1,720,958 research outputs found
Seasonal dune and beach monitoring using photogrammetry from UAV surveys to apply in the ICZM on the Ravenna coast (Emilia-Romagna, Italy)
No full textCoastal monitoring is fundamental to studying dune and beach behaviour related to natural and anthropogenic factors as well as coastal management programs. Various tools have been used in recent years for such investigations, including LIDAR, satellite images, terrestrial laser scanning, and photogrammetry, allowing for both qualitative and quantitative analyses. These tools are applied based on the spatial and temporal scales of the coastal zone being studied. In this study, seasonal coastal changes are monitored using high-accuracy and high-quality photogrammetry frames acquired using unmanned aerial vehicle (UAV). The UAV surveys were performed over two sessions during summer 2014 (September) and winter 2015 (March). Additional data were also acquired during the strongest winter storms of the 2014–2015 season. The results of these two UAVs surveys are compared to identify the changes that occurred on beaches and dunes due to: i) anthropogenic changes such as tourist facilities and winter storm defence construction; and ii) the winter storms of 2014–2015 from dune erosion, investigating the magnitude of impact across all coastal zones under study. Moreover, this study demonstrates the efficacy and applicability of photogrammetry from UAVs for coastal work, analyses whether it is a useful technique for scientific studies and authorities to use due to its greater cost/benefit, and also whether it contributes to the application of local Integrated Coastal Zone Management
Geomorphological analysis and classification of foredune ridges based on Terrestrial Laser Scanning (TLS) technology
No full textAlong the North Adriatic Sea coast (Italy), vulnerability to climate change is further aggravated by anthropogenic influences, such as strong subsidence rate due to deep groundwater and gas abstraction, tourism and industry impacts. In this context, conservation and restoration of coastal sand dunes become extremely important especially because of their importance in terms of ‘natural’ coastal defense. This paper proposes an innovative geomorphological approach based on Terrestrial Laser Scanning - TLS, which allows us to measure and monitor morphometric dune evolution with high precision and details. Several TLS surveys were performed along the Ravenna coast (Adriatic Sea, Italy) and the resulting Digital Elevation Models (DEMs) were analyzed in order to classify the foredune ridges in three geomorphological sub-zones. The topographic, areal and volumetric variations over time of geomorphological units were calculated by GIS tools in order to identify seasonal trends or particular pattern. Meteo-marine climate conditions were also analyzed and Principal Component Analysis (PCA) was performed to correlate changes in morphology with meteo-marine forcing factors, highlighting the ones that most influence dune evolution and dynamics
Valutazione della vulnerabilità costiera nell'area ravennate: il caso di Marina di Ravenna e foce Bevano
No full textLa tesi tratta di un concetto che negli ultimi anni sta diventando sempre più importante e per questo, deve essere studiato e analizzato: la vulnerabilità costiera. In generale per vulnerabilità si intende il carattere di chi o di ciò che è vulnerabile, ossia la sua predisposizione ad essere colpito, attaccato o danneggiato.
Viene anche definita come l’attitudine di un dato elemento o contesto territoriale a supportare gli effetti di un evento dannoso in funzione dell’intensità dell’evento stesso. Questa nozione, in particolare, verrà applicata all’ambito costiero; pertanto si parlerà di vulnerabilità costiera dell’area ravennate. La vulnerabilità costiera è definita come il grado a cui un sistema costiero è suscettibile agli effetti negativi del cambiamento climatico, inclusi la variabilità climatica e gli eventi estremi. Negli ultimi decenni si è giunti alla conclusione che le manifestazioni meteo-marine di estrema entità hanno avuto la tendenza a svilupparsi con maggiore intensità e frequenza (es.: mareggiate).
Questo è il motivo per cui la trattazione verterà su tale argomento, al fine di presentare, chiarire e rendere più esplicita questa tematica, sempre maggiormente presente nella realtà di tutti i giorni.
