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51.
Urban Computing is a branch of Pervasive Computing that investigates urban settings and everyday lifestyles. A large quantity of information to develop pervasive applications for urban environments is often already available, even if scattered and not integrated: maps, points of interest, user locations, traffic, pollution, and events are just a few examples of the digitalized information which we can access on the Web. Applications for mobile users that leverage such information are rapidly growing. In this article, we report our experience in addressing practical computational issues influencing the use of Geographic Information Systems and geospatial data from the standpoint of semantics and pervasive computing. We refer to the early achievements of the LarKC project, in which we developed an Urban Computing demonstrator. We highlight the positive sides of our experience and we discuss open issues and possible advances. 相似文献
52.
Biagio Giaccio Roberto Isaia Francesco G. Fedele Emanuele Di Canzio John Hoffecker Annamaria Ronchitelli Andrey A. Sinitsyn Mikhail Anikovich Sergey N. Lisitsyn Vasil V. Popov 《Journal of Volcanology and Geothermal Research》2008
Tephra layers from archaeological sites in southern Italy and eastern Europe stratigraphically associated with cultural levels containing Early Upper Palaeolithic industry were analysed. The results confirm the occurrence of the Campanian Ignimbrite tephra (CI; ca. 40 cal ka BP) at Castelcivita Cave (southern Italy), Temnata Cave (Bulgaria) and in the Kostenki–Borshchevo area of the Russian Plain. This tephra, originated from the largest eruption of the Phlegrean Field caldera, represents the widest volcanic deposit and one of the most important temporal/stratigraphic markers of western Eurasia. At Paglicci Cave and lesser sites in the Apulia region we recognise a chemically and texturally different tephra, which lithologically, chronologically and chemically matches the physical and chemical characteristics of the Plinian eruption of Codola; a poorly known Late Pleistocene explosive event from the Neapolitan volcanoes, likely Somma–Vesuvius. For this latter, we propose a preliminary age estimate of ca. 33 cal ka BP and a correlation to the widespread C-10 marine tephra of the central Mediterranean. The stratigraphic position of both CI and Codola tephra layers at Castelcivita and Paglicci help date the first and the last documented appearance of Early Upper Palaeolithic industries of southern Italy to ca. 41–40 and 33 cal ka BP, respectively, or between two interstadial oscillations of the Monticchio pollen record – to which the CI and Codola tephras are physically correlated – corresponding to the Greenland interstadials 10–9 and 5. In eastern Europe, the stratigraphic and chronometric data seem to indicate an earlier appearance of the Early Upper Palaeolithic industries, which would predate of two millennia at least the overlying CI tephra. The tephrostratigraphic correlation indicates that in both regions the innovations connected with the so-called Early Upper Palaeolithic – encompassing subsistence strategy and stone tool technology – appeared and evolved during one of the most unstable climatic phases of the Last Glacial period. On this basis, the marked environmental unpredictability characterising this time-span is seen as a potential ecological factor involved in the cultural changes observed. 相似文献
53.
Giuseppe Cello Roberto Gambini Stefano Mazzoli Andrew Read Emanuele Tondi Vittorio Zucconi 《Journal of Geodynamics》2000,29(3-5)
Systematic in situ analysis of active fault zones in Val d’Agri (southern Italy) suggests that the acquisition of quantitative data on fault-related structural discontinuities is fundamental for (1) discriminating between the latter and older regional features, (2) defining the architecture and related permeability structure of faults, and (3) performing simple statistics in order to evaluate the validity range within which fault characteristics may be considered to be fractals. This type of information can be integrated with regional seismotectonic analysis in order to asses the present-day conditions of deformation characterising the area, and to constrain the possible kinematics of the seismogenic structures controlling earthquake activity in this sector of the southern Apennines. The results of our study are also of interest for modelling earthquake sources, since a knowledge of the permeability structure and scaling properties of a faulted rock volume is potentially relevant for simulating the time and space dependent behaviour of fault zones during a seismic cycle. 相似文献
54.
A detailed numerical simulation of the ground motion and a site response analysis for two towns in the Marche Region (Treia
and Cagli) is carried out on the basis of structural models deduced from available geological and geophysical data. In both
cases, the reference event is an M = 5.7 earthquake associated with a normal fault located beneath each town. The ground motion is computed using the 2D spectral
element method (SPEM 2D). The method solves the propagation of the seismic field through complex geological structures and
enables an estimate of the effects of deep crustal structure, superficial geology, and topography on ground motion. Numerical
simulations of the seismic field are performed along 2D vertical planes containing the seismic source. Strong ground motion
has not been yet recorded in the two towns; therefore, the numerical simulation of ground motion represents a way to overcome
the lack of instrumental data. The simulations carried out for Treia show that ground motion is influenced by both source
mechanism and effects due to propagation through the geological structure, while ground motion in Cagli features strong local
effects, caused by the presence of alluvial deposits under a large area of the town. 相似文献
55.
