The following examples use the type model described below. All Propertyvalues are assumed to be string unless otherwise noted

New Reference types:

"HasChild" derived from HierarchicalReference.

"HasAnimal" derived from HierarchicalReference.

"HasPet" derived from HasAnimal.

"HasFarmAnimal" derived from HasAnimal.

"HasSchedule" derived from HierarchicalReference.

PersonType derived from BaseObjectType adds:

HasProperty "LastName".

HasProperty "FirstName".

HasProperty "StreetAddress".

HasProperty "City".

HasProperty "ZipCode".

May have HasChild reference to a node of type PersonType.

May have HasAnimal reference to a node of type AnimalType (or a subtype of this Referencetype).

AnimalType derived from BaseObjectType adds:

May have HasSchedule reference to a node of type FeedingScheduleType.

HasProperty "Name".

DogType derived from AnimalType adds:

HasProperty "NickName".

HasProperty "DogBreed".

HasProperty "License".

CatType derived from AnimalType adds:

HasProperty "NickName".

HasProperty "CatBreed".

PigType derived from AnimalType adds:

HasProperty "PigBreed".

ScheduleType derived from BaseObjectType adds:

HasProperty "Period".

FeedingScheduleType derived from ScheduleType adds:

HasProperty "Food".

HasProperty "Amount" (Stored as an Int32).

AreaType derived from BaseObjectTypeis just a simple Folderand contains no Properties.

This example type system is shown in Figure B.3. In this Figure, the OPC UA notation is used for all Referencesto ObjectTypes, Variables, Propertiesand subtypes.Additionally, supported Referencesare contained in an inner box. The actual references only exist in the instances, thus, no connections to other Objectsare shown in the Figure and they are subtypes of the listed Reference.

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Figure B.3– Example Type Nodes

A corresponding example set of instances is shown in Figure B.4. These instances include a type Referencefor Objects. Properties also have type References, but the Referencesare omitted for simplicity. The name of the Objectis provided in the box and a numeric instance NodeIdin brackets. Standard ReferenceTypesuse the OPC UA notation, custom ReferenceTypesare listed as a named Reference. For Properties, the BrowseName, NodeId, and Valueare shown. The Nodesthat are included in a View(View1) are enclosed in the coloured box. Two Area nodes are included for grouping of the existing person nodes. All custom nodes are defined in namespace 12 which is not included in Figure B.4.

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Figure B.4– Example Instance Nodes