{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T16:14:21Z","timestamp":1781108061130,"version":"3.54.1"},"reference-count":46,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,6,22]],"date-time":"2023-06-22T00:00:00Z","timestamp":1687392000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Programa Estatal de I + D + i Orientada a los Retos de la Sociedad, en el marco del Plan Estatal de Investigaci\u00f3n Cient\u00edfica y T\u00e9cnica y de Innovaci\u00f3n 2017\u20132020","award":["PID2020-114467RR-C33\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["PID2020-114467RR-C33\/AEI\/10.13039\/501100011033"]}]},{"name":"Programa Estatal de I + D + i Orientada a los Retos de la Sociedad, en el marco del Plan Estatal de Investigaci\u00f3n Cient\u00edfica y T\u00e9cnica y de Innovaci\u00f3n 2017\u20132020","award":["TED2021-131040B-C31"],"award-info":[{"award-number":["TED2021-131040B-C31"]}]},{"name":"Proyectos Estrat\u00e9gicos Orientados a la Transici\u00f3n Ecol\u00f3gica y a la Transici\u00f3n Digital","award":["PID2020-114467RR-C33\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["PID2020-114467RR-C33\/AEI\/10.13039\/501100011033"]}]},{"name":"Proyectos Estrat\u00e9gicos Orientados a la Transici\u00f3n Ecol\u00f3gica y a la Transici\u00f3n Digital","award":["TED2021-131040B-C31"],"award-info":[{"award-number":["TED2021-131040B-C31"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Essential oils are valuable in various industries, but their easy adulteration can cause adverse health effects. Electronic nasal sensors offer a solution for adulteration detection. This article proposes a new system for characterising essential oils based on low-cost sensor networks and machine learning techniques. The sensors used belong to the MQ family (MQ-2, MQ-3, MQ-4, MQ-5, MQ-6, MQ-7, and MQ-8). Six essential oils were used, including Cistus ladanifer, Pinus pinaster, and Cistus ladanifer oil adulterated with Pinus pinaster, Melaleuca alternifolia, tea tree, and red fruits. A total of up to 7100 measurements were included, with more than 118 h of measurements of 33 different parameters. These data were used to train and compare five machine learning algorithms: discriminant analysis, support vector machine, k-nearest neighbours, neural network, and naive Bayesian when the data were used individually or when hourly mean values were included. To evaluate the performance of the included machine learning algorithms, accuracy, precision, recall, and F1-score were considered. The study found that using k-nearest neighbours, accuracy, recall, F1-score, and precision values were 1, 0.99, 0.99, and 1, respectively. The accuracy reached 100% with k-nearest neighbours using only 2 parameters for averaged data or 15 parameters for individual data.<\/jats:p>","DOI":"10.3390\/s23135812","type":"journal-article","created":{"date-parts":[[2023,6,23]],"date-time":"2023-06-23T02:34:07Z","timestamp":1687487647000},"page":"5812","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Proposal of a New System for Essential Oil Classification Based on Low-Cost Gas Sensor and Machine Learning Techniques"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6621-0148","authenticated-orcid":false,"given":"Sandra","family":"Viciano-Tudela","sequence":"first","affiliation":[{"name":"Instituto de Investigaci\u00f3n para la Gesti\u00f3n Integrada de Zonas Costeras, Universitat Polit\u00e8cnica de Val\u00e8ncia, C\/Paranimf, 1, 46730 Gandia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9215-8734","authenticated-orcid":false,"given":"Lorena","family":"Parra","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n para la Gesti\u00f3n Integrada de Zonas Costeras, Universitat Polit\u00e8cnica de Val\u00e8ncia, C\/Paranimf, 1, 46730 Gandia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paula","family":"Navarro-Garcia","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n para la Gesti\u00f3n Integrada de Zonas Costeras, Universitat Polit\u00e8cnica de Val\u00e8ncia, C\/Paranimf, 1, 46730 Gandia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9556-9088","authenticated-orcid":false,"given":"Sandra","family":"Sendra","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n para la Gesti\u00f3n Integrada de Zonas Costeras, Universitat Polit\u00e8cnica de Val\u00e8ncia, C\/Paranimf, 1, 46730 Gandia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0862-0533","authenticated-orcid":false,"given":"Jaime","family":"Lloret","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n para la Gesti\u00f3n Integrada de Zonas Costeras, Universitat Polit\u00e8cnica de Val\u00e8ncia, C\/Paranimf, 1, 46730 Gandia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Sharmeen, J.B., Mahomoodally, F.M., Zengin, G., and Maggi, F. 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