Communications to Conferences

. Invited lecture: On the forward-backward methods in data processing, IV - One Day Workshop on Applied Mathematics 2022, Bari, 31 May, 2022

. V. Ruggiero: Ritz-like values in steplength selections for stochastic gradient methods, PRIMO Meeting, 2 October, 2020

. V. Ruggiero: Acceleration techniques in the Forward-Backward methods for the reconstruction of data corrupted by Poisson noise, UMI, Pavia, September, 2-7, 2019.

· V. Ruggiero: A general framework for inertial variable-metric forward-backward algorithm, INDAM Intensive Period, Computational Methods for Inverse Problems in Imaging, Como, June, 12, 2018.

.L. Zanni, V. Ruggiero: First-order optimization methods for imaging problems, Int. Conf. on Optimization and Decision Science, Sorrento, September, 4-7, 2017.

· Invited lecture: Image reconstruction with Poisson data: numerical methods and applications, Torino, 1 December, 2016.

· A. Benfenati, S. Bonettini, V. Ruggiero: Scaling Techniques for $\epsilon$--subgradients methods, SIMAI 2016, Milan, September, 13-16, 2016.

· F. Porta, S. Bonettini, V. Ruggiero: A variable metric proximal-gradient method with extrapolation, SIMAI 2016, Milan, September, 13-16, 2016.

· M. Miranda Jr., M. Zanetti, V. Ruggiero: A numerical approach to the minimization of an elliptic approximation of the Blake-Zisserman functional, Joint Meeting Brazil – Italy, Rio de Janeiro, 29 August - 2 September, 2016.

· V. L. Coli, V. Ruggiero, L. Zanni: Scaled first-order methods for a class of large-scale constrained least squares problems, Numerical Computations: Theory and Algorithms, International Workshop, Pizzo Calabro (Italy), June 19-25, 2016.

· R. Zanella, M. Zanetti, V. Ruggiero: A parallel approach for image segmentation by numerical minimization of a second-order functional, Numerical Computations: Theory and Algorithms, International Workshop, Pizzo Calabro (Italy), June 19-25, 2016.

· G. Toraldo, D. Di Serafino, V. Ruggiero, L. Zanni: A Note on Spectral Properties of Some Gradient Methods, Numerical Computations: Theory and Algorithms, International Workshop, Pizzo Calabro (Italy), June 19-25, 2016.

· Invited lecture: V. Ruggiero, Scaling techniques for є-subgradient projection methods, Genova Machine Learning & Robotics Seminar Series, 11 March 2015

· A. Benfenati, V. Ruggiero, Inexact Bregman Regularization for Astronomical Images Corrupted by Poisson Noise, SIMAI 2014, Taormina, July 2014

· A. Benfenati, V. Ruggiero, Image restoration from Poisson data by an Inexact Bregman Iteration Scheme, Numerical Computation: Theory and Applications, Falerna, 17-23 June 2013

· A. Benfenati, V. Ruggiero, Inexact Bregman Iteration with applications to Poisson data reconstruction, 11th EUROPT Workshop on Advances in Continuous Optimization, Firenze, June 6-28, 2013

· S. Bonettini, V. Ruggiero, Primal--dual hybrid gradient algorithms for image restoration, SIMAI 2012, Torino, June 2012

· S. Bonettini, V. Ruggiero, An alternating extragradient method for total variation based image restoration for Poisson data, AFG’11, Toulouse, September, 19-23 2011.

· S. Bonettini, V. Ruggiero, Un metodo extragradiente per la ricostruzione di immagini mediante regolarizzazione con la funzione di Variazione Totale, XIX Congresso dell’UMI, Bologna, September, 12-17 2011.

· S. Bonettini, V. Ruggiero, On the uniqueness of the solution of image reconstruction problems with Poisson data, ICNAAM 2010: International Conference of Numerical Analysis and Applied Mathematics 2010, Rhodes, September, 19-25, 2010.

· S. Bonettini, V. Ruggiero, F. Tinti, On the solution of indefinite systems arising in nonlinear optimization, SIMAI 2006, Baia Samuele, May, 25, 2006.

· S. Bonettini, V. Ruggiero, F. Tinti, A preconditioner for solving large scale variational inequality problems, SIMAI 2006, Baia Samuele, May, 25, 2006.

· Invited lecture: V. Ruggiero, Ottimizzazione e Calcolo Parallelo, Workshop in honour of Alfonso Laratta, October, 13, Modena, 2004.

