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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
Geochemical and stable isotope studies of groundwater and river water in the Bor and Majdanpek porphyry copper mining areas in Eastern Serbia: Implications for the environmental impact on groundwater
Get PDF秋田大学博士（理学）Contamination of water bodies is a large problem in many mining areas in the world. A similar problem exists in Eastern Serbia, where mining activities have been carried out for about 120 years. Currently, in Eastern Serbia, there are four active copper mines, three in the Bor mining area and one in the Majdanpek mining area. The long history of mining in the Bor mining area has led to serious environmental problems, which are most pronounced on water pollution downstream of the mining sites. This research aims to clarify the geochemistry of river water and groundwater in the study area and to estimate the environmental impact on groundwater in the Bor and Majdanpek mining areas.
River water of Bor River, Krivelj River and Bela River located in the Bor mining area showed acidic pH ranging from 2.9 to 5.1, from upstream to downstream direction, with high concentrations of SO42-, Fe, As, Cu and Mn. River water of Small Pek River and the upper reach of Pek River are characterized by weakly alkaline pH and high concentrations of SO42-, Fe, As, Cu and Mn, although lower than the concentrations of these components in river water in the Bor mining area. The acidic river water in the Bor mining area transports large quantities of heavy metals and arsenic downstream, including 6900 t/year of Fe, 42 t/year of As, 910 t/year of Cu and 187 t/year of Mn. On the other hand, the weakly alkaline river water in the Majdanpek mining area transports smaller quantities of heavy metals and arsenic downstream (160 t/year of Fe, 0.1 t/year of As, 6 t/year of Cu and 272 t/year of Mn). This indicates that the environmental impact in the Bor mining area is significantly larger than that in the Majdanpek mining area. However, concentrations of SO42-, Fe, As, Cu and Mn in Bela River in the Bor mining area have greatly decreased after mixing of acidic polluted water of Bela River with water of Timok River containing a high bicarbonate concentration. This fact suggests that river water in the study area including Bor and Majdanpek mining areas has sufficient capacity for neutralization.
Stable isotope ratios of groundwater are typical for the moderate continental climate. However, groundwater samples collected in mountainous areas are relatively depleted in δD and δ18O compared with samples that are collected in plain areas of the
study area. This difference is thought to be caused by the altitude effect due to the Rayleigh process, which means that precipitations enriched in stable isotopes, that form groundwater in the study area, will occur first in the plain areas, and going towards higher altitudes precipitations will become depleted in stable isotopes.
Groundwater in the study area is characterized by pH values ranging from 6.4 to 8.8 and a high concentration of HCO3-. The groundwater is Ca-Mg-HCO3-dominant type water. In general, groundwater from the study area has good quality with low content of trace elements, which are below maximum admissible concentrations according to the Serbian standard for drinking water. Trace elements that are mainly present in groundwater are Ba and Sr. Barium and strontium concentrations are especially high in limestone-rich areas.
To determine whether mining activities are causing groundwater pollution in the study area, geochemical maps were created and threshold values for discrimination of anomalous populations from background populations were estimated for Ca2+, SO42-, and 24 other components. Geochemical maps created for Ca2+ and SO42- show that groundwater with high concentrations of these components is found along polluted rivers downstream of the Bor mining area, especially in the area along the Bela River. The actual concentrations of Ca2+ and SO42- exceeded the threshold values, although the concentrations in some groundwater samples in the area downstream of the Bor mine were below the standard values. Pollution of the groundwater along the polluted rivers is therefore thought to have been caused by mining activities of the Bor mine. Elevated concentrations of the studied components in groundwater from the Majdanpek mining area were not detected.
Based on the mixing analysis between interstitial water present in tailings along strongly polluted rivers and unpolluted groundwater, it is thought that interstitial water in tailings along Bor River and Bela River is causing pollution of groundwater in the vicinity of those rivers. While river water does not directly affect groundwater in the study area.
Calcium and sulfate concentrations were shown to be good indicators for monitoring of early-stage groundwater pollution caused by mining activities in the
study area, this evaluation is mainly suitable for groundwater with a near-neutral pH. In addition to this, the evaluation method used in this study, which is based on geochemical maps, threshold values and mixing analysis considering geochemical reactions, is widely applicable to environmental assessment in mining areas
Geochemical and stable isotope studies of groundwater and river water in the Bor and Majdanpek porphyry copper mining areas in Eastern Serbia: Implications for the environmental impact on groundwater
No full textAppropriate 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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