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1.
Rail signal systems have traditionally been employed to prevent collision of trains while permitting them to adhere to a schedule that is adequate for moving passengers and/or freight. In today's rapid-transit systems, however, the corollary objectives of a signal system?namely, controlling the speed of trains, increasing the capacity of the line, and minimizing schedule disruptions caused by transient disturbances in train operations?are critical to providing satisfactory service to passengers. 相似文献
2.
Ambitious improvements in rail transport and commercial aviation slated by the 12 members of the European Community (EC) for 1992 and beyond are discussed. Most publicized has been the Folkestone-to-Calais tunnel (actually three 50-km tunnels) beneath the English Channel. The tunnel is to open in June 1993, with high-speed trains operating about every five minutes, carrying passengers, their cars, and other cargo. Other plans underway will culminate in a high-speed rail network extending throughout the EC and perhaps into Eastern Europe. The European Commission, the EC's executive arm, is to develop plans by the end of the year for the network, which will span 19000 to 30000 km of existing and still-to-be-built track. In the air, the emphasis is on control. A unified system controlling the upper airspace was the goal of Eurocontrol, founded by European civil aviation authorities in 1963, but it has yet to come about. Eurocontrol has established a European Coordination Team to find quick ways of improving the existing airspace capacity; it is also managing a program to create operational and technical standards for both air-traffic control equipment and facilities to which all Eurocontrol members must eventually adhere. The most volatile area of the transportation market is the automotive segment, with the burning issue being cars from Japan. No major technical advances are foreseen in European cars in the near future 相似文献
3.
为满足快速增长的旅客运输需求,国家“十一五”规划了“四纵四横”铁路快速客运通道以及3个城际快速客运系统,时速高达380 km/h。随着列车时速的不断加快,车厢内手机用户通信时发生切换混乱、接通率低和掉话等现象,无线网络覆盖面临挑战。文章立足于高铁专网设计总体目标,基于高速移动通信性能影响因素,采用分布式基站和一体化基站,提出一种高速铁路组网方案。 相似文献
4.
《IEE Review》1989,35(5):171-174
The Hong Kong mass transit railway (MTR) was designed to have four routes, of which three are in service so far. It has 39 km of double track and 37 stations and carries up to 90000 passengers per hour in each direction under crush conditions. Design of the system is therefore vital in terms of safety and the stations, trains and power supplies are discussed while considering this aspect 相似文献
5.
Faster than a speeding bullet train 总被引:1,自引:0,他引:1
《Spectrum, IEEE》2003,40(8):30-34
China is throttling up a 430-km/h magnetically levitated train to link Shanghai and its airport. Built in China by a trio of German companies and the Shanghai Maglev Transportation Development Co., it reaches 430 km/h (268 mi/h)-130 km/h faster than Japan's famous bullet train. And even as it goes faster than any commercial vehicle without wings, the Chinese train is smoother and quieter than Amtrak's wheel-on-rail Acela-the state of the art in the United States-which pokes along when it can at a maximum 240 km/h. After many false starts and the completion of full-scale experimental maglev systems in Japan and Germany in the 1980s, maglev in China will finally start shuffling passengers in October in a reasonably large-scale, commercial system. The trains will run from downtown Shanghai's financial district to Pudong International Airport, making a 9-minute run that will shave about 40 minutes off the typical trip time in a taxi. With three five-car trains, each carrying as many as 574 passengers, and trains leaving every 10 minutes, the US $1.2 billion system could carry more than 10 million passengers a year. 相似文献
6.
When oceanborne transportation is mentioned, one reaction is to think of the "decline of the merchant fleet" and "outmoded" ships. Such opinions may be partially correct if applied to a few segments of the world's merchant fleet, but nothing could be further from the truth than to apply such geaeralizations to the total world picture. Oceanborne transportation was and still is for all practical purposes the key to world trade and in spite of the rapid development of air transportation, in the foreseeable future it will carry the vast majority of goods in world trade both in terms of value of cargo and cargo tonnage. Oceanborne trade is expanding very rapidly and with its growth the efficiency of operations in meeting increasing demands becomes of ever-increasing importance. It is obvious that operations research and systems analysis have to be applied to oceanborne transportation becanse it is but one leg of a larger transportation system. As a result of this application, we see a revolution in oceanborne transportation which will bring with it many changes in traditional patterns. Some ships are becoming much larger and others are becoming both larger and faster; shipboard automation is being introduced; but the most important changes of all are taking place in methods for cargo handling. Not only has this led to specialized ships such as container ships, but it has revolutionized port operation concepts: transportation by sea is at last becoming a truly integrated part of a world-wide cargo distribution system. 相似文献
7.
