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Rapport de Prospective Conseil Scientifique CNRS Ingénierie (Ex: INSIS)
No full textCe document est le rapport de prospective de CNRS Ingénierie, réalisé par le Conseil Scientifique de l'INSIS (CNRS Ingénierie) pour la mandature 2019-2023
Employing BERT model backed by expert knowledge to extract from textual media event of interest along container shipping supply chain
No full textInternational audienceContainer is the keystone of multimodal supply chains. As container shippinginvolves numerous actors and because of immense volumes, associated data is teeming. IoT now enables us to see through this mist at the container level. We therefore, we propose a demonstration service to extend visibility by utilizing insights offered by IoT data inherent to containers. The location of containers serves as a starting point to gather information about higher-level circumstances. We armed the service with machine learning algorithms for detecting events of interest along the supply chain through textual exogenous data. An automated information extraction methodology based on BERT model backed by expert knowledge has been implemented. It is illustrated here on a use case to detect climatic events along tracked container route by retrieving tweets from twitter API
Sliding and merging of strongly sheared droplets
No full textInternational audienceA mathematical and numerical framework is proposed to compute the displacement and merging dynamics of sliding droplets under the action of a constant shear exerted by a gas flow. An augmented formulation is implemented to model surface tension including the full curvature of the free surface. A set of shallow-water evolution equations is obtained for the film thickness, the averaged velocity, an additional quantity (with dimension of a velocity) taking into account the capillary effects and a tensor called enstrophy. The enstrophy accounts for the deviation of the velocity profile from a constant velocity distribution. The formulation is consistent with the long-wave expansion of the basic equations with a conservative part and source terms including the effect of viscosity, in the form of a viscous friction and the effect of the shear stress. The model is hyperbolic with generalised diffusion terms due to capillarity. Finally, our model is completed with a disjoining pressure formulation that is able to account for the hysteresis of the static contact angle. In this formulation, the advancing or receding nature of the contact line is assessed by the accumulation or reduction of mass of the droplet at the contact line. Simulations of sliding water droplets are performed with periodic boundary conditions in a domain of limited size. Hysteresis of the static contact angle causes a slowdown of the drops and a delay in the sequence of coalescence of the drop
Path integrals formulations leading to propagator evaluation for coupled linear physics in large geometric models
No full textInternational audienceReformulating linear physics using second kind Fredholm equations is very standard practice. One of the straightforward consequences is that the resulting integrals can be expanded (when the Neumann expansion converges) and probabilized, leading to path statistics and Monte Carlo estimations. An essential feature of these algorithms is that they also allow to estimate propagators for all types of sources, including initial conditions. The resulting practice is a single Monte Carlo run, for one given set of sources, producing propagators that can later be used with any other set of sources for fast simulations, typically as parts of optimization, inversion, sensitivity analysis and command control algorithms. The present paper illustrates how this practice can be extended to problems involving several interacting physics, provided that their coupling is only at the boundary of the system or at interfaces between sub-parts, and may itself be given the form of a second kind Fredholm equation. A full practical implementation is described as part of the Stardis code, with the example of transfering heat via the coupling of radiation, reaction-diffusion and convection as typically expected in the multidisciplinary context of urban climate modeling. Besides, we show how recent advances in computer graphics indicate that these algorithms can be made numerically extremely efficient when facing large CAD geometries: computing the propagator becomes strictly independent of the geometry refinement, i.e. is identical whatever the number of triangles and tetraedra used to numerize the surface and volume descriptions. To the best of our knowledge this is the first report of propagator computations that remains practical for coupled physics in large CAD geometries
An Agent-Based Simulation Platform for a Safe Election: From Design to Simulation
No full textInternational audienceManaging the logistics and safety of an election system, from delivering voting machines to the right locations at the right time to ensuring that voting lines remain reasonable in length is a complex problem due to the scarcity of resources, especially human poll workers, and the impact of human behavior and disrupting events on the performance of this critical system. These complexities grew with the need for physical distancing during the COVID-19 pandemic coinciding with multiple key national elections, including the 2020 general presidential election in the USA. In this paper, we propose a digital clone platform leveraging agent-based simulation to model and experiment with resource allocation decisions and voter turnout fluctuations and facilitate “what-if” scenario testing of any election. As a use case, we consider three different concurrent polling location problems, namely, resource allocation, polling layout, and management. The main aim is to reduce voter waiting time and provide visibility of different scenarios for polling and state-level managers. We explain the proposed simulation platform based on Fulton County for the 2020 presidential US election. Fulton County had 238 polling locations in 2020, which provided publicly available voter turnout data. The developed platform realistically models at the county level and at specific locations, suggesting the possible allocation of finite resources among locations in the county and the configuration of each location, accounting for physical, legal, and technical constraints. Multiple realistic scenarios were developed and embedded into the simulation platform to evaluate and verify the different systems. The system performance and key attributes of the election system, such as waiting time, resource utilization, and layout safety, were tested and validated
