Widening the Panama Canal and U.S. ports: historical and economic impact analyses

ABSTRACT

The economic history of the U.S. illustrates how the role of many cities has been changed by being seaports or located on navigable rivers or lakes. Based on the widening of the Panama Canal in 2016, the West Coast ports that include the west coast seaports of California, Oregon, and Washington were expected to become less important, while the freight shares of the East Coast and Gulf ports would increase. By how much it has been not easy to measure or predict so far, but this study attempted to define some of the key parameters in the measurement. As well as several relevant background topics, both the demand- and supply-side versions of the National Interstate Economic Model, have been applied for the measurement of economic impacts. U.S. port authorities and policy makers at the local and national levels who respond and develop plans for coping with the new realities of the Panama Canal are able to understand the extent to which changes in shippers’ and land-mode transporters’ behaviors would undermine the logistics and the costs of their activities. Therefore, this study is important for a diverse spectrum of port development strategies in the U.S. to respond to the Canal expansion.     

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南昌西站综合交通枢纽环境振动试验分析

现代大型综合交通枢纽综合了多种交通工具,实现了航空、高铁、普铁、轨道交通、公交和磁悬浮列车等多种交通方式的零换乘或短距离换乘。站房结构中包含高架桥梁、隧道和大跨度空间等复杂结构体系。由复杂结构形式而引发的环境振动,往往对人和精密仪器的使用造成极大的伤害。对南昌西站综合交通枢纽环境振动实测分析的结果表明,振动响应满足环境测评标准和舒适度要求。     

SPWM逆变技术在铁路信号电源的应用

介绍了SPWM逆变的概念和基本原理,简要分析SPWM逆变器的两个关键技术:死区补偿、谐波抑制。最后对SPWM逆变技术在铁路信号电源系统的应用进行探讨,对提高铁路信号电源质量,保证铁路运输安全有着较高的现实意义。     

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高墩大箱室梁墩顶0号段托架的设计与施工技术

介绍了高墩大箱室箱梁墩顶0号段悬托架的设计与施工方法,通过直接在墩身预埋牛腿,在牛腿上安放工字钢大梁和贝雷架分配梁以作为托架支撑,经计算后满足施工需要,从而优化施工方案。     

The Necessity of Establishing a Regional Marine Research Program for the U.S. West Coast

The welfare of the marine environment of the U.S. West Coast of California, Oregon, and Washington is hindered by insufficient understanding of ecosystem dynamics and human pressures. Greater coordination, integration, and support of mutually identified research priorities across research organizations on the West Coast are necessary. This level of collaboration is essential to responding to regional ecosystem threats, such as the impacts of human occupation of coastal areas, over-harvesting of marine resources, and climate change. To address this need for collaboration and build on the accomplishments of existing research organizations, this article advocates the establishment of a West Coast regional marine research program (RMRP).     

浅谈香港西铁项目计划管理

香港西铁项目投资规模巨大，工程复杂。为确保工程能按时完工，投入运营，参与各方秉承科学计划管理理念、采用先进技术精心组织实施，业主在招标阶段制定了一套完善的计划管理体系，承包商能够利用先进技术编制了全面、详细、形象的施工计划并加以实施，咨询工程师能够严格把关，协调各方关系，确保了项目顺利完工。     

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该文介绍了浙江省台州椒江二桥主塔墩桩基施工平台直接利用桩基钢护筒作为平台的基础的施工技术。其与常规的钢管桩基础平台相比,具有结构设计新颖、缩短工期、节省材料等优点。根据钢护筒的设计特点,钢护筒的承载能力、防冲刷能力、安全性能、稳定性更由于钢管桩独立平台结构,可以在类似施工条件的工程中推广。