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Outputs (77)

Explaining black boxes with a SMILE: Statistical Model-agnostic Interpretability with Local Explanations (2023)
Journal Article
Aslansefat, K., Hashemian, M., Walker, M., Akram, M. N., Sorokos, I., & Papadopoulos, Y. (2023). Explaining black boxes with a SMILE: Statistical Model-agnostic Interpretability with Local Explanations. IEEE Software, https://doi.org/10.1109/MS.2023.3321282

Machine learning is currently undergoing an explosion in capability, popularity, and sophistication. However, one of the major barriers to widespread acceptance of machine learning (ML) is trustworthiness: most ML models operate as black boxes, their... Read More about Explaining black boxes with a SMILE: Statistical Model-agnostic Interpretability with Local Explanations.

Towards Improving Confidence in Autonomous Vehicle Software: A Study on Traffic Sign Recognition Systems (2021)
Journal Article
Aslansefat, K., Kabir, S., Abdullatif, A., Vasudevan Nair, V., & Papadopoulos, Y. (in press). Towards Improving Confidence in Autonomous Vehicle Software: A Study on Traffic Sign Recognition Systems. Computer,

The application of artificial intelligence (AI) and data-driven decision-making systems in autonomous vehicles is growing rapidly. As autonomous vehicles operate in dynamic environments, the risk that they can face an unknown observation is relativel... Read More about Towards Improving Confidence in Autonomous Vehicle Software: A Study on Traffic Sign Recognition Systems.

Computational Intelligence for Safety Assurance of Cooperative Systems of Systems (2020)
Journal Article
Kabir, S., & Papadopoulos, Y. (2020). Computational Intelligence for Safety Assurance of Cooperative Systems of Systems. Computer, 53(12), 24-34. https://doi.org/10.1109/MC.2020.3014604

Cooperative systems of systems (CSoSs) form a new technological frontier for their enormous economic and societal potentials in various domains. This article presents a novel framework for dynamic safety assurance of CSoSs that integrates design time... Read More about Computational Intelligence for Safety Assurance of Cooperative Systems of Systems.

SafeML: Safety Monitoring of Machine Learning Classifiers Through Statistical Difference Measures (2020)
Journal Article
Aslansefat, K., Sorokos, I., Whiting, D., Tavakoli Kolagari, R., & Papadopoulos, Y. (2020). SafeML: Safety Monitoring of Machine Learning Classifiers Through Statistical Difference Measures. Lecture notes in computer science, 12297, 197-211. https://doi.org/10.1007/978-3-030-58920-2_13

Ensuring safety and explainability of machine learning (ML) is a topic of increasing relevance as data-driven applications venture into safety-critical application domains, traditionally committed to high safety standards that are not satisfied with... Read More about SafeML: Safety Monitoring of Machine Learning Classifiers Through Statistical Difference Measures.

An Integrated Approach to Support the Process-Based Certification of Variant-Intensive Systems (2020)
Journal Article
Bressan, L., de Oliveira, A. L., Campos, F., Papadopoulos, Y., & Parker, D. (2020). An Integrated Approach to Support the Process-Based Certification of Variant-Intensive Systems. Lecture notes in computer science, 12297 LNCS, 179-193. https://doi.org/10.1007/978-3-030-58920-2_12

© 2020, Springer Nature Switzerland AG. Component-based approaches and software product lines have been adopted by industry to manage the diversity of configurations on safety-critical software. Safety certification demands compliance with standards.... Read More about An Integrated Approach to Support the Process-Based Certification of Variant-Intensive Systems.

Failure Mode Reasoning in Model Based Safety Analysis (2020)
Journal Article
Jahanian, H., Parker, D., Zeller, M., McIver, A., & Papadopoulos, Y. (2020). Failure Mode Reasoning in Model Based Safety Analysis. Lecture notes in computer science, 12297 LNCS, 130-145. https://doi.org/10.1007/978-3-030-58920-2_9

© 2020, Springer Nature Switzerland AG. Failure Mode Reasoning (FMR) is a novel approach for analyzing failure in a Safety Instrumented System (SIS). The method uses an automatic analysis of an SIS program to calculate potential failures in parts of... Read More about Failure Mode Reasoning in Model Based Safety Analysis.

A Hybrid Modular Approach for Dynamic Fault Tree Analysis (2020)
Journal Article
Kabir, S., Aslansefat, K., Sorokos, I., Papadopoulos, Y., & Konur, S. (2020). A Hybrid Modular Approach for Dynamic Fault Tree Analysis. IEEE Access, 8, 97175-97188. https://doi.org/10.1109/ACCESS.2020.2996643

Over the years, several approaches have been developed for the quantitative analysis of dynamic fault trees (DFTs). These approaches have strong theoretical and mathematical foundations; however, they appear to suffer from the state-space explosion a... Read More about A Hybrid Modular Approach for Dynamic Fault Tree Analysis.

