1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ICS 03.120.30 ISBN 0-626-17067-2 SANS 11648-1:2005Edition 1ISO 11648-1:2003Edition 1SOUTH AFRICAN NATIONAL STANDARD Statistical aspects of sampling from
4、bulk materials Part 1: General principles This national standard is the identical implementation of ISO 11648-1:2003, and is adopted with the permission of the International Organization for Standardization. Published by Standards South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0
5、001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 11648-1:2005 Edition 1 ISO 11648-1:2003 Edition 1 Table of changes Change No. Date Scope Abstract Establishes the general principles for the application and statistical treatment of the sa
6、mpling of bulk materials. It also provides general guidance and examples for estimating necessary variances and checking precision and bias when the average value of a quality characteristic is investigated. It gives information relating to the statistical analyses of serial data, by the use of vari
7、ograms and correlograms. It also defines the basic terms with definitions for the sampling of bulk materials. These terms are necessary for providing a better understanding of sampling techniques as well as making it easier to fulfil requirements. Keywords bulk goods, bulk materials, bulk products,
8、definitions, general section, material behaviour, premixed materials, samples, sampling, sampling methods, specimen preparation, statistical analysis, statistical methods of analysis, statistics, test specimens. National foreword This South African standard was approved by National Committee StanSA
9、TC 169, Applications of statistical methods, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. Reference numberISO 11648-1:2003(E)ISO 2003INTERNATIONAL STANDARD ISO11648-1First edition2003-03-15Statistical aspects of sampling from bulk mate
10、rials Part 1: General principles Aspects statistiques de lchantillonnage des matriaux en vrac Partie 1: Principes gnraux ISO 11648-1:2003(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be ed
11、ited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a
12、trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member b
13、odies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO 2003 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechan
14、ical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.
15、org Published in Switzerland ii ISO 2003 All rights reservedISO 11648-1:2003(E) ISO 2003 All rights reserved iiiContents Page Foreword iv Introduction v 1 Scope 1 2 Normative references . 1 3 Terms, definitions, symbols and abbreviated terms. 1 4 Purpose and application of statistics in sampling fro
16、m bulk material 11 5 Particular problems for sampling bulk materials 11 6 Differences between particulates, liquids and gases . 13 7 Experimental methods for obtaining variance components at various stages of sampling 14 8 Adjusting the sampling plan to obtain desired precision. 19 9 Estimating prec
17、ision. 20 10 Checking for bias 20 11 Precision and bias at measurement stage . 22 Annex A (informative) Explanatory notes on definitions . 23 Annex B (informative) Fully-nested experiments 28 Annex C (informative) Statistical analysis of serial data 36 Annex D (normative) Estimating precision 74 Ann
18、ex E (normative) Checking for bias . 78 Bibliography . 91 ISO 11648-1:2003(E) iv ISO 2003 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is
19、normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part
20、in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to pre
21、pare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that
22、some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 11648-1 was prepared by Technical Committee ISO/TC 69, Applications of statistical methods. ISO 11648 consists of the following parts, under
23、 the general title Statistical aspects of sampling from bulk materials: Part 1: General principles Part 2: Sampling of particulate materials It is the intention of ISO/TC 69/SC 3 to develop additional parts under this general title for the sampling of liquids and gases, if the need exists. ISO 11648
24、-1:2003(E) ISO 2003 All rights reserved vIntroduction This first part of ISO 11648 gives a broad outline of the statistical aspects of sampling from bulk material. International Standards dealing with the methods for sampling for bulk materials, such as solid fuels, iron ores, etc., have already bee
25、n published and some of these are being revised by the responsible technical committees. This International Standard provides a source of information for technical terms and sampling techniques for types of bulk materials for which International Standards on sampling have not yet been written. This
26、International Standard may also act as a bridge for mutual understanding of terms and methods between Technical Committees. INTERNATIONAL STANDARD ISO 11648-1:2003(E) ISO 2003 All rights reserved 1Statistical aspects of sampling from bulk materials Part 1: General principles 1 Scope This part of ISO
27、 11648 establishes the general principles for the application and statistical treatment of the sampling of bulk materials. It also provides general guidance and examples for estimating necessary variances and checking precision and bias when the average value of a quality characteristic is investiga
28、ted. Furthermore, this part of ISO 11648 gives information relating to the statistical analyses of serial data, by the use of variograms and correlograms. This part of ISO 11648 also defines the basic terms with definitions for the sampling of bulk materials. These terms are necessary for providing
29、a better understanding of sampling techniques as well as making it easier to fulfil requirements. NOTE Part 2 of ISO 11648 is applicable to particulate materials in bulk. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated refer
30、ences, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 565, Test sieves Metal wire cloth, perforated metal plate and electroformed sheet Nominal sizes of openings ISO 3534 (all parts), Statistics Vocabulary
