Pub Date : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021863
Zhuwen Zhou, Chen Lu, Zhou Lu
This article from the multiple frequencies capacitively coupled discharge in terms of the new method, provide a theoretical reference for the plasma simulation etching and a certain processing reference for semiconductor production. It is recommended that the percentage matching of voltage/frequency (400 V/6.0 MHz, 100 V/13.56 MHz, 200 V/27.0 MHz) be used. It is found that the occurrence of multiple peaks of ion density is approximately corresponding to the the integer period of high frequency. The peak time of ion kinetic energy appears nearby the low frequency period or nearby the low frequency half period. The results show that the time of ion density peak is controlled by the high frequency period and the time of ion average kinetic energy peak is controlled by the low frequency period.
{"title":"Multi-frequencies Capacitively Coupled Discharge Simulation","authors":"Zhuwen Zhou, Chen Lu, Zhou Lu","doi":"10.1109/PIERS-Fall48861.2019.9021863","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021863","url":null,"abstract":"This article from the multiple frequencies capacitively coupled discharge in terms of the new method, provide a theoretical reference for the plasma simulation etching and a certain processing reference for semiconductor production. It is recommended that the percentage matching of voltage/frequency (400 V/6.0 MHz, 100 V/13.56 MHz, 200 V/27.0 MHz) be used. It is found that the occurrence of multiple peaks of ion density is approximately corresponding to the the integer period of high frequency. The peak time of ion kinetic energy appears nearby the low frequency period or nearby the low frequency half period. The results show that the time of ion density peak is controlled by the high frequency period and the time of ion average kinetic energy peak is controlled by the low frequency period.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114997921","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021320
T. Nagayama, Shuntaro Uchida, S. Fukushima, Toshio Watanabe
We extend the theory of equivalent circuit models for two-dimensional (2-D) full-tensor anisotropic electromagnetic metamaterials and introduce the design method with equivalent circuit models to designs of 2-D full-tensor anisotropic acoustic metamaterials. Relations of circuit parameters and material parameters including the off-diagonal components of the mass density tensor are revealed from the duality of circuit equations and acoustic equations. A 2D acoustic carpet cloak for hiding a bump on a flat surface is designed with equivalent circuit models to confirm the validity of the theory. Circuit simulations are carried out and the voltage distributions and the radar cross sections are compared with those for the cases with the flat surface and the bump. Those results show the angle independent cloaking operations of the designed acoustic carpet cloak.
{"title":"Equivalent Circuit Models for Two-dimensional Full-tensor Anisotropic Acoustic Metamaterials","authors":"T. Nagayama, Shuntaro Uchida, S. Fukushima, Toshio Watanabe","doi":"10.1109/PIERS-Fall48861.2019.9021320","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021320","url":null,"abstract":"We extend the theory of equivalent circuit models for two-dimensional (2-D) full-tensor anisotropic electromagnetic metamaterials and introduce the design method with equivalent circuit models to designs of 2-D full-tensor anisotropic acoustic metamaterials. Relations of circuit parameters and material parameters including the off-diagonal components of the mass density tensor are revealed from the duality of circuit equations and acoustic equations. A 2D acoustic carpet cloak for hiding a bump on a flat surface is designed with equivalent circuit models to confirm the validity of the theory. Circuit simulations are carried out and the voltage distributions and the radar cross sections are compared with those for the cases with the flat surface and the bump. Those results show the angle independent cloaking operations of the designed acoustic carpet cloak.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115310457","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021903
Sanchith Padmaraj, K. Patil, Shaolin Liao
In this paper we have designed and simulated a compact and efficient dual-band WiFi energy harvester working at both the 2.5 GHz low-frequency band and the 5 GHz high-frequency band. The WiFi RF signal received by the dual-band patch antenna first. Then, the WiFi RF signal is fed to the full-wave rectifier, which converts it to a DC voltage. After that, a dual-path step-up boost converter increases the DC voltage to a target output voltage of 5 V. In addition, matching circuits are designed to achieve the optimal output power. Finally, during the demonstrating Pspice simulation, the WiFi RF signal received by the antenna is 100 mV, providing a 180 mV DC voltage after the rectifier and the target output voltage of 5 V after the boost converter.
