Uri Ascher Home Page

Uri M. Ascher

Computer Science, UBC

Office: x451
Phone: 604-827-3997
Fax: 604-822-5485
e-mail: ascher at cs.ubc.ca

Awards

Fellow of the Royal Society of Canada (FRSC), 2018
SIAM Fellow, 2010
CAIMS Research Prize, 2010

Google Scholar

Here is a recent CV

Most Recent Book

Uri Ascher and Chen Greif, A First Course in Numerical Methods , SIAM, 2011.

This is an undergraduate or beginning graduate introductory textbook on numerical methods.
Errata
Supplementary material including matlab programs

Earlier Books

Uri Ascher, 2008, Numerical Methods for Evolutionary Differential Equations
Uri Ascher and Linda Petzold, 1998, Computer Methods for Ordinary Differential Equations and Differential-Algebraic Equations
Uri Ascher, Bob Mattehij and Bob Russell, 1995 (1988), Numerical Solution of Boundary Value Problems for Ordinary Differential Equationsns

Recent publications and preprints

T. Boesen, E. Haber and U. Ascher (2024), J. SISC to appear, arXiv2211.14302:
Neural DAEs: Constrained neural networks

E. Larionov, A. Longva, U. Ascher, J. Bender and D. Pai (2024), TVCG, DOI: 10.1109/TVCG.2024.3437417 :
Implicit frictional dynamics with soft constraints
See also video clip at https://www.cs.ubc.ca/~ascher/papers/friction.mp4

U. Ascher, E. Larionov, H. Sheen, and D. Pai (2021), J. Computational Dynamics, 9(2), 47-68 (2022), DOI: 10.3934/jcd.2021021 :
Simulating deformable objects for computer animation: a numerical perspective

B. Wang, Y. Deng, P. Kry, U. Ascher, H. Huang and B. Chen, Pacific Graphics 39 (7), 81-91 (2020), DOI: 10.1111/cgf.14128 :
Learning elastic constitutive material and damping models
See also video clip at https://www.cs.ubc.ca/~ascher/papers/PG2020.mp4

E. Chen, S. Sheen, U. Ascher and D. Pai, ACM TOG 40 (Issue 1, Article 3), 1-12 (2020), DOI: 10.1145/3410527 :
SIERE: a hybrid semi-implicit exponential integrator for efficiently simulating stiff deformable objects
See also video clip at https://www.cs.ubc.ca/~ascher/papers/csap.m4v

U. Ascher, J. Dynamics and Games 7(2), 123-140 (2020), DOI: 10.3934/jdg.2020008 arXiv1910.02098:
Discrete processes and their continuous limits

E. Chen, D. Levin, D. Kaufman, U. Ascher and D. Pai, Proceedings SCA (2019), ACM, DOI: 10.1145/3309486.3340248 :
EigenFit for Consistent Elastodynamic Simulation Across Mesh Resolution
See also video clip at https://www.youtube.com/watch?v=aIAKBsT96to&feature=youtu.be

U. Ascher and H. Huang, Vietnam J. Math (Aug. 2018), DOI: 10.1007/s10013-018-0299-6:
Numerical analysis in visual computing: what we can learn from each other

B. Wang, P. Kry, Y. Deng, U. Ascher, H. Huang and B. Chen (2019), arXiv1909.01875:
Learning elastic constitutive material and damping models

E. Chen, U. Ascher and D. Pai, IEEE Trans. Computer Graphics, 24(10), 2702-2713 (2018), DOI: 10.1109/TVCG.2017.2768532:
Exponential Rosenbrock-Euler integrators for elastodynamic simulation
See also video clip at https://www.youtube.com/watch?v=oRGuC9GMm8w

V. Albani, U. Ascher, X. Yang and J. Zubelli, Inverse Problems and Imaging 11, 799-823 (2017), DOI: 10.3934/ipi.2017038 :
Data driven recovery of local volatility surfaces

K. Rothauge, E. Haber and U. Ascher, 2016, arXiv1610.02596:
The discrete adjoint method for exponential integration

V. Albani, U. Ascher and J. Zubelli, J. Computational Finance 21(5), 63-95 (2018), DOI: 10.21314/JCF.2017.345 :
Local volatility models in commodity markets and online calibration

K. Rothauge, E. Haber and U. Ascher, 2015, arXiv1509.03801:
Numerical computation of the gradient and the action of the Hessian for time-dependent PDE-constrained optimization problems

