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61.
Eugenio Trumpy Gianpaolo Coro Adele Manzella Pasquale Pagano Donatella Castelli Philippe Calcagno 《International Journal of Digital Earth》2016,9(5):499-519
Geothermal data are published using different IT services, formats and content representations, and can refer to both regional and global scale information. Geothermal stakeholders search for information with different aims. E-Infrastructures are collaborative platforms that address this diversity of aims and data representations. In this paper, we present a prototype for a European Geothermal Information Platform that uses INSPIRE recommendations and an e-Infrastructure (D4Science) to collect, aggregate and share data sets from different European data contributors, thus enabling stakeholders to retrieve and process a large amount of data. Our system merges segmented and national realities into one common framework. We demonstrate our approach by describing a platform that collects data from Italian, French, Hungarian, Swiss and Icelandic geothermal data providers. 相似文献
62.
Jack Lorell George H. Born Edward J. Christensen Pasquale B. Esposito J. Frank Jordan Philip A. Laing William L. Sjogren Sun K. Wong Robert D. Reasenberg Irwin I. Shapiro Gary L. Slater 《Icarus》1973,18(2):304-316
Further reduction of Doppler tracking data from Mariner 9 confirms our earlier conclusion that the gravity field of Mars is considerably rougher than the fields of either the Earth or the Moon. The largest positive gravity anomaly uncovered is in the Tharsis region which is also topographically high and geologically unusual. The best determined coefficients of the harmonic expansion of the gravitational potential are: J2 = (1.96 ± 10.01) × 10?3 ; C22 = ?(5.1 ± 0.2) × 10?5; and S22 = (3.4 ± 0.2) × 10?5. The other coefficients have not been well determined on an individual basis, but the ensemble yields a useful model for the gravity field for all longitudes in the vicinity of 23° South latitude which corresponds to the periapse position for the orbiter.The value obtained for the inverse mass of Mars (3 098 720 ± 70 M⊙?1) is in good agreement with prior determinations from Mariner flyby trajectories. The direction found for the rotational pole of Mars, referred to the mean equinox and equator of 1950.0, is characterized by α = 317°.3 ± 0°.2, δ = 52°.7 ± 0°.2. This result is in excellent agreement with Sinclair's recent value, determined from earth-based observations of Mars' satellites, but differs by about 0°.5 from the previously accepted value. Other important physical constants that have either been refined or confirmed by the Mariner 9 data include: (i) the dynamical flattening, f = (5.24 ± 0.02) × 10?3; (ii) the maximum principal moment of inertia, C = (0.375 ± 0.006) MR2; and (iii) the period of precession of Mars' pole, P ? (1.73 ± 0.03) × 105 yr, corresponding to a rate of 7.4 sec of arc per yr. 相似文献
63.
Celestial Mechanics and Dynamical Astronomy - We are dealing with the averaged model used to study the secular effects in the motion of a body of the negligible mass in the context of a spatial... 相似文献
64.
65.
R. Maresca L. Nardone G. Pasquale F. Pinto F. Bianco 《Pure and Applied Geophysics》2012,169(7):1173-1188
The effects of surface geology on ground motion provide an important tool in seismic hazard studies. It is well known that the presence of soft sediments can cause amplification of the ground motion at the surface, particularly when there is a sharp impedance contrast at shallow depth. The town of Avellino is located in an area characterised by high seismicity in Italy, about 30?km from the epicentre of the 23 November 1980, Irpinia earthquake (M?=?6.9). No earthquake recordings are available in the area. The local geology is characterised by strong heterogeneity, with impedance contrasts at depth. We present the results from seismic noise measurements carried out in the urban area of Avellino to evaluate the effects of local geology on the seismic ground motion. We computed the horizontal-to-vertical (H/V) noise spectral ratios at 16 selected sites in this urban area for which drilling data are available within the first 40?m of depth. A Rayleigh wave inversion technique using the peak frequencies of the noise H/V spectral ratios is then presented for estimating Vs models, assuming that the thicknesses of the shallow soil layers are known. The results show a good correspondence between experimental and theoretical peak frequencies, which are interpreted in terms of sediment resonance. For one site, which is characterised by a broad peak in the horizontal-to-vertical spectral-ratio curve, simple one-dimensional modelling is not representative of the resonance effects. Consistent variations in peak amplitudes are seen among the sites. A site classification based on shear-wave velocity characteristics, in terms of Vs30, cannot explain these data. The differences observed are better correlated to the impedance contrast between the sediments and basement. A more detailed investigation of the physical parameters of the subsoil structure, together with earthquake data, are desirable for future research, to confirm these data in terms of site response. 相似文献
66.
