ISO 13909-1:2016 無煙炭とコークス—機械的サンプリング—パート1：一般的な紹介 | ページ 5

3.1

air-drying

process of bringing the moisture content of the sample (3.31) near to equilibrium with the atmosphere in the area in which further reduction and division of the sample are to take place

Note 1 to entry: Air-drying to equilibrium with the atmosphere applies to coal. Drying of coke is generally to facilitate sample preparation (3.34) .

3.2

bias

systematic error (3.10) which leads to the average value of a series of results being persistently higher or persistently lower than those which are obtained using a reference sampling method

3.3

coefficient of variation

standard deviation (3.37) expressed as a percentage of the absolute value of the arithmetic mean

3.4

common sample

sample (3.31) collected for more than one intended use

3.5

continuous sampling

taking of a sample (3.31) from each consecutive sub-lot (3.39) so that increments are taken at uniform intervals whenever the fuel is handled at the point of sampling

3.6

cut

see increment (3.15)

3.7

cutter

mechanical sampling device which extracts increment(s)

3.8

divided increment

part obtained from the division of the increment in order to decrease its mass

Note 1 to entry: Such division may be done with or without prior size reduction.

3.9

duplicate sampling

particular case of replicate sampling (3.30) with only two replicate samples (3.31)

3.10

error

difference between the observation and the accepted reference value as defined in ISO 5725-1:1994, 3.5

Note 1 to entry: This can be designated as systematic error [ bias (3.2) ] or random error (3.29) .

3.11

fixed mass division

method of sample division (3.33) in which the mass retained is predetermined and independent of the mass of the feed

3.12

fixed ratio division

method of sample division (3.33) in which the division ratio is predetermined

Note 1 to entry: In fixed ratio division, the mass of sample (3.31) retained is a fixed proportion of the mass of the feed.

3.13

fuel

hard coal or coke

3.14

general-analysis test sample

sample (3.31) , prepared to pass a sieve of nominal size of openings 212 µm complying with ISO 3310-1, used for the determination of most chemical and some physical characteristics

3.15

increment

portion of fuel (3.13) extracted in a single operation of the sampling device

3.16

lot

defined quantity of fuel (3.13) for which the quality is to be determined

Note 1 to entry: A lot may be divided into sub-lots (3.39) .

3.17

manual sampling

collection of increments (3.15) by human effort

3.18

mass-basis sampling

taking of increments (3.15) whereby the position of each increment to be collected from the stream of fuel (3.13) is measured by a mass interval of stream flow and the increment mass is fixed

3.19

mechanical sampling

collection of increments (3.15) by mechanical means

3.20

mechanical sampling system

combination of sampling and sample preparation (3.34) performed mechanically

3.21

moisture sample

sample (3.31) taken specifically for the purpose of determining total moisture

Note 1 to entry: For coke, this sample may also be used for general analysis.

3.22

nominal top size

aperture size of the smallest sieve in the range included in the R 20 Series (as defined in ISO 565, square hole) on which not more than 5 % of the sample (3.31) is retained

3.23

off-line sample preparation

sample preparation (3.34) performed manually or mechanically on the samples (3.31) produced by the mechanical sampling system (3.20) , using equipment not integral to the mechanical sampling system itself

3.24

on-line sample processing

processing of the primary sample (3.31) material using equipment integral with the sampling system

3.25

outlier

result which meets statistical criteria identifying an outlier, esp. exceeding Cochran’s maximum variance test, and for which there is direct physical evidence of causation by gross deviation from the prescribed experimental procedure

3.26

physical sample

sample (3.31) taken specifically for the determination of physical characteristics, such as physical strength indices or size distribution

3.27

precision

closeness of agreement between independent test results obtained under stipulated conditions

Note 1 to entry: This is often defined using an index of precision, such as two standard deviations (3.37) .

3.28

primary increment

increment (3.15) taken at the first stage of sampling, prior to any sample division (3.33) and/or sample reduction (3.35)

3.29

random error

error (3.10) that is statistically independent of previous errors

Note 1 to entry: This implies that any two errors in a series of random errors are uncorrelated and that individual errors are unpredictable. In consequence of the partitioning of error into systematic [ bias (3.2) ] and random components, the theoretical mean of the random errors is zero. Whereas individual errors are unpredictable, the mean of the random errors in a series of observations tends towards zero as the number of observations increases.

3.30

replicate sampling

taking at intervals of increments (3.15) which are combined in rotation into different containers to give two or more samples (3.31) of approximately equal mass

3.31

sample

quantity of fuel (3.13) , representative of a larger mass for which the quality is to be determined

3.32

sampler

device physically collecting a sample increment (3.15)

Note 1 to entry: Not to be confused with personnel physically collecting an increment or operating a sampling system.

3.33

sample division

process in sample (3.31) preparation whereby the sample is divided into representative, separate portions

3.34

sample preparation

process of bringing samples (3.31) to the condition required for analysis or testing

Note 1 to entry: Sample preparation covers mixing, particle size reduction, sample division (3.33) and sometimes air-drying (3.1) of the sample and may be performed in several stages.

3.35

sample reduction

process in sample preparation (3.34) whereby the particle size of the sample (3.31) is reduced by crushing or grinding

3.36

size analysis sample

sample (3.31) taken specifically for particle size analysis

3.37

standard deviation

square root of the variance (3.43)

3.38

stratified random sampling

taking of an increment (3.15) at random within the mass interval or time interval determined for mass-basis sampling (3.18) or time-basis sampling (3.42) , respectively

3.39

sub-lot

part of a lot (3.16) for which a test result is required

3.40

systematic sampling

taking of increments (3.15) at uniform mass or time intervals according to a predetermined plan

3.41

test sample

sample (3.31) which is prepared to meet the requirements of a specific test

3.42

time-basis sampling

taking of increments (3.15) whereby the position of each increment to be collected from the stream of fuel (3.13) is measured by a time interval and the increment mass is proportional to the flow rate at the time the increment is taken

3.43

variance

measure of dispersion, which is the sum of the squared deviations of observations from their average divided by one less than the number of observations