Timed Functional Modeling for Mixed-Signal Boards in Maintenance Testing

International audienceIn the context of maintenance testing and diagnosis of faulty boards, a functional FSM (Finite State Machine)- based model for mixed-signal boards has been introduced in a precedent paper. It has been extended for dealing with time sequences aspects. In this paper, the new modeling technique is presented

Timed Functional Modeling for Mixed-Signal Boards in Maintenance Testing: A Case Study

In the context of maintenance testing and diagnosis of faulty boards, a functional FSM (Finite State Machine)- based model for mixed-signal boards has been introduced in a precedent paper. It has been extended for dealing with time sequences aspects. In this paper, the new modeling technique is presented

Towards a New Modelling of Mixed-Signal Boards For Maintenance Testing

International audienceWe are introducing a new method for the test of mixed signal boards. The emphasis is on the functional modelling and test vectors generation. A prototype implementation of the method has been used and validated in an industrial case study

Maintenance Testing of Mixed-Signal Boards

In the context of maintenance and diagnosis of faulty boards, we introduce a functional FSM-based model for mixed-signal circuits. We target effi cient test sequences generation for ATE based on a high-level, functional modeling of components assemblies. The approach is flexible, allows to handle digital as well as analog and mixed-signal components in a similar way. A primary prototype has been developped, and two industrial cases partially processed

Maintenance Testing of Mixed-Signal Boards: the FCB case study

We present an ongoing work in the domain of mixed-signal board maintenance testing, supported by an industrial case study. We propose a method providing a semi-automation and an help for the board maintenance testing and diagnosis stages. It is validated by the implementation of a prototype tool

Combined Security and Schedulability Analysis for MILS Real-Time Critical Architectures

Real-time critical systems have to comply with stringent timing constraints, otherwise, disastrous consequences can occur at runtime. A large effort has been made to propose models and tools to verify timing constraints by schedulability analysis at the early stages of system designs. Fewer efforts have been made on verifying the security properties in these systems despite the fact that sinister consequences can also happen if these properties are compromised. In this article, we investigate how to jointly verify security and timing constraints. We show how to model a security architecture (MILS) and how to verify both timing constraints and security properties. Schedulability is investigated by the mean of scheduling analysis methods implemented into the Cheddar scheduling analyzer. Experiments are conducted to show the impact that improving security has on the schedulability analysis

New detection criteria and shunting monitoring in railway track circuit receivers

IWSHM-RS 2018, 2nd International Workshop on Structural Health Monitoring for Railway Systems, Qingdao, CHINE, 17-/10/2018 - 19/10/2018Track circuits play a major role in railway signaling. In some exceptional conditions, poor rail/wheel contact conditions may lead to a non-detection of the train on the zone. A presentation of the principle of detection by track circuits is proposed to introduce the existing detection criterion. The aim of the paper is first to present new detection approaches based on signal processing on an experiment with a dedicated train running on a track equipped with a track circuit. The second objective is to present a strategy to test new detection criteria on commercial zones over a long period of time (a few months) with the help of the PEGASE acquisition board. PEGASE has been developed by IFSTTAR and the presented work is the result of SNCF/IFSTTAR collaboration

Teaching Real-Time Scheduling Analysis with Cheddar

National audienceThis article is a presentation of the Cheddar toolset.Cheddar is a GPL open-source scheduling analysis tool.It has been designed and distributed to allow students to understand the main concepts of the real-time scheduling theory.The tool is built around a simplified ADL (Architecture Description Language)devoted to real-time scheduling theory. Students can directly build their real-time systems models with this ADL andits associated editor, however, it is expected that they use modeling tools to illustrate how scheduling analysis fits in an engineering process.In this article, we introduce the Cheddar ADL and the scheduling analysis features of Cheddar. We alsopresent how Cheddar is implemented and how it can be adapted to specific requirements.Two examples of use of Cheddar are then described.Finally, in the annex of this article, teachers may find a sample of hand-outs that may be used to illustrate real-time scheduling theory with their students

La guerre « pacificatrice » de 1720 : la lutte sanitaire contre l'épidémie de peste de Marseille et sa représentation par la monarchie absolue

International audienceApparue à Marseille au début de l'été 1720, la dernière épidémie de peste française envahit rapidement la Basse-Provence en menaçant de se répandre en Languedoc et le long du Rhône vers Lyon. Contre cette offensive destructrice, à partir de septembre 1720 et pour plus de deux ans, la monarchie prit pour la première fois en France la tête de la lutte sanitaire. Un vaste dispositif de défense et de mise en siège des régions attaquées se déploya sur le terrain. Il fut commandé à Paris par un « Conseil de santé » ministériel créé auprès du Régent Philippe d'Orléans, et en province par des généraux comme le plus important de l'époque, le maréchal de Berwick. Ce n'est pas par artifice et avec difficulté que le registre militaire fleurit dans l'évocation de ce dramatique épisode : la riposte à la peste fut souvent guerrière. C'est suivant le mode militaire que la monarchie fit alors la guerre à cet autre fléau, qu'elle construisit un véritable dispositif de guerre, soutenu par une économie de guerre, une conception et une propagande de guerre ! À titre d'illustration, je publie en annexe (fig. 1) l'Ordonnance militaire d'un commandant du « front » du Rouergue, un genre de document très fréquent dans les archives monarchiques de la politique sanitaire, que je commenterai souvent dans mon développement. Mais pouvait-il s'agir d'une vraie guerre ? Si cette interprétation correspondait pour partie à des réalités de ce temps et à des conceptions héritées du XVII e siècle, elle se heurtait aussi à d'autres, à un contexte nouveau. La monarchie dut constamment réviser ses positions et mettre de l'eau dans son vin, ou plutôt de la paix dans sa guerre. Au mieux, même la politique sanitaire contre la peste fut ainsi une « guerre pacificatrice » dans laquelle, en fait, la paix domina la guerre. Au même moment, la Régence du jeune Louis XV réussissait à déconnecter le régime absolutiste hérité du Grand Roi de la guerre, un moteur essentiel de son développement au XVII e siècle mais devenu un frein insupportable avec les deux dernières et terribles guerres de Louis XIV. La France, ses populations comme son gouvernement aspiraient à la paix, ce qui constituait d'ailleurs l'objectif fondamental de la politique étrangère nouvelle du duc d'Orléans et de son ministre Dubois. Dans ce contexte contradictoire, nous chercherons à comprendre comment la politique sanitaire royale contre la peste de Marseille fut l'un des axes principaux du retournement de la monarchie de la guerre vers la paix