Model-Based Safety and Assessment: 6th International Symposium, IMBSA 2019, Thessaloniki, Greece, October 16–18, 2019, Proceedings (2019)
Conference Proceeding
(2019). Model-Based Safety and Assessment: 6th International Symposium, IMBSA 2019, Thessaloniki, Greece, October 16–18, 2019, Proceedings. In Y. Papadopoulos, K. Aslansefat, P. Katsaros, & M. Bozzano (Eds.), https://doi.org/10.1007/978-3-030-32872-6

This book constitutes the proceedings of the 6th International Symposium on Model-Based Safety and Assessment, IMBSA 2019, held in Thessaloniki, Greece, in October 2019. The 24 revised full papers presented were carefully reviewed and selected fr... Read More about Model-Based Safety and Assessment: 6th International Symposium, IMBSA 2019, Thessaloniki, Greece, October 16–18, 2019, Proceedings.

A conceptual framework to incorporate complex basic events in HiP-HOPS (2019)
Book Chapter
Kabir, S., Aslansefat, K., Sorokos, I., Papadopoulos, Y., & Gheraibia, Y. (2019). A conceptual framework to incorporate complex basic events in HiP-HOPS. In Y. Papadopoulos, K. Aslansefat, P. Katsaros, & M. Bozzano (Eds.), Model-Based Safety and Assessment. IMBSA 2019 (109-124). Cham: Springer Verlag. https://doi.org/10.1007/978-3-030-32872-6_8

Reliability evaluation for ensuring the uninterrupted system operation is an integral part of dependable system development. Model-based safety analysis (MBSA) techniques such as Hierarchically Performed Hazard Origin and Propagation Studies (HiP-HOP... Read More about A conceptual framework to incorporate complex basic events in HiP-HOPS.

A runtime safety analysis concept for open adaptive systems (2019)
Journal Article
Kabir, S., Sorokos, I., Aslansefat, K., Papadopoulos, Y., Gheraibia, Y., Reich, J., …Wei, R. (2019). A runtime safety analysis concept for open adaptive systems. Lecture notes in computer science, 11842, 332-346. https://doi.org/10.1007/978-3-030-32872-6_22

© Springer Nature Switzerland AG 2019. In the automotive industry, modern cyber-physical systems feature cooperation and autonomy. Such systems share information to enable collaborative functions, allowing dynamic component integration and architectu... Read More about A runtime safety analysis concept for open adaptive systems.

Dynamic reliability assessment of flare systems by combining fault tree analysis and Bayesian networks (2019)
Journal Article
Kabir, S., Taleb-Berrouane, M., & Papadopoulos, Y. (in press). Dynamic reliability assessment of flare systems by combining fault tree analysis and Bayesian networks. Energy Sources, Part A, https://doi.org/10.1080/15567036.2019.1670287

Flaring is a combustion process commonly used in the oil and gas industry to dispose flammable waste gases. Flare flameout occurs when these gases escape unburnt from the flare tip causing the discharge of flammable and/or toxic vapor clouds. The tox... Read More about Dynamic reliability assessment of flare systems by combining fault tree analysis and Bayesian networks.

Safety + AI: A novel approach to update safety models using artificial intelligence (2019)
Journal Article
Gheraibia, Y., Kabir, S., Aslansefat, K., Sorokos, I., & Papadopoulos, Y. (2019). Safety + AI: A novel approach to update safety models using artificial intelligence. IEEE Access, 7, 135855-135869. https://doi.org/10.1109/ACCESS.2019.2941566

Safety-critical systems are becoming larger and more complex to obtain a higher level of functionality. Hence, modeling and evaluation of these systems can be a difficult and error-prone task. Among existing safety models, Fault Tree Analysis (FTA) i... Read More about Safety + AI: A novel approach to update safety models using artificial intelligence.

Variability management in safety-critical systems design and dependability analysis (2019)
Journal Article
de Oliveira, A. L., Braga, R., Masiero, P., Parker, D., Papadopoulos, Y., Habli, I., & Kelly, T. (2019). Variability management in safety-critical systems design and dependability analysis. Journal of software : evolution and process, 31(8), Article e2202. https://doi.org/10.1002/smr.2202

Safety-critical systems are of paramount importance for many application domains, where safety properties are a key driver to engineer critical aspects and avoid system failures. For the benefits of large-scale reuse, software product lines (SPL) hav... Read More about Variability management in safety-critical systems design and dependability analysis.

Model transformation for analyzing dependability of AADL model by using HiP-HOPS (2019)
Journal Article
Mian, Z., Bottaci, L., Papadopoulos, Y., & Mahmud, N. (2019). Model transformation for analyzing dependability of AADL model by using HiP-HOPS. Journal of Systems and Software, 151, 258-282. https://doi.org/10.1016/j.jss.2019.02.019

The Architecture Analysis and Design Language (AADL) has emerged as a potential future standard in aerospace, automobile and avionics industries for model-based development of dependability-critical systems. As AADL is relatively new, some existing a... Read More about Model transformation for analyzing dependability of AADL model by using HiP-HOPS.

Applications of Bayesian networks and Petri nets in safety, reliability, and risk assessments: A review (2019)
Journal Article
Kabir, S., & Papadopoulos, Y. (2019). Applications of Bayesian networks and Petri nets in safety, reliability, and risk assessments: A review. Safety science, 115, 154-175. https://doi.org/10.1016/j.ssci.2019.02.009

System safety, reliability and risk analysis are important tasks that are performed throughout the system life-cycle to ensure the dependability of safety-critical systems. Probabilistic risk assessment (PRA) approaches are comprehensive, structured... Read More about Applications of Bayesian networks and Petri nets in safety, reliability, and risk assessments: A review.

