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Plasma thin-film deposition can be used to refurbish hydraulic turbine assemblies and subassemblies. In the case of reconditioning by the plasma jet deposition method, one or more plasma jet passes may be carried-out over the worn surface until the gaps achieved by the effect of the hydro-abrasive wear are filled with the depositing material. This paper presents the results obtained at the hardness tests of the thin layers deposited by plasma jet with powders based on Nickel and Boron (Deloro 60). Also, the adhesion of the multiple layers to the base material as well as the adhesion between the layers and the defects that appear on its separation surface were studied. The samples were also analysed from the point of view of the chemical composition by EDX probe and structurally by optical and electron microscopy Vickers-type micro-hardness tests were performed to determine the micro-hardness of the base material and the deposited layer. The VEGA II LMH electron microscope (TESCAN) with TAX QX2 EDX module was used to determine the material structure. The samples were obtained by the method of spraying in mesh spray with Ni powder. By this type of deposition, an easy method of obtaining and rectifying the blades of the hydraulic turbines is obtained with aims to harden the turbine’s blades, in order to increase the wear resistance without affecting the corrosion resistance.

The models designed CAD/CAM were loaded into the simulator to analyze the characteristics of the experimental devices attached. The array of sensors with unconventional architecture with reconfigurable unit cells (UCs) was topologically optimized, establishing the opening angle of the cell, the active surface, the geometry of the structure of the areas starting from the idea that the resonance frequency should be within the range of ISM frequencies. The simulations and determinations of test parameters of UC geometry are used for realization of arrays with reconfigurable shapes having the same aperture angle that can be used as wireless sensors for pressure detection.

Weigh-in-motion (WIM) sensors allow the control of vehicle weights without disruption of traffic. WIM systems bring very important savings by traffic monitoring and by reducing the number of overloaded vehicles. This paper discusses the present status and developmental trends of Haigh-speed weigh-in-motion (HS-WIM) technologies. Both commercial and new types of WIM sensors are presented. Strengths and weaknesses of different type of WIM sensors are discussed, as well as the economic aspects of the different technologies. Possible future developments of WIM technologies concerning the measurement performance are also described.

Mohr-Coulomb failure criterion is used to establish the failure conditions under a compound state of stress. According to this criterion, materials failure is produced to a certain combination of normal and shear stresses. Arcan type tests are an easy way to study the specimens behavior in pure and mixed mode (tensile & shear) respectively. The fixture allows an ARCAN sample to be rotated at 15° increments from 0° to 90° to produce different amounts of mode-mixt during loading; with 0° being pure tension/compression loading to 90° being pure shear loading. The Arcan method, like the Iosipescu method, uses specimens with a predetermined breaking section. A condition for material testing is that the stress in the narrow section to be as uniform as possible. This depends on the shape and depth of the notch. Starting from apriori knowledge about Iosipescu specimen, the modelling will be carried in FEM software to optimize the shape of the specimen, in order to obtain more uniform stress in cross section, A FEM is performed for Iosipescu specimen, designed for pure shear, when it is mounted in Arcan device, so it is need to be studied for some complex states of stress. The studied material is aluminum alloy type 7075, used in aerospace industry. This analysis is necessary before the tests are carried out, in order to adopt an appropriate form of the specimens.

The most common defects in turbine blades may be faulty microscopic and mesoscopic appeared in matrix, no detected by classical nondestructive testing (i.e. using phased array sensors), broken fibers can also appear and develop under moderated loads, or cracks and delaminations due to low energy impacts, etc. The paper propose to present the results obtained from testing of glass fiber reinforced plastic used in the construction of the wind turbine blades as well as the monitoring of the entire scalable blade using wireless sensors placed on critical location on blade. In order to monitories the strain/stress during the tests, the determination of the location and the nature of defects have been simulated using FEM.

Zinc oxide nanostructured materials, such as films and nanoparticles, could provide a suitable platform for development of high performance biosensing material due to their unique fundamental material properties. In this study, the enzyme biosensing consisting of a zinc oxide (ZnO) nanoparticles were grown on SiO2/Si substrates by vacuum thermal evaporation method and their sensing characteristics are examined in air and investigated. The film morphology is characterized by X-ray diffraction (XRD) the film crystalline quality and by scanning electron microscopy (SEM). Also, the interest in surface waves appeared due to evanescent waves in the metallic strip grating structure (MSG-Ag/ZnO/SiO2/Si) in sub-wavelength regime. Before testing the sensor with metamaterials (MMs) lens in the sub-wavelength regime, a simulation of the evanescent wave's formation has been performed at the edge of Ag strips, with thicknesses in the range of micrometers.