Safety-based path finding in urban areas for older drivers and bicyclists

This paper presents a safety-based path finding methodology for older drivers and bicyclists in an urban area. The paths are estimated based on costs consisting of both safety and travel time. Safety is evaluated against potential risk of a crash involving an older driver (or a bicyclist) with other vehicles present on the road. To accomplish this, simple formulations are developed for safety indicators of streets and intersections, which are actually generic irrespective of the type of road user. Traffic attributes such as speed and density, driver attributes such as perception-reaction time and street attributes of length and tire-to-road friction coefficient are taken into account in building the safety indicators. Thus, the safety indicators do not necessarily require historical crash data which may or may not be available during path finding. Subsequently, a multi-objective shortest path algorithm is presented that identifies the best path (the non-inferior path) from amongst a set of selected safest paths with due considerations to travel time incurred on each. A simple application example of the proposed methodology is demonstrated on an existing street network system from the City of College Station, Texas. The contributions of this research are twofold – first, the safety indicators can be used by planners in determining high crash potential sites – streets and/or intersections – and second, the safety-based path finding methodology developed in this paper can be integrated with modern day route planning devices and tools in guiding older drivers and bicyclists within an Intelligent Transportation Systems framework.     

驼峰ZK4转辙机锁闭阀电源设置

在旧驼峰站场上安装新型ZK4转辙机,要增设一组直流24V电源供锁闭阀使用,根据站场特点,采用了分散供电方式,既能保证道岔的正常运用,又大大地节约了成本。     

二乘二取二安全控制平台开发

二乘二取二安全控制平台包括二乘二取二逻辑运算单元,二取二开关量输入、输出单元,人机接口单元。逻辑运算单元由2块独立的CPU板构成二取二结构,2块CPU板通过板上硬件同步单元实现信息交互和同步,在软件上独立进行运算结果的比较,并通过第三方硬件比较器实现2块CPU板总线数据的实时校核,保证了双CPU比较的正确性。输入单元和输出单元中均设计了双套智能处理器,采用动态控制方式,在出现硬件故障时可导向安全侧。其中输入单元对现场继电器前后接点进行采集,输出单元输出采用双断方式,可实时检测板外混电情况。     

铁路货物装卸作业安全分析与管理实践

北京铁路局唐山站装卸分公司在日常安全检查中,找准问题,分清原因,对症下药,解决问题。通过推行安全风险管理,加强制度建设,加强素质培训,加强过程控制,加强设备管控,强化全员的安全风险意识及安全考核等对策的实施,在安全管理中贯彻安全风险管理,取得了较好效果。     

能见度不良时的"安全航速"和船长职能

为确保航海安全和各方的利益,当能见度不良时在公海和沿海渔区如何控制安全航速及船长的职能。     

基于停车视距的高速公路雨天行车安全车速研究

考虑低能见度及路面附着系数减小的情况,研究了高速公路雨天的安全车速.从跟车状态下停车过程出发,根据不同的水膜厚度得出其对应的附着系数,进行了基于AASHTO停车视距模型的高速公路安全车速计算.并应用于湖北省黄黄高速公路雨天交通管理措施,供相关技术人员参考.     

基于Web服务的工作流系统的架构及应用研究

在工作流系统中,结合Web服务技术,有效解决了目前工作流系统与外部系统的交互问题.介绍工作流技术和Web服务,提出基于Web服务的工作流结构模型,最后以铁路局安全管理信息系统为例说明该模型的应用.     

加强设备安全管理确保船舶安全运营

船舶安全管理是船公司管理的主要部分,设备安全管理是贯穿船公司安全管理的一项重要内容,是一项综合系统性管理工作。做好船舶设备安全管理工作,可以从建立完善设备安全管理体制、加强船员管理力度、加强和推行质量管理、重视设备维修保养工作以及培育企业安全文化等方面开展工作。     

Microscopic driving theory with oscillatory congested states: Model and empirical verification

The essential distinction between the Fundamental Diagram Approach (FDA) and Kerner’s three-phase theory (KTPT) is the existence of a unique gap–speed (or flow–density) relationship in the former class. In order to verify this relationship, empirical data are analyzed with the following findings: (1) linear relationship between the actual space gap and speed can be identified when the speed difference between vehicles approximates zero; (2) vehicles accelerate or decelerate around the desired space gap most of the time. To explain these phenomena, we propose that, in congested traffic flow, the space gap between two vehicles will oscillate around the desired space gap in the deterministic limit. This assumption is formulated in terms of a cellular automaton. In contrast to FDA and KTPT, the new model does not have any congested steady-state solution. Simulations under periodic and open boundary conditions reproduce the empirical findings of KTPT. Calibrating and validating the model to detector data produces results that are better than that of previous studies.     

谈船舶检验部门在水上安全监管中的管理责任

通过对船检部门在水上安全监管中存在问题进行分析,探索地方船检工作由被动检验到主动监管转变的途径,提出地方船检在水上安全监督管理中发挥作用的建议,这个途径就是落实责任,责任是质量,责任是创新,责任是效能,责任是船检工作的立命之本。