Timed-pNets: A Communication Behavioural Semantic Model for Distributed Systems (extended version)

This paper presents an approach to build a communication behavioural semantic model for heterogeneous distributed systems that include synchronous and asynchronous communications. Since each node of such system has its own physical clock, it brings the challenges of correctly specifying the system's time constraints. Based on the logical clocks proposed by Lamport and CCSL proposed by Aoste team in INRIA as well as pNets from Oasis team in INRIA, we develop timed-pNets to model communication behaviour for distributed systems. Timed-pNets are tree style hierarchical structures. Each node is associated with a timed specification which consists of a set of logical clocks and some relations on clocks. The leaves are represented by timed-pLTSs and non-leaf nodes are represented by timed-pNets including some holes which are filled by leaves or non-leaf nodes. Both timed-pLTSs and timed-pNets node can be translated to timed specifications. All these notions and methods are illustrated on a simple use-case of car insertion from the area of Intelligent Transportation Systems (ITS) and then TimeSquare tool is used to simulate and check the validity of our model.Cet article présente une nouvelle approche pour définir un modéle sémantique comportemental pour des systémes distribués comportant des communications aussi bien synchrones qu'asynchrones. Chaque site dans ce genre de systéme ayant sa propre horloge, définir correctement les contraintes temporelles globales du systéme est un défi. Á partir des concepts d'horloges virtuelles de Lamport, du langage CCSL introduit par l'équipe AOSTE d'INRIA, et du modéle pNets de l'équipe OASIS, nous développons notre modéle Timed-pNets pour exprimer les comportements et la communication de ces systémes distribués. Les Timed-pNets sont des structures hiérarchiques arborescentes. Á chaque noeud est associée une {\sl spécification temporelle} composée d'un ensemble d'horloges et de relations entre ces horloges. Les noeuds feuilles sont representés par des Timed-pLTSs (systémes de transitions paramétrés temporisés), et les autres noeuds sont soit recursivement des Timed-pNets, soit des trous (Holes) destinés á être remplis ultérieurement par des Timed-pNets. Nous définissons des algorithmes permettant de synthétiser la spécification temporelle des Timed-pLTSs et des Timed-pNets. Toutes ces notions sont illustrées sur un exemple de conduite automatisée de véhicules, issue du monde des systémes de transport intelligents (ITS); finalement nous utilisons le logiciel TimeSquare pour simuler notre modéle et en vérifier la validit

Timed-pNets: a communication behavioural semantic model for distributed systems

International audienceThis paper presents an approach to build a communicationbehavioural semantic model for heterogeneousdistributed systems that include synchronous and asynchronouscommunications. Since each node of such systemhas its own physical clock, it brings the challenges of correctlyspecifying the system time constraints. Based on thelogical clocks proposed by Lamport, and CCSL proposed byAoste team in INRIA, as well as pNets from Oasis teamin INRIA, we develop timed-pNets to model communicationbehaviours for distributed systems. Timed-pNets are treestyle hierarchical structures. Each node is associated with atimed specification which consists of a set of logical clocksand some relations on clocks. The leaves are representedby timed-pLTSs. Non-leaf nodes (called timed-pNets nodes)are synchronisation devices that synchronize the behavioursof subnets (these subnets can be leaves or non-leaf nodes).Both timed-pLTSs and timed-pNets nodes can be translatedto timed specifications. All these notions and methods are illustratedon a simple use-case of car insertion from the areaof intelligent transportation systems (ITS). In the end theTimeSquare tool is used to simulate and check the validityof our model

Timed-pNets: A formal communication behavior model for real-time CPS system

International audienceWe propose a semantic model named timed-pNets to de ne hierarchical structures for CPSs as well as its communication behaviors semantic with time constraints. Logical clocks relations are introduced to describe the partial order of event occurring. After setting (time)- boundaries and designing properties, we use the TimeSquare tool to simulate the system and check its properties

Scale-aware Super-resolution Network with Dual Affinity Learning for Lesion Segmentation from Medical Images

Convolutional Neural Networks (CNNs) have shown remarkable progress in medical image segmentation. However, lesion segmentation remains a challenge to state-of-the-art CNN-based algorithms due to the variance in scales and shapes. On the one hand, tiny lesions are hard to be delineated precisely from the medical images which are often of low resolutions. On the other hand, segmenting large-size lesions requires large receptive fields, which exacerbates the first challenge. In this paper, we present a scale-aware super-resolution network to adaptively segment lesions of various sizes from the low-resolution medical images. Our proposed network contains dual branches to simultaneously conduct lesion mask super-resolution and lesion image super-resolution. The image super-resolution branch will provide more detailed features for the segmentation branch, i.e., the mask super-resolution branch, for fine-grained segmentation. Meanwhile, we introduce scale-aware dilated convolution blocks into the multi-task decoders to adaptively adjust the receptive fields of the convolutional kernels according to the lesion sizes. To guide the segmentation branch to learn from richer high-resolution features, we propose a feature affinity module and a scale affinity module to enhance the multi-task learning of the dual branches. On multiple challenging lesion segmentation datasets, our proposed network achieved consistent improvements compared to other state-of-the-art methods.Comment: Journal paper under review. 10 pages. The first two authors contributed equall

Revealing the Biexciton and Trion-exciton Complexes in BN Encapsulated WSe2

Strong Coulomb interactions in single-layer transition metal dichalcogenides (TMDs) result in the emergence of strongly bound excitons, trions and biexcitons. These excitonic complexes possess the valley degree of freedom, which can be exploited for quantum optoelectronics. However, in contrast to the good understanding of the exciton and trion properties, the binding energy of the biexciton remains elusive, with theoretical calculations and experimental studies reporting discrepant results. In this work, we resolve the conflict by employing low-temperature photoluminescence spectroscopy to identify the biexciton state in BN encapsulated single-layer WSe2. The biexciton state only exists in charge neutral WSe2, which is realized through the control of efficient electrostatic gating. In the lightly electron-doped WSe2, one free electron binds to a biexciton and forms the trion-exciton complex. Improved understanding of the biexciton and trion-exciton complexes paves the way for exploiting the many-body physics in TMDs for novel optoelectronics applications