Structured Analysis and Design Technique
What is it good for ?
- to define user needs for IT developments (which is very used in the industrial Information Systems)
- to explain and to present an activity’s manufacturing processes, procedure
- A main box where the name of the process or the action is specified
- On the left-hand side of this box, incoming arrows: inputs of the action.
- On the upper part, the incoming arrows: data necessary for the action.
- On the bottom of the box, incoming arrows: means used for the action.
- On the right-hand side of the box, outgoing arrows: outputs of the action.
The semantics of arrows for activities:
- Inputs enter from the left and represent data or consumables that are needed by the activity.
- Outputs exit from the right and represent data or products that are produced by the activity.
- Controls enter from the top and represent commands which influence the execution of an activity but are not consumed.
- Mechanisms identify the means, components or tools used to accomplish the activity. Represents allocation of activities.
The semantics of arrows for data:
- Inputs are activities that produce the data.
- Outputs consume the data.
- Controls influence the internal state of the data