{"title":"A Compact Dual-band WiFi Energy Harvester","authors":"Sanchith Padmaraj, K. Patil, Shaolin Liao","doi":"10.1109/PIERS-Fall48861.2019.9021903","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021903","url":null,"abstract":"In this paper we have designed and simulated a compact and efficient dual-band WiFi energy harvester working at both the 2.5 GHz low-frequency band and the 5 GHz high-frequency band. The WiFi RF signal received by the dual-band patch antenna first. Then, the WiFi RF signal is fed to the full-wave rectifier, which converts it to a DC voltage. After that, a dual-path step-up boost converter increases the DC voltage to a target output voltage of 5 V. In addition, matching circuits are designed to achieve the optimal output power. Finally, during the demonstrating Pspice simulation, the WiFi RF signal received by the antenna is 100 mV, providing a 180 mV DC voltage after the rectifier and the target output voltage of 5 V after the boost converter.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115625219","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021897
Yue Li, Peiqin Liu, Zhijun Zhang
In this paper, omnidirectional dual-polarized antennas are proposed with 3D structure. Magnetic currents are utilized to realize omnidirectional horizontal polarization in space-limited applications. By combining the magnetic current with folded slot and monopole antenna, two omnidirectional dual-polarized antennas are designed and fabricated. Both antennas have small volume 3D structures, which are quite suitable for space-limited and low wind drag applications.
{"title":"Omnidirectional Dual-polarized Antenna for Space-limited Systems","authors":"Yue Li, Peiqin Liu, Zhijun Zhang","doi":"10.1109/PIERS-Fall48861.2019.9021897","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021897","url":null,"abstract":"In this paper, omnidirectional dual-polarized antennas are proposed with 3D structure. Magnetic currents are utilized to realize omnidirectional horizontal polarization in space-limited applications. By combining the magnetic current with folded slot and monopole antenna, two omnidirectional dual-polarized antennas are designed and fabricated. Both antennas have small volume 3D structures, which are quite suitable for space-limited and low wind drag applications.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115692376","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021633
Sudhakar V. Alapati, Jagadeesh Dokuparthi
In this paper, a dual-band miniaturized Quarter Mode Substrate Integrated Waveguide (QMSIW) slot antenna is presented using fundamental mode (TE100) and hybrid mode (TE130,310). Initially, a full mode square cavity resonator is designed on a single substrate and divided into two halves along a magnetic wall to obtain a Half Mode SIW (HMSIW). This HMSIW is further divided into two parts along a magnetic wall to obtain Quarter Mode SIW (QMSIW). The QMSIW is loaded by two metallized vias and a slot and excited by line feeding technique. Since the antenna is radiating through two magnetic walls, the direction of maximum gain deviates from the boresight direction. The impedance bandwidth of the proposed antenna is 2.3% and 4.7% with peak gain of 5.3 dB and 8.7 dB at the center frequencies of 4.3 GHz and 9.6 GHz respectively.
{"title":"Metallized via Loaded Quarter Mode SIW Slot Antenna for Dual-band Operation","authors":"Sudhakar V. Alapati, Jagadeesh Dokuparthi","doi":"10.1109/PIERS-Fall48861.2019.9021633","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021633","url":null,"abstract":"In this paper, a dual-band miniaturized Quarter Mode Substrate Integrated Waveguide (QMSIW) slot antenna is presented using fundamental mode (TE100) and hybrid mode (TE130,310). Initially, a full mode square cavity resonator is designed on a single substrate and divided into two halves along a magnetic wall to obtain a Half Mode SIW (HMSIW). This HMSIW is further divided into two parts along a magnetic wall to obtain Quarter Mode SIW (QMSIW). The QMSIW is loaded by two metallized vias and a slot and excited by line feeding technique. Since the antenna is radiating through two magnetic walls, the direction of maximum gain deviates from the boresight direction. The impedance bandwidth of the proposed antenna is 2.3% and 4.7% with peak gain of 5.3 dB and 8.7 dB at the center frequencies of 4.3 GHz and 9.6 GHz respectively.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115730113","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021400
Yun Jing Zhang, Peng Li, Hao Zeng, Mei Song Tong
In this paper, a modified rectangular loop UHF RFID tag antenna mountable on metallic objects is proposed. We first investigate the impedance and gain of an electrically large loop antenna with and without a metal plate attached to its bottom, and give a typical loop tag antenna mountable on metal with a good performance. Based on the above analysis, a scheme of folding is presented to miniaturize the tag. In addition, utilizing the shorted ends formed by folding can tune the bandwidth to satisfy the global use. The total size is 70 mm × 34 mm × 1.6 mm. The measured maximum reading range is 3.5 m and 2.0 m among 902-928 MHz on metallic objects and in free space, respectively.
