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In this paper authors conduct a case study analysis by implementing the use of UAVs in the data collection within the BRAIN framework for the failures diagnosis of facades. The main goal is to assess the conditions and usefulness of UAVs in the BRAIN protocol by analyzing the goodness of fit to the fundamental requirements that support this inspection methodology. This preliminary qualitative approach allows the authors to investigate the benefits and potential of this high performance technology as a complement or alternative tool to the initial method, which is based on visual inspections supported, as maximum, by high resolution digital camera images. For the study a sample of facades has been selected in Poland. A full equipped UAV has been collecting the images. Finally, full procedure, collected data and positive and negative issues has been assessed under the perspective of the requirements involved in a multiscale BRAIN inspection. Overall scoring conditions has been determined and, as a conclusion, it can be stated that the use of UAVs for technical inspections in a population based predictive approach is, and even more it will be in the future, an interesting complementary tool for the data collection.

While generating high harmonics in long media of helium gas, at certain laser intensities and chirp, the spectral shift and split of the harmonic lines were experimentally observed, sometimes exceeding one harmonic order. Beyond reporting these results, numerical simulations were performed to understand the phenomenon. A 3D propagation model was solved under the strong field approximation. According to the simulations, the distortion of the laser beam profile during propagation and the consequently accused change in the conditions of phase matching are responsible for the observations. The observed phenomena can be an excellent tool to produce tunable narrow band harmonic sources covering a broad range around 13.5 nm for spectroscopy and for seeding X-ray lasers, and to understand non-desired detuning of the seed wavelength. [ABSTRACT FROM AUTHOR]

In the context of the existing buildings, in recent years the concept of maintenance has changed from corrective maintenance to preventive maintenance, which is based in part on periodic inspections. There is ample evidence that preventive maintenance is more efficient than corrective maintenance, since severe deteriorations that may represent danger to people are avoided, and also money is saved. To make periodic inspections of the buildings is useful to quantify the extent to which deteriorations are severe or not, in order to facilitate decision making and prioritise therapeutic interventions. To this purpose, many scales have been used and are used to assess the degree of severity of the deteriorations in constructive elements. But it is important to say that there is no common consensus and these scales are different between them according to the study to which they belong. Thus, the main goal of this article is to propose a methodology for calculating the degree of severity of damages in buildings, which is of widespread use. This calculation method, based on one hand in a distribution of values and on the other hand in a single value (scalar), lets to calculate the severity index of systems and of the entire building, and it is easy to use and flexible. [ABSTRACT FROM AUTHOR]

A study has been conducted to examine the case of a parabolic index guide combines with a Gaussian gain guide. The effective index method was used since the study initially assumes that the transverse variations of the electric permittivity of the amplifying medium are distributed over the length of the cavity and can be averaged over the axial coordinate.

A static electric field added at each spot of the interaction region controls high-order harmonic generation. The method is all-optical and susceptible to feedbackloop control schemes.