# My academic homepage

Below you will find a short version of my academic curriculum vitae.

My (possibly slightly outdated) full Scientific Resume can be found here.

## Short academic resume

**2016-present:**

Postdoctoral Fellow FWO Flanders, Applied Mathematics Research Group, Dept. of Mathematics and Computer Science, University of Antwerp

Project 12H4617N - Scalable and error resilient iterative solvers for large scale linear algebra problems.

**2015-2016:**

Postdoctoral researcher, Applied Mathematics Research Group, Dept. Mathematics and Computer Science, University of Antwerp.

EXA2CT European project on *EXascale Algorithms and Advanced Computational Techniques*. www.exa2ct.eu.

**2011-2015:**

PhD in Mathematics, Applied Mathematics Research Group, Dept. Mathematics and Computer Science, University of Antwerp.

**2006-2011: **

Graduated (with highest honor) Master in Applied and Financial Mathematics, University of Antwerp.

## Publications and preprints

- [A1]
**[preprint]**S. Cools:

**Analyzing and improving maximal attainable accuracy in thecommunication hiding pipelined BiCGStab method.**

Submitted toElsevier Parallel Computing, PMAA'18 Special Issue, September 2018. - [A1]
**[preprint]**S. Cools:

**Numerical analysis of the maximal attainable accuracy in communication hiding pipelined Conjugate Gradient methods.**

Submitted to SIAM Journal on Scientific Computing (SISC), August 2018. - [A1]
**[preprint]**J. Cornelis, S. Cools, W. Vanroose:

**The communication-hiding Conjugate Gradient method with deep pipelines.**

Submitted to SIAM Journal on Scientific Computing (SISC), January 2018. - [P3]
**[preprint]****[manuscript]**

*Communication Hiding Pipelined Krylov Methods: On Parallel Performance and Numerical Stability of Pipelined Conjugate Gradients.*

Proceedings of the International Conference on Parallel Computing (PARCO 2017),

*Advances in Parallel Computing*, 32, pp. 77-86, IOS Press Amsterdam, Bologna, September 2017. - [A1]
**[preprint]****[manuscript]**

**Analyzing the effect of local rounding error propagation on the maximal attainable accuracy of the pipelined Conjugate Gradient method.**

SIAM Journal on Matrix Analysis and Applicatoins (SIMAX), 39 (1), pp. 426-450, March 2018. - [P3]
**[preprint]****[manuscript]**E. Agullo, S. Cools, L. Giraud, A. Moreau, P. Salas, W. Vanroose, E.F. Yetkin, M. Zounon:

**Hard Faults and Soft-Errors: Possible Numerical Remedies in Linear Algebra Solvers****.**

Conference Proceedings of the 12th International Conference on High Performance Computing in Computational Science (VECPAR 2016),

*High Performance Computing for Computational Science*, 10150, Springer, Cham, pp.11-18, July 2017. - [A1]
**[preprint]****[manuscript]**

*The communication-hiding pipelined BiCGStab method for the parallel solution of large unsymmetric linear systems.*

Parallel Computing, 65, pp. 1-20, Elsevier, July 2017. - [P3]
**[manuscript]**

*On rounding error resilience, maximal attainable accuracy and parallel performance of the pipelined Conjugate Gradients method for large-scale linear systems in PETSc.*

Proceedings of the Exascale Applications and Software Conference, ACM, pp. 20–29, Stockholm, Sweden, April 2016. - [C4]
**[preprint]****[manuscript]**S. Cools, E.F. Yetkin, E. Agullo, L. Giraud, and W. Vanroose:

*Analysis of rounding error accumulation in CG to improve the maximal attainable accuracy of pipelined CG*.

Technical report. University of Antwerp Dept. Mathematics and Computer Science and INRIA Bordeaux, January 2016. - [B2]
**[preprint]****[manuscript]**S. Cools, W. Vanroose:

*On the optimality of shifted Laplacian in the class of expansion preconditioners for the Helmholtz equation.*

Book chapter in "Modern solvers for Helmholtz problems", Lahaye, D., Tang, J., Vuik, K. (Eds.), Springer, February 2017. - [A1]
**[preprint] [manuscript]**S. Cools, W. Vanroose:

*A fast and robust computational method for the ionization cross sections of the driven Schrödinger equation using an O(N) multigrid-based scheme*.

