## News

The Systems Theory Research Group is recruiting a new PhD student, starting January 2017 (or as mutually agreed). If you are interested, you may submit the application online at http://www.tut.fi/openpositions (the call is with the title “Doctoral Student/PhD position (Systems Theory Research) – Mathematics”)

The deadline for the applications is on October 2nd, 2017. If you have any questions, please don’t hesitate to contact Assistant Professor Lassi Paunonen for more information (contact details below).

## Research Group

**Group leader:**

**Lassi Paunonen**

Assistant Professor

Academy of Finland Postdoctoral Research Fellow (2016-2019)

(homepage, ResearchGate page, arXiv.org, email: first.last[a]tut.fi)

**Group members:**

**Petteri Laakkonen**, Postdoctoral Research Fellow (email: first.last[a]tut.fi)

**Duy Phan-Duc**, Postdoctoral Research Fellow (email: first.last[a]tut.fi)

**Jukka-Pekka Humaloja**, Doctoral Student (email: first.last[a]tut.fi)

**Seppo Pohjolainen**, Professor Emeritus (email: first.last[a]tut.fi)

### Main Research Interests

The main research interest of the group are the robust control of linear partial differential equations and infinite-dimensional systems, and the practical engineering applications of the theory. You can find an introduction in a poster form here!

Mathematical systems theory studies the behaviour and properties of dynamical models that are described by ordinary and partial differential equations, as well as other models with dynamical behaviour. Such *dynamical systems* arise from modelling phenomena that are encountered in engineering applications and in the nature.

Mathematical control theory concentrates on influencing the behaviour of such dynamical models to either improve the properties of the system or to drive the system into a desirable trajectory.

Mathematical systems theory is used in, for example,

- Trajectory control for unmanned vehicles, such as quadrocopters
- Automatic control of driverless cars
- Rejection of disturbances in industrial processes and acoustics
- Removal of unwanted vibrations in buildings and in machinery

The main research area of the Systems Theory Research Group at TUT is the control of models involving *partial differential equations* and *infinite-dimensional systems*.

This class of models facilitates the control of processes involving, in particular,

- Heat diffusion and material flows
- Vibrations and wave phenomena
- Elastic deformations and bending

Key points of interest of the research group:

- Theory of distributed parameter systems
- Robust output regulation and the Internal Model Principle
- Tracking and rejection of nonsmooth periodic signals
- Semigroup theory and asymptotic behaviour of linear partial differential equations

### Publication Information

List of journal articles

List of conference articles

List of theses

### History

The Systems Theory Research Group at TUT was formed in early 1980’s by Professor Emeritus Seppo Pohjolainen. Since 2016 it has been led by Assistant Professor Lassi Paunonen.

List of completed PhD theses (theses available here):

- Petteri Laakkonen, 2013
- Lassi Paunonen, 2011
- Eero Immonen, 2006
- Timo Hämäläinen, 2005

### Links

Publications of Lassi Paunonen at arXiv.org

Publications of Petteri Laakkonen at arXiv.org

Publications of Jukka-Pekka Humaloja at arXiv.org

Control Theory – Wikipedia

PID Controllers – Wikipedia