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Digital Twin in Healthcare: Security Threat Meta-Model
No full text"© 2023 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.”International audienceA virtual mirrored replica of the real-world, has become a new trend in recent years with the advent of Industry 4.0, shows how intelligent digital twins (DT) can unlock busi-ness value. The implementation of DT requires various types of technologies, including the Internet of Things (IoT), cloud computing, artificial intelligence, and others. Today, DTs can be used in various fields, including manufacturing, smart cities and healthcare. It can be used to monitor the real environment, predict its future, control its behavior, and improve its overall performance. Despite the aforementioned advantages of DTs, if not protected, they can also be considered as an open environment for attackers. If attackers take over a DT, they may end up owning the real environment controlled by the DT. This can result in damaging consequences. This paper explores the potential security and privacy threats that may be brought in through DTs. It proposes and presents a threat meta-model of DTs that identifies key security aspects of concern
Calcium as an innovative and effective catalyst for the synthesis of graphene-like materials from cellulose
No full textInternational audiencePyrolysis of lignocellulosic biomass (hard carbon) produces poorly graphitic biochar. In this study, nano-structured biochars were produced from microcrystalline cellulose using calcium as a non-conventional catalyst. Calcium is abundant, environmental-friendly and widely accessible. Graphitization of calcium-impregnated cellulose was carried out at 1800 °C, a temperature below 2000 °C where the graphitization usually occurs. XRD, Raman spectroscopy, high-resolution TEM together with the in-house numerical tool developed enable the quantification of the graphene fringes in the biochars. The non-impregnated cellulose biochar was composed of short and poorly stacked graphene fringes. The impregnation with 2 wt.% of calcium led to the conversion of the initial structure into a well-organized and less defective graphene-like one. The graphene-like structures obtained were composed of tens of stacked graphene fringes with a crystallite size up to 20 nm and an average interlayer spacing equal to 0.345 nm, close to the reference value of standard hexagonal graphite (0.3354 nm). The increase of the calcium concentration did not significantly improve the crystallite sizes of the graphene-like materials but rather drastically improved their rate. Our results propose a mechanism and provide new insights on the synthesis of graphene-like materials from bio-feedstocks using calcium where the literature is focused on transition metals such as iron and nickel among others. The decrease of the graphitization temperature below 2000 °C should lower the production cost as well as the environmental impact of the thermal graphene-like materials synthesis using biomass. This finding should stimulate further research in the field and broaden the application perspectives
Preparation and characterization of cationic pullulan-based polymers with hydrophilic or amphiphilic characteristics for drug delivery
No full textInternational audiencePullulan has attracted considerable attention due to its immunogenicity, biodegradability, biocompatibility, and hydrophilic nature, making it useful in cosmetics and pharmaceutical applications. In addition, pullulan is considered a biopolymer capable of modification via chemical reactions, which is a promising strategy to expand the range of its applications. In this study, cationic pullulan-based polymers with hydrophilic or amphiphilic nature were successfully synthesized by nucleophilic replacement and ring-opening polymerization. Firstly, pullulan was partially modified with 2-Chloro-N,N-diethylethylamine (DEAE) to generate DEAE-modified pullulan (PULL-DEAE), a polymer with cationic and hydrophilic nature. Secondly, the remaining hydroxyl groups of PULL-DEAE were reacted with N-carbobenzyloxy-l-lysine N-carboxyanhydride (Lys(Z)-NCA), producing the grafted copolymer pullulan-DEAE-g-poly(Z-l-lysine) (PULL-DEAE-g-PZLL), a copolymer with cationic and amphiphilic properties. For the copolymerizations, different monomer concentrations (25, 40, and 55% w/w, relating to pullulan) were used, resulting in three copolymers with different sizes of hydrophobic segments. All polymers were characterized in terms of chemical composition, molar mass, thermal properties, critical aggregation concentration, and cytotoxicity. NMR confirmed the graft copolymerization, and the degree of substitution obtained for each copolymer was 0.13, 0.54, and 0.63, respectively. The results suggest that the physicochemical properties of both pullulan-based cationic derivatives (PULL-DEAE and PULL-DEAE-g-PZLL) could expand the application of modified pullulan for pharmaceutical fields such as drug delivery
Assessing the Business Continuity of a healthcare organization through a data-gathering modality approach
No full text"© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.”International audienceMost business continuity planning methods help provide adequate precautions in case of a crisis situation to keep the organization’s main activities running uninterruptedly in the moment of the crisis. One way to accurately improve the rules that arise from business continuity planning (BCP) would be to (i) proceed with the data multidimensions and multi-sources (physical, societal, financial, etc.) through a purpose-driven Information System (IS), (ii) build customized integral robustness indicators and (iii) use them to qualify the business continuity strategy. On this basis, this work’s findings make firms, particularly healthcare organizations, less sensitive to catastrophes by designing an interactive dashboard that pilots the business continuity indicators and highlights decisive components and resources
