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1.
《The Professional geographer》2013,65(3):326-334
The degree to which people judge the change in transit service level as service connectivity changes is assumed to vary with total transfer waiting time. An experiment was devised to collect measures of cognized connectivity of intercity transit services in relation to transfer time, and cognitive scalar values were consequently derived. An inverse relationship was found between cognized service level and connectivity; cognized transit level decreased at a decreasing rate. An analysis of the bus-service network in the Israeli Galilee region suggests the appropriateness of cognitive scalars for measuring the internodal accessibility of public transport services. 相似文献
2.
Tong Zhang Shaoxuan Dong Zhe Zeng Jing Li 《International journal of geographical information science》2018,32(8):1649-1676
The temporal dimensions of public transit accessibility have recently garnered an increasing amount of interest. However, the existing literature on transit accessibility is heavily based on oversimplified assumptions that transit services operate at deterministic speeds using predetermined timetables. These measurements may overestimate transit accessibility, especially for large metropolitan areas where inter- and intra-modal transfers are frequent. To handle travel time uncertainty, a multi-modal transit accessibility modeling approach is proposed to account for realistic variations in travel time and service reliability. The proposed approach is applied to the mapping of transit accessibility in Shenzhen (China), where transit services exhibit significant travel time variations over space and time. Compared to traditional transit accessibility measures, our method has been demonstrated to better capture intrinsic spatial and temporal accessibility variations with complex multi-modal transit networks. Normal distribution of inter-stop travel times and constant travel speed between GPS sampling points are assumed to simply the computation, which we consider to adjust in future studies to better quantify the dynamics of transit accessibility across space and time. 相似文献
3.
This paper examines the integration of landscape connectivity and ecosystem services. It is based on the assumption that if a habitat within a landscape has a more significant role in connecting with other habitats, it would have a higher ecosystem services value for biodiversity conservation. The Shenzhen River watershed, a cross-border region shared by the city of Shenzhen and the Hong Kong Special Administrative Region in China, was used as a case study. An area-based functional connectivity index, known as the possibility of connectivity (PC), was implemented to examine the temporal and spatial dynamics of the value of ecosystem services for biodiversity conservation over the period from 1988 to 2008. To evaluate the effectiveness of the PC index, a comparison was made between the conventional assessment method for ecosystem services and the proposed method. Results suggest that our proposed method can identify significant reduction of ecosystem services that was not only due to the decrease of habitat size, but also caused by the damage of connectivity among habitat patches. Also, it can identify sites which should have a high priority in restoring the ecosystem services for biodiversity conservation. In conclusion, this study provides a way to consider landscape connectivity in the evaluation of ecosystem services which is essential for landscape planning and nature conservation. 相似文献
4.
国际连通是航空枢纽城市内通外联的基本功能体现,利用构建的航空枢纽连通模型测算了我国所有国际通航城市2012年和2017年的国际连通性指数和国际中转指数,并与城市的枢纽定位比较分析。五年间我国航空枢纽城市的国际连通能力快速提升,以北京、上海、广州为代表的三大国际枢纽城市仍主导我国航空运输市场的国际中转连通,但国际连通性指数所占份额在下降,次国际枢纽城市和部分区域枢纽国际连通功能快速提升。洲际长航线对各类枢纽城市国际连通能力的提升更具有网络扩张作用,中短途国际航线对次国际枢纽及区域枢纽的国际连通具有重要意义,基地航空公司对城市的国际枢纽建设有着举足轻重的影响。我国国际枢纽的空间分布从单一的“三点集聚”开始向“多点分化”演化,国际枢纽城市的空间演化契合了我国地区经济开放发展与国际航空运输需求的多样化发展趋势。国际航线网络布局、机场设施发展是建设高质量国际中转枢纽的基础保障,部分新晋枢纽城市缺少有效国际连通与之匹配,“之路”与开放门户等枢纽发展战略仍任重而路远。 相似文献
5.
