In many acoustic simulations, particularly when using lumped parameter models or electrical analog circuits, the acoustic impedance of a component needs to be determined accurately. A widely used acoustic impedance measurement method is the ”two microphone transfer function method”, which is standardized in ISO-10534-2. When the acoustic impedance is needed over a wide frequency band with a hig...

Under the alternating electrical excitation, biological tissues produce a complex electrical impedance which depends on tissue composition, structures, health status, and applied signal frequency, and hence the bioelectrical impedance methods can be utilized for noninvasive tissue characterization. As the impedance responses of these tissue parameters vary with frequencies of the applied signal...

Frequency-difference electrical impedance tomography (fdEIT) reconstructs frequency-dependent changes of a complex impedance distribution. It has a potential application in acute stroke detection because there are significant differences in impedance spectra between stroke lesions and normal brain tissues. However, fdEIT suffers from the influences of electrode-skin contact impedance since cont...

Regional cerebral blood flow and blood volume changes that occur during human brain activity will change the local impedance of that cortical area, as blood has a lower impedance than that of brain. Theoretically, such impedance changes could be measured from scalp electrodes and reconstructed into images of the internal impedance of the head. Electrical Impedance Tomography (EIT) is a newly de...

Waterborne Epoxy based coatings were prepared by using a water-borne epoxy resin and a suitable hardener. The formulation and optimization procedure were carried out on the bases of experimental designs by the mixture design technique in which the important paint properties are modeled by using special cubic model. The corrosion behavior of these coatings was investigated using electrochemical ...

This paper discusses the effect of load change on the Thevenin equivalent impedance of power systems. In this paper, the Thevenin equivalent impedance influenced by the derivative of active load with respect to reactive load (dP/dQ) is analyzed. The Thevenin equivalent impedance forms a closed curve in a complex plane and shrinks to one point when voltage collapses. The magnitude of the Theveni...

This paper examines human impedance perception ability during manipulation of an impedance-controlled robot, especially as regards perception accuracy and differential limen. In the experiments, a subject is instructed to move the handle of an impedance-controlled robot and to perceive the presented value of the robot impedance. Experimental results show that both motor control ability and soma...

Biological organisms and their component organs, tissues and cells have unique electrical impedance properties. Impedance properties often change with changes in structure, composition, and metabolism, and can be indicative of the onset and progression of disease states. Over the past 100 years, instruments and analytical methods have been developed to measure the impedance properties of biolog...

The principle of numerically modeling the surface impedance of a homogeneous transverse magnetic (TM)-type plane wave incident upon an inhomogeneous half-space with inclined uniaxial electrical anisotropy as an equivalent half-space with fundamental electrical biaxial anisotropy is demonstrated. The self-consistent impedance method is introduced and shown to accurately model the surface impedan...

This article reviews recent developments in microfluidic impedance flow cytometry for high-throughput electrical property characterization of single cells. Four major perspectives of microfluidic impedance flow cytometry for single-cell characterization are included in this review: (1) early developments of microfluidic impedance flow cytometry for single-cell electrical property characterizati...