ASD-STAN PREN 9300-003-2009 Aerospace series LOTAR LOng Term Archiving and Retrieval of digital technical product documentation such as 3D CAD and PDM data Part 003 Fundamentals an.pdf

1、ASD STANDARD NORME ASD ASD NORM prEN 9300-003 Edition P 1 October 2009 PUBLISHED BY THE AEROSPACE AND DEFENCE INDUSTRIES ASSOCIATION OF EUROPE - STANDARDIZATIONAvenue de Tervuren, 270 - B-1150 Brussels - Tel. + 32 2 775 8126 - Fax. + 32 2 775 8131 - www.asd-stan.orgICS: Descriptors: ENGLISH VERSION

2、Aerospace series LOTAR LOng Term Archiving and Retrieval of digital technical product documentation such as 3D, CAD and PDM data Part 003: Fundamentals and concepts Srie arospatiale LOTAR Archivage Long Terme et rcupration des donnes techniques produits numriques, telles que CAD 3D et PDM Partie 003

3、 : Fondamentaux et concepts Luft- und Raumfahrt LOTAR Langzeitarchivierung und Bereitstellung digitaler technischer Produktdokumentationen, beispielsweise 3D CAD und PDM Daten Teil 003: Grundlagen und Konzepte This “Aerospace Series“ Prestandard has been drawn up under the responsibility of ASD-STAN

4、 (The AeroSpace and Defence Industries Association of Europe - Standardization). It is published for the needs of the European Aerospace Industry. It has been technically approved by the experts of the concerned Domain following member comments. Subsequent to the publication of this Prestandard, the

5、 technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and review by users and formal agreement of ASD-STAN, it will be submitted as a draft European Standard (prEN) to CEN (Eu

6、ropean Committee for Standardization) for formal vote and transformation to full European Standard (EN). The CEN national members have then to implement the EN at national level by giving the EN the status of a national standard and by withdrawing any national standards conflicting with the EN. Edit

7、ion approved for publication 31 October 2009 Comments should be sent within six months after the date of publication to ASD-STAN Engineering Procedures and Processes Domain Copyright 2009 by ASD-STAN prEN 9300-003:2009 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms, definit

8、ions and abbreviations5 4 Major differences of terms5 5 Applicability. 12 6 Overview of referenced standards 12 7 Fundamentals and concepts . 17 8 Description methods 30 Figures Figure 1 Example for retrieve use case for specification of long term retention. 9 Figure 2 Retention and Long Term Archiv

9、ing . 10 Figure 3 Scope of EN 9300. 11 Figure 4 OAIS Environment 13 Figure 5 Functional Model of OAIS. 14 Figure 6 Overview about Structure of ISO 10303. 15 Figure 7 Application example, formal schema definition and mapping onto Part 21 file format. 15 Figure 8 Distinction of Business requirements,

10、Business Cases and Use Cases 17 Figure 9 Scope definition for EN 9300 (grey marked rectangle). 18 Figure 10 Concept of a core model. 21 Figure 11 Concept of validation/verification 25 Figure 12 Overview of data conversion and data definitions 26 Figure 13 Explicit process example 27 Figure 14 Specia

11、l use cases . 28 Figure 15 Mapping approach onto physical data representation28 Figure 16 Data validation by comparison of defined validation properties . 29 prEN 9300-003:2009 (E) 3 Foreword This standard was prepared jointly by ASD-STAN and the PROSTEP iViP Association. The PROSTEP iViP Associatio

12、n is an international non-profit association in Europe. For establishing leadership in IT-based engineering it offers a moderated platform to its nearly 200 members from leading industries, system vendors and research institutions. Its product and process data standardization activities at European

13、and worldwide levels are well known and accepted. The PROSTEP iViP Association sees this standard and the related parts as a milestone of product data technology. Users should note that all standards undergo revision from time to time and that any reference made herein to any other standard implies

14、its latest edition, unless otherwise stated. prEN 9300-003:2009 (E) 4 1 Scope This document defines basic terms, e.g., Long Term Archiving and Retention and identifies the context and scope of EN 9300. The section Fundamentals describes the basic concepts and approaches of EN 9300 and referenced rel

