a b s t r a c tHydrodynamic models and coefficients are important parameters for predicting the maneuverability of a remotely operated vehicle (ROV). In this study, we present an experimental analysis of the hydrodynamic behavior of a new ROV with an asymmetric shape, which has a high capacity for holding more instruments onboard than other ROVs. We performed a series of towing tests where this ROV moved in a vertical plane. We provide the fitting formulae for forces and moments, as well as the corresponding hydrodynamic coefficients, which can be used to simulate the motions and to predict the maneuverability of the ROV. We also discuss the effects of the ROV's asymmetric shape on its hydrodynamic coefficients.

To eliminate the introduction of invasive marine species and the disadvantages of ballast water (BW) treatment systems a new concept in ship design was developed to be alternative of ballast water system. Non-Ballast ships were rarely mentioned in China even they were studied widely worldwide. In this paper, the different types of non-ballast water ship were reviewed, to be classified in order to facilitate the study of such types of vessels and serve as a base for the development.

This paper will present an experimental study on inertial hydrodynamic behaviors of an openframe ROV (Remotely Operated Vehicle) that has a complex open-frame hull but has a large capacity holding more instruments on board than other ROVs. A 1:4 scaled model has been tested by a VPMM (vertical planar motion mechanism) in the circulating water channel of Harbin Engineering University. The inertial coefficients, which can be used for simulating the motions and so for predicting the maneuverability of the ROV, will be presented. Particular attention will be paid to discuss the properties of the cross inertial coefficients (these related to the inertial forces/moments induced by the motion in other directions).

The importance of the human element in maritime safety is increasingly being recognized by the shipping and offshore communities. In this paper, the author is going to make an introduction of the application of the human factors in maritime technology in recent years, and talk about the failures of situation awareness which are exceedingly common and need to be handled.

Due to incredibly advancing technology and reduced manning levels in the maritime industry there is now a cultural shift in the maritime industry toward increased levels of automation in tasks, particularly with regard to navigation systems. But there are two sides to the automation advances. Increasing automation causes the loss of situation awareness, which can significantly affect performance in abnormal, time-critical circumstances. This paper presents an overview of the application of automation in marine system and its impact to the systems performance.