择优比较法的水面舰艇反导作战通道性能分析

通过对影响水面舰艇反导作战通道性能的因素进行分析,构建了水面舰艇反导作战通道效能评价指标体系,建立了水面舰艇反导作战通道性能云模型,为水面舰艇反导作战通道性能评估提供了定量算法。水面舰艇反导作战效能的定量评估,对提高水面舰艇反导作战能力具有重要作用。     

Prediction of forming limit curve （FLC） for AI-Li alloy 2198-T3 sheet using different yield functions

The Forming Limit Curve （FLC） of the third generation aluminum-lithium （Al-Li） alloy 2198-T3 is measured by conducting a hemispherical dome test with specimens of different widths. The theoretical prediction of the FLC of 2198-T3 is based on the M-K theory utilizing respectively the von Mises, Hill＇48, Hosford and Barlat 89 yield functions, and the different predicted curves due to different yield functions are compared with the experimentally measured FLC of 2198-T3. The results show that though there are differences among the four predicted curves, yet they all agree well with the experimentally measured curve. In the area near the planar strain state, the predicted curves and experimentally measured curve are very close. The predicted curve based on the Hosford yield function is more accurate under the tension-compression strain states described in the left part of the FLC, while the accuracy is better for the predicted curve based on Hill＇48 yield function under the tension-tension strain states shown in the right part.     

Prediction of forming limit curve (FLC) for Al-Li alloy 2198-T3 sheet using different yield functions

The Forming Limit Curve (FLC) of the third generation aluminum-lithium (Al-Li) alloy 2198-T3 is measured by conducting a hemispherical dome test with specimens of different widths. The theoretical pred...     

用飞行员模型进行飞行品质自动评估技术研究

介绍了飞机的飞行品质评估典型任务,初步建立了飞行员行为特性数学模型以及飞行品质自动评定专家知识库,开发了基于试飞员模型的飞行品质评定软件的设计与实现;在六自由度动基座飞行模拟器上,针对某高教机电传飞控系统进行了飞行模拟器部分典型任务的飞行品质自动评估,其评估结果与飞行员评估结果基本吻合.该技术应用于飞控系统控制律设计、优化中,能提高设计效率,节约主观评定的时间,是客观飞行品质评定的有力补充.     

考虑危险天气的终端区动态容量评估

危险天气是影响航空运输飞行安全和导致航班延误的重要原因。随时间变化的危险天气决定了空域的动态容量。准确、及时的动态容量预测可以提高飞行安全性,也可以提高管制员的工作效率。在分析随时间变化的危险天气的基础上．提出用实时飞行受限区划设来表征危险天气：并给出了终端区空域网络图;应用最大流最小割理论找到受天气影响的终端区空域容量的瓶颈,建立了终端区动态容量评估模型;通过对某终端区危险天气进行算例分析．验证了模型的有效性和可行性。     

Optimization of structural parameters for elliptical cross-section spiral equal-channel extrusion dies based on grey theory

The elliptical cross-section spiral equal-channel extrusion (ECSEE) process is simulated by using Deform-3D finite element software. The ratio m of major-axis to minor-axis length for ellipse-cross-section, the torsion angle u, the round-ellipse cross-section transitional channel L1, the elliptical rotation cross-section transitional channel L2 and the ellipse-round cross-section transitional channel L3 are destined for the extrusion process parameters. The average effective strain eave on cross-section of blank, the deformation uniformity coefficient a and the value of maximum damage dmax are chosen to be the optimize indexes, and the virtual orthogonal experiment of L16 (45) is designed. The correlation degree of the process factors affecting eave, a and dmax is analyzed by the numerical simulation results using the weights and grey association model. The process parameters are optimized by introducing the grey situation decision theory and the ECSEE optimal combination of process parameters is obtained: u of 120 , m of 1.55, L1 of 7 mm, L2 of 10 mm, and L3 of 10 mm. Simulation and experimental results show that the material can be refined with the optimized structural parameters of die. Therefore, the optimization results are satisfactory.     

FM73M 胶膜及其与PMI 泡沫芯的胶接机理

采用DSC研究了不同升温速率下FM73M胶膜的固化反应特性,根据DSC曲线得到了胶膜的凝胶化温度和固化温度等工艺参数,建立了其固化动力学模型,确定胶膜的固化参数为(125±2)℃/90min.在此基础上,通过SEM研究了胶膜在PMI泡沫芯材内的分布以及界面结合状况(界面润温情况、气孔、缺陷),分析了胶膜与泡沫芯的胶接机理.     

浅论戏剧在外语教学中的应用

探讨了将戏剧教学应用于外语课堂教学的具体实施步骤与方法,并结合实际教学效果阐述了戏剧表演在外语课堂教学中的潜在功能。实践证明戏剧教学不仅有利于学生对语言知识的深度学习和可理解输入,而且可以提高学生学习的自主性和交际能力。它是第二语言掌握的有效方法之一。     

飞行管理系统性能计算策略分析

根据飞行管理系统机载软件对于性能计算的需求,提出了理论公式计算方法和插值计算方法,对于传统的理论公式计算方法进行了延迟时间数据分析.对以上两种计算方法分别从计算过程、软件工程、系统工程三个方面进行了分析和比较后得出,插值计算方法在机载飞行管理系统软件中是比较合理的方法.针对大型客机先进的航空电子系统,描述了以上两种计算方法分别在电子飞行包软件和飞行管理机载软件中的不同应用和联系.     

4D Lattice Flower Constellations

4D Lattice Flower Constellations is a new constellation design framework, based on the previous 2D and 3D Lattice theories of Flower Constellations, that focus on the generation of constellations whose satellites can have different semi-major axis and still present a constellation structure that is maintained during the dynamic of the system. This situation can arise when dealing with satellites with very different instruments, or when it is of interest to coordinate two different constellations. In that sense, 4D Lattice Flower Constellations constitutes the most general representation of the Flower Constellation formulation. In addition, the effects of the $J_2$ perturbation are taken into account in order to generate distributions that maintain their initial design configuration under this perturbation for longer periods of time with a low fuel budget. Finally, examples of application are presented, showing the possibilities in satellite constellation design of this new approach.