· S. Bonettini, E. Galligani, V. Ruggiero, Interior point method as inexact Newton method for KKT systems, CORS/INFORMS Joint Int. Meeting, Banff, Alberta, Canada, May, 16-19, 2004.

· S. Bonettini, V. Ruggiero, Some iterative methods for the solution of a reduced symmetric indefinite KKT system, Conf. on High Performance Algorithms on Software of Numerical Optimization, 2004, Ischia, May, 18-20, 2004.

· Invited lecture: V. Ruggiero, Interior point method as inexact Newton method for KKT systems, Int. Workshop on the Technological Aspects of Mathematics II, Montecatini, April, 1-3 (2004).

· V. Ruggiero, Perturbed damped Newton methods for nonlinear constrained optimization problems. Part I, Part II, Numerical Methods for Local and Global Optimization: Sequential and Parallel Algorithms, Cortona, July, 14-19 (2003).

· S. Bonettini, E. Galligani, V. Ruggiero, A perturbed-damped Newton method for large scale constrained optimization, Convegno nazionale: Analisi Numerica: stato dell'arte, September 2002.

· C. Durazzi, V. Ruggiero, On a Parallel Interior-Point Method for Quadratic Programs with Special Structure, Indam School, Cortona (2001).

· C. Durazzi, V. Ruggiero, On a Parallel Interior-Point Method for Quadratic Programs with Special Structure, Workshop on Numerical Methods for Evolutionary Problems", Peschici, September, 2001.

· V. Ruggiero: Metodi iterativi per sistemi di equazioni non lineari e problemi di ottimizzazione di dimensione finita, Convegno nazionale GNCS, Bertinoro, December, 11-13 2000.

· C. Durazzi, E. Galligani, V. Ruggiero, On Interior-Point Methods for Quadratic Programs with Special Structure, Workshop on "Equilibrium Problems and Variational Models", Erice, July 2000.

· E. Galligani, V. Ruggiero, L. Zanni, Numerical solution of singly constrained convex quadratic programs subject to upper and lower bounds, SIMAI 2000, Ischia Porto, June, 6, 2000.

· Invited lecture: C. Durazzi, V. Ruggiero, G. Zanghirati, A Parallel Interior-Point Algorithm for Robust Optimization Models in Planning under Uncertainty, SIMAI 2000, Ischia Porto, June, 6, 2000.

· V. Ruggiero, L. Zanni, Splitting and Projection-type Methods for Large Scale Convex Quadratic Programs, Convegno: "Analisi Numerica: Metodi e Software Matematico", Ferrara, January, 19-21, 2000.

· V. Ruggiero, L. Zanni, Metodi di proiezione e di decomposizione per problemi di programmazione quadratica convessa di grandi dimensioni, XVI Congresso Unione Matematica Italiana, Napoli, September, 13-18, 1999.

Invited lecture: V. Ruggiero, An overview on splitting and projection methods for large-scale quadratic programs, International Workshop on Equilibrium Problems and Variational Models, Taormina, December, 3-5, 1998.

V. Ruggiero, L. Zanni, Two applications of the variable projection method for quadratic programs", International Workshop on Equilibrium Problems and Variational Models, Taormina, December, 3-5, 1998.

V. Ruggiero, L. Zanni, Splitting Methods for Constrained Quadratic Programs: Acceleration Techniques and Parallel Implementation, Operational Reasearch Society of Italy, Annual Conference: Logistics, Transportation and Quality, Treviso, September, 23-25, 1998.

V. Ruggiero, L. Zanni, Splitting methods for large scale constrained quadratic programs, 26-th Workshop: Nonlinear Optimization and Applications, Erice, June 1998.

E. Galligani, V. Ruggiero, L. Zanni, Analysis of algorithms for medium to large convex quadratic programs, International INdAM Workshop on "Numerical Methods in Optimization", Cortona, June, 9-12, 1997.

E. Galligani, V. Ruggiero, L. Zanni, Matrix splitting algorithms for decomposition of affine variational inequalities and quadratic programs, International INdAM Workshop on "Numerical Methods in Optimization", Cortona, June, 9-12, 1997.

E. Galligani, V. Ruggiero, L. Zanni, Parallel solution of large scale quadratic programs, International Workshop on High Performance Software for Nonlinear Optimization: Status & Perspective (HPSNO97)'', Ischia, June, 4-6, 1997.

