Publications

20/06/2024

The industrial management of SMEs in the era of Industry 4.0

Auteurs : MOEUF, Alexandre PELLERIN, Robert LAMOURI, Samir TAMAYO, Simon BARBARAY, Rodolphe
Publisher : Taylor et Francis
Industry 4.0 provides new paradigms for the industrial management of SMEs. Supported by a growing number of new technologies, this concept appears more flexible and less expensive than traditional enterprise information systems such as ERP and MES. However, SMEs find themselves ill-equipped to face these new possibilities regarding their production planning and control functions. This paper presents a literature review of existing applied research covering different Industry 4.0 issues with regard to SMEs. Papers are classified according to a new framework which allows identification of the targeted performance objectives, the required managerial capacities and the selected group of technologies for each selected case. Our results show that SMEs do not exploit all the resources for implementing Industry 4.0 and often limit themselves to the adoption of Cloud Computing and the Internet of Things. Likewise, SMEs seem to have adopted Industry 4.0 concepts only for monitoring industrial processes and there is still absence of real applications in the field of production planning. Finally, our literature review shows that reported Industry 4.0 projects in SMEs remained cost-driven initiatives and there in still no evidence of real business model transformation at this time.
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12/06/2024

Adaptive System to Enhance Operator Engagement during Smart Manufacturing Work

Auteurs : PASSALACQUA, Mario JOBLOT, Laurent MAGNANI, Florian PELLERIN, Robert LEGER, Pierre-Majorique
Publisher :
Sustaining optimal task engagement is becoming vital in smart factories, where manufacturing operators' roles are increasingly shifting from hands-on machinery tasks to supervising complex automated systems. However, because monitoring tasks are inherently less engaging than manual operation tasks, operators may have a growing difficulty in keeping the optimal levels of engagement required to detect system errors in highly automated environments. Addressing this issue, we created an adaptive task engagement feedback system designed to enhance manufacturing operators’ engagement while working with highly automated systems. Utilizing real-time acceleration, heart rate, and respiration rate data, our system provides an intuitive visual representation of an operator's engagement level through a color gradient, ensuring operators can stay informed of their engagement levels in real-time and make prompt adjustments if required. This article elaborates on the six-step process that guided the development of this adaptive feedback system. We developed a task engagement index by leveraging the physiological distinctions between more and less engaging manufacturing scenarios and using automation to induce lower engagement. This index demonstrates a prediction accuracy rate of 80.95 % for engagement levels, as demonstrated by a logistic regression model employing leave-one-out cross-validation. The implications of deploying this adaptive system include enhanced operator engagement, higher productivity and improved safety measures.
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12/06/2024

Avatars in Immersive Virtual Reality Education: Preliminary Insights and Recommendations from a Systematic Review

Auteurs : MIGUEL-ALONSO, Ines MAYER, Anjela CHARDONNET, Jean-Rémy BUSTILLO, Andres OVTCHAROVA, Jivka
Publisher : Springer Nature Switzerland
Immersive Virtual Reality (iVR) has gained popularity in education for its ability to engage students and enhance learning. With the growing use of avatars in collaborative iVR environments, there is a need for structured guidelines to optimize their effectiveness. This preliminary systematic literature review aims to synthesize key findings from relevant studies, investigates the potential of avatars in iVR education and proposes best practices to promote positive learning outcomes. Gathering data from various studies, the review provides initial insights that will aid future researchers and developers in effectively integrating iVR and avatars, optimizing them for the educational setting, and ensuring their effectiveness in enhancing learning outcomes.
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07/06/2024

Flow modeling and structural characterization in fungal pellets

Auteurs : SÁNCHEZ-VARGAS, J. VALDÉS-PARADA, F.J. PERAZA-REYES, L. DIDIER, LASSEUX TRUJILLO-ROLDÁN, M.A.
Publisher : Elsevier BV
Fungal pellets are hierarchical systems that can be found in an ample variety of applications. Modeling transport phenomena in this type of systems is a challenging but necessary task to provide knowledge-based processes that improve the outcome of their biotechnological applications. In this work, an upscaled model for total mass and momentum transport in fungal pellets is implemented and analyzed, using elements of the volume averaging and adjoint homogenization methods departing from the governing equations at the microscale in the intracellular and extracellular phases. The biomass is assumed to be composed of a non-Newtonian fluid and the organelles impervious to momentum transport are modeled as a rigid solid phase. The upscaled equations contain effective-medium coefficients, which are predicted from the solution of adjoint closure problems in a three-dimensional periodic domains representative of the microstructure. The construction of these domains was performed for Laccaria trichodermophora based on observations of actual biological structures. The upscaled model was validated with direct numerical simulations in homogeneous portions of the pellets core. It is shown that no significant differences are observed when the dolipores are open or closed to fluid flow. By comparing the predictions of the average velocity in the extracellular phase resulting from the upscaled model with those from the classical Darcy equation (i.e., assuming that the biomass is a solid phase) the contribution of the intracellular fluid phase was evidenced. This work sets the foundations for further studies dedicated to transport phenomena in this type of systems.
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07/06/2024

