The Faculty of Mathematics and Natural Sciences (FMIPA) at Yogyakarta State University (UNY) has once again produced a new doctor in the field of Mathematics Education. The Open Doctoral Promotion Session for Yanuar Hery Murtianto, S.Pd., M.Pd.., was held solemnly in the FMIPA UNY Meeting Room. The event was attended by faculty leaders, the examination team, promoters, guests from PGRI University Semarang (UPGRIS), and the promovendus' extended family.

Yanuar Hery Murtianto, a lecturer at PGRI University Semarang, defended his dissertation titled "Self-efficacy and Mathematics Multimedia Learning Based on Cognitive Load Theory". In his research, Yanuar raised important issues regarding the complexity of mathematical material in higher education, which often causes excessive cognitive load on students and low self-efficacy in advanced mathematics learning. This dissertation offers solutions by developing multimedia learning based on cognitive load theory. Yanuar researched the effectiveness of persuasive prompts and verbal messages in multimedia to reduce cognitive load and increase students' self-confidence. This study used a factorial experimental design involving prospective mathematics teachers at six universities in Central Java, focusing on multivariable calculus material.

One of the interesting findings presented by Yanuar concerned the influence of the voice principle on learning multimedia. He compared the use of public figures' voices (such as B.J. Habibie and Sri Mulyani) with the original voices of lecturers (lecture voice) who were familiar to students. The results showed that familiar lecturer voices had a more significant positive impact on self-efficacy and cognitive load than public figures' voices.

The Chair of the Examination Board, Prof. Dr. Tien Aminatun, M.Si., accompanied by the Secretary of the Examination Board, Prof. Wahyu Setyaningrum, M.Ed., Ph.D. Acting as the Promoter was Endah Retnowati, M.Ed., Ph.D., along with Co-promoters Prof. Dr. Sugiman, M.Si., and Dr. Jose Hanham from Western Sydney University. The material examination team consisted of Prof. Dr. Ariyadi Wijaya, M.Sc., and the external examiner, Prof. Rully Charitas Indra Prahmana, M.Pd. The question-and-answer session was dynamic, with the examiners delving deeper into the research's novelty and implications. Prof. Ariyadi Wijaya highlighted the need to generalize Yanuar's findings to education levels below university. Yanuar explained that the principles of cognitive load and multimedia learning he developed could be adapted for elementary through high school levels, with adjustments to student characteristics and material.

After the examination and discussion with the examination board, Yanuar Hery Murtianto passed with very satisfactory results. He achieved a Grade Point Average (GPA) of 3.98 and was awarded Cum Laude (With Honors). Yanuar completed his studies in exactly 48 months, or 4 years, making him the 12th doctoral graduate from FMIPA UNY. In his speech on behalf of PGRI University Semarang, UPGRIS Vice Rector IV, Prof. Dr. Nur Khoiri, expressed his pride in his teaching staff's academic achievements. He described Yanuar as a resilient academic who completed his doctoral studies on time with an impressive distinction, while remaining active in community service in the field of millennial agriculture. An emotional atmosphere filled the room when Dr. Yanuar delivered his closing speech. With a trembling voice, he expressed his deep gratitude to his parents, wife, and children, who had been his strongest supporters throughout the long, exhausting study process. He dedicated this degree to the fruit of his mother's long prayers and his family's sacrifices.

The event concluded with congratulations and a group photo session. Dr. Yanuar Hery Murtianto's graduation is expected to significantly contribute to the development of mathematics education technology in Indonesia, particularly in the design of effective learning media that support students' cognitive processes. (HnR)