Journal of Computational Physics, 308, pp. 20-39, December 2015. - [A1]
**[preprint]****[manuscript]**S. Cools, P. Ghysels, W. van Aarle, J. Sijbers, W. Vanroose:

*A multi-level preconditioned Krylov method for the efficient solution of algebraic tomographic reconstruction problems.*

Journal of Computational and Applied Mathematics, 283, pp.1-16, August 2015. - [P3]
**[proceedings]**S. Cools, B. Reps, W. Vanroose:

*An efficient multigrid calculation of the Far field map for Helmholtz and Schrödinger equations.*

Proceedings of the 11th International Conference on the Mathematical and Numerical Aspects of Waves, pp. 275-278, Gammarth, Tunisia, June 2013. - [A1]
**[preprint] [manuscript]**S. Cools, B. Reps, W. Vanroose:

*An efficient multigrid calculation of the Far field map for Helmholtz and Schrodinger equations.*

SIAM Journal on Scientific Computing, 36 (3), pp. B367-B395, July 2014. - [A1]
**[preprint] [manuscript]**S. Cools, B. Reps, W. Vanroose:

**A new level-dependent coarsegrid correction scheme for indefinite Helmholtz problems.**

Numerical Linear Algebra with Applications, 21 (4): pp. 513-533, August 2014. - [A1]
**[preprint]****[manuscript]**S. Cools, W. Vanroose:

*Local Fourier Analysis of the Complex Shifted Laplacian preconditioner for Helmholtz problems.*

Numerical Linear Algebra with Applications, 20 (4): pp. 575-597, August 2013. - [C3]
**[contact]**(Manuscript available on demand) S. Cools:

*Multigrid methods for wave scattering problems governed by the Helmholtz and Schrodinger equation.*

PhD dissertation, University of Antwerp, May 22, 2015. - [C3]
**[contact]**(Manuscript available on demand) S. Cools:

*Complex Shifted Multigrid Methods on the indefinite Helmholtz equation.*

Master dissertation, University of Antwerp, in Dutch, June 2011.

## Conference talks and seminars

**PMAA 2018: [slides]**10th International Workshop on Parallel Matrix Algorithms and Applications,

*"Parallel Performance and Numerical Stability of Communication Hiding Pipelined Krylov Subspace Methods",*

Zurich, Switzerland, June 27-29, 2018.**SIAM ALA 2018: [slides]**SIAM Conference on Applied Linear Algebra,

*"Parallel Performance and Numerical Stability of Communication Hiding Pipelined Krylov Subspace Methods",*

Hong Kong, China, May 7-10, 2018.**PARCO 2017: [slides]**International Conference on Parallel Computing,

*"Hiding Global Reduction Latency in Pipelined Krylov Methods: On Parallel Performance and Numerical Stability*

of the Pipelined Conjugate Gradient and BiCGStab Algorithms for Solving Large Scale Linear Systems",

Bologna, Italy, September 12-15, 2017.**GAMM 2017: [slides]**17th GAMM Workshop,

*"Hiding Global Reduction Latency in Pipelined Krylov methods: Parallel Performance and Numerical Accuracy*

of Communication-Hiding Krylov Subspace Methods for Solving Large Scale Linear Systems",

Cologne, Germany, September 7-8, 2017.**LBNL 2017: [slides]**Lawrence Berkeley National Lab

*"Latency hiding of global reductions in pipelined Krylov methods: On Parallel Performance and Numerical Accuracy*

of Communication Hiding Pipelined Krylov Subspace Methods for Solving Large Scale Linear Systems",

Lawrence Berkeley National Laboratory, Berkeley, CA, US, August 7, 2017.**EXA2CT 2016:****[slides]**EXA2CT European FP7 Project Meeting,

*"WP1: Overview of recent solver developments: A general framework for deriving pipelined Krylov methods:*

*application to BiCGStab for large and sparse unsymmetric linear systems"*

Bordeaux, France, September 22-23, 2016.**EASC 2016: [slides]**Exascale Applications and Software Conference

*"Latency hiding of global reductions in pipelined Krylov methods"*

Stockholm, Sweden, April 25-29, 2016.**SIAM PP 2016: [slides]**SIAM Conference on Parallel Processing for Scientific Computing,

*"Latency hiding of global reductions in pipelined Krylov methods"*

Paris, France, April 12-15, 2016.**WAVES 2015:****[slides]**12th International Conference on the Mathematical and Numerical Aspects of Wave Propagation

*"A scalable and robust multigrid-based solver for the far field map of Helmholtz and Schrödinger equations"*

Karlsruhe, Germany, July 20-24, 2015.**PREC 2015:****[slides]**International Conference On Preconditioning Techniques For Scientific And Industrial Applications

*"A robust computational method for the Schrödinger equation cross sections using an MG-Krylov scheme"*

Eindhoven, The Netherlands, June 17-19, 2015.**EMG 2014:****[slides]**European Multigrid Conference 2014

