{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:02:20Z","timestamp":1760238140029,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2020,7,23]],"date-time":"2020-07-23T00:00:00Z","timestamp":1595462400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001321","name":"National Research Foundation","doi-asserted-by":"publisher","award":["2020R1A2C3006786"],"award-info":[{"award-number":["2020R1A2C3006786"]}],"id":[{"id":"10.13039\/501100001321","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Time synchronization is an essential issue in industrial wireless sensor networks (IWSNs). It assists perfect coordinated communications among the sensor nodes to preserve battery power. Generally, time synchronization in IWSNs has two major aspects of energy consumption and accuracy. In the literature, the energy consumption has not received much attention in contrast to the accuracy. In this paper, focusing on the energy consumption aspect, we introduce an energy-efficient reference node selection (EERS) algorithm for time synchronization in IWSNs. It selects and schedules a minimal sequence of connected reference nodes that are responsible for spreading timing messages. EERS achieves energy consumption synchronization by reducing the number of transmitted messages among the sensor nodes. To evaluate the performance of EERS, we conducted extensive experiments with Arduino Nano RF sensors and revealed that EERS achieves considerably fewer messages than previous techniques, robust time synchronization (R-Sync), fast scheduling and accurate drift compensation for time synchronization (FADS), and low power scheduling for time synchronization protocols (LPSS). In addition, simulation results for a large sensor network of 450 nodes demonstrate that EERS reduces the whole number of transmitted messages by 52%, 30%, and 13% compared to R-Sync, FADS, and LPSS, respectively.<\/jats:p>","DOI":"10.3390\/s20154095","type":"journal-article","created":{"date-parts":[[2020,7,23]],"date-time":"2020-07-23T11:26:01Z","timestamp":1595503561000},"page":"4095","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["EERS: Energy-Efficient Reference Node Selection Algorithm for Synchronization in Industrial Wireless Sensor Networks"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3037-6792","authenticated-orcid":false,"given":"Mahmoud","family":"Elsharief","sequence":"first","affiliation":[{"name":"School of Electrical Engineering, Korea University, Seoul 02841, Korea"}]},{"given":"Mohamed A. Abd","family":"El-Gawad","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Korea University, Seoul 02841, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9067-445X","authenticated-orcid":false,"given":"Haneul","family":"Ko","sequence":"additional","affiliation":[{"name":"Department of Computer Convergence Software, Korea University, Sejong 30019, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1085-1568","authenticated-orcid":false,"given":"Sangheon","family":"Pack","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Korea University, Seoul 02841, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"978","DOI":"10.1109\/COMST.2017.2780114","article-title":"Wireless Network Design for Control Systems: A Survey","volume":"20","author":"Park","year":"2018","journal-title":"IEEE Commun. Surv. 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