Paradoxes of rationality in road safety policy

Rationality is an ideal for transport safety policy. As developed within normative welfare economics, rationality denotes the efficient use of safety measures based on cost–benefit analyses that include all relevant impacts of the measures. Efficiency in the technical sense of the term provides a perfectly clear and precise guideline for policy priorities. Nevertheless, some choices that are guided by cost–benefit analysis may strike us as paradoxical or counterintuitive. A paradox of rationality refers to any situation in which conflicting choices can both be defended as rational. This paper discusses a number of choices that may seem paradoxical. The first involves the choice between options that have identical impacts on safety, but in which these impacts are valued differently. The second deals with the tendency for preference reversals to occur when preferences for the provision of safety are aggregated. The third discusses the inability of conventional measures of willingness-to-pay to reflect the intensity of preferences. The fourth concerns the tendency for policy choice to favour the rich at the expense of the poor when willingness-to-pay is not adjusted for the marginal utility of money. A fifth situation refers to the fact that a policy option that looks attractive ex ante may fail an ex post compensation test because utility functions depend on health state. There is a potential conflict between individual and collective rationality with respect to the costs and benefits of some road safety measures. When developing a road safety programme, a set of road safety measures whose benefits exceed the costs when considered as stand-alone measures could have benefits smaller than cost when combined in a programme consisting of all the measures. Finally, there is a potential conflict between efficiency and negotiated consensus as mechanisms of resource allocation in the public sector. The sources of the paradoxes and ways of avoiding them are discussed. Some of the paradoxes can be avoided if changes in risk are valued in terms of a fixed price per unit of risk rather than according to a non-linear demand function.     

Comparing the fatality risks in United States transportation across modes and over time

This paper analyzes the transportation fatality risk in the United States. The analysis is in two parts. The first part compares the relative risks of the different modes based on data for the decade from 2000 to 2009. The second part is a time-series analysis for each mode using annual data from 1975 to 2010. By almost any measure, transportation is considerably safer now than it was in the mid 1970s. The improvement is especially noticeable for commercial modes such as aviation, railroads and maritime. Even the risks from private highway driving have halved during the past thirty-five years.     

Modeling yard crane operators as reinforcement learning agents

Due to the importance of drayage operations, operators at marine container terminals are increasingly looking to reduce the time a truck spends at the terminal to complete a transaction. This study introduces an agent-based approach to model yard cranes for the analysis of truck turn time. The objective of the model is to solve the yard crane scheduling problem (i.e. determining the sequence of drayage trucks to serve to minimize their waiting time). It is accomplished by modeling the yard crane operators as agents that employ reinforcement learning; specifically, q-learning. The proposed agent-based, q-learning model is developed using Netlogo. Experimental results show that the q-learning model is very effective in assisting the yard crane operator to select the next best move. Thus, the proposed q-learning model could potentially be integrated into existing yard management systems to automate the truck selection process and thereby improve yard operations.     

连栋棚室自动控制及远程监测

针对连栋棚室内环境参数经常变化且存在一个作物最适宜生长的参数范围,本文设计了一种对连栋棚室内温度、湿度、光照、CO2浓度等参数进行自动化控制和远程监测的系统.系统以ATmega16为核心,依托GSM网络为远程通讯信道,能实现管理人员远程查询、自动调节环境参数、系统故障短信报警这三大功能.仿真结果表明：该系统的设计方案是合理的,具有性价比高,结构简单,实用性强等优点,为提高单位生产率和推广连栋棚室做出了贡献.     

CORS在公路测量中的应用

随着连续运行GPS参考站技术的不断发展,网络RTK的优势不断体现出来。文章结合内蒙古全球导航卫星连续运行参考站综合服务系统网（NMGCORS）的建设,陈述了网络RTK的原理及Trimble R8 GPS如何进行网络RTK设置,希望对相关技术人员有参考作用。     

圆锥形管道中的瞬变流分析

根据非稳定流的一维流动理论,对圆锥形管道中的瞬变流动进行了分析,推导出了适用于圆锥形管道的连续性微分方程和运动微分方程,给出了这两个方程的有限差分解法,同时对计算结果进行了相对误差的对比分析。分析结果说明,采用该方法来进行分析计算可以有效地减小误差。     

基于GPS、GIS与GSM开发车辆监控调度系统的研究

论述了基于GPS、GIS与GSM开发车辆监控调度系统的主要内容与关键技术，包括车载GPS定位数据处理、GIS中用于车辆监控调度的电子地图的制作方法、数据通信等。最后结合实际开发工作给出了实现系统主要功能的编程思路。     

基于GSM通信的电力远动SCADA系统在国外铁路项目中的设计研究

根据电力远动SCADA系统的特点并结合国外铁路现状和项目要求,研究设计了一种基于GSM通信方式的电力远动SCADA系统。基于GSM通信的电力远动SCADA系统主要由SCADA系统主站、GSM通信单元、增加了自适应天线的RTU组成。采用GSM方式接收的电力远动SCADA系统能够在复杂的山地环境和有线方式建设较困难的部分区域保证数据的可靠发送/接收,具有良好的经济性和适用性。     

趋势项分离预测模型及重标度极差分析在深基坑变形预测中的应用研究

为解决基坑变形预测精度低的问题,利用小波去噪和卡尔曼滤波对基坑变形序列进行去噪处理,分离趋势项及误差项,并利用支持向量机和BP神经网络分别对趋势项和误差项进行预测,以掌握基坑的变形规律及发展趋势;同时,采用重标度极差分析(R/S分析)对基坑的变形趋势进行判断,以验证变形预测的可靠性。根据实例检验,得出小波去噪的去噪效果较好,且预测结果的相对误差均值为1.03%,方差值为0.083,预测精度较高;基坑的变形序列与速率序列均具有持续增长的趋势特征,与变形预测结果一致,验证了预测思路的有效性。     

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概要介绍了Internet 地图应用的情况，并讨论了它在车辆监控系统中的一个具体应用. 首先根据Internet 地图应用所提供的服务与所采用的技术，提出了一种为它们分类的方式. 然后基于前面的讨论，介绍了作者实现的一种Internet 地图应用——Web-VehicleSuper，一个基于GPS、GSM、WebGIS 的车辆监控系统. 由于采用了面向对象的编程技术及分布式的应用结构，本系统具有很好的灵活性与扩展性，符合WebGIS 的发展方向，并在系统性能与使用成本之间取得了比较好的折衷. 从实践来看，本系统完全能够满足小容量车辆监控系统的需要.