An introduction to the MEDIN Discovery Metadata Standard

What is metadata and what should I do with it?

Put simply, discovery metadata is information about a data set. For example, a metadata record typically contains information about the title of a data set, the geographic scope, when it was last updated and the contact details of the person who owns it.

Put another way, discovery metadata provides information about, or documentation of, datasets managed within an organisation or application.

Used to describe datasets (or series or services) so that a user can easily discover them using a portal and find details to where he/she can access them

Standard composed of ‘elements’ (e.g. title, begin date, contact, access conditions)

XML is used to encode the record so that it becomes machine readable.

MEDIN has produced a guidance document, validation tool (schematron) and tools to create and test metadata records

Discovery Metadata Standard

http://www.oceannet.org/marine_data_standards/medin_disc_stnd.html

Discovery Metadata Standard - Introduction

Discovery Metadata Standard - Guidance

Compliant with the ISO19115 (Geographic information – Metadata), INSPIRE and UK GEMINI2 and uses the ISO 19139 schema set for encoding xml

Short, simple version available!

The MEDIN standard specifies use of certain vocabularies (term lists) to make it ‘marine flavoured’

•Keywords: SeaDataNet parameter discovery vocab (e.g. Fish taxonomy related counts; temperature of the water column)

•Keywords: SeaDataNet vertical coverage terms (e.g. epipelagic; benthic boundary layer)

•Spatial Reference System: European Petroleum Survey Group (EPSG) geodetic parameters (e.g. EPSG::4326)

•Data format: MEDIN (e.g. delimited; image; GIS)

•Organisations: SeaDataNet European Directory of Marine Organisations (EDMO)

Discovery Metadata Standard - Marine

1. On-line metadata generation/editing tool

Discovery Metadata Standard - Tools

2. Desktop tool – Metadata Meastro. Can work in stand alone mode. Soon to be extended to GEMINI2.

3. A tool which will assist in transforming already populated metadata databases into MEDIN format XML metadata. Designed so that organisations who hold their own metadata can transfer their data into this structure from which a tool can be applied to produce xml records. Guidance document available.

4. Specific tools for GIS users: Stylesheet for transforming ArcCat ESRI ISO standard metadata to MEDIN standard. Arc 9 stylesheet no longer supported. Arc 10 stylesheet now available.

Discovery Metadata Standard - Tools

Important to be able to test the structure and content of the xml records once produced to ensure that they comply with the standard.

A Schematron has been developed (compliant with ISO 19757 (Part 3) Information technology -- Document Schema Definition Languages (DSDL) -- Part 3: Rule-based validation – Schematron).

Used in many different circumstances and tools so that if the standard changes it only requires one update rather than various validation methods for different applications

This schematron ‘sits’ at the end of the on-line metadata editor tool in a validation step. Can be used by organisations to test transfer between metadata holdings.

Discovery Metadata Standard - Validation

Guidance document on the schematron – technical

Guidance document on using the schematron in software ‘Oxygen’ - aimed at more lay user.

Discovery Metadata Standard - Schematron

What is a dataset?

• All metadata records can be harvested (and produced primarily for) by the portal.

• It is important that the portal is not swamped with records or not rich enough to be useful to the user

• MEDIN guidance on website

What is a dataset?

• the correct level for a dataset is a cruise, survey or a set of repeat observations with a common purpose,

• a data set usually constitutes a specifically-funded piece of work,

• the dataset should be easily extractable from a database for a 3rd party,

• if you are searching for a data set using a portal and get the result every time you search by different combinations of time, location and parameter then it is probably too coarse.

Updating the MEDIN discovery standard

• Standards evolve!

• MEDIN has placed itself to be close to, and feed into, any changes in standard that could influence our own.

• Members of the MEDIN standards WG also are represented on various Location Programme, INSPIRE and BSI groups.

• Sign up to the e-mail list to be kept up to date of changes