{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,8]],"date-time":"2025-11-08T17:13:05Z","timestamp":1762621985016,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2018,5,12]],"date-time":"2018-05-12T00:00:00Z","timestamp":1526083200000},"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":["688363"],"award-info":[{"award-number":["688363"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJGI"],"abstract":"<jats:p>Although air pollution is one of the most significant environmental factors posing a threat to human health worldwide, air quality data are scarce or not easily accessible in most European countries. The current work aims to develop a centralized air quality data hub that enables citizens to contribute to air quality monitoring. In this work, data from official air quality monitoring stations are combined with air pollution estimates from sky-depicting photos and from low-cost sensing devices that citizens build on their own so that citizens receive improved information about the quality of the air they breathe. Additionally, a data fusion algorithm merges air quality information from various sources to provide information in areas where no air quality measurements exist.<\/jats:p>","DOI":"10.3390\/ijgi7050187","type":"journal-article","created":{"date-parts":[[2018,5,14]],"date-time":"2018-05-14T02:57:20Z","timestamp":1526266640000},"page":"187","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["hackAIR: Towards Raising Awareness about Air Quality in Europe by Developing a Collective Online Platform"],"prefix":"10.3390","volume":"7","author":[{"given":"Evangelos","family":"Kosmidis","sequence":"first","affiliation":[{"name":"DRAXIS Environmental S.A., Mitropoleos 62, 54623 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2665-8831","authenticated-orcid":false,"given":"Panagiota","family":"Syropoulou","sequence":"additional","affiliation":[{"name":"DRAXIS Environmental S.A., Mitropoleos 62, 54623 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stavros","family":"Tekes","sequence":"additional","affiliation":[{"name":"DRAXIS Environmental S.A., Mitropoleos 62, 54623 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Philipp","family":"Schneider","sequence":"additional","affiliation":[{"name":"NILU-Norwegian Institute for Air Research, Instituttveien 18, 2007 Kjeller, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9178-8603","authenticated-orcid":false,"given":"Eleftherios","family":"Spyromitros-Xioufis","sequence":"additional","affiliation":[{"name":"Information Technologies Institute\u2014Centre for Research &amp; Technology Hellas, 6th Km Charilaou-Thermi Road, 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marina","family":"Riga","sequence":"additional","affiliation":[{"name":"Information Technologies Institute\u2014Centre for Research &amp; Technology Hellas, 6th Km Charilaou-Thermi Road, 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Polychronis","family":"Charitidis","sequence":"additional","affiliation":[{"name":"Information Technologies Institute\u2014Centre for Research &amp; Technology Hellas, 6th Km Charilaou-Thermi Road, 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anastasia","family":"Moumtzidou","sequence":"additional","affiliation":[{"name":"Information Technologies Institute\u2014Centre for Research &amp; Technology Hellas, 6th Km Charilaou-Thermi Road, 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Symeon","family":"Papadopoulos","sequence":"additional","affiliation":[{"name":"Information Technologies Institute\u2014Centre for Research &amp; 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Review of Evidence on Health Aspects of Air Pollution\u2014REVIHAAP Project, World Health Organization, Regional Office for Europe. Technical Report."},{"key":"ref_2","unstructured":"EEA (2018). Air Quality in Europe\u20142017 Report, European Environment Agency. EEA Report No 13\/2017."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4707","DOI":"10.1021\/es8031488","article-title":"Size fractionate particulate matter, vehicle traffic, and case-specific daily mortality in Barcelona (Spain)","volume":"43","author":"Alastuey","year":"2009","journal-title":"Environ. Sci. Technol."},{"key":"ref_4","unstructured":"International Agency for Research on Cancer (2013). Outdoor Air Pollution a Leading Environmental Cause of Cancer Deaths, WHO. Press Release No 221."},{"key":"ref_5","unstructured":"Andrews, A. (2015). The Clean Air Handbook: A Practical Guide to EU Air Quality Law, ClientEarth. Clean Air Project (Co-Financed by LIFE+)."},{"key":"ref_6","unstructured":"Biscaye, P., Clarke, J., Fowle, M., Anderson, C.L., and Reynolds, T. (2016). Global Public Goods, University of Washington. Evans School Policy Analysis and Research, Brief #325."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1186\/1476-069X-13-107","article-title":"A conceptual approach to a citizens\u2019 observatory\u2014Supporting community-based environmental governance","volume":"13","author":"Liu","year":"2014","journal-title":"Environ. Health"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"7113","DOI":"10.1016\/j.atmosenv.2011.09.035","article-title":"Digital photographic method to quantify black carbon in ambient aerosols","volume":"45","author":"Du","year":"2011","journal-title":"Atmos. Environ."