1,721,037 research outputs found
Estimating Urban Growth from Landsat 8 Data Using Post-classification and Albedo Change Analysis in GEE Environment
No full textUrban growth, defined as the increase of artificial surfaces in cities or towns, is now considered critical for the environmental impacts it can generate. Mapping and monitoring the soil sealing phenomenon provides researchers, planners and decision-makers with useful information for sustainable development. Moreover, Earth observation remote sensing images, such as medium-resolution Landsat data, is widely adopted for short to long term urban change analysis. The aim of this paper is to extract information on land consumption occurred on urban areas (period 2015–2023) from Landsat 8 data using GEE cloud platform. The territory of the municipality of Bitritto, in Apulia region (Italy), was chosen as the study site. To achieve the objective of this work, a change detection approach, including both “post-classification comparison” and “image differencing” methods, was applied. To classify Landsat 8 multispectral images into a binary scheme (“urban areas” and “non-urban areas”), a decision tree approach using STRed and SwiRed indices, NIR/SWIR2 ratio and NIR band was developed and implemented in GEE environment. The “image differencing” step was, instead, performed by subtracting two land surface albedo maps, obtained from winter Landsat 8 images, for the two reference years. A neighborhood filter to remove isolated “changed” pixels was also applied to improve the outcome. The results were promising (P.A. 85% and U.A. 77% for the “urban growth” category, with an O.A. of 92%) even though some misclassifications were identified, probably due to “mixed” pixels or to some spectral confusion among certain land cover classes
Lesioni del polso
No full textDefinire il percorso diagnostico e terapeutico delle fratture del radio distale, del carpo, delle lesioni tendinee e delle amputazioni del pols
Copernicus Geodatabase for Investigating Land Cover Changes at the European Scale
No full textCopernicus, the European initiative for monitoring the Earth, provides an extensive range of data types that allow consumers, public authorities, and scientists to get free, open, and comprehensive knowledge of the world. Therefore, it is recognized as one of the largest geodatabases storing a great deal of data provided by satellites and in-situ sensors, which are then processed to generate reliable and up-to-date information on a large number of pressing environmental and security concerns. As a result, it could be a valid option for examining the state of landscape and its evolution over time. More knowledge about land changes might assist in developing an effective strategy to tackle the soil sealing phenomena, which is largely caused by climate change and anthropogenic pressure and is being experienced by all European countries. Thus, this study examines how Copernicus earth observation data and geographical services might help with changes in terrain cover at the European level. The land cover change maps were evaluated after looking at all the data, when it was possible to perform this task, while in other cases, Google Earth Engine, a cloud platform designed by Google to manage large geographic data, was used to produce the maps. The benefits and drawbacks of the Copernicus platform have been examined. It proves to be a functional platform for achieving research goals, but it is insufficient for a global study because of the absence of data in many European cities and the low resolution of many of them
Integration of Copernicus Data and Services to Assess Local Aridity Conditions in the Apulian Context: The Case of Marina di Ginosa
No full textWater is a fundamental element for life on the Earth. Its availability, at a local scale, depends on the climate as well as on how it is managed and distributed for human use. Nowadays, water scarcity is a major concern in many parts of the world, also in relation to the possible effects of climate change and urbanization. The aim of this study is to integrate various Copernicus and other free and open data in order to calculate the main components of the water balance as defined by ISPRA’s BIGBANG procedure. The territory of a basin including the locality of Marina di Ginosa, in southern Italy, was chosen as study site. All the analyses were carried out in the Google Earth Engine cloud environment, where a proper JavaScript code was developed. The estimation made it possible to retrieve monthly maps of the hydrological variables from October 2015 to September 2018 at a geometric resolution of 10 m, and to assess local drought conditions by applying the FAO-UNEP aridity index. Even if this approach is affected by uncertainties owing to the schematic representation of the natural processes, it is a valuable tool for analyzing the spatial and temporal fluctuations of the water resource availability, especially in critical areas of southern Italy
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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