1,083 research outputs found
Territorial longitudinal strain discloses the culprit vessel in a patient with non-ST-segment elevation acute coronary syndrome
No full textFor the study relating to this case report see A. I. Guaricci, G. Chiarello, E. Gherbesi, L. Fusini, N. Soldato, P. Siena, et al. Coronary-specific quantification of myocardial deformation by strain echocardiography may disclose the culprit vessel in patients with non–ST-segment elevation acute coronary syndrome. European Heart Journal Open 2022; doi: 10.1093/ehjopen/oeac010
The full stereo drift chamber for the MEG II experiment
No full textThe MEG experiment, at the Paul Scherrer Institute (PSI) near Zurich in Switzerland, aims at searching for the charged-lepton-flavor-violating decay μ+ → e+γ, prohibited in the Standard Model but allowed, at a measurable level, in many of its extensions. MEG has already determined the world best upper limit on the branching ratio: BR(μ+ → e+γ) < 4.2 × 10-13 at 90% CL with the full data set collected in the years 2009-2013. A further improvement of the MEG single event sensitivity requires a substantial upgrade of the detector performances and, in particular, the complete replacement of the positron tracker. The MEG upgrade experiment (MEG II) is currently under construction and it is conceived in order to further improve the sensitivity by one order of magnitude in three years of data taking. The new positron tracker is a high transparency single volume, full stereo cylindrical Drift Chamber, immersed in a non uniform longitudinal B-field, co-axial to the muon beam line. Due to the high wire density (12 wires/cm2), the use of the traditional feed-through technique as wire anchoring system could hardly be implemented and therefore it was necessary to develop new wiring strategies. The number of wires and the stringent requirements on the precision of their position and on the uniformity of the wire mechanical tension impose the use of an automatic system to operate the wiring procedures. The drift chamber is currently under construction at INFN Lecce and Pisa, and should be completed by the summer 2017 to be then delivered to PSI for commissioning. The upgraded detector, the new drift chamber and its construction technique, will be described
The cylindrical drift chamber for the meg II
No full textThe MEG experiment, at PSI in Switzerland, aims at searching the charged lepton flavor violating
decay m+ ! e+g. MEG has already determined the world best upper limit on the branching ratio: BR<4.2×10−13
@90\%CL with the full data set collected in the years 2009-2013. The new positron tracker is a high transparency single volume, full stereo cylindrical Drift Chamber (DC), immersed in a non uniform longitudinal B-field, co-axial to the muon beam line with length of 1:93 m, internal radius of 17 cm and external radius of 30 cm. It is composed of 10 concentric
layers, divided in 12 identical sector of 16 drift cells each. The single drift cell is approximately
square, with a 20 mm gold plated W sense wire surrounded by 40 mm silver plated Al field wires in a ratio of 5:1. For equalizing the gain of the innermost and outermost layers, two guard layers have been added at proper radii and at appropriate high voltages. The total number of wires amounts to 12288 for an equivalent radiation length per track turn of about 1.45x10-3 X0 when the chamber is filled with an ultra-low mass gas mixture of helium and iso-butane. Due to the high wire density (12wires=cm2), the use of the classical feed-through technique as wire anchoring system could hardly be implemented and therefore it was necessary to develop new wiring strategies. The number of wires and the stringent requirements on the precision of their position and on the uniformity of the wire mechanical tension impose the use of an automatic system (wiring robot) to operate the wiring procedures. Several tests have been performed in different prototypes of the drift chamber, exposed to cosmic rays, test beams and radioactive sources, to fulfill the requirement on the spatial resolution to be less than 110 mm. The drift chamber is currently under construction at INFN and should be completed by the end of 2017 to be then delivered to PSI
Estimating Industry 4.0 impact on job profiles and skills using text mining
