基于公交智能调度系统的公交换乘算法实现

通过对城市居民公交出行选择影响因素和选择逻辑的分析,利用地理信息系统（GIS）技术构建公交换乘数据模型和公交智能调度系统数据计算出行时间,以此为基础实现以最少换乘次数为第一目标,出行时间最短为第二目标的公交换乘算法。该算法考虑了步行换乘、行驶时间、换乘时间及公交线路上、下行因素对换乘查询的影响,能够较快地提供公交换乘方案。     

温拌沥青混合料马歇尔变温变击实功设计方法

为了建立温拌沥青混合料组成设计方法,在不同温度和击实次数下进行了AC-13C温拌沥青混合料的马歇尔击实试验,分析了温拌沥青混合料体积特性。分析结果表明：随着击实温度的降低和击实次数的减少,温拌沥青混合料的空隙率和矿料间隙率增大,沥青饱和度降低;与热拌沥青混合料相比,温拌沥青混合料中沥青被集料吸收的含量（质量分数）、有效...     

桩端后压浆技术在京哈高速公路改扩建工程中的应用

在京哈高速公路长春至四平段改扩建工程建设项目中,为有效控制新旧桥梁之间的沉降差,拼宽桥梁钻孔灌注桩基础采用桩端后压浆技术.阐述了桩端后压浆的施工工艺控制措施、施工控制要点、工艺流程等,总结了桩端后压浆技术的特点.     

基于大样本密度快速测定在路面施工压实质量控制中的研究

无核密度仪广泛应用于高速公路沥青路面施工质量控制中,结合汕湛高速公路T22标中面层试验路施工,分析了第三代PQI380检测的工作原理和标定方法,并进行了PQI法与钻芯法的对比,验证了PQI法的测量精度。据此采用PQI对中面层GAC-20C试验路施工过程压实质量控制,通过碾压次数与实测密度之间的曲线关系,得出本次中面层施工碾压次数不宜超过4次。以及基于PQI测得的施工后大样本密度数据,分别利用数理统计和灰度图的方法评价路面施工均匀性质量,确定薄弱区域和成因分析,为后续改善施工工艺和机械设备以及采取补救措施提供依据。     

基于事故树分析法(FTA)的客运专线特殊线路所安全风险分析

随着客运专线运营里程的不断增加,各线间的互联互通越来越多,为了地区疏解等原因而设立的线路所也日益增多,其中由于种种原因而不能设立隔开设备的线路所也随之增多,对这种特殊线路所存在的运行风险评估就尤为重要迫切。利用FTA(事故树分析法)对特殊线路所安全风险进行定性分析,并找出了风险防控的措施。     

企业组织管理理论系统分析

本文在研究组织理论产生与发展的基础上,对组织模型与结构理论、组织程序设计等进行了系统分析。     

文学本质和现代转型

“五四”新文学所开启的文学的现代转型成为一个众说纷纭的话题，文章试图从文学本质的角度，重新梳理现代转型之于文学现代性追求的作用以及对当下文学的启示意义。     

Experienced travel time prediction for congested freeways

Travel time is an important performance measure for transportation systems, and dissemination of travel time information can help travelers make reliable travel decisions such as route choice or departure time. Since the traffic data collected in real time reflects the past or current conditions on the roadway, a predictive travel time methodology should be used to obtain the information to be disseminated. However, an important part of the literature either uses instantaneous travel time assumption, and sums the travel time of roadway segments at the starting time of the trip, or uses statistical forecasting algorithms to predict the future travel time. This study benefits from the available traffic flow fundamentals (e.g. shockwave analysis and bottleneck identification), and makes use of both historical and real time traffic information to provide travel time prediction. The methodological framework of this approach sequentially includes a bottleneck identification algorithm, clustering of traffic data in traffic regimes with similar characteristics, development of stochastic congestion maps for clustered data and an online congestion search algorithm, which combines historical data analysis and real-time data to predict experienced travel times at the starting time of the trip. The experimental results based on the loop detector data on Californian freeways indicate that the proposed method provides promising travel time predictions under varying traffic conditions.     

Door-to-door travel times in RP departure time choice models: An approximation method using GPS data

A common way to determine values of travel time and schedule delay is to estimate departure time choice models, using stated preference (SP) or revealed preference (RP) data. The latter are used less frequently, mainly because of the difficulties to collect the data required for the model estimation. One main requirement is knowledge of the (expected) travel times for both chosen and unchosen departure time alternatives. As the availability of such data is limited, most RP-based scheduling models only take into account travel times on trip segments rather than door-to-door travel times, or use very rough measures of door-to-door travel times. We show that ignoring the temporal and spatial variation of travel times, and, in particular, the correlation of travel times across links may lead to biased estimates of the value of time (VOT). To approximate door-to-door travel times for which no complete measurement is possible, we develop a method that relates travel times on links with continuous speed measurements to travel times on links where relatively infrequent GPS-based speed measurements are available. We use geographically weighted regression to estimate the location-specific relation between the speeds on these two types of links, which is then used for travel time prediction at different locations, days, and times of the day. This method is not only useful for the approximation of door-to-door travel times in departure time choice models, but is generally relevant for predicting travel times in situations where continuous speed measurements can be enriched with GPS data.     

Book reviews

THE SEVENTH AUSTRALIAN TRANSPORT RESEARCH FORUM, by K. W. Ogden.

AIRLINE PLANNING: CORPORATE, FINANCIAL AND MARKETING by Nawal K. Taneja. Lexington, Mass., Lexington Books, 1982. 207 pp. (£19.50)

SOLVING LOCAL GOVERNMENT PROBLEMS: PRACTICAL APPLICATIONS OF OPERATIONS RESEARCH IN CITIES AND REGIONS, by Charles E. Pinkus and Anne Dixson. George Allen and Unwin, London, 1981. (Hardback £20.00; paperback £8.95)

SCIENTIFIC MANAGEMENT OF TRANSPORT SYSTEMS, edited by N. K. Jaismal. Published by North‐Holland Publishing Company (U.S. $58.50)

TRANSPORTATION AND TRAFFIC ENGINEERING HANDBOOK (Second Edition), edited by W. S. Homburger, Englewood Cliffs, N.J., 1982. Prentice Hall, pp. 883.

ECONOMICS OF PUBLIC TRANSPORT, by C. A. Nash. Longman, London, pp. 194. (£6.95).