Pub Date : 2015-10-29DOI: 10.1109/APSAR.2015.7306252
Yueting Zhang, Fangfang Li, Xiaolan Qiu, C. Ding
The Multi-Bounce (MB) scattering characteristics in SAR image of tanks with floating top give valuable information about the reserve of the tank. In this work, in order to analyze the characteristics of the MB scattering for objects with cavity shape, an approach to simulate by using Shooting and Bouncing Rays (SBR) technique is presented. The MB scattering mechanism is calculated by using ray perspective, and the approximate focus positions of the MB rays are approximately deduced according to imaging formation progress. By using this method, the simulated SAR image is obtained by avoiding the calculation of the 2-D scattered field. The characteristics of the simulated results show agreement with the Terra-SAR data of the tanks with floating top.
{"title":"An approach for simulating SAR images of tanks by using shooting and bouncing rays","authors":"Yueting Zhang, Fangfang Li, Xiaolan Qiu, C. Ding","doi":"10.1109/APSAR.2015.7306252","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306252","url":null,"abstract":"The Multi-Bounce (MB) scattering characteristics in SAR image of tanks with floating top give valuable information about the reserve of the tank. In this work, in order to analyze the characteristics of the MB scattering for objects with cavity shape, an approach to simulate by using Shooting and Bouncing Rays (SBR) technique is presented. The MB scattering mechanism is calculated by using ray perspective, and the approximate focus positions of the MB rays are approximately deduced according to imaging formation progress. By using this method, the simulated SAR image is obtained by avoiding the calculation of the 2-D scattered field. The characteristics of the simulated results show agreement with the Terra-SAR data of the tanks with floating top.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134252143","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306247
Di Wu, Daiyin Zhu, X. Mao, Yong Li, M. Shen
An efficient approach to achieve ground moving target indication (GMTI) for synthetic aperture radar (SAR) is to use the Monopulse-SAR system. This paper examines the statistics of complex monopulse ratio (CMR) for SAR/GMTI model when complex Gaussian clutter-plus-noise is considered. The two dimensional probability density function (pdf) of CMR is analyzed in detail. An automatic constant false-alarm rate (CFAR) detector with the probability of false alarm given in a closed-form for moving targets is provided and extended to a multi-CMRD form to further improve the final detection performance. Experimental results are presented to examine the detection performance and validate the theoretical analysis.
{"title":"CFAR detection of moving target for Monopulse-SAR based on statistical analysis of complex monopulse ratio","authors":"Di Wu, Daiyin Zhu, X. Mao, Yong Li, M. Shen","doi":"10.1109/APSAR.2015.7306247","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306247","url":null,"abstract":"An efficient approach to achieve ground moving target indication (GMTI) for synthetic aperture radar (SAR) is to use the Monopulse-SAR system. This paper examines the statistics of complex monopulse ratio (CMR) for SAR/GMTI model when complex Gaussian clutter-plus-noise is considered. The two dimensional probability density function (pdf) of CMR is analyzed in detail. An automatic constant false-alarm rate (CFAR) detector with the probability of false alarm given in a closed-form for moving targets is provided and extended to a multi-CMRD form to further improve the final detection performance. Experimental results are presented to examine the detection performance and validate the theoretical analysis.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133500629","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306309
Yaolong Qi, Yanping Wang, Xiaolin Yang, Husheng Li
Regional deformation monitoring is important for early warning of deformation disasters. This paper focuses on the applications of microwave imaging in deformation monitoring based on ground-based SAR. Specifically, the paper mainly studies the microwave image reconstruction and deformation information extraction firstly. Then, matching principle and method of auxiliary terrain data and microwave image is analyzed. Based on the key technologies above, the paper carry out point target deformation monitoring experiment in laboratory and slope deformation monitoring experiment in a mine slope, which can verify the correctness of the models and the accuracy of the methods.
