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All Outputs (36)

Compositional synthesis of temporal fault trees from state machines (2012)
Journal Article
Papadopoulos, Y., Walker, M., & Mahmud, N. (2012). Compositional synthesis of temporal fault trees from state machines. Performance Evaluation Review, 39(4), 79-88. https://doi.org/10.1145/2185395.2185444

Dependability analysis of a dynamic system which is embedded with several complex interrelated components raises two main problems. First, it is difficult to represent in a single coherent and complete picture how the system and its constituent parts... Read More about Compositional synthesis of temporal fault trees from state machines.

Integrated safety and architecture modeling for automotive embedded systems (2011)
Journal Article
Chen, D., Johansson, R., Lönn, H., Blom, H., Walker, M., Papadopoulos, Y., Torchiaro, S., Tagliabo, F., & Sandberg, A. (2011). Integrated safety and architecture modeling for automotive embedded systems. Elektrotechnik und Informationstechnik : E & I, 128(6), 196-202. https://doi.org/10.1007/s00502-011-0007-7

EAST-ADL is an architecture description language (ADL) for model-based development of automotive embedded systems. The formalization of domain-specific engineering information and methodology brings a potential for a wide range of benefits for inform... Read More about Integrated safety and architecture modeling for automotive embedded systems.

A hierarchical method for the reduction of temporal expressions in Pandora (2010)
Presentation / Conference Contribution
Papadopoulos, Y., & Walker, M. A hierarchical method for the reduction of temporal expressions in Pandora. Presented at Proceedings of the First Workshop on DYnamic Aspects in DEpendability Models for Fault-Tolerant Systems - DYADEM-FTS '10

Fault Tree Analysis (FTA) is a popular safety analysis technique used to determine the logical combination of events needed to cause a particular system failure. However, FTA is purely combinatorial and cannot analyse the effects of sequences of even... Read More about A hierarchical method for the reduction of temporal expressions in Pandora.

Automatic allocation of safety integrity levels (2010)
Presentation / Conference Contribution
Papadopoulos, Y., Walker, M., Reiser, M.-O., Weber, M., Chen, D., Törngren, M., Servat, D., Abele, A., Stappert, F., Lonn, H., Berntsson, L., Johansson, R., Tagliabo, F., Torchiaro, S., & Sandberg, A. (2010, April). Automatic allocation of safety integrity levels. Presented at Proceedings of the 1st Workshop on Critical Automotive applications Robustness & Safety - CARS '10

In this paper, we describe a concept for the automatic allocationof general Safety Integrity Levels (SILs) to subsystems andcomponents of complex hierarchical networked architectures thatdeliver sets of safety critical functions. The concept is gener... Read More about Automatic allocation of safety integrity levels.

Capture and reuse of composable failure patterns (2010)
Journal Article
Wolforth, I., Walker, M., Papadopoulos, Y., & Grunske, L. (2010). Capture and reuse of composable failure patterns. International Journal of Critical Computer-Based Systems, 1(1/2/3), 128-147. https://doi.org/10.1504/IJCCBS.2010.031710

Emerging safety analysis techniques use composition of failure models or fault simulation in formal models of a system to determine relationships between the causes and effects of failure. Most recent work has focused on developing system modelling a... Read More about Capture and reuse of composable failure patterns.

Engineering failure analysis and design optimisation with HiP-HOPS (2010)
Journal Article
Papadopoulos, Y., Walker, M., Parker, D., Rüde, E., Hamann, R., Uhlig, A., Grätz, U., & Lien, R. (2011). Engineering failure analysis and design optimisation with HiP-HOPS. Engineering Failure Analysis, 18(2), 590-608. https://doi.org/10.1016/j.engfailanal.2010.09.025

The scale and complexity of computer-based safety critical systems, like those used in the transport and manufacturing industries, pose significant challenges for failure analysis. Over the last decade, research has focused on automating this task. I... Read More about Engineering failure analysis and design optimisation with HiP-HOPS.

A translation of state machines to temporal fault trees (2010)
Presentation / Conference Contribution
Papadopoulos, Y., Mahmud, N., & Walker, M. (2010, June). A translation of state machines to temporal fault trees. Presented at 2010 International Conference on Dependable Systems and Networks Workshops (DSN-W)

State Machines (SMs) are increasingly being used to gain a better understanding of the failure behaviour of safety-critical systems. In dependability analysis, SMs are translated to other models, such as Generalized Stochastic Petri Nets (GSPNs) or c... Read More about A translation of state machines to temporal fault trees.

Generalizable safety annotations for specification of failure patterns (2010)
Journal Article
Papadopoulos, Y., Walker, M., Grunske, L., & Wolforth, I. (2010). Generalizable safety annotations for specification of failure patterns. Software: Practice and Experience, 40(5), 453-483. https://doi.org/10.1002/spe.966

Components in programmable systems often exhibit patterns of failure that are independent of function or system context. In this paper, we show that it is possible to capture, and reuse where appropriate, such patterns for the purposes of system safe... Read More about Generalizable safety annotations for specification of failure patterns.

