We analyzed the effect of loss and coupling to EIT metamaterials using circuit approach, giving the effect of two parameters: coupling and loss on the resonant property of the EIT metamaterials. To verify the results of the circuit analysis, simulations and experiments were performed. The structures were fabricated with superconducting NbN and varied temperature to verify the effect of loss. The distances were adjusted to observe the effect of the coupling strength. The results of simulations and experiments were consistent with the circuit analysis.
{"title":"TUNING ELECTROMAGNETICALLY INDUCED TRANSPARENCY OF SUPERCONDUCTING METAMATERIAL ANALYZED WITH EQUIVALENT CIRCUIT APPROACH","authors":"Yonggang Zhang, Chun-Mao Li, X. Tu","doi":"10.2528/pierm19122101","DOIUrl":"https://doi.org/10.2528/pierm19122101","url":null,"abstract":"We analyzed the effect of loss and coupling to EIT metamaterials using circuit approach, giving the effect of two parameters: coupling and loss on the resonant property of the EIT metamaterials. To verify the results of the circuit analysis, simulations and experiments were performed. The structures were fabricated with superconducting NbN and varied temperature to verify the effect of loss. The distances were adjusted to observe the effect of the coupling strength. The results of simulations and experiments were consistent with the circuit analysis.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"15 1","pages":"29-37"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81245816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhiyang Xue, Yu Mao Wu, W. Chew, Yaqiu Jin, A. Boag
The multilevel fast physical optics (MLFPO) is proposed to accelerate the computation of the fields scattered from electrically large coated scatterers. This method is based on the quadratic patch subdivision and the multilevel technology. First, the quadratic patches are employed rather than the planar patches to discretize the considered scatterer. Hence, the number of the contributing patches is cut dramatically, thus making the workload of the MLFPO method much lower than that of the traditional Gordon’s method. Next, the multilevel technology is introduced in this work to avoid calculating the physical optics scattered fields from the considered scatterer directly, so that the proposed algorithm can significantly reduce the computational complexity. Finally, numerical results have demonstrated the accuracy and efficiency of the MLFPO method based on the quadratic patches.
{"title":"THE MULTILEVEL FAST PHYSICAL OPTICS METHOD FOR CALCULATING HIGH FREQUENCY SCATTERED FIELDS","authors":"Zhiyang Xue, Yu Mao Wu, W. Chew, Yaqiu Jin, A. Boag","doi":"10.2528/pier20071203","DOIUrl":"https://doi.org/10.2528/pier20071203","url":null,"abstract":"The multilevel fast physical optics (MLFPO) is proposed to accelerate the computation of the fields scattered from electrically large coated scatterers. This method is based on the quadratic patch subdivision and the multilevel technology. First, the quadratic patches are employed rather than the planar patches to discretize the considered scatterer. Hence, the number of the contributing patches is cut dramatically, thus making the workload of the MLFPO method much lower than that of the traditional Gordon’s method. Next, the multilevel technology is introduced in this work to avoid calculating the physical optics scattered fields from the considered scatterer directly, so that the proposed algorithm can significantly reduce the computational complexity. Finally, numerical results have demonstrated the accuracy and efficiency of the MLFPO method based on the quadratic patches.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"2 1","pages":"1-15"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84567750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It becomes more and more challenging to satisfy the long-term demand of transmission capacity in wireless networks if we limit our research within the frame of traditional electromagnetic wave characteristics (e.g., frequency, amplitude, phase and polarization). The potential of orbital angular momentum (OAM) for unleashing new capacity in the severely congested spectrum of commercial communication systems is generating great interest in wireless communication field. The OAM vortex wave/beam has different topological charges, which are orthogonal to each other. It provides a new way for multiplexing in wireless communications. Electromagnetic wave or synthetic beam carrying OAM has a spiral wavefront phase structure, which may provide a new degree of freedom or better orthogonality in spatial domain. In this paper, we introduce the fundamental theory of OAM. Then, OAM generation and reception methods are equally demonstrated. Furthermore, we present the latest development of OAM in wireless communication. We further discuss the controversial topic “whether OAM provides a new degree of freedom” and illustrate our views on the relationship between OAM and MIMO. Finally, we suggest some open research directions of OAM.
