1,354,716 research outputs found
Existence, uniqueness and
No full textWe consider the gradient flow of the Ambrosio–Tortorelli functional, proving existence, uniqueness and L2t(H2x) ∩ L∞t(H1x) ∩ H1t(L2x) regularity of the solution in dimension 2. Such functional is an approximation in the sense of Γ-convergence of the Mumford–Shah functional often used in problems of image segmentation and fracture mechanics. The strategy of the proof essentially follows the one of []Feng and Prohl, M2AN Math. Model. Numer. Anal. 38 (2004) 291–320] but the crucial estimate is attained employing a different technique, and in the end it allows to prove better estimates than the ones obtained in [Feng and Prohl, M2AN Math. Model. Numer. Anal. 38 (2004) 291–320]. In particular we prove that if U ⊂ ℝ2 is a bounded C2 domain, the initial data (u0, z0) ∈ [H1(U)]2 with 0 ≤ z0 ≤ 1, then for every T > 0 there exists a unique gradient flow (u(t), z(t)) of the Ambrosio–Tortorelli functional such that (u, z) ∈ [L2(0, T; H2(U)) ∩ L∞(0,T;H1(U)) ∩H1(0,T;L2(U)]2 while previously such regularity was known only for short times
The Fable of the Hot Dog Vendor
No full textHere is a Christmas tribute to hard work, to our many wonderful Stanislaus customers and their families who share our commitment to excellence. It is signed as a gift from Dino and Giovanna Cortopassi, owners of Stanislaus Food Products. The story tells of a poor immigrant setting up a hot dog stand selling the best hot dogs on the best buns with the best condiments--six of them on the first day of business, with the profits reinvested the next day in twelve hot dogs…. The business did well, and after years his son went off to college. He came back and talked the father in a time of recession into selling less than the best, but sales only slumped as a result. The son went on to work for a big chain, and the father finally sold the hot dog stand--to a hard-working young immigrant with the bright idea of selling the best hot dogs. Two things strike me as curious about the book: the self-congratulatory praise of hard work and good taste as appropriate for Christmas, and the negative character of the fable in the light of the lesson that Dino Cortopassi formulates this way at the end: Fortunately, long before I went to college, my immigrant father taught me 'You can't make good wine from bad grapes.' I believe that this book marks the first mention of hot dogs in this collection!This is a hardbound book (hard cover)Signed by Dino and Giovanna Cortopassi and also at the end by the latte
A generalised Nehari manifold method for a class of non-linear Schrödinger systems in R3
No full textWe study the existence of positive solutions of a particular elliptic system in R3 composed of two non linear stationary Schrödinger equations (NLSEs), that is -∈2Δu + V(x)u = hv(u, v), -∈2Δv + V(x)v = hu(u, v). Under certain hypotheses on the potential V and the non linearity h, we manage to prove that there exists a solution (u∈, v∈) that decays exponentially with respect to local minima points of the potential and whose energy tends to concentrate around these points, as ∈ → 0. We also estimate this energy in terms of particular ground state energies. This work follows closely what is done in [6], although here we consider a more general non linearity and we restrict ourselves to the case where the domain is R3
Italian Light, 100 lampade della collezione Cortopassi
No full textThe book, using as a pretext 100 lamps of Cortopassi collection, highlights, a history made of little events, single designers, fortuitous coincidences and exhibitions appointment constantly repeated to mark and highlight the continuous trasformations. A history made of individual researches developed for decades in an endless need for self-surprise, self-reference, self-promoting, self-criticism. Company histories linked to single or infinite designers, single or infinite products typologies, single or infinite images, are features allowing manifold historical reading in which the only certainty is the need of classifyng, in a non-reductive form, all the design made in the last 60s in Italy
Italian Light, 100 lampade della collezione Cortopassi
No full textThe book, using as a pretext 100 lamps of Cortopassi collection, highlights, a history made of little events, single designers, fortuitous coincidences and exhibitions appointment constantly repeated to mark and highlight the continuous trasformations. A history made of individual researches developed for decades in an endless need for self-surprise, self-reference, self-promoting, self-criticism. Company histories linked to single or infinite designers, single or infinite products typologies, single or infinite images, are features allowing manifold historical reading in which the only certainty is the need of classifyng, in a non-reductive form, all the design made in the last 60s in Italy
An explicit Euler method for Sobolev vector fields with applications to the continuity equation on non cartesian grids
No full textWe prove a novel stability estimate in between the regular Lagrangian flow of a Sobolev vector field and a piecewise affine approximation of such flow. This approximation of the flow is obtained by a (sort of) explicit Euler method, and it is the crucial tool to prove approximation results for the solution of the continuity equation by using the representation of the solution as the push-forward via the regular Lagrangian flow of the initial datum. We approximate the solution in two ways, using different approximations for both the flow and the initial datum. In the first case we give an estimate, which however holds only in probability, of the Wasserstein distance between the solution of the continuity equation and a discrete approximation of such solution. The approximate solution is defined as the push-forward of weighted Dirac deltas (whose centers are chosen in a probabilistic way). In the second case we give a deterministic estimate of the Wasserstein distance using a slightly different approximation of the regular Lagrangian flow and requiring more regularity on the velocity field than in the previous case. An advantage of both approximations is that they provide an algorithm which is easily parallelizable and does not rely on any particular structure of the mesh with which we discretize (only in space) the domain
Inhibition of mitochondrial function induces an integrated stress response in oligodendroglia.
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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