Per Christian Hansen

2024

CUQIpy: I. Computational uncertainty quantification for inverse problems in Python

Riis, N. A. B., Alghamdi, A. M. A., Uribe, F., Christensen, S. L., Afkham, B. M., Hansen, P. C. & Jørgensen, J. S., 2024, In: Inverse Problems. 40, 4, 37 p., 045009 .

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CUQIpy: II. Computational uncertainty quantification for PDE-based inverse problems in Python

Alghamdi, A. M. A., Riis, N. A. B., Afkham, B. M., Uribe, F., Christensen, S. L., Christian Hansen, P. & Jørgensen, J. S., 2024, In: Inverse Problems. 40, 4, 38 p., 045010 .

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Orbit tomography in constants-of-motion phase-space

Rud, M., Moseev, D., Jaulmes, F., Bogar, K., Dong, Y., Hansen, P. C., Eriksson, J., Järleblad, H., Nocente, M., Prechel, G., Reman, B. C. G., Schmidt, B., Snicker, A., Stagner, L., Valentini, A. & Salewski, M., 2024, In: Nuclear Fusion. 64, 7, 20 p., 076018.

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2023

4D and 5D phase-space tomography using slowing-down physics regularization

Schmidt, B. S., Salewski, M., Moseev, D., Baquero-Ruiz, M., Hansen, P. C., Eriksson, J., Ford, O., Gorini, G., Järleblad, H., Kazakov, Y. O., Kulla, D., Lazerson, S., Mencke, J. E., Mykytchuk, D., Nocente, M., Poloskei, P., Rud, M., Snicker, A., Stagner, L. & Äkäslompolo, S., 2023, In: Nuclear Fusion. 63, 7, 13 p., 076016.

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57 Downloads (Pure)

Horseshoe Priors for Edge-Preserving Linear Bayesian Inversion

Uribe, F., Dong, Y. & Hansen, P. C., 2023, In: SIAM Journal on Scientific Computing. 45, 3, p. B337-B365

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4 Downloads (Pure)

Uncertainty Quantification of Inclusion Boundaries in the Context of X-Ray Tomography

Afkham, B. M., Dong, Y. & Hansen, P. C., 2023, In: SIAM-ASA Journal on Uncertainty Quantification. 11, 1, p. 31-61

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28 Downloads (Pure)

2022

A Hybrid Gibbs Sampler for Edge-Preserving Tomographic Reconstruction with Uncertain View Angles

Uribe, F., Bardsley, J. M., Dong, Y., Hansen, P. C. & Riis, N. A. B., 2022, In: SIAM-ASA Journal on Uncertainty Quantification. 10, 3, p. 1293-1320

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34 Downloads (Pure)

GMRES methods for tomographic reconstruction with an unmatched back projector

Hansen, P. C., Hayami, K. & Morikuni, K., 15 Oct 2022, In: Journal of Computational and Applied Mathematics. 413, 20 p., 114352.

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Iterative image reconstruction for CT with unmatched projection matrices using the generalized minimal residual algorithm

Sidky, E. Y., Hansen, P. C., Jørgensen, J. S. & Pan, X., 2022, Proceedings of the 7th International Conference on Image Formation in X-Ray Computed Tomography. SPIE, Vol. 12304. 7 p. 1230406

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Stopping Rules for Algebraic Iterative Reconstruction Methods in Computed Tomography

Hansen, P. C., Jørgensen, J. S. & Rasmussen, P. W., 2022, Proceedings of 21^st International Conference on Computational Science and Its Applications (ICCSA). IEEE, p. 60-70 9732394

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2021

Algebraic Iterative Reconstruction Methods

Hansen, P. C., 2021, Computed Tomography: Algorithms, Insight, and Just Enough Theory. Hansen, P. C., Jørgensen, J. S. & Lionheart, W. R. B. (eds.). Society for Industrial and Applied Mathematics, p. 211-249 (Fundamentals of Algorithms).

Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Education

A twin error gauge for Kaczmarz's iterations∗

van Lith, B. S., Hansen, P. C. & Hochstenbach, M. E., 2021, In: SIAM Journal on Scientific Computing. p. S173-S199

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Computed Tomography: Algorithms, Insight, and Just Enough Theory

Hansen, P. C. (Editor), Jørgensen, J. S. (Editor) & Lionheart, W. R. B. (Editor), 2021, Society for Industrial and Applied Mathematics. 337 p.