{"title":"RESEARCH STATUS AND PROSPECTS OF ORBITAL ANGULAR MOMENTUM TECHNOLOGY IN WIRELESS COMMUNICATION","authors":"Feng Zheng, Yijian Chen, Siwei Ji, Gaoming Duan","doi":"10.2528/pier20091104","DOIUrl":"https://doi.org/10.2528/pier20091104","url":null,"abstract":"It becomes more and more challenging to satisfy the long-term demand of transmission capacity in wireless networks if we limit our research within the frame of traditional electromagnetic wave characteristics (e.g., frequency, amplitude, phase and polarization). The potential of orbital angular momentum (OAM) for unleashing new capacity in the severely congested spectrum of commercial communication systems is generating great interest in wireless communication field. The OAM vortex wave/beam has different topological charges, which are orthogonal to each other. It provides a new way for multiplexing in wireless communications. Electromagnetic wave or synthetic beam carrying OAM has a spiral wavefront phase structure, which may provide a new degree of freedom or better orthogonality in spatial domain. In this paper, we introduce the fundamental theory of OAM. Then, OAM generation and reception methods are equally demonstrated. Furthermore, we present the latest development of OAM in wireless communication. We further discuss the controversial topic “whether OAM provides a new degree of freedom” and illustrate our views on the relationship between OAM and MIMO. Finally, we suggest some open research directions of OAM.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"30 1","pages":"113-132"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75077125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haokui Xu, L. Tsang, J. Johnson, K. Jezek, Jie-Bang Yan, P. Gogineni
The Ultra-Wideband Software defined microwave radiometer (UWBRAD) was developed to probe internal ice sheet temperatures using 0.5–2 GHz microwave radiometry. The airborne brightness temperature data of UWBRAD show a significant reduction due to reflections of surface layering of density fluctuations making difficult the retrieval of subsurface temperature in the kilometer range of depth. Such reflections can be measured by the ultra-wideband radar in the same frequency range suggesting a combined active and passive remote sensing of polar ice sheets. In this paper, we develop a coherent reflectivity model for both ice sheet thermal emission and backscattering. Maxwell equations are used to calculate the coherent reflections from the cap layers, and the WKB approximation is used to calculate the transmission for the slowly varying profile below the cap layers. Results are then shown to demonstrate the use of radar measurements to compensate reflection effects on brightness temperatures. It is shown that the reflections corrected brightness temperature is directly related to the physical temperature and absorption profile making possible the retrieval of subsurface temperature profile with multi-frequency measurements.
