‘Close-quarters situation’ is a term used in the International Regulations for Preventing Collisions at Sea. As the term is not precisely defined, this paper analyses the interpretations and definitions of the term by various authors or courts, based on judicial processes and judgments. In the end, the authors suggest their own definition of the term ‘close-quarters situation’. Knowing the minimum distance from another ship and the time to the closest point of approach at which collision may still be avoided by one's own manoeuvre is information that every ship's officer needs to know. In accordance with the proposed definition of the term ‘close-quarters situation’, minimum distances between ships and time to the closest point of approach in which the ship can still take action to avoid a collision by its own manoeuvring are determined by means of simulations on a navigational simulator. A total of 168 simulations were performed with three fine-form vessel sizes and three full-form vessel sizes. Due to the extensive amount of data, the paper presents the results for one vessel only.

Typical application of bidirectional DC/DC power converter exists in hybrid cars. Recently, a similar approach has been applied in hybrid propelled ships as well. In this paper, a novel low power bidirectional DC/DC power converter of standard Buck/Boost topology has ben designed in order to explore possibilities of the high power design in maritime applications. In order to discover critical points of a design, thermal imaging has been investigated. The results clearly indicate that the proposed solution is more cost effective than a typical standard bidirectional DC/DC power converter. Likewise, the improvement in maneuvering of the propelled vessel system with two and more electric drives has been investigated and compared to a classical diesel, single engine propulsion system.