Infinite Virtual Stoa (2018)
Conference Proceeding
Torrao, L., Papadopoulos, Y., & Mckie, D. (2018). Infinite Virtual Stoa. In XXI GENERATIVE ART 2018, proceedings of XXI Generative Art conference (183-194)

Stoicism is a philosophy that considers the object of life to be ataraxia (αταραξία), a state of psychological stability which is undisturbed by exposure to phenomena and circumstances that lie outside one's control. Such circumstances may include il... Read More about Infinite Virtual Stoa.

TIMAEUS: Three-dimensional Illuminated Media Augmented Sculptures (2018)
Conference Proceeding
Torrao, L., Mckie, D., & Papadopoulos, Y. (2018). TIMAEUS: Three-dimensional Illuminated Media Augmented Sculptures. In Proceedings of 20th Generative Art Conference,Soddu C. and Colabella E. (eds), Domus Argenia (459-469)

TIMAEUS is a digital art studio environment that enables creation of personalised 3-dimensional sculptures built with expanding spherical volumes or interconnected tetrahedra and possibly other atomic blocks in the future. These sculptures can be cus... Read More about TIMAEUS: Three-dimensional Illuminated Media Augmented Sculptures.

Explicit Modelling and Treatment of Repair in Prediction of Dependability (2018)
Journal Article
Aizpurua, J. I., Papadopoulos, Y., & Merle, G. (2018). Explicit Modelling and Treatment of Repair in Prediction of Dependability. IEEE Transactions on Dependable and Secure Computing, 17(6), 1147-1162. https://doi.org/10.1109/TDSC.2018.2857810

In engineering practice, multiple repair actions are considered carefully by designers, and their success or failure defines further control actions and the evolution of the system state. Such treatment is not fully supported by the current state-of-... Read More about Explicit Modelling and Treatment of Repair in Prediction of Dependability.

Uncertainty-aware dynamic reliability analysis framework for complex systems (2018)
Journal Article
Kabir, S., Yazdi, M., Aizpurua, J. I., & Papadopoulos, Y. (2018). Uncertainty-aware dynamic reliability analysis framework for complex systems. IEEE Access, 6, Article ACCESS2843166. https://doi.org/10.1109/ACCESS.2018.2843166

Critical technological systems exhibit complex dynamic characteristics such as time-dependent behaviour, functional dependencies among events, sequencing and priority of causes that may alter the effects of failure. Dynamic fault trees (DFTs) have be... Read More about Uncertainty-aware dynamic reliability analysis framework for complex systems.

A review of applications of fuzzy sets to safety and reliability engineering (2018)
Journal Article
Kabir, S., & Papadopoulos, Y. (2018). A review of applications of fuzzy sets to safety and reliability engineering. International Journal of Approximate Reasoning, 100, 29-55. https://doi.org/10.1016/j.ijar.2018.05.005

Safety and reliability are rigorously assessed during the design of dependable systems. Probabilistic risk assessment (PRA) processes are comprehensive, structured and logical methods widely used for this purpose. PRA approaches include, but not limi... Read More about A review of applications of fuzzy sets to safety and reliability engineering.

Timaeus: A digital art studio inspired by antiquity (2018)
Journal Article
Torrao, L., Papadopoulos, Y., & Mckie, D. (2018). Timaeus: A digital art studio inspired by antiquity. Generative art science and technology hard journal,

This project was motivated as an exploration of the capabilities provided by new digital media for creativity, art creation and art therapy. In the ancient Greek world, téchnē, the word for art, used to refer to both art and technology. The expressio... Read More about Timaeus: A digital art studio inspired by antiquity.

Model-based assessment of energy-efficiency, dependability, and cost-effectiveness of waste heat recovery systems onboard ship (2018)
Journal Article
Lampe, J., Rüde, E., Papadopoulos, Y., & Kabir, S. (2018). Model-based assessment of energy-efficiency, dependability, and cost-effectiveness of waste heat recovery systems onboard ship. Ocean engineering, 157, 234-250. https://doi.org/10.1016/j.oceaneng.2018.03.062

Technological systems are not merely designed with a narrow function in mind. Good designs typically aim at reducing operational costs, e.g. through achieving high energy efficiency and improved dependability (i.e. reliability, availability and maint... Read More about Model-based assessment of energy-efficiency, dependability, and cost-effectiveness of waste heat recovery systems onboard ship.

A Study of Automatic Allocation of Automotive Safety Requirements in Two Modes: Components and Failure Modes (2018)
Journal Article
Parker, D., Godof, A., Papadopoulos, Y., & Saintis, L. (2018). A Study of Automatic Allocation of Automotive Safety Requirements in Two Modes: Components and Failure Modes. SAE Technical Papers, 2018-April, https://doi.org/10.4271/2018-01-1076

ISO 26262 describes a safety engineering approach in which the safety of a system is considered from the early stages of design through a process of elicitation and allocation of system safety requirements. These are expressed as automotive safety in... Read More about A Study of Automatic Allocation of Automotive Safety Requirements in Two Modes: Components and Failure Modes.