B. Wang, L. Wu, K. Yin, U. Ascher, L. Liu and H. Huang, ACM TOG 34(4) (Siggraph) (2015):
Deformation capture and modeling of soft objects

U. Ascher and F. Roosta-Khorasani, Vietnam J. Math. (2016):
Algorithms that satisfy a stopping criterion, probably

F. Roosta-Khorasani, G. Szekely and U. Ascher, SIAM/ASA J. Uncertainty Quantification 3 (2015), DOI: 10.1137/14096311X:
Assessing stochastic algorithms for large scale nonlinear least squares problems using extremal probabilities of linear combinations of gamma variables

H. Huang, K. Yin, M. Gong, D. Lischinski, D. Cohen-Or, U. Ascher and B. Chen, ACM Trans. Graphics 32(5) (SIGGRAPH Asia) (2013):
``Mind the gap'': tele-registration for structure-driven image completion
See also the project home page

F. Roosta-Khorasani, K. van den Doel and U. Ascher, ETNA 42, (2014), 177-196 arXiv1312.0707:
Data completion and stochastic algorithms for PDE inversion problems with many measurements

F. Roosta-Khorasani and U. Ascher, J. Found. of Comp. Math. (2014), DOI: 10.1007/s10208-014-9220-1 arXiv1308.2475:
Improved bounds on sample size for implicit matrix trace estimators

K. van den Doel, U. Ascher and E. Haber, in ``Large Scale Inverse Problems'', M. Cullen, M. Freitag, S. Kindernmann and R. Scheichl (Eds.), de Gryter (2013), 181-203:
The lost honour of l2-based regularization.

F. Roosta-Khorasani, K. van den Doel and U. Ascher, SIAM J. Scient. Comput. 36, s3-s22 (2014), DOI: 10.1137/130922756.
Stochastic algorithms for inverse problems involving PDEs and many measurements

H. Huang, S. Wu, M. Gong, D. Cohen-Or, U. Ascher and R. Zhang, ACM Trans. Graphics 32(1) (2013):
Edge-aware point set resampling

K. van den Doel and U. Ascher, SIAM J. Scient. Comput. (2012), DOI: 10.1137/110826692:
Adaptive and stochastic algorithms for EIT and DC resistivity problems with piecewise constant solutions and many measurements.

K. van den Doel and U. Ascher, J. Scientific Computing (2011), DOI10.1007/s10915-011-9521-3 :
The chaotic nature of faster gradient descent methods

K. van den Doel, U. Ascher and D. Pai, Inverse Problems 27 (2011), 025008:
Source localization in electromyography using the inverse potential problem

U. Ascher, J. Appl. Numer. Math. (2012), DOI: 10.1016/j.apnum.2012.06.025
Surprising computations

H. Huang, D. Li, R. Zhang, U. Ascher and D. Cohen-Or, ACM Trans. Graphics 28(5) (SIGGRAPH Asia) (2009):
Consolidation of unorganized point clouds for surface reconstruction
See also the project home page

K. van den Doel, U. Ascher and A. Leitao, J. Scient. Comput. 43 (2009), 44-66:
Multiple level sets for piecewise constant surface reconstruction in highly ill-posed problems

H. Huang and U. Ascher, Vietnam J. Math. 42 (2014), 115-131 arXiv1308.2464:
Faster gradient descent and the efficient recovery of images

U. Ascher, K. van den Doel, H. Huang and B. F. Svaiter, M2AN 43 (2009), 689-708:
Gradient descent and fast artificial time integration

K. van den Doel, U. Ascher and D. Pai, Inverse Problems 24 (2008), 065010:
Computed myography: three dimensional reconstruction of motor functions from surface EMG data

H. Huang and U. Ascher, SIAM J. Scient. Comput. 31 (2008), 74-93:
Surface mesh smoothing, regularization and feature detection

K. van den Doel and U. Ascher, IEEE Trans. Audio, Speech and Language Processing16 (2008), 1163-1172:
Real-time numerical solution of Webster's equation on a non-uniform grid

H. Huang and U. Ascher, Inverse Problems 24 (2008), 034003:
Fast Denoising of Surface Meshes with Intrinsic Texture

For my other publications click Publications

Other

Subgroup picture: Ray Spiteri, Hui Huang, Eldad Haber, me, John Stockie, Chen Greif, Dhavide Aruliah, David Moulton, Sebastian Reich, Steve Ruuth, Ping Lin

Travel photos

University of British Columbia
Computer Science Department
Scientific Computing Laboratory
Applied Mathematics