Search

International audience; Model checking is an effective way to verify behaviours of an agent-based simulation system. Three behaviours are analysed: operational, control, and global behaviours. Global behaviours of a system emerge from operational behaviours of local components regulated by control behaviours of the system. The previous works principally focus on verifying the system from the operational point of view (operational behaviour). The satisfaction of the global behaviour of the system conforming to the control behaviour has not been investigated. Thus, in this paper, we propose a more complete approach for verifying global and operational behaviours of systems. To do so, these three behaviours are firstly formalized by automata-based techniques. The meta-transformation between automata theories and Kripke structure is then provided , in order to illustrate the feasibility for the model transformation between the agent-based simulation model and Kripke structure based model. Then, a mapping between the models is proposed. Subsequently, the global behaviour of the system is verified by the properties extracted from the control behaviour and the operational behaviour is checked by general system performance properties (e.g. safety, deadlock freedom). Finally, a case study on the simulation system for aircraft maintenance has been carried out. A counterexample of signals sending between Flight agent and Plane agent has been produced by NuSMV model checker. Modifications for the NuSMV model and agent-based simulation model have been performed. The experiment results show that 9% out of 19% of flights have been changed to be serviceable. behaviours and operational behaviours; Model transformation.

International audience; Most existing methods for time series clustering rely on distances calculated from the entire raw data using the Euclidean distance or Dynamic Time Warping distance. In this work, we propose to embed the time series onto higher-dimensional spaces to obtain geometric representations of the time series them- selves. Particularly, the embedding on R n ×p , on the Stiefel manifold and on the unit Sphere are analyzed for their performances with respect to several yet well-known clustering algorithms. The gain brought by the geometrical representation for the time series clustering is illustrated through a large benchmark of databases. We particularly exhibit that, firstly, the embedding of the time series on higher dimensional spaces gives better results than classical approaches and, secondly, that the embedding on the Stiefel manifold - in conjunction with UMAP and HDBSCAN clustering algorithms - is the recommended frame- work for time series clustering.

International audience; This paper addresses the problem of Fault Classification and Prediction (FCP) without sufficient data in aircraft maintenance. An innovative approach based on Agent-Based Simulation System (ABSS) and the Fuzzy-Rough Nearest Neighbour (FRNN) method is proposed. To do so, a framework for integrating the FRNN approach into ABSS is firstly provided. The concept and architecture models of FRNN-ABSS are then used to describe the FRNN-ABSS system. Subsequently, random and sequence strategies are designed for the FCP of the engine. An algorithm for integrating the FRNN method into ABSS is also developed to automate FCP. Finally, the experiments analysing the impact of different strategies on maintenance costs and service level have been conducted. The results show that the approach proposed has achieved success for random and sequence strategies: 9.3% and 2.5% of maintenance costs have been saved; 4.17% and 12.5% of delayed flights have been changed into on-time flights.

International audience; Clustering is an unsupervised machine learning method giving insights on data without early knowledge. Classes of data are return by assembling similar elements together. Giving the increasing of the available data, this method is now applied in a lot of fields with various data types. Here, we propose to explore the case of time series clustering. Indeed, time series are one of the most classic data type, and are present in various fields such as medical or finance. This kind of data can be pre-processed by of dimension reduction methods, such as the recent UMAP algorithm. In this paper, a benchmark of time series clustering is created, comparing the results with and without UMAP as a pre-processing step. UMAP is used to enhance clustering results. For completeness, three different clustering algorithms and two different geometric representation for the time series (Classic Euclidean geometry, and Riemannian geometry on the Stiefel Manifold) are applied. The results are compared with and without UMAP as a pre-processing step on the databases available at UCR Time Series Classification Archive www.cs.ucr.edu/ ∼ eamonn/time series data/.

