High-precision localization of pipeline damage using acoustic emission technology in the marine environment remains challenging. A hybrid path optimization-based localization method for structural damage source localization is proposed. First, the short-time Fourier transform (STFT) maps acoustic signals into the time-frequency domain, with K-means cluster grouping signals to separate different damage sources. Subsequently, the ROTH dual-weighted cross-correlation algorithm is employed to accurately estimate the time difference of acoustic wave arrivals at sensors under strong noise conditions, extracting temporal characteristics of the acoustic waves. Next, an initial propagation path is generated via the Rapidly-exploring Random Tree (RRT) algorithm, and further optimized through an improved D* dynamic path optimization algorithm to determine the optimal propagation path. Finally, acoustic emission source locations are calculated by using hyperbolic equations and weighted least squares based on geometric localization methods. Experimental results demonstrate that this method can accurately locate the structural damage source in complex environments, significantly outperforming traditional approaches.

Polar navigation is the guarantee for ships to achieve scientific research and safe navigation in the polar area. At present, there are many studies on the theory of polar navigation in China about the arrangement of Inertial Navigation System (INS), the availability of satellite navigation polar area, multi-sensor integrated navigation, etc. But there are still blanks in the application of polar navigation and ice exploration equipment in the high latitude navigation engineering in the polar area. In order to solve the engineering application problems of the device in the polar region from the system level, the paper combines the theory to analyze the polar environment and ship based in the polar region on the performance of the navigation device, and combines the research status of the ice exploration radar, inertial navigation, satellite navigation, electronic charts, satellite communication and other devices in the polar region, studies the working process of the design of the ice navigation device, and discusses the direction of future research and development of the navigation device in China.

A large number of crew will work and live on board for many large special purpose vessels with the continuous exploration of ocean, which will put forward higher and higher requirements for the ship safety. In general, safe return to port is for passenger ships, and there are few engineering ships can meet this requirement. This paper introduces the design method of the electrical system and its influence on the design of the electrical system for a deepwater pipe-laying crane vessel that meets the requirement of safe return to port. It can provide reference for the design of the similar ships in the future.