两共线半无限裂纹板的弯曲问题

研究两共线半无限裂纹板的弯曲问题，应用Ｓｃｈｗａｒｚ对称原理和复应力函数的奇异性分析，将问题化为全纯函数的“联结问题”，求得了问题的封闭形式解和应力强度因子公式，并通过与有限元结果比较，说明了它们的工程实用价值。     

Local clouds: Distribution, density and kinematics through ground-based and HST spectroscopy

The distribution, kinematics and physical properties of the interstellar matter surrounding the Sun can be inferred from ground-based and UV spectroscopic observations. On a 200 pc scale the local interstellar matter appears inhomogeneous and asymmetric. Although it generally flows towards the lower density region, it is composed of numerous small components a few parsecs in size with slightly different velocities. On a smaller scale the extent and the nature of the Local Cloud which flows over the Sun are discussed based on HST-GHRS observations of nearby stars.     

低压下V形火焰稳定器后回流区流动特性研究

本文用双通道热线风速仪对低压下V形火焰稳定器后回流区流动特性进行了实验研究,获得了局部平均速度、素流强度、雷诺应力等参数的分布情况。实验表明,与常压比较,低压下回流区范围有所缩小,回流流量相对降低,雷诺应力普遍下降,紊流尺度略有增加,从流体力学方面为分析低压下稳定器的燃烧性能提供了新的依据。     

特种通用飞机改装流程及探讨

通过了解特种通用飞机改装流程及适航审批各阶段应开展的工作,对特种通用飞机改装过程中的注意事项进行了探讨,并给出了其适航审批过程中的合理化建议。     

机械力学性能拉伸试验的拉伸速度研究

在室温机械力学性能拉伸试验中，在满足其它规定条件的前提下，拉伸速度是一个关键的因素。分析了拉伸速度与力学性能的关系、原理；提出控制拉伸速度的方法与计算公式及要求，有效地提高了产品质量。     

用奇异有限元法计算正交各向异性复合材料平面断裂的应力强度因子

将复合材料平板视为正交各向异性平板，把正交各向异性平板裂纹顶点附近的位移展开式迭加在一般的等参数单元上，建立了用于复合材料平板应力强度因子计算的奇异元。并以所做出的公式，对正交各向异性板含单边裂纹和双边裂纹问题进行了计算分析，取得了较好的效果。     

Experimental method for and theoretical research on defect tolerance of fixed plate based on damage mechanics

An experimental method and a theoretical analysis based on continuum damage mechan-ics are applied for the defects tolerance of fixed plate. The defects type studied in this article is scratch, which i...     

Experimental method for and defect tolerance of fixed plate theoretical research on based on damage mechanics

An experimental method and a theoretical analysis based on continuum damage mechan- ics are applied for the defects tolerance of fixed plate. The defects type studied in this article is scratch, which is considered a typical defect on fixed plate according to the engineering practice. The general approach to the defects tolerance analysis of scratched fixed plate is presented. The method of fatigue life prediction for standard notched specimens has been established on the basis of continuum damage mechanics. For the purpose of obtaining the influence law of fatigue life in consequence of scratches, fatigue experiments of standard notched specimens and scratched specimens have been done. Evalu- ation of the fatigue life of scratched fixed plate has been carried out. And the value of scratch defects permissible to the condition of safety service life has been worked out. According to the results of the- oretical calculations, the fatigue experiment of scratched fixed plate has been performed. The outcome shows that the theoretical prediction tallies with the experimental results.     

二维系统一般模型的正实控制

本文研究的是二维系统一般模型的正实控制。本文的目的是针对该模型,设计一个状态反馈控制器,使得闭环系统是稳定的并且闭环传递函数是延展严格正实的,所得到的解是通过线性矩阵不等式给出,通过解决该线性矩阵不等式可获得期待的状态反馈控制器。最后,我们提供了一个数值算例来验证提到方法的有效性。