15、ated standards. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 9103, A

16、erospace series Quality management systems Variation management of key characteristics. EN 9300-007*, Aerospace series LOTAR Long Term Archiving and Retrieval of digital technical product documentation such as 3D, CAD and PDM data Part 007: Terms and references. 1)ISO 10303-203:1994 and Edition 2 dr

17、aft, Industrial automation systems and integration Product data representation and exchange Part 203: Application protocol: Configuration controlled 3D designs of mechanical parts and assemblies. ISO 10303-209:2001, Industrial automation systems and integration Product data representation and exchan

18、ge Part 209: Application protocol: Composite and metallic structural analysis and related design. ISO 10303-210:2001, Industrial automation systems and integration Product data representation and exchange Part 210: Application protocol: Electronic assembly, interconnection, and packaging design. ISO

19、 10303-212:2001, Industrial automation systems and integration Product data representation and exchange Part 212: Application protocol: Electrotechnical design and installation. ISO 10303-214:2001 and ISO 10303-214:2003, Industrial automation systems and integration Product data representation and e

20、xchange Part 214: Application protocol: Core data for automotive mechanical design processes. ISO 10303-233, Industrial automation systems and integration Product data representation and exchange Part 233: Systems engineering data representation. 1)ISO 10303-237, Industrial automation systems and in

21、tegration Product data representation and exchange Part 237, Application protocol: Fluid dynamics 1)ISO 14721, Space data and information transfer systems Open archival information system Reference model. ARP9034, A Process Standard for the Storage, Retrieval and Use of Three-Dimensional Type Design

22、 Data. BP 0008, Code of Practice for Legal Admissibility and Evidential Weight of Information Stored electronically. *And all parts quoted in this standard. 1) In preparation at the date of publication of this standard. prEN 9300-003:2009 (E) 5 3 Terms, definitions and abbreviations For the purposes

23、 of this document, the terms, definitions and abbreviations given in EN 9300-007 apply. 4 Major differences of terms 4.1 Introduction 4.1.1 General Different user communities have different definitions for long term archiving and retention. This chapter explains the major differences of both terms a

24、nd their relation to the scope of EN 9300. Companies within the aerospace industry need to keep data to fulfil business, certification and legal requirements. For modern definitions this data is usually digital. These requirements lead to four main areas of consideration regarding the retention of d

25、igital data. Invariance: how important is it to ensure that digital data is not altered Objectives: why keeping of digital data is required Length of time: the required length of time for retaining digital data Stored Form: the stored format of the digital data The following subchapters consider the

26、se questions for long term archiving and retention and are the basis for the scope definition of EN 9300. The scope of EN 9300 is a combination of aspects from long term archiving and retention. 4.1.2 Invariance Invariance covers the need to ensure that the information has not changed and so provide

27、 evidential weight that the design intent has not changed, see Figure 13. Three categories can be distinguished: Auditable where validation methods and test suites ensure that information cannot be changed without the change being detected. Implicit where the system is designed to prevent changes. T

28、he system must supervise activities which would result in changes of the digital data. The supervision, for example, could be realized within a separate write-protected vault. The proof of “no change“ is shown by an absence of change having been recorded AND that by showing that the system itself is

29、 reliable. Not required where changes to data are not explicitly controlled. Of the three, auditable invariance is the strongest, and is likely to be the most suitable where the information is used in legal proceedings. 4.1.3 Objectives for keeping digital data For digital data, the challenge is tha

30、t the data are often stored in a proprietary, native format and will most likely become not interpretable after a time. The use of a neutral archiving data format safeguards the interpretability of the stored data for a much longer time, perhaps for the entire retention period. EN 9300 recommends th

31、e use of standard formats for long term archiving rather than native formats, accompanied by regular and frequent migrations of storage media and, if necessary, of data format. Because a data migration may lead to data loss, usually time stamps and digital signatures (which are used ensuring the int

