X3ML Framework: An Effective Suite for Supporting Data Mappings.

The aggregation of heterogeneous data from different institutions in cultural heritage and e-science has the potential to create rich data resources useful for a range of different purposes, from research to education and public interests. In this paper, we present the architecture and functionality of X3ML data exchange framework, that handles effectively and efficiently the schema mapping, URI definition and generation, and data transformation steps of the provision and aggregation process. The X3ML framework is based on the X3ML mapping definition language that offers the building blocks for describing both schema mappings and URI generation policies, and the X3ML engine, that handles the URI generation and the data transformation. The X3ML framework supports the cognitive process of mapping and it has a lot of advantages compared to other existing tools including that the schema mappings are expressed in a declarative way, and are both human and machine readable allowing domain experts to understand them, the schema matching and the URI generation policies comprise different distinct steps in the exchange workflow, and follow different life cycles. Furthermore X3ML is symmetric and potentially invertible allowing bidirectional interaction between providers and aggregator and thus supporting not only a rich aggregators’ repository but also corrections and improvements in the providers’ data bases.