Metering accuracy

The required metering accuracy should be specified precisely and at a realistic value. In some instances, absolute accuracy is less important than long-term repeatability. When the error limit is given as a percentage, it... 

A precision pH-meter (accuracy of 0.005 pH units) and a glass and calomel reference electrode calibrated against pH standards were used to measure pH values (activity units) which were converted into - logio [H ] using the Debye-Hiickel equation. However, the absolute accuracy that can be achieved with the applied electrode calibration is at best +0.02 pH-units, which is not sufficient for the determination of accurate results from potentiometric titration data. This problem becomes evident from the results shown in Table 1 of [1971K1C/STE]. The value of = 0.5 was reached at pH = (3.00 + 0.05) in titrations starting at initial acid concentrations below 0.01 M (/ = 0.013-0.016 M) and at pH = (3.40 + 0.05) in titrations starting at initial acid concentrations of about 0.03 M (/ = 0.037 M). 

The interest in our metering accuracy can better be understood if you look at our gas rates. In 1974, they were 7 per million BTU, or 700 per therm, at the residential level and 5.30 per million BTU, or 530 per therm, at the commercial level. In addition, the SNG Plant was incorporated as a separate entity, selling all of its output to GASCO for distribution to its customers thus, unaccoimted for gas became a GASCO problem but was very much dependent on the accuracy of our meter. It seemed easier at the time to say The SNG plant s meter was inaccmate than to admit there were leaks in the distribution system. 

If the LPG was not fully vaporized, what effect did the droplets have on the turbine meter accuracy, blades, and bearings ... 

The next step was to develop a new standard of comparison forjudging meter accuracy. The SNG Plant has a theoretical mass balance equation that reduces to the following ... 

One of the few standards for cover meters is BS 1881 Part 204. This refers to the measurement on a single rebar. A useful paper has been published which discusses cover meter accuracy when several rebars are close together (Alldred, 1993). The paper suggests that different types of head are more accurate in different conditions. The smaller heads are better for resolving congested rebars. 

Alldred, J.C. (1993). Quantifying the Losses in Cover-meter Accuracy Due to Congestion of Reinforcement. Proc. 5th Inti. Conf. on Structural Faults and Repair, 2 125-130. 

The figure shows a step function until convergence is reached after about 5 minutes. This is due to the algorithm used which may be in favour of a certain ambiguity combination for some time until enough information forces it to reject the solution and to select a new one. The figure shows that half a meter accuracy is reached after about 90 seconds and centimeter accuracy is reached with 5 minutes of data. The noise in solutions after the fifth minute is in the 1-2 cm level. 

Bean, H.S. (1947). Indications of an orifice meter. American Gas Association Monthly 29 337. Bean, H.S. (1960). Effect of pipe roughness on orifice meter accuracy. American Gas Association New York. 

In preparing compounds with FR content, it is necessary to achieve a certain metering accuracy, if the main polymer resin has not already been purchased as an FR grade. Uniform dispersion of the FR additives is also most important for coat efficiency. The percentages added may fluctuate from quite low levels to very high ones for inorganic, dependant upon the required level of FR performance and the type of polymer used. 

Alldred, ).C. (1W3) Quantifying the losses in cover-meter accuracy due to cfjngestion of reinft rcement, Proceedings of the Fifth International Conference on Structural Faidts and Repair, Vt>l. 2 Engineering Technics Press, Edinburgh, pp. 125-30. 

The word relative applies to the accuracy of the standard buffer solution, the proper working electrodes, and the use of proper technique. Meter accuracy alone is not a significant specification since an entire system is involved in the measurement. The accuracy of entire system, however, depends on the many options available to the users, and the specifications which the manufacturer states are often only for the meter. The meter accuracy can be tested to obtain its magnitude and verify that it is not adding significant error. The steps involved in this test are ... 

Klonoff DC (2014) Point-of-Care blood glucose meter accuracy in the hospital setting. Diabetes Spectr 27(3) 174-179... 

Tenderich A (2014) Glucose meter aceuracy FDA s new dual eall for tighter standards., http //www.healthline.com/diabelesmine/glucose-meter-accuracy-fdas-new-dual-call-for-tig hter-standards 1... 

American Association of Diabetes Educators (2013) Survey to gauge knowledge regarding blood glucose meter accuracy. https //www.diabeteseducator.org/docs/default-sourceAeg acy-docs/ resources/advocacy/executive summary meter acc 2014.pdf sfvrsn=2... 

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