The Applied Mathematics Research Group, Department of Mathematics, Faculty of Science and Mathematics, Diponegoro University (UNDIP), once again hosted an international academic event in the form of an online Visiting Lecturer Talk. This activity is part of UNDIP’s commitment to strengthening global research networks and enriching the academic community’s understanding of current issues in applied mathematics. On Thursday, October 30, 2025, from 10:00 AM to 12:00 PM (Jakarta Time), the guest lecture titled “Positivity and Stability of Some Hybrid Singular Systems” was successfully held via Zoom Meeting. The event featured Assoc. Prof. Do Duc Thuan from Hanoi University of Science and Technology, Vietnam, a renowned expert in control systems, stability analysis, and singular system theory—particularly in the context of complex hybrid systems. The discussion was moderated by Dr. Sutrisno, a senior lecturer at UNDIP’s Department of Mathematics who is also actively involved in research on dynamic systems and optimal control.
The lecture focused on the characteristics of hybrid singular systems, which combine continuous and discrete dynamics within a mathematically irregular structure. In this context, positivity refers to conditions where system solutions remain within the positive value domain, crucial for real-world applications such as population models, economics, and biomedical engineering. Meanwhile, stability is key to ensuring that the system does not exhibit uncontrolled behavior over time.
Prof. Thuan presented both analytical and numerical approaches to examine the conditions that guarantee system positivity and stability. These included matrix transformation techniques, Lyapunov criteria, and modeling based on differential and algebraic equations. He also showcased several relevant case studies, such as industrial control systems and epidemic models, to demonstrate how these theories can be applied in practical scenarios.
The guest lecture attracted participants from the UNDIP Mathematics Department, including graduate students, lecturers, and researchers with interests in dynamic systems, control theory, and applied mathematics. The session was highly interactive, featuring a Q&A segment that delved deeper into technical aspects and opportunities for future research development. This event not only enhanced participants’ understanding of hybrid system theory but also opened doors for international research collaboration. Through the Applied Mathematics Research Group, UNDIP continues to promote academic activities that are both international and interdisciplinary, as part of its curriculum internationalization strategy and efforts to elevate the quality of higher education.
By featuring a global expert and a topic aligned with contemporary challenges, this Visiting Lecturer Talk stands as a testament to UNDIP’s commitment to building a dynamic, inclusive, and internationally competitive academic ecosystem. The event was funded through the WCU FSM UNDIP 2025 program, supporting the Faculty of Science and Mathematics in its mission to become a globally competitive institution.