Evaluating Engineering Functions with Imprecise Quantities

There is an increased awareness of the benefits of modeling imprecision in engineering problems, but success is limited by two problems associated with the calculus of imprecision: (1) Solving equations for a parameter is difficult because the common operators of addition and multiplication lack true inverses. (2) The multiple occurrence of imprecise quantities in engineering functions can lead to incorrectly very imprecise results because each occurrence of the parameter is treated as a separate parameter with the same range rather than multiple occurrences of the same parameter. Results obtained in the area of interval analysis are extended to the area of the calculus of imprecision. New operators are defined for functions of imprecise quantities that alleviate these two obstacles, and thus provide a general framework for including imprecision directly in engineering calculations.