Portail des publications scientifiques IMT Mines Alès
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Evaluation of the Digital Product Passport for Remanufacturing: A Case Study Using Asset Administration Shell
No full textInternational audienceRemanufacturing extends product lifecycles and reduces waste, but its success depends on effective information exchange throughout the value chain. This article evaluates the impact of Digital Product Passport (DPP) on the efficiency of remanufacturing from operational, environmental, and social perspectives. A DPP integrated with a digital thread architecture was tested in a controlled experiment across two laboratories, simulating a real-world remanufacturing scenario. The study compared two approaches: one without DPP and one utilizing DPP for improved decision-making. The results showed that the DPP significantly reduced the remanufacturing cycle time by minimizing the variability in quality control. However, there are potential negative effects on environmental and social metrics. While DPPs enhance operational efficiency, further investigation is needed to understand their broader implications and establish protocols for their sustainable use
From settling to rheology and hydration: How fine fractions govern the behavior of cement-based suspensions
No full textInternational audienceThis study investigates the role of fine particles in governing macroscopic behaviors of suspensions, in particular, cement-based pastes. Granulometric analyses were performed on both raw and binary systems of Portland cement with limestone filler re-grinded or not (LF2, LF1), and fly ash (FA) at various substitution rates (0–100 % vol) to modify fine particle content and identify a particle size threshold. Based on granulometric analyses, a threshold of 5 μm was justified and chosen for subsequent investigation. Suspension stability was assessed using Turbiscan Lab, measuring both settling velocity and supernatant clarity. The results indicate that systems with a higher fine fraction, such as those with LF2 (97.6 %), exhibit enhanced stability, as evidenced by significantly reduced settling velocity compared to LF1 (54.4 %) that demonstrates moderate stability, and FA (34.4 %) that displays pronounced instability. Rheological measurements were performed on raw and 50 % binary systems, and the results revealed that systems with a higher fine fraction exhibit a higher storage modulus G', notably LF2 compared to LF1 and FA, and OPC-50LF2 compared to OPC-50LF1 and OPC-50FA, indicating a denser structural network. Additionally, systems with a high fine fraction displayed a lower percolation threshold confirming the enhanced ability of fine particles to form interconnected networks. Isothermal calorimetry further showed that replacing 50 % of OPC with LF2 and LF1 leads to an increase in the intensity of the main hydration peak by 58 % and 47 %, respectively, compared to pure OPC, indicating that the nucleation-precipitation effect is more pronounced when more fine particles in the system
Microclimate, Soil and Plant Dataset From a Mediterranean Urban Canyon With Irrigated Planters
No full textInternational audienceDataset obtained from a fully instrumented experimental urban street canyon, located on a research site in Montpellier (France, Mediterranean climate) and monitored between 21 July 2023 and 31 July 2024. This east–west canyon consists of two parallel concrete walls (height 2.3 m, length 12 m, width 5 m). Three nearly adjacent planters (height 0.9 m, length 2.3 m, width 0.8 m) are aligned along its inner north wall and contain climbing plants of the Lonicera japonica species. Three other nearly adjacent planters (height 0.9 m, length 2.3 m, width 1.1 m) are aligned along its inner south wall and contain shrub plants of the Abelia grandiflora species. Each planter includes 11 sensors to measure soil temperature, water content and matric potential, collecting data every 10 min. Drip irrigation was used and each series of planters received identical irrigation amounts. The irrigation strategy changed several times, to monitor the impacts of irrigation on the overall water balance of the soil–plant–atmosphere system, especially on the local microclimatic variables. A dense network of 102 sensors was installed to monitor wind direction and velocity, air temperature, relative humidity, radiation, grey globe temperature and rainfall at 1.3 m above the ground, which is a standardised measurement height for determining the variables used to quantify thermal comfort indices. This dataset supports (i) understanding thermal, radiative and aerodynamic processes in urban canyons, (ii) detecting irrigation impact on microclimate, (iii) validating CFD‐based microclimate models and (iv) identifying methods to manage urban heatwaves through water resource optimisation. By encompassing a full year of seasonal and climatic variability, this study is the first to evaluate the combined effects of vegetation type and irrigation on urban thermal comfort in a Mediterranean context, providing a significant contribution to urban microclimate research
Exploring the Digital Thread: A Comprehensive State of the Art Review
No full textInternational audienc
A digital twin engineering method for nuclear vitrification process: from capabilities analysis to architectures
No full textInternational audienceThis paper explores first the concept of digital twin system and second how such digital twin system engineering must be done and managed for a manufacturing application in the nuclear sector. More specifically, this article focuses on engineering the digital twin system of a vitrification process for nuclear waste. To this purpose several concepts from literature and practices analysis are introduced. A methodological approach is then proposed to engineer such digital twin systems thanks to expected end-users’ usages, physical system nature and characteristics or expected capabilities that must be then considered to satisfy these end-users. The approach crosses normative references inspired by Model Based Systems and Software Engineering (MBSSE), Digital Twin system definition, capabilities versus expected usages definition and on both requirements and architecture engineering guides being inspired by System Engineering principles
Optimizing Nanoparticle Design for Selective Targeting of Breast Cancer Cells
