Integrated models of land use and transportation for the autonomous vehicle revolution

ABSTRACT

The advent of the autonomous vehicle (AV) will affect not only the transportation system, but also future patterns of land development. Integrated land use and transportation models will be critical tools in assessing the path forward with this technology. Key questions with respect to land use impacts of AVs arise from potential changes in sensitivity to travel and reduced demand for parking. It is an open question whether AVs will induce urban sprawl, or whether spatial economies of agglomeration will mitigate any reductions in travel time sensitivity. The deployment of shared fleets of AVs would likely reduce parking demand, producing yet to be explored impacts on property development within existing urban footprints. We perform a critical assessment of currently operational models and their ability to represent the adoption of AVs. We identify the representation of time in such models as a vital component requiring additional development to model this new technology. Existing model applications have focused on the discrete addition of new infrastructure or policy at a fixed point in time, whereas AV adoption will occur incrementally through time. Stated adaptation surveys are recommended as tools to quantify preferences and develop relevant model inputs. It is argued that existing models that assume comparatively static equilibrium have been convenient in the past, but are insufficient to model technology adoption. In contrast, dynamic model frameworks lack sufficient structure to maintain reasonability under large perturbations from base conditions. The ongoing advancement of computing has allowed models to move away from being mechanistic aggregate tools, towards behaviourally rich depictions of individual persons and firms. However, much work remains to move from projections of existing conditions into the future, to the evolution of the spatial economy as it evolves through time in response to new technologies and exogenous stresses. Principles from complex and evolutionary systems theory will be important in the development of models with the capacity to consider such dynamics.     

Online channel strategies under different offline channel power structures for the Belt and Road of China

ABSTRACT

This paper explores the online channel strategies adopted by Chinese manufacturers with regard to the Belt and Road. It also investigates the effect of offline channel power structures and maritime transportation costs on online channel mode selection and pricing strategies. The offline channel power structures are classified into three types, namely, Chinese manufacturer Stackelberg (MS) structure, vertical Nash (VN) structure, and foreign retailer Stackelberg (RS) structure. Furthermore, a game model is developed among the Chinese manufacturer, foreign retailer, and cross-border e-tailer to investigate the interactions among offline channel power structures, maritime transportation costs, and Chinese manufacturers’ online channel mode selection. The results show that Chinese manufacturers’ preferences for the online agency selling mode increases correspondingly with the decrease in their market position and bargaining power. Moreover, foreign retailers can obtain higher profits in the online agency selling mode under the VN structure. However, the level of profit for foreign retailers depends on the intensity of their competition with cross-border e-tailers under the MS and RS structures. Finally, consumers in countries along the Belt and Road can obtain a higher surplus in the online agency selling mode under all of the structures.     

基于B/S结构的机车售后服务管理系统

文章简述了ActiveX组件模型结合ASP技术在Internet环境下实现基于Browser/Server结构的机车售后服务管理系统。该系统在ActiveX技术基础上通过ADO编程实现数据传输和访问,结合ASP和ActiveX控件技术实现动态发布和在线管理。     

优化运输结构加快铁路发展

交通运输业的发展受资源环境约束,各种运输方式在资源消耗和环境保护等方面存在较大差异,对资源和环境的影响也不同。我国各种运输方式发展的关键是在资源环境约束条件下协调发展。深入贯彻落实科学发展观,加强统筹协调和宏观调控,推进交通运输结构优化,加快铁路发展,提高铁路运输能力,促进节能减排、资源节约型和环境友好型社会建设。     

70 m跨二铰型上承式桁架混凝土拱桥的施工技术

介绍70 m双铰型上承式桁架拱桥的施工和在施工阶段监测监控的内容及方法,可供类似工程建设参考。     

机车用AC 3 kV真空接触器的设计

基于一般工业用真空接触器的总体布置形式和传动方式，根据机车用真空接触器的结构特点，对机车用ＡＣ３ｋＶ真空接触器的设计原则及设计中的一些问题作了介绍。     

两用型铁水车研制

介绍了两用型铁水车的技术参数、结构特点及其应用情况。     

焊接钢结构现场施工质量与工艺控制

针对焊接钢结构现场施工过程中,以大运高速公路康庄服务区大型加油广场的钢结构施工为实例采取的一些新技术措施等进行阐述和总结。     

BITBUS结构及其在电气化复线渡线开关监控系统中的应用

本文提出在电气化铁路远动系统中采用高性能，低价格，灵活易用的通讯网络ＢＩＴＢＵＳ构成分层的分布式网络系统，用网络结构代替常规的双机加切换器的结构。既简化了系统结构了又成功地解决了系统资源的共与分配，并为系统以后可能的扩展与联网打下了基础。运用软件工程学的有关技术和方法开发系统软件，使系统结构清晰，易于维护和扩充，本文针对电气化复线渡线开关监控系统的特点，给出了该系统采用的软，硬件方案及其实现过程。