A conceptual design of a model-based fault detection and diagnosis system is developed for the Space Shuttle main engine. The design approach consists of process modeling, residual generation, and fault detection and diagnosis. The engine is modeled using a discrete time, quasilinear state-space representation. Model parameters are determined by identification. Residuals generated from the mode...

studying active faults behavior for earthquake prediction and recognition is a concentrated subject in earth science. precise measurements of earthsurface deformation by geodetic observation provide a good reference for studying different geodynamic phenomena.  applying geodetic measurements in postseismic and interseismic intervals is an important tool for estimating strain accumulation and rh...

The reliability models often assume random testing and statistical independence of faults to keep the analysis tractable. In practice, these assumptions do not hold. This paper presents a reliability modeling approach that considers nonrandom testing. This approach is used to calculate the fault exposure ratio, which characterizes the testing process. The analysis of the experimental data sugge...

We discuss the modeling and verification of real-time systems using the SAL model checker. A new modeling framework based on event calendars enables dense timed systems to be described without relying on continuously varying clocks. We present verification techniques that rely on induction and abstraction, and show how these techniques are efficiently supported by the SAL symbolic model-checkin...

An important aspect of developing models relating the number and type of faults in a software system to a set of structural measurement is defining what constitutes a fault. By definition, a fault is a structural imperfection in a software system that may lead to the system’s eventually failing. A measurable and precise definition of what faults are makes it possible to accurately identify and ...

MEMS structures rendered defective by particles are modeled at the schematic-level using existing models of fault-free MEMS primitives within the nodal simulator NODAS. We have compared the results of schematic-level fault simulations with low-level finite element analysis (FEA) and demonstrated the efficacy of such an approach. Analysis shows that NODAS achieves a 60X speedup over FEA with lit...

The interest of microelectronic fluidic arrays for biomedical applications, like DNA determination, is rapidly increasing. In order to evaluate these systems in terms of required Design-for-Test structures, fault simulations in both fluidic and electronic domains are necessary. VHDL-AMS can be used successfully in this case. This paper shows a highly testable architecture of a DNA Bio-Sensing a...

The article focuses on the defects modeling of secured CMOS circuits, implemented in Quasi Delay Insensitive (QDI). We analyze the static and the dynamic behavior of resistive bridges as a function of its unpredictable resistance. SPICE simulations were performed for 45nm CMOS technology. Simulation results are given for the conditions of defect detection and for the delay induced by the resist...

This paper addresses the problem of fault detection and isolation of wind turbines using a mixed Bayesian/Setmembership approach. Modeling errors are assumed to be unknown but bounded, following the set-membership approach. On the other hand, measurement noise is also assumed to be bounded, but following a statistical distribution inside the bounds. To avoid false alarms, the fault detection pr...

The reliability models often assume random testing and statistical independence of faults to keep the analysis tractable. In practice, these assumptions do not hold. This paper presents a reliability modeling approach that considers nonrandom testing. This approach is used to calculate the fault exposure ratio, which characterizes the testing process. The analysis of the experimental data sugge...