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<p>This dissertation studies coordination mechanism design for sustainable supply networks in a globalized environment, with the goal of achieving long-term profitability, environmental friendliness and social responsibility. We examine three different types of supply networks in detail.</p><p>The first network consists of one supplier and multiple retailers. The main issue is how to efficiently share a scarce resource, such as capacities for green technology, among all members with private information under dynamically changing environment. We design a shared surplus supply agreement among the members which can lead to both efficient private investments and efficient capacity allocation under unpredictable and unverifiable market conditions.</p><p>The second network is a serial supply chain. The source node provides critical raw material (like coffee cherries) for the entire chain and is typically located in an underdeveloped economy, the end node is a retailer serving consumer at a developed economy (like Starbucks Co.). We construct a dynamic supply agreement that takes into account the changing market and production conditions to ensure fair compensations so that the partners have the right incentives to work together to develop sustainable quality supply.</p><p>The third network is a stylized global production network of a multinational company consisting of a home plant and a foreign branch. The branch serves the foreign market but receives a key component from the home plant. The distinctive feature is that both facilities belong to the same company, governed by the headquarters, yet they each also have their own autonomies. We analyze the role of the headquarters in designing coordination mechanism to improve efficiency. We show the headquarters can delegate the coordination effort to the home plant, as long as it keeps veto power.</p> / Dissertation

During the past decade, Grid computing has gained popularity as a means to build powerful computing infrastructures by aggregating distributed computing capacity. Grid technology allows computing resources that belong to different organizations to be integrated into a single unified system image – a Grid. As such, Grid technology constitutes a key enabler of large-scale, crossorganizational sharing of computing resources. An important objective for the Virtual Organizations (VOs) that result from such sharing is to tame the distributed capacity of the Grid in order to manage it and make fair and efficient use of the pooled computing resources. Most Grids to date have, however, been completely unregulated, essentially serving as a “source of free CPU cycles” for authorized Grid users. Whenever unrestricted access is admitted to a shared resource there is a risk of overexploitation and degradation of the common resource, a phenomenon often referred to as “the tragedy of the commons”. This thesis addresses this problem by presenting two complementary Grid capacity allocation systems that allow the aggregate computing capacity of a Grid to be divided between users in order to protect the Grid from overuse while delivering fair service that satisfies the individual computational needs of different user groups. These two Grid capacity allocation mechanisms constitute the core contribution of this thesis. The first mechanism, the SweGrid Accounting System (SGAS), addresses the need for coordinated soft, real-time quota enforcement across Grid sites. The SGAS project was an early adopter of the serviceoriented principles that are now common practice in the Grid community, and the system has been tested in the Swegrid production environment. Furthermore, SGAS has been included in the Globus Toolkit, the de-facto standard Grid middleware toolkit. SGAS employs a credit-based allocation model where research projects are granted quota allowances that can be spent across the Grid resources, which charge users for their resource consumption. This enforcement of usage limits thus produces real-time overuse protection. The second approach, employed by the Fair Share Grid (FSGrid) system, uses a share-based allocation model where project entitlements are expressed in terms of hierarchical share policies that logically divide the Grid capacity between user groups. By coordinating local job scheduling to maintain these global capacity shares, the Grid resources collectively strive to schedule users for a “share of the Grid”. We refer to this cooperative scheduling model as decentralized Grid-wide fairshare scheduling.

Planifier les horaires des trains qui circulent sur un réseau constitue une tâche complexe. En Europe, elle s'inscrit dans un processus qui voit le gestionnaire d'infrastructure opérer des choix pour répartir une ressource rare, la capacité d'infrastructure, entre des usages concurrents - commerciaux (trains de voyageurs et de marchandises) et de maintenance (travaux) - et des demandeurs multiples. Dans ce travail, nous cherchons à mieux cerner comment s'organise et fonctionne le processus pour le réseau ferré français par le prisme du fret, activité ouverte à la concurrence depuis 2006 mais qui traverse une crise structurelle depuis plusieurs décennies. Les différentes facettes temporelles du processus de répartition des capacités constituent le fil conducteur de notre analyse. A travers une démarche croisant le point de vue du gestionnaire d'infrastructure et celui de ses clients, au premier rang desquels les entreprises ferroviaires, nous montrons que le fret occupe une place singulière dans ce processus qui se structure selon un calendrier spécifique, fruit de dispositions règlementaires européennes et d'héritages et de choix nationaux. La question de la qualité de sillons offerts par le gestionnaire d'infrastructure est appréhendée sous l'angle d'une articulation entre composantes de court et de long termes par rapport à l'échéance de circulation. Activité plurielle, le fret a besoin de flexibilité et de visibilité. Nous nous intéressons enfin aux sillons-catalogue en tant que dispositif participant à garantir de la capacité au fret. Une analyse de la méthode allemande, à travers le projet neXt, est proposée en guise de contrepoint. Nous mettons en évidence que l'équilibre entre des exigences industrielles (standardisation) et commerciales (personnalisation) dans la production des sillons est indispensable mais demeure délicat à établir / Train timetabling on a rail network is a complex task. In Europe, this issue lies within a process for which the infrastructure manager has to consider competing uses - passenger and freight trains as well as maintenance work - and several users of a scarce resource, infrastructure capacity. The aim of this research is to better understand the way this process is organised and works on the French rail network. We have chosen to tackle this issue focusing on freight as an activity which has been opened up to competition since 2006 but has experienced structural difficulties for decades. The various time aspects of the capacity allocation process are the key focus of our analysis. Our approach considers the perspectives of the infrastructure manager and of their customers, foremost among which are train operating companies. We highlight that freight occupies a unique place in this process which is based on a schedule resulting from both European regulations and the legacy of decisions taken at the national level. The issue of the quality of the train paths offered by the infrastructure manager is studied with a focus on the links between short and long term requirements with regard to the train running deadline. In spite of their diversity, we demonstrate that freight operators need flexibility and visibility. Finally, we analyse catalogue paths as a specific offer that aims to guarantee capacity for freight. The German method, through the neXt project, provides an alternative insight into this issue. Accommodating freight train paths into the timetable is essentially a necessary but delicate balance of interests: standardisation vs. customisation

