| [1] | A. A. Chaudhry, C. Zhang, O. G. Ernst, and T. Nagel, “Effects of inhomogeneity
  and statistical and material anisotropy on thm simulations,” 
  Reliability Engineering & System Safety, vol. 260, p. 110921, 2025.
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| [2] | O. Bader, N. E. B. Amara, O. G. Ernst, and O. Kanoun, “Rotating radial
  injection pattern for highly sensitive electrical impedance tomography of
  human lung anomalies,” Physiological Measurement, vol. 13, p. 025001,
  2025.
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| [3] | O. G. Ernst, B. Sprungk, and C. Zhang, “Uncertainty modeling and propagation
  for groundwater flow: A comparative study of surrogates,” International
  Journal on Geomathematics, vol. 15, no. 1, p. Article 11, 2024.
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| [4] | K. Kurgyis, P. Achtziger-Zupančič, M. Bjorge, M. S. Boxberg,
  M. Broggi, J. Buchwald, O. G. Ernst, J. Flügge, A. Ganopolski, T. Graf,
  P. Kortenbruck, J. Kowalski, P. Kreye, P. Kukla, S. Mayr, S. Miro, T. Nagel,
  W. Nowak, S. Oladyshkin, A. Renz, J. Rienäcker-Burschil, K.-J.
  Röhlig, O. Sträter, J. Thiedau, F. Wagner, F. Wellmann, M. Wengler,
  J. Wolf, and W. Rühaak, “Uncertainties and robustness with regard to the
  safety of a repository for high-level radioactive waste: introduction of a
  research initiative,” Environmental Earth Sciences, vol. 83, no. 2,
  p. 82, 2024.
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| [5] | J. Blechta and O. G. Ernst, “Efficient solution of parameter identification
  problems with H1 regularization,” SIAM Journal on Scientific
  Computing, vol. 46, no. 2, pp. A1160-A1185, 2024.
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| [6] | O. G. Ernst, A. Pichler, and B. Sprungk, “Wasserstein sensitivity of risk and
  uncertainty propagation,” SIAM/ASA Journal on Uncertainty
  Quantification, vol. 10, no. 3, pp. 915-948, 2022.
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| [7] | M. Eigel, O. G. Ernst, B. Sprungk, and L. Tamellini, “On the convergence of
  adaptive stochastic collocation for elliptic partial differential equations
  with affine diffusion,” SIAM Journal on Numerical Analysis, vol. 60,
  no. 2, pp. 659-687, 2022.
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| [8] | J. Blechschmidt and O. G. Ernst, “Three ways to solve partial differential
  equations with neural networks: a review,” GAMM Mitteilungen, vol. 44,
  no. 2, p. e202100006, 2021.
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| [9] | D. Gerth, S. Hannusch, O. G. Ernst, and J. Ihlemann, “Regularization for the
  inversion of fibre Bragg grating spectra,” Inverse Problems in
  Science and Engineering, vol. 29, no. 13, pp. 2629-2655, 2021.
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| [10] | O. G. Ernst, B. Sprungk, and L. Tamellini, “Convergence of sparse collocation
  for functions of countably many Gaussian random variables (with application
  to elliptic PDEs),” SIAM Journal on Numerical Analysis, vol. 56,
  no. 2, pp. 877-905, 2018.
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| [11] | O. G. Ernst, B. Sprungk, and H.-J. Starkloff, “Analysis of the ensemble and
  polynomial chaos Kalman filters in Bayesian inverse problems,” 
  SIAM/ASA Journal on Uncertainty Quantification, vol. 3, no. 1, pp. 823-851,
  2015.
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| [12] | R.-U. Börner, O. G. Ernst, and S. Güttel, “Three-dimensional transient
  electromagnetic modelling using rational Krylov methods,” Geophysical
  Journal International, vol. 202, pp. 2025-2043, 2015.
