三阶变形的非线性传输方程及其孤子解

本文用简单数学方法直接导出了有耗单模光纤的三阶变形的非线性传输方程及其解析的孤子解。     

A simple method for calculating the reflection coefficient ofopen-ended waveguides

This paper presents a simple but effective method for the analysis of open-ended waveguides. The method begins with the introduction of a large waveguide to approximate the half-space. In order to avoid the convergence problem lossy dielectric is assumed to homogeneously fill the large waveguide. After obtaining a number of convergent data for different values of the loss tangent an extrapolation technique is employed to calculate the solution to the original problem-a waveguide terminated by an infinite conducting range and radiating into a lossless or low-loss half-space. Numerical results are given to show the validity of the proposed method. The behavior of the effect of the loss tangent on the size of the large waveguide and on the final results are also examined     

高效Nd:S-VAP激光器的特性研究

报道了激光二极管泵浦高效ＮｄＳ－ＶＡＰ激光器输出特性的研究结果。激光晶体掺钕浓度为～３％，厚度为２．６ｍｍ，基横模输出功率为２３３．０ｍＷ，斜率效率为４２．２％     

天然气转化利用技术的研究进展

主要评述了自1995年以来,全球天然气转化利用商业化技术的重大进展,包括合成气生产、天然气制合成油、含氧化合物生产(主要是甲醇和二甲醚)、甲醇制烯烃。综述了甲烷脱氢芳构化反应制苯、部分氧化制甲醇、氧化偶联制乙烯的研究进展,并对发展我国天然气化工提出建议。     

酮苯装置用加氢裂化尾油生产优质白油料

加氢裂化尾油经溶剂脱蜡工艺生产出的高质量润滑油基础油,具有很好的低温流动性能,且对添加剂感受性好,硫、氮含量低,饱和烃含量高,可以调合中、高档润滑油,制备白油,综合利用加氢裂化尾油具有明显的经济效益。     

利用测井资料确定安全钻井液密度窗口

钻井液密度是保持井眼稳定的关键参数。本文从直井井壁应力分布和岩石破坏准则出发,系统地阐述了利用测井资料确定安全钻井液密度窗口的方法。根据该方法,利用某油田一口井的资料进行实例验证,结果表明,利用测井资料能准确地确定安全钻井液的上限和下限,为钻井工程提供了科学的数据依据。     

Watermarking scheme based on support vector machine for colour images

A novel watermarking scheme based on the support vector machine is proposed. The watermark is embedded in the blue channel of a colour image. By applying the embedded extra reference watermark, the support vector machine is trained, and then the watermark can be extracted by the trained support vector machine. Owing to the good generalisation ability of the support vector machine, even when the watermarked image is heavily distorted the watermark can be successfully extracted. Experimental results show good robustness of the proposed scheme.     

柱边边缘扫描检出模型的研究

本文建立了两种通用的柱边边缘扫描（白光扫描和激光扫描）检出的理论模型，给出了这两种模型的计算机仿真曲线，分析了影响边缘检出灵敏度的因素，并通过三种边缘检出方法验证了这两种模型的正确性。     

The Performances of the Antennas in Active/Passive Compounded Guidance Part II: Compounded Antennas Schemes and Performances of Active/Passive Guidance

The second part of a two-part paper discusses two kinds common-caliber compound antennas techniques for active/passive guiding system. One is the triple-antenna compound technique which two spiral antennas are utilized to find the direction of a radiative source in passive amplitude-phase monopulse subsystem and the other is used in pulse-radar. The next is the double-antenna technique which one antenna is for passive amplitude-monopulse direction-finding and the another is for pulse-radar. The mutual influence among these antennas is analysed in details and the better one in the scheme is pointed out finally in this paper.