With the Big History Italia BH678 Project I have introduced the Big History approach in the Italian middle schools, proposing an interpretation of the history of the universe as a way of creating a ...complex fusion among the sciences and a symbolic path for personal and spiritual growth. Starting from a deep love for complexity, I have written a novel, Storia interiore dell’Universo (now in print for the Italian market), that brings Big History into a poetic and psychedelic landscape. If you want to know the universe, probably, sometimes your body, your brain, your matter are enough; but if you desire to learn from the universe and you work in education, you should consider the whole Homo sapiens, as I believe our species learns only through feeling. Each Big History threshold is an opportunity to feel the echo of some keywords that contribute to developing our Inner Big History, taking off from apparently outer island-moments scattered across spacetime.
Water impacts may have tragic consequences for the passengers of helicopters. Most of the passive safety devices developed for helicopter crashworthiness is designed for ground impact. The loading ...that characterizes the impact with hard and soft surfaces is different and therefore energy absorption devices developed for ground impact are not effective during a water impact.
Various researches focus on the use of composite materials for aircraft and helicopter fuselage. In this paper, in particular, it is investigated the behavior of a composite panel during the impact with water and the approaches to study the event by means of finite element codes.
In order to collect reliable data for numerical model validation, water impact drop tests were carried out. A sample panel, made with a Carbon Fiber Reinforced Plastic material similar to those used for modern aircraft skin panels, was manufactured. A specific test device was created and used in the tests. Impact decelerations and deformation of the panel were measured.
Numerical models of the tests were created. Meshless approaches were used, in addition to Lagrangian and Eulerian Finite elements, to model the water region. Eventually, a close experimental–numerical correlation was obtained for each model in terms of impact dynamics, decelerations and composite panel deformation. The main features of the event and the differences between the four numerical approaches were discussed. Guidelines for further investigations were also drawn.
•Water impact drop tests at several velocities on instrumented CFRP panels.•Evaluation of Lagrangian and Eulerian finite elements models to reproduce water impact.•Evaluation of meshless finite formulations (SPH and EFG) to reproduce water impact.•Meshless formulations are a good alternative to Lagrangian finite elements approach.
In this paper, we introduce a novel approach for automatic pattern recognition and classification of geophysical data based on digital music technology. We import and apply in the geophysical domain ...the same approaches commonly used for Musical Information Retrieval (MIR). After accurate conversion from geophysical formats (example: SEG-Y) to musical formats (example: Musical Instrument Digital Interface, or briefly MIDI), we extract musical features from the converted data. These can be single-valued attributes, such as pitch and sound intensity, or multi-valued attributes, such as pitch histograms, melodic, harmonic and rhythmic paths. Using a real data set, we show that these musical features can be diagnostic for seismic facies classification in a complex exploration area. They can be complementary with respect to “conventional” seismic attributes. Using a supervised machine learning approach based on the k-Nearest Neighbors algorithm and on Automatic Neural Networks, we classify three gas-bearing channels. The good performance of our classification approach is confirmed by borehole data available in the same area.
The High Luminosity Large Hadron Collider (HL-LHC) is the new flagship project of CERN. First endorsed in 2013 and approved in 2016, HL-LHC is an upgrade of the accelerator aiming to increase by a ...factor of ten the statistics of the LHC collisions at the horizon of 2035-2040. HL-LHC relies on cutting edge technologies: among them, large aperture superconducting magnets will replace the present hardware to allow a smaller beam size in two interaction points (IPs). The project involves the construction of about 150 magnets of six different types: the quadrupole triplet, two main dipoles and three orbit correctors. The triplet, manufactured at CERN and in the USA, will consist of 30 magnets based on Nb3Sn technology, with an operational peak field of 11.4 T. These will be the first quadrupole Nb3Sn magnets installed in a particle accelerator. The other five types of magnets, all relying on Nb-Ti technology, present non-trivial challenges in the design and construction; they will be manufactured as part of in-kind contribution under the responsibility of institutes in Japan, China, Spain, and Italy. The project is now in the phase of transition between qualification through short models and prototypes and the beginning of the series construction. In this paper we review the magnet requirements, the reasons for selecting the design, the technological challenges with respect to previous projects, and we summarize the steps that have been taken to validate the baseline.
Determining the effect of structural perturbations on the eigenvalue spectra of networks is an important problem because the spectra characterize not only their topological structures, but also their ...dynamical behavior, such as synchronization and cascading processes on networks. Here we develop a theory for estimating the change of the largest eigenvalue of the adjacency matrix or the extreme eigenvalues of the graph Laplacian when small but arbitrary set of links are added or removed from the network. We demonstrate the effectiveness of our approximation schemes using both real and artificial networks, showing in particular that we can accurately obtain the spectral ranking of small subgraphs. We also propose a local iterative scheme which computes the relative ranking of a subgraph using only the connectivity information of its neighbors within a few links. Our results may not only contribute to our theoretical understanding of dynamical processes on networks, but also lead to practical applications in ranking subgraphs of real complex networks.
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