Fast solvers for frequency domain wave-scattering problems and applications
Lead Research Organisation:
University of Strathclyde
Department Name: Mathematics and Statistics
Abstract
Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.
Organisations
- University of Strathclyde (Lead Research Organisation)
- University of Geneva (Collaboration)
- University of Toulouse (Collaboration)
- Sorbonne University (Collaboration)
- ETH Zurich (Collaboration)
- University of Bath (Collaboration)
- ABB Group (Collaboration)
- UNIVERSITY OF STRATHCLYDE (Collaboration)
- Heidelberg University (Collaboration)
- INRIA Nice (Collaboration)
- University of Côte d'Azur (Collaboration)
- Delft University of Technology (TU Delft) (Collaboration)
People |
ORCID iD |
| Victorita Dolean Maini (Principal Investigator) |
Publications
Alexandros Kyriakis
(2022)
Scalable domain decomposition methods for time-harmonic wave propagation problems
Bonazzoli M
(2019)
Domain decomposition preconditioning for the high-frequency time-harmonic Maxwell equations with absorption
in Mathematics of Computation
Bootland N
(2022)
Can DtN and GenEO Coarse Spaces Be Sufficiently Robust for Heterogeneous Helmholtz Problems?
in Mathematical and Computational Applications
Bootland N
(2021)
Analysis of parallel Schwarz algorithms for time-harmonic problems using block Toeplitz matrices
in ETNA - Electronic Transactions on Numerical Analysis
Bootland N
(2023)
Overlapping Schwarz methods with GenEO coarse spaces for indefinite and nonself-adjoint problems
in IMA Journal of Numerical Analysis
Bootland N
(2021)
A comparison of coarse spaces for Helmholtz problems in the high frequency regime
in Computers & Mathematics with Applications
Brunet R
(2020)
Domain Decomposition Methods in Science and Engineering XXV
Brunet R
(2020)
Natural Domain Decomposition Algorithms for the Solution of Time-Harmonic Elastic Waves
in SIAM Journal on Scientific Computing
Claeys X
(2019)
An introduction to multi-trace formulations and associated domain decomposition solvers
in Applied Numerical Mathematics
Coli V
(2019)
Detection of Simulated Brain Strokes Using Microwave Tomography
in IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology
Operto S
(2023)
Is 3D frequency-domain FWI of full-azimuth/long-offset OBN data feasible? The Gorgon data FWI case study
in The Leading Edge
Tournier P
(2019)
Microwave tomographic imaging of cerebrovascular accidents by using high-performance computing
in Parallel Computing
| Description | 1. (Joint with our partners at University of Bath) We have analysed domain decomposition solvers for Maxwells equations in the high frequency regime and tested the methods on several challenging test problem showing efficiency on thousands of processors. This work was published in a top journal. 2. (Joint with our partners at University of Bath, also University of Heidelberg). At the start of this project, spectral coarse spaces consisting of oscillatory bases had been proposed for accelerating domain decomposition algorithms for high frequency wave propagation, but there was little theoretical understanding. We obtained a rigorous analysis of methods based on spectral coarse spaces for heterogeneous indefinite and non self-adjoint problems, and have produced significant implementations of these in the software system Freefem. This work is continuing in collaboration between Bath and Strathclyde through a PhD project at Strathclyde. 3. In collaboration with Sorbonne University (Paris, France) we have designed, analysed and implemented robust methods for heterogeneous low-frequency Maxwell problems as they arise in applications from electrical engineering. This relies on a preconditioner for positive Maxwell equation and improves the state of the art for more realistic configurations. 4. We have introduced a new fast parallel solver (two-level method) for time-harmonic wave-propagation problems in frequency regime and applied this preconditioner to challenging problems from geophysics. The solution time has been substantially improved for realistic configurations. This is a result of a collaboration with geophysicists (Géoazur, France) and Sorbonne University and lead to publications in top geophysical journals. 5. We have done extensive tests on benchmark problems and enriched the state of the art of solvers in open source software such as Freefem. This is a work in collaboration with Sorbonne university where Freefem software is developed. 6. We have designed novel discretisation methods for Helmholtz that could lead to a substantial improvement in the number of degrees of freedom. This work is continuing in collaboration between Strathclyde and Inria through a PhD project at Inria. 7. (Together with our partners at Bath) we organised an international workshop to disseminate the findings of this project,. This took place at Strathclyde in June 2022 and was supported financially by International Centre for Mathematical Sciences, London Mathematical Society and Glasgow Math Journal Trust. More than 40 invitation-only participants attended and were supported financially, and all but 2 attended in person. The ICMS post-workshop questionnaire indicated huge satisfaction with the workshop from the attendees. |
