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Container vessels navigate among the world's ports, frequently passing through narrow and congested waters. Due to the many layers of containers on a container vessel's decks, it is difficult for the crew to be aware of all fishing vessels and other obstacles in a container vessel's radar observation blind zone. This greatly increases the risk of collisions and other accidents. Given such great challenges to safe navigation and safety management with container vessels, their security risks are severe. An effective visual monitoring system can improve the safety of the water area surrounding container vessel by eliminating a vessel's observation blind zone, providing an effective safety measure for vessels navigating fishing zones and other troublesome areas. The system has other functions, such as accident recording, ship security, and monitoring of loading and unloading operations, thus ensuring the ship operates safely. Six months' trial operation showed that the system facilitates safe navigation of container vessels. 相似文献
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The increasing scale and complexity of 3D scene design work urge an efficient way to understand the design in multi-disciplinary
team and exploit the experiences and underlying knowledge in previous works for reuse. However the previous researches lack
of concerning on relationship maintaining and design reuse in knowledge level. We propose a novel semantic driven design reuse
system, including a property computation algorithm that enables our system to compute the properties while modeling process
to maintain the semantic consistency, and a vertex statics based algorithm that enables the system to recognize scene design
pattern as universal semantic model for the same type of scenes. With the universal semantic model, the system conducts the
modeling process of future design works by suggestions and constraints on operation. The proposed framework empowers the reuse
of 3D scene design on both model level and knowledge level. 相似文献
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为研究发动机低温和常温环境下EGR冷却器积碳的差异性,以两台相同型号和配置的国Ⅵ柴油机为试验对象,设计了常温 (25 ℃)、低温 (-8 ℃) 两种不同环境温度下EGR积碳发动机896 h台架试验。结果表明,低温环境下EGR冷却器的积碳程度和速度均大于常温,换热效率下降幅度和压力损失增大幅度均大于常温;EGR冷却器积碳导致的换热效率下降是试验后NOx、PM排放增大,HC排放减小的主要原因,冷却器换热效率下降越严重排放变化越明显;HC的冷凝会导致废气中 HC浓度的下降,排气温度和冷却介质的冷却能力都对 EGR管道内 HC浓度的下降有影响,但是冷却介质的冷却能力起主导作用。 相似文献