Antti Koskela

Numerical analysis group
Department of Mathematics
KTH Royal Institute of Technology

Email: akoskela at kth dot se

Research interests

Time integrators for ODEs and PDEs and numerical linear algebra. More specifically

• Exponential integrators

• Krylov subspace methods for matrix functions:
  methods for structured matrices (e.g., Hamiltonian, symplectic),
  convergence analysis of the Krylov subspace approximations

• Structure preserving integrators for Hamiltonian ODEs

Preprints

• Analysis of Krylov Subspace Approximation to Large Scale Differential Riccati Equations
  A. Koskela and H. Mena
  preprint (arXiv)
  

• Krylov integrators for Hamiltonian systems
  T. Eirola and A. Koskela
  preprint (arXiv)
  

• On a generalization of the Bessel function Neumann expansion
  A. Koskela and E. Jarlebring
  preprint (arXiv)
  

• The infinite Arnoldi exponential integrator for linear inhomogeneous ODEs
  A. Koskela and E. Jarlebring.
  preprint (arXiv)
  

Journal articles

• Disguised and new quasi-Newton methods for nonlinear eigenvalue problems
  E. Jarlebring, A. Koskela, and G. Mele.
  preprint (arXiv)
  Accepted for publication in Numerical Algorithms.
  

• Krylov approximation of ODEs with polynomial parameterization
  A. Koskela, E. Jarlebring and M.E. Hochstenbach.
  SIAM J. Matrix Anal. Appl. 37(2), 518-538, 2016.
  preprint
  

• Splitting methods for time integration of trajectories in combined electric and magnetic fields.
  C. Knapp, A. Kendl, A. Koskela, A. Ostermann.
  Physical Review E 92, 063310, 2015.
  DOI 10.1103/PhysRevE.92.063310
  preprint
  

• A moment-matching Arnoldi iteration for linear combinations of phi functions.
  A. Koskela, A. Ostermann
  SIAM J. Matrix Anal. & Appl. 35, 1344-1363, 2014.
  DOI 10.1137/130945156
  preprint

• Artificial viscosity in comoving curvilinear coordinates: towards a differential geometrically consistent implicit advection scheme.
  H.Höller, A.Koskela, E.Dorfi, W.Benger
  Computational Astrophysics and Cosmology 1, 1-11, 2014.
  DOI: 10.1186/s40668-014-0002-6
  article

• Ethylene glycol revisited: Molecular dynamics simulations and visualization of the liquid and its hydrogenbond network.
  A. Kaiser, O. Ismailovaa, A.Koskela, S.E. Huber, M. Ritter, B. Cosenza, W. Benger, R. Nazmutdinov, M. Probst
  Journal of Molecular Liquids 189, 20-29, 2013.
  DOI:10.1016/j.molliq.2013.05.033

• Exponential Taylor methods: analysis and implementation.
  A.Koskela, A. Ostermann
  Comput. Math. Appl. 65, 487-499, 2013.
  DOI 10.1016/j.camwa.2012.06.004
  preprint
  

Proceeding articles

• Approximating the matrix exponential of an advection-diffusion operator using the incomplete orthogonalization method.
  A. Koskela
  In: Numerical Mathematics and Advanced Applications-ENUMATH 2013.
  Springer International Publishing, 2015. 345-353.
  DOI 10.1007/978-3-319-10705-9__34
  preprint
  

• Damping optimization in vibrational systems based on amplitude.
  J. Denissen, A. Koskela, H. Mena, Z. Tomljanović
  Damping optimization in vibrational systems based on amplitude.
  In: 21st International Symposium on Mathematical Theory of Networks and Systems (MTNS 2014), 2014. 1222-1227.
  ISBN: 978-90-367-6321-9
  

• Investigation of the recombination of the retarded shell of "born-again" CSPNe by time-dependent radiative transfer models.
  A. Koskela, S. Dalnodar, R. Kissmann, A. Reimer, A. Ostermann, S. Kimeswenger
  In: Planetary Nebulae: An Eye to the Future, IAU Symposium No. 283, 2011
  (A. Manchado, L. Stanghellini, and D. Schönberner, eds.), Proc. Int. Astron. Union, 7, S283, 412-413, 2012.
  DOI 10.1017/S1743921312011684