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Establishing uncertainty analysis procedures for inaccuracies in operational ship stability


Enshaei, H and Woodward, MD and Uge, C and Kianejad, S, Establishing uncertainty analysis procedures for inaccuracies in operational ship stability, Proceedings of the 1st International Conference on the Stability and Safety of Ships and Ocean Vehicles, 7-11 June 2021, Glasgow, pp. 1-11. (2021) [Refereed Conference Paper]

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The ship stability is essentially assessed for all ships before, after and during the operation. The purpose of assessing ship stability is to ensure the ability of ship to float and return to an upright position if inclined under the action of an external force. Ship stability, as with other critical parameters relating to ship operations, is of paramount importance and should therefore be dealt with accordingly with an appropriate uncertainty analysis. Uncertainty analysis is commonly utilised in a design to establish the uncertainty in result as a function of the input variable. This can in turn be utilised to establish an interval about the result that may be expected to encompass a large fraction of the distribution of values that could reasonably be attributed to the measurement. This paper provides a methodology for calculating a confidence interval for the centre of mass of a ship in operation and ultimately, in any load condition.

The uncertainty for a sample containership was carried out by considering the effect of weights on the centre of gravity of the ship. It appears that variation in height of cargo in containers can change the 𝐾𝐺 by as much as 0.164m. The uncertainty of weighing appliances could be up to 250kg for individual container, and sediment in ballast tanks could potentially reduce the centre of gravity of the tank by -0.5m.

Item Details

Item Type:Refereed Conference Paper
Keywords:ship stability, uncertainty analysis, ship operation, ship centre of gravity
Research Division:Engineering
Research Group:Maritime engineering
Research Field:Naval architecture
Objective Division:Transport
Objective Group:Water transport
Objective Field:International sea freight transport (excl. live animals, food products and liquefied gas)
UTAS Author:Enshaei, H (Dr Hossein Enshaei)
UTAS Author:Woodward, MD (Associate Professor Michael Woodward)
UTAS Author:Kianejad, S (Mr Seyedsadreddin Kianejadtejenaki)
ID Code:145450
Year Published:2021
Deposited By:Seafaring and Maritime Operations
Deposited On:2021-07-21
Last Modified:2021-09-24

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