We are proud to announce that the paper entitled “A Subspace Framework for H-infinity Norm Minimization” by UFAZ Math Teacher, Nijat Aliyev, PhD, has recently been published in one of the most prestigious and high-rated journals of SIAM. 

It became the first paper from Azerbaijani institutions to have been published in or in any SIAM journal with such a high impact factor.  

Description of Topic and its Development: 

Many physical phenomena in nature and science are described by a term called “dynamical systems.” This term stands for something that evolves in time. These kinds of systems appear widely in nature, physics, biology, chemistry, engineering, economics and many other scientific fields. As an example, we can consider the growth of a population of live beings, such as bacteria, animals, etc. In most of the cases, one desires to “control” the systems. A system that controls another system is called a control system. For example, the control of a car with accelerator and brake pedals. Control of heat by switching the button. Switching on/off the light by a switching button. Human body itself is a control system too. It controls the temperature of the body. When it is too hot, the brain realizes it and sends a signal to regulate the desired temperature. When it needs energy, it feels hungry etc. Roughly speaking, a control system is a set of devices that manages, regulates, directs and commands the behavior (output) of the other devices to get the desired result. H-infinity control is an important method in control theory which is based on a so-called “H-infinity norm” of a given system. 

The paper concerns the minimization of the H-infinity norm of a large-scale control system. Although there are several methods in literature to minimize the H-infinity norm of a control system, none of them are meant for large-scale systems. Therefore, the concerning paper is the first published one in literature so far, regarding the minimization of the H-infinity norm of large-scale control systems. Also, it is the first math paper ever published in a SIAM journal or in a journal with that high rate of impact factor from Azerbaijani institutions.  

We proposed a subspace method to minimize the H-infinity norm of a large-scale control system. Our method is very efficient and fast in practice as well as its efficiency is proved theoretically.  

About the author:  

Nijat Aliyev graduated from the Department of Mathematics of Dokuz Eylül University (Turkey) in 2008. He got his Master’s Degree in Financial Mathematics from Middle East Technical University and Bahçeşehir University in Turkey. In 2018 Nijat Aliyev completed his PhD in applied mathematics at Koç University, Turkey. During his doctoral studies, Nijat joined Max Planck Institute in Magdeburg, Germany as a visiting research fellow. During and after his PhD he lectured math courses at several universities in Turkey, namely Koç University and Sabahattin Zaim University. He worked as an Assistant Professor at Sabahattin Zaim University in 2019. Nijat has published several scientific papers of his research in highly rated and prestigious scientific journals. Currently, he is working as a Research Scientist at Institute of Mathematics and Mechanics in National Academy of Sciences of Azerbaijan, as well as an Adjunct Professor/Lecturer at University of French-Azerbaijani.   

About the journal: 

SIAM Journal on Matrix Analysis and Applications (SIMAX) publishes research papers on matrix and tensor theory, analysis, applications, and computation that are of interest to the applied and numerical linear algebra communities. Applications include such areas as signal processing, systems and control theory, statistics, Markov chains, mathematical biology, graph theory, and data science. SIMAX also publishes papers that are of a theoretical nature but have a potential impact on applications. 

The impact factor of the journal SIMAX, SIAM, Journal of Matrices and Applications, is currently 2.08.  

The UFAZ Team congratulates Mr. Aliyev on his achievements and wishes for many more successes to come!