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1.
Dianfeng Liu Xuesong Kong Boyuan Zhou Yasi Tian Yaolin Liu Hua Wang 《Transactions in GIS》2019,23(4):688-704
Social connections between villages can represent farmers’ interests and thus benefit participatory rural relocation planning. With rural development, however, these connections will change and may weaken the adaptation of relocation plans to future rural systems. As yet, most studies still use empirical social connections to guide relocation planning, while a few have incorporated predicted connections in the context of rural development into relocation decisions. Meanwhile, spatial optimization approaches have seldom been adopted to solve this geographical decision issue. Accordingly, our study proposes a novel spatial relocation framework that incorporates changed inter‐village social connections under future rural development scenarios. Empirical inter‐village connections and their policy‐induced changes in central China were explored using social network analysis. An integration of particle swarm optimization and geographic information systems was adopted to identify the relocation solutions with maximum inter‐village connections and maximum spatial land use compactness, and to examine how connection changes under different policy scenarios influenced relocation outcomes. The results demonstrate the significance of incorporating policy‐induced social connections into relocation plans, and most importantly, show the negative relations between changed social connections and the migration distance/direction of relocated settlements. Our study is expected to improve the adaptation of relocation plans to future rural development. 相似文献
2.
本文以北京城市交通为例,选取北京城市路网数据,计算城市路网介数中心性,以反映城市各道路路段的通达情况;并利用北京出租车GPS定点数据,计算实际的交通轨迹。传统的路网介数中心性主要依据各路段最短路径的比重评价理论上的道路通达性,而本文以网络介数中心性为基础,提出动态介数的方法,从城市各路段交通量比重的角度评价各道路实际拥堵情况。利用两个介数的对比能够全面客观地反映交通拥堵状况,提高交通拥堵指数的参考价值,并为城市建设规划决策及道路改建等方案提供依据,有利于缓解城市道路交通拥堵现状。 相似文献
3.
Accessibility Futures 总被引：1，自引：0，他引：1
This study uses accessibility as a performance measure to evaluate a matrix of future land use and network scenarios for planning purposes. The concept of accessibility dates to the 1950s, but this type of application to transportation planning is new. Previous research has established the coevolution of transportation and land use, demonstrated the dependence of accessibility on both, and made the case for the use of accessibility measures as a planning tool. This study builds off of these findings by demonstrating the use of accessibility‐based performance measures in the Twin Cities Metropolitan Area. This choice of performance measure also allows for transit and highway networks to be compared side‐by‐side. For roadway modeling, zone‐to‐zone travel time matrix was computed using stochastic user equilibrium (SUE) assignment with travel time feedback to trip distribution. A database of schedules was used on the transit networks to assign transit routes. This travel time data was joined with the land use data from each scenario to obtain the employment, population, and labor accessibility from each traffic analysis zone (TAZ) within specified time ranges. Tables of person‐weighted accessibility were computed for 20 minutes with zone population as the weight for employment accessibility and zone employment as the weight for population and labor accessibility. Maps of accessibility by zone were produced to show the spatial distribution of accessibility across the region. The results show that a scenario where population and employment growth are concentrated in the center of the metropolitan area would produce the highest accessibility no matter which transportation network changes are made. However, another scenario which concentrates population growth in the center of the metropolitan area and shifts employment growth to the periphery consistently outperforms the scenario representing the projected 2030 land use without any growth management strategy. 相似文献
4.
During the last six decades, Kuwait has experienced rapid and unprecedented population growth with only a small increase in the urban areas. The alarming rise in urban density in Kuwait has caused issues for the residents' lifestyles, the economy and the environment. These issues have been aggravated by urban planning which perpetuated a city‐centric urban form without modelling the impacts of current patterns of urban growth. A spatial model using Agent Based Modelling (ABM) and Geographical Information Systems (GIS) is proposed to model disaggregate future changes in land‐use patterns given forecast population estimates and planning policies. The two main impacts considered are housing shortage and traffic congestion, as these are the two most significant social impacts for Kuwaitis. This article discusses the design methodology and parameterization of the ABM and the agent groups. It characterizes urban growth by rules for different citizen groups, historical growth patterns and the influence of decision‐makers. The model is validated against data for the period 1995‐2015 and simulations run to 2050; the results predict that continued city‐centric growth will aggravate the problems, with more than 50% increase in housing shortage and congestion unless the government intervenes to rectify the situation. 相似文献
5.
