List of Figures

• Example of an X-t diagram.
• Example of an X-t diagram.
• Model dependency diagram for the global task.
• Model dependency diagram for the global task, including user.
• Design by decomposition.
• Problem decomposition hierarchy.
• Refined model dependency diagram.
• Model dependency diagram for the two step decomposition.
• Adding the domain model with the passenger relations.
• Selecting an engine which will drive a sequence.
• Selecting the first train of a sequence.
• Extending a sequence.
• Specifying a sequence: detailed view.
• Construction of plan case models for basic problems.
• Re-composition of subsolutions.
• Model dependency diagram for the first re-composition.
• Final re-composition.
• Final model dependency diagram.
• First level of the task structure.
• Decomposition of the task ``decompose problem into subproblems''.
• Decomposition of the task solve subproblems.
• Decomposition of the task ``specify sequence''.
• Decomposition of the task ``recompose''.
• Final task structure.
• Control diagram for the first level of the task structure.
• Control diagram for the subtasks of the task ``decompose problem''.
• Control diagram for the task which solves a subproblem.
• Control diagram for specification of a sequence.
• Control diagram for the re-composition.

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