Walk－off型光隔离器的隔离度和插入损耗分析

本文介绍了与偏振无关的ｗａｌｋ－ｏｆｆ型光隔离器的原理和结构，从理论和实验两方面分析了影响隔离度和插入损耗的因素，定量计算了加工、调整误差、消光比等对隔离度和插损的限制，给光隔离器的选材、加工和调整提供了依据。     

A note of ins-primitive words

The aim of this article is to investigate the properties of primitive words with respect to insertion operation, called ins-primitive words. This includes the investigation of properties concerning primitive words (with respect to catenation operation) in order to show our result concerning the self-insertion of a word. We also show that the set of all ins-primitive words is not only dense but also disjunctive (hence not regular).     

A generalized constructive algorithm using insertion-based heuristics

In this paper, a generalized constructive algorithm referred to as GCA is presented which makes it possible to select a wide variety of heuristics just by the selection of its arguments values. A general framework for generating permutations of integers is presented. This framework, referred to as PERMGEN, forms a link between the numbering of permutations and steps in the insertion-based heuristics. A number of arguments controlling the operation of GCA are identified. Features and benefits of the generalized algorithm are presented through the extension of the NEH heuristic, a successful heuristic solution approach of Nawaz, Enscore, and Ham for the permutation flowshop problem (PFSP). The goal of the experimental study is to improve the performance of the NEH heuristic on the PFSP. To achieve this goal, the space of algorithmic control arguments is searched for a combination of values that define an algorithm providing lower makespan solutions than NEH, in a linear increase of CPU time. Computational experiments on a set of 120 benchmark problem instances, originally proposed by Taillard, are performed to establish a more robust version of the original NEH constructive heuristic. The proposed procedures outperform NEH, preserving its efficiency and simplicity.     

光纤到户工程用户光缆的验收测试

依据国家标准和IEC标准中关于光纤到户工程用户光缆的设计和施工验收相关规定,介绍住宅建设方负责施工的用户光缆部分的验收测试指标的要求、测试方法的选择以及测试仪表的使用,包括用户接入点与工程界面的划分;用户光缆光链路的构成和传输指标;采用光源光功率计测试光纤链路衰减指标的方法等。     

插入式涡街流量计比对方法探讨

简单介绍了插入式涡街流量计的构成及点流速计型的插入式涡街流量计的标定方法。简要分析了用水泵流量比对,便携式超流量计比对方法的缺点,提出了插入式涡街流量计的标定修正比对的快速查表法,实例证明该方法是有效可行的。     

从CITME‘98看国产剑杆织机的技术进步

简述了剑杆织机的发展过程。将第六届中国国际纺织机械展览会（ＣＩＴＭＥ’９８）上国产剑杆织机的引纬机构归纳为四个类别，分述其性能并与同类进口织机对比，表明其技术进步程度。     

一个改进的循环2路插入排序算法

对一个循环2路插入算法进行了改进,其有序区在序列的始末连接端形成,简化了算法实现,算例表明排序效率也得到了一定提高.     

设计施工中常见几例问题的分析

根据不同石油化工装置施工安装过程中出现的问题,继本刊2006年第4期发表的“设计、供货及施工中常见问题的分析”之后,再次总结了几种在工程设计、施工中常出现的错误,分析了错误出现的原因和带来的后果,并就预防措施提出了建议。     

pH sensing in aqueous solutions using a MnO2 thin film electrodeposited on a glassy carbon electrode

An electrolysis technique at a constant potential was used to develop a highly reproducible and fast elaboration method of adherent manganese dioxide thin films on a glassy carbon electrode from aqueous solutions containing sulfuric acid and manganese sulfate. The resulting films were found to have a nanostructured character presumably due rather to birnessite (δ-MnO₂) than to γ-MnO₂, as suggested by their Raman and XRD signatures. They lead to modified electrodes that present an obvious although complex pH dependent potentiometric response. This sensor indeed showed a single slope non-Nernstian linear behaviour over the 1.5–12 pH range for increasing pH direction (“trace”), whereas a Nernstian two slopes linear behaviour was observed for decreasing pH direction (“re-trace”). Preliminary EIS experiments carried out at a pH value of 1.8 seem to reveal a sensitivity mechanism based on proton insertion process at least at highly acidic pH values.