Leveraging Applications of Formal Methods, Verification and Validation: Tools and Trends [electronic resource] : 9th International Symposium on Leveraging Applications of Formal Methods, ISoLA 2020, Rhodes, Greece, October 20–30, 2020, Proceedings, Part IV /

From Verification to Explanation (Track Introduction) -- An Algorithm to Compute a Strict Partial Ordering of Actions in Action Traces -- TraceVis: Towards Visualization for Deep Statistical Model Checking -- Engineering of Digital Twins for Cyber-Physical Systems -- Understanding Digital Twins for Cyber-Physical Systems: A Conceptual Model -- Uncertainty quantification and runtime monitoring using environment-aware digital twins -- Designing Distributed Control with Hybrid Active Objects -- Towards a Digital Twin - Modelling an Agricultural Vehicle -- Digital Modelling in the Railways -- Engineering a Digital Twin for Manual Assembling -- Towards Digital Twins for Knowledge-driven Construction Progress and Predictive Safety Analysis on a Construction Site -- Software Verification Tools (Track Introduction) -- Benchmarking Open-Source Static Analyzers for Security Testing for C -- Verification of Liveness and Safety in BP using BPjs -- On Correctness, Precision, and Performance in Quantitative Verification -- Every Component Matters: Generating Parallel Verification Benchmarks with Hardness Guarantees.

The four-volume set LNCS 12476 - 12479 constitutes the refereed proceedings of the 9th International Symposium on Leveraging Applications of Formal Methods, ISoLA 2020, which was planned to take place during October 20–30, 2020, on Rhodes, Greece. The event itself was postponed to 2021 due to the COVID-19 pandemic. The papers presented were carefully reviewed and selected for inclusion in the proceedings. Each volume focusses on an individual topic with topical section headings within the volume: Part I, Verification Principles: Modularity and (De-)Composition in Verification; X-by-Construction: Correctness meets Probability; 30 Years of Statistical Model Checking; Verification and Validation of Concurrent and Distributed Systems. Part II, Engineering Principles: Automating Software Re-Engineering; Rigorous Engineering of Collective Adaptive Systems. Part III, Applications: Reliable Smart Contracts:State-of-the-art, Applications, Challenges and Future Directions; Automated Verification of Embedded Control Software; Formal methods for DIStributed COmputing in future RAILway systems. Part IV, Tools and Trends: From Verification to Explanation; Engineering of Digital Twins for Cyber-Physical Systems; Software Verification Tools.