Dr. Erdem Altuntac
'Everything should be made as simple as possible, but not simpler.'
I am currently research scientist at Fraunhofer FHR after my 2 years of PostDoc research at the Universite Libre de Bruxelles, under the supervision of Prof. Dr. I. Loris. I obtained my Ph.D. in April 2016 under the supervision of Prof. Dr. D. R. Luke and Prof. Dr. T. Hohage. My detailed scientific activities are below.
Modeling & Algorithms
'Everything should be made as simple as possible, but not simpler.'Albert Einstein.
- Orthogonal representation bases, i.e. wavelets, DCT, DFT
- Image based dictionaries
- Conventional quadratic-Tikhonov regularization
- Gradient-based algorithms
- Primal-dual splitting
- Proximal mapping
- Rules for the choice of the regularization parameter
- Convergence analysis (with the assumption of Variational Source Condition).
- Depth completion from LiDAR based point-cloud data
- Image inpainting
- Computational image recovery
- Multidimensional tomographic image reconstruction; e.g. 3D atmospheric tomography
- Situational awareness by acoustics
- Parameter estimation in non-linear acoustics
- Cwalina, S., Kottke, C., Jungnickel, V., Freund, R., Runge, P., Rustige, P., Knieling, T., Gu-Stoppel, S., Albers, J., Laske, N., Senger, F., Wen, L., Giovanneschi, F., Altuntac, E., Rames, A. N., Huici, M. A. G., Küter, A., Reddy, S. Fiber-based frequency modulated LiDAR with MEMS scanning capability for long-range sensing inautomative applications. (to be presented at IEEE MetroAutomotive Workshop 2021) .
- Altuntac, E. Choice of the Parameters in A Primal-Dual Algorithm for Bregman Iterated Variational Regularization.
https://doi.org/10.1007/s11075-020-00909-6 Numer Algor 86, 729–759 (2021).
- New Pair of Primal Dual Algorithms for Bregman Iterated Variational Regularization.
https://arxiv.org/abs/1903.07392 March 2019.
- Altuntac, E. Variational Regularization Strategy for Atmospheric Tomography
Institute for Numerical and Applied Mathematics, University of Goettingen, July 2016.
- Altuntac, E. Generalized Variational Source Condition Associated with the Bregman Distance-I: Verification of the Variational Source Condition and Stability of the Total Error Estimation.
https://arxiv.org/abs/1606.03650 . July 2016.
- Altuntac, E. Quasi-Newton Approach for an Atmospheric Tomography Problem.
https://arxiv.org/abs/1511.08022 April 2016.
- Altuntac E. On convergence of an alternating method for a Cauchy problem for the Helmholtz equation.
https://www.impan.pl/wydawnictwa/preprints_impan/p730.pdf IMPAN preprint 730, June 2011.
During my doctoral studies, I have developed a special interest in coding up and implementation of some numerical tools that have been beneficial to my research. Addition to the list below, I have also performed some test implementations for the software SAMSARA developed by D. R. Luke.
- Primal-dual splitting for Bregman iterated variational regularization , March 2019.
- A Prototype for 3-D Atmospheric Tomography - II , March 2019.
- 3-D Smooth TV Functional and Its Gradient , August 2015.
- A Prototype for 3-D Atmospheric Tomography , August 2015.
- Basic 2-D Reconstruction Instruments , May 2014.
- AIP-2019 - Applied Inverse Problems Conference July, 08th - 12th, 2019, Grenoble - France (talk)
- Finnish Inverse Problems Summer School 2019 - June, 3 - 7, 2019, Helsinki, Finland
- FNRS Contact Group "Wavelets and applications", November 7, 2018, Universite Libre de Bruxelles, Brussels - Belgium (talk)
- IFIP TC 7-Conference on System Modelling and Optimization, July 23-27, 2018, Essen - Germany (talk)
- Inverse Problems in Wave Propagation - IWaP-2015, April 7-10, 2015. University of Bremen, Bremen/Germany. (poster presentation)
- Recent Progress in Mathematical and Numerical Analysis of Inverse Problems, May 19-23, 2014. CIRM, Marseille/France. (poster presentation)
- Inverse Problems: IP-TA 2010, Developments in Theory and Application, February 9-12, 2010. Institute of Mathematics of The Polish Academy of Sciences, Warsaw/Poland.
- September 2019 - present; Research Scientist, Cognitive Radar, Fraunhofer FHR, Bonn / Germany.
- October 2017 - September 2019t; Post-Doctoral Researcher, Department of Mathematics, Université libre de Bruxelles, Brussels / Belgium.
- August 2016 - August 2017 (resigned); Research scientist, Microflown Avisa, Arnhem/Netherlands.
- September 2015 - January 2016; Research assistant, Institute for Numerical and Applied Mathematics, University of Göttingen. Göttingen/Germany.
- March 2015 - August 2015; Research assistant, Institute of Mathematics, University of Göttingen. Göttingen/Germany.
- February 2012 - February 2015; Research scientist, German Federal Weather Service, Research and Development, Data Assimilation Unit, Offenbach am Main/Germany.
- September 2009 - September 2010; Research assistant, Institute of Mathematics of The Polish Academy of Sciences, Numerical Analysis Laboratory, Warsaw/Poland.
- Computer Skills/Experiences: MATLAB, Linux Ubuntu/openSUSE, Mac OS.
- Hobbies: Chess, The game of GO, Aikido (3rd Kyu by the Aikido dojo Frankfurt), Brazilian Jiu-Jitsu (2nd degree white belt by ICON BJJ Brussels)