Dynamic system safety analysis in HiP-HOPS with Petri Nets and Bayesian Networks (2018)
Journal Article
Papadopoulos, Y., Walker, M., & Kabir, S. (2018). Dynamic system safety analysis in HiP-HOPS with Petri Nets and Bayesian Networks. Safety science, 105, 55-70. https://doi.org/10.1016/j.ssci.2018.02.001

© 2018 Elsevier Ltd Dynamic systems exhibit time-dependent behaviours and complex functional dependencies amongst their components. Therefore, to capture the full system failure behaviour, it is not enough to simply determine the consequences of diff... Read More about Dynamic system safety analysis in HiP-HOPS with Petri Nets and Bayesian Networks.

DEIS: Dependability Engineering Innovation for Industrial CPS (2017)
Book Chapter
Armengaud, E., Macher, G., Massoner, A., Frager, S., Adler, R., Schneider, D., …Kelly, T. (2018). DEIS: Dependability Engineering Innovation for Industrial CPS. In C. Zachäus, B. Müller, & G. Meyer (Eds.), Advanced Microsystems for Automotive Applications 2017 : Smart Systems Transforming the Automobile (151-163). Cham: Springer. https://doi.org/10.1007/978-3-319-66972-4_13

The open and cooperative nature of Cyber-Physical Systems (CPS) poses new challenges in assuring dependability. The DEIS project (Dependability Engineering Innovation for automotive CPS. This project has received funding from the European Union’s Hor... Read More about DEIS: Dependability Engineering Innovation for Industrial CPS.

A model-based extension to HiP-HOPS for dynamic fault propagation studies (2017)
Journal Article
Kabir, S., Papadopoulos, Y., Walker, M., Parker, D., Aizpurua, J. I., Lampe, J., & Rüde, E. (2017). A model-based extension to HiP-HOPS for dynamic fault propagation studies. Lecture notes in computer science, 10437 LNCS, 163-178. https://doi.org/10.1007/978-3-319-64119-5_11

HiP-HOPS is a model-based approach for assessing the dependability of safety-critical systems. The method combines models, logic, probabilities and nature-inspired algorithms to provide advanced capabilities for design optimisation, requirement alloc... Read More about A model-based extension to HiP-HOPS for dynamic fault propagation studies.

Model-connected safety cases (2017)
Journal Article
Retouniotis, A., Papadopoulos, Y., Sorokos, I., Parker, D., Matragkas, N., & Sharvia, S. (2017). Model-connected safety cases. Lecture notes in computer science, 10437 LNCS, 50-63. https://doi.org/10.1007/978-3-319-64119-5_4

© 2017, Springer International Publishing AG. We propose the concept of a model-connected safety case that could simplify certification of complex systems. System design models support the synthesis of both the structure of the safety case and the ev... Read More about Model-connected safety cases.

Improved dynamic dependability assessment through integration with prognostics (2017)
Journal Article
Aizpurua, J. I., Catterson, V. M., Papadopoulos, Y., Chiacchio, F., & Manno, G. (2017). Improved dynamic dependability assessment through integration with prognostics. IEEE Transactions on Reliability, 66(3), 893-913. https://doi.org/10.1109/tr.2017.2693821

The use of average data for dependability assessments results in a outdated system-level dependability estimation which can lead to incorrect design decisions. With increasing availability of online data, there is room to improve traditional dependab... Read More about Improved dynamic dependability assessment through integration with prognostics.

Supporting group maintenance through prognostics-enhanced dynamic dependability prediction (2017)
Journal Article
Papadopoulos, Y., Aizpurua, J. I., Catterson, V. M., Chiacchio, F., D'Urso, D., Papadopoulos, Y., …D'Urso, D. (2017). Supporting group maintenance through prognostics-enhanced dynamic dependability prediction. Reliability Engineering and System Safety, 168, 171-188. https://doi.org/10.1016/j.ress.2017.04.005

Condition-based maintenance strategies adapt maintenance planning through the integration of online condition monitoring of assets. The accuracy and cost-effectiveness of these strategies can be improved by integrating prognostics predictions and gro... Read More about Supporting group maintenance through prognostics-enhanced dynamic dependability prediction.

On cost-effective reuse of components in the design of complex reconfigurable systems (2017)
Journal Article
Aizpurua, J. I., Papadopoulos, Y., Muxika, E., Chiacchio, F., & Manno, G. (2017). On cost-effective reuse of components in the design of complex reconfigurable systems. Quality and Reliability Engineering International, 33(7), 1387-1406. https://doi.org/10.1002/qre.2112

Design strategies that benefit from the reuse of system components can reduce costs while maintaining or increasing dependability—we use the term dependability to tie together reliability and availability. D3H2 (aDaptive Dependable Design for systems... Read More about On cost-effective reuse of components in the design of complex reconfigurable systems.

Fuzzy temporal fault tree analysis of dynamic systems (2016)
Journal Article
Kabir, S., Papadopoulos, Y., Walker, M., Rüde, E., & Securius, P. (2016). Fuzzy temporal fault tree analysis of dynamic systems. International Journal of Approximate Reasoning, 77, 20-37. https://doi.org/10.1016/j.ijar.2016.05.006

Fault tree analysis (FTA) is a powerful technique that is widely used for evaluating system safety and reliability. It can be used to assess the effects of combinations of failures on system behaviour but is unable to capture sequence dependent dynam... Read More about Fuzzy temporal fault tree analysis of dynamic systems.

