# Christian Clason: Vorträge

## Konferenzen

**Iterative regularization of nonsmooth ill-posed problems**,

12th International Scientific Conference and Young Scientist School "Theory and Computational Methods for Inverse and Ill-posed Problems", Novosibirsk, Akademgorodok, October 4-10, 2020 (online).**Convex relaxation of hybrid discrete-continuous control problems**,

SIGOPT 2020 International Conference on Optimization, TU Dortmund, March 4-6, 2020.**Multibang regularization of a coefficient inverse problem for the wave equation**,

Computational Methods for New Directions in Inverse Problems, Texas A&M University, College Station, TX, USA, February 3-5, 2020.**Convex relaxation of hybrid discrete-continuous control problems**,

First Indo-German Conference on Computational Mathematics, Indian Institute of Science, Bangalore, India, December 2-4, 2019.**Iterative regularization for nonsmooth inverse problems**,

1st Alps-Adriatic Inverse Problems Workshop, Klagenfurt, Austria, November 7-8, 2019.**Optimal control of nonsmooth equations**,

Workshop "New Trends in PDE-Constrained Optimization", Special Semester on Optimization, RICAM Linz, Austria, November 14-18, 2019.**Optimal control of the principal coefficient in a scalar wave equation**,

19th French-German-Swiss Conference on Optimization, Nice, France, September 17-20, 2019.**Discrete material optimization for the wave equation**,

International Conference on Continuous Optimization, Berlin, Germany, August 5-8, 2019.**Iterative regularization for nonsmooth inverse problems**,

International Congress on Industrial and Applied Mathematics, Valencia, Spain, July 15-19, 2019.**Iterative regularization of non-smooth equations**,

Applied Inverse Problems Conference, Grenoble, France, July 8-12, 2019.**Multibang regularization of a coefficient inverse problem for the wave equation**,

Applied Inverse Problems Conference, Grenoble, France, July 8-12, 2019.**Accelerated primal-dual methods for structured non-convex optimization**,

International Conference on Stochastic Optimization and Related Topics, Mülheim an der Ruhr, Germany, April 26-26, 2019.**Multibang regularization of a coefficient inverse problem for the wave equation**,

"Workshop “Mathematical and Numerical Approaches for Multi-Wave Inverse Problems”, CIRM, Marseille, France, April 1-5, 2019.**Iterative regularization of non-smooth equations**,

Workshop "Numerical Methods for Optimal Control and Inverse Problems", Technische Universität München, Germany, March 11-13, 2019.**Accelerated primal-dual methods for PDE-constrained optimization**,

International Workshop on PDE-constrained Optimization, Optimal Control, and Applications , Tsinghua Sanya International Mathematics Forum, Hainan, China, December 10-14, 2018.**Bouligand-Landweber iteration for a non-smooth ill-posed problem**,

COPDESC Workshop "Analysis, Control and Inverse Problems for PDEs", Napoli, Italy, November 26-30, 2018.**Convex regularization of discrete-valued inverse problems**,

2018 Joint Meeting of the Korean Mathematical Society and the German Mathematical Society., Seoul, Korea, October 3-6, 2018.**Bouligand-Landweber iteration for a non-smooth ill-posed problem**,

VI Latin American Workshop on Optimization and Control, Quito, Ecuador, September 3-7, 2018.**Bouligand-Landweber iteration for a non-smooth ill-posed problem**,

27th IFIP TC7 Conference on System Modelling and Optimization, Essen, Germany, July 23-27, 2018.**Convex regularization of discrete-valued inverse problems**,

Inverse Problems: Modeling and Simulation, Mellieha, Malta, May 21-25, 2018.**Total variation regularization of multi-material topology optimization**,

7th International Conference on High Performance Scientific Computing", Hanoi, Vietnam, March 19-23, 2018.**Design of optimal RF pulses for NMR as a discrete-valued control problem**,

9th Vienna International Conference on Mathematical Modelling, TU Wien, Vienna, Austria, February 21-23, 2018.**Convex regularization of discrete-valued inverse problems**,

Workshop "New Trends in Parameter Identification for Mathematical Models", IMPA, Rio de Janeiro, Brazil, October 30-November 3, 2017.**Total variation regularization of multi-material topology optimization**,

IFIP WG 7.2 Workshop "Optimal Control of Partial Differential Equations", Castro Urdiales, Spain, September 18-21, 2017.**Convex relaxation of hybrid discrete-continuous control problems**,

19th ÖMG Congress and DMV Annual Meeting, Salzburg, Austria, September 11-15, 2017.**Convex regularization of discrete-valued inverse problems**,

Workshop "Variational methods and effective algorithms for imaging and vision", Isaac Newton Institute, Cambridge, UK, September 4-8, 2017.**Discrete regularization of parameter identification problems**,

