Search results for "SPACES"
showing 10 items of 425 documents
A biproportional filter to compare technical and allocation coefficient variations
1997
International audience; In input-output analysis there are two alternate possibilities between Leontief's mechanism (fixed technical coefficients) and Ghosh's mechanism (fixed allocation coefficients). Testing the long term consistency of these mechanisms entails comparing input-output matrices over time. This paper challenges the value of proportional filters (separate comparison of column and row coefficients) and introduces the biproportional filter which allows simultaneous comparison of column and rows. An application is proposed using French input-output tables for 1980 and 1993. The stability of column coefficients cannot be taken for granted and generally, for any sector, both rows …
Infinitesimal Hilbertianity of Locally CAT(κ)-Spaces
2021
We show that, given a metric space (Y,d)(Y,d) of curvature bounded from above in the sense of Alexandrov, and a positive Radon measure μμ on YY giving finite mass to bounded sets, the resulting metric measure space (Y,d,μ)(Y,d,μ) is infinitesimally Hilbertian, i.e. the Sobolev space W1,2(Y,d,μ)W1,2(Y,d,μ) is a Hilbert space. The result is obtained by constructing an isometric embedding of the ‘abstract and analytical’ space of derivations into the ‘concrete and geometrical’ bundle whose fibre at x∈Yx∈Y is the tangent cone at x of YY. The conclusion then follows from the fact that for every x∈Yx∈Y such a cone is a CAT(0)CAT(0) space and, as such, has a Hilbert-like structure. peerReviewed
A characterization of Hajłasz–Sobolev and Triebel–Lizorkin spaces via grand Littlewood–Paley functions
2010
Abstract In this paper, we establish the equivalence between the Hajlasz–Sobolev spaces or classical Triebel–Lizorkin spaces and a class of grand Triebel–Lizorkin spaces on Euclidean spaces and also on metric spaces that are both doubling and reverse doubling. In particular, when p ∈ ( n / ( n + 1 ) , ∞ ) , we give a new characterization of the Hajlasz–Sobolev spaces M ˙ 1 , p ( R n ) via a grand Littlewood–Paley function.
Well-posedness and singularity formation for the Camassa-Holm equation
2006
We prove the well-posedness of Camassa--Holm equation in analytic function spaces both locally and globally in time, and we investigate numerically the phenomenon of singularity formation for particular initial data.
Gaming as a Key Approach for the Recovery Process of a Public Space: The Case Study of the Old Chemical Plant ‘Chimica Arenella’ in Palermo
2021
This poster describes the FORGE (FactOry of uRban GamEs) project, a proposal that our research group launched in partnership with the Municipality of Palermo (Italy) and other local stakeholders in 2019. FORGE will be hosted in what was previously a chemical plant (the former 'Chimica Arenella') and is an open factory designed to collect needs and to generate interventions for urban innovation. The four key terms we have used for the project are urban, game, factory and participation. In fact, FORGE employs a participatory methodological model based on the concept of game, aimed at supporting social and economic development through a platform for participatory co-design. FORGE plays also a …
Toward Livable City Centers. Hebron as a Case Study
2012
City centers of Palestinian cities face many urban planning problems; the downtown city is mostly crowded especially in the last few years, because of the increasing population of the cities and the daily migration of the residents from the nearby villages. Everyone can touch the traffic jam problem, the bad quality of urban spaces, the lack of gardens and open spaces in the city center. All this affects negatively the citizens of the city, feeling uncomfortable in the city center. Thus, this study comes to light to draw guidelines to create a comfortable and livable urban environment for people in the city center and to develop the city center to a more environmental, functional, beautiful…
Some new fixed point results in non-Archimedean fuzzy metric spaces
2013
In this paper, we introduce the notions of fuzzy $(\alpha,\beta,\varphi)$-contractive mapping, fuzzy $\alpha$-$\phi$-$\psi$-contractive mapping and fuzzy $\alpha$-$\beta$-contractive mapping and establish some results of fixed point for this class of mappings in the setting of non-Archimedean fuzzy metric spaces. The results presented in this paper generalize and extend some recent results in fuzzy metric spaces. Also, some examples are given to support the usability of our results.
Spazi aperti di comunità in ambito climatico Mediterraneo. Il caso di Hassan Fathy in Egitto
2022
The complexity of the relationship between architecture and the Mediterranean climate, in energy regimes and resource scarcity, requires special attention. Specifically, the article aims to explore how community spaces can become design subjects, intervening in climatic, environmental, social, and cultural features. Hassan Fathy’s architecture, in particular the two schools in New Gourna and Fares, offer a different key to understanding man, climate, culture, technology, and education. A relationship that is still evolving today, calling architecture back toits educational and social focus.
The Coble Quadric
2023
Given a smooth genus three curve $C$, the moduli space of rank two stable vector bundles on C with trivial determinant embeds in $\mathbb{P}^8$ as a hypersurface whose singular locus is the Kummer threefold of $C$; this hypersurface is the Coble quartic. Gruson, Sam and Weyman realized that this quartic could be constructed from a general skew-symmetric fourform in eight variables. Using the lines contained in the quartic, we prove that a similar construction allows to recover SU$_C(2, L)$, the moduli space of rank two stable vector bundles on C with fixed determinant of odd degree L, as a subvariety of $G(2, 8)$. In fact, each point $p \in C$ defines a natural embedding of SU$_C(2, \mathca…
A cognitive architecture for artificial vision
1997
Abstract A new cognitive architecture for artificial vision is proposed. The architecture, aimed at an autonomous intelligent system, is cognitive in the sense that several cognitive hypotheses have been postulated as guidelines for its design. The first one is the existence of a conceptual representation level between the subsymbolic level, that processes sensory data, and the linguistic level, that describes scenes by means of a high level language. The conceptual level plays the role of the interpretation domain for the symbols at the linguistic levels. A second cognitive hypothesis concerns the active role of a focus of attention mechanism in the link between the conceptual and the ling…