جستجوی مقالات مرتبط با کلیدواژه « kwon method » در نشریات گروه « عمران »

Nowadays, considering the importance of marine commerce, monitoring the marine navigation and routing the ships could be regarded as important issues. Moreover, specifying the weather condition of the marine environment for minimizing the damages and fatalities to vessels, crews and cargos is vital. Hence, weather routing is absolutely crucial. In addition, due to the high cost of voyage, the duration of voyage is one of the essential parameters of weather routing.
The aim of this research is to minimize the voyage duration regarding the weather conditions. The marine environment is simulated by a grid of weather data which has the resolution of 0.25 D that is updated every 6 hours. The data is downloaded from European Centre for Medium Range Weather Forecasts (ECMWF). Following that, the weight of each edge is calculated with respect to the time in which the vessel passes the edge. Travel time is related to the impact of wave, wind and sea depth on vessel’s speed which is computed based on Kwon method and Lackenby’s formula. Finally Dijkestra algorithm is applied for calculating the optimum route.
The studied area located in the north of Indian ocean in Persian gulf, Oman Sea and Arabian Sea. The model is implemented in two different weather conditions (calm and rough conditions) for calculating minimum time route between Pipavav port ( ) in India and Bushehr port ( ). The results indicate that although the voyage distance increased in this model, the duration of voyage decreased. Thus, the cost of voyage dropped noticeably. In addition, the depth of the marine environment determines the route of journey in the calm weather conditions because of lack of existence of high seas and storm in front of the ship. In the rough weather conditions the weather condition parameter (speed and direction of the wind and height and direction of the wave) has more effect than depth parameter in order to prevent the ship from navigation in high seas in which the ship's speed reduces dramatically. Moreover, results show that in the bounded seas like Persian Gulf with small area with respect to spatial resolution of marine environment (the resolution of the weather data) in which the weather condition between neighbouring cells does not change obviously, depth parameter is the critical parameter to determine the journeys path.