Department of Mathematics and Statistics

Ratnasingham Shivaji
H. Barton Excellence Professor
Department Head


Office: Petty 118
Phone: 334-5836
Email address:
Personal web page:
Starting year at UNCG: 2011
Office hours: TR 2:00 p.m. - 3:30 p.m. and by appointment


Ph.D. in Mathematics, Heriot-Watt University (1981)


Fall, 2018
  • MAT 390-01 LEC (Ordinary Differential Equatns), TR 11:00-12:15, Petty Building 217
  • MAT 709-01 IND (Topics in Computational Math), MW 4:00-5:15, Petty Building 313
  • MAT 593-01 IND (Directed Study in Mathematics)
  • MAT 790-03 IND (Directed Doctoral Research)
  • MAT 493-01 IND (Honors Work)

Research Interests

Applied Math, Mathematical Biology
Current Students: Amila Muthunayake, Nalin Fonseka, Mohan Mallick (IIT-India)
Descendants: Byungjae Son, Quinn Morris

Selected Recent Publications

  • On radial solutions for singular combined superlinear elliptic systems on annular domains, D. D. Hai and R. Shivaji, J. Math. Anal. Appl., Vol. 446, 2017, No. 1, pp. 103-114.
  • Stability analysis for positive solutions for classes of semilinear elliptic boundary value problems with nonlinear boundary conditions, Jerome Goddard and R. Shivaji, accepted for publication, Proc. Royal Soc. Edin.
  • A uniqueness result for a semipositone p-Laplacian problem on the exterior of a ball, R. Shivaji, Imbo Sim, and Byungjae Son, accepted for publication, J. Math.Anal. Appl.
  • Multiple positive solutions for a class of variational systems, Alfonso Castro, David Costa, and R. Shivaji, accepted for publication, Topological Methods in Nonlinear Analysis.
  • Positive radial solutions for a class of singular superlinear problems on the exterior of a ball with nonlinear boundary conditions, D. D. Hai and R. Shivaji, accepted for publication, J. Math. Anal. Appl.

Brief Bio

Ratnasingham Shivaji joined the University of North Carolina at Greensboro (UNCG) as Head in July 2011. Since January 2012, he is also serving as H. Barton Excellence Professor. Prior to joining UNCG, he served for twenty-six years at Mississippi State University (MSU), where he was honored as a W.L. Giles Distinguished Professor. He received his Ph.D in Mathematics from Heriot-Watt University in Edinburgh, Scotland in 1981 and his B.S (first class honors) from the University of Sri Lanka in 1977. Shivaji's area of specialization is partial differential equations, and in particular, nonlinear elliptic boundary value problems. His research work has applications in combustion theory, chemical reactor theory, and population dynamics, and has been funded by the National Science Foundation and the Simon's Foundation. Currently, he is serving as the PI on an NSF Math Ecology grant. To date, he has authored one hundred forty-one research papers. He is a member of the Editorial Board of several mathematics journals.To date, he has directed one postdoctoral student, sixteen Ph.D. students (13 graduates, 3 current), fifteen M.S. students (14 graduates, 1 current), and twenty-two undergraduate research students (19 graduates, 3 current).