1,720,953 research outputs found
Visiual modflow programı kullanılarak karstik akiferlerindeki yeraltısuyu kaynaklarının yönetimi: Altınova/Türkiye örnek uygulaması
No full textBu çalışma, Antalya'nın karstik özellikteki Altınova bölgesi için gerçekleştirilmiştir. Çalışmanın amacı, Visual MODFLOW Flex kullanarak Altınova'nın karst bölgesindeki yeraltısuyu (YAS) hareketinin simüle edilmesidir. Ek olarak, Altınova'daki YASın mevcut durumunun analiz edilmesi ve geleceğe yönelik yönetim senaryoları kapsamında bölgedeki YAS seviyesinin incelenmesi hedeflenmiştir. YAS seviye değişimi model tahminleri ile elde edilmiştir. Model uygulamasında, mekânsal çözünürlük 25600 m2'lik boyutta ve yaklaşık 75 km2'lik bir alan üzerinde tasarlanmıştır. Model uygulama alanı, jeolojik formasyona göre iki farklı beslenme ve hidrolik iletkenlik bölgesine bölünmüştür. Model, iki boyutlu, kararlı akım koşullarında çalıştırılmıştır. Yanal yöndeki hidrolik iletkenlik, tek kalibrasyon parametresi olarak ele alınmıştır. Modelden elde edilen YAS seviyesi tahminleri, Kasım 2015, Şubat 2016 ve Mayıs 2016'da sahada ölçülen YAS seviyeleri ile karşılaştırılarak model kalibrasyonu gerçekleştirilmiştir. Kurşunlu formasyonunda yer alan ve karstik olmayan alandaki kalibrasyon çalışması sonuçları, traverten karstik alanı için elde edilen sonuçlara göre daha düşük model hatası vermiştir. Genel olarak ölçülen ve tahmin edilen YAS seviyeleri arasındaki korelasyon katsayısı 0,99 olarak hesaplanmıştır. Hem karst hem de karst olmayan alanlar için hidrolik iletkenliğin kalibre edilmiş değerleri 0,01 ila 266 m/gün arasında değişmiştir. Simülasyon dönemi için oluşturulan su bütçesi, akifere giren su akışı ve akiferden çıkan su akışı arasında iyi bir denge olduğunu göstermektedir. Net beslenme, su bütçesindeki en yüksek akış değerini oluşturur ve model sonuçları üzerinde çok etkilidir. Model kalibrasyonu çalışması sonrasında, üç senaryo koşulu oluşturulmuştur. Üç farklı hidrolojik senaryo koşulu için YAS seviyesinde düşüşler görülmüştür. Model tahminleri kullanılarak, YAS akım yönü haritası oluşturulmuştur. Genel olarak, çalışma alanındaki karstik travertendeki YAS kuzeyden güneybatıya ve devamında güneye doğru hareket etmekte iken, karst olmayan akiflerde YAS hareketinin güneye doğru olduğu belirlenmiştir
Hydrogeochemical characterization and assessment of groundwater quality in the Kwahu-Bombouaka Group of the Voltaian Supergroup, Ghana
Get PDFThe Kwahu-Bombouaka Group of the Voltaian Basin, which defines the northern fringe of the basin, constitutes a significant part of the North East Region of Ghana. Most of the inhabitants in the region depend on groundwater for domestic and irrigation purposes. Therefore, a geochemical characterization and assessment of groundwater quality in the area was carried out using hydrochemical, GIS-based ordinary kriging interpolation and multivariate statistical methods on fifty-five (55) borehole water samples. The aim of this study was to determine the concentrations and spatial distribution of various ions, groundwater quality issues and the geochemical processes contributing to groundwater chemistry. The area is largely underlain by sandy shales and mudstones of the Poubogou Formation and feldspathic, quartzitic sandstones with conglomeratic lenses of the Panabako Formation. The abundance of major cations in the groundwater is in the order: Na+ > Ca2+ > K+ > Mg2+ whereas that of the major anions vary in the order: HCO3- > SO42- > Cl-. Na-HCO3 water type is common in the area, which may be due to dissolution from silicate minerals (albite and microcline) in the basement rocks. The results indicate that fluoride (0.01-8.40 mg/L, mean of 0.58 mg/L) and boron (0.01-4.81 mg/L, mean of 0.28 mg/L) contamination is a threat to groundwater quality with respect to their guideline values provided by the World Health Organization. The groundwater chemistry is primarily controlled by ion exchange reactions, weathering of silicate minerals residing in the Panabako Formation and anthropogenic activities from agriculture. Groundwater in the area is largely suitable for drinking purposes although some few boreholes in the northwestern and southeastern parts have high fluoride and boron concentrations. The sodium percentage (11-99%, mean of 70%), magnesium ratios (2.05-57, mean of 29) and sodium adsorption ratio (0.15-38, mean of 4.72) are quite high in some of the communities in the southeastern part of the area. This suggests that water in this part of the area is not entirely suitable for irrigationScientific and Technological Research Council of Turkey (TUBITAK); Earth Science Department of the Faculty of Earth and Environmental Sciences, University for Development Studies; Government of Ghana; European Association of Geochemistry; GeoHost Support ProgramThe first author acknowledges the continuous support from the Scientific and Technological Research Council of Turkey (TUBITAK) as a PhD research fellow of BIDEB 2215 Graduate Scholarship Program for International Students during the time of this research. The second and third authors acknowledge the support of Earth Science Department of the Faculty of Earth and Environmental Sciences, University for Development Studies and the Government of Ghana during this work. This study was also financially supported by the European Association of Geochemistry and the GeoHost Support Program for oral presentation by the first author at the 36th International Geological Congress in New Delhi, India. The Editor Prof. Mohamed G. Abdelsalam, anonymous reviewers, and Prof. Sandow Mark Yidana are greatly acknowledged for the useful reviews
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
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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