{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T04:01:12Z","timestamp":1769918472199,"version":"3.49.0"},"reference-count":31,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,5,20]],"date-time":"2024-05-20T00:00:00Z","timestamp":1716163200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The paper deals with a combined time\u2013depth conversion strategy able to improve the reconstruction of voids embedded in an opaque medium, such as cavities, caves, empty hypogeal rooms, and similar targets. The combined time\u2013depth conversion accounts for the propagation velocity of the electromagnetic waves both in free space and in the embedding medium, and it allows better imaging and interpretation of the underground scenario. To assess the strategy\u2019s effectiveness, ground penetrating radar (GPR) data referred to as an experimental test in controlled conditions are accounted for and processed by two different approaches to achieve focused images of the scenario under test. The first approach is based on a classical migration algorithm, while the second one faces the imaging as a linear inverse scattering approach. The results corroborate that the combined time\u2013depth conversion improves the imaging in both cases.<\/jats:p>","DOI":"10.3390\/s24103238","type":"journal-article","created":{"date-parts":[[2024,5,20]],"date-time":"2024-05-20T06:31:58Z","timestamp":1716186718000},"page":"3238","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["GPR Mapping of Cavities in Complex Scenarios with a Combined Time\u2013Depth Conversion"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3213-2879","authenticated-orcid":false,"given":"Raffaele","family":"Persico","sequence":"first","affiliation":[{"name":"Department of Environmental Engineering DIAM, University of Calabria, Via Pietro Bucci Cubo 44A, 87036 Rende, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9031-9992","authenticated-orcid":false,"given":"Ilaria","family":"Catapano","sequence":"additional","affiliation":[{"name":"Institute for Electromagnetic Sensing of the Environment-National Research Council of Italy (IREA-CNR), Via Diocleziano 328, 80124 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8806-2895","authenticated-orcid":false,"given":"Giuseppe","family":"Esposito","sequence":"additional","affiliation":[{"name":"Institute for Electromagnetic Sensing of the Environment-National Research Council of Italy (IREA-CNR), Via Diocleziano 328, 80124 Napoli, Italy"}]},{"given":"Gianfranco","family":"Morelli","sequence":"additional","affiliation":[{"name":"Geostudi Astier srl, Via Edda Fagni 31, 57123 Livorno, Italy"}]},{"given":"Gregory","family":"De Martino","sequence":"additional","affiliation":[{"name":"Institute of Methodologies for Environmental Analyses-National Research Council of Italy (IMAA-CNR), Contrada Loya, 85050 Tito Scalo, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8594-9455","authenticated-orcid":false,"given":"Luigi","family":"Capozzoli","sequence":"additional","affiliation":[{"name":"Institute of Methodologies for Environmental Analyses-National Research Council of Italy (IMAA-CNR), Contrada Loya, 85050 Tito Scalo, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"387","DOI":"10.3997\/1873-0604.2006012","article-title":"Electrical resistivity tomography to detect buried cavities in Rome: A case study","volume":"4","author":"Cardarelli","year":"2006","journal-title":"Near Surf. 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