Two Cases of Study for Control Reconfiguration of Discrete Event Systems (DES)

International audienceIn this paper, we propose two cases of study for control reconfiguration of Discrete Event Systems. The main contributions are based on a safe centralized and distributed control synthesis founded on timed properties. In fact, if a sensor fault is detected, the controller of the normal behavior is reconfigured to a timed controller where the timed information replaces the information lost on the faulty sensor. Finally, we apply our contribution to a manufacturing system to illustrate our results and compare between the two frameworks

Time-Based Estimator for Control Reconfiguration of Discrete Event Systems (DES)

International audienceIn this paper, we propose a Time-based estimator method to reconfigure manufacturing systems in case of sensor faults detection. The main idea is to replace the information lost by a timed one. In non-faulty behavior, each sensor is defined through two events: activation and deactivation. Our contribution is to define an estimator model of each event based on different clocks to maintain the same desired behavior of the system in a faulty mode (reconfigured)

CONTRIBUTION A LA COMMANDE DES SYSTEMES A EVENEMENTS DISCRETS TEMPORISES (SEDTS)

International audienceRESUME: Ce papier présente une approche de synthèse de commande sûre de fonctionnement des Systèmes à Evéne-ments Discrets Temporisés (SEDTs), à base de propriétés temporelles. Pour établir cette synthèse, la démarche propo-sée s'appuie sur la modularité des systèmes manufacturiers retrouvée dans les travaux (Qamsane et al., 2014a,b). Un exemple de système automatisé de production vient illustrer nos propos. MOTS-CLES: Systèmes à événements discrets temporisés, théorie de la supervision, commande distribuée, systèmes manufacturiers, modélisation

Contribution to the design of reconfigurable and fault tolerant control for Automated Production Systems

Les travaux présentés dans ce mémoire de thèse entrent dans le cadre de la reconfiguration de la commande des systèmes automatisés de production (SAP) vus comme une classe de Systèmes à Evénements Discrets (SED). La reconfiguration est basée sur la théorie de contrôle par supervision (SCT) et déclenchée suite à une détection des défauts sur la partie opérative (commande tolérante aux fautes). La contribution de ce mémoire est basée sur une synthèse de contrôle sûre fondée sur des propriétés temporisées. Si un défaut de capteur est détecté, le contrôleur du comportement normal est reconfiguré en un comportement dégradé où les informations temporisées compensent les informations perdues sur le capteur défectueux. Le basculement entre le comportement normal et le comportement dégradé est assuré par des règles de reconfiguration. L'objectif principal de notre méthode est d'implémenter le contrôle obtenu dans un automate programmable industriel (API). L'approche développée dans la thèse repose sur une architecture de contrôle distribuée des systèmes automatisés de production pour éviter l'explosion combinatoire récurrente des approches à base de SCT. Pour répondre aux différents objectifs, nous proposons une méthode pour traduire les contrôleurs distribués des deux modes de fonctionnement, ainsi que les règles de reconfiguration en différents grafcets implantables dans un API. L’implémentation de ces différents modèles est vérifiée par une technique de model-checking avant d’être testé sur un jumeau numérique. Enfin, nous appliquons notre contribution à un système réel pour illustrer nos résultats.The research results presented in this thesis falls within the framework of control reconfiguration of Automated Production Systems (APS) seen as a class of Discrete Event Systems (DES). The reconfiguration is based on Supervisory control theory (SCT) and triggered following a plant fault detection (fault tolerant control). The faults considered in this report are sensor faults (a sensor which remains blocked on reading 1 or on reading 0). The main contribution is based on a safe control synthesis founded on timed properties. In fact, if a sensor fault is detected, the controller of the normal behavior is reconfigured to a timed one where the timed information compensates the information lost on the faulty sensor. The switch between normal and reconfigured behaviors is ensured using reconfiguration rules. The main objective of our method is to implement the obtained control into a PLC. To meet the different objectives, we propose a method to translate the distributed controllers of the two operating modes, as well as the reconfiguration rules into different Grafcets implantable in a PLC. The implementation of these different models is verified by a model-checking technique before being tested on a digital twin. Finally, we apply our contribution to a real system to illustrate our results

Noncontiguous multi-tiered spinal tuberculosis associated with sternal localization: a case report

Abstract Background Tuberculous spondylodiscitis is a frequent localization of tuberculosis. Multi-tiered involvement and an association with sternal localization are rare. Case presentation We report a case of multi-tiered tuberculous spondylodiscitis with sternal localization in an immunocompetent 41-year-old Arab woman who had inflammatory bilateral sciatica L5 and S1 and a history of low back pain caused by a trauma. Radiography, computed tomography, and a vertebral biopsy were useful for diagnosis. She reacted well to anti-bacillary treatment despite the occurrence of multiple paravertebral and subcutaneous abscesses. The medullar magnetic resonance imaging control performed at 4 months, 12 months, and 1 year after the end of treatment showed a favorable evolution. Conclusions To avoid the delay of diagnosis, especially in our endemic context, tuberculosis must be evoked usually. This will improve the prognosis of our patients

