Comparison Measurement

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Comparison Measurement


the general name of measurement methods in which the quantity measured is compared with a quantity reproduced by a standard.

Comparison measurement includes (1) the opposition method, in which two quantities—the measured quantity and the quantity reproduced by the standard—act simultaneously on a comparison device, as in measuring a weight on a balance, (2) the difference method, in which the difference between quantities acts on a comparison device, for example, in comparing the lengths gage blocks on an interferometer, (3) the null method, in which the resultant effect of the comparison is zero, for example, in measuring resistance by means of a DC bridge with complete balancing, (4) the substitution method, in which the measured quantity is replaced by a quantity reproduced by the standard, for example, in weighing a body by alternately placing the body and weights on the same pan of a balance, and (5) the coincidence method, in which the difference between quantities is measured by the coincidence of marks on scales or of signals, as indicated, for example, by a vernier or stroboscope.

Comparison measurement is applicable to quantities that can be reproduced by standards. This method usually affords greater precision than indirect measurement because the error of the result is chiefly determined by the insignificant error of the standard, and the residual errors can be kept to low values.


Burdun, G. D., and B. N. Markov. Osnovy metrologii. Moscow, 1972.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
A lattice comparison measurement involving the silicon material from SERI is included in the 2014 CODATA recommended values of the fundamental physical constants, where the material is called ILL [15].
The display can be zeroed at any position, making comparison measurement easier.
The participation in this international comparison measurement was representing a real validation of the device and evaluated measurement uncertainty.
The comparison measurement is to be made at signal frequencies that show amplitudes close to the applicable limit in quasipeak detection.
GE's Ca-Zoom 6.2 puts inspection and digital image management in the palm of your hand with three interchangeable camera head options, integrated image capture, full-motion video recording capabilities and comparison measurement features.
Multimeter Metex M-3860M was used for the comparison measurement. The effective values [U.sub.OUT(RMS)] from AD637 and M-3860M were compared with the theoretical value.
Standardization/ recalibration makes sense only when sufficient correlation of the investigated immunoassay is achieved with the comparison measurement procedure (or sufficient specificity).
Gages are used in conjunction with electronic or dial indicators for comparison measurement or interfaced with data-collection software.
The 10 kV reference techniques at NIST are generally only used for comparison measurement work at NIST and rarely requested for routine calibrations.
In this comparison measurement, the neutral [.sup.3]He atom is assumed to have a negligible electric dipole moment.
The complete comparison measurement routine was conducted at least twice for each of the NIST standards.

Full browser ?