Accessibility of a Destination-Based Transportation System: A Large Airport Study

The accessibility of a destination-based transportation system is defined to quantify the performance of transportation systems which access a distinct destination. The access cost is used to reflect the utility of the transportation system including the fatigue and inconvenience in the total cost. The cost is quan- tified by two coefficients which represent the different characteristics of various people. The average cost and the income-relative accessibility are used to describe various aspects of the accessibility and to evaluate the accessibility of a destination-based system. A case study uses data from the Kunming transportation system to evaluate the accessibility of the present city airport. The calibrated coefficients are then used to evaluate the transportation system to the new Kunming international airport. The results show that this transportation accessibility evaluation can be combined with transportation planning to study transportation sub-systems.     

IF钢再结晶退火过程中析出相行为研究

对ＩＦ钢在退火过程中二相粒子的演变规律进行了研究,结果表明：退火以前形成的二相粒子,如ＴｉＣ,在经过罩式退火和连续退火后,其尺寸,形状和分布有较大的区别;在连续退火中不形成新的析出相,而在卓式退火中形成两类新的析出相－ＦｅＴｉＰ相和（Ｔｉ,Ｍｎ）Ｓ相,这是首次报道有关ＦｅＴｉＰ相在含Ｐ,Ｍｎ较低（Ｐ≤０．０１％,Ｍｎ〈０．２％）的ＩＦ钢中析出,以及Ｍｎ以（Ｔｉ,Ｍｎ）Ｓ相的形式在罩式退火中析出,还     

能源稳定型风光互补发电系统在道路照明中的应用

为了解决目前风光互补发电系统用于道路系统路灯照明的供能不稳定性,考虑利用车辆行驶引起的空气流动转化为电能来弥补自然风能的不足,构成新的风光互补发电系统。该文基于一定的理想化假定条件,根据功能原理得到了由于车辆行驶引起的空气流速与车速的定量关系,进而分析能量的供求关系。通过对首都机场高速公路的情况进行算例分析,计算结果显示:考虑车辆行驶引起的空气流动的能量的情况下,首都机场高速公路的照明能源完全可以依靠新型风光互补发电系统提供。     

Optimizing Work Zones for Two-Lane Urban Road Maintenance Projects

Road maintenance work brings costs to the government and delays to users. The setting up of work zones often leads to severe congestion during peak hours, especially in busy urban areas. A road maintenance delay model is presented here that includes consideration of excessive traffic flow and non-motorists. Atrial-and-error method is used to find the optimal work zone length and the best work starting time to minimize the total cost of maintenance and delays. A numerical example with a sensitivity analysis is also given. The results show that optimal starting time is not sensitive to the flow speed and the increase of work zone speeds sharply reduces the total cost when the road is congested.     

Road Resources Distribution and Evolution Analysis Using a Species Competition Model for Improving Road Equity

The paper analyzes the equity of road resources distribution in urban areas by modeling the competitive relationship among different road users. A logistic model is used to describe the development of different traffic modes in the transportation network. The system is similar to the species competition model, so a two-species model is used to analyze the relationship between users based on the stability of the equilibrium points. The Lotka-Volterra model is then used to describe the multi-species cases with numerical examples, showing that this model can describe the effects of the road space distribution on the competitive user relationships. Policy makers must ensure the equity of road resources distribution so that each urban transportation mode is properly developed for sustainable social development.     

道路设施项目投资公平性的评价方法

传统的交通项目评价集中于对项目效率性的判断,忽视了公平性的分析,评价结果不够全面合理。该文引入区域公平性、归属公平性、最优分配的概念,提出了道路项目投资公平性问题的表现形式,并基于W ilson熵分布假设建立评价模型。该模型考虑了区域物价、地价、收入水平的差异以及社会对公平性的认识程度等因素,体现了对不发达地区和交通弱势群体的效益补偿作用,且与最小方差法相比有更好的感度,从而为保障社会基础设施建设中资源的合理、有效分配提供了重要的理论依据。     

高速公路间断放行的能耗和排放影响

公路交通业是能源消耗大户,也是催生雾霾天气形成的废气污染物的重要排放源。雾霾天气会使交通不能正常运行,为此制定的交通管理措施影响到能源的消耗和污染物的排放。该文从节能减排的角度,在制定最优的浓雾条件下高速公路间断放行措施中尽量减少车辆的能耗和排放。通过建立交通流元胞自动机(CA)模型,探讨了不同的间断放行措施对能耗和排放的影响。研究结果表明:在满足每车道最低交通量和交通安全要求的前提下,间断放行数量有一定的区间限制,采用区间下边界的数值时,放行车队通过雾区时平均每辆车的能耗最小,同时CO和NOx排放最少。     

对开发贵州旅游业的几点看法

七月下旬,我有幸作客贵阳师范学院。此间承蒙吴院长、王副院长、外语系教师以及其它教职员工和学生们热情款待,我不胜感激。玛丽·伯杰对我说过,师院曾予她以特殊的优待。这话是公正的。她委托我向所有的朋友们转达她最好的祝愿。我此次来访的目的在于探索贵校与我所代表的密执安州大学——奥克兰大学之间开展互利交流的可能性。我们对此已经进行了几次卓有成效的研讨,我希望这将促进今后的交流。     

Applied Study of Price Discrimination Implemented on a Two-Path Route Expressway

Introduction In Japan, the Japan Highway Public Corporation (JH) is in charge of construction, operation, and manage- ment of both certain toll roads and the inter-city ex- pressway system throughout the country. The certain toll roads and inter-city expr…