Template:— activity_dependency (act_dep)
Context:— UK_Defence

Date: 2009/04/17 09:51:34
Revision: 1.2

Cover Contents Description Bus. perspective Bus. obj.Model diags.Input params.Ref. params.Instantiation path Instance diags.Characterizations Issues in situ

This section specifies the template activity_dependency.

NOTE The template has been defined in the context of UK_Defence. Refer to the business context for details of related templates.

NOTE An explanation of a template and the associated instantiation path is provided in the Template overview section.

Description

This template describes how to represent the relationship between an activity and a predecessor activity that must be completed, before the activity can be started.

Business perspective

The activity_dependency business object is used by those UK_Defence Data Exchange Specifications that require information about the relationship between an actual activity and it's predecessor activity..

Business object definition

Figure 1 — Graphical Representation for Business Object Activity

Activity_dependency:

The definition of an activity_dependency object is: Data about the relationship between an activity and a predecessor activity that must be completed, before the activity can be started.

Attribute name	Attribute description	Attribute type	Optionality
Predecessor_activity	This is the reference to the activity which needs to be completed before the related activity can start.	Activity	Mandatory
Related_activity	This is the reference to the activity that is dependent on the predecessor activity having been completed before it can start.	Activity	Mandatory
ID	This is the Identifier of the activity_dependency. Currently the requirement for this is the subject of an issue.	Identifier	Mandatory

Table 1 — Activity_dependency attribute details

Model diagrams

The EXPRESS-G diagram in Figure 2 shows the templates and EXPRESS entities that are required to represent the template "activity_dependency". The text highlighted in blue shows the template parameters.

Figure 2 — An EXPRESS-G representation of the Information model for activity_dependency

The graphic for the template to be used in other EXPRESS-G diagrams is shown in Figure 3 below.

Figure 3 — The graphical representation of the activity_dependency template

Input parameters

The following input parameters are defined for this template:

predecessor_activity (Type= 'ENTITY (Activity)' )

This is the reference to the activity which needs to be completed before the related activity can start.

related_activity (Type= 'ENTITY (Activity)' )

This is the reference to the activity that is dependent on the predecessor activity having been completed before it can start.

Reference parameters

The following reference parameters are defined for this template:

act_rel(Type='ENTITY (Activity_relationship)')

Allow the Activity_relationship entity instantiated in this path to be referenced when this template is used.

Note: The Activity_relationship entity can be referenced in a template path by:

%^target = $activity_dependency.act_rel%

where target is the parameter to which the Activity_relationship is bound.

Uniqueness constraints

The following parameter combinations specify a uniqueness constraint:

Unique constraint: Unique activity_dependency

Each instance of the entity (Activity_relationship) within the data set shall be uniquely identified by a combination of the following parameters on this template (activity_dependency) namely: predecessor_activity, related_activity.
The instance is referenced by the following template parameter: act_rel.

There should be one predecessor and related activity within the relationship.

Instantiation path

The instantiation path shown below specifies the entities that are to be instantiated by the template.

A description of templates and the syntax for the instantiation path is provided in the Templates Help/Information section.

-- instantiate Activity_relationship
Activity_relationship
%^act_rel = Activity_relationship%
^act_rel.name = '/IGNORE'
^act_rel.description = '/IGNORE'
^act_rel.relating_activity -> @predecessor_activity
^act_rel.related_activity -> @related_activity

The following entities are instantiated with attributes as specified:

Entity in path	Value	Inherited from
Activity_relationship.name	'/IGNORE'	—
Activity_relationship.description	'/IGNORE'	—

Instance diagrams

The instance diagram in Figure 4 shows an example of the EXPRESS entities and templates that are instantiated by the template:

/activity_dependency(related_activity='@91', predecessor_activity='@2')/

(an illustration of the consolidated activity_dependency template is shown in Figure 5 below.)

Figure 4 — Entities instantiated by activity_dependency template

The instance diagram in Figure 5 shows the graphic symbol for the template that is to be used in other instance diagrams. The example template is:

/activity_dependency(related_activity='@91', predecessor_activity='@2')/

Figure 5 — Instantiation of activity_dependency template

Characterizations

No common characterizations of the template activity_dependency have been identified. However, the ISO 10303-239 EXPRESS model may enable other assignments to the entities instantiated by the template.