特种装备项目的节能评估方法研究

特种装备的购置及改造项目属于固定资产投资范畴,在审批环节中应进行节能审查。本文以科学考察船为例,基于分析科学考察船与其他类固定资产的不同,阐述了科学考察船建设方案的节能评估、能源消费种类及能耗测算方法,并就评估过程中存在的问题提出了相关建议。     

Autonomous cars: The tension between occupant experience and intersection capacity

Systems that enable high levels of vehicle-automation are now beginning to enter the commercial marketplace. Road vehicles capable of operating independently of real-time human control under an increasing set of circumstances will likely become more widely available in the near future. Such vehicles are expected to bring a variety of benefits. Two such anticipated advantages (relative to human-driver vehicle control) are said to be increased road network capacity and the freeing up of the driver-occupant’s time to engage in their choice of leisurely or economically-productive (non-driving) tasks.In this study we investigate the implications for intersection capacity and level-of-service of providing occupants of automated (without real-time human control), autonomously-operating (without vehicle-to-X communication) cars with ride quality that is equivalent (in terms of maximum rates of longitudinal and lateral acceleration) to two types of rail systems: [urban] light rail transit and [inter-urban] high-speed rail. The literature suggests that car passengers start experiencing discomfort at lower rates of acceleration than car drivers; it is therefore plausible that occupants of an autonomously-operating vehicle may wish to instruct their vehicle to maneuver in a way that provides them greater ride comfort than if the vehicle-control algorithm simply mimicked human-driving-operation.On the basis of traffic microsimulation analysis, we found that restricting the dynamics of autonomous cars to the acceleration/deceleration characteristics of both rail systems leads to reductions in a signalized intersection’s vehicle-processing capacity and increases in delay. The impacts were found to be larger when constraining the autonomous cars’ dynamics to the more-restrictive acceleration/deceleration profile of high-speed rail. The scenarios we analyzed must be viewed as boundary conditions, because autonomous cars’ dynamics were by definition never allowed to exceed the acceleration/deceleration constraints of the rail systems. Appropriate evidence regarding motorists’ preferences does not exist at present; establishing these preferences is an important item for the future research agenda.This paper concludes with a brief discussion of research needs to advance this line of inquiry.     

广西交通科技资源共享平台建设探讨

文章针对广西交通科技项目管理系统现状,分析了建设交通科技资源共享平台的必要性,阐述了交通科技资源共享平台建设的关键技术、创新点及主要内容,指出该共享平台的建设可改善和提高交通运输科技项目质量及监管水平。     

国外钢板在轿车发展中的作用

本文从法规限制，市场需求和生产制造等方面评述了轿车工业面临的压力，论述了钢板用于制造轿车壳体的特点，根据轿车材料的选择原则，无论是近期还是未来，钢板仍将是轿车壳体的主要材料。针对轿车壳体的应用，简述了薄钢板，镀层钢板和复合夹层减振钢槔的现状和发展趋势。     

基于模型的现代汽车电子系统开发和测试

基于模型的汽车电子系统开发的核心是利用计算机仿真技术建立一个虚拟的汽车电子系统开发平台,该虚拟平台的开发包括模型开发和测试方法开发.针对各电控单元的性能指标可开发其仿真模型,程序代码由仿真模型自动转换产生.以汽车仪表盘的测试为例,对整个测试过程做了介绍.     

Guidance for transport planning and policymaking in the face of an uncertain future

Uncertainty of outcome is widely recognised as a concern facing decision-makers and their advisors. In a number of spheres of policy, it appears uncertainty has intensified in the face of globalisation, economic instability, climate change, technological innovation and changing consumer preferences. How can planners and policymakers plan for an uncertain future? There is growing interest in, and use of, techniques that can help decision-making processes where deep uncertainty is involved. This paper is based upon one of the most recent international examples of a foresight exercise employed to examine uncertainty – specifically that which concerns uncertainty over the nature and extent of future demand for car travel. The principal focus of the paper is on the insights and guidance this examination of uncertainty brings forth for transport planning and policymaking. To accommodate deep uncertainty requires a flexible and open approach in terms of how policy and investment possibilities are formulated and judged. The paper argues for a focus upon the Triple Access System of spatial proximity, physical mobility and digital connectivity as a framework for policy and investment decisions that can harness flexibility and resilience. Uncertainty becomes an opportunity for decision-makers with the realisation that they are shaping the future rather than (only) responding to a predicted future. The paper outlines two forms of policymaking pathway: regime-compliant (in which adherence to trends and the nature of the world we have known pushes policy) and regime-testing (in which the nature of the world as we have known it is brought into question and vision pulls policy decisions). Stronger orientation towards regime-testing to assist in managing an uncertain future is advocated.     

货车轮对的运用可靠性

分析了货车轮对在运用中出现故障的原因,提出了提高轮对使用期限的方法和轮对修复的具体措施。     

70 t级新型通用货车制动系统方案探讨

针对70t级新型通用货车对制动系统的要求,分析了现有制动系统的不适应性,并提出了新型制动系统的构想。     

Travel time estimation from sparse floating car data with consistent path inference: A fixed point approach

Estimation of urban network link travel times from sparse floating car data (FCD) usually needs pre-processing, mainly map-matching and path inference for finding the most likely vehicle paths that are consistent with reported locations. Path inference requires a priori assumptions about link travel times; using unrealistic initial link travel times can bias the travel time estimation and subsequent identification of shortest paths. Thus, the combination of path inference and travel time estimation is a joint problem. This paper investigates the sensitivity of estimated travel times, and proposes a fixed point formulation of the simultaneous path inference and travel time estimation problem. The methodology is applied in a case study to estimate travel times from taxi FCD in Stockholm, Sweden. The results show that standard fixed point iterations converge quickly to a solution where input and output travel times are consistent. The solution is robust under different initial travel times assumptions and data sizes. Validation against actual path travel time measurements from the Google API and an instrumented vehicle deployed for this purpose shows that the fixed point algorithm improves shortest path finding. The results highlight the importance of the joint solution of the path inference and travel time estimation problem, in particular for accurate path finding and route optimization.     

捷达系列轿车中央门锁与防盗系统的检修

介绍捷达系列轿车的中央门锁与防盗系统的结构组成与原理,并对系统可能产生的故障以及如何诊断维修加以探讨。