尾气加热式水暖系统在城市客车上的应展

简述了城市客车尾气加热式水暖系统的特点、工作原理，提出在设计过程中的注意事项。     

开展铁路工程地质勘察监理的程序

铁路工程地质勘察监理已实施一段时间,笔者先后参加了襄渝线、包西线、襄石线等勘察监理工作,对勘察监理有着较深的体会。下面就监理工作的开展程序做一下介绍,希望对今后的工程地质勘察监理工作的开展提供一定的借鉴。     

Hybrid Electric Drive for DDG-51 Class Destroyers

The first of the Arleigh Burke class destroyers is nearing its mid-life. This class of ships was designed during the late 1970s through the 1980s to meet the threats that were prevalent at that time. Since entering service in 1991, these ships have shown themselves to be extremely versatile and the class now consists of nearly 60 ships in service. Their combat systems have been continually upgraded and adapted to meet the new threats the United States faces today. However, in order to keep these platforms viable throughout the first half of the 21st century, their operating costs must be reduced. Manpower, maintenance, and fuel are three of the top operating cost drivers. Most surface combatants spend very little of their underway time operating at full speed or even close to that. Over 1/3 of their underway time is spent at 12 knots and under. This is less than half of their maximum speed and only a fraction of the maximum power owing to the cubic speed–power relationship. Although the existing mechanical drive system is reasonably efficient, the main gas turbines are extremely inefficient at these very low power levels. A shaft-mounted auxiliary electric propulsion system (EPS) can take advantage of excess capacity in the ship service generators to reduce the main engine operating hours. Enabling bi-directional power flow from this auxiliary electric drive will provide additional generation capacity for ship service loads at a modest additional cost. It also provides a "cross-connect" capability from one shaft to the other. This paper will explore one prospect for reducing the operating cost of the DDG-51 class of ships by installing an auxiliary EPS that would powered by the ship service electrical plant. This additional system would serve to reduce both underway fuel usage as well as maintenance on the gas turbine main engines by reducing the number of operating hours on each engine. We will examine the technology trade-offs in this ongoing study.     

Environmental trends of ports and harbours: Implications for planning and management

The traditional view of ports as evolving from human settlements to distribution centres is re-examined in an ecological context. The discussion is essential because of the persisting traditional approach to 'global' port development, i.e. directed primarily by technological optimization related to cargo transfer and ocean trasportation. Growing environmental concerns and realities indicate the need for a broader environmental view in which the port is recognized as part of a larger interactive coastal ecosystem, with environmental pressures by the port on the surrounding environment, as well as by the environment on the port. The paper argues for an ecological basis for coastal port development, analyses the environment implications of riverine linkages between port and hinterland, and details some environmental consequnces of changing industrialization and chemical practices. It also identifies initiatives for relevant planning and future port management.     

Regional impacts of new transport infrastructure: a multisectoral potentials approach

This is the second of two background papers sponsored for the Symposium by the Administrative Commission for the north of the Netherlands. Its purpose is to provide an indication of the effects of the proposed high speed rail line between Amsterdam, Groningen and Hamburg on employment in the corridor. The authors first review the techniques of forecasting these effects discussed in the literature. The potentials approach is adopted for their analysis, the mathematics and underlying assumptions of which are presented. Finally, this model is run to provide an estimate of the impact on regional employment of three variants of the proposed rail line.     

车载列控EMC监测系统在信号动态检测中的应用

基于EMC技术的车载列控运行环境电磁干扰监测系统应用于信号动态检测中,实现对列控系统天线附近电磁环境的监测和车载列控设备电磁干扰的实时测试及分析,能够辅助分析车载列控设备出现的问题。     

土压平衡盾构在复合地层中带压进仓施工技术

结合南京地铁土压平衡盾构在复合地层中带压进仓的具体情况,通过采取带压进仓压力计算、现场试验压力确定以及实施过程,成功地解决了土压平衡盾构进行带压进仓作业,了解掘进面存在的问题以及解决方式等技术难点.通过对监测数据的对比、分析,说明该方法的可行性及合理性,为土压平衡盾构在复合地层中带压进仓的施工提供参考与借鉴.     

城市轨道交通车站站前折返间隔分析

以不同折返过程对站前折返间隔进行了较详细的分析.从单线折返和双线折返两个方面测算出站前折返的折返间隔,并从运营角度,测算了所需的停站时间.分析了单线折返、双线折返的非等间隔折返、双线折返的等间隔折返各自的优缺点.通过对站前折返影响因素的分析,从设计和应用角度,提出了尽可能缩短站前折返间隔的措施和办法.     

CBTC系统基于站台局域无线覆盖的后备控制等级功能扩展

讨论目前CBTC系统中不同等级后备模式的工作原理及存在的功能缺陷,提出了一种在现有系统上增加站台区域车-地双向无线通信覆盖以实现站区紧急停车防护和站台屏蔽门控制的技术解决方案。     

国产MTC-I型CBTC系统的安全认证实践与探讨

重点围绕城市轨道交通国产MTC-I型列车控制系统（CBTC）独立第三方安全评估与认证工作,阐述了信号安全攸关系统的技术标准规范体系、安全完整度等级、安全认证类型、风险评价原则等概念与定义。基于安全认证、系统生命周期、安全保障架构、项目风险管理、安全审核与评估等具体内容描述了MTC—I型CBTC系统通用产品安全认证实践过程。对建立我国城轨交通行业发展的安全认证体系、实施策略以及风险管控原则等安全认证要素进行了分析与探讨。