短波通信设备综合检测系统硬件设计方案

针对短波通信设备现场应急维修保养的特点,设计了一种短波综合检测系统,目的在于为短波通信设备的现场维修提供一种便捷手段。     

基于公交优先的城市和谐交通发展双E推模式

基于公交优先的城市和谐交通发展双E推模式是依据当前我国城市交通现状提出的切实可行的策略模式,主要包括政府推动力和企业推动力。     

Vehicular Ad-Hoc Networks sampling protocols for traffic monitoring and incident detection in Intelligent Transportation Systems

Vehicular Ad-Hoc Networks (VANETs) are an emerging technology soon to be brought to everyday life. Many Intelligent Transport Systems (ITS) services that are nowadays performed with expensive infrastructure, like reliable traffic monitoring and car accident detection, can be enhanced and even entirely provided through this technology. In this paper, we propose and assess how to use VANETs for collecting vehicular traffic measurements. We provide two VANET sampling protocols, named SAME and TOME, and we design and implement an application for one of them, to perform real time incident detection. The proposed framework is validated through simulations of both vehicular micro-mobility and communications on the 68 km highway that surrounds Rome, Italy. Vehicular traffic is generated based on a large real GPS traces set measured on the same highway, involving about ten thousand vehicles over many days. We show that the sampling monitoring protocol, SAME, collects data in few seconds with relative errors less than 10%, whereas the exhaustive protocol TOME allows almost fully accurate estimates within few tens of seconds. We also investigate the effect of a limited deployment of the VANET technology on board of vehicles. Both traffic monitoring and incident detection are shown to still be feasible with just 50% of equipped vehicles.     

Modeling the information flow propagation wave under vehicle-to-vehicle communications

Vehicle-to-vehicle (V2V) communications under the connected vehicle context have the potential to provide new paradigms to enhance the safety, mobility and environmental sustainability of surface transportation. Understanding the information propagation characteristics in space and time is a key enabler for V2V-based traffic systems. Most existing analytical models assume instantaneous propagation of information flow through multi-hop communications. Such an assumption ignores the spatiotemporal relationships between the traffic flow dynamics and V2V communication constraints. This study proposes a macroscopic two-layer model to characterize the information flow propagation wave (IFPW). The traffic flow propagation is formulated in the lower layer as a system of partial differential equations based on the Lighthill-Whitham-Richards model. Due to their conceptual similarities, the upper layer adapts and modifies a spatial Susceptible-Infected epidemic model to describe information dissemination between V2V-equipped vehicles using integro-differential equations. A closed-form solution is derived for the IFPW speed under homogeneous conditions. The IFPW speed is numerically determined for heterogeneous conditions. Numerical experiments illustrate the impact of traffic density and market penetration of V2V-equipped vehicles on the IFPW speed. The proposed model can capture the spatiotemporal relationships between the traffic and V2V communication layers, and aid in the design of novel information propagation strategies to manage traffic conditions under V2V-based traffic systems.     

UHF移动通信技术在汽车分队指挥中的应用展望

分析了汽车分队信息化指挥通信系统的现状,指出了当前该领域在实践运用过程中存在的薄弱环节,介绍了UHF移动通信技术的优势,提出了将UHF通信技术运用于汽车分队指挥领域的设想,为进一步完善信息化指挥体系、推动汽车运输分队保障能力建设迈上新台阶提供技术支撑。     

LKD1-T型列控中心的工程接口和现场调试方法

LKD1-T型列控中心是全路使用最广的既有线列控中心设备。本文介绍了LKD1-T型的工程接口，针对列控中心开通的准备工作和现场调试方法进行了详细阐述，对于帮助和指导现场人员和施工单位、电务工作人员熟悉列控中心设备原理，进行现场开通调试，具有一定指导意义。     

CTCS-2列车运行控制系统问题

简要介绍CTCS-2级列车运行控制系统的若干问题,分析一些常见的故障,针对这些问题提出相应的解决方案和改善措施。主要阐述临时限速问题、ATP车载设备问题以及常见的列控系统地面设备故障,概述常见接口故障。     

基于TCN技术的内燃动车组列车通信网络

介绍了内燃动车组列车控制与通信网络(TCN)的拓扑结构及其组成、通信及重联控制,阐述了各主要部件的功能。     

舰船无线电通信的抗干扰技术

介绍舰船无线电通信的抗干扰技术，包括高频自适应通信技术、跳频及扩频通信技术、自适应、自组织、自恢复通信网等。     

浅谈我省交通工程造价管理趋势

讨论了我省工程造价管理模式在工程建设市场中的作用,它的合理性以及发展的趋势并提出几点建议和看法,仅供参考。