Dual-scale flow simulation for LCM processes: Simulation of reactive PA6 flow in a fibrous preform forT-RTM process
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Special Issue on “Decision Support Systems in an uncertain world”
No full textIl s'agit d'un "Call for papers" pour le special issue on “Decision Support Systemsin an uncertain world”Relance en janvier 2024 : https://doi.org/10.1111/itor.13435Decision Support Systems (DSS) are designed to assist policy makers (and others) to tackle increasingly complex issues by navigating the different objectives of multiple and diverse stakeholders, while attempting to make decisions that are robust under different circumstances and do not produce undesirable consequences. There is a growing interest in dealing with uncertainty in real-world decision support and a concrete need to generate knowledge from information, as well as from models relying on that information. Furthermore, theoretical, and technological advances, such as Digital Twins, enable DSSs to better support human decision-making capabilities in the modern digital age. The new business models of this era amplify the demand for a customized and intelligent decision support capable of meeting the needs of modern industry, business, and society.This special issue welcomes articles on methodologies and technologies, as well as application-oriented works addressing decision support challenges.The deadline for submissions is November 30, 2023.This Call for Papers is open to the entire community of academics and practitioners. We encourage authors who will present their work at the EWG-DSS 9th International Conference on Decision Support System Technology (ICDSST2023) (https://icdsst2023.wordpress.com/) to submit their manuscripts.Papers will be peer-reviewed according to the editorial policy of the International Transactions in Operational Research (ITOR), published by the International Federation of Operational Research Societies. Contributions should be prepared according to the instructions to authors in the journal homepage. Authors should upload their contributions using the submission site http://mc.manuscriptcentral.com/itor, indicating in their cover letter that the paper is intended for this special issue.Other inquiries should be sent directly to Guest Editors: Ana Paula Cabral Seixas Costa ([email protected]); Daouda Kamissoko ([email protected]) and José Maria Moreno-Jiménez ([email protected])
Vers une démarche sécurisée des erreurs médicamenteuses à l’hôpital
No full textInternational audienceFace aux risques élevés d'événements indésirables liés au processus de la prise en charge médicamenteuse des patients hospitalisés, la promotion de la qualité et de la sécurité des soins est devenue une priorité pour les établissements de santé. La complexité de ce processus de soins peut conduire à des erreurs médicamenteuses avec des conséquences variables, allant de légères à très graves, pour toutes les parties prenantes. Pour assurer la sécurité des patients et réduire les erreurs médicamenteuses, un système de management de la qualité de la prise en charge médicamenteuse, intégrant également une démarche globale de gestion des risques doit être mise en place dans les établissements de santé. Ce travail propose une modélisation de ce processus, pour appréhender sa complexité en promouvant une numérisation au sein de la démarche de gestion de ses risques dans les systèmes hospitaliers soumis à la réglementation française. Cette numérisation repose sur des bases conceptuelles solides permettant de structurer la déclaration des erreurs médicamenteuses, l’implication des techniques et outils de l’Intelligence Artificielle et la Science des Données pour leur classification, l'analyse méthodologique de leurs causes, ainsi que la proposition d’exploiter ce capital pour mieux les gérer ou les prévenir
Foaming of PLA biocomposites by supercritical CO2 assisted extrusion process
No full textInternational audienceIn many industrial fields, the development of porous and lightweight polymer composite structures is of great interest. These structures may have several advantages compared to a massive solid of similar chemical nature, such as better mechanical properties, cushioning, insulation or sound and heat absorption. Three different methods are developed for the foaming of materials: batch, injection and extrusion foaming. These techniques employ highly toxic and harmful substances such as azodicarbonamide as blowing agents, which has increased the use of supercritical fluids as blowing agents, sc-CO2 being the most employed. In addition, petroleum-based thermoplastics are widely used as polymer matrices, but, due to the shortage of fossil resources and the rise of environmental concerns, biopolymers (bio-based and/or bio-degradable, polymers) are more and more used. In this context, the foaming of biopolymers using supercritical CO2 as a blowing agent has become a subject of interest. For this work, polylactic acid (PLA) is employed as the polymer matrix. PLA’s interesting properties have made it the most studied biopolymer, and consequently generated a great amount of interest in different industrial fields. The foaming of PLA biocomposites has been investigated before [1-2], but the effect of fillers on the cellular morphology remains a misunderstood and poorly studied subject.This work aims to explain the effects of size and aspect ratio of a filler as well as its content on the characteristics of PLA foams obtained by supercritical CO2-assisted extrusion process. Short (S) and long (L) cellulose fibres with aspect ratios (lenght/diameter) of 1.5 and 5-7 respectively, have been used as fillers. Fibres were compounded with the polymer through hot melt extrusion at different volume fractions (4 and 12 vol.%) (mass fractions 5 and 15 wt.% respectively). During the extrusion foaming process, two different volumetric flow rates of CO2 were studied (2.5 and 3 mL min-1), and the effect of die temperature was evaluated as well. Techniques as gas pycnometry, scanning electron microscopy (SEM) and modulated differential scanning calorimetry (MDSC) have been used to identify the characteristics of the produced foams