Optimization of routing considering uncertainties (original) (raw)

Risk-based onboard guidance to the master for avoiding dangerous seaways

The concept of a ship specific Decision Support System (DSS) for onboard navigational guidance to mitigate the risk related to the seakeeping performance of ships is introduced. The developed approach utilizes data related to the prevailing operational, loading and environmental conditions, which can be random and uncertain, as well as to the theoretical hydrodynamic responses of the ship in order to evaluate the related risk and explore for possible lower risk options. The involved probabilistic analysis is conducted by use of numerical simulation/sampling methods, like Monte Carlo simulation as well as FORM/SORM probabilistic assessment methods known from their application so far to ship's structural reliability analysis. The proposed risk-based DSS concept proved feasible for onboard/online navigational guidance to the master, disposing practical computational efficiency for the demanding onboard risk evaluation problem.

On Board Assessment of Seakeeping for Risk-based Decision Support to the Master

A probabilistic assessment method for the seakeeping of ships suitable for implementation in riskbased Decision Support Systems (DSS) aiming at the onboard navigational guidance to mitigate risks related to the ship's seakeeping performance, has been investigated and is presented in this paper. The related probabilistic analysis is conducted by use of numerical simulation/sampling methods, like Monte Carlo simulation as well as FORM/SORM probabilistic methods known from their application so far to ship's structural reliability analysis. The method proves practical computational efficiency for the demanding onboard risk evaluation.

Development of Solution for Safe Ship Considering Seakeeping PERformance20200514 21389 1dzonuz

the International Journal on Marine Navigation and Safety of Sea Transportation, 2018

In recent years, safety of a ships has become one important issues needed to solved as soon as possible in ship navigation. Optimal weather routing is one of best solution for ensuring safe operation of a ship with a with short passage time or minimum energy to avoid a certain excessive motion. This paper introduced the development of solution for safety and optimal weather routing a ship considering seakeeping performance based on model test result. This study introduced how to apply A* algorithm based on result of the seakeeping model test for determining the optimal ship routes. Seakeeping model test of 8600 TEU container ship was carried out in Changwon National Universityʹs seakeeping basin and its RAOs at various frequencies were used to predict the RMS motion values in irregular waves. The specially modelled path‐cost function and the safety constraints were proposed for finding the optimal path of the ship. The comparison of ship performances estimated by great circle’s path and estimated optimal route during the voyage of the ship was investigated.

A decision support system for mission-based ship routing considering multiple performance criteria

Reliability Engineering & System Safety, 2016

It is crucial to evaluate the structural risk associated with marine vessels subjected to inclement weather and sea conditions when developing a decision support system for ship routing. The generalized decision making framework developed in this paper performs a variety of tasks, including, but not limited to quantifying the flexural and fatigue performance of ship structures and employing multi-attribute utility theory to evaluate ship mission performance. A structural reliability approach is utilized to compute the probability of failure considering the uncertainty in structural capacity and load effects; specifically, effects of flexural and fatigue damage are investigated. The expected repair cost, cumulative fatigue damage, total travel time, and carbon dioxide emissions associated with ship routing are considered as consequences within the risk assessment procedure adopted in this paper. Additionally, the decision maker's risk attitude is integrated into the presented approach by employing utility theory. The presented methodology can assist decision makers in making informed decisions concerning ship routing. In order to illustrate its capabilities the approach is applied to the Joint High-speed Sealift Ship (JHSS).

Optimizing maritime travel time reliability

Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, 2012

Travel time reliability optimization problems generally cannot be formulated in direct mathematical form due to complexity of precise information. Classically, qualitative form of objective function and/or constraints does not allow the decision maker to represent it in a typical form of standard optimization model. This article attempts to resolve travel time reliability optimization problem of maritime transportation. The marine vessel’s travel time consists of seven time components. The travel time reliability is considered in a possibilistic manner, and then the reliability optimization problem with budgetary constraints and stage-time limitations is formulated. Next, algorithmic framework for solution of the possibilistic programming has been proposed, followed by a suitable illustration. Finally, this article investigates the parameter sensitivity that has consequences in the marine vessel’s transportation decision making. The proposed programming model is useful in the decisi...

A Prototype of Ship Routing Decision Support System for an Operational Oceanographic Service

TransNav, the International Journal on Marine Navigation and Safety of Sea Transportation, 2013

A prototype for an operational ship routing Decision Support System using time-dependent meteo-oceanographic fields is presented. The control variable is ship course, which is modified using a directional resolution of less than 27 degrees. The shortest path is recovered using a modified Dijkstra's algorithm. Safety restrictions for avoiding surfriding and parametric rolling according to the guidelines of the International Maritime Organization (IMO) are implemented. Numerical experiments tailored on a mediumsize vessel are presented and perspectives of development of the system are outlined.

Reliability informed routing for Autonomous Sailing Craft

EasyChair Preprints, 2018

This paper introduces a novel method for modelling the influence of likely autonomous sailing craft failure conditions into the route planning algorithm. The accuracy of the original route planning algorithm is quantified using numerical error estimation techniques. It was found that over the course of a TransAtlantic voyage a grid size of 36 km produced an error of ±2.1 hours over the course of a 703.25 hr voyage. The implementation of the failure model within the routing algorithm is verified using a control weather scenario. This verification is shown to be significant with respect to the method's numerical error. Future work will involve gathering evidence on failure criteria in order to update the failure model.