{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T11:25:47Z","timestamp":1780658747427,"version":"3.54.1"},"reference-count":28,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,19]],"date-time":"2023-05-19T00:00:00Z","timestamp":1684454400000},"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>Detection and monitoring of airborne hazards using e-noses has been lifesaving and prevented accidents in real-world scenarios. E-noses generate unique signature patterns for various volatile organic compounds (VOCs) and, by leveraging artificial intelligence, detect the presence of various VOCs, gases, and smokes onsite. Widespread monitoring of airborne hazards across many remote locations is possible by creating a network of gas sensors using Internet connectivity, which consumes significant power. Long-range (LoRa)-based wireless networks do not require Internet connectivity while operating independently. Therefore, we propose a networked intelligent gas sensor system (N-IGSS) which uses a LoRa low-power wide-area networking protocol for real-time airborne pollution hazard detection and monitoring. We developed a gas sensor node by using an array of seven cross-selective tin-oxide-based metal-oxide semiconductor (MOX) gas sensor elements interfaced with a low-power microcontroller and a LoRa module. Experimentally, we exposed the sensor node to six classes i.e., five VOCs plus ambient air and as released by burning samples of tobacco, paints, carpets, alcohol, and incense sticks. Using the proposed two-stage analysis space transformation approach, the captured dataset was first preprocessed using the standardized linear discriminant analysis (SLDA) method. Four different classifiers, namely AdaBoost, XGBoost, Random Forest (RF), and Multi-Layer Perceptron (MLP), were then trained and tested in the SLDA transformation space. The proposed N-IGSS achieved \u201call correct\u201d identification of 30 unknown test samples with a low mean squared error (MSE) of 1.42 \u00d7 10\u22124 over a distance of 590 m.<\/jats:p>","DOI":"10.3390\/s23104885","type":"journal-article","created":{"date-parts":[[2023,5,19]],"date-time":"2023-05-19T00:55:29Z","timestamp":1684457729000},"page":"4885","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":59,"title":["An IoT-Enabled E-Nose for Remote Detection and Monitoring of Airborne Pollution Hazards Using LoRa Network Protocol"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1152-0680","authenticated-orcid":false,"given":"Kanak","family":"Kumar","sequence":"first","affiliation":[{"name":"Department of Electronics Engineering, Indian Institute of Technology (BHU), Varanasi 221005, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5436-2977","authenticated-orcid":false,"given":"Shiv Nath","family":"Chaudhri","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Indian Institute of Technology (BHU), Varanasi 221005, India"},{"name":"Department of Electronics and Communication Engineering, Santhiram Engineering College, Nandyal 518501, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1650-011X","authenticated-orcid":false,"given":"Navin Singh","family":"Rajput","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Indian Institute of Technology (BHU), Varanasi 221005, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexey V.","family":"Shvetsov","sequence":"additional","affiliation":[{"name":"Department of Smart Technologies, Moscow Polytechnic University, 107023 Moscow, Russia"},{"name":"Department of Transport, North-Eastern Federal University, 677000 Yakutsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8019-9069","authenticated-orcid":false,"given":"Radhya","family":"Sahal","sequence":"additional","affiliation":[{"name":"School of Computer Science and IT, University College Cork, T12 K8AF Cork, Ireland"},{"name":"Faculty of Computer Science and Engineering, Hodeidah University, Al Hodeidah P.O. Box 3114, Yemen"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2857-6979","authenticated-orcid":false,"given":"Saeed Hamood","family":"Alsamhi","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Ibb University, Ibb P.O. Box 70270, Yemen"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,19]]},"reference":[{"key":"ref_1","unstructured":"WHO (2020, January 28). Household Air Pollution and Health. Available online: https:\/\/www.who.int\/en\/news-room\/factsheets\/detail\/household-air-pollution-and-health."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1016\/j.scitotenv.2012.11.056","article-title":"Footprints of air pollution and changing environment on the sustainability of built infrastructure","volume":"444","author":"Kumar","year":"2013","journal-title":"Sci. Total. 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