- NumPI - Mailing list — Dipartimento di Matematica, UniPI

Short Course by Alice Cortinovis
by Nicola Guglielmi 13 Apr '26

13 Apr '26

Dear all, This is a gentle reminder of the short course Introduction to randomized numerical linear algebra by Professor Alice Cortinovis (University of Pisa). Notice that the first lecture is scheduled at 4.30 today (April 13) in Aurora (ex-ISEF) building MLH room. It will be also possible to follow the course online. Best wishes, Nicola https://indico.gssi.it/event/938/ Ps details can be found here ----------------------------------------------------------------------------------------------------- Nicola Guglielmi Professor of Numerical Analysis Deputy Rector, Gran Sasso Science Institute https://www.gssi.it/people/professors/lectures-maths/item/545-guglielmi-nic… ------------------------------------------------------------------------------------------------------- -- You received this message because you are subscribed to the Google Groups "nomads-list" group. To unsubscribe from this group and stop receiving emails from it, send an email to nomads-list+unsubscribe(a)gssi.it. To view this discussion visit https://groups.google.com/a/gssi.it/d/msgid/nomads-list/CAMe-9vEPyTEV14OU2W…. For more options, visit https://groups.google.com/a/gssi.it/d/optout.

1 1

[Indico] [Event reminder] Stochastic Optimisation algorithms in CIL (14/04/2026, 11:00 Europe/Rome)
by Fabio Durastante 13 Apr '26

13 Apr '26

Title: Stochastic Optimisation algorithms in CIL, Speaker(s): Prof. Edoardo Pasca, UK Science and Technology Facilities Council (STFC), Date and time: 14 Apr 2026, 11:00 (Europe/Rome), Lecture series: Seminar on Numerical Analysis, Venue: Dipartimento di Matematica (Aula Magna (DM)). Address: Largo Bruno Pontecorvo, 5 – 56127 Pisa You can access the full event here: https://events.dm.unipi.it/e/340 Abstract -------- Stochastic optimization algorithms are commonly used in the training of machine learning models because they ensure progress towards the solution while reducing the per-iteration computational costs. This seminar is about the Stochastic Optimization algorithms available in the Core Imaging Library (CIL), including usage on real data at scale. CIL is an open source mainly Python framework for tomographic imaging originally developed for X-ray Computed Tomography. CIL has been used in various fields such as Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), and Synthetic Aperture Radar (SAR). Note ---- Reminder for tomorrow's seminar -- Indico :: Email Notifier https://events.dm.unipi.it/e/340

1 0

Training session and seminar on Computational Imaging
by Silvia Gazzola 08 Apr '26

