1,720,987 research outputs found
Effetti della preparazione dello spazio per perno endocanalare in canali otturati con un cemento vetro-ionomerico per uso endodontico
No full textNon-destructive and effective bridge monitoring through fast-falling weight deflectometer
No full textRecent collapses due to hydrogeological soil instability caused by extreme climate events recall the attention on a large-scale monitoring of the road infrastructures, particularly bridges and viaducts. Several studies focus the attention on both hydraulic and structural issues. In-depth systematic investigations do not suit this purpose because of time and cost investments usually carried out from local authorities. Increasing needs of available fast, low cost and reliable methods to investigate the performance of the road and bridges pushed towards new applications. The use of Fast-Falling Weight Deflectometer, conceived for airport pavements, is here applied as a non-destructive test to evaluate the stiffness of the deck and embankment of a bridge. The-Fast Falling Weight Deflectometer can produce a broadband, constant and replicable dynamic force, providing data in real time. An experimental campaign is here described on a case study of single span bridge
Maintenance interventions period of existing RC motorway viaducts located in moderate/high seismicity zones
Full text linkConsidering the recent collapses which have affected several existing reinforced concrete (RC) motorway bridges, the correct maintenance interventions planning of these strategic infrastructures has acquired increasing importance to maintain a suitable safety level even in case of seismic loads. One of the most important problems which influences the structural performance of existing RC motorway bridges is the presence of corrosion which may affect the bearing-capacity members. In particular, the corrosion of steel reinforcement of the piers due to the carbonation phenomenon is strictly related to the seismic performance of these structures as the viaducts of the Italian motorway networks realized around the 1970s.In this paper, the evaluation of the seismic vulnerability of three existing RC motorway bridges has been developed using non-linear time history analysis. Three corrosion scenarios (slight, moderate and high) have been analysed. The effects of the carbonation, expressed in terms of piers steel rebars area reduction, have been considered as a function of the age of the viaduct. Risk indices calculated as the ratio of the peak ground ac-celeration leading to collapse of the first structural element and the design peak ground acceleration, are useful to optimize the scheduling of the motorway networks maintenance interventions
Criteria to Identify Streets to Be Pedestrianised Near Major Commercial Attractors: The Case Study of the San Benedetto Market in Cagliari (Italy)
No full textThe paper aligns with the debate on Smart and Sustainable Cities, as outlined by the Sustainable Development Goals (SDGs), with a focus on pedestrianisation and accessibility. It introduces a framework aimed at pedestrianising streets near significant attractors to reclaim car-free public spaces for local communities. Beyond social benefits, the study explores the environmental, economic and health advantages. The research incorporates a comprehensive set of criteria for selecting streets, focusing on functions and streets that are seamlessly compatible to ensure a smooth transition. Criteria, both qualitative and quantitative, were determined after a thorough literature review. These include mobility, land use, accessibility, pavement amenities, street connectivity, safety and security and streetscape design. The research seeks to confirm the potential pedestrianisation of streets close to San Benedetto Market in Cagliari, in accordance with the city administration's objectives. The proposed criteria optimise traffic flow while fostering vibrant pedestrian spaces and enhancing urban accessibility. Preliminary findings demonstrate the beneficial impact of the methodology, including inclusive areas, and enhanced accessibility. The research aims to confirm the feasibility and usability of pedestrianisation, determining whether a measurable method is more effective than a case-by-case approach. The expected results will contribute to understanding the realisability and employability of pedestrianisation, providing valuable insights for administrations. The criteria could serve as a practical tool, offering a systematic and efficient approach useful for urban planners and policy makers to improve traffic management, foster sustainable urban development and interesting pedestrian environments and contribute to a more inclusive and socially connected urban area
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
The structural damping of composite beams with tapered boundaries
No full textMost metallic and composite structures of conventional construction are lightly damped. It is obviously advantageous, in terms of response to inservice dynamic loading, if damping can be increased with minimal weight addition. This paper describes finite element analyses and complementary experiments carried out on composite, carbon fibre-reinforced plastic, beams with tapered boundaries composed of layers of highly damped composite material. It is shown that modal damping of the structures may be significantly increased by this method. Copyright (C) 1996 Elsevier Science Ltd
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
Sardinia Granite Scraps Application in Road Pavement Layers
Full text linkSardinia is the second-largest island of Italy after Sicily, in this region,
large volumes of granite scraps deriving mainly from the ornamental quarry industry,
lie abandoned in stockpiles. The ornamental query industry, very active in the
region since the late 1900s, has produced large volumes of granite scraps causing
several environmental and landscape issues. Therefore, there is a need to find
potential applications for such materials, previously extracted, for which energy
has already been consumed and CO2 emitted. This research focuses on the possibility
of introducing granite scraps for road construction processes. Achieving
several benefits, ecological by restoring landscape integrity and reducing CO2
emissions, economical by decreasing road construction costs. For this reason,
three types of granite scraps, obtained from the same granitic body using two
types of excavation methods and treatment, were studied. In the first phase of the
research the evaluation of the environmental compatibility of the scraps, based on
Italian regulations, was investigated. Also, chemical, and mineralogical analyses
were performed to establish the correct granite family.Mechanical propertieswere
evaluated to assess the possibility of using them to their fullest extent in booth
unbound and hydraulically bound pavement layers. From the test conducted useful
information were obtained showing how granite scraps, can achieve good physical
and mechanical performances if compared with those of natural aggregates
normally used in road pavement layers. The test conducted demonstrated how
granite scraps can be used with high performances in road pavement structures,
contributing to the reduction of quarrying new materials, and introducing a circle
economy approach with several benefits for the Sardinian Island
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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