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.     

Urban Transport and Sustainable Transport Strategies： A Case Study of Karachi, Pakistan

The uncontrolled growth in urbanization and motorization generally contributes to an urban land use and transportation system that is socially, economically, and environmentally unsustainable. This paper uses Karachi as a case study, which is the largest urban and economic centre of Pakistan, passing through an uncontrolled phase of rapid urbanization and motorization. The paper first reviews research related to sustainable transportation systems to comprehend the concept of sustainable development and transporta-tion. The paper then evaluates the existing transportation and infrastructure system, national transportation policies, and urban transportation projects to determine if the current paradigm is moving toward or away from sustainable transportation. Furthermore, the principles for sustainable urban transportation are devel-oped to see what significance national transportation policies have given to urban transportation from a sus-tainable transportation point of view. Finally some strategies are suggested, adoption of which may lead to a sustainable urban development and transportation system in Karachi.     

组合动力技术的未来应用

 组合动力将两种或以上单一类型的动力有机结合，结构相互融合，功能相互补充，大大拓展了飞行包线、提高飞行效率，在临近空间高速飞行器、重复使用航天运输系统等领域具有重要应用。介绍了组合动力基本分类及工作原理，综述了组合动力技术在临近空间高速飞行器、重复使用航天运输系统等领域的应用，总结了组合动力飞行器发展趋势及主要关键技术。     

阳煤集团一矿北丈八井3#煤和15#煤分运系统的改造

针对目前阳煤集团一矿北丈八井1#强力皮带混合运输3#煤和15#煤、影响矿井产量大幅度提升的现状,对北丈八井3#煤的运输系统进行了改造,实现了3#煤和15#煤的分别运输,解决了北丈八井15#煤运力不足的问题.     

智能化交通管理

简要介绍了智能化交通管理的基本概念，重点介绍了电视交通探测系统（ＶＴＤＳ）的功能、特点及优点。     

火铺矿现有生产水平的技术改造

本文借助计算机随机服务系统模拟的方法,对火铺矿的现有生产状况进行了分析、模拟,定量地确定了各个生产环节的能力,找出了薄弱环节,提出了相应的技术改造措施,并对各个技术改造方案及设备匹配进行了模拟,从而确定了最佳的技术改造和设备匹配方案。     

矿井下直流杂散电流的危害与防治措施

井下架线电机轨道运输系统，通常把钢轨作为电源回线。由于钢轨与大地直接接触，漏电量较大，加之钢轨接缝连接不善，致使钢轨中的电流，相当大的一部分被大地及其附近的金属管线分流，这部分电流称其为直流和铠装的金属外壳，重则能引起电雷管的先期爆炸、诱发瓦斯、煤尘爆炸。因此，降低杂散电流是消除井下运输系统事故隐患的重要方面。     

粘土用作铁水聚渣,保温材料的研究

本文首次研究了粘土用作铁水聚渣、保温材料的可行性。结果表明:粘土对铁水聚渣、保温效果好,热幅射小、污柒轻,对铁水的化学成分、金相组织、机械性能和铸件质量均无不良影响;与传统使用的稻草灰和近几年应用的珍珠岩相比,其经济效益显著。     

用X光透视装置观察钛漳-铁水反应过程

报道了用X光透视装置观察渣铁反应过程。普通渣与铁水反应时渣铁界面清晰,起泡但无泡沫。钛渣与铁反应时,随界面处Ti(CN)的生成、气泡的搅动,铁水逐渐向渣中乳化。重熔乳化了的渣铁样,开始界面清晰、分离良好。渣-铁反应生成的气泡能在渣面形成泡沫,主要由于Ti(CN)微粒起到了稳定剂的作用,但形成的泡沫有限。