1,720,985 research outputs found
Smart vs conventional motorways: environmental impact assessment under realistic traffic conditions
No full textThis research aims at assessing the environmental impacts exerted by a smart motorway compared to those of a traditional motorway. The study has global policy implications: it takes into account the impacts due to the construction and maintenance of the infrastructure and the environmental effects produced by the traffic emissions, taking
into account smart technologies and truck platooning regulation. Through a classical LCA approach, 1 km-long smart
motorway with 2 m-high embankment was assumed as the functional unit for the analysis. A realistic traffic condition has been considered. A comparison between environmental effects produced by the use of virgin material and
by Reclaimed Asphalt Pavement was made by assuming two maintenance plans. Thanks to C-ITS systems the greater
safety featured by smart motorways has a significant effect on the environmental impact, compared to conventional
motorways. The impact produced by safety barriers during the life cycle was also estimated. For smart motorways
the impact categories GWP, POCP, AP and EP are observed to be considerably reduced in the maintenance phase of
zinc-coated steel safety barriers and in those associated to traffic emissions. It must be noted that in smart motorways vehicle emissions are markedly influenced by the percentage of heavy vehicles travelling in Truck Platooning
mode. The results show that concomitant use of lime stabilization and RAP leads to a significant reduction in energy
consumption (up to 35%) and pollutant emissions (up to 34% of CO2) than in case of exclusive use of virgin material.
The accidents reduction produce a 30% decrease of GWP, POCP, AP and EP related to safety barriers maintenance
phase than the corresponding values of traditional motorway. Truck platooning mode generates GWP reduction
close to 4%. The environmental advantages of a smart motorway increase progressively with the increase of
AADT, platooning truck percentage and heavy vehicles percentage
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
Il mercato degli UAS: campi di applicazione
No full textL'utilizzo di Unmanned Aerial Systems (UAS) ha avuto un incremento significativo negli ultimi anni. Il loro
impiego, prima riservato ai soli fini militari, si è sempre più rivolto a campi prettamente civili quali, per
esempio la sorveglianza, il controllo ambientale ed il rilievo aereo. Nel presente lavoro verrà esaminata
dapprima l'evoluzione del campo degli UAS nel mondo, verranno esaminati e descritti i primi sviluppi ed
utilizzi fino ai più recenti in modo da dare un panorama completo delle tecnologie in essere, focalizzando, in
una seconda parte, l'attenzione su costruttori e sviluppatori sia europei che extraeuropei. Saranno inoltre
approfonditi gli usi civili degli UAS che, negli ultimi anni, sono divenuti sempre più frequenti. Infine
verranno descritte le principali applicazioni nelle quali gli UAS potrebbero essere utilizzati in Sicilia
A WEB-GIS for the choice of the path in the regional greenways
No full textTourists seem less interested in the traditional sites of mass tourism, which has damaged local identities. The tourist reclaims the old function of journey, intent on widening his knowledge of the surrounding territory, while respecting the social and cultural equality of other population. This study outlines a methodology to identify the generalized cost for a system of no-motorized transport in order to determine the modal choice of users and the route of minimum cost to reach the desired destination. Within the information users, a key role is played by telematics now widely accessible through web interfaces. With the word greenways we mean the network for the no-motorized constituted by paths inserted in a natural context with particular attention to the historic and cultural patrimony of the territory. The trend of research in the field of greenways today is strongly geared towards the infrastructural design of routes. The specific studies and manuals, such as the Dutch CROW, reported mainly geometric patterns of infrastructure, design criteria for parking areas, to improve the transit of pedestrians and bicycles. From the user's perspective becomes relevant fruition with its main attributes: physical effort and safety, especially for no systematic users who may have knowledge about places but not on the tracks and their level of difficulty. In this sense, the greenways are designed both as continuous long-distance routes and as local networks suitable for systematic trips. The GIS contains layers and topological mapping with tourist and local information and network of greenways, composed by individual links with a weight corresponding to the generalized cost needed to pass, which coincides with the physical demands of the user. This effort coincides with the energy to spend to overcome all the resistance to motion characteristics of the link. The study compares the energy expressions derived from physics and kinematics with expressions of experimental nature, to obtain an expression of power required to pass through the link, indicating the degree of difficulty of the route. The user, through the ability to overlay topology, the ease of updating data provided by the GIS and the usability of the information from the web, can plan its journey across the network in response to the level of difficulty related to their physical conditions, the presence of services necessary for the trip and the natural, historical and cultural interest. Information regarding the presence of other transport (bus, rail and private transport) networks for access / egress of the network of greenways and the corresponding service (times, frequency, interchange points) are provide. The design of the network of greenways may contain, in addition to links for the exclusive use roads characterized by low emission and low speed in order to increase the capillary network The study is proposed as a further advancement, the determination of an estimation model from the user in the rate of generalized cost on the perception of traffic safety related to the situation of promiscuity with motorized traffic
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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