08 Apr '26

Dear all, Next Tuesday (14/04/2026) we will host Dr. Edoardo Pasca<https://ccpi.ac.uk/people/edoardo-pasca/>, Head of the Computed Tomography and Imaging group at the Scientific Computing division of the national UK Science and Technology Facilities Council (STFC<https://www.ukri.org/councils/stfc/>). He is an expert in solution methods and software for inverse problems in image reconstruction. See below for a more complete biography. Dr. Edoardo Pasca leads a team of scientists that develop the Core Imaging Library software (CIL<https://ccpi.ac.uk/cil/>). CIL is an open source, mainly Python, framework for tomographic imaging originally developed for X-ray Computed Tomography. CIL has been used in various fields such as Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), and Synthetic Aperture Radar (SAR). Here are the events scheduled for the day: Workshop (hands on session) on CIL for CT reconstruction. TIME: 9:15-11:00 (morning session), 14:00-16:30 (afternoon session) LOCATION: TBD, Dipartimento di Matematica Address: Largo Bruno Pontecorvo, 5 – 56127 Pisa The event is free but registration is mandatory: if you’d like to attend, please fill in this form https://docs.google.com/forms/d/e/1FAIpQLSezb6BzvAwyIvGW-lLiQSnDVP0U655XW3D… by 12/04/2026. ABSTRACT: We will run a group-based practical session using CIL in Python for X-ray CT data manipulation and reconstruction. An introduction on concepts of X-ray CT data acquisition, optimization, iterative reconstruction algorithms and regularization will be given, followed by exercises in CIL. No software installation will be required: the sessions will be based on our Jupyter notebook training material<https://github.com/TomographicImaging/CIL-Demos>, and participants will have access to the material in the cloud. Knowledge of Python or object oriented programming is not mandatory to attend the event. By the end of the session you will know more about computational imaging and potentially be ready to use CIL for your research. Seminar (part of the Numerical Analysis seminar series) TITLE: Stochastic Optimisation algorithms in CIL TIME: 11:00-12:00 LOCATION: Dipartimento di Matematica (Aula Magna (DM)) Address: Largo Bruno Pontecorvo, 5 – 56127 Pisa ABSTRACT: Stochastic optimization algorithms are commonly used in the training of machine learning models because they ensure progress towards the solution while reducing the per-iteration computational costs. In this seminar, I will talk about the Stochastic Optimization algorithms available in the Core Imaging Library (CIL) and show some usage on real data at scale. Biography: Edoardo Pasca<https://ccpi.ac.uk/people/edoardo-pasca/> graduated in Physics and obtained a PhD in material science and technology at the University of Florence. After working as a post-doc in experimental condensed matter physics, he transitioned to software development and imaging. He now leads the Computed Tomography and Imaging group in the Scientific Computing of the Science Technology Facilities Council (STFC). The group supports material-science and medical-imaging scientists as well as UK national facilities such as the ISIS Neutron and Muon source, the UK synchrotron Diamond Light Source, the Central Laser Facility (CLF) and their users. Please do not hesitate to contact me if you need any additional information. Best wishes, Silvia Gazzola ============= Dr Silvia Gazzola Dipartimento di Matematica Università di Pisa https://sites.google.com/view/silviaspersonalwebpage/silvias-homepage ---------------------------------------------------------------------------------------------------------------------------------------------------------- You may receive this email outside my normal working hours — no response is expected outside your working hours ----------------------------------------------------------------------------------------------------------------------------------------------------------

1 0

Fwd: Talk by Britt van Veggel - April 29th
by Fabio Durastante 08 Apr '26

08 Apr '26

Dear all, I am forwarding the announcement below from the FLorence OPtimization talkS (FLOPS) mailing list, as the topic may be of interest to many of you. Please find the details of the seminar hereunder. Best, Fabio -------- Messaggio Inoltrato -------- Oggetto: Talk by Britt van Veggel - April 29th Data: Wed, 8 Apr 2026 04:18:43 -0700 (PDT) Mittente: FLOPtalks <floptalks-group(a)unifi.it> A: FLOPtalks <floptalks-group(a)unifi.it> CC: b.w.j.r.vanveggel(a)uva.nl Dear colleagues and friends, we are pleased to announce next seminar of the FLorence OPtimization talkS (FLOPS) series. Britt van Veggel <https://www.uva.nl/en/profile/v/e/b.w.j.r.vanveggel/b.w.j.r.van-veggel.html>,PhD student at University of Amsterdam,will give a talk entitled "Heatmaps for maximum coverage facility location optimization". The talk will be on *April** 29th at 2:00 p.m. *in**Room 221 Centro didattico Morgagni <https://g.co/kgs/uuxpeDA>. The abstract of the talk is available at the following link <https://sites.google.com/unifi.it/floptalks/home?authuser=3> (as well as in the attached poster). Best regards, Marianna & Margherita -- You received this message because you are subscribed to the Google Groups "FLOPtalks" group. To unsubscribe from this group and stop receiving emails from it, send an email to floptalks-group+unsubscribe(a)unifi.it. To view this discussion, visit https://groups.google.com/a/unifi.it/d/msgid/floptalks-group/b996480f-7c2e-… <https://groups.google.com/a/unifi.it/d/msgid/floptalks-group/b996480f-7c2e-…>.

