ISO/PAS 19450:2015

PUBLICLY ISO/PAS
AVAILABLE 19450
SPECIFICATION
First edition
2015-12-15
Automation systems and integration —
Object-Process Methodology
Systèmes d’automatisation et intégration — Object-Process
Methodology
Reference number
ISO/PAS 19450:2015(E)
©
ISO 2015

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ISO/PAS 19450:2015(E)

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ISO/PAS 19450:2015(E)

Contents Page
Foreword .vi
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 8
5 Conformance .10
6 OPM principles and concepts .10
6.1 OPM modelling principles .10
6.1.1 Modelling as a purpose-serving activity.10
6.1.2 Unification of function, structure, and behaviour .11
6.1.3 Identifying functional value .11
6.1.4 Function versus behaviour.11
6.1.5 System boundary setting .12
6.1.6 Clarity and completeness trade-off .12
6.2 OPM Fundamental concepts .12
6.2.1 Bimodal representation .12
6.2.2 OPM modelling elements .12
6.2.3 OPM things: objects and processes .13
6.2.4 OPM links: procedural and structural .13
6.2.5 OPM context management .14
6.2.6 OPM model implementation .14
7 OPM thing syntax and semantics .15
7.1 Objects .15
7.1.1 Description . . .15
7.1.2 Representation .15
7.2 Processes .15
7.2.1 Description . . .15
7.2.2 Representation .16
7.3 OPM things .16
7.3.1 OPM thing defined .16
7.3.2 Object-process test .16
7.3.3 OPM thing generic properties .17
7.3.4 Default values of thing generic properties .18
7.3.5 Object states .18
8 OPM link syntax and semantics overview .20
8.1 Procedural link overview .20
8.1.1 Kinds of procedural links .20
8.1.2 Procedural link uniqueness OPM principle .20
8.1.3 State-specified procedural links .20
8.2 Operational semantics and flow of execution control .20
8.2.1 The Event-Condition-Action control mechanism .20
8.2.2 Preprocess object set and postprocess object set .21
8.2.3 Skip semantics of condition versus wait semantics of non-condition links .21
9 Procedural links .22
9.1 Transforming links .22
9.1.1 Kinds of transforming links .22
9.1.2 Consumption link .22
9.1.3 Result link .23
9.1.4 Effect link .23
9.1.5 Basic transforming links summary .23
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ISO/PAS 19450:2015(E)

9.2 Enabling links .24
9.2.1 Kinds of enabling links .24
9.2.2 Agent and Agent Link . .24
9.2.3 Instrument and Instrument Link .25
9.2.4 Basic enabling links summary.26
9.3 State-specified transforming links .26
9.3.1 State-specified consumption link .26
9.3.2 State-specified result link .27
9.3.3 State-specified effect links .28
9.3.4 State-specified transforming links summary .30
9.4 State-specified enabling links .31
9.4.1 State-specified agent link .31
9.4.2 State-specified instrument link .32
9.4.3 State-specified enabling links summary .32
9.5 Control links .33
9.5.1 Kinds of control links .33
9.5.2 Event links .34
9.5.3 Condition links .40
9.5.4 Exception links .47
10 Structural links .48
10.1 Kinds of structural links .48
10.2 Tagged structural link .48
10.2.1 Unidirectional tagged structural link .48
10.2.2 Unidirectional null-tagged structural link .49
10.2.3 Bidirectional tagged structural link .49
10.2.4 Reciprocal tagged structural link.49
10.3 Fundamental structural relations .50
10.3.1 Kinds of fundamental structural relations .50
10.3.2 Aggregation-participation relation link .51
10.3.3 Exhibition-characterization link .52
10.3.4 Generalization-specialization and inheritance .55
10.3.5 Classification-instantiation link .58
10.3.6 Fundamental structural relation link and tagged structural link summary.61
10.4 State-specified structural relations and links .62
10.4.1 State-specified characterization relation link .62
10.4.2 State-specified tagged structural relations .63
11 Relationship cardinalities .67
11.1 Object multiplicity in structural and procedural links .67
11.2 Object multiplicity expressions and constraints.69
11.3 Attribute value and multiplicity constraints .71
12 Logical operators: AND, XOR, and OR .71
12.1 Logical AND procedural links .71
12.2 Logical XOR and OR procedural links .73
12.3 Diverging and converging XOR and OR links .74
12.4 State-specified XOR and OR link fans .76
12.5 Control-modified link fans .77
12.6 State-specified control-modified link fans .77
12.7 Link probabilities and probabilistic link fans .79
13 Execution path and path labels .81
14 Context management with OPM .83
14.1 Completing the SD .83
14.2 Achieving model comprehension.83
14.2.1 OPM refinement-abstraction mechanisms .83
14.2.2 Control (operational) semantics within an in-zoomed process context .87
14.2.3 OPM fact consistency principle .98
14.2.4 Abstraction ambiguity resolution for procedural links .99
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Annex A (normative) OPL formal syntax in EBNF .102
Annex B (informative) Guidance for OPM .121
Annex C (informative) Modelling OPM using OPM .124
Annex D (informative) OPM dynamics and simulation .157
Bibliography .163
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ISO/PAS 19450:2015(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is 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 in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that 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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is Technical Committee ISO/TC 184, Automation systems
and integration, Subcommittee SC 5, Interoperability, integration, and architectures for enterprise systems
and automation applications.
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ISO/PAS 19450:2015(E)

