The impacts of changing flight demands and throughput performance on airport delays through the Great Recession

Several significant events between 2007 and 2009 impacted flight demands and the abilities of the three major New York area airports to handle demand. This paper assesses the results of applying a probabilistic simulation method – which isolates the individual contributions of changes in flight demand and changes in airport throughput performance to changes in flight delays – to diagnose how these different events may have caused operational changes at these airports, and in turn, how the results may be used to inform policies for appropriate countermeasures. The analysis revealed two key observations. Firstly, certain patterns in throughput performance shifts caused the most significant delays, and were more likely to have been caused by controller staffing issues rather than caps. Secondly, relatively constant average delays from one year to the next may result from significant demand drops accompanied by large throughput performance degradations at an airport. This suggests that not only operational limitations on capacity encourage airlines to reduce schedules, but that changed demands can also impact throughput performance. Overall, the analysis indicates that caps may not have provided their fully intended delay benefits. Although they successfully reduced overall flight demands at LGA and JFK, they also directly limited throughput performance at critical times, in turn limiting delay benefits. In addition, demands at the busiest times of the day appear to be relatively inelastic to these operational limitations, insofar as demand profiles at EWR and JFK remained “peaky” in 2008 and 2009. Also, the recession was largely responsible for reducing demands at the airports in 2009, but the delay benefits of this were dampened by a corresponding throughput performance degradation. Based on the above observations, a more direct demand management policy combined with policies that focus on maintaining high staffing capabilities at critical times of the day may be considered, to reduce the likelihood of major queue formation on days that do experience sustained demands. The results also suggest that a more flexible caps system, particularly during times of heavy queues, could be explored. Although airport practitioners have keen understandings of how their airports operate, without the support of quantitative analysis tools, it can be more difficult to argue the need for appropriate countermeasures. An analysis such as the one presented here can provide the detailed quantitative substantiation required to build cases for these targeted policy directives and infrastructure investments.     

墩台施工监理中的若干问题

针对工程的特殊性 ,管理人员在质量控制方面及相关协调工作方面进行了必要的调整和大胆尝试 ,最终促成该项目的圆满完成。     

建设工程监理企业的业务拓展与发展对策

在分析现阶段建设工程监理企业如何开展监理业务的基础上,对今后建设工程监理企业的业务拓展方向问题进行探讨,提出了南单纯的建设监理向综合型项目管理业务发展的战略,及监理企业业务拓展的方式与对策.     

系统效能通用评估工具研究

基于数据库和算法集成,设计了一套具有良好通用性、灵活性、可扩展性的系统效能评估工具,并以此工具为基础,针对不同的评估需求、数据量和应用环境提出对应的解决方案.     

扶植菲迪克条款的原则在高速公路建设监理中健康成长

结合多年监理工作的实践体会介绍了菲迪克条款的核心与国情，省情的适合程度以及监理的作用．并提出监理如何才能健康发展。     

建设工程监理企业人员素质现状研究

文章以江苏省南通市监理行业知识竞赛为案例,对当前建设工程监理人员的素质现状进行了分析研究,并针对建设工程监理专业人才的素质提高和人才培养提出了见解。     

关于创新服务理念建设服务型海事的思考

建设服务型海事是深入贯彻落实交通部党组提出的“三个服务”理念的体现，也是海事发展的客观要求。文章提出加快海事职能转型是建设服务型海事的关键，并就如何创新服务理念、建设服务型海事作了探讨。     

体现“湖北制造”经济特色的数控技术专业共享型教学资源库建设

探讨了立足"湖北制造"区域经济特色,依托先进资源管理平台,构建共享、开放型数控技术专业资源库的目标、思路、内容、步骤、规格等核心问题。提出了涵盖2个专业方向、针对15门核心课程、兼顾3个学习层次、打造7个特色模块,建设8种类型资源包、设计多种表现形式的资源库建设方案,以此推动专业建设和课程建设,满足教与学不同方面、多种层次的需求。     

V型墩连续刚构桥施工监控分析

佛山南庄二桥是V型墩连续刚构桥，梁体采用移动支架悬臂施工，均为动态成形，高空作业，故该桥的施工控制成为保证桥梁施工质量的关键因素。文章介绍了该桥施工监控的控制思路和现场测点布置、测量的内容，重点阐述了结构线形控制的实施过程，为同类桥梁的施工控制提供参考依据。     

中小型车站Smart2.0系统的方案与安全性分析

作者介绍了适合中小型车站Smart 2.0系统的一种可行方案,通过对该系统安全性的分析,该方案具有结构简单、安全可靠、节约投资等特点。