A synthesis of logic and bio-inspired techniques in the design of dependable systems (2016)
Journal Article
Papadopoulos, Y., Walker, M., Parker, D., Sharvia, S., Bottaci, L., Kabir, S., …Sorokos, I. (2016). A synthesis of logic and bio-inspired techniques in the design of dependable systems. Annual Reviews in Control, 41, 170-182. https://doi.org/10.1016/j.arcontrol.2016.04.008

Much of the development of model-based design and dependability analysis in the design of dependable systems, including software intensive systems, can be attributed to the application of advances in formal logic and its application to fault forecast... Read More about A synthesis of logic and bio-inspired techniques in the design of dependable systems.

Application of the D3H2 methodology for the cost-effective design of dependable systems (2016)
Journal Article
Aizpurua, J. I., Muxika, E., Papadopoulos, Y., Chiacchio, F., & Manno, G. (2016). Application of the D3H2 methodology for the cost-effective design of dependable systems. Safety, 2(2), Article 9. https://doi.org/10.3390/safety2020009

The use of dedicated components as a means of achieving desirable levels of fault tolerance in a system may result in high costs. A cost effective way of restoring failed functions is to use heterogeneous redundancies: components that, besides perfor... Read More about Application of the D3H2 methodology for the cost-effective design of dependable systems.

Scalable allocation of safety integrity levels in automotive systems (2015)
Thesis
Azevedo, L. P. D. S. (2015). Scalable allocation of safety integrity levels in automotive systems. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4218322

The allocation of safety integrity requirements is an important problem in modern safety engineering. It is necessary to find an allocation that meets system level safety integrity targets and that is simultaneously cost-effective. As safety-critical... Read More about Scalable allocation of safety integrity levels in automotive systems.

Quantitative evaluation of Pandora Temporal Fault Trees via Petri Nets (2015)
Journal Article
Kabir, S., Papadopoulos, Y., & Walker, M. (2015). Quantitative evaluation of Pandora Temporal Fault Trees via Petri Nets. IFAC Proceedings Volumes/ International Federation of Automatic Control, 48(21), 458-463. https://doi.org/10.1016/j.ifacol.2015.09.569

© 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved. Using classical combinatorial fault trees, analysts are able to assess the effects of combinations of failures on system behaviour but are unab... Read More about Quantitative evaluation of Pandora Temporal Fault Trees via Petri Nets.

Automatic allocation of safety requirements to components of a software product line (2015)
Journal Article
De Oliveira, A. L., Papadopoulos, Y., Azevedo, L. S., Parker, D., Braga, R. T., Masiero, P. C., …Kelly, T. (2015). Automatic allocation of safety requirements to components of a software product line. IFAC Proceedings Volumes/ International Federation of Automatic Control, 48(21), 1309-1314. https://doi.org/10.1016/j.ifacol.2015.09.706

Safety critical systems developed as part of a product line must still comply with safety standards. Standards use the concept of Safety Integrity Levels (SILs) to drive the assignment of system safety requirements to components of a system under des... Read More about Automatic allocation of safety requirements to components of a software product line.

Automating allocation of development assurance levels: An extension to HiP-HOPS (2015)
Journal Article
Sorokos, I., Papadopoulos, Y., Azevedo, L., Parker, D., & Walker, M. (2015). Automating allocation of development assurance levels: An extension to HiP-HOPS. IFAC Proceedings Volumes/ International Federation of Automatic Control, 48(7), 9-14. https://doi.org/10.1016/j.ifacol.2015.06.466

Controlling the allocation of safety requirements across a system's architecture from the early stages of development is an aspiration embodied in numerous major safety standards. Manual approaches of applying this process in practice are ineffective... Read More about Automating allocation of development assurance levels: An extension to HiP-HOPS.

A synthesis of logic and biology in the design of dependable systems (2015)
Journal Article
Papadopoulos, Y. (2015). A synthesis of logic and biology in the design of dependable systems. IFAC Proceedings Volumes/ International Federation of Automatic Control, 28(7), 1-8. https://doi.org/10.1016/j.ifacol.2015.06.465

The technologies of model-based design and dependability analysis in the design of dependable systems, including software intensive systems, have advanced in recent years. Much of this development can be attributed to the application of advances in f... Read More about A synthesis of logic and biology in the design of dependable systems.

Supporting the automated generation of modular product line safety cases (2015)
Book Chapter
de Oliveira, A. L., Braga, R. T., Masiero, P. C., Papadopoulos, Y., Habli, I., & Kelly, T. (2015). Supporting the automated generation of modular product line safety cases. In W. Zamojski, J. Mazurkiewicz, J. Sugier, T. Walkowiak, & J. Kacprzyk (Eds.), . https://doi.org/10.1007/978-3-319-19216-1_30

Abstract The effective reuse of design assets in safety-critical Software Product Lines (SPL) would require the reuse of safety analyses of those assets in the variant contexts of certification of products derived from the SPL. This in turn requires... Read More about Supporting the automated generation of modular product line safety cases.

Model transformation for multi-objective architecture optimisation of dependable systems (2015)
Journal Article
Mian, Z., Bottaci, L., Papadopoulos, Y., Sharvia, S., & Mahmud, N. (2015). Model transformation for multi-objective architecture optimisation of dependable systems. Advances in Intelligent Systems and Computing, 307, 91-110. https://doi.org/10.1007/978-3-319-08964-5_6

The promise of model-based engineering is that by use of an integrated and coherent system model both functional and non-functional requirements may be analysed, implemented and tested in a rigorous and cost-effective manner. An important part of mod... Read More about Model transformation for multi-objective architecture optimisation of dependable systems.

