{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T03:13:14Z","timestamp":1773976394798,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,11,3]],"date-time":"2021-11-03T00:00:00Z","timestamp":1635897600000},"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>Air pollution has become the most important issue concerning human evolution in the last century, as the levels of toxic gases and particles present in the air create health problems and affect the ecosystems of the planet. Scientists and environmental organizations have been looking for new ways to combat and control the air pollution, developing new solutions as technologies evolves. In the last decade, devices able to observe and maintain pollution levels have become more accessible and less expensive, and with the appearance of the Internet of Things (IoT), new approaches for combating pollution were born. The focus of the research presented in this paper was predicting behaviours regarding the air quality index using machine learning. Data were collected from one of the six atmospheric stations set in relevant areas of Bucharest, Romania, to validate our model. Several algorithms were proposed to study the evolution of temperature depending on the level of pollution and on several pollution factors. In the end, the results generated by the algorithms are presented considering the types of pollutants for two distinct periods. Prediction errors were highlighted by the RMSE (Root Mean Square Error) for each of the three machine learning algorithms used.<\/jats:p>","DOI":"10.3390\/s21217329","type":"journal-article","created":{"date-parts":[[2021,11,3]],"date-time":"2021-11-03T21:57:49Z","timestamp":1635976669000},"page":"7329","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Pollution and Weather Reports: Using Machine Learning for Combating Pollution in Big Cities"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4939-6750","authenticated-orcid":false,"given":"Cicerone Laurentiu","family":"Popa","sequence":"first","affiliation":[{"name":"Robots and Production System Department, University Politehnica of Bucharest, Splaiul Independen\u021bei 313, 060041 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tiberiu Gabriel","family":"Dobrescu","sequence":"additional","affiliation":[{"name":"Robots and Production System Department, University Politehnica of Bucharest, Splaiul Independen\u021bei 313, 060041 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0736-343X","authenticated-orcid":false,"given":"Catalin-Ionut","family":"Silvestru","sequence":"additional","affiliation":[{"name":"Robots and Production System Department, University Politehnica of Bucharest, Splaiul Independen\u021bei 313, 060041 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandru-Cristian","family":"Firulescu","sequence":"additional","affiliation":[{"name":"Robots and Production System Department, University Politehnica of Bucharest, Splaiul Independen\u021bei 313, 060041 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Constantin Adrian","family":"Popescu","sequence":"additional","affiliation":[{"name":"Robots and Production System Department, University Politehnica of Bucharest, Splaiul Independen\u021bei 313, 060041 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8719-2743","authenticated-orcid":false,"given":"Costel Emil","family":"Cotet","sequence":"additional","affiliation":[{"name":"Robots and Production System Department, University Politehnica of Bucharest, Splaiul Independen\u021bei 313, 060041 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Xi, X., Wei, Z., Rui, X., Wang, Y., Bai, X., Yin, W., and Jin, D. 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