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Date
1st – 3rd December 2020.
Venue
Online seminar on Google Meet platform.
Registration and contacts
Please register by email to walter.boscheri@unife.it before 15th November 2020.
Note
PhD students will be granted 1 CFU for attending the entire series of lectures.
Program
1st December, 9:00 – 11:00 am
Governing equations and models for continuum mechanics Ilya Peshkov
2nd December, 9:00 – 11:00 am
Lagrangian and ALE numerical methods. Raphaël Loubère
3rd December, 9:00 – 11:00 am
ALE and structure-preserving numerical schemes for fluids and solids. Walter Boscheri
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Can a fish with limited velocity capabilities reach any point in the (possibly unbounded) ocean? In a recent paper by D. Burago, S. Ivanov and A. Novikov, "A survival guide for feeble fish", an affirmative answer has been given under the condition that the fluid velocity field is incompressible, bounded and has vanishing mean drift. This brilliant result extends some known point-to-point global controllability theorems though being substantially non constructive. We will give a fish a different recipe of how to survive in a turbulent ocean, and show how this is related to structural stability of dynamical systems by providing a constructive way to change slightly a divergence free vector field with vanishing mean drift to produce a non dissipative dynamics. This immediately leads to closing lemmas for dynamical systems, in particular to C. Pugh's closing lemma, saying also that the fish can eventually return home.
Joint work with Sergey Kryzhevich (Nova Gorica and St. Petersburg).
Organizzato dal Dipartimento di Matematica e Informatica dell’Università di Ferrara, in collaborazione con il Dipartimento di Matematica di Salerno, si svolge nelle giornate del 10 e 11 dicembre 2020 in modalità telematica, e si articola in conferenze e in laboratori.
Comitato scientifico: Maria Teresa Borgato, Alessandra Fiocca, Emilia Florio Erika Luciano, Francesco Saverio Tortoriello.
Comitato organizzatore: Maria Teresa Borgato, Maria Giulia Lugaresi, Elisa Patergnani.,
Locandina e il programma del convegno.
Per iscriversi bisogna compilare l’apposito modulo di Google reperibile al seguente link:
https://docs.google.com/forms/d/1h90yeUYFbSzEcc77QWEwZdQUJZvTiJJkk820deB83Iw/edit
Successivamente verrà inviata una mail con il link per accedere all'aula virtuale di Google Meet.
Link per partecipare all'evento in live streaming:
https://stream.meet.google.com/stream/6a8157e2-e448-49a4-a57c-7466074cc1eb
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Si presenteranno risultati di esistenza dell’attrattore globale per la dinamica asintotica di sistemi meccanici dissipativi costituiti da due travi elastiche estensibili (secondo il modello non lineare di Woinowski-Krieger) o da una trave di W-K ed un cavo (corda vibrante) quando l’accoppiamento elastico è lineare e distribuito lungo la loro lunghezza. Oltre ad un’analisi completa delle soluzioni stazionarie nei due problemi, si evidenzia che per particolari valori dei parametri elastici strutturali sorgono fenomeni di risonanza associati a infinite soluzioni statiche con due o tre modi fondamentali sovrapposti
]]>title: Mori Dream Spaces obtained by blowing-up points in projective spaces.
abstract:
The goal of the minimal model program is to construct a birational model of any complex projective variety which is as simple as possible in a suitable sense. This subject has its origins in the classical birational geometry of surfaces studied by the Italian school. In 1988 S. Mori extended the concept of minimal model to 3-folds by allowing suitable singularities on them. In 2010 there was a great breakthrough in the minimal model theory when C. Birkar, P. Cascini, C. Hacon and J. McKernan proved the existence of minimal models for varieties of log general type.
Mori Dream Spaces, introduced by Y. Hu and S. Keel in 2002, form a class of algebraic varieties that behave very well from the point of view of Mori's minimal model program. They can be algebraically characterized as varieties whose total coordinate ring, called the Cox ring, is finitely generated.
In addition to this algebraic characterization there are several algebraic varieties characterized by some positivity property of the anti-canonical divisor, such as weak Fano and log Fano varieties, that tourn out to be Mori Dream Spaces. In this talk, I will show how to obtain log Fano varieties and Mori Dream Spaces by blowing-up projective spaces in a certain number of general points.
We establish that the Lavrentiev phenomenon does not occur for autonomous
problems in the multiple integrals Calculus of Variations, provided that the inte-
grand is convex with respect to the gradient variable. The main novelty is that
no other (artificial) restriction is assumed on the integrand or on the domain. The
core of the proof is based on a new approximation result for a parametric version
of the variational problem.