Model-based dependability analysis : state-of-the-art, challenges and future outlook (2015)
Book Chapter
Sharvia, S., Kabir, S., Walker, M., & Papadopoulos, Y. (2015). Model-based dependability analysis : state-of-the-art, challenges and future outlook. In I. Mistrik, N. Ali, B. Tekinerdogan, R. Soley, & J. Grundy (Eds.), Software Quality Assurance: In Large Scale and Complex Software-intensive Systems (251-278). Elsevier. https://doi.org/10.1016/B978-0-12-802301-3.00012-0

Abstract: Over the past two decades, the study of model-based dependability analysis has gathered significant research interest. Different approaches have been developed to automate and address various limitations of classical dependability technique... Read More about Model-based dependability analysis : state-of-the-art, challenges and future outlook.

Reliability analysis of dynamic systems by translating temporal fault trees into Bayesian networks (2014)
Book Chapter
Kabir, S., Walker, M., & Papadopoulos, Y. (2014). Reliability analysis of dynamic systems by translating temporal fault trees into Bayesian networks. In Model-Based Safety and Assessment; Lecture Notes in Computer Science (96-109). Springer Verlag. https://doi.org/10.1007/978-3-319-12214-4_8

Classical combinatorial fault trees can be used to assess combinations of failures but are unable to capture sequences of faults, which are important in complex dynamic systems. A number of proposed techniques extend fault tree analysis for dynamic s... Read More about Reliability analysis of dynamic systems by translating temporal fault trees into Bayesian networks.

Integrating model checking with HiP-HOPS in model-based safety analysis (2014)
Journal Article
Sharvia, S., & Papadopoulos, Y. (2015). Integrating model checking with HiP-HOPS in model-based safety analysis. Reliability Engineering and System Safety, 135(March), 64-80. https://doi.org/10.1016/j.ress.2014.10.025

The ability to perform an effective and robust safety analysis on the design of modern safety–critical systems is crucial. Model-based safety analysis (MBSA) has been introduced in recent years to support the assessment of complex system design by fo... Read More about Integrating model checking with HiP-HOPS in model-based safety analysis.

An approach to safety analysis of clinical workflows (2014)
Journal Article
Al-Qora'n, L., Gordon, N., Sharvia, S., Walker, M., & Papadopoulos, Y. (2014). An approach to safety analysis of clinical workflows. Athens Journal of Health, 1(3), 201-216. https://doi.org/10.30958/ajh.1-3-4

A clinical workflow considers the information and processes that are involved in providing a clinical service. They are safety critical since even minor faults have the potential to propagate and consequently cause harm to a patient, or even for a pa... Read More about An approach to safety analysis of clinical workflows.

Enhancing the EAST-ADL error model with HiP-HOPS semantics (2014)
Journal Article
Sharvia, S., Papadopoulos, Y., Chen, D., Walker, M., Yuan, W., & Lönn, H. (2014). Enhancing the EAST-ADL error model with HiP-HOPS semantics. Athens journal of technology & engineering, 1(2), 119-136

EAST-ADL is a domain-specific modelling language for the engineering of automotive embedded systems. The language has abstractions that enable engineers to capture a variety of information about design in the course of the lifecycle — from requiremen... Read More about Enhancing the EAST-ADL error model with HiP-HOPS semantics.

Exploring the impact of different cost heuristics in the allocation of safety integrity levels (2014)
Journal Article
Azevedo, L. S., Parker, D., Papadopoulos, Y., Walker, M., Sorokos, I., & Araújo, R. E. (2014). Exploring the impact of different cost heuristics in the allocation of safety integrity levels. Lecture notes in computer science, 8822, 70-81. https://doi.org/10.1007/978-3-319-12214-4_6

Contemporary safety standards prescribe processes in which system safety requirements, captured early and expressed in the form of Safety Integrity Levels (SILs), are iteratively allocated to architectural elements. Different SILs reflect different r... Read More about Exploring the impact of different cost heuristics in the allocation of safety integrity levels.

Using simulation to evaluate dynamic systems with weibull or lognormal distributions (2014)
Journal Article
Edifor, E., Gordon, N., Walker, M., & Papadopoulos, Y. (2014). Using simulation to evaluate dynamic systems with weibull or lognormal distributions. Advances in Intelligent Systems and Computing, 286, 117-187. https://doi.org/10.1007/978-3-319-07013-1_17

© 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.

Automatic optimisation of system architectures using EAST-ADL (2013)
Journal Article
Walker, M., Reiser, M., Tucci-Piergiovanni, S., Papadopoulos, Y., Lönn, H., Mraidha, C., …Servat, D. (2013). Automatic optimisation of system architectures using EAST-ADL. Journal of Systems and Software, 86(10), 2467-2487. https://doi.org/10.1016/j.jss.2013.04.001

There are many challenges which face designers of complex system architectures, particularly safety-critical or real-time systems. The introduction of Architecture Description Languages (ADLs) has helped to meet these challenges by consolidating info... Read More about Automatic optimisation of system architectures using EAST-ADL.

