{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T09:12:20Z","timestamp":1773393140634,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,7,29]],"date-time":"2017-07-29T00:00:00Z","timestamp":1501286400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61301294,61601523"],"award-info":[{"award-number":["61301294,61601523"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003453","name":"Natural Science Foundation of Guangdong","doi-asserted-by":"publisher","award":["2016A030310238"],"award-info":[{"award-number":["2016A030310238"]}],"id":[{"id":"10.13039\/501100003453","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Youth Elite Project of Guangzhou University of Chinese Medicine"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Indoor human tracking and activity recognition are fundamental yet coherent problems for ambient assistive living. In this paper, we propose a method to address these two critical issues simultaneously. We construct a wireless sensor network (WSN), and the sensor nodes within WSN consist of pyroelectric infrared (PIR) sensor arrays. To capture the tempo-spatial information of the human target, the field of view (FOV) of each PIR sensor is modulated by masks. A modified partial filter algorithm is utilized to decode the location of the human target. To exploit the synergy between the location and activity, we design a two-layer random forest (RF) classifier. The initial activity recognition result of the first layer is refined by the second layer RF by incorporating various effective features. We conducted experiments in a mock apartment. The mean localization error of our system is about 0.85 m. For five kinds of daily activities, the mean accuracy for 10-fold cross-validation is above 92%. The encouraging results indicate the effectiveness of our system.<\/jats:p>","DOI":"10.3390\/s17081738","type":"journal-article","created":{"date-parts":[[2017,8,1]],"date-time":"2017-08-01T03:30:06Z","timestamp":1501558206000},"page":"1738","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":55,"title":["Simultaneous Indoor Tracking and Activity Recognition Using Pyroelectric Infrared Sensors"],"prefix":"10.3390","volume":"17","author":[{"given":"Xiaomu","family":"Luo","sequence":"first","affiliation":[{"name":"School of Medical Information Engineering, Guangzhou University of Chinese Medicine, Guangzhou 510000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiuju","family":"Guan","sequence":"additional","affiliation":[{"name":"College of Mechanical and Electrical Engineering, Zhongkai University of Agriculture Engineering, Guangzhou 510000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huoyuan","family":"Tan","sequence":"additional","affiliation":[{"name":"School of Medical Information Engineering, Guangzhou University of Chinese Medicine, Guangzhou 510000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6491-005X","authenticated-orcid":false,"given":"Liwen","family":"Gao","sequence":"additional","affiliation":[{"name":"School of Medical Information Engineering, Guangzhou University of Chinese Medicine, Guangzhou 510000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhengfei","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Medical Information Engineering, Guangzhou University of Chinese Medicine, Guangzhou 510000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoyan","family":"Luo","sequence":"additional","affiliation":[{"name":"School of Medical Information Engineering, Guangzhou University of Chinese Medicine, Guangzhou 510000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1080\/02763893.2016.1162255","article-title":"Mental Illness in Assisted Living: Challenges for Quality of Life and Care","volume":"30","author":"Morgan","year":"2016","journal-title":"J. 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