(Raimondas CIEGIS)

  Raimondas Ciegis was born on the 18th October 1958 in Kaunas, Lithuania. He graduated from Kaunas 7-th Secondary School in 1977 and from Vilnius University Faculty of Mathematics in 1982. R.Ciegis received a doctor's degree in Mathematical Sciences in 1985 from the Institute of Mathematics, Minsk, Belarussia and a degree of Doctor Hab. in mathematics in 1993 from the Institute of Mathematics, Vilnius, Lithuania.

R.Ciegis received a degree of an associate professor in 1993 and a degree of professor in 1994 from Vytautas Magnus University. He is a Senior Researcher at the Numerical Methods Department of the Institute Mathematics and Informatics, and a professor of mathematics at Vilnius University. He is a head of Mathematical modelling Department of Vilnius Gediminas Technical University. His six doctoral students defended their dissertations and obtained a degree of PhD of Mathematical Sciences in 1990 - 1999. Now five doctoral students are preparing their doctoral thesis.

Scientific interests of R.Ciegis involve numerical methods for solving ODE and PDE, and mathematical modelling in physics, technology, biology. He investigate finite difference schemes and iterative methods for nonlinear nonstationary PDE and problems with nonclassical (nonlocal) boundary conditions. His recent scientific interests deal with the stability of differences schemes with respect to boundary and initial conditions. These problems include the investigation of the accuracy of LOD schemes, the analysis of the efficiency of decomposition methods, including the local refinement algorithms. Now he is interested in parallel numerical methods and mathematical modelling of nonlinear optics, ecology and engineering problems.

He organizes international conferences "Mathematical modelling and analysis" (see http://www.aldona.mii.lt/mma/).

The results are publicated in 135 papers and two textbooks. In 1988 R.Ciegis received the Lithuanian State premium for young scientists, in 1996 he received the Lithuanian State premium.

Main publications:

1. R. Ciegis, On the convergence rate of some iterative methods of variational type . Mathematical modelling, 1997, V.9, No. 4, 115-125.
2. R. Ciegis, A. Zemitis, The mathematical simulation of the liquid trasport in multilayered nonwoven. Report Berichte der Arbeitsgruppe Technomathematik, Kaiserslautern University, Nr. 184, 1997, (also Mathematical modelling and complex analysis, 319, Ed. R. Ciegis, Proc. 2nd Intern. Conf. on Mathematical modelling and complex analysis - 97, Vilnius, Technika, 1997).
3. K. Kiskis, R. Ciegis, On the stability of additive difference schemes with respect to boundary conditions. Liet. matem. rink., 1997, 37(4), P. 483-494.
4. R. Ciegis. On the accuracy of a posteriori estimates for finite element schemes, Pitman Research Notes in Mathematical Series, 1997, 375 Integral methods in science and engineering, 2: approximation methods (C.Constanda, J. Saranen, S.Seikkala, Editors), pp. 74-78.
5. R. Ciegis, R. Sablinskas, J. Wasniewski, Numerical integration on distributed-memory parallel system. Lecture Notes in Computer Science, Vol. 1332, Recent advances in Parallel Virtual Machine and Message Passing Interface, Proc.: 4th European PVMI MPI User's Group Meeting, Cracow, Poland, November 1997, Springer, 1997, 329-336.
6. R. Ciegis, R. Sablinskas, J. Wasniewski, Numerical integration on distributed-memory parallel system. Informatica, 1998, 9(2), 123-140 (also Report UNIC-97-01, Denmark, 1997).
7. R. Ciegis, O. Stikoniene, Semiimplicit schemes for nonlinear Schodinger type equations. In: Proc. of the 6th Intern. Conference NSEC-6, Palanga, Lithuania, 1997, Navier-Stokes Equations and Related Nonlinear Problems, H. Amann, G.P. Galdi, K. Pileckas and V.A. Solonikov (Eds.), VSP/TEV, Utrect/Vilnius, 1998, 53-68.
8. Raim Ciegis, Rem. Ciegis, A. Zemitis, Parallel numerical methods for the elliptic-parabolic problem. In: Progress in Industrial Mathematics at ECMI98, L. Arkeryd, J. Bergh, P. Brenner and R. Pettersson (Eds.), B.G. Teubner, Stuttgart, Leipzig, 1999, 206-213.
9. R. Ciegis, R. Sablinskas, Hyper-rectangle distribution algorithm for parallel adative numerical integration, Informatica, 1999, 10(2), 161-170.
10. R. Ciegis, O. Stikoniene, Explicit second-order accurate schemes for the nonlinear Schrodinger equation, Liet. matem. rink., 1999, 39(1), 24-39.
11. R. Ciegis, O. Stikoniene, Stability analysis of some two-dimensional finite-difference schemes, Proceedings of the Estonian Academy of Sciences, Physics-Mathematics, 1999, 48(2), 111-122.
12. R. Ciegis, R. Sablinskas, J. Wasniewski, Hyper-rectangle distribution algorithm for parallel multidimensional numerical integration, Lecture Notes in Computer Science, Vol. 1697, Recent advances in PVM and MPI, 6th European PVM/MPI user's group meeting, Barselona, Spain, J. Dongarra, E. Luque and T. Margalef (Eds.), 1999, 113-118.

Contact information:
Phone: +(370 2) 729 415
Fax: +(370 2) 729 209
E-mail: rc@fm.vtu.lt