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Sigurður Freyr Hafstein - Professor
–
School of Engineering and Natural Sciences
Sigurður Freyr Hafstein
Íslenska
Professor
Location
Tæknigarður / Tg-328
Phone
5254661
Email
shafstein [at] hi.is
Unit
Faculty of Physical Sciences
Website
https://notendur.hi.is/~shafstein
ORCID site
https://orcid.org/0000-0003-0073-2765
Research portal – Sigurður Freyr Hafstein
Under construction throughout the autumn semester 2023
Courses 2023 - 2024
STÆ202G - Sets and Metric Spaces
STÆ119F - PDEs and reproducing kernel Hilbert spaces
Published works
2019
Complete Lyapunov Functions: Computation and Applications
Advances in Intelligent Systems and Computing
Fast Algorithms for Computing Continuous Piecewise Affine Lyapunov Functions
Advances in Intelligent Systems and Computing
2018
Construction of a Complete Lyapunov Function using Quadratic Programming
Proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics
Verification of a Numerical Solution to a Collocation Problem
Proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics
Local Lyapunov Functions for Nonlinear Stochastic Differential Equations by Linearization
Proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics
Computational approach for complete Lyapunov functions
Springer Proceedings in Mathematics and Statistics
Probabilistic basin of attraction and its estimation using two lyapunov functions
Complexity
Efficient computation of Lyapunov functions for nonlinear systems by integrating numerical solutions
Nonlinear Dynamics
Lyapunov function computation for autonomous linear stochastic differential equations using sum-of-squares programming
Discrete and Continuous Dynamical Systems - Series B
Iterative Construction of Complete Lyapunov Functions
Proceedings of 8th International Conference on Simulation and Modeling Methodologies, Technologies and Applications
Lyapunov functions for almost sure exponential stability
Springer Proceedings in Mathematics and Statistics
2017
Efficient algorithms for simplicial complexes used in the computation of lyapunov functions for nonlinear systems
SIMULTECH 2017 - Proceedings of the 7th International Conference on Simulation and Modeling Methodologies, Technologies and Applications
Wendland functions A C++ code to compute them
SIMULTECH 2017 - Proceedings of the 7th International Conference on Simulation and Modeling Methodologies, Technologies and Applications
Computation of Lyapunov functions for nonautonomous systems on finite time-intervals by linear programming
Journal of Mathematical Analysis and Applications
Analysing dynamical systems towards computing complete lyapunov functions
SIMULTECH 2017 - Proceedings of the 7th International Conference on Simulation and Modeling Methodologies, Technologies and Applications
The Icelandic Mathematical Society
EMS Newsletter
Efficient Lyapunov Function computation for systems with multiple exponentially stable equilibria
Procedia Computer Science
2015
Huge computational methods for Lyapunov functions
Discrete and Continuous Dynamical Systems - Series B
Computation of Lyapunov functions for systems with multiple local attractors
Discrete and Continuous Dynamical Systems- Series A
Computation of continuous and piecewise affine Lyapunov functions for discrete-time systems
Journal of Difference Equations and Applications
Lyapunov Function Verification: MATLAB Implementation
IFAC-PapersOnLine
Computation of local ISS Lyapunov functions with low gains via linear programming
Discrete and Continuous Dynamical Systems - Series B
Class library in C++ to compute Lyapunov functions for nonlinear systems
IFAC-PapersOnLine
Review on computational methods for Lyapunov functions
Discrete and Continuous Dynamical Systems - Series B
Computing continuous and piecewise affine Lyapunov functions for nonlinear systems
Journal of Computational Dynamics
Computation and verification of lyapunov functions
SIAM Journal on Applied Dynamical Systems
2014
Revised CPA method to compute Lyapunov functions for nonlinear systems
Journal of Mathematical Analysis and Applications
Implementation of a fan-like triangulation for the CPA method to compute Lyapunov functions
Proceedings of the American Control Conference
Computation of Lyapunov functions for discrete-time systems using the Yoshizawa construction
Proceedings of the IEEE Conference on Decision and Control
Computation of Lyapunov functions for nonlinear discrete time systems by linear programming
Journal of Difference Equations and Applications
Computation of continuous and piecewise affine Lyapunov functions by numerical approximations of the Massera construction
Proceedings of the IEEE Conference on Decision and Control
Continuous and piecewise affine Lyapunov functions using the Yoshizawa construction
Proceedings of the American Control Conference
Computation of Lyapunov functions for discrete-time systems using the Yoshizawa construction
53rd IEEE Conference on Decision and Control
Implementation of a fan-like triangulation for the CPA method to compute Lyapunov functions
2014 American Control Conference
Continuous and piecewise affine Lyapunov functions using the Yoshizawa construction
2014 American Control Conference
2013
Implementation of simplicial complexes for CPA functions in C++11 using the armadillo linear algebra library
SIMULTECH 2013 - Proceedings of the 3rd International Conference on Simulation and Modeling Methodologies, Technologies and Applications
Local Lyapunov Functions for Periodic and Finite-Time ODEs
Recent Trends in Dynamical Systems
Local Lyapunov Functions for Periodic and Finite-Time ODEs
Springer Proceedings in Mathematics and Statistics
Construction of a CPA contraction metric for periodic orbits using semidefinite optimization
Nonlinear Analysis, Theory, Methods and Applications
2012
Existence of piecewise linear lyapunov functions in arbitrary dimensions
Discrete and Continuous Dynamical Systems
Linear programming based Lyapunov function computation for differential inclusions
Discrete and Continuous Dynamical Systems - Series B
Construction of Lyapunov functions for nonlinear planar systems by linear programming
Journal of Mathematical Analysis and Applications
2011
Efficient sampling of saddle points with the minimum-mode following method
SIAM Journal on Scientific Computing
2010
Existence of piecewise affine Lyapunov functions in two dimensions
Journal of Mathematical Analysis and Applications
Computing Lyapunov functions for strongly asymptotically stable differential inclusions
IFAC Proceedings Volumes (IFAC-PapersOnline)
2006
OLSIM: Inter-urban traffic information
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
2005
Simulation of the autobahn traffic in north rhine-westphalia
Operations Research/ Computer Science Interfaces Series
Modelling of entries and lane-blocks for up-to-date traffic information systems
Proceedings of the IASTED International Conference on Modelling, Simulation, and Optimization
A constructive converse Lyapunov theorem on asymptotic stability for nonlinear autonomous ordinary differential equations
Dynamical Systems
2004
OLSIM: UP-to-date traffic information on the Web
Proceedings of the Third IASTED International Conference on Communications, Internet, and Information Technology
Traffic forecast in large scale freeway networks
International Journal of Bifurcation and Chaos in Applied Sciences and Engineering
A constructive converse Lyapunov theorem on exponential stability
Discrete and Continuous Dynamical Systems
A high-resolution cellular automata traffic simulation model with application in a freeway traffic information system
Computer-Aided Civil and Infrastructure Engineering
OLSIM: Future traffic information
Proceedings of the IASTED International Conference on Applied Simulation and Modelling
Keywords for Specialisation:
Dynamical systems
Differential equations
Stability in dynamical systems
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