{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:31:42Z","timestamp":1760059902810,"version":"build-2065373602"},"reference-count":18,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,7,18]],"date-time":"2025-07-18T00:00:00Z","timestamp":1752796800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Faculdade de Ci\u00eancias, Universidade de Lisboa","award":["UIDB\/04621\/2020","UIDP\/04621\/2020"],"award-info":[{"award-number":["UIDB\/04621\/2020","UIDP\/04621\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["AppliedMath"],"abstract":"<jats:p>Hydropressor systems are of paramount importance in keeping water supplies running properly. A typical such device consists of two (or more) identical electropumps operating alternately, so as to avoid downtime as much as possible. We consider a dual pump configuration to identify the ideal usage proportion of each pump (from 0%-100%, meaning interchange only upon failure, to 50%-50%, where each pump works half the time) in order to improve availability, accounting solely for corrective maintenance. We also address the possibility of improving the availability of a single pump under the hazard of failure in three different ways (with their own occurrence frequencies), while also accounting for preventive maintenance. Both settings are tackled through Monte Carlo simulation and the models are implemented with the Python 3.12 programming language. The results indicate that significant improvements to standard industry practices can be made.<\/jats:p>","DOI":"10.3390\/appliedmath5030094","type":"journal-article","created":{"date-parts":[[2025,7,18]],"date-time":"2025-07-18T15:35:51Z","timestamp":1752852951000},"page":"94","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Availability of Hydropressor Systems: Redundancy and Multiple Failure Modes"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3407-7757","authenticated-orcid":false,"given":"Ricardo","family":"Engui\u00e7a","sequence":"first","affiliation":[{"name":"Departmento de Matem\u00e1tica, ISEL\u2014Instituto Superior de Engenharia de Lisboa, Rua Conselheiro Em\u00eddio Navarro, 1, 1959-007 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6853-6854","authenticated-orcid":false,"given":"S\u00e9rgio","family":"Lopes","sequence":"additional","affiliation":[{"name":"Departmento de Matem\u00e1tica, ISEL\u2014Instituto Superior de Engenharia de Lisboa, Rua Conselheiro Em\u00eddio Navarro, 1, 1959-007 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rubinstein, R., and Kroese, D. (2016). Simulation and the Monte Carlo Method, Wiley. [3rd ed.].","DOI":"10.1002\/9781118631980"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Rausand, M., Barros, A., and Hoyland, A. (2020). System Reliability Theory: Models, Statistical Methods, and Applications, Wiley. [3rd ed.].","DOI":"10.1002\/9781119373940"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Hashemi, M., Tavangar, M., and Asadi, M. (2021). Optimal preventive maintenance for coherent systems whose failure occurs due to ageing or external shocks. Comput. Ind. Eng., 163.","DOI":"10.1016\/j.cie.2021.107829"},{"key":"ref_4","unstructured":"Mercier, S. (2001, January 12\u201315). Optimization of the Corrective Maintenance of a Repairable System. 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Using the Weibull Distribution: Reliability, Modeling, and Inference, Wiley.","DOI":"10.1002\/9781118351994"}],"container-title":["AppliedMath"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2673-9909\/5\/3\/94\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:12:26Z","timestamp":1760033546000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2673-9909\/5\/3\/94"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,18]]},"references-count":18,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["appliedmath5030094"],"URL":"https:\/\/doi.org\/10.3390\/appliedmath5030094","relation":{},"ISSN":["2673-9909"],"issn-type":[{"type":"electronic","value":"2673-9909"}],"subject":[],"published":{"date-parts":[[2025,7,18]]}}}