{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T14:37:23Z","timestamp":1775054243187,"version":"3.50.1"},"reference-count":54,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2018,5,19]],"date-time":"2018-05-19T00:00:00Z","timestamp":1526688000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Combining persistent scatterers (PS) and distributed scatterers (DS) is important for effective displacement monitoring using time-series of SAR data. However, for large stacks of synthetic aperture radar (SAR) data, the DS analysis using existing algorithms becomes a time-consuming process. Moreover, the whole procedure of DS selection should be repeated as soon as a new SAR acquisition is made, which is challenging considering the short repeat-observation of missions such as Sentinel-1. SqueeSAR is an approach for extracting signals from DS, which first applies a spatiotemporal filter on images and optimizes DS, then incorporates information from both optimized DS and PS points into interferometric SAR (InSAR) time-series analysis. In this study, we followed SqueeSAR and implemented a new approach for DS analysis using two-sample t-test to efficiently identify neighboring pixels with similar behaviour. We evaluated the performance of our approach on 50 Sentinel-1 images acquired over Trondheim in Norway between January 2015 and December 2016. A cross check on the number of the identified neighboring pixels using the Kolmogorov\u2013Smirnov (KS) test, which is employed in the SqueeSAR approach, and the t-test shows that their results are strongly correlated. However, in comparison to KS-test, the t-test is less computationally intensive (98% faster). Moreover, the results obtained by applying the tests under different SAR stack sizes from 40 to 10 show that the t-test is less sensitive to the number of images.<\/jats:p>","DOI":"10.3390\/rs10050794","type":"journal-article","created":{"date-parts":[[2018,5,21]],"date-time":"2018-05-21T04:07:30Z","timestamp":1526875650000},"page":"794","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["Efficient Ground Surface Displacement Monitoring Using Sentinel-1 Data: Integrating Distributed Scatterers (DS) Identified Using Two-Sample t-Test with Persistent Scatterers (PS)"],"prefix":"10.3390","volume":"10","author":[{"given":"Roghayeh","family":"Shamshiri","sequence":"first","affiliation":[{"name":"Department of Civil and Environmental Engineering, Norwegian University of Science and Technology, 7491 Trondheim, Norway"}]},{"given":"Hossein","family":"Nahavandchi","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, Norwegian University of Science and Technology, 7491 Trondheim, Norway"}]},{"given":"Mahdi","family":"Motagh","sequence":"additional","affiliation":[{"name":"Department of Geodesy, Section of Remote Sensing, GFZ German Research Centre for Geosciences, 14473 Potsdam, Germany"},{"name":"Institute for Photogrammetry and GeoInformation, Leibniz University Hannover, 30167 Hannover, Germany"}]},{"given":"Andy","family":"Hooper","sequence":"additional","affiliation":[{"name":"Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics (COMET), School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK"}]}],"member":"1968","published-online":{"date-parts":[[2018,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1417","DOI":"10.1126\/science.1204132","article-title":"The 2010 Mw 8.8 Maule megathrust earthquake of central Chile, monitored by GPS","volume":"332","author":"Vigny","year":"2011","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s00024-005-0005-y","article-title":"Combination of precise leveling and InSAR data to constrain source parameters of the Mw = 6.5, 26 December 2003 Bam earthquake","volume":"163","author":"Motagh","year":"2006","journal-title":"Pure Appl. 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