关于登机时间优化的新模式

旅客登机的时间优化问题一直困扰着国内外航班，航空公司希望提高飞机的利用率。采用双栈缓冲并行模式．将旅客分组模式改为组对，利用飞机通道作为临时缓冲区，一次安排一个旅客组对登机入座。仿真结果比当前最佳方案在登机时间上优化34．76％，对提高航空公司收益、改善服务质量和节约运营成本有着十分重要的应用价值。     

有源接收天线抗电磁干扰的设计与试验

通过分析有源接收天线在实际使用中可能遇到的电磁干扰环境,结合产品的特点和薄弱环节,采取相应的抗电磁干扰的设计措施,并对其进行相应的试验验证,在确保工作指标的同时,力求提高产品的抗电磁干扰能力,取得了一定的效果,对相关电子产品的设计具有一定的借鉴作用。     

电磁波在吸波涂层中的干涉现象

文摘为研究电磁波在吸波涂层中的干涉现象,选取了X型羰基铁粉吸收剂,采用同轴法测试了材料电磁参数,通过多次反射方法求解了X型吸波涂层在厚度为1/4波长时反射系数公式;另外,求解了不同厚度X-1型吸波涂层对频率为9.5 GHz平面电磁波反射系数公式,取公式前6项计算了反射系数Γ_a和反射率R_a。结果表明,多次反射波之间产生了干涉行为,发生了干涉相消现象。Γ_a、R_a分别与传输线方法计算的Γ和R的值非常接近,表明Γ_a和R_a可以近似代表X-1型吸波涂层对9.5 GHz电磁波的反射系数和反射率。当X-1型吸波涂层厚度小于1.9 mm或在3.2～6.6 mm时,第二反射波对第一反射波起到干涉相长作用,降低吸波性能,表明优选的吸波涂层厚度应该介于1.9～3.2 mm。     

Bolt insertion damage and mechanical behaviors investigation of CFRP/CFRP interference fit bolted joints

Interference fit has advantages in improving fatigue behaviors of composite bolted joints; however, interference fit bolt insertion tends to cause damages in laminates weakening joint mechanical properties. Therefore, an experimental study was conducted to investigate bolt insertion damages of Carbon Fiber Reinforced Polymer (CFRP)/CFRP interference fit bolted joints. Mechanical behaviors of joints were also evaluated experimentally under both quasi-static loads and cyclic loads. Scanning Electron Microscope (SEM) and high-resolution X-ray micro-CT scan were used to examine micro damages in laminates. Damage and failure behaviors of joints were characterized. The results demonstrated that the hole entrance in upper laminate and the laminate boundary near the hole wall were the most critical regions for damages during bolt insertions. However, the influence of those damages on quasi-static failure loads and fatigue failure modes of joints was minimal. Delamination and matrix cracking occurred first in laminates following fiber and matrix fracture in quasi-static tensile tests. Interference fit could improve the fatigue resistance of the laminate hole; however, the bolt seemed to suffer a more critical local fatigue loading condition. This paper can contribute to composite structure designs, especially in understanding damage and failure behaviors of composite bolted joints.     

非参数化迭代自适应SAR射频干扰抑制方法

合成孔径雷达（Synthetic Aperture Radar，SAR）的成像质量与图像解译精度会因为空间中存在的射频干扰（Radio Frequency Interference，RFI）而下降。本文在加权最小二乘迭代自适应算法的基础上，提出了非参数化的迭代自适应RFI抑制方法。该方法在成像处理前增加了对RFI的预检测环节，在初步检测出存在RFI的数据部分后只对存在RFI的数据进行SG（Savitsky-Golay，萨维茨基·戈莱）卷积平滑处理以提升对弱RFI的检测能力。利用带阻滤波器滤除存在干扰的频段后，使用迭代自适应处理在频谱中估计出被去除频段中的信号分量以获得期望的距离谱。与利用传统距离频率滤波方法进行RFI抑制相比，所提出的方法在图像细节保持方面效果更优，避免了因频谱不连续而导致的旁瓣增加，且运算效率更高。     

Interference mechanism and damage accumulation in high-speed cross scratches on hard brittle materials

Precision and low damage grinding of aviation optical elements can effectively improve the overall processing efficiency. The mechanism of high-speed cross scuffing of multiple abrasive particles has become an important factor affecting the forming quality of workpiece. Interaction of abrasive trajectory determines machined surface and subsurface morphology and damage.According to the relative motion trajectory of wear particles on the workpiece surface, a theoretical model of the trochoidal tra...     

内并联型进气道模态转换过程中流道间干扰特性研究

针对组合动力进气道模态转换过程中存在的流道间干扰现象,采用数值模拟方法对一典型内并联型进气道模态转换过程中高/低速流道间的干扰特性展开了深入研究。结果表明：在模态转换过程中,当低速流道结尾激波位于低速流道内部时,高速流道节流至一定程度都将对低速流道形成干扰。该干扰现象出现后,高/低速流道的流动耦合,两流道的流量分配也随之发生变化,甚至导致了进气道流场的失稳。仅当β/α=0.25时,高/低速流道间的干扰造成了进气道流场的失稳且失稳后的振荡流场会先后出现两个不同的发展时期：前一时期的振荡流场的振幅较大但频率较低,约为335Hz；后一时期的振荡流场的振幅较小但频率较高,约为880Hz。