根据现有的快递运输突发现象会造成较大经济损失、配送环节带来的人力等各种资源浪费问题,结合树莓派和GPS导航技术,提出了一种基于GPS导航技术的智能无人快递车研究方案。该设计采用GPSM8N模块进行数据采集,以串口工作方式将数据传输至树莓派,然后对信号进行分结算处理实验后记录当前位置。通过计算的导航角调整小车向航点驶去,到达指定位置后,通过红外传感器检测到外部环境后打开自身所装配的货舱。设计通过自动导航实现了智能快递运输理念,方便多种场所使用,提高了人们的生活质量。 相似文献
8.
据不完全统计,全国铁路每年有超过10亿人/次的客运流量,铁路列车作为运输旅客的载体蕴藏着一个潜在的、亟待开发的巨大通信市场。开发这个市场,为旅客在出行途中提供商用级的电信服务,一直是铁道部领导重视以及中国铁通探讨和研究的课题。本文对无线公用电话在旅客列车上的成功应用进行了深入研究。 相似文献
9.
A panel convened by the U. S. Department of Commerce Technical Advisory Board in 1966 was asked to survey the technical feasibility of novel modes of high-speed ground transportation (HSGT) systems and recommend research programs necessary for the development of such systems. HSGT systems, for the purpose of the study, were defined as operating in, or on, fixed guideways at intercity cruising speeds of at least 300 mi/h (482.8 km/h). Although present knowledge of the nation's total future transportation requirements, and of the relative role of HSGT, was judged to be insufficient for a decision to construct such a system, the panel considered the creation of an HSGT system to be technically attainable and recommended a multifaceted research and development program. Specific research areas recommended were those needed to provide data necessary to a decision to construct an HSGT system and to select from among alternative system concepts. Highest priorities were assigned to system simulations and transportation data studies, resolution of the contact versus fluid support question, experimental studies of the aerodynamics of vehicles traveling it tubes at high speeds, development of new tunneling technology, and transfer of electrical energy by contact rails and collectors at HSGT speeds. 相似文献
10.
In recent years,the demand for urban express delivery experiences fast growing.Several startup delivery corporations,such as iShansong,have provided the delivery services,which are promised to deliver a parcel within 1 or 3 hours in a city.However,since the quality of the promised services have not been fully quantitatively analyzed based on real data,it is quite often that couriers refuse to pick up delivery requests or the accepted parcels fail to be delivered on time.To address the above issue,a metro crowd-delivery system was proposed,which could utilize the historical records of metro passengers to analyze the quality of the delivery service and provide differential service within different period of time.The system not only meet the requirements of high delay requirements of the courier,but also as a city-wide express supplement.At the same time,a courier transit program was proposed.Experiments show that this transfer program is efficient. 相似文献
11.
Ming Zhu Xiao-Yang Liu Meikang Qiu Ruimin Shen Wei Shu Min-You Wu 《Mobile Networks and Applications》2016,21(5):890-900
The increasing population in urban areas gives rise to a huge traffic pressure. A cloud-based industrial system, public vehicle (PV) system, is promising to mitigate the traffic congestion in smart cities, where passengers can share PVs and transfer among them with scheduling decisions made by the cloud. This paper studies the transfer problem in the PV system due to that transfer can improve the whole traffic efficiency with sacrificing a little comfort with the corporation of all the PVs. The transfer problem is NP-Complete through our analysis. Our work can be separated into three steps. First, we introduce several factors to guarantee the comfort of passengers during transfer. Second, we propose two algorithms through the graph-based scheduling problem aiming at reducing the travel distance of all the PVs with service guarantee. Third, simulations based on the Shanghai (China) urban road network show that, the total travel distance of PVs is reduced under the quality of service for passengers, and the traffic efficiency is improved. 相似文献
12.
随着城市轨道交通网络规模的扩大,城市轨道将逐渐成为输送城市客流的主要交通方式,城市轨道交通的安全保障和应急处置能力也越来越重要。从城市轨道交通应急指挥中心功能需求分析出发,深入研究了城市轨道交通应急指挥中心的综合信息应用系统,并提出所需的关键支撑系统,以期能够系统性地分析和总结城市轨道交通应急指挥中心的业务功能,供相关城市在建设轨道交通应急指挥中心时进行参考。 相似文献
13.
