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RE: Where are the semantics in the semantic Web?

From: Shi, Xuan <xshi@GEO.WVU.edu>
Date: Fri, 25 Nov 2005 13:19:54 -0500
Message-ID: <D81F456794C18B4DA3E2ABC47DBBEEF2094E4E@onyx.geo.wvu.edu>
To: "'Harry Halpin '" <hhalpin@ibiblio.org>, "'public-sws-ig@w3.org '" <public-sws-ig@w3.org>

...

So - XML and XML Schema are primarily for data exchange when two or more
parties have an agreed upon exchange format, but often in Web Service
discovery and data integration this is not the case [2]. 


--In GIS domain, this is required in Web service discovery and data/service
integration. Since spatial data can be genereated in different spatial
reference systems (SRS) (UTM, SP North/South, etc. ) using different datums
(NAD83, NAD27, etc.), it is required that spatial data be overlaid with the
same SRS/datum. Details about SRS/datum specifications can be found at:
http://edndoc.esri.com/arcims/9.1/ , under the "Contents" tab, click
"Coordinate IDs and Descriptions".

For this reason, if requesters want to find Web services to process the data
or integrate the data into the map Web service, they should know service
provider's SRS/datum information in advance to make sure such integration or
data processing will get the right result. As for service providers, they
should check such information before they process the request otherwise they
just waste their resource. As for integrated mapping service, the service
requester and provider also need to make sure the bounding box of input
dataset matches the map extent of the mapping service. This means if I
provide a mapping service for West Virginia, it is useless for requesters
who want to add the dataset of other states. This should be done in the
process of service discovery and integration.

There is a big
difference between data exchange (serializing your data in vanilla
XML/XML Schema) and doing data integration and data discovery. The
question of the hour is - can the SemWeb solve the data
integration/discovery problem, the central issue of the Web?



--Yes, we can do this in GIS domain. Please visit this testing Web site:

http://157.182.136.76/esriuc/mapviewer/Webform1.aspx (you need a SVG plugin
to view the maps. SVG viewer is free downlaodable from Adobe)

All functions for integrating client-side dataset into server-side base map
are supported by Web services listed in:
http://157.182.136.76/esriuc/svgmapgenerator/Service1.asmx

The critical problem here again is how can we describe the data and servcie
semantics for discovery, matchmaking, composition and integration.
Obviously, metadata and meta-service information should be released in
service description document as requesters want to know if they find the
correct service to match their needs.
Received on Friday, 25 November 2005 18:19:25 GMT

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