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Copyright © 2013 Open Geospatial Consortium
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6.3 Description
There are many commercially-available geospatial tools that exploit OGC standards. Using NIEM messages, this experiment demonstrated that GML content can be embedded in NIEM conformant XML and be exploited
by commercial and open source tools without loss of precision e.g., right number of bits or accuracy e.g., physical location on a map. Embedding GML in NIEM conformant XML was accomplished in MOGIE using
the NIEM adapter.
There were two facets to MOGIE. The primary facet involved demonstrating the NIEM v2.1v3.0 technical concepts work in combination with OGC’s geospatial standards e.g., GML, WFS, WMS, etc. in the following
contexts:
NIEM conformant information exchange packages IEPs may contain embedded GML elements, in accordance with the GML Encoding Specification and the embedding GML best practice paper in
Appendix K. This was demonstrated by embedding GML content in four different NIEM Information Exchange Package Documentations IEPDs and resultant IEPs. The IEPDs used in this experiment
included:
Vessel Position Report developed by the NIEM Maritime Domain Awareness domain. MOGIE Position Report loosely based on the DoD Message Text Format USMTF standard
and Variable Message Format VMF. MOGIE Observation Report loosely based on the DoD Message Text Format USMTF
standard and Variable Message Format VMF. MOGIE Call for Fire loosely based on the DoD Message Text Format USMTF standard and
Variable Message Format VMF. The content in NIEM conformant IEPs, including embedded GML content, may be extracted and
transformed into an OGC-standard format e.g. GML, KML, and then displayed on a client through a WFS-conforming interface. Instance data was parsed and inserted into a PostGIS database. The data
was then provided through a WFS-conforming interface by GeoServer and displayed on a variety of commercial and open source products including desktop client applications, browser based applications,
and handheld devices.
The content from MilOps IEPs may be transformed to OGC-standard formats andor made available through a WFS-conforming interface without loss of accuracy or precision. Data in the experiment was
captured in raw form prior to transmission, and compared with the data stored in the PostGIS database after transmission, and compared with the data served up by GeoServer in WFS.
The secondary facets of MOGIE were included at the request of the DoD stakeholder community and are of equal importance. They included:
Evaluate whether use of NIEM required specialty skills. That is to say, evaluate how difficult was it for someone who had never used NIEM before to understand and utilize a NIEM IEPD. The software
developer selected for MOGIE had no experience with NIEM, and had 5 years of experience developing with commodity skills such as Java, general programming, XML, databases, etc.
Evaluate and identify other potential limitations in the architecture outside the scope of the XML data exchange that could potentially affect data accuracy and precision in the experiment.
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Copyright © 2013 Open Geospatial Consortium
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Use and evaluate the “GML Validator” tool currently being developed in OWS-9 as appropriate to determine compliance of GML in a MilOps exchange to GML Encoding Specifications, WFS, WMS,
etc. Reference: http:cite.opengeospatial.orgte2
. This evaluation is provided in Appendix C. Demonstrate that, if the NIEM content is modified to be GML application schema compliant delivered
via OGC compliant services it can be exploited by a broad range of OGC clients which have no a-priori knowledge of the source..
Evaluate the commercial implementation and support for the latest draft of the Military Standard 2525D.
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6.4 Use cases