基于联合模型的机场航站楼寻路影响因素

为解决旅客感知对机场航站楼寻路影响缺乏定量描述的问题,使用个人素质能力、感知信息有效性、感知设施布局分散程度这3个潜变量作为旅客在寻路过程中的感知影响变量。结合个人属性、出行特征、机场状况等变量,构建融合旅客感知影响的机场航站楼寻路SEM-Logit联合模型,并运用问卷调查数据进行实证分析。结果表明,感知因素潜变量对航站楼内的寻路过程具有重要影响作用。个人素质能力（0.107）、感知信息有效性（0.379）对寻路便捷程度具有正向影响,感知设施布局分散程度（-0.330）具有负向影响;旅客的年龄、性别也是影响航站楼寻路的关键因素。联合模型比基础回归模型考虑因素更全面、解释能力更强。     

基于多智能体建模和蒙特卡洛仿真的跑道容量评估

分析了飞机编队动力学特性以及机场组织模式、管制方式和飞行方式等特征,建立了跑道容量计算模型和跑道运行模型;以中距平行双跑道半混合运行模式和混合运行模式作为典型场景,综合运用多智能体建模和蒙特卡洛仿真方法,计算了不同运行模式下跑道容量;设计正交仿真试验,研究了跑道容量与运行模式、起降比例、出动间隔、机型比例、编队数量和环境因素的关系。仿真结果表明：相比于半混合运行模式,混合运行模式的起飞容量平均增加了55.2%,着陆容量平均减小了6.2%,总容量平均增加了28.5%;随着出动间隔从60 s增加到180 s,半混合运行模式的总容量减小了27.2%,混合运行模式的总容量减小了24.9%;随着机型比例从0增加到1.0,半混合运行模式的总容量减小了29.7%,混合运行模式的总容量减小了29.2%;随着平均编队数量从1.9增加到3.2,半混合运行模式下的总容量增加了9.8%,混合运行模式的总容量增加了7.1%。可见,混合运行模式的性能整体优于半混合运行模式,跑道容量与任务出动方式密切相关,需要根据任务出动方式合理选择跑道运行模式。     

沥青跑道抗滑性能分析

为了提高机场沥青跑道的抗滑性能, 保证飞机滑跑安全, 分析了沥青道面防滑性能要求, 研究了沥青道面摩擦系数、粗糙度、抗滑耐久性等防滑性能指标, 参照国际民航的规定和中国沥青道面抗滑标准, 提出了考虑飞机滑跑安全的道面技术参数, 并对材料性质、沥青混合料类型与级配、沥青用量等因素对抗滑性能的影响进行了分析。分析结果表明: 当沥青道面摩擦系数摆式仪测定值控制在45以上, 构造深度大于0.4 mm时, 飞机滑跑是安全的; 通过选择坚硬石料作为沥青混合料的集料, 采用沥青玛蹄脂碎石混合料作为面层材料, 设计合理的坡度, 及时清除道面积雪等设计与使用维护措施, 可增强沥青道面抗滑性能。     

机场混凝土道面封缝材料疲劳特性

为了提高机场道面的防水密封效果, 对道面封缝材料的受力性能进行了疲劳特性试验, 分别考虑了接缝宽度、拉伸压缩和冻融对封缝材料疲劳特性的影响。在试验中封缝材料同时受到拉伸(压缩) 和剪切的作用, 并模拟了材料在胀缝和横向缩缝中的受力情况。经50次冻融循环处理后的材料较未经处理的材料破坏加载次数小, 应力状态均有较大降低, 最大值达78%, 聚硫密封胶相对于聚氨酯密封胶有较好的疲劳性能, 在温差较大的机场建议采用聚硫密封胶。     

基于深度图像的机场道面裂缝自动检测算法

为了实现强噪声、弱光照、低对比度条件下的机场道面细小裂缝检测, 设计了基于深度图像的机场道面裂缝检测算法; 将采集到的深度图像划分成多个网格, 并对每个网格进行扩充, 获得了局部道面区域; 针对每个网格区域, 基于随机抽样一致算法进行局部三次曲面构建和优化估计; 在此基础上, 在全局尺度下融合全部网格区域的曲面模型, 生成整个图像采集区域道面的全局曲面模型; 利用全局曲面模型与原始深度图像之间的差值图像, 采用自适应阈值方法分割出候选裂缝像素, 并利用裂缝的像素总数、长度以及长宽比等多种形态学约束筛选候选裂缝像素, 去除错误的候选裂缝像素, 从而获得了最终的裂缝检测结果; 在机场道面深度图像数据集上进行了试验, 以人工标注结果作为真实值, 以准确率、召回率以及F值作为量化评估指标, 将提出的算法分别与4种有代表性的传统算法进行了对比。试验结果表明: 传统算法能够取得的最高准确率、召回率以及F值分别为77.05%、41.02%和50.02%, 提出的算法在准确率、召回率和F值3个指标上均有明显优势, 其均值分别为91.20%、97.99%和94.12%;提出的算法能够在分辨率为1 984像素×2 000像素的深度图像上检测出最小宽度为3 mm、最小长度为10 cm的裂缝, 实现了在复杂机场道面场景中识别细小裂缝的目标。     

