简易U型弯曲模设计

本文介绍了一种简易的U型弯曲模具的设计方法,具有结构简单、制造容易、节约材料、重量轻的特点,在小批量生产中有借鉴意义。     

三元二次样条函数及其计算（Ⅰ）——高维数据拟合

半节点二次样条是Ｃ１类连续的，其二阶导函数是阶梯函数，在半节点处产生跳跃。鉴于此，本文利用最小二乘法，获得了一种半节点二次插值样条边界条件确定方法，该方法可以保证二次插值样条在半节点处二阶导数的变化最小，这相当于保证了曲率的变化最小。为了适应四维数据插值的需要，给出了三元二次插值样条的定义及基样条表示，提出了一种边界条件，证明了其存在唯一性。最后把二次插值样条边界条件确定方法推广到三元二次插值样条上去，获得了三元二次插值样条边界条件的确定方法。该方法的意义是，可以直接从插值条件获得边界条件，从而克服了多元样条边界条件难以确定的困难     

卫星通信中的星上交换技术

卫星通信网络发展交换功能是为了适应大容量信息传输的要求。本文介绍了两种应用于卫星通信中的交换技术：卫星异步传输模式(ATM)交换和卫星交换/码分多址(SS／CDMA)。它们各具特色，前者将成熟的ATM交换技术引进卫星交换；而后者是一种新兴的交换概念，为具有交换功能的卫星的最终实用化提供了理论基础。     

PROPAGATION CHARACTERISTICS OF A CIRCULAR MULTILAYER CHIRAL DIELECTRIC WAVEGUIDE

ＰＲＯＰＡＧＡＴＩＯＮＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＡＣＩＲＣＵＬＡＲＭＵＬＴＩＬＡＹＥＲＣＨＩＲＡＬＤＩＥＬＥＣＴＲＩＣＷＡＶＥＧＵＩＤＥＨｕａＲｏｎｇｘｉ；ＳｈｅｎＺｈｏｎｇｘｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｏｎｉｃＥｎｇｉｎｅ...     

模板类零件孔系的计算机辅助设计

本文介绍子模具设计中的模板类零件中的孔系的计算机辅助设计，对于位置参数相同而结构和尺寸不同的孔系零件，可以由一个孔位置定义文件设计所有的零件。零件用这种方法可以很方便地提高设计速度和设计质量。     

总剂量探测技术的空间应用

空间辐射对飞行器可造成辐射损伤甚至失效,对航天员的生命健康安全存在着威胁。随着航天活动的深入,对空间辐射探测技术的发展提出了更高的要求。通过辐射敏感场效应晶体管（RADFET）探测技术设计研制了总剂量探测器,介绍了探测器的设计原理和测试数据分析,以及研究发展方向和空间应用展望。     

Robust optimization of aircraft weapon delivery trajectory using probability collectives and meta-modeling

 Conventional trajectory optimization techniques have been challenged by their inability to handle threats with irregular shapes and the tendency to be sensitive to control variations of aircraft. Aiming to overcome these difficulties, this paper presents an alternative approach for trajectory optimization, where the problem is formulated into a parametric optimization of the maneuver variables under a tactics template framework. To reduce the size of the problem, global sensitivity analysis (GSA) is performed to identify the less-influential maneuver variables. The probability collectives (PC) algorithm, which is well-suited to discrete and discontinuous optimization, is applied to solve the trajectory optimization problem. The robustness of the trajectory is assessed through multiple sampling around the chosen values of the maneuver variables. Meta-models based on radius basis function (RBF) are created for evaluations of the means and deviations of the problem objectives and constraints. To guarantee the approximation accuracy, the meta-models are adaptively updated during optimization. The proposed approach is demonstrated on a typical airground attack mission scenario. Results reveal that the proposed approach is capable of generating robust and optimal trajectories with both accuracy and efficiency.     

酸处理对纤维表面偶联剂吸附量的影响

对玄武岩纤维表面进行酸刻蚀处理并浸泡铝锆偶联剂溶液,探讨酸浓度、酸处理时间和偶联剂浓度对玄武岩纤维表面偶联剂吸附量的影响.通过FTIR和XPS分别定性和定量地分析纤维表面官能团及C、O、Si、Zr元素的变化来表征纤维表面偶联剂的吸附量.结果表明:三因素对纤维表面偶联剂吸附量的影响程度由大到小依次为酸浓度、偶联剂浓度和酸处理时间.随着酸浓度升高,纤维表面偶联剂吸附量呈现出先减小后增大的趋势;酸处理时间延长和偶联剂浓度增大,纤维表面偶联剂的吸附量呈现逐渐增大的趋势.当酸浓度为3 mol/L、处理1.5h、偶联剂浓度为3wt％时,偶联剂在玄武岩纤维表面的吸附量最大.     

Experimental research in rotating wedge-shaped cooling channel with multiple non-equant holes lateral inlet

The heat transfer in a novel smooth wedge-shaped cooling channel with lateral ejection of turbine blade trailing edge is experimentally investigated in both non-rotating and rotating cases. Beside the conventional inlet at the bottom of the channel, an extra coolant injection from 8 lateral non-equant holes is introduced to improve the overall heat transfer. The total mass flow rate ratio (lateral mass flow rate/total mass flow rate) varies from 0 to 1.0. The major inlet Reynolds number and rotation number respectively vary from 10000 to 20000 and from 0 to 1.16. Experimental results show that the lateral inlet decreases local bulk temperature and increases local heat transfer at the middle and the top of the static channel. In rotating cases, the lateral inlet notably improves the heat transfer at the high-radius half channel and compensates the negative effects induced by the rotation. Both intensity and uniformity of heat transfer inside the channel are enhanced while flow resistance decreases with proper mass flow rate ratio of coolant from two inlets. The most satisfactory total mass flow rate ratio is around 2/3. This new structural style of cooling channel has huge potential and provides new direction of heat transfer of turbine blade trailing edge.     

空间太阳能电站姿态运动-结构振动耦合建模与分析

针对多旋转关节空间太阳能电站构型，利用基于能量等效原理的连续体等效方法将其等效为柔性梁模型，并考虑重力梯度影响，建立了姿态运动与结构振动的耦合动力学模型；结合Runge-Kutta 法和Newmark法的优点，提出了适用于求解姿态运动与结构振动耦合动力学方程的改进算法，相比于经典Runge-Kutta 法大幅提高了效率；利用改进算法得到了不同参数下的动力学响应。在此基础上，推导了结构振动量级随结构尺寸的六次方量级增加的规律，仿真结果表明尺寸过大引发不稳定现象；分析了姿态运动和重力梯度对结构振动频率和振幅的影响；发现了姿态运动周期受结构柔性影响而增大的现象，这种现象在低轨以及大初始姿态角下影响更为明显。