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In this paper, facial expressions of a humanoid robot are modeled depending on the degrees of the emotions. Larger degree of emotion causes a stronger indicator of the facial mimic.<\/jats:p>","DOI":"10.3233\/jifs-189114","type":"journal-article","created":{"date-parts":[[2020,8,11]],"date-time":"2020-08-11T14:30:07Z","timestamp":1597156207000},"page":"6507-6515","source":"Crossref","is-referenced-by-count":5,"title":["Modeling humanoid robots facial expressions using Pythagorean fuzzy sets"],"prefix":"10.1177","volume":"39","author":[{"given":"Cengiz","family":"Kahraman","sequence":"first","affiliation":[{"name":"Department of Industrial Engineering, \u0130stanbul Technical University, \u0130stanbul, Turkey"}]},{"given":"Eda","family":"Bolt\u00fcrk","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, \u0130stanbul Technical University, \u0130stanbul, Turkey"}]},{"given":"Sezi Cevik","family":"Onar","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, \u0130stanbul Technical University, \u0130stanbul, Turkey"}]},{"given":"Basar","family":"Oztaysi","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, \u0130stanbul Technical University, \u0130stanbul, Turkey"}]}],"member":"179","reference":[{"issue":"1","key":"10.3233\/JIFS-189114_ref1","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/S0165-0114(86)80034-3","article-title":"Intuitionistic fuzzy sets","volume":"20","author":"Atanassov","year":"1986","journal-title":"Fuzzy sets and Systems"},{"issue":"1-2","key":"10.3233\/JIFS-189114_ref4","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/S1071-5819(03)00018-1","article-title":"Emotion and sociable humanoid robots","volume":"59","author":"Breazeal","year":"2003","journal-title":"International Journal of Human-Computer Studies"},{"issue":"3","key":"10.3233\/JIFS-189114_ref5","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1007\/s12369-009-0016-4","article-title":"Gender representation and humanoid robots designed for domestic use","volume":"1","author":"Carpenter","year":"2009","journal-title":"International Journal of Social Robotics"},{"key":"10.3233\/JIFS-189114_ref6","doi-asserted-by":"crossref","first-page":"719","DOI":"10.1016\/j.compeleceng.2015.12.010","article-title":"Kinect microphone array-based speech and speaker recognition for the exhibition control of humanoid robots","volume":"62","author":"Ding","year":"2017","journal-title":"Computers & Electrical Engineering"},{"key":"10.3233\/JIFS-189114_ref7","doi-asserted-by":"crossref","first-page":"2","DOI":"10.3389\/fnbot.2019.00002","article-title":"An improved fuzzy brain emotional learning model network controller for humanoid robots","volume":"13","author":"Fang","year":"2019","journal-title":"Frontiers in Neurorobotics"},{"issue":"1","key":"10.3233\/JIFS-189114_ref8","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1109\/TFUZZ.2006.889755","article-title":"Uncertain fuzzy reasoning: A case study in modelling expert decision making","volume":"15","author":"Garibaldi","year":"2007","journal-title":"IEEE Transactions on Fuzzy Systems"},{"key":"10.3233\/JIFS-189114_ref9","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1002\/malq.19760220120","article-title":"Fuzzy membership mapped onto intervals and many-valued quantities","volume":"22","author":"Grattan-Guinness","year":"1976","journal-title":"Zeitsehr Math Logik und Grundlagen Math"},{"key":"10.3233\/JIFS-189114_ref10","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.robot.2019.02.003","article-title":"Control framework for cooperative object transportation by two humanoid robots","volume":"115","author":"Hawley","year":"2019","journal-title":"Robotics and Autonomous Systems"},{"key":"10.3233\/JIFS-189114_ref11","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1002\/mana.19750680109","article-title":"Intervall-wertige Mengen","volume":"68","author":"Jahn","year":"1975","journal-title":"Math Nach"},{"key":"10.3233\/JIFS-189114_ref12","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.engappai.2017.09.009","article-title":"Onar and B. 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