Shooting-Bouncing-Rays Technique to Model Mine Tunnels: Algorithm Acceleration

We present and discuss acceleration of a shooting and bouncing rays (SBR) algorithm for ray-tracing electromagnetic analysis of electrically very large structures such as underground mine tunnels at modern wireless communication frequencies. The acceleration is based on the parallelization of the SBR technique on NVIDIA GPUs using the OptiX application programming interface. The results show dramatic speedups of the parallel SBR algorithm compared with serial implementation.

Shooting-Bouncing-Rays Technique to Model Mine Tunnels: Theory and Accuracy Validation

We present a shooting-bouncing rays technique for electromagnetic modeling of wireless propagation in long tunnels focusing on the accuracy of ray-tracing computation. The examples demonstrate excellent agreement with the traditionally more accurate but less efficient alternative ray-tracing approach using path corrections based on image theory and with a commercial solver.

Autonomous Instrumentation for Measuring Spontaneous Electromagnetic Emissions in Mining

This article presents the design of an innovative receiver capable of identifying electric and magnetic components of electromagnetic fields. The receiver senses and records electromagnetic disturbances generated as mine tunnels collapse. It offers excellent operating specification and the ability to sense and log magnetic and electrical component strength values in real time. The paper analyzes the data obtained with the use of a system installed in a working mine and attempts to determine hazards resulting from increased rock stress levels that, cause spontaneous EM emissions.

Two decades of GPS/GNSS and DInSAR monitoring of Cardona salt mines (NE of Spain) – natural and mining-induced mechanisms and processes

Cardona area presents surface rising and subsidence active movements. In 1999 a series of sinkholes appeared due to the infiltration of Cardener River water into the mine tunnels, damaging surface infrastructures. Since then, high precision GNSS/GPS was used annually to position a network of 40 points spread over the area. GNSS/GPS work is carried out with the Fast-Static (FS) method. Additionally the surface movements have been monitored with satellite Differential Interferometry Synthetic Aperture Radar (DInSAR). Results indicate that the movement has a complex spatial distribution although consistent along time. Some areas show surface rising during the last two decades, while other areas show subsidence. The use of the two techniques allowed to determine the most plausible causes of these movements generated by a set of interwoven natural and human-induced complex processes.