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1.
本文提出一种基于实时几何测距的船桥主动防撞方法。该方法对船的改动量甚微,仅需维持多项距离矩阵,通过告警逻辑矩阵进行展示与告警,能起到很好的船桥防撞提示效果。 相似文献
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为提升漆包线产品的技术水平与行业市场竞争力,使产品进入漆包线产品的高端市场,扩大公司漆包线新品种与技术储备,提升公司科研创新和新产品的研发能力,与客户合作开展对军工船舶发电机用特种漆包线的研制。根据特种漆包线的性能要求和关键技术,对其漆膜绝缘材料的选择、产品结构的设计与优化及研制的生产工艺技术进行探讨,研制出的特种漆包线通过对其性能考核,完全满足客户的各项性能指标要求。 相似文献
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In this paper, a new energy management algorithm has been suggested for the ships connected with alternative energies considering the smart electricity grid features. The algorithm focuses on the use of optimum energy source on the shipboard based on the priorities of authorities such as the most economic, environmental, or both criteria at the ports. The algorithm is performed in MATLAB, and several case studies are simulated to validate the results. The 5 maritime nations, which are at different regions: United States, Belgium, Turkey, China, and Australia, are taken into account in the case studies. The actual data of a bulk carrier ship have been used to achieve tangible results in the simulations. The results of the case studies are compared to determine the changes of energy cost and released emission to meet demand of electricity on the ships. Capital cost of the proposed concept is also given to make an economic evaluation. The results show that the ship energy management algorithm provides the significant economic and environmental advantages. This paper aims to contribute to the importance of the ships in the smart electricity grid concept for the maritime and electricity sector representatives. 相似文献
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冰载荷是影响船舶冰区航行期间结构安全的重要环境载荷。船舶的冰压监测通常采用应变传感器,合理地布放传感器是识别冰载荷的基础。通过对比船体外板结构试验中的冲击载荷和不同测试方案下的应变信号,确定了最佳应变传感器布放方案;采用Green核函数方法建立了船体外板结构应变冲击载荷间的响应关系,并对采集信号在噪声影响下反演的不适定性进行了分析;采用Tikhonov正则化方法克服了载荷反演过程中出现的数值不稳定问题;最后将试验中的响应用到载荷识别分析中,反演的载荷可以较为准确地反映冲击载荷的时域特征并且载荷识别精度良好。 相似文献
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目前,影响海洋工程和船舶焊接结构质量的重要影响因素之一就是焊接变形,其产生的根本原因就是在焊接过程中因结构体受热不均、热梯度、残余应力等。基于此,本文对焊接变形预测的理论发展进程及其相关理论内涵进行详细阐述,并对基于神经网络的新型焊接变形预测理论的研究发展简单概述。 相似文献
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Radial size estimation using radar high-resolution range profiles(HRRPs) and heading angle estimation are the main means for ship classification.The classification ability is closely related to the range resolution of the radar,precision of radial size estimation,and prior distribution of ship lengths in different offshore areas.We collected the AIS information on about 30 000 ships and their lengths in the four offshore areas of China in the ship information net of China.By fitting the data of ship lengths in each offshore area,it is found that the Weibull distributions provide good-of-fitness to the ship lengths and the parameters in individual area are rather different.Based on the prior distributions of ship lengths,we derived the quantitative relationship between the correct classification probability of big-moderate-small ships and the estimate error of ship radial size.The results indicate that the condition for the big-moderate-small correct classification probability in the offshore areas of China to be up to 90% is that the estimate errors of the ship radial size estimates falls into the interval(-12.67 m,9.41 m) when the heading angle of the ship is between ±75 degrees. 相似文献
9.
《International Journal of Hydrogen Energy》2022,47(63):27166-27176
The maritime industry has entered its pathway of decarbonization. To achieve the IMO's ambitious goals of an absolute emissions reduction of 50% by 2050, and a 70% carbon intensity reduction by 2050 compared to the 2008 level, various options for the adoption of technologies and alternative fuels are considered by the market stakeholders.Ammonia, one of the most promising alternative marine fuels has long been considered to reduce carbon emissions. And solid oxide fuel cell is expected to transform ship propulsion technology in the future due to its high utilization of fuels. In this paper, a feasibility study is performed to assess the application of an ammonia cracker-integrated solid oxide fuel cell (hereafter as Ammonia SOFC) system on an ocean-going vessel through a detailed CAPEX, FuelEX, OPEX, Carbon tax, and carbon emission analysis. Comparison is made with direct ammonia, LNG and conventional fuels fired heat engines. The result concludes that it can be economically viable to apply to deep-sea shipping, compared to other marine fuels and propulsion technologies. 相似文献
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