1,721,007 research outputs found
Effect of the representative source area for eddy covariance measurements on energy balance closure for maize fields in the Po Valley
Correlazione tra la dimensione del footprint e le variabili esogene misurate da stazioni eddy covariance in Pianura Padana
This article aims to compare the footprint size, estimated by a hybrid model, with the main exogenous variables measured by eddy covariance station. The empirical equations that have been obtained in this article comes from the analysis of the data measured by Livraga (LO) station, and then validated using the data by Landriano (PV) station. The eddy stations are located in a maize field in Po Valley. Furthermore, we want to define some universal relations between the footprint size and these variables and, if necessary, to use the dimensionless variables. The hybrid model is based on a combination of Lagrangian stochastic models and dimensional analysis. The advantage that this study can bring is to have an estimation about the dimension of the representative area that affects the measure of detectors, starting with the knowledge of simple parameters that can be measured easily. The practical purpose is to give, during the time of the project, the correct position of the eddy covariance station in the field, without using expensive instrumentations such as sonic anemometer and gas analyzer. Although, the results of direct comparisons between the footprint and exogenous variables are not very satisfactory, while the comparison between exogenous variables and stability parameter of the atmosphere is particularly interesting. From this comparison we obtained some empirical relations that can be applied to different sites
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
We 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
Comparison between two theoretical footprint models and experimental measurements of turbulent fluxes : the case study of Landriano (PV)
In this work two theoretical footprint models and experimental intra-field turbulent fluxes of latent, sensible heat and carbon dioxide are compared. Experimental data are obtained using a mobile eddy covariance station moving it from a discontinuity point, represented by the field edge, towards the centre of the field where a fixed eddy covariance station is placed. The experimental field is a bare soil at Landriano (PV) in the Po Valley, Italy. The experimental measurements show that latent and sensible heat fluxes have a hyperbolically trend across the field, while carbon dioxide flux is characterized by a linear trend. The maximum relative error between theoretical footprint models and turbulent scalar flux measurements is about 18%
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