6. PRODUCT INSTANCE

6.1 Overview

The Product Instance Schema centers on the following:

∙Product Instance;

∙Product Instance Identification;

∙Product Instance Breakdown Structure;

∙Product Instance Usage History.

6.2Description

6.2.1 Product Instance

The data structures collected under the Entity product_instance_definition are dedicated to the management of the AS-BUILT/AS-USED view of the product.

A product_instance_definition is optionally related to exactly one product_concept and to exactly one product_design_definition. It may be associated with a person and/or organization with a specific role (e.g. owner, custodian, user, driver, pilot, etc. ) through the entity product_instance_organization_association. Additional information about the association is the date when the association was established and the date when it was ended. History of product instance ownership, for example, may be derived by screening the start_date and the end_date attributes. The current ownership is identified by the entity instance whose end_date attribute is empty. A product_instance may be associated with a location.

6.2.2 Product Instance Identification

The subtypes of the Entity product_instance_definition are related to the three different types of identification of a product instance. In particular, a product_instance may be identified by: (1) a serial number; (2) a lot number; or (3), for some types of material, just by a name. A globally unique identifier consisting of the organization code and the serial number/lot number must be used.

serial_

lot_numbered_ numbered_ material instance

instance

Figure 6.1 Identification of Product Instances

∙A serial number is an identifier consisting of alphanumeric characters which is assigned sequentially in the order of manufacture or final test which, in conjunction, with the manufacturer's identification (e.g id_owner), uniquely identifies a single item within a group of similar items manufactured from the same design.

∙A lot number is an identifier consisting of either a date or a string of alphanumeric characters which, in conjunction with the manufacturer's identification, uniquely identify a group of units of the same item which are manufactured or assembled by one producer under uniform conditions and which are expected to function in a uniform manner.

∙The term 'material' applies to bulk items that are liquid, powder, or some other form, such that a unit of measure, other than 'each', is necessary to describe any quantity of them. Materials should be identified by an appropriate name according to industry practices. Instances or material are identified by an internal unique identifier.

During the in-service phase, the user may need to issue additional identifiers to product instance (Tail, Plate numbers) in order to manage them within the user management system. In

PRODUCT_INSTANCE_SCHEMA EXPRESS-G diagram 1 of 4

date_installed date_removed

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6.4.8 product_instance_definition

A product definition that identifies physically realized products (e.g. identified by serial numbers).

ENTITY product_instance_definition

ABSTRACT SUPERTYPE OF (lot_numbered_instance ANDOR serial_numbered_instance ANDOR material);

6.4.9 product_instance_location_association

The association between a product instance and a location.

ENTITY product_instance_location_association;

6.4.10 product_instance_organization_association

The association between a product instance and person and/or organization with role.

ENTITY product_instance_organization_association;

6.4.11 product_instance_physical_decomposition

The association between two product_instance(s) where one is the parent and the other is the child.

ENTITY product_instance_physical_decomposition

SUBTYPE OF (product_instance_relationship);

6.4.12 product_instance_relationship

The association betwenn two product_instance(s). The meaning of the association is defined by the subtype entities.

ENTITY product_instance_relationship SUPERTYPE OF

(ONEOF(product_instance_physical_decomposition,alternate_product_

6.4.13 product_instance_substitution

An association between two product_instance_relationship where a parent-child relationship is replaced by a new parent-child relationship. The two product_instance_relationship that are associated by this entity shall have the same parent product_instance_definition (e.g. product_instance_relationship.relating).

ENTITY product_instance_substitution;

6.4.14 product_instance_usage_metrics_association

The association between a product_instance and a usage_metrics_parameter.

ENTITY product_instance_usage_metrics_association;

6.4.15 serial_numbered_instance

Product instances that are identified individually by a serial number.

ENTITY serial_numbered_instance

SUBTYPE OF (product_instance_definition);