Evaluating the importance of accessibility to congestion response using a GIS-based travel simulator
Irene Casas 《Journal of Geographical Systems》2003,5(1):109-127
This paper examines the effect of accessibility on individual response to unexpected traffic delays and congestion. The dataset
used was collected by means of a travel simulator developed within a geographic information system (GIS) environment. The
simulator models a commute trip where congestion takes place, and subjects are asked to respond by making a choice among alternative
courses of action. Available alternatives for dealing with the unexpected traffic delay include changing the location of the
planned activities or changing the activities to be performed. Accessibility to the new locations and to the different activities
is computed using a cumulative measure. Analysis using CHAID tree technique found that accessibility is a good predictor of
subjects' choice when responding to unexpected traffic delays.
Received: September 2002 / Accepted: January 2003
Support for this research by a grant from the Center of Intelligent Transportation Research of the Ohio State University
is gratefully acknowledged. The author would also like to thank Joe Weber, Mei-Po Kwan and two anonymous reviewers for their
valuable comments. 相似文献
6.
我国快速城市化进程正在遭受着环境污染、交通拥挤、住房紧张等一系列的城市问题,城市生态环境质量持续下降。城市绿地对城市碳氧平衡的调节具有重要作用,大力发展城市绿化将有助于改善城市环境问题。但目前我国城市绿地建设缺乏具体的空间分布规划,只注重绿地覆盖率和人居绿地面积,绿地服务功能的公平性问题没有得到充分重视。本文利用ArcGIS对大连市沙河口区的绿地可达性进行了研究,通过对比绿地可达性与沙河口区人居环境类型发现,高收入社会群体拥有比低收入社会群体更高的绿地可达性。城市规划者应该注意到这些问题,并在今后的建设中关注社会各阶层对绿地的需要,使城市居民在享受公共服务资源上更为公平。 相似文献
7.
Mapping the spatial disparities in urban health care services using taxi trajectories data 
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下载免费PDF全文 The understanding of spatial inequality in health care services is critical for reasonable policy‐making and management. In this study, we present a novel approach to analyze the demand–supply of health care services using taxi data. Taxi data provide observations of individual travel activities, and hence can be used to characterize the actual demand–supply of health care services. We apply the proposed approach in Guangzhou, China to carry out a case study. The results show the spatial disparities in health care service access. About 21.05% of the total population has high hospital accessibility, while the remaining 78.95% has relatively low hospital accessibility (i.e., roughly an “80/20” distribution). It is found that 6.29% of the population lives in high‐density suburban communities but has relatively low hospital accessibility. Most of the hospitals serve a population that is compatible with their capacity. One hospital is found to have a small capacity but to serve a large population, while two hospitals have relatively high capacities but serve small populations. These findings can help improve our understanding of spatial inequalities in public service provision, and may also provide useful information to address the health care problems of an aging population in contemporary, rapidly urbanizing China. 相似文献
8.
Quantification and assessment of nationwide population access to health-care services is a critical undertaking for improving population health and optimizing the performance of national health systems. Rural–urban unbalance of population access to health-care services is widely involved in most of the nations. This unbalance is also potentially affected by varied weather and road conditions. This study investigates the rural and urban performances of public health system by quantifying the spatiotemporal variations of accessibility and assessing the impacts of potential factors. Australian health-care system is used as a case study for the rural–urban comparison of population accessibility. A nationwide travel time-based modified kernel density two-step floating catchment area (MKD2SFCA) model is utilized to compute accessibility of travel time within 30, 60, 120, and 240 min to all public hospitals, hospitals that provide emergency care, and hospitals that provide surgery service, respectively. Results show that accessibility is varied both temporally and spatially, and the rural–urban unbalance is distinct for different types of hospitals. In Australia, from the perspective of spatial distributions of health-care resources, spatial accessibility to all public hospitals in remote and very remote areas is not lower (and may even higher) than that in major cities, but the accessibility to hospitals that provide emergency and surgery services is much higher in major cities than other areas. From the angle of temporal variation of accessibility to public hospitals, reduction of traffic speed is 1.00–3.57% due to precipitation and heavy rain, but it leads to 18–23% and 31–50% of reduction of accessibility in hot-spot and cold-spot regions, respectively, and the impact is severe in New South Wales, Queensland, and Northern Territory during wet seasons. Spatiotemporal analysis for the variations of accessibility can provide quantitative and accurate evidence for geographically local and dynamic strategies of allocation decision-making of medical resources and optimizing health-care systems both locally and nationally. 相似文献
9.