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| [13] | M. Ullmann, U. Prüfert, J. Seidel, O. G. Ernst, and C. Hasse, “Application
  of proper orthogonal decomposition methods in reactive pore diffusion
  simulations,” Canadian Journal of Chemical Engineering, vol. 92,
  no. 9, pp. 1552-1560, 2014.
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| [14] | J. Seidel and O. G. Ernst, “Model reduction for cold rolling processes,” 
  Steel Research, vol. 85, no. 9, pp. 1334-1339, 2014.
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| [15] | H. C. Elman, O. G. Ernst, and E. Ullmann, “Efficient iterative solvers for
  stochastic Galerkin discretizations of log-transformed random diffusion
  problems,” SIAM Journal on Scientific Computing, vol. 34, no. 2,
  pp. A659-A682, 2012.
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| [16] | O. G. Ernst, A. Mugler, H.-J. Starkloff, and E. Ullmann, “On the convergence
  of generalized polynomial chaos expansions,” M2AN, vol. 46, no. 2,
  pp. 317-339, 2012.
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| [17] | I. Busch, O. G. Ernst, and E. Ullmann, “Expansion of random field gradients
  using hierarchical matrices,” PAMM, vol. 11, no. 1, pp. 911-914,
  2011.
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| [18] | M. Eiermann, O. G. Ernst, and S. Güttel, “Deflated restarting for matrix
  functions,” SIAM Journal on Matrix Analysis and Applications, vol. 32,
  no. 2, pp. 621-641, 2011.
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| [19] | O. G. Ernst and E. Ullmann, “Stochastic Galerkin matrices,” SIAM
  Journal on Matrix Analysis and Applications, vol. 31, no. 4, pp. 1848-1872,
  2010.
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| [20] | O. G. Ernst, C. E. Powell, D. Silvester, and E. Ullmann, “Efficient solvers
  for a linear stochastic Galerkin mixed formulation of diffusion problems
  with random data,” SIAM Journal on Scientific Computing, vol. 31,
  no. 2, pp. 1424-1447, 2009.
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| [21] | M. Afanasjew, M. Eiermann, O. G. Ernst, and S. Güttel, “A generalization
  of the steepest descent method for matrix functions,” Electronic
  Transactions on Numerical Analysis, vol. 28, pp. 206-222, 2008.
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| [22] | M. Afanasjew, M. Eiermann, O. G. Ernst, and S. Güttel, “Implementation of
  a restarted Krylov subspace method for the evaluation of matrix
  functions,” Linear Algebra and its Applications, vol. 429, no. 10,
  pp. 2293-2314, 2008.
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| [23] | R.-U. Börner, O. G. Ernst, and K. Spitzer, “Fast 3d simulation of
  transient electromagnetic fields by model reduction in the frequency domain
  using Krylov subspace projection,” Geophysical Journal
  International, vol. 173, pp. 766-780, 2008.
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| [24] | M. Eiermann, O. G. Ernst, and E. Ullmann, “Computational aspects of the
  stochastic finite element method,” Computing and Visualization in
  Science, vol. 10, no. 1, pp. 3-15, 2007.
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| [25] | M. Eiermann and O. G. Ernst, “A restarted Krylov subspace method for the
  evaluation of matrix functions,” SIAM Journal on Numerical Analysis,
  vol. 44, no. 6, pp. 2481-2504, 2006.
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| [26] | H. C. Elman, O. G. Ernst, D. P. O'Leary, and M. Stewart, “Efficient iterative
  algorithms for the stochastic finite element method with applications to
  acoustic scattering,” Computer Methods in Applied Mechanics and
  Engineering, vol. 194, pp. 1037-1055, 2005.
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| [27] | H. C. Elman, O. G. Ernst, and D. P. O'Leary, “A multigrid method enhanced by
  Krylov subspace iteration for discrete Helmholtz equations,” SIAM
  Journal on Scientific Computing, vol. 23, no. 4, pp. 1290-1314, 2001.