Introduction
Object-Process Methodology (OPM) is a compact conceptual approach, language, and methodology for
modelling and knowledge representation of automation systems. The application of OPM ranges from
simple assemblies of elemental components to complex, multidisciplinary, dynamic systems. OPM is
suitable for implementation and support by tools using information and computer technology. This
Publicly Available Specification specifies both the language and methodology aspects of OPM in order
to establish a common basis for system architects, designers, and OPM-compliant tool developers to
model all kinds of systems.
OPM provides two semantically equivalent modalities of representation for the same model: graphical
and textual. A set of hierarchically structured, interrelated Object-Process Diagrams (OPDs) constitutes
the graphical model, and a set of automatically generated sentences in a subset of the English language
constitutes the textual model expressed in the Object-Process Language (OPL). In a graphical-visual
model, each OPD consists of OPM elements, depicted as graphic symbols, sometimes with label
annotation. The OPD syntax specifies the consistent and correct ways to manage the arrangement of
those graphically elements. Using OPL, OPM generates the corresponding textual model for each OPD in
a manner that retains the constraints of the graphical model. Since the syntax and semantics of OPL are
a subset of English natural language, domain experts easily understand the textual model.
OPM notation supports the conceptual modelling of systems with formal syntax and semantics.
This formality serves as the basis for model-based systems engineering in general, including
systems architecting, engineering, development, life cycle support, communication, and evolution.
Furthermore, the domain-independent nature of OPM opens system modelling to the entire scientific,
commercial and industrial community for developing, investigating and analysing manufacturing
and other industrial and business systems inside their specific application domains; thereby enabling
companies to merge and provide for interoperability of different skills and competencies into a
common intuitive yet formal framework.
OPM facilitates a common view of the system under construction, test, integration, and daily maintenance,
providing for working in a multidisciplinary environment. Moreover, using OPM, companies can improve
their overall, big-picture view of the system’s functionality, flexibility in assignment of personnel to
tasks, and managing exceptions and error recovery. System specification is extensible for any necessary
detail, encompassing the functional, structural and behavioural aspects of a system.
One particular application of OPM is in the drafting and authoring of technical standards. OPM helps
sketch the implementation of a standard and identify weaknesses in the standard to reduce, thereby
significantly improving the quality of successive drafts. With OPM, even as the model-based text of a
system expands to include more details, the underlying model keeps maintaining its high degree of
formality and consistency.
This Publicly Available Specification provides a baseline for system architects and designers, who
can use it to model systems concisely and effectively. OPM tool vendors can utilise the PAS as a formal
standard specification for creating software tools to enhance conceptual modelling.
This Publicly Available Specification provides a presentation of the normative text that follows the
Extended Backus-Naur Form (EBNF) specification of the language syntax. All elements are presented in
Clauses 6 to 13 with only minimal reference to methodological aspects, Clause 14 presents the context
management mechanisms related to in-zooming and unfolding.
This specification utilizes several conventions for the presentation of OPM. Specifically, Arial bold font
in text and Arial bold italic font in figure captions, table captions and headings distinguish label names
for OPM objects, processes, states, and link tags. OPL reserved words are in Arial regular font with
commas and periods in Arial bold font. Most figures contain both a graphic image, the OPD portion, and
a textual equivalent, the OPL portion. Because this is a language specification, the precise use of term
definitions is essential and several terms in common use have particular meaning when using OPM.
Clause B.6 explains other conventions for the use of OPM.
Annex A presents the formal syntax for OPL, in EBNF form.
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Annex B presents conventions and patterns commonly used in OPM applications.
Annex C presents aspects of OPM as OPM models.
Annex D summarizes the dynamic and simulation capabilities of OPM.
The International Organization for Standardization (ISO) draws attention to the fact that it is claimed
that compliance with this document may involve the use of a patent concerning OPM as a modelling
system given in Clauses 6 to 14.
ISO takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured the ISO that he/she is willing to negotiate licences either
free of charge or under reasonable and non-discriminatory terms and conditions with applicants
throughout the world. In this respect, the statement of the holder of this patent right is registered with
ISO. Information may be obtained from:
Prof. Dov Dori
Technion Israel Institute of Technology
Technion City
Haifa 32000, Israel
dori@ie.technion.ac.il
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those identified above. ISO shall not be held responsible for identifying any or
all such patent rights.
ISO (www.iso.org/patents) and IEC (http://patents.iec.ch) maintain on-line databases of patents
relevant to their standards. Users are encouraged to consult the databases for the most up to date
information concerning patents.
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PUBLICLY AVAILABLE SPECIFICATION ISO/PAS 19450:2015(E)
Automation systems and integration — Object-Process
Methodology
1 Scope
This Publicly Available Specification specifies Object-Process Methodology (OPM) with detail sufficient
for enabling practitioners to utilise the concepts, semantics, and syntax of Object-Process Methodology
as a modelling paradigm and language for producing conceptual models at various extents of detail,
and for enabling tool vendors to provide application modelling products to aid those practitioners.
While this Publicly Available Specification presents some examples for the use of Object-Process
Methodology to improve clarity, it does not attempt to provide a complete reference for all the possible
applications of Object-Pr
...