Modeling of systems with ill-defined attributes

In the study of an object or a system, one must first of all describe it through interrelating the variables which are considered most relevant to the modeling of the system. However in many cases, the attributes of a system are ambiguous as in the case of handwritten characters; for there is no clear-cut definition of, say, handwritten "five". The characters "5", "5", "5", and "5" are somehow all recognized as "five". For machine recognition of this seemingly ill-defined object, it is necessary to be able to describe it analytically. One attempt is made in this paper to model the handwritten characters. The handwritten characters are directed graphs[1], the branch set of which are fuzzily classified to the branch types such as straight lines, circles and parts of a circle; the branch types in turn are considered as fuzzy variables[2]. A fuzzy function is then synthesized to model each handwritten character by relating fuzzy variables.