performing bench testing for different categories of emergency numbers and demonstrating the importance of stable operation between IMS network nodes and the LTE/4G core network.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130319016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9899957
H. Nakano, T. Abe, J. Yamauchi
A metaloop antenna (MLA) has open space within its loop. This paper investigates the placement of electronic components within this space. For this, the components are generalized by a square conducting plate of perimeter length PSQR. The antenna characteristics for the MLA, for which perimeter length PMLA is larger than λ0, are evaluated by changing PSQR, where λ0 is the free space wavelength at the operating frequency. It is found that an MLA of PMLA = 1λg (with λg being the guided wavelength of the current on the loop) continues radiating a broadside beam of circular polarization until the conducting plate and the MLA are in close proximity.
{"title":"Metaloop Antenna with a Conducting Plate","authors":"H. Nakano, T. Abe, J. Yamauchi","doi":"10.1109/APWC49427.2022.9899957","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9899957","url":null,"abstract":"A metaloop antenna (MLA) has open space within its loop. This paper investigates the placement of electronic components within this space. For this, the components are generalized by a square conducting plate of perimeter length P<inf>SQR</inf>. The antenna characteristics for the MLA, for which perimeter length P<inf>MLA</inf> is larger than λ<inf>0</inf>, are evaluated by changing P<inf>SQR</inf>, where λ<inf>0</inf> is the free space wavelength at the operating frequency. It is found that an MLA of P<inf>MLA</inf> = 1λ<inf>g</inf> (with λ<inf>g</inf> being the guided wavelength of the current on the loop) continues radiating a broadside beam of circular polarization until the conducting plate and the MLA are in close proximity.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124038016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.1109/APWC49427.2022.9899965
M. Tanabe
A spiral antenna with a circular high-impedance surface (HIS) reflector (CirHISR) sandwiched by ring-shaped absorbers (R-ABSs) is investigated. To improve the variation of the gain in a specific frequency region for a spiral antenna with a CirHISR, we propose a new structure where the CirHISR is sandwiched by two R-ABSs. The antenna height is 0.096 wavelength at 2.5 GHz (the lowest operating frequency). The antenna characteristics are analyzed using a commercially available method of moment software. It is found that the CirHISR sandwiched by two R-ABSs contributes to the enhancement of the gain variation (more than 5.0 dBi across a frequency range of 2.5 GHz to 9 GHz), compared to the gain of the CirHISR without R-ABSs. Other antenna characteristics, including input impedance and axial ratio, are also analyzed and presented here.
{"title":"Spiral Antenna with a Circular HIS Reflector Sandwiched by Ring-shaped Absorbers","authors":"M. Tanabe","doi":"10.1109/APWC49427.2022.9899965","DOIUrl":"https://doi.org/10.1109/APWC49427.2022.9899965","url":null,"abstract":"A spiral antenna with a circular high-impedance surface (HIS) reflector (CirHISR) sandwiched by ring-shaped absorbers (R-ABSs) is investigated. To improve the variation of the gain in a specific frequency region for a spiral antenna with a CirHISR, we propose a new structure where the CirHISR is sandwiched by two R-ABSs. The antenna height is 0.096 wavelength at 2.5 GHz (the lowest operating frequency). The antenna characteristics are analyzed using a commercially available method of moment software. It is found that the CirHISR sandwiched by two R-ABSs contributes to the enhancement of the gain variation (more than 5.0 dBi across a frequency range of 2.5 GHz to 9 GHz), compared to the gain of the CirHISR without R-ABSs. Other antenna characteristics, including input impedance and axial ratio, are also analyzed and presented here.","PeriodicalId":422168,"journal":{"name":"2022 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125133728","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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