Portail des publications scientifiques IMT Mines Alès
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An Hla-Based Automated Approach for the Interoperable Simulation of Collaborative Business Processes
No full textInternational audienceAs collaborative simulations gain prominence, there is a pressing need for methodologies that seamlessly integrate interoperability while safeguarding intellectual property. This paper presents a novel approach rooted in the Model-Driven Architecture (MDA) and combined with the High-Level Ar- chitecture (HLA) standard. This approach expedites the simulation pro- cess by automating the generation of Federation Object Model (FOM) files and federate codes. Distinctly, we produce two federates: one exclusively in Java and another integrating Java with the Discrete Event System Specifica- tion (DEVS), addressing diverse simulation paradigms. Utilizing the Unified Modeling Language (UML) and the Business Process Model and Notation (BPMN) standards, we devise a systematic procedure for modeling business operations while maintaining confidentiality. While our automation frame- work is robust, certain intricacies of federate behavior necessitate manual adjustments to ensure secure data transmission and protection of proprietary knowledge. The efficacy of our approach, striking a balance between inter- operability and confidentiality in HLA-based simulations, is demonstrated through a comprehensive experiment
LIPTAKOR, a participatory approach for increasing risk awareness and facilitating operational changes at artisanal gold mines
No full textInternational audienceThe literature highlights the importance of engaging local communities when attempting to raise awareness of environmental and human health-related risks at artisanal gold mines. There are, however, few reliable and tested methodologies available to achieve this or which can be adapted for use in a number of contexts. To help bridge this gap, we developed a tangible tool that takes the form of a game, which provides a space for participatory exploration of risk perceptions associated with artisanal gold mining. We present the results of this study, which was conducted in 2021 in the Nigerien Liptako–Gourma Region, and compare them to findings shared in the literature on risk perceptions related to artisanal gold mining
Influence of field retting on physicochemical and biological properties of “Futura 75” hemp stems
No full textInternational audienceThe current development of “Cannabis sativa L.” hemp fibers for technical textiles and biocomposites demands through consideration of the retting process’s effect on fiber quality. Field retting, though crucial, remains insufficiently managed due to its reliance on empirical methods and dependence to weather conditions. This study aims to improve the understanding of the retting process in the case of the “Futura 75” hemp stems harvested at the end of the flowering period and retted in southern France, which is characterized by a dry Mediterranean climate. Various analyses were performed, including color evolution, morphological (optical microscopy), surface (SEM), biological (density of bacterial and fungal community using qPCR approach), and biochemical (solvent extraction and spectro-colorimetry) analyses. The results showed that retting had a major impact on the chemical composition of the fibers, resulting in a significant loss of pectic substances. This result correlated with microscopic observations, which showed the decohesion of fiber bundles during retting. Since an increase in cellulose proportion was observed, this was associated with both the degradation of the non-cellulosic components and an increase in cellulose crystallinity. A color change from green to black during retting, mainly due to microbial colonization was also observed. This result was further supported by the qPCR results, which indicated an increasing presence of bacterial and fungal populations on the hemp stems during the retting process. All the obtained results are statistically analyzed to identify correlations that, in the long term, could eventually lead to the identification of simple indicators to better control the field retting of hemp and obtain stable fiber properties. The statistical findings suggest correlations between variables related to microbial community, pectin degradation, and climatic data throughout the retting process
Faked speech detection with zero prior knowledge
No full textInternational audienceAudio is one of the most used ways of human communication, but at the same time it can be easily misused to trick people. With the revolution of AI, the related technologies are now accessible to almost everyone, thus making it simple for the criminals to commit crimes and forgeries. In this work, we introduce a neural network method to develop a classifier that will blindly classify an input audio as real or mimicked; the word ‘blindly’ refers to the ability to detect mimicked audio without references or real sources. We propose a deep neural network following a sequential model that comprises three hidden layers, with alternating dense and drop out layers. The proposed model was trained on a set of 26 important features extracted from a large dataset of audios to get a classifier that was tested on the same set of features from different audios. The data was extracted from two raw datasets, especially composed for this work; an all English dataset and a mixed dataset (Arabic plus English). For the purpose of comparison, the audios were also classified through human inspection with the subjects being the native speakers. The ensued results were interesting and exhibited formidable accuracy, as we were able to get at least 94 % correct classification of the test cases, as against the 85 % accuracy in the case of human observers
