B. S. Daya Sagar
Behara Seshadri Daya Sagar, also known as B. S. Daya Sagar is an Indian mathematical geoscientist specializing in mathematical morphology. He is a professor of computer science at the Indian Statistical Institute, Bangalore. He is known as a specialist in mathematical morphology, fractal geometry. chaos theory, and their applications in geophysics, geographical information science, and computational geography. The Indian Geophysical Union awarded him the Krishnan Medal in 2002. He is the first Asian to receive the Georges Matheron Lectureship in 2011. In 2018, he received the IAMG Certificate of Appreciation by the International Association for Mathematical Geosciences for his work on the
Handbook of Mathematical Geosciences.
Education
Sagar was educated at St. Anthony's School, Visakhapatnam, Government High School-Samalkota, and Government Arts College-Srikakulam, India. He graduated with BSc in 1987 from Shree Durga Prasad Saraf College of Arts and Applied Sciences, Sriramnagar, an affiliated college of Andhra University. Subsequently, he received MSc and PhD degrees from the Andhra University College of Engineering-Visakhapatnam, India, in 1991 and 1994 respectively. His PhD thesis is on 'Applications of Remote Sensing, Mathematical Morphology, and Fractals to Study Certain Surface Water Bodies'.Career
After receiving his doctorate, Sagar worked in Andhra University College of Engineering as a research associate of CSIR, and as a research scientist/principal investigator in the Scheme for Extramural Research for Young Scientists funded by Ministry of Science and Technology. From 1998–2001, he worked as a research scientist at the Centre for Remote Imaging Sensing and Processing of the National University of Singapore. He was appointed Associate Professor of Faculty of Engineering and Technology, Multimedia University, Malaysia in 2001 and was also a Deputy Chairman of the Centre for Applied Electromagnetics there. During 2007–13, he was an Associate Professor at the Indian Statistical Institute-Bangalore centre, and since 2009, he has been acting as founding head of SSIU, a unit established in 2009 as a constituent unit of its Computer and Communication Sciences Division. Since 2013, he has been a professor at the Indian Statistical Institute.Research
Sagar's research contributions span both basic and applied fields, and involves the fusion of computer simulations and modeling techniques in order to develop cogent models in discrete space to gain an understanding of dynamical behavior of complex terrestrial systems, such as water bodies, river networks, mountain objects, folds, dunes, landscapes, and rock porous media. He developed specific technologies and spatial algorithms for using data acquired at multiple spatial and temporal scales for developing cogent domain-specific models. His work employs concepts stemmed out of recent theories—such as mathematical morphology, fractals, chaos, and morphometrics—to develop spatial algorithms for pattern retrieval, pattern analysis, simulation and modeling, and reasoning and visualization of the spatial and temporal phenomena of terrestrial and GISci relevance. His studies show that there exist several open challenges that need to be addressed by mathematical geosciences community. One of such challenges is to understand the complexity in spatiotemporal behaviors of several terrestrial phenomena and processes via construction of process-specific attractors that may range from simple to strange.Professional
Sagar has been honored with the Georges Matheron Lectureship Award of International Association for Mathematical Geosciences for outstanding research ability in the field of spatial statistics or mathematical morphology. In 2002 he received Krishnan Medal of the Indian Geophysical Union. As recipient of this medal, Sagar was made IGU Fellow in 2011. In 1995, he received Dr. Balakrishna Memorial Award from the Regional Centre of Andhra Pradesh Akademi of Sciences. He is an elected Fellow of Royal Geographical Society, Fellow of Indian Geophysical Union, Senior Member of IEEE and was a member of New York Academy of Science during 1995–96. He is on the Editorial Boards of Discrete Dynamics of Nature and Society, and Computers & Geosciences. He has published 80+ papers in peer reviewed international journals, 3 books, and 7 edited Special-Theme issues for well known journals. He has been on Editorial Boards of Computers & Geosciences, Mathematical Geosciences, and Discrete Dynamics in Nature & Society.Award-2011 of International Association for Mathematical Geosciences from Qiuming Cheng in Salzburg, Austria on 7 September 2011
Professional activities
- Editor of Discrete Dynamics in Nature and Society: Multidisciplinary Research and Review Journal
- Editorial Board Member, Computers & Geosciences
- Editorial Board Member, Mathematical Geosciences
- Review Editor of Environmental Informatics-Frontiers
- Associate Editor of Image Analysis & Stereology
- Founding Chairman, Bangalore Section IEEE GRSS Chapter
Honors and awards
- Award of IAMG Certificate of Appreciation - 2018 from International Association for Mathematical Geosciences
- Georges Matheron Lectureship Award-2011 from International Association for Mathematical Geosciences '
- CURZONCO-SESHACHALAM LECTURES-5
- Krishnan Medal 2002 from Indian Geophysical Union
- Dr. Balakrishna Memorial Award 1995 from Regional Centre of Andhra Pradesh Akademi of Sciences
- Fellow, Indian Geophysical Union
- Fellow, Royal Geographical Society
Books
- B. S. Daya Sagar, Qiuming Cheng, and Frits Agterberg, Handbook of Mathematical Geosciences: Fifty Years of IAMG, Springer Publishers: Cham, p. 942, 2018.