Non local multiaxial fatigue modeling of defects: A unified approach to interpret size and shape effects

Auteurs : MEROT, Pierre MOREL, Franck ROBERT, Camille PESSARD, Etienne GALLEGOS MAYORGA, Linamaria BUTTIN, Paul
Publisher :
This paper deals with the effect of defect size and shape under high cycle fatigue for metallic alloys. A large simulation campaign based on a multiaxial fatigue criterion and a non-local approach is presented. A relative defect size based on a ratio between the defect size and a characteristic length introduced by the non-local approach is defined. A normalized Kitagawa–Takahashi diagram is then obtained. A competition between the highly stressed volume size and the local maxima due to the defect is observed and seem dependent on the relative defect size. The effect of the loading mode (uniaxial and pure shear) and of the plasticity are discussed. Finally, a comparison of the simulation results with experimental data on a 316L L-PBF demonstrates the robustness of the proposed approach and explains the negligible effect of the defect morphology compared to its size.
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06/06/2024

Paediatric skull growth models: A systematic review of applications to normal skulls and craniosynostoses

Auteurs : GEOFFROY, Maya FRANÇOIS, Pierre-Marc KHONSARI, Roman Hossein LAPORTE, Sébastien
Publisher :
Introduction Craniosynostoses affect 1/2000 births and their incidence is currently increasing. Without surgery, craniosynostosis can lead to neurological issues due to restrained brain growth and social stigma due to abnormal head shapes. Understanding growth patterns is essential to develop surgical planning approaches and predict short- and long-term post-operative results. Here we provide a systematic review of normal and pathological cranial vault growth models. Material and Methods The systematic review of the literature identified descriptive and comprehensive skull growth models with the following criteria: full text articles dedicated to the skull vault of children under 2 years of age, without focus on molecular and cellular mechanisms. Models were analysed based on initial geometry, numerical method, age determination method and validation process. Results A total of 14 articles including 17 models was reviewed. Four descriptive models were assessed, including 3 models using statistical analyses and 1 based on deformational methods. Thirteen comprehensive models were assessed including 7 finite element models and 6 diffusion models. Results from the current literature showed that successful models combined analyses of cranial vault shape and suture bone formation. Discussion Growth modelling is central when assessing craniofacial architecture in young patients and will be a key factor in the development of future customized treatment strategies. Recurrent technical difficulties were encountered by most authors when generalizing a specific craniosynostosis model to all types of craniosynostoses, when assessing the role of the brain and when attempting to relate the age with different stages of growth.
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05/06/2024

Integration of additive manufacturing and augmented reality in early design phases: a way to foster remote creativity

Auteurs : CUI, Jinxue LOU, Ruding MANTELET, Fabrice SEGONDS, Frédéric
Publisher : Springer Science and Business Media LLC
Additive Manufacturing (AM) has known a substantial growth in recent years. More and more designers are interested in using AM during the early design stages, and are not familiar with the opportunities provided by AM. Augmented Design with AM Methodology (ADAM2) is a methodology which can help the designer to understand and exploit the potential of AM. This methodology can be explained through inspirational objects to represent the opportunities of AM. However, due to the substantial manufacturing expenses incurred in producing multiple sets of physical cubes of ADAM2 during the product design process, this paper exploring the implementation of Augmented Reality (AR) technology as a cost-effective means to showcase and demonstrate these cubes. This paper presents the integration of 14 cubes and AR and evaluates whether virtual cubes could have similar performance as real cubes in terms of usability and AM potential. The digitalization of these inspirational objects and their inter-action through AR is proposed to overcome the limits of physical objects during early product design. Through a mobile device (e.g., smartphone) the user can interact through screen with virtual inspirational objects. An AR application is developed to let users have interaction with 14 virtual cubes as similar with manipulating with real cubes. Users could manipulate cubes and change their material with the markerless AR application. Then the prototyped AR application is tested by experiment. The result shows the virtual cubes can achieved promising performance as similar as the real cubes in the usability and demonstrating the potential of AM. In future work, experiments will be conducted to examine the impact of early design on creativity.
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05/06/2024

Modeling of muscular activation of the muscle-tendon complex using discrete element method

