Spain: highs and lows of 20 years of HSR operation

This paper has been written in response to the Viewpoint contribution by the author Button (2012) entitled: “Is there any economic justification for high-speed railways in the United States?”. In this article, the Spanish HSR high-speed rail network is used as an argument against certain HSR investments. Several of the data presented by the author are misleading and some of the information given in connection with Spain is incomplete. As the Journal of Transport Geography is widely read by policymakers and the scientific community, Button’s misrepresentation could cause serious damage. We therefore set out to clarify the data used by Kenneth Button and to explore some points in greater detail, although in no case eschewing criticism of Spain. Although excessive Spanish investment in public infrastructure over the last twenty years has probably had a negative impact on the real estate bubble, investments in HSR infrastructure in Spain have specifically been accompanied by two particular facts that need to be distinguished from other countries’ experience. These facts cannot be overlooked and will be discussed in this paper. They relate firstly to the total amount of European funds used in HSR construction and secondly to the technological and scientific innovations developed in Spain linked to the HSR market.     

创新铁路运输业竞争理论模型研究

通过对竞争理论的研究,提出了铁路运输竞争的概念及分类,建立了铁路运输内部竞争和外部竞争模型;特别是通过对现行中国铁路运输区域管理(铁路局管理)模式的实证分析研究,建立了铁路现有区域管理模式下的竞争模型,在此基础上提出了市场经济条件下、实现充分竞争的新型铁路公司竞争模型,即通过改革后使任一客户(旅客或货主)在同一地区可以选择不同铁路运输公司为其服务,建立起铁路运输企业间的内部充分竞争机制,对铁路运输改革、打破运输垄断、引入竞争机制具有一定的理论意义和重要的现实参考价值。     

一体化发展策略下的轨道交通枢纽建设

轨道交通的枢纽建设在实现城市交通发展一体化中起着至关重要的作用。在总结上海轨道交通多个枢纽建设和运营经验的基础上，提出在一体化发展策略下建设轨道交通枢纽的创新理念，包括“由多线集中换乘到分散换乘”的网络规划理念、由“零距离换乘”到“以时间换空间”的运营安全理念、注重客流组织“单循环”流线的换乘效率理念、实现立体化交通组织的“人车分流”理念、注重细节的“以人为本”理念以及车站周边空间的一体化开发理念，最后从规划、设计、运营、服务、开发五个层面提出轨道交通枢纽建设的具体要求，为未来轨道交通枢纽的规划和建设提供参考。     

In-transit perishable product inspection

We determine the value of monitoring perishable freight in-transit for a single vehicle traveling from an origin to a destination. We develop a computationally practical approach for determining the optimal expected cost function and an optimal policy, based on an infinite horizon partially observed Markov decision process model. Structural properties of the optimal expected cost function and optimal policy are determined. These results can lend insight when deciding whether to acquire the capacity to monitor freight status in transit and what actions to take, based on the data from the in-transit monitoring, that optimally increase expected supply chain productivity.     

清代食盐流通体制中“引岸制”之分析

清政府采取"引岸制"食盐运销体制,赋予一些商人食盐垄断权,商人因之获得暴利,国家只对盐商进行管理和征税,从而使财政得到保证,进而形成了官商相互勾结共分盐利的局面。"引岸制"虽然在最初满足了国家财政和商人逐利的目的,但最终的结果是食盐商品成本上升,价格高昂,流通阻滞,进而导致国家政治进一步衰败,法制进一步瓦解。     

优化物流运营效率下的交通运输规划模式探究

在前人研究的基础之上,对优化物流运营效率下的交通运输规划模式做了大体的介绍,分析了我国现阶段物流交通运输规划模式,指出其不足之处,然后对优化物流运营效率下的交通运输规划模式做出展望。     

物流运输运作成本控制研究分析——以某化工公司为例

从运输成本的构成入手,分析了影响运输成本因素、物流成本与运输成本之间的关系,在此基础之上,以上海某化工企业为例,分析研究了进行物流系统优化过程中运输成本控制的方法和采取的具体策略。     

探讨交通运输机械针对性维修策略与应用

根据当前我国交通运输机械针对性维修的整体发展状况,分析了我国交通运输机械维修的发展方向,从而进一步探讨了现代交通运输机械维修的策略和具体技术应用所遇到的挑战及总体发展趋势,并针对具体维修策略,提出一些关于交通运输机械针对性维修方面的具体措施和发展思路。     

Transportation rates and plant location in oligopolistic competition with sequential entry

This paper examines the impact of quantity-discounted transportation rates on location patterns of oligopolistic competition with sequential entry. When transportation rates are constant, Hwang and Mai (1990) show that the entrant locates at the same point as the existing firms if the production function exhibits constant returns to scale. The entrant will locate farther away from (closer to) the market than the existing firms do if the production function exhibits increasing (decreasing) returns to scale. This paper shows that Hwang and Mai's results need not hold when transportation rates are a function of quantity shipped and distance traveled.     

倏逝波在一维氧化硅亚微米波导线中传输特性的研究

[HTK]基于光学倏逝波原理的光纤或波导传感器是目前光学传感器领域的重要发展方向之一,而倏逝波在其中的传输特性是决定该类传感器敏感特性的关键因数.利用倏逝场理论分析了直径102～103nm的一维氧化硅亚微米光波导在其直径与外部介质(折射率)变化时倏逝波的穿透深度.实验结果表明,亚微米光波导的传输损耗将随着波导尺寸和外部环境折射率的变化而变化,倏逝波的传输方式非常适用于高灵敏度探测,可应用于光化学传感器和生物化学传感器的设计.