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"4481","DOI":"10.1016\/j.atmosenv.2011.05.030","article-title":"A cellphone based system for large scale monitoring of black carbon","volume":"45","author":"Ramanathan","year":"2011","journal-title":"Atmos. Environ."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.trc.2011.11.012","article-title":"Visibility monitoring using conventional roadside cameras\u2014Emerging applications","volume":"22","author":"Babari","year":"2012","journal-title":"Transp. Res. Part C Emerg. Technol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"7351","DOI":"10.1002\/2014GL061462","article-title":"Mapping atmospheric aerosols with a citizen science network of smartphone spectropolarimeters","volume":"41","author":"Snik","year":"2010","journal-title":"GRL"},{"key":"ref_12","unstructured":"(2018, May 01). AMOS. Available online: http:\/\/amos.cse.wustl.edu."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Jacobs, N., Roman, N., and Pless, R. (2007, January 17\u201322). Consistent Temporal Variations in Many Outdoor Scenes. Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition (CVPR), Minneapolis, MN, USA.","DOI":"10.1109\/CVPR.2007.383258"},{"key":"ref_14","unstructured":"(2018, May 01). webcams.travel. Available online: https:\/\/www.webcams.travel."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Szegedy, C., Vanhoucke, V., Ioffe, S., Shlens, J., and Wojna, Z. (2016, January 27\u201330). Rethinking the inception architecture for computer vision. Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, Las Vegas, NV, USA.","DOI":"10.1109\/CVPR.2016.308"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Long, J., Shelhamer, E., and Darrell, T. (2015, January 7\u201312). Fully convolutional networks for semantic segmentation. Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, Boston, MA, USA.","DOI":"10.1109\/CVPR.2015.7298965"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"978","DOI":"10.1109\/TPAMI.2010.147","article-title":"Sift flow: Dense correspondence across scenes and its applications","volume":"33","author":"Liu","year":"2011","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Spyromitros-Xioufis, E., Moumtzidou, A., Papadopoulos, S., Vrochidis, S., Kompatsiaris, Y., Georgoulias, A.K., Alexandri, G., and Kourtidis, K. (2018). Towards improved air quality monitoring using publicly available sky images. Multimedia Technol. Environ. Biodivers. Inform., accepted for publication.","DOI":"10.1007\/978-3-319-76445-0_5"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Jianxiong, X., Hays, J., Ehinger, K.A., Oliva, A., and Torralba, A. (2010, January 23\u201326). Sun database: Large-scale scene recognition from abbey to zoo. Proceedings of the 20th Conference on Computer Vision and Pattern Recognition (CVPR), Istanbul, Turkey.","DOI":"10.1109\/CVPR.2010.5539970"},{"key":"ref_20","unstructured":"Spyromitros-Xioufis, E., Papadopolos, S., Moumtzidou, A., Vrochidis, S., and Kompatsiaris, Y. (2018, May 01). hackAIR Deliverable D3: 2nd Environmental Node Discovery Indexing and Data Acquisition. Available online: https:\/\/www.researchgate.net\/publication\/324594192_hackAIR_deliverable_D32_2nd_environmental_node_discovery_indexing_and_data_acquisition."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2987","DOI":"10.5194\/acp-14-2987-2014","article-title":"Further evidence of important environmental information content in red-to-green ratios as depicted in paintings by great masters","volume":"14","author":"Zerefos","year":"2014","journal-title":"Atmos. Chem. Phys."},{"key":"ref_22","unstructured":"Riffler, M., Schneider, C., Popp, C., and Wunderle, S. (2009, January 19\u201324). Deriving atmospheric visibility from satellite retrieved aerosol optical depth. Proceedings of the EGU General Assembly 2009, Vienna, Austria. Available online: http:\/\/meetings.copernicus.org\/egu2009."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"H182","DOI":"10.1364\/AO.47.00H182","article-title":"Retrieval of the optical depth using an all-sky CCD camera","volume":"47","author":"Olmo","year":"2008","journal-title":"Appl. Opt."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1007\/s00376-009-8216-2","article-title":"Preliminary retrieval of aerosol optical depth from all-sky images","volume":"27","author":"Huo","year":"2010","journal-title":"Adv. Atmos. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2013","DOI":"10.5194\/amt-5-2013-2012","article-title":"Calibration of an all-sky camera for obtaining sky radiance at three wavelengths","volume":"5","author":"Roman","year":"2012","journal-title":"Atmos. Meas. Tech."},{"key":"ref_26","first-page":"1","article-title":"Image segmentation by using thresholding techniques for medical images","volume":"6","author":"Senthilkumaran","year":"2016","journal-title":"Comput. Sci. Eng."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1007\/BF03178082","article-title":"Contrast limited adaptive histogram equalization image processing to improve the detection of simulated speculations in dense mammograms","volume":"11","author":"Pisano","year":"1988","journal-title":"J. Digit. Imaging"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3389\/fenvs.2014.00016","article-title":"Data assimilation: Making sense of Earth Observation","volume":"2","author":"Lahoz","year":"2014","journal-title":"Front. Environ. Sci."