{"title":"Application of microwave imaging in regional deformation monitoring using ground based SAR","authors":"Yaolong Qi, Yanping Wang, Xiaolin Yang, Husheng Li","doi":"10.1109/APSAR.2015.7306309","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306309","url":null,"abstract":"Regional deformation monitoring is important for early warning of deformation disasters. This paper focuses on the applications of microwave imaging in deformation monitoring based on ground-based SAR. Specifically, the paper mainly studies the microwave image reconstruction and deformation information extraction firstly. Then, matching principle and method of auxiliary terrain data and microwave image is analyzed. Based on the key technologies above, the paper carry out point target deformation monitoring experiment in laboratory and slope deformation monitoring experiment in a mine slope, which can verify the correctness of the models and the accuracy of the methods.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":" 896","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113947047","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306332
Huajian Xu, Zhiwei Yang, Rui Zhang, G. Liao
In the remote observation, utilizing multi-channel high-resolution SAR images to detect slow moving ground targets will be confronted with the problem of low signal to noise ratio (SNR). Fortunately, the use of the geometric relationship between the moving object and its shadow in significant size can improve the target detection performance. In this paper, based on the shadow formation model of a slow moving target, matching conditions are designed to exclude the false targets that do not satisfy them by employing the geometric relationship between the moving object and its shadow, which can reduce false alarms and improve slow ground moving target detection performance. Compared to the traditional cell average CFAR (CA-CFAR) method, simulation results show that the shadow-aided method can improve the detection performance of 2~3dB.
{"title":"Shadow-aided method for ground slow moving targets detection of airborne high-resolution SAR images","authors":"Huajian Xu, Zhiwei Yang, Rui Zhang, G. Liao","doi":"10.1109/APSAR.2015.7306332","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306332","url":null,"abstract":"In the remote observation, utilizing multi-channel high-resolution SAR images to detect slow moving ground targets will be confronted with the problem of low signal to noise ratio (SNR). Fortunately, the use of the geometric relationship between the moving object and its shadow in significant size can improve the target detection performance. In this paper, based on the shadow formation model of a slow moving target, matching conditions are designed to exclude the false targets that do not satisfy them by employing the geometric relationship between the moving object and its shadow, which can reduce false alarms and improve slow ground moving target detection performance. Compared to the traditional cell average CFAR (CA-CFAR) method, simulation results show that the shadow-aided method can improve the detection performance of 2~3dB.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"290 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115862930","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306264
T. Balz, M. Liao, B. Fu, G. Caspari, R. Rosenbauer, S. Erasmi
Remotely sensed data can support archaeological prospections in many ways and is therefore widely used. However, synthetic aperture radar (SAR) data is far less commonly used, although with the newest generation of high-resolution SAR systems and the additional very high resolution staring spotlight mode of TerraSAR-X, the spatial resolution of spaceborne SAR systems are suitable for many archaeological applications. We demonstrate the suitability of very high resolution TerraSAR-X data for the detection of archaeological structures in the Chinese Altai Mountains. SAR interferometry can further enhance the interpretability of the remotely sensed data. However, interferometrie SAR is rather sensitive for atmospheric changes and changes on the ground and can therefore not always be used successfully.
{"title":"Analyzing TerraSAR-X staring spotlight mode data for archaeological prospections in the Altai Mountains","authors":"T. Balz, M. Liao, B. Fu, G. Caspari, R. Rosenbauer, S. Erasmi","doi":"10.1109/APSAR.2015.7306264","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306264","url":null,"abstract":"Remotely sensed data can support archaeological prospections in many ways and is therefore widely used. However, synthetic aperture radar (SAR) data is far less commonly used, although with the newest generation of high-resolution SAR systems and the additional very high resolution staring spotlight mode of TerraSAR-X, the spatial resolution of spaceborne SAR systems are suitable for many archaeological applications. We demonstrate the suitability of very high resolution TerraSAR-X data for the detection of archaeological structures in the Chinese Altai Mountains. SAR interferometry can further enhance the interpretability of the remotely sensed data. However, interferometrie SAR is rather sensitive for atmospheric changes and changes on the ground and can therefore not always be used successfully.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117230471","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306201
Zhenyu Li, Yi Liang, M. Xing, Jun Wu
A new approach of highly squinted SAR sub-aperture data processing is proposed in this paper. Under the condition of the sub-aperture characteristics, this paper presents a frequency phase correction algorithm (FPCA) for focusing SAR sub-aperture data acquired at a high squint angle and wide azimuth swath width. By introducing a disturbing phase in the azimuth frequency domain, the FPCA eliminates the azimuth-dependent frequency modulation (FM) rate and improves the final image quality effectively. The whole procedure only involves fast Fourier transforms (FFTs) and complex multiplications, with interpolation free, simulated results and raw data processing validate the effectiveness of the proposed algorithm.
