Zvonimir Lušić

Models for Estimating the Potential Number of Ship Collisions

This paper analyses two different methods of estimating ship collision candidates. The first one is an analytical approach ; accordingly, an overview of various analytical expressions for estimating the number of collision candidates for three main situations (encounter, overtaking, and crossing) will be presented. The second is a simulation approach: the paper will present how to simulate ship movements by replacing them with circles in order to obtain a graphical presentation of ship movements in the zone of danger, including the calculation of collision candidates. The applied simulation model will also feature three main situations, i.e. encounter, overtaking, and crossing, and the results of simulations will be compared with the results of analytical models. The results and conclusions should improve the existing models for obtaining the potential number of ship collisions and encourage new advanced simulation methods.

Ranking of sailing routes according to the potential number of groundings

AbstractThe paper presents the selection of ship sailing routes in the coastal area according to the probability of grounding. Taking into consideration the dangers in the heading direction as well as the vicinity and length of the coastline parallel to the ship course, the paper will try to propose a model for choosing the sailing route with the smallest possibility of grounding. The estimation of the dangers on the routes will be based on the potential number of groundings; human factor will not be taken into account, assuming that a human error on each route will have the same probability of occurrence.

Astronomical position without observed altitude of the celestial body

The basis of all recommended methods for obtaining position by using celestial bodies is the known altitude of the celestial body being observed. Accordingly, it is necessary to have a sextant, classic or with an artificial horizon, or some other device that can measure altitude. However, there is a way to obtain position using astronomical navigation without determining the altitude of a celestial body, and this method will be analysed in this paper. The introduced method requires only precise measurement of the azimuth, and is based on determining two positions close to the dead reckoning position and lying on the isoazimuthal curve, i.e. a curve of the same great circle azimuths of a celestial body. Furthermore, the model assumes that a part of this curve, between the selected positions, can be replaced by a straight line. Special attention will be given to the analysis of errors of the line of position for various azimuth errors and various dead reckoning (assumed) positions. It will also be shown how a modern Electronic Chart Display and Information System (ECDIS) can help in approximate position determination, knowing only the azimuths of celestial bodies.

Analysis of development, potential and importance of the Northern Sea route

Today, almost 80% of cargo is transported by sea. Most of the global maritime shipping operations are performed in the direction East – West, through the southern routes, i.e. Singapore - Suez Canal - Gibraltar - Europe. The total fuel cost is the major concern and the main drawback of these routes. According to the latest statistics and analyses, the price of fuel is growing and such a trend will cause a great impact on the economies of developing countries. For these reasons, new alternative maritime routes, in which the optimization of transportation in the maritime transport network can be achieved, are to be found. There is a possibility of establishing such routes in the areas of high latitudes where climatological changes and diminishing ice open up entirely new possibilities for shipping and present completely new challenges in the global shipping industry. Through the comparative analysis of the main routes and the SWOT method, this paper discusses the advantages, potential and importance, as well as the level of reliability, threats and disadvantages of using the areas of high latitude in maritime transport.