This is a history of commercial instruments that measure impedance from the 1930s to the present day. It concentrates on general-purpose and production-test bridges and meters that measure resistance, capacitance and inductance at low frequencies. It intends to show how electronics has changed these electrical measurements just as it changed all other technologies.

If electrical impedance tomography is to be used as a clinical tool, the image reconstruction algorithms must yield accurate images of impedance changes. One of the keys to producing an accurate reconstructed image is the inclusion of prior information regarding the physical geometry of the object. To achieve this, many researchers have created tools for solving the forward problem by means of ...

One unfortunate occurrence in experimental measurements with electrical impedance tomography is electrodes which become detached or poorly connected, such that the measured data cannot be used. This paper presents an automatic approach to detect such erroneous electrodes. It is based on the assumption that all valid measurements are related by the image reconstruction model, while the measureme...

A variational method is given for determining the essential supremum of the surface impedance of a partially coated perfect conductor from a knowledge of the far field pattern of the time-harmonic electric field at fixed frequency. It is assumed that the shape of the scatterer has been determined (e.g., by solving the far field equation and using the linear sampling method). Numerical examples ...

We review modelling and experimental work dealing with the mechanisms of generation of electric image. We discuss: (1) the concept of electric image in the context of the reafference principle; (2) how waveform codes an impedance related qualia of the object image, referred to as "electric colour"; (3) that some characteristics of the spatial profiles generated by pre-receptor mechanisms are su...

An alternative representation of a Green’s function for electric fields on surfaces of thin impedance vibrators is proposed. The representation can be applied in software packages for simulation of RF and microwave devices. Advantages of the approach were demonstrated by analyzing the wellknown problem of a thin symmetrical horizontal vibrator above a perfectly conducting plane. For a half-wave...

This paper investigates wave-based analysis and impedance matching for the ladder electric networks. The results are a generalized version of our previous work for the cascade connected damped mass-spring systems. We first clarify the class of the ladder networks which satisfies the three conditions for the propagation constants to be analyzed by the wave-based analysis. Secondly, for the class...

Magnetic resonance electrical impedance tomography (MREIT) measures magnetic flux density signals through the use of a magnetic resonance imaging (MRI) in order to visualize the internal conductivity and/or current density. Understanding the reconstruction procedure for the internal current density, we directly measure the second derivative of Bz data from the measured k-space data, from which ...

Electrical impedance is not a scalar but a complex quantity. Thus, evaluation of the uncertainty of its value involves a model whose output is a complex. In this paper the comparison of the evaluation of the uncertainty of the measurement of the electrical impedance of a simple electric circuit using the GUM and using a Monte Carlo method according to the Supplement 2 of the GUM is presented.

We consider the inverse problem of finding cavities within some body from electrostatic measurements on the boundary. By a cavity we understand any object with a different electrical conductivity than the background material of the body. We survey two algorithms for solving this inverse problem, namely the factorization method and a MUSIC-type algorithm. In particular, we present a number of nu...