type MembershipFunctionTypes = enumeration(ramp "Bounded ramp function", triangular "Triangular function", trapezoidal "Trapezoidal function", sshaped "S-shaped function", sigmoidal "Sigmoidal membership function", pishaped "Pi-shaped membership function", psigmoidal "Product of two sigmoidal membership functions", gaussian "Gaussian membership function", bell "Bell-shaped membership function");