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This paper reports on the assessment of the underground construction details of a road pavement using different frequency ground penetrating radar (GPR) antenna systems. In addition to this, the possible presence and location of an underground watercourse was investigated in this work. The existence of the latter problem was perceived due to reoccurrence of longitudinal and traversal road surface...
This study reports on an investigation into the grain size distribution of the railway ballast using ground-penetrating radar (GPR) and image analysis. The proposed approach relies on the hypothesis that the dimension (grading) of the ballast aggregates can influence the back-reflected spectrum received by the use of GPR. This assumption was confirmed by the finite difference time-domain (FDTD) simulations...
As distributed energy resources become more common and complexity rises in power systems, robust distributed solutions for problems related to electric energy are required. This work presents an innovative control scheme for UPS-style systems comprised of a back-to-back converter and a diesel generator set, without the need of communication links between converter and generator, by means of droop...
Ballast material typically employed in rail track bed construction has been herein physically and electromagnetically characterized. Several ground-penetrating radar (GPR) tests have been carried out in a laboratory environment, wherein a proper set-up was realized. Four GPR systems comprising five different central frequencies of investigation have been used for the measurements. The impacts brought...
In this work, the evolution of damages in pavement life cycle relative to rutting has been modeled in relevant pavement sections. Ground-penetrating radar (GPR) surveys were carried out at the rural road network scale using an air-launched pulsed radar system, 1GHz central frequency of investigation, linked to an instrumented van for collecting data at traffic speed. Surveys were performed in two...
Ground Penetrating Radar (GPR) has proved to provide a high reliability in detecting several subsurface features such as water and gas pipes, energy and telecommunication supplies, water reservoirs or air voids. The present work uses a comparison between different central frequencies of investigation to reconstruct the network of utilities located underneath a paved surface and to understand the best...
In this work a numerical model capable to predict the electromagnetic response of railway ballast aggregates under different physical conditions has been calibrated and validated by a simulation-based approach. The ballast model is based on the main physical and geometrical properties of its constituent material and it is generated by means of a random-sequential absorption (RSA) approach. A finite-difference...
The High-Luminosity phase of the Large Hadron Collider at CERN (HL-LHC) poses stringent requirements on calorimeter performance in terms of resolution, pileup resilience and radiation hardness. A tungsten-CeF3 sampling calorimeter is a possible option for the upgrade of current detectors. A prototype, read out with different types of wavelength-shifting fibers, has been built and exposed to high energy...
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