The fourth industrial era, the digitisation of production and the emergence of digital twin involve the hyper-connection of all industrial equipment and especially Automated Production Systems (APSs). Nevertheless, the acquisition of data within these machines remains complicated. APS is an expensive invest, composed of many heterogeneous equipments, they are made for having a long lifespan. So, industries rely on old equipment and it is not possible to wait new Industry 4.0-compatible APSs to follow the digital evolution. A solution is to retrieve data from the APSs through their Programmable Logic Controller (PLC), with industrial networks, like the Modbus. The PLC knows the APS state with sensors and pilots the APS with actuators; all this information is stored into variables is the PLC memory, referenced with addresses. Due to several factors, such as heterogeneous data, lack of PLC program documentation or no automation specialist, the data collection is a complicated and time-consuming task. There are difficulties in linking the desired information and the memory addresses. The aim of this contribution is to propose a method for identifying addresses, through photos of APS, a history of memory values and an a posteriori declaration of viewed events with photos. This method must be suitable for non-specialists.

International audience; Emergency departments (ED) in France are jeopardized each winter by the respiratory viruses. To limit the impact of those viruses, it is essential to have a better understanding of their impact on the patient flow. To tackle this, we propose in this work to use in conjunction ICD-10 code and laboratory-confirmed data with the aim of extracting a relevant patient flow. We first take benefice of the almost periodicity of both clinical diagnosis and laboratory-confirmed data and we embed next the underlying time series on the Stiefel manifold. The distance in the Stiefel manifold is finally used to extract clinical codes which are the nearest to the laboratory-confirmed time series. The results reveal that some of the respiratory and cardiac disorders codes have the same behaviours than that of the winter circulating viruses. At least, the Flag mean is employed to dispose of a picture of both the patient flow and the the length of stay for patients who might be infected by winter viruses.

International audience; Operational support is a key issue for aircraft maintenance, which aims to improve operational efficiency and reduce operating costs under the premise of ensuring flight safety. Although many works have emerged to achieve this aim, they mostly address the concept of maintenance systems, the relationship between stakeholders and the loop of maintenance information separately. Hence, the cooperation between stakeholders could be impeded especially when urgent decisions should be made, relying on historical data and real-time data. In this paper, we propose an innovative design of an autonomous system supporting the automatic decision-making for maintenance scheduling. The design starts from the proposition of the analysis framework, to concept formulation of the system, to information transitional level interface, and ends with an instance of system module interactions. The underlying architecture illustrates the high-level fusion of technical and business drives; optimizes strategies and plans with regard to maintenance costs, service level and reliability. An agent-based simulation system is developed as a proof to illustrate the feasibility of the system principle and algorithms. Furthermore, the simulation experiment analyzing the impact of maintenance sequence strategies on maintenance costs and service level has demonstrated the algorithm functionality and the feasibility of the proposed approach.

Part 1: Building Information Modeling; International audience; Nuclear decommissioning is a huge disaster and cumbersome mechanism to han-dle, after critical analysis and rigorous review it is found that PLM and BIM ap-proaches seem interesting in this field to support the business needs in terms of collaboration, information exchange and traceability all over the decommissioning process. This paper analyses the scientific and industrial literature to extract the requirements for the deployment of a mixed BIM-PLM approach in the nuclear decommissioning context.

Cyber-Physical Systems (CPS) are considered as the emerging components for Industry 4.0, the state-of-the art and standard CPS architecture playing the major role in understanding the nature of the industrial landscape. The key problem with traditional CPS architectures is that they are not up-to-mark and convincing to fulfil the needs of smart industries, as they merely consider vertical and horizontal integration with three components (i.e., human, cyber and physical components) integration. Currently, CPS lack adopting and highlighting the key interfacing elements which are vital for Industry 4.0. So, to remedy these problems and bridge the gap between concepts and implementing, this paper proposes to enhance the 3C CPS architecture based on the traditional 3C one for Industry 4.0 by adopting the main interfacing elements such as connectors, protocols, and sub-elements, for example human, cyber and physical parts. Hence, it can be said that the proposed enhanced 3C CPS architecture plays a significant role and will be considered as a guideline and application for future smart manufacturing CPS systems and industries.

