{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T19:23:05Z","timestamp":1771701785885,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,12,12]],"date-time":"2023-12-12T00:00:00Z","timestamp":1702339200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["BCS-1951344"],"award-info":[{"award-number":["BCS-1951344"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJGI"],"abstract":"<jats:p>This research employs a spatial optimization approach customized for addressing equitable emergency medical facility location problems through the p-dispersed-median problem (p-DIME). The p-DIME integrates two conflicting classes of spatial optimization problems, dispersion and median problems, aiming to identify the optimal locations for emergency medical facilities to achieve an equitable spatial distribution of emergency medical services (EMS) while effectively serving demand. To demonstrate the utility of the p-DIME model, we selected Gyeongsangbuk-do in South Korea, recognized as one of the most challenging areas for providing EMS to the elderly population (aged 65 and over). This challenge arises from the significant spatial disparity in the distribution of emergency medical facilities. The results of the model assessment gauge the spatial disparity of EMS, provide significantly enhanced solutions for a more equitable EMS distribution in terms of service coverage, and offer policy implications for future EMS location planning. In addition, to address the computational challenges posed by p-DIME\u2019s inherent complexity, involving mixed-integer programming, this study introduces a solution technique through constraint formulations aimed at tightening the lower bounds of the problem\u2019s solution space. The computational results confirm the effectiveness of this approach in ensuring reliable computational performance, with significant reductions in solution times, while still producing optimal solutions.<\/jats:p>","DOI":"10.3390\/ijgi12120497","type":"journal-article","created":{"date-parts":[[2023,12,12]],"date-time":"2023-12-12T11:09:30Z","timestamp":1702379370000},"page":"497","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Location Planning of Emergency Medical Facilities Using the p-Dispersed-Median Modeling Approach"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1682-1802","authenticated-orcid":false,"given":"Changwha","family":"Oh","sequence":"first","affiliation":[{"name":"Department of Geography and Sustainability, University of Tennessee at Knoxville, Knoxville, TN 37996, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4957-1379","authenticated-orcid":false,"given":"Yongwan","family":"Chun","sequence":"additional","affiliation":[{"name":"School of Economic, Political and Policy Sciences, The University of Texas at Dallas, Richardson, TX 75080, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7637-678X","authenticated-orcid":false,"given":"Hyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Geography and Sustainability, University of Tennessee at Knoxville, Knoxville, TN 37996, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"477","DOI":"10.3109\/10903127.2012.695433","article-title":"Comparison of Emergency Medical Services System Across Pan-Asian Countries: A Web-based Survey","volume":"16","author":"Shin","year":"2012","journal-title":"Prehospital Emerg. 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