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51.
为探讨共享单车用户在不同影响因素下对现金奖励调度策略的接受程度,设定了针对共享单车用户的调查问卷,并在济南市进行了调查,得到519份有效问卷。基于扩展的计划行为理论(Extended Theory of Planned Behavior, ETPB)模型和相关结构方程模型(Structural Equation Model, SEM),设定了社会规范、支付能力、体力、感知服务、感知绿色价值5个构念以及5个相关假定,以测度不同奖励调度情境下共享单车用户对奖励策略的接受程度。结果显示,支付能力和体力对用户接受调度的影响程度最大,其次是社会规范和感知服务,感知绿色价值的影响程度最小。在此基础之上,提出了增大站点密度、实行现金奖励及提高车辆质量等建议,以降低运营成本、提升用户满意度与车辆使用率。 相似文献
52.
The relationship between land use and the utility of automobile travel is examined by refining the utility concept, particularly by combining the microeconomic utility theory, which is concerned with the disutility of travel, and the perspective on the positive utility. A conceptual model is accordingly developed and then adjusted considering different purposes of travel. The purpose-specific models are tested through a Multiple Indicators Multiple Causes approach in Seoul, Korea, using datasets from a sample survey and geographic information systems. The major finding is that land use affects the utility mainly by changing synergy and affective utility rather than instrumental utility, which encompasses disutility variables. Among land use variables, the utility is found to be the most sensitive to the number of transit facilities for commuting and shopping travel and land use balance for leisure travel. 相似文献
53.
A conceptual design framework for collision and grounding analysis is proposed to evaluate the crashworthiness of double-hull structures. This work attempts to simplify the input parameters needed for the analysis, which can be considered as a step towards a design-oriented procedure against collision and grounding. Four typical collision and grounding scenarios are considered: (1) side structure struck by a bulbous bow, (2) side structure struck by a straight bow, (3) bottom raking, (4) bottom stranding. The analyses of these scenarios are based on statistical data of striking ship dimensions, velocities, collision angles and locations, as well as seabed shapes and sizes, grounding depth and location. The evaluation of the damage extent considers the 50- and 90-percentile values from the statistics of collision and grounding accidents. The external dynamics and internal mechanics are combined to analyse systematically the ship structural damage and energy absorption under accidental loadings. 相似文献
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ABSTRACT The logistics environment between China and Korea has been changing rapidly in line with the ‘Go West’ policy of international trade and logistics area. The policy includes the BRI, Western Development Strategy, and Korea–China FTA. Against this background, the Korea–China train ferry (KCTF) is being newly illuminated as an alternative mode to cope with the logistics environment between Korea and China. One of the key success factors of the KCTF depends on, among others, shippers’ perception, which will affect the choice and the successful operation of the KCTF. From this perspective, this paper develops seven hypotheses based on the Theory of Reasoned Action (TRA) and Technology Acceptance Model (TAM). We test these hypotheses using Structural Equation Modeling (SEM) to explore the structural relationship between shippers’ behavioral beliefs influencing the perceived usefulness, the attitude toward and intention to choose the KCTF. The test results confirm that among the behavioral beliefs, transport accessibility in association with an efficient network of inland roads and railway networks is an important prerequisite. In addition, we verified a high statistical significance in the structural relationships among perceived usefulness, the attitude toward and the intention to choose the KCTF. 相似文献
56.
王书卫 《铁道标准设计通讯》2015,(1):37-41,46
为了掌握钢轨扣件减振橡胶中阻尼的分布及其随振幅和频率的变化规律,对减振橡胶元件受压和受剪两种扣件进行了试验研究。建立钢轨扣件减振橡胶非线性弹性力和混合阻尼叠加的动力学模型,完成模型参数识别及结果检验。根据所建立的动力学模型计算各试验工况下的弹性变形能、阻尼耗能和结构损耗因子。分析发现:压缩和剪切两种扣件减振橡胶的阻尼参数随振幅和频率的变化规律相似,弹性变形能、阻尼耗能和结构损耗因子均随振幅的增大而显著增大,而受频率的影响较小。相同工况下,压缩型扣件减振橡胶的结构损耗因子远大于剪切型扣件,说明压缩型扣件在发挥减振功能时,其耗能特性优于剪切型扣件,而隔振特性劣于剪切型扣件。因此,在钢轨扣件创新设计时,可以通过控制减振橡胶压-剪组合变形,来实现扣件隔振和衰减振动能量两功能的均衡发挥,将结构损耗因子作为设计过程中的控制指标。 相似文献
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城市轨道交通信号控制系统在其安全性、可靠性、可用性和可维护性方面都有很高的要求,尤其针对软件安全完整性等级为4级(SIL4)的系统或子系统,在其测试方法和流程方面都有国际性的标准参考(如欧洲标准EN50128)。测试在遵从标准的前提下,其测试方法应用和测试实践经验也是有所不同的,介绍了软件安全完整性的概念以及标准要求的各种测试流程,并对实际操作方法加以分析,深入探讨了轨道交通信号控制系统软件安全完整性集成自动化测试平台的设计、应用方法和评估。 相似文献
58.
研究目的:本文通过CFG桩完整性检测,对空洞、夹泥、夹土、夹砂浆、缩径、严重离析(蜂窝状、砂石分离状)等施工原因引起的问题进行研究.为确保CFG桩质量完整,应从施工预防着手,制定施工措施,加强施工质量控制.研究结论:CFG桩混凝土灌注时要严格执行"灰包钻"施工法,即灌注混凝土时始终混凝土灌注面包着钻头0.5~1 m 同... 相似文献
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Introduction Structural evaluation of pavements provides awealth of information that concerns the expected be-havior of pavements[1]. Different asphalt pavementdesign and evaluation methods are described inRefs.[2-9]. Refs.[2-5,9,10] use two design meth-o… 相似文献
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