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Ro-Ro shipping is a dominant form of short sea freight transport. Ro-Ro ship operators are today unable to provide customers with precise information about when trailers are available for pickup by customers on the terminal despite vessel arrival times being well known in due time. This results in reduced truck utilization, longer waiting time for drivers, less efficient yard space utilization, potential terminal congestion and dissatisfied customers. In this paper the cargo unit discharge time estimation problem of Ro-Ro shipping is solved in collaboration with a European short-sea Ro-Ro shipping company. A module-based framework using statistical analysis for estimating the discharge time is proposed and tested. The initial framework is able to estimate the earliest pickup time of each individual truck or trailer within 1 hour accuracy for up to 70% of all cargo. The results of the study show potential for improving performance and accuracy. Further investigation and testing is currently ongoing by the case company based on the results from this study.

Stowage planning is at the essence of a maritime supply chain, especially for short sea Ro-Ro ships. This paper studies stowage optimisation of Ro-Ro ships with a focus on stability constraints and the applicability of models. The paper contributes to short sea Ro-Ro ship stowage in two ways. First, we propose an integrated approach of designing stowage models with the consideration of loading computers. Second, we present a mathematical formulation of the Ro-Ro Ship Stowage Problem with Ballast Water with a discretisation method, to generate an optimal stowage plan which meets stability requirements by means of the weight of cargoes instead of excess ballast water, i.e. excess fuel consumption. Computational tests based on empirical data indicate significant savings and potential of model application in the real world. Preliminary results show 57.69% ballast water reduction, equivalent to 6.7% fuel savings and CO2 reduction. Additional tests on instances with various cargo weight distribution and discretisation levels are conducted, and finally, improvements are suggested for further research considerations.

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Maritime transport is the backbone of global trade. In Europe, short sea Roll-on/Roll-off (RoRo) shipping is a dominant transportation mode due to its flexibility and connectivity. Faced with many challenges to comply with international regulations and remain competitive, there calls for a need for researchers to investigate inefficiencies and propose solutions, as scarce research is found related to the RoRo shipping industry. Thus, the PhD study aims to contribute to the field of sustainable RoRo cargo operations with a focus on stowage through digitalization and optimization methods. The principle is to develop solutions that can be implemented and integrated into planning tools to support decision makings of practitioners.Specifically, this thesis investigates the problems of stowage planning, dual cycling, and cargo discharge time estimation, inspired and motivated by DFDS, one of the largest short sea RoRo shipping companies in Europe. Thanks to our close collaboration, primary inefficiencies are identified and problems are formulated in the industry setting. Mathematical models, a heuristic, and a statistical framework have been proposed and tested on real data. Results indicate that this thesis has a significant impact on improving sustainability, in particular, fuel and emission reduction of RoRo shipping industry.The thesis has demonstrated how optimization and statistical methods can contribute to solving complex industrial problems. This is believed to be of great interest to both the maritime community and the data science community. The work resulted in four research articles: three published and one under review. Finally, the thesis closes with a conclusion and future work relevant to both communities in order to build a more sustainable the RoRo shipping industry.iii ResuméMaritim transport er rygraden i den globale handel. I Europa er short-searoll-on/roll-off (RoRo) shipping en dominerende transportform på grund af dens fleksibilitet og sammenkobling med andre transportformer. Branchen står over for mange udfordringer for at overholde internationale regler og forblive konkurrencedygtige, og derfor er der et behov for forskning der undersøger ineffektivitet og foreslår løsninger, der bidrager til RoRo-industrien, da området mangler yderligere forskning. Ph.d.-afhandlingen har således til formål at bidrage til baeredygtig RoRo-drift med fokus på stowage gennem digitaliserings-og optimeringsmetoder. Princippet er at udvikle løsninger, der kan implementeres og integreres i planlaegningsvaerktøjer til at støtte beslutningstagere i industrien.Specifikt undersøger denne afhandling problemerne med stowage planning, dual cycling og estimering af cargo discharge time inspireret og motiveret af DFDS, et af de største short-sea-RoRo-rederier i Europa. Takket vaere vores taette samarbejde identificeres primaere ineffektiviteter, og problemer formuleres så taet på virkeligeheden som muligt. Matematiske modeller, en heuristik og en statistisk ramme er blevet foreslået og testet på reelle data. Resultaterne ind...