1,358 research outputs found
Regenerating Urban Spaces under Place-specific Social Contexts: a Commentary on Green Infrastructures for Landscape Conservation
This study investigates the issue of green infrastructures in contemporary cities, adopting a strategic vision for increasingly complex metropolitan regions. Green infrastructures play an important role in ecological services and biodiversity preservation, improving significantly the quality of life of residents and visitors. The social dimension of gardens and parks at local (e.g. urban district) scale and green infrastructures at larger spatial scales is also addressed, fostering the relationship between local communities and urban landscapes. With economic crisis, urban parks are increasingly considered a primary component of integrated strategies for urban regeneration with a bottom-up approach, addressing the demand for "natural landscape" in peri-urban areas. By recovering public spaces with social purposes and providing a comprehensive strategy for aesthetic improvement of common goods, the analyzed case studies give examples of specific measures for promoting environment-friendly urban regeneration strategies under place-specific social contexts
Human capital, technological spillovers and development across OECD countries
In this paper, we study the relationship between the level of development of an economy and returns to different levels of education for the panel of OECD countries over the 1965-2004 period, in a club convergence framework. The connection between growth and human capital measures of primary, secondary and tertiary education in a multiple-club spatial convergence model with non linearities and spatial dependence is considered. By decomposing total schooling into its three constituent parts, we are able to evaluate their impact on regional growth without imposing homogeneous returns from each level of education. We contribute to the identification of two regimes for OECD countries, each characterized by different returns on physical and human capital accumulation and technological spillovers. We also find that the non-monotonic pattern of convergence is strongly influenced by human capital stocks and technology diffusion process is stronger in the club less close to the technological frontier.
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<i>Morts pour la France</i>: Things and memory in the âdestroyed villagesâ of Verdun
This article considers the power of things to affect how the past is remembered in the aftermath of mass violence, through the case of the âdestroyed villagesâ ( villages dĂŠtruits) of the battlefield of Verdun, theatre in 1916 of one of the most destructive battles of World War I. As well as causing mass military death, the battle also led to the âdeathâ of nine small villages, declared to have âdied for Franceâ and incorporated into the post-war commemorative landscape of the battlefield. The article illustrates the 21st-century discourse and practices that surround the remains of these villages, from emplaced ruins to photographs and other documents. A century after the âdeathâ of the villages, people who identify as descendants of the original inhabitants gather at the sites and through these objects evoke their ancestors and the pre-war settlement, momentarily reconstituting a space that they can âinhabitâ physically, imaginatively and affectively. However, bids to restore a âvillageâ space and time are overwritten by the commemorative framework in which the sites and remains have been embedded for the past century, that identifies the âdeadâ localities with the human Fallen and their history with the moment of their âdeath for Franceâ. So, while the surviving traces of the former villages retain their power to affect and thus to evoke the pre-war, civilian past, their ability to produce a new memory for Verdun is limited by their incorporation into a memorial landscape dedicated to heroic military death for the nation. The physical expropriation of sites and vestiges during the post-war reconstruction of the battlefield and their preservation as tangible tokens of mass death has enduringly fixed and overdetermined their meaning, in a form of symbolic expropriation that limits their power to produce memory. </jats:p
Singular solutions for coercive quasilinear elliptic inequalities with nonlocal terms
We study the inequality {\rm div}\big(|x|^{-\alpha}|\nabla u|^{m-2}\nabla
u\big)\geq (I_\beta\ast u^p)u^q \quad\mbox{ in } B_1\setminus\{0\}\subset
{\mathbb R}^N, where , , , and
denotes the Riesz potential of order . We obtain sharp
conditions in terms of these parameters for which positive singular solutions
exist. We further establish the asymptotic profile of singular solutions to the
double inequality a(I_\beta\ast u^p)u^q\geq {\rm
div}\big(|x|^{-\alpha}|\nabla u|^{m-2}\nabla u\big)\geq b(I_\beta\ast u^p)u^q
\quad\mbox{ in } B_1\setminus\{0\}\subset {\mathbb R}^N, where
are constants.Comment: 26 page
Coercive elliptic systems with gradient terms
Abstract
In this paper we give a classification of positive radial solutions of the following system:
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Fujita type results for quasilinear parabolic inequalities with nonlocal terms
In this paper we investigate the nonexistence of nonnegative solutions of
parabolic inequalities of the form \begin{cases} &u_t \pm L_\mathcal A u\geq
(K\ast u^p)u^q \quad\mbox{ in } \mathbb R^N \times \mathbb (0,\infty),\, N\geq
1,\\ &u(x,0) = u_0(x)\ge0 \,\, \text{ in } \mathbb R^N,\end{cases} \qquad
(P^{\pm}) where , denotes
a weakly -coercive operator, which includes as prototype the -Laplacian
or the generalized mean curvature operator, , while stands
for the standard convolution operator between a weight satisfying
suitable conditions at infinity and . For problem we obtain a
Fujita type exponent while for we show that no such critical exponent
exists. Our approach relies on nonlinear capacity estimates adapted to the
nonlocal setting of our problems. No comparison results or maximum principles
are required
Chapter KID. Il disegno di un nuovo tipo di bicicletta
The 43rd UID conference, held in Genova, takes up the theme of âDialoguesâ as practice and debate on many fundamental topics in our social life, especially in these complex and not yet resolved times. The city of Genova offers the opportunity to ponder on the value of comparison and on the possibilities for the community, naturally focused on the aspects that concern us, as professors, researchers, disseminators of knowledge, or on all the possibile meanings of the discipline of representation and its dialogue with âothersâ, which we have broadly catalogued in three macro areas: History, Semiotics, Science / Technology. Therefore, âdialogueâ as a profitable exchange based on a common language, without which it is impossible to comprehend and understand one another; and the graphic sign that connotes the conference is the precise transcription of this concept: the title âtranslatedâ into signs, derived from the visual alphabet designed for the visual identity of the UID since 2017. There are many topics which refer to three macro sessions: - Witnessing (signs and history) - Communicating (signs and semiotics) - Experimenting (signs and sciences) Thanks to the different points of view, an exceptional resource of our disciplinary area, we want to try to outline the prevailing theoretical-operational synergies, the collaborative lines of an instrumental nature, the recent updates of the repertoires of images that attest and nourish the relations among representation, history, semiotics, sciences
Multiplicity results for generalized quasilinear critical Schr\"odinger equations in R^N
Multiplicity results are proved for solutions both with positive and negative
energy, as well as nonexistence results, of a generalized quasilinear
Schr\"odinger potential free equation in the entire R^N involving a
nonlinearity which combines a power-type term at a critical level with a
subcritical term, both with weights. The equation has been derived from models
of several physical phenomena such as superfluid film in plasma physics as well
as the self-channelling of a high-power ultra-short laser in matter.
Proof techniques, also in the symmetric setting, are based on variational
tools, including concentration compactness principles, to overcome lack of
compactness, and the use of a change of variable in order to deal with a well
defined functional
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