Geoinformatics Unit

Sadra KARIMZADEH

        

Current Position

Sadra Karimzadeh is currently a postdoctoral researcher at the Geoinformatics Unit, the RIKEN Center for Advanced Intelligence Project (AIP), Japan. His research areas are mainly seismic damage estimation using SAR remote sensing, GIS-based disaster/damage models, and site characterization.

Biography

2019 Jan - Present    Postdoctoral Researcher, RIKEN, Japan
2016 Nov - 2018 Nov    JSPS Research Fellow, Tokyo Institute of Technology, Japan
2016 Apr - 2016 Oct    Postdoctoral Research Fellow (founded by Iran's National Elites Foundation), University of Tabriz, Iran
2012 Oct - 2015 Sep    Ph.D. in Engineering, Kanazawa University, Japan

Journal Papers

  1. S. Karimzadeh and M. Matsuoka, " A Weighted Overlay Method for Liquefaction-Related Urban Damage Detection: A Case Study of the 6 September 2018 Hokkaido Eastern Iburi Earthquake, Japan ," Geosciences, vol. 8, no. 12, pp. 487, 2018.
    PDF    Quick Abstract

    Abstract: We performed interferometric synthetic aperture radar (InSAR) analyses to observe ground displacements and assess damage after the M 6.6 Hokkaido Eastern Iburi earthquake in northern Japan on 6 September 2018. A multitemporal SAR coherence map is extracted from 3-m resolution ascending (track 116) and descending (track 18) ALOS-2 Stripmap datasets to cover the entire affected area. To distinguish damaged buildings associated with liquefaction, three influential parameters from the space-based InSAR results, ground-based LiquickMap (from seismic intensities in Japanese networks) and topographic slope of the study area are considered together in a weighted overlay (WO) analysis, according to prior knowledge of the study area. The WO analysis results in liquefaction potential values that agree with our field survey results. To investigate further, we conducted microtremor measurements at 14 points in Hobetsu, in which the predominant frequency showed a negative correlation with the WO values, especially when drastic coherence decay occurred.

  2. S. Karimzadeh, M. Matsuoka, M. Miyajima, B. Adriano, A. Fallahi, and J. Karashi, " Sequential SAR Coherence Method for the Monitoring of Buildings in Sarpole-Zahab, Iran ," Remote Sensing, vol. 10, no. 8, pp. 1255, 2018.
    PDF    Quick Abstract

    Abstract: In this study, we used fifty-six synthetic aperture radar (SAR) images acquired from the Sentinel-1 C-band satellite with a regular period of 12 days (except for one image) to produce sequential phase correlation (sequential coherence) maps for the town of Sarpole-Zahab in western Iran, which experienced a magnitude 7.3 earthquake on 12 November 2017. The preseismic condition of the buildings in the town was assessed based on a long sequential SAR coherence (LSSC) method, in which we considered 55 of the 56 images to produce a coherence decay model with climatic and temporal parameters. The coseismic condition of the buildings was assessed with 3 later images and normalized RGB visualization using the short sequential SAR coherence (SSSC) method. Discriminant analysis between the completely collapsed and uncollapsed buildings was also performed for approximately 700 randomly selected buildings (for each category) by considering the heights of the buildings and the SSSC results. Finally, the area and volume of debris were calculated based on a fusion of a discriminant map and a 3D vector map of the town.