{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T16:59:34Z","timestamp":1763398774300,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,17]],"date-time":"2022-12-17T00:00:00Z","timestamp":1671235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>Cork is a versatile natural material. It can be used as an insulator in construction, among many other applications. For good forest management of cork oaks, forest owners need to calculate the volume of cork periodically. This will allow them to choose the right time to harvest the cork. The traditional method is laborious and time consuming. The present work aims to automate the process of calculating the trunk area of a cork oak from which cork is extracted. Through this calculation, it will be possible to estimate the volume of cork produced before the stripping process. A deep neural network, Mask R-CNN, and a machine learning algorithm are used. A dataset of images of cork oaks was created, where targets of known dimensions were fixed on the trunks. The Mask R-CNN was trained to recognize targets cork regions, and so the area of cork was estimated based on the target dimensions. Preliminary results show that the model presents a good performance in the recognition of targets and trunks, registering a mAP@0.7 of 0.96. After obtaining the mask results, three machine learning models were trained to estimate the cork volume based on the area and biometric parameters of the tree. The results showed that a support vector machine produced an average error of 8.75%, which is within the error margins obtained using traditional methods.<\/jats:p>","DOI":"10.3390\/en15249593","type":"journal-article","created":{"date-parts":[[2022,12,19]],"date-time":"2022-12-19T09:31:01Z","timestamp":1671442261000},"page":"9593","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Cork Oak Production Estimation Using a Mask R-CNN"],"prefix":"10.3390","volume":"15","author":[{"given":"Andr\u00e9","family":"Guimar\u00e3es","sequence":"first","affiliation":[{"name":"Instituto Superior de Engenharia de Coimbra, Polytechnic of Coimbra\u2014ISEC, 3030-199 Coimbra, Portugal"}]},{"given":"Maria","family":"Val\u00e9rio","sequence":"additional","affiliation":[{"name":"School of Agriculture of Coimbra, Polytechnic of Coimbra\u2014ESAC, 3045-093 Coimbra, Portugal"}]},{"given":"Beatriz","family":"Fidalgo","sequence":"additional","affiliation":[{"name":"School of Agriculture of Coimbra, Polytechnic of Coimbra\u2014ESAC, 3045-093 Coimbra, Portugal"}]},{"given":"Ra\u00fal","family":"Salas-Gonzalez","sequence":"additional","affiliation":[{"name":"School of Agriculture of Coimbra, Polytechnic of Coimbra\u2014ESAC, 3045-093 Coimbra, Portugal"}]},{"given":"Carlos","family":"Pereira","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia de Coimbra, Polytechnic of Coimbra\u2014ISEC, 3030-199 Coimbra, Portugal"},{"name":"Departamento de Eng. Inform\u00e1tica, CISUC\u2014Centre for Informatics and Systems of the University of Coimbra, P\u00f3lo II, Rua S\u00edlvio Lima, 3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4313-7966","authenticated-orcid":false,"given":"Mateus","family":"Mendes","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia de Coimbra, Polytechnic of Coimbra\u2014ISEC, 3030-199 Coimbra, Portugal"},{"name":"Departamento de Eng. Eletrot\u00e9cnica e Computadores, ISR\u2014Institute of Systems and Robotics of the University of Coimbra, P\u00f3lo II, Rua S\u00edlvio Lima, University of Coimbra, 3030-194 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,17]]},"reference":[{"key":"ref_1","unstructured":"ICNF (2013). IFN6\u2014\u00c1reas dos usos do solo e das Esp\u00e9cies Florestais de Portugal Continental, Instituto da Conserva\u00e7\u00e3o da Natureza e das Florestas. 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