Features of the Input Interface

• Increments of the input can be specified independently from each other and with a varying amount of information enclosed: I(t) is defined as a sequence of packages of information A1, A2, ..., An to be composed.
• Increments of the input can be handed over in any order and with arbitrarily long pauses between them. The order of elements is not interpreted as encoding information (e.g., about topic and focus)

The Input Interface Language

• Two types of packages of information:
  • ENTITY: for describing content words
  • RELATION: for describing semantic relations
• Unique reference names as labels for the packages ---> it is possible to hand over underspecified input and to complete it later on, each time using the same reference name.
• Example:
  ...
  (ENTITY VP-1 ((CAT V) (HEAD "meet") ... ))
  (ENTITY NP-1 ((CAT N) (HEAD "man") ... ))
  (RELATION REL-VP-1 ((REGENT VP-1) (DEP NP-1) (FUNC agent) ... ))
  ...

• Global task: Construction of the hierarchical representation of the actual sentence
• Feature Structure based Tree Adjoining Grammars for the representation of syntactic structures
• Realization of intra-component parallelism by using distributed adjunction and substitution: The objects exchange copies of relevant feature structures.
• The effects of distributed substitution and adjunction are not limited to the two objects which are directy envolved. Changes in feature structures have to be propagated to the concerned objects.
• Introducing a local tree into the global syntactic tree is the prerequisite for changing to the positional level.

• Global task: Linearization of the global syntactic tree
• Realization of intra-component parallelism by linearizing local structures in parallel
• CDL-TAGs for the representation of linearization rules
• CDL-rules are interpreted according to the actual context
• If an adjunction takes place after local linearization, the linearization process is restarted

• Realization of intra-component parallelism by synchronizing the output activities of the single objects
• Late adjunctions lead to repair handling