Proceedings of SUMo and CompoNet 2011

International audienc

Computing Bounds for Counter Automata

Qualitative formal verification, that seeks Boolean answers about the behavior of a system, is often insufficient for practical purposes. Observing quantitative information is of greater interest, e.g. for the calibration of a battery or a real-time scheduler. Historically, the focus has been on quantities in continuous domain, but recent years showed a renewed interest for discrete quantitative domains. Counter Automata (CA) is a quantitative extension of classical omega-automata. Recently a nice theory has been developed for them that extends the qualitative setting, with counterparts in terms of logics, automata and algebraic structure. We propose an adaptation, with plenty of practical applications,  of this formalism to express properties over discrete quantitative domains. The behavior of a Counter Automaton defines a function from infinite words to integers. Finding the bounds of such a function over a given set of words can be seen as an extension of qualitative universal and existential model-checking. Although the problem of determining whether such bounds are finite have already been addressed, efficient algorithms to compute their exact values still lack. We propose an non-naive method for the computation of the exact values of these bounds. It relies on a generalization of the emptiness problem of omega-automata. To solve this generalized emptiness problem, we propose an algorithm that extends emptiness check algorithms based on SCC enumeration.

From Formal Specifications to Ready-to-Use Software Components: The Concurrent Object-Oriented Petri Net Approach

CO-OPN (Concurrent Object Oriented Petri Net) is a formal specification language for modelling distributed systems; it is based on coordinated algebraic Petri nets. In this paper we describe a method for generating an executable prototype from a CO-OPN specification. We focus our discussion on the generation of executable code for CO-OPN classes. CO-OPN classes are defined using Petri Nets. The main problems arise when implementing synchronization and non-determinism of CO-OPN classes in procedural languages. Our method proposes a solution to these problems. Another interesting aspect of our method is the easy integration of a generated prototype into any existing system. This paper focuses on the generation of Java code that fulfils the Java Beans component architecture, however our approach is also applicable to other object-oriented implementation languages with a component architecture

From an Abstract Object-Oriented Model to a Ready-to-Use Embedded System Controller

We present an example of a construction of an embedded software system-a controller-from the formal specification to executable code. The CO-OPN (Concurrent Object Oriented Petri Net) formal specification language is used for modelling the controller and the associated hardware system with the inherent limitation of its physical components. CO-OPN formal language is based on coordinated algebraic Petri nets. The CO-OPN model can be used to verify some properties of the controller in the concrete physical environment. This is achieved by constrained animation of the valid prototype produced by automatic code generation. The possibility to incrementally refine the generated code can be used to obtain a more efficient implementation

TREXMO: a translation tool to support the use of regulatory occupational exposure models

Occupational exposure models vary significantly in their complexity, purpose, and the level of expertise required from the user. Different parameters in the same model may lead to different exposure estimates for the same exposure situation. This paper presents a tool developed to deal with this concern-TREXMO or TRanslation of EXposure MOdels. TREXMO integrates six commonly used occupational exposure models, namely, ART v.1.5, STOFFENMANAGER(®) v.5.1, ECETOC TRA v.3, MEASE v.1.02.01, EMKG-EXPO-TOOL, and EASE v.2.0. By enabling a semi-automatic translation between the parameters of these six models, TREXMO facilitates their simultaneous use. For a given exposure situation, defined by a set of parameters in one of the models, TREXMO provides the user with the most appropriate parameters to use in the other exposure models. Results showed that, once an exposure situation and parameters were set in ART, TREXMO reduced the number of possible outcomes in the other models by 1-4 orders of magnitude. The tool should manage to reduce the uncertain entry or selection of parameters in the six models, improve between-user reliability, and reduce the time required for running several models for a given exposure situation. In addition to these advantages, registrants of chemicals and authorities should benefit from more reliable exposure estimates for the risk characterization of dangerous chemicals under Regulation, Evaluation, Authorisation and restriction of CHemicals (REACH)

Modelling a Secure, Mobile, and Transactional System with CO-OPN

Modelling complex concurrent systems is often difficult and error-prone, in particular when new concepts coming from advanced practical applications are considered. These new application domains include dynamicity, mobility, security, and localization dependent computing. In order to fully model and prototype such systems we propose to use several concepts introduced in our specification language CO-OPN, like context, dynamicity, mobility, subtyping and inheritance. CO-OPN (Concurrent Object Oriented Petri Net) is a formal specification language for modelling distributed systems; it is based on coordinated algebraic Petri nets. This paper focuses on the use of several basic mechanisms of CO-OPN for modelling mobile systems and the generation of corresponding Java code. A significant example of distributors accessible through mobile devices (for example, PDA with Bluetooth) is fully modelled and implemented with our technique