5,456 research outputs found
An adaptive finite element approximation of a variational model of brittle fracture
No full textThe energy of the Francfort–Marigo model of brittle fracture can be approximated, in the sense of Gamma-convergence, by the Ambrosio–Tortorelli functional. In this work, we formulate and analyze two adaptive finite element algorithms for the computation of its (local) minimizers. For each algorithm, we combine a Newton-type method with residual-driven adaptive mesh refinement. We present two theoretical results which demonstrate convergence of our algorithms to local minimizers of the Ambrosio–Tortorelli functional
Literacy in Neapolitan Women's Convents in the Middle Ages and the Contribution of Digital Archives on Monasterium.Net
No full textAntonella Ambrosio seeks a viable way of carrying out research on this topic: the palaeographic analysis of the few available sources using a multidisciplinary approach that combines diplomatics, archival, and historical research. This approach ensures the appropriate contextualization of the source both historically and culturally. In "Literacy in Neapolitan Women's Convents: An Example of Female Handwriting in a Late Fifteenth-Century Accounts Ledger", Ambrosio provides a case study, analysing a single piece of handwriting evidence. The source is an accounts ledger from the Dominican convent of Santi Pietro e Sebastiano compiled in the second half of the fifteenth century, from 1485 to 1496. Using an analytical approach, the author has identified the handwriting of a particular (anonymous) nun from the convent; Ambrosio studies the script the nun used and formulates hypotheses about her cultural background and how she learned to write. The palaeographic analysis is fully contextualized thanks to the reconstruction of the old convent archive, a reconstruction helped by using digital technologies now accessible online at Monasterium.net. As Ambrosio's work demonstrates, technological advances may aid codicological work but careful palaeographic analysis is necessary to ascertain the participation of female scribes. In this case we witness the scribal development of a nun who began with a basic knowledge of writing and who went on to perform her practical task not well but adequately for the purpose
Correction to: Malignant epithelioid neoplasm of the ileum with ACTB-GLI1 fusion mimicking an adnexal mass (BMC Women's Health, (2022), 22, 1, (104), 10.1186/s12905-022-01679-0)
No full textFollowing publication of the original article (1), The author names were incorrectly published as Ambrosio Marco, Virgilio Agnese, Raffone Antonio, Arena Alessandro, Raimondo Diego, Alletto Andrea, Seracchioli Renato and Casadio Paolo. But this should have been Marco Ambrosio, Agnese Virgilio, Antonio Raffone, Alessandro Arena, Diego Raimondo, Andrea Alletto, Renato Seracchioli, and Paolo Casadio. The original article has been updated
Literacy in Neapolitan Women’s Convents: An Example of Female Handwriting in a Late Fifteenth-Century Accounts Ledger
No full textThis paper is about a research i on the literacy and writing skills of Neapolitan sisters in medieval convents, due to the lack of adequate historical study of such nuns and the extremely complex nature of the documentary sources. Surviving evidence is scattered far and wide, and the old convent archives have been dispersed. Given the state of the survivals, Antonella Ambrosio seeks a viable way of carrying out research on this topic: the palaeographic analysis of the few available sources using a multidisciplinary approach that combines diplomatics, archival, and historical research. This approach ensures the appropriate contextualization of the source both historically and culturally. In ‘Literacy in Neapolitan Women’s Convents: An Example of Female Handwriting in a Late Fifteenth-Century Accounts Ledger’, Ambrosio provides a case study, analysing a single piece of handwriting evidence. The source is an accounts ledger from the Dominican convent of Santi Pietro e Sebastiano compiled in the second half of the fifteenth century, from 1485 to 1496. Using an analytical approach, the author has identified the handwriting of a particular (anonymous) nun from the convent; Ambrosio studies the script the nun used and formulates hypotheses about her cultural background and how she learned to write. The palaeographic analysis is fully contextualized thanks to the reconstruction of the old convent archive, a reconstruction helped by using digital technologies now accessible online at Monasterium.net. As Ambrosio’s work demonstrates, technological advances may aid codicological work but careful palaeographic analysis is necessary to ascertain the participation of female scribes. In this case we witness the scribal development of a nun who began with a basic knowledge of writing and who went on to perform her practical task not well but adequately for the
purpose
Periodic solutions for the non-local operator (−∆ + m^2)^s − m^2s with m ≥ 0
No full textBy using variational methods, we investigate the existence of T-periodic solutions to
\begin{equation*}
\left\{
\begin{array}{ll}
[(-\Delta_{x} + m^{2})^{s} -m^{2s}] u= f(x, u) &\mbox{ in } (0, T)^{N}, \\
u(x+ Te_{i})= u(x) &\mbox{ for all } x\in \mathbb{R}^{N}, i= 1, \dots, N,
\end{array}
\right.