Workshop "Computational Imaging and Tomography", Innsbruck, Austria, August 17-18, 2017.**Discrete regularization of parameter identification problems**,

Applied Inverse Problems Conference, Hangzhou, China, May 29-June 2, 2017.**Adaptive discretization and first-order methods for nonsmooth inverse problems for PDEs**,

Turing/LMS Workshop "Inverse Problems and Data Science", Edinburgh, UK, May 8-10, 2017.**Convex relaxation of hybrid discrete-continuous control problems**,

Workshop "Numerical Methods for Optimal Control and Inverse Problems", Technische Universität München, Germany, April 5-7, 2017.**A primal-dual extragradient method for nonlinear inverse problems for PDEs**,

Optimization Techniques for Inverse Problems III, Modena, Italy, September 19-21, 2016.**A nonlinear primal-dual extragradient method for nonsmooth PDE-constrained optimization**,

IFIP Workshop "Optimal Control Meets Inverse Problems", Essen, September 5-9, 2016.**A nonlinear primal-dual extragradient method for nonsmooth PDE-constrained optimization**,

5th International Conference on Continuous Optimization, Tokyo, Japan, August 8-11, 2016.**Nonsmooth optimization of partial differential equations**,

XII International Conference Approximation and Optimization in the Caribbean, La Habana, Cuba, June 6-10, 2016.**A primal-dual extragradient method for nonlinear forward models in function spaces**,

SIAM Conference on Imaging Science, Albuquerque, New Mexico, May 23-26, 2016.**Second-order analysis of pointwise subdifferentials and applications to nonsmooth optimization**,

Workshop on Nonsmooth and Stochastic Optimization with Applications to Energy Management, WIAS, Berlin, May 10-12, 2016.**Stochastic inverse problems with impulsive noise**,

SIAM Conference on Uncertainty Quantification, Lausanne, Switzerland, April 5-8, 2016.**Convex regularization of hybrid discrete-continuous inverse problems**,

International Workshop on Recent Developments in Inverse Problems, Berlin, Germany, September 17-18, 2015.**Convex regularization of hybrid discrete-continuous inverse problems**,

8th International Congress on Industrial and Applied Mathematics, Beijing, China, August 10-14, 2015.**A primal-dual extragradient method for nonsmooth nonlinear inverse problems for PDEs**,

International Conference on Inverse Problems, Imaging, and Applications, Hangzhou, China, August 6-8, 2015.**A primal-dual extragradient method for nonlinear operators in function spaces**,

27th IFIP TC7 Conference, Sophia Antipolis, France, June 29-July 3, 2015.**A convex analysis approach to multi-material topology optimization**,

International Workshop "From Open to Closed Loop Control", Mariatrost, Austria, June 22-26, 2015.**Stochastic inverse problems with impulsive noise**,

Applied Inverse Problems Conference, Helsinki, Finland, May 25-29, 2015.**A convex analysis approach to switching control of PDEs**,

International Conference on Inverse Problems and Optimal Control, Hong Kong, China, December 4-6, 2014.**Stochastic inverse problems with impulsive noise**,

Chemnitz Symposium on Inverse Problems, Chemnitz, Germany, September 18-19, 2014.**Convex relaxation of hybrid binary-continuous problems**,

Inverse Problems - from Theory to Application, Bristol, UK, August 26-28, 2014.**Avoiding degeneracy in the Westervelt equation by state constrained optimal control**,

10th AIMS Conference on Dynamical Systems, Differential Equations and Applications, Madrid, Spain, July 7-11, 2014.**A convex analysis approach to hybrid binary-continuous optimal control problems with application to switching control**,

10th AIMS Conference on Dynamical Systems, Differential Equations and Applications, Madrid, Spain, July 7-11, 2014.**Multi-bang control of elliptic equations**,

SIAM Conference on Optimization, San Diego, California, May 19-22, 2014.**Multi-bang control of elliptic equations**,

Workshop "Numerical Methods for Optimal Control and Inverse Problems", Technische Universität München, Germany, March 3-5, 2014.**Sparse controls for elliptic and parabolic partial differential equations**,

1st IFAC Workshop on Control of Systems Modeled by PDEs, Paris, France, September 25-27, 2013.**Parameter identification problems with uniform noise**,

26th IFIP TC7 Conference, Klagenfurt, Austria, September 8-13, 2013.**Multi-bang control of elliptic systems**,

4th International Conference on Continuous Optimization, Lisboa, Portugal, July 29-August 1, 2013.**Parameter identification problems with uniform noise**,

3rd European Conference on Computational Optimization, Chemnitz, Germany, July 17-19, 2013.**Coefficient inverse problems with uniform noise**,

Applied Inverse Problems Conference, Daejeon, South Korea, July 1-5, 2013.**Optimal control of elliptic PDEs with positive measures**,