Using Social Media Data in Emergency Management: A Proposal for a Socio-Technical Framework and a Systematic Literature Review
No full textInternational audienceData represents an essential resource to the management of emergencies: organizations have been growingly investing in technologies and resources to lever data as an asset before, during, and after disasters and emergencies. However, research on data usage in emergency management remains fragmented, preventing practitioners and scholars from approaching data comprehensively. To address this gap, this research in progress consists of a systematic review of the literature in a two-steps approach: we first propose a socio-technical framework and use it in an exploratory mapping of the main topics covered by the literature. Our preliminary findings suggest that research on data usage primarily focuses on technological opportunities and affordances and, hence, lacks practical implementation aspects in organizations. The expected contribution is double. First, we contribute to a more comprehensive understanding of data usage in emergency management. Second, we propose future avenues for research on data and resilience
Managing supply chains during the Covid-19 crisis: synthesis of academic and practitioner visions and recommendations for the future
No full textInternational audiencePurpose The Covid-19 pandemic has created an environment of high uncertainty and caused major disruptions in supply chains. The new normal that has emerged during the pandemic is leading to a need to identify new solutions to improve supply chain crisis management in the future. Practitioners require adapted recommendations for solutions to implement. These recommendations are laid out in this paper. Design/methodology/approach A combination of a systematic literature review (SLR), qualitative semi-structured interviews and a questionnaire survey of supply chain practitioners is applied. The interviews provide insights into supply chain practitioners' views of their approaches and, together with the solutions proposed in the literature, provide future recommendations for action for supply chain managers. Findings During the pandemic, companies experienced disruptions in supply, production and demand, as well as interruptions in transportation and distribution. The majority of the solutions proposed in the literature, coincide with the opinions of practitioners. These include collaborative risk management, real-time monitoring and information sharing, supply network management, scenario planning and “what-if” simulations. Research limitations/implications Although the number of interviews conducted and questionnaires completed is limited, they still serve to supplement the SLR with important practical insights and recommendations. Originality/value This paper presents a review of recent academic literature focusing on the impact of Covid-19 on supply chains and the existing solutions to mitigate that impact and manage future crises. It has been expanded to include industry perspectives and experiences. The findings of this study present recommended practices and strategies for better managing supply chains during a crisis
Multi-scale analysis of the damage and contamination in abrasive water jet drilling of GLARE fibre metal laminates
No full textInternational audienceThe goal of this study is to investigate the influence of Abrasive Water Jet (AWJ) parameters (standoff distance, water pressure and abrasive flow rate) on the machining quality (diameter, circularity, abrasive contamination, surface roughness and types of damage) during drilling of thick hybrid material viz. GLARE (Glass Laminate Aluminium Reinforced Epoxy) Fibre Metal Laminates (FML). The novelty of this work is the use of X-ray tomography and image post-processing for the quantification of abrasive contamination in function of the machining parameters. Moreover, the indicator called 'power of erosion' (E), depending on the AWJ drilling parameters chosen, has permitted to estimate a threshold below which no delamination is found. The results have shown that oversized holes (up to 6.2 mm in diameter) were produced under all cutting parameters regardless of their level. Increasing the standoff distance increased the hole size and cylindricity. The main types of damage consecutive AWJ drilling are in form of barrelling at plies level and delamination with embedded particles. For 'power of erosion' (E) values below 0.17, no delamination is found. As increasing this indicator further, delamination occurs in-between plies closer to the jet entry and more contamination is observed (up to 4 % of the total scanned surface). The surface roughness was found to be in a similar range to that reported in conventional drilling studies of GLARE (<6 μm), which suggests that AWJC could provide a similar machining performance suitable for aerospace applications
Nickel nanoparticles immobilized on pristine halloysite: an outstanding catalyst for hydrogenation processes
