Search results for " Tori"

Splittings of Toric Ideals

2019

Let $I \subseteq R = \mathbb{K}[x_1,\ldots,x_n]$ be a toric ideal, i.e., a binomial prime ideal. We investigate when the ideal $I$ can be "split" into the sum of two smaller toric ideals. For a general toric ideal $I$, we give a sufficient condition for this splitting in terms of the integer matrix that defines $I$. When $I = I_G$ is the toric ideal of a finite simple graph $G$, we give additional splittings of $I_G$ related to subgraphs of $G$. When there exists a splitting $I = I_1+I_2$ of the toric ideal, we show that in some cases we can describe the (multi-)graded Betti numbers of $I$ in terms of the (multi-)graded Betti numbers of $I_1$ and $I_2$.

Giovanni Curioni. Profilo di un Maestro e di uno storiografo

2008

Cammeo bio-bibliografico di un ingegnere docente storiografo presso la Facoltà di Ingegneria di Torino

Particle distribution in dilute solid liquid unbaffled tanks via a novel laser sheet and image analysis based technique

2013

The availability of experimental information on particle distribution inside stirred tanks is a topic of great importance for many industrial applications such as catalysis and polymerization. The measurement of solid particle distribution is not simple and the development of suitable measuring techniques is still an open problem in chemical engineering research. In this work, a non-intrusive optical technique for measuring particle concentration fields in solid–liquid systems is discussed. The “Laser Sheet Image Analysis” (LSIA) technique described here makes use of a laser sheet, a digital camera for image acquisition and a suitable procedure for post-processing. It is able to provide sol…

Regularity and h-polynomials of toric ideals of graphs

2020

For all integers 4 ≤ r ≤ d 4 \leq r \leq d , we show that there exists a finite simple graph G = G r , d G= G_{r,d} with toric ideal I G ⊂ R I_G \subset R such that R / I G R/I_G has (Castelnuovo–Mumford) regularity r r and h h -polynomial of degree d d . To achieve this goal, we identify a family of graphs such that the graded Betti numbers of the associated toric ideal agree with its initial ideal, and, furthermore, that this initial ideal has linear quotients. As a corollary, we can recover a result of Hibi, Higashitani, Kimura, and O’Keefe that compares the depth and dimension of toric ideals of graphs.

High significance measurement of the terrestrial neutrino flux with the Borexino detector

2015

International audience; We review the geoneutrino measurement with Borexino from 2056 days of data taking.

Infrastructure as interface. Thinking the urban and the high -speed station: italian case-studies.

2011

This presentation will document some results of an ongoing research focusing on the role of infrastructure in contemporary design practice. The methodology is based on critical design theory and combines theoretical aspects with a case-study approach, at the junction of infrastructure, urban design and architecture. It is already well documented that 19th and 20th century infrastructure have deeply affected their programs in order to face new challenges over the last 30 decades. Railway stations are leading examples in this fields: they have gradually implemented their design, that already integrated commercial spaces and facilities, until involving in public space transformation. Instead, …

Approximate renormalization-group transformation for Hamiltonian systems with three degrees of freedom

1999

We construct an approximate renormalization transformation that combines Kolmogorov-Arnold-Moser (KAM)and renormalization-group techniques, to analyze instabilities in Hamiltonian systems with three degrees of freedom. This scheme is implemented both for isoenergetically nondegenerate and for degenerate Hamiltonians. For the spiral mean frequency vector, we find numerically that the iterations of the transformation on nondegenerate Hamiltonians tend to degenerate ones on the critical surface. As a consequence, isoenergetically degenerate and nondegenerate Hamiltonians belong to the same universality class, and thus the corresponding critical invariant tori have the same type of scaling prop…

CULTURA DELLA RAGIONEVOLEZZA DEI TEMPI PROCESSUALI, GARANZIE CEDU E RIMEDI INTERNI:IL CASO ITALIANO TRA ESPERIENZE E PROSPETTIVE DI RIFORMA

Mai come negli ultimi decenni il volto della Giustizia è apparso così contrassegnato da rugosità e increspature che ne hanno evidenziato il suo lento stato di senescenza e deterioramento. Agli occhi della collettività ha, ormai, assunto l’aspetto di intollerabile luogo d’inefficienza e sono tutti in grado di riconoscerne il suo male maggiore, radicato nell’estenuante lentezza dei suoi riti. Invero, il tempo è un elemento imprescindibile della qualità del processo sotto una duplice prospettiva: “occorre tempo per decidere, ma occorre altresì decidere in tempo”, e il tempo fissato per la decisione giudiziaria è un tempo dalla necessaria ragionevole durata. Il perseguimento di questa durata ra…

Blown-up toric surfaces with non-polyhedral effective cone

2020

We construct examples of projective toric surfaces whose blow-up at a general point has a non-polyhedral pseudo-effective cone, both in characteristic $0$ and in every prime characteristic $p$. As a consequence, we prove that the pseudo-effective cone of the Grothendieck-Knudsen moduli space $\overline M_{0,n}$ of stable rational curves is not polyhedral for $n\geq 10$ in characteristic $0$ and in characteristic $p$, for all primes $p$. Many of these toric surfaces are related to a very interesting class of arithmetic threefolds that we call arithmetic elliptic pairs of infinite order. Their analysis in characteristic $p$ relies on tools of arithmetic geometry and Galois representations in …

Progetto Periferie, Torino. Corviale, Roma. Le Vele, Napoli

2003

Schede per l’inchiesta Periferie