A curve that cuts all meridians of a rotating surface at the same angle is called a loxodrome. If the shape of the Earth is approximated by a sphere, then the loxodrome is a logarithmic spiral that cuts all meridians at the same angle and asymptotically approaches the Earth's poles but never meets them. Since maritime surface navigation defines the course as the angle between the current meridian and the longitudinal direction of the ship, it may be concluded that the loxodrome is the curve of the constant course, which means that whenever navigating on an unchanging course we are navigating according to a loxodrome.

Ionospheric delay is the major source of satellite positioning system performance degradation. Designers of satellite positioning systems attempt to mitigate the impact of the ionospheric delay by deployment of correction models. For instance, the American GPS utilises a global standard (Klobuchar) model, based on the assumption that the daily distribution of GPS ionospheric delay values follows a biased cosine curve during day-time, while during the night-time the GPS ionospheric delay remains constant. Providing a compromise between computational complexity and accuracy, the Klobuchar model is capable of correcting up to 70% of actual ionospheric delay, mainly during quiet space weather conditions. Unfortunately, it provides a very poor performance during severe space weather, geomagnetic and ionospheric disturbances. In addition, a global approach in Klobuchar model development did not take into account particularities of the local ionospheric conditions that can significantly contribute to the general GPS ionospheric delay. Current research activities worldwide are concentrating on a better understanding of the observed GPS ionospheric delay dynamics and the relation to local ionosphere conditions.Here we present the results of a study addressing daily GPS ionospheric delay dynamics observed at a Croatian coastal area of the northern Adriatic (position ϕ=45°N, λ=15°E) in the periods of quiet space weather in 2007. Daily sets of actual GPS ionospheric delay values were assumed to be the time series of composite signals, consisting of DC, cosine and residual components, respectively. Separate models have been developed that describe components of actual GPS ionospheric delay in the northern Adriatic for summer and winter, respectively. A special emphasis was given to the statistical description of the residual component of the daily distribution of GPS ionospheric delay, obtained by removing DC (bias) and cosine components from the composite GPS ionospheric delay.Future work will be focused on further evaluation and validation of a quiet space weather GPS ionospheric delay model for the northern Adriatic, transition to a non-Klobuchar model, and on research in local GPS ionospheric delay dynamics during disturbed and severe space weather conditions.

The proposed paper discusses multimodal container transport due to savings in external costs. Relevant data have been analysed by reviewing previous research and published works for making a synthesis of one’s own conclusions. The research findings showed that there is no significant difference in the share of external costs of container transport and transport of other types of cargo in great European seaports as well as in energy consumption of multimodal rail-inland ship container transport and the same transport mode of bulk cargo. Intermodal terminals have also their own external costs. In spite of a double railway operational cost, it is important to include the railway in the intermodal terminal. The inland waterway transport has much higher external costs than sea transport. Multimodal container transport does not necessarily lower external costs. The savings are more common if the location and type of intermodal terminal are selected properly, and the sea transportation is involved in the multimodal transport chain.

Space weather disturbances cause considerable effects on Global Navigation Satellite Systems (GNSS) performance and operation, affecting society and the economy due to the growing reliance on GNSS, especially in densely populated mid-latitudes. Recent studies hypothesised potential utilisation of the Disturbance storm-time (Dst) index for indication of an approaching ionospheric storm and possible deterioration of the GNSS positioning performance. We challenged the hypothesis in the case of the Halloween 2003 event in an attempt to confirm the direct correlation between the Dst index dynamics and the Global Positioning System (GPS) positioning performance in the mid-latitude Mediterranean area. Our results provide no evidence of the direct Dst-GNSS performance correlation for the observed event.

Container transport by sea has almost doubled in the last decade. Accordingly, container ships' size has increased significantly, and the latest container ships carry up to 24000 Twenty-foot Equivalent Units (TEU). In the near future, the appearance of container ships with a capacity of 25000 TEUs can be expected on the market, because the design is already available. It is known that 10-12% of transported containers contain International Maritime Dangerous Goods (IMDG) cargo. The above stated reasons directly impact the frequency of container ship fires in cargo spaces. According to the Insurance Companies, fires occur on average every two months, and this is a growing problem of container transport by sea. In this paper, 23 fires in the cargo area, either in cargo holds or on deck, were analysed. The analysis results determined the most common causes of fires and have shown that the current fire protection systems on container ships are ineffective. It is unacceptable that firefighting systems' inefficiency results in the loss of human lives, abandonment of vessels, environmental pollution, and extensive property losses related to cargo and ship structure. Due to all the above, it is necessary to continuously work on new regulatory and technical solutions to improve the fire safety of cargo areas on container ships.