At NMIJ/AIST, there are two divisions in the electrical standards area. One is the Electricity and Magnetism (EM) Division and the other is the Electromagnetic Waves Division. The former covers low frequency electrical standards and the latter high frequency and electromagnetic field standards. The EM division has two sections, the Applied Electrical Standards Section and the Quantum Electrical...

A theoretical ac impedance model of biological tissue has been proposed after studying a cellular membrane using X-ray diffraction technique [1], a metal/organic system using ac impedance spectroscopy [2] and reviewing two pieces of literature of similar topics [3,4]. This paper emphasizes ac impedance techniques which can be used to study any heterogeneous materials in order to develop a lumpe...

Impedance biosensors are a class of electrical biosensors that show promise for point-of-care and other applications due to low cost, ease of miniaturization, and label-free operation. Unlabeled DNA and protein targets can be detected by monitoring changes in surface impedance when a target molecule binds to an immobilized probe. The affinity capture step leads to challenges shared by all label...

The purpose of this study is to provide a new approach for detection using bio-impedance. This impedance is measured by the four-electrode method. As the impedance changes resulting from ankle, knee, and hip movements depended heavily on electrode placement, we determined the optimal electrode configurations for those movements by searching for high correlation coefficients, large impedance cha...

The paper describes a fast and simple method to find the deviation of impedance of different tissues from the average values known from the literature. A technique similar to the Electrical Impedance Tomography is used assuming the geometry of organs to be known. To find the individual impedance deviations, we assume that the change of the surface potentials depends linearly on a small (up to 1...

The limited usefulness of the maximum power transfer theorem in practice is argued. Inappropriately, the utility and value of the maximum power transfer theorem are often elevated to be religious icons of electrical engineering. While the theorem appears to be useful, often in real circuits the load impedance is not set equal to the complex conjugate of the equivalent impedance of the connectin...

The measurement of the electrical impedance inside the esophagus provides information about its status, and is being explored in the study of the gastroesophageal reflux. This paper presents theoretical computation of impedance inside the esophagus. The results of the numerical solution for a simple geometry are compared against the solution formulated from the Green's function approach. The ef...