一种基于虚拟页地址映射的NAND Flash管理算法

本文提出了一种基于虚拟页地址映射的NAND Flash管理算法.该算法通过定义坏块表、对应表等结构，以及设计的坏块替换策略和虚拟页地址到实际物理页地址的转换算法，实现上层软件采用虚拟地址对NAND Flash的无坏块连续页地址访问.该算法是一种高效的地址映射算法，能高效地对数据进行索引，占用SRAM空间较少，使系统达到高性能，并使得闪存使用的更加稳定持久.     

IL-E2线阵遥感相机的研制和TDI分析

针对低照度、高速物体测量等应用场合,介绍了一款高灵敏度的线阵相机的研制方案,相机的线阵CCD芯片采用DALSA公司的IL-E2 ,它具有96级TDI功能,灵敏度比一般的线阵CCD相机提高了约20倍,大幅度提高了相机的整体响应水平,通过试验,得出结论,TDI性能的良好发挥必需依靠图像与TDI数据流精确的同步,即使10%的失步也会造成相机灵敏度的严重退化,因此在精确控制像速度的情况下,更适合作为一款遥感相机来使用.     

对高频电路原理图绘制问题的探讨

本文结合Protel 99 SE在高频PCB设计中的应用,着重探讨在电路原理图的绘制上需要重点注意的一些特殊问题,并提出解决问题的方法,尽可能地减小对高频PCB设计的影响,提高PCB设计的效率。     

Water Cherenkov detectors:MILAGRO

This paper discusses the properties of using the water Cherenkov technique to detect air showers in the few hundred GeV to 100 TeV energy range. The responses of a 6 m² 2 m deep water Cherenkov counter and that of a 6 m² 10cm thick scintillator-lead sandwich counter to air shower electrons and photons is described. The advantages of water Cherenkov detector is outlined. Its application to do VHE gamma ray astronomy is discussed with particular reference to the MILAGRO telescope currently under construction. Milagro, a water-Cherenkov detector to do gamma ray astronomy above 100 Gev, uses an existing pool 60m × 80m by 8m, located in the Jemez mountains near Los Alamos, NM. The threshold of the MILAGRO detector is comparable to atmospheric Cherenkov detectors, however it has several advantages over these optical detectors. MILAGRO can operate 24 hours a day in all weather conditions and it has an open aperture which allows it to view the entire northern sky every day. These capabilities allow for a systematic all-sky survey to be done for the first time at these energies. MILAGRO will measure the Crab spectrum with high significance over a wide energy range, it will detect and measure the spectra from AGN's such as MRK 421 and it will search for short duration bursts from GRBs and possibly evaporating PBHs.     

高精度算术运算

本文针对当前各种计算机高级语言运算精度的不足，用PASCAL语言实现了高精度的加、减、乘、除算术四则运算。以满足教学、科研的实际需要。     

Modelling of Spall in an Anisotropic Aluminium Alloy

Spall caused by hypervelocity impacts at the lower range of velocities could result in significant damage to spacecraft. A number of polycrystalline alloys, used in spacecraft manufacturing, exhibit a pronounced anisotropy in their mechanical properties. The aluminium alloy AA 7010, whose orthotropy is a consequence of the meso-scale phase distribution or grain morphology, has been chosen for this investigation. The material failure observed in plate impact was simulated using a number of spall models. The Hugoniot elastic limit and spall strength have been studied as a function of orientation, and compared to experimental results.     

故障检测与分离的广义一致性算子法

本文提出了故障检测与分离的广义一致性算子法的一般形式。得出了两个故障可分离的充要条件和多个故障可分离的充要条件。最后给出了检测和分离故障的过程。     

低轨道带可变翼的平板型极高真空分子屏

本文计算了在低轨道自由飞行的平板型分子屏（ＷａｋｅＳｈｉｅｌｄＦａｃｉｌｉｔｙ）加了可变翼后，分子屏后实验区的压力分布。计算中考虑了分子屏和翼材料出气对实验区压力的影响。本文并对加可变翼和不加可变翼、考虑出气和不考虑出气几种情形进行了计算和比较。我们的结果表明：给轨道分子屏加上可变翼后，其实验区的压力可比不加可变翼降低一个数量级以上，压力达１０－１３Ｐａ。本文的研究表明，这种给轨道分子屏加可变翼的模型对更好的利用分子屏环境是非常有利的。     

炭/炭复合材料防氧化涂层研究进展

介绍了近两年国内外开发的几种C/C复合材料高性能抗氧化涂层的微观结构和高温氧化行为,表明SiC-Al2O3-莫来石、SiC晶须增韧陶瓷、硅酸钇等涂层1500℃静态空气环境下均具有长时间防氧化能力,部分涂层还具有优良的抗热震性能。其中采用原位形成法制备的硅酸钇涂层具有极佳的抗氧化性能,可在1600℃空气中对C/C复合材料有效保护200 h。此外,还介绍了部分涂层的失效机理,并就C/C复合材料抗氧化涂层下一步研究重点提出一些见解。     

八作动器隔振平台的通道耦合分析及解耦控制

分析一种对称结构的八作动器隔振平台的通道耦合特性。分析表明由于结构对称，当有效载荷质心位于平台纵轴的延长线上，且有效载荷的惯性主轴与平台对称轴平行时，平台可分解成两个独立的单自由度系统和两个2阶耦合子系统。利用矩阵同时对角化方法对平台的2阶耦合子系统进一步解耦，仿真结果显示解耦控制能够衰减被动隔振的谐振峰，改进平台的隔振性能。