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The Cherenkov Telescope Array (CTA) is a future instrument for very-high-energy (VHE) gamma-ray astronomy that is expected to deliver an order of magnitude improvement in sensitivity over existing instruments. In order to meet the physics goals of CTA in a cost-effective way, Monte Carlo simulations of the telescope array are used in its design. Specifically, we simulate large arrays comprising numerous large-size, medium-size and small-size telescopes whose configuration parameters are chosen based on current technical design studies and understanding of the costs involved. Subset candidate arrays with various layout configurations are then selected and evaluated in terms of key performance parameters, such as the sensitivity. This is carried out using a number of data analysis methods, some of which were developed within the field and extended to CTA, while others were developed specifically for this purpose. We outline some key results from recent studies that illustrate our approach to the optimization of the CTA design. [ABSTRACT FROM AUTHOR]

In the present work numerical-experimental analysis for the characterization of a structural adhesive has been performed. The numerical analysis has been carried out through the finite element method by using, for the phases pre / post processing were used commercial programs while for the phase of numerical solution the Abaqus code was used. The experimental analyses were carried out at laboratories of C.R.F. S.C.p.A. by using of a standard quasi static testing machine. Later numerical analysis was performed comparing the torsional stiffness of a vehicle in which the welded connection between the pavilion and the flank has been substituted by bonded one. This comparison has allowed to demonstrate the ability of the bonded joint discussed to provide mechanical performances comparable with those of a welded joint widely used in the automotive industry. [ABSTRACT FROM AUTHOR]

In supersonic expansion flows of humid nitrogen, at relatively low cooling rates, self-sustained oscillations may occur due to the combined effects of nucleation, droplet growth, and latent heat release. Different modes of oscillation are found depending on the initial humidity. It is shown numerically that the stability limit and the oscillation frequencies of the different modes strongly depend on the nucleation rate. Numerical results are compared with experiments of Adam and Schnerr and own experiments for nozzles of different shapes. The ICCT nucleation model yields correct results for both series of experiments, when corrected with a factor of the order of 0.01. [ABSTRACT FROM AUTHOR]

The Cherenkov Telescope Array (CTA) [1] will be the successor to current Imaging Atmospheric Cherenkov Telescopes (IACT) like H.E.S.S., MAGIC and VERITAS. CTA will improve in sensitivity by about an order of magnitude compared to the current generation of IACTs. The energy range will extend from well below 100 GeV to above 100 TeV. To accomplish these goals, CTA will consist of two arrays, one in each hemisphere, consisting of 50-80 telescopes and composed of three different telescope types with different mirror sizes. It will be the first open observatory for very high energy γ-ray astronomy. The Array Control working group of CTA is currently evaluating existing technologies which are best suited for a project like CTA. The considered solutions comprise the ALMA Common Software (ACS), the OPC Unified Architecture (OPC UA) and the Data Distribution Service (DDS) for bulk data transfer. The first applications, like an automatic observation scheduler and the control software for some prototype instrumentation have been developed. [ABSTRACT FROM AUTHOR]

Carbon fibre reinforced polymers (CFRP) composite materials are widely used in mechanics. The joints between one metal plate with composite one are widely used in the same way and in many cases are the critical point of the whole structure as a result of the physical discontinuity between the parts, the stress concentrations developing around the joint area, and surface manufacturing of the parts. This work is focussed on the influence of both manufacturing and numerical modelling parameters on the structural behaviour of a hybrid mechanical coupling. Numerical models have been built and tested; the results have been compared with experimental ones. Afterwards numerical analyses have been performed to evaluate the influence of such above mentioned parameters on the structural behaviour of hybrid joints. Numerical analyses have been performed using Abaqus/Standard® numerical code. [ABSTRACT FROM AUTHOR]