{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T21:12:37Z","timestamp":1773436357712,"version":"3.50.1"},"reference-count":56,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,10,1]],"date-time":"2019-10-01T00:00:00Z","timestamp":1569888000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This paper investigates the time to complete the boarding of a partially occupied two-door airplane when its passengers are transported from the airport terminal to the airplane using two apron buses. We propose a greedy method that assigns each passenger to a particular apron bus based on the passengers\u2019 airplane seat assignments. This greedy approach exploits the airplane\u2019s symmetry by providing essentially the same method for those boarding through the front door of the airplane as those boarding through the rear door of the airplane. The symmetrical properties of window, middle, and aisle seats of each row\/side are considered in the proposed method as well. Computer simulation results indicate that, when using the greedy method, the boarding time can be reduced by up to 8.33% compared to the boarding time resulting from the best known practices in the literature, and with up to a 43.72% improvement in boarding time when compared to the boarding method commonly used in many airports. Furthermore, experimental results confirm our hypothesis that when the capacity of the apron buses exceeds the number of passengers to be transported to the airplane, the most time-efficient results of the proposed greedy method occur when an equal number of passengers are assigned to each of the two apron buses.<\/jats:p>","DOI":"10.3390\/sym11101221","type":"journal-article","created":{"date-parts":[[2019,10,1]],"date-time":"2019-10-01T11:11:16Z","timestamp":1569928276000},"page":"1221","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Greedy Method for Boarding a Partially Occupied Airplane Using Apron Buses"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2132-1749","authenticated-orcid":false,"given":"R. John","family":"Milne","sequence":"first","affiliation":[{"name":"David D. Reh School of Business, Clarkson University, 333 B.H. Snell Hall, Potsdam, NY 13699, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4192-183X","authenticated-orcid":false,"given":"Liviu-Adrian","family":"Cotfas","sequence":"additional","affiliation":[{"name":"Department of Economic Informatics and Cybernetics, Bucharest University of Economic Studies, 010552 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3589-1969","authenticated-orcid":false,"given":"Camelia","family":"Delcea","sequence":"additional","affiliation":[{"name":"Department of Economic Informatics and Cybernetics, Bucharest University of Economic Studies, 010552 Bucharest, Romania"}]},{"given":"Mostafa","family":"Salari","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada"}]},{"given":"Liliana","family":"Craciun","sequence":"additional","affiliation":[{"name":"Department of Economics and Economic Policies, Bucharest University of Economic Studies, 010374 Bucharest, Romania"}]},{"given":"Anca Gabriela","family":"Molanescu","sequence":"additional","affiliation":[{"name":"Department of Economics and Economic Policies, Bucharest University of Economic Studies, 010374 Bucharest, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Doganis, P.R., and Doganis, R. 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