1 0

[Indico] [Event reminder] Stochastic Optimisation algorithms in CIL (14/04/2026, 11:00 Europe/Rome)
by Fabio Durastante 08 Apr '26

08 Apr '26

Title: Stochastic Optimisation algorithms in CIL, Speaker(s): Prof. Edoardo Pasca, UK Science and Technology Facilities Council (STFC), Date and time: 14 Apr 2026, 11:00 (Europe/Rome), Lecture series: Seminar on Numerical Analysis, Venue: Dipartimento di Matematica (Aula Magna (DM)). Address: Largo Bruno Pontecorvo, 5 – 56127 Pisa You can access the full event here: https://events.dm.unipi.it/e/340 Abstract -------- Stochastic optimization algorithms are commonly used in the training of machine learning models because they ensure progress towards the solution while reducing the per-iteration computational costs. This seminar is about the Stochastic Optimization algorithms available in the Core Imaging Library (CIL), including usage on real data at scale. CIL is an open source mainly Python framework for tomographic imaging originally developed for X-ray Computed Tomography. CIL has been used in various fields such as Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), and Synthetic Aperture Radar (SAR). Note ---- Next seminar in the NUMPI series -- Indico :: Email Notifier https://events.dm.unipi.it/e/340

1 0

[Indico] [Event reminder] A TAME method for the Inverse Laplace Transform of tame functions (31/03/2026, 11:00 Europe/Rome)
by Fabio Durastante 30 Mar '26

30 Mar '26

Title: A TAME method for the Inverse Laplace Transform of tame functions, Speaker(s): Nikita Deniskin, Scuola Normale Superiore, Date and time: 31 Mar 2026, 11:00 (Europe/Rome), Lecture series: Seminar on Numerical Analysis, Venue: Dipartimento di Matematica (Aula Magna). You can access the full event here: https://events.dm.unipi.it/e/339 Abstract -------- The Laplace transform and its inverse are widely used tools in both theoretical and applied contexts. However, while the direct Laplace transform is stable, the inverse Laplace transform is an inherently ill-posed problem, which makes its accurate computation challenging; this has led to extensive research in numerical methods for the inverse Laplace transform. In this talk, we focus on a family of algorithms, called Abate-Whitt methods, which recover the original function via linear combinations of evaluations of the transform. We relate the accuracy, with theoretical bounds, of the Abate-Whitt method to an approximation problem: constructing a rational approximation of the exponential $e^z$ on certain domains of the complex plane. We propose a new method, dubbed TAME, based on the AAA algorithm for rational approximation. TAME is especially effective for problems in queueing theory, in particular in analyzing phase-type distributions (Markov chains), and in computing the first return times in fluid queues. Here evaluations of the Laplace transform are (relatively) expensive, so it is highly important to minimize the number of needed evaluations. Joint work with Federico Poloni, arXiv:2510.14799. Note ---- Reminder of tomorrow’s seminar -- Indico :: Email Notifier https://events.dm.unipi.it/e/339

1 0

[Indico] Nikita Deniskin, A TAME method for the Inverse Laplace Transform of tame functions - 31 Mar 2026
by Fabio Durastante 18 Mar '26

