{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T17:51:41Z","timestamp":1778003501615,"version":"3.51.4"},"reference-count":53,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,10,25]],"date-time":"2021-10-25T00:00:00Z","timestamp":1635120000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2017R1A5A1015596"],"award-info":[{"award-number":["NRF-2017R1A5A1015596"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Research Grant of Kwangwoon University in 2021"},{"DOI":"10.13039\/501100003052","name":"Ministry of Trade, Industry and Energy","doi-asserted-by":"publisher","award":["20002862"],"award-info":[{"award-number":["20002862"]}],"id":[{"id":"10.13039\/501100003052","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Wearable technologies are known to improve our quality of life. Among the various wearable devices, shoes are non-intrusive, lightweight, and can be used for outdoor activities. In this study, we estimated the energy consumption and heart rate in an environment (i.e., running on a treadmill) using smart shoes equipped with triaxial acceleration, triaxial gyroscope, and four-point pressure sensors. The proposed model uses the latest deep learning architecture which does not require any separate preprocessing. Moreover, it is possible to select the optimal sensor using a channel-wise attention mechanism to weigh the sensors depending on their contributions to the estimation of energy expenditure (EE) and heart rate (HR). The performance of the proposed model was evaluated using the root mean squared error (RMSE), mean absolute error (MAE), and coefficient of determination (R2). Moreover, the RMSE was 1.05 \u00b1 0.15, MAE 0.83 \u00b1 0.12 and R2 0.922 \u00b1 0.005 in EE estimation. On the other hand, and RMSE was 7.87 \u00b1 1.12, MAE 6.21 \u00b1 0.86, and R2 0.897 \u00b1 0.017 in HR estimation. In both estimations, the most effective sensor was the z axis of the accelerometer and gyroscope sensors. Through these results, it is demonstrated that the proposed model could contribute to the improvement of the performance of both EE and HR estimations by effectively selecting the optimal sensors during the active movements of participants.<\/jats:p>","DOI":"10.3390\/s21217058","type":"journal-article","created":{"date-parts":[[2021,10,25]],"date-time":"2021-10-25T21:42:05Z","timestamp":1635198125000},"page":"7058","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Deep Learning-Based Optimal Smart Shoes Sensor Selection for Energy Expenditure and Heart Rate Estimation"],"prefix":"10.3390","volume":"21","author":[{"given":"Heesang","family":"Eom","sequence":"first","affiliation":[{"name":"Department of Computer Engineering, Kwangwoon University, Seoul 01897, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jongryun","family":"Roh","sequence":"additional","affiliation":[{"name":"Digital Transformation R&D Department, Korea Institute of Industrial Technology (KITECH), 143 Hanggaulro, Ansan 15588, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0618-3082","authenticated-orcid":false,"given":"Yuli Sun","family":"Hariyani","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Kwangwoon University, Seoul 01897, Korea"},{"name":"School of Applied Science, Telkom University, Bandung 40257, Indonesia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5913-4471","authenticated-orcid":false,"given":"Suwhan","family":"Baek","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Kwangwoon University, Seoul 01897, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sukho","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Leisure Sports, College of Ecological Environment, Kyungpook National University, Sangju-si 37224, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sayup","family":"Kim","sequence":"additional","affiliation":[{"name":"Digital Transformation R&D Department, Korea Institute of Industrial Technology (KITECH), 143 Hanggaulro, Ansan 15588, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8042-007X","authenticated-orcid":false,"given":"Cheolsoo","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Kwangwoon University, Seoul 01897, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1109\/MEMB.2003.1213625","article-title":"Enhancing the quality of life through wearable technology","volume":"22","author":"Park","year":"2003","journal-title":"IEEE Eng. 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