Pluvial flash flood (PFF) can cause serious traffic disruption in big cities. We conducted interdisciplinary research by integrating flood modeling and traffic analysis to reveal the spatiotemporal pattern of the interplay between these two processes. A simplified simulation tool, which is capable of building a road network model, assigning trip paths with the effect of road closures, and evaluating travel delay and vehicle volume redistribution in a given PFF scenario, was developed to capture the traffic disruption in the face of PFF events. Modeling outputs from a case study in the city center of Shanghai showed that the delay of vehicles diverted to dry links or trapped in flooded links may reach 0.5 to 8 times the travel time in no‐flood scenarios. Overall, approximately 1–7% of vehicle volumes on flooded links would be redistributed onto dry links (more likely major arterial roads). However, the vehicle volume variation during each time interval demonstrated evident disparity with the spatiotemporal change of flood inundations. Simulating and mapping the congestion can largely facilitate the identification of vulnerable links. Future research will test the method in other intra‐urban areas and try to bridge the gap between modeling outputs and smart city planning and management. 相似文献
10.
公共医疗卫生服务的空间可达性研究——以广州市海珠区为例 总被引：9，自引：0，他引：9
本文以第5次人口普查以及医疗卫生机构相关数据为基础,运用空间相互作用理论和模型,得到广州市海珠区各街区的公共医疗卫生服务可达性空间分布,并详细分析了医院等级系数对可达性指数的影响,为医疗卫生事业的发展规划提供辅助决策支持。 相似文献
11.
Diego Bogado Tomasiello Mariana Giannotti Renato Arbex Clodoveu Davis 《Transactions in GIS》2019,23(2):203-223
Vehicle tracking is a spatio‐temporal source of high‐granularity travel time information that can be used for transportation planning. However, it is still a challenge to combine data from heterogeneous sources into a dynamic transport network, while allowing for network modifications over time. This article uses conceptual modeling to develop multi‐temporal transport networks in geographic information systems (GIS) for accessibility studies. The proposed multi‐temporal network enables accessibility studies with different temporal granularities and from any location inside the city, resulting in a flexible tool for transport and urban planning. The implemented network is tested in two case studies that focus on socially excluded people in a large global city, São Paulo, Brazil, including accessibility analyses from slum areas. It explores variations within a day and differences between transport modes across time. Case study results indicate how the accessibility is heterogeneous in low‐income regions. 相似文献
12.
With the rapid development of social economy in Chengdu, it is of great significance to analyze the accessibility of a public facilities resources, and services in respective regions for the spatial planning of public facilities and the optimization of urban construction in Chengdu. Most existing studies only consider the accessibility of a single public facility under a single transportation mode studying facilities at the same level. In this research, with the consideration of all these factors mentioned above, an improved 3-step floating catchment area (3SFCA) model of multi-transportation modes is introduced to analyze the accessibility and spatial distribution of multiple types of public facilities under multiple traffic modes. The new model classifies the grade of public facilities and calculates the service accessibility of public facilities under the driving, public transport, cycling, and walking modes in the five dimensions of education, medical care, commerce, transportation, and leisure in the central urban areas of Chengdu. Through the comparative analysis of multiple models, we found that the improved 3SFCA can more accurately evaluate the accessibility of all dimensions of public facilities in central urban areas of Chengdu. The accessibility of compound public facilities in the central city is excellent. With the gradual expansion to the outward areas, the diversity and accessibility of compound public facilities gradually decreases. Furthermore, the accessibility distribution of public facilities in the study area is not balanced. The accessibility between the central urban areas and the marginal areas differs greatly and the spatial differentiation is substantial. 相似文献
13.
针对青岛市中心城区交通网络建设不完善的问题,研究了该区域路网的综合可达性,并提出了相应的解决方案。基于GIS平台,建立了青岛市中心城区路网模型;选取最小阻抗(时间和距离)、交叉口服务指数、路网密度和路网连通度作为关键评价指标,分别从路网距离关系、路网结构合理性、路网密度和路网发育程度4个方面分析了该区域的路网可达性;在此基础上,建立了青岛市中心城区路网综合评价模型。研究结果表明,该区域的路网以多中心多圈层形式分布,整体可达性良好;西南区域路网密度低,南部外围区域机动性差,南部地区可达性较差,应不断加强该地区的基础设施与路网建设。 相似文献
14.
交通拥堵检测是城市交通管理工作的重点和难点之一,现有的拥堵检测以路段为单位,不利于拥堵时空演变规律信息的提取,且检测内容大多只涉及拥堵程度,缺少对拥堵类型的识别。基于CART（classification and regression tree）分类树算法,提出一种以路段点为检测单元的拥堵点分类检测方法,该方法可根据路段平均行驶速度实时检测拥堵点及其类型。首先,将路段等距离划分后映射为路段点,根据时空维路况异常规则和异常模式,以路段点为单元分析了4种拥堵类型的时空演变模式;其次,在路段路况检测的基础上,提取路段点路况时空序列,根据不同类型的拥堵模式对路况时空序列进行分类标记;然后,选取4种速度指标作为样本属性集合,按照属性集合提取各路段点在各时段的速度,以此作为决策树学习的数据集;最后,基于CART分类树算法,采用交叉验证的方式训练出最优模型,使其达到最佳的泛化能力。与支持向量机（support vector machine, SVM）分类模型进行比较,实验结果表明,该方法在分类检测交通拥堵点时具有较高的正确率和召回率,且分类检测时效性较好。 相似文献
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16.
