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Product Lifecycle Metadata Harmonization with the Future in OAIS Archives

Metadata plays a crucial role in supporting the discovery, understanding and management of the large product data collections generated throughout all phases of the product lifecycle. Product data models are annotated with metadata which represent meaning in conformance with evolving metadata schemas while, for business, contractual and legal reasons, these semantically enriched models are ingested into OAIS (Open Archival Information System) based archives for later reuse. Notably, it is not uncommon for a product service provider to operate products for several decades; even after the engineers whose embodied knowledge supports their operation retire or leave the company. This product longevity and volatile knowledge, alongside rapid technological innovations and evolving metadata schemas, require that special preservation processes be used to keep the archived product data and metadata interpretable. While preservation of the data is concerned with product data model normalization, validation and file format migration, the preservation processes for metadata are of a different nature given that referenced schemas evolve independently from the products they describe. Although widely referenced, the OAIS reference model unfortunately does not observe metadata schema versioning or metadata harmonization in any depth. This paper therefore aims to introduce dedicated metadata preservation functionality into OAIS archives, based on operational schema update processing.