1,720,974 research outputs found
Airborne and Ground Induced Polarization integration: new insights for exploration
No full textIt is known and recognized that Induced Polarization effects can affect the Airborne Electromagnetic measurements. These effects, if not treated properly, can represent a source of artifacts, bad fitting, and false recovered structures during the inversion process. At the same time, recognize and properly model the polarization effects can provide a mapping of the spectral content of the recorded data, adding extra information to the results, and allows to properly model the EM. With this work, we modelled the spectral content of Airborne EM data and compared the results with ground IP measurements acquired in the same area. For the modelling procedure, we propose to use the same approach, in order to be more consistent in the modelling procedure. The data we used are from the Iberian Pyrite Belt, one of the most important mining districts in Europe and with the highest concentration of VMS worldwide. Given the geological complexity of the area and the different signatures of the mineralisation style, with our data integration we aim to evaluate the potentialities of the AIP modelling and its role for exploration
Airborne and Ground IP integration for mineral exploration: a Spanish case study
No full textIt is demonstrated and nowadays accepted that the Induced Polarization effects can affect inductive measurements and can be a source of artifacts if not proper modelled during inversion process. At the same time, using a dispersive resistivity to model EM data largely expands the model space and expose the inversion procedure to strong equivalencies and ambiguities. These limitations have often brought to over-precautionary modelling approaches of AIP and leaded to the impossibility in interpretation of the airborne-retrieved chargeability models.
With this contribution a novel modelling approach to extract inductive induced polarization from Airborne EM data is proposed. The AEM data are acquired in Spain, for VMS and polymetallic exploration and overlap 17 ground DCIP lines. The modelling approach we propose concerns a re-parametrization of the Cole-Cole model to an equivalent less-correlated parametrization and a split of the spectral parameters during the inversion procedure. To prove the modelling, a comparison with the ground DCIP lines will be shown. This latter one has been modelled with the same parametrization and inversion scheme of the AEM data to provide a robust comparison between the two and reduce ambiguities in the interpretation. Then, to evaluate the AIP sensitivity to ground chargeable bodies, a joint inversion between the two entire datasets will follow and a vertical and lateral resolution-improved chargeability model is retrieved. This shows the AIP information content and contribute in the enhance of data sensitivity during the modelling procedur
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
Appropriate 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
From Airborne to downhole TDEM: a case study from the Iberian Pyrite Belt
No full textLocated between Spain and Portugal, the Iberian Pyrite Belt is one of the most important mineral districts in Europe with an average production of 20 million tonnes of mineral ore per year. Here, the different mineralization styles, the geological challenges and the weak conductance of the remaining mineralization calls to an integrated approach to constraint the geophysical anomalies, so that to drive the exploration. With this contribute we propose a case study for VMS exploration in the Pyritic Belt where some Airborne EM anomalies have been tested around a known mineralization using ground-based EM methods and modelling approach.
The AEM located conductive bodies have been confirmed by some EM moving loop lines to improve the mineralization modelling and go beyond the depth limits of the airborne method. After the plate modelling, the anomalies have been constrained with several downhole EM surveys and the geometry of the known mineralized body has been defined
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
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
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