Colloquium of Applied Mathematics Dr. ir. Wim T van Horssen, On the Perturbation Method and Its Application in the Engineering Sciences

On Thursday, November 10, 2022, the Department of Mathematics, Universitas Gadjah Mada held an applied mathematics colloquium which invited Dr. ir. Wim T van Horssen, a researcher from Delft University of Technology, The Netherlands. The colloquium was held in the Auditorium A1.06-A1.07 of the Faculty of Mathematics and Natural Science, Universitas Gadjah Mada (FMIPA UGM), and also more than 70 participants from domestic and foreign universities joined via zoom meeting.

The opening remark is delivered by Dr. Fajar Adi Kusumo, S.Si., M.Si. as Deputy Dean for Alumni, Cooperation, and Innovation at the Faculty of Mathematics and Natural Science UGM. In his speech, he hoped that this applied mathematics colloquium could be a platform for sharing ideas and also make the participants more interested in the perturbation method and its application to engineering sciences.

Dr. ir. Wim T van Horssen delivered his speech on the perturbation method and its application in engineering sciences. At the beginning of his speech, revealed that a quarter of The Netherlands is below sea level. Similar conditions are also happening in Jakarta where some areas have begun to submerge by seawater.

In this Colloquium, he also talked about his experiences doing research projects on perturbation methods elaborated with his colleagues from various universities in Indonesia, i.e. Universitas, Yogyakarta State University, Bandung Institute of Technology, and several other universities. He explained that mathematical problems may have exact solutions and approximate solutions. In the approximate solution, we need to find out how accurate the approximate solution is. He said “In some cases, approximate solutions can be easily validated by comparing them with exact solutions. Then what if the exact solution is not available, for example for polynomial equations of degree 5 and above?”. There are some theorems to validate errors. However, in practice, because the error is fixed and small, it is difficult to validate its accuracy. This problem had been used as a research topic in collaboration with Fitriana Yuli Saptaningtyas, S.Pd, M.Sc., Dr. Fajar Adi Kusumo, S.Si., M.Si., and Dr.rer. nat. Lina Aryati, MS.

Dr.ir. Wim T van Horssen continued his explanation on how to use the perturbation method in approximating the solution of polynomial equations and differential equations. Their application can be found in engineering: snap-through mechanism; an actuated, nonlinear microbeam; moving boundary or stefan problems; and inclined, damped cable vibrations. These are the results of his research in collaboration with researchers from several universities in Indonesia.

As a closing, Dr. ir. Wim T van Horssen said that there are still many opportunities and possibilities to extend the existing perturbation method and also develop new perturbation method approaches. He closed with the message “Find an interesting field in Mathematics so that you can do interesting research because there are so many interesting problems.”

At the end of the colloquium, The Dean of FMIPA UGM, Prof. Dr. eng. Kuwat Triyana, M.Si, gave a certificate and souvenir to the speaker. The Dean also expressed his great hope to Dr. ir. Wim T van Horssen to continue conducting research in collaboration with researchers at Universitas Gadjah Mada.

Author: Alifenda Irodatu Juniorusis