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Castell, N., Schneider, P., Grossberndt, S., Fredriksen, M.F., Sousa-Santos, G., Vogt, M., and Bartonova, A. (2017). Localized real-time information on outdoor air quality at kindergartens in Oslo, Norway using low-cost sensor nodes. Environ. Res.","DOI":"10.1016\/j.envres.2017.10.019"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1016\/j.envint.2017.05.005","article-title":"Mapping urban air quality in near real-time using observations from low-cost sensors and model information","volume":"106","author":"Schneider","year":"2017","journal-title":"Environ. Int."},{"key":"ref_31","unstructured":"Bordogna, G., and Carrara, P. (2018). A Network of Low-Cost Air Quality Sensors and Its Use for Mapping Urban Air Quality. Mobile Information Systems Leveraging Volunteered Geographic Information for Earth Observation, Springer International Publishing."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"2777","DOI":"10.5194\/gmd-8-2777-2015","article-title":"A regional air quality forecasting system over Europe: The MACC-II daily ensemble production","volume":"8","author":"Peuch","year":"2015","journal-title":"Geosci. Model Dev."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Chil\u00e8s, J.-P., and Delfiner, P. (2012). Geostatistics: Modeling Spatial Uncertainty, John Wiley & Sons. [2nd ed.].","DOI":"10.1002\/9781118136188"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Goovaerts, P. (1997). Geostatistics for Natural Resources Evaluation, Oxford University Press. [1st ed.].","DOI":"10.1093\/oso\/9780195115383.001.0001"},{"key":"ref_35","unstructured":"Isaaks, E.H., and Srivastava, R.M. (1989). An Introduction to Applied Geostatistics, Oxford University Press. [1st ed.]."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"5032","DOI":"10.1016\/j.eswa.2015.02.048","article-title":"Ontology-centered environmental information delivery for personalised decision support","volume":"42","author":"Wanner","year":"2015","journal-title":"Experts Syst. Appl."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Moumtzidou, A., Papadopoulos, S., Vrochidis, S., Kompatsiaris, I., Kourtidis, K., Hloupis, G., Stavrakas, I., Papachristopoulou, K., and Keratidis, C. (2016, January 12). Towards Air Quality Estimation Using Collected Multimodal Environmental Data. Proceedings of the IFIN 2016 and First International Workshop on Internet and Social Media for Environmental Monitoring (ISEM 2016), Florence, Italy.","DOI":"10.1007\/978-3-319-50237-3_7"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1006\/knac.1993.1008","article-title":"A translation approach to portable ontology specifications","volume":"5","author":"Gruber","year":"1993","journal-title":"Knowl. Acquis. J."},{"key":"ref_39","first-page":"239","article-title":"An Ontological Framework for Decision Support","volume":"7774","author":"Rospocher","year":"2012","journal-title":"JIST"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"4636","DOI":"10.1016\/j.jclepro.2015.08.088","article-title":"An ontology-based decision support tool for optimising domestic solar hot water system selection","volume":"112","author":"Kontopoulos","year":"2016","journal-title":"J. Clean. Prod."},{"key":"ref_41","unstructured":"Gomez, M.J., Sonnenschein, M., Vogel, U., Winter, A., Rapp, B., and Giesen, N. (2014, January 10\u201312). Towards an Environmental Information System for Semantic Stream Data. Proceedings of the 28th EnviroInfo Conference, Oldenburg, Germany."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Riga, M., Kontopoulos, E., Karatzas, K., Vrochidis, S., and Kompatsiaris, I. (2018, January 22\u201325). An Ontology-based Decision Support Framework for Personalized Quality of Life Recommendations. Proceedings of the 4th International Conference on Decision Support System Technology, (ICDSST 2018), LNBIP 313, Heraklion, Greece. (to appear).","DOI":"10.1007\/978-3-319-90315-6_4"},{"key":"ref_43","unstructured":"Knublauch, H., Hendler, J.A., and Idehen, K. (2018, May 09). SPIN\u2014Overview and Motivation. Available online: https:\/\/www.w3.org\/Submission\/spin-overview\/."},{"key":"ref_44","unstructured":"hackAIR Consortium (2018, May 09). Deliverable 4.2: Semantic Integration and Reasoning of Environmental Data. Available online: http:\/\/www.hackair.eu\/wp-content\/uploads\/2016\/03\/d4.2-semantic_integration_and_reasoning_of_environmental_data.pdf."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Schinas, M., Papadopoulos, S., Apostolidis, L., Kompatsiaris, Y., and Mitkas, P.A. (2017, January 22\u201324). Open-Source Monitoring, Search and Analytics Over Social Media. Proceedings of the International Conference on Internet Science, Thessaloniki, Greece.","DOI":"10.1007\/978-3-319-70284-1_28"}],"container-title":["ISPRS International Journal of Geo-Information"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2220-9964\/7\/5\/187\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:03:59Z","timestamp":1760195039000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2220-9964\/7\/5\/187"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,5,12]]},"references-count":45,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2018,5]]}},"alternative-id":["ijgi7050187"],"URL":"https:\/\/doi.org\/10.3390\/ijgi7050187","relation":{},"ISSN":["2220-9964"],"issn-type":[{"type":"electronic","value":"2220-9964"}],"subject":[],"published":{"date-parts":[[2018,5,12]]}}}