A Rational Approach to the Ecological Transition in the Cruise Market: Technologies and Design Compromises for the Fuel Switch

Supporting policies to achieve a green revolution and ecological transition is a global trend. Although the maritime transport of goods and people can rightly be counted among the least polluting sectors, much can be done to further reduce its environmental footprint. Moreover, to boost the ecological transition of vessels, a whole series of international regulations and national laws have been promulgated. Among these, the most impactful on both design and operational management of ships concern the containment of air-polluting emissions in terms of GHG, NOx, SOx and PM. To address this challenge, it might seem that many technologies already successfully used in other transport sectors could be applied. However, the peculiar characteristics of ships make this statement not entirely true. In fact, technological solutions recently adopted, for example, in the automotive sector must deal with the large size of vessels and the consequent large amount of energy necessary for their operation. In this paper, with reference to the case study of a medium/large-sized passenger cruise ship, the use of different fuels (LNG, ammonia, hydrogen) and technologies (internal combustion engines, fuel cells) for propulsion and energy generation on board will be compared. By imposing the design constraint of not modifying the payload and the speed of the ship, the criticalities linked to the use of one fuel rather than another will be highlighted. The current limits of application of some fuels will be made evident, with reference to the state of maturity of the relevant technologies. Furthermore, the operational consequences in terms of autonomy reduction will be presented. The obtained results underline the necessity for shipowners and shipbuilders to reflect on the compromises required by the challenges of the ecological transition, which will force them to choose between reducing payload or reducing performance

Listeria abdominal endograft infection miming pseudoaneurysm treated with in-situ aortic reconstruction: a case report

We report the case of a 72-year old man previously treated with an aortic endograft for an abdominal aortic aneurysm. After 3 years the patient developed a sepsis. Imaging and blood exams detected an endograft infection related to Listeria monocytogenes. Patients underwent endograft removal and in-situ aortic reconstruction with a cryopreserved allograft. A continuous antibacterial therapy has been established. One-month follow-up revealed the absence of clinically relevant infection with patency of the graft and absence of biochemical inflammatory markers

An Application of Modular Design in the Refitting of a Hybrid-electric Propelled Training Ship

Nowadays specific ships are used to train students as sailors. As historical vessels are conveniently employed to this aim, the average age of these ships is usually high. In order to amortize operating and maintenance costs, the training ships\u2019 ownership (except for naval ones) is shared among multiple entities and schools. Moreover, generally these vessels are used in coastal navigation. The consequent operational profile imposes the need to rearrange the ship internal spaces according to the shipowner who will use it. Considering all these reasons, a modular design approach can be adopted in the refitting process, while reverse engineering techniques and integrated design tools should be used for the reconstruction when the original technical documentation is not available. In this context, hybrid-electric propulsion systems can be proposed as effective to enable the Zero Emission Mode, thus reducing the vessel\u2019s environmental impact during the training. By doing this, three goals are achieved to extend the ship operational life: ease of rearrangement of the internal spaces for different uses, reduction of operating/maintenance costs and eco-sustainability in coastal navigation. In this paper, after a description about modular design and hybrid electric technologies, the refitting project of the M/N \u201cUmberto d\u2019Ancona\u201d is discussed. The latter is the training ship of \u201cTomaso di Savoia Duke of Genoa\u201d, the nautical institute in Trieste, Italy