AS 3778.2.4-2001

1 - AS 3778.2.4-2001 MEASUREMENT OF WATER FLOW IN OPEN CHANNELS - GENERAL-ESTIMATION OF UNCERTAINTY OF A FLOW-RATE MEASUREMENT
4 - PREFACE
6 - CONTENTS
7 - 1 Scope
7 - 2 Normative references
8 - 3 Definitions and symbols
8 - 3.1 Definitions
8 - 3.1.1 correction:
8 - 3.1.2 coverage:
8 - 3.1.3 error:
8 - 3.1.4 estimate:
9 - 3.1.5 fossilization:
9 - 3.1.6 influence [sensitivity] coefficient:
9 - 3.1.7 observed value:
9 - 3.1.8 random error:
9 - 3.1.9 random uncertainty:
9 - 3.1.10 statistical quality control chart:
9 - 3.1.11 systematic error:
9 - 3.1.12 systematic uncertainty:
9 - 3.1.13 Taylor's series:
9 - 3.1.14 uncertainty:
9 - 3.1.15 uncertainty interval:
9 - 3.1.16 Welch-Satterthwaite method:
9 - 3.1.17 working standard:
10 - 3.2 Symbols
10 - Symbol
12 - Subscripts
12 - 4 General principles of measurement uncertainty analysis
12 - 4.1 Nature of errors
12 - 4.2 Random error
14 - 4.3 Systematic error
14 - 4.4 Spurious errors
15 - 4.5 Combining elemental uncertainties
15 - 4.6 Uncertainty of measurements
16 - 4.7 Propagation of measurement uncertainties to test result uncertainties
16 - 4.8 Uncertainty analysis before and after measurement
17 - 5 Identification and classification of elemental measurement error sources
17 - 5.1 Summary of procedure
17 - 5.2 Systematic versus random
18 - 5.3 Categorization of elemental error sources
18 - 5.4 Calibration error sources
19 - 5.5 Data acquisition error sources
20 - 5.6 Data reduction error sources
20 - 5.7 Method error sources
20 - 5.8 Subjective error sources
20 - 6 Estimation and presentation of elemental uncertainties
20 - 6.1 Summary of procedure
21 - 6.2 Calculation of experimental standard deviation
21 - 6.3 Estimation of systematic uncertainty
22 - 6.4 Final uncertainty classification based on the defined measurement process
22 - 6.4.1 Long versus short-term testing
22 - 6.4.2 Comparative versus absolute testing
23 - 6.4.3 Averaging to reduce random error
23 - 6.5 Example of uncertainty classification: a calibration constant
24 - 7 Combination and propagation of uncertainties
24 - 7.1 Summary of procedure
25 - 7.2 Combining elemental experimental standard deviations
25 - 7.3 Combining elemental systematic uncertainties
26 - 7.4 Propagation of measurement uncertainties
27 - 8 Calculation of uncertainty
27 - 8.1 Summary of procedure
27 - 8.2 Uncertainty intervals
28 - 8.3 Symmetrical intervals
28 - 8.4 Nonsymmetrical interval
29 - 9 Presentation of results
29 - 9.1 Summary of requirement
30 - 9.2 Before-measurement analysis and corrective action
30 - 9.3 After-measurement analysis and data validity
31 - 9.4 Summary for reporting error
31 - 9.5 Reporting uncertainty: Table of elemental sources