| Exploitation Route | Academic researchers needing to solve huge systems arising in wave propagation now have substantial mathematical analysis and example software which can be used to guide their choice of solver. The work on solvers for high frequency problems will be used by software developers within the modern systems Freefem and HPDDM. Substantial experimental Helmholtz code has also been created within the system Firedrake and the results communicated to the Firedrake development team. These new high-performance solvers we developed will contribute (among other applications) to the numerical modelling of inverse problems in geophysics and make available these tools to different scientific and engineering communities. These algorithms have also been communicated to other international scientists in through presentations at international conferences. Our work was judged interesting by ABB Switzerland and funding was obtained (EPSRC IAA) for a project to make an impact in an industrial environment. |
| Sectors | Electronics,Energy,Environment |
| URL | https://www.icms.org.uk/workshops/2022/icmsstrathclyde-solvers-frequency-domain-wave-problems-and-applications |
| Description | Conference grant : Fast solvers for frequency-domain wave-scattering problems and applications |
| Amount | £5,292 (GBP) |
| Funding ID | 12113 |
| Organisation | London Mathematical Society |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 06/2022 |
| End | 06/2022 |
| Description | Fast solvers for frequency-domain wave-scattering problems and applications |
| Amount | £24,000 (GBP) |
| Organisation | International Centre for Mathematical Sciences (ICMS) |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 06/2022 |
| End | 06/2022 |
| Description | Glasgow Mathematical Journal Trust Learning and Research Support Fund |
| Amount | £4,000 (GBP) |
| Funding ID | G2001-DOL |
| Organisation | University of Glasgow |
| Department | Glasgow Mathematical Journal Learning and Research Support Fund |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 01/2020 |
| End | 09/2020 |
| Description | Analysis of Schwarz methods using block Toeplitz matrices |
| Organisation | University of Strathclyde |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | With Alex Kyriakis (former PhD student at Strathclyde, now PDRA at the University of Loughborough) and my former PDRA Niall Bootland (now researcher at STFC RAL in Oxford), we worked with Jennifer Pestana from Strathclyde on the analysis of Schwarz methods by using tools from numerical linear algebra (Toeplitz matrices). |
| Collaborator Contribution | Jennifer Pestana is an expert in numerical linear algebra and more precisely in Toeplitz matrices. |
| Impact | A research paper was published in ETNA (Electronic Transactions in Numerical Analysis) journal N Bootland, V Dolean, A Kyriakis, J Pestana: Analysis of parallel Schwarz algorithms for time-harmonic problems using block Toeplitz matrices, ETNA-Electronic Transactions on Numerical Analysis 55, 112-141, 2022. |
| Start Year | 2020 |
| Description | Coarse space for Helmholtz equation |
| Organisation | Sorbonne University |
| Country | France |
| Sector | Academic/University |
| PI Contribution | Together my former PDRA Niall Bootland (now researcher at STFC RAL, Oxford), we worked Pierre Jolivet and Pierre-Henri Tournier on the comparison of coarse space solvers for the Helmholtz equation. We have assessed numerically the main methods from the state of the art and tested them on benchmark problems. A further finer assessment has been performed on simpler test cases to compare the best coarse space methods for Helmholtz. |
| Collaborator Contribution | Pierre Jolivet is a computer scientist at the origin of the hpddm (https://github.com/hpddm/hpddm) standalone library on domain decomposition methods and Pierre-Henri Tournier has developed the ffddm library (https://doc.freefem.org/documentation/ffddm/index.html) inside the open source domain specific language Freefem++. |
| Impact | This is a multidisciplinary collaboration between mathematicians and computer scientists Our work was published in CAMWA (https://www.journals.elsevier.com/computers-and-mathematics-with-applications) N Bootland, V Dolean, P Jolivet, PH Tournier, "A comparison of coarse spaces for Helmholtz problems in the high frequency regime" Computers & Mathematics with Applications 98, 239-253, 2021. The second work was recently published in MDPI- MCA N Bootland, V Dolean, "Can DtN and GenEO coarse spaces be sufficiently robust for heterogeneous Helmholtz problems?", Mathematical and Computational Applications 27 (3), 2022 |
| Start Year | 2020 |
| Description | Coarse space for Helmholtz equation |
