1,720,962 research outputs found
Fotogrammetria digitale terrestre per la realizzazione del modello 3D di un ravaneto storico delle Alpi Apuane
No full textGli agri marmiferi di Carrara, nelle Alpi Apuane, rappresentano l’esempio classico di un territorio interessato da un elevato impatto antropico dovuto all’intensiva attività di coltivazione ed estrazione di marmo. La zona, d’altra parte, è caratterizzata dalla presenza di strutture antiche realizzate dall’uomo di particolare interesse culturale, come “tagliate” (tecniche di lavorazione nelle cave di marmo d’epoca romana) o “ravaneti” (coltri detritiche costituite dal materiale di scarto dell’attività estrattiva), che costituiscono un’importante testimonianza storica delle attività di sfruttamento del bacino marmifero dai tempi più antichi.
Considerata la dinamicità dell’evoluzione morfologica dell’area, talvolta tali antiche strutture possono essere soggette a smantellamento nei casi in cui la loro ubicazione interferisca con l’attività di sfruttamento prevista dagli attuali piani di coltivazione. Da ciò è nata la necessità da parte dell’Autorità Comunale di creare un prodotto che abbia la funzione di “memoria storica” della struttura smantellata e che costituisca non solo un supporto visivo (come una semplice fotografia), ma un supporto informativo più completo, dotato di caratteristiche geometriche esaustive ed in grado di garantire una visualizzazione dell’elemento d’interesse nelle tre dimensioni.
Nel presente lavoro viene presa in esame la costruzione di un modello tridimensionale di un ravaneto storico mediante l’utilizzo di tecniche di fotogrammetria digitale terrestre. Vengono esaminate le fasi di acquisizione dei fotogrammi mediante barra fissa calibrata, orientamento e triangolazione, estrazione di modelli digitali di superficie (Digital Surface Model - DSM), produzione di elaborati ortofotografici e modellazione tridimensionale
Close range photogrammetry for the analysis of unstable slopes in the Apuan Alps marble quarries (Carrara, Italy)
No full textDigital terrestrial photogrammetry for the quarry slope stability analysis in the Apuan Alps Marble District
No full textDigital terrestrial photogrammetry by aerostatic balloon for rock slope stability analysis
No full textContributions of digital photogrammetry for the study of rock slope stability by conventional methods with limit equilibrium and numerical methods with distinct elements [Contributi di fotogrammetria digitale per lo studio della stabilità dei versanti in roccia attraverso metodi convenzionali all’equilibrio limite e metodi numerici agli elementi distinti]
No full textThe Aim of the project is the study of the brittle structures in rock slopes for stability evaluation of rocky slopes by deterministic approach. This is done through the application of Photogrammetry
techniques for detailed survey of jointing systems and versant
geometry. The digital terrestrial Photogrammetry is a technique that can be used for a detailed survey especially in hardly accessible sites and from it oriented stereoimages, accurate digital elevation models and orthophotos can be created; then, it can be used as data source for studying the rocky slope stability both by Conventional and Numerical Methods
Applied Digital Photogrammetry to joints and rocky blocks geometrical analysis
No full textAim of this paper is the description of a methodology purposely developed to study brittle
structures in rocky slopes for both site exploitation and stability evaluation in marble quarries by deterministic
approach. This is obtained by the application of digital terrestrial photogrammetric techniques that can be
used for detailed surveys, especially in hardly accessible sites. Oriented stereo images, accurate digital elevation
models and orthophotos are the main deliverables that are expected from photogrammetry; then, such
technique can be used as data source for studying geomechanical characteristics of the slopes. The proposed
method in studying rock fall introduces innovative and meaningful elements related to the deterministic approach,
for the individuation of dangerous portions, and to the three-dimensional analysis of blocks geometrical
relationships with bounding joints
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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