Auteurs : ROUX, Anthony LECOMPTE, Jennyfer IORDANOFF, Ivan LAPORTE, Sébastien
Publisher : Taylor & Francis
The tearing of a muscle-tendon complex (MTC) is caused by an eccentric contraction; however, the structures involved and the mechanisms of rupture are not clearly identified. The passive mechanical behavior the MTC has already been modeled and validated with the discrete element method. The muscular activation is the next needed step. The aim of this study is to model the muscle fiber activation and the muscular activation of the MTC to validate their active mechanical behaviors. Each point of the force/length relationship of the MTC (using a parabolic law for the force/length relationship of muscle fibers) is obtained with two steps: 1) a passive tensile (or contractile) test until the desired elongation is reached and 2) fiber activation during a position holding that can be managed thanks to the Discrete Element model. The muscular activation is controlled by the activation of muscle fiber. The global force/length relationship of a single fiber and of the complete MTC during muscular activation is in agreement with literature. The influence of the external shape of the structure and the pennation angle are also investigated. Results show that the different constituents of the MTC (extracellular matrix, tendon), and the geometry, play an important role during the muscular activation and enable to decrease the maximal isometric force of the MTC. Moreover, the maximal isometric force decreases when the pennation angle increases. Further studies will combine muscular activation with a stretching of the MTC, until rupture, in order to numerically reproduce the tearing of the MTC.
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03/06/2024

Temperature-dependent structural and magnetic properties of mechanically alloyed Ni80Co17Mo3 powder mixture

Auteurs : RAFAI, H. SMILI, B. SAKHER, E. SAKMECHE, M. CHADLI, S TIGRINE, R. PESCI, Raphaël BOUOUDINA, M. SAKMECHE, M. BELLUCCI, S.
Publisher : ELSEVIER
Nanostructured materials containing nickel improve the effectiveness of several applications. This study examines the preparation and characterization of nanostructured Ni80Co17Mo3 alloy powders using high-energy mechanical alloying and subsequent annealing. A 72 h milling process used pure elemental powders to synthesise nanocrystalline FCC-NiCo(Mo) solid solution. The milled powders were then subjected to annealing at different temperatures:300◦C, 500◦C, and 750◦C. X-ray diffraction, scanning electron microscopy coupled with energy-dispersive spectroscopy, and vibrating sample magnetometry indicated significant changes in the powdered alloy properties. The particles growth occurred as the annealing temperature increased, while the microstrain decreased significantly; 14.30±0.07 nm up to 56.30±0.28 nm and 0.680±0.003 % up to 0.180 ±0.001 %, at 25◦C and 750◦C respectively. SEM analysis revealed differences in particle size and shape as milling progressed. Surprisingly, the milled powdered alloy displayed improved magnetic properties, manifesting significant magnetic susceptibility and enhanced saturation magnetisation, remanent magnetisation, and coercivity within the temperature range of 300◦C to 750◦C. These findings indicate the development of a consistent and structured state, accompanied by significant crystal growth due to the annealing temperature. This study highlights the great importance of high-energy mechanical milling and subsequent annealing to tune / tailor the characteristics and subsequently investigate the potential utilization of nanostructured Ni-based alloys.
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03/06/2024

Comparison of reduced basis construction methods for Model Order Reduction, with application to non-linear low frequency electromagnetics

Auteurs : HENNERON, Thomas CLENET, Stephane FRATILA, M. DUCREUX, J.P.
Publisher : Elsevier BV
Numerical simulation is more and more used during the design stage of a manufactured product in order to optimize its performances. However, it is often too time consuming, particularly when it’s used to solve optimization problems, preventing an intensive usage. A-posteriori Model Order Reduction methods can be very effective to shorten the computational time. An approximated solution is then sought in a space of small dimension defined by a reduced basis. The accuracy of such methods is highly dependent on the choice of the reduced basis, extracted from preliminary numerical simulation. The method usually applied to construct such reduced basis is based on the Singular Value Decomposition (SVD), which can be time consuming, and is not adapted when a large collection of preliminary numerical simulations must be used to construct the basis. An alternative to this approach has been proposed recently with the Maximum Entropy Snapshot Sampling (MESS) method. In this paper, we propose to compare these methods with other approaches usually used for clustering or data classification based on vectors distance calculation, like the Centroidal Voronoi Tessellation (CVT), Density Based Spatial Clustering of Applications with Noise (DBSCAN), and Clustering Using Representatives (CURE). The methods are compared on a complex and realistic nonlinear problem in low frequency electromagnetics. The quality of the reduced bases obtained by the different methods are compared. Then, field distributions and global quantities, like eddy current losses and magnetic energy, are computed from the reconstructed results, to further analyze the quality of the reduced bases.
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