LED照明智能调光技术在公路隧道工程中的应用

隧道照明成了公路运营单位的沉重经济负担。而为节约隧道照明费用,减少电费支出,国内部分隧道,出现了运营管理部门关闭部分隧道灯,或关闭一侧灯光的现象,严重影响安全行车。如何解决安全行车与节约能源之间的矛盾,达到"安全行车与高效节能的完美结合",是摆在当前隧道管理者、建设者、运营者面前一项急需解决的重大任务。     

新七道梁公路隧道运营通风效果测试及分析

文章通过对新七道梁公路隧道内外气温、风速等气象条件的现场测试,研究了在隧道区域范围内风速和气温等因素影响下,隧道内风速及洞内气温变化规律,可为新七道梁公路隧道营运过程中的通风控制,以及西北中高海拔地区公路隧道通风、消防、救援研究提供依据。     

A new approach for improving the performance of freight train timetabling of a single-track railway system

A new approach for improving the performance of freight train timetabling for single-track railways is proposed. Using the idea of a fixed-block signaling system, we develop a matrix representation to express the occupation of inter- and intra-station tracks by trains illustrating the train blocking time diagram in its entirety. Train departure times, dwell times, and unnecessary stopping are adjusted to reduce average train travel time and single train travel time. Conflicts between successive stations and within stations are identified and solved. A fuzzy logic system is further used to adjust the range of train departure times and checks are made to determine whether dwell times and time intervals can be adjusted for passenger and freight trains at congested stations to minimize train waiting times. By combining manual scheduling expertise with the fuzzy inference method, timetable efficiency is significantly improved and becomes more flexible.     

公路及隧道自发光节能照明标识设置工程

<正>编者金华市公路、隧道自发光节能照明标识设置工程,是浙江省交通运输厅重点科研成果推广应用项目。2011年由金华市公路部门在全市251公里农村公路和10个公路隧道组织实施。工程自2011年9月开始,当年12月全面完成,总投资554万元。该工程利用吸储自然光能后主动发光的新材料、新技术解决了当地农村公路夜间照明诱导问题,改变了以往公路临水、临崖危险路段护栏、桥梁、短隧道等安保设施必     

Design and efficiency measurement of cooperative driver assistance system based on wireless communication devices

In this paper, we participate to the effort of investigating the use of the inter-vehicle communication in order to increase safety on the roads. In order to fill the gap between the standardization work and the proposed services, our work aims at designing cooperative applications using an existent wireless technology. In this paper, we describe the communication architecture deployed on board our fleet of intelligent vehicles and based on 802.11 g+ devices. Using this architecture, we will prove the feasibility of cooperative services. Thus, we choose to study two situations of conflict on roads: crossroads approaching and lane changing manœuvre. For both scenarios, we analyze the contribution of our system for risk assessment and collision avoidance.     

高压钠灯和LED灯在隧道照明中的应用分析

为了探究高压钠灯和LED灯组合照明在隧道照明中的适用性,文章系统梳理了国内外隧道工程照明领域中高压钠灯和LED灯的发展现状、存在的问题及对策及发展前景。目前单独使用LED灯具确实能达到节能减排、低碳环保的效果,但却亮度不足,而考虑到传统隧道照明采用高压钠灯的方案费用高以及单一光源对隧道入口段产生的影响,故将LED灯和高压钠灯组合使用,以发挥两种光源的优点。本文通过文献查阅和调研最终得出在目前高压钠灯向LED灯过渡的发展阶段,组合照明的方式在隧道入口段可以提高可视性,充分发挥两种灯具的优点。     

A new scenario based approach for designing driver support systems applied to the design of a lane change support system

Designing a new driver support system that meets the expectations of drivers is a difficult and time-consuming process. Despite the availability of various types of design support, it has essentially remained a process in which designers are forced to make assumptions about what other people want. This paper presents a new approach for determining users’ preferences and finding the best compromise between those preferences when designing a new driver support system. Using scenarios, virtual reality simulation, and gaming principles, the new approach gives users a pro-active role in the design process. To evaluate the new approach, it was applied to the design of a lane change support system. This resulted in a hierarchy of information that is a detailed, consistent and reliable image of users’ preferences. By combining this hierarchy with a manufacturing and marketing constraint, the design specification of a lane change support system was deduced. One of the many findings was that a lane change support system should be modular and that modules for the left side should be different from modules for the right side of the vehicle. The paper concludes with reasoning why the new approach offers added value for the design of driver support systems.     

