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Analysis of a Collaborative Resilient Solution Based on Real-Time Re-Optimization for Home Health Care Routes Subject to Disruptions by Discrete Event Simulation
No full text© 2023 IFIP International Federation for Information ProcessingPart 12: Collaborative Networks in Personalized HealthcareInternational audienceHome health care centers face many variations during the execution of routes, compromising initial solution planning. Several studies propose robust solutions to counter small variations, but very few are interested in resilient solutions to counter disruptions. In this paper, we propose a collaborative resilient approach based on real-time re-optimization of caregivers’ routes by considering environmental data at the time the disruption comes out (remaining visits, current position of caregivers, etc.). We analyze and compare this new approach with two others from the literature using discrete event simulation. Our approach reduces the total delay time in most scenarios (by 50% to 90% in the best cases) and outperforms literature approaches in half of the cases. These primary results show that there are many avenues for improvement, such as the development of a better solver or a heuristic and the hybridization between different resilient approaches
Synthesis of novel mesoporous selenium-doped biochar with high-performance sodium diclofenac and reactive orange 16 dye removals
No full textInternational audienceIn this study, for the first time, a selenium-doped mesoporous biochar was prepared and efficiently employed for sodium diclofenac and reactive orange 16 dye adsorption. The characterization results indicated that selenium doping had a remarkable impact on Biochar-Se morphological and physicochemical structures. The efficacy of developed biochar samples on reactive orange 16 (RO-16) and diclofenac (DCF) removals was fully investigated. For both molecules (DCF and RO-16), Liu’s equilibrium model offered the best fitness with maximum adsorption capacity values of 355 mg g-1 for DCF and 538 mg g- 1 for RO-16 for Biochar-Se. Multiple mechanisms including pore filling, π-π interaction, and hydrogen bonding between the Biochar-Se and DCF/RO-16 molecules were involved in the adsorption process. Se-nanoparticles formed metal–oxygen bonds, which boosted the adsorption of DCF and RO-16 molecules. The current work offered a feasible approach for the development of Se-doped biochar adsorbent that is incredibly effective in treating wastewater
A model packing based on a tree of face-to-face regular tetrahedra for monodisperse spheres
No full textInternational audienceThe packing bed of monodisperse spheres is modelled by a tree of face-to-face regular tetrahedra which vertices are the location of the bead's centres. A packing fraction of 0.433 is obtained when this cluster of spheres occupies the maximum space available, without pores large enough to accommodate a new sphere. This value and other structure descriptorscoordination numbers and local packing fraction distributions-are compared with experimental or numerical simulations observations of beds of monodisperse spheres built with different protocols and with capillary or Van-der-Waals forces
Low density polyethylene sachets waste: Fuel conversion, characterization and life cycle analysis
No full textInternational audiencePyrolysis of plastic waste is a practical solution for plastic waste pollution in our environment here in Ghana. Pyrolysis, which is decomposition at high temperatures in the absence of oxygen, enables the conversion of polyethylene (PE) into liquid fuel and flammable gas. The selected pyrolysis temperatures in this study were ~ 300 °C, 350 °C, 400 °C, and 450 °C. Acquired fuels were then analysed via FTIR and GC–MS. These indicated the presence of aromatic compounds, alkenes and peaks of alkanes. The density, cetane index, viscosity at 40 °C, and flash point tests were carried out on each fuel product obtained at the different temperatures. The standardized life cycle assessment methodology according to ISO 14040/44 was carried out to provide a first insight on the savings in Global Warming Potential (GWP) associated to fuel produced from the pyrolysis process compared to that from fossil fuel. Results show a reduction of about 10% in GWP of the PE derived fuel compared to conventional fuel production
Strain localization in Ti and Ti-alloys using three-dimensional topographic imaging
No full textInternational audienceUnderstanding strain localization in titanium and titanium alloys is central to depicting better how individual grains plastically deform and how grain orientation distribution, i.e., the local texture, affects the strain distribution within large regions of interest. High-resolution imaging over large fields of view is vital in detecting the nanometer-scale elementary and irreversible deformation mechanisms as a function of the variability of mesoscopic deformation inherited from the former millimeter-scale β-grains. High Resolution-Digital Image Correlation (HR-DIC) is used to assess quantitative deformation fields from the macroscopic to the microscopic scales. Moreover, HR-DIC is used to identify slip activity in the various polycrystalline Ti and Ti-alloys. Identification of slip systems was obtained using imaging from both scanning electron microscope (SEM) and laser scanning confocal microscope (LSCM). SEM provides a high spatial resolution in the surface plane, while LSCM micrographs provide out-of-plane measurements. Both imaging techniques are complementarily used to identify deformation slip and sliding at the sub-grain scale. In-situ HR-DIC under SEM paired with ex-situ LSCM and conventional SEM observations were used to identify three-dimensional surface strain localization and subsequently slip activity in the various Ti and Ti-alloys under tensile loading at room temperature. Interrupted tensile tests were performed to inform sliding evolution as a function of the applied plastic strain. Both in-plane and out-of-plane sliding displacement were evidenced at the sub-grain level leading to an increase in roughness with increasing applied plastic strain. Interestingly, former β-grains strongly affect both strain distribution and slip activity
