When two ships are operating in proximity, the resulting hydrodynamic forces can cause significant loads on the ships. Such problems can be solved by a numerical approach, based on the use of a three-dimensional panel method. The objective of this paper is to compute the case of two ships which are allowed to move under the influence of the hydrodynamic forces. In this problem, the direct evalu...

Synthetic aperture radar (SAR) imagery from the sea can contain ships and their ambiguities. The ambiguities are visually identifiable due to their high intensities in the low radar backscatter background of sea environments and can be mistaken as ships, resulting in false alarms in ship detection. Analysing polarimetric characteristics of ships and ambiguities, we found that (a) backscattering...

This paper focuses on the feature analysis of moving ships in synthetic aperture radar (SAR) images and proposes a detection algorithm for ships. The algorithm first detects all the candidate ships and provides analysis of structural features with the discrete topology. In the analysis of structural features, aspect ratio and ship’s navigation direction can be used to construct feature confiden...

A common problem faced by carriers in liner shipping is the design of their service network. Given a set of demand to be transported and a set of ports, a carrier wants to design service routes for his ships as efficiently as possible, using the underlying facilities. Furthermore, the profitability of the service routes designed depends on the paths chosen to ship the cargo. We present an integ...

BACKGROUND With a heightened increase in concern for an influenza pandemic we sought to better understand the 1918 Influenza pandemic, the most devastating epidemic of the previous century. METHODOLOGY/PRINCIPAL FINDINGS We use data from several communities in Maryland, USA as well as two ships that experienced well-documented outbreaks of influenza in 1918. Using a likelihood-based method an...

Understanding a ship’s present position has been one of the most important tasks during a ship’s voyage, in both ancient and modern times. Particularly, a ship’s dead reckoning (DR) has been used for predicting traffic situations and collision avoidance actions. However, the current system that uses the traditional method of calculating DR employs the received position and speed data only. Ther...

Synthetic Aperture Radar (SAR) ship detection is an important maritime application. However, azimuth ambiguities caused by the finite sampling of the Doppler spectrum are often visible in SAR images and are always mistaken as ships by classic detection techniques, like the Constant False Alarm Rate (CFAR). It is known that radar targets and azimuth ambiguities have different characteristics in ...

The U.S. Liberty Ship Building Program in World War II set a record—a total of 2700 Liberty Ships were built in 6 years, in order to support the battle against Nazi-Germany. However, numerous vessels suffered sudden fracture, some of them being split in half. This paper demonstrates and investigation of the Liberty Ships failure and problems, which reveals that the failures are caused by a comb...

ships’ magnetic anomalies are one of their main problems encountering sea mines and for the cases of submarines are one of the prominent factors, which causes their fast detection. the main aim of this paper is to design a degaussing system in order to minimize magnetic anomalies of ships. to achieve this goal, first, magnetic signature of a simple ship is simulated. then by utilizing three gro...

In 2006, we used the U.S. Coast Guard's Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of the vessels and 82% of the t...