Palma Massimiliano Iacono Roberto Sannino Gianmaria Bargagli Andrea Carillo Adriana Fekete Balazs M. Lombardi Emanuele Napolitano Ernesto Pisacane Giovanna Struglia Maria Vittoria 《Ocean Dynamics》2020,70(7):935-963
Ocean Dynamics - The tides in the Mediterranean Sea are generally weaker than in other regions of the world ocean, but are locally intensified in passages with complex bathymetry, such as the... 相似文献
56.
Jorge G. Lozano Donaldo M. Bran Federica Donda Emanuele Lodolo Federico D. Esteban Alejandro Tassone 《第四纪科学杂志》2021,36(2):273-287
At ~20 ka bp , lakes Yehuin, Chepelmut and Fagnano constituted a single, large water body in the central part of Isla Grande de Tierra del Fuego (southernmost Patagonia). The evolutionary history of this lake, known as ‘Palaeolago Fueguino’, was probably controlled by the advances, stillstands and retreats of the ‘Fagnano Palaeoglacier’, an outlet glacier that flowed eastward from the Darwin Cordillera ice sheet. A detailed analysis of high-resolution seismic reflection profiles acquired within the three lakes has allowed the identification and correlation of seven unconformities within the lacustrine sedimentary infill, three seismostratigraphic sequences in Lago Fagnano and four in Lago Yehuin. A seismic stratigraphic correlation between these sequences suggests that these basins formerly constituted a single, large lacustrine body. A lake-level curve of the evolutionary stages of each lake, derived from the seismostratigraphic analysis of the sedimentary infill is proposed here, representing a 17.5 ka-long record. It was further integrated with the glacial record of the advances and retreats of the Fagnano Palaeoglacier. This study has implications for interpreting the sedimentary history of lake basins in glaciated mountain ranges. 相似文献
57.
58.
In this paper we argue that the financial provisions of the Copenhagen Accord, if used primarily to mitigate greenhouse gas (GHGs) emissions, could compensate the lack of more energetic action on the domestic mitigation side. In order to maximize the mitigation potential, the Copenhagen Green Climate Fund (CGCF) should be transformed into the International Bank for Emissions Allowance Acquisition (IBEAA) envisaged by Bradford (2008). We estimate that 50 percent of the CGCF in 2020 (50 US billions) could finance from 2.1 to 3.3?Gt CO2-eq emission reductions, depending on the domestic mitigation effort of Annex I and Non-Annex I countries. We construct a matrix that shows the level of GHGs emissions in 2020 under all possible combinations of abatement pledges and international mitigation financing, thus highlighting a rich set of options to reach the same level of GHGs emissions in 2020. 相似文献
59.
Laura Greggio Alvio Renzini Emanuele Daddi 《Monthly notices of the Royal Astronomical Society》2008,388(2):829-837
Following an episode of star formation, Type Ia supernova events occur over an extended period of time, following a distribution of delay times (DDT). We critically discuss some empirically based DDT functions that have been proposed in recent years, some favouring very early (prompt) events, other very late (tardy) ones, and therefore being mutually exclusive. We point out that in both the cases the derived DDT functions are affected by dubious assumptions, and therefore there is currently no ground for claiming either a DDT strongly peaked at early times, or at late ones. Theoretical DDT functions are known to accommodate both prompt as well as late SN Ia events, and can account for all available observational constraints. Recent observational evidence exist that both single and double degenerate precursors may be able of producing SN Ia events. We then explore on the basis of plausible theoretical models the possible variation with cosmic time of the mix between the events produced by the two different channels, which, in principle, could lead to systematic effects on the SN Ia properties with redshift. 相似文献
60.
Emanuela Molinaroli Alessandro Sarretta Christian Ferrarin Emanuele Masiero Antonietta Specchiulli Stefano Guerzoni 《Journal of Earth System Science》2014,123(5):1097-1114
Integrated classification maps were produced by combining sediment grain-size and hydrological data (water renewal time, WRT) from two Mediterranean lagoons, Lesina (LL) and Varano (LV), Italy. The geophysical characteristics of the two basins, derived from detailed bathymetric charts, are quite distinct: ~30% of LL (mean depth ~1 m) but only 3% of LV (mean depth ~3 m) is shallower than 1 m. The sediments of both lagoons are mainly composed of mud (~80%). A detailed multivariate analysis of grain-size data by EntropyMax classified the lagoon beds of LL and LV into five sedimentary facies. WRT data, computed by a hydrodynamic model, indicated different hydrological conditions in the two lagoons: LL showed a sharp west–east gradient, with a basin-wide average of ~190 days, whilst LV showed a fairly uniform distribution and a higher basin-wide average (~260 days). The distribution of sedimentary facies and water renewal times were combined in a composite map representing the distribution of environmental patterns. The approach outlined in this study can be used to improve zonation schemes by providing a hydromorphological perspective on transitional and coastal environments. 相似文献