of the Dissertation

Internal combustion engines (ICEs) are widely used in many important fields. The valve train clearance of an ICE usually exceeds the normal value due to wear or faulty adjustment. This work aims at diagnosing the valve clearance fault based on the vibration signals measured on the engine cylinder heads. The non-stationarity of the ICE operating condition makes it difficult to obtain the nominal...

TTP/C and FlexRay are two protocols that have been designed for use in time-triggered systems for safety-critical applications. This paper investigates the fault-containment and error-detection mechanisms of safety-critical time-triggered systems that are based on these two protocols. The following critical failure modes of a fault-containment region are introduced and analyzed in detail: babbl...

Fault injection deals with the insertion or simulation of faults in order to test the robustness and fault tolerance of a software application [8]. Such measures are generally performed on software that is mission critical, to the extent that failure could have significant negative ramifications. Actual injection of faults can be performed either at compile time, when additional code is inserte...

Predictability and fault tolerance are major requirements for complex real-time systems, which are either safety or mission critical. Traditionally fault tolerant techniques were employed to tackle the problem of ensuring correctness in the value domain only. We stress that the fault tolerance requirements and timing constraints are not orthogonal issues as they appear to be, and hence any viab...

Recurrent Neural Networks (RNNs) can model temporal dependencies in time series well. In this paper we present an interesting application of stacked Gated Recurrent Unit (GRU) based RNN for early prediction of imminent instability in a power system based on normal measurements of power system variables over time. In a power system, disturbances like a fault can result in transient instability w...

In high assurance avionics systems, such as systems for flight guidance, air traffic control, and collision avoidance, compelling evidence is required that the system behavior satisfies certain critical properties. Some critical properties are functional properties, properties of the services that the system delivers. For example, when another aircraft flies too close, a collision avoidance sys...