*"A new Level-dependent coarse grid correction scheme for indefinite Helmholtz problems"*

Leuven, Belgium, September 9-12, 2014.**ZSS 2014: [slides]**SAM Zürich Summer School on Advanced Numerical Methods for Non-local Operators

Participant's presentations:*"A Short Research Overview - by Siegfried Cools"*

Zürich, Switzerland, August 18-22, 2014.**WAVES 2013:****[slides]**11th International Conference on the Mathematical and Numerical Aspects of Wave Propagation

*"An Efficient Multigrid Calculation of the Far field map for Helmholtz problems"*

Gammarth, Tunisia, June 3-7, 2013.**CMCMM 2013:****[slides]**16th Copper Mountain Conference on Multigrid Methods

*"An Efficient Multigrid Calculation of the Far field map for Helmholtz problems"*

Copper Mountain, USA, March 17 - 22, 2013.**EMG 2012:****[slides]**European Multigrid Conference 2012

*"Generalised Shifted Multigrid preconditioners for the indefinite Helmholtz equation"*

Schwetzingen, Germany, August 13 - 16, 2012.**ICCAM 2012:****[slides]**International Congress on Computational and Applied Mathematics

*"Generalised Shifted Multigrid preconditioners for the indefinite Helmholtz equation"*

Gent, Belgium, July 9 - 13, 2012.

## General science communication

**PMAA 2018:**10th International Workshop on Parallel Matrix Algorithms and Applications,

*Organizer Minisymposium: "Scalable communication-reducing Krylov subspace methods",*

Zurich, Switzerland, June 27-29, 2018.**SIAM PP 2018:**SIAM Conference on Parallel Processing for Scientific Computing,

*Organizer Minisymposium MS40 (joint with dr. Erin Carson): "Scalable Communication-Avoiding and -Hiding Krylov Subspace Methods",*

Tokyo, Japan, March 4-8, 2018.**PHD 2015:****[slides]**PhD in Science: Mathematics, PhD defense 2015

*"Multigrid methods for wave scattering problems governed by the Helmholtz and Schrodinger equation"*

Antwerpen, Belgium, May 22, 2015.**PROC 2014:****[slides]**

*"Wiskundige algoritmes in het dagelijks leven: de golfvergelijking en haar toepassingen"*(in dutch)

Antwerpen, Belgium, September 18, 2014.**WSC 2011:****[poster]**36th Woudschoten Conference of the Dutch-Flemish Numerical Analysis community: Poster presentation

*"Multigrid rules the Waves: Complex Shifted Multigrid on the indefinite Helmholtz equation"*

Zeist, The Netherlands, October 5 - 7, 2011.

## Teaching

University of Antwerp, Master courses in Financial and Applied Mathematics

**MSc 2018-2019,***Multilevel and Multiscale solution methods*, (lecture + practicum courses)

Course leader(s): Dr. Siegfried Cools**MSc 2017-2018,***Multilevel and Multiscale solution methods*, (lecture + practicum courses)

Course leader(s): Dr. Siegfried Cools

## Assistant Teaching

University of Antwerp, Master courses in Financial and Applied Mathematics

**MSc 2016-2017,***Multilevel and Multiscale solution methods*,

Course leader(s): Prof. Dr. W. Vanroose**MSc 2015-2016,***Multilevel and Multiscale solution methods*,

Course leader(s): Prof. Dr. W. Vanroose**MSc 2014-2015**,*Multilevel and Multiscale solution methods,*

Course leader(s): Prof. Dr. W. Vanroose**MSc 2013-2014**, A*pplications of Partial Differential Equations*,

Course leader(s): Prof. Dr. W. Vanroose, Prof. Dr. K. In't Hout**MSc 2013-2014***, Multilevel and Multiscale solution methods*,

Course leader(s): Prof. Dr. W. Vanroose**MSc 2012-2013***, Multilevel and Multiscale solution methods*,

Course leader(s): Prof. Dr. W. Vanroose**MSc 2011-2012***, Applications of Partial Differential Equations*,

Course leader(s): Prof. Dr. W. Vanroose, Prof. Dr. K. In't Hout

## Awards and grants

**FWO Postdoctoral Fellowship.**Start date: October 2016. End date: September 2019.

Application no. 12H4617N: "*Scalable and error resilient iterative solvers for large scale linear algebra problems"*.

Grant received on June 22, 2016**.**

**Student Paper Award:**16th Copper Mountain Conference on Multigrid Methods (2013),

*"An Efficient Multigrid Calculation of the Far field map for Helmholtz equations"*,

see the Copper Mountain Conference home page for a list of past Student Paper winners.