高氯酸铵／硝胺推进剂冲击感度研究

对高氯酸铵/硝胺推进剂冲击感度的研究结果表明,在丁羟推进剂中加入黑索今(RDX),可使其冲击感度增大,但RDX加入量增大,则其冲击感度增大的幅度却逐渐下降。研究还表明铝粉对推进剂的冲击感度也有影响。     

Transputer在连续系统并行仿真中的应用研究

本文介绍了一种新型的VLSI单片处理机,并通过实例讨论了用Transputer构成的多处理机系统在连续系统并行仿真中的应用。     

同步卫星姿态控制系统稳定性分析

本文介绍苏联“萤光屏”系列地球同步卫星的姿态控制系统以及在稳态运行时姿态控制系统俯仰通道的稳定性分析,分析中考虑了太阳帆板的挠性。飞行实验表明,文中所介绍的方法在工程设计中是简单可行的。     

多孔超高燃速推进剂的燃烧理论

概述了有关多孔透气性超高燃速推进剂的代表性燃烧理论,其包括对流燃烧理论、两相流燃烧理论和非均一燃烧理论,介绍了它们的基本观点和主要结果,指出了彼此间的差异。     

Neuroimmune response and sleep studies after whole body irradiation with high-LET particles

In order to investigate the biological effects of galactic rays on astronaut cerebral functions after space flight, mice were exposed to different heavy ions (HZE) in whole-body conditions at doses comparable to the galactic flux: ¹²C, ¹⁶O and ²⁰Ne (95 MeV/u, at 42–76 mGy). Animals were also exposed to 42 mGy of ⁶⁰Co radiation for comparison with HZE. The neuroimmune response, evaluated by interleukin-1 (IL-1) measurement, showed that this cytokine was produced 3 h after irradiation by ¹⁶O or ⁶⁰Co. In contrast, neither ¹²C (56.7 mGy) nor ²⁰Ne (76 mGy) induced IL-1 production. However, immunohistochemical staining of ¹²C-irradiated mouse brain tissue showed 2 months later a marked inflammatory reaction in the hippocampus and a diffuse response in parenchyma. Sleep studies were realized before and after exposure to 42 mGy of ¹⁶O and 76 mGy of ²⁰Ne: only the ²⁰Ne radiation displayed a small effect. A slight decrease in paradoxical sleep, corresponding to a reduction in the number of episodes of paradoxical sleep, was manifested between 8 and 22 days after exposure. Exposure to ¹²C and ¹⁶O induced no changes either in cellularity of spleen or thymus, or in caspase 3 activity (as much as four months after irradiation). Taken together, these data indicate that the CNS could be sensitive to heavy ions and that responses to HZE impact depend on the nature of the particle, the dose threshold and the time delay to develop biological processes. Differences in responses to different HZE highlight the complex biological phenomena to which astronauts are submitted during space flight.     

逆合成孔径雷达综合对抗策略分析

针对ISAR成像特点,提出了对ISAR在成像过程中容易受干扰的不同环节进行干扰的综合对抗策略,可以有效地降低ISAR二维处理增益的优势,干扰ISAR对目标的成像与识别效果。     

基于VC++和MATLAB混合编程的虚拟仪器技术

介绍了一种以数据采集卡为底层硬件,基于VC 界面和MATLAB数据处理混合编程开发的虚拟仪器技术,并将它用于火箭发动机推进剂药柱粘弹性性能测试。结果表明,此方法开发周期短,效率高,开发的测试系统使用方便。     

RBFs-MSA Hybrid Method for Mesh Deformation

Simulating unsteady flow phenomena involving moving boundaries is a challenging task,one key requirement of which is a reliable and fast algorithm to deform the computational mesh.Radial basis functions(RBFs) interpolation is a very simple and robust method to deform the mesh.However,the number of operations and the requirement of memory storage will be increased rapidly as the number of grid nodes increases,which limits the application of RBFs to three-dimensional(3D) moving mesh.Moving submesh approach(MSA) is an efficient method,but its robustness depends on the method used to deform the background mesh.A hybrid method which combines the benefits of MSA and RBFs interpolation,which is called RBFs-MSA,has been presented.This hybrid method is proved to be robust and efficient via several numerical examples.From the aspect of the quality of deforming meshes,this hybrid method is comparable with the RBFs interpolation;from the aspect of computing efficiency,one test case shows that RBFs-MSA is about two orders of magnitude faster than RBFs interpolation.For these benefits of RBFs-MSA,the new method is suitable for unsteady flow simulation which refers to boundaries movement.     

Multi-resolution Analysis of Density Fluctuation of Coherent Structures About Supersonic Flow over VG

The density field around a vortex generator (VG) in supersonic flow is studied with a nanoparticle-based planar laser scattering (NPLS) method. Based on the calibration, i.e., the density distribution of the supersonic flow around a wedge, the density field of a supersonic VG is measured. According to movement characteristics of coherent structure in VG’s flow fields and the basic concepts of wavelet, the density fluctuating signals and multi-resolution characteristics of density field images are studied. The multi-resolution characteristics of density fluctuation can be analyzed with wavelet transformation of NPLS images. The wavelet approximate coefficients of density fluctuating signals exhibit their characteristics at different scales, and the corresponding detail coefficients show the difference of diverse layer smooth approximation in some way. Based on 2D wavelet decomposition and reconstruction of density field images, the approximate and detail signals at different scales are studied, and the coherent structures at different scales are extracted and analyzed.     

直纹面叶轮刀具轨迹规划的研究(英文)

At present, most commercial computer-aided manufacturing （CAM） systems are deficient in efficiency and performances on generating tool path during machining impellers. To solve the problem, this article develops a special software to plan cutting path for ruled surface impellers. An approximation algorithm to generate cutting path for machining integral ruled surface impellers is proposed. By fitting sampling data points of an impeller blade into a curve, a model of ruled surface blade of an impeller is built up. Furthermore, by calculating the points where the cutter axis vector intersects the free-form hub surface of an impeller, problems about, for instance, the ambiguity in calculation and machining the wide blade surface with a short flute cutter are solved. Finally, an integral impeller cutting path is planned by way of an integrated cutter location control algorithm. Simulation and machining tests with an impeller are performed on a 5-axis computer numerically controlled （CNC） mill machine, which shows the feasibility of the proposed algorithm.