Wyniki wyszukiwania - BazTech

Ograniczanie wyników

3 TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

Powiadomienia systemowe

Sesja wygasła!

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Onboard Wave Sensing with Velocity Information GPS

Aray Y., Pedersen E., Kouguchi N., Yamada K.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

2011

Vol. 5, no. 2

205--211

Even though it is essential that the wave information promotes greater safety also efficiency to navigate and/or operate a ship not only ocean going but also docking/landing, it is very difficult to sense a wave information such as wave heights and periods or wave lengths in real time at the present time. On the other hand, the Velocity Information (VI) GPS is developed as the stand-alone 3D velocities measurement equipment of which accuracies are precise (less than 1 cm/s) and the coverage is all over the world. It is able to drive the wave information from the time history of not only wave amplitudes but also wave velocities. The algorithm to sense the wave information such as not only significant wave height but also plural wave heights and period intervals of encounter was presented by the authors in IAIN2009 and ANC2010. In this paper, the introduction and the performance of wave sensing with VI-GPS and some results of onboard experiments are described and discussed.

Application of 3-D Velocity Measurement of Vessel by VI-GPS for STS Lightering

Yoo Y., Pedersen E., Tatsumi K., Kouguchi N., Arai Y.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

2009

Vol. 3, no. 1

43--48

A lightering operation is a type of Ship-To-Ship (STS) operation where two ships are together in open waters and transfer the cargo e.g. crude oil, LNG. High skills and experience are required by the human operators as no relevant equipment for determining the relative speeds and distances with sufficient accuracies has been implemented. The officer in charge of an STS lightering takes the decision on adequate maneuvering orders based on predominantly visual observations during the final approach. Landing on all fenders simultaneously is an objective in order to minimize ship-fender contact forces, but this is rather difficult to achieve in practice even in calm sea due to the effect of hydrodynamic interaction when the ships are closing in. Furthermore, currents that are present in the lightering zone add to the operational complexity. A field measurement experiment has been carried out with a Velocity Information GPS (VI-GPS) system installed onboard a ferry approaching port for berthing which is similar to an STS lightering. The paper proposes to apply VI-GPS as input sensor to a decision-support and guidance system aiming to provide accurate velocity information to the officer in charge of an STS operation. It is argued that DOP of VI-GPS is related to the velocity error.

On an Advanced Shipboard Information and Decision-making System for Safe and Efficient Passage Planning

Hansen S. V., Pedersen E.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

2008

Vol. 2, no. 1

69--73

Shipboard weather information and decision-support systems have been developed to assist the officer on watch by supplying dedicated weather forecasts along a planned route. An added value can be achieved by combining an existing system with functionalities providing information about the ship’s performance in a seaway and an optimum routing algorithm. This paper describes functionalities for predicting slamming, green water on deck, synchronous and parametric roll and the implementation in an existing system to support safe and efficient ocean passage planning. A full scale test on board a container ship crossing the North Atlantic Ocean has been carried out in order to gain operational experience for evaluation of the concept. Further testing is required for validation purposes.