一类多线性积分算子的端点有界性

本文对一类相关于非卷积型算子的多线性算子,证明了其在端点情形上的有界性,该算子包括Littlewood-Paley算子和Marcinkiewicz算子．     

基于半像素错位的多幅图像重建高分辨率图像技术研究

介绍了一种基于半像素错位的多幅图像重建高分辨率图像技术。分析了半像素错位的多幅图像与高分辨率图像各像素灰度值的对应关系 ,并从CCD数字化采样的角度进行了论证。同时 ,结合实际摄像机CCD结构 ,求出了高分辨率图像重建的计算公式 ,并通过实验进行了验证和完善。重建的本质是以原高分辨率图像的 4邻域平均图像为基础 ,增加一定比例的边缘细节信息 ,去接近原高分辨率图像。CCD的动态范围越大 ,图像的灰度级越多 ,那么计算误差就越小 ,图像的边缘细节信息就可以利用更多 ,重建的图像就越接近原高分辨率图像。通过实验和分析表明 ,利用半像素错位的多幅低分辨率图像重建高分辨率图像的原理是正确的 ,方案是可行的     

HeI photoelectron spectroscopic (PES) and quantum chemistry study on the dimeric compound of 2(5H) furanone

The He1 photoelectron (PE) spectra of both 2(5H) furanone and itstrans-chair-dimeric-compound (t-c-DFN) are reported. The assignment of the PES bands is made on the basis of band shapes, the PES results of the molecules which have the similar atomic groups, and the restricted Hartree-Fock (RHF) calculations for the molecules studied. From the results of both PES experimental and theoretical calculations, it is proved that the ionization potential (IPS) of the HOMO for the dimeric-compound is lower than that of the HOMO for the monomer. And the total energy computed for thet-c-DFN is the lowest in the four possible configurations of dimeric-compounds of 2(5H) furanone. Therefore the synthesis oft-c-DFN is also the easiest. Project supported by the National Natural Science Foundation of China.     

多约束下的串、并联混合系统可靠度与冗余度的优化判定模型及算法

本文给出了单目标多约束下串、并联混合系统中 ,由选取重要单元 (重要度最大的单元 )的方法 ,来提高系统可靠度的有效优化判定模型及算法 ,用同样思想给出了串、并联系统中冗余度的优化判定模型及算法     

Effects of Processing Parameters on Microstructure and Properties of Nanoscale ZrC/ZrB2 Multilayered Coatings

ZrC/ZrB2 multilayered coatings with bilayer periods of 3.5-40nm are synthesized by rf magnetron sputtering. Analyses of x-ray diffraction, scanning electron microscopy and nanoindentation indicate that multilayered coatings possess much higher hardness and greater fracture resistance than monolithic ZrC and ZrB2 coatings. A maximum hardness （41.TCPa） and a critical fracture load （73.7mN） are observed in the multilayer with A = 32 nm deposited at the substrate bias -40 V. Higher residual stress built in the ZrC layer can be released by periodic insertion of ZrB2 into the ZrC layer. A clear multilayered structure with mixed ZrB2（001）, ZrB2 （002） and ZrC （111） orientations should be responsible for the enhanced mechanical properties.     

The ordinary quiver of a weight three block of the symmetric group is bipartite

Suppose F is a field of characteristic p?5, and that B is a p-block of the symmetric group Sn of defect 3. We prove that the Ext¹-quiver of B is bipartite, with the bipartition being described in a simple way using the leg-lengths of p-hooks of partitions.     

广义Hénon映射的滑模变结构控制同步

基于可线性化的非线性离散变结构跟踪控制方法实现了广义Hénon映射混沌系统的同步.广义Hénon映射的混沌吸引子比Hénon映射的混沌吸引子要复杂得多,对于保密通信来说,这种复杂性正是所期望的.提出的同步方法允许参数有适当的失配程度,这对工程实现是非常有利的,理论分析和仿真结果证实了该方法的有效性 关键词： 广义Hénon映射 混沌 同步 变结构控制     

激光二极管侧面抽运Nd:YAG锁模激光器的研究

利用谐振腔的稳定条件对激光二极管侧面抽运的Nd：YAG锁模直腔的稳区特性和谐振腔内的光斑分布进行了分析。根据对腔参量的分析，选取合适的腔参量设计了一个简单的侧面抽运直腔，该谐振腔腔形简单，没有像散，振荡光模式好，有利于激光器的锁模运转。实验中采用国内自行研制的半导体可饱和吸收镜，实现了激光二极管侧面抽运半导体可饱和吸收镜锁模Nd：YAG激光器的连续锁模运转，平均输出功率为2W，锁模脉冲宽度为10ps，重复频率为100MHz。结合实验结果进一步讨论了半导体可饱和吸收镜的一些参量如饱和恢复时间、调制深度等对实现稳定连续锁模的影响。     

Triterpenoid Constituents of Huperzia miyoshiana

Thirteen triterpenoids, including three new ones, miyoshianois A (1), B (2) and C (3), were isolated from Huperzia miyoshiana. The structures of these new compounds were established as 3-O-dihydroferuloyltohogenol (1), 16-oxo-3β,21β-dihydrox-y-serrat-14-en-24-ferulate (2) and 16-oxo-3a, 21β-dihydroxy-serrat-14-en-24-ferulate (3), respectively, on the basis of their spectroscopic analysis.