激光驱动内爆低产额中子探测

采用新研制的BF_3计数管阵列测量激光驱动(包括间接驱动和混合驱动)充DT玻璃微球靶内爆中子产额。着重介绍BF_3计数管阵列的设计及特点,高压门电路的研制和1990年在上海“神光”装置上的测量结果。     

混合集成微型光纤光谱仪的实验测定

文中简述了所研制微型光谱仪的基本原理和基本结构,并对该微型光谱仪进行了实验测试和标定。在实验中采用汞灯作为测试所用的光源,分别使用不同芯径和数值孔径的光纤作为光输入元件,实验结果表明该光谱仪具有很好的线性度,在采用50μm的多模光纤时,光谱分辨率可达13.8nm,在采用9μm的单模光纤时分辨率可以达到5.5nm。     

用角锥棱镜阵列抑制低频波前畸变

 分析了角锥棱镜阵列“准”位相共轭特性的原理；采用模拟计算的方法，验证了角锥棱镜阵列对低频波前畸变的抑制作用，并研究了其单元数的优化，指出了该方法的局限性和有效应用范围。研究结果表明，采用该方法能有效地提高畸变激光束的焦斑能量集中度，对于抑制双程同轴激光系统的大幅动态低频波前畸变具有现实的应用意义。     

Design and results for a 345 GHz sis focal plane array using planar technology

We describe a focal plane array using antenna elements and SIS junctions photo-etched on a quartz substrate. The etched antenna is of a new strip-line type in which a two-dimensional corrugated horn is phase-corrected with a strip-line lens. Good beam efficiency is indicated by the measured antenna patterns. A DSB receiver temperature of 225 K was obtained with a number of imperfections still present.     

Cellular processing for edge detection in an optical shadow casted architecture

The principles of two-dimensional cellular processing are utilized to obtain the edges of a binary image in an optical shadow casted architecture. The processing steps, based on image logic algebra are introduced where operation kernels are set by the on/off states of four light sources. The input binary image is shifted, superimposed, then logically operated and finally decoded to obtain the edges. The whole process is controlled by a microcomputer. Experimentally simulated results are presented.     

New text indexing functionalities of the compressed suffix arrays

New text indexing functionalities of the compressed suffix arrays are proposed. The compressed suffix array proposed by Grossi and Vitter is a space-efficient data structure for text indexing. It occupies only O(n) bits for a text of length n; however it also uses the text itself that occupies bits for the alphabet . In this paper we modify the data structure so that pattern matching can be done without any access to the text. In addition to the original functions of the compressed suffix array, we add new operations search, decompress and inverse to the compressed suffix arrays. We show that the new index can find occ occurrences of any substring P of the text in O(|P|logn+occlog^εn) time for any fixed 1ε>0 without access to the text. The index also can decompress a part of the text of length m in O(m+log^εn) time. For a text of length n on an alphabet such that , our new index occupies only bits where is the order-0 entropy of the text. Especially for ε=1 the size is bits. Therefore the index will be smaller than the text, which means we can perform fast queries from compressed texts.     

The Existence of a Symmetric Transversal Design STD 7[21; 3]

In this note we construct a symmetric transversal design STD₇[21; 3]. Therefore there exists an orthogonal array OA(63, 21, 3, 2). Communicated by: J.D. Key     

自聚焦透镜列阵重叠度的研究

本文讨论了自聚焦透镜列阵重叠度,分析了重叠度对分辨率及照度分布的影响,并对一系列单根自聚焦透镜和两列自聚焦透镜列阵作了测量,得到了制造自聚焦透镜列阵的一个重要依据.实验中总结出照度分布不均匀规律的经验公式.     

寻找超高能宇宙线源——西藏广延空气簇射实验

总结了１９９０年６月到１９９３年１０月期间西藏空气簇射阵列的观测结果。寻找了来自于蟹状星云、Ｘ射线双星、脉冲星、活动星系核和其它活动天体的能量为１０ＴｅＶγ射线连续发射，没有发现连续稳定发射的迹象，但给出了每个源的流强上限。在阵列所观测的天区寻找了１０ＴｅＶ的γ暴，结果没有发现能量１０ＴｅＶ的γ暴，最后也给出了发现此种γ暴的上限。应用该阵列，明显地观测到了能量为１０ＴｅＶ的宇宙线流强的太阳和月亮阴影。观测了朝向和远离太阳的行星际空间磁场对宇宙线阴影的影响，这是行星际磁场对阴影位移影响的第一次直接观测。研究并发现在实验期间，太阳阴影的位置每年都在变化。同时观测在此期间，朝向和远离方向的宇宙线阴影的不同变化。另外，应用该实验的数据，给出了所谓的“膝”区的原初宇宙线能谱。     

混合式红外焦平面阵列的进展

着重介绍锑化 (InSb)、碲镉汞(HgCdTe)、硅化铂(PtSi)等混合式红外焦平面阵列(HIRFPA)的现状和发展前景。