{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T20:59:26Z","timestamp":1774645166653,"version":"3.50.1"},"reference-count":23,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2022,10,18]],"date-time":"2022-10-18T00:00:00Z","timestamp":1666051200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"MSIT (Ministry of Science, ICT), Korea, under the High-Potential Individuals Global Training Program","award":["2021-0-02133"],"award-info":[{"award-number":["2021-0-02133"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper introduces an indoor-monitoring LiDAR sensor for patients with Alzheimer disease residing in long-term care facilities (LTCFs), and this sensor exploits an optoelectronic analog front-end (AFE) to detect light signals from targets by utilizing on-chip avalanche photodiodes (APDs) realized in a 180 nm CMOS process and a neural processing unit (NPU) used for motion detection and decisions, especially for incidents of falls occurring in LTCFs. The AFE consists of an on-chip CMOS P+\/N-well APD, a linear-mode transimpedance amplifier, a post-amplifier, and a time-to-digital converter, whereas the NPU exploits network sparsity and approximate processing elements for low-power operation. This work provides a potential solution of low-cost, low-power, indoor-monitoring LiDAR sensors for patients with Alzheimer disease in LTCFs.<\/jats:p>","DOI":"10.3390\/s22207934","type":"journal-article","created":{"date-parts":[[2022,10,19]],"date-time":"2022-10-19T00:58:51Z","timestamp":1666141131000},"page":"7934","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["An Indoor-Monitoring LiDAR Sensor for Patients with Alzheimer Disease Residing in Long-Term Care Facilities"],"prefix":"10.3390","volume":"22","author":[{"given":"Ji-Eun","family":"Joo","sequence":"first","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}]},{"given":"Yu","family":"Hu","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}]},{"given":"Sujin","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}]},{"given":"Hyunji","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}]},{"given":"Sunyoung","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}]},{"given":"Ji-Hoon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5287-9235","authenticated-orcid":false,"given":"Younghyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronic and Computer Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA"}]},{"given":"Sung-Min","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,18]]},"reference":[{"key":"ref_1","first-page":"5589","article-title":"Mirrored current-conveyor transimpedance amplifier for home minotoring LiDAR sensors","volume":"20","author":"Yoon","year":"2020","journal-title":"IEEE Sensors J."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Joo, J., Lee, M.-J., and Park, S.M. 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