Associate Professor
Department of Physics and Mathematics
Via Valleggio 11, 22100 Como
Tel. +39 (0)31 2386370
Fax: +39 (0)31 2386209
E-mail: stefano.serrac@uninsubria.it

Date of Birth: August 2, 1967.

Degrees: 1990: M.Sc. in Computer Science, University of Pisa; 1996: Ph.D. in Computational and Applied Math., University of Milan.

Positions held: Temporary Professor of Calculus (University ``Calabria''): 1995-1996; Assistant Professor of Numerical Analysis (University of Florence): 1996-2000; Associate Professor of Numerical Analysis (University of Insubria): 2000-present. November 2004: elected (“Idoneita`’’) as Full Professor in Numerical Mathematics.

Visiting activity:
June 1998: Chinese University of Hong Kong (R. Chan);
January 2001: Indian Statistical Institute of New Delhi (R. Bhatia);
February 2001: Chinese University of Hong Kong (R. Chan).
February 2002: USTL of Lille (B. Beckermann).
June 2002: Chinese University of Hong Kong (R. Chan).
July 2002: Institute of Numerical Analysis - Russian Academy of Sciences Moscow (E. Tyrtyshnikov).
January 2003: University of Ioannina (D. Noutsos).

February 2003: SCCM center - Stanford University (G. Golub).

December 2003: Institute Mathematical Sciences - National University of Singapore (L. Shen).

February 2004: Uppsala University (S. Holmgren).

May 2004: Ljubljana University (M. Hladnik).

November 2004: University of Ioannina (D. Noutsos).
March-May 2005: Uppsala University (S. Holmgren).

Numerical Linear Algebra (application to PDE problems): multigrid methods, preconditioning etc.,

(Structured) Matrix Theory,

Asymptotic Linear Algebra (application to the spectral analysis of PDE problems),

Approximation Theory,

Positive Operators,

Image Restoration and Signal Processing (Inverse Problems).

Attending and Organization of Conferences: He has attended more than 50 international conferences and more than 20 times as invited speaker. He was part of the of Program and Scientific Committee of the Second Workshop on Numerical Analysis and Applications (Rousse (Bulgaria), June 11--15, 2000) where he organized (with G. Heinig) a symposium on ``Recent Advances on Structured Matrices and Applications''. He organized (with D. Bini) the special session on ``Structured Matrices in Imaging'' for the conference Applied Inverse Problems: Theoretical and Computational Aspects (Montecatini (Italy), June 18--22, 2001). Co-Chair of the conference SPIE: Advanced Signal Processing Algorithms, Architectures and Implementations XIII (S. Diego - California (USA), August 3--8, 2003) in which he organized a session with the title ``Structured Matrices in Signal Processing/Imaging''. Member of the International Program Committee for the conference Structured numerical linear algebra problems: algorithms and applications} (Cortona (Italy), September 19--24, 2004). Member of the Organizing Committee for the conference International Conference on Matrix Methods and Operator Equations (Moscow (Russia), June 20--25, 2005).

Organization of Scientific Projects: He has been involved in several national and international scientific projects on Structured Numerical Linear Algebra, Numerical Linear Algebra and Scientific Computing. Among them he was Director of a GNCS – INDAM (National Institute on Mathematics) project on Preconditioning for indefinite and non symmetric systems arising in certain differential and integral equations, of a MURST (Ministery of Research) project on Multigrid and Wavelets algorithms for image restoration problems with M. Tasche (Rostock), and of several Projects with R. Chan (Hong Kong - China), D. Noutsos (Ioannina - Greece).

He is part of the Seminar Board of the International Seminar on Matrix Methods and Operator Equations (see www.matrices\backslash\backslashnarod.ru) headed by E. Tyrtyshnikov (Academy of Sciences of Moscow).

He is a member of the Staff of the Doctorate Program of Milano (Computational Mathematics) and of Como - Insubria (Physics).

1995-96: Calculus (in Italian), Science Faculty, Università della Calabria - Arcavacata di Rende (Cosenza), Approximation Theory (in Italian), Science Faculty, University of Firenze.

1996-97: System Theory, Mathematical Methods for Biology (in Italian), Science Faculty, University of Firenze.

1997-98 and 1998-99: Mathematical Methods for Biology, Algorithms and Data Structures II (in Italian), Science Faculty, University of Firenze

1999-2000: Mathematical Methods for Biology, Numerical methods for Signals and Images (in Italian), Science Faculty, University of Firenze, Numerical methods and Programming (in Italian), Engineering Faculty, University of Siena.

