Dynamic mutual adjustment search for supply chain operations planning coordination

RÉSUMÉ Les chaînes d’approvisionnement sont des systèmes complexes comprenant plusieurs organisations indépendantes avec des objectifs différents dans un environnement incertain et dynamique. Une question clé dans la gestion de chaîne d’approvisionnement (Supply Chain Management) est la coordination des décisions de planification des opérations. Les systèmes de planification de chaîne d’approvisionnement introduits dans la littérature peuvent être classés en deux systèmes de planification principaux: les systèmes de planification centralisés et les systèmes de planification décentralisés. Les systèmes centralisés peuvent théoriquement optimiser les performances de la chaîne d’approvisionnement bien que leur mise en œuvre nécessite un haut degré d’échange d’informations entre les partenaires de la chaîne d’approvisionnement. Cela conduit à des difficultés lorsque des partenaires indépendants ne veulent pas partager l’information. Afin de répondre à ces difficultés, les systèmes décentralisés de planification des opérations sont conçus dans lesquels chaque membre est une entité économique distincte qui prend ses décisions opérationnelles de manière indépendante, mais avec un niveau minimal d’échange d’information. Dans cette thèse, nous étudions dans un premier temps les méthodes de coordination des processus de planification des opérations dans les chaînes d’approvisionnement proposées dans la littérature. Ensuite, nous proposons un cadre de classification de ces méthodes basée sur la technologie mise en œuvre, et identifions des opportunités de recherches. Dans un deuxième temps, nous proposons une approche de coordination décentralisée qui consiste en un ajustement mutuel des décisions de planification basé sur la programmation mathématique et l’échange d’incitatifs financiers. Ce mécanisme, contrairement à un système centralisé traditionnel, implique deux entreprises, qui interagissent l’une avec l’autre afin d’améliorer leur performance. Dans le cadre de cette approche, seul un petit sous ensemble des solutions de coordination sont considérées, et l’expérimentation montre que cette approche de coordination a un potentiel d’amélioration du profit global tout en préservant l’équité en termes de partage des bénéfices de l’amélioration. Enfin, afin de proposer une méthode de coordination capable d’être utilisable dans le contexte dynamique des chaînes d’approvisionnement, cette thèse propose dans un premier temps une stratégie performante de négociation du fournisseur adaptée à l’approche de coordination proposée, ainsi qu’une stratégie de partage des revenus appliquée à un contexte d’horizon roulant. L’analyse de la performance de cette méthode particulière montre également que l’approche proposée produit une stratégie gagnante-gagnante pour les deux partenaires de la chaîne d’approvisionnement et améliore les résultats de planification.----------ABSTRACT Supply chains are complex systems, which include several independent organizations with different objectives, in dynamic uncertain environment. A key issue in supply chain management (SCM) is the coordination of supply chain operations planning decisions. Supply chain planning systems introduced in the literature can be classified into two main planning systems: centralized and decentralized planning systems. Centralized systems can theoretically optimize supply chain performance although its implementation requires a high degree of information exchange among supply chain partners. This leads to difficulties when independent partners do not want to share information. In order to address these difficulties, decentralized systems are designed for supply chains where each member is a separate economic entity that makes its operational decisions independently, yet with some minimal level of information sharing. In this thesis, we first review supply chain operations planning coordination methods from centralized to decentralized approaches proposed in the literature. Next, we propose a classification scheme of these approaches based on the technology used by the authors. Finally, we identify research opportunities. Second, we propose a decentralized operations planning coordination mechanism referred to as mutual adjustment search (MAS), which is based on a negotiation-like mutual adjustment of planning decisions with financial incentives and rooted in mathematical programming. This mechanism, unlike traditional centralized system, involves two independent enterprises linked by material and non-strategic information flows, which interact with each other in order to coordinate their operations planning, and to improve their individual and collective performance. In this approach, only a few coordination solutions (pairs of coordinated operations plans) are considered and computational analysis shows that this coordination mechanism has the potential to improve global profit, while maintaining fairness in terms of revenue sharing. Finally, in order to develop an approach capable of supporting the dynamic coordination of operations planning in a rolling horizon context, this thesis first proposes a negotiation strategy for the supplier, as well as a revenue sharing protocol. Computational analysis shows that the proposed approach produces a win-win strategy for two partners of supply chain and improves the results of upstream planning

Analyse des déterminants de la performance des équipes de projets dispersées: prise en compte de l’influence décisionnelle de trois groupes d’acteurs

