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81.
Jen  William  Hu  Kai-Chieh 《Transportation》2003,30(3):307-327
This paper establishes and tests the perceived value model, which is applied to identify the factors affecting the passengers' repurchase intentions on city bus. In this study, perceived value is a trade-off between perceived benefits and perceived costs. And the main part of perceived benefits is service quality. We (1) measured service quality using a multiple-items scale, (2) integrated perceived non-monetary price as a part of perceived costs, and (3) simultaneously incorporated the attractiveness of alternative modes. Data was collected via a questionnaire survey in the Taipei metropolitan area and the model was tested using path analysis performed by LISREL. The results indicate that all causal relationships are statistical significant. Finally, this study concludes by discussing managerial implications and making suggestions for future research.  相似文献   
82.
通过分析国内外换轨周期模式,提出了普速铁路在役钢轨服役状态评估方法和参数,建立了跟踪分析试验段。运用试验段数据统计分析了自上道以来的钢轨伤损与累计通过总质量的关系并掌握了钢轨打磨和使用情况。应用所提出的钢轨服役状态评估方法和参数将试验段原定换轨周期由累计通过总质量7亿t延长到累计通过总质量近10亿t,并分析了换轨周期延长后的经济效益。研究成果为钢轨使用和管理部门延长钢轨使用寿命提供了分析方法和范例。  相似文献   
83.
通过对郑州机务段客运电力机车轴箱轴承的设计疲劳寿命计算以及对机务段多年轴承检测情况进行统计分析,提出了合理延长此类轴承使用周期的建议,以避免因此类轴承使用寿命期规定过短造成的过剩维修,达到节约大量材料和资金的目的。  相似文献   
84.
In this article we attempt to illustrate the potential benefits to Alaskan commercial fisheries expected from enhancements to the Alaska Ocean Observing System (AOOS) through changes in fishery management strategies. In particular we show how the use of improved AOOS data in research, stock assessment, and ultimately fisheries management has the potential to result in significant benefits in the Bering Sea and Gulf of Alaska groundfish and Kodiak king crab fisheries. We show through a case study approach that information such as might be provided by an enhanced AOOS could conceivably contribute over $600 million in additional annual revenue in Alaska's groundfish fishery. In addition we estimate that had the information from such a system been available in the 1970s and 1980s the Kodiak king crab stock collapse could have been avoided and $60 million in annual revenues generated. Benefit estimates (as measured by revenue increases) are based on the assumptions that when better data is delivered those data will be integrated into stock assessment models; when better data are integrated into the models the new data will actually improve the reliability of the models; and when the reliability of the models is improved predictions will be accepted by managers or industry members.  相似文献   
85.
针对FPSO吊车回转行星减速箱第一级存在较高故障率的问题,从回转行星减速箱的设计和原理入手,分析故障的主要原因是内部传动滚针的散落和行星轮润滑失效。把改变行星轮传动机构和改善行星轮润滑条件作为两个方面对减速箱第一级进行升级改造,改造后减少了回转齿轮箱故障率,减少了吊机停机维护时间。  相似文献   
86.
This article describes a novel approach for the binary classification of two‐wheeler road users in a dense mixed traffic intersection. The classification is a supervised procedure to differentiate between motorized and non‐motorized (human‐powered) bikes. Road users were first detected and tracked using object recognition methods. Classification features were then selected from the collected trajectories. The features include maximum speed, cadence frequency in addition to acceleration‐based parameters. Experiments were conducted on a video data set from Shanghai, China, where cyclists as well as motorcycles tend to share the main road facilities. A sensitivity analysis was performed to assess the quality of the selected features in improving the accuracy of the classification. A performance analysis demonstrated the robustness of the proposed classification method with a correct classification rate of up to 93%. This research contributes to the literature of automated data collection and can benefit the applications in many transportation‐related fields such as shared space facility planning, simulation models for two‐wheelers, and behavior analysis and road safety studies. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
87.
甩挂运输是一种先进的运输组织方式,是提高道路运输效率的重要手段,对于促进节能减排,推动道路运输业的发展具有重要意义。本文针对某一具体甩挂运输企业构建数学模型并从固定成本、变动成本两个方面对其进行经济效益评价,从油耗、二氧化碳排放量和污染物排放量三个方面进行节能减排评价,进而论证得出了甩挂运输具有提高经济效益和节能减排的优势。  相似文献   
88.
研究表明在城市交通运行管理中,通常难以实现同时缓解交通拥堵和减少排放的目标.实施道路拥堵收费方案可以有效地管理用户的出行需求,从而减缓交通拥堵,但未必能减少尾气总排放.本文面向多用户类,分别包括不同时间价值的用户(多时间价值用户)和不同车型的用户(多车型用户),通过建立同时考虑拥堵和排放的双目标优化模型,证明多用户类无论基于时间成本准则或者费用成本准则选择路径,都存在一种有效的道路收费方案使帕累托有效流达到用户均衡的状态,实现同时减缓交通拥堵和降低排放的目标.  相似文献   
89.
提出一种针对小文本的基于近似网页聚类算法的Web文本数据挖掘技术,以获得用户感兴趣的近似网页簇系列。试验证明,该算法在保证查全率和查准率的基础上大大提高了搜索效率。由于是针对小文本的数据挖掘,研究的算法时间和空间复杂度都不高,因此,有望成为一种实用、有效的信息检索技术。  相似文献   
90.
SMA-10沥青玛蹄脂碎石混合料和ECA-10易密实沥青混凝土适用于沥青路面厚度为2.5~3.0cm,对于道路改建和养护工程有很好的使用效果和经济效益。文章对比这2种沥青混合料各项性能指标,结果表明高温稳定性和低温抗裂性能相当,都能满足规范要求,考虑经济性性能则SMA-10更能体现出优势。  相似文献   
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