In order to improve the reliability and security of the system operation,fault detection(FD)technology has become an indispensable part of the technical process.All faults can be classified as either additive faults or multiplicative faults.Additive faults appear,e.g.,as offsets of sensors,whereas multiplicative faults are parameter changes within a process.In this paper,a new parametric fault model based on systems with multiplicative noise is proposed.Based on the constant gain filter,the authors study th...