1,720,962 research outputs found
Investigating geothermally-sourced H2S pollution in the Reykjavík area: a case study of early March 2017.
No full textAs geothermal energy becomes more widely implemented globally, it is critical to have an accurate assessment of the costs and benefits this technology may pose in order to plan, prevent, and mitigate pollution. Meteorological data sets from the Icelandic Met Office were analyzed in conjunction with hydrogen sulfide (H2S) levels in the Reykjavík area as a case study in the meteorological conditions leading to elevated H2S levels (\u3e50 μg m-3) on March 1-3, 2017. Primary variables of interest were wind speed and direction, temperature, atmospheric stability, and humidity. Climate change is predicted to weaken the Gulf Stream, influencing all of the aforementioned meteorological factors and potentially affecting the frequency of these high concentration events in Iceland. It was found that peaks are most likely to occur in periods with cold (mean: -0.1 °C, median: - 1.2 °C), low velocity (mean: 2.7m/s), easterly winds (mean: 95°), while humidity did not play a significant role. The results of this initial analysis informed the subsequent investigation of the meteorological time series of H2S levels from 2008-April 2017, which supported the previous findings regarding meteorological conditions. The primary goal was to identify similar peak events and search for changes in the frequency of H2S peaks over the past decade. It appears that the introduction of H2S sequestering technology has had a positive effect on reducing the frequency of high H2S events in the Reykjavík area, even when controlling for meteorological effects
Radiocarbon Content of Dissolved Carbon Dioxide and Methane in Cambridge Bay, Canada (2022)
No full text
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
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
Tracking carbon fluxes across ocean interfaces using dissolved gas observations
No full textThe cycling and exchange of carbon between Earth’s systems play a pivotal role in regulating climate, yet two major carbon fluxes remain poorly constrained: the biological carbon pump (BCP) and carbon release from Arctic permafrost. This thesis focuses on dissolved gases as tracers and drivers of these processes through both autonomous and field-based observations. It encompasses (i) improvements to sensor-based measurements of O₂, (ii) the use of these measurements to assess the strength of the BCP in two distinct export regimes, and (iii) isotopic approaches to carbon dioxide (CO₂) and methane (CH₄) dynamics at a coastal permafrost site. The first part of the thesis is centered around the NASA EXPORTS campaign and studies the BCP at two contrasting field sites. Using autonomous platforms, carbon export was evaluated at both sites and demonstrated that at the lower productivity site, a greater proportion of fixed carbon was routed to sinking particulate organic carbon (POC), while the higher productivity site resulted in near equal proportions of dissolved organic carbon production and sinking POC. These findings underscore the value of autonomous sensors in capturing spatial and temporal variability in oceanic carbon cycling. The second part of this thesis shifts focus to the Arctic, where rapid warming threatens to mobilize vast (~1,500 Pg) amounts of carbon currently stored in permafrost. This study presents observations from the spring thaw at a coastal Arctic site and demonstrated that even sites with high CH₄ and CO₂ concentrations drew less than 10% of their carbon source from ancient permafrost sources. The variability in CH₄ and CO₂ emissions reflects the complex interplay between hydrological changes, primary productivity, and microbial processes. The research highlights the need for regular monitoring of Arctic rivers, which integrate changes in the terrestrial system, as a potential early warning system for abrupt permafrost thaw. This thesis leverages the fundamentals of dissolved gas geochemistry to examine key climate-relevant biogeochemical cycles across diverse environments that are sensitive to global change. These insights contribute to refining Earth system models and emphasize the need for expanded monitoring to predict future shifts in global carbon cycling and climate dynamics.Ph.D
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
- …