Research output: Book/Report › Book › Education

Computed tomography with view angle estimation using uncertainty quantification

Brogaard Riis, N. A., Dong, Y. & Hansen, P. C., Jun 2021, In: Inverse Problems. 37, 6, 21 p., 065007.

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Discretization Models and the System Matrix

Batenburg, K. J., Hansen, P. C. & Jørgensen, J. S., 2021, Computed Tomography: Algorithms, Insight, and Just Enough Theory. Hansen, P. C., Jørgensen, J. S. & Lionheart, W. R. B. (eds.). Society for Industrial and Applied Mathematics, p. 155-181 (Fundamentals of Algorithms).

Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Education

Just Enough Linear Algebra

Hansen, P. C., 2021, Computed Tomography: Algorithms, Insight, and Just Enough Theory. Hansen, P. C., Jørgensen, J. S. & Lionheart, W. R. B. (eds.). Society for Industrial and Applied Mathematics, p. 27-34 (Fundamentals of Algorithms).

Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Education

Looking Ahead

Hansen, P. C., Jørgensen, J. S. & Lionheart, W. R. B., 2021, Computed Tomography: Algorithms, Insight, and Just Enough Theory. Hansen, P. C., Jørgensen, J. S. & Lionheart, W. R. B. (eds.). Society for Industrial and Applied Mathematics, p. 317-318 (Fundamentals of Algorithms).

Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Education

Singular Values and Functions of the Radon Transform

Hansen, P. C. & Lionheart, W. R. B., 2021, Computed Tomography: Algorithms, Insight, and Just Enough Theory. Hansen, P. C., Jørgensen, J. S. & Lionheart, W. R. B. (eds.). Society for Industrial and Applied Mathematics, p. 105-121 (Fundamentals of Algorithms).

Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Education

SVD Analysis of Tomography Problems

Hansen, P. C., 2021, Computed Tomography: Algorithms, Insight, and Just Enough Theory. Hansen, P. C., Jørgensen, J. S. & Lionheart, W. R. B. (eds.). Society for Industrial and Applied Mathematics, p. 183-209 (Fundamentals of Algorithms).

Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Education

2020

Computed Tomography Reconstruction with Uncertain View Angles by Iteratively Updated Model Discrepancy

Riis, N. A. B., Dong, Y. & Hansen, P. C., 1 Jan 2020, In: Journal of Mathematical Imaging and Vision. 11 p.

Research output: Contribution to journal › Journal article › Research › peer-review

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Fast-ion velocity-space tomography using slowing-down regularization in EAST plasmas with co- and counter-current neutral beam injection: Paper

Madsen, B., Huang, J., Salewski, M., Järleblad, H., Hansen, P. C., Stagner, L., Su, J., Chang, J. F., Fu, J., Wang, J. F., Liang, L. Z., Zhong, G. Q., Li, Y. Y., Lyu, B., Liu, H. Q., Zang, Q., Luo, Z. P., Nocente, M., Moseev, D. & Fan, T. S. & 4 others, Zhang, Y. M., Yang, D., Sun, J. Q. & Liao, L. Y., 2020, In: Plasma Physics and Controlled Fusion. 62, 11, 14 p., 115019 .

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MCMC algorithms for computational UQ of nonnegativity constrained linear inverse problems

Bardsley, J. M. & Hansen, P. C., 1 Jan 2020, In: SIAM Journal on Scientific Computing. 42, 2, p. A1269-A1288

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Tomography of the positive-pitch fast-ion velocity distribution in DIII-D plasmas with Alfvén eigenmodes and neoclassical tearing modes

Madsen, B., Salewski, M., Heidbrink, W. W., Stagner, L., Podestà, M., Lin, D., Garcia, A. V., Hansen, P. C. & Huang, J., 2020, In: Nuclear Fusion. 60, 6, 17 p., 066024 .