| Organisation | University of Toulouse |
| Country | France |
| Sector | Academic/University |
| PI Contribution | Together my former PDRA Niall Bootland (now researcher at STFC RAL, Oxford), we worked Pierre Jolivet and Pierre-Henri Tournier on the comparison of coarse space solvers for the Helmholtz equation. We have assessed numerically the main methods from the state of the art and tested them on benchmark problems. A further finer assessment has been performed on simpler test cases to compare the best coarse space methods for Helmholtz. |
| Collaborator Contribution | Pierre Jolivet is a computer scientist at the origin of the hpddm (https://github.com/hpddm/hpddm) standalone library on domain decomposition methods and Pierre-Henri Tournier has developed the ffddm library (https://doc.freefem.org/documentation/ffddm/index.html) inside the open source domain specific language Freefem++. |
| Impact | This is a multidisciplinary collaboration between mathematicians and computer scientists Our work was published in CAMWA (https://www.journals.elsevier.com/computers-and-mathematics-with-applications) N Bootland, V Dolean, P Jolivet, PH Tournier, "A comparison of coarse spaces for Helmholtz problems in the high frequency regime" Computers & Mathematics with Applications 98, 239-253, 2021. The second work was recently published in MDPI- MCA N Bootland, V Dolean, "Can DtN and GenEO coarse spaces be sufficiently robust for heterogeneous Helmholtz problems?", Mathematical and Computational Applications 27 (3), 2022 |
| Start Year | 2020 |
| Description | Fast solvers for low frequency electromagnetic applications |
| Organisation | ABB Group |
| Department | ABB Corporate Research Centre (Switzerland) |
| Country | Switzerland |
| Sector | Private |
| PI Contribution | At the Stakeholders meeting in Bath 2019, discussions were initiated with Joerg Ostrowski from ABB (Switzerland) who shown an interest in the development of fast solvers for low frequency Maxwell's equations. This motivated the work on preconditioners for positive Maxwell's equations in collaboration with Sorbonne university. On the occasion of the ICMS workshop we rediscussed the possibility to transfer the results we obtained on simple tests cases in and industrial environment. To this end, a proposal was submitted to the University of Strathclyde in October 2022. |
| Collaborator Contribution | V. Dolean was awarded an EPSRC Impact Accelerator Account by the University of Strathclyde and ABB committed to an equivalent in-kind contribution. The formal agreement is still on preparation and the project is due to start as soon as this is finalised. |
| Impact | None as yet. |
| Start Year | 2022 |
| Description | Frequency-domain seismic wave modelling based upon multi-level domain-decomposition preconditioners |
| Organisation | Sorbonne University |
| Country | France |
| Sector | Academic/University |
| PI Contribution | This work was done in collaboration with: - Stéphane Operto, CNRS senior researcher at the Géoazur Laboratory (part of Observatoire de la Côte d'Azur), member of the University Côte d'Azur - Pierre-Henri Tournier, CNRS research engineer at Sorbonne University - Pierre Jolivet, CNRS junior researcher at the University of Toulouse (now in Sorbonne University) on the application of fast solvers to realistic geophysical problems. Two-level preconditionners developed by our team have been applied to difficult benchmark problems in geophysical applications. |
| Collaborator Contribution | Pierre-Henri Tournier and Pierre Jolivet have performed extensive tests on parallel computers to assess the performance of the method Stéphane Operto provided the benchmark problems and brought the expertise on the applications side. |
| Impact | This is a multidisciplinary collaboration: geophysics, computer science and mathematics. A paper was accepted for publication on Geophysics: - PH Tournier, P Jolivet, V Dolean, HS Aghamiry, S Operto, S Riffo, "3D finite-difference and finite-element frequency-domain wave simulation with multilevel optimized additive Schwarz domain-decomposition preconditioner: A tool for full-waveform inversion of sparse node data sets", Geophysics 87 (5), T381-T402. Moreover a case study on a realistic application was recently published in Leading Edge (main communication journal for the geophysical community) - S Operto, P Amestoy, H Aghamiry, S Beller, A Buttari, L Combe, V Dolean, M Gerest, G Guo, P Jolivet, J-Y L'Excellent, F Mamfoumbi, T Mary, C Puglisi, A Ribodetti, P-H Tournier "Is 3D frequency-domain FWI of full-azimuth/long-offset OBN data feasible? The Gorgon data FWI case study" The Leading Edge 42 (3), 173-183, 2023 The outcomes resulting from this collaboration have also been presented at a few major conferences: - The contribution we submitted to the SEG Annual Event (https://seg.org/am/2020) a yearly world event of the geophysical community, has been presented at the virtual conference that took place online in