{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T11:24:32Z","timestamp":1769858672606,"version":"3.49.0"},"reference-count":55,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,30]],"date-time":"2020-12-30T00:00:00Z","timestamp":1609286400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union's Horizon 2020 research and innovation program","award":["732679"],"award-info":[{"award-number":["732679"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>Artificial Intelligence in combination with the Internet of Medical Things enables remote healthcare services through networks of environmental and\/or personal sensors. We present a remote healthcare service system which collects real-life data through an environmental sensor package, including binary motion, contact, pressure, and proximity sensors, installed at households of elderly people. Its aim is to keep the caregivers informed of subjects\u2019 health-status progressive trajectory, and alert them of health-related anomalies to enable objective on-demand healthcare service delivery at scale. The system was deployed in 19 households inhabited by an elderly person with post-stroke condition in the Emilia\u2013Romagna region in Italy, with maximal and median observation durations of 98 and 55 weeks. Among these households, 17 were multi-occupancy residences, while the other 2 housed elderly patients living alone. Subjects\u2019 daily behavioral diaries were extracted and registered from raw sensor signals, using rule-based data pre-processing and unsupervised algorithms. Personal behavioral habits were identified and compared to typical patterns reported in behavioral science, as a quality-of-life indicator. We consider the activity patterns extracted across all users as a dictionary, and represent each patient\u2019s behavior as a \u2018Bag of Words\u2019, based on which patients can be categorized into sub-groups for precision cohort treatment. Longitudinal trends of the behavioral progressive trajectory and sudden abnormalities of a patient were detected and reported to care providers. Due to the sparse sensor setting and the multi-occupancy living condition, the sleep profile was used as the main indicator in our system. Experimental results demonstrate the ability to report on subjects\u2019 daily activity pattern in terms of sleep, outing, visiting, and health-status trajectories, as well as predicting\/detecting 75% hospitalization sessions up to 11 days in advance. 65% of the alerts were confirmed to be semantically meaningful by the users. Furthermore, reduced social interaction (outing and visiting), and lower sleep quality could be observed during the COVID-19 lockdown period across the cohort.<\/jats:p>","DOI":"10.3390\/fi13010006","type":"journal-article","created":{"date-parts":[[2020,12,30]],"date-time":"2020-12-30T09:35:23Z","timestamp":1609320923000},"page":"6","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["An Unsupervised Behavioral Modeling and Alerting System Based on Passive Sensing for Elderly Care"],"prefix":"10.3390","volume":"13","author":[{"given":"Rui","family":"Hu","sequence":"first","affiliation":[{"name":"IBM Zurich Research Lab., 8803 R\u00fcschlikon, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1104-846X","authenticated-orcid":false,"given":"Bruno","family":"Michel","sequence":"additional","affiliation":[{"name":"IBM Zurich Research Lab., 8803 R\u00fcschlikon, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3409-6189","authenticated-orcid":false,"given":"Dario","family":"Russo","sequence":"additional","affiliation":[{"name":"National Research Council of Italy, 56124 Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0093-0024","authenticated-orcid":false,"given":"Niccol\u00f2","family":"Mora","sequence":"additional","affiliation":[{"name":"Department of Engineering and Architecture, University degli Studi di Parma, 43121 Parma, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0705-527X","authenticated-orcid":false,"given":"Guido","family":"Matrella","sequence":"additional","affiliation":[{"name":"Department of Engineering and Architecture, University degli Studi di Parma, 43121 Parma, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8944-2152","authenticated-orcid":false,"given":"Paolo","family":"Ciampolini","sequence":"additional","affiliation":[{"name":"Department of Engineering and Architecture, University degli Studi di Parma, 43121 Parma, Italy"}]},{"given":"Francesca","family":"Cocchi","sequence":"additional","affiliation":[{"name":"Azienda Unita\u2019 Sanitaria Locale di Parma, 43121 Parma, Italy"}]},{"given":"Enrico","family":"Montanari","sequence":"additional","affiliation":[{"name":"Azienda Unita\u2019 Sanitaria Locale di Parma, 43121 Parma, Italy"}]},{"given":"Stefano","family":"Nunziata","sequence":"additional","affiliation":[{"name":"Lepida, 40128 Bologna, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7254-3405","authenticated-orcid":false,"given":"Thomas","family":"Brunschwiler","sequence":"additional","affiliation":[{"name":"IBM Zurich Research Lab., 8803 R\u00fcschlikon, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,30]]},"reference":[{"key":"ref_1","unstructured":"United Nations (2020, December 30). 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