{"id":"https://openalex.org/W4408820312","doi":"https://doi.org/10.3390/make7020027","title":"On Classification of the Human Emotions from Facial Thermal Images: A Case Study Based on Machine Learning","display_name":"On Classification of the Human Emotions from Facial Thermal Images: A Case Study Based on Machine Learning","publication_year":2025,"publication_date":"2025-03-25","ids":{"openalex":"https://openalex.org/W4408820312","doi":"https://doi.org/10.3390/make7020027"},"language":"en","primary_location":{"id":"doi:10.3390/make7020027","is_oa":true,"landing_page_url":"https://doi.org/10.3390/make7020027","pdf_url":"https://www.mdpi.com/2504-4990/7/2/27/pdf?version=1742905203","source":{"id":"https://openalex.org/S4210213891","display_name":"Machine Learning and Knowledge Extraction","issn_l":"2504-4990","issn":["2504-4990"],"is_oa":true,"is_in_doaj":true,"is_core":true,"host_organization":"https://openalex.org/P4310310987","host_organization_name":"Multidisciplinary Digital Publishing Institute","host_organization_lineage":["https://openalex.org/P4310310987"],"host_organization_lineage_names":["Multidisciplinary Digital Publishing Institute"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Machine Learning and Knowledge Extraction","raw_type":"journal-article"},"type":"article","indexed_in":["crossref","doaj"],"open_access":{"is_oa":true,"oa_status":"gold","oa_url":"https://www.mdpi.com/2504-4990/7/2/27/pdf?version=1742905203","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5048731251","display_name":"Marius Sorin Pavel","orcid":null},"institutions":[{"id":"https://openalex.org/I3122748864","display_name":"\"Dunarea de Jos\" University of Galati","ror":"https://ror.org/052sta926","country_code":"RO","type":"education","lineage":["https://openalex.org/I3122748864"]}],"countries":["RO"],"is_corresponding":true,"raw_author_name":"Marius Pavel","raw_affiliation_strings":["Department of Electronics and Telecommunications, Faculty of Automation, Computers, Electrical Engineering and Electronics, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Electronics and Telecommunications, Faculty of Automation, Computers, Electrical Engineering and Electronics, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania","institution_ids":["https://openalex.org/I3122748864"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5082973301","display_name":"Simona Moldovanu","orcid":"https://orcid.org/0000-0002-5934-329X"},"institutions":[{"id":"https://openalex.org/I3122748864","display_name":"\"Dunarea de Jos\" University of Galati","ror":"https://ror.org/052sta926","country_code":"RO","type":"education","lineage":["https://openalex.org/I3122748864"]}],"countries":["RO"],"is_corresponding":false,"raw_author_name":"Simona Moldovanu","raw_affiliation_strings":["Department of Computer Science and Information Technology, Faculty of Automation, Computers, Electrical Engineering and Electronics, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania"],"raw_orcid":"https://orcid.org/0000-0002-5934-329X","affiliations":[{"raw_affiliation_string":"Department of Computer Science and Information Technology, Faculty of Automation, Computers, Electrical Engineering and Electronics, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania","institution_ids":["https://openalex.org/I3122748864"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5019092446","display_name":"Dorel Aiord\u0103chioaie","orcid":"https://orcid.org/0000-0001-9752-9629"},"institutions":[{"id":"https://openalex.org/I3122748864","display_name":"\"Dunarea de Jos\" University of Galati","ror":"https://ror.org/052sta926","country_code":"RO","type":"education","lineage":["https://openalex.org/I3122748864"]}],"countries":["RO"],"is_corresponding":false,"raw_author_name":"Dorel Aiordachioaie","raw_affiliation_strings":["Department of Electronics and Telecommunications, Faculty of Automation, Computers, Electrical Engineering and Electronics, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania"],"raw_orcid":"https://orcid.org/0000-0001-9752-9629","affiliations":[{"raw_affiliation_string":"Department of Electronics and Telecommunications, Faculty of Automation, Computers, Electrical Engineering and