1,721,064 research outputs found
Vitalità e caratterizzazione chimico-fisica dei pollini come indicatori di inquinamento atmosferico
Full text linkSimple method for determining Si p-n junction depth using anodization
No full textA simple method for the determination of a Si p+/n junction depth is presented. The method is designed to delineate the specific junction due to its importance in the field of Si solar cells where cost effective and fast characterization techniques are necessary. It consists of the electrochemical transformation of the p+ Si to porous Si. The determination of the porous Si depth with the use of cross-sectional Scanning Electron Microscope (SEM) images provides a direct, fast and easy to implement measurement of the junction depth. In addition, through a simple 4-point probe electrical measurement of the sheet resistance, the average dopant concentration is determined, which allows the creation of an abrupt junction approximation of the p+/n junction. The method is shown to produce accurate results in two types of doping techniques, namely implantation and spin-on-doping and a range of junction depths between 200 nm and 1500 nm, as compared to the well-established secondary ion mass spectrometry (SIMS) technique
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
Characterization of the mistura alloy used for Venetian sesino coins: 16th century
No full textThe information provided by material investigations on ancient coins is interesting in many respects, as concerns the archaeological and historical research. In this study a set of Venetian sesino coins, minted over a period ranging from 1554 until 1605, have been investigated in order to shed light on some aspects of the so‐called mistura (mixture) alloy. The widespread diffusion of these relatively low‐value coins of the Venetian Republic, commonly used in commercial transactions in the second half of 16th century, also outside the territories of the Republic, makes them an important proxy to be used in the reconstruction of the political and historical events of the period. The specific issue of the actual composition of the mistura alloy is herewith addressed for the first time, using a combined approach based on X‐ray fluorescence and X‐ray diffraction nondestructively applied to the analysis of the samples. It turns out that the mistura alloy, traditionally regarded as a Cu‐Ag two phase alloy, over the latest period of circulation of the sesino coins, was actually made of copper only, still containing minor concentrations of lead, to be regarded as an impurity of the alloy and not as an intentional addition
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
- …
