This concept describes the Person and Group Database (yellow) and the Tracking and Tracing Database (green) for a Victim Identification, Tracking and Tracing Framework (VITA) in Sahana.

The PersonEntity class represents logical appearances of persons, and will be implemented by Individual and Group subclasses. Common features of PersonEntities are Contact information, and the association of traceable items.

Association is a class candidate, which represents relationships between PersonEntity instances. The outline of Associations in the diagram above is probably misleading - its implementation is not fully clear yet:

Group Membership Approach:

Most likely, Associations get implemented as GroupMembership of Individuals (unidrectional, current Sahana), which would be the most efficient and most comprehensible way to handle relationships between PersonEntity instances. Moreover, this would probably be the most appropriate representation of role-based relationships in emergency management. In a GroupMembership implementation, Groups can be implicit (e.g. “Family” is an implicit group for to the Association type “Family Member”) and anonymous (defined only by their members).

Social Network Approach:

Alternatively, one could implement Associations as sets of bidirectional relationships between pairs of PersonEntity instances (as outlined in the diagram). This approach would surely be much more flexible, but would in turn require a much more sophisticated program logic (and thus be less efficient). Major advantage of this approach over the GroupMembership implementation would be the opportunity to represent relationships between groups (or any other pairing of PersonEntities).

Community Hierarchy Approach:

A possible middle course approach could be to extend GroupMembership to PersonEntities (i.e. Groups can be members of Groups, too).

The PersonItem class represents physical appearances of persons or their belongings that are traceable over time. A PersonItem will have 1 or more StatusTransition when it undergoes some Process Common features of PersonItems are Presence information, the association with Documents and Images, and a Role associated with them. Each PersonItem is given a Tag that can be as simple as a Label with some text/barcode on it or as complex as an RFID.

The Composition class represents the association of the PersonItems. One PersonItem can be a composed of other PersonItems that may have different Presence informations associated with them, undergoes different Processes

The Presence class represents all the tracking information about a PersonItem. It is composed of Location information over a TimeFrame, Each Presence has an Observer and a Reporter. At a Presence of a PersonItem there can be many StatusTransition associated with it due to the Process carried on it.

The Location class is composed of Address(street,city,state,country,postalcode) and GeoLocation(Latitude and Longitude for GIS Mapping)

The Image class will represent the images and documents associated with the PersonItem that can be located physically of digitally.