Electrical resistivity tomography Electrical resistivity tomography Electrical resistivity tomography (ERT) or electrical resistivity imaging (ERI) is a geophysical technique for imaging sub-surface structures from electrical resistivity measurements made at the surface, or by electrodes in one or more boreholes. If the electrodes are suspended in the boreholes, deeper sections can be investigated. It is closely related to the medical imaging technique electrical impedance tomography (EIT), and mathematically is the same inverse problem. In contrast to medical EIT, however, ERT is essentially a direct current method. A related geophysical method, induced polarization (or spectral induced polarization), measures the transient response and aims to determine
Electrical Artificer closure 1998 an amount of EA's were trained in the Irish Army Apprentice School and transferred to the Naval Service on completion of training. Rank on completion of training is 'Able EA', followed by promotion based on experience and training to 'Leading EA', 'Petty Officer EA' and 'Chief Petty Officer EA'. The highest possible rank is 'Warrant Officer EA' of which there is only one in the Irish Naval Service Electrical Artificer An Electrical Artificer (EA) is an electrical technician competent in the electrical maintenance of ship's machinery such as engines and generators. This was originally a Royal Navy term