Christos Kravvaritis

Address:

TU München

Institut für Informatik

Boltzmannstr. 3

85748 Garching b. München

Office:

MI 02.05.036

Email:

christos.kravvaritis@in.tum.de

Phone:

(089) 289 18 615

Fax:

(089) 289 18 607

Personal Homepage:

http://ckravv.googlepages.com

Office Hours

By arrangement

---

Forschungsgebiete (Research Area)

• Numerische Lineare Algebra
• Multigridverfahren
• Strukturierte Matrizen (Hadamard, weighing, compound)
• Determinanten
• Numerische Methoden für ODEs und PDEs
• Codierungstheorie

---

List of Publications

Refereed Publications

C. Kravvaritis and M. Mitrouli, The growth factor of a Hadamard matrix of order 16 is 16, 2009, Numer. Linear Algebra Appl., to appear.

C. Kravvaritis and M. Mitrouli, A technique for computing minors of binary Hadamard matrices and application to the Growth Problem, Electron. Trans. Numer. Anal., 31 (2008), 49-67.

J. Geiser and C. Kravvaritis, Overlapping operator splitting methods and applications in stiff differential equations, Neural Parallel Sci. Comput., 16(2008), 189-200.

C. Kravvaritis and M. Mitrouli, Compound matrices: properties, numerical issues and analytical computations, Numer. Algorithms, (2008), to appear.

J. Geiser and C. Kravvaritis, A Domain Decomposition Method based on the Iterative Operator Splitting Method, Appl. Numer. Math., (2008), in press.

C. Kravvaritis and M. Mitrouli, An Algorithm to Find Values of Minors of Hadamard Matrices, Bull. Greek Math. Soc., 54 (2007), 221-238.

C. Kravvaritis and M. Mitrouli, Evaluation of Minors associated to weighing matrices, Linear Algebra Appl., 426 (2007), 774-809.

C. Kravvaritis, M. Mitrouli and J. Seberry, On the Pivot Structure for the Weighing Matrix W(12,11), Linear Multilinear Algebra, 55:5 (2007), 471-:490.

C. Kravvaritis and M. Mitrouli, Determinant Evaluations for Weighing Matrices, Int. J. Pure Appl. Math., 34:2 (2007), 163-176.

J. Geiser and C. Kravvaritis, Weighted Iterative Operator Splitting Methods and Applications, Lecture Notes in Comput. Sci., 4310 (2007), 48-55.

S. Georgiou and C. Kravvaritis, New Good Quasi-Cyclic Codes over GF(3), Int. J. Algebra, 1:1 (2007), 11-24.

C. Kravvaritis, M. Mitrouli and J. Seberry, Counting Techniques Specifying the Existence of Submatrices in Weighing Matrices, Lecture Notes in Comput. Sci., 3718 (2005), 294-305.

C. Kravvaritis, E. Lappas and M. Mitrouli, An algorithm to find values of minors of weighing matrices, Lecture Notes in Comput. Sci., 3401 (2005), 375-382.

C. Kravvaritis, M. Mitrouli and J. Seberry, On the growth problem for skew and symmetric conference matrices, Linear Algebra Appl., 403 (2005), 183-206.

Papers in refereed conference proceedings

C. Kravvaritis, Analytical Formulas for Minors of Orthogonal Matrices and an Application, «ICTCAM ’07 – International Conference on Trends in Computational and Applied Mathematics», 237-240, (Bucharest – Romania, June 2007).

C. Kravvaritis, Growth Factors for Orthogonal (0,1,-1) Matrices, «Hellenic Conference on Mathematical Education», 531-541, (Kozani – Greece, November 2007).

Submitted papers

J. Geiser and C. Kravvaritis, An Operator Splitting method with embedded Newton method. (J. Comput. Appl. Math.) - February 2008

J. Geiser and C. Kravvaritis, Extended Iterative Operator Splitting methods for stiff problems and applications. (J. Comput. Appl. Math.) - July 2008

C. Kravvaritis and M. Mitrouli, On some numerical properties of Hadamard matrices. (Appl. Numer. Math.) - December 2008

C. Kravvaritis, Determinant Evaluations for Binary Circulant Matrices. (Electron. J. Linear Algebra) - January 2009

Theses

Christos Kravvaritis, Weighing matrices and their contribution to the study of the growth problem, Master Thesis, University of Athens, 2004.

Christos Kravvaritis, A determinant computations framework for Weighing matrices and application to the growth problem, PhD Thesis, University of Athens, 2008.

---

Selected Publications

A technique for computing minors of binary Hadamard matrices and apllication to the Growth Problem, Electron. Trans. Numer. Anal., 31 (2008) 49-67, joint work with M. Mitrouli.
Compound matrices: properties, numerical issues and analytical computations, Numer. Algorithms, 2009, to appear, joint work with M. Mitrouli.
A Domain Decomposition Method based on the Iterative Operator Splitting Method, Appl. Numer. Math., 2008, to appear joint work with J. Geiser.
Evaluation of Minors associated to weighing matrices, Linear Algebra Appl., 426 (2007) 774-809, joint work with M. Mitrouli.
On the Pivot Structure for the Weighing Matrix W(12,11), Linear Multrilinear Algebra, 34 (2007) 163-176, joint work with M. Mitrouli and J. Seberry.
On the growth problem for skew and symmetric conference matrices, Linear Algebra Appl., 403 (2005) 183-206, joint work with M. Mitrouli and J. Seberry.

---