904 research outputs found

    Optimal Spectral Domain Selection for Maximizing Archaeological Signatures: Italy Case Studies

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    Different landscape elements, including archaeological remains, can be automatically classified when their spectral characteristics are different, but major difficulties occur when extracting and classifying archaeological spectral features, as archaeological remains do not have unique shape or spectral characteristics. The spectral anomaly characteristics due to buried remains depend strongly on vegetation cover and/or soil types, which can make feature extraction more complicated. For crop areas, such as the test sites selected for this study, soil and moisture changes within near-surface archaeological deposits can influence surface vegetation patterns creating spectral anomalies of various kinds. In this context, this paper analyzes the usefulness of hyperspectral imagery, in the 0.4 to 12.8 μm spectral region, to identify the optimal spectral range for archaeological prospection as a function of the dominant land cover. MIVIS airborne hyperspectral imagery acquired in five different archaeological areas located in Italy has been used. Within these archaeological areas, 97 test sites with homogenous land cover and characterized by a statistically significant number of pixels related to the buried remains have been selected. The archaeological detection potential for all MIVIS bands has been assessed by applying a Separability Index on each spectral anomaly-background system of the test sites. A scatterplot analysis of the SI values vs. the dominant land cover fractional abundances, as retrieved by spectral mixture analysis, was performed to derive the optimal spectral ranges maximizing the archaeological detection. This work demonstrates that whenever we know the dominant land cover fractional abundances in archaeological sites, we can a priori select the optimal spectral range to improve the efficiency of archaeological observations performed by remote sensing data

    Suitability of CASI and ATM airborne remote sensing data for archaeological subsurface structure detection under different land cover: the Arpi case study (Italy)

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    In this paper multi-sensor airborne remote sensing has been applied to the Arpi archaeological area of southern Italy to assess its suitability for detecting and locating subsurface archaeological structures and to delineate subsurface remains beyond the current limits of ground geophysical data. To this aim, the capability of CASI and ATM reflectances in the VIS-NIR spectral range and the ATM apparent thermal inertia for subsurface archaeological prospection have been assessed at different sites of the Arpi archaeological area. First, linear spectral mixture analysis has been applied to CASI and ATM images to retrieve the dominant land cover for the selected subsurface structures, and then, the spectral bands most effective for the archaeological buried structure detection as a function of the land cover characteristics have been evaluated. The results reveal that multi/hyperspectral airborne remote sensing data can represent an effective and rapid tool to detect subsurface structures within different land cover contexts. Therefore, the proposed methodology can be used to perform a preliminary analysis of those areas where large cultural heritage assets occur by prioritizing and localizing the sites where to apply archaeological prospection

    Relations between morphological settings and vegetation covers in a medium relief landscape of Central Italy

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    Morphometric units and vegetation classes were determined by applying two classification methods to the Soratte Mount area, a medium relief structure within the Italian Latium region. The study aims at defining the relationships between vegetation and landform types and highlighting the main morphological characteristics within examined land cover classes. These were the result of the application of a supervised classification method to the first 28 (VIS-NIR) bands of the airborne MIVIS data collected within an extensive survey campaign over Rome Province. The analysis was supported by photo-interpretation of peculiar MIVIS band combinations and by data acquired during field surveys and from a pre-existing vegetation map. The morphometric data were obtained by processing a raster DEM created from topographic maps. These data were processed by means of a new morphometric classification method based on the statistical multivariate investigation of local topographic gradients, calculated along the 8 azimuth directions of each pixel neighbourhood. Such approach quickly estimates the spatial distribution of different types of homogeneous terrain units, emphasizing the impact of erosional and tectonic processes on the overall relief. Mutual relations between morphometric units and vegetation types were assessed by performing a correspondence analysis between the results of the two classifications

    Multiscale integration of satellite, airborne and field data for Mediterranean vegetation studies in the natural area of the Castelporziano Estate (Rome)

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    A new experimental approach to land analysis has recently been developed, based on the integration of information acquired on different scales; it enables the structure and the functionality of the vegetation in natural ecosystems to be analysed. This research aims at assessing the potentiality of the experimental approach by the integration of airborne and satellite remotely sensed data with ground measurements of structural parameters. In July 1999 a joint campaign for the acquisition of airborne (MIVIS, spatial resolution 3 in) and satellite remotely sensed data (Landsat 5TM, spatial resolution 30 in) and measures taken at ground (PAI), was deployed in the Presidential Estate at Castelporziano (Rome, Italy). The spectral signatures of the main vegetational types of the Estate were examined and the PAI were related to NDVI values, calculated by means of satellite and airborne images. The adopted approach enabled PAI maps to be produced. The linear relation between measured PAI and estimated PAI showed a higher coefficient of determination when the MIVIS data were used. The sensor high spectral resolution has moreover allowed to better describe the structural characteristics of the main plant typologies at Castelporziano Estate

    Aerosol Optical Retrieval and Surface Reflectance from Airborne Remote Sensing Data over Land

