基于空铁联运OD可达性的高铁时刻表优化模型

空铁联运的优势之一在于提高客流起讫点(Origin-Destination,OD)的可达性,为机场所服务的地区提供更多出行机会.考虑"高铁接续航空""航空接续高铁"两类接续服务,引入两类0-1变量表达高铁与航空的接续关系及OD可达关系,提出空铁联运OD可达性约束,描述高铁在空铁换乘枢纽的到发时刻、接续变量和OD可达变量...     

考虑出行费用的就业可达性分析

良好的就业可达性有助于创新职住对接机制，是建设可持续城市的关键问题。既有可达性研究对于出行成本的考虑多局限于出行距离或出行时间，未充分考虑出行费用并研究其对不同出行方式的影响。本文基于互联网地图和工商数据平台的POI(Point of Interest)数据和实时路径规划数据，获取细粒度的就业和出行成本信息，采用改进的两步移动搜索算法，提出考虑出行费用的就业可达性度量方法，研究公共交通和小汽车两种出行方式的就业可达性并评估出行费用对就业可达性的影响。针对北京的案例研究表明：考虑出行费用后，小汽车平均出行成本由仅为公共交通54%变化至高于公共交通6%。就业可达性对出行费用敏感，仅考虑出行时间无法完全体现就业选择与出行成本之间复杂的互动机制。出行费用的影响体现在公共交通与小汽车可达性平均降低7.3%和4.8%；若不考虑出行费用，五环至六环地铁沿线街道的就业可达性会被低估。出行成本对可达性的影响存在阈值效应，阈值越高，影响越小。本文有助于规划者和政策制定者形成就业可达性引领的职住平衡调整策略。     

基于热点探测的城市区域公交可达性研究

提出基于出租车轨迹数据挖掘的城市区域公交可达性评估优化方法. 利用核密度分析和热点探测，识别出租车用户出行敏感区并用出行热度表征区域用户需求，研究敏感区域公交可达性. 从影响阻抗大小的指标出发定义公交可达性，选取影响可达性的关键指标描述阻抗，以各指标与热点值之间的相关性为权重获取公交可达性计算公式. 引入区域公交供需变异系数指标，供需莫兰散点图及区域公交供需差分布图，评价整个城市及热点区域的公交可达性供需情况，识别区域不平衡程度协助公交系统优化供给. 以西安市为例进行分析，结果表明：其区域公交供需的变异系数为1.89，存在一定的不平衡性；根据供需差及散点图的分布规律，识别出优先处理敏感区，采取措施提高其可达性对优化整个城市匹配度最为有效.     

Exploring built environment impacts on transit use – an updated meta-analysis

ABSTRACT

The built environment (BE) is widely accepted to influence transit use (TU). Evidence to date suggests the relationship is dependent on many factors which can be difficult to account for in quantitative studies. This creates barriers to transferring research into practice. Considering many studies together can be useful for accounting for more of the factors impacting transit use. Yet, meta-analysis of research measuring these influences was last undertaken in 2010 based on 18 studies. Since then 90 new quantitative studies have been published. These recent studies use improved methodologies and are conducted in more diverse geographies. This paper reports an improved and updated meta-analysis of built environment impacts on transit use. It compares elasticity estimates from research published pre-and post-2010 and explores the impact of new methods and a more diverse geographical representation on findings. Updated meta-elasticities range from <0.01 to 0.26; a similar range to the 2010 study. However, at the individual indicator levels, more recent results are different. Elasticities for urban density, including population, employment and commercial density, have increased significantly in studies published since 2010, as did that of land use mix. However, measures of local access, design and jobs-housing balance decreased in post-2010 studies. These results confirm the small but imprecise relationship between the BE and TU. Results also suggest that while the range of elasticity impacts is relatively consistent, new study methodologies, notably those that control for regional accessibility and self-selection, and the increasing geographical diversity in study applications, is acting to change BE-TU findings at the indicator level. Research setting and context are important to consider when using empirical results to design BE strategies to promote transit use.     

Factors that affect the ability of people with disabilities to walk or wheel to destinations in their community: a scoping review

ABSTRACT

It is essential that the pedestrian environment accommodates all users so they can participate in everything the community has to offer. However, people with disabilities (PWDs) often find it difficult to navigate this environment because of physical and social accessibility factors. While we know a great deal about which factors act as barriers and facilitators to mobility, we do not know enough about how they influence navigation (i.e. planning a route, en route decisions, and route learning) or how they can be improved. A scoping review was conducted to identify these factors, assess their implications, and suggest future directions. In total, 3394 studies were found and screened, 163 full-text articles were reviewed, and 37 articles met the inclusion criteria for the final review. These studies focused on those with visual impairments, navigating crosswalks, and the cognitive elements of navigation. Future research is needed that includes more types of disabilities, considers the navigational process from planning to arrival, and evaluates interventions.     

