1,720,957 research outputs found
A Preliminary Study on the Detection of Glacial Lake Outburst Flood in Norway Using Sentinel 2 Imagery
No full textOver recent decades, glacier retreat has altered dynamics and increased hazards, such as glacial lake outburst floods (GLOFs), leading to severe downstream flooding. While GLOFs are typically detected through on-site monitoring, existing remote sensing methods primarily map glacial lakes, without identifying GLOF events. This paper proposes an unsupervised approach to detect GLOFs using Sentinel-2 image time series. We train a deep network to model non-draining lake time series, preventing them from appearing as anomalies when drained. The model, based on convolutional Long-Short-Term Memory and a 3D convolutional neural network, reconstructs non-draining lake time series. Inference errors reveal draining lakes. Preliminary experiments on Norwegian glacial lakes show promising results for automated GLOF detection
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Assessing 30 years of coastline dynamics in Vietnam using the Landsat archive
No full textAlmost half of the world’s human population lives in coastal regions, with 40 % less than ten meters above sea level. Due to population and economic growth in many coastal areas, any negative physical impact on these ecosystems has socio-economic consequences. Globally, Vietnam is among the countries most exposed to coastal hazards. The densely populated 3,260-km long coastline shows a high diversity of coastal landscapes. Satellite archives, such as Landsat, provide a free and powerful opportunity for long-term area-wide monitoring of the coastal zone. An automatic analysis of coastline dynamics from 1984 to 2021 was conducted in this thesis for Vietnam’s entire coastal region. The analysis is based on Landsat-derived annual 75th percentile Modified Normalized Difference Water Index (MNDWI) composites, representing the mean high-water level. Sub-pixel contours are extracted for quantifying coastline change rates along shore-normal transects using linear regressions. A hotspot analysis identifies the coastal segments with the most severe erosion and accretion. The automatic Landsat-based coastline detection yielded a sub-pixel accuracy of 8 m, validated on a single Landsat acquisition. Almost half of Vietnam’s coastline did not experience any significant change, while one quarter has been classified as erosional and one as accretional, respectively. Highest accretion rates with change rates of up to +47 m/year are mainly associated with the construction of artificial coastlines, while highest erosion rates of -28 m/year may be related to both natural sediment redistribution processes and human activity. Most erosion and accretion hotspots are concentrated in the large river deltas of the Mekong in the south and the Red River in the north. Both regions are characterized by rapid economic and population growth. The presented coastline detection approach has additionally been tested in northern Alaska and Sylt (Wadden sea), showing promising results for a potential global transferability of the method
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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