1,720,957 research outputs found
Evaluation of DEM generation accuracy from UAS imagery
No full textThe growing use of UAS platform for aerial photogrammetry comes with a new family of Computer Vision highly automated
processing software expressly built to manage the peculiar characteristics of these blocks of images. It is of interest to
photogrammetrist and professionals, therefore, to find out whether the image orientation and DSM generation methods implemented
in such software are reliable and the DSMs and orthophotos are accurate. On a more general basis, it is interesting to figure out
whether it is still worth applying the standard rules of aerial photogrammetry to the case of drones, achieving the same inner strength
and the same accuracies as well. With such goals in mind, a test area has been set up at the University Campus in Parma. A large
number of ground points has been measured on natural as well as signalized points, to provide a comprehensive test field, to check
the accuracy performance of different UAS systems. In the test area, points both at ground-level and features on the buildings roofs
were measured, in order to obtain a distributed support also altimetrically. Control points were set on different types of surfaces
(buildings, asphalt, target, fields of grass and bumps); break lines, were also employed. The paper presents the results of a
comparison between two different surveys for DEM (Digital Elevation Model) generation, performed at 70 m and 140 m flying
height, using a Falcon 8 UAS
Landslide monitoring by fixed-base terrestrial stereo-photogrammetry
Full text linkPhotogrammetry has been used since long to periodically control the evolution of landslides; however, true monitoring is reserved to
robotic total stations and ground based InSAR systems, capable of high frequency, high accurate 24h/day response. This paper
presents the first results of a fixed terrestrial stereo photogrammetric system developed to monitor shape changes of the scene. The
system is made of two reflex cameras, each contained in a sealed box with a control computer that periodically acquires an image
and send it to a host computer; once an image pair is received from the two cameras, the DSM of the scene is generated by image
correlation and made available for archiving or analysis. The system has been installed and is being tested on the Mont de la Saxe
landslide, where several monitoring system are active. Some instability of the camera attitude has been noticed and is corrected with
an automated procedure. First comparisons with InSAR data show a good agreement
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
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