International audience; Fourth Industrial revolution (Industry 4.0) has entirely reshaped the landscape of the global world from both enterprise and academia aspect. In the meantime Cyber-Physical System (CPS) has proven its existence by effectively monitoring, analyzing, automating and communicating with every corner. So, wireless connectivity in the industrial world is considered as the challenging issues to be tackled. Sensor based technologies in association with wireless communication are playing main role in Industry 4.0 and CPS environment to make the whole world as smart, sharp and dynamic place. Thus, smart factories must be built by introducing the sensor enabled communication entities such as, CPS, Wireless Sensor Networks (WSNs) with strong and reliable network connection. So, this paper selects the suitable wireless connectivity in Industry 4.0 by focusing at network metrics for instance, latency, reliability, longevity, and throughput. Besides, the critical wireless needs of the CPS based Industry 4.0 are observed and verified through rigorous literature than wireless network and communication technology is proposed from the pool of classical methods. That proposed wireless networks and technology will lead to the future CPS problems in the light of any standard.

Part 12: Modular Design and Products and Configuration and Change Management; International audience; In the design phase, an effective performance evaluation on the information system model for aircraft maintenance helps better iteratively refine the system design. Although many works have emerged to achieve this aim, complex systems are hard to be completely described and the consideration of real-world processes is missing. Thus, how to investigate the system performance with consideration of the real-world aircraft maintenance is our focus. From our point of view, an agent-based simulation modeling is a promising approach to overcome such problem. In this paper, we develop an agent-based simulation model for the whole maintenance process, focusing on cooperation among sub business processes. This model describes the flight process, cooperation between stakeholders and failure repairs, where scheduled/unscheduled maintenance and with/without uncertain event scenarios have been addressed. The performance evaluation of this model is based on the analysis of impacts of key factors on the airline's service level and maintenance cost.

International audience; Enterprise information systems (EIS) are directly implied in the global performance of an organisation. Nevertheless, their potential rigidity in comparison with the required fast evolution of the supported organisation remains an important open research question. The proposed research work aims to define and evaluate the agility of an EIS, in order to assist both software engineers and business managers in EIS improvement projects. In particular, a framework is proposed to structure the different existing metrics on agility according to the improvements needs and the intrinsic characteristics of an information system.

International audience; The Cyber-Physical System (CPS) is a concept describing a broad range of complex, multidisciplinary , physically-aware next generation engineered systems that integrate embedded computing technologies (cyber parts) into the physical world. CPS is a broad area of engineering which supports applications across emergency response, air transportation, critical infrastructure, health care and medicine, intelligent transportation, robotic for service, and special smart manufacturing. In particular, CPS is the core technology enabling the transition from Industry 3.0 to Industry 4.0 and is transforming global advanced manufacturing. This paper provides a review of CPS 5 components architecture for manufacturing as well as of CPS components challenges for manufacturing. It then focuses on the standardization challenges and provides a complete review of international standards. From this study we show that there is need for CPS components to be standardized in order to achieve the success of Industry 4.0. A framework of CPS 5 main components for manufacturing based on standards is proposed.

The level of efficiency achieved in the diffusion of knowledge within an organisation is acknowledged to be a competitive advantage. As a result, various means have emerged to help share this knowledge. Among the various existing solutions, the use of parameterised files consistently encapsulating data of a refined level of granularity (e.g. figures, words, etc.) is a well-known practice. However, these files - which we will call Parameterised Knowledge Objects (PKOs) - often exhibit redundancy. This has led to a need for mapping, a fastidious work with no added value, which slows down the product redesign process. The goal of this article is to propose a conceptual model for the implementation of an automated tool to manage exchanges between these PKOs. The implementable nature of the model was validated by the development of a demonstrator, tested on an application provided by our industrial partner-the Renault Powertrain Technology Design Department.

This paper presents a first step in the elaboration of a semantic-based modelling environment addressed to the conceptual design phase of an industrial product. Up to now, shape generation and manipulation in aesthetic design are still based on low-level geometric tools that come from the classical computer-aided design paradigm. On the other hand, the design of a product is mainly driven by designers’ creativity and high-level constraints. To capture and structure the semantics embedded in the first sketches representing the product, an ontology has been devised to guide more easily the generation and manipulation of curves that are basic elements of the product description in the early design phase. This ontology includes a taxonomy of the aesthetic curves in the automotive field and a curve manipulation setting based on a shape grammar, creating explicit connection between the two contexts.

