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Visual charts produced by simulation to correlate service rate, resource utilization and DDMRP parameters
No full textInternational audienceDemand Driven Material Requirements Planning (DDMRP) is a recent method mixing push and pull flow management. Although it claims to be the solution to traditional methods’ limitations, the DDMRP method works at infinite capacity: manufacturing or supply orders are launched according to a logic of replenishment of stocks defined as buffers. This article proposes an evaluation of capacity management using visual charts developed by simulation. These charts correlate the bottleneck resource's loading rate to a service rate by considering one of the DDMRP method parameters, the Decoupled Lead Time (DLT). The charts are a decision support tool. They allow identifying to which loading rate the DLTs are representative of the flow times of manufacturing orders and which capacity level to use. We study different workshops, including a real industrial case. Our results show that it is better to control the flow times by adjusting capacity rather than adjust the DLT parameter
Etude d’une approche d’aide à la décision en gestion de systèmes socio-techniques, basée sur les principes physiques de la mécanique du point et du solide
No full textMaking sound decisions is an inevitable challenge for managing the performance of socio-technical systems. Uncertainty concerning the outcome of decisions leads to seeking principles that systems might follow. The current study leverages and investigates a framework called, "Physics Of Decisions" as an innovative approach for decision support in the context of instability and uncertainty. The focus is on developing a theoretical and mathematical model to depict risks and opportunities as physical forces pushing and pulling investigated systems as an object within a multidimensional performance framework built on the system's evaluation criteria. The main ambition is to define a method of identifying forces, including their origins, intensity, and interdependence, to inherit principles and law from physics. The principles of classical physics are investigated in the defined framework considering mapping management concepts to the physical notations. This connection allows to (i) examine the system's developments in its performance space through kinematic analysis and (ii) provide reactive and predictive decision support as a result of physical forces analysis and its application to the system through force-related physical laws. Investigating the system's behavior under such laws might disclose its compound relationships, thus leading to proper decisions. The foremost objective of this Ph.D. thesis is to establish a generic perspective for performance management of socio-technical systems that visualizes and integrates the impact of risks and opportunities to control the performance of the examined system. Overall, the main intended contribution of this study is to demonstrate the principles of connecting the system to its performance through an innovative modeling framework using different techniques. In further depth, this approach transforms the investigated system and its internal and contextual potentialities from implicit to explicit connection using sensitivity analysis, differential equations, and optimization functions. The significance of this study has been investigated in various application domains: (i) Polling place management, simulated with an Agent-Based Model (ABM), (ii) an epidemic-affected population, simulation with System Dynamics (SD) simulation model, (iii) road traffic management performed with Discrete Event Simulation (DES) model, and (iv) a mathematical model to simulate a manufacturing production model.Prendre des décisions judicieuses est un défi incontournable pour gérer la performance des systèmes sociotechniques. L'incertitude concernant le résultat des décisions conduit à rechercher des principes que les systèmes pourraient suivre. L'étude actuelle exploite et étudie un cadre appelé "Physics of Decision" en tant qu'approche innovante d'aide à la décision dans un contexte d'instabilité et d'incertitude. L'accent est mis sur le développement d'un modèle théorique et mathématique pour décrire les risques et les opportunités en tant que forces physiques poussant et tirant les systèmes étudiés en tant qu'objet dans un cadre de performance multidimensionnel construit sur les critères d'évaluation du système. L'ambition principale est de définir une méthode d'identification des forces, y compris leurs origines, leur intensité et leur interdépendance, pour hériter des principes et des lois de la physique. Les principes de la physique classique sont étudiés dans le cadre défini en tenant compte des concepts de gestion de mappage aux notations physiques. Cette connexion permet (i) d'examiner les développements du système dans son espace de performance grâce à l'analyse cinématique et (ii) de fournir une aide à la décision réactive et prédictive à la suite de l'analyse des forces physiques et de son application au système par le biais de lois physiques liées aux forces. Enquêter sur le comportement du système en vertu de telles lois pourrait révéler ses