A unified algebraic view of structured systems development models

Numerous models ha ve been proposed under the name of structured systems de velopment. Examples are data flo w diagrams [7, 10], Jackson structure diagrams, Jackson structure text [14], system specification diagrams, system implementation diagrams [15], Warnier/Orr diagrams [17], and Yourdon structure charts [22]. They are widely accepted by practising systems de velopers through the simplicity of use and the ease of communication with users. But because of the lack of a common theoretical frame work, transition from one model to another is arbitrary and can only be done manually . Users tend to stick to a particular model not because of its superiority b ut because of familiarity . Automatic development aids tend to be ad hocand model-dependent.