基于多普勒测距雷达的实时距离测量系统

研究了机场助航灯光强动态检测技术的工作原理, 分析了光强动态检测中距离测量的特点, 基于多普勒测距雷达原理, 构建了非接触式实时距离测量系统。结合硬件板卡, 采用面向对象方法设计了测量软件, 使用多线程技术, 使距离测量和灯光照度测量在不同的线程中工作, 并对整个光强动态测量过程进行自动控制。试验结果表明: 应用该系统实现了距离测量和灯光照度测量的同步进行, 距离测量误差低于5 mm; 通过距离测量能够对光强动态测量过程进行精确控制, 照度测量点间距控制精度达到0.000 5%。可见, 该系统实时性好, 测量精度高, 能够满足实时进行精确距离测量的要求。     

Effects of high-speed rail and airline cooperation under hub airport capacity constraint

This paper analyzes the effects of cooperation between a hub-and-spoke airline and a high-speed rail (HSR) operator when the hub airport may be capacity-constrained. We find that such cooperation reduces traffic in markets where prior modal competition occurs, but may increase traffic in other markets of the network. The cooperation improves welfare, independent of whether or not the hub capacity is constrained, as long as the modal substitutability in the overlapping markets is low. However, if the modal substitutability is high, then hub capacity plays an important role in assessing the welfare impact: If the hub airports are significantly capacity-constrained, the cooperation improves welfare; otherwise, it is likely welfare reducing. Through simulations we further study the welfare effects of modal asymmetries in the demands and costs, heterogeneous passenger types, and economies of traffic density. Our analysis shows that the economies of traffic density alone cannot justify airline–HSR cooperation.     

Knowledge based decision support in airport terminal design

The state of the art in airport terminal design has essentially remained unchanged since the 1970s, relying on the use of detailed simulation together with empirical and statistical formulae for sizing the terminal. Air transport has altered considerably since then, with increased use of air travel for both business and leisure, together with the increased use of ‘hub’ terminals in which the terminal acts as an interchange stop on a journey involving several flights. The use of simulation involves a detailed analysis of the terminal design under one set of conditions. To change the design or operating conditions involves a complete resimulation using the new design parameters which is time consuming and computationally expensive.

By using a knowledge based approach, a system can be provided which has the flexibility and speed required to explore the consequences of implementing design decisions in a variety of conditions, together with the ability to use and alter facility sizing methodologies to reflect current and future design guidelines.     

Capacity investment model for airport facilities under demand uncertainty

This paper addresses strategic airport facility planning under demand uncertainty. Existing studies are improved by (1) allowing capacity contraction and (2) adopting more flexible delay functions. A mixed‐integer nonlinear program, which incorporates scale economies in construction, time value of money, nonlinear congestion effect, and other factors, is proposed for optimizing the capacity expansion/contraction decisions over time for multiple airport components. The stochastic problem is converted into its deterministic equivalent because the number of demand scenarios considered is finite. A discrete approximation technique is used to remove the nonlinearities. Numerical studies are presented to demonstrate the capability of the proposed model and the computational efficiency of the solution method. The “Flaw of Averages” due to faulty decisions based on the average future condition is illustrated, and trade‐offs among various costs are discussed in the numerical analyses. Copyright © 2016 John Wiley & Sons, Ltd.     

西安机场城际线列车因移动授权超时而引发紧急制动故障的分析

西安机场城际线路信号系统采用基于通信的列车控制(CBTC)系统.列车在单A网、单B网模式测试期间,曾多次出现由移动授权超时导致的紧急制动故障.经分析列车运行数据,提出测试方案,并对测试结果进行综合分析,采取了优化LTE(长期演进)区间网络、调整车载信号设备参数、升级相应软件等措施顺利地解决了因移动授权超时而引发的故障.