{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:27:43Z","timestamp":1760239663330,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,29]],"date-time":"2020-12-29T00:00:00Z","timestamp":1609200000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PDE\/BDE\/114549\/2016"],"award-info":[{"award-number":["PDE\/BDE\/114549\/2016"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Drones"],"abstract":"<jats:p>TomoSim comes as part of project ATMOS, a miniaturised Differential Optical Absorption Spectroscopy (DOAS) tomographic atmospheric evaluation device, designed to fit a small drone. During the development of the project, it became necessary to write a simulation tool for system validation. TomoSim is the answer to this problem. The software has two main goals: to mathematically validate the tomographic acquisition method; and to allow some adjustments to the system before reaching final product stages. This measurement strategy was based on a drone performing a sequential trajectory and gathering projections arranged in fan beams, before using some classical tomographic methods to reconstruct a spectral image. The team tested three different reconstruction algorithms, all of which were able to produce an image, validating the team\u2019s initial assumptions regarding the trajectory and acquisition strategy. All algorithms were assessed on their computational performance and their ability for reconstructing spectral \u201cimages\u201d, using two phantoms, one of which custom made for this purpose. In the end, the team was also able to uncover certain limitations of the TomoSim approach that should be addressed before the final stages of the system.<\/jats:p>","DOI":"10.3390\/drones5010003","type":"journal-article","created":{"date-parts":[[2020,12,29]],"date-time":"2020-12-29T19:55:25Z","timestamp":1609271725000},"page":"3","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["TomoSim: A Tomographic Simulator for Differential Optical Absorption Spectroscopy"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2269-7094","authenticated-orcid":false,"given":"Rui","family":"Valente de Almeida","sequence":"first","affiliation":[{"name":"Physics Department, FCT NOVA, NOVA University of Lisbon, 2829-516 Caparica, Portugal"},{"name":"FutureCompta SA, 1495-190 Alg\u00e9s, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8048-7896","authenticated-orcid":false,"given":"Nuno","family":"Matela","sequence":"additional","affiliation":[{"name":"Biomedical Engineering and Biophysics Institute, University of Lisbon, 1749-016 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3823-1184","authenticated-orcid":false,"given":"Pedro","family":"Vieira","sequence":"additional","affiliation":[{"name":"Physics Department, FCT NOVA, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1109\/MCSE.2007.53","article-title":"IPython: A System for Interactive Scientific Computing","volume":"9","author":"Perez","year":"2007","journal-title":"Comput. 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