{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:42:53Z","timestamp":1787028173036,"version":"3.56.0"},"reference-count":45,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,18]],"date-time":"2025-09-18T00:00:00Z","timestamp":1758153600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Instituto Politecnico Nacional","award":["20253465"],"award-info":[{"award-number":["20253465"]}]},{"name":"Instituto Politecnico Nacional","award":["20250123"],"award-info":[{"award-number":["20250123"]}]},{"name":"Instituto Politecnico Nacional","award":["20251352"],"award-info":[{"award-number":["20251352"]}]},{"name":"Instituto Politecnico Nacional","award":["CF-2023-I-722"],"award-info":[{"award-number":["CF-2023-I-722"]}]},{"name":"Secretaria de Ciencia, Humanidades, Tecnologia e Innovacion","award":["20253465"],"award-info":[{"award-number":["20253465"]}]},{"name":"Secretaria de Ciencia, Humanidades, Tecnologia e Innovacion","award":["20250123"],"award-info":[{"award-number":["20250123"]}]},{"name":"Secretaria de Ciencia, Humanidades, Tecnologia e Innovacion","award":["20251352"],"award-info":[{"award-number":["20251352"]}]},{"name":"Secretaria de Ciencia, Humanidades, Tecnologia e Innovacion","award":["CF-2023-I-722"],"award-info":[{"award-number":["CF-2023-I-722"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>A straightforward methodology for identifying certain classes of chaotic systems based on a novel version of the least-squares method, assuming they are algebraically observable and identifiable with respect to a measurable output, is introduced. This output allows us to express the original system as a chain of integrators, where the last term, which depends on the output and its corresponding time derivatives, lumps the system\u2019s non-linearities. We can factorize this term into a regressor function multiplied by an unknown-parameter vector, suggesting that a high-gain observer can be used to simultaneously and approximately estimate the states of the pure integrator and the evolution of the lumped nonlinear term. This allows us to rewrite the original system as a linear regression equation. This configuration enables the above-mentioned least-squares method to recover the chaotic-system parameters.<\/jats:p>","DOI":"10.3390\/e27090971","type":"journal-article","created":{"date-parts":[[2025,9,18]],"date-time":"2025-09-18T12:54:26Z","timestamp":1758200066000},"page":"971","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A DREM-Based Approach for the Identification of Chaotic Systems"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3925-2435","authenticated-orcid":false,"given":"Carlos","family":"Aguilar-Ibanez","sequence":"first","affiliation":[{"name":"Centro de Investigacion en Computacion, Instituto Politecnico Nacional, Ciudad de Mexico 07738, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2258-7426","authenticated-orcid":false,"given":"Miguel S.","family":"Suarez-Castanon","sequence":"additional","affiliation":[{"name":"Escuela Superior de Computo, Instituto Politecnico Nacional, Ciudad de Mexico 07738, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5150-8635","authenticated-orcid":false,"given":"Belem","family":"Saldivar","sequence":"additional","affiliation":[{"name":"Departamento de Control Automatico, Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Ciudad de Mexico 07360, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4572-5713","authenticated-orcid":false,"given":"Jos\u00e9 E.","family":"Valdez-Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Centro de Investigacion en Computacion, Instituto Politecnico Nacional, Ciudad de Mexico 07738, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4748-4666","authenticated-orcid":false,"given":"Elo\u00edsa","family":"Garc\u00eda-Canseco","sequence":"additional","affiliation":[{"name":"Facultad de Ciencias, Universidad Autonoma de Baja California, Baja California 22860, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1509","DOI":"10.1142\/S0218127410026654","article-title":"Synchronization of chaotic oscillators by means of generalized proportional integral observers","volume":"20","year":"2010","journal-title":"Int. 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