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1.
武汉城市圈城乡道路网的空间结构复杂性   总被引:6,自引:1,他引:5  
以武汉城市圈为研究区,借助ArcGIS9.3、Pajek2.7和SPSS16.0等软件,从节点重要性、可达性、集聚性3个方面定量揭示了复杂城乡道路网的空间异质性:①高度节点重要性呈幂律分布,表现出无标度性,低度节点重要性则基本呈钟型泊松分布,呈现一定的随机性,导致整个圈域节点的重要性分布曲线既不遵循钟型泊松分布也不遵循幂律分布,出现"涌现"性;节点度值空间分布较均匀,呈现点状特征和弱集聚性,具有明显间断性和跳跃性,表现出一定的"中心-边缘"和"等级圈层"的复合结构;②节点的可达性主要由网络平均路径长度、紧密度和介数指标表达,其中道路网平均路径长度较大,节点交通联系呈线状组织,遵循距离衰减律,成等级圈层分异,但受快速干道影响明显,空间收敛减慢,发生"摄动"变形,形成两条以南北京珠高速和东西宜黄高速为轴的城市交通走廊;节点的紧密度系数较随机网络小,但高紧密度节点在空间分布上较为集中,呈现出一定的"中心-边缘"空间格局;节点的介数指标相对较高,呈现指数分布,空间分布较均匀,但仍呈现出一定的"等级圈层"分异;③网络的集聚性空间差异显著,形成多个大型网络社团,网络的聚类系数近似为零,局部呈现耦合性质,高聚类系数节点集聚成"半月形"展布,低聚类系数节点分布较为离散。  相似文献   

2.
Traffic congestion, a common and complicated phenomenon in urban transportation systems, is attracting increasing attention from researchers in Geographical Information Science (GIS) and other fields. In this study, we illustrate a general mechanism that reveals the relationship between travel time and dynamic traffic conditions. We measure a vehicle’s travel time to its destination along any path, where the travel time is calculated based on the path length and on the real-time traffic volume and transport capacity of each road segment on the path. On the basis of this measurement, we present a simple dynamic routing strategy that allows each vehicle to dynamically choose the path to its destination while imposing the minimum travel time. The application of our routing algorithm to the Chengdu street network, Barabási–Albert scale-free network and Erdös–Rényi random network shows that the proposed strategy remarkably improves network throughput and balances traffic load distribution. Our findings suggest that mining the time mechanism of network transport is important to explore efficient time-optimization routing algorithms to enhance the transport capacity of urban street networks and other kinds of networks.  相似文献   

3.
An in-depth analysis of the urban road network structure plays an essential role in understanding the distribution of urban functional area. To concentrate topologically densely connected road segments, communities of urban roads provide a new perspective to study the structure of the network. In this study, based on OpenStreetMap (OSM) roads and points-of-interest (POI) data, we employ the Infomap community detection algorithm to identify the hierarchical community in city roads and explore the shaping role roads play in urban space and their relation with the distribution of urban functional areas. The results demonstrate that the distribution of communities at different levels in Guangzhou, China reflects the urban spatial relation between the suburbs and urban centers and within urban centers. Moreover, the study explored the functional area characteristics at the community scale and identified the distribution of various functional areas. Owing to the structure information contained in the identification process, the detected community can be used as a basic unit in other urban studies. In general, with the community-based network, this study proposes a novel method of combining city roads with urban space and functional zones, providing necessary data support and academic guidance for government and urban planners.  相似文献   

4.
城市道路数据的完整性和实时性是保障位置服务和规划导航路径的关键支撑。该文提出一种基于共享单车轨迹数据的新增自行车骑行道路自动检测和更新方法:首先,结合缓冲区方法和轨迹—路网几何特征检测增量轨迹;其次,基于分段—聚类—聚合策略提取更新路段,利用多特征融合密度聚类算法与最小外包矩形骨架线法提取增量道路中心线;最后,基于拓扑规则完成道路更新。以广州市共享单车轨迹为例,将该方法与传统栅格细化法进行实验对比,结果表明:该方法能有效更新道路网络,且在2 m和5 m精细尺度范围内提取的新增道路覆盖精度提升14%左右;在7 m尺度下精度达90%以上,在10 m尺度下精度达96%以上。  相似文献   

