1,720,968 research outputs found
The environmental impact assessment of Asphalt Rubber: Life Cycle Assessment
No full textMaterial and energy recovery from end of life tires are the two alternatives to accomplish the European legislation, which has progressively banned landfill disposal with EC Directive 1999/31/EC. Therefore, diversified solutions for end of life tires management should be available to provide a concrete way for reuse and to help to solve the problem of the huge amount of old tires to be treated yearly. Among the material recovery alternatives, road construction using crumb rubber modified binders, called Asphalt Rubber, is already world widely used and is considered an excellent solution to recycle old tires.
In order to support a policy disclosure to this recycled material, the evaluation of the environmental impacts connected to the life cycle of the asphalt rubber is essential and Life Cycle Assessment is a holistic tool which allows for the evaluation of the overall impacts of the road life cycle and of its critical spots.
In this paper, the life cycle assessment of a specific case study of a crumb rubber modified asphalt mixture prepared with the wet method, near Florence (Italy) was evaluated.
The results of the study clearly identify the main contributing steps to the environmental impacts in the life cycle of the rubber asphalt road and therefore, together with the technical and economical evaluation of this technology, will be useful for policy makers when setting the reference specifications in public tenders.Material and energy recovery from end of life tires are the two alternatives to accomplish the European legislation, which has progressively banned landfill disposal with EC Directive 1999/31/EC. Therefore, diversified solutions for end of life tires management should be available to provide a concrete way for reuse and to help to solve the problem of the huge amount of old tires to be treated yearly. Among the material recovery alternatives, road construction using crumb rubber modified binders, called Asphalt Rubber, is already world widely used and is considered an excellent solution to recycle old tires.
In order to support a policy disclosure to this recycled material, the evaluation of the environmental impacts connected to the life cycle of the asphalt rubber is essential and Life Cycle Assessment is a holistic tool which allows for the evaluation of the overall impacts of the road life cycle and of its critical spots.
In this paper, the life cycle assessment of a specific case study of a crumb rubber modified asphalt mixture prepared with the wet method, near Florence (Italy) was evaluated.
The results of the study clearly identify the main contributing steps to the environmental impacts in the life cycle of the rubber asphalt road and therefore, together with the technical and economical evaluation of this technology, will be useful for policy makers when setting the reference specifications in public tenders
Surface investigation of segregation effects in poly(e-caprolactone)-poly(ethylene glycol) based multiblock copolymers
No full text
Comparison between hydrogen and electric vehicles by life cycle assessment: A case study in Tuscany, Italy
No full textThe use of hydrogen produced from renewable energy sources is often reported as an attractive strategy to address the issue of urban environmental sustainability in automotive sector, and a potential alternative to fossil fuel-fed vehicles. The project ‘Filiera Idrogeno’ (Hydrogen Chain) has investigated the potential realisation of hydrogen production chains from renewables and its use as automotive fuel in Tuscany Region (Italy). In this context, life cycle assessment was used for evaluating the environmental sustainability of such chains, applied to a fleet of hydrogen vehicles for urban commercial delivery.
From the energy supply side, renewable wind and biomass energy sources were considered for hydrogen production either by electrolysis or direct separation from biomass gasification syngas, according to specific simulations. Benchmarking with hydrogen produced by using Italian electricity mix was carried out. From the transport side, vehicles equipped with either fuel cell or internal combustion engine were evaluated.
A benchmarking analysis with standard electric vehicles supplied with electricity produced from the same renewable energy sources was also carried out.
The results give some indications on the environmental aspects of the different alternatives and on the contribution of the chain phases to the overall impacts
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
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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