In magnetic resonance electrical impedance tomography (MREIT) we inject currents through electrodes placed on the surface of a subject and try to reconstruct cross-sectional resistivity (or conductivity) images using internal magnetic flux density as well as boundary voltage measurements. In this paper we present a static resistivity image of a cubic saline phantom (50 x 50 x 50 mm3) containing...

PURPOSE To investigate the usefulness of transcranial Doppler ultrasonography in the evaluation of intracranial pressure changes after head injury. METHODS Transcranial Doppler examinations and intracranial pressure measurements using intraparenchymal monitors were performed in 12 cases of closed head injury. Twenty-four sets of data, including the Glasgow Coma Scale, intracranial pressure, t...

The optimal design of production in fractured geothermal reservoirs requires knowledge of the resource’s connectivity, therefore making fracture characterization highly important. This study aims to develop methodologies to use resistivity measurements to infer fracture properties in geothermal fields. The resistivity distribution in the field can be estimated by measuring potential differences...

We studied resistivity, magnetoresistivity, and Hall resistivity for a few percolating granular NiFe-SiO2 films upon thermal annealing. It was found that both the resistivity and the Hall resistivity decrease by two orders of magnitude upon annealing at 520 °C, accompanied by a crossover from an approximately 2lnT dependence of resistivity to a metallic behavior. On the other hand, transmission...

Investigations over two major tectonic zones in the Hallandsås Horst, Southern Sweden were carried out in connection with a railway tunnelling project. A combination of resistivity imaging, core drilling and geophysical logging was found to provide a good overview of the variation in rock quality and detailed information on the engineering geological characteristics and genesis of the strata. R...

Reinforced concrete used for bridge decks and pillars, highways and other transportation facilities experience loss of integrity over time caused by poor initial quality, action of de-icing salts, temperature changes, fatigue and, above all, delamination caused by corrosion of reinforcement bars (rebars for brevity). Electrical resistivity is sensitive to those losses of integrity. Using 3D num...

Electrical Resistivity Tomography (ERT) is increasingly used to investigate moisture distribution in Municipal Waste Landfills, especially when leachate is injected in waste to enhance its biodegradation. It is proposed here to theoretically assess the quality of ERT mapping, using COMSOL Multiphysics' simulations of both hydrodynamical and geophysical aspects. Leachate injection is simulated u...

two dimensional single frequency scalar vlf data modeling has been studied in this research. vlf method is one of the electromagnetic investigation methods. radio frequency waves are used for investigation of conductive deposits (paal, 1968). synthetic modeling and inversion of single frequency and multiple frequencies of vlf signals was done by oskooi (2004) for two dimensional simple structur...

introduction: occurrence of landslides depends on several factors such as the composition and structure of earth materials, rainfall level, temperature, groundwater regime and cover crops. landslides are a main natural hazard in iran, because of its special geological conditions and its mountainous active tectonic regime. linear civil structures, such as roads, highways and railways, face serio...

Bacterial sensitivity and resistivity to any antibiotic tends to undergo temporal fluctuations. The clinical consequence of such behaviour is reduced effectiveness of a particular antibiotic to treat a specific bacterial infection. The forecasting system described in this paper uses a backpropagation neural network to model time series derived from bacteria-antibiotic sensitivity and resistivit...