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103 Downloads (Pure)

2019

Fixing Nonconvergence of Algebraic Iterative Reconstruction with an Unmatched Backprojector

Dong, Y., Hansen, P. C., Hochstenbach, M. E. & Riis, N. A. B., 2019, In: SIAM Journal on Scientific Computing. 41, 3, p. A1822-A1839

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Hybrid enriched bidiagonalization for discrete ill-posed problems

Hansen, P. C., Dong, Y. & Abe, K., 2019, In: Numerical Linear Algebra with Applications. 26, 3, 9 p., e2230.

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Reconstructing the fast-ion velocity distribution in the DIII-D tokamak during Alfvén eigenmode activity

Madsen, B., Salewski, M., Heidbrink, W. W., Stagner, L., Podestá, M., Lin, D., Garcia, A. V., Hansen, P. C. & Huang, J., 2019, Proceedings of 46th EPS Conference on Plasma Physics. Riconda, C., Brezinsek, S., McCarty, K., Burgess, D., Brault, P. & Farina, D. (eds.). European Physical Society, Vol. 43C. 4 p. P1.1026

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2018

Alpha-particle velocity-space diagnostic in ITER

Salewski, M., Nocente, M., Madsen, B., Abramovic, I., Fitzgerald, M., Gorini, G., Hansen, P. C., Heidbrink, W. W., Jacobsen, A. S., Jensen, T., Kiptily, V. G., Klinkby, E. B., Korsholm, S. B., Kurki-Suonio, T., Larsen, A. W., Leipold, F., Moseev, D., Nielsen, S. K., Pinches, S. D. & Rasmussen, J. & 6 others, Rebai, M., Schneider, M., Shevelev, A., Sipilä, S., Stejner, M. & Tardocchi, M., 2018, In: Nuclear Fusion. 58, 9, 16 p., 096019.

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A spectral geometric model for Compton single scatter in PET based on the single scatter simulation approximation: Paper

Kazantsev, I. G., Olsen, U. L., Poulsen, H. F. & Hansen, P. C., 2018, In: Inverse Problems. 34, 2, 15 p., 024002 .

Research output: Contribution to journal › Journal article › Research › peer-review

Computing segmentations directly from x-ray projection data via parametric deformable curves: Paper

Dahl, V. A., Dahl, A. B. & Hansen, P. C., 2018, In: Measurement Science and Technology. 29, 1, 16 p., 014003.

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824 Downloads (Pure)

Deformable Curves for Outlining Objects Directly From Projections

Dahl, V. A., Koo, J., Hansen, P. C. & Dahl, A. B., 2018. 1 p.

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IR Tools - a MATLAB package of iterative regularization methods and large-scale test problems

Gazzola, S., Hansen, P. C. & Nagy, J. G., 2018, In: Numerical Algorithms. 39 p.

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870 Downloads (Pure)

Joint CT Reconstruction and Segmentation with Discriminative Dictionary Learning

Dong, Y., Hansen, P. C. & Kjer, H. M., 2018, In: Ieee Transactions on Computational Imaging. 4, 4, p. 528 - 536

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Limited-data x-ray CT for underwater pipeline inspection

Riis, N. A. B., Frøsig, J., Dong, Y. & Hansen, P. C., 23 Jan 2018, In: Inverse Problems. 34, 3, 17 p., 034002.

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Unmatched Projector/Backprojector Pairs: Perturbation and Convergence Analysis

Elfving, T. & Hansen, P. C., 2018, In: S I A M Journal on Scientific Computing. 40, 1, p. A573-A591

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2017

AIR Tools II: algebraic iterative reconstruction methods, improved implementation

Hansen, P. C. & Jørgensen, J. S., 2017, In: Numerical Algorithms. p. 1-31 31 p.

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LBAS: Lanczos Bidiagonalization with Subspace Augmentation for Discrete Inverse Problems

Hansen, P. C. & Abe, K., 2017, DTU Compute. 12 p. (DTU Compute Technical Report-2017, Vol. 3).

Research output: Book/Report › Report › Research

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Tomographic image reconstruction using training images

Soltani, S., Andersen, M. S. & Hansen, P. C., 2017, In: Journal of Computational and Applied Mathematics. 313, p. 243-258

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User-friendly simultaneous tomographic reconstruction and segmentation with class priors

Kjer, H. M., Dong, Y. & Hansen, P. C., 2017, Proceedings of 6th International Conference on Scale Space and Variational Methods in Computer Vision. Springer, Vol. 10302. p. 260-270 (Lecture Notes in Computer Science, Vol. 10302).

