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91.
一种舰艇编队区域防空效能评估方法 总被引:1,自引:1,他引:0
舰艇编队的区域防空作战是一个复杂问题,而对其效能评估又涉及大量难以量化的因素,且因素间存在多重相关性。主成分分析正是适宜解决这一难题的方法论,它可通过将相关性很高的变量转化成彼此独立或不相关的变量,有效降低维度,最终达到数据化简、揭示变量间的关系和进行数据解释的目的。建立了舰艇编队区域防空作战效能评估模型,运用主成分分析法对该模型的多项指标进行综合聚集,最后以编队区域防空作战训练评估为例,验证该模型方法的科学性与可行性。 相似文献
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Rectangular tiles can be laid on a ship’s hull for protection, but the sides of the tiles must be adjusted so adjacent tiles
will conform to the curvature of the hull. A method for laying tiles along a reference line was proposed, and an allowable
range of displacement for the four vertices of the tile was determined. Deformations of each tile on a specific reference
line were then obtained. It was found that the least deformation was required when the tiles were laid parallel to a line
with the least curvature. After calculating the mean curvature on the surface, the surface was divided into three layout areas.
A set of discrete points following the least deformation of the principal curvatures was obtained. A NURBS interpolation curve
was then plotted as the reference line for laying tiles. The optimum size of the tiles was obtained, given the allowable maximum
deformation condition. This minimized the number of bolts and the amount of stuffing. A typical aft hull section was selected
and divided into three layout areas based on the distribution of curvature. The optimum sizes of rectangular tiles were obtained
for every layout area and they were then laid on the surface. In this way the layout of the rectangular tiles could be plotted. 相似文献
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This article presents a method of numerical expression to draw ship hull forms. Recent developments in research into ship hull optimization need a method to express ship hull form as precisely as possible with a small number of design parameters. This method is based on a combination of the Fourier–sine series expansion and nonuniform B-spline (NUBS) interpolation. The merit of the combination is that it removes the wiggles which are often found when generating a rectangular-type curve, such as the midship section of tanker ship, with a simple Fourier series expansion. Here, the procedure is explained, and then a tanker ship hull is generated. Through the discussion, we show the effectiveness of the method. 相似文献
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水火弯板模拟方法研究 总被引:5,自引:0,他引:5
本文简述了水火弯板模拟方法研究内容;以帆型板为例,介绍了两种复杂曲面成形必需局部收缩量的计算方法;应用数理统计和逐步回归原理,建立了最大收缩长度和影响参数的数学模型,并进行了模型的检验;提出了数学模型的实验修正方法和工艺参数优化设计方法。 相似文献
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结合斧头首概念(AXE Bow Concept,ABC),介绍了45m高速海洋平台供应船的型线设计。 相似文献
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