5.
城市复杂道路网的Stroke生成方法   总被引:2,自引:0,他引:2  
传统连接stroke的方法在处理表达较为详细的城市道路网数据时,会产生双行道分离和环岛处截断等错误.为能够在城市复杂道路网中正确生成stroke,针对道路网中的双行道和道路交叉口模式提出一种新的stroke生成方法.该方法采用道路街区几何形态分析、基于连通关系的层次聚类等算法自动识别出道路网中的双行道和道路交叉口模式,并使用穷举stroke配对组合算法连接截断的stroke,从而保证stroke的连续性.以武汉市NAVIN-FOTM导航电子地图数据为例验证该方法的实用性,生成的stroke符合stroke感知归组原则中平滑连贯的要求.  相似文献   

6.
ABSTRACT

Online mapping providers offer unprecedented access to spatial data and analytical tools; however, the number of analytical queries that can be requested is usually limited. As such, Volunteered Geographic Information (VGI) services offer a viable alternative, provided that the quality of the underlying spatialtheir data is adequate. In this paper, we evaluate the agreement in travel impedance between estimates from MapQuest Open, which embraces OpenStreetMap (OSM) data–a is based on VGI datasetfrom OpenStreetMap (OSM), and estimates from two other popular commercial providers, namely Google Maps? and ArcGIS? Online. Our framework is articulated around three components, which simulates potentialcalculates shortest routes, estimates their travel impedance using a routing service Application Program Interface (API), and extracts the average number of contributors for each route. We develop an experimental setup with a simulated dataset for the state of North Carolina. Our results suggest a strong correlation of travel impedance among all three road network providers. and that travel impedanceThe agreement is the greatest in areas with a denser road network and the smallest for routes of shorter distances. Most importantly, tTravel estimates from MapQuest Open are nearly identical to both commercial providers when the average number of OSM contributors along the route is larger. The latter finding contributes to a growing body of literature on Linus’s law, recognizing that a larger group of contributors holds the potential to validate and correct inherent errors to the source dataset.  相似文献   

7.
In this paper, we propose a method for predicting the distributions of people’s trajectories on the road network throughout a city. Specifically, we predict the number of people who will move from one area to another, their probable trajectories, and the corresponding likelihoods of those trajectories in the near future, such as within an hour. With this prediction, we will identify the hot road segments where potential traffic jams might occur and reveal the formation of those traffic jams. Accurate predictions of human trajectories at a city level in real time is challenging due to the uncertainty of people’s spatial and temporal mobility patterns, the complexity of a city level’s road network, and the scale of the data. To address these challenges, this paper proposes a method which includes several major components: (1) a model for predicting movements between neighboring areas, which combines both latent and explicit features that may influence the movements; (2) different methods to estimate corresponding flow trajectory distributions in the road network; (3) a MapReduce-based distributed algorithm to simulate large-scale trajectory distributions under real-time constraints. We conducted two case studies with taxi data collected from Beijing and New York City and systematically evaluated our method.  相似文献   

8.
在ArcGIS软件支持下,构建福州交通网络数据库,并结合多种数据和多种分析方法对福州地铁1、2号线路的交通进行了可达性评价.首先通过ArcGIS中的叠加分析、缓冲区分析、建模等手段对地铁沿线的道路网分布现状进行研究,发现地铁1、2号线建成后将大大缩短通行时间,提高了城市外围地区的交通可达性.其次,利用网络分析工具计算得出地铁将平均减少市民出行时间8.88min,减少地铁沿线出行时间11.6min,在出行高峰期的影响更为显著,可减少将近20min.研究结果可为交通部门提供参考.  相似文献   

9.
陈晓萍  周素红  李秋萍  詹文 《地理研究》2021,40(6):1652-1666
社会空间分异是人文地理学研究的重要议题,以往研究主要聚焦基于居住地和活动地的分异现象,缺乏对道路网社会空间分异的关注。本文以广州市中心区域为例,结合日常活动空间理论和空间分析方法,基于手机轨迹大数据,研究不同性别群体日常出行的城市道路网社会空间分异现象及其影响因素。结果显示:基于性别差异的城市道路网社会隔离指数高于居住地、低于就业地,在14:00—15:00时段达到峰值;不同性别群体在路网中的分布总体呈现不均衡的集聚特点,其中女性集聚程度更高;不同性别群体的出行分布和分异受到路网周边建成环境因素的影响;物流运输业就业密度的提高、小学数量的增多或道路等级的提高都会显著提高男性相对出行量,而社会服务业就业密度的提高、菜市场数量或公交站点数量的增多以及到市中心距离的减少都会显著提高女性相对出行量,这些与个体家庭和职业分工的性别差异有一定的关系。本文通过理论假设和实证分析,验证了家庭和职业的分工决策是影响道路网出行分布性别分异的深层次原因,也是解释社会空间分异的重要理论视角。研究结果有助于认识和挖掘基于城市道路网的社会分异现象及其影响机制,并为完善道路网络及周围设施的布局与建设提供借鉴。  相似文献   