{"title":"Design of a Tunable UHF RFID Tag Based on Rectangular Loop Antennas for Metallic Objects","authors":"Yun Jing Zhang, Peng Li, Hao Zeng, Mei Song Tong","doi":"10.1109/PIERS-Fall48861.2019.9021400","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021400","url":null,"abstract":"In this paper, a modified rectangular loop UHF RFID tag antenna mountable on metallic objects is proposed. We first investigate the impedance and gain of an electrically large loop antenna with and without a metal plate attached to its bottom, and give a typical loop tag antenna mountable on metal with a good performance. Based on the above analysis, a scheme of folding is presented to miniaturize the tag. In addition, utilizing the shorted ends formed by folding can tune the bandwidth to satisfy the global use. The total size is 70 mm × 34 mm × 1.6 mm. The measured maximum reading range is 3.5 m and 2.0 m among 902-928 MHz on metallic objects and in free space, respectively.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124419325","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021547
Yang Liu, Kefei Liao
In the image-based radar cross-section (RCS) measurement system, wide-band transmitter and receiver are complex and expensive. To overcome this problem, this paper proposes a new method of frequency-sparse 3-D imaging. By increasing frequency interval, the number of sweep points is reduced. An improved 3-D back project (BP) algorithm is presented to obtain the image of targets, finally, the RCS of targets can be calculated. Simulation results show that this method is effective when the number of sweep points is adequate.
{"title":"RCS Measurement Based on Frequency-sparse 3-D Imaging","authors":"Yang Liu, Kefei Liao","doi":"10.1109/PIERS-Fall48861.2019.9021547","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021547","url":null,"abstract":"In the image-based radar cross-section (RCS) measurement system, wide-band transmitter and receiver are complex and expensive. To overcome this problem, this paper proposes a new method of frequency-sparse 3-D imaging. By increasing frequency interval, the number of sweep points is reduced. An improved 3-D back project (BP) algorithm is presented to obtain the image of targets, finally, the RCS of targets can be calculated. Simulation results show that this method is effective when the number of sweep points is adequate.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116980504","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021804
D. Wu, T. Yamaguchi, S. Inoue, S. Ohnuki
Parallel computing techniques play an important role in computational electromagnetics for performing fast and efficient simulation. In conventional techniques, the entire space is divided into many smaller parts whose computational loads are distributed into cluster. This paper reports a novel parallel technique, i.e., a time-division algorithm. In our method, EM field in frequency-domain is obtained by the finite-difference complex-frequency-domain (FDCFD) method. The field in the complex-frequency-domain is transformed into the time domain by fast inverse Laplace transform (FILT). The advantage of the proposed technique is that we can efficiently obtain the response at required observation time by parallel computing. As a numerical example of applications, a plasmonic waveguide array (PWA) using metallic slabs is designed for quantum walk toward developing quantum information technology. Properties of PWA will be discussed in comparison with classical random walk.