No full textInternational audienceRecent efforts in cancer targeting have focused on nanoparticle (NP) drug delivery, yet the complexity of NP uptake makes experimental studies challenging. To streamline this, numerical models help identify key parameters. This study's model, focusing on elliptical NPs, aims to optimize NP aspect ratios for selective uptake by breast cancer cells. Mechanical properties of cells were taken from literature, and the model suggests that non-deformable NPs with aspect ratios between 1/3 and 1/2 are optimal for selective cancer cell internalization. These promising results require experimental validation
A Novel Approach to Cost Estimation in Lot Sizing with Uncertain Lead Times
No full textInternational audienceThe lot sizing problem involves meeting the demand of the clients of a given retailer by placing orders with different suppliers. Decision-making models were developed to minimize the retailer's total cost while considering their retailers' different characteristics, such as their capacities, prices, and lead times. However, when integrating uncertainty into the environment, this challenging problem becomes even more complex, and the exact methods developed need extremely long computational time to go over all the possible scenarios. This paper proposed a novel formulation to minimize the operations needed when finding the optimal solution to the lot sizing problem under uncertain lead times.</div
Étude de l’influence de l’impact environnemental sur le choix des consommateurs : Application à de la vente en vrac de gel douche
No full textNational audienceD’après le baromètre GreenFlex ADEME de la consommation responsable 2024 65 des Français déclarent changer de magasin pour se tourner vers des options plus engagées. Ainsi, la prise de conscience des enjeux environnementaux et sociaux de nos actes de consommation semble se transmettre à la prise de décision, le lien entre achats et environnement semble clairement établi par les citoyens. D’autre part, afin de lutter contre la crise du plastique, de plus en plus d’alternatives, telles que des emballages réutilisables, apparaissent et permettent ainsi de diminuer la production de déchets plastiques à la source, dans une logique d’économie circulaire. L’objectif de cette étude est d’étudier comment des résultats d’impacts environnementaux évalués par analyse de cycle de vie ( sur des emballages réutilisables, peuvent influencer le choix des consommateurs. Dans une première partie, des indicateurs environnementaux pour deux types d’emballages de gel douche sont évalués par ACV. L’analyse de cycle de vie est réalisée selon les normes ISO 14040 14044 du berceau à la tombe La modélisation est effectuée avec le logiciel OpenLCA, les données d’inventaire proviennent essentiellement de données de terrain, de la littérature et de base de données. Une fois les indicateurs environnementaux évalués l’influence de ces résultats sera évaluée sur un panel de consommateurs par le biais d’une enquête en ligne, permettant de mieux comprendre les moteurs de décision des consommateurs et d’identifier de potentielles caractéristiques socio-économiques, démographiques présentes chez les individus pour lesquels l’information environnementale donnée influe sur le choix
Fire resistance of lightweight earth concretes: the evaluation of the thermal insulation criterion at the cone calorimeter test scale
No full textInternational audienceLightweight earth concretes present a potential alternative as insulat-ing construction materials due to their good thermal and hygrothermal properties. In addition, they can be prepared from renewable natural resources, such as raw earth and agricultural residues, mitigating the energetic footprint of currently used construction materials. Nevertheless, there is still not enough information about the fire resistance of these materials, a factor that impairs their wider ap-plication in construction. In order to deeper understand the fire behavior of these materials, especially concerning their thermal insulation properties, this work studied the thermal transfer of lightweight concretes composed of raw earth and wheat straw, with different densities. The tests were performed using a cone cal-orimeter in a vertical position, instrumented with a pyrometer, a thermal camera and thermocouples to monitor the temperature evolution across the concrete sam-ples. The results show the first insights about the influence of density on the ther-mal transfer and on the velocity of the heat front propagation
FORT-RAJ: a fisheye-optimized deep learning model for real-time trajectory prediction
No full textInternational audienceFisheye cameras, renowned for their ultra-wide panoramic field of view, have become essential tools in applications requiring extensive area monitoring. However, their unique optical properties introduce significant image distortions, rendering traditional trajectory prediction algorithms ineffective when applied to fisheye imagery. To address this challenge, we introduce Fisheye-Optimized Real-Time Trajectory prediction (FORT-RAJ), a novel hybrid artificial intelligence approach capable of both adapting to fisheye distortions and accurately predicting pedestrian trajectories in real time. From a technical perspective, FORT-RAJ combines the strengths of two state-of-the-art models: Fisheye Online Realtime Tracking (FORT), a distortion-aware model designed for fisheye cameras but limited to pedestrian tracking, and Graph- and Attention-based multi-agent Trajectory prediction model (GATraj), a powerful prediction framework not originally compatible with fisheye distortions. By integrating the fisheye adaptation capabilities of FORT with the predictive power of GATraj, FORT-RAJ overcomes their individual limitations and provides an end-to-end solution that is both distortion-aware and capable of accurate future movement prediction. The effectiveness of the proposed approach was rigorously evaluated on two distinct datasets, namely HABBOF and Caplogy. Experimental results revealed the superiority of FORT-RAJ, achieving an Average Displacement Error of 0.39 ms and 0.38 ms, and a Final Displacement Error of 0.43 ms and 0.42 ms for HABBOF and Caplogy, respectively. These results underscore the model’s high precision in predicting pedestrian trajectories, even under challenging conditions