10.
Pedestrian navigation at night should differ from daytime navigation due to the psychological safety needs of pedestrians. For example, pedestrians may prefer better-illuminated walking environments, shorter travel distances, and greater numbers of pedestrian companions. Route selection at night is therefore a multi-objective optimization problem. However, multi-objective optimization problems are commonly solved by combining multiple objectives into a single weighted-sum objective function. This study extends the artificial bee colony (ABC) algorithm by modifying several strategies, including the representation of the solutions, the limited neighborhood search, and the Pareto front approximation method. The extended algorithm can be used to generate an optimal route set for pedestrians at night that considers travel distance, the illumination of the walking environment, and the number of pedestrian companions. We compare the proposed algorithm with the well-known Dijkstra shortest-path algorithm and discuss the stability, diversity, and dynamics of the generated solutions. Experiments within a study area confirm the effectiveness of the improved algorithm. This algorithm can also be applied to solving other multi-objective optimization problems.  相似文献   

11.
随着移动通信与LBS的蓬勃发展,能够描述个体行为的众源时空大数据大量涌现,为感知群体时空行为模式与探究个性化路线提供了新视角。该文将众源时空信息与出行者的个人意愿映射到实际路网空间,融合大众偏好和定制趋势,构建包含主题序列生成、POI推荐、历史路线推荐的局部路网模型,进而实现一种利用众源时空数据改进的HMM路线规划方法,为用户提供合适且个性化的出行方案;以长沙市岳麓区为研究案例,利用真实路网数据与相关兴趣点作为实验数据,基于该方法可在短时间内提供满足用户需求的不同月份的最优路线。  相似文献   

12.
Lane-based road network information, such as lane geometry, destination, lane changing, and turning information, is important in vehicle navigation, driving assistance system, and autonomous driving. Such information, when available, is mainly input manually. However, manual methods for creating and updating data are not only costly but also time-consuming, labor-intensive, and prone to long delays. This paper proposes a hierarchical polygonization method for automatic generation and updating of lane-level road network data for navigation from a road marking database that is managed by government transport department created by digitizing or extraction from aerial images. The proposed method extends the hierarchy of a road structure from ‘road–carriageway–lane’ to ‘road–carriageway–lane–basic lane’. Basic lane polygons are constructed from longitudinal road markings, and their associated navigational attributes, such as turning information and speed limit, are obtained from transverse road markings by a feature-in-polygon overlay approach. A hierarchical road network model and detailed algorithms are also illustrated in this paper. The proposed method can accelerate the process of generating and updating lane-level navigation information and can be an important component of a road marking information system for road management.  相似文献   

13.
We propose a grounded ontological theory of channel networks to categorize features, such as junctions, in road network databases. The theory is grounded, because its primitives can be given an unambiguous interpretation into directly observable qualities of physical road networks, such as supported movements and their medium, connectedness of such media, and turnoff restrictions. The theory provides a very general approach to automatically annotate and integrate road network data from heterogeneous sources, because it rests on application-independent observation principles. We suggest that road network categories such as junctions and roads are based on locomotion affordances. Road network databases can be mapped into our channel network theory, so that instances of roads and junctions can be automatically categorized or checked for consistency by what they afford. In this paper, we introduce affordance-based definitions of a road network and a junction, and show that the definition of latter is satisfied by some of the most common junction types.  相似文献   

14.
以闽江上游地区为例,在传统指数的基础上,提出并采用改进后的道路网络线密度和道路网络影响域面密度指数,结合空间自相关分析方法,从线上和面上综合探索道路网络对生态干扰的空间分异格局;并分析指数间的相关性。结果表明:① 道路干扰程度具有明显的地区差异,在研究区中部、东部和南部存在空间集聚效应;② 考虑到坡度影响,同等级的道路缓冲带宽度并不是一个固定值;③ 所有指数均呈显著正相关,同类指数相关性大,不同类指数相关性小。若仅采用单一的线密度或面密度指数,则将导致信息不全;虽然同类指数间相关性很大,相互印证,但改进后的指数更加符合客观事实,建议采用。  相似文献   