Key performance measures for PC performance are timeliness and continuity. Whereas the first refers to the ability to obtain an appointment as soon as possible, the latter warrants a patient being able to see a familiar physician. In this context one has to consider the two types of appointments - same-day and prescheduled. The former is characterized by an urgent need of the patient to see a physician, the latter embodies non-urgent follow-up visits or regular appointments due to a chronic comorbidity. How should requests for appointments be assigned in order to deliver on the conflicting key metrics? What impact does the presence and the location of prescheduled appointments have in this context? How does the capacity allocation between prescheduled and same-day demand influence the decision making in the clinic? Using a stochastic dynamic program to model the dynamics of practice, we explore various ways of managing the inherent flexibility of physicians to see each others’ patients. Patients are calling in for same-day appointments. Thus, assignment decisions have to be made dynamically in real time under uncertainty of future demand and in presence of prescheduled appointment slots. The study consists of three parts: first, we examine the impact of the location of prescheduled appointments on the performance of the clinic. Second, we use our structural insights gained in the first part in order to derive implementable heuristic assignment policies. Third, we evaluate the performance of the heuristics in comparison to the optimal solution gained in the stochastic dynamic program and derive implications for the practice of primary care.

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Le transport fluvial de conteneurs constitue une activité économique importante qui suscite un intérêt grandissant de la part de scientifiques. Considéré comme durable et économique, le transport par barge a été identifié comme étant une alternative compétitive pour le transport de marchandises, en complément des modes traditionnels de transport, routier et ferroviaire. Néanmoins, les travaux de recherche en rapport avec la planification et le management du transport par barge, en particulier dans le contexte du transport intermodal, sont encore peu abondants. Le but de cette thèse est d’apporter une contribution dans ce domaine, par la proposition de modèles et de méthodes de planification et gestion avancées, dans le cadre d’un système d’aide à la décision pour le transport de conteneurs par barge développé pour accompagner les opérateurs de transport. La méthodologie proposée fait appel à des concepts et principes de gestion du revenu, des ressources et des services de transport pour la conception de plans de services réguliers avec horaires, au niveau tactique. Les opérateurs de transport peuvent ainsi offrir des plans de transport avec des services plus flexibles pour leurs clients, tout en assurant un meilleur niveau de fiabilité. Plus de demandes de transport pourront ainsi être satisfaites, avec globalement une plus grande satisfaction des chargeurs. Une originalité importante proposée par notre approche est l’utilisation de principes et techniques de gestion du revenu (segmentation du marché, classes tarifaires...) aussi bien au niveau opérationnel de la modélisation qu’au niveau tactique. Les problèmes d’optimisation sont formalisés sous forme de modèles de programmation linéaire mixte en nombres entiers (PLNE), implémentés et testés sous différentes configurations de réseaux de transport et différents scénarios de demandes, et ce pour chaque niveau de décision. Au niveau tactique, une nouvelle approche de résolution, combinant la recherche adaptative à voisinage large (ALNS) et la recherche taboue, est proposée pour résoudre des problèmes PLNE de grande taille. Une plateforme de simulation, qui intègre les niveaux tactique et opérationnel de prise de décision, est proposée pour la validation du système d’aide à la décision sous différentes configurations : différentes topologies du réseau physique, différents paramètres pour la gestion du revenu, différents degrés de précision caractérisant les prévisions de demande. Pour l’analyse des résultats numériques ainsi obtenus, plusieurs types d’indicateurs de performance sont proposés et utilisés. / Barge transportation is an important research topic that started to draw increasing scientific attention in the recent decade. Considered as sustainable, environment-friendly and economical, barge transportation has been identified as a competitive alternative for freight transportation, complementing the traditional road and rail modes. However, contributions related to barge transportation, especially in the context of intermodal transportation, are still scarce. The objective of this thesis is to contribute to fill this gap by proposing a reactive decision support system for freight intermodal barge transportation from the perspective of the carriers. The proposed system incorporates resource and revenue management concepts and principles to build the optimal set of scheduled services plans at the tactical level. Carriers may thus benefit from transportation plans offering increased flexibility and reliability. They could thus serve more demands and better satisfy customers. One novelty of the approach is the application of revenue management considerations (e.g., market segmentation and price differentiation) at both operational and tactical planning levels. The optimization problems are mathematically formalized and mixed integer linear programming (MILP) models are proposed, implemented and tested against various network settings and demand scenarios, for each decision level. At the tactical level, a new solution approach, combining adaptive large neighborhood search (ALNS) and Tabu search is designed to solve large scale MILP problems. An integrated simulation framework, including the tactical and the operational levels jointly, is proposed to validate the decision support system in different settings, in terms of physical network topology, revenue management parameters and accuracy degree of demand forecasts. To analyze the numerical results corresponding to the solutions of the optimization problems, several categories of performance indicators are proposed and used.