1,720,965 research outputs found
A Grid Enabled Look-Up Table for Aerosol Optical Thickness Estimation on Coastal Water
No full textCoastal area represents one of the more delicate and complex relation between natural environment and human activities. Remote sensing, offering considerable understanding of the temporal dynamics of bio-physical factors at different scale, represents a solution for monitoring the ecosystem. In particular marine phenomena, i.e. Sea Surface Temperature, chlorophyll concentration etc. can be related to the sea color observed from satellites. However standard satellite products, such as chlorophyll concentrations maps calculated from MODlS data, are useful only for oceanic water and cannot be directly extended to coastal water. For coastal water quality evaluation, specific inversion procedures should be used. Some of these procedures are based on look-up table generation that are computational intensive. In this paper a Grid based approach is proposed for LUT generation. This approach, producing accurate estimation of Aerosol Optical Thickness, represents a useful system to give fast and accurate answers without demand large economic investments
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
Coastal Observation through Cosmo-SkyMed High-Resolution SAR Images
No full textThe study deals with the application and further improvement of an advanced Earth Observation system, named COSMO-Beach, developed for semi-automatic shoreline extraction and coastal morphology identification. The system exploits SAR Single-Look-Complex data acquired by the COSMO-SkyMed constellation, which is able to provide X-band images with a short revisiting time. The implemented procedures have been tested over a very popular beach in Apulia Region (Italy), affected by erosion problems induced by human activities. The outcomes of the COSMO-Beach system are presented and 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
Using multi-temporal interferometry and Sentinel-1 data to monitor ground instability hazards related to open-cast mining operations
No full textSurface mining represents the predominant mineral and coal exploitation method in Europe and worldwide. Different mining methods can be involved, but most often: open-cast (open-pit) mining; terrace mining; contour strip mining; quarrying. Although surface mining is considered safer than underground mining, ground instability hazards represent an ever-present concern and important problem limiting the mining operations (e.g., slope instability in high wall open-cast mines and quarries). However, given the often large extent of areas affected by surface mining and life span of mines (tens of years), long-term monitoring via traditional in-situ methods is typically impractical (economically and technically). Here we focus on the use of an advanced multi-temporal interferomery (MTI) and Sentinel-1 imagery for mapping and monitoring of ground instabilities in open-cast mines and adjacent areas. Open-cast mines represent a good target for MTI, because they are i) often very large (from few to tens of km2); ii) free of or covered by sparse vegetation; iii) require long-term regular monitoring, which can now rely on free of charge Sentinel-1 data from the European Space Agency. However, a cursory review of the recent literature (international journals) suggests that in comparison to applications to underground mines, MTI has been relatively little exploited to investigate ground instabilities related to surface mining. One reason for this is that some portions of open-cast mines can lack measurable radar targets due to rapid changes of ground surface caused by intense mining operations (e.g., overburden stripping, waste material damping). We argue that this limitation can now be mitigated by the higher frequency and regularity of acquisitions provided by Sentinel-1 (nominally every 6 days since October 2016). To illustrate the potential of MTI for detecting and monitoring ground instabilities induced by surface mining, we present case study example of the Belchatow mine (Poland), one of the largest brown coal open-cast operations in Europe (about 12 km long and 3 km wide). The Belchatow open-cast mine reaches the depth of 310 m and has been affected by a number of slope failures in the last few decades. The failures disrupted the mining operations, destroyed in part the mining machinery and resulted in high economic losses. In this study we assess the recent and current stability conditions in the mine area by exploiting several tens of medium resolution (~20 m) images acquired by Sentinel-1 since October 2014. Despite the local lack of information (areas affected by intensive surface disturbance due to ongoing mining operations), the MTI results provided a valuable synoptic overview of the ground instability/stability condition within and outside the active mine. Although it is not simple to provide short-term forewarning of the impeding slope failure on the basis of the surface displacement time series alone, our experience indicate that long-term, high frequency MTI measurements offer the following benefits: i) better anticipation of risk of failure over large areas and more rational design of ground-based monitoring networks; ii) better planning for maintenance and management of open-cast mines
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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