{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T08:45:37Z","timestamp":1773996337579,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,5,31]],"date-time":"2019-05-31T00:00:00Z","timestamp":1559260800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TIN2016-78473-C3-1-R"],"award-info":[{"award-number":["TIN2016-78473-C3-1-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca","award":["2017SGR-990"],"award-info":[{"award-number":["2017SGR-990"]}]},{"name":"Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca","award":["2017-SGR-44,"],"award-info":[{"award-number":["2017-SGR-44,"]}]},{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["N\u00b0 688110 (CAPTOR project)"],"award-info":[{"award-number":["N\u00b0 688110 (CAPTOR project)"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["CGL2017-82093-ERC"],"award-info":[{"award-number":["CGL2017-82093-ERC"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>New advances in sensor technologies and communications in wireless sensor networks have favored the introduction of low-cost sensors for monitoring air quality applications. In this article, we present the results of the European project H2020 CAPTOR, where three testbeds with sensors were deployed to capture tropospheric ozone concentrations. One of the biggest challenges was the calibration of the sensors, as the manufacturer provides them without calibrating. Throughout the paper, we show how short-term calibration using multiple linear regression produces good calibrated data, but instead produces biases in the calculated long-term concentrations. To mitigate the bias, we propose a linear correction based on Kriging estimation of the mean and standard deviation of the long-term ozone concentrations, thus correcting the bias presented by the sensors.<\/jats:p>","DOI":"10.3390\/s19112503","type":"journal-article","created":{"date-parts":[[2019,5,31]],"date-time":"2019-05-31T11:59:56Z","timestamp":1559303996000},"page":"2503","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Distributed Multi-Scale Calibration of Low-Cost Ozone Sensors in Wireless Sensor Networks"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9738-2425","authenticated-orcid":false,"given":"Jose M.","family":"Barcelo-Ordinas","sequence":"first","affiliation":[{"name":"Universitat Politecnica de Catalunya (UPC), UPC Campus Nord, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2112-8516","authenticated-orcid":false,"given":"Pau","family":"Ferrer-Cid","sequence":"additional","affiliation":[{"name":"Universitat Politecnica de Catalunya (UPC), UPC Campus Nord, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5969-1182","authenticated-orcid":false,"given":"Jorge","family":"Garcia-Vidal","sequence":"additional","affiliation":[{"name":"Universitat Politecnica de Catalunya (UPC), UPC Campus Nord, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anna","family":"Ripoll","sequence":"additional","affiliation":[{"name":"Institute of Environmental Assessment and Water Research, Spanish National Research Council (IDAEA-CSIC), 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4073-3802","authenticated-orcid":false,"given":"Mar","family":"Viana","sequence":"additional","affiliation":[{"name":"Institute of Environmental Assessment and Water Research, Spanish National Research Council (IDAEA-CSIC), 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Barcelo-Ordinas, J.M., Chanet, J.P., Hou, K.M., and Garc\u00eda-Vidal, J. 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