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XML Cover Pages: UK Ordnance Survey’s Digital National Framework (DNF)

XML Cover Pages – Created: October 19, 2001

UK Ordnance Survey's Digital National Framework (DNF) Tests XML Schemas for Geographical Information.

Through its XML Schema Repository, the UK Digital National Framework
(DNF) has released a number of draft XML schemas supporting the
Ordnance Survey's geographical database. The schemas are based upon
extensions to the GML version 2.0 specification. The draft DNF Release
1 product data specification includes XML schema documents, a
specification overview, classification and attributes of DNF features,
DNF themes, lifecycles of DNF features, DNF geometry and topology, DNF
data in GML, and a DNF glossary. The DNF application schemas "define
four main types of properties that are present inside a feature
element. These are simple, complex, geometric, and topological
properties. The ordering of properties within a feature element is
important as XML validation is reliant on elements being in a specified
order; the order of properties is specified within the XML schema." The
Digital National Framework (DNF) "is a definitive, consistent and
maintained framework for the referencing of geographical information in
Great Britain. It comprises the [UK] National Grid linked to Global
Positioning System (GPS), height data, detailed topographic information
and unique identifiers on features. Key elements are: (1) Polygons: the
building blocks of the data representing real world features; (2)
Maintained topographic identifiers (TOIDs) on all features — some 400
million self-contained individual objects; (3) Seamless data; (4) A
themed classification based on the real world; (5) Availability of data
by themes; (6) Metadata on each feature…" 

Read the article on their website: The XML Cover Pages.

Download the PDF file: UK Ordnance Survey's Digital National Framework (DNF)