L'économie circulaire utile à tous ? Sa mise en œuvre de l’entreprise jusqu’au territoire
No full textPrésentation des compétences en économie circulaire et projets de recherche menés avec des acteurs socio-économiques de l'Ecole des Mines de Saint-Etienne (Institut Henri Fayol) et de IMT Alès.National audienc
Synthesis and characterization of phosphonic acid functionalized maleic anhydride co-polymer for recovering scandium: Acidic red mud leachate as a case study
No full textInternational audienceA simple one-pot reaction of maleic anhydride with iminodi(methylphosphonic acid) in presence of N,N’-methylenebisacrylamide allows producing a micron-sized multifunctional sorbent (herein called MPOH-MBA, bearing both carboxylate, phosphonate groups, and tertiary amine groups). These multifunctional groups bring high reactivity for rare earth elements (REEs, hard acids) (soft bases O-bearing ligands, consistently with Pearson’s principle) with modulation of positively-charged surface (amine groups for interaction with scandium sulfate species). Effectively, MPOH-MBA shows remarkable sorption capacity for Sc(III) at optimum initial pH (i.e., pH0: 4): qeq,exp reaches up to 5.34 mmol Sc g−1, at room temperature. Langmuir equation fits well experimental profiles (affinity coefficient: 0.677 L mmol−1). Scandium sorption is endothermic: sorption capacity increases up to 6.50 mmol Sc g−1 (at T: 50 °C), while the affinity coefficient increases up to 1.54 L mmol−1. Fast kinetics (equilibrium reached in 20–30 min) are favored by the micron-size of the sorbent (and its good textural properties: 51 m2 g−1 for specific surface area and pore width close to 250 Å). Kinetic profiles are fitted by the pseudo-first order rate equation. The sorbent can be easily regenerated using 0.3 M HCl solution; the loss in sorption is less than 1.5% at the fifth cycle. Main reactive groups (identified by Fourier-transform infrared spectroscopy) are carboxylate and phosphonate groups. In presence of equimolar concentrations of competitor ions: sorption is governed by preference for trivalent metal ions over divalent cations. Among trivalent metal ions rare earth elements (REEs) are preferentially bound (against Al(III) and Fe(III)); in addition, MPOH-MBA sorbs Sc(III) with higher affinity than Nd(III) and Ce(III). The sorbent shows a relative selectivity for scandium and REEs over metal ions present in huge excess (100–500 excess), such as Fe(III) and Al(III)), in red mud acidic leachate
Machine learning for the sensitivity analysis of a model of the cellular uptake of nanoparticles for the treatment of cancer
No full textExperimental studies on the cellular uptake of nanoparticles (NPs), useful for the investigation of NP-based drug delivery systems,are often difficult to interpret due to the large number of parameters that can contribute to the phenomenon. It is therefore of greatinterest to identify unsignificant parameters to reduce the number of variables used for the design of experiments. In this work,a model of the wrapping of elliptical NPs by the cell membrane is used to compare the influence of the aspect ratio of the NP,the membrane tension, the NP-membrane adhesion, and its variation during the interaction with the NP, on the equilibrium stateof the wrapping process. Several surrogate models, such as Kriging, Polynomial Chaos Expansion (PCE), and Artificial NeuralNetworks (ANN) have been built and compared in order to emulate the computationally expensive model. Only the ANN-basedmodel outperformed the other approaches by providing much better predictivity metrics and could therefore be used to compute thesensitivity indices. Our results showed that the NP’s aspect ratio, the initial NP-membrane adhesion, the membrane tension and thedelay for the increase of the NP-membrane adhesion after receptor dynamics are the main contributors to the cellular internalizationof the NP, while the influence of other parameters is negligibl
Facteurs institutionnels et méthodologiques du déploiement de l’APC
No full textInternational audienc
Two‐Step Polyelectrolyte Complex Coating for Flame Retardant Flax
No full textInternational audienceFlax fabric textile is of great interest as bio-fiber reinforcement in composites, which has gained popularity due to the high demand for sustainable materials. Despite its sustainability, flax is inherently flammable. This study demonstrates a two-step polyelectrolyte complex (PEC) coating that renders flax fabric self-extinguishing. The PEC coating consists of polyethylenimine (PEI) and sodium hexametaphosphate (PSP), cured with a citric acid buffer. Sonication employed during the curing process improves the infiltration of the coating into the flax fibers and maintains the fabric's hand. When comparing non-sonicated and sonicated flax samples, the latter achieves self-extinguishing behavior and passes the vertical flame test. Pyrolysis-combustion flow calorimetry reveals that this PEI/PSP coating (with sonication) reduces the peak heat release rate and total heat release by 40% and 67%, respectively. The intumescent mechanism is predominantly observed in the condensed phase, as suggested by differential scanning calorimetry and X-ray photoelectron spectroscopy. The results demonstrate that the two-step PEC treatment with sonication effectively reduces the flammability of flax fabric, making it a promising option for the development of functional fibers, particularly for bio-composite reinforcement
