Experimental investigation on the bending behaviour of hybrid and steel thin walled box beams—The role of adhesive joints

In the automotive design, nowadays there are two fundamental drivers. On one hand there are the environmental problems, on the other hand there are the safety matters. Within this contest, the weight reduction has become a key driver in the design of vehicles and it is necessary to consider and to study the use of nonconventional materials taking advantage from their high potential of weight reduction and energy absorption capability. In this perspective, the aim of this work is the study of the structural behaviour of box beams by means of a series of three points bending tests. The examined cross sections are those typically used in automotive construction. Different type of materials (steel, composite) and joining technologies (adhesive, spot weld) have been examined, considering different configurations. The work put in evidence the advantages coming from the use of adhesive, which allows structures with important weight reduction and better mechanical properties than traditional joining solution

Numerical simulations of tungsten targets hit by LHC proton beam

The unprecedented energy intensities of modern hadron accelerators yield special problems with the materials that are placed close to or into the high intensity beams. The energy stored in a single beam of LHC particle accelerator is equivalent to about 80 kg of TNT explosive, stored in a transverse beam area with a typical value of 0.2 mm×0.2 mm. The materials placed close to the beam are used at, or even beyond, their damage limits. However, it is very difficult to predict structural efficiency and robustness accurately: beam-induced damage for high energy and high intensity occurs in a regime where practical experience does not exist. The interaction between high energy particle beams and metals induces a sudden non uniform temperature increase. This provokes a dynamic response of the structure entailing thermal stress waves and thermally induced vibrations or even the failure of the component. This study is performed in order to estimate the damage on a tungsten component due to the impact with a proton beam generated by LHC. The solved problems represent some accidental cases consequent to an abnormal release of the beam: the energy delivered on the components is calculated using the FLUKA code and then used as input in the numerical simulations, that are carried out via the FEM code LS-DYNA

Analysis of strain rate behavior of an Al 6061 T6 alloy

Abstract In order to simulate complex scenario like ballistic impact, correct material calibration is fundamental. The material in the area involved by impact can experience high deformation and damage in a very limited time. As a consequence dynamic tests on the materials are needed in order to calibrate constitutive law able to describe the material behavior in terms of hardening and in particular strain rate. According to the fact that no guidelines are available on testing methods, different types of testing techniques have been used to generate data under dynamic conditions. Several dynamic tests, are carried out on Al 6061 T6 specimens and the experimental data elaborated. The developed procedure is useful to take into account also the thermal phenomena generally affecting high strain-rate tests due to the adiabatic overheating related to the conversion of plastic work. The method presented requires strong effort both from experimental and numerical point of view; anyway it allows to precisely identifying the parameters of a material models. This could provide great advantages when high reliability of the material behavior is necessary

The OpenCitations Data Model

A variety of schemas and ontologies are currently used for the machine-readable description of bibliographic entities and citations. This diversity, and the reuse of the same ontology terms with different nuances, generates inconsistencies in data. Adoption of a single data model would facilitate data integration tasks regardless of the data supplier or context application. In this paper we present the OpenCitations Data Model (OCDM), a generic data model for describing bibliographic entities and citations, developed using Semantic Web technologies. We also evaluate the effective reusability of OCDM according to ontology evaluation practices, mention existing users of OCDM, and discuss the use and impact of OCDM in the wider open science community.Comment: ISWC 2020 Conference proceeding

TechMiner: Extracting Technologies from Academic Publications

In recent years we have seen the emergence of a variety of scholarly datasets. Typically these capture ‘standard’ scholarly entities and their connections, such as authors, affiliations, venues, publications, citations, and others. However, as the repositories grow and the technology improves, researchers are adding new entities to these repositories to develop a richer model of the scholarly domain. In this paper, we introduce TechMiner, a new approach, which combines NLP, machine learning and semantic technologies, for mining technologies from research publications and generating an OWL ontology describing their relationships with other research entities. The resulting knowledge base can support a number of tasks, such as: richer semantic search, which can exploit the technology dimension to support better retrieval of publications; richer expert search; monitoring the emergence and impact of new technologies, both within and across scientific fields; studying the scholarly dynamics associated with the emergence of new technologies; and others. TechMiner was evaluated on a manually annotated gold standard and the results indicate that it significantly outperforms alternative NLP approaches and that its semantic features improve performance significantly with respect to both recall and precision

Media use during adolescence: the recommendations of the Italian Pediatric Society.

BACKGROUND: The use of media device, such as smartphone and tablet, is currently increasing, especially among the youngest. Adolescents spend more and more time with their smartphones consulting social media, mainly Facebook, Instagram and Twitter because. Adolescents often feel the necessity to use a media device as a means to construct a social identity and express themselves. For some children, smartphone ownership starts even sooner as young as 7 yrs, according to internet safety experts. MATERIAL AND METHODS: We analyzed the evidence on media use and its consequences in adolescence. RESULTS: In literature, smartphones and tablets use may negatively influences the psychophysical development of the adolescent, such as learning, sleep and sigh. Moreover, obesity, distraction, addiction, cyberbullism and Hikikomori phenomena are described in adolescents who use media device too frequently. The Italian Pediatric Society provide action-oriented recommendations for families and clinicians to avoid negative outcomes. CONCLUSIONS: Both parents and clinicians should be aware of the widespread phenomenon of media device use among adolescents and try to avoid psychophysical consequences on the youngest

Congenital factor XI and factor VII deficiencies assure an apparent opposite protection against arterial or venous thrombosis: An intriguing observation.

To investigate the prevalence and type of thrombotic events reported in patients with congenital factor XI (FXI) or factor VII (FVII) deficiency.Data on all patients with congenital FXI or FVII deficiency and a thrombotic event were gathered by means of a time unlimited PubMed search carried out in June 2014 and in February 2015. Appropriate keywords including the medical subject headings were used in both instances. Side tables were also consulted and cross-checking of the references was carried out to avoid omissions. The thrombosis event had to be proven by objective methods.Forty-three patients with FXI deficiency had arterial thrombosis and only eight had venous thrombosis. On the contrary, only five patients with FVII deficiency had arterial thrombosis whereas 31 patients had venous thrombosis. The arterial/venous ratios were 5.37 and 0.17 for FXI or FVII, respectively.Arterial thrombosis is frequent in FXI deficiency whereas venous thrombosis is rare. The reverse is true for FVII deficiency. The significance of these findings is discussed especially in view of the recent use of synthetic anti-FXI compounds in the prophylaxis of post-orthopedic surgery of venous thrombosis complications