October 2020 V Dolean, PH Tournier, P Jolivet, S Operto, "Large-scale frequency-domain seismic wave modeling on h-adaptive tetrahedral meshes with iterative solver and multi-level domain-decomposition preconditioners", SEG Technical Program Expanded Abstracts 2020, 2683-2688. - The contribution we submitted to the EAGE conference (https://eage.eventsair.com/eageannual2020/), a recurrent reference European event for the geophysical community, has been presented at the virtual conference that took place online in December 2020 V Dolean, P Jolivet, P Tournier, S Operto, Iterative frequency-domain seismic wave solvers based on multi-level domain-decomposition preconditioners, 82nd EAGE Annual Conference & Exhibition 2020 (1), 1-5 - The contribution we submitted to the WCCM-ECCOMAS 2020 conference (https://www.wccm-eccomas2020.org/frontal/) has been presented at the virtual event that took place January 2021. |
| Start Year | 2019 |
| Description | Frequency-domain seismic wave modelling based upon multi-level domain-decomposition preconditioners |
| Organisation | University of Côte d'Azur |
| Country | France |
| Sector | Academic/University |
| PI Contribution | This work was done in collaboration with: - Stéphane Operto, CNRS senior researcher at the Géoazur Laboratory (part of Observatoire de la Côte d'Azur), member of the University Côte d'Azur - Pierre-Henri Tournier, CNRS research engineer at Sorbonne University - Pierre Jolivet, CNRS junior researcher at the University of Toulouse (now in Sorbonne University) on the application of fast solvers to realistic geophysical problems. Two-level preconditionners developed by our team have been applied to difficult benchmark problems in geophysical applications. |
| Collaborator Contribution | Pierre-Henri Tournier and Pierre Jolivet have performed extensive tests on parallel computers to assess the performance of the method Stéphane Operto provided the benchmark problems and brought the expertise on the applications side. |
| Impact | This is a multidisciplinary collaboration: geophysics, computer science and mathematics. A paper was accepted for publication on Geophysics: - PH Tournier, P Jolivet, V Dolean, HS Aghamiry, S Operto, S Riffo, "3D finite-difference and finite-element frequency-domain wave simulation with multilevel optimized additive Schwarz domain-decomposition preconditioner: A tool for full-waveform inversion of sparse node data sets", Geophysics 87 (5), T381-T402. Moreover a case study on a realistic application was recently published in Leading Edge (main communication journal for the geophysical community) - S Operto, P Amestoy, H Aghamiry, S Beller, A Buttari, L Combe, V Dolean, M Gerest, G Guo, P Jolivet, J-Y L'Excellent, F Mamfoumbi, T Mary, C Puglisi, A Ribodetti, P-H Tournier "Is 3D frequency-domain FWI of full-azimuth/long-offset OBN data feasible? The Gorgon data FWI case study" The Leading Edge 42 (3), 173-183, 2023 The outcomes resulting from this collaboration have also been presented at a few major conferences: - The contribution we submitted to the SEG Annual Event (https://seg.org/am/2020) a yearly world event of the geophysical community, has been presented at the virtual conference that took place online in October 2020 V Dolean, PH Tournier, P Jolivet, S Operto, "Large-scale frequency-domain seismic wave modeling on h-adaptive tetrahedral meshes with iterative solver and multi-level domain-decomposition preconditioners", SEG Technical Program Expanded Abstracts 2020, 2683-2688. - The contribution we submitted to the EAGE conference (https://eage.eventsair.com/eageannual2020/), a recurrent reference European event for the geophysical community, has been presented at the virtual conference that took place online in December 2020 V Dolean, P Jolivet, P Tournier, S Operto, Iterative frequency-domain seismic wave solvers based on multi-level domain-decomposition preconditioners, 82nd EAGE Annual Conference & Exhibition 2020 (1), 1-5 - The contribution we submitted to the WCCM-ECCOMAS 2020 conference (https://www.wccm-eccomas2020.org/frontal/) has been presented at the virtual event that took place January 2021. |
| Start Year | 2019 |
| Description | Frequency-domain seismic wave modelling based upon multi-level domain-decomposition preconditioners |
| Organisation | University of Toulouse |
| Country | France |
| Sector | Academic/University |
| PI Contribution | This work was done in collaboration with: - Stéphane Operto, CNRS senior researcher at the Géoazur Laboratory (part of Observatoire de la Côte d'Azur), member of the University Côte d'Azur - Pierre-Henri Tournier, CNRS research engineer at Sorbonne University - Pierre Jolivet, CNRS junior researcher at the University of Toulouse (now in Sorbonne University) on the application of fast solvers to realistic geophysical problems. Two-level preconditionners developed by our team have been applied to difficult benchmark problems in geophysical applications. |