2000-01 and 2001-02: Numerical Analysis I, Numerical Analysis II (in Italian), School of Sciences,Como.

2002-03 and 2003-2004: Numerical Analysis I, Numerical Analysis II}, Numerical Analysis III (in Italian), School of Sciences- Como.

2004-05: Numerical Analysis I, Numerical Analysis II, Approximation Theory I, Approximation Theory II (in Italian), School of Sciences at the University of Insubria - Como.

Teaching activity in English (Master, Phd level)

2003-2004 and 2004-05: Numerical Linear Algebra for graduate students, Master and PhD School FMB Uppsala University (Sweden), PhD School in Applied Mathematics Milano University, PhD School in Mathematics Genova University, in English.

Other qualifications: He is one of the member committee for the E-Learning project of the University of Insubria and he is the head of the Mathematicians of the Science Faculty of Como (University of Insubria).

1 ``Preconditioning strategies for asymptotically ill-conditioned block Toeplitz systems'', BIT, Vol. 34, N.4 (1994), pp. 579--594.

2 ``Multigrid methods for symmetric positive definite block Toeplitz matrices with nonnegative generating functions'', SIAM Journal on Scientific Computing, Vol. 17, N. 5 (1996), pp. 1068--1081. With G. Fiorentino.

3 ``Preconditioning strategies for Hermitian Toeplitz systems with nondefinite generating functions'', SIAM Journal on Matrix Analysis and Applications, Vol. 17, N. 4 (1996), pp. 1007--1019.

4 ``Asymptotic expansion and extrapolation for Bernstein polynomials and some applications'', BIT Vol. 36, N. 4 (1996), pp. 676--687. With F. Costabile e M.I. Gualtieri.

5 ``Optimal, quasi-optimal and superlinear preconditioners for asymptotically ill-conditioned positive definite Toeplitz systems'', Mathematics of Computation} Vol. 66, N. 218 (1997), pp. 651--665.

6 ``On the extreme eigenvalues of Hermitian (block) Toeplitz matrices'', Linear Algebra and its Applications, Vol. 270 (1998), pp. 109--129.

7 ``An ergodic theorem for classes of preconditioned matrices'', Linear Algebra and its Applications, Vol. 282 (1998), pp. 161--183.

8 ``Asymptotic results on the spectra of block Toeplitz preconditioned matrices'', SIAM Journal on Matrix Analysis and Applications, Vol. 20, N.1 (1998), pp. 31--44.

9 ``Toeplitz preconditioners constructed from linear approximation processes'', SIAM Journal on Matrix Analysis and Applications, Vol. 20, N.2 (1998), pp. 446--465.

10 ``The rate of convergence of Toeplitz based PCG methods for second order nonlinear boundary value problems'', Numerische Mathematik}, Vol. 81, N.3 (1999), pp. 461--495.

11 ``A unifying approach to abstract matrix algebra preconditioning'', Numerische Mathematik, Vol. 82, N.1 (1999), pp. 57--90. With F. Di Benedetto.

12 ``A Korovkin-type Theory for finite Toeplitz operators via matrix algebras'', Numerische Mathematik, Vol. 82, N.1 (1999), pp. 117--142.

13 ``Spectral and computational analysis of block Toeplitz matrices having nonnegative definite matrix-valued generating functions'', BIT, Vol. 39, N.1 (1999), pp. 152--175.

14 How to choose the best iterative strategy for symmetric Toeplitz systems'', SIAM Journal on Numerical Analysis}, Vol. 36, N.4 (1999), pp. 1078--1103.

15 ``Analytical analysis of Gavrilov-Guckenheimer bifurcation unfolding in the case of a PI controlled CSTR'', SIAM Journal on Applied Mathematics, Vol. 59, N.5 (1999), pp. 1716--1744. With C. Tablino Possio.

16 ``Spectral and structural analysis of high precision Finite Difference matrices for Elliptic Operators'', Linear Algebra and its Applications}, Vol. 293 (1999), pp. 85--131. With C. Tablino Possio.

17 ``Extreme singular values and eigenvalues of non Hermitian Toeplitz matrices'', Journal of Computational and Applied Mathematics, Vol. 108, N.1-2 (1999), pp. 113--130. With P. Tilli.

18 ``A Korovkin based approximation of multilevel Toeplitz matrices (with rectangular unstructured blocks) via multilevel trigonometric matrix spaces'', SIAM Journal on Numerical Analysis, Vol. 36, N.6 (1999), pp. 1831--1857.