32、egrity and immutability of archived data/ data packages) have to be renewed. The use of auditable archiving and retrieval processes ensures the data readability and integrity within current and future systems. prEN 9300-003:2009 (E) 6 The objectives for keeping the data are distinguished into two ma

33、jor subcategories: Legal requirements/certification requirements, such as for proof of technical documentation for actions in law. Business requirements, such as keeping knowledge. Within the two subcategories EN 9300-003 offers four characteristics which describe the objectives in more detail: To p

34、reserve the original data (generated by a source system) so that it can be used as evidence of what data was at a particular date. This characteristic fits with the subcategory legal requirement To keep data available to new users over the period for which it is kept. This characteristic fits with t

35、he subcategories legal requirement and business requirement. To be able to preserve the source of the kept data. This characteristic fits with the subcategory business requirement. To be able to reuse the data, for example, by modifying design data to meet new requirements. This characteristic fits

36、with the subcategory business requirement. 4.1.4 Length of time of keeping data The life cycle of software and hardware is relatively short compared to the life cycle of aircraft. The life cycle of digital data can be described in terms of software versions and generations. The release of a new soft

37、ware version within a generation general alters only a small part of the functionalities of the software without affecting the data format. A generation change occurs when the software used changes substantially, for example, to a new architecture. The change of a generation may result in new data f

38、ormats. Currently, for CAD software, the period between versions is of the order of 6 months to 12 months, while between generations is of the order of 3 years to10 years. This should be compared to an aircraft life cycle which may be 30 years to 50 years or longer. This gives rise to the following

39、definitions within EN 9300: Short term - within one or two versions Medium term - within one generation Long term - over multiple generations Additionally to the technical aspects, legal requirements have to be considered when defining archiving terms. For further information see EN 9300-001 (Struct

40、ure) and EN 9300-002 (Requirements). 4.1.5 Stored Form 4.1.5.1 General A key distinction is between a representation and a presentation. In a representation, the computer holds the information about the concept, whereas in a presentation the computer holds a form which is its appearance to a human.

41、For example, a musical score is a representation of a piece of music, whereas a recording of the piece is a presentation. The stored form has been divided into three main subcategories: Detail Level: the description level of model; Representation: describing the different logical forms of data repre

42、sentation; Format: describing the different physical formats of the data. prEN 9300-003:2009 (E) 7 4.1.5.2 Detail level An accurate representation is where data elements are described in the original level of detail, independent of whether they are represented in a native or other format; An approxi

43、mate representation is where data elements are described in a lower level of detail than the accurate representation, e.g., where a curved surface is approximated by a set of small, flat faces. 4.1.5.3 Representation A native representation is that created by and private to the source system; A deri

44、ved representation is a transformation of the native data, which may be based on a native format or on a standardized format, e.g., a html version may be derived from a text document as an alternative representation; A presentation is a visualization of data to a user, e.g. a drawing or a print out

45、of product structure information as a snapshot of the current data representation. 4.1.5.4 Format A native format is a specific format of data in a syntax which is proprietary and dependent on a specific system or interface. A native format depends directly on the life cycle (versions, generations)

46、of the related system or interface; A standardized open format is a format of data in a syntax, which is defined by a broad community, such as by ISO, and which is independent of specific system or interface. “Open” means completely and precisely documented in syntax and semantics and is applicable

47、for free. In addition, standardisation processes regulates the change processes for the standard. Note that the motivation for including the accurate and approximate representation is that both may be archived in parallel in a standard representation such as STEP, which is openly documented and whic

48、h may be stable for a much longer period than native formats. 4.2 Terminology 4.2.1 General From descriptions in 4.1, the following definitions of terms are derived: Product information model, Product model, Business Application, Retention and Long Term Archiving. These definitions are used within E

49、N 9300. 4.2.2 Product information model The Product information model represents an information model which provides an abstract description of facts, concepts and instructions about a product, e.g. STEP 2)Application reference model or STEP Application interpreted model. 2) ISO 10303-1:1994 prEN 9300-003:2009 (E) 8 4.2.3 Product model The Product model represents an occurrence of a product information model for a particular product, e.g. the ge