输气管道天然气连续取样器的研制及应用

文章针对国内管输天然气气质分析工作中取样环节所存在的问题，结合国外技术发展趋势，全面地介绍了输气管道天然气连续取样器的研制过程。实践证明，该装置较好地解决了天然气密度值偏差问题，满足管输天然气全分析的要求，同时，该装置的推广应用将会提高天然气的计量准确度。     

Chemical mechanical polishing of polymer films

Strategies to reduce capacitance effects associated with shrinking integrated circuit (IC) design rules include incorporating low resistivity metals and insulators with low dielectric values, or “low-κ” materials. Using such materials in current IC fabrication schemes necessitates the development of reliable chemical mechanical polishing (CMP) processes and process consumables tailored for them. Here we present results of CMP experiments performed on FLARE™ 2.0 using a specialized zirconium oxide (ZrO₂) polishing slurry. FLARE™ 2.0 is a poly(arylene) ether from AlliedSignal, Inc. with a nominal dielectric constant of 2.8. In addition, we provide insight into possible removal mechanisms during the CMP of organic polymers by examining the performance of numerous abrasive slurries. Although specific to a limited number of polymers, the authors suggest that the information presented in this paper is relevant to the CMP performance of many polymer dielectric materials.     

Digital Connectivity and Extended Well-Composed Sets for Gray Images

In this paper, we propose a new definition of digital connectivity for gray images on a 2D space for arbitrary grid systems. We extend a digital version of the Jordan curve theorem and its converse proved earlier by Rosenfeld for the rectangular grid system. We also extend in two directions the concept of well-composed sets introduced by Lateckiet al.(1995,Comput. Vision Image Understanding61,70–83). First, we extend the definition of well-composed sets from the quadratic grid system to an arbitrary grid system. Then, by using the concept of parameter-dependent connected components introduced by us in a previous work, we allow the pixels in a connected component of a well-composed set to have different gray values so that the connectivity of connected components accommodates a wider meaning.     

LZW压缩算法解析及应用设计

ＬＺＷ压缩算法是一种无限压缩算法，它主要是用一种代码来表示数据流中出现的重复串，以达到压缩的目的。     

北淮阳金寨-霍山地区火山机构遥感地质解译研究

利用不同时期成像的航卫片资料，圈定和寻找北淮阳金寨－霍山地区火山机构，结合地面验证，研究火山活动的空间展布规律，以及火山机构的成矿控矿作用。     

PXJ—Ⅱ排险机器人

介绍了一种可在危险环境下作业的遥控机器人－－ＰＸＪ－Ⅱ排险机器人，分析了其功能指标及结构，简述了以武器系统和传感器为主的机器人辅助系统及其实用意义。     

Isolation of a genetic locus associated with metronidazole resistance in Helicobacter pylori

We examined the molecular mechanism of metronidazole resistance by constructing a lambda-Zap II phagemid expression library with genomic DNA from a metronidazole-resistance strain of Helicobacter pylori. Twenty-two clones were found to have elevated MTZ resistances in XLOLR strain of E. coli. Phagemids belonging to the twenty two clones were extracted and then retransformed into the XLOLR strain of E. coli. After MTZ selection, five clones could confer metronidazole resistance consistently. According to Southern hybridization and DNA sequencing, the five clones contained a same locus, recA. In addition, transforming the five clones into BL21 strain of E. coli produced a higher resistance to MTZ. Interestingly, electroporation of one of the five phagemid clones into two MTZ sensitive H. pylori yielded MTZ resistant strains. Comparing amino acid sequence in MTZ resistant with sensitive isolates revealed two point mutations at this locus. Above results suggest that mutation in recA may be associated with metronidazole resistance of H. pylori.     

以CGA卡为基础的智能显示系统

本文介绍了以微处理器与ＩＢＭ－ＰＣ上的彩色／图形适配器相结合构成的一种智能显示系统。本系统主要解决数控系统中主ＣＰＵ与６８４５ＣＲＴＣ争夺显示缓存的矛盾。保证了６８４５ＣＲＴＣ对显示缓存操作的时间要求；并且保证了数控系统中主ＣＰＵ对显示缓存操作的随意性。     

高速钢W6Mo5Cr4V2的脱磷试验

在３０ｋｇ感应炉上用ＣａＯ－Ｎａ２ＣＯ３－ＣａＦ２－ＦｅｘＯ（ＭｏＯ３）渣、ＭｏＣｌ６粉剂和Ａｌ－Ｃａ合金作脱磷剂对高速钢Ｗ６Ｍｏ５Ｃｒ４Ｖ２进行脱磷试验。结果表明，ＣａＯ－Ｎａ２ＣＯ３－ＣａＦ２－ＦｅｘＯ渣的脱磷效果最好，一般脱磷率可达２６％￣５６％。     

Optimal solutions for a dynamic bandwidth allocation scheme in high-speed networks

In this paper, we investigate the problem of determining the optimal bandwidth allocation for a Dynamic Bandwidth Allocation Scheme (DBAS). The objective is to minimize the total amount of bandwidth required to satisfy the Quality of Service (QoS) requirements of all traffic streams. It is shown that when the performance functions satisfy a certain number of conditions, there exists a unique optimal bandwidth allocation such that, for each traffic stream, either its QoS is just satisfied or its QoS is over-satisfied and it is allocated zero bandwidth. Such an allocation is said to be efficient. It is also shown that there exists a unique efficient allocation in the entire feasible region. An iterative algorithm is developed to compute the efficient allocation employing its special properties. Numerical examples are presented to demonstrate how the algorithm works. Future extensions of this work are also discussed.Partially supported by NSERC of Canada through grants OGP14020 and STRIN-200.