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Air scrubbing techniques for the reduction of gaseous emissions from livestock farms. Actual knowledge in the Netherlands and possibilities for implementation on Spanish farms.
No full textIn The Netherlands, packed-bed biotrickling filters and acid scrubbers for removal of ammonia from exhaust air of animal houses are off-the-shelf techniques for ammonia removal. At the moment a new generation of so-called "multi-pollutant scrubbers" is being developed and tested that also removes odour and particulate matter from the air. Air cleaning systems are unusual in Spanish farms. The study of these techniques and their adaptation to Spanish farms, can be an interesting issue in order to achieve the national gas emission reduction commitments, and also to reduce social nuisances
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
Knelpunten in werking luchtwassers
No full textDe laatste jaren is het aantal luchtwassers voor de behandeling van ventilatielucht uit stallen sterk toegenomen. Waren het er vijf jaar geleden nog circa tweehonderd, inmiddels zijn het er ruim duizend en wordt in heel Nederland ongeveer 10 procent van alle lucht uit varkensstallen behandeld in een wasser. In Duitsland is een vergelijkbare tendens te zie
Air treatment techniques for abatement of emissions from intensive livestock production
No full textKeywords: Air treatment; Scrubber; Bioscrubber; Biofilter; Biotrickling filter; Ammonia; NH3; Odour; Livestock production; Animal husbandry; Pig; Poultry. Intensive livestock production is connected with a number of environmental effects, including emissions of ammonia (NH3), greenhouse gases (CH4 and N2O), odour, and particulate matter (PM10 and PM2.5). Possible strategies for emission reduction from animal houses include feed management, adaptation of housing design, and the application of end-of-pipe air treatment, viz acid scrubbers and bioscrubbers. In order to comply with current and future regulations the implementation of air scrubbers is expected to expand in intensive livestock production areas across Europe. The aim of this thesis is to better understand and improve the performance of air scrubber systems in livestock operations. The objectives are to determine (1) how air scrubbers are performing at livestock farms with regard to ammonia and odour removal; (2) how the cost-efficiency of air scrubbers can be increased by applying a different treatment strategy; (3) if methane can be removed by biological air treatment systems; and (4) to discuss the drawbacks of current air scrubbing practices and make recommendations for improvement. It was found that ammonia removal efficiency by scrubbers is relatively high (on average 96% for acid scrubbers and 70% for bioscrubbers), that odour removal is relatively low (on average 31% for acid scrubbers and 44% for bioscrubbers), and that especially bioscrubbers often show a large variation in odour removal efficiency. Furthermore, it was found that bioscrubbers often experience operational problems. Next a partial air cleaning approach has been presented in which air is bypassed at occasionally occurring high air flow rates. Model calculations show that a reduction of scrubber volume by 50% still enables treatment of 80 - 90% of the ammonia load. This strategy reduces investment and operational costs but hardly affects average ammonia emission levels. Furthermore, it was demonstrated that biological oxidation of methane is possible, although the low water solubility of methane limits the practical application of biofilters or bioscrubbers for methane removal. Finally, it is concluded that scrubbers applied at animal houses can still be improved and optimized. For example the process control and performance of bioscrubbers might be enhanced by measurement of electrical conductivity (EC) as a control parameter for water discharge
Biologisch filter voor verwijdering van methaan uit lucht van stallen en mestopslagen = Methane degradation in a pilot-scale biofilter for treatment of air from animal houses and manure storages
Get PDFAppropriate 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
Verwijdering van methaan uit ventilatielucht van een drijfmestopslag met een pilotscale biofilter
No full textMethaan (CH4) is een zeer sterk broeikasgas (21 maal zo sterk als CO2). De veehouderij is verantwoordelijk voor een betrekkelijk hoge emissie van methaan. Het doel van het onderzoek is het ontwikkelen van een biologische luchtbehandelingsinstallatie om de emissie van methaan uit mestopslagen en stallen te reduceren. Gedurende 2 maanden wordt in een biofilter de verwijdering van methaan uit ventilatielucht van een drijfmestopslag getest. Het biofilter heeft een volume van 162 liter, is gevuld met een compost/perliet mengsel en wordt met actief slib geënt. Aangetoond wordt dat methaan succesvol verwijderd kan worden met biofiltratie
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
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