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61.
62.
Glenn D. Aguilar Hiroyuki Yamamoto Takeo Koyama 《Journal of Marine Science and Technology》1996,1(3):138-148
The development of a parametric hull form design system utilizing combined knowledge-based and objectoriented methodologies,
approaches, and techniques is the major purpose of this research. One objective was the development of a powerful, intuitive,
and parameter-based hull definition system with a related hull definition advisory system that would provide useful and necessary
advice to the user. Object and knowledge modeling activities were conducted during the analysis and design stage to facilitate
the implementation of a hull design program and advisory system. The hull design system includes the generation of a geometric
model from a process of aggregating simple user-selected shapes representing different boundaries. Design involves the capability
to vary simple parameters such as entrance angles, length-breadth ratios, and radii to define local and general surface geometries.
Hydrostatic calculations are included for analysis; results are referred to an advisory system for evaluation and the determination
of the acceptability of parameters and analysis results. The advisory system includes a knowledge bases consisting of hull
form databases, results of the statistical analysis of data, design parameter constraints, and expert knowledge acquired from
designers, reference materials, and technical reports. Use of the design tool with the advisory system results in the rapid
generation of hull forms and associated design evaluations. Flexibility in decision making results from the separation of
the design system from the advisory system. The independence of the two systems allows for a wide range of user experience
with experts using the design tool with minimal reference to the advisory system. On the other hand, the expertise and knowledge
stored in the advisory system is fully available to inexperienced designers and users. 相似文献
63.
Kazuo?SuzukiEmail author Hisashi?Kai Shigetoshi?Kashiwabara 《Journal of Marine Science and Technology》2005,10(2):61-69
A hypothesis of the minimum energy of secondary flow, suggested by Bessho, is introduced here. According to this hypothesis, it can be expected that hull forms having frame lines with a minimum energy of secondary flow show less form drag. In the first part of this article, secondary flow energy is evaluated for the cases with and without a free-surface effect, and Bessho’s hypothesis is confirmed for practical hull forms. Then optimization methods for the stern hull form are suggested, in which a nonlinear optimization technique is introduced. Numerical examples are given for a practical tanker hull form and a practical container hull form. From these studies, the suggested optimization method can be confirmed as a simplified and practical design method to the select frame lines of stern hull forms. 相似文献
64.
65.
该文针对挂蓝施工对工期的制约和高速公路通行的影响,结合工程实践对挂篮工艺改为转体施工过程中的关键技术进行了研究。研究成果对以后的类似工程具有一定的借鉴意义。 相似文献
66.
随着测绘高新技术的广泛应用,城市道路纵横断面测量方法也有所改进,根据不同的地形状况、周边环境以及设计要求,可以选用不同的测绘手段,优质、快速、高效地获得纵横断面图的测量成果。该文结合工作实际,就如何合理地利用RTK测量的高新测绘手段,对城市道路改扩建工程的纵横断面进行测量,并对RTK测量方法及相应实施过程做一探索。 相似文献
67.
68.
从水动力学入手,阐述了舭龙骨的作用原理,针对常规散货船和油船,给出了舭龙骨的典型结构、构件尺寸及设计要求,并对舭龙骨的材质和各部分结构的细节要求以及安装和定位要求,尤其是对端部的要求进行了详细论述,并对舭龙骨的焊接要求作了深入研究。 相似文献
69.
70.
变截面圆柱形空腔覆盖层吸声系数的二维近似解 总被引:7,自引:0,他引:7
具有空腔周期性排列的粘弹性结构在水声工程中有着广泛的应用.将包含变截面圆柱形空腔周期性排列的吸声覆盖层的一个单元进行分段近似成多层圆柱管结构,并应用子域分割法在分段的接合界面处满足平均轴向位移和平均轴向应力连续,给出了变截面圆柱形空腔吸声覆盖层吸声系数的二维近似解.分析了高阶传播波和分段层数对吸声系数的影响,比较了不同空腔形状对覆盖层吸声性能的影响.研究结果表明,在一定频率范围内,主要是最低阶传播模式对吸声性能起作用,喇叭型空腔结构较圆柱型空腔结构吸声覆盖层的吸声性能更加优良.在覆盖层设计中,空腔的形状应有一个优化的过程. 相似文献