乘客信息系统是一个集地铁运营信息服务、多媒体实时资讯发布、广播电视节目制作与播出、地铁视频监控、地铁设备监控于一体的综合服务平台.如何从技术上保证乘客信息系统的稳定运营,成为运营方实际的需求,也是车载系统设计者新的课题.基于多年的运营经验和多年的乘客信息系统设计成果,提出了一种乘客信息系统设计架构,保证系统稳定的同时,为乘客出行提供便利和服务. 相似文献
14.
射频识别技术及其在交通领域的应用 总被引:20,自引:3,他引:20
射频识别(RFID)技术采用大规模集成电路技术,识别技术,计算机及通信技术,通过读写器和安装在载体(车辆或设备或人员)上的RFID卡,构成RFID系统,实现对载体的非接触的识别和数据信息交换,RFID技术已广泛应用于交通、公安,路政、物流管理等领域,本文介绍该技术在交通领域的几个主要应用。 相似文献
15.
针对港口货船的焦炭称量问题,设计基于Visual Basic6.0的港口运料系统。上位机通过RS 232串口发出控制命令,控制下位机(散料秤)称量货物,再把数据实时返回到上位机,实现上位机和下位机的实时通信和上位机对下位机的控制。为了使得系统在工业控制应用中的功能更加完善,上位机还具备访问数据库、实时更新数据库以及打印报表等功能。 相似文献
16.
天线双随动系统跟踪非合作目标时,需要外部搜索雷达的配合来提供非合作目标的位置坐标。为了保证天线跟踪系统的可靠跟踪,在两测站交会的基础上提出了多测站数据交会的方法,并对多测站交会数据采用了平滑滤波处理、预估插值处理等实时数据处理方法,从而保证了交会引导的精确性。最后给出了多站测量数据自动交会的软件实现流程图。该方法已在工程实践中获得应用,取得良好的效果。 相似文献
17.
交流特高压电力输送是电力输送的重要组成部分,交流特高压现场的交接中会出现局部电力交接中出现电力输送空间电力干扰问题,结合现代电力运输中多种电力检测系统,实现了交流特高压现场交接关键技术的科学性连接,结合电力应用实际,对其应用的关键实验技术进行分析. 相似文献
18.
Mobile Hotspot Network System for High‐Speed Railway Communications Using Millimeter Waves
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We propose a millimeter wave (MMW)‐based mobile hotspot network (MHN) system for application in high‐speed railways that is capable of supporting a peak backhaul link throughput of 1 Gbps per train at 400 km/h. The MHN system can be implemented in subways and high‐speed trains to support passengers with smart devices and provide access to the Internet. The proposed system can overcome the inherent high path loss in MMW through system designs and high antenna gains. We present a simulation of the system performance that shows that a fixed beamforming strategy can provide high signal‐to‐interference‐plus‐noise‐ratio similar to those of an adaptive beamforming strategy, with the exception of 15% of the train path in which the network can use link adaptation with low‐order modulation formats or trigger a handover to maintain the connection. We also demonstrate the feasibility of the MHN system using a test bed deployed in Seoul subway line 8. The backhaul link throughput varies instantaneously between 200 Mbps and 500 Mbps depending on the SNR variations while the train is running. During the field trial, the smartphones used could make connections through offloading. 相似文献
19.
Karols P. Dostert K. Griepentrog G. Huettinger S. 《Selected Areas in Communications, IEEE Journal on》2006,24(7):1339-1350
The rapid progress of power line communications (PLC) for data transmission over electric power supply systems is now opening ways for special applications such as train automation in local transportation and mass transit (MT) systems. These DC-powered traction networks can be used as communication links between wayside equipment and the moving trains. As MT networks significantly differ from usual electricity supply systems, the usage of existing models and communication equipment for conventional PLC channels turns out infeasible. Therefore, the work reported in this paper focuses on MT channel investigation and modeling, in order to develop novel adapted solutions. The outcome is a stochastic MT channel model, which-besides multipath and time-variance-also includes peculiar properties such as the behavior of ring structures and the impact of the Doppler effect invoked by moving trains. In addition, a very special interference scenario is treated, caused by the rectifiers in these DC-powered environments. Besides a complete simulation model, this paper presents detailed guidelines for building emulation hardware, so that channel adapted PLC system design for MT networks can now be successfully started without further expensive field trials. 相似文献
20.
基于BP网络的交通运输能力预测 总被引:3,自引:2,他引:1
杨居义 《微电子学与计算机》2008,25(9)
交通运输能力预测是货运需求和经济发展关系研究中的一个重要问题,对货运量的预测研究和分析具有实际意义.在分析了货运量影响因素和预测特点的基础上,利用BP神经网络对货运量进行了预测.网络的输出和仿真结果证明了网络的有效性. 相似文献