\end{equation*}
where , , , and is a continuous function, -periodic in the first variable, verifying the Ambrosetti-Rabinowitz condition, with a polynomial growth at rate
An adaptive finite element approximation of a generalized Amrosio-Tortorelli functional
No full textThe Francfort–Marigo model of brittle fracture is posed in terms of the minimization of a highly irregular energy functional. A successful method for discretizing the model is to work with an approximation of the energy. In this work a generalized Ambrosio–Tortorelli functional is used. This leads to a bound-constrained minimization problem, which can be posed in terms of a variational inequality. We propose, analyze and implement an adaptive finite element method for computing (local) minimizers of the generalized functional
Anisotropic surface measures as limits of volume fractions
No full textIn this paper we consider the new characterization of the perimeter of a measurable set in Rn recently studied by Ambrosio, Bourgain, Brezis and Figalli. We modify their approach by using, instead of cubes, covering families made by translations of a given open bounded set with Lipschitz boundary. We show that the new functionals converge to an anisotropic surface measure, which is indeed a multiple of the perimeter if we allow for isotropic coverings (e.g. balls or arbitrary rotations of the given set). This result underlines that the particular geometry of the covering sets is not essential
Continuity equations and ODE flows with non-smooth velocity
No full textIn this paper we review many aspects of the well-posedness theory for the Cauchy problem for the continuity and transport equations and for the ordinary differential equation (ODE). In this framework, we deal with velocity fields that are not smooth, but enjoy suitable 'weak differentiability' assumptions. We first explore the connection between the partial differential equation (PDE) and the ODE in a very general non-smooth setting. Then we address the renormalization property for the PDE and prove that such a property holds for Sobolev velocity fields and for bounded variation velocity fields. Finally, we present an approach to the ODE theory based on quantitative estimates
On the duality between -modulus and probability measures
No full textMotivated by recent developments on calculus in metric measure spaces
, we prove a general duality principle between
Fuglede's notion of -modulus for families of finite Borel measures in
and probability measures with barycenter in , with dual exponent of . We apply this general duality
principle to study null sets for families of parametric and non-parametric
curves in . In the final part of the paper we provide a new proof,
independent of optimal transportation, of the equivalence of notions of weak
upper gradient based on -Modulus (Koskela-MacManus '98, Shanmugalingam '00)
and suitable probability measures in the space of curves (Ambrosio-Gigli-Savare
'11
La frenologia al tribunale della fede: Luigi Ferrarese e “l’organo dell’anima"
No full textIl presente lavoro intende approfondire il problematico rapporto tra la dottrina frenologica e l’autorità religiosa, la quale ebbe a criticarne aspramente i presupposti scientifici e lo sfondo antimetafisico. È nostra intenzione provare a chiarire come, sullo fondo della contrapposizione dottrinale, abbia preso progressivamente forma un contrasto ben più ampio, di tipo squisitamente politico, volto a contrapporre una complessa trama di autorità e di poteri in ambito sociale, medico e giuridico. Il saggio si compone di tre parti. La prima si soffermerà sulle origini di tale contrasto, che coinvolgeranno la figura e gli scritti di Joseph Gall, medico tedesco fondatore della frenologia. La seconda approfondirà, in tale prospettiva, l’opera del frenologo Luigi Ferrarese, le cui posizioni sfociarono, a partire dal 1838, in una serie di richiami della Santa Sede, culminati con la reclusione e la sospensione dell’incarico presso la Real Casa de’ Matti di Aversa. L’ultima parte del lavoro riporta nella sua interezza, opportunamente tradotto, il resoconto di una serie di incontri avvenuti nel 1844 tra il medico lucano ed il celebre frenologo scozzese George Combe
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