Susan Redline et al.,
Described the next version of this Sleep-Repository/Analytic Warehouse called Hybrid. Described a Ruby on Rails implementation.
Reconciliation of data types across multiple ontologies is done by local mapping of member data sources into a data dictionary. The decision was explicitly made to allow transparency into these source data at the cost of having the investigator determine the validity of the mappings and their semantics for each of the data sources.