3. Design phases and inverse model approach

This section presents a series of problems that can be encountered in design. Each is described in terms of the problem posed, the problem data and the objective sought. In each case, the proposed approach to solving these problems is based on the desire to use the problem data, i.e. the specifications, from the outset. This approach leads us to manipulate the models with these specifications as inputs; yet they generally express what is desired as an output from the system to be designed. It is therefore natural to approach these models in reverse, where the (specified) outputs become inputs for the models.

The order of the issues presented corresponds to a chronological breakdown of the design process. Some may not be covered, depending on the constraints of the study and the choices made a priori in terms of technology, for example. Each of the following paragraphs...