广州地铁集中冷站的自动控制

本文介绍广州地铁二号线集中冷站的空调制冷自动控制系统的设计，对其控制原理与节能优化进行分析。     

高功率双工旋转场移相器

旋转场移相器具有移相精度高(均方根误差可小于1°)和温度稳定性好等特点,通过改进射频传输结构,可大大提高他的功率容量。利用旋转场移相器的互易特性和铁氧体圆极化器的非互易特性,设计出高功率双工旋转场移相器。其双工特性可将收/发信号分开,实现移相器和环行器的双重功能,用于天线的收发通道等场合时,可省去一个高功率环行器,结构紧凑。分析了双工旋转场移相器的工作原理,阐述了高功率应用下的设计方法,推导出了管状铁氧体的相移量计算公式,按此方法设计了实用的器件,并给出了试验数据。     

我国有线电视的网络媒体价值

阐述有线电视网络媒体的特点，有线电视网络媒体面临的困境及解决办法，最后展望有线电视网络媒体价值。     

DFB active filter/detector for multichannel FSK optical transmission

In a DFB laser amplifier, used simultaneously as narrow band optical filter and detector in O-FDM systems the increase of the input optical power induces distortion of the filter transfer function. The effect of such a distortion on the receiver sensitivity and dynamic range has been investigated in a 155 Mbit/s FSK direct detection experiment. A two-channel experiment is also reported for the first time. Owing to the effect of interference between the two channels, it has been found that a minimum channel spacing of about 15 GHz is required to maintain the bit error rate below 10/sup -9/.<>     

非均相成核中间相炭微球的形成过程及其结构演变

以含有喹啉不溶物的煤焦油沥青为原料，在410℃、不同反应时间下获得一系列中间相炭微球(MCMB)和小于0．5μm的碳质颗粒(SCP)。通过对中间相沥青的软化点、族组成和MCMB、SCP的形貌及MCMB断面结构的分析，认为非均相成核MCMB的形成和生长过程不同于均相成核的融并生长过程，而是SCP碳质颗粒的构筑过程，我们称之为“球形基本单元构筑”过程。在MCMB生长过程中，体系的黏度对SCP的形成和MCMB的生长起着重要的作用。非均相成核MCMB的内部结构不是三种模型结构(“地球仪”型、“洋葱”型和“同心圆”型)中的任一种，而是炭层具有收缩点的复杂结构，并且球体的结构不具有“继承性”，即随着反应时间的延长而不断发生变化和调整。MCMB内部分子在球体生长过程中的主要变化趋势是分子的不断缩合长大，而不是分子片层的平行趋向。     

自动控制原理考试系统的设计与实现

对基于Visual Basic 6．0开发的自动控制原理考试系统的系统结构做了阐述，并简要介绍了该系统的设计思想、主要功能及实现方法。     

煤矿污染防治技术群及其评价

通过对枣庄矿区污染防治工作的调查研究，分析了煤矿开采对环境的影响，总结出当前煤矿污染防治的适用技术群，井对其相关问题进行评价。     

Impact of Aspen Log Storage with and without Protection on OSB Performance

Outdoor log storage without protection can change the mechanical and chemical properties of wood due to infection by various fungi. To understand how outdoor log storage affects the wood and, subsequently, the strandboard quality, two piles of aspen logs were set up outside and stored for a period of four months (July to November). One of the piles was treated with a biological solution to prevent fungal growth. The other one was stored without treatment. Both piles contained non-debarked and partially debarked logs. Evaluation of sap stain development indicated that all logs had been colonized by staining fungi with average stain coverage of 9.37 to 57.18% and maximum stain penetration of 3.58 to 7.27 cm over the log cross section. The variation of fungal colonization depended on log treatment and bark condition. The most effective way to prevent stain growth was the combination of biological treatment and partial debarking. A series of strandboard was prepared from fresh and aged aspen logs. All boards made from stored logs were statistically comparable to or superior to the control boards made from fresh aspen logs. The boards made from treated/partially debarked and untreated/non-debarked logs were statistically comparable to each other except for wet MOR. In addition, these two board types were statistically stronger than other boards made from treated/non-debarked and untreated/partially debarked logs in terms of IB and water resistance. Some individual stained strands were observed on the finished board surface. Less staining was found in the boards prepared from biologically treated and partially debarked logs, compared with those made from other stored logs.     

临床检验实验室自动化与实验室国际标准化认可的准备

临床检验实验室的自动化集中管理（LAS）及实验室的认可是目前临检专业讨论比较集中的问题.与传统的实验室比较分散、各自独立的分析设备相比,LAS具有集成度高,能够充分利用检验设备资源,与临床信息系统（CIS）联系更密切的特点.本文就实际临床检验中心投入的实验室集中管理系统,对其结构、流程设计、以及导入自动化系统前后实验室改造所带来的变化进行了分析.