Nei due siti di interesse: Marina di Ravenna e foce Bevano, sono stati effettuati due transetti, da cui sono stati estratti i relativi profili topografici, sui quali è stato calcolato il Dune Safety Factor, considerando i diversi valori di sopraelevazione marina totale
RIGED-RA project-Restoration and management of Coastal Dunes in the Northern Adriatic Coast, Ravenna Area-Italy
No full textCoastal dunes play an important role in protecting the coastline. Unfortunately, in the last decades dunes have been removed or damaged by human activities. In the Emilia-Romagna region significant residual dune systems are found only along Ravenna and Ferrara coasts. In this context, the RIGED-RA project "Restoration and management of coastal dunes along the Ravenna coast" (2013-2016) has been launched with the aims to identify dynamics, erosion and vulnerability of Northern Adriatic coast and associated residual dunes, and to define intervention strategies for dune protection and restoration. The methodology is based on a multidisciplinary approach that integrates the expertise of several researchers and investigates all aspects (biotic and abiotic), which drive the dune-beach system. All datasets were integrated to identify test sites for applying dune restoration. The intervention finished in April 2016; evolution and restoration efficiency will be assessed
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
Integrated assessment of geomorphological, vegetation and meteomarine dynamics in a beach-dune system (Ravenna, Italy)
Get PDFLa zona costiera è un ecosistema di transizione dove l’interazione di numerosi fattori determina un equilibrio di tipo dinamico, estremamente sensibile agli impatti delle attività antropiche. La costa romagnola, come tutta quella italiana, soffre oggigiorno di un’importante crisi erosiva aggravata dalla subsidenza e dall’intensificarsi di eventi meteomarini potenzialmente erosivi. In questo contesto, la progressiva scomparsa delle dune costiere ha privato il sistema di un’importante difesa naturale ed elemento di resilienza. L’oggetto di studio sono quindi le dune costiere non come elemento isolato ma nell’ottica complessiva di un sistema dinamico e complesso che coinvolge forzanti meteomarine, spiaggia e vegetazione. L’articolazione dello studio ha riguardato prima di tutto l’analisi dei trend evolutivi delle aree dunose a scala secolare, da un punto di vista quantitativo e qualitativo. Lo studio dei fattori fisici ha permesso la definizione del quadro meteomarino di base e l’analisi di mareggiate e storm surge, secondo frequenze attuali e valori estremi. Inoltre, è stata effettuata la caratterizzazione della componente spiaggia da un punto di vista morfodinamico modale. Lo studio della vegetazione costiera in termini di successione spaziale ha evidenziato situazioni di disturbo/naturalità oltre ad importanti relazioni tra specie e valibili morfo-topografiche. Lo ricerca è proseguita quindi con il vero e proprio studio integrato incentrato sullo sviluppo delle dune embrionali (area naturale di foce Bevano) osservando i patterns di sedimentazione/erosione, la risposta ai singoli eventi erosivi, nonché i tassi di crescita in elevazione ed estensione. Le diverse componenti monitorate sono state analizzate in relazione alla dinamica geomorfologica, intesa come aree di accumulo/stabilità/erosione e monitorata tramite tecniche di fotogrammetria Structure from Motion. In conclusione, l’obiettivo dello studio è stato quello di fornire un contributo alla conoscenza delle dinamiche ambientali del sistema costiero, offrendo oltretutto utili indicazioni per la realizzazione di auspicabili interventi di conservazione di questi importanti habitat.Coastal zone is a transition ecosystem where the interaction of several factors determines a dynamic equilibrium that is extremely sensitive to the impacts of human activities. Now a days the Emilia-Romagna’s coast, like overall Italian coast, suffers from a significant erosive crisis that is worsen by land subsidence and storminess intensification. In this context, the progressive disappearance of costal dune is equivalent to deprive the system from an essential natural defense and resilience element. The object of this study is therefore coastal dunes system not as an isolated element but in the overall perspective of a dynamic and complex system that involves meteo-marine forcing, beach and vegetation. The study starts with a preliminary analysis of evolutionary trends of dune areas, on a century scale, from a quantitative and qualitative point of view. In order to describe physical factors, meteo-marine conditions were defined for the area with particular attentions on potential erosive events such as storm-waves and storm surges, considering current frequency and extreme values. Moreover, natural beaches morphodynamic modal state and closure depth values were assessed. The study of coastal vegetation in terms of spatial sequence showed different situations of disturbance/naturality as well as important relationships between species and morpho-topographical parameters. Research continued then with the actual integrated study focusing on embryo dunes development, in the natural area of Bevano torrent mouth, observing for a year the sedimentation/erosion patterns, the response to single erosive event and growth rates in elevation and extension. The others environmental components monitored were analyzed in connection to geomorphologic dynamic, evaluated in terms of areas of deposition/stability/erosion and surveyed by ground-based and Structure from Motion photogrammetry. In conclusion, the study objective was to provide a contribution to environmental coastal dynamics knowledge, offering moreover useful indications for desirable restoration and conservation actions of this important habitat
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
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