THE THEORY OF SUPPORTING BROKEN ZONE IN SURROUNDING ROCK

The first topic discussed in this paper is to evaluate the present supporting theories,among which the typical two are collapse arch and elasto-plastic theories. The former is rather limited in practical application,and the latter is built up on some assumptions which is inconsis-tent with the reality,for it is of no need to support a roadway of which the surrounding rock is in elasto-plastic state. The second topic is to prove the objective existence of the broken zone in surrounding rock(BZSR) by a series of laboratory experiments and field measurements. The paper indicates that the object to be supported mainly is the bulking or expanding force resulted from the development of BZSR. This is remarkably different from the existing points of view which have been generally recognized nowadays. So far ,this theory has been tested in supporting more than ten thousand meters roadways located in various strata and has proved itself to have a great technoeconomical benefit.     

光纤骨干网络组网技术研究

随着近年来通讯技术的不断发展,原有的骨干网络组网方式已经不能够满足大量信息交换的需求,SDH组网技术也应运而生。     

试论我院“九五”教材建设的思路与对策

教材建设是高校教学三大基本建设之一，它不仅是衡量一所学校办学水平高低的重要标志之一，而且也是学校教学、科研实力的综合反映。我院在“九五”教育事业发展计划中，明确提出“九五”期间我院要完成出版教材和专著的宏伟计划。这充分说明了院领导对教材建设的重视，然而，要真正实现这一目标，必须制定合理、可行的“九五”教材建设规划和实施计划。我们不仅要看完成的数量，更注重完成的质量。     

光缆链路偏振模色散的统计模型分析

理论上分析比较了光缆链路PMD值的统计模型。介绍了常用的三种PMD统计模型：蒙特卡罗数值法（Monte Carlo Numeric Method）、Gamma分布分析法（Gamma Distribution Analytic Method）、模式独立分析法（Model-Independent Analytic Method）。指出统计模型的使用可以方便于从宏观上把握光缆娃路的PMD情况，一方面可以使生产厂家清楚生产出的光缆的PMD分市．为今后生产工艺的改进提供有效的PMD参数，决定改进的方向和需要注意的问题。另一方面可线为运营商在铺设新的光网络时，依照系统在PMD特性方面设计性能在光缆结构、型号、长度等方面的选用上有可靠的依据．或在系统扩容对对已有的光网络在PMD特性方面有准确的估计。 通过推导和数据分析讨论了Gamma分布分析法（Gamma Distribution Analytic Method）中系数K的取值，认为Gamma分布分析法在光纤偏振模色散统计模型中的使用还有待继续分析和讨论。 应用蒙特卡罗（Monte Carlo）数值法和模式独立（Model-Independent）分析法得出当前的G．652光缆链路的PMD分布，及链路PMD的平均值、标准偏差、设计值，最大传输距离。