Assisted assignment of automotive safety requirements (2013)
Journal Article
Azevedo, L. D. S., Parker, D., Walker, M., Papadopoulos, Y., & Araújo, R. E. (2014). Assisted assignment of automotive safety requirements. IEEE Software, 31(1), 62-68. https://doi.org/10.1109/ms.2013.118

ISO 26262, a functional-safety standard, uses Automotive Safety Integrity Levels (ASILs) to assign safety requirements to automotive-system elements. System designers initially assign ASILs to system-level hazards and then allocate them to elements o... Read More about Assisted assignment of automotive safety requirements.

Safety Analysis of a Remote Patient Monitoring System with a Guideline Based Decision Support (2013)
Book Chapter
Al-Qora'n, L., Sharvia, S., Papadopoulos, Y., & Gordon, N. (2013). Safety Analysis of a Remote Patient Monitoring System with a Guideline Based Decision Support. Global Telemedicine and eHealth Updates: Knowledge Resources (527 - 531). International Society for Telemedicine & eHealth

Home Telehealth systems are used to help in the management of chronic conditions by patients themselves. Effective safety analysis tools are needed to ensure reliability and safety of these high risk systems. We hereby explain how Hierarchically-Perf... Read More about Safety Analysis of a Remote Patient Monitoring System with a Guideline Based Decision Support.

Dynamic model-based safety analysis: from state machines to temporal fault trees (2012)
Thesis
Mahmud, N. (2012). Dynamic model-based safety analysis: from state machines to temporal fault trees. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4214015

Finite state transition models such as State Machines (SMs) have become a prevalent paradigm for the description of dynamic systems. Such models are well-suited to modelling the behaviour of complex systems, including in conditions of failure, and wh... Read More about Dynamic model-based safety analysis: from state machines to temporal fault trees.

CernoCAMAL : a probabilistic computational cognitive architecture (2012)
Thesis
Miri, H. (2012). CernoCAMAL : a probabilistic computational cognitive architecture. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4214117

This thesis presents one possible way to develop a computational cognitive architecture, dubbed CernoCAMAL, that can be used to govern artificial minds probabilistically. The primary aim of the CernoCAMAL research project is to investigate how its pr... Read More about CernoCAMAL : a probabilistic computational cognitive architecture.

System dependability modelling and analysis using AADL and HiP-HOPS (2012)
Journal Article
Mian, Z., Bottaci, L., Papadopoulos, Y., & Biehl, M. (2012). System dependability modelling and analysis using AADL and HiP-HOPS. IFAC Proceedings Volumes/ International Federation of Automatic Control, 45(6), 1647-1652. https://doi.org/10.3182/20120523-3-RO-2023.00334

The Architecture Analysis and Design Language (AADL) is gaining widespread acceptance in aerospace, automobile and avionics industries for designing dependability-critical systems. The design process of dependable systems must address both cost and d... Read More about System dependability modelling and analysis using AADL and HiP-HOPS.

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.

Multi-objective system optimisation with respect to availability, maintainability and cost (2012)
Thesis
Nggada, S. H. (2012). Multi-objective system optimisation with respect to availability, maintainability and cost. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4213593

Safety critical engineering systems are becoming increasingly larger and more complex. One way of ensuring the dependability of such systems is via architectural redundancy and replication of components. Use of redundancy has its limitations though,... Read More about Multi-objective system optimisation with respect to availability, maintainability and cost.

Integrated application of compositional and behavioural safety analysis (2011)
Book Chapter
Sharvia, S., & Papadopoulos, Y. (2011). Integrated application of compositional and behavioural safety analysis. In W. Zamojski, J. Kacprzyk, J. Mazurkiewicz, J. Sugier, & T. Walkowiak (Eds.), Dependable Computer Systems (179-192). Berlin: Springer. https://doi.org/10.1007/978-3-642-21393-9_14

The design complexity of modern safety critical systems presents various challenges for its safety assessment process. In recent years, Model-Based Safety Analysis (MBSA) has been proposed to achieve more-robust and effective safety assessment techni... Read More about Integrated application of compositional and behavioural safety analysis.

Integrated safety and architecture modeling for automotive embedded systems (2011)
Journal Article
Chen, D., Johansson, R., Lönn, H., Blom, H., Walker, M., Papadopoulos, Y., …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.

Integrated application of compositional and behavioural safety analysis (2011)
Thesis
Sharvia, S. (2011). Integrated application of compositional and behavioural safety analysis. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4211046

To address challenges arising in the safety assessment of critical engineering systems, research has recently focused on automating the synthesis of predictive models of system failure from design representations. In one approach, known as compositio... Read More about Integrated application of compositional and behavioural safety analysis.

An approach to optimization of fault tolerant architectures using HiP-HOPS (2011)
Journal Article
Adachi, M., Papadopoulos, Y., Sharvia, S., Parker, D., & Tohdo, T. (2011). An approach to optimization of fault tolerant architectures using HiP-HOPS. Software: Practice and Experience, 41(11), 1303-1327. https://doi.org/10.1002/spe.1044

New processes for the design of dependable systems must address both cost and dependability concerns. They should also maximize the potential for automation to address the problem of increasing technological complexity and the potentially immense des... Read More about An approach to optimization of fault tolerant architectures using HiP-HOPS.

