Early warning system for the prevention and control of unauthorized accesses to air navigation services infrastructures

Early warning systems are fundamental instruments for the management of critical situations since they are able to signal in advance any anomaly with respect to ordinary situations. The purpose of this paper is to present an early warning system, based on artificial neural networks, for the prevention and control of unauthorized accesses to the air navigation services infrastructure in Italy

Parametric thermal analysis for the optimization of Double Walled Tubes layout in the Water Cooled Lithium Lead inboard blanket of DEMO fusion reactor

Within the roadmap that will lead to the nuclear fusion exploitation for electric energy generation, the construction of a DEMOnstration (DEMO) reactor is, probably, the most important milestone to be reached since it will demonstrate the technological feasibility and economic competitiveness of an industrial-scale nuclear fusion reactor. In order to reach this goal, several European universities and research centres have joined their efforts in the EUROfusion action, funded by HORIZON 2020 UE programme. Within the framework of EUROfusion research activities, ENEA and University of Palermo are involved in the design of the Water-Cooled Lithium Lead Breeding Blanket (WCLL BB), that is one of the two BB concepts under consideration to be adopted in the DEMO reactor. It is mainly characterized by a liquid lithium-lead eutectic alloy acting as breeder (lithium) and neutron multiplier (lead), as well as by subcooled pressurized water as coolant. Two separate circuits, both characterized by a pressure of 15.5 MPa and inlet/outlet temperatures of 295 °C/328 °C, are deputed to cool down the First Wall (FW) and the Breeder Zone (BZ). The former consists in a system of radial-toroidal-radial C-shaped squared channels where countercurrent water flow occurs while the latter relies in the use of bundles of poloidal-radial Double Walled Tubes (DWTs) housed within the breeder. A parametric thermal study has been carried out in order to assess the best DWTs' layout assuring that the structural material maximum temperature does not overcome the allowable limit of 550 °C and that the overall coolant thermal rise fulfils the design target value of 33 °C. The study has been performed following a theoretical-numerical approach based on the Finite Element Method (FEM) and adopting the quoted Abaqus FEM code. Main assumptions and models together with results obtained are herewith reported and critically discussed

Properties related to first countability and countable compactness in hyperspaces: a new approach

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Bornologies, selection principles and function spaces

AbstractWe study some closure-type properties of function spaces endowed with the new topology of strong uniform convergence on a bornology introduced by Beer and Levi in 2009. The study of these function spaces was initiated in [G. Beer, S. Levi, Strong uniform continuity, J. Math. Anal. Appl. 350 (2009) 568–589] and [A. Caserta, G. Di Maio, Lʼ. Holá, Arzelàʼs Theorem and strong uniform convergence on bornologies, J. Math. Anal. Appl. 371 (2010) 384–392]. The properties we study are related to selection principles

Uniformizing (proximal) Δ-topologies

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Investigation of fatigue damage growth and self-heating behaviour of cross-ply laminates using simulation-driven dynamic test

Structural integrity of aerospace assets is paramount for both the safety and economy of aviation industry. The introduction of composites into the design of aero-structures generated several economic benefits but also led to several challenges, including fatigue damage growth and self-heating behaviour. Fatigue of metals is widely managed by calculations of damage accumulation and prediction of residual life. These techniques do not always apply to the fatigue of composites, where the onset and propagation of damage are still under investigation. Furthermore, vibration-induced fatigue is even less understood because of a handful of failure criteria available and, also, because it is biased by the self-heating conditions of the material itself. The authors have underpinned one failure criterion for vibration fatigue and mapped that against self-heating and environmental temperatures. Despite the advances, several research questions were left open because of the complex multiphysics behaviour of fatigue which outreached the experimental capacity. Therefore, this research suggests a Simulation-Driven Dynamic Test (SDDT) framework that deconstructs vibration fatigue experiments into step-wise steady-state analyses. This novel approach will enable (a) investigating the failure mode mixity of the underlying failure criterion, and (b) simulating the surface temperature during the delamination growth under vibration conditions.</p

A Method to Discriminate Between the Candida stellata and Saccharomyces cerevisiae in Mixed Fermentation on WLD and Lysine Agar Media

This paper presents a simple method to distinguish between Candida stellata and Saccharomyces cerevisiaeyeasts during microbiological analyses. The method is based on differential yeast growth on a mediumcontaining cycloheximide and a medium containing lysine as only nitrogen source (lysine agar). Thecycloheximide resistance of 45 yeast strains belonging to Candida stellata, Hanseniaspora uvarum, Hanseniasporaguilliermondii, Metschnikowia pulcherrima, Torulaspora delbrueckii, Zygosaccharomyces bailii, Kluyveromycesthermotolerans and Zygoascus hellenicus, and 14 strains of Saccharomyces cerevisiae and Saccharomycesbayanus on WL nutrient agar, was assayed. Cycloheximide resistance is characteristic of the species H. uvarum,H. guilliermondii and Z. hellenicus, while for the other yeasts it depends on the strain and the concentrationof cycloheximide used. Two mg/L of cycloheximide allows selective counting of a strain of C. stellata (Cs3)compared to one of the sensitive S. cerevisiae strain (NDA21). Similar results can be obtained on lysine agar,but counts are reliable only with the additional spreading of a monolayer of Saccharomyces cells. The differentcycloheximide resistance of C. stellata and S. cerevisiae can be used in the microbiological analysis of mixedcultures to monitor the individual growth of the two yeast species. This method can be applied to the studyof mixed fermentations with other non-Saccharomyces species. The modified use of lysine agar is useful to acertain extent in the distinction of multistarter yeasts from the indigenous yeasts