{"title":"A sub-aperture imaging algorithm for highly squinted SAR based on frequency phase correction","authors":"Zhenyu Li, Yi Liang, M. Xing, Jun Wu","doi":"10.1109/APSAR.2015.7306201","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306201","url":null,"abstract":"A new approach of highly squinted SAR sub-aperture data processing is proposed in this paper. Under the condition of the sub-aperture characteristics, this paper presents a frequency phase correction algorithm (FPCA) for focusing SAR sub-aperture data acquired at a high squint angle and wide azimuth swath width. By introducing a disturbing phase in the azimuth frequency domain, the FPCA eliminates the azimuth-dependent frequency modulation (FM) rate and improves the final image quality effectively. The whole procedure only involves fast Fourier transforms (FFTs) and complex multiplications, with interpolation free, simulated results and raw data processing validate the effectiveness of the proposed algorithm.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115213171","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306195
Yuto Osanai, J. Sumantyo, Zafri Baharaddin
This paper presents a development of circularly polarized microstrip antenna using Kevlar honeycomb core as the substrates for application of Circularly Polarized Synthetic Aperture Radar (CP-SAR) which signal propagation is not affected by Faraday rotation effect in the ionosphere, as compared to linearly polarized systems especially at the L-band. The reason why Kevlar honeycomb core is used is because it is suitable for space environment in terms of lightweight and resistant to heat and shock. Measurements of the fabricated antenna were performed to confirm the simulation results. The results show good characteristics of the antennas except the axial ratio. The reason of insufficient axial ratio is assumed as fabrication error of the radiator and microstrip line.
{"title":"Development of spaceborne antenna for circularly polarized SAR using Kevlar honeycomb core","authors":"Yuto Osanai, J. Sumantyo, Zafri Baharaddin","doi":"10.1109/APSAR.2015.7306195","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306195","url":null,"abstract":"This paper presents a development of circularly polarized microstrip antenna using Kevlar honeycomb core as the substrates for application of Circularly Polarized Synthetic Aperture Radar (CP-SAR) which signal propagation is not affected by Faraday rotation effect in the ionosphere, as compared to linearly polarized systems especially at the L-band. The reason why Kevlar honeycomb core is used is because it is suitable for space environment in terms of lightweight and resistant to heat and shock. Measurements of the fabricated antenna were performed to confirm the simulation results. The results show good characteristics of the antennas except the axial ratio. The reason of insufficient axial ratio is assumed as fabrication error of the radiator and microstrip line.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125311896","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306180
D. Tridon, M. Bachmann, Johannes Boer, B. Brautigam, Carolina González, T. Kraus, G. Krieger, M. Martone, Maria Donata Polimeni, D. Schulze, Christopher Wecklich, M. Zink
TanDEM-X is an innovative spaceborne X-band SAR mission designed to derive a digital elevation model (DEM) of the Earth's land surface with an unprecedented relative vertical accuracy of 2m at a 12m posting. The global DEM is derived from interferometric SAR acquisitions performed by two radar satellites flying in close orbit formation, with adjustable baselines in cross- and in along-track directions. This paper provides an overview of the present mission status in terms of acquisition strategy and a quality summary of the currently available parts of the TanDEM-X global DEM in terms of absolute and relative height accuracy.