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| [28] | M. Eiermann and O. G. Ernst, “Geometric aspects of the theory of Krylov
  subspace methods,” Acta Numerica, vol. 10, pp. 251-312, 2001.
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| [29] | O. G. Ernst, “Equivalent iterative methods for p-cyclic matrices,” 
  Numerical Algorithms, vol. 25, pp. 161-180, 2000.
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| [30] | M. Eiermann, O. G. Ernst, and O. Schneider, “Analysis of acceleration
  strategies for restarted minimal residual methods,” Journal of
  Computational and Applied Mathematics, vol. 123, pp. 262-292, 2000.
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| [31] | O. G. Ernst, “Residual-minimizing Krylov subspace methods for stabilized
  discretizations of convection-diffusion equations,” SIAM Journal on
  Matrix Analysis and Applications, vol. 21, no. 4, pp. 1079-1101, 2000.
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| [32] | O. G. Ernst, “A finite element capacitance matrix method for exterior
  Helmholtz problems,” Numerische Mathematik, vol. 75, no. 2,
  pp. 175-204, 1996.
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| [1] | O. G. Ernst, B. Sprungk, and L. Tamellini, “On expansions and nodes for sparse
  grid collocation of lognormal elliptic PDEs,” in Sparse Grids and
  Applications - Munich 2018 (H.-J. Bungartz, J. Garcke, and D. Pflüger,
  eds.), vol. 144 of LNCSE, pp. 1-31, Cham: Springer International
  Publishing, 2021.
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| [2] | O. G. Ernst, B. Sprungk, and H.-J. Starkloff, “Bayesian inverse problems and
  Kalman filters,” in Extraction of Quantifiable Information from
  Complex Systems (S. e. a. Dahlke, ed.), vol. 102 of Lecture Notes in
  Computational Science and Engineering, pp. 133-159, Springer-Verlag, 2014.
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| [3] | O. G. Ernst and B. Sprungk, “Stochastic collocation for elliptic PDEs with
  random data - the lognormal case,” in Sparse Grids and Applications -
  Munich 2012 (J. Garcke and D. Pflüger, eds.), vol. 97 of Lecture
  Notes in Computational Science and Engineering, pp. 29-53, Springer-Verlag,
  2014.
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| [4] | O. G. Ernst and M. J. Gander, “Multigrid methods for Helmholtz problems: A
  convergent scheme in 1D using standard components,” in Direct and
  Inverse Problems in Wave Propagation and Applications (I. G. Graham,
  U. Langer, J. M. Melenk, and M. Sini, eds.), vol. 14 of Radon Series on
  Computational and Applied Mathematics, Berlin/Boston: Walter de Gruyter
  GmbH, 2013.
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| [5] | O. G. Ernst and M. J. Gander, “Why it is difficult to solve Helmholtz
  problems with classical iterative methods,” in Numerical Analysis of
  Multiscale Problems (I. Graham, T. Hou, O. Lakkis, and R. Scheichl, eds.),
  vol. 83 of Lecture Notes in Computational Science and Engineering,
  (Berlin Heidelberg), pp. 325-361, Springer-Verlag, 2012.
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| [6] | H. C. Elman and O. G. Ernst, “Numerical experiences with a Krylov-enhanced
  multigrid solver for exterior Helmholtz problems,” in Proceedings of
  the Fifth International Conference on Mathematical and Numerical Aspects of
  Wave Propagation, Waves 2000 (Santiago de Compostela) (A. Bermúdez,
  D. Gómez, C. Hazard, P. Joly, and J. E. Roberts, eds.), (Philadelphia),
  SIAM, 2000.
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| [7] | O. G. Ernst and G. H. Golub, A Domain Decomposition Approach to Solving
  the Helmholtz Equation with a Radiation Boundary Condition, vol. 157 of
  Contemporary Mathematics.
 AMS, 1992.
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