{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:46:04Z","timestamp":1760150764142,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,12,28]],"date-time":"2023-12-28T00:00:00Z","timestamp":1703721600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon 2020 Research and Innovation Programme","award":["739578"],"award-info":[{"award-number":["739578"]}]},{"name":"Government of the Republic of Cyprus through the Deputy Ministry of Research, Innovation and Digital Policy","award":["739578"],"award-info":[{"award-number":["739578"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Global Earth observation is becoming increasingly important in understanding and addressing critical aspects of life on our planet, including environmental issues, natural disasters, sustainable development, and others. Finding similarities in landscapes may provide useful information regarding applying contiguous policies, by making similar decisions or learning from best practices for events and occurrences that previously occurred in similar landscapes in the past. However, current applications of similar landscape retrieval are limited by a moderate performance and the need for time-consuming and costly annotations. We propose splitting the similar landscape retrieval task into a set of smaller tasks that aim to identify individual concepts inherent to satellite images. Our approach relies on several models trained using unsupervised representation learning on Google Earth images to identify these concepts. We show the efficacy of matching individual concepts for retrieving landscape(s) similar to a user-selected satellite image of the geographical territory of the Republic of Cyprus. Our results demonstrate the benefits of breaking up the landscape similarity task into individual concepts closely related to remote sensing, instead of applying a single model targeting all underlying concepts.<\/jats:p>","DOI":"10.3390\/rs16010142","type":"journal-article","created":{"date-parts":[[2023,12,28]],"date-time":"2023-12-28T11:44:57Z","timestamp":1703763897000},"page":"142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Scalable Retrieval of Similar Landscapes in Optical Satellite Imagery Using Unsupervised Representation Learning"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4034-7709","authenticated-orcid":false,"given":"Savvas","family":"Karatsiolis","sequence":"first","affiliation":[{"name":"Cyens Centre of Excellence, Dimarchou Lellou Dimitriadi 23, Nicosia 1016, Cyprus"}]},{"given":"Chirag","family":"Padubidri","sequence":"additional","affiliation":[{"name":"Cyens Centre of Excellence, Dimarchou Lellou Dimitriadi 23, Nicosia 1016, Cyprus"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8484-4256","authenticated-orcid":false,"given":"Andreas","family":"Kamilaris","sequence":"additional","affiliation":[{"name":"Cyens Centre of Excellence, Dimarchou Lellou Dimitriadi 23, Nicosia 1016, Cyprus"},{"name":"Department of Computer Science, University of Twente, 7522 NB Enschede, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,28]]},"reference":[{"key":"ref_1","unstructured":"Herschel, M., Galhardas, H., Reinwald, B., Fundulaki, I., Binnig, C., and Kaoudi, Z. 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