15.
Abstract

Visual interpretation of high-resolution satellite data has been useful for mapping linear features, such as roads and updating land-use changes. However, it would be beneficial to map new road networks digitally from satellite data to update digital databases using semi-automated techniques. In this paper, an algorithm called Gradient Direction Profile Analysis (GDPA) is used to extract road networks digitally from SPOT High Resolution Visible (HRV) panchromatic data. The roads generated are compared with a visual interpretation of the SPOT HRV multispectral and panchromatic data. The technique is most effective in areas where road development is relatively recent. This is due to the spectral consistency of new road networks. As new road networks are those of most interest to the land manager, this is a useful technique for updating digital road network files within a geographical information system of urban areas.  相似文献   

16.
城市道路网络的小世界特征研究   总被引:8,自引:0,他引:8  
小世界模型为研究城市道路网络的拓扑结构和内在特征等提供了新的视角和方法。该文采用原始法(primalapproach)对城市道路网络进行适度抽象,利用ArcGIS 9.0和Matlab 7.0分别处理和计算城市道路网络的空间数据和属性数据,进而探索其小世界特征。以无锡市新区为例,研究该区整体城市道路网络的小世界特征,选取特征各异的局部网络,并对其小世界特征进行比较分析。结果表明,无锡市新区城市道路网络具有较小的特征路径长度和较大的聚类系数,为典型的小世界网络;局部道路网络均具有小世界特征,其显著程度与道路网络的空间结构特征具有一定相关性;疏密适宜的道路网络具有突出的小世界特征,是规划布局的可行方向,可为城市道路网络优化提供指导。  相似文献   

17.
基于手机基站数据的城市交通流量模拟   总被引:4,自引:1,他引:3  
吴健生  黄力  刘瑜  彭建  李卫锋  高松  康朝贵 《地理学报》2012,67(12):1657-1665
基于移动定位数据的城市内社会经济活动特征分析是人类移动性的重要研究内容,而交通流量更是这些特征的基本反映。为还原城市道路网络的使用情况并分析其分布特征,本文从产生交通流量的个体出发,对包含基站位置的手机话单数据进行系统抽样,利用蒙特卡洛方法产生个体的出行起止点,并结合当地道路交通网络求得最短路径,最后估算出一天内道路交通网络上的流量分布。通过分析发现:城市内大部分道路的流量小,使用率低,大部分交通流量集中在小部分主干道路;进一步统计分析可知,当地道路交通流量符合20/80规律,即大约20%的道路承担着80%的交通流量;而对不同类型的道路,流量分布也反映出其在城市道路网络中的地位和作用。此研究对于历史交通流量分布的重现、城市道路交通模式的研究以及基于此的道路网络规划情景模拟都有着重要意义。  相似文献   

18.
以福建省公路交通情况为基本资料,通过运用ArcGIS的网络分析功能,从时间距离的角度,采用加权平均旅行时间的指标,对福建省公路交通网络体系的可达性情况进行计算、分析,得出福建省公路交通网络体系可达性的区域等级情况,在此基础上分别对第一、二、三阶梯的可达性成因进行分析,并对福建省不同地区的交通可达性进行了比较.  相似文献   

19.
研究城市不同要素空间集聚水平与层级差异、明确城市各职能中心分布,对城市多中心空间结构的发展引导和规划调控具有重要意义。论文分别采用兴趣点(points of interest, POI)、夜间灯光和路网3种数据,利用局部等值线树算法,识别武汉市多中心空间结构。研究表明:① 武汉不同城市要素的总体集聚水平不均衡,其中在汉阳集聚水平较低,在汉口和武昌集聚水平较高,特别是二环以内区域;② 武汉中央活动区发展比较均衡,内部各城市要素高度集聚,随着向外扩展,部分城市要素易于在局部集聚形成城市中心;③ 结合武汉圈层发展布局,城市中心沿环线的“商-住-工”职能分布模式逐步确立,其中内环以及二环区域已形成稳定的商服中心;二环附近综合组团内部出现了较具代表性的居住中心;三环外的沌口和武钢主导发展工业,是典型的工业中心。  相似文献   

20.
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