E. Galligani, V. Ruggiero, L. Zanni, The eigenvalue problem for large symmetric matrices, 7th International Congress on Computational and Applied Mathematics: ICCAM 96, Lovanio, July, 21-26, 1996.

E. Galligani, V. Ruggiero, L. Zanni, Metodi di decomposizione per problemi di ottimizzazione quadratica nell'analisi dei dati, III Congresso Nazionale della SIMAI, Salice Terme, May, 27-31, 1996.

E. Galligani, V. Ruggiero, L. Zanni, Splitting methods and parallel solution of constrained quadratic programs, Workshop on ``Equilibrium Problems with Side Constraints, Lagrangean Theory and Duality II'', Scilla, May, 17-18, 1996.

V. Ruggiero, Metodi di decomposizione e architetture parallele", Giornate di Lavoro sul Calcolo Parallelo, Lucca, December, 10-12, 1996.

E. Galligani, V. Ruggiero, L. Zanni, Surface fitting for extremely large scattered data sets, International Workshop on ``Multivariate Approximation and Interpolation'', Montecatini Terme, September, 1995.

E. Galligani, V. Ruggiero, L. Zanni, Metodi iterativi per la risoluzione di problemi di programmazione quadratica con vincoli lineari , XV Congresso Unione Matematica Italiana, Padova, September, 11-16, 1995.

E. Loli Piccolomini, V. Ruggiero, F. Zama, An Application of the Indirect Approximation Problem on Heterogeneous Computer Systems, Parco '95, Gand, September, 19/22, 1995.

E. Galligani, V. Ruggiero, Implementation of Splitting Methods for Solving Block Tridiagonal Linear Systems on Transputers, Euromicro Workshop on Parallel and distributed Processing: Euromicro PDP'95, Sanremo, January, 25-27, 1995.

E. Galligani, V. Ruggiero, Analysis of Splitting Parallel Methods for Solving Block Tridiagonal Linear Systems, 2nd International Conference on Software for Multiprocessor and Supercomputers, SMS 94 TPE, Mosca, September, 19-23, 1994.

E. Loli Piccolomini, V. Ruggiero, F. Zama, A Substructuring Method for Solving The Image Restoration Problem on A Multiprocessor System, 2nd International Conference on Software for Multiprocessor and Supercomputers, SMS 94 TPE, Mosca, September, 19-23, 1994.

E. Galligani, V. Ruggiero, Il metodo della media aritmetica su sistemi multiprocessori",Convegno Nazionale di Analisi Numerica, Montecatini Terme, April, 27-29, 1994.

E. Galligani, V. Ruggiero, A Parallel Preconditioner for Block Tridiagonal Matrices, Parco '93, Grenoble, September, 7-10,1993.

E. Galligani, V. Ruggiero, ,International Workshop on Preconditioning techniques for solving large linear systems, Cortona, September, 28, October, 2, 1992.

V. Ruggiero, Precondizionatori additivi per sistemi multiprocessori , XIV Congresso Nazionale dell'UMI, Catania, September, 19-25, 1991.

E. Galligani, V. Ruggiero, Computation of the minimal eigenpair in the large sparse generalized eigenproblem using vector computers, Parallel Computing '91, Londra, September, 3-6, 1991.

I. Galligani, V. Ruggiero, Metodi di decomposizione su calcolatori multivettoriali, Supercomputing Tools for Science and Engineering, Pisa, December, 5-7, 1989.

I. Galligani, V. Ruggiero, F. Zama, Solution of the equality constrained image restoration problem on a vector computer, Parallel Computing '89, Leiden, August, 29, September, 1, 1989.

I. Galligani, V. Ruggiero, The arithmetic mean method for solving large systems of linear ordinary differential equations on a vector computer, International Meeting on Parallel Computing, Verona, September, 28-30, 1988.

I. Galligani, V. Ruggiero, International Conference on Vector and Parallel Computing, Tromso, June, 6/11 1988.

G. Casciola, V. Ruggiero, Tecniche e metodi per la realizzazione di libri elettronici, Convegno Internazionale ANTEM, Bologna, January, 30, February, 1, 1985.

V. Ruggiero, Ausilio alla didattica mediante libri elettronici su microcalcolatori, A.E.D. nell'insegnamento della Matematica, Genova, December, 3, 1983.