Loreto Rossi M. Letizia Costantini Pasquale Carlino Antonella di Lascio David Rossi 《Aquatic Sciences - Research Across Boundaries》2010,72(2):227-236
The high numbers of primary producers represent multiple sources of organic matter accumulating onto lake bottoms. The difficulty
of distinguishing the relative contribution to the mixture presents considerable challenges to the analysis of these organic
deposits. In this study, dual-stable isotope analysis and IsoSource model were used to identify allochthonous and autochthonous
components of detritus deposits (Particulate Organic Matter: POM) at two different bottom slope sites of a volcanic lake (lake
Bracciano). Experiments were carried out to calibrate IsoSource on constructed plant mixtures and assess changes in isotope
ratios during plant decomposition. IsoSource satisfactorily discriminated the constructed mixture sources with a few exceptions.
Changes in isotopic enrichment during decomposition were low, and thus did not represent a confounding variable in the isotopic
analysis. By contrast, chemical and geological differences of the study sites were associated with differences in plant δ13C and δ15N values (more than 2‰ within single plant species). At both sites, the isotopic signals of POM fell between polygons delineated
by source end members with an evident shift of δ13C toward allochthonous sources. POM amount and diversity were greater at the flatter bottom site, where allochthonous contributions
were larger than at the other site. In particular, IsoSource ranked species contributions as follows: A. glutinosa > P. australis > A. donax > S. alba > P. nigra > the benthic macroalga Chara sp. at the first site, and A. glutinosa > P. nigra > the aquatic macrophyte C. demersum at the latter. The composition of littoral POM was determined by allochthonous sources in proportion to their relative abundances
(as percent land cover) with differences between sites due to bottom slope. 相似文献
67.
A modal procedure for non-linear analysis of multistorey structures with high-damping base-isolation systems was proposed. Two different isolation devices were considered in the analysis: an high-damping laminated rubber bearing and a lead-rubber bearing. Starting from deformational properties verified by tests, the isolation systems were characterized using three different analytical models (an Elastic Viscous, a Bilinear Hysteretic and a Wen's Model) with parameters depending from maximum lateral strain. After non-linear modelling of isolation and lateral-force-resisting systems, the effects of material non-linearities were considered as pseudo-forces applied to the equivalent linear system (Pseudo-Force Method) and the formally linearized equations of motion were uncoupled by the transformation defined by the complex mode shapes. The modal responses were finally obtained with an extension of Nigam–Jennings technique to non-linear and non-classically damped systems, in conjunction with an iterative technique searching for non-linear contributions satisfying equations of motion and constitutive laws. Since the properties of the isolated structure usually change with maximun lateral strain of isolation bearings, the integration of a new set of governing equations was required for each design-displacement value. The procedure proposed was described in detail and then applied for the determination of modal and total seismic responses in some real cases. At first, a very good agreement between non-linear responses obtained with the proposed mode superposition and with a direct integration method was observed. Then a comparison of results obtained with the three different analytical models of the isolation bearings was carried out. At last, the exact modal response obtained with analytical models depending from the design displacement of the isolation bearings was compared with two different approximated solutions, evaluated using mode shapes and isolation properties, respectively, calculated under simplified hypothesis.© 1998 John Wiley & Sons, Ltd. 相似文献
68.