Speciation and reaction equilibrium constant modelling of aqueous hydrometallurgical systems at elevated temperatures: A review: review
No full textInternational audienceEncrustation occurs in many processing fluids where high levels of dissolved solids are present, especially in processes that use heat transfer equipment. The deposition of these scales in the interior surfaces of an autoclave can cause major issues in the operation of industrial processes such as hydrometallurgy. The knowledge of the minerals' chemistry, distribution of the chemical forms of these minerals in the autoclave, and their solubility product can assist to inhibit these solid deposits. To model such systems, it is necessary to know the reactions involved and by extension their equilibrium constants. These electrolytic systems being strongly non-ideal, models of activity coefficients are necessary to deduce the concentration of each species. This review presents and compares various models for the calculation of activity coefficients and the thermodynamic equilibrium constants at temperatures above 25 °C. For model validity and comparison purposes, a case study on the speciation of the aqueous binary systems of H 2 SO 4-Al 2 (SO 4) 3 and H 2 SO 4 − MgSO 4 is presented and compared with experimental data. From the results obtained and in the framework presented above, the Density equilibrium constant model coupled with the Truesdell-Jones activity coefficient model gave the best fit with experimental data at the studied temperatures of 235, 250, 270, and 300 °C
Reconfiguration management in manufacturing: A systematic literature review
No full textInternational audienceAufgrund kürzerer Innovations- und Produktlebenszyklen sowie wirtschaftlicher Volatilität steigt der Rekonfigurationsbedarf von Produktionssystemen. Daher wird im Rahmen dieser Arbeit eine systematische Literaturrecherche zum Rekonfigurationsmanagement in der Produktion durchgeführt, um zu ermitteln, inwieweit dies in der Literatur adressiert wird. Dazu wird zunächst eine Definition des Rekonfigurationsmanagements gegeben und zentrale Aspekte rekonfigurierbarer Fertigungssysteme sowie die Defizite der heutigen Rekonfiguration von Fertigungssystemen dargestellt. Aus diesen werden die Anforderungen zur Beantwortung der formulierten Forschungsfrage abgeleitet. Anschließend wird das methodische Vorgehen der Literaturrecherche skizziert, welches auf der Bewertung der abgeleiteten Anforderungen basiert. Abschließend werden die erzielten Ergebnisse dargestellt und weitergehende Erkenntnisse erläutert.Driven by shorter innovation and product life cycles as well as economic volatility, the demand for reconfiguration of production systems is increasing. Thus, a systematic literature review on reconfiguration management in manufacturing is conducted within this work in order to determine by which degree this is addressed by the literature. To approach this, a definition of reconfiguration management is provided and key aspects of reconfigurable manufacturing systems as well as shortcomings of today’s manufacturing systems reconfiguration are depicted. These provide the basis to derive the requirements for answering the formulated research question. Consequently, the methodical procedure of the literature review is outlined, which is based on the assessment of the derived requirements. Finally, the obtained results are provided and noteworthy insights are given
Coupling radiative, conductive and convective heat-transfers in a single Monte Carlo algorithm: A general theoretical framework for linear situations
No full textInternational audienceIt was recently shown that radiation, conduction and convection can be combined within a single Monte Carlo algorithm and that such an algorithm immediately benefits from state-of-the-art computer-graphics advances when dealing with complex geometries. The theoretical foundations that make this coupling possible are fully exposed for the first time, supporting the intuitive pictures of continuous thermal paths that run through the different physics at work. First, the theoretical frameworks of propagators and Green’s functions are used to demonstrate that a coupled model involving different physical phenomena can be probabilized. Second, they are extended and made operational using the Feynman-Kac theory and stochastic processes. Finally, the theoretical framework is supported by a new proposal for an approximation of coupled Brownian trajectories compatible with the algorithmic design required by ray-tracing acceleration techniques in highly refined geometry
Projet RéSoCIO : Analyse des réseaux sociaux en situation d’urgence
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