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61.
The objective of this study is to provide a strategic evaluation of the mitigation of CO2 emissions via modal substitution of high-speed rail for short-haul air travel on the Sydney–Melbourne, Australia city-pair from a life cycle perspective. It has been demonstrated that when considering CO2 emissions from vehicle operations, the modal shift from air to high-speed rail on this city-pair has the potential to provide a means of CO2 mitigation. However, uncertainty exists with regard to the level of mitigation potential when considering the whole-of-life performance of the systems. Given the significant difference in the infrastructure requirements between the air mode and the high-speed rail mode, this study quantifies the life cycle CO2 load attributable to each system and examines the effect on CO2 mitigation potential. The study concluded that while the inclusion of the linehaul infrastructure did increase the CO2 load associated with high-speed rail mode, it did not equate to or exceed the CO2 load per trip as experienced by the air mode. The avoided annual life cycle CO2 emission in the target year 2056 was 0.37 Mt representing an 18% reduction when compared to the air mode only on the city pair. In fact, the scenario comparison indicated that the substitution of high-speed rail for short-haul air travel on the city pair resulted in CO2 emissions avoidance throughout the longitudinal period.  相似文献   
62.
为防止北京市旅游高峰期间景区周边交通混乱以及城市交通路网负荷增加,选取北京市三 处景点进行问卷调查,将游客的年龄、是否有车、月收入、同行人数及同伴类型等数据作为影响游客交通方式选择的因素。与此同时,对所需数据进行有效性检验,进而分析不同游客的出行方 式特性,利用非集计模型对游客的交通方式选择行为进行研究。结果显示:游客的年龄、是否有车、月收入、同行人数以及同伴类型这几类因素对游客的交通方式选择的影响均显著,并得到游 客对私家车、出租车、地铁及公交车这四类交通方式选择的比例,分别为17%, 7%, 54%, 22%。研究表明,北京市旅游交通方式的需求以公共交通为主,尤其是对轨道交通的需求,为此建议进 一步加大北京市旅游公共交通系统建设,提高旅游交通的服务质量。  相似文献   
63.
为了深入分析出行者的汽车共享选择行为,首先以技术接受模型和计划行为理论为框架,将对汽车共享选择行为具有影响的心理因素整合到传统的离散选择模型之中,形成混合选择模型.然后,基于南京市的实证调查数据,运用混合选择模型对出行者的汽车共享选择行为进行研究.结果表明,出行者对于汽车共享的感知有用性、感知易用性、行为态度、知觉行为控制等心理态度潜变量对其选择行为产生显著的正向影响,混合选择模型比传统不带潜变量MNL模型对实证数据具有更高的拟合度.  相似文献   
64.
Parents compete for high-quality education for their children by enrolling them in good schools. However, in a Chinese mega-city like Beijing, three factors jointly lead to the spatial separation between schools and homes: the centralized public goods provision mechanism, the historical dependency in school location, and the constrained supply of housing in downtown. Without an adequate number of school buses, this spatial separation of schools and homes triggers the numerous long-distance driving-to-school trips by private vehicle during workday morning rush hours in Beijing. We use the start and end dates of “school holiday” as exogenous repeated shocks to the aggregate traffic congestion, and employ the two-stage least squares (2SLS) regression approach to examine the congestion and pollution consequences of such driving-to-school trips in Beijing. We find that, all else being equal, workdays during school holidays have a traffic congestion index 20% lower than that of non-school-holiday workdays. Such a sharp reduction in congestion leads to a significant decrease in PM10 concentration. Policymakers should lower such “extra” congestion and environmental costs via optimizing the spatial balance between school supply and demand.  相似文献   
65.
港珠澳大桥将改变珠江口东西两岸之间的空间运输联系方式,从而改变整个珠三角地区的物流格局.从珠三角地区城市空间布局结构、产业特点出发,总结珠三角地区物流业特点,对港珠澳大桥影响珠三角物流格局的途径进行介绍;并逐一分析港珠澳大桥建成后对香港、深圳、珠海等珠三角主要城市物流业的不同影响.  相似文献   
66.
Recently, there has been a surge of interest in Tradable Credits (TC) as an alternative measure to manage the growth of personal car use. This paper summarises the results and methodologies of studies that have sought to anticipate the behavioural responses to several proposed TC schemes that target personal travel. In a critical reflection on this work and in an attempt to inspire future research, we argue that future empirical studies on TC behaviours can greatly benefit from insights from the fields of behavioural economics and cognitive psychology. Therefore, in the second part of the paper, we bring together behavioural concepts from these fields that are relevant in a TC decision-making context. Based on observations from current TC studies and the behavioural mechanisms identified in the second part of the paper, we propose promising directions for future research on understanding the impact of TC on personal car travel.  相似文献   
67.
Three weather sensitive models are used to explore the relationship between weather and home-based work trips within the City of Toronto, focusing on active modes of transportation. The data are restricted to non-captive commuters who have the option of selecting among five basic modes of auto driver, auto passenger, transit, bike and walk. Daily trip rates in various weather conditions are assessed. Overall, the results confirm that impact of weather on active modes of transportation is significant enough to deserve attention at the research, data collection and planning levels.  相似文献   
68.
Travel to and from school can have social, economic, and environmental implications for students and their parents. Therefore, understanding school travel mode choice behavior is essential to find policy-oriented approaches to optimizing school travel mode share. Recent research suggests that psychological factors of parents play a significant role in school travel mode choice behavior and the Multiple Indicators and Multiple Causes (MIMIC) model has been used to test the effect of psychological constructs on mode choice behavior. However, little research has used a systematic framework of behavioral theory to organize these psychological factors and investigate their internal relationships. This paper proposes an extended theory of planned behavior (ETPB) to delve into the psychological factors caused by the effects of adults’ cognition and behavioral habits and explores the factors’ relationship paradigm. A theoretical framework of travel mode choice behavior for students in China is constructed. We established the MIMIC model that accommodates latent variables from ETPB. We found that not all the psychological latent variables have significant effects on school travel mode choice behavior, but habit can play an essential role. The results provide theoretical support for demand policies for school travel.  相似文献   
69.
考虑城市大客流通勤者跨区域出行需求,结合城市公交线网中乘客出行密集、客流走向规律等特点,提出一种跨区域定制公交的搭乘方案. 通过改进的Q-learning 模型对公交线路进行优化,为城市通勤者提供更加便捷和高效的出行服务. 通过综合路段拥堵状态、乘客需求及居民小区位置,设定了Q-learning 强化学习的奖惩函数,提升定制公交区域路径的直线系数、满载率、通行时间. 结果表明,所提出的改进方法能够降低通勤者跨区域通行的旅行时间,有效提高髙峰时段定制公交线网的通行效率.  相似文献   
70.
从路段实际功能出发,提出基于路段与路径行程时间序列的相关性识别关键路段的方法.借鉴蒙特卡洛思想,以真实数据构造10万条随机路径验证该方法的可行性,并识别出对上海市路网行程时间有关键影响的路段集合.以上述集合为参照,利用模糊聚类及迭代累计平方和算法提取路段行程时间序列特征并构造两个新变量,结合基础属性建立二项Logit模型,从而主动查找关键路段.比较该模型与基础模型、随机分类器查找效果表明:基于最大归一化行程时间曲线聚类,其结果对关键路段识别模型的性能有提升效用;行程时间对数差分序列的结构性变点在路网和路段级别均有明显时间聚集特性,虽然其个数与路段关键性无明显关系,但其与常见波动程度指标相关性小,可保留用于描述行程时间波动常发性和聚集性.  相似文献   
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