| Collaborator Contribution | Pierre-Henri Tournier and Pierre Jolivet have performed extensive tests on parallel computers to assess the performance of the method Stéphane Operto provided the benchmark problems and brought the expertise on the applications side. |
| Impact | This is a multidisciplinary collaboration: geophysics, computer science and mathematics. A paper was accepted for publication on Geophysics: - PH Tournier, P Jolivet, V Dolean, HS Aghamiry, S Operto, S Riffo, "3D finite-difference and finite-element frequency-domain wave simulation with multilevel optimized additive Schwarz domain-decomposition preconditioner: A tool for full-waveform inversion of sparse node data sets", Geophysics 87 (5), T381-T402. Moreover a case study on a realistic application was recently published in Leading Edge (main communication journal for the geophysical community) - S Operto, P Amestoy, H Aghamiry, S Beller, A Buttari, L Combe, V Dolean, M Gerest, G Guo, P Jolivet, J-Y L'Excellent, F Mamfoumbi, T Mary, C Puglisi, A Ribodetti, P-H Tournier "Is 3D frequency-domain FWI of full-azimuth/long-offset OBN data feasible? The Gorgon data FWI case study" The Leading Edge 42 (3), 173-183, 2023 The outcomes resulting from this collaboration have also been presented at a few major conferences: - The contribution we submitted to the SEG Annual Event (https://seg.org/am/2020) a yearly world event of the geophysical community, has been presented at the virtual conference that took place online in October 2020 V Dolean, PH Tournier, P Jolivet, S Operto, "Large-scale frequency-domain seismic wave modeling on h-adaptive tetrahedral meshes with iterative solver and multi-level domain-decomposition preconditioners", SEG Technical Program Expanded Abstracts 2020, 2683-2688. - The contribution we submitted to the EAGE conference (https://eage.eventsair.com/eageannual2020/), a recurrent reference European event for the geophysical community, has been presented at the virtual conference that took place online in December 2020 V Dolean, P Jolivet, P Tournier, S Operto, Iterative frequency-domain seismic wave solvers based on multi-level domain-decomposition preconditioners, 82nd EAGE Annual Conference & Exhibition 2020 (1), 1-5 - The contribution we submitted to the WCCM-ECCOMAS 2020 conference (https://www.wccm-eccomas2020.org/frontal/) has been presented at the virtual event that took place January 2021. |
| Start Year | 2019 |
| Description | Gaussian states for the approximation of Helmholtz equation |
| Organisation | INRIA Nice |
| Country | France |
| Sector | Academic/University |
| PI Contribution | We have recently started a collaboration with T. Chaumont-Frelet (Inria) and M. Ingremeau (Univ. Cote d'Azur) on the use of different basis functions (Gaussian states) that could lead to an important reduction of degrees of freedom for the approximation of the Helmholtz equation. |
| Collaborator Contribution | This is an intra disciplinary collaboration (numerical analysis-scientific computing-semi classical analysis) in which tools from semi-classical analysis have been successfully applied to numerical analysis thus leading to better methods. |
| Impact | A paper has been recently submitted for publication and is now available as a preprint: Théophile Chaumont-Frelet, Victorita Dolean, Maxime Ingremeau, Efficient approximation of high-frequency Helmholtz solutions by Gaussian coherent states, https://arxiv.org/abs/2208.04851, 2022 Talks on this topic were given at the ICMS conference "Solvers for frequency-domain wave problems and applications" (June 2022, Glasgow) and also at Oberwolfach workshop "At the Interface between Semiclassical Analysis and Numerical Analysis of Wave Scattering Problems", (September 2022). |
| Start Year | 2021 |
| Description | Physics Informed Neural Networks for Waves |
| Organisation | Delft University of Technology (TU Delft) |
| Country | Netherlands |
| Sector | Academic/University |
| PI Contribution | Motivated by the latest developments in the field of Scientific Machine Learning, we have recently started a collaboration with A. Heinlein (TU Delft), B. Moseley, S. Mishra (ETH Zurich) on the use of neural networks for PDEs with a focus on waves. |
| Collaborator Contribution | We have obtained a few very encouraging preliminary results that were very welcome by the community. They were successively presented at the IMG22 conference in Lugano, DD27 conference in Prague and in various seminars and local events (e.g. RAL-Oxford seminar or AI for Waves in Nice). A. Heinlein visited Strathclyde twice in 2022 and we interacted via zoom with B. Moseley and S. Mishra. |
| Impact | We have a preprint that has recently been accepted for publication in the proceedings of the DD27 conference on domain decomposition methods. V Dolean, A Heinlein, S Mishra, B Moseley, Finite basis physics-informed neural networks as a Schwarz domain decomposition method, arXiv:2211.05560, 2022 |
| Start Year | 2022 |