{"title":"A COMBINED ACTIVE AND PASSIVE METHOD FOR THE REMOTE SENSING OF ICE SHEET TEMPERATURE PROFILES","authors":"Haokui Xu, L. Tsang, J. Johnson, K. Jezek, Jie-Bang Yan, P. Gogineni","doi":"10.2528/pier20030601","DOIUrl":"https://doi.org/10.2528/pier20030601","url":null,"abstract":"The Ultra-Wideband Software defined microwave radiometer (UWBRAD) was developed to probe internal ice sheet temperatures using 0.5–2 GHz microwave radiometry. The airborne brightness temperature data of UWBRAD show a significant reduction due to reflections of surface layering of density fluctuations making difficult the retrieval of subsurface temperature in the kilometer range of depth. Such reflections can be measured by the ultra-wideband radar in the same frequency range suggesting a combined active and passive remote sensing of polar ice sheets. In this paper, we develop a coherent reflectivity model for both ice sheet thermal emission and backscattering. Maxwell equations are used to calculate the coherent reflections from the cap layers, and the WKB approximation is used to calculate the transmission for the slowly varying profile below the cap layers. Results are then shown to demonstrate the use of radar measurements to compensate reflection effects on brightness temperatures. It is shown that the reflections corrected brightness temperature is directly related to the physical temperature and absorption profile making possible the retrieval of subsurface temperature profile with multi-frequency measurements.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"1 1","pages":"111-126"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76111055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaogang Jiang, Feihong Chen, Y. Lu, Taoce Yin, Sailing He
An all-fiber parametric oscillator which is pumped by a mode-locked Er-doped picosecond fiber laser is proposed for the generation of multi-wavelength picosecond lasing pulses. The length of a fiber-coupled optical delay line is adjusted so that the first signal wavelength is tuned closer to the pump wavelength to facilitate the generation of more lasing wavelengths. 10 orders of cascaded four-wave-mixing processes are achieved and picosecond pulses at 17 lasing wavelengths from 1264.7 nm to 1842.4 nm are demonstrated. To the best of our knowledge, this is the largest number of lasing wavelengths reported so far from a fiber optical parametric oscillator pumped with an ultrashort-pulse laser.
{"title":"GENERATING PICOSECOND PULSES WITH THE LARGEST NUMBER OF LASING WAVELENGTHS BY AN ALL-FIBER OPTICAL PARAMETRIC OSCILLATOR","authors":"Xiaogang Jiang, Feihong Chen, Y. Lu, Taoce Yin, Sailing He","doi":"10.2528/PIER20011301","DOIUrl":"https://doi.org/10.2528/PIER20011301","url":null,"abstract":"An all-fiber parametric oscillator which is pumped by a mode-locked Er-doped picosecond fiber laser is proposed for the generation of multi-wavelength picosecond lasing pulses. The length of a fiber-coupled optical delay line is adjusted so that the first signal wavelength is tuned closer to the pump wavelength to facilitate the generation of more lasing wavelengths. 10 orders of cascaded four-wave-mixing processes are achieved and picosecond pulses at 17 lasing wavelengths from 1264.7 nm to 1842.4 nm are demonstrated. To the best of our knowledge, this is the largest number of lasing wavelengths reported so far from a fiber optical parametric oscillator pumped with an ultrashort-pulse laser.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"7 1","pages":"11-17"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83179785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Moll, J. Simon, Moritz Malzer, V. Krozer, D. Pozdniakov, R. Salman, Manfred Durr, Michael Feulner, A. Nuber, H. Friedmann
This paper presents an imaging radar system for structural health monitoring (SHM) of wind turbine blades. The imaging radar system developed here is based on two frequency modulated continuous wave (FMCW) radar sensors with a high output power of 30 dBm. They have been developed for the frequency bands of 24,05 GHz-24,25 GHz and 33.4 GHz-36.0 GHz, respectively. Following the successful proof of damage detection and localization in laboratory conditions, we present here the installation of the sensor system at the tower of a 2 MW wind energy plant at 95 m above ground. The realization of the SHM-system will be introduced including the sensor system, the data acquisition framework and the signal processing procedures. We have achieved an imaging of the rotor blades using inverse synthetic aperture radar techniques under changing environmental and operational condition. On top of that, it was demonstrated that the front wall and back wall radar echo can be extracted from the measured signals demonstrating the full penetration of wind turbine blades during operation.
