Search results for "pac"
showing 10 items of 28794 documents
Governance della crisi e importanza del territorio per lo sviluppo regionale
2012
The aim of this paper is a reflection on the role of space in the processes of economic change. Starting in the United States the financial and economic crisis infected Europe after 2007. A wider debate on the current differential role of governments in the U.S. and Europe in addressing the crisis has emerged. The bailout programs in the U.S. have made reference to a unitary and homogeneous reference frame in the presence of a central bank whose broad mandate includes development goals. Europe, instead, has shown a different scenario and the same financial integration project depends on the complex relationship between individuals and the community, national sovereignty and increasingly bin…
On the effects of suitably designed space microstructures in the propagation of waves in time modulated composites
2023
In the one-dimensional case, the amplitude of a pulse that propagates in a homogeneous material whose properties are instantaneously changed in time will undergo an exponential increase due to the interference between the reflected and transmitted pulses generated at each sudden switch. Here, we resolve the issue by designing suitable reciprocal PT-symmetric space-time microstructures so that the interference between the scattered waves is such that the overall amplitude of the wave will be constant in time in each constituent material. Remarkably, for the geometries proposed here, a pulse will propagate with constant amplitude regardless of the impedance between the constituent materials,…
Nonparametric intensity estimation in space-time point processes and application to seismological problems
2008
Missing Data in Space-time: Long Gaps Imputation Based On Functional Data Analysis
2017
High dimensional data with spatio-temporal structures are of great interest in many elds of research, but their exhibited complexity leads to practical issues when formulating statistical models. Functional data analysis through smoothing methods is a proper framework for incorporating space-time structures: extending the basic methodology to the multivariate spatio-temporal setting, we refer to Generalized Additive Models for estimating functional data taking the spatial and temporal dependences into account, and to Functional Principal Component Analysis as a classical dimension reduction technique to cope with the high dimensionality and with the number of estimated eects. Since spatial …
Exploring mobilities in time and space
2013
Spazio e lingua nella 'costruzione' greca dell'identità etnica. Alcune osservazioni a partire da Erodoto
2018
The paper aims to offer an account of some representative opinions of ancient Greeks about the role of the space, conceived in its geographical/environmental value, in which a certain population lives, as well as of the language spoken by a population, in order to build historically the concept of Greek nation (to Hellenikón). The different positions expressed on these matters by Herodotus, Thucydides, Strabon and Pausanias are discussed, and the examination mostly concernes the ethnic and historical-linguistic aspects of the representation of the Dorians and Ionians.
Modelling flow and heat transfer in spacer-filled membrane distillation channels using open source CFD code
2013
Abstract A good understanding of the details of hydrodynamic and heat transport conditions and their impact on temperature polarisation and pressure drops is essential for optimum design of membrane distillation (MD) modules. To this end, the present work reports on initial progress in the development of a tool for 3D simulation of spacer-filled MD channels based on the open source CFD code library OpenFOAM. The paper discusses a number of modelling and implementation aspects including model geometry and computational domain, choice of boundary conditions, and discretisation schemes. The results pertaining to the effect of three different spacer types on the fluid dynamics and heat transfer…
Friction and Heat Transfer in Membrane Distillation Channels: An Experimental Study on Conventional and Novel Spacers
2022
The results of an experimental investigation on pressure drop and heat transfer in spacer-filled plane channels, which are representative of Membrane Distillation units, are presented and discussed. Local and mean heat transfer coefficients were obtained by using Thermochromic Liquid Crystals and Digital Image Processing. The performances of a novel spacer geometry, consisting of spheres that are connected by cylindrical rods, and are hereafter named spheres spacers, were compared with those of more conventional woven and overlapped spacers at equal values of the Reynolds number Re (in the range ~150 to ~2500), the pitch-to-channel height ratio, the flow attack angle and the thermal boundar…
Space-Time Forecasting of Seismic Events in Chile
2017
The aim of this work is to study the seismicity in Chile using the ETAS (epidemic type aftershock sequences) space‐time approach. The proposed ETAS model is estimated using a semi‐parametric technique taking into account the parametric and nonparametric components corresponding to the triggered and background seismicity, respectively. The model is then used to predict the temporal and spatial intensity of events for some areas of Chile where recent large earthquakes (with magnitude greater than 8.0 M) occurred.
Prekäre Räume
2020
Recent events in the Mediterranean call up for a radical questioning of our categories and representations. Sinking boats and emergency landings, reception policies and detention centres, crossings, deviations and refoulements symbolize an era when mobility is fatally related to security policies and new biopolitical regimes. Migrant bodies crossing the Mediterranean address a demand and a challenge that cultural geography is urged to accomplish. The aim of this paper is therefore to rethink spatiality in an ethical sense. Drawing on the philosophy of Emmanuel Lévinas and Judith Butler, we will try to imagine a new spatiality starting from bodies, displacements, and the complex open weave p…