ISO Identification Information
The MD_IdentificationInformation Object is an Abstract Object that holds general identification information for all kinds of objects. It is required and there can be any number of these objects in an MD_Metadata container. At present the MD_Identification Object can be instantiated either as a MD_DataIdentification Object, for datasets, or a MD_ServiceIdentification Object, for services.
The MD_Identification Object includes six simple elements shown inside the box in the Figure and eight associated complex objects shown as boxes outside of the MD_Identification Object. The simple elements are primarily textual descriptions that might be presented to users in a summary document or searched using full-text search mechanisms. The organizational/human contact is also included. The complex objects are described in more detail below.
+ citation : CI_Citation + abstract : CharacterString + purpose [0..1] : CharacterString + credit [0..*] : CharacterString + status [0..*] : MD_ProgressCode + pointOfContact [0..*] : CI_ResponsibleParty + resourceMaintenance [0..*] : MD_MaintenanceInformation + graphicOverview [0..*] : MD_BrowseGraphic + resourceFormat [0..*] : MD_Format + descriptiveKeywords [0..*] : MD_Keywords + resourceSpecificUsage [0..*] : MD_Usage + resourceConstraints [0..*] : MD_Constraints + aggregationInfo [0..*] : MD_AggregationInformation + spatialRepresentationType [0..*] : MD_SpatialRepresentationTypeCode + spatialResolution [0..*] : MD_Resolution + language [1..*] : CharacterString + characterSet [0..*] : MD_CharacterSetCode = "utf8" + topicCategory [0..*] : MD_TopicCategoryCode + environmentDescription [0..1] : CharacterString + extent [0..*] : EX_Extent + supplementalInformation [0..1] : CharacterString
Pictures are important tools for getting a quick impressions about datasets or services. The MD_BrowseGraphic Object provides simple descriptions of these pictures and information required to link to them. Note that ISO 19139 extends the CharacterString Type to be a Universal Resource Identifier (URI). This means that the FileName element can be a URI.
The MD_Usage Object tracks how the dataset is being used and limitations that particular users have encountered. This object is one that could be populated by users throughout the life of the dataset.
Scientific datasets can be grouped for many different reasons. The ISO Metadata Standard supports grouping of datasets and services (MD_IdentificationObjects) using the MD_AggregateInformation Object. This object identifies groups using a CI_Citation or an MD_Identifier and describes the nature of the group using association or initiative types (see Figure). See ISO Aggregations for examples.