This book constitutes the refereed proceedings of the 5th International Workshop on Formal Techniques for Safety-Critical Systems, FTSCS 2016, held in Tokyo, Japan, in November 2016. The 9 revised full papers presented together with an abstract of an invited talk were carefully reviewed and selected from 23 submissions. The papers are organized in topical sections on specification and verification; automotive and railway systems; circuits and cyber-physical systems; parametrized verification.

This book constitutes the refereed proceedings of the 7th International Workshop on Formal Techniques for Safety-Critical Systems, FTSCS 2019, held in Shenzhen, China, in November 2019. The 6 revised full papers presented were carefully reviewed and selected from 17 submissions. Additionally, the volume presents 1 invited paper, 1 tool paper, and 1 work in progrerss. The papers are focused on the topics of the use of formal methods for analyzing safety-critical systems; methods, techniques and tools to support automated analysis, certication, debugging, etc., of complex safety/QoS-critical systems; analysis methods that address the limitations of formal methods in industry (usability, scalability, etc.); formal analysis support for modeling languages used in industry; code generation from validated models.

0 e This is the proceedings of the first annual symposium of the Safety-critical Systems Club (The Watershed Media Centre, Bristol, 9-11 February 1993), which provided a forum for exploring and discussing ways of achieving safety in computer systems to be used in safety-critical industrial applications. The book is divided into three parts, which correspond with the themes of the three days of the symposium. The first - Experience from Around Europe - brings together information on developments in safety-critical systems outside the UK. The second - Current Research - consists of papers on large projects within the UK, which involve collaboration between academia and industry, providing techniques and methods to enhance safety. The final part - Achieving and Evaluating Safety - explores how methods already in use in other domains may be applied to safety, and examines the relationships between safety and other attributes such as quality and security. The papers identify the current problems and issues of interest in the field of safety-critical software-based systems, and provide valuable up-to-date material for those in both academia and industry. The academic will benefit from information about current research complimentary to his own, and the industrialist will learn of the technologies which will soon be available and where to find them.

This book constitutes the proceedings of the 24th International Conference on Formal Methods for Industrial Critical Systems, FMICS 2019, held in Amsterdam, The Netherlands, in August 2019. The 9 regular papers presented in this volume were carefully reviewed and selected from 15 submissions. The conference also featured invited talks by Jaco van de Pol (Aarhus University, and Twente University), jointly with CONCUR, and Holger Hermanns (Universität des Saarlandes) and a special session on (commercial) formal methods in industry. The aim of the FMICS conference series is to provide a forum for researchers who are interested in the development and application of formal methods in industry. In particular, FMICS brings together scientists and engineers who are active in the area of formal methods and interested in exchanging their experiences in the industrial usage of these methods. The FMICS conference series also strives to promote research and development for the improvement of formal methods and tools for industrial applications.

This book constitutes the proceedings of the 16th International Workshop on Formal Methods for Industrial Critical Systems, FMICS 2011, held in Trento, Italy, in August 2011. The 16 papers presented together with 2 invited talks were carefully reviewed and selected from 39 submissions. The aim of the FMICS workshop series is to provide a forum for researchers who are interested in the development and application of formal methods in industry. It also strives to promote research and development for the improvement of formal methods and tools for industrial applications.

In the presence of data and computational resources, machine learning can be used to synthesize software automatically. For example, machines are now capable of learning complicated pattern recognition tasks and sophisticated decision policies, two key capabilities in autonomous cyber-physical systems. Unfortunately, humans find software synthesized by machine learning algorithms difficult to interpret, which currently limits their use in safety-critical applications such as medical diagnosis and avionic systems. In particular, successful deployments of safety-critical systems mandate the execution of rigorous verification activities, which often rely on human insights, e.g., to identify scenarios in which the system shall be tested. A natural pathway towards a viable verification strategy for such systems is to leverage formal verification techniques, which, in the presence of a formal specification, can provide definitive guarantees with little human intervention. However, formal verification suffers from scalability issues with respect to system complexity. In this thesis, we investigate the limits of current formal verification techniques when applied to a class of machine learning models called tree ensembles, and identify model-specific characteristics that can be exploited to improve the performance of verification algorithms when applied specifically to tree ensembles. To this end, we develop two formal verification techniques specifically for tree ensembles, one fast and conservative technique, and one exact but more computationally demanding. We then combine these two techniques into an abstraction-refinement approach, that we implement in a tool called VoTE (Verifier of Tree Ensembles). Using a couple of case studies, we recognize that sets of inputs that lead to the same system behavior can be captured precisely as hyperrectangles, which enables tractable enumeration of input-output mappings when the input dimension is low. Tree ensembles with a high-dimensional input domain, however, seems generally difficult to verify. In some cases though, conservative approximations of input-output mappings can greatly improve performance. This is demonstrated in a digit recognition case study, where we assess the robustness of classifiers when confronted with additive noise.

"I highly recommend Mr. Hobbs' book." - Stephen Thomas, PE, Founder and Editor of FunctionalSafetyEngineer.com Safety-critical devices, whether medical, automotive, or industrial, are increasingly dependent on the correct operation of sophisticated software. Many standards have appeared in the last decade on how such systems should be designed and built. Developers, who previously only had to know how to program devices for their industry, must now understand remarkably esoteric development practices and be prepared to justify their work to external auditors. Embedded Software Development for Safety-Critical Systems discusses the development of safety-critical systems under the following standards: IEC 61508; ISO 26262; EN 50128; and IEC 62304. It details the advantages and disadvantages of many architectural and design practices recommended in the standards, ranging from replication and diversification, through anomaly detection to the so-called "safety bag" systems. Reviewing the use of open-source components in safety-critical systems, this book has evolved from a course text used by QNX Software Systems for a training module on building embedded software for safety-critical devices, including medical devices, railway systems, industrial systems, and driver assistance devices in cars. Although the book describes open-source tools for the most part, it also provides enough information for you to seek out commercial vendors if that’s the route you decide to pursue. All of the techniques described in this book may be further explored through hundreds of learned articles. In order to provide you with a way in, the author supplies references he has found helpful as a working software developer. Most of these references are available to download for free.

Safety-critical systems, by definition those systems whose failure can cause catastrophic results for people, the environment, and the economy, are becoming increasingly complex both in their functionality and their interactions with the environment. Unfortunately, safety assessments are still largely done manually, a time-consuming and error-prone

Defining a new development life-cycle methodology, together with a set of associated techniques and tools to develop highly critical systems using formal techniques, this book adopts a rigorous safety assessment approach explored via several layers (from requirements analysis to automatic source code generation). This is assessed and evaluated via a standard case study: the cardiac pacemaker. Additionally a formalisation of an Electrocardiogram (ECG) is used to identify anomalies in order to improve existing medical protocols. This allows the key issue - that formal methods are not currently integrated into established critical systems development processes - to be discussed in a highly effective and informative way. Using Event-B for Critical Device Software Systems serves as a valuable resource for researchers and students of formal methods. The assessment of critical systems development is applicable to all industries, but engineers and physicians from the health domain will find the cardiac pacemaker case study of particular value.

"This book explores different applications in V & V that spawn many areas of software development -including real time applications- where V & V techniques are required, providing in all cases examples of the applications"--Provided by publisher.