Qualitative temporal analysis: Towards a full implementation of the Fault Tree Handbook (2009)
Journal Article
Papadopoulos, Y., & Walker, M. (2009). Qualitative temporal analysis: Towards a full implementation of the Fault Tree Handbook. Control engineering practice, 17(10), 1115-1125. https://doi.org/10.1016/j.conengprac.2008.10.003

The Fault tree handbook has become the de facto standard for fault tree analysis (FTA), defining the notation and mathematical foundation of this widely used safety analysis technique. The Handbook recognises that classical combinatorial fault trees... Read More about Qualitative temporal analysis: Towards a full implementation of the Fault Tree Handbook.

Semi-automatic FMEA supporting complex systems with combinations and sequences of failures (2009)
Journal Article
Walker, M., Papadopoulos, Y., Parker, D., Lönn, H., Törngren, M., Chen, D., Johannson, R., & Sandberg, A. (2009). Semi-automatic FMEA supporting complex systems with combinations and sequences of failures. SAE International Journal of Passenger Cars - Mechanical Systems, 2(1), 791-802. https://doi.org/10.4271/2009-01-0738

Failure Modes and Effects Analysis (FMEA) is a well established safety analysis technique used for the assessment of safety critical engineering systems in the automotive industry. Although FMEA has been shown to be useful, the analysis is typically... Read More about Semi-automatic FMEA supporting complex systems with combinations and sequences of failures.

A language for failure patterns and application in safety analysis (2008)
Presentation / Conference Contribution
Wolforth, I., Walker, M., & Papadopoulos, Y. A language for failure patterns and application in safety analysis. Presented at 2008 Third International Conference on Dependability of Computer Systems DepCoS-RELCOMEX

Components and families of components in mechatronic systems often exhibit failure characteristics that are independent of system context and repeatable across applications. In this paper, we show that it is possible to capture and reuse such pattern... Read More about A language for failure patterns and application in safety analysis.

Semi automatic failure analysis based on simulation models (2008)
Presentation / Conference Contribution
Hamann, R., Uhlig, A., Papadopoulos, Y., Rüde, E., Grätz, U., Walker, M., & Lien, R. (2018, June). Semi automatic failure analysis based on simulation models. Presented at Volume 2: Structures, Safety and Reliability

Classical risk assessment and risk management which is gaining importance in many industries is usually based on well defined processes and uses techniques like FTA and FMEA. However, classical risk analysis techniques like FTA and FMEA should ideall... Read More about Semi automatic failure analysis based on simulation models.

Synthesis and analysis of temporal fault trees with PANDORA: the time of Priority AND gates (2007)
Journal Article
Walker, M., & Papadopoulos, Y. (2008). Synthesis and analysis of temporal fault trees with PANDORA: the time of Priority AND gates. Nonlinear Analysis: Hybrid Systems, 2(2), 368-382. https://doi.org/10.1016/j.nahs.2006.05.003

Classical Fault Tree Analysis (FTA) can determine the effects of combinations of failure events on a system but cannot capture the significance of the temporal order of events, which may be critical. In this paper, we propose an extension based on fo... Read More about Synthesis and analysis of temporal fault trees with PANDORA: the time of Priority AND gates.

Quantification of Simultaneous-AND Gates in Temporal Fault Trees
Presentation / Conference Contribution
Edifor, E., Walker, M., & Gordon, N. Quantification of Simultaneous-AND Gates in Temporal Fault Trees

Fault Tree Analysis has been a cornerstone of safety-critical systems for many years. It has seen various extensions to enable it to analyse dynamic behaviours exhibited by modern systems with redundant components. However, none of these extended FTA... Read More about Quantification of Simultaneous-AND Gates in Temporal Fault Trees.

Quantification of priority-OR gates in temporal fault trees
Presentation / Conference Contribution
Edifor, E., Walker, M., & Gordon, N. Quantification of priority-OR gates in temporal fault trees

Fault Tree Analysis has been used in reliability engineering for many decades and has seen various modifications to enable it to analyse fault trees with dynamic and temporal gates so it can incorporate sequential failure in its analysis. Pandora is... Read More about Quantification of priority-OR gates in temporal fault trees.

Using simulation to evaluate dynamic systems with weibull or lognormal distributions
Presentation / Conference Contribution
Edifor, E., Gordon, N., Walker, M., & Papadopoulos, Y. Using simulation to evaluate dynamic systems with weibull or lognormal distributions. Presented at Ninth International Conference on Dependability and Complex Systems DepCoS-RELCOMEX, Brunów, Poland

© Springer International Publishing Switzerland 2014. Most techniques for quantitatively analysing the temporal fault trees of safety-critical systems are used with the assumption that the systems under study have exponentially distributed component... Read More about Using simulation to evaluate dynamic systems with weibull or lognormal distributions.