{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T09:21:39Z","timestamp":1778059299541,"version":"3.51.4"},"reference-count":43,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2019,12,14]],"date-time":"2019-12-14T00:00:00Z","timestamp":1576281600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["01.2.2-LMT-K-718"],"award-info":[{"award-number":["01.2.2-LMT-K-718"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The purpose of this study is to introduce an improved Luedeking\u2013Piret model that represents a structurally simple biomass concentration approach. The developed routine provides acceptable accuracy when fitting experimental data that incorporate the target protein concentration of Escherichia coli culture BL21 (DE3) pET28a in fed-batch processes. This paper presents system identification, biomass, and product parameter fitting routines, starting from their roots of origin to the entropy-related development, characterized by robustness and simplicity. A single tuning coefficient allows for the selection of an optimization criterion that serves equally well for higher and lower biomass concentrations. The idea of the paper is to demonstrate that the use of fundamental knowledge can make the general model more common for technological use compared to a sophisticated artificial neural network. Experimental validation of the proposed model involved data analysis of six cultivation experiments compared to 19 experiments used for model fitting and parameter estimation.<\/jats:p>","DOI":"10.3390\/e21121221","type":"journal-article","created":{"date-parts":[[2019,12,17]],"date-time":"2019-12-17T02:59:01Z","timestamp":1576551541000},"page":"1221","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Identification of Functional Bioprocess Model for Recombinant E. Coli Cultivation Process"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8095-890X","authenticated-orcid":false,"given":"Renaldas","family":"Urniezius","sequence":"first","affiliation":[{"name":"Department of Automation, Kaunas University of Technology, Kaunas LT-51367, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arnas","family":"Survyla","sequence":"additional","affiliation":[{"name":"Department of Automation, Kaunas University of Technology, Kaunas LT-51367, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/S1367-5788(00)00012-2","article-title":"Predicting the performance of soft sensors as a route to low cost automation","volume":"24","author":"Goodwin","year":"2000","journal-title":"Annu. Rev. 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