Fertilizers mineral

6 Near infrared spectroscopy method
LCL is missing.
The limits of action UCL and LCL1) are calculated by the formula
6.1 Measurement ranges and error characteristics of the results of measurements of the
mass fraction of moisture
where 1.96 is the distribution quantile at P= 0.95.
UCL \u003d D2 (2) og \ u003d 2.834 og
GOST 8.613-2012
5.8.3.4 Filling in and interpretation of Shewhart's control charts When
constructing Shewhart's control charts, the result of the control procedure is plotted along the ordinate axis w
- when implementing the control of the repeatability stability, ÿ - when implementing the control of the stability of the
error; the date of the analysis is plotted along the abscissa. A possible violation of the stability of the process of
measuring the mass fraction of moisture is evidenced by the appearance on the control chart of at least one of the
following features: one point went beyond the limits of action; all points in a row are on the same side of the midline;
six increasing (decreasing) points in a row. In this case, it is necessary to check compliance with the storage
conditions for samples prepared for the analysis of mineral fertilizers, sample preparation and measurements, as
well as the operating conditions of the IKTG moisture meter.
where n is the number of parallel definitions.
(13)
Vn
foot two.
5.8.3.3 Parameters of Shewhart control charts for error stability control To calculate the parameters
of control charts for control of calculation error stability
yut standard deviation of the error a according to the formula
In formulas (11) and (12), the coefficients 0 2 are given for the number of parallel determinations equal to
LCL = 12.
(14)
Warning Limits:
6.1.1 The method of NIR spectroscopy provides measurement results of the mass fraction of moisture in
mineral fertilizers and middlings with relative errors, the values of which do not exceed those indicated in Table 2.
(12)
UCL^fn
Machine Translated by Google

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chiv the number of points for calibration to reduce the error in the construction of the GC moisture meter.