Ragnar Winther

    Position : Professor, Director
    Affiliation: Centre of Mathematics for Applications (CMA), University of Oslo.
    Address : CMA c/o Dept of Mathematics, P.O. Box 1053 Blindern, NO-0316 Oslo, NORWAY.
    Office : Room 1009 in Mathematics building (NHA hus)
    Phone : (+47) 22 85 59 35
    Email : ragnar.winther@cma.uio.no

Presentation

Editorial boards

Publications:

  • R.S. Falk and R. Winther Local bounded cochain projections To appear in Math. computation.

  • D.N. Arnold, G. Awanou and R. Winther Nonconforming tetrahedral mixed finite elements for elasticity To appear in Math. models & methods in applied sciences.

  • K.-A. Mardal, J. Schöberl and R. Winther A uniformly stable Fortin operator for the Taylor-Hood element Numer. math. 123 (2013), 537-551.

  • K.-A. Mardal, J. Schöberl and R. Winther A uniform inf-sup condition with applications to preconditioning arXiv:1201.1513v1,2012.

  • S. H. Christiansen and R. Winther On variational eigenvalue approximation of semidefinite operators IMA Journal of Numerical analysis 33 (2013), 164-189.

  • D.N. Arnold, R.S. Falk and R. Winther Finite element exterior calculus: From Hodge theory to numerical stability Bulletin of the Amer. Math. Soc. 47 (2010), 281-354.

  • K.-A. Mardal and R. Winther Preconditioning discretizations of systems of partial differential equatiomns Numerical linear algebra with applications 18 (2011), 1-40.

  • M.E. Rognes and R. Winther Mixed finite element for linear viscoelasticity using weak symmetry Math. models & methods in applied sciences 20 (2010), 955-985.

  • D.N. Arnold, R.S. Falk and R. Winther Geometric decompositions and local bases for spaces of finite element differential forms Computer methods in appl. mech. and eng. 198 (2009), 1660-1672.

  • T. Karper, K.-A. Mardal and R. Winther Unified finite element discretizations of coupled Darcy-Stokes flow Numer. methods for PDEs 25 (2009), 311-326.

  • D.N. Arnold, G. Awanou, and R. Winther Finite elements for symmetric tensors in three dimensions Math. computation 77 (2008), 1229-1251.

  • S. Christiansen and R. Winther Smoothed projections in finite element exterior calculus Math. computation 77 (2008), 813-829.

  • Q. Hu, X.-C Tai, and R. Winther A saddle point approach to the computation of harmonic maps SIAM Jour. Numerical Analysis 47 (2009), 1500-1523.

  • X.-C. Tai and R. Winther A discrete de Rham complex with enhanced smoothness Calcolo 43 (2006), 287-306.

  • D.N. Arnold, R.S. Falk and R. Winther Mixed finite elements for elasticity with weakly imposed symmetry Math. computation 76 (2007), 1699-1723.

  • R. Klausen and R. Winther Robust convergence of multipoint flux approximations on rough grids Numer. math. 104 (2006), 317-337.

  • D.N. Arnold, R.S. Falk and R. Winther Finite element exterior calculus, homological techniques, and applications Acta numerica (2006), 1-155.

  • R. Klausen and R. Winther Convergence of multipoint flux approximations on quadrilateral grids Numer. methods for PDEs 22 (2006), 1438-1454.

  • D.N. Arnold, R.S. Falk and R. Winther Differential complexes and stability of finite element methods. II: The elasticity complex IMA volumes in Math. and appl. 142 (2006), 47-68.

  • D.N. Arnold, R.S. Falk and R. Winther Differential complexes and stability of finite element methods. I: The de Rham complex IMA volumes in Math. and appl. 142 (2006), 23-46.

  • S.H. Christiansen and R. Winther On constraint preservation in numerical simulations of Yang-Mills equations SIAM jour. scientific computing 28 (2006), 75-101.

  • K.-A. Mardal and R. Winther An observation on Korn's inequality for nonconforming finite element methods Math. computations 75 (2006), 1-6.

  • K.-A. Mardal and R. Winther Uniform preconditioners for the time dependent Stokes problem Numer. math. 98 (2004), 305-327. With Erratum

  • I. Ostby and R. Winther Stability of a model of human granulopoiesis using continuous maturation Jour. of math. biology 49 (2004), 501-536.

  • D.N. Arnold and R. Winther Mixed finite elements for elasticity in the stress-displacement formulation Contemporary math. 329 (2003), 33-42.

  • D.N. Arnold and R. Winther Nonconforming mixed elements for elasticity Math. models and methods in appl. sciences 13 (2003), 295-307.

  • K.-A. Mardal, H.P. Langtangen and R. Winther Numerical methods for incompressible viscous flow Advances in water resources 25 (2002), 1125-1146.

  • K.-A. Mardal, X.-C. Tai and R. Winther A robust finite element method for Darcy--Stokes flow SIAM jour. num. anal. 40 (2002), 1605-1631.

  • D.N. Arnold and R. Winther Mixed finite elements for elasticity Numer. math. 92 (2002), 401-419.

  • T. Lyche, T.K. Nilssen and R. Winther Preconditioned iterative methods for scattered data, interpolation Advances in comp. math. 17 (2002), 1605-1631.

  • T. Nilssen, X.-C. Tai and R. Winther A robust nonconforming H2-element Math. computations 70 (2001), 489-505.

  • D.N. Arnold, R.S. Falk and R. Winther Multigrid in H(div) and H(curl) Numer. math. 85 (2000), 197-217.

  • W. Shen, A. Tveto and R. Winther On the zero relaxation limit for a system modeling the motions of a viscoelastic solid SIAM jour. math. anal. 30 (1999), 1115-1135.

  • E. Haug and R. Winther A domain embedding preconditioner for the Lagrange multiplier system Math. computations 69 (1999), 65-82.

  • D.N. Arnold, R.S. Falk and R. Winther Multigrig preconditioning in H(div) on non-convex polygons Comp. appl. math. 17 (1998), 307-319.

  • T. Rusten, P.S. Vassilevski and R. Winther Domain embedding preconditioners for mixed systems Num. linear algebra with appl. 5 (1998), 321-345.

  • E. Haug, T. Rusten, P.S. Vassilevski and R. Winther Domain embedding and the Dirichlet problem Notes on num. fluid dynamics 62 (1998), 66-77.

  • H.J. Schroll, A. Tveito and R. Winther An L1-error bound for a semiimplicit difference scheme applied to a stiff system of consevation laws SIAM jour. math. anal. 34 (1997), 1152-1162.

  • D.N. Arnold, R.S. Falk and R. Winther Preconditioning in H(div) and applications Math. computations 66 (1997), 957-984.

  • D.N. Arnold, R.S. Falk and R. Winther Preconditioning discrete approximations of the Reissner--Mindlin plate model Math. modelling and num. anal. 31 (1997), 517-557.
    August, 2012, RW.