No full textIndustry 4.0 is introducing rapid and epochal changes and challenges. Among these, the issue of skills and job profiles is assuming a critical role. In fact, the literature highlights not only the necessary integration of existing skills in professional profiles, but also the inevitable creation of new ones to properly manage the digitalisation trends. Although, the state of the art mostly focuses on building models to assess the digital maturity of companies, considering instead the impact on the labor market as a hazy issue. Moreover, the literature tends to offer qualitative approaches to the topic, making the results uncertain; on the other side, quantitative ones tend to be mainly applied on structured databases, while the supply and demand of competences (findable in CVs, vacancies or firm's job profiles) are less treated. The goal of the present research is developing a measure for quantifying the readiness of employees belonging to a big firm with respect to the Industry 4.0 paradigm. To reach the goal, a data-driven approach based on text mining techniques is applied to a case study. In particular the present methodology makes use of a previously developed enriched dictionary of technologies and methods 4.0 (Chiarello et al., 2018). The source is used to analyze job profiles’ descriptions belonging to Whirlpool, a multinational company with a structured database of jobs and skills. The process allows the identification of technologies, techniques and related skills contained in job descriptions. Starting from these, the Industry 4.0 impact on each job profile is measured. Finally, the metadata of the job profiles are analyzed to evaluate to which extent the skills of profiles 4.0-ready and non-4.0-ready differ. In the end, the work provides a framework for estimating the Industry 4.0 readiness of enterprises’ human capital which demonstrates to be fast, adaptable and reusable
Photocatalytic hydrogen production by liquid- and gas-phase reforming of CH3OH over flame-made TiO2 and Au/TiO2
No full textTiO2 and 1% Au/TiO2 powders, synthesised by flame spray pyrolysis and possessing high specific surface area (106 m2 g 1) and anatase content (ca. 90%), were tested as photocatalysts in hydrogen production frommethanol photoreforming, employing a closed recirculation apparatus. The irradiated photoreactor consisted either in a quartz vessel containing an aqueous suspension of the photocatalyst, or in a newly set-up Plexiglas cell, containing the same amount of catalyst immobilised on quartz grains, which was continuously fed with methanol/water vapours. The gas-phase composition during irradiation was analysed by gas chromatography and quadrupolar mass spectrometry, which allowed the identification of formaldehyde as the only intermediate species. The photocatalytic activity of the flame-made materials was higher than that of commercial Degussa P25 TiO2 and of 1% Au/P25 obtained via deposition of preformed gold nanoparticles on P25. In particular, a 30 times higher photocatalytic hydrogen production was obtained upon gold addition to TiO2. Furthermore, a 30% higher reaction rate
was attained with the vapour phase reactor, i.e. in the absence of liquid-phase mass transfer rate limitations, ensuring the production of up to 10.2 mmol of H2 h- 1 g- 1, with an apparent photon efficiency of 6.3%
Influence of electron quantum confinement on the electronic response of metal/metal interfaces
No full textA simple and fast method for Named Entity context extraction from patents
No full textThe process of extracting relevant technical information from patents or technical literature is as valuable as it is challenging. It deals with highly relevant information extraction from a corpus of documents with particular structure, and a mix of technical and legal jargon. Patents are the wider free source of technical information where homogeneous entities can be found. From a technical perspective the approaches refer to Named Entity Recognition (NER) and make use of Machine Learning techniques for Natural Language Processing (NLP). However, due to the large amount of data, to the complexity of the lexicon, the peculiarity of the structure and the scarcity of the examples to be used to feed the machine learning system, new approaches should be studied. NER methods are increasing their performances in many contexts, but a gap still exists when dealing with technical documentation. The aim of this work is to create an automatic training sets for NER systems by exploiting the nature and structure of patents, an open and massive source of technical documentation. In particular, we focus on collecting the context where users of the invention appear within patents. We then measure to which extent we achieve our goal and discuss how much our method is generalizable to other entities and documents
Fujita modified exponent for scale invariant damped semilinear wave equations
No full textThe aim of this paper is to prove a blow-up result of the solution for a semilinear scale invariant damped wave equation under a suitable decay condition on radial initial data. The admissible range for the power of the nonlinear term depends both on the damping coefficient and on the pointwise decay order of the initial data. In addition, we give an upper bound estimate for the lifespan of the solution. It depends not only on the exponent of the nonlinear term and not only on the damping coefficient but also on the size of the decay rate of the initial data
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