柔性软管敷设过程及安装计算分析

柔性软管有水平敷设方式和垂直敷设方式,2种敷设方式均可划分为4个敷设过程。介绍软管具体敷设过程及特点,论述软管安装计算分析理论。针对工程项目实例,依据软管敷设过程,进行柔性软管安装计算分析,确定软管敷设工作所需关键参数。研究工作可对柔性软管在海洋石油工程上的应用提供参考。     

有载分接开关气体继电器频繁动作的对策

介绍了国产有载分接开关气体继电器状况,分析了气体继电器频繁动作的原因.     

EPR and Raman study of silicon layers obtained by gas detonation spraying

We demonstrate availability of gas detonation deposition spraying (GDS) to obtain silicon layers that can be used for production of solar cells. Silicon powder remaining as secondary raw material of silicon and/or silicon production is used during GDS. To study defects and structural perfection of initial powders and obtained layers, electron paramagnetic resonance (EPR) and Raman spectroscopy are used. It is shown that one part of EPR spectra displays resonances originating from different nearest-neighbor configurations of silicon dangling bonds, whereas an increase of the total number of paramagnetic defects in GDS silicon layer is related to the rise of conduction electrons or electrons filled band tail states. Thermal annealing of layers in hydrogen ambience further reduces the number of silicon dangling bonds owing to their passivation. Based on the results of X-ray diffraction, EPR and Raman spectroscopy it is assumed that the GDS Si layers are composed of randomly oriented and partially oxidized monocrystalline silicon grains. It is found that optical and photoelectric properties of the layers obtained indicate a possibility to apply them for solar cells production.     

Interfacial modifying layer-driven high-performance organic thin-film transistors and their nitrogen dioxide gas sensors

Organic thin-film transistors (OTFTs) based on bottom-gate bottom-contact configuration were fabricated by inserting two kinds of modifying layers at the interface of source/drain electrode and organic semiconductor, while nitrogen dioxide (NO₂) sensing capability was also evaluated based on the obtained OTFTs. Compared to OTFT without interfacial layer, the field-effect mobility (μ) was enhanced from 0.018 cm²/Vs to 0.15 cm²/Vs by incorporating with MoO_x interfacial layer. Moreover, when exposed to 30 ppm NO₂, the saturation current and μ of OTFT with MoO_x interfacial layer increase 22.7% and 26.7%, respectively, while in original OTFT, the values are only 3.0% and 3.7%, respectively. The mechanism of performance improvement of OTFT sensor was systematically studied by focusing on the interface of source/drain electrode and organic semiconductor. The reduced contact resistance leads to higher μ, meanwhile, pentacene morphology modulation on MoO_x contributes to better diffusion of NO₂ molecules. As a result, higher μ and more diffused gas molecules enhance the gas sensing property of the transistor.     

管道生产信息网络拓扑分析及改进

随着数字管道的建设和发展,信息网络是实现生产管理智能化、事务处理自动化、数据共享远程化不可或缺的纽带和基础设施。针对某管道储运企业的网络建设情况,通过网络拓扑结构可靠性分析,从连通性和结合度的角度,对网络可靠性进行探讨,查找影响网络可靠运行的链路连通问题。在综合考虑投资与效益等因素,提出了基于原有拓扑结构,适当增加链路冗余,配置路由策略等改进措施,停机断网次数减少,有效地控制网络碎片产生,取得了明显的效果。     

高精度正余弦函数的FPGA实现

在研究CORDIC算法的数学基础上,采用流水线的硬件结构实现了该算法,并在Ahera公司的FPGA芯片上进行了验证,使正余弦函数的计算达到了实时性、高精度的要求.该设计模块完全支持超过360°的大角度数据输入,多数数据精度达到了10-9,时钟频率可以达到233.2 MHz.测试结果表明,该系统具有较高的精确度和稳定性.     

基于网络处理器的VLAN的研究与实现

考虑到传统交换芯片将VLAN(虚拟局域网)数据包解析固化于硬件之中,无法更改处理流程等因素,文章提出了一种基于网络处理器可编程流水线解析VLAN数据包的方案.对可编程流水线的处理机制进行了研究,分析了VLAN的映射原理,并详细描述了VLAN模块的实现过程.测试结果表明,该软件能稳定运行,对下一步QinQ(VLAN嵌套)...     

移动互联网时代流量经营策略探析

移动互联网时代,国内电信运营商正面临被管道化的风险。如何在用户高普及背景下扭转收入、客户双份额缓增局面,是运营商亟待解决的问题之一。本文从消费者信息需求转变出发,以经营数据分析为基础,阐释流量经营的必要性。并结合国外运营商的先进经验,立足操作层面,提出了流量经营的策略建议。     

基于FPGA的32位MIPS-CPU平台开发

文章参考opencores组织的开源代码,完成基于5级流水线的32位MIPSCPU的设计,并通过增加相关逻辑解决流水线冒险与竞争。设计的CPU文中称为OPS1-CPU,使用基于Windows-DOS系统搭建gccmips_elf编译系统,用来对应用程序进行编译、链接与执行,生成相应汇编语言程序以及仿真向量文件。最终将设计的OPS1-CPU成功下载到ALTERA公司的FPGA芯片EP1C6Q240,进行了板级的指令级调试与验证,证明OPS1-CPU硬件系统与编译系统运行正常,完成MIPS系统的平台搭建。     

通信电缆管道和其他地下管线的交越

本文介绍了通信电缆管线与其他专业地下管线交越的一般原则和具体情况应对措施.