The development of modern distributed software systems poses a significant engineering challenge. The system architecture should exhibit plasticity and high degree of reconfigurability to enable an automated adaptation to continuously changing operating conditions and component failures. Traditional engineering approaches are inefficient to cope with complexity of such systems to ensure their r...

The aircraft environmental control system (ECS) is a critical aircraft system, which provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have received increasing attention in recent years. The heat exchanger is a particularly significant component of the ECS, because its failure decreases the sy...

Model-based fault isolation and identification in hybrid systems is computationally expensive or even unfeasible for complex systems due to the presence of uncertainty concerning the actual state, and also due to the presence of both discrete and parametric faults coupled with changing modes in the system. In this work we improve fault isolation and identification performance for hybrid systems...

This article deals with a distributed, fault-tolerant real-time application modeling by timed automata. The application under consideration consists of several processors communicating via Controller Area Network (CAN); each processor executes an application that consists of fault-tolerant tasks running under an operating system (e.g. OSEK) and using inter-task synchronization primitives. For s...

ÐThis paper describes a new comparison-based model for distributed fault diagnosis in multicomputer systems with a weak reliable broadcast capability. The classical problems of diagnosability and diagnosis are both considered under this broadcast comparison model. A characterization of diagnosable systems is given, which leads to a polynomial-time diagnosability algorithm. A polynomial-time dia...

Roll-Forward Checkpointing Schemes combine fault-detectionusing duplicated processes and checkpoints with a characteristic fault-treatment strategy. In existing schemes, faults of single processes are detected by checkpoint-comparison, localized and eliminated by a retry-execution on a spare processor and lookahead execution in parallel. The main advantage of these schemes is a completion time ...

Finite failure NHPP models proposed in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault, and are inadequate to describe the failure process underlying certain failure data sets. In this paper, we propose the loglogistic reliability growth model, which can capture the increasing=decreasing nature of the failure occurrence rat...

In this paper, a two-level reconfiguration action is used to design an FTC system. The objective is to adapt the corrective action accordingly to the fault severity. The first level of the procedure is triggered when the impact of the fault on the system performance is limited. At the second level a dynamic reference modification based on reference-offset governor is proposed. The idea consists...

Fault-tolerant solutions greatly benefit the dependability of robotic systems. This advantage is critical for robotic systems that perform in collaboration with humans. This work addresses the fault tolerance of robotic manipulators for cooperatively manipulating an object together with a human. Cooperation occurs for slow lifting or pushing of the object. Reconfiguration of the manipulator is ...