{"title":"Time-division Efficient Parallel Algorithm for Designing Metallic Slabs for Quantum Walk","authors":"D. Wu, T. Yamaguchi, S. Inoue, S. Ohnuki","doi":"10.1109/PIERS-Fall48861.2019.9021804","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021804","url":null,"abstract":"Parallel computing techniques play an important role in computational electromagnetics for performing fast and efficient simulation. In conventional techniques, the entire space is divided into many smaller parts whose computational loads are distributed into cluster. This paper reports a novel parallel technique, i.e., a time-division algorithm. In our method, EM field in frequency-domain is obtained by the finite-difference complex-frequency-domain (FDCFD) method. The field in the complex-frequency-domain is transformed into the time domain by fast inverse Laplace transform (FILT). The advantage of the proposed technique is that we can efficiently obtain the response at required observation time by parallel computing. As a numerical example of applications, a plasmonic waveguide array (PWA) using metallic slabs is designed for quantum walk toward developing quantum information technology. Properties of PWA will be discussed in comparison with classical random walk.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117220262","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021525
A. J. Arand, B. Abbasi Arand
In this article the dipole antenna with AMC reflector is studied. The reason for the degradation in dipole antenna located near to the High Impedance Surface structure is examined. To do this, the pattern for various frequencies is reviewed and the effect of the reflection phase of reflector and its distance to antenna on pattern is explored. The printed dipole antenna and the proposed AMC unit cell are provided. According to the investigation, the antenna backed AMC reflector with three different reflection phases and distance is designed. Also, the size of AMC dimension on radiation parameter is tested.
{"title":"Radiation Performance Improvement of Microstrip Antenna Using AMC Structure","authors":"A. J. Arand, B. Abbasi Arand","doi":"10.1109/PIERS-Fall48861.2019.9021525","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021525","url":null,"abstract":"In this article the dipole antenna with AMC reflector is studied. The reason for the degradation in dipole antenna located near to the High Impedance Surface structure is examined. To do this, the pattern for various frequencies is reviewed and the effect of the reflection phase of reflector and its distance to antenna on pattern is explored. The printed dipole antenna and the proposed AMC unit cell are provided. According to the investigation, the antenna backed AMC reflector with three different reflection phases and distance is designed. Also, the size of AMC dimension on radiation parameter is tested.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121120048","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 : 2019-12-01DOI: 10.1109/PIERS-Fall48861.2019.9021379
S. Tuan
In many engineering applications, narrow scanning beam on array antenna is required but not the corresponding gains. This type of application can be achieved by the aperiodic array on array aperture of the antenna elements. Using less antenna elements to realize the technical index of resolution, thereby further reducing the cost of antenna system. This paper is proposed using genetic algorithm technology on the optimal aperiodic distributed array antenna of millimeter wave with the expectation of lowering the peak sidelobe level on the aperiodic distributed array and increasing gains through effective array formation under the restraint limitation and conditions. Setting the establishment of the lowest PSLL (peak side-lobes level) as the optimal target, it is an optimal technology in which the array element’s position is set as the optimal variables for the aperiodic distributed line array and for aperiodic distributed rectangular boundary planar array of the millimeter wave. The final target is to establish the optimal array technology for aperiodic distributed planar array of millimeter wave under the limitation on number of array elements, aperture size, and minimum array elements interval space.
{"title":"Side Lobes Suppressing Technology for Aperiodic Millimeter Wave Array Antenna","authors":"S. Tuan","doi":"10.1109/PIERS-Fall48861.2019.9021379","DOIUrl":"https://doi.org/10.1109/PIERS-Fall48861.2019.9021379","url":null,"abstract":"In many engineering applications, narrow scanning beam on array antenna is required but not the corresponding gains. This type of application can be achieved by the aperiodic array on array aperture of the antenna elements. Using less antenna elements to realize the technical index of resolution, thereby further reducing the cost of antenna system. This paper is proposed using genetic algorithm technology on the optimal aperiodic distributed array antenna of millimeter wave with the expectation of lowering the peak sidelobe level on the aperiodic distributed array and increasing gains through effective array formation under the restraint limitation and conditions. Setting the establishment of the lowest PSLL (peak side-lobes level) as the optimal target, it is an optimal technology in which the array element’s position is set as the optimal variables for the aperiodic distributed line array and for aperiodic distributed rectangular boundary planar array of the millimeter wave. The final target is to establish the optimal array technology for aperiodic distributed planar array of millimeter wave under the limitation on number of array elements, aperture size, and minimum array elements interval space.","PeriodicalId":197451,"journal":{"name":"2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121362366","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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