Diagnosis on a sliding window for partially observable Petri nets

summary:In this paper, we propose an algebraic approach to investigate the diagnosis of partially observable labeled Petri nets based on state estimation on a sliding window of a predefined length $h$. Given an observation, the resulting diagnosis state can be computed while solving integer linear programming problems with a reduced subset of basis markings. The proposed approach consists in exploiting a subset of $h$ observations at each estimation step, which provides a partial diagnosis relevant to the current observation window. This technique allows a status update with a "forgetfulness" of past observations and enables distinguishing repetitive and punctual faults. The complete diagnosis state can be defined as a function of the partial diagnosis states interpreted on the sliding window. As the analysis shows that some basis markings can present an inconsistency with a future evolution, which possibly implies unnecessary computations of basis markings, a withdrawal procedure of these irrelevant basis markings based on linear programming is proposed

A strategy for Estimation in Timed Petri nets

International audienceThe aim of the paper is the estimation of sequences in Timed Petri nets. We propose a general strategy composed of two phases: The first phase considers the logical aspect only and suggests candidate count vectors where the second one checks the existence of a relevant time sequence for a Timed Petri net and generate a subspace of time sequences for a given candidate vector

Linear Algebraic Formalism for State Estimation of Labeled Petri Net

International audienceIn this paper we present an algebraical approach for the state estimation of discrete event systems, partially observed and modeled by labeled Petri nets. Our estimation approach is based on the on-line observation of firing occurrences of some transitions to determine the set of all possible actual sequences and markings. This approach has been used to minimize the computation time and space for the state estimation using an off-line procedure

Host-Range shift between emerging P[8]-4 Rotavirus and Common P[8] and P[4] Strains: Host-range shift of P[8] rotaviruses

International audienceIn Tunisia, we observed that rotavirus P[8]-3 and P[4] in young children with gastroenteritis associate with the secretor histo-blood-group phenotype. Inversely, the emerging P[8]-4, representing 10% of cases, was exclusively found among nonsecretor patients. Unlike VP8* from P[8]-3 and P[4] strains, the P[8]-4 VP8* protein attached to glycans from saliva samples regardless of the donors Secretor status. Interestingly, a high frequency of FUT2 enzyme deficiency (nonsecretor phenotype) was observed in the population. This may allow co-circulation of P[8]-3 and P[8]-4 strains in secretor and nonsecretor children, respectively

Host-Range Shif between Emerging P[8]-4 Rotavirus and Common P[8] and P[4] Strains

International audienceIn Tunisia, we observed that rotavirus P[8]-3 and P[4] in young children with gastroenteritis associate with the secretor histo-blood-group phenotype. Inversely, the emerging P[8]-4, representing 10% of cases, was exclusively found among nonsecretor patients. Unlike VP8* from P[8]-3 and P[4] strains, the P[8]-4 VP8* protein attached to glycans from saliva samples regardless of the donors Secretor status. Interestingly, a high frequency of FUT2 enzyme deficiency (nonsecretor phenotype) was observed in the population. This may allow co-circulation of P[8]-3 and P[8]-4 strains in secretor and nonsecretor children, respectively