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Sviluppo e implementazione del piano energetico ambientale della provincia di Cremona: un sistema informativo a supporto di Agenda 21
No full textAerial Images from an UAV system: 3D modeling and tree species classification in a park area
No full textThe use of aerial imagery, acquired by the so-called UAVs (Unmanned Aerial Vehicles), is becoming increasingly popular for both geometric and descriptive purposes.
The employment of such type of images is, for instance, scheduled within the FoGLIE project (Fruition of Goods Landscape in Interactive Environment) that was recently funded by Regione Lombardia to give value at the Cultural Heritage by industrial research and experimental development projects.
The project starts from the need to enhance the natural, artistic and cultural heritage, widespread on the Lombardy's territory, and to produce a better usability of it by employing, along predetermined routes, audiovisual movable systems of 3D reconstruction. At the same time, the project comes also from the need to improve monitoring procedures by making use of new media for integrating the fruition phase with the documentation and preservation one.
FoGLIE, which began in October 2010 and will be completed in the following two years, involves some Lombardy firms and Politecnico di Milano, for scientific and technical support in the photogrammetric surveys: these are indeed necessary to produce augmented reality scenes and bird's eye views, besides the widely used 3D visualization. By keeping in mind these aims, the UAVs systems surely represent an innovative and flexible technology, able to collect a big amount of very high resolution information, regarding forest landscape, critical environmental situations and not accessible or not properly enhanced areas.
The pilot project is assessed on a single area, "Parco Adda Nord", suitable due to the presence of various goods' types inside it. Currently, some tests have already been performed to analyze the UAV images' quality with both photogrammetric and photo-interpretation purposes, to validate the vector-sensor system and to optimize the survey planning for 3D modeling and vegetation classification.
A Microdrone MD4-200 was flown, by keeping an altitude of roughly 50 m, over a 200x100 m2 area, chosen because it's partially built-up but also covered by an agricultural field as well as by different tree species and bushes. Thus, multispectral high resolution images were taken by a Pentax OPTIO A40 (a low cost camera), a Sigma DP1 and a Tetracam ADC Lite: the first one was equipped with a CCD sensor with the classic RGB channels whereas the second one had a Foveon specifically modified to acquire the near infra-red band. Instead the last camera had a CMOS sensor (3.2 Mpixel) sensitive to the NIR, the red and the green components thereby yielding directly the so-called "Color Infra-Red" (CIR) images. In fact the IR spectral radiation, besides the visible one, is essential to define the vegetative cover of the territory through classification processes and also to distinguish among different tree species. Lastly, a big number of pre-signalized Ground Control Points has been surveyed through GPS (Trimble 5700 in RTK survey) to allow subsequent accuracy analysis.
Indeed, Aerial Triangulation (AT) and DSMs productions were carried out with two photogrammetric commercial software, Leica Photogrammetry Suite (LPS) and Photomodeler, to pick out pros and cons of each package in managing non conventional aerial imagery as well as the differences in the modeling approach.
Then, cross-comparisons of the results were performed even within the same software by changing the employed set of GCPs and Check Points: this was helpful for studying how much the choice of them could affect the ATs and the E.O. parameters up to the DSMs and the CPs positions. Further analysis were done on the differences between the E.O. parameters and the corresponding data coming from the on board UAV navigation system.
The results of this test phase will be used as guidelines for the following applications on the whole park and for the monitoring of natural and partially urbanized areas through UAVs
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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