{"title":"Radar Imaging System for in-Service Wind Turbine Blades Inspections: Initial Results from a Field Installation at a 2 MW Wind Turbine","authors":"J. Moll, J. Simon, Moritz Malzer, V. Krozer, D. Pozdniakov, R. Salman, Manfred Durr, Michael Feulner, A. Nuber, H. Friedmann","doi":"10.2528/PIER18021905","DOIUrl":"https://doi.org/10.2528/PIER18021905","url":null,"abstract":"This paper presents an imaging radar system for structural health monitoring (SHM) of wind turbine blades. The imaging radar system developed here is based on two frequency modulated continuous wave (FMCW) radar sensors with a high output power of 30 dBm. They have been developed for the frequency bands of 24,05 GHz-24,25 GHz and 33.4 GHz-36.0 GHz, respectively. Following the successful proof of damage detection and localization in laboratory conditions, we present here the installation of the sensor system at the tower of a 2 MW wind energy plant at 95 m above ground. The realization of the SHM-system will be introduced including the sensor system, the data acquisition framework and the signal processing procedures. We have achieved an imaging of the rotor blades using inverse synthetic aperture radar techniques under changing environmental and operational condition. On top of that, it was demonstrated that the front wall and back wall radar echo can be extracted from the measured signals demonstrating the full penetration of wind turbine blades during operation.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"90 1","pages":"51-60"},"PeriodicalIF":6.7,"publicationDate":"2018-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79750324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper reviews recent advances in the design of low noise amplifier (LNA) in complementary metal oxide semiconductor (CMOS) technology for radio transceivers at microwave and millimeter wave (mmWave) frequencies. First, the evolution of wireless communication systems and CMOS technology are briefly revisited to highlight the requirements of an LNA design. Then, key performance parameters and device circuit models are described. Next, we discuss typical LNA topologies, followed by those important design techniques, algorithms and concepts developed specifically for CMOS LNAs. Moreover, reported CMOS LNA designs are summarized, and future design issues are identified. Finally, we conclude the paper and briefly outline our future work on CMOS LNA designs.
{"title":"CMOS LOW NOISE AMPLIFIER DESIGN FOR MICROWAVE AND MMWAVE APPLICATIONS (INVITED REVIEW)","authors":"Xue Jun Li, Yue Ping Zhang","doi":"10.2528/pier18012410","DOIUrl":"https://doi.org/10.2528/pier18012410","url":null,"abstract":"This paper reviews recent advances in the design of low noise amplifier (LNA) in complementary metal oxide semiconductor (CMOS) technology for radio transceivers at microwave and millimeter wave (mmWave) frequencies. First, the evolution of wireless communication systems and CMOS technology are briefly revisited to highlight the requirements of an LNA design. Then, key performance parameters and device circuit models are described. Next, we discuss typical LNA topologies, followed by those important design techniques, algorithms and concepts developed specifically for CMOS LNAs. Moreover, reported CMOS LNA designs are summarized, and future design issues are identified. Finally, we conclude the paper and briefly outline our future work on CMOS LNA designs.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"22 1","pages":"57-85"},"PeriodicalIF":6.7,"publicationDate":"2018-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87388376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Synthetic Aperture Radar (SAR) image registration is to establish reliable correspondences among the images of the same scene. It is a challenging problem to register the airborne SAR images for the instability of airborne SAR systems and the lack of appropriate geo-reference data. Besides, techniques for registering satellite-based SAR images relying on rigorous SAR geocoding cannot be directly applied to airborne SAR images. To address this problem, we present a coarse-to-fine registration method for airborne SAR images by combining SAR-FAST (Features from Accelerated Segment Test) feature detector and DSP-LATCH (Domain-Size Pooling of Learned Arrangements of Three patCH) feature descriptor, which only relies on the gray level intensity of SAR data. More precisely, we first apply SAR-FAST, which is an adapted version of FAST for analyzing SAR images, to detect corners with high accuracy and low computational complexity. To reduce the disturbance of speckle noise as well as to achieve efficient and discriminative feature description, we further propose an improved descriptor named DSP-LATCH to describe the features, which combines the Domain-size Pooling scheme of DSP-SIFT (Scale-Invariant Feature Transform) and the idea of comparing triplets of patches rather than individual pixel values of LATCH. Finally, we conduct a coarse-to-fine strategy for SAR image registration by employing binary feature matching and the Powell algorithm. Compared with the existing feature based SAR image registration methods, e.g., SIFT and its variants, our method yields more reliable matched feature points and achieves higher registration accuracy. The experimental results on different scenes of airborne SAR images demonstrate the superiority of the proposed method in terms of robustness and accuracy.