Electronics, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania","institution_ids":["https://openalex.org/I3122748864"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":3,"corresponding_author_ids":["https://openalex.org/A5048731251"],"corresponding_institution_ids":["https://openalex.org/I3122748864"],"apc_list":{"value":1400,"currency":"CHF","value_usd":1515},"apc_paid":{"value":1400,"currency":"CHF","value_usd":1515},"fwci":7.7271,"has_fulltext":false,"cited_by_count":7,"citation_normalized_percentile":{"value":0.97383848,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":96,"max":99},"biblio":{"volume":"7","issue":"2","first_page":"27","last_page":"27"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T12994","display_name":"Infrared Thermography in Medicine","score":0.996399998664856,"subfield":{"id":"https://openalex.org/subfields/2741","display_name":"Radiology, Nuclear Medicine and Imaging"},"field":{"id":"https://openalex.org/fields/27","display_name":"Medicine"},"domain":{"id":"https://openalex.org/domains/4","display_name":"Health Sciences"}},"topics":[{"id":"https://openalex.org/T12994","display_name":"Infrared Thermography in Medicine","score":0.996399998664856,"subfield":{"id":"https://openalex.org/subfields/2741","display_name":"Radiology, Nuclear Medicine and Imaging"},"field":{"id":"https://openalex.org/fields/27","display_name":"Medicine"},"domain":{"id":"https://openalex.org/domains/4","display_name":"Health Sciences"}},{"id":"https://openalex.org/T14512","display_name":"Technology and Human Factors in Education and Health","score":0.9537000060081482,"subfield":{"id":"https://openalex.org/subfields/2739","display_name":"Public Health, Environmental and Occupational Health"},"field":{"id":"https://openalex.org/fields/27","display_name":"Medicine"},"domain":{"id":"https://openalex.org/domains/4","display_name":"Health Sciences"}},{"id":"https://openalex.org/T12647","display_name":"Traditional Chinese Medicine Studies","score":0.9509000182151794,"subfield":{"id":"https://openalex.org/subfields/2707","display_name":"Complementary and alternative medicine"},"field":{"id":"https://openalex.org/fields/27","display_name":"Medicine"},"domain":{"id":"https://openalex.org/domains/4","display_name":"Health Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/artificial-intelligence","display_name":"Artificial intelligence","score":0.773249626159668},{"id":"https://openalex.org/keywords/support-vector-machine","display_name":"Support vector machine","score":0.7453755140304565},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.7162966728210449},{"id":"https://openalex.org/keywords/convolutional-neural-network","display_name":"Convolutional neural network","score":0.597470760345459},{"id":"https://openalex.org/keywords/noise","display_name":"Noise (video)","score":0.5315883755683899},{"id":"https://openalex.org/keywords/pattern-recognition","display_name":"Pattern recognition (psychology)","score":0.5089128017425537},{"id":"https://openalex.org/keywords/field","display_name":"Field (mathematics)","score":0.4890681207180023},{"id":"https://openalex.org/keywords/multiclass-classification","display_name":"Multiclass classification","score":0.4880434572696686},{"id":"https://openalex.org/keywords/random-forest","display_name":"Random forest","score":0.4562176465988159},{"id":"https://openalex.org/keywords/machine-learning","display_name":"Machine learning","score":0.43899115920066833},{"id":"https://openalex.org/keywords/process","display_name":"Process (computing)","score":0.42526674270629883},{"id":"https://openalex.org/keywords/image","display_name":"Image (mathematics)","score":0.2689359784126282},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.1870916187763214}],"concepts":[{"id":"https://openalex.org/C154945302","wikidata":"https://www.wikidata.org/wiki/Q11660","display_name":"Artificial intelligence","level":1,"score":0.773249626159668},{"id":"https://openalex.org/C12267149","wikidata":"https://www.wikidata.org/wiki/Q282453","display_name":"Support vector machine","level":2,"score":0.7453755140304565},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.7162966728210449},{"id":"https://openalex.org/C81363708","wikidata":"https://www.wikidata.org/wiki/Q17084460","display_name":"Convolutional neural network","level":2,"score":0.597470760345459},{"id":"https://openalex.org/C99498987","wikidata":"https://www.wikidata.org/wiki/Q2210247","display_name":"Noise (video)","level":3,"score":0.5315883755683899},{"id":"https://openalex.org/C153180895","wikidata":"https://www.wikidata.org/wiki/Q7148389","display_name":"Pattern recognition (psychology)","level":2,"score":0.5089128017425537},{"id":"https://openalex.org/C9652623","wikidata":"https://www.wikidata.org/wiki/Q190109","display_name":"Field (mathematics)","level":2,"score":0.4890681207180023},{"id":"https://openalex.org/C123860398","wikidata":"https://www.wikidata.org/wiki/Q6934605","display_name":"Multiclass classification","level":3,"score":0.4880434572696686},{"id":"https://openalex.org/C169258074","wikidata":"https://www.wikidata.org/wiki/Q245748","display_name":"Random forest","level":2,"score":0.4562176465988159},{"id":"https://openalex.org/C119857082","wikidata":"https://www.wikidata.org/wiki/Q2539","display_name":"Machine learning","level":1,"score":0.43899115920066833},{"id":"https://openalex.org/C98045186","wikidata":"https://www.wikidata.org/wiki/Q205663","display_name":"Process (computing)","level":2,"score":0.42526674270629883},{"id":"https://openalex.org/C115961682","wikidata":"https://www.wikidata.org/wiki/Q860623","display_name":"Image (mathematics)","level":2,"score":0.2689359784126282},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.1870916187763214},{"id":"https://openalex.org/C111919701","wikidata":"https://www.wikidata.org/wiki/Q9135","display_name":"Operating system","level":1,"score":0.0},{"id":"https://openalex.org/C202444582","wikidata":"https://www.wikidata.org/wiki/Q837863","display_name":"Pure mathematics","level":1,"score":0.0}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.3390/make7020027","is_oa":true,"landing_page_url":"https://doi.org/10.3390/make7020027","pdf_url":"https://www.mdpi.com/2504-4990/7/2/27/pdf?version=1742905203","source":{"id":"https://openalex.org/S4210213891","display_name":"Machine Learning and Knowledge Extraction","issn_l":"2504-4990","issn":["2504-4990"],"is_oa":true,"is_in_doaj":true,"is_core":true,"host_organization":"https://openalex.org/P4310310987","host_organization_name":"Multidisciplinary Digital Publishing Institute","host_organization_lineage":["https://openalex.org/P4310310987"],"host_organization_lineage_names":["Multidisciplinary Digital Publishing Institute"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Machine Learning and Knowledge Extraction","raw_type":"journal-article"},{"id":"pmh:oai:doaj.org/article:8b4095e4d8da450ead706e9857675a22","is_oa":true,"landing_page_url":"https://doaj.org/article/8b4095e4d8da450ead706e9857675a22","pdf_url":null,"source":{"id":"https://openalex.org/S4306401280","display_name":"DOAJ (DOAJ: Directory of Open Access Journals)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":null,"host_organization_name":null,"host_organization_lineage":[],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by-sa","license_id":"https://openalex.org/licenses/cc-by-sa","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"Machine Learning and Knowledge Extraction, Vol 7, Iss 2, p 27 (2025)","raw_type":"article"}],"best_oa_location":{"id":"doi:10.3390/make7020027","is_oa":true,"landing_page_url":"https://doi.org/10.3390/make7020027","pdf_url":"https://www.mdpi.com/2504-4990/7/2/27/pdf?version=1742905203","source":{"id":"https://openalex.org/S4210213891","display_name":"Machine Learning and Knowledge Extraction","issn_l":"2504-4990","issn":["2504-4990"],"is_oa":true,"is_in_doaj":true,"is_core":true,"host_organization":"https://openalex.org/P4310310987","host_organization_name":"Multidisciplinary Digital Publishing Institute","host_organization_lineage":["https://openalex.org/P4310310987"],"host_organization_lineage_names":["Multidisciplinary Digital Publishing Institute"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Machine Learning and Knowledge Extraction","raw_type":"journal-article"},"sustainable_development_goals":[{"id":"https://metadata.un.org/sdg/15","display_name":"Life in Land","score":0.41999998688697815}],"awards":[],"funders":[],"has_content":{"pdf":true,"grobid_xml":false},"content_urls":{"pdf":"https://content.openalex.org/works/W4408820312.pdf"},"referenced_works_count":62,"referenced_works":["https://openalex.org/W2012284677","https://openalex.org/W2088553141","https://openalex.org/W2091403031","https://openalex.org/W2127038386","https://openalex.org/W2132148016","https://openalex.org/W2135220085","https://openalex.org/W2156158655","https://openalex.org/W2162244427","https://openalex.org/W2227023164","https://openalex.org/W2341635611","https://openalex.org/W2346323058","https://openalex.org/W2465311012","https://openalex.org/W2482241782","https://openalex.org/W2518326618","https://openalex.org/W2745346281","https://openalex.org/W2885426888","https://openalex.org/W2902038035","https://openalex.org/W2917629381","https://openalex.org/W2936712672","https://openalex.org/W2941733427","https://openalex.org/W2945731770","https://openalex.org