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文章首先对含中心裂纹有限加筋板应力强度因子的计算结果进行了对比分析,然后通过对结点位移的解析解和有限单元法中的计算表达式的分析,提出一个用于评估应力强度因子计算精度的参数,并通过算例和文献结论分析说明该参数是一个计算简便的、有工程实际意义的参数.可以用于加筋板应力强度因子的计算精度评估. 相似文献
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操纵性相关性分析一直以来是受到国内外学者的关注,但是由于其复杂性,至今未能很好地解决.目前,模型试验的数据往往是直接预报到实船的操纵性能,这有可能导致很大的偏差,影响船舶的航行安全.本文针对育鲲轮,进行了实船试验与模型试验的相关性分析.首先进行了实船回转试验和z形试验,测试了该船的操纵性.通过试验数据分析获得了纵距、横距、战术直径、回转直径、超越角等操纵性特征参数,试验过程中也进行了船舶姿态,如纵、横摇以及主机功率的测试.通过实船回转试验发现,主机功率比直航时增大了大约15%,这给船舶设计提供了参考.然后,采用6m长左右的模型也进行了相同试验的测试,电机转速与实船主机转速相似,且一直保持不变.最后,分析比较了模型所测数据与实船数据,发现特征参数误差基本都在10%以内.说明模型长度、螺旋桨的模拟等模型试验方案基本可行. 相似文献
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阐述了自适应模糊推理系统(Adaptive Network—based Fuzzy Inference System,ANFIS)网络,提出了水运货运量预测的ANFIS网络预测模型.以MATLAB为工具,以1985~2001年我国水运货运量为训练样本;2002年我国水运货运量为校验样本,对网络进行训练后,预测了2003~2010年我国水运货运量.估算结果表明,同BP神经网络模型相比,此模型具有更高的准确性. 相似文献
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Ship maneuverability, in the field of ship engineering, is often predicted by maneuvering motion group MMG) mathematical model. Then it is necessary to determine hydrodynamic coefficients and interaction force coefficients of the model. Based on the data of free running model test, the problem for obtaining these coefficients is called inverse one. For the inverse problem, ill-oposedness is inherent, nonlinearity and great computation happen,and the computation is also insensitive, unstable and time-consuming. In the paper, a regnlarization method is introduced to solve ill-posed problem and genetic algorithm is used for nonlinear motion of ship maneuvering. In addition, the immunity is applied to solve the prematurity, to promote the global searching ability and to increase the converging speed. The combination of regnlarization method and immune genetic algorithm(RIGA) applied in MMG mathematical model, showed rapid converging speed and good stability. 相似文献
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基于Visual Basic 6.0的Auto CAD图形数据交互技术 总被引:2,自引:1,他引:1
介绍了利用VisualBasic 6.0的强大功能,对AutoCAD进行二次开发,提取图形对象数据,来修改图形对象.此方法运用于船舶设计中,通过修改船体型线来满足设计者的要求.同时作者也提出了该方法对船舶性能计算的实用性,为人机交互式地进行船舶设计提供了简易、快捷、有效的方法和途径. 相似文献
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It is very difficult,for the component-type ship mathematical model,to estimate the interaction force coefficients among the hull,propeller and rudder. Some coefficients such as wake fraction and flow straightening coefficient were studied from the model tests in diffierent loading conditions and the normal force of rudder was tested in captive model tests to obtain the coefficients. From these results of the tests,the flow straightening coefficients increase with the increase of trims or drafts. Similarly,... 相似文献