Ali Mansourian Alex Lubida Petter Pilesjö Ehsan Abdolmajidi Monica Lassi 《地球空间信息科学学报》2013,16(2-3):97-110
There exist major challenges in accelerating the spatial data infrastructure (SDI) planning process in the developing countries as well as advocating for politicians to support the development of SDI, due to the high complexity of SDI, lack of knowledge and experience, and limited insight in the benefits. To address these challenges, a methodology for SDI planning in Tanzania, based on the system dynamics technique and the communities of practice concept, was adopted and applied within a community consisting of experts from stakeholder organizations. The groups gathered to develop an SDI plan, while they shared their knowledge and discussed their ideas that helped their understanding of SDI. By running the system dynamics model, the development of SDI over time could be simulated that gave the planning community an insight about the future effects of today’s plans and decisions. Finally, an optimum model could be developed by refinements and improvements done with the consensus of the SDI stakeholders. This model included the components and policies that are essential for a successful SDI implementation in Tanzania and can be used as a basis for SDI planning and help to gain political support. Lessons learnt from this research were promising regarding the usability of the methodology for SDI planning in comparable countries. 相似文献
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Ashish Dhamaniya 《Journal of the Indian Society of Remote Sensing》2014,42(4):851-858
Present paper focuses on the development of a planning model for upgradation of rural roads keeping Pradhan Mantry Gram Sadak Yoyna (PMGSY) program as the base of this model. Database for the PMGSY roads of Gandevi block of Navasari district in Gujarat state is prepared which includes data like village data, road network & traffic data. Core network is prepared for all the villages under study which can be defined as rural network required for providing ‘basic accesses to all villages. i.e. all villages are connected nearby market centre and essential places from all weather roads. Planning model is classified in two phases. First phase is the network planning and the second phase is upgradation of roads. For the network planning utility values of the villages is calculated by using Delphi technique and on the basis of that alternative routes are decided. For the upgradation of existing roads, Pavement Condition Index (PCI) value of each road is determined and based on these values upgradation of roads are priorities. The rural road network planning methodology for PMGSY roads based on the accessibility concept is presented in this paper and implemented using Geographic Information System (GIS) technology. 相似文献
19.
GIS与Voronoi多边形在医疗服务设施地理可达性分析中的应用 总被引：5，自引：0，他引：5
王远飞 《测绘与空间地理信息》2006,29(3):77-80
地理可达性是研究评价各种服务设施布局及其服务域的重要指标之一,空间距离、交通便捷性、出行成本等是可达性测度的重要因子。由于医疗设施等公共设施通常以服务的公平性和覆盖性为目标,因此可定义居民点到最邻近医院的距离为地理可达性的测度。在此基础上,作者提出了基于GIS与Voronoi多边形的地理可达性计算方法。这一方法不仅将地理可达性分析中的空间点对之间的距离计算简化为空间查询,方便了GIS应用,而且计算的Voronoi多边形在本质上就是最邻近意义上医院的服务域,即服务域内各居民点到该医院的距离就是最邻近距离。此外结合人口分布等属性数据,还可深入分析各医院的服务承载力,本方法为医疗设施等公共服务设施的规划决策提供了重要的工具。 相似文献
20.
Recent advances in accessibility research: Representation,methodology and applications 总被引：22，自引：0，他引：22
Mei-Po Kwan Alan T. Murray Morton E. O'Kelly Michael Tiefelsdorf 《Journal of Geographical Systems》2003,5(1):129-138
In this article we examine recent advances in accessibility research and their implications for future studies. We base our
discussion on three intersecting dimensions that are useful for evaluating the contribution of recent studies: representation,
methodology and applications. Various examples are selected to show that research concerned with representation and methodological
problem solving is often applied to issues of broad concern in policy and planning. It is, however, not clear that the simultaneous
treatment of representation, methodological and application issues has ever been fully worked out. The questions raised in
this article may serve as a foundation for addressing issues pertinent to accurate representation, improved model building,
and more rigorous applications in accessibility research.
Received: 9 December 2002 / Accepted: 10 February 2003 相似文献