A segregated urban busway system

A transport system has been proposed using buses operating over ordinary roads and over special reserved tracks (busways) on which they might be automatically guided. Using cost and performance data resulting from an earlier technical study (not reported here), a hypothetical network of routes and services in the West Midlands conurbation is studied. Estimates of patronage diverted from public and private transport enable the profitability of the system and its costs and benefits to be assessed. It is concluded that the system could be attractive both in commercial and in cost/benefit terms, providing acceptable means could be found for handling the buses around and through the inner central areas of cities. The net environmental changes, which would result from additional fixed plant permitting more efficient use of mobile plant, have not been quantified.     

船舶燃油系统使用低硫油的应对新措施

随着全球环境保护需求的不断提高,使得有关船舶硫化物排放的国际标准日益严格,从而导致船用低硫柴油的应用量正在逐渐增加。然而,目前大多数柴油机和燃油系统是针对传统燃油而设计的,由于低硫油的特殊性质,在使用低硫燃油过程中必然会产生一些问题。本文就低硫油的性质总结出了最新应对措施,确保了船舶的安全营运。     

A behavioural approach to the measurement of motorway circulation comfort and safety

The paper presents a method for measuring motorway circulation comfort and safety, based on the determination of the risk and stress levels characterizing the various choices made by drivers on the road. The method was worked out by analysing the distributions of the angular speeds with which the eye of each driver subtends the preceding vehicle width. The data used were taken from 155,000 vehicle passages over two sections of two-lane, divided carriageway motorways of identical geometric characteristics. The analysis suggested that the drivers passing over a motorway section can find themselves in three different states, which we shall term A, B and C, each having its own domain of driving alternatives. State A includes those drivers whose behaviour is not influenced by other vehicles present on the carriageway; state B encompasses those drivers whose behaviour is not influenced by the vehicles preceding them on the same lane, but by those that are following them; state C comprises those whose behaviour is affected by the vehicle preceding them on the same lane. Drivers in state C can be further divided into two groups: those, called C1, who accept the speed of the preceding vehicle and place themselves at a distance from him sufficiently large not to perceive the random fluctaution of relative speed and those, called C2, who do not accept the preceding vehicle speed and, waiting to overtake, approach him at a distance well below that of the C1 drivers so as to prevent the insertion of any changing lane vehicle and, contemporaneously, making their presence felt to the preceding vehicle. Drivers C2 because of the relative speed fluctuations receive a sequence of stimuli to which they react, also unconsciously, with a sequence of accelerations and decelerations. In this way their type of driving is risky and stressing. The authors propose the proportion s of all the drivers not in state C2 to be used as a measure of comfort and safety. The paper discusses and demonstrates how the proportion of drivers in the different states can be estimated; it also investigates the relationship existing between the measure s and the flow rate Q for various flow and time of day conditions. Furthermore the quality of circulation measure ξ₁ defined by the same authors in a preceding paper is shown to be strongly correlated with s.     

A queueing system for airport buses

The use of remote terminals to relieve airport congestion leads rather naturally to queueing systems with batch arrivals occuring at fixed time intervals to a multiple server service facility. In this paper arrival point steady-state solutions to the D^[X]/M/c queueing system are presented. Solution of the steady-state equation WP = W and Neuts' method of solving the GI^[X]/M/c system are used to obtain steady-state system size densities. Results obtained using the two methods are compared with each other as well as with simulation results.     

A GIS-Based traffic accident information system

This paper describes the process of developing a GIS-based traffic accident information system. A roadway network in Kent County, Delaware, was selected to demonstrate the graphic database. The development of the graphic and attribute databases on a workstation environment is described. Software was developed to graphically represent accident information pertaining to any point on the roadway network, and outputs for typical case scenarios are presented. The software also has the capability of displaying historical accident information pertaining to the site. This aspect would be helpful to the planner or designer in studying the impact of a particular roadway design with respect to safety. Some thoughts for future extensions of this study are also presented. Finally, it is concluded that a carefully designed GIS system can efficiently help transportation professionals with traffic safety studies and that its capabilities can be extended to include other areas such as pavement and inventory management, transit applications, and executive information systems.     

A measurement and Comparison of Cost Competitiveness of Container Ports in Southeast Asia

Terminal users face a variety of costs associated with the container terminal and those that are harder to quantify should not be ignored for they might represent a larger component of the overall costs associated with using a particular terminal. Similarly, the competitive advantage of a container terminal operator goes beyond the elements that can be quantified. The paper uses and modifies Cournot’s simultaneous quantity-setting model as a means to derive the overall costs of using the terminal. The application of this model to the perspective of competition between container terminal operators in Singapore, Port Klang and Tanjung Pelepas finds that the increasingly cost competitive operators in Port Klang and Tanjung Pelepas were able to close the gap with PSA Corporation in Singapore in the overall costs of using their terminal facilities between 1998 and 2002 although PSAC continued to enjoy a dominant share of the container-handling market in the region. The paper also highlights the tremendous amount of opportunities available to these terminal operators to advance and capitalise on their competitive advantages beyond aggressive price competition.The author would like to stress that the views presented do not represent those of his organization.     

