1132 codes for typical_activities

It is often necessary to classify typical activities with code values (as well as plain english names). For example a drillstem test activity may be one of the following: drillstem test for cased hole, drillstem test for open hole, extended well test or injectivity test. These typical activities have an associated codes: DSTC, DSTO, EWT, INJ. At the moment, the model does not allow typical_activity to have a ref_code_alias to describe these codes. Associated ref_code_alias to reference entities is only valid for the subtypes of ref_code. We suggest that this mechanism should also be available for subtypes of reference_behavior (typical_activity, coordinate_system, etc..). The implication on the model would be to add an attribute in the ref_code_alias entity that points to the reference_behavior entity.

add class alias entities

Add class alias entities with relationships to classification system and the specific class entities. Also add ref_classification_system to qualify classification_system, to distinguish between naming system (classification system) and what kind of thing it is.

Added objects:
activity_class_alias (Entity)
equipment_class_alias (Entity)
facility_class_alias (Entity)
material_class_alias (Entity)
activity_class.activity_class_alias (Attribute)
equipment_class.equipment_class_alias (Attribute)
facility_class.facility_class_alias (Attribute)
material_class.material_class_alias (Attribute)
classification_system.activity_class_alias (Attribute)
classification_system.equipment_class_alias (Attribute)
classification_system.facility_class_alias (Attribute)
classification_system.material_class_alias (Attribute)
HL6:_Class_Aliasing (Diagram)
ref_classification_system (Entity)
classification_system.kind (Attribute)