9,506 research outputs found

    Cosmological implications of an evolutionary quantum gravity

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    The cosmological implications of an evolutionary quantum gravity are analyzed in the context of a generic inhomogeneous model. The Schr\"{o}dinger problem is formulated and solved in the presence of a scalar field, an ultrarelativistic matter and a perfect gas regarded as the dust-clock. Considering the actual phenomenology, it is shown how the evolutionary approach overlaps the Wheeler-DeWitt one.Comment: 4 pages; to appear in the proceedings of the II Stueckelberg Workshop, Int.J.Mod.Phys.A, references adde

    Mitigation technologies for counteracting the UHI effects and for improving outdoor thermal comfort in mediterranean urban open spaces: a study of vegetation and cool materials effects on pedestrian comfort in Rome

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    The present study investigates the influence of building materials, traditional as well as innovative, and vegetated urban surfaces on the urban microclimate and on pedestrian outdoor thermal comfort in a typical Mediterranean city: Rome. It focuses the attention on selected mitigation technologies aiming to increase the albedo of cities: high reflective materials called cool colored materials, and the use of vegetative surfaces: green roofs, green walls and trees, with the main purpose to test, verify and quantify the overall microclimate mitigation and thermal performance of the aforementioned strategies, The study proposes and analyses, through CFD calculations (ENVImet v.4.0), five renovations scenarios: applying cool materials and vegetation on roofs, walls and pavements of the selected square. In order to support planning authorities and researches by going beyond the traditional way of urban heat island studies, the present study aims to highlight the multiple effects of cool colored materials on human comfort and to investigates which could be the best combination materials in terms of mitigation of ambient temperatures and pedestrian thermal stress. Therefore, air temperature as well as the physiologically equivalent temperature (PET) were applied to take into account the effect of the variations of urban materials on human comfort, the studies focuses the attention and draw its conclusions through the comparison of the Envimet thermal maps and the values of the different scenarios in terms of deltas variations. The results show the negative effect of cool colored materials on human thermal comfort when applied isolated to surfaces in direct contact with pedestrians, such as pavements and urban façades, nevertheless it underlines the benefit associated with a mixed combination of cool materials and trees, setting the path for further research in this direction

    Window-Dependent Bases for Efficient Representations of the Stockwell Transform

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    Since its appearing in 1996, the Stockwell transform (S-transform) has been applied to medical imaging, geophysics and signal processing in general. In this paper, we prove that the system of functions (so-called DOST basis) is indeed an orthonormal basis of L^2([0,1]), which is time-frequency localized, in the sense of Donoho-Stark Theorem (1989). Our approach provides a unified setting in which to study the Stockwell transform (associated to different admissible windows) and its orthogonal decomposition. Finally, we introduce a fast -- O(N log N) -- algorithm to compute the Stockwell coefficients for an admissible window. Our algorithm extends the one proposed by Y. Wang and J. Orchard (2009).Comment: 27 pages, 6 figure

    Holomorphic line bundles over domains in Cousin groups and the algebraic dimension of OT-manifolds

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    In this paper we extend results due to Vogt on line bundles over Cousin groups to the case of domains stable by the maximal compact subgroup. This is used in the sequel to show that the algebraic dimension of OT-manifolds is zero. In the last part we establish that certain Cousin groups, in particular those arising from the construction of OT-manifolds, have finite-dimensional irregularity.Comment: 13 page

    The appraisal of buildable land for property taxation in the adopted general municipal plan

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    In Italy, tax base for "Imposta Municipale Unica" related to the building area -made such by General Plan or its General Variation adopted but not approved - is the value (of the same building area) depending on the building potential of prediction even if not immediately exercisable. However, the building rights can be exercised only after: (i) the final approval of the General Plan/General Variation; (ii) the approval of the Implementation Plan required by Law; (iii) the issuance of certificates of permission building. This has produced in recent years several disputes between owners and local governments; the law did not give univocal solutions: today (2015) there is a conflict of case law relating to consider this areas absolutely as building areas, as well as it isn't defined what estimating procedures should be used. In this paper, through the application of a model of financial mathematics, an approach that overcomes the conflict law related to the appraisal of the building areas included inGeneral Plans/General Variation adopted but not yet approved, is proposed: the appraisal will be performed in relation to the time and variables between the time of the appraisal and the time (alleged) for the completion of the administrative procedure for obtaining authorizations to build

    Frontiers of Adaptive Design, Synthetic Biology and Growing Skins for Ephemeral Hybrid Structures

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    The history of membranes is one of adaptation, from the development in living organisms to man-made versions, with a great variety of uses in temporary design: clothing, building, packaging, etc. Being versatile and simple to integrate, membranes have a strong sustainability potential, through an essential use of material resources and multifunctional design, representing one of the purest cases where “design follows function.” The introduction of new engineered materials and techniques, combined with a growing interest for Nature-inspired technologies are progressively merging man-made artifacts and biological processes with a high potential for innovation. This chapter introduces, through a number of examples, the broad variety of hybrid membranes in the contest of experimental Design, Art and Architecture, categorized following two different stages of biology-inspired approach with the aim of identifying potential developments. Biomimicry, is founded on the adoption of practices from nature in architecture though imitation: solutions are observed on a morphological, structural or procedural level and copied to design everything from nanoscale materials to building technologies. Synthetic biology relies on hybrid procedures mixing natural and synthetic materials and processes

    Boundary value problems with Atiyah-Patodi-Singer type conditions and spectral triples

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    We study realizations of pseudodifferential operators acting on sections of vector-bundles on a smooth, compact manifold with boundary, subject to conditions of Atiyah-Patodi-Singer type. Ellipticity and Fredholm property, compositions, adjoints and self-adjointness of such realizations are discussed. We construct regular spectral triples (A,H,D)(\mathcal{A},\mathcal{H},\mathcal{D}) for manifolds with boundary of arbitrary dimension, where H\mathcal{H} is the space of square integrable sections. Starting out from Dirac operators with APS-conditions, these triples are even in case of even dimensional manifolds; we show that the closure of A\mathcal{A} in L(H)\mathscr{L}(\mathcal{H}) coincides with the continuous functions on the manifold being constant on each connected component of the boundary.Comment: 27 pages, to appear in Journal of Noncommutative Geometr

    Treatment of realistic tidal field in Monte Carlo simulations of star clusters

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    We present a new implementation of the Monte Carlo method to simulate the evolution of star clusters. The major improvement with respect to the previously developed codes is the treatment of the external tidal field taking into account for both the loss of stars from the cluster boundary and the disk/bulge shocks. We provide recipes to handle with eccentric orbits in complex galactic potentials. The first calculations for stellar systems containing 21000 and 42000 equal-mass particles show good agreement with direct N-body simulations in terms of the evolution of both the enclosed mass and the Lagrangian radii provided that the mass-loss rate does not exceed a critical value.Comment: 17 pages, 13 figures, accepted for publication by MNRA
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