[Freegis-list] Cooperative mapping project proposal
Tue, 27 Mar 2001 08:35:59 +1000
Hi Felipe and everyone,
> I strongly support your initiative. Leaving the initiative
>to the user, such a system has chances to be as successfully as
>another initiatives that share the same principle (think about
>the Free Software/Open Source movement).
I'm glad to hear such enthusiasm for the project. Thanks for
your thoughts on how it should be done.
>To build a such infrastructure that enable and incentive the
>participation of a user community, I think there are 3 main
>issues to be addressed: (1) data structure, (2) metadata, and
>(3) user interaction.
>How you will receive, store and send the data: you have choosed
>to use the shape file format, which is a good choice, since it
>is well documented and there is a very good Free library available
>to deal with it, as you stated before. But you could also use a
>traditional RDBMS to store it, in a OpenGIS Simple Feature
>specification fashion, and send and receive data in GML2, for
>example. And also receive classical GPS tracklogs in NMEA format.
>Just another possibilities.
I have spent quite a long time trying to work out how this should be
done and I'm still looking at options. You mentioned the GML2 format
for GIS data. I would like to use this in order to comply with OpenGIS
standards but I'm not aware of any free web-GIS that can support it,
or any conversion tool that can read/write it.
The format of GPS track logs is also something I've been meaning to
learn more about. Do you know if NMEA is a format used by the majority
of GPS receivers? If not, are there many GPS log formats that make up the
majority of the market share?
>I think the main problems that you will have to deal with are about
>metadata. Digital Geospatial Metadata is on the top of my interest
>subject list. Currently I am reading some standard specifications
>(from US FGDC, ISO, Auzlig and Dublin Core), but the long-term
>objective is to build a generic Free MDBMS - Metadata-base Managment
>System (unfortunetely, it advances as time allows). Maybe we can
>share some ideas and work, making the project of each one better
>and avoiding duplicated effort. Just a thought.
Sharing some ideas and work on this subject would be good. I'll have to
do a lot of reading on the subject before I'm up to speed with it though.
A free MDBS sounds like a great idea.
>And about the 3rd issue, I think a set of guidelines would be enough
>to drive the users efforts. And, when in doubt (about category
>classification, and data assurence, for example), I would leave the
>decision to the user. Maybe a rating mechanism of bases by users
>would be a good reasonable solution.
I think you might be right here. I guess what I'll be doing initially is
trying to find out what does work and improving the process over time.
>I also recommend you to take a look in some papers about ontologies in
>semantic interoperability for GISs. Frederico Fonseca, from University
>of Maine (www.spatial.maine.edu/~fred) has some papers about it.
Thanks. I'll have a good look at some of those papers.
Thanks again for your advice and support.