Roghayeh Hajizadeh

Lecturer

My research area is the application of discrete optimization in solving complex real-life problems. In my work, I explore how discrete optimization techniques can be applied to snow removal problem and air traffic management. This includes formulating the problem as a mathematical model and selecting solution methods or developing methods in order to find good solutions.

I am a part of Mathematics and algorithms for intelligent decision-making research group, and I am currently involved in two research projects. I have been working on Optimization of snow removal in cities since 2017 when I started my PhD studies at LiU. In addition, I have been a part of research project Optimization methods for large air traffic management problems (OPT@ATM) since August 2023.

Research

Mathematics and algorithms for intelligent decision-making

On the journey towards sustainability, our contribution is to develop mathematical models and solution methods for practically relevant but computationally challenging problems in scheduling and resource allocation.

Snow removal with a tractor in Stockholm.

Optimization of Snow Removal in Cities

Snow removal in a city is a major undertaking that requires route planning and efficient driving schedules. It is a difficult and complex optimization problem and research is needed to be able to get good solutions.

OPT@ATM

Some of the planning tasks involved in air traffic management can be considered as optimisation problems. These are typically large scale and difficult to solve.

Teaching

Current teaching

Combinatorial Optimization (TAOP33) for Master of Science in Engineering programmes in Computer Science and Engineering, and Computer Science and Software Engineering.
Supply Chain Optimization (TAOP18) for Master of Science in Engineering programmes in Design and Product Development, Industrial Engineering and Management, Mechanical Engineering, and for Bachelor of Science and Master of Science in Mathematics.

Student theses

List of student theses in DIVA

Publications

2024

Roghayeh Hajizadeh, Tatiana Polishchuk, Elina Rönnberg, Christiane Schmidt (2024) A Dantzig-Wolfe Reformulation for AutomatedAircraft Arrival Scheduling in TMAs Proceedings of the 14th International Conference on the Practice and Theory of Automated Timetabling, PATAT 2024, p. 268-271 (Conference paper)

2023

Roghayeh Hajizadeh (2023) Optimization of Snow Removal in Cities

Roghayeh Hajizadeh, Kaj Holmberg (2023) Lagrangian relaxation for the urban snow removal problem

Roghayeh Hajizadeh, Kaj Holmberg (2023) In search of good relaxations for the urban snow removal problem

2022

Roghayeh Hajizadeh, Kaj Holmberg (2022) Urban snow removal: Tree elimination

Organisation

Illustrative picture representing mathematics

Applied Mathematics (TIMA)

Applied mathematics is used to study advanced methods for modeling in technology as well as natural and social sciences. The division conducts research in computational mathematics, mathematical statistics and optimization.

Department of Mathematics (MAI)

The department conducts research in computational mathematics, mathematics and applied mathematics, mathematical statistics, and optimization. We provide courses to students in most degree programmes in mathematics, science and engineering.

Studenthuset on Campus Valla in Linköping

About LiU

Linköping University, LiU, offers innovative education and boundary-crossing research. The students are among the most desirable in the labour market and international rankings consistently place LiU as a leading global university.

News

Optimizing of snow removal in cities

Researchers at the Mathematics Department of Linköping University have developed a mathematical model on how snow removal can be optimized in Swedish cities.