Régine Laleau

Steve Jeffrey Tueno Fotso, Marc Frappier, Amel Mammar et al.

In this paper, we use a combination of the SysML/KAOS requirements engineering method, an extension of SysML, with concepts of the KAOS goal model, and of the B System formal method. Translation rules from a SysML/KAOS goal model to a B System specification have been defined. They allow to obtain a skeleton of the B System specification. To complete it, we have defined a language to express the domain model associated to the goal model. The translation of this domain model gives the structural part of the B System specification. The contribution of this paper is the description of translation rules from SysML/KAOS domain models to B System specifications. We also present the formal verification of these rules and we describe an open source tool that implements the languages and the rules. Finally, we provide a review of the application of the SysML/KAOS method on case studies such as for the formal specification of the hybrid ERTMS/ETCS level 3 standard.

Steve Jeffrey Tueno Fotso, Marc Frappier, Régine Laleau et al.

This paper is related to the generalised/generic version of the SysML/KAOS domain metamodel and on translation and back propagation rules between the new domain models and B System specifications.

Régine Laleau, Dominique Méry, Shin Nakajima et al.

This volume contains the joint proceedings of IMPEX 2017, the first workshop on Handling IMPlicit and EXplicit knowledge in formal system development and FM&MDD, the second workshop on Formal and Model-Driven Techniques for Developing Trustworthy Systems (FM&MDD) held together on November 16, 2017 in Xi'an, China, as part of ICFEM 2017, 19th International Conference on Formal Engineering Methods. IMPEX emphasises mechanisms for reducing heterogeneity of models induced by the absence of explicit semantics expression in the formal techniques used to specify these models. More precisely, the meeting targets to highlight the advances in handling both implicit and explicit semantics in formal system developments. The aims of FM&MDD are to advance the understanding in the area of developing and applying formal and model-driven techniques for designing trustworthy systems, to discuss the emerging issues in the area, to improve the dialog between different research communities and between academia and industry, to discuss a roadmap of the future research in the area and to create a forum for discussing and disseminating the new ideas and the research results in the area

Steve Tueno, Régine Laleau, Amel Mammar et al.

Nowadays, the usefulness of a formal language for ensuring the consistency of requirements is well established. The work presented here is part of the definition of a formally-grounded, model-based requirements engineering method for critical and complex systems. Requirements are captured through the SysML/KAOS method and the targeted formal specification is written using the Event-B method. Firstly, an Event-B skeleton is produced from the goal hierarchy provided by the SysML/KAOS goal model. This skeleton is then completed in a second step by the Event-B specification obtained from system application domain properties that gives rise to the system structure. Considering that the domain is represented using ontologies through the SysML/KAOS Domain Model method, is it possible to automatically produce the structural part of system Event-B models ? This paper proposes a set of generic rules that translate SysML/KAOS domain ontologies into an Event-B specification. The rules have been expressed, verified and validated through the Rodin tool using the Event-B method. They are illustrated through a case study dealing with a landing gear system. Our proposition makes it possible to automatically obtain, from a representation of the system application domain in the form of ontologies, the structural part of the Event-B specification which will be used to formally validate the consistency of system requirements.

Steve Tueno, Régine Laleau, Amel Mammar et al.

A means of building safe critical systems consists of formally modeling the requirements formulated by stakeholders and ensuring their consistency with respect to application domain properties. This paper proposes a metamodel for an ontology modeling formalism based on OWL and PLIB. This modeling formalism is part of a method for modeling the domain of systems whose requirements are captured through SysML/KAOS. The formal semantics of SysML/KAOS goals are represented using Event-B specifications. Goals provide the set of events, while domain models will provide the structure of the system state of the Event-B specification. Our proposal is illustrated through a case study dealing with a Cycab localization component specification. The case study deals with the specification of a localization software component that uses GPS,Wi-Fi and sensor technologies for the realtime localization of the Cycab vehicle, an autonomous ground transportation system designed to be robust and completely independent.

Thomas Fayolle, Marc Frappier, Régine Laleau et al.

In a traditional formal development process, e.g. using the B method, the informal user requirements are (manually) translated into a global abstract formal specification. This translation is especially difficult to achieve. The Event-B method was developed to incrementally and formally construct such a specification using stepwise refinement. Each increment takes into account new properties and system aspects. In this paper, we propose to couple a graphical notation called Algebraic State-Transition Diagrams (ASTD) with an Event-B specification in order to provide a better understanding of the software behaviour. The dynamic behaviour is captured by the ASTD, which is based on automata and process algebra operators, while the data model is described by means of an Event-B specification. We propose a methodology to incrementally refine such specification couplings, taking into account new refinement relations and consistency conditions between the control specification and the data specification. We compare the specifications obtained using each approach for readability and proof complexity. The advantages and drawbacks of the traditional approach and of our methodology are discussed. The whole process is illustrated by a railway CBTC-like case study. Our approach is supported by tools for translating ASTD's into B and Event-B into B.