Abstract

Cette thèse se compose de trois articles autonomes, dont chacun correspond à un chapitre. Le premier chapitre, écrit conjointement avec Estelle Malavolti, étudie la conception optimale du contrat de réduction des retards signé entre un ANSP et une compagnie aérienne monopoliste. Dans la conception du contrat, nous considérons principalement le problème d’antisélection. En outre, nous effectuons une analyse comparatif-statique pour étudier les effets de la norme de sécurité et de la fréquence de vol sur les contrats optimaux. A la fin, nous utilisons des exemples numériques pour étudier le cas où un ANSP maximisant son bien-être doit utiliser des fonds publics pour fournir le service. Le deuxième chapitre étudie le double rôle des retards de congestion et de la différenciation horizontale des produits dans le choix du réseau aérien. Je trouve que, premièrement, en raison de l’inclusion des retards de congestion, la compagnie aérienne peut choisir le réseau point à point lorsque la désutilité des services avec une escale, engendrée par le temps supplémentaire du voyage, est relativement faible. Deuxièmement, sans tenir compte des investissements fixes de la compagnie aérienne dans le développement d’un aéroport de hub, le réseau 2-hub dominera les trois autres structures de réseau aussi longtemps que cela sera possible, car il implique la différenciation horizontale des produits sur plus de marchés que les trois autres structures de réseau. Le troisième chapitre, écrit conjointement avec Wanjun Yao et Shigeyuki Hamori, trouve empiriquement que l’efficacité de l’allocation des terres plus élevée améliore la productivité des terres moyenne de 29,1% et la plus grande taille de la ferme opérationnelle moyenne réduit la productivité des terres moyenne de 9,2%, ce qui implique que la commercialisation des terres agricoles en Chine améliore finalement la productivité des terres moyenne de 19,9%.

Abstract

TRA 2018, 7th Transport Research Arena, Vienne, AUTRICHE, 16-/04/2018 - 19/04/2018; In the context of the Franco-German research project Re(h)strain, this work focuses on a global system analysis integrating both safety and security analysis of international and/or urban railway stations. The Re(h)strain project focuses on terrorist attacks on high speed train systems and investigates prevention and mitigation measures to reduce the overall vulnerability and strengthen the system resilience. One main criterion regarding public transport issues is the number of passengers. For example, the railway station of Paris 'Gare du Nord' deals with a bigger number of passengers than the biggest airport in the world (SNCF open Data 2014), the Atlanta airport, but in terms of passengers, it is only around the 23rd rank railway station in the world. Due to the enormous mass of people, this leads to the system approach of breaking out the station into several classes of zones, e.g. entrance, main hall, quays, trains, etc. All classes are analysed considering state-of-the-art parameters, like targets attractiveness, feasibility of attack, possible damage, possible mitigation and defences. Then, safety incidence of security defence is discussed in order to refine security requirement with regard to the considered zone. Finally, global requirements of security defence correlated to the corresponding class of zones are proposed. A case study based on the works in Re(h)strain is used as an illustration to demonstrate how the above-mentioned security and safety requirements may be implemented and handled at train stations. Therefore, the different security measures proposed for an unaffected flow of passengers are correlated to existing ones, such as video surveillance and security personal patrolling. The results of sensor set-ups realised within the project and tested in real environment show new ways of implementing innovative techniques to security applications. Depending on the technology, sensor portals at the entrances of train stations or sensor nodes distributed throughout the station increase the level of protection achievable for the detection of threats as part of preventive security concepts. The fusion of data gained by different sensor systems, including person-tracking by non-visual object recognition and trailing, enables a core function of a security assistance system. This assistance system makes security personnel aware of threats and the location of possible carriers of suspicious material as a prior condition to successful intervention measures. The high level of automation reduces human intervention to a minimum. In the conclusion it will be recommended to think of international railway stations as complex interconnected systems which are made for sharing traffic flows. It means that thinking about local solutions may produce safety problems to connected zones due to possible overcrowding. Document type: Conference object

Abstract

TRA 2018, 7th Transport Research Arena, Vienne, AUTRICHE, 16-/04/2018 - 19/04/2018; Especially in inter-country areas, Crisis Management (CM) faces several challenges. Thorough preparation and anticipation are crucial organizational tools to address those challenges and enable proper reaction to crises. CM requires the joint effort of various stakeholders from different countries: public authorities, private companies, Non-Governmental Organizations (NGOs), etc. need to collaborate under specific, locally different regulations. The present paper includes a brief introduction to the state of the art of CM of international railways with special regard to the topics partnerships, leadership & communication as well as training. As part of a research project, a survey with international crisis management experts was conducted. Based on the survey results, a handbook containing transnational recommendations regarding the involved stakeholders and their responsibilities is developed. Of course, existing CM concepts of relevant organizations are taken into consideration for the development. The handbook was discussed with end-users in the course of a project workshop. In addition, when the crisis management is required, the response is coordinated within the framework of the National Crisis Management System (NCMS). The cooperation between these NCMSs leads to the concept of System-of-Systems (SoS). Based on Supervision Control Theory (SCT), we propose a formal model built from decomposition of NCMSs using a multi-model approach. The resulted framework offers a global view of the SoS and resolves problems of system's dependence and of operating mode management. The proposed model is designed by using the High Level Petri Nets (HLPNs) formalism and is illustrated with a crisis of a railway system. The main result of this paper is the comprehensive knowledge of current crisis management strategies in the context of cross-border incidents. Weaknesses in the existing system are identified and two approaches that seek to enhance CM are introduced.

Abstract

Proceedings of 7th Transport Research Arena : TRA 2018, VIENNE, AUTRICHE, 16-/04/2018 - 16/09/2018; Local scour is a major risk threatening the stability and sustainability of bridges across rivers and in coastal areas. The main purpose of this paper is to propose a monitoring technique based on the dynamic response of rods embedded in the riverbed. First, extensive laboratory tests are conducted to investigate the effect of scour on the vibratory response of different rods in sand and in saturated clay soil. Secondly, a numerical finite element model is developed and validated with these laboratory tests. This model is then used to assess the effect of the added mass of water on the sensor. Finally, based on the numerical and experimental results, a simplified analytical cantilever model is proposed to correlate the dynamic response of the rods to the current scour depth. Document type: Conference object