Abstract

In this paper we explore tramp ship routing and scheduling. Tramp ships operate much like taxies following the available demand. Tramp operators can determine some of their demand in advance by entering into long-term contracts and then try to maximise profits from optional voyages found in the spot market. Routing and scheduling a tramp fleet to best utilise fleet capacity according to current demand is therefore an ongoing and complicated problem. Here we add further complexity to the routing and scheduling problem by incorporating voyage separation requirements that enforce a minimum time spread between some voyages. The incorporation of these separation requirements helps balance the conflicting objectives of maximising profit for the tramp operator and minimising inventory costs for the charterer, since these"br/"costs increase if similar voyages are not performed with some separation in time. We have developed a new and exact branch-and-price procedure for this problem. We use a dynamic programming algorithm to generate columns and describe a time window branching scheme used to enforce the voyage separation requirements which we relax in the master problem. Computational results show that our algorithm in general finds optimal solutions very quickly and performs much faster compared to an earlier a priori path generation method. Finally, we compare our method to an earlier adaptive large neighbourhood search heuristic and find that on similar-sized instances our approach generally uses less time to find the optimal solution than the adaptive large neighbourhood search method uses to find a heuristic solution. Document type: Book

Abstract

There is really no debate about the superior comparative efficiency of ships with respect to fuel consumption when calculated per deadweight tonne along routes of similar length. However, the emission figures calculated per deadweight tonne is only relevant for bulk transports, and fuel consumption per cargo tonne is quite different for typical short sea shipping services based on container or RoRo technologies. Further, other emissions to air, like sulphur dioxide, nitrogen oxides and particles, are typically very high for shipping – especially when no abatement technologies are applied.

Abstract

International audience; The development of renewable marine energies has its origin in the United Nations' Framework Convention on Climate Change, adopted on 9 May 1992, and in the additional protocol, adopted in 1997 in Kyoto. Although, for many years, the French legal system did not consider the specificities of ocean renewable energies, the French government now seems to have become aware of the importance of establishing an adapted legal framework. The boom of marine renewable energies is the result of proactive policies from a French nation that seeks to meet its international and European commitments. The French policy makes use of legal instruments that ensure programming and planning. The economic activities in the field of marine renewable energies make up a market to which access is regulated. This requires administrative procedures which are as varied as they are complex. © ISTE Ltd 2015. All rights reserved.

Abstract

En matière de transport maritime, deux mondes se côtoient depuis l'apparition du conteneur à la fin des années 1950 : d'un côté celui lié à la circulation des boîtes, de l'autre celui des marchandises qui ne peuvent être empotées dans ces caisses de métal. Le premier correspond à un marché construit par l'offre de lignes régulières et la notion de service maritime, le second s'organise d'abord en fonction de la demande de marchandises selon une navigation de vagabondage. Si les logiques qui les animent sont bien différentes, les deux sont confrontés aux enjeux de la globalisation, en particulier ceux liés à la durabilité d'un modèle économique d'inspiration libérale.

Abstract

Maritime industry plays a key role for economy of the European Union. During recent years in-creasing attention is paid to the education and training of seafarers as the seafarers and their knowledge are essential to sustainable development of the maritime cluster, as indicated in the maritime strategy of European Union. However, for successful implementation of the strategy understanding of current trends in the pool of seafarers is prerequisite. Therefore the aim of this article is to analyze parameters and processes of Latvian seafarer’s pool, based on information from database of Maritime Administration of Latvia Seamen Registry. The structure of database and data collected there gives possibility to analyze the processes taking into ac-count the global changes in shipping and their impact to the structure of the pool. Such analysis in combination with the calculations of economical value of seafarer’s pool creates the framework on which the decisions about the implementation of maritime strategy in Latvia can be taken.

Abstract

International audience; Nowadays, oil tankers represent 25% of the targets of maritime piracy attacks. The main goal of this paper is to propose an approach to evaluate the vulnerability of the maritime supply chain to piracy risk. This approach, based on spatial reasoning and modelling tend to measure the impact of piracy on the network by the changes on maritime network realized by disruptions. To achieve it, we use multi-agent system, which can be defined by a set of agent within a shared environment. Agents are entity which has their own goal, capacity and resources which induce a specific behavior. By using the sum of these behaviors, the main objective of this paper is to measure disruptions by a conceptual approach to qualify and quantify the piracy risk.