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该文阐述了绿色技术的概念,首次建立绿色道路内涵方程式,明确界定道路建设中绿色技术应涵盖节能、降耗、减排、防灾四方面内容,并详细介绍了绿色道路技术研发及在浦东新区世博配套工程建设中的运用。 相似文献
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在分析现有交通设施安全距离有关规定的基础上,运用爆炸毁伤理论,对2000磅级精确制导弹药的毁伤半径进行了分析和计算,分别得到桥梁钢筋混凝土部位和钢结构部位与邻近重点目标的安全距离,其分析过程和计算结果可为进一步形成标准规范提供依据和借鉴。 相似文献
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Hwa-Joong Kim Young-Tae Chang Paul T.-W. Lee Sung-Ho Shin Min-Jeong Kim 《Maritime Policy and Management》2013,40(1):103-122
This paper considers a multimodal transportation problem, which is the problem of determining the transportation flow, i.e. volume of container cargoes, and the transportation mode in each trade route, for the objective of minimizing the sum of shipping and inland transportation costs. The problem takes account of two restrictions: maximum cargo volumes capacitated at each seaport and maximum number of vehicles available at each transportation mode. To solve optimally the problem, this paper employs a mixed integer programming, which is an operations research technique. A case study is performed on the container cargo data in Korea and we draw several implications to improve efficiency in the transportation of international trade cargoes in Korea. 相似文献
337.
Abstract Existing origin constrained and doubly constrained gravity models have not been compared, theoretically or empirically, in terms of their forecasting power. Due to the newly advanced technology of intelligent transport systems, the expanded data presently available have made various models more comparable in terms of forecasting power. This paper uses archived automatic passenger counting (APC) data for urban rail in the Seoul metropolitan area. The APC data contains information about each trip's origin, destination, ticket type, fare, and distance on a daily basis. The objective of this paper is to compare the goodness-of-fit of aggregate and disaggregate gravity modeling using these data. A Hyman aggregate gravity model is used as the aggregate model without the spatial effect. The disaggregate model adopts a multinomial logit as the destination choice model with the spatial effect. In general, while the formulation of aggregate and disaggregate gravity model models are similar, the calibration and parameter estimation methods of the two models are different. As a result, this empirical study demonstrates that the variation in goodness-of-fit and forecasting power largely depends on the estimation method and selected variables. The forecasting power of the disaggregate modeling approach outperforms that of the aggregate model. This paper further confirms that spatial arrangement plays important roles in gravity modeling. 相似文献
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Justin S. Chang 《运输评论》2013,33(3):325-350
Abstract A two‐way interaction between transport and land‐use has been one of the central research topics of transport studies. Thus, it is not surprising that there have been numerous approaches taken to investigate this reciprocal relationship. This paper critically examines the existing literature to see how effectively the current models represent this mutual interaction. This examination process intends to form a prototype reference that compares and contrasts the advantages and disadvantages of the various models. This undertaking is dealt with based on theoretical, methodological and operational characteristics of a respective model. Some conclusions and suggestions are also drawn. 相似文献
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对纤维增强聚合物(FRP)格栅加筋混凝土梁的弯曲行为和破坏模式进行了试验研究。采用复合材料制备了3条纵向肋和4条纵向肋2种不同构造的平面正交格栅,埋入混凝土梁,并对加筋混凝土梁进行四点弯曲试验。结果显示,在本研究采用的混凝土梁尺寸条件下,3根纵向肋的复合材料格栅加筋梁以弯曲破坏模式为主,而4根纵向肋的格栅加筋梁则以局部剪切破坏模式为主。试验结果表明,3根纵向肋的格栅充分发挥了复合材料的抗拉特性,具有更高的加筋效率。 相似文献