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    Quantitative analysis of atmospheric optical properties and surface reflectance can be performed by applying radiative transfer theory in the Atmosphere-Earth coupled system, for the atmospheric correction of hyperspectral remote sensing data. This paper describes a new physically-based algorithm to retrieve the aerosol optical thickness at 550nm (τ550) and the surface reflectance (ρ) from airborne acquired data in the atmospheric window of the Visible and Near-Infrared (VNIR) range. The algorithm is realized in two modules. Module A retrieves τ550 with a minimization algorithm, then Module B retrieves the surface reflectance ρ for each pixel of the image. The method was tested on five remote sensing images acquired by an airborne sensor under different geometric conditions to evaluate the reliability of the method. The results, τ550 and ρ, retrieved from each image were validated with field data contemporaneously acquired by a sun-sky radiometer and a spectroradiometer, respectively. Good correlation index, r, and low root mean square deviations, RMSD, were obtained for the τ550 retrieved by Module A (r2 = 0.75, RMSD = 0.08) and the ρ retrieved by Module B (r2 ≤ 0.9, RMSD ≤ 0.003). Overall, the results are encouraging, indicating that the method is reliable for optical atmospheric studies and the atmospheric correction of airborne hyperspectral images. The method does not require additional at-ground measurements about at-ground reflectance of the reference pixel and aerosol optical thickness

    Sociopolitical consequences of COVID-19 in the Americas, Europe, and Asia: A multilevel, multicountry investigation of risk perceptions and support for antidemocratic practices

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    Although different social crises may eventually favor undemocratic and authoritarian forms of governance, at some point, such antidemocratic practices require the support of a significant part of the population to be implemented. The present research investigates how and whether the COVID-19 pandemic might have favoured greater support for antidemocratic governmental practices, on the premise of regaining control and security. Using data from 17 countries (N = 4364) and national-level indicators (i.e., real number of contagions and deaths, and sociopolitical indicators), we test how the risk of contagion and death from COVID-19, along with personal orientations (i.e., social dominance orientation [SDO], right-wing authoritarianism [RWA], and perceived anomie) motivate authoritarian and antidemocratic practices. Results from multilevel models indicate that risk perception and perceptions of political instability predict a wish for stronger leadership, agreement with martial law, and support for a controlling government especially when SDO and RWA are high, while more egalitarian and less conservative people agree less with these authoritarian measures in spite of the levels of risk perception. We discuss the implications for these findings for future research on similar but also dissimilar external events (natural disasters, war, or terror incidents) and the consequences for societies with higher authoritarian tendencies.Fil: Pizarro, José J.. Universidad Católica del Norte; Chile. Universidad del País Vasco; EspañaFil: Cakal, Huseyin. Keele University; Reino UnidoFil: Méndez, Lander. Universidad del País Vasco; EspañaFil: Zumeta, Larraitz N.. Universidad del País Vasco; EspañaFil: Gracia-Leiva, Marcela. Universidad del País Vasco; EspañaFil: Basabe, Nekane. Universidad del País Vasco; EspañaFil: Navarro-Carrillo, Ginés. Universidad de Jaén; EspañaFil: Cazan, Ana Maria. Transilvania University of Brasov; RumaniaFil: Keshavarzi, Saeed. Independent Researcher; IránFil: López López, Wilson. Pontificia Universidad Javeriana; ColombiaFil: Yahiiaiev, Illia. Taras Shevchenko National University of Kyiv; UcraniaFil: Alzugaray Ponce, Carolina. Universidad Santo Tomas; ChileFil: Villagrán, Loreto. Universidad de Concepción; ChileFil: Moyano Díaz, Emilio. Universidad de Talca; ChileFil: Petrović, Nebojša. University of Belgrade; SerbiaFil: Mathias, Anderson. Universidad Autonoma de Coahuila; MéxicoFil: Techio, Elza M.. Universidade Federal da Bahia; BrasilFil: Wlodarczyk, Anna. Universidad Católica del Norte; ChileFil: Alfaro-Beracoechea, Laura. Universidad de Guadalajara; MéxicoFil: Ibarra, Manuel L.. Universidad Nacional Autónoma de México; MéxicoFil: Michael, Andreas. University of Cyprus; ChipreFil: Mhaskar, Sumeet. O.p. Jindal Global University; IndiaFil: Martínez Zelaya, Gonzalo. Universidad Viña del Mar; ChileFil: Bilbao, Marian. Universidad Alberto Hurtado; ChileFil: Delfino, Gisela Isabel. Universidad Pontificia Comillas; España. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Carvalho, Catarina L.. Universidad de Porto; PortugalFil: Pinto, Isabel R.. Universidad de Porto; PortugalFil: Mohsin, Falak Zehra. Karachi School Of Business And Leadership; PakistánFil: Espinosa, Agustín. Pontificia Universidad Católica de Perú; PerúFil: Cueto, Rosa María. Pontificia Universidad Católica de Perú; PerúFil: Cavalli, Stefano. Scuola Universitaria Professionale Della Svizzera Italiana; ItaliaFil: da Costa, Silvia. Universidad de Zaragoza; EspañaFil: Amutio, Alberto. Universidad Andrés Bello; Chile. Universidad del País Vasco; EspañaFil: Alonso Arbiol, Itziar. Universidad del País Vasco; EspañaFil: Páez, Darío. Universidad Andrés Bello; Chil

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for direct stau production in events with two hadronic tau-leptons in root s=13 TeV pp collisions with the ATLAS detector

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    A search for the direct production of the supersymmetric partners ofτ-leptons (staus) in final stateswith two hadronically decayingτ-leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of139fb−1, recorded with the ATLAS detector at the LargeHadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected StandardModel background is observed. Limits are derived in scenarios of direct production of stau pairs with eachstau decaying into the stable lightest neutralino and oneτ-lepton in simplified models where the two staumass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidencelevel for a massless lightest neutralino

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

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    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV
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