1,720,971 research outputs found
Het gedrag van deeltjes in een drinkwater distributie netwerk: Resultaten van een proefinstallatie
Civil Engineering and Geoscience
Removal of Natural Organic Matter Fractions by Anion Exchange: Impact on drinking water treatment processes and biological stability
This researched focused on improving drinking water quality, specifically the biological stability of the produced drinking water. Natural organic matter (NOM) can be a source of nutrients for bacteria present in the distribution system, which can cause regrowth. Specifically, small organic acids can cause bacterial activity in the distribution system and biofilm formation in pipelines can occur. Microbial regrowth can deteriorate the taste and odour of the drinking water and it can even lead to potential health hazards. The biological stability of the treated water is negatively influenced by the presence of certain NOM fractions and therefore, specific NOM fractions should be removed, which can be done by anion exchange (IEX) resins. However, the removal and conversion of specific NOM fractions is not well understood. Therefore, knowledge about NOM fractions as well as their behaviour in water treatment processes is essential. From this research can be concluded that anion exchange is a good and cost-effective way to remove NOM. Liquid chromatography with organic carbon detection (LC-OCD) has shown to be a useful method for NOM characterisation. IEX removed specifically humic acids, which is also the main fraction reacting with ozone resulting in small organic acids. Thus, extension of the treatment lane with IEX before ozonation improves the biological stability of the produced water.Water ManagementCivil Engineering and Geoscience
NOM in de waterzuivering
Drinkwaterbehandeling bestaat uit verschillende stappen, afhankelijk van de kwaliteit van het ruw water. De aanwezigheid van natuurlijk organisch materiaal (NOM) kan problemen veroorzaken in de behandeling en in de distributie van drinkwater. NOM veroorzaakt een hoge coagulantdosering, hoge ozondosering en korte looptijden van actieve kool (GAC) filters. NOM kan een bron zijn voor nagroei in het distributiesysteem en kan de biologische stabiliteit van het drinkwater verminderen. Wanneer het ruw water hoge NOM concentraties bevat, dan moet dit in de drinkwaterzuivering worden verwijderd.Water ManagementCivil Engineering and Geoscience
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
We 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
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