1,720,958 research outputs found
Ricostruzione della distribuzione degli inquinanti gassosi all'interno del "plume" di una ciminiera con metodi remote sensing
Full text linkObiettivo della tesi è presentare lo sviluppo di una metodologia per l’analisi della distribuzione degli inquinanti all’interno del pennacchio uscente da una ciminiera. Lo studio - dopo una presentazione generale dell’atmosfera, della sua composizione e dalla sua interazione con gli effluenti di una ciminiera - propone l’utilizzo di metodi a remote sensing, ovvero misure che da remoto possono fornire informazioni circa la composizione di un pennacchio. In questo contesto la metodologia DOAS (Differential Optical Absorption Spectroscopy), descritta nel secondo capitolo, risulta essere molto adatta per il tipo di indagine proposto. Il terzo capitolo descrive la metodologia di ricostruzione degli inquinanti all’interno del pennacchio e per il calcolo dei flussi di emissione. In questo capitolo sarà inoltre presentato l’apparato sperimentale utilizzato per lo svolgimento delle misure. Infine vengono presentati i risultati di questa metodologia applicata alle navi da crociera, alla ciminiera di un inceneritore, alla ciminiera di una centrale termoelettrica e infine su vaste aree, come ad esempio sul porto. Nelle conclusioni si elencheranno i vantaggi e gli svantaggi dell’applicazione di tale metodologia. Questo studio nasce a Venezia, per rilevare il contributo delle emissioni gassose delle grandi navi da crociera sull’inquinamento totale della zona.The aim of this thesis is to present the development of a methodology for the analysis of the pollutants distribution within the plume of a chimney. The study, after a general presentation of the atmosphere, its composition and its interaction with the effluent from a stack, proposes the use of remote sensing methods, which measures and remotely can provide information about the composition of a plume. In this context the DOAS (Differential Optical Absorption Spectroscopy) methodology, described in the second chapter, turns out to be very suitable for the type of investigation proposed. The third chapter describes the methodology of reconstruction of the pollutants within the plume and for the calculation of the flows of emission. In this chapter will be also presented the experimental apparatus used for carrying out the measures. Finally we present the results of this method applied to the cruise ships, the chimney of an incinerator, the chimney of a thermal power plant and finally over large areas, such as the harbor. In the conclusions we will list the advantages and disadvantages of the application of this methodology. This study was born in Venice, to detect the contribution of gaseous emissions from large cruise ships total pollution in the area
Influence of in-port ships emissions to gaseous atmospheric pollutants and to particulate matter of different sizes in a Mediterranean harbour in Italy
Full text linkShip emissions are a growing concern, especially in coastal areas, for potential impacts on human health and climate. International mitigation strategies to curb these emission, based on low-sulphur content fuels, have proven useful to improve local air quality. However, the effect on climate forcing is less obvious. Detailed information on the influence of shipping to particles of different sizes is needed to investigate air quality and climate interaction. In this work, the contributions of maritime emissions to atmospheric concentrations of gaseous pollutants (NO, NO2, SO2, and O-3) and of particles (sizes from 0.009 mu m to 30 mu m) were investigated considering manoeuvring (arrival and departure of ships) and hotelling phases (including loading/unloading activities). Results showed that the size distributions of shipping contributions were different for the two phases and could be efficiently described, using measured data, considering four size-ranges. The largest contribution to particles concentration was observed for D-p < 0.25 mu m, however, a secondary maximum was observed at D-p = 0.35 mu m. The minimum contribution was observed at D-p around 0.8-0.9 mu m with a negligible contribution from hotelling for size range 0.4-1 mu m. The comparison of 2012 and 2014 datasets showed no significant changes of gaseous and particulate pollutant emissions and of the contribution to particle mass concentration. However, an increase of the contribution to particle number concentration (PNC) was observed. Results suggested that harbour logistic has a relevant role in determining the total impact of shipping on air quality of the nearby coastal areas. Additionally, future policies should focus on PNC that represents an important fraction of emissions also for low-sulphur fuels. DOAS remote sensing proved a useful tool to directly measure NO2 and SO2 ship emissions giving estimates comparable with those of emission inventory approach
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
Contribution of in-port shipping emissions to gaseous pollutants and particulate matter od different sizes in an Adriatic port-city
No full textkoamabayili/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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