19 ``Any circulant-like preconditioner for multilevel matrices

20 is not superlinear'', SIAM Journal on Matrix Analysis and Applications, Vol. 21, N.2 (1999), pp. 431--439. With E. Tyrtyshnikov.

21 ``How bad can positive definite Toeplitz matrices be?'' Numerical Functional Analysis and Optimization, Vol. 21, N.1-2 (2000), pp. 255--261).

22 ``Locally X matrices, spectral distributions, preconditioning and applications'', SIAM Journal on Matrix Analysis and Applications, Vol.

21, N. 4 (2000), pp. 1354--1388.

23 ``Korovkin tests, approximation, and ergodic theory'', Mathematics of Computation, Vol. 69 (2000), pp. 1533--1558.

24 ``A note on the asymptotic spectra of finite difference discretizations of second order elliptic Partial Differential Equations'', Asian Journal of Mathematics, Vol. 4 (2000), pp. 499--514.

25 ``Spectral analysis of (sequences of) graph matrices'', SIAM Journal on Matrix Analysis and Applications, Vol. 23, N.2 (2001), pp. 339--348. With A. Frangioni.

26 ``Positive representation formulas for finite difference discretizations of (elliptic) second order PDEs'', Contemporary Mathematics} Vol. 281 (2001), pp. 295--318. With C. Tablino Possio.

27 ``Asymptotic zero distribution of orthogonal polynomials with discontinuously varying recurrence coefficients'', Journal of Approximation Theory, Vol 113 (2001), pp. 142--155. With A. Kuijlaars.

28 ``Convergence analysis of Two-Grid methods for elliptic Toeplitz and PDEs matrix-sequences'', Numerische Mathematik, Vol 92, N.3 (2002), pp. 433—465.

29 ``Generalized Locally Toeplitz sequences: spectral analysis and applications to discretized Partial Differential equations'', Linear Algebra and its Applications, Vol. 366-1 (2003), pp. 371--402.

30 ``Fat diagonals and Fourier analysis'', SIAM Journal on Matrix Analysis and Applications, Vol. 24-4 (2003), pp. 1060--1070. With M. Hladnik and J. Holbrook.

31 ``A note on anti-reflective boundary conditions and fast deblurring models''}, SIAM Journal on Scientific Computing, Vol. 25-4 (2003), pp. 1307--1325.

32 ``The spectra of preconditioned Toeplitz matrix sequences can have gaps'', SIAM Journal on Matrix Analysis and Applications, Vol. 25-4 (2004), pp. 930--946. With T. Huckle.

33 ``Preconditioning strategies for Hermitian indefinite Toeplitz linear systems'', SIAM Journal on Scientific Computing, Vol. 25-5 (2004), pp. 1633--1654. With T. Huckle and C. Tablino Possio.

34 ``V-cycle optimal convergence for certain (multilevel) structured linear systems'', SIAM Journal on Matrix Analysis and Applications, Vol. 26-1 (2004), pp. 186--214. With A. Arico' and M. Donatelli.

35 ``Matrix algebra preconditioners for multilevel Toeplitz systems do not insure optimal convergence rate'', Theoretical Computer Science, Vol. 315 (2004), pp 557--579. With D. Noutsos and P. Vassalos.

36 ``Anti-reflective boundary conditions and re-blurring'', Inverse Problems, Vol. 21 (2005), pp. 169--182. With M. Donatelli.

37 ``Preconditioned HSS methods for the solution of non-Hermitian positive definite linear systems and applications to the discrete convection-diffusion equation'', Numerische Mathematik, Vol. 99, N.3 (2005), pp. 441--484. With D. Bertaccini, G. Golub, and C. Tablino Possio.

38 ``PCG regularization of inverse problems arising in image restoration'', SIAM Journal on Scientific Computing}, Vol. 26, N.3 (2005), pp. 1012--1035. With F. Di Benedetto and C. Estatico.

39 ``How to deduce a proper eigenvalue cluster from a proper singular value cluster in the non-normal case'', SIAM Journal on Matrix Analysis and Applications, Vol. 27, N.1 (2005), pp. 82-86. With D. Bertaccini and G. Golub.

40 ``Jordan canonical form of the Google matrix: a potential contribution to the PageRank computation'', SIAM Journal on Matrix Analysis and Applications, Vol. 27, N.2 (2005), pp. 305-312.