{"title":"Coarse-to-Fine Accurate Registration for Airborne SAR Images Using SAR-Fast and DSP-LATCH","authors":"Huai Yu, Wen Yang, Yan Liu","doi":"10.2528/PIER18070801","DOIUrl":"https://doi.org/10.2528/PIER18070801","url":null,"abstract":"Synthetic Aperture Radar (SAR) image registration is to establish reliable correspondences among the images of the same scene. It is a challenging problem to register the airborne SAR images for the instability of airborne SAR systems and the lack of appropriate geo-reference data. Besides, techniques for registering satellite-based SAR images relying on rigorous SAR geocoding cannot be directly applied to airborne SAR images. To address this problem, we present a coarse-to-fine registration method for airborne SAR images by combining SAR-FAST (Features from Accelerated Segment Test) feature detector and DSP-LATCH (Domain-Size Pooling of Learned Arrangements of Three patCH) feature descriptor, which only relies on the gray level intensity of SAR data. More precisely, we first apply SAR-FAST, which is an adapted version of FAST for analyzing SAR images, to detect corners with high accuracy and low computational complexity. To reduce the disturbance of speckle noise as well as to achieve efficient and discriminative feature description, we further propose an improved descriptor named DSP-LATCH to describe the features, which combines the Domain-size Pooling scheme of DSP-SIFT (Scale-Invariant Feature Transform) and the idea of comparing triplets of patches rather than individual pixel values of LATCH. Finally, we conduct a coarse-to-fine strategy for SAR image registration by employing binary feature matching and the Powell algorithm. Compared with the existing feature based SAR image registration methods, e.g., SIFT and its variants, our method yields more reliable matched feature points and achieves higher registration accuracy. The experimental results on different scenes of airborne SAR images demonstrate the superiority of the proposed method in terms of robustness and accuracy.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"198 1","pages":"89-106"},"PeriodicalIF":6.7,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80013382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Because of the maneuvering of hypersonic target, the tracking of near space hypersonic targets is difficult. In this paper, a new adaptive tracking algorithm based on an aerodynamic model and improved square root cubature Kalman filter is proposed. The adaptive piecewise constant jerk model gives the acceleration recursive process based on the dynamic model. Considering the nonlinear characteristic of both the target state model and the observation model, the improved square-root cubature Kalman filter is applied to estimate the target state. The simulation results under different maneuvers conditions indicate that the proposed method has a higher degree of accuracy than the original aerodynamic model. The research provides a feasible solution to the further improvement of the real time tracking accuracy of near space hypersonic targets.
{"title":"A New Adaptive Tracking Algorithm for Near-Space Hypersonic Target","authors":"Xiangke Guo, Changyun Liu, Fu Qiang, Wang Gang","doi":"10.2528/PIERM18070102","DOIUrl":"https://doi.org/10.2528/PIERM18070102","url":null,"abstract":"Because of the maneuvering of hypersonic target, the tracking of near space hypersonic targets is difficult. In this paper, a new adaptive tracking algorithm based on an aerodynamic model and improved square root cubature Kalman filter is proposed. The adaptive piecewise constant jerk model gives the acceleration recursive process based on the dynamic model. Considering the nonlinear characteristic of both the target state model and the observation model, the improved square-root cubature Kalman filter is applied to estimate the target state. The simulation results under different maneuvers conditions indicate that the proposed method has a higher degree of accuracy than the original aerodynamic model. The research provides a feasible solution to the further improvement of the real time tracking accuracy of near space hypersonic targets.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"33 1","pages":"119-129"},"PeriodicalIF":6.7,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76195479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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