{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T21:39:49Z","timestamp":1784324389722,"version":"3.55.0"},"reference-count":36,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,1,31]],"date-time":"2020-01-31T00:00:00Z","timestamp":1580428800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["SOE\/P1\/E0569"],"award-info":[{"award-number":["SOE\/P1\/E0569"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Junta de Extremadura \/ FEDER","award":["IB16048"],"award-info":[{"award-number":["IB16048"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper introduces a miniaturized personal electronic nose (39 mm \u00d7 33 mm), which is managed through an app developed on a smartphone. The electronic nose (e-nose) incorporates four new generation digital gas sensors. These MOx-type sensors incorporate a microcontroller in the same package, being also smaller than the previous generation. This makes it easier to integrate them into the electronics and improves their performance. In this research, the application of the device is focused on the detection of atmospheric pollutants in order to complement the information provided by the reference stations. To validate the system, it has been tested with different concentrations of NOx including some tests specifically developed to study the behavior of the device in different humidity conditions. Finally, a mobile application has been developed to provide classification services. In this regard, a neural network has been developed, trained, and integrated into a smartphone to process the information retrieved from e-nose devices.<\/jats:p>","DOI":"10.3390\/s20030786","type":"journal-article","created":{"date-parts":[[2020,1,31]],"date-time":"2020-01-31T11:55:56Z","timestamp":1580471756000},"page":"786","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":98,"title":["Electronic Nose with Digital Gas Sensors Connected via Bluetooth to a Smartphone for Air Quality Measurements"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5918-1788","authenticated-orcid":false,"given":"Patricia","family":"Arroyo","sequence":"first","affiliation":[{"name":"Industrial Engineering School, University of Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"F\u00e9lix","family":"Mel\u00e9ndez","sequence":"additional","affiliation":[{"name":"Industrial Engineering School, University of Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7961-0244","authenticated-orcid":false,"given":"Jos\u00e9 Ignacio","family":"Su\u00e1rez","sequence":"additional","affiliation":[{"name":"Industrial Engineering School, University of Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7420-6982","authenticated-orcid":false,"given":"Jos\u00e9 Luis","family":"Herrero","sequence":"additional","affiliation":[{"name":"Industrial Engineering School, University of Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergio","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Industrial Engineering School, University of Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0905-9546","authenticated-orcid":false,"given":"Jes\u00fas","family":"Lozano","sequence":"additional","affiliation":[{"name":"Industrial Engineering School, University of Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,31]]},"reference":[{"key":"ref_1","unstructured":"WHO (2020, January 31). 9 Out of 10 People Worldwide Breathe Polluted Air, but More Countries are Taking Action. 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