1,721,239 research outputs found
Assessment of two different non-contact scanning methods to survey shape modification of submersed organisms
No full textIn this paper, two different underwater scanning technologies are described, in order to evaluate the 3D shape and colour reconstruction of submerged objects. In particular, a new laser scanner prototype (RGB-ITR) developed in ENEA Centre of Frascati (Roma) is compared with photogrammetric technique. The colour information is an important aspect considered in this work. The laboratory tests are characterized by different structure complexity of the submerged objects. Results provides the difference between 3D models obtained by a 3D colour laser scanner prototype and a low cost cameras in order to highlight the advantages and disadvantages. Copyright © 2018 by the International Society of Offshore and Polar Engineers (ISOPE
Assessing the poplar photochemical response to high zinc concentrations by image processing and statistical approach
No full textExposure of plants to high-heavy metals concentration inhibits multiple metabolic processes in plants and leads to an oxidative stress commonly referred as heavy metal ion toxicity. Chlorophyll a fluorescence has enhanced understanding of heavy metal ion action on the photosynthetic system. A rapid and non-invasive technique involving imaging of chlorophyll fluorescence is a useful tool for early detection of plant responses to heavy metal ion toxicity. In this work chlorophyll fluorescence emission and photochemical parameters in plants of Populus x euramericana clone I-214 were investigated by the portable Imaging PAM fluorometer at different days after soil treatment with zinc. Custom software for analysis of the photochemical parameters images has been developed in order to gain a better assessing of the plant performance in response of metal stress. The imaging analysis allowed visualizing heterogeneity in plant response to high zinc concentrations. The heterogeneity of images suggests spatial differences in photochemical activity and changes in the antenna down-regulation
Quantum process matrices as images: New tools to design novel denoising methods
No full textInferring a process matrix characterizing a quantum channel from experimental measurements is a key issue of quantum information. Noise affecting the measured counts could bring to matrices different from the expected ones and optimization methods usually employed, i.e. the maximum likelihood estimation (MLE), are characterized by several drawbacks. Lowering the noise could be necessary to increase the experimental resources, e.g. time for each measurement. In this paper, an alternative procedure, based on suitable Neural Networks, has been implemented and optimized to obtain a denoised process matrix and this approach has been tested with a specific quantum channel, i.e. a Control Phase. This promising method relies on the analogy that can be established between the elements of a process matrix and the pixels of an image
Multi-wavelengths 3D laser scanner for investigation and reconstruction of 19th century charcoal inscriptions
No full textDigital reconstruction is nowadays a widespread practise and, at the same time, a useful tool in CH field, starting from the study of works of art up to the delineation of conservation actions. The present work describes the use of the ENEA 3D laser scanner prototype, called RGB-ITR, for a deepen investigation of 19th century charcoal inscriptions on wall drawings, placed in the Saint Sebastian Door of the monumental Aurelian Walls (Rome), with the aim of understanding the historical value. The results of post-processing analysis of the high detailed 3D models with properly-developed algorithms allowed the preliminary reconstruction of the contents, demonstrating the value of the adopted technique for 3D digitalization of the room thanks to its features, such as independence from variable lighting conditions, acquisitions at great distances and no need of area interdiction or scaffolds
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
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