relations complexes, conduisant ainsi à des décisions appropriées. L'objectif premier de ce doctorat est d'établir une perspective générique pour la gestion de la performance des systèmes socio-techniques qui visualise et intègre l'impact des risques et des opportunités pour contrôler la performance du système examiné. Dans l'ensemble, la principale contribution prévue de cette étude est de démontrer les principes de connexion du système à ses performances grâce à un cadre de modélisation innovant utilisant différentes techniques. Plus en profondeur, cette approche transforme le système étudié et ses potentialités internes et contextuelles d'une connexion implicite à une connexion explicite en utilisant une analyse de sensibilité, des équations différentielles et des fonctions d'optimisation. L'importance de cette étude a été étudiée dans divers domaines d'application : (i) la gestion des bureaux de vote simulée avec un modèle à base d'agents (ABM), (ii) une simulation de population touchée par une épidémie avec le modèle de simulation System Dynamics (SD), (iii ) gestion du trafic routier réalisée avec un modèle de simulation d'événements discrets (DES), et (iv) un modèle mathématique pour simuler un modèle de production manufacturière
A Scenario Generation Method Exploring Uncertainty and Decision Spaces for Robust Strategic Supply Chain Capacity Planning
No full textInternational audienceStrategic Supply Chain Capacity Planning (SSCCP) is an essential activity for companies to prepare their future. However, since uncertainty became an essential factor to consider in this decision-making process, existing solutions to support this process do not fully satisfy their needs anymore. Especially in terms of uncertainty space coverage while exploring and assessing scenarios associated with uncertainty sources and decision options. Therefore, this paper introduces an approach to overcome the complexity of scenario exploration and improve the uncertainty space coverage, to better support SSCCP decision-making. This approach includes a bi-objective metaheuristic that first explores a probability-impact matrix to define a relevant subspace to consider in this uncertainty space, and then uses this subspace to explore the decision space and define a relevant subspace of this decision space to assess and display to decision-makers. Then, an implementation and experiment are described and discussed, and finally avenues for future research are suggested. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG
Integrating Social Media and Business Process Management: Exploring the Role of AI Agents and the Benefits for Agility
No full textInternational audienceBusiness Process Management (BPM) faces increasing societal and business challenges. Societal issues include effectively managing unexpected changes and ensuring employee engagement during process modifications. The former category involves the limitations of technology when introducing process changes while Agile BPM and Social BPM concepts have been explored in previous studies to tackle the latter. These investigations have resulted in the development of a Social-Media (SM) based BPM platform and an agility framework. The SM platform draws inspiration from popular social media platforms such as Twitter and Instagram. Its primary objective is to merge the design-time and run-time phases of the business process (BP) lifecycle as well as to actively engage stakeholders in the dynamic design and implementation of BPs. By simplifying the response to potential changes and maintaining stakeholder involvement throughout the process, the platform addresses the aforementioned challenges. This article establishes a correlation between SM platform concepts and BPM concepts, emphasizing how they facilitate the concurrent design and execution of BPs. Furthermore, the article demonstrates the application of the SM platform in implementing the agility framework through a use case analysis involving a scientific paper submission process. To overcome the current emphasis on stakeholder involvement and human capabilities in applying the platform, we finally explore the possibilities of employing AI agents as automated assistants. © 2024, The Author(s), under exclusive license to Springer Nature Switzerland AG
A Value-Oriented Metamodel for Small and Medium Entreprises Decision Making
No full textInternational audienceTo be competitive and sustainable, any company has to maximize its value. However, unlike listed companies that can assess their values based on market shares, most Small and Medium Enterprises (SMEs) which are non-listed cannot have direct and live access to this critical information. Traditional accounting reports only give limited insights to SME decision-makers about the real impact of their day-to-day decisions on the company’s performance and value. Most of the time, an SME’s financial valuation is made one time a year as the associated process is time and resource-consuming, requiring several months and external expertise to be completed. To solve this issue, we propose in this paper a value-oriented metamodel that enables real-time and dynamic assessment of the SME’s value based on the large definition of their assets. These assets cover a wider scope of resources of the company and better account for immaterial assets. The proposal, which is illustrated in a case study, discusses the benefits of incorporating assets in the SME valuatio