中国外运:开启绿色物流新征程

在筹备旗下航运资产上市的同时,中国对外贸易运输(集团)总公司(简称"中国外运集团")还在加速拓展自己的物流板块,中国外运股份公司(简称"中国外运")还将与米其林的合作为契机,开启绿色物流新征程。     

A new approach for modeling of Fundamental Diagrams

According to the intra-vehicle interaction, a traffic flow can generally be divided into three homogeneous states (1) that of free driving, (2) that of bunched driving, and (3) that of standing. The parameter describing the state of free driving is the desired speed, for the state of bunching it is the intra-vehicle gaps (time headway) within the convoy and the mean speed of the convoy, and for the state of standing it is the maximum jam density. These are the most essential parameters which do not depend on the actual traffic situation.This paper introduces a new model which considers the Fundamental Diagram (equilibrium speed–flow–density relationship) as a function of the homogeneous states. All traffic situations in reality can be considered as combinations of the homogeneous states and therefore can be described by the essential parameters mentioned above. The non-congested (fluid) traffic is a combination (superposition) of the states of free driving and bunched driving, the congested (jam, stop, and go) traffic is a combination of the states of bunched driving (go) and standing (stop). The contribution of the traffic states within the differently congested traffic situations can then be easily obtained from the queuing and probability theory. As a result, Fundamental Diagram in all equilibrium traffic situations is derived as simple functions of the essential parameters.According to the new model the capacity of freeways and rural highways can be determined by measuring the essential parameters. This is much easier than measuring the capacity directly.Furthermore, the probabilities of the various traffic states can be obtained from the new model. This leads to new possibilities in real-time controlling and telematics.The new model is verified by comprehensive measurements carried out on freeways and rural highways in Germany.     

A hierarchical control system for freeway traffic

A hierarchical control system consisting of three control layers is developed for the freeway traffic control problem. A simplified optimization problem for the overall freeway system is solved on-line in an optimization layer. Optimization results are used as reference values for an inferior decentralized direct control layer. Prediction of slowly varying variables like on-ramp demands and origin-destination rates as well as of particular model parameters are provided by a supremal adaption layer. The overall control structure is shown to be robust even in the case of strong unexpected disturbances like incidents.     

A real-time system for monitoring driver fatigue

ABSTRACT

This paper presents a nonintrusive prototype computer vision system for real-time fatigue driving detection. First, we use Haar-like features to detect a driver’s face and conduct tracking by introducing an improved Camshift algorithm. Second, we propose a new eye-detection algorithm that combines the Adaboost algorithm with template matching to reduce computational costs and add an eye-validation process to increase the accuracy of the detection rate. Third, and different from other methods focusing on detecting eyes using the ‘bright pupil’ effect, which only works well only for certain constrained lighting conditions, our method detects and estimates the iris center in the hue (H) channel of the hue, saturation, value color space and fits the iris with an ellipse. After extracting the eye fatigue features, we calculate the PERCLOS measurement for fatigue evaluation. This system has been tested on the IMM Face Database, which contains more than 200 faces, and in a real-time test. The experimental results show that the system possesses good accuracy and robustness.     

新型临时路面系统在深圳地铁车站施工中的应用

针对深圳地铁科学馆站盖挖工程,介绍了一种新型的临时路面支撑系统--军用梁的设计与施工概况.实践表明,这种临时路面系统的应用是成功的,取得了较好的社会效益和经济效益,对类似工程具有重要的参考价值.     

The impact of a new rapid transit system on traffic on parallel highway facilities

This study analyzes data of traffic crossing San Francisco Bay and passing through the Berkeley Hills via Caldecott Tunnel to determine the effect of the opening in 1974 of the Bay Area Rapid Transit System (BART) transbay line. There was a sudden shift in trend lines in 1974; vehicle volumes dropped, transit patronage jumped, but total person trips in the short run followed roughly the trends of the previous eight years. Since 1974, the growth rate in person trips through the Berkeley Hills appears to have remained about the same, while transbay vehicle and transit traffic have increased at a more rapid rate. The increase in transit patronage is particularly noticeable between the morning and afternoon peaks and probably represents new trips by shoppers and sightseers. Whereas other factors, such as the increase in the price of gasoline between October 1973 and July 1974 may have contributed a little to the sudden change in the long‐range trends in 1974, it is believed that the major cause was the opening of the BART network to transbay travel.