{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T04:02:42Z","timestamp":1773288162545,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2016,7,28]],"date-time":"2016-07-28T00:00:00Z","timestamp":1469664000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>We report experimental observations on the evolution of acoustic entropy in the course of cyclic loading as degradation occurs due to fatigue. The measured entropy is a result of the materials\u2019 microstructural changes that occur as degradation due to cyclic mechanical loading. Experimental results demonstrate that maximum acoustic entropy emanating from materials during the course of degradation remains similar. Experiments are shown for two different types of materials: Aluminum 6061 (a metallic alloy) and glass\/epoxy (a composite laminate). The evolution of the acoustic entropy demonstrates a persistent trend over the course of degradation.<\/jats:p>","DOI":"10.3390\/e18080280","type":"journal-article","created":{"date-parts":[[2016,7,28]],"date-time":"2016-07-28T10:04:56Z","timestamp":1469700296000},"page":"280","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Acoustic Entropy of the Materials in the Course of Degradation"],"prefix":"10.3390","volume":"18","author":[{"given":"Ali","family":"Kahirdeh","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Louisiana State University, Baton Rouge, LA 70803, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"M.","family":"Khonsari","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Louisiana State University, Baton Rouge, LA 70803, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,7,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2435","DOI":"10.1016\/j.jmps.2005.06.004","article-title":"Prediction scheme for the catastrophic failure of highly loaded brittle materials or rocks","volume":"53","author":"Moura","year":"2005","journal-title":"J. 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