1,720,957 research outputs found
Evaluating Wood Fines as a Physical Conditioner for Dewatering Biosludge
Get PDFWood fines are sometimes used to improve biosludge dewatering and to supplement primary sludge, but how they improve biosludge dewaterability is not well understood. Wood fines (0-78% moisture content, dosages of 50-300%), and primary sludge fibres are added to biosludge, dewatered with a Crown Press, and evaluated with a mass balance. The wood fines used absorb on average 2.8ml of water per gram dry weight, which is more water than they help release. Thus, the increase in the dry solid content of the filter cake is primarily due the dry mass of the wood fines themselves, not an increase in water removal. Primary sludge fibres outperformed wood fines when evaluated on the Crown Press without a polymer, but the two conditioners performed similarly when a polymer was used. In a field study, wood fines are found to be an unsuitable physical conditioner when tested in a laboratory scale screw press.M.A.S
Droplet Impact, Infiltration, and Boiling in Pores and Porous Media
Get PDFIn the baking industry, metallic, porous media beds are cyclically heated and then sprayed with water to generate the steam that is crucial for many baked products. Unfortunately, any improvements to these steam generators are slowly made by trial and error because fundamental studies into this mode of steam generation are absent from the literature. Experiments are performed on how individual drops impact and infiltrate long, narrow gaps and porous media to understand the trade-off between impact velocity and pore size on the drop’s infiltration time. Long, narrow gaps are heated to 130°C and 230°C to observe how the gap temperature influences the infiltration and evaporation of a water drop. An evaporation balance is designed to quantify the amount of steam that is generated from a porous media bed and different media bed configurations are tested. The infiltration of water inside narrow gaps and porous media slices can be predicted by a radial capillary model, which is an improvement over the commonly used Washburn capillary rise model. Photographs of the drop simultaneously spreading and infiltrating clearly show that drops commence infiltration into gaps and porous media immediately upon impact for We>7. Cleaving of the drops, when only a portion of the drop infiltrates, occurs when pore sizes are large and/or impact velocities are high. Criteria that predict the cleaving of drops on narrow gaps and porous media are established. For heated gaps, larger gap sizes permitted more of the drop to infiltrate and remain in the gap. For the 100 µm gap size the steam generated inside the gap repeatedly stopped the infiltration. Using the evaporation balance, media beds made from larger media evaporate more water than media beds made from smaller media. The porosity of the media bed did not produce a measurable difference in quantity of steam generated. It is shown that steam generation increases with a decreasing Fourier number and that steam generators should be designed with a FoPh.D
Evaluating Wood Fines as a Physical Conditioner for Dewatering Biosludge
No full textWood fines are sometimes used to improve biosludge dewatering and to supplement primary sludge, but how they improve biosludge dewaterability is not well understood. Wood fines (0-78% moisture content, dosages of 50-300%), and primary sludge fibres are added to biosludge, dewatered with a Crown Press, and evaluated with a mass balance. The wood fines used absorb on average 2.8ml of water per gram dry weight, which is more water than they help release. Thus, the increase in the dry solid content of the filter cake is primarily due the dry mass of the wood fines themselves, not an increase in water removal. Primary sludge fibres outperformed wood fines when evaluated on the Crown Press without a polymer, but the two conditioners performed similarly when a polymer was used. In a field study, wood fines are found to be an unsuitable physical conditioner when tested in a laboratory scale screw press.M.A.S
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
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