The level of efficiency in the dissemination of knowledge within an organization is recognized as being a competitive advantage. Therefore, various means appeared in order to share it. Among the existing ways, the use of documents and files to encapsulated consistent knowledge of refined granularity (figures, words, etc.) is a well-known practice. However, the latter sometimes complicates its extraction or reuse in product re-development project. For a large company, improvement resides in the need to implement veritable design logistics covering also this knowledge of refined granularity. The purpose of this chapter is to propose a solution to support the automated sharing of this type of knowledge in the context of a product design process. This solution is based on an information system, the architecture of which will be presented and partially validated by the implementation of an application case provided by our industrial partner, Renault-DIM (Mechanical Engineering Department).

Effective and efficient information management and knowledge sharing has become an essential part of more and more professional tasks in the Product Development Process. Among the varius Knowledge Management technologies, ontologies offer new possibilities for representing, handling and retrieving product related knowledge, and for online collaboration. We conceived a Product Design Ontology (PDO) which especially addresses researchers in industrial product design and engineering analysis who need to share shape data and to develop software tools. In particular, we formalised the task-specific information associated to a shape, and the functionality and usage of shape processing methods in specific tasks of the design workflow. The PDO, thanks to the ontologydriven metadata on shapes and tools, may be also useful in industry on the one hand for training and for retrieving shape-related information, on the other hand for supporting benchmarking of processing tools and gathering the knowledge about shape processing workflows. Science Foundation Ireland; Irish Research Council for Science, Engineering & Technology

International audience; Computer-Aided Geometric Design modelers are now based on powerful mathematical curve and surface models, but there is still a considerable need for efficient tools to handle, analyze and modify these objects. Designing product shapes using geometric operations on free-form curves and surfaces is still a tedious task. Moreover, designers would prefer to use meaningful tools to concentrate on design objectives expressed in terms of functionalities and constraints related to engineering topics and technical matters. This explains why constraint modeling in CAGD is an important challenge for the forthcoming years and the paper aims at setting up some of its foundations. The corresponding global modeling approaches already proposed in CAD are first exposed. The specific existing techniques for handling constraints on curves and surfaces are then surveyed. A synthesis of these techniques and our current studies allows us to suggest a classification of the different constraints which ought to be taken into account in a constraint based modeling CAGD software. Open issues in the context of engineering design are finally emphasized.

This paper addresses the designers’ activity and in particular the way designers express an object shape in 2D sketches through character lines and how these lines form a basis for sketching shapes in 3D. The tools currently available in commercial CAS/CAD systems to manipulate the digital models are still not sufficiently suited to support design. In this paper, the so-called fully free-form deformation features (d-F4) are introduced as a modelling method to take into account the curve-oriented stylists’ way of working. Both the advantages of a free-form surface deformation method and a feature-based approach are merged to define these high-level modelling entities allowing for a direct manipulation of surfaces through a limited number of intuitive parameters. Such features incorporate several characteristics designed to handle the uncertainties and/or inconsistencies of the designer’s input during a sketching activity. In addition, a d-F4 classification is proposed to enable a fast access to the desired shape according to its semantics and characteristics. The work is being carried out in the scope of the activity of AIM@SHAPE Network of Excellencesupported by the European Commission, VI Framework, IST Contract No. 506766.

Part 4: Capture and Reuse of Product and Process Information; International audience; Experiments in a laboratory or a company, either physical or virtual, generate a large amount of data and information (raw data, consolidated results, experimental conditions, etc.) that has to be managed in order to preserve and enhance the knowledge and the expertise of the organization, especially when turnover happens. If simulation data management has been especially explored and standardized (STEP AP 209 for instance), experimental data did not create the same interests and only standard data management tools are proposed. In this paper, we propose an ontology to capitalize such information and knowledge, with an efficient reuse objective. This ontology, for which specific taxonomies have been defined according to the relevant literature of the domain, is illustrated on a set of data on previous experimental campaigns, corresponding to two kinds of mechanical experiments: tribology tests and material characterization tests.