{"id":4410,"date":"2021-09-08T17:08:00","date_gmt":"2021-09-08T17:08:00","guid":{"rendered":"https:\/\/www.lasar.polimi.it\/?p=4410"},"modified":"2023-01-12T17:09:02","modified_gmt":"2023-01-12T17:09:02","slug":"new-publication-4","status":"publish","type":"post","link":"https:\/\/www.lasar.polimi.it\/?p=4410","title":{"rendered":"New Publication!"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong>Title:&nbsp;<\/strong>Metamodeling and On-Line Clustering for Loss-of-Flow Accident Precursors Identification in a Superconducting Magnet Cryogenic Cooling Circuit<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Journal:&nbsp;<\/strong>Energies<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Authors:<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Vincenzo Destino, Nicola Pedroni,&nbsp;Roberto Bonifetto,&nbsp;Francesco Di Maio,&nbsp;Laura Savoldi&nbsp;and&nbsp;Enrico Zio<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is an open-access article that can be downloaded from the following link:&nbsp;<a href=\"https:\/\/www.mdpi.com\/1996-1073\/14\/17\/5552\/pdf\">https:\/\/www.mdpi.com\/1996-1073\/14\/17\/5552\/pdf<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Abstract:<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In the International Thermonuclear Experimental Reactor, plasma is magnetically confined with Superconductive Magnets (SMs) that must be maintained at the cryogenic temperature of 4.5 K by one or more Superconducting Magnet Cryogenic Cooling Circuits (SMCCC). To guarantee cooling, Loss-of-Flow Accidents (LOFAs) in the SMCCC are to be avoided. In this work, we develop a three-step methodology for the prompt detection of LOFA precursors (i.e., those combinations of component failures causing a LOFA). First, we randomly generate accident scenarios by Monte Carlo sampling of the failures of typical SMCCC components and simulate the corresponding transient system response by a deterministic thermal-hydraulic code. In this phase, we also employ quick-running Proper Orthogonal Decomposition (POD)-based Kriging metamodels, adaptively trained to reproduce the output of the long-running code, to decrease the computational time. Second, we group the generated scenarios by a Spectral Clustering (SC) employing the Fuzzy C-Means (FCM), in order to identify the main patterns of system evolution towards abnormal states (e.g., a LOFA). Third, we develop an On-line Supervised Spectral Clustering (OSSC) technique to associate time-varying parameters measured during plant functioning to one of the prototypical groups obtained, which may highlight the related LOFA precursors (in terms of SMCCC components failures). We apply the proposed technique to the simplified model of a cryogenic cooling circuit of a single module of the ITER Central Solenoid Magnet (CSM). The framework developed promptly detects 95% of LOFA events and around 80% of the related precursors.<\/p>\n<div class=\"pvc_clear\"><\/div><p id=\"pvc_stats_4410\" class=\"pvc_stats all  \" data-element-id=\"4410\" style=\"\"><i class=\"pvc-stats-icon medium\" aria-hidden=\"true\"><svg aria-hidden=\"true\" focusable=\"false\" data-prefix=\"far\" data-icon=\"chart-bar\" role=\"img\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 512 512\" class=\"svg-inline--fa fa-chart-bar fa-w-16 fa-2x\"><path fill=\"currentColor\" d=\"M396.8 352h22.4c6.4 0 12.8-6.4 12.8-12.8V108.8c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v230.4c0 6.4 6.4 12.8 12.8 12.8zm-192 0h22.4c6.4 0 12.8-6.4 12.8-12.8V140.8c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v198.4c0 6.4 6.4 12.8 12.8 12.8zm96 0h22.4c6.4 0 12.8-6.4 12.8-12.8V204.8c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v134.4c0 6.4 6.4 12.8 12.8 12.8zM496 400H48V80c0-8.84-7.16-16-16-16H16C7.16 64 0 71.16 0 80v336c0 17.67 14.33 32 32 32h464c8.84 0 16-7.16 16-16v-16c0-8.84-7.16-16-16-16zm-387.2-48h22.4c6.4 0 12.8-6.4 12.8-12.8v-70.4c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v70.4c0 6.4 6.4 12.8 12.8 12.8z\" class=\"\"><\/path><\/svg><\/i> <img loading=\"lazy\" decoding=\"async\" width=\"16\" height=\"16\" alt=\"Loading\" src=\"https:\/\/www.lasar.polimi.it\/wp-content\/plugins\/page-views-count\/ajax-loader-2x.gif\" border=0 \/><\/p><div class=\"pvc_clear\"><\/div>","protected":false},"excerpt":{"rendered":"<p>Title:&nbsp;Metamodeling and On-Line Clustering for Loss-of-Flow Accident Precursors Identification in a Superconducting Magnet Cryogenic Cooling Circuit Journal:&nbsp;Energies Authors: Vincenzo Destino, Nicola Pedroni,&nbsp;Roberto Bonifetto,&nbsp;Francesco Di Maio,&nbsp;Laura Savoldi&nbsp;and&nbsp;Enrico Zio This is an open-access article that can be downloaded from the following link:&nbsp;https:\/\/www.mdpi.com\/1996-1073\/14\/17\/5552\/pdf Abstract: In the International Thermonuclear Experimental Reactor, plasma is magnetically [&hellip;]<\/p>\n<div class=\"pvc_clear\"><\/div>\n<p id=\"pvc_stats_4410\" class=\"pvc_stats all  \" data-element-id=\"4410\" style=\"\"><i class=\"pvc-stats-icon medium\" aria-hidden=\"true\"><svg aria-hidden=\"true\" focusable=\"false\" data-prefix=\"far\" data-icon=\"chart-bar\" role=\"img\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 512 512\" class=\"svg-inline--fa fa-chart-bar fa-w-16 fa-2x\"><path fill=\"currentColor\" d=\"M396.8 352h22.4c6.4 0 12.8-6.4 12.8-12.8V108.8c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v230.4c0 6.4 6.4 12.8 12.8 12.8zm-192 0h22.4c6.4 0 12.8-6.4 12.8-12.8V140.8c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v198.4c0 6.4 6.4 12.8 12.8 12.8zm96 0h22.4c6.4 0 12.8-6.4 12.8-12.8V204.8c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v134.4c0 6.4 6.4 12.8 12.8 12.8zM496 400H48V80c0-8.84-7.16-16-16-16H16C7.16 64 0 71.16 0 80v336c0 17.67 14.33 32 32 32h464c8.84 0 16-7.16 16-16v-16c0-8.84-7.16-16-16-16zm-387.2-48h22.4c6.4 0 12.8-6.4 12.8-12.8v-70.4c0-6.4-6.4-12.8-12.8-12.8h-22.4c-6.4 0-12.8 6.4-12.8 12.8v70.4c0 6.4 6.4 12.8 12.8 12.8z\" class=\"\"><\/path><\/svg><\/i> <img loading=\"lazy\" decoding=\"async\" width=\"16\" height=\"16\" alt=\"Loading\" src=\"https:\/\/www.lasar.polimi.it\/wp-content\/plugins\/page-views-count\/ajax-loader-2x.gif\" border=0 \/><\/p>\n<div class=\"pvc_clear\"><\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-4410","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"a3_pvc":{"activated":true,"total_views":19,"today_views":0},"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=\/wp\/v2\/posts\/4410","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4410"}],"version-history":[{"count":1,"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=\/wp\/v2\/posts\/4410\/revisions"}],"predecessor-version":[{"id":4411,"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=\/wp\/v2\/posts\/4410\/revisions\/4411"}],"wp:attachment":[{"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4410"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4410"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lasar.polimi.it\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4410"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}