[GeoNetwork-users] Examples of use of the aggregationInfo element?

GeoNetwork GeoNetwork User
1

Hi GN community,

I would be very interested to see real examples where people
have used the aggregationInfo element of ISO19115.

We are considering using the element to store hierarchical information
or to identify particular 'facilities' which gathered the data.

Any XML samples of metadata records or pointers to them
would be greatly appreciated.

Regards,

Andrew

2

Hi Andrew,

We've been working on this at British Antarctic Survey, trying to model our aerial photography data holdings. This is a hierarchy consisting of sorties which in turn consist of flightlines which in turn consist of a series of scene centres. I've found a lot of helpful information on NOAA's website e.g:

https://www.nosc.noaa.gov/dmc/swg/wiki/index.php?title=Metadata_Hierarchies

and

https://www.nosc.noaa.gov/dmc/swg/wiki/index.php?title=ISO_Aggregation

I think that aerial photography metadata would best be modelled using ISO19115-2, an enhancement to the basic standard specifically geared to imagery (the acquisitionInfo element is what's needed). However, despite help from the folks at NOAA, I haven't been able to add in the templates and schemas to GN 2.4.3 successfully. So I've resorted to a hybrid approach for our purposes. The attached example (zipped) shows a skeleton XML version of what I've come up with for aerial photography.

I have discovered that there are disadvantages to modelling the hierarchy like this, however. This is particularly true when using CSW to do spatial queries on the metadata. The whole hierarchy is a single record as far as Lucene is concerned, so when a spatial query such as flightline intersects bounding box is performed, GN will return the whole sortie. Not a great problem for aerial photography sorties which tend (for us) to be over a relatively small area.

The other way I have modelled hierarchies which doesn't suffer from this problem is to use the hierarchyLevel and parentIdentifier elements in gmd:MD_Metadata. This is very simple, if a bit painful to edit in the GN admin interface (you have to keep track of UUIDs). I have found this approach much better for automatically batch imported metadata rather than data entered manually.

Hope this helps,

David Herbert
British Antarctic Survey.

-----Original Message-----
From: andrew walsh [mailto:awalsh@anonymised.com]
Sent: 03 August 2010 04:17
To: geonetwork-users@lists.sourceforge.net
Cc: geonetwork-devel@lists.sourceforge.net
Subject: [GeoNetwork-users] Examples of use of the aggregationInfo element?

Hi GN community,

I would be very interested to see real examples where people
have used the aggregationInfo element of ISO19115.

We are considering using the element to store hierarchical information
or to identify particular 'facilities' which gathered the data.

Any XML samples of metadata records or pointers to them
would be greatly appreciated.

Regards,

Andrew
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(attachments)

17_Fid_P_11_4.zip (6.78 KB)

3

Hi David,

The information and the links you provided have been a big help
for our discussions. The NOAA links were particulary helpful.

It seems there are 3 ways to handle metadata heirarchies:

1) Parent Identifier/Hierarchy Level

2) Aggregation Info

3) DS_Aggregrate or DS_Series

So far we are leaning towards the Parent Identifier/Hierarchy Level approach
as it's nice and simple and fits in with some metadata we made up already for
one project. However the other 2 approaches could be useful in some cases.

Again, thanks for your information.

Regards,

Andrew

----- Original Message ----- From: "Herbert, David J" <darb1@anonymised.com>
To: "andrew walsh" <awalsh@anonymised.com>; <geonetwork-users@lists.sourceforge.net>
Sent: Tuesday, August 03, 2010 18:12
Subject: RE: [GeoNetwork-users] Examples of use of the aggregationInfo element?

Hi Andrew,

We've been working on this at British Antarctic Survey, trying to model our aerial photography data holdings. This is a hierarchy consisting of sorties which in turn consist of flightlines which in turn consist of a series of scene centres. I've found a lot of helpful information on NOAA's website e.g:

https://www.nosc.noaa.gov/dmc/swg/wiki/index.php?title=Metadata_Hierarchies

and

https://www.nosc.noaa.gov/dmc/swg/wiki/index.php?title=ISO_Aggregation

I think that aerial photography metadata would best be modelled using ISO19115-2, an enhancement to the basic standard specifically geared to imagery (the acquisitionInfo element is what's needed). However, despite help from the folks at NOAA, I haven't been able to add in the templates and schemas to GN 2.4.3 successfully. So I've resorted to a hybrid approach for our purposes. The attached example (zipped) shows a skeleton XML version of what I've come up with for aerial photography.

I have discovered that there are disadvantages to modelling the hierarchy like this, however. This is particularly true when using CSW to do spatial queries on the metadata. The whole hierarchy is a single record as far as Lucene is concerned, so when a spatial query such as flightline intersects bounding box is performed, GN will return the whole sortie. Not a great problem for aerial photography sorties which tend (for us) to be over a relatively small area.

The other way I have modelled hierarchies which doesn't suffer from this problem is to use the hierarchyLevel and parentIdentifier elements in gmd:MD_Metadata. This is very simple, if a bit painful to edit in the GN admin interface (you have to keep track of UUIDs). I have found this approach much better for automatically batch imported metadata rather than data entered manually.

Hope this helps,

David Herbert
British Antarctic Survey.

-----Original Message-----
From: andrew walsh [mailto:awalsh@anonymised.com]
Sent: 03 August 2010 04:17
To: geonetwork-users@lists.sourceforge.net
Cc: geonetwork-devel@lists.sourceforge.net
Subject: [GeoNetwork-users] Examples of use of the aggregationInfo element?

Hi GN community,

I would be very interested to see real examples where people
have used the aggregationInfo element of ISO19115.

We are considering using the element to store hierarchical information
or to identify particular 'facilities' which gathered the data.

Any XML samples of metadata records or pointers to them
would be greatly appreciated.

Regards,

Andrew
------------------------------------------------------------------------------
The Palm PDK Hot Apps Program offers developers who use the
Plug-In Development Kit to bring their C/C++ apps to Palm for a share
of $1 Million in cash or HP Products. Visit us here for more details:
http://p.sf.net/sfu/dev2dev-palm
_______________________________________________
GeoNetwork-users mailing list
GeoNetwork-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geonetwork-users
GeoNetwork OpenSource is maintained at http://sourceforge.net/projects/geonetwork