- B. S. Daya Sagar, Mathematical Morphology in Geomorphology and GISci, CRC Press: Boca Raton, p. 546, 2013.
- B. S. Daya Sagar, Qualitative Models of Certain Discrete Natural Features of Drainage Environment, Allied Publishers: New Delhi, p. 231, 2005.
Edited Journal Special Issues
- B. S. Daya Sagar , Special Issue on "Applied Earth Observation and Remote Sensing in India", IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, v. 10, no. 12, 2017.
- B. S. Daya Sagar , Special Issue on 'Filtering and Segmentation with Mathematical Morphology' IEEE Journal of Selected Topics in Signal Processing, v. 6, no. 7, p. 737-886, 2012.
- B. S. Daya Sagar , Special Issue on 'Spatial Information Retrieval, Analysis, Reasoning and Modelling', International Journal of Remote Sensing, v. 31, no. 22, p. 5747-6032, 2010.
- B. S. Daya Sagar , Special Section on 'Surficial Mapping', IEEE Geoscience and Remote Sensing Letters. v. 2, no. 4, p. 375-408, 2005.
- B. S. Daya Sagar Special Issue on 'Fractals in Geophysics' Chaos Solitons & Fractals, v. 19, no. 2, p. 237-462, 2004.
- B. S. Daya Sagar , Special Issue on 'Quantitative Image Morphology' International Journal Pattern Recognition and Artificial Intelligence, v. 17, no. 2, p. 163-330, 2003.
- B. S. Daya Sagar : Special Issue 'In memory of the Late Professor SVLN Rao' Journal of Mathematical Geosciences, v. 33, no. 3, p. 245-396, 2001.
Selected Recent Journal Publications
- B. S. Daya Sagar, 2019, Variable-Specific classification of zones, pairs of zones, and clusters of a spatial system via modified gravity model, IEEE Transactions on Emerging Topics in Computing. v. 7, no. 2, p. 230-241.
- Aditya Challa, Sravan Danda, B. S. Daya Sagar, and Laurent Najman, 2018, Some Properties of Interpolations Using Mathematical Morphology, IEEE Transactions on Image Processing, v. 27, no. 4, p. 2038-2048.
- B. S. Daya Sagar and Lim Sin Liang, 2015, Morphing of Grayscale DEMs via Morphological Interpolations, IEEE Journal on Selected Topics on Applied Earth Observation and Remote Sensing, v. 8, no. 11, p. 5190-5198.
- B. S. Daya Sagar and Lim Sin Liang, 2015, Ranks for pairs of spatial fields via metric based on grayscale morphological distances, IEEE Transactions on Image Processing, v. 24, no. 3, p. 908-918.
- B. S. Daya Sagar, 2014, Cartograms via mathematical morphology, Information Visualization, v. 13, no. 1, p. 42-58.
- B. S. Daya Sagar, 2010, Visualization of spatiotemporal behavior of discrete maps via generation of recursive median elements, IEEE Transactions on Pattern Analysis and Machine Intelligence, v. 32, no. 2, p. 378-384.
- Lim Sin Liang, and B. S. Daya Sagar, 2008, Cloud field segmentation via multiscale convexity analysis, Journal of Geophysical Research-Atmospheres, v. 113, D13208.
- Alan W. C. Tan, M. V. C. Rao, and B. S. Daya Sagar, 2007, Robust signal subspace speech classifier, IEEE Signal Processing Letters, v. 14, no. 11, p. 844-847.
- B. S. Daya Sagar, 2007, Universal scaling laws in surface water bodies and their zones of influence, Water Resources Research, v. 43, no. 2, W02416.
- Alan W. C. Tan, M. V. C. Rao, and B. S. Daya Sagar, 2007, A discriminative signal subspace speech classifier, IEEE Signal Processing Letters, v. 14, no. 2, p. 133-136.
- Lea Tien Tay, B. S. Daya Sagar, and Chuah Hein Teik, 2006, Allometric relationships between travel-time channel networks, convex hulls, and convexity measures, Water Resources Research, v. 42, no. 6,W06502.
- Lea Tien Tay, B. S. Daya Sagar, and Chuah Hein Teik, 2005, Analysis of geophysical networks derived from multiscale digital elevation models: a morphological approach, I.E.E.E Geoscience and Remote Sensing Letters. v. 2, no. 4, p. 399-403.
- L. Chockalingam and B. S. Daya Sagar, 2005, Morphometry of network and non-network space of basins, Journal of Geophysical Research-Solid Earth, v. 110, B08203.
- B. S. Daya Sagar, 2005, Discrete simulations of spatio-temporal dynamics of small water bodies under varied streamflow discharges, Nonlinear Processes in Geophysics, v. 12, p. 31-40.
- B. S. Daya Sagar and L. Chockalingam, 2004, Fractal dimension of non-network space of a catchment basin, Geophysical Research Letters, v. 31, no.12, L12502.
- B. S. Daya Sagar and Tay Lea Tien, Allometric power-law relationships in a Hortinian fractal digital elevation model, Geophysical Research Letters, v. 31, no. 6, L06501.