| Description | Physics Informed Neural Networks for Waves |
| Organisation | ETH Zurich |
| Country | Switzerland |
| Sector | Academic/University |
| PI Contribution | Motivated by the latest developments in the field of Scientific Machine Learning, we have recently started a collaboration with A. Heinlein (TU Delft), B. Moseley, S. Mishra (ETH Zurich) on the use of neural networks for PDEs with a focus on waves. |
| Collaborator Contribution | We have obtained a few very encouraging preliminary results that were very welcome by the community. They were successively presented at the IMG22 conference in Lugano, DD27 conference in Prague and in various seminars and local events (e.g. RAL-Oxford seminar or AI for Waves in Nice). A. Heinlein visited Strathclyde twice in 2022 and we interacted via zoom with B. Moseley and S. Mishra. |
| Impact | We have a preprint that has recently been accepted for publication in the proceedings of the DD27 conference on domain decomposition methods. V Dolean, A Heinlein, S Mishra, B Moseley, Finite basis physics-informed neural networks as a Schwarz domain decomposition method, arXiv:2211.05560, 2022 |
| Start Year | 2022 |
| Description | Robust solvers for positive Maxwell's equations |
| Organisation | Sorbonne University |
| Country | France |
| Sector | Academic/University |
| PI Contribution | Together with Niall Bootland, we are currently working on a project with Frederic Nataf (senior researcher) and Pierre-Henri Tournier (research engineer) both from Sorbonne University. We aim at improving the two-level preconditioners for heterogeneous Maxwell problems. Niall Bootland and Victorita Dolean have visited Sorbonne University in Paris in December 2021. We have preprint of our ongoing work that has also been presented at the 26th international conference on domain decomposition methods: N Bootland, V Dolean, F Nataf, PH Tournier, Two-level DDM preconditioners for positive Maxwell equations, arXiv preprint arXiv:2012.02388 |
| Collaborator Contribution | Frederic Nataf is an expert in domain decomposition methods and Pierre-Henri Tournier is at the developper of the domain decomposition library ffddm (https://doc.freefem.org/documentation/ffddm/index.html) |
| Impact | As mentioned above, we have a preprint and we are currently finalising a research paper on the topic. The work has also been presented at the forthcoming International Conference on Domain Decomposition Methods in Prague, July 2022 (invited speaker in a mini-symposium). |
| Start Year | 2020 |
| Description | Scalar solvers for complex diffusion problems |
| Organisation | University of Geneva |
| Country | Switzerland |
| Sector | Academic/University |
| PI Contribution | Together with Alex Kyriakis (former PhD student at Strathclyde, now PDRA at the University of Loughborough), we worked with Prof. Martin J. Gander from the University of Geneva on scalable solvers for complex diffusion problems as they arise in low frequency applications in electrical engineering. We had regular online meetings via zoom with Prof. Gander. Victorita Dolean has visited Prof. Gander several times in Geneva in the beginning of 2022. |
| Collaborator Contribution | Prof. Martin J. Gander is one of the world leaders in domain decomposition methods and more particularly in wave propagation problems. |
| Impact | We presented a common contribution at the 26th International Conference on Domain decomposition methods in December 2020 and this contribution was accepted for publication in the conference proceedings. V. Dolean, M.J. Gander, A. Kyriakis, "Optimizing transmission conditions for multiple subdomains in the Magnetotelluric Approximation of Maxwell's equations", https://arxiv.org/abs/2103.07879, 2021. Alex Kyriakis has defended his PhD viva in September 2021 and the thesis has been published in the final form in the first quarter of 2022. https://stax.strath.ac.uk/concern/theses/2227mq25p A submitted paper was recently accepted for publication in the SIAM Journal on Scientific Computing: V. Dolean, M.J. Gander, A. Kyriakis, "Closed form optimized transmission conditions for complex diffusion with many subdomains", https://arxiv.org/abs/2204.09754 |
| Start Year | 2020 |
| Description | Spectral coarse spaces for indefinite problems |
| Organisation | Heidelberg University |
| Country | Germany |
| Sector | Academic/University |
| PI Contribution | We have engaged in substantial discussions about the performance of the GENEO preconditioner for indefinite and non-self-adjoint problems. The team of I.G. Graham (Bath), V. Dolean and N. Bootland (Strathclyde) and R. Scheichl and C. Ma (Heidelberg) have collaborated on this topic. The initial discussions took place at CIRM in Luminy at a conference whose organisers included V Dolean (Strathclyde), in September 2019. Two publications have now resulted: N. Bootland, V. Dolean, I. G. Graham, C. Ma, R. Scheichl, "GenEO coarse spaces for heterogeneous indefinite elliptic problems", appeared in proceedings of 26th Domain Decomposition Conference". N. Bootland, V. Dolean, I. G. Graham, C. Ma and R. Scheichl, Overlapping Schwarz methods with GenEO coarse spaces for indefinite and non-self-adjoint problems, appeared in IMA Journal on Numerical Analysis, 2022. |
