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Investigation of a Magnetic-Type Waterproof Oil Spill Stop Device for Ships. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2020. [DOI: 10.3390/jmse8090636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
If a ship’s hull or tank breaks, the ship may sink, or oil spills can cause enormous damage to the environment. If the ship is equipped with a capable, cost-effective oil or liquid flow stop emergency device, casualties and marine pollution could be reduced. Many magnetic-type liquid spill stop emergency devices developed since 1904 have limitations, such as difficulties with installation and impossibility of use during sailing. This study demonstrated the applicability of a magnetic-type liquid spill stop emergency device through tests for water pressure and leakage, attachment, magnetic fields, and the generation of sparks. Results showed that the device can be applied to the ship’s side hull and bottom with a specified minimum diameter at a pressure depth of 1.0 kg/cm2 while sailing at a speed of 18 kts (9.26 m/s). If the distance from the device was at least approximately 750 mm, the magnetic field had no effect, and there was no risk of explosion due to sparks. A cost–benefit analysis based on the International Maritime Organization-approved guidelines for formal safety assessment confirmed the cost effectiveness of the device. This experimental study confirmed that the magnetic liquid stop emergency device is generally applicable to a ship’s hull.
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Oil Spill Monitoring of Shipborne Radar Image Features Using SVM and Local Adaptive Threshold. ALGORITHMS 2020. [DOI: 10.3390/a13030069] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the case of marine accidents, monitoring marine oil spills can provide an important basis for identifying liabilities and assessing the damage. Shipborne radar can ensure large-scale, real-time monitoring, in all weather, with high-resolution. It therefore has the potential for broad applications in oil spill monitoring. Considering the original gray-scale image from the shipborne radar acquired in the case of the Dalian 7.16 oil spill accident, a complete oil spill detection method is proposed. Firstly, the co-frequency interferences and speckles in the original image are eliminated by preprocessing. Secondly, the wave information is classified using a support vector machine (SVM), and the effective wave monitoring area is generated according to the gray distribution matrix. Finally, oil spills are detected by a local adaptive threshold and displayed on an electronic chart based on geographic information system (GIS). The results show that the SVM can extract the effective wave information from the original shipborne radar image, and the local adaptive threshold method has strong applicability for oil film segmentation. This method can provide a technical basis for real-time cleaning and liability determination in oil spill accidents.
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