单模光纤最小群速度色散波长附近的调制不稳定性

利用修正的非线性Ｓｃｈｒｏｄｉｎｇｅｒ方程研究了单模光纤最小群速度色散波长附近的调制不稳定性，发现了一个新的由光纤四色散导致的调制不稳定性区域，该区域的调制范围与初始入射脉冲的功率和四阶色散有关。     

动态波前相位的高分辨率测量

动态波前相位信息测量是大气光学，气动光学和激光技术等领域的重要实验手段。提出了一种具有高的时间和空间分辨率以及长的测量持续时间的动态波前相位测量方法。应用Ｈａｒｔｍａｎｎ－Ｓｈａｃｋ波前传感器获得高空间分辨率的相位信息，采用高帧频ＣＣＤ摄象机获得高时间分辨率图象数据。     

Information systems effectiveness: research designs for causal inference

Abstract. This paper examines the capacity of the research designs of 37 empirical studies of information systems (IS) effectiveness to provide a basis for the development of theories about behaviour related to IS effectiveness. The power of each study to support causal inference was evaluated in terms of (a) its handling of the time dimension, (b) its ability to weigh differences and (c) its resistance to internal validity threats that pose alternative explanations for its reported findings. Of the reviewed studies, 29.7% could account for the time dimension, 32.4% employed a comparison group and 16.2% were not susceptible to any internal validity threats. Only 13.5% of the studies combined an accounting for the time dimension with the use of a comparison group. Of these, however, only 5.4% were also invulnerable to internal validity threats. The research designs of nearly 95% of these published studies were deficient in supporting causal inference. In those studies, suggestions that one variable was causally related to another variable could not be substantiated. Encouragement for the future capacity of IS effectiveness research to support causal inference was found in a trend towards the use of quasiexperimental designs. Recommendations are made regarding ways to increase the inferential capacity of research designs employed in the study of IS effectiveness.     

An exploration of the problems of using function points mark II

Abstract. This paper examines critically the function point analysis mark II (FPA mark II) method of measuring the functionality of information systems. Although the focus of the paper is on FPA mark II as devised by Symons, both this and the Albrecht method, from which the FPA mark II was developed, are briefly discussed. The published attempts to validate FPA mark II are reviewed and then the problems encountered by the author in applying the approach are described. The final part of the paper is concerned with the fit between SSADM and FPA mark II.     

硼酸铝钕(NAB)晶体光学均匀性的测量

NAB晶体是一种综合性能较好的新型激光工作物质,有希望做成高效的小型固体激光器。本文介绍一种测量这种晶体光学均匀性的方法。 一般都采用在干涉仪上观测干涉图样来判定激光棒的光学均匀性。NAB晶体的吸收光谱曲线显示出其在可见光光谱区内有多个吸收峰。我们注意到:通常用做激光干涉仪光源的He-Ne激光器发射的632.8nm谱线正位于NAB晶体的一个吸收峰,并用输出约为45mW     

光孤子相互作用对压缩态的影响

在线性近似条件下，量子化了非线性薛定谔方程，用后向传播法数值求解了光孤子相互作用对压缩比的影响。数值结果表明，在碰撞距离附近，压缩比显著增加。     

海上靶场角度量录取系统的研制

本文详细叙述了海上靶场角度量录取糸统的组成、测试原理及其功能设计，简要介绍了该系统在靶扬的应用情况．     

一种双光束自动测试光栅绝对与相对光谱衍射效率的原理性方案

提出了一种快速自动测试光栅光谱衍射效率的新方法。重点推导了测试平面光栅绝对光谱衍射效率与相对光谱衍射效率公式，介绍了双光束高精度自动测试光栅光谱衍射效率曲线的基本原理、方案与方法，并分析了测试精度。研究表明，本方案的测试速度和精度均比一般测试方法提高一倍，并能有效地消除光源波动对测量结果的影响，测量误差小于５×１０－３。     

Si_（1－x）Ge_x／Si定向耦合器的研制

在运用ＳｉＧｅ脊形波导单模条件和有效折射率法分析ＳｉＧｅ／Ｓｉ定向耦合器结构参数的基础上，采用分子束外延和各向异性腐蚀技术制备出Ｓｉ１－ｘＧｅｘ／Ｓｉ（ｘ＝０．０５）单模定向耦合器．在波长为１．３μｍ时，平均串音小于－１８．１ｄＢ，输出功率耦合效率达到９８．１％