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71.
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
72.
船体破损后外载荷与船体极限弯矩 总被引:8,自引:0,他引:8
基于船舶不沉性理论,运用符拉索夫抗沉性计算法确定船舶破损后浮态参数之后,作出波浪上船舶破损浮力曲线,继而计算了波浪弯矩和波浪剪力;并用非对称梁弯曲理论建立了破损模型,将外载荷与破口联系在一起研究了破损船舶极限弯矩,通过实例计算得出了预想结果。 相似文献
73.
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
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基于FRIENDSHIP系统提出改进的Lackenby变换方法,改进的Lackenby变换使用B样条曲线,而不是采用传统的多项式进行船型变换。经过CFD计算验证,效果较好。 相似文献
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79.
船体零件智能优化排样系统的设计研究 总被引:1,自引:0,他引:1
针对船体零件的排样问题,开发了基于智能算法的板材套料优化排样系统。该系统采用粒子群算法,并将免疫记忆和浓度机制引入算法提高了零件的排序优化速度。通过零件图形信息数据库管理模块和排样解码算法,实现图形的输入和编码、定位排放和正交靠接及自动计算生成最优排样结果。排样实例表明了该系统具有良好界面和人机交互功能,且有效提高了排样自动化程度和材料利用率。 相似文献
80.