18 Mar '26

1 0

Fw: Talk by Francesco Rinaldi - March 27th
by Fabio Durastante 04 Mar '26

04 Mar '26

Dear Everybody, Please find attached the announcement for an upcoming FLOPtalks from our friends in Florence. The seminar may be of interest to many of you. Best, Fabio ________________________________ Da: FLOPtalks <floptalks-group(a)unifi.it> Inviato: martedì, marzo 3, 2026 4:45:36 PM A: FLOPtalks <floptalks-group(a)unifi.it> Oggetto: Talk by Francesco Rinaldi - March 27th Dear colleagues and friends, we are pleased to announce next seminar of the FLorence OPtimization talkS (FLOPS) series. Francesco Rinaldi<https://www.math.unipd.it/dipartimento/persone/francesco.rinaldi/>, Full Professor at Università di Padova, will give a talk entitled "Projection-Free Optimization in Action: Scalable Methods for Network Science and Graph Learning". The talk will be on March 27th at 11:00 a.m. in Room 107 Centro didattico Morgagni<https://g.co/kgs/uuxpeDA>. The abstract of the talk is available at the following link<https://sites.google.com/unifi.it/floptalks/home?authuser=3> (as well as in the attached poster). Best regards, Marianna & Margherita -- You received this message because you are subscribed to the Google Groups "FLOPtalks" group. To unsubscribe from this group and stop receiving emails from it, send an email to floptalks-group+unsubscribe(a)unifi.it<mailto:floptalks-group+unsubscribe@unifi.it>. To view this discussion, visit https://groups.google.com/a/unifi.it/d/msgid/floptalks-group/7e4a6617-a53a-…<https://groups.google.com/a/unifi.it/d/msgid/floptalks-group/7e4a6617-a53a-…>.

1 0

Analysis Seminar Announcement - "Non-matching coupling in fluid–structure interaction: constraints, singular forcing, and dimensional reduction" - Luca Heltai
by Fabio Durastante 16 Feb '26

16 Feb '26

Dear Everybody, Please find attached the announcement for an upcoming seminar by Luca Heltai on topics at the intersection of Analysis and Numerical Analysis. This seminar is part of the Analysis seminar series and may be of interest to many of you. Web announcement: https://www.dm.unipi.it/seminario/?id=698b2491dd82ea23a81f8461 Best regards, Fabio * Analysis Seminar: *Non-matching coupling in fluid–structure interaction: constraints, singular forcing, and dimensional reduction *Speaker: *Luca Heltai *Location: *18/02/2026 - 10.00-11.00, Aula Magna (Department of Mathematics) *Abstract.* Fluid–structure interaction problems often involve coupling conditions imposed on interfaces whose geometry is complex, thin, or evolving in time. In many relevant regimes, enforcing such conditions on matching discretizations is either impractical or conceptually inadequate, motivating the use of non-matching and immersed formulations. In this talk, we present an analytical overview of non-matching coupling methods for fluid–structure interaction, interpreting interface conditions as functional constraints, imposed on sets of varying dimensions. We focus on Lagrange multiplier formulations (classical, distributed, and reduced) and discuss their well-posedness and stability properties at both the continuous and discrete levels. A central theme of the talk is the analysis of singular forcing terms generated by non-matching constraints. On the one hand, variational formulations of non-matching coupling typically induce a loss of global regularity in the solution. We show that this loss is in fact a purely local phenomenon, and we characterize it using weighted Sobolev spaces, thereby recovering optimal approximation properties away from the interface. On the other hand, non-matching fluid–structure interaction formulations can be reinterpreted as Navier–Stokes-type problems with singular forcing terms. While classical Immersed Boundary Methods employ regularized Dirac distributions primarily for implementation purposes, we provide a general framework showing that regularization and analysis are not separate issues. In particular, we establish a rigorous connection between regularized and variational formulations, proving that suitably chosen regularizations lead to equivalent finite element approximations, with comparable accuracy and computational cost. We then address dimensional reduction strategies for slender or thin structures, showing how mixed-dimensional models naturally arise as asymptotic limits of non-matching coupling formulations. We discuss how reduced Lagrange multiplier spaces can be designed to preserve well-posedness and stability uniformly with respect to vanishing geometric scales. The presented results provide a unified functional-analytic perspective on a class of non-matching methods used in fluid–structure interaction and related problems, highlighting the mechanisms underlying their stability, accuracy, and robustness across dimensions.

1 0

seminario Beneventano domani
by Beatrice Meini 12 Jan '26

12 Jan '26

Buonasera, scusate lo scarso preavviso. Domani alle 14, in Saletta Riunioni al Dip Matematica, Pierfrancesco Beneventano, un nostro ex studente e ora post-doc a MIT, terra' il seminario: Edge of Stochastic Stability: SGD does not train neural networks as you expect it https://www.dm.unipi.it/en/seminar/?id=694aba9c2ac7f6b23978e5a0 Saluti, Beatrice

1 0