| Collaborator Contribution | Bath and Heidelberg are collaborating as above. We have regular online meetings to expedite progress. The collaboration between Bath and Strathclyde is continuing, through the Strathclyde PhD project of M. Fry, supervised by V. Dolean and M. Langer in which I.G. Graham is involved in the discussions. |
| Impact | The outputs are given above (available as preprints) - N. Bootland, V. Dolean, I. G. Graham, C. Ma, R. Scheichl, GenEO coarse spaces for heterogeneous indefinite elliptic problems, proceedings of 26th Domain Decomposition Conference, https://arxiv.org/abs/2103.16703, 2021. - N. Bootland, V. Dolean, I. G. Graham, C. Ma and R. Scheichl, Overlapping Schwarz methods with GenEO coarse spaces for indefinite and non-self-adjoint problems, IMA Journal on Numerical Analysis, 2022. |
| Start Year | 2019 |
| Description | Spectral coarse spaces for indefinite problems |
| Organisation | University of Bath |
| Department | Department of Mathematical Sciences |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We have engaged in substantial discussions about the performance of the GENEO preconditioner for indefinite and non-self-adjoint problems. The team of I.G. Graham (Bath), V. Dolean and N. Bootland (Strathclyde) and R. Scheichl and C. Ma (Heidelberg) have collaborated on this topic. The initial discussions took place at CIRM in Luminy at a conference whose organisers included V Dolean (Strathclyde), in September 2019. Two publications have now resulted: N. Bootland, V. Dolean, I. G. Graham, C. Ma, R. Scheichl, "GenEO coarse spaces for heterogeneous indefinite elliptic problems", appeared in proceedings of 26th Domain Decomposition Conference". N. Bootland, V. Dolean, I. G. Graham, C. Ma and R. Scheichl, Overlapping Schwarz methods with GenEO coarse spaces for indefinite and non-self-adjoint problems, appeared in IMA Journal on Numerical Analysis, 2022. |
| Collaborator Contribution | Bath and Heidelberg are collaborating as above. We have regular online meetings to expedite progress. The collaboration between Bath and Strathclyde is continuing, through the Strathclyde PhD project of M. Fry, supervised by V. Dolean and M. Langer in which I.G. Graham is involved in the discussions. |
| Impact | The outputs are given above (available as preprints) - N. Bootland, V. Dolean, I. G. Graham, C. Ma, R. Scheichl, GenEO coarse spaces for heterogeneous indefinite elliptic problems, proceedings of 26th Domain Decomposition Conference, https://arxiv.org/abs/2103.16703, 2021. - N. Bootland, V. Dolean, I. G. Graham, C. Ma and R. Scheichl, Overlapping Schwarz methods with GenEO coarse spaces for indefinite and non-self-adjoint problems, IMA Journal on Numerical Analysis, 2022. |
| Start Year | 2019 |
| Description | Two-level solvers for Helmholtz problems |
| Organisation | Delft University of Technology (TU Delft) |
| Country | Netherlands |
| Sector | Academic/University |
| PI Contribution | During an event organised by the University of Strathclyde "International Strategic Partnerships Strathclyde/TU Delft scoping workshop" Ross Priory, 20/21 November 2019, a discussion has been initiated with Prof. Kees Vuik from the University of Delft and a collaboration has started soon after on the development of two-level methods for Helmholtz equations. Researchers involved: Kees Vuik, Vandana Dwarka (Delft), V. Dolean and N. Bootland (University of Strathclyde). |
| Collaborator Contribution | Kees Vuik, Vandana Dwarka (TU Delft) and V. Dolean, N. Bootland (Strathclyde) had regular online meetings. Partners from Delft will applied their method on data (from in-house numerical simulation codes) provided by Strathclyde. |
| Impact | We have co-organised the mini-symposium 'Scalable Solvers for the Helmholtz Problem' at the SIAM CSE 2021 (https://www.siam.org/conferences/cm/conference/cse21) that took place virtually from 1-5 March 2021. Our common work was also presented at the 26th International Conference on Domain decomposition methods and was accepted for publication in the conference proceedings: Niall Bootland, Vandana Dwarka, Pierre Jolivet, Victorita Dolean, Cornelis Vuik Inexact subdomain solves using deflated GMRES for Helmholtz problems, https://arxiv.org/abs/2103.17081, 2021. |
| Start Year | 2019 |
| Description | Invited talk in a mini symposium (DD27 conference, Prague) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | I was an invited to give a talk in the mini-symposium "Efficient solvers for Maxwell's equations" |
| Year(s) Of Engagement Activity | 2022 |
| URL | https://www.dd27.cz/program/minisymposia |
| Description | Invited talk in a mini-symposium (IMG22 conference, Lugano) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Postgraduate students |
