Agenda
DCSE/SIAM Seminar
- Wednesday, 24 May 2017
- 11:00-12:00
- EWI Lipkenszaal
Untangling nonlinearity in inverse scattering with data-driven reduced order models
Vladimir DruskinSchlumberger-Doll, Boston
We consider an inverse problem for the acoustic wave equation, where an array of sensors probes an unknown medium with pulses and measures the scattered waves. The goal is to determine from these measurements the structure of the scattering medium, modeled by a spatially varying acoustic impedance function.
Many inversion algorithms assume that the mapping from the unknown impedance to the scattered waves is approximately linear. The linearization, known as the Born approximation, is not accurate in strongly scattering media, where the waves undergo multiple reflections before they reach the sensors in the array. Thus, the reconstructions of the impedance have numerous artifacts. In this talk we show that it is possible to remove the multiple scattering effects from the data registered at the array, using a reduced order model (ROM). The ROM is defined by an orthogonal projection of the wave propagator operator on the subspace spanned by the time snapshots of the solution of the wave equation. The snapshots are known only at the sensor locations, which is enough information to construct the ROM. The main result of the paper is a novel algorithm that uses the ROM to map the data to its Born approximation. We develop the algorithm from first principles and demonstrate its accuracy with numerical simulations.
Agenda
- Thu, 25 Apr 2024
- 15:30
- EEMCS, Snijderszaal
Microelectronics colloquium
Achilleas Savva
Regenerative Bioelectronic Technologies - #ReBooT
'Regenerative Bioelectronics' merges insights from two distinct research domains: stem cell-based regenerative medicine and bioelectronic engineering. The great therapeutic potential of stem cells to give solutions to untreated neurological disorders, has recently been verified by clinical trials in human
- Mon, 6 May 2024
- 12:30
- Aula Senaatszaal
PhD Thesis Defence
Christoph Manss
Multi-agent exploration under sparsity constraints
- Tue, 21 May 2024
- 10:00
- Aula Senaatszaal
PhD Thesis Defence
Wangyang Yu
- 27 -- 28 May 2024
- Aula, TU Delft
Conferences
44th Benelux Symposium on Information Theory and Signal Processing (SITB'24, Delft)
- Tue, 18 Jun 2024
- 15:00
- Aula Senaatszaal
PhD Thesis Defence
Hanie Moghaddasi
Model-based feature engineering of atrial fibrillation
- Mon, 24 Jun 2024
- Aula, TU Delft
Conferences
7th Graph Signal Processing Workshop (GSP 2024)
- Wed, 10 Jul 2024
- 10:00
- Aula Senaatszaal