Dm2021 < IVOA

During Fall 2020 Interop we had a [[InterOpNov2020DM][session]], requested by Markus Demleitner, that aimed at opening a wide discussion on both Measure and Coordinate models and possibly at refining their usages.

This came after a long discussion on the mailing list, related to the necessity of keeping or not a tight dependancy between Measurements and Coordinates. It has also been suggested that product models (e.g. CubeDM ) could be replaced with domain related components.

Many people have participated to the discussion with many positive contributions. <br />Although the goal of this message is not to report on that meeting, we do need to note a few points:
   * There is a clear demand for using models
   * There is a clear demand for the models to be simple and modular.
   * The distinction between what is modelling and what is serialisation is unclear.
The need for a concrete solution for annotating catalog data, that resurfaced last week, has been tackled by the WG for a couple of years along with the development of Meas/Coordinates models.
   * 2018:<a target="_blank" href="SourceCatalogs">Discussions</a> have been engaged on this topic after a hands-on session in Victoria.
   * 2019: We asked data providers and client developers to [[InterOpMay2019DM][present]] their needs in a dedicated session at Paris
After these 2 surveys the scope of the model usage has been exposed in Virtual May 2020 and we have been working on MANGO (model for source data with some MC adaptations ) that has been sketched in Groningen and in virtual-May and then [[%PUBURL%/IVOA/InterOpNov2020DM/Mango_interopFall2020.pdf][presented]] in November 2020.

To continue this action we have been organising a virtual workshop (initially proposed by Tom to the TCG) with the hope of getting a widely accepted framework.

The idea is not to start afresh but to give to the participants the opportunity of matching their needs with the current proposals.

To get a clear picture of what has to be done, we propose to work with a variety concrete use cases, mostly taken out of the SourceDM proposal ( [[https://volute.g-vo.org/svn/trunk/projects/dm/SourceDM/][2016]]) and data samples provided by interested people.
---+++ Timeline
   * 2021 February 18: Public release of the use-case [[https://github.com/ivoa/dm-usecases][repository]].
   * 2021 February 24: Running meeting to present the process
   * 2021 March: People can look and contribute at the repository
   * 2021 April: Virtual Workshop.
---++ Running meeting(2x/02/2021)
   * Etherpad [[https://yopad.eu/p/dm_virtual_meeeting_#2-365days][link]]
   * Zoom link
The purpose of this meeting is to prepar the workshop:

   * Presentation of the goals
   * Presentation of the use-case repository
   * Discussion on the best way to run it
   * Agreement on a date
This topic: IVOA > WebHome > IvoaDataModel > SourceCatalogs > Dm2021
Topic revision: r1 - 2021-02-19 - LaurentMichel