Workshop "Numerical Methods for Optimal Control and Inverse Problems", Technische Universität München, Germany, March 11-13, 2013.**Parameter identification with non-Gaussian noise**,

Oberwolfach Workshop "Computational Inverse Problems", Mathematisches Forschungsinstitut Oberwolfach, Germany, October 22-26, 2012.**Inverse problems for PDEs with uniform noise**,

21st International Symposium on Mathematical Programming, Berlin, Germany, August 20-24, 2012.**Inverse problems for PDEs with L-infinity data fitting**,

Inverse Problems: Modeling and Simulation, Antalya, Turkey, May 21-25, 2012.**Inverse problems with uniform noise**,

Workshop "Numerical Methods for Optimal Control and Inverse Problems", Technische Universität München, Germany, March 12-14, 2012.**A measure space approach to optimal source placement**,

Workshop "Optimization with PDE constraints", Charles University Prague, Czech Republic, December 9-10, 2011.**Variational methods for image reconstruction in magnetic resonance imaging**,

Dagstuhl Seminar "Efficient Algorithms for Global Optimisation Methods in Computer Vision", Schloss Dagstuhl, Germany, November 20-25, 2011.**Minimum effort optimal control of elliptic PDEs**,

25th IFIP TC 7 Conference, Berlin, Germany, September 12-16, 2011.**A measure space approach to optimal source placement**,

25th IFIP TC 7 Conference, Berlin, Germany, September 12-16, 2011.**Autocalibrated parameter choice for non-smooth noise models**,

Applied Inverse Problems Conference, Texas A&M University, College Station, Texas, USA, May 23-27, 2011.**L1 data fitting for parameter identification problems for PDEs**,

Applied Inverse Problems Conference, Texas A&M University, College Station, Texas, USA, May 23-27, 2011.**Parameter identification problems for PDEs with L1 data fitting**,

SIAM Conference on Optimization, Darmstadt, Germany, May 16-19, 2011.**Optimal source placement as an optimal control problem in measure spaces**,

82nd Annual Meeting of the GAMM, Graz, Austria, April 18-21, 2011.**L1 data fitting for nonlinear inverse problems**,

Chemnitz Symposium on Inverse Problems, Chemnitz, Germany, September 23-24, 2010.**Total variation regularized nonlinear inversion for parallel MRI with variable density sampling patterns**,

Workshop on Novel Reconstruction Strategies in NMR and MRI, Göttingen, Germany, September 9-11, 2010.

[movies (mp4): slide 22, slide 23]**Inverse source problems with L1-type penalties**,

Inverse Problems: Modeling and Simulation, Antalya, Turkey, May 20-24, 2010.**Optimal control of PDEs with measures**,

Annual Meeting of the DMV, München, Germany, March 8-12, 2010.**A semismooth Newton method for optimal control problems in a measure space**,

14th Belgian-French-German Conference on Optimization, Leuven, Belgium, September 14-18, 2009.**Inverse problems with L1 data fitting**,

Applied Inverse Problems Conference, Wien, Austria, July 20-24, 2009.**A predual formulation for PDE constrained optimization with total variation regularization**,

Optimization with PDE Constraints (OPTPDE), Warsaw, Poland, December 11-13, 2008.**A direct method for the numerical time reversal of waves in a heterogeneous medium**,

6th International Congress on Industrial and Applied Mathematics (ICIAM), Zürich, Switzerland, July 16-20, 2007.**A non-standard numerical method for variational data assimilation for a convection-diffusion equation**,

Applied Inverse Problems Conference, Vancouver, Canada, June 25-29, 2007.**The quasi-reversibility method for thermoacoustic tomography in a heterogeneous medium**,

Applied Inverse Problems Conference, Vancouver, Canada, June 25-29, 2007.

## Kolloquia und Seminare

**Optimal control of nonsmooth partial differential equations**,

IFIP WG 7.2 Virtual Seminar, February 2, 2020.**Nonsmooth regularization of a coefficient inverse problem for the wave equation**,

Mathematical Colloquium, Universidade Federal de Santa Catarina, Florianópolis, Brasil, October 30, 2020 (online).**Convex relaxation of hybrid discrete-continuous control problems**,

Mathematisches Kolloquium, Heinrich-Heine-Universität Düsseldorf, December 13, 2019.**Multibang regularization of a coefficient inverse problem for the wave equation**,

Forschungsseminar Inverse Probleme und PDEs, TU Chemnitz, September 3, 2019.**Accelerated primal--dual methods for structured non-convex optimization**,

Computational and Applied Mathematics Seminar, Chalmers University of Technology, Göteborg, Sweden, August 28, 2019.**Generalized modes in Bayesian inverse problems**,

Forschungsseminar Mathematische Statistik, Humbold-Universität Berlin, February 9, 2019.**Nichtglatte Optimierung im Funktionenraum**,