Research output: Chapter in Book/Report/Conference proceeding › Article in proceedings › Research › peer-review

2016

A Spectral Geometrical Model for Compton Scatter Tomography Based on the SSS Approximation

Kazantsev, I. G., Olsen, U. L., Poulsen, H. F. & Hansen, P. C., 2016, Proceedings of the The 4th International Conference on Image Formation in X-Ray Computed Tomography. p. 577-580

Research output: Chapter in Book/Report/Conference proceeding › Article in proceedings › Research › peer-review

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A tensor-based dictionary learning approach to tomographic image reconstruction

Soltani, S., Kilmer, M. E. & Hansen, P. C., 2016, In: BIT Numerical Mathematics. 56, 4, p. 1425–1454 30 p.

Research output: Contribution to journal › Journal article › Research › peer-review

Convergence analysis for column-action methods in image reconstruction

Elfving, T., Hansen, P. C. & Nikazad, T., 2016, In: Numerical Algorithms. 74, 3, p. 905–924

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High-definition velocity-space tomography of fast-ion dynamics

Salewski, M., Geiger, B., Jacobsen, A. S., Hansen, P. C., Heidbrink, W. W., Korsholm, S. B., Leipold, F., Madsen, J., Moseev, D., Nielsen, S. K., Nocente, M., Odstrčil, T., Rasmussen, J., Stagner, L., Pedersen, M. S. & Weiland, M., 2016, In: Nuclear Fusion. 56, 10, 15 p., 106024.

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Noise robustness of a combined phase retrieval and reconstruction method for phase-contrast tomography

Kongskov, R. D., Jørgensen, J. S., Poulsen, H. F. & Hansen, P. C., 2016, In: Journal of the Optical Society of America A. 33, 4, p. 447-454

Research output: Contribution to journal › Journal article › Research › peer-review

2015

Analysis of Electrically Large Antennas using Fast Physical Optics

Borries, O. P., Viskum, H.-H., Meincke, P., Jørgensen, E., Hansen, P. C. & Schmidt, C. H., 2015, Proceedings of the 9th European Conference on Antennas and Propagation (EuCAP 2015). IEEE, p. 1-5

Research output: Chapter in Book/Report/Conference proceeding › Article in proceedings › Research › peer-review

A Parameter Choice Method for Simultaneous Reconstruction and Segmentation

Romanov, M., Hansen, P. C. & Dahl, A. B., 2015, Kgs. Lyngby: Technical University of Denmark. 14 p. (DTU Compute Technical Report-2015; No. 5).

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Empirical average-case relation between undersampling and sparsity in X-ray CT

Jørgensen, J. S., Sidky, E. Y., Hansen, P. C. & Pan, X., 2015, In: Inverse Problems and Imaging. 9, 2, p. 431-446

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Relaxed Simultaneous Tomographic Reconstruction and Segmentation with Class Priors for Poisson Noise

Romanov, M., Dahl, A. B., Dong, Y. & Hansen, P. C., 2015, Kgs. Lyngby: Technical University of Denmark. 19 p. (DTU Compute Technical Report-2015; No. 6).

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Simultaneous tomographic reconstruction and segmentation with class priors

Romanov, M., Dahl, A. B., Dong, Y. & Hansen, P. C., 2015, In: Inverse Problems in Science and Engineering. 24, 8, p. 1432-1453

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579 Downloads (Pure)

2014

A computationally efficient tool for assessing the depth resolution in large-scale potential-field inversion

Paoletti, V., Hansen, P. C., Hansen, M. F. & Fedi, M., 2014, In: Geophysics. 79, 4, p. A33-A38

Research output: Contribution to journal › Journal article › Research › peer-review

A Computationally Efficient Tool for Assessing the Depth Resolution in Potential-Field Inversion

Paoletti, V., Hansen, P. C., Hansen, M. F. & Fedi, M., 2014, Kgs. Lyngby: Technical University of Denmark. 25 p. (DTU Compute Technical Report-2014; No. 03).

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Per Christian Hansen

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