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The impedance or admittance of an alternating-current circuit. It is sometimes convenient to use the term immittance when referring to a complex number which may be either the impedance (ratio of voltage to current) or the admittance (ratio of current to voltage) of an electrical circuit. The units of impedance and admittance are, of course, different and so units cannot be assigned to an immittance. However, in certain theoretical work it may be necessary to deal with general functions which afterward will be specialized to become either an impedance or an admittance by the assignment of suitable units; in such cases it is convenient to refer to the functions as immittances. See Admittance, Electrical impedance

McGraw-Hill Concise Encyclopedia of Physics. © 2002 by The McGraw-Hill Companies, Inc.


A term used to denote both impedance and admittance, as commonly applied to transmission lines, networks, and certain types of measuring instruments.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
In addition to the otorhinolaryngological evaluation procedures, acoustic immittance measures and TEOAE, all children were submitted to the investigation of the electrophysiological thresholds by air and bone pathways through the ASSR and the minimum levels of responses by air and bone pathways via VRA.
The aims of this study were to summarize the clinical manifestations and audiological characteristics of AN, to explore the roles of pure tone audiometry, acoustic immittance test, auditory brainstem response test and distortion product (DP) otoacoustic emission test in AN diagnosis, to investigate whether AN was complicated with vestibular function disorders or other nervous system diseases, and importantly, to provide valuable evidence for future clinical and experimental studies on AN.
Monitoring audiological evaluations during treatment and the one- and three-month follow-up evaluations include case interview, otoscopy, and immittance audiometry as well as air conduction pure tone and objective testing [73].
Kuntman, "Universal immittance function simulators using current conveyors," Computers and Electrical Engineering, vol.
[18] However, immittance audiometry, otoacoustic emissions, a comprehensive case history, behavioural observation, and functional hearing measures should all be conducted or at least attempted to supplement the ABR results.
A more definitive study would test patients' hearing, including the attainment of extended high frequencies (beyond 8000 Hz), measurement of otoacoustic emissions, immittance testing, and speech testing, before (baseline testing) and after they started using the medication.
Boukamp, "Linear Kronig-Kramers transform test for immittance data validation," Journal of the Electrochemical Society, vol.
Acoustic immittance measures; basic and advanced practice.
J., "A method for the computation of the characteristic immittance matrix of multiconductor striplines with arbitrary widths," IEEE Trans.
Roy, "On the realization of a constant-argument immittance or fractional operator," IEEE Transactions on Circuit Theory, vol.
All subjects had normal immittance audiometry results.
where [Y.sub.0] and [Y.sub.U] denote the terminating admittance and characteristic admittance of immittance inverters; [g.sub.i] are the element values of lowpass prototype; [[Ohm].sub.c] is the normalized cutoff frequency; [b.sub.i] and [DELTA][f.sub.3dBi] are the susceptance slop parameters and 3-dB bandwidths of the serials parallel resonators correspondingly; [L.sub.i] and [C.sub.i] are the equivalent inductances and capacitances of each resonator respectively.