HLA框架下舰艇CGF的总体方案及其实现

计算机仿真技术的发展以及提高综合训练真实度的需求使得计算机生成兵力(computer generated force，CGF)在军事训练领域得到了高度重视和应用。为了在潜艇综合训练仿真系统中使用舰艇CGF，必须仿真海洋复杂环境下舰艇实体的一整套作战过程。为了提高舰艇CGF的重用性和可扩展性，采用了与HLA兼容的体系结构。舰艇CGF被作为HLA框架中的一个联邦成员，并考虑到了在实际作战中的实体行为。     

平头压痕试验结合有限元法确定材料蠕变参数

对LY12CZ材料进行了压痕蠕变和单轴拉伸蠕变试验.通过有限元方法,对压痕蠕变试验进行了模拟.通过压痕蠕变试验结合有限元的方法,确定了材料的蠕变参数,其中应力指数nmI=nI=4.894,蠕变常数c'mI=5.780×10-19s-1MPan.从以上的研究中发现,由单轴蠕变试验(nm和cm)和压痕蠕变试验结合有限元(n'mI和c'mI)分别得出的蠕变参数是一致的,而且最重要的是压痕蠕变指数与材料的蠕变指数是相等的,nm=nI.     

镍基单晶合金筏化规律及蠕变持久寿命模型在复杂应力状态下的考核

利用双剪切蠕变试样在受剪切区的筏化试验结果和不同晶体取向试样的蠕变持久寿命试验结果，对镍基单晶合金的蠕变筏化预测模型和蠕变持久寿命模型进行考核，证实此2个模型的合理性。     

飞机翼梁结构强度可靠性灵敏度分析

将翼梁结构中的所有结构尺寸、载荷大小、材料参数都当作结构设计时确定的具体值,对飞机翼梁结构进行强度分析,由强度分析可知,翼梁上的应力分布以及最大应力位置,可校核翼梁结构是否满足强度设计要求;考虑翼梁上下缘条、腹板1～5、翼肋1～5等厚度尺寸,由于加工、设计公差等造成实际翼梁结构尺寸的分散性,将这12个厚度参数作为正态分布的基本变量,对翼梁结构强度进行可靠性分析,并对基本变量分布参数的灵敏度进行分析;采用不含交叉项的二次响应面法对翼梁结构的强度可靠度进行分析,得到基本变量均为正态分布时翼梁结构强度的可靠度;并对基本变量参数影响结构可靠度的灵敏度进行分析,发现影响翼梁可靠度的主要因素是:腹板1、腹板5和下缘条的厚度分布参数.     

State-of-the-art on theories and applications of cable-driven parallel robots

Cable-driven parallel robot (CDPR) is a type of high-performance robot that integrates cable-driven kinematic chains and parallel mechanism theory. It inherits the high dynamics and heavy load capacities of the parallel mechanism and significantly improves the workspace, cost and energy efficiency simultaneously. As a result, CDPRs have had irreplaceable roles in industrial and technological fields, such as astronomy, aerospace, logistics, simulators, and rehabilitation. CDPRs follow the cutting-edge trend of rigid–flexible fusion, reflect advanced lightweight design concepts, and have become a frontier topic in robotics research. This paper summarizes the kernel theories and developments of CDPRs, covering configuration design, cable-force distribution, workspace and stiffness, performance evaluation, optimization, and motion control. Kinematic modeling, workspace analysis, and cable-force solution are illustrated. Stiffness and dynamic modeling methods are discussed. To further promote the development, researchers should strengthen the investigation in configuration innovation, rapid calculation of workspace, performance evaluation, stiffness control, and rigid–flexible coupling dynamics. In addition, engineering problems such as cable materials, reliability design, and a unified control framework require attention.     

Influence of Grain Boundary on Fatigue Behavior of Ni-base Bicrystals

The influence of the grain boundary on the fatigue behavior was studied by two three-point-bending (TPB) specimens. One TPB specimen was named Bicrystal 1, whose pre-crack was along the grain boundary and the applied load paralleled to pre-crack direction, while the other TPB specimen was named Bicrystal 2, whose the pre-crack was perpendicular to the grain boundary and the applied load paralleled also to the pre-crack. It was found that the rate of the fatigue crack growth of Bicrystal 1 was about a tenfold higher than that of Bicrystal 2. The fatigue behavior of Bicrystal 2 specimens was dependent on the distance between the crack tip and grain boundary. The crack growth rate was highest when the crack tip was at a critical distance to the grain boundary, while the rate was the lowest when the crack tip reached grain boundary. After the crack was over the grain boundary, the crack growth rate increased. The crystallographic finite element method was applied to analyze the stress and strain structure ahead     

语音预测的LMS方法及性能分析

传统的语音处理技术忽视了语音中可能存在的非线性结构,因而限制了处理能力的进一步提高,通过语音预测模型的基于最小均方误差的自适应预测分析,讨论了数据集平均对LMS算法瞬态特征的影响和步长对均方误差的影响。通过LMS滤波器的过渡特性及其学习曲线的实验仿真,证实了小步长理论的结果与实验结果之间的紧密一致。     

单晶冷却叶片气膜孔附近的蠕变持久寿命分析

从单晶冷却叶片中取出一个包含气膜孔的单胞模型,在流体和传热分析的基础上,给出了含气膜孔模型的气动载荷和温度分布.建立了一个晶体有限元模型,根据不同取向的蠕变参数,对单胞模型进行蠕变及持久寿命分析.结果表明,气膜孔附近存在一个明显的温度梯度.温度梯度使模型的位移和等效应力的分布产生梯度.温度梯度对气膜孔周围蠕变持久寿命的影响比较大,且对[111]取向的蠕变持久寿命的影响要大于[001]方向.     

复杂应力状态下镍基单晶合金低周疲劳寿命预测模型

镍基单晶合金的低周疲劳（ＬＣＦ）晶体取向相关性和其弹塑性的晶体取向相关性有密切关系,基于所建晶体取向各向异性弹塑性晶体滑移模型,本文推导了复杂应力状态下镍基单晶合金低周疲劳寿命预测模型,结论为ＬＣＦ寿命与修正的滑移应变呈指数关系。在详细分析薄壁圆筒试样受拉－扭载荷下应力应变分布规律的基础上,利用不同拉－扭载茶下的低周疲劳寿命数据,对本文所提模型进行了成功的考核。     

（E）-3，5，4’-三羟基联苯乙烯的NMR谱分析

本工作利用 包括1H NMR、APT（Attached proton Test ）、HMBC等NMR技术对（E）-.,5,4’-三羟基联苯乙烯的NMR谱学特征进行分析。该化合物结构简单,但高度对称,所含质子个数相对较少,结构解析有一定的难度。本工作对实验谱的内含信息进行 挖掘,并对其谱学特征（包括某些实验的“缺陷”）进行分析,最终完成该化合物的NMR结构解析