56 3 Non-geometry standards
Background
A conceptual schema language is based upon a conceptual formalism that provides the rules, constraints, inheritance mechanisms, events, functions, processes and
other elements that make up a conceptual schema language. For the ISO 19100 family of standards the applicable conceptual formalism is the object-oriented modelling
as described by OMG (OMG 2003). A conceptual schema language has to be capable of representing 100% of the semantics in a domain of discourse (see section
2.2.3). The 100%-requirement refers to the level of detail that is appropriate for
modelling the domain in question. Traditional conceptual schemata such as the Entity-Relation model cannot describe numericalor logical relationships between values of concept. Therefore they are not able to meet the 100% requirement.
The UML has become the strongest of several conceptual schema languages that
have been developed over the last decade. The roots of UML were independent but
similar to developments by three well-known American "software methodologists":
Booch, Rumbaugh, and Jacobson. These three later pooled their efforts and created a
company, Rational Software Corporation, that has become the leading developer of
software engineering tools. UML is about to become an International Standard prepared by the ISO/IEC JTCl/SC7 (ISOIEC47 2003). Today Rational Software Corporation is a division of IBM.
EXPRESS is a conceptual schema language being used in the field of mechanical
engineering and was standardised by the ISO/TC 184 (Industrial automation systems
and integration) (lSOIEC25 1994). Conceptual schemas in UML are based on
graphical and lexical elements, whereas the schemas of EXPRESS primarily rely on
text. According to the standards of the ISO 19100 series, both languages are available for the modelling of geographic information. UML is preferred however, as it
has turned out to be far more feasible for modelling geomatics. Therefore, this book
uses UML as the only conceptual schema language.
UML elements for geographie information
The ISO/TS 19103 (Conceptual schema language) requires the use of UML as it
is defined in the ISO/IEC 19501-1. Specific rules and recommendations have been
established for the following aspects: classes, attributes, datatypes, operations, associations, and stereotypes. In addition, naming conventions and modelling guidelines
maintain the unique appearance ofthe whole family ofISO 19100 standards (see annex E).
Classes
Normative models use class-diagrams and package diagrams. Other UML diagram-types, such as use-case diagrams, may be used for information. All normative
models contain complete definitions of attributes, associations, operations, and appropriate data type definitions.
According to the ISO 19100 family, a class is viewed as a specification and not as
an implementation. Attributes are considered to be abstract, and do not have to be di-
Background
A conceptual schema language is based upon a conceptual formalism that provides the rules, constraints, inheritance mechanisms, events, functions, processes and
other elements that make up a conceptual schema language. For the ISO 19100 family of standards the applicable conceptual formalism is the object-oriented modelling
as described by OMG (OMG 2003). A conceptual schema language has to be capable of representing 100% of the semantics in a domain of discourse (see section
2.2.3). The 100%-requirement refers to the level of detail that is appropriate for
modelling the domain in question. Traditional conceptual schemata such as the Entity-Relation model cannot describe numericalor logical relationships between values of concept. Therefore they are not able to meet the 100% requirement.
The UML has become the strongest of several conceptual schema languages that
have been developed over the last decade. The roots of UML were independent but
similar to developments by three well-known American "software methodologists":
Booch, Rumbaugh, and Jacobson. These three later pooled their efforts and created a
company, Rational Software Corporation, that has become the leading developer of
software engineering tools. UML is about to become an International Standard prepared by the ISO/IEC JTCl/SC7 (ISOIEC47 2003). Today Rational Software Corporation is a division of IBM.
EXPRESS is a conceptual schema language being used in the field of mechanical
engineering and was standardised by the ISO/TC 184 (Industrial automation systems
and integration) (lSOIEC25 1994). Conceptual schemas in UML are based on
graphical and lexical elements, whereas the schemas of EXPRESS primarily rely on
text. According to the standards of the ISO 19100 series, both languages are available for the modelling of geographic information. UML is preferred however, as it
has turned out to be far more feasible for modelling geomatics. Therefore, this book
uses UML as the only conceptual schema language.
UML elements for geographie information
The ISO/TS 19103 (Conceptual schema language) requires the use of UML as it
is defined in the ISO/IEC 19501-1. Specific rules and recommendations have been
established for the following aspects: classes, attributes, datatypes, operations, associations, and stereotypes. In addition, naming conventions and modelling guidelines
maintain the unique appearance ofthe whole family ofISO 19100 standards (see annex E).
Classes
Normative models use class-diagrams and package diagrams. Other UML diagram-types, such as use-case diagrams, may be used for information. All normative
models contain complete definitions of attributes, associations, operations, and appropriate data type definitions.
According to the ISO 19100 family, a class is viewed as a specification and not as
an implementation. Attributes are considered to be abstract, and do not have to be di-