Visiting Researchers, University of Rennes, France, June, 2024.
Visiting Researchers, University of Nantes, France, Nov., 2023.
Visiting Professor, Technical University of Czestochowa, Poland, June, 2022.
Visiting Scientist, University of Warsaw, June, 2019.
Senior Associate, International Center of Theoretical Physics (ICTP), Italy, August-September, 2018
Visiting Professor, Middle East Technological University (METU), July, 2017.
Visiting Scientist, Institute polytechnique de Grenoble (Grenoble INP), France, October, 2016.
Visiting Professor, Corvinus University Budapest, Hungary, June, 2016.
Visiting Professor, University of Padova, Italy, May, 2016.
Visiting Professor, University of Ljubljana, Slovenia, Sept-Oct, 2015.
Visiting Professor, Corvinus University Budapest, Hungary, July 2015.
Visiting Professor, University of Padova, Italy, Sept., 2014.
Senior Associate, International Center of Theoretical Physics (ICTP), Italy, May, 2014
Visiting Professor, Interdisciplinary Center for Mathematical and Computational Modelling (ICM), University of Warsaw, August 2013.
Visiting Professor, Institute polytechnique de Grenoble (Grenoble INP), France, May-June, 2013.
Alexander von Humboldt Visiting Researcher, German Cancer Research Center (DKFZ), Heidelberg, Germany, April 2012 to June 2012.
Alexander von Humboldt Visiting Researcher, German Cancer Research Center (DKFZ), Heidelberg, Germany, April 2011 to June 2011.
Visiting Scientist, Max Plank Institute (MPI), Saarbrucken, Germany, April 2011 to May 2011.
Visiting Professor, Institut polytechnique de Grenoble (Grenoble INP), France, September 2010..
Alexander von Humboldt Visiting Researcher, German Cancer Research Center (DKFZ), Heidelberg, Germany, May 2010 to July 2010.
Visiting Professor, Department of Mathematics and Computer Science, University of Heidelberg, Germany, September 2009 to November 2009.
Visiting Professor, Department of Sociology and Communication, Rome University, Italy, May 2008 to June 2008.
Visiting Professor, Department of Automation, Bioinformatics Division, Tsinghua University, China, July 2007 to August 2007.
Visiting Scientist, Fraunhofer Institute for Autonome Intelligente Systems, St. Augustin, Germany, October 2005 to November 2005.
Visiting Research Associate Professor, Department of Computer Science and Electrical Engineering University of Maryland Baltimore County, Baltimore, USA, June 2004 to July 2004 ( worked under a NASA funded project).
Guest faculty, Department of Computer Science and Engineering, University of Texas at Arlington, Texas, USA, April 2001 to July 2001.
Post doctoral (BOYSCAST) research fellow, Department of Computer Science and Engineering, University of Texas at Arlington, Texas, USA, March 2001 to October 2001.
Research Assistant, School of Geomatic Engineering, University of New South Wales, Sydney, Australia, May 1999 to September 1999.
Scientist, Los Alamos National Laboratory and consultant to Adaptive System and Application (CASA), Los Alamos, New Mexico, USA, June 1997 to September 1997.