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401.
为了解决中国公路运输的“瓶颈”问题, 分析了现有公路网的干线路网和基础路网的范畴, 研究了公路建设费用、土地占用成本、运输成本、路网使用效率4个因素对基础路网布局规划的影响, 以有利于国民经济和社会发展产生的运输需求为目标, 构造了基础路网规划的四因素模型和算法, 开发了模型与算法的集成软件ArcGIS。分析结果表明: 规划后的基础路网使用效率能相对保持在70%~80%内, 能够清楚地反映研究区域的运输需求流量和流向, 因此, 集成软件ArcGIS可行。  相似文献   
402.
高伟  高兴 《交通信息与安全》2016,34(3):108-115,125
定量分析影响管制员工作负荷的因素对于实现管制员工作负荷的精确评价具有重要意义。综合考虑扇区交通运行情况以及管制员工作表现,确定了14个影响管制员工作负荷的因素指标。利用灰色关联熵确定指标权重,建立了基于加权灰色关联度的管制员工作负荷影响因素分析方法,并对分辨系数的取值进行了优化。用北京01/19区域管制扇区的雷达模拟机数据对上述方法进行验证。结果表明,陆空通话次数、设备操作次数、扇区进出指数分别是影响管制员工作负荷最重要的3个因素,其加权灰色关联度分别为0.8440,0.7961,0.6935。同时,加权灰色关联度的排序结果与层次分析法得出的管制员主观排序结果基本一致。采用加权灰色关联度对管制员工作负荷影响因素进行分析能够揭示各影响因素的重要程度。  相似文献   
403.
为充分挖掘公共自行车时空出行特征,探讨城市空间环境与骑行需求的潜在联系。以宁波市中心城区为案例,基于公共自行车IC卡数据获取出行时空变化规律,在验证租、还车需求具有空间自相关性的基础上,通过建立空间滞后模型,分析了人口密度、道路分布、公共交通、站点配置和建成环境因素对骑行需求的影响。研究表明:①工作日、非工作日内租、还车需求的全局Moran's I分别为0.294,0.281,0.272和0.271,表现出显著的空间正相关性;②各模型的拟合优度R2分别是0.431,0.424,0.412,0.401,具有良好的拟合效果与解释性;③道路分布、建成环境变量对公共自行车使用的影响效应存在时间差异,其中公交专用道里程与非工作日内的站点需求量呈负相关,工作日内POI混合度对租、还车需求具有正向引导作用。  相似文献   
404.
The purpose of this study is to understand the effects of the influential factors that affect the sustainable development of new energy vehicle in China, investigate the cause-effect relationships among them, and propose some appropriate policies and efficacious measures for the policy-makers to promote its sustainable development. Interpretative Structuring Modeling was used to identify the critical factors affecting the sustainability of China’s new energy vehicle industry and to find the potential relationships among the factors; subsequently, fuzzy Decision Making Trial and Evaluation Laboratory was employed to investigate the cause-effect relationships among the influential factors and to prioritize these factors. The results reveal that technological maturity, technological standards for new energy vehicles, and funds on R&D of new energy vehicles are the three most important driving factors for promoting the sustainable development of new energy vehicle industry of China. Some implications were also proposed for China’s authority. The success factors and strategic implications of new energy vehicles in China were investigated in a multi-criteria analysis approach.  相似文献   
405.
The use of traffic sensors to acquire real‐time traffic information for intelligent transportation systems is becoming increasingly common. It is a challenge to determine where these sensors should be located to maximize the benefit of their use. This paper aims to illuminate the interaction of the sensor location problem (SLP) and its influencing factors, and to reveal the influencing mechanisms between those factors and the optimal sensor numbers. Firstly, we sum up the factors that influence the SLP for freeway corridors in detail and present the mathematical formulation of each factor. Then, given the parameters, which are derived from those influencing factors, the maximum integration value model (MIVM) and simplified MIVM are proposed for addressing the SLP. Finally, a real world case study, in which the simplified MIVM is used, is presented to illustrate how these factors influence the optimal sensor numbers and the maximum integration value, and also leads to the typical influencing patterns of those factors for freeway corridors. The results of the case study also demonstrate the effectiveness of the model and problem solving scheme. What is more, the suggestions for using the findings hereof in practical applications are put forward. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
406.