Pellegrino Conte Cristina AbbateAndrea Baglieri Michéle NègreClaudio De Pasquale Giuseppe AlonzoMara Gennari 《Organic Geochemistry》2011,42(8):972-977
Dissolved organic matter (DOM) is a very important environmental constituent due to its role in controlling factors for soil formation, mineral weathering and pollutant transport in the environment. Prediction of DOM physical-chemical properties is achieved by studying its chemical structure and spatial conformation. In the present study, dissolved organic matter extracted from compost obtained from the organic fraction of urban wastes (DOM-P) has been analysed by FT-IR, CPMAS 13C NMR spectroscopy and 1H T1 NMR relaxometry with fast field cycling (FFC) setup. While the first two spectroscopic techniques revealed the chemical changes of dissolved organic matter after adsorption either on kaolinite (DOM-K) or montmorillonite (DOM-S), the latter permitted the evaluation of the conformational variations as assessed by longitudinal relaxation time (T1) distribution at the fixed magnetic field of 500 mT. Alterations of T1 distributions from DOM-P to DOM-K and DOM-S were attributed to a decreasing molecular complexity following DOM-P adsorption on the clay minerals. This study applied for the first time solid state 1H T1 NMR relaxometry to dissolved organic matter from compost obtained from the organic fraction of urban wastes and revealed that this technique is very promising for studying environmentally relevant natural organic systems. 相似文献
69.
Alessandro Mondanaro Mirko Di Febbraro Marina Melchionna Francesco Carotenuto Silvia Castiglione Carmela Serio Simone Danisi Lorenzo Rook Jose Alexandre F. Diniz‐Filho Pasquale Raia 《Boreas: An International Journal of Quaternary Research》2019,48(3):605-615
Cave bears (Ursus spelaeus) are an iconic component of the European late Quaternary Ice Age megafauna. Recent demographic analyses based on cave bear mtDNA sequences and refined radiocarbon dating indicate that cave bear population size and genetic diversity started to decline some 50 kilo years ago (kya). Hence, neither the coldest phase of the last glaciation (started some 24 kya), nor the colonization of Europe by Palaeolithic hunters (started some 45 kya) coincides with the beginning of population decline. Here, we reconstructed cave bear climatic niche evolution through time. Then, we performed spatially explicit population viability analyses to assess cave bear demographics through time in response to climatic changes, human effects on bear survival and their combination. We found that climate change was responsible for a 10‐fold decrease in cave bear population size after 40 kya. However, climate change on its own could not explain U. spelaeus extinction at 24 kya. Additional negative effects consistent with human population expansion are required to explain both U. spelaeus' retreat from eastern Europe since 40 kya and its final extinction. 相似文献
70.
FLaIR and SUSHI: two mathematical models for early warning of landslides induced by rainfall 总被引:8,自引:7,他引:1
The development of Early Warning Systems in recent years has assumed an increasingly important role in landslide risk mitigation.
In this context, the main topic is the relationship between rainfall and the incidence of landslides. In this paper, we focus
our attention on the analysis of mathematical models capable of simulating triggering conditions. These fall into two broad
categories: hydrological models and complete models. Generally, hydrological models comprise simple empirical relationships
linking antecedent precipitation to the time that the landslide occurs; the latter consist of more complex expressions that
take several components into account, including specific site conditions, mechanical, hydraulic and physical soil properties,
local seepage conditions, and the contribution of these to soil strength. In a review of the most important models proposed
in the technical and international literature, we have outlined their most meaningful and salient aspects. In particular,
the Forecasting of Landslides Induced by Rainfall (FLaIR) and the Saturated Unsaturated Simulation for Hillslope Instability
(SUSHI) models, developed by the authors, are discussed. FLaIR is a hydrological model based on the identification of a mobility
function dependent on landslide characteristics and antecedent rainfall, correlated to the probability of a slide occurring.
SUSHI is a complete model for describing hydraulic phenomena at slope scale, incorporating Darcian saturated flow, with particular
emphasis on spatial–temporal changes in subsoil pore pressure. It comprises a hydraulic module for analysing the circulation
of water from rainfall infiltration in saturated and nonsaturated layers in non-stationary conditions and a geotechnical slope
stability module based on Limit Equilibrium Methods. The paper also includes some examples of these models’ applications in
the framework of early warning systems in Italy. 相似文献