1,720,965 research outputs found
Séparation de phases et digestats : profils d’efficacité basés sur les intrants de digestion anaérobie et le choix du séparateur
No full textAnaerobic digestate˸ characterization and new valorization routes
No full textLes post-traitements des digestats de méthanisation peuvent être inévitables, en particulier pour les exploitants d'installations non agricoles. Les options existantes pour la valorisation des digestats non-agricoles (NAD) sont limitées, souvent coûteuses et créent peu de valeur. L'objectif de cette thèse a été d'améliorer la valorisation des NAD via (i) une meilleure description et compréhension de la variabilité de la qualité des digestats et (ii) l'exploration de nouvelles voies de valorisation.Une typologie de la valeur fertilisante des digestats a été établie. Six types ont été différenciés en lien avec les intrants de méthanisation et le procédé (voie humide ou sèche). Les paramètres qui décrivent le mieux ces types sont la matière sèche du digestat, la teneur en azote et le rapport C/N. Ensuite, une méta-analyse a permis de mieux prédire la séparation de phase des digestats, une étape essentielle des configurations existantes. Ces deux études contribuent à mieux expliciter la variabilité de la qualité des digestats tant pour les scientifiques, les concepteurs et les opérateurs de méthaniseurs.Le «fractionnement» du digestat a été la principale approche expérimentale des voies innovantes explorées. La preuve de concept d'un procédé capable simultanément de stripper de l'azote et d'extraire des substances humique-like a été démontrée. Ces extraits ont été caractérisés et évalués en tant qu'amendements, biostimulants et biosurfactants. Enfin, l'approche de «conservation » a consisté en un séchage thermique direct du digestat brut, mais en privilégiant la fixation de l'azote. À cette fin, un acide et un adsorbant, comme améliorateurs de procédé, ont été appliqués avant le séchage. Seule l'acidification a permis de conserver l'azote et des limites expérimentales ont été discutées.L'exploration de nouvelles voies de valorisation des NAD a été fructueuse: des nouveaux concepts ont été testés et des perspectives positives proposées pour ouvrir des nouveaux marchés à partir de digestats. La valorisation efficace du digestat reste un défi, mais la thèse ouvre de nouvelles possibilités concrètes ainsi que de nouvelles questions scientifiques et techniques à explorer.Anaerobic digestate (AD) post-treatments can be unavoidable, especially for operators of non-agricultural AD facilities. Current options for the valorization of non-agricultural digestates (NAD) are limited, often costly and with low value creation. The objective of this thesis was to enhance NAD valorization routes through (i) better explaining digestate quality variability and (ii) assessing the potential of new recovery options for different types of digestates.A digestate fertilizing-value typology consisting of 6 different types was established. The types were linked to AD feedstock and process (wet or dry-AD). The typology was mainly described by digestate dry matter, nitrogen content and C/N ratio. After, a meta-analytic study allowed a better prediction of digestate phase separation efficiency, which is usually a key step on digestate valorization. These two studies clarify the variability of digestates for scientists, plant designers and operators.Digestate “fractioning” was the principal approach and the experimental focus of innovative digestate recovery. The proof-of-concept of a scalable process capable of stripping nitrogen and extracting humic-like substances was demonstrated. The extracts of humic-like substances were characterized and assessed as soil improvers, biostimulants and biosurfactants. Finally, the digestate “conservation” approach consisted of direct thermal drying of raw digestate but with a focus on keeping nitrogen. For this purpose, acidification and adsorbents, as a novelty process enhancer, were applied before drying. Only acidification was successful for N fixation under the tested conditions and experimental limits were highlighted.The exploration of innovative NAD valorization approaches was successful: new concepts were developed along with positive perspectives for entering new markets from digestates. Effective digestate valorization remains a challenge but the thesis opens new concrete possibilities, along with new scientific and technical questions to be investigate
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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