This paper describes a comprehensive panel data collection and analysis at household level, including detailed travel behaviour variables and comprehensive in-home and out-of-home activities, individual cognitive habits and affective behaviours, the rate of physical activity, as well as health related quality of life (QoL) information in the Bandung Metropolitan Area (BMA) of Indonesia. To our knowledge, this is the first attempt to collect an individual’s activity diary over an extended period as it captures the multi-tasking activities and multidisciplinary factors that underlie individual activity-travel patterns in a developing country. Preliminary analyses of the collected data indicate that different beliefs, anticipated emotions, support and attachment to motorised modes significantly correlate with different groups of occupation, gender, age, activity participation, multi-tasking activities, and physical health, but not with different social and mental health. This finding highlights the reason why implementing car reduction policies in Indonesia, without breaking or changing the individual’s habits and influencing his/her attitudes have not been fruitful. The results also show that endorsing more physical activities may result in a significant reduction in the individual’s motorised mode use, whilst individuals who demonstrate a tendency to use their spare time on social activities tend to have better social health conditions. Furthermore, undertaking multi-tasking out-of-home discretionary activities positively correlates with better physical health. All these highlight the importance of properly understanding and analysing the complex mechanisms that underlie these fundamental factors that shape individual daily activity-travel patterns in developing countries. This type of multidisciplinary approach is needed to design better transport policies that will not only promote better transport conditions, but also a healthier society with a better quality of life.  相似文献   
407.
To assess parking pricing policies and parking information and reservation systems, it is essential to understand how drivers choose their parking location. A key aspect is how drivers’ behave towards uncertainties towards associated search times and finding a vacant parking spot. This study presents the results from a stated preference experiment on the choice behaviour of drivers, in light of these uncertainties. The attribute set was selected based on a literature review, and appended with the probabilities of finding a vacant parking spot upon arrival and after 8 min (and initially also after 4 min, but later dropped to reduce the survey complexity). Efficient Designs were used to create the survey design, where two rounds of pilot studies were conducted to estimate prior coefficients. Data was successfully collected from 397 respondents. Various random utility maximisation (RUM) choice models were estimated, including multinomial logit, nested logit, and mixed logit, as well as models accounting for panel effects. These model analyses show how drivers appear to accept spending time on searching for a vacant parking spot, where parking availability after 8 min ranks second most important factor in determining drivers’ parking decisions, whilst parking availability upon arrival ranks fourth. Furthermore, the inclusion of heterogeneity in preferences and inter-driver differences is found to increase the predictive power of the parking location choice model. The study concludes with an outlook of how these insights into drivers’ parking behaviour can be incorporated into traffic assignment models and used to support parking systems.  相似文献   
408.
山区道路工程多数沿河谷行进,从而与地质环境脆弱带在空间上直接冲突。利用结构模型解析法,确定山岭区沿河公路选线设计主要因素多级递阶结构图的过程,其核心是在选线设计时,首先需要评价工程对环境的影响,尽量控制或减少工程对环境的不利作用,从工程设计源头控制灾害,从而建立了工程与环境协调的山区高速公路选线决策程式。并以西攀高速公路垭口北段为例,介绍了在这种工作模式指导下的具体实施流程。  相似文献   
409.
山区公路冰雪灾害预警评估模型研究   总被引:2,自引:0,他引:2  
利用主成分分析方法对山区公路雪灾因子进行分析,由此得知温度、湿度、降雪量和积雪日数是决定公路雪灾的主要因素。在此基础上,提出基于主因子的专家打分方法的山区公路冰雪灾害强度模型和预警评估模型。运用山区公路冰雪灾害强度模型和冰雪灾害强度分级标准,在预警评估模型的支持下对重庆地区的历史雪灾进行判别和归类,结果与实情基本吻合。  相似文献   
410.
浅谈沉箱预制的安全生产及措施   总被引:1,自引:0,他引:1  
随着沉箱施工能力的大幅提升,沉箱预制施工过程中暴露出的事故隐患也日显突出。文章总结了以往沉箱预制事故教训,对事故产生的原因进行了分析,辩识了沉箱预制过程危险因素,论述了在模板工艺设计、技术措施和管理措施二三个方面应采取的安全措施。  相似文献   
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