No full textInternational audienceNickel nanoparticles (NiNPs) immobilized on halloysite-based supports were straightforwardly synthesized and fully characterized by different techniques with the purpose of evaluating the catalytic performance of these as-prepared composite materials as catalysts in hydrogenation reactions. Thus, halloysite bearing amino (HAL-NH 2 ) and ammonium (HAL-NEt 3 ) groups led to less active catalytic materials in comparison with unfunctionalized halloysite supports, probably due to relative strong metal-support interactions with amino and tetraalkylammonium functions, consequently hindering the interaction of unsaturated substrates at the surface of the catalytic material. Despite NiNPs supported on pristine halloysite provided merely agglomerates, NiNPs stabilized by quinidine on unfunctionalized halloysite ( NiC ) proved to be a highly effective and versatile catalyst operating at relative low temperature (25-100 °C) and metal loading (1-20 mol%Ni), very well-adapted to reduce a large range of functions (alkenes, alkynes, ketones, aldehydes, nitro…). Moreover, NiC was able to selectively reduce substrates from biomass to yield high value-added products, such as squalane, saturated fatty acids, furfuryl alcohol and gamma -valerolactone
A Decision Support System for Better Qualitative Supply Chain Diagnoses
No full textPart 11: Agile and Responsive Supply ChainsInternational audienceIn the current supply chain world where instability and variability are the norm, being able to efficiently identify/diagnose the root causes of non-performance is of prime importance. Although numerous methods exist to support quantitative diagnosis step, there are very few materials regarding the qualitative dimension of diagnosis. Additionally, the rare existing methods are very time-intensive, need scarce expertise and often produce poor results. In a such context, the problem is how to make supply chain qualitative diagnoses impactful and fast. Practically, this paper develops a business process and its associated knowledge-based system, inspired by the theory of constraints’ thinking processes approach, to effectively support practitioners in their qualitative diagnosis step. A set of real industrial application cases is analyzed to discuss the implications of the contribution. It notably demonstrates that the proposal supports both increasing the impact of the diagnosis and reducing the time of the process by almost 80%
Pyrolyse et gazéification d'un combustible solide de récupération (CSR) et de ses matériaux modèles
No full textSolid waste materials that cannot be reused or recycled are increasingly used to produce Solid Recovered Fuels (SRF). They can be transformed by thermochemical processes such as gasification, thus producing a synthesis gas that can be used in cogeneration (heat and electricity) or for the synthesis of liquid or gaseous fuels. SRF constitute a raw material of interest, that has been largely less studied than biomass in gasification. The objective of the thesis is to investigate the pyrolysis and gasification of SRF, in relation with their physical and chemical characteristics, under controlled operating conditions. For this purpose, a new laboratory-scale experimental device was developed. An experimental characterization and CFD calculations provided a complete description of the temperature profiles for the sample and the gas inside the reactor. Several model materials (wood, cardboard, polyethylene terephthalate, polyethylene and polypropylene), often found in SRF, were studied separately, in an inert atmosphere and in the presence of air as an oxidizing agent. The yield and distribution of reaction products (char, gas species, tar) were determined. Pyrolysis of wood/plastic mixtures showed an increased conversion of carbon to gaseous products in comparison with what would be expected with no interaction. Based on the experimental pyrolysis results for the individual model materials, a correlation was developed to predict the product yields as a function of the feedstock C, H and O contents.Certains déchets solides qui ne peuvent être ni réutilisés ni recyclés sont de plus en plus utilisés dans la production de Combustibles Solides de Récupération (CSR). Ils peuvent être valorisés par des procédés thermochimiques comme la gazéification, produisant ainsi un gaz de synthèse utilisable en cogénération (chaleur et électricité) ou pour la synthèse de carburants liquides ou gazeux. Les CSR constituent une matière première d'intérêt, qui a cependant été largement moins étudiée que la biomasse en gazéification. L'objectif de la thèse est d'étudier la pyrolyse et la gazéification de CSR, en lien avec leurs caractéristiques physiques et chimiques, dans des conditions opératoires contrôlées. Pour cela, un nouveau dispositif expérimental à l'échelle du laboratoire a été développé. Une caractérisation expérimentale et des calculs CFD ont fourni une description complète des profils de température pour l'échantillon et le gaz à l'intérieur du réacteur. Plusieurs matériaux modèles (bois, carton, polyéthylène téréphtalate, polyéthylène et polypropylène), souvent présents dans les CSR, ont été étudiés séparément, en atmosphère inerte et en présence d'air en tant qu'agent oxydant. Le rendement et la distribution des produits de réaction (résidu carboné, espèces gazeuses, goudrons) ont été déterminés. La pyrolyse des mélanges bois/plastique a montré une conversion accrue du carbone en produits gazeux en comparaison à ce qui aurait été attendu sans interaction. En se basant sur les résultats expérimentaux de pyrolyse pour les matériaux modèles, une corrélation a été développée dans le but de prévoir les rendements de pyrolyse à partir des fractions massiques en C, H et O des ressources