RÉSUMÉ Bon nombre de projets technologiques actuels sont réalisés par des équipes de projets dispersées géographiquement. Des phénomènes, comme la mondialisation de l’économie et le développement fulgurant des technologies de l’information et des communications, sont autant de facteurs qui ont permis l’émergence de ce type de fonctionnement. Responsables de projets et experts techniques se trouvent donc souvent dans un contexte où les rapports intraéquipes se trouvent modifiés; planification du travail, répartition des rôles, mobilisation des membres et résolutions de conflits sont des exemples d’actes de gestion qu’il faut adapter en fonction de ce nouveau contexte. Dans le cadre de ce mémoire, ce sont les processus décisionnels qui sont au coeur de la problématique. Plus spécifiquement, le mémoire s’inscrit dans le courant actuel des facteurs de succès et de la performance des équipes dispersées, et tient compte de l’influence décisionnelle que peuvent avoir certains groupes d’acteurs projets. Nous avons testé des hypothèses quant aux liens pouvant exister entre certaines dimensions et la performance des équipes. Après avoir fait un état des connaissances des concepts liés à la prise de décision et aux équipes dispersées, nous avons exploité une base de données montée à l’aide d’un questionnaire en ligne. Ce questionnaire fut expédié à 1 000 professionnels travaillant en équipes dispersées et basés au Québec, et nous a permis de récupérer un total de 149 questionnaires exploitables.----------ABSTRACT Technology projects today are increasingly handled by distributed teams with members spread around the world. Globalization and the rapid development of information and communication technologies (ICT) are mainly responsible for the rise in distributed teamwork and virtual teams. Project managers and technical experts must cope with a new environment in which team relationships are differently defined. task planning and allocation, team motivation, and conflict solving must be adapted to this new context. In this research, we focused on the decisional process in virtual teams. More specifically, we examined the dynamic interplay between success factors, performance indicators, and the decisional influences of three categories of actors. We tested several hypotheses to evaluate the relationships between various dimensions and virtual team performance. Following a literature review on decision-making concepts and virtual teams, we used a data bank built from an online survey. A questionnaire was sent to a thousand Quebec-based professionals working in virtual teams, resulting in 149 respondents. We first characterized virtual teams by the influential relationships within them, in terms of three actor groups: project managers, team members, and top management. We then performed clustering on the thirty questionnaire items about decisional influences and identified three decisional patterns: small teams with high autonomy (cluster 1), strongly structured organizations (cluster 3), and ad-hoc organizations (cluster 2). To better understand these clusters, we conducted mean comparisons of dimensions

A multi-agent system for a bus crew rescheduling system

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Unpredictable events (UE) are major factors that cause disruption to everyday bus operation. In the occurrence of UE, the main resources - crews and vehicles - are affected, and this leads to crew schedule disruption. One way to deal with the problem is crew rescheduling. Most of the current approaches are based on static schedules do not support rescheduling in a real-time scenario. They have the ability to reschedule but a new complete schedule is produced without concerning the real time situation. The mathematical approaches which are used by most scheduling packages have the ability to search for optimum or near optimum schedules but they are usually slow to produce results in real-time because they are computationally intensive when faced with complex situations. In practice, crew or bus rescheduling is managed manually, based on the supervisor's capabilities and experience in managing UE. However, manual rescheduling is complex, prone to error and not optimum, especially when dealing with many UE at the same time. This research proposes the CRSMAS (Crew Rescheduling System with Multi Agent System) approach as an alternative that may help supervisors to make quick rescheduling decisions by automating the crew rescheduling process. A Multi Agent System (MAS) is considered suitable to support this rescheduling because agents can dynamically adapt their behaviour to changing environments and they can find solutions quickly via negotiations and cooperation between them. To evaluate the CRSMAS, two types of experiment are carried out: Single Event and Multiple Events. The Single Event experiment is used to find characteristics of crew schedules that influence the crew rescheduling process while the Multiple Events experiment is used to test the capability of CRSMAS in dealing with numerous events that occur randomly. A wide range of simulation results, based on real-world data, are reported and analysed. Based on the experiment it is concluded that CRSMAS is suitable for automating the crew rescheduling process and capable of quick rescheduling whether facing single events or multiple events at the same time, the success of rescheduling is not only dependant on the tool but also to other factors such as the characteristics of crew schedules and the period of the UE, and one limitation of CRSMAS that was discovered is it cannot simulate different type of events at the same time. This limitation is because in different events there are different rules but, in Virtual World, agents can only negotiate with one set of rules at a time.Financial support was obtained from the Universiti Teknikal Malaysia Melaka (UTeM)

A multi-agent system for a bus crew rescheduling system

Unpredictable events (UE) are major factors that cause disruption to everyday bus operation. In the occurrence of UE, the main resources - crews and vehicles - are affected, and this leads to crew schedule disruption. One way to deal with the problem is crew rescheduling. Most of the current approaches are based on static schedules do not support rescheduling in a real-time scenario. They have the ability to reschedule but a new complete schedule is produced without concerning the real time situation. The mathematical approaches which are used by most scheduling packages have the ability to search for optimum or near optimum schedules but they are usually slow to produce results in real-time because they are computationally intensive when faced with complex situations. In practice, crew or bus rescheduling is managed manually, based on the supervisor's capabilities and experience in managing UE. However, manual rescheduling is complex, prone to error and not optimum, especially when dealing with many UE at the same time. This research proposes the CRSMAS (Crew Rescheduling System with Multi Agent System) approach as an alternative that may help supervisors to make quick rescheduling decisions by automating the crew rescheduling process. A Multi Agent System (MAS) is considered suitable to support this rescheduling because agents can dynamically adapt their behaviour to changing environments and they can find solutions quickly via negotiations and cooperation between them. To evaluate the CRSMAS, two types of experiment are carried out: Single Event and Multiple Events. The Single Event experiment is used to find characteristics of crew schedules that influence the crew rescheduling process while the Multiple Events experiment is used to test the capability of CRSMAS in dealing with numerous events that occur randomly. A wide range of simulation results, based on real-world data, are reported and analysed. Based on the experiment it is concluded that CRSMAS is suitable for automating the crew rescheduling process and capable of quick rescheduling whether facing single events or multiple events at the same time, the success of rescheduling is not only dependant on the tool but also to other factors such as the characteristics of crew schedules and the period of the UE, and one limitation of CRSMAS that was discovered is it cannot simulate different type of events at the same time. This limitation is because in different events there are different rules but, in Virtual World, agents can only negotiate with one set of rules at a time.EThOS - Electronic Theses Online ServiceUniversiti Teknikal Malaysia Melaka (UTeM)GBUnited Kingdo