IFNL4 rs12979860 polymorphism influences HBV DNA viral loads but not the outcome of HBV infection in Moroccan patients

International audienceObjectivesThe interferon (IFN) is known to bridge innate and adaptive immune responses, and to play a critical role particularly against hepatitis B virus (HBV) infection. Defects in IFN signals may result, therefore, in attenuated responses against HBV. Accordingly, polymorphisms in genes coding for immune response effectors may affect the clinical outcome of HBV infection. We analyzed the putative association between IFNL4 rs12979860 polymorphism and the outcome of HBV infection in Moroccan patients.MethodsIn this study, 237 chronic HBV (CHB) patients and 129 spontaneously resolved HBV (SRB) individuals were enrolled and genotyped using a predesigned Taqman allelic discrimination assay.ResultsOur data show a significant increase of HBV DNA loads in patients with IFNL4 rs12979860 CC genotype compared to patients with CT and TT genotypes (p = 0.0008). However, there was no consistent association between IFNL4 rs12979860 polymorphism and the outcome of HBV infection.ConclusionsAlthough IFNL4 rs12979860 polymorphism seems to modulate circulating HBV DNA levels, it is disconnected from chronic disease progression. This observation suggests that the role of rs12979860 in liver disease is restricted to viral control and inactive in the deleterious immune pathology that affects liver tissue. Taken together, our data suggest that rs12979860 CC genotypes could be useful as a predictor of success or failure of IFN-based therapy in chronic HBV-infected patients

Anti-inflammatory potential of Capparis spinosa L. in vivo in mice through inhibition of cell infiltration and cytokine gene expression

Abstract Background Several chronic inflammatory diseases are characterized by inappropriate CD4+ T cell response. In the present study, we assessed the ability of Capparis spinosa L. (CS) preparation to orientate, in vivo, the immune response mediated by CD4+ T cells towards an anti-inflammatory response. Methods The in vivo study was carried out by using the contact hypersensitivity (CHS) model in Swiss mice. Then we performed a histological analysis followed by molecular study by using real time RT-PCR. We also realized a phytochemical screening and a liquid-liquid separation of CS preparation. Results Our study allowed us to detect a significantly reduced edema in mice treated with CS preparations relative to control. CS effect was dose dependent, statistically similar to that observed with indomethacin, independent of the plant genotype and of the period of treatment. Furthermore, our histology studies revealed that CS induced a significant decrease in immune cell infiltration, in vasodilatation and in dermis thickness in the inflammatory site. Interestingly, we showed that CS operated by inhibiting cytokine gene expression including IFN\u3b3, IL-17 and IL-4. Besides, phytochemical screening of CS extract showed the presence of several chemical families such as saponins, flavonoids and alkaloids. One (hexane fraction) out of the three distinct prepared fractions, exhibited an anti-inflammatory effect similar to that of the raw preparation, and would likely contain the bioactive(s) molecule(s). Conclusions Altogether, our data indicate that CS regulates inflammation induced in vivo in mice and thus could be a source of anti-inflammatory molecules, which could be used in some T lymphocyte-dependent inflammatory diseases

Effect of MBOAT7 variant on hepatitis B and C infections in Moroccan patients

International audienceThe outcomes of HBV and HCV infections are associated both with viral and host genetic factors. Here, we explore the role of a genetic variation located in membrane-bound O-acyltransferase domain-containing protein 7 (MBOAT7) gene on spontaneous clearance of HBV and HCV infections and on liver fibrosis. We genotyped MBOAT7 rs641738 polymorphism in 971 consecutive Moroccan subjects, including 288 patients with chronic hepatitis C (CHC), 98 cases with spontaneous clearance of HCV, 268 patients with chronic hepatitis B (CHB), 126 spontaneously cleared HBV infections and 191 healthy controls. MBOAT7 rs641738 variant is not associated with spontaneous clearance of HBV (OR = 0.67, 95% CI: 0.39-1.14; p = 0.131) and HCV infections (OR = 1.33, 95% CI: 0.79-2.23; p = 0.278). Furthermore, multivariable logistic regression analysis adjusted for biologically relevant covariates and potential confounders associated with the risk of liver disease progression revealed that MBOAT7 rs641738 is not associated either with fibrosis progression in CHC group (OR = 1.12; 95% CI: 0.55-2.28; p = 0.761) or with chronic progressive state in CHB patients (OR = 0.81; 95% CI: 0.41-1.61; p = 0.547). We conclude that the variant MBOAT7 rs641738 genotype is not associated with spontaneous clearance of HBV and HCV infections or with the progression of liver disease in chronic hepatitis B or C in a genetic context of Mediterranean patients