{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,29]],"date-time":"2025-11-29T16:20:41Z","timestamp":1764433241231,"version":"3.41.2"},"reference-count":18,"publisher":"AIP Publishing","issue":"12","funder":[{"DOI":"10.13039\/100010687","name":"H2020 Euratom","doi-asserted-by":"publisher","award":["633053"],"award-info":[{"award-number":["633053"]}],"id":[{"id":"10.13039\/100010687","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2018,12,1]]},"abstract":"<jats:p>Wendelstein 7-X (W7-X) is the most advanced fusion experiment in the stellarator line and is aimed at proving that the stellarator concept is suitable for a fusion reactor. One of the most important issues for fusion reactors is the monitoring of plasma facing components when exposed to very high heat loads, through the use of visible and infrared (IR) cameras. In this paper, a new image processing system for the analysis of the strike lines on the inboard limiters from the first W7-X experimental campaign is presented. This system builds a model of the IR cameras through the use of spatial calibration techniques, helping to characterize the strike lines by using the information given by real spatial coordinates of each pixel. The characterization of the strike lines is made in terms of position, size, and shape, after projecting the camera image in a 2D grid which tries to preserve the curvilinear surface distances between points. The description of the strike-line shape is made by means of the Fourier Descriptors.<\/jats:p>","DOI":"10.1063\/1.5045560","type":"journal-article","created":{"date-parts":[[2018,12,13]],"date-time":"2018-12-13T19:43:42Z","timestamp":1544730222000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":14,"title":["Towards a new image processing system at Wendelstein 7-X: From spatial calibration to characterization of thermal events"],"prefix":"10.1063","volume":"89","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0162-0562","authenticated-orcid":false,"given":"F.","family":"Pisano","sequence":"first","affiliation":[{"name":"Department of Electrical and Electronic Engineering, University of Cagliari 1 , Via Marengo 2, Cagliari 09123, Italy"}]},{"given":"B.","family":"Cannas","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, University of Cagliari 1 , Via Marengo 2, Cagliari 09123, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6557-3497","authenticated-orcid":false,"given":"M. W.","family":"Jakubowski","sequence":"additional","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Plasmaphysik, Teilinstitut Greifswald 2 , Wendelsteinstra\u00dfe 1, Greifswald D-17491, Germany"},{"name":"University of Szczecin, Institute of Physics 3 , Szczecin 70-451, Poland"}]},{"given":"H.","family":"Niemann","sequence":"additional","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Plasmaphysik, Teilinstitut Greifswald 2 , Wendelsteinstra\u00dfe 1, Greifswald D-17491, Germany"}]},{"given":"A.","family":"Puig Sitjes","sequence":"additional","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Plasmaphysik, Teilinstitut Greifswald 2 , Wendelsteinstra\u00dfe 1, Greifswald D-17491, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2991-1484","authenticated-orcid":false,"given":"G. A.","family":"Wurden","sequence":"additional","affiliation":[{"name":"Los Alamos National Laboratory 4 , Los Alamos, New Mexico 87545, USA"}]},{"name":"W7-X Team","sequence":"additional","affiliation":[]}],"member":"317","published-online":{"date-parts":[[2018,12,13]]},"reference":[{"key":"2023080501170407800_c1","doi-asserted-by":"publisher","first-page":"113502","DOI":"10.1063\/1.4935580","article-title":"Real time capable infrared thermography for ASDEX upgrade","volume":"86","year":"2015","journal-title":"Rev. Sci. Instrum."},{"key":"2023080501170407800_c2","doi-asserted-by":"publisher","first-page":"10E116","DOI":"10.1063\/1.5038634","article-title":"Infrared imaging systems for wall protection in the W7-X stellarator","volume":"89","year":"2018","journal-title":"Rev. Sci. 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