Investment efficiency assessment on the electric grid by group of control
No full text“© 2023 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, including reprinting/republishing this material for advertising or promotional purposes, collecting new collected works for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.”International audienceThe French DSO Enedis spends several hundred million euros every year to maintain and renew its existing network. The investments are made according some policies. One of these policies, called Refurbishment, consists in renovating some segment lines of the overhead medium voltage power network. The choices of the segment lines are made by some experts according mainly to the past outages. To be sure that the choice has been appropriate, we would like to know if the investment is efficient or not. To develop an investment efficiency assessment, we have to compare the number of outages after treatment in a group of refurbished segment lines with a group of un-refurbished segment lines all other things being equal. The method proposed in this paper consist of defining appropriate weights for the un-refurbished segment lines group to make it statistically comparable to the refurbished segment lines group. When we apply the appropriate weights to the unrefurbished segment lines group, we obtain a control group that can be compared to the refurbished segment lines group. By counting the difference of the outages after treatment between the refurbished segment lines group and the control group, we can estimate the performance of the investment. Using the statistical test “Exact Test of Fisher” [2], we can prove that the difference of outages is significant
Supercritical Fluids Technologies for Sustainable Development Goals: Preface
No full textInternational audienc
Influence of silane interfacial chemistry on the curing process of anionic Polyamide 6 in glass reinforced composites
No full textInternational audienceThe manufacturing of composites based on reactive thermoplastic polyamide 6 (PA6), reinforced with glass particles or fibers for structural applications, is quite sensitive to the state of the interface. Surface hydroxyls present at the glass surface can completely inhibit both the PA6 polymerization and crystallization processes. Care must then be exerted when tuning the interfacial chemistry in this system. This work demonstrates how an adequate choice of silane coupling agent, combined with a precise surface grafting methodology and tight control of hydroxyl groups density on glass particulates, yields kinetics and degrees of polymerization and crystallization comparable to the pure PA6 resin. Various silanes were grafted onto the microparticles and their surfaces were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, confocal laser scanning microscopy and contact angle measurements. The activator was also grafted onto the glass surface to initiate polymerization directly from the surface. The results showed that all treated glass particles surfaces allowed obtaining a high degree of conversion but with varying polymerization and crystallization kinetics. The results provide fundamental information on the role of the surface chemistry of glass reinforcements on the polymerization and crystallization of PA6, which are essential for the proper control of composite manufacturing
Situational awareness and decision-making in a crisis situation: A crisis management cell in virtual reality
No full textInternational audienceIn a constantly evolving and hyper-connected world, the crises we are facing are changing, exceeding borders, and impacting every sector of activity. More data can be gathered from the crisis site, arriving in a large flow of various types from multiple sources such as sensors, open data, or social media. This huge amount of data coming continuously from the crisis site leads to an ever-changing situational awareness that must be built and understood as quickly as it is evolving to ensure a relevant and effective crisis response. To build a shared situational awareness, decision-makers can gather in a room where they can share and compare the information they receive from the crisis site to build a common operational picture that they can use to make decisions and implement them: this is a crisis management cell. However, the tools in traditional crisis management cells may not be able to keep up with the new requirements induced by these changes: we need modular and dynamic tools able to adapt to the crisis and the needs of the crisis managers while ensuring collaboration and information sharing not only between the stakeholders but also with remote experts that might be needed to understand the situation. We need to start conceiving the future crisis management cell that would meet the new exigencies of crisis management. This paper proposes our version of that future crisis management cell, using virtual reality to provide a dynamic and modular crisis management cell linked to artificial intelligence and decision-support systems