站点可达性方法对公交不平等测度的影响研究

基于缓冲区法(Buffer method)的站点可达性是公交不平等测度的基础数据，通常按乘客到站距离计算方式(直线或沿路网)或数量分布方式(随距离衰减或不衰减)对计算站点可达性的直线缓冲区法进行改进，但可达性计算结果差异对公交不平等测度的影响尚不明确。基于此，以浙江省海宁市为例，将直线缓冲区法与路网缓冲区法、直线衰减法、路网衰减法3种改进方法计算的站点可达性与公交基尼系数进行比较。结果发现：按到站距离计算方式(即路网缓冲区法)改进直线缓冲区法使基尼系数降低 13.60%，按乘客数量分布方式改进(即直线衰减法)使基尼系数降低 35.75%，按两种方式共同改进(即路网衰减法)使基尼系数降低40.56%；改进方法均使小区间可达性值差距减小，按乘客数量分布比按到站距离方式的改进效果更明显；市区比农村的公交基尼系数受可达性方法影响更大，这可能与路网、人口分布的城乡差异有关，且不同可达性方法测度城市与农村公交不平等时存在不同甚至相矛盾的结论。研究表明：简化方法会高估公交不平等且对城市与农村影响不同，因人口或路网数据缺失而选择缓冲区法时应核减公交基尼系数值，数据完备时应选用路网衰减法。     

基于出行数据的城市公交网络可达性研究

可达性是评估交通便利程度的有效指标，城市公共交通良好的可达性能够吸引更多人选择这类方式出行.基于公交刷卡、发车时间间隔等多源数据，提出考虑线路和流量的车站等待时间计算方法；利用换乘时间阈值拼接出行数据，获取起讫车站出行时间，建立两阶段机会模型.以北京市为例，评估公交网络实际可达性.研究表明：车站服务可达性和网络可达性均呈现城市中心高、郊区低、沿地铁变化趋势明显的特征，线路越多的车站可达性越高；传统的定值设置方法会低估高可达性车站的可达性水平，考虑流量和线路的等待时间计算方法是有效的.     

交通可达性对居住地选择的影响--以成都市为例

为了解新型城镇化战略下大城市中心区居民外迁至卫星城时的居住地选择行为特征及偏好，选取卫星城居住地周边学校、医院、商业设施、轨道交通车站及到中心区交通可达性作为主要变量。根据家庭成员组成特征将样本家庭划分为5类，对比分析不同家庭居住地选择行为特征及偏好。结合家庭社会经济属性形成了一套包含8种情景的正交设计组合问卷，对成都市中心区居民进行意愿调查，并建立Logit模型对居住地选择行为进行分析。结果表明，学校、医院等主要服务设施的交通可达性及家庭自身属性均对中心区居民外迁行为存在显著影响，同时定量分析各变量对居民选择外迁意愿的影响程度，最后提出有助于中心区人口疏解到卫星城的交通政策和措施建议。     

就业可达性量化方法及分布特征研究——以南京市为例

基于国外传统可达性测算方法,建立适用于中国城市交通特征的就业可达性量化方法。在对比分析常用的四种可达性测算模型的基础上,以南京市为实例,针对老城区分别构建了小汽车和公共汽车出行就业可达性模型,同时建立新城区就业可达性模型,以此分析南京市就业可达性空间分布特征。研究表明：南京市主城区就业可达性随着出行距离增加而提高,且提高程度逐步降低;公共汽车出行就业可达性低于小汽车,在城市外围地区尤为明显;新城区就业可达性远低于老城区,职住失衡以及交通通道欠缺是主要原因。最后,通过借鉴国际城市发展经验,提出南京市不同片区就业可达性改善措施。     

轨道交通站点开发利益影响范围研究

利用零售力法则计算轨道站点被城市各中心吸引的概率,并利用可达性指标计算各站点在单中心影响情况下的轨道站点影响范围,结合以上两模型确定轨道站点开发利益影响范围计算模型。该模型能够用于城市多中心情况下轨道站点开发利益影响范围及相邻站点间影响范围分界线的计算,并能为轨道沿线土地利用开发、交通接驳设施设计以及轨道交通开发利益还原提供技术支持。