Model Based Systems Engineering: Fundamentals and Methods

4

Semiotic Systems and Models

4.1. Introduction

In the two previous chapters (Chapters 2 and 3), we considered technological systems and knowledge systems as two particular kinds of systems belonging to the general systems gender, as well as their specific properties. In this chapter, we are going to consider a third kind of systems: systems of signs that connect systems of the second kind to systems of the first kind. We will begin by defining what we mean by a system of signs, or (it is the same) a semiotic system, and we will introduce the denotation relationship that connects concrete systems and designation relationships that connect concrete systems to abstract systems. We will also introduce the concepts of signification and truth of systems of signs, inherited from that of meaning and truth of knowledge systems. We will then present what we mean by a law statement such as a system of signs, on the one hand, in relation with a nomological proposition of a knowledge system and, on the other hand, in relation with a factual law of concrete systems. Once we have presented these concepts, we will define what is meant by a model of a type of systems, using the concept of injective morphism. We will classify two types of models [BUN 73], object models and theoretical models, by specifying the type of morphism to which each refers. We will show how theoretical models pave the way to simulation, and we will conclude on the concepts of representativeness of models and expressiveness ...