Classroom Emotional State Analysis Using Proxy Metrics and Multimodal Data. - Tole Bi Yermek; Banu Zh. Yergesh; Amanzhol Yelemessov; Madina Yelemessova; Gulmira Bekmanova; Assel Omarbekova; Aizhan Nazyrova; Zhanar Lamasheva (IEEE Access, 2026)