A hierarchical method for the reduction of temporal expressions in Pandora (2010)
Conference Proceeding
Papadopoulos, Y., & Walker, M. (2010). A hierarchical method for the reduction of temporal expressions in Pandora. . https://doi.org/10.1145/1772630.1772634

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)
Conference Proceeding
Papadopoulos, Y., Walker, M., Reiser, M., Weber, M., Chen, D., Törngren, M., …Sandberg, A. (2010). Automatic allocation of safety integrity levels. . https://doi.org/10.1145/1772643.1772646

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.

Dynamic effect of perfect preventive maintenance on system reliability and cost using HiP-HOPS (2010)
Journal Article
Nggada, S. H., Parker, D. J., & Papadopoulos, Y. I. (2010). Dynamic effect of perfect preventive maintenance on system reliability and cost using HiP-HOPS. IFAC Proceedings Volumes/ International Federation of Automatic Control, 43(17), 204-209. https://doi.org/10.3182/20100908-3-pt-3007.00039

The occurrence of failure in a safety critical engineering system can be reduced through the use of preventive maintenance (PM). Each time a component of the system is maintained its effective age is reduced; the extent of this age reduction depends... Read More about Dynamic effect of perfect preventive maintenance on system reliability and cost using HiP-HOPS.

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., …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)
Conference Proceeding
Papadopoulos, Y., Mahmud, N., & Walker, M. (2010). A translation of state machines to temporal fault trees. . https://doi.org/10.1109/dsnw.2010.5542620

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.

Specification and use of component failure patterns (2010)
Thesis
Wolforth, I. P. (2010). Specification and use of component failure patterns. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4211022

Safety-critical systems are typically assessed for their adherence to specified safety properties. They are studied down to the component-level to identify root causes of any hazardous failures. Most recent work with model-based safety analysis has f... Read More about Specification and use of component failure patterns.

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.

Multi-objective optimisation of safety-critical hierarchical systems (2010)
Thesis
Parker, D. (. J. (2010). Multi-objective optimisation of safety-critical hierarchical systems. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4209821

Achieving high reliability, particularly in safety critical systems, is an important and often mandatory requirement. At the same time costs should be kept as low as possible. Finding an optimum balance between maximising a system's reliability and m... Read More about Multi-objective optimisation of safety-critical hierarchical systems.

Extending HiP-HOPS with Capabilities of Planning Preventative Maintenance (2010)
Book Chapter
Parker, D., & Papadopoulos, Y. (2010). Extending HiP-HOPS with Capabilities of Planning Preventative Maintenance. In M. Sarrafzadeh, & P. Petratos (Eds.), Strategic Advantage of Computing Information Systems in Enterprise Management (231 - 245). ATINER

An effective preventive maintenance (PM) policy for components of an engineering system slows down the rate at which component fatigue accumulates, thereby minimising the occurrence of component failure. The benefit of PM at system level is improveme... Read More about Extending HiP-HOPS with Capabilities of Planning Preventative Maintenance.

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.

Pandora : a logic for the qualitative analysis of temporal fault trees (2009)
Thesis
Walker, M. (. D. (2009). Pandora : a logic for the qualitative analysis of temporal fault trees. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4209344

Fault Tree Analysis (FTA) is a valuable systems analysis technique widely used in safety analysis and reliability engineering, but it is not without its faults; in particular, it struggles to analyse systems in which time plays an important role, bec... Read More about Pandora : a logic for the qualitative analysis of temporal fault trees.

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., …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.

Semi automatic failure analysis based on simulation models (2008)
Conference Proceeding
Hamann, R., Uhlig, A., Papadopoulos, Y., Rüde, E., Grätz, U., Walker, M., & Lien, R. (2008). Semi automatic failure analysis based on simulation models. . https://doi.org/10.1115/omae2008-57256

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.

Multi-objective optimization of dependability attributes using an asynchronous heterogeneous hierarchical parallel genetic algorithm (2008)
Journal Article
Wenhua, Z., Papadopoulos, Y., & Parker, D. (2008). Multi-objective optimization of dependability attributes using an asynchronous heterogeneous hierarchical parallel genetic algorithm. IFAC Proceedings Volumes/ International Federation of Automatic Control, 41(3), 199-204. https://doi.org/10.3182/20081205-2-cl-4009.00036

The optimal satisfaction of dependability attributes and cost, in the design of engineering systems, is a hard multi-objective optimization problem which requires automated algorithms that can effectively search large design spaces. In this paper, a... Read More about Multi-objective optimization of dependability attributes using an asynchronous heterogeneous hierarchical parallel genetic algorithm.

A language for failure patterns and application in safety analysis (2008)
Conference Proceeding
Wolforth, I., Walker, M., & Papadopoulos, Y. (2008). A language for failure patterns and application in safety analysis. . https://doi.org/10.1109/depcos-relcomex.2008.44

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.

Non-coherent modelling in compositional fault tree analysis (2008)
Journal Article
Sharvia, S., & Papadopoulos, Y. I. (2008). Non-coherent modelling in compositional fault tree analysis. IFAC Proceedings Volumes/ International Federation of Automatic Control, 41(2), 4138-4143. https://doi.org/10.3182/20080706-5-KR-1001.00696

The inclusion of NOT gates in a fault tree creates a 'non-coherent' structure in which not only the failure of a component but also the negation of failure, i.e. the working state of the component, can contribute to the undesirable effects on a syste... Read More about Non-coherent modelling in compositional fault tree analysis.

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.