6 research outputs found
Dépliage de Boucles Versus Précision Numérique
Les calculs en nombres flottants sont intensivement utilisés dans divers domaines, notamment les
systÚmes embarqués critiques. En général, les résultats de ces calculs sont perturbés par les erreurs
dâarrondi. Dans un scenario critique, ces erreurs peuvent ĂȘtre accumulĂ©es et propagĂ©es, gĂ©nĂ©rant ainsi
des dommages plus ou moins graves sur le plan humain, matériel, financier, etc. Il est donc souhaitable
dâobtenir les rĂ©sultats les plus prĂ©cis possibles lorsque nous utilisons lâarithmĂ©tique flottante.
Pour remĂ©dier Ă ce problĂšme, lâoutil Salsa [7] permet dâamĂ©liorer la prĂ©cision des calculs en corrigeant
partiellement ces erreurs dâarrondi par une transformation automatique et source Ă source des
programmes. La principale contribution de ce travail consiste Ă analyser, Ă Ă©tudier si lâoptimisation
par dépliage de boucles améliore plus la précision numérique des calculs dans le programme initial.
Ă cours terme, on souhaite dĂ©finir un facteur de dĂ©pliage de boucles, câest Ă dire, trouver quand est-ce
quâil est pertinent de dĂ©plier la boucle dans le programme
MUPPAAL:Reducing and Removing Equivalent and Duplicate Mutants in UPPAAL
peer reviewedMutation Testing (MT) is a test quality assessment technique that creates mutants by injecting artificial faults into the system and evaluating the ability of tests to distinguish these mutants. We focus on MT for safety-critical Timed Automata (TA). MT is prone to equivalent and duplicate mutants, the former having the same behaviour as the original system and the latter other mutants. Such mutants bring no value and induce useless test case executions. We propose MUPPAAL, a tool that: (1) offers a new operator reducing the occurrence of mutant duplicates; (2) an efficient bisimulation algorithm removing remaining duplicates; (3) leverages existing equivalence-avoiding mutation operators. Our experiments on four UPPAAL case studies indicate that duplicates represent up to 32% of all mutants and that the MUPPAAL bisimulation algorithm can identify them more than 99% of the time
Authoring and automatic verification of interactive multimedia scores
International audienceThe advances in authoring of interactive scores call for a thorough analysis of the written scores. A possible way to ensure correctness of an interactive score is through the use of formal techniques such as model checking. In this work, we present a visual model of the inter-media sequencer i-score and we propose a Timed Automata encoding to reason about the interactive scores written in this software. The verification of some properties of interactive scores is presented, along an evaluation of the performance of the model-checking process with uppaal
Simulation combined model-based testing method for train control systems
A Train Control System (TCS) is utilised to guard the operational safety of the trains in railway systems. Therefore, functional testing is applied to verify consistency between the TCS and specification requirements. Traditional functional testing in TCSs is mainly based on manually designed test cases, which is becoming unsuitable for testing increasingly complex TCSs. Therefore, Model-Based Testing (MBT) methods have been introduced into TCS functional testing, to improve the efficiency and coverage of TCS testing, with application difficulties. To overcome the difficulties of applying MBT methods to test TCSs, the author introduces simulation combined MBT which combines an MBT method with simulation. Modelling method and implementation method for the proposed approach were explained in detail. Two case studies were undertaken to explore the effectiveness of the testing platform developed. The testing results obtained prove that the testing platform can be utilised to implement the functional testing of TCSs. To prove that the MBT platform is effective in detecting errors in the SUT, validation and verification was undertaken, which include validation of specification requirements and verification of the MBT platform. The testing performance is proven to be better than existing MBT methods in terms of coverage and efficiency