ABSTRACT

In order to study complex human-machine systems it is necessary to use modeling approaches that are approximate in nature (Zadeh 1973; Karwowski 1983). Fuzzy systems methodologies allow accounting for human and human-artifact fuzziness, and, therefore, provide the necessary framework for successful modeling efforts in the ergonomics (Karwowski 1991; Karwowski and Mital 1986). As fuzziness occurs at all levels of human interactions with the outside environments, ranging from physical to cognitive tasks, it can be used as the model for humanartifact interactions. It can also help to explain the complex phenomena of human sensation, information processing, decision-making and communication and functioning (Karwowski 1991; 1992; Karwowski and Salvendy 1992).