{"title":"TanDEM-X going for the DEM: Acquisition, performance, and further activities","authors":"D. Tridon, M. Bachmann, Johannes Boer, B. Brautigam, Carolina González, T. Kraus, G. Krieger, M. Martone, Maria Donata Polimeni, D. Schulze, Christopher Wecklich, M. Zink","doi":"10.1109/APSAR.2015.7306180","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306180","url":null,"abstract":"TanDEM-X is an innovative spaceborne X-band SAR mission designed to derive a digital elevation model (DEM) of the Earth's land surface with an unprecedented relative vertical accuracy of 2m at a 12m posting. The global DEM is derived from interferometric SAR acquisitions performed by two radar satellites flying in close orbit formation, with adjustable baselines in cross- and in along-track directions. This paper provides an overview of the present mission status in terms of acquisition strategy and a quality summary of the currently available parts of the TanDEM-X global DEM in terms of absolute and relative height accuracy.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126590220","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306294
B. Adriano, E. Mas, S. Koshimura
In this study, a practical methodology is presented to classify and map damaged buildings, following the 2013 Super Typhoon Haiyan, using high resolution synthetic aperture radar (SAR) images and post-event building damage data from Tacloban city, The Philippines. Considering the relationship of the radar layover extension between damaged and non-damaged structures, the method focuses on the changes in the building radar signature between pre- and post-event SAR scenes. In addition, the method introduces a new change factor for change detection analysis. The method was developed and tested using a 1.0 m resolution COSMO-SkyMed SAR images taken over Tacloban city, the Philippines. The method proves, with 76% accuracy in this case, to be suitable for estimating destroyed buildings.
{"title":"Buildings damage due to the 2013 Haiyan Typhoon inferred from SAR intensity images","authors":"B. Adriano, E. Mas, S. Koshimura","doi":"10.1109/APSAR.2015.7306294","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306294","url":null,"abstract":"In this study, a practical methodology is presented to classify and map damaged buildings, following the 2013 Super Typhoon Haiyan, using high resolution synthetic aperture radar (SAR) images and post-event building damage data from Tacloban city, The Philippines. Considering the relationship of the radar layover extension between damaged and non-damaged structures, the method focuses on the changes in the building radar signature between pre- and post-event SAR scenes. In addition, the method introduces a new change factor for change detection analysis. The method was developed and tested using a 1.0 m resolution COSMO-SkyMed SAR images taken over Tacloban city, the Philippines. The method proves, with 76% accuracy in this case, to be suitable for estimating destroyed buildings.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125088276","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306335
Wen Liu, L. Moya, F. Yamazaki
An Mw6.2 earthquake hit northern Nagano prefecture, Japan on November 22, 2014, with 46 people injured and a lot of damage to houses. Due to the fault movement, about 1-m displacement was observed by field surveys after the earthquake. Interferomatic SAR (InSAR) analysis has been confirmed as an effective tool to detect displacements in the centimeter level. In this study, the pre- and post-event ALOS-2 PALSAR-2 data were used to grasp the displacements around the Kamishiro Fault by the differential InSAR analysis. The slant range movements were obtained according to the phase differences. Then a fault model was built by introducing the parameters published by the Global Centroid-Moment-Tensor Catalog. A three-dimensional displacement was simulated using the fault model and it was compared with the observation result by a GPS ground station and at a strong-motion station.
{"title":"Extraction of coseismic displacement in the November 22, 2014 Nagano, Japan earthquake from ALOS-2 images","authors":"Wen Liu, L. Moya, F. Yamazaki","doi":"10.1109/APSAR.2015.7306335","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306335","url":null,"abstract":"An Mw6.2 earthquake hit northern Nagano prefecture, Japan on November 22, 2014, with 46 people injured and a lot of damage to houses. Due to the fault movement, about 1-m displacement was observed by field surveys after the earthquake. Interferomatic SAR (InSAR) analysis has been confirmed as an effective tool to detect displacements in the centimeter level. In this study, the pre- and post-event ALOS-2 PALSAR-2 data were used to grasp the displacements around the Kamishiro Fault by the differential InSAR analysis. The slant range movements were obtained according to the phase differences. Then a fault model was built by introducing the parameters published by the Global Centroid-Moment-Tensor Catalog. A three-dimensional displacement was simulated using the fault model and it was compared with the observation result by a GPS ground station and at a strong-motion station.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130779605","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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