31、 and symbols ISO 5725 (all parts), Accuracy (trueness and precision) of measurement methods and results 3 Terms, definitions, symbols and abbreviated terms 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 3534 and the following apply. NOTE 1 The tex
32、t bulk material shown after terms means the definition given is confined to the field of bulk sampling. NOTE 2 For further information on definitions, see Annex A. 3.1.1 bulk material amount of material within which component parts are not initially distinguishable on the macroscopic level ISO 11648
33、-1:2003(E) 2 ISO 2003 All rights reserved3.1.2 sample bulk material subset of a specified population made up of one or more sampling units 3.1.3 sampling act of drawing or constituting a sample 3.1.4 simple random sampling sampling where a sample of n sampling units is taken from a population in suc
34、h a way that all combinations of n sampling units have the same probability of being taken NOTE In bulk material sampling, if the sampling unit is an increment, the positioning, delimitation and extraction of increments should ensure that all sampling units have an equal probability of being selecte
35、d. 3.1.5 stratum mutually exclusive and exhaustive sub-population considered to be more homogeneous with respect to the characteristics investigated than the total population EXAMPLES In bulk material, strata, based on time, mass and space, are typically production periods (e.g. 15 min); production
36、masses (e.g. 100 t); holds in vessels, wagons in a train or containers. 3.1.6 stratified sampling sampling such that portions of the sample are drawn from the different strata and each stratum is sampled with at least one sampling unit NOTE In some cases, the portions are specified proportions deter
37、mined in advance. However, in post-stratified sampling, the specified proportions would not be known in advance. 3.1.7 stratified simple random sampling simple random sampling from each stratum 3.1.8 systematic sampling sampling according to a methodical plan NOTE 1 In bulk sampling, systematic samp
38、ling can be achieved by taking items at fixed distances or after time intervals of fixed length. Intervals can, for example, be based on mass or time. In the case of mass, sampling units or increments should be of equal mass. With respect to time, sampling units or increments should be taken from a
39、moving stream or conveyor, for example at uniform time intervals. In this case, the mass of each sampling unit or increment should be proportional to the mass flow rate at the instant of taking the entity or increment. NOTE 2 If the lot is divided into strata, stratified systematic sampling can be c
40、arried out by taking increments at the same relative locations within each stratum. 3.1.9 sampling unit bulk material one of the member parts, each with equal probability of selection in sampling, into which a population, comprised of the total quantity of bulk material under consideration, is divid
41、ed NOTE 1 In bulk sampling, the sampling units are characterized by having an equal probability of being selected. Once chosen, the entire sampling unit becomes a part of the whole sample. NOTE 2 When sampling from a bulk material is performed by removing individual increments, the sampling unit is
42、the primary increment. ISO 11648-1:2003(E) ISO 2003 All rights reserved 33.1.10 precision closeness of agreement between independent test results obtained under stipulated conditions NOTE 1 Precision depends only on the distribution of random errors and does not relate to the true value or the speci
43、fied value. NOTE 2 The measure of precision is usually expressed in terms of imprecision and computed as a standard deviation of test results. Less precision is reflected by a larger standard deviation. NOTE 3 Quantitative measures of precision depend critically on the stipulated conditions. Repeata
44、bility and reproducibility conditions are particulate sets of extreme stipulated conditions. 3.1.11 bias difference between the expectation of a test result and an accepted reference value NOTE 1 Bias is the total systematic error as contrasted to random error. There may be one or more systematic er
45、ror components contributing to the bias. A larger systematic difference from the accepted reference value is reflected by a larger bias value. NOTE 2 The bias of a measurement instrument is normally estimated by averaging the error of indication over an appropriate number of repeated measurements. T
46、he error of indication is the “indication of a measuring instrument less the true value of the corresponding input quantity”. 3.1.12 lot bulk material definite part of a population, comprised of the total quantity of bulk material under consideration, and where this part is considered as a quantity
47、of material for which specific characteristics are to be determined NOTE Commerce in bulk material often encompasses transactions involving single lots, and, in these cases, the lot becomes the population. 3.1.13 sub-lot bulk material definite part of a lot of bulk material 3.1.14 increment bulk mat
48、erial quantity of bulk material taken in one action by a sampling device NOTE 1 The positioning, delimitation and extraction of the increment should ensure that all parts of the bulk material in the lot have an equal probability of being selected. NOTE 2 Sampling is often carried out in progressive
49、mechanical stages, in which case it is necessary to distinguish between a primary increment which is extracted from the lot at the first sampling stage, and a secondary increment which is extracted from the primary increment at the secondary sampling stage, and so on. 3.1.15 composite sample bulk material aggregation of two or more increments taken from a lot 3.1.16 gross sample bulk material aggregation of all the increments taken from a sub-lot or lot by the procedures of routine sampling ISO 11648-1:2003(E) 4 ISO
