1,720,973 research outputs found
MICRO UAV FOR POST SEISMIC HAZARDS SURVEYING IN OLD CITY CENTER OF L'AQUILA
No full textAlmost three years ago a disastrous earthquake hits the old city of L'Aquila, hundreds of victims, thousands of collapses. The post emergency and very crucial phase regarding surveys, structure controls and investigations till now is fully underway. Conventional surveying techniques using high precision total stations, GNSS and laser scanners for investigations on damaged buildings are always becoming more automated, accurate and operative in always shorter time manners. Even if these techniques represent instruments of extreme operability there are still many evident limits on their use especially regarding the survey of both the roofs and the facades of tall buildings or dangerous places, typical on post earthquake situations. For example, the details of a bell set at 40 m height are always hidden for most of the instruments such as laser scanners or total stations, certainly, the non optimal capturing angle and the bad visual would represent considerable limits for the identification of potential damages. The present work aims on experimenting an innovative surveying methodology using multirotor UAVs (Unmanned Aerial Vehicles), fully remote controlled, that will allow high quality image capturing on roofs and facades of structures in the old city center of L'Aquila. These data will be elaborated with photogrammetric software suits to create digital models of the building and databases with its detailed characteristics. The field of application can be the concept of photogrammetry of proximity as the flights are carried out at altitudes much lower than an aerial photogrammetry, moreover, as the flight is operated in a fully automated way, extended areas can be surveyed in a fat and economic way. This paper highlights the reasons that led to explore the use of a Micro UAV in the relief of an old city center through a real case application. Each step of photogrammetry is described, from the planning software of the flight plan and gripping points to ensure the coverage required to the execution of the flight and the data processing. The experiments were performed using an IPT Mikrokopter (Rome - Italy), in octo-configuration (8 engines) in order to have better flight stability and raise the needed payload for an SLR digital camera; the flight was also performed in fully automatic way at the height of 80m. The results presented in this study highlight the excellent integration of these surveys with those made by conventional instruments and propose this methodology as an effective documentation necessary for a recovery of an old city in a post natural disaster
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
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
UAV Photogrammetry and OBIA Classification for Decay Mapping in Built Heritage
No full textOne of the first steps in the development of BIM (Building Information Model) for existing structure is linked to the acquisition and mapping of decay information. Currently, the most widely used practice is visual inspection carried out by experts in the field an based on visual inspection, that requires significant effort in terms of time, human resource and operational costs. To overcome many of the current challenges, the use of Unmanned Aerial Vehicle (UAV) photogrammetry combined with Object-Based Image Analysis (OBIA) techniques represents an innovative approach for non-invasive methodology for decay mapping. The paper presents the results of the integrated approach applied on two case study, differing in types of decay observed and materials. The first involves a building's façade mainly affected by crusts due to washout, and the second concerns a section of a concrete infrastructure, which is affected by different types of surface degradation (cracks, spalling, exposed bars and stains). The results were validated using different approaches in function of the decays observed: in the first case study a cross validation was performed and in the second one a confusion matrix from a ground truth was extracted. The results show satisfactory performance on the OBIA classification in both case study. The methodology developed overcomes some limitations of traditional methods and, the obtained maps, can be integrated in BIM models to enrich the informative content and subsequently support the development of strategies for improving the energy efficiency of the built environment
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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