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
Special measures the action plan has been completed and all points satisfactorily addressed, then they will refer the school back to Ofsted and ask them to schedule a second Section 5 Inspection. If Ofsted agree with HMI’s judgement, the school is then removed from the special measures category. It is worth noting that during an Inspection an HMI can change the nature of the Inspection to a Section 5, and remove the school from Special Measures upon completion. Support for schools that enter special measures comes in a variety of forms, and varies from local authority to local authority. Typically though schools