Kolloquium Mathematik, Universität Paderborn, July 9, 2018.**Convex relaxation of hybrid discrete-continuous control problems**,

Universität Paderborn, March 13, 2018.**Convex regularization of discrete-valued inverse problems**,

Universiteit Twente, Enschede, Netherlands, September 27, 2017.**Convex relaxation of hybrid discrete-continuous control problems**,

Universität Bayreuth, June 16, 2017.**Convex relaxation of hybrid discrete-continuous control problems**,

Weierstraß-Institut für Angewandte Analysis und Stochastik, Berlin, March 29, 2017.**Stochastic inverse problems with impulsive noise**,

Karl-Franzens-Universität Graz, March 15, 2017.**Discrete regularization of parameter identification problems**,

Alpen-Adria-Universität Klagenfurt, November 16, 2016.**A primal-dual extragradient method for nonlinear inverse problems for PDEs**,

Karl-Franzens-Universität Graz, September 28, 2016.**Discrete regularization of parameter identification problems**,

University of Helsinki, August 25, 2016.**Discrete regularization of parameter identification problems**,

University of Tokyo, August 12, 2016.**Convex relaxation of hybrid discrete-continuous regularization**,

Fudan University, Shanghai, August 2, 2015.**Convex relaxation of hybrid discrete-continuous problems**,

Sandia National Laboratories, Albuquerque, March 23, 2015.**Sparse optimization of PDEs with application to light source placement**,

Kolloquium der FR Mathematik, Universität des Saarlandes, Saarbrücken, February 6, 2015.**Sparse optimization of PDEs with application to light source placement**,

Colloquium Nonlinear Science, Westfälische Wilhelms-Universität Münster, January 27, 2015.**Convex relaxation of hybrid binary-continuous penalties**,

Westfälische Wilhelms-Universität Münster, November 19, 2014.**Sparse optimization of PDEs with application to light source placement**,

University College London, October 10, 2014.**Wieviel Mathematik steckt im "Kernspin"?**,

WissensNacht Ruhr, Essen, October 2, 2014.**Nichtglatte Optimierung im Funktionenraum**,

Duisburger Arbeitskreis für Mathematik in Forschung und Praxis, May 27, 2014.**A convex analysis approach to hybrid binary-continuous optimal control problems**,

University of California, Riverside, May 23, 2014.**A convex analysis approach to hybrid binary-continuous optimal control problems**,

Cambridge University, April 28, 2014.**A convex analysis approach to hybrid binary-continuous optimal control problems with application to multi-bang controls**,

Institut für Mathematik, Alpen-Adria-Universität Klagenfurt, January 14, 2014.**Multi-bang control of elliptic equations**,

Zentrum Mathematik, Technische Universität München, December 17, 2013.**Parameter identification problems with non-Gaussian noise**,

Lothar Collatz Colloquium, Universität Hamburg, May 16, 2013.**Numerische Optimierung im Maßraum**,

Universität Bayreuth, April 17, 2013.**Numerische Optimierung im Maßraum**,

Humboldt-Universität zu Berlin, February 11, 2013.**Parameter identification problems with non-Gaussian noise**,

University of Tokyo, January 24, 2013.**Parabolic control problems in measure spaces**,

Julius-Maximilians-Universität Würzburg, June 5, 2012.**Parameteridentifizierung mit Impulsrauschen**,

Universität Duisburg-Essen, January 27, 2012.**Inverse problems with non-smooth noise models**,

Helmholtz Zentrum München, October 27, 2011.**A semi-smooth Newton method for nonlinear inverse problems with L1 data fitting**,

RICAM, Linz, February 18, 2011.**A primal-dual semi-smooth Newton method for nonlinear L1 data fitting**,

Institute of Computational Mathematics and Scientific/Engineering Computing, Chinese Academy of Sciences, Beijing, August 24, 2010.**PDE-constrained optimization with L1-type functionals**,

Institute of Computational Mathematics and Scientific/Engineering Computing, Chinese Academy of Sciences, Beijing, August 18, 2010.**PDE-constrained optimization with L1-type functionals**,

Universität Konstanz, April 14, 2010.**Inverse problems with L1 data fitting: A semismooth Newton method and automatic parameter choice**,

Johannes-Kepler Universität Linz, July 13, 2009.**Basic Principles of (P)MRI**,

Karl-Franzens-Universität Graz, December 3, 2008.

(very informal; animations missing; caution: ~7MB)**Time Reversal and Thermoacoustic Tomography**,

Georg-August-Universität Göttingen, October 30, 2007.**A direct method for the numerical time reversal of waves in a heterogeneous medium**,

Karl-Franzens-Universität Graz, May 2, 2007.**A direct method for the numerical time reversal of waves in a heterogeneous medium**,

RICAM, Linz, March 6, 2007.