Driver detection and recognition of lineside signals and signs at different approach speeds

A study was carried out using simulation to investigate driver responses to lineside signals and signs at various approach speeds. The objectives of the study were: (1) to find out whether train speed would significantly affect signal/sign reading; (2) to examine at which point certain types of signs or signals could be detected or recognised, and (3) to determine a speed cut-off level above which certain types of signs or signals are no longer recognisable or detectable. Fifty-seven train drivers from 12 Train Operating Companies in the UK participated in the trials. Twenty different types of lineside signs and ten types of signals were tested under six different approach speeds ranging from 100 to 350 km/h (62–218 mph). Driver performance measures were ‘time remaining to the signal/sign’ at the point of detection or recognition, and reading error rate. The results showed a significant influence of train speed on driver responses to lineside signals/signs and demonstrated a non-linear relationship between driver responses to signals/signs and approach speed. This has been used to estimate a maximum approach speed limit within which a specific signal or sign can be correctly detected or recognised. The findings and implications of the study are discussed in the paper.     

预处理工艺对硬质合金与金刚石膜间粘结力的影响

在两种经不同预处理的硬质合金YG8基底上，采用微波等离子体化学气相沉积法，在微波功率2kW，压强4.0kPa和6.5kPa，CH4和H2流量分别为1.6cm/s和100.0cm/s的条件下生长金刚石薄膜。利用X射线衍射检测了金刚石薄膜是否存在，用拉曼光谱分析了薄膜的质量，用金相显微镜观察了薄膜的洛氏硬度压痕，标定并比较了不同预处理工艺膜与基底的结合力。实验结果表明，不同的预处理方法对于粘结力的影响不大，最主要的因素是钴含量的多少。     

The Solutions for Adjustment and Reconstruction of Water-Drive Surface Systems in the Old Areas of Daqing Oilfield

Introduction 　　Owing to long-time running, more facilities including stations, pipelines, vessels have become corrosive and aged ,some process has grown old, it has exert more burden for the maintenance and repair.Simultaneously, the fluid production rate, oil production rate and water injection rate has changed greatly so that the inflicts and problems from the established surface systems will become more obvious. Energy cost of production and running has increasing continuously. Capacity has been unbalance in systems and areas. 　　……     

高速往复式内燃机平衡轴低质量设计分析

分析了扇形和偏心圆两种平衡轴设计的要求以及平衡重低质量的设计原则。扇形平衡重半径及宽度应尽量大、夹角应尽量小。偏心圆平衡重的偏心圆半径应尽可能大 ,轴承半径应尽可能小。同样质量的扇形平衡重产生的平衡力比偏心圆平衡重要大。     

莺-琼盆地生物气及生物—低成熟过渡带气特征与勘探前景

莺 琼盆地天然气资源丰富 ,天然气成因类型多 ,迄今为止 ,除在该区浅层和中深层发现以成熟—高成熟的热成因腐殖型气 (煤型气 )为主的天然气藏外 ,也发现了一些生物气及生物—低成熟过渡带气气藏 ,且均具较高的产量和一定的储量规模 ,其勘探前景广阔。     

环境中氚和碳-14

本文介绍了加拿大恰克河实验室有关氚和碳－14在环境中行为和评价的研究。     

关于粒子加速器人身辐射安全联锁系统设计原则的建议

本文讨论了在粒子加速器上的联锁系统设计中应遵循的一些原则,其中建立隔离区、“失效导致安全(Fail-safe)”,使用“硬件”、“多重联锁”、设置急停开关等是最重要的。     

Seasat over-land scatterometer data. I. Global overview of theKu-band backscatterer coefficients

Statistics on the backscatter coefficient σ⁰ from the Ku-band Seasat-A Satellite Scatterometer (SASS) collected over the world's land surfaces are presented. This spaceborne scatterometer provided data on σ⁰ between latitude 80° S and 80° N at incidence angles up to 70°. The global statistics of vertical (V) and horizontal (H) polarization backscatter coefficients for 10° bands in latitude are presented for incidence angles between 20° and 70° and compared with the Skylab and ground spectrometer results. Global images of the time-averaged V polarization σ⁰ at a 45° incidence angle and its dependence on the incidence angle are presented and compared to a generalized map of the terrain type. Global images of the differences between the V an H polarization backscatter coefficients are presented and discussed. The most inhomogeneous region, which contains the deserts of North Africa and the Arabian Peninsula, is studied in greater detail and compared with the terrain type     

一种基于策略的网络管理结构方案

介绍了基于策略的网络管理的概念和当前的研究状况，在策略定义、冲突检测和系统安全问题等方面进行了讨论，提出了一种适合基于策略的网络管理的结构方案，并分析了该方案的合理性。