1,722,496 research outputs found
Notice nécrologique sur M. Adam
No full textFriedel Charles. Notice nécrologique sur M. Adam. In: Bulletin de la Société minéralogique de France, volume 4, 6, 1881. pp. 143-144
Notice nécrologique sur M. Adam
No full textFriedel Charles. Notice nécrologique sur M. Adam. In: Bulletin de la Société minéralogique de France, volume 4, 6, 1881. pp. 143-144
Cost-effective monitoring of structural risk of bridges supported by cutting-edge technologies
Get PDFBridges and viaducts are crucial components of transportation network, and activities as risk assessment and structural maintenance are crucial to avoid economic losses and casualties due to their collapse. External actions, natural hazards, material degradation and aging affect safety and serviceability of bridges. The effort required by national guidelines, as the one issued in 2020 in Italy, pose questions about the resources required for large-scale screening and risk assessment of large bridge portfolios, mostly populated by simply supported concrete girder bridges, both reinforced and prestressed (PSC). The main challenge is to leverage cutting-edge technologies for a cost-effective near-continuous monitoring of structural risk of bridges.
In the field of remote-sensing technologies, Interferometry via Synthetic Aperture Radar and Unmanned Aerial Vehicle photogrammetry are two emerging technologies that meet requirements to achieve the goal. Large coverage, adequate resolution and accuracy, and acquisition frequency are them strengthen points at the base of two proposed frameworks. The combination with basic structural knowledge of bridges and environmental data represents a promising mix for portfolio structural risk assessment of existing bridges and structures as demonstrated in the explored case studies.
Although these technologies are affected by limitations, their constant use can help to identify bridges requiring a more refined structural risk assessment based on traditional structural health monitoring systems (i.e., sensor-based). Some bridge typologies as PSC box-girder bridges pose additional challenges requiring more effective strategies to monitor prestressing force reduction. Machine learning surrogate models as Artificial Neural Networks coupled with eXplainability approaches are demonstrated to be effective when integrated with traditional sensor-based systems. The experimental campaign on a scaled PSC box bridge is a great example of this combination.
The cost-effective monitoring of structural risk of bridges supported by cutting-edge technologies is a true example of the ongoing change in civil engineering that will flourish in the years to come thanks to the technical and scientific progress
Automation and information approaches to support maintenance and production management in the construction industry
No full textThe construction industry is a wide industrial sector ranging from the design and
management of major infrastructures, such as bridges, to civil dwelling construc-
tion. It is worldwide acknowledged as a fundamental driving sector for the Gross
Domestic Product, but it is also among the less performing and delayed ones in
the adoption and exploitation of technological improvements. These limitations are
inducing stakeholders to borrow and integrate many enhancements from other indus-
trial fields into the sector. This digitalization trend is spreading through the entire
life cycle of the construction process and identifying a challenging approach because
of the paradigm shift needed from physical to cyber-physical systems. The Industry
4.0 concept boosted this trend so that both in the academy and in the construction
industry it has been specified as Construction 4.0. It borrows from the Industry 4.0
the adoption of many key enabling technologies such as Internet of Things, Artificial
Intelligence and Additive Manufacturing. This thesis investigates specifically this
technological integration, focusing on the application of such enabling technologies
in the construction field and considering different stages in the life cycle in vary-
ing infrastructure typologies. Starting from a literature investigation on "holistic"
intelligent systems in Intelligent Buildings construction, in a Digital Twin fashion,
the influence and the application of enabling technologies and related operative ICT
tools such as Internet of Things and Big Data are studied, from a perspective of
the whole constructions’ life cycle. The maintenance phase of major infrastruc-
tures is studied concerning structural safety and fault detection, by developing a
method to detect damages in railway steel truss bridges via artificial intelligence.
An innovative additive manufacturing technology for high-rise constructions is then
presented. It consists of an improvement with a custom extruder of standard tower
crane technology, while the whole system is driven by an artificial intelligence agent.
We conclude that Construction 4.0 is still at its embryonic stage. More advanced
results are obtainable for the operation and maintenance management of existing infrastructures because of the already mature approach related to sensorization and
data analysis. Innovation in the design/construction phase remains more challenging,
because of the need for a completely new paradigm and industrial innovations in
many different fields
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
O MODELO DOS ESQUEMAS SEQÜENCIAIS DE J.-M ADAM: SOLUÇÃO OU PROBLEMA?
No full textO MODELO DOS ESQUEMAS SEQÜENCIAIS DE J.-M ADAM: SOLUÇÃO OU PROBLEMA
Development of a Decision Support System for the structural degradation analysis of RC buildings supported by user-reported data and modern Information Technologies
No full textExposure to aggressive environmental agents and aging can seriously harm reinforced concrete (RC) structures and affect the building’s service life. In particular, many buildings built during the extensive dissemination of RC construction technique present criticalities regarding performance and durability due to many issues: inadequate design of technical details, incorrect execution method, inadequate materials, improper maintenance or intrinsic limits and vulnerability of concrete.
Consequently, management and monitoring of existing buildings is a complex issue for holders and administrators that are responsible for the building operability and user safety. On the other hand, large-scale degradation analysis and maintenance procedures present critical points: i) non-uniform building knowledge, ii) need of performing several inspections, iii) complexity of the diagnostics related to the subjectivity of the surveyor, iv) vastness and deployment of buildings in the region. Such issues become particularly complex for public or private administrators, who usually have limited resources and often cannot rely methodologies and tools to face the problem. This thesis proposes an innovative approach for detecting building criticalities. In order to achieve the new system, four synergistically related methods are suitably developed and listed as follows: i) a novel DSS methodology for buildings’ assessment supported by modern Internet of Things tools (smart devices) and Information Technologies; ii) an innovative Optimized AHP (O-AHP) based on a Mathematical Programming problem; iii) a calibration procedure based on the Tuutti model to consider the damage evolution of reinforcements’ corrosion and tune the KPIs; iv) a Test Site involving 131 building on the Valencian coasts to test the DSS. In particular, the proposed DSS includes an innovative software application (APP) implemented on mobile devices and a web service–based Quality Detection Platform (QDP) that stores and processes data. The APP allows the building users to report criticalities through photographic acquisition and to answer a specific questionnaire. Collected data are processed by the QDP, which quantifies critical issues through the set of key performance indices (KPIs). The DSS allows monitoring buildings at the regional scale and provides a classification of the most damaged buildings, which is useful for civil protection aims and for the prioritization of interventions
- …
