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岸边集装箱起重机自行式驱动小车存在小车易走偏缺陷,直接影响到桥机的装卸效率。用牵引式小车替代自行式小车是个可行的办法。分析了牵引式小车的价值和可行性。从5个重要环节介绍了小车牵引式改造的机械设计。介绍了小车牵引式改造的电气设计。进行了桥机自行式小车牵引式改造的,改造后小车运行平稳,提高了作业效率。 相似文献
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Cigdem Kadaifci Umut Asan Seyda Serdarasan Umut Arican 《Maritime Policy and Management》2019,46(2):237-256
The choice of the port or terminal to perform transshipment operations is a critical decision for container transportation companies (i.e. shipping line companies). This choice is not only affected by transshipment costs but also by the location, infrastructure, equipment, and technologies of the alternative terminals. In this study, a rule-based integrated multi-criteria group decision making approach is proposed in order to support such complex decision processes which involve substantial uncertainties and subjectivities. The proposed approach involves simple mathematics and provides a flexible modeling approach close to human reasoning that is able to consider uncertain information and relationships of arbitrary complexity. To prioritize the sub-criteria affecting the choice of the most appropriate terminal and to assess alternatives with respect to these sub-criteria, the Analytic Hierarchy Process (AHP) based on absolute measurement is used. Then, to determine the most appropriate terminal, a Fuzzy Rule-Based System is developed, which adopts the scores of criteria (i.e. the total scores of sub-criteria) obtained by AHP as input. In order to demonstrate the applicability and effectiveness of the proposed approach, an application is presented for the choice of the most appropriate container transshipment port in Turkey for a shipping line company. 相似文献
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A methodology for estimating extreme response statistics for marine structures, that takes both the long-term variability of the metocean environment and the short-term variability of response into account is presented. The proposed methodology uses Gaussian process regression to estimate parameters of the short-term response distribution, based on output from computationally expensive hydrodynamic simulations. We present an adaptive design strategy for sequential updating of the model, focusing on the metocean conditions that contribute the most to the long-term extreme. With this approach, only a limited number of hydrodynamic simulations are needed.The suggested approach is demonstrated on the problem of estimating the 25-year extreme vertical bending moment on a ship. We show that a relatively small number of iterations (full hydrodynamic simulations) are needed to converge toward the “exact” results obtained by running a large number of simulations covering the entire range of sea states.The results suggest that the proposed method can be used as an alternative to contour-based methods or other methods that consider a few sea states using accurate numerical simulations, with little or no added complexity or computational effort. 相似文献
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从我国内河航运开发缺乏资金入手 ,结合嘉陵江梯级渠化的以电养航问题 ,介绍了国内外以电养航这一有效手段的经验 ,着重分析了航电结合的效益和影响以电养航的因素 ,提出了以电养航的途径和建议 . 相似文献
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船用辅助鼓风机(以下简称风机)是在柴油机启动及低速工况为满足扫气系统的要求而附设的一种装置,这种风机与一般离心式通风机有明显不同,在外形尺寸上不仅要满足柴油机的安装要求,在性能上也必须达到给定的A点及B点空气流量和压力以满足柴油机起动及低负荷时对空气量的需求[1]。如何运用一种合理、高效的方法对试验数据的分析,是对风机的设计制造有着十分重要工程应用价值。因此通过运MATLAB可视化编程功能对辅助鼓风机测试数据进行最小二乘法曲线拟合,并对其拟合结果进行了分析, 拟合误差在3% 之内,得到了精准的风机的性能曲线。 相似文献
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