Tree structures
Each node is associated with a temporal operator and each leaf represents a basic object. The set of temporal operators depends on the system.
CMIF:
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Proposes both sequential and parallel operators. |
SRT:
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Has sequential and equal operators. |
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equal operators - the operands start simultaneously and must have the same duration. |
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static checking phase is used to verify that the operands of an equal operator have the same duration. |
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SRT is not able to deal with unpredictable events. |
SMIL:
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Have more advanced set of operators to express interruptions like Par_min. |
Authoring Capabilities:
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It is not straightforward to get the tree structure from the scenario. |
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Figure 6(a) illustrates the Company part of the document example, using SRT. The only way to get a tree structure is to fix the delay between the beginning of History and Geography. Notice that the temporal information between Geography and Name is lost. |
Synchronization Arcs in CMIF:
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Allows additional temporal information between any pair of nodes of the tree. |
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Figure 6(b), shows a Synchronization Arc from Name to Geography specifying a delay of 20 s. |
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Semantics of Synchronization Arcs is unclear. Figure 6(c), What happens if the A is longer than 20 s? |
