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All Outputs (9)

Petri Nets and Pseudo-Bond Graphs for a Nuclear Reactor Primary Coolant System (2019)
Presentation / Conference Contribution
Wootton, M. J., Andrews, J., Lloyd, A. L., Smith, R., Arul, A. J., Vinod, G., Prasad, S. H., & Garg, V. (2019, September). Petri Nets and Pseudo-Bond Graphs for a Nuclear Reactor Primary Coolant System. Presented at 29th European Safety and Reliability Conference (ESREL 2019), Hannover, Germany

In this paper we demonstrate the application of timed Petri Net methodology to the frequency of initiating faults in the coolant circulation system of a fictional nuclear reactor design. A second model is presented where the Petri Net is coupled with... Read More about Petri Nets and Pseudo-Bond Graphs for a Nuclear Reactor Primary Coolant System.

Nuclear Facilities and Cyber Threats (2019)
Presentation / Conference Contribution
Tolo, S., & Andrews, J. (2019, September). Nuclear Facilities and Cyber Threats. Presented at 29th European Safety and Reliability Conference (ESREL 2019), Hannover, Germany

The exponential growth of digital technologies experienced in the last decades has shaped contemporary societies so thoroughly to earn the definition of digital revolution or third industrial revolution. Along with the penetration rate of digital tec... Read More about Nuclear Facilities and Cyber Threats.

A petri net methodology for modelling the maintenance of railway route sections (2019)
Presentation / Conference Contribution
Litherland, J., & Andrews, J. (2019, September). A petri net methodology for modelling the maintenance of railway route sections. Presented at 29th European Safety and Reliability Conference (ESREL 2019), Hannover, Germany

Railway utilization is increasing. In 2017-18 there were over 1.7 billion passenger journeys made on the UK railway network, more than double the number made in 1995. Therefore getting maximum performance from the existing network by streamlining mai... Read More about A petri net methodology for modelling the maintenance of railway route sections.

Efficient risk based optimization of large system models using a reduced petri net methodology (2019)
Presentation / Conference Contribution
Naybour, S., Andrews, J., & Chiachio-Ruano, M. (2019, September). Efficient risk based optimization of large system models using a reduced petri net methodology. Presented at 29th European Safety and Reliability Conference (ESREL 2019), Hannover, Germany

The methodology presented in this paper is a two-stage optimization approach that can be applied to large system level models, in this case using a Stochastic Petri Net (SPN) framework, to produce an equivalent model response at a reduced computation... Read More about Efficient risk based optimization of large system models using a reduced petri net methodology.

Development of an extended RAMS framework for railway networks (2019)
Presentation / Conference Contribution
Litherland, J., Calvert, G., Andrews, J., & Kirwan, A. (2019, September). Development of an extended RAMS framework for railway networks. Presented at 29th European Safety and Reliability Conference (ESREL 2019), Hannover, Germany

Railway asset managers have finite resources which requires them to make strategic decisions on where, when and how the available budget will be spent on the railway, while ensuring safety limits are maintained and a high level of performance is deli... Read More about Development of an extended RAMS framework for railway networks.

Optimising Rail Replacement Bus Services During Infrastructure Possessions (2019)
Journal Article
Meesit, R., & Andrews, J. (2019). Optimising Rail Replacement Bus Services During Infrastructure Possessions. Infrastructure Asset Management, https://doi.org/10.1680/jinam.18.00042

Providing rail-replacement bus services is a common strategy applied to handle track blockage situations in railway networks. Previously, a great deal of research has focused on modelling this strategy, particularly in the case of unplanned disruptio... Read More about Optimising Rail Replacement Bus Services During Infrastructure Possessions.

Modelling the effect of hydrogen on crack growth in zirconium (2019)
Journal Article
Lloyd, A. L., Smith, R., Wootton, M. J., Andrews, J., Arul, J., Muruva, H. P., & Vinod, G. (2019). Modelling the effect of hydrogen on crack growth in zirconium. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 455, 13-20. https://doi.org/10.1016/j.nimb.2019.06.017

Via molecular dynamics simulations, the effects of hydrogen on stress evolution of -zirconium and crack propagation in monocrystalline and multiple grained zirconium systems are investigated. Diffusion barriers are shown to reduce when strain is appl... Read More about Modelling the effect of hydrogen on crack growth in zirconium.

An efficient algorithm for computing exact system and survival signatures of K-terminal network reliability (2019)
Journal Article
Reed, S., Löfstrand, M., & Andrews, J. (2019). An efficient algorithm for computing exact system and survival signatures of K-terminal network reliability. Reliability Engineering and System Safety, 185, 429-439. https://doi.org/10.1016/j.ress.2019.01.011

An efficient algorithm is presented for computing exact system and survival signatures of K-terminal reliability in undirected networks with unreliable edges. K-terminal reliability is defined as the probability that a subset K of the network nodes c... Read More about An efficient algorithm for computing exact system and survival signatures of K-terminal network reliability.