| Results and Impact | Invited to give a talk in a mini-symposium "Combining the domain decomposition and the multilevel methods with machine learning approaches" |
| Year(s) Of Engagement Activity | 2022 |
| URL | https://www.img2022.usi.ch |
| Description | Invited talk in a mini-symposium - ECCOMAS conference (Oslo, Norway) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | I gave an invited talk in a mini-symposium at the ECCOMAS conference on "Spectral coarse spaces for indefinite and non-self adjoint problems" in front of an audience of researchers and PhD students. |
| Year(s) Of Engagement Activity | 2022 |
| Description | Invited to give talk in PinT22 (Marseille, France) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | I gave an invited talk on "Schwarz waveform relaxation methods for semi-linear advection diffusion systems" in front of an audience (between 60-80 people) of researchers and post-graduate students. |
| Year(s) Of Engagement Activity | 2022 |
| URL | https://conferences.cirm-math.fr/2642.html |
| Description | Organisation of a mini-symposium (DD27 conference, Prague) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Organisation of a mini-symposium on "Spectral Coarse Spaces in Domain Decomposition Methods and Multiscale Discretizations" |
| Year(s) Of Engagement Activity | 2023 |
| URL | https://www.dd27.cz/program/minisymposia |
| Description | Organisation of a mini-symposium at the 26th International Conference on Domain decomposition methods (held virtually) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | I have co-organised the mini-symposium "Preconditioning Methods for Frequency Domain Wave Problems". Around 30 participants from the conference have attended this session. The main purpose was to gather international researchers working on this topic but also disseminate the results obtained in the project so far. |
| Year(s) Of Engagement Activity | 2020 |
| URL | https://www.math.cuhk.edu.hk/conference/dd26/?Scientific_Program-Minisymposia |
| Description | Organisation of a mini-symposium at the SIAM CSE21 conference (held virtually) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | I hava co-organised the mini-symposium entitled "Scalable Solvers for the Helmholtz Problem" at the SIAM Computational Science and Engineering 2021. Around 30 participants from the conference have attended this session. The main purpose was to gather international researchers working on this topic but also disseminate the results obtained in the project so far. |
| Year(s) Of Engagement Activity | 2021 |
| Description | Organisation of an international workshop |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Study participants or study members |
| Results and Impact | As agreed in the project plan we organised an international workshop to disseminate the results of our project to other international researchers. This took place in Glasgow from June 20-24 2022 and was supported by International Centre for Mathematical Sciences (£24,000 plus admin support), Glasgow Mathematical Journal Trust (£4,000) and LMS (£ 5,292) . Thanks to this funding we were able to support the travel and subsistence of all participants. This workshop had 43 participants was was a huge success, as indicated by uniformly positive responses in the post-workshop questionnaire administered by ICMS. The professional admin support provided by ICMS allowed the organisers (V. Dolean, I.G. Graham, S. Gazzola and E. Spence) to concentrate on the scientific activity for the entirety of the workshop. |
| Year(s) Of Engagement Activity | 2022 |
| Description | Parallel Solution Methods for Systems Arising from PDEs |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | V. Dolean was one of the organisers of the international workshop "Parallel Solution Methods for Systems Arising from PDEs" which took place in CIRM (International Centre of Mathematical Meetings) in Marseille from 16-20 September 2019. This meeting gathered around 60 participants, well known international researchers in the broad field of parallel iterative solvers. Four others members of our EPSRC project took part in this meeting (I.G. Graham, S. Gong, N. Bootland and A. Kyriakis) which contributed to active exchanges and to setting plans and new collaborations for the future research activity. |
| Year(s) Of Engagement Activity | 2019 |
| Description | Stakeholders meeting for this project |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Industry/Business |
| Results and Impact | On October 7 2019, in collaboration with Prof. Ivan G. Graham from Bath, we have organised the first Stakeholders meeting for our grant. Attendees included industrialists from Schlumberger and ABB, software developers from Imperial College and Toulouse as well as the academic members, collaborators of the project, PDRAs and research students from our teams (Strathclyde and Bath). |
| Year(s) Of Engagement Activity | 2019 |