Pulse propagation in superconducting coplanar striplines

The phenomenological loss equivalence method (PEM), the enhanced two-fluid model for thin-film superconducting materials, and the dynamical calculation of radiation losses in planar structures are used-in the context of a linear filter approach-to model attenuation and dispersion of ultrafast pulses in coplanar striplines. The numerical simulation of this modeling shows excellent agreement with experimental results available in the literature. Simple relationships between the peak attenuation and delay time of the propagation pulse, and penetration depth at absolute zero and conductivity at critical temperature may open the possibility of using pulse distortion to characterize thin-film, high-temperature superconducting materials     

稳频激光陀螺中闭锁阈值的变化

本文由腔反射镜反向散射标量理论与模耦合理论讨论激光陀螺在稳频时闭锁阈值、反向散射系数幅值及其位相与腔结构的关系,给出了相应的实验结果。     

Petroleum substitution, greenhouse gas emissions reduction and environmental benefits from the development of natural gas vehicles in China

This study develops a bottom-up model to quantitatively assess the comprehensive effects of replacing traditional petroleum-powered vehicles with natural gas vehicles (NGVs) in China based on an investigation of the direct energy consumption and critical air pollutant (CAP) emission intensity, life-cycle energy use and greenhouse gas (GHG) emission intensity of NGV fleets. The results indicate that, on average, there are no net energy savings from replacing a traditional fuel vehicle with an NGV. Interestingly, an NGV results in significant reductions in direct CAP and life-cycle GHG emissions compared to those of a traditional fuel vehicle, ranging from 61% to 76% and 12% to 29%, respectively. Due to the increasing use of natural gas as a vehicle fuel in China (i.e. approximately 28.2 billion cubic metres of natural gas in 2015), the total petroleum substituted with natural gas was approximately 23.8 million tonnes (Mt), which generated a GHG emission reduction of 16.9 Mt of CO₂ equivalent and a CAP emission reduction of 1.8 Mt in 2015. Given the significant contribution of NGVs, growing the NGV population in 2020 will further increase the petroleum substitution benefits and CAP and GHG emission reduction benefits by approximately 42.5 Mt of petroleum-based fuel, 3.1 Mt of CAPs and 28.0 Mt of GHGs. By 2030, these benefits will reach 81.5 Mt of traditional petroleum fuel, 5.6 Mt of CAPs and 50.5 Mt of GHGs, respectively.     

Traffic impacts of international roaming on mobile and personal communications with distributed data management

In this paper, we propose four network interconnection scenarios and the related signaling aspects for the international roaming traffic in mobile and personal communications. With or without international gateway relay nodes summarized from the proposed scenarios, we also derive three international roaming network sets {IR₁, IR₂, IR₃} for the observed signaling traffic model with twolevel databases. Based on the proposed performance metrics, analysis results show that under some reasonable assumptions the signaling traffic of international roaming is significantly impacted by the related gateway relay nodes and databases. In addition, the studied cache data management strategy at VLR can reduce the impacts of the signaling traffic of query operation, but the caching approach cannot improve the performance of update operation. Furthermore, the performance of proposed standalone STP scenario is better than that of integrated STP scenario for the international network connection.     

高速钢激光重熔后的组织与性能

研究了W18Cr4V高速钢激光重熔后的组织与性能。结果表明，常规淬回火组织经激光重熔后其硬度、韧性都有提高，熔化层的残余应力为技应力；经640℃回火后；由于残余应力的消除及重熔组织中马氏体的二次硬化和残余奥氏体的二次淬火效应其耐磨性能有了进一步地提高。     

邮电通信对信息化适应问题浅析

信息化是社会发展的必然要求，适应信息化的要注是邮电通信发展的一个基本目标。本文采取国际上较为通用的分析方法研究了中国邮电通信对信息化的适应程度，并结合通信发展中现存问题对今后发展提出应引以注意的方面。     

利用ATM构造宽带INTERNET骨干网

本文分析了传统的Ｉｎｔｅｒｎｅｔ骨干网的组网方案纯路由器网络的成功及其所面临的挑战，提出在网络核心引入交换技术，通过采用ＡＴＭ构造带宽Ｉｎｔｅｒｎｅｔ骨干网，可以构更大规模的网络，使网络运营者受益，并且为将来Ｉｎｔｅｒｎｅ提供综合业务奠定坚实的基础。     

全球电信界的战略联盟

９０年代初，随着通信向全球化方向发展，发达国家各电信企业纷纷采用联盟的方式，相互联合，发挥各自优势，大举进军全球电信市场。面对这种联盟潮流，想要搭上全球通信的列车，发展中国家应该采取什么措施？坚持什么原则？本文作者对此进行了较深入的分析和研究，并对中国电信的发展提出了建议。     

在线近红外光谱分析仪在汽油自动调合系统中的应用

在线近红外光谱分析仪可以实时测定汽油调合组分及成品油的多种物化性质指标如烯烃、芳烃、苯及氧化物含量、辛烷值（RON、MON）、馏程、蒸气压等。文章介绍了用于汽油自动调舍工艺中的在线近红外光谱分析仪的原理、系统组成和特点，以及在国内外的汽油调合优化控制中的实际应用情况。典型的应用实例表明，将该分析仪用于汽油自动调合工艺中，可为炼油厂带来可观的经济效益和社会效益。     

高油价下我国石油化工的发展对策思考

改革开放20多年来，中国经济向全球展示了持续快速的增长，作为支柱产业的中国石化工业也一直保持着良好的增长势头，得到了稳定快速的发展，尤其在“十五”期间，中国的石化工业在世界石化业中的地位有了突破性的提升。