/W2964370293","https://openalex.org/W2981093889","https://openalex.org/W2982163280","https://openalex.org/W2995036875","https://openalex.org/W2999473554","https://openalex.org/W3021046219","https://openalex.org/W3039930096","https://openalex.org/W3041390796","https://openalex.org/W3043008108","https://openalex.org/W3048297990","https://openalex.org/W3094449569","https://openalex.org/W3104042626","https://openalex.org/W3120409033","https://openalex.org/W3129610754","https://openalex.org/W3157429286","https://openalex.org/W3167245633","https://openalex.org/W3190725526","https://openalex.org/W3198298271","https://openalex.org/W4205349001","https://openalex.org/W4207061843","https://openalex.org/W4246849106","https://openalex.org/W4250534264","https://openalex.org/W4252881731","https://openalex.org/W4292387409","https://openalex.org/W4312062097","https://openalex.org/W4312723656","https://openalex.org/W4360611419","https://openalex.org/W4366256595","https://openalex.org/W4382139365","https://openalex.org/W4385618369","https://openalex.org/W4385804938","https://openalex.org/W4387583551","https://openalex.org/W4388623216","https://openalex.org/W4391733623","https://openalex.org/W4393008246","https://openalex.org/W4397030809","https://openalex.org/W6672531436","https://openalex.org/W6681659228","https://openalex.org/W6726380845","https://openalex.org/W6773494538","https://openalex.org/W6806819144"],"related_works":["https://openalex.org/W4396689146","https://openalex.org/W4200112873","https://openalex.org/W2955796858","https://openalex.org/W2004826645","https://openalex.org/W4372048956","https://openalex.org/W2039745824","https://openalex.org/W3157224608","https://openalex.org/W2924823884","https://openalex.org/W2623163150","https://openalex.org/W2186666570"],"abstract_inverted_index":{"(1)":[0],"Background:":[1],"This":[2],"paper":[3,44,173],"intends":[4],"to":[5,25,95,102,181,240],"accomplish":[6],"a":[7,36,48,207,243],"comparative":[8,37],"study":[9],"and":[10,31,75,79,125,151,156,219,231],"analysis":[11],"regarding":[12],"the":[13,39,43,57,68,96,103,106,115,160,175,182,190,214,220,232,236,247],"multiclass":[14,130],"classification":[15,131,208,249],"of":[16,42,63,105,118,138,178,184,193,210,217,235],"facial":[17,194],"thermal":[18,195],"images,":[19,120,218],"i.e.,":[20,70,121,140],"in":[21,46,67,171],"three":[22,221],"classes":[23,223],"corresponding":[24,222],"predefined":[26],"emotional":[27],"states":[28],"(neutral,":[29],"happy":[30],"sad).":[32],"By":[33],"carrying":[34],"out":[35],"analysis,":[38],"main":[40],"goal":[41],"consists":[45],"identifying":[47],"suitable":[49],"algorithm":[50],"from":[51,85],"machine":[52,141],"learning":[53,142,158],"field,":[54],"which":[55],"has":[56],"highest":[58],"accuracy":[59,209],"(ACC).":[60],"Two":[61],"categories":[62,192,216],"images":[64,71,76,99,196],"were":[65,203],"used":[66,200],"process,":[69],"with":[72,77,109,143,159,174,189,197],"Gaussian":[73],"noise":[74,82,199],"\u201csalt":[78],"pepper\u201d":[80],"type":[81],"that":[83,100],"come":[84],"two":[86,107,136,176,191,215],"built-in":[87],"special":[88],"databases.":[89],"An":[90],"augmentation":[91,117],"process":[92,132],"was":[93,133],"applied":[94],"initial":[97],"raw":[98],"led":[101],"development":[104],"databases":[108,230],"added":[110,198],"noise,":[111],"as":[112,114,201],"well":[113],"subsequent":[116],"all":[119],"rotation,":[122],"reflection,":[123],"translation":[124],"scaling.":[126],"(2)":[127],"Methods:":[128],"The":[129,168,228],"implemented":[134,237],"through":[135],"subsets":[137,177],"methods,":[139],"random":[144],"forest":[145],"(RF),":[146],"support":[147],"vector":[148],"machines":[149],"(SVM)":[150],"k-nearest":[152],"neighbor":[153],"(KNN)":[154],"algorithms":[155,238],"deep":[157],"convolutional":[161],"neural":[162],"network":[163],"(CNN)":[164],"algorithm.":[165],"(3)":[166],"Results:":[167],"results":[169],"obtained":[170],"this":[172],"methods":[179],"belonging":[180],"field":[183],"artificial":[185],"intelligence":[186],"(AI),":[187],"together":[188],"input,":[202],"very":[204],"good,":[205],"showing":[206],"over":[211],"99%":[212],"for":[213,224],"each.":[225],"(4)":[226],"Discussion:":[227],"augmented":[229],"additional":[233],"configurations":[234],"seems":[239],"have":[241],"had":[242],"positive":[244],"effect":[245],"on":[246],"final":[248],"results.":[250]},"counts_by_year":[{"year":2026,"cited_by_count":4},{"year":2025,"cited_by_count":3}],"updated_date":"2026-05-21T06:26:12.895304","created_date":"2025-10-10T00:00:00"}