With the explosive growth of Uber and other mobility service providers, their influences on urban mobility have attracted attention from both researchers and policy circles alike, yet few quantitative studies have been conducted on the topic. Using Uber pickup data in New York City in 2014, this article investigates the spatiotemporal relationship between Uber and public transit using buffer analysis and spatial cross-correlation analysis and assesses Uber’s impact on urban transportation equity with the Gini coefficient and correlation analysis. Our results confirm previous arguments that Uber both complements and competes with public transit, but competition is more prevalent in New York City. Specifically, Uber competes with public transit during most hours of the day and in areas with good public transit coverage, whereas it complements public transit at midnight and in places with insufficient public transit services. The distribution of Uber services is highly unequal, and Uber’s role in improving transport equity is insignificant. Correlation analysis shows that there tend to be fewer Uber pickups in low-income areas, which diverges from previous studies suggesting that Uber serves low-income areas well. In addition, a weak negative correlation is detected between the number of Uber pickups and the percentage of minorities. 相似文献
6.
Land consolidation has a profound impact on landscape patterns and ecological functions at various scales through engineering and biological measures. In recent years, China invests more than 100 billion RMB yuan on land consolidation each year. To understand how land consolidation affects landscape patterns and ecosystems, we investigated the ecosystem service value and the ecological connectivity in a consolidated area of Da’an city from 2008 to 2014 using a revised ecological connectivity index. The results indicated that land consolidation has certain negative influences on the ecosystem services in this area. The total ecosystem service value will decrease by nearly 30% in the late stage of consolidation. This decrease is caused by the loss of ecosystem service of the wetland and grassland, despite a sensible increase of cultivated land. In addition, land consolidation could change the ecological connectivity as well as the land use structure. Up to 85% of the entire area will be in low connectivity in the late stage of consolidation, representing a 6.23% increase in the total coverage compared to pre-consolidation. Finally, the different connectivity landscape and their key areas can be identified by the revised ecological connectivity index effectively. This study is helpful to trace out the relationships between landscape pattern and ecological process, and provides insights for ecological planning and designing of land consolidation in this area. We suggest that more attentions should be paid to improve the quality and ecosystem service value per unit area of the landscape, to establish ecological compensation mechanism of wetland losses, and to create the ecological corridors along the least accumulated impendence surface in the key areas during land consolidation. 相似文献
7.
《Urban geography》2013,34(4):344-364
Inadequate transportation has emerged as a major barrier to employment for welfare recipients required to transition from public assistance to employment under welfare reform. Transportation is a particularly daunting barrier for single women without access to a household car. This study uses multivariate techniques to examine whether nearby transit access impacts the employment outcomes of this population in Los Angeles County. Results show that the level of transit service near a recipient's home makes a moderate, yet statistically significant, contribution to increasing the probability of employment and transit use for work-related trips. However, recipients who use public transit face multiple problems, including overcrowding and infrequent service. 相似文献
8.
运用世界发展指标和国际统计年鉴数据,从时间序列的角度并深入服务业增加值及增长速度、就业比重、就业结构、行业结构、服务业贸易五个方面进行国际比较。结果表明:我国服务业发展水平与整体经济不协调,工业对服务业的支撑能力较弱,服务业的增速高于世界主要国家:服务业的就业比重稳步上升,与世界平均水平差距较大,但吸纳就业的潜力仍然较大;传统服务业比重较高而现代服务业比重偏低,房地产、租赁及商务服务业、社会服务业的就业比重远落后发达国家;服务业出口快速增长,但出口多集中与传统服务业,知识、技术密集型服务业出口偏少。 相似文献
9.
选取2004—2015年天津市生产性服务业和制造业时间序列数据,使用协整分析对二者协同发展关系进行分析,并进一步运用灰色关联分析模型对二者部门间产业关联进行了研究。结果表明:二者之间虽然存在长期均衡和协同发展关系,但也呈现出非均衡性特点,表现为制造业对生产性服务业的带动作用大于生产性服务业对制造业的支撑作用;应通过促进天津市生产性服务业与制造业融合,提升天津市技术服务类等现代生产性服务业的水平,并强化产业间关联,以实现生产性服务业和制造业协同均衡发展。 相似文献
10.
中国城市群核心城市服务业发展的基本特征 总被引：2，自引：2，他引：0
服务业正成为新常态下中国经济发展保持适度增速和迈向中高端水平的强劲动力,城市群核心城市则是中国服务业发展的重要空间载体。本文采用区位熵、对外服务流模型、熵值法,对2003年和2012年中国20个城市群32个核心城市的服务业专业化程度、外向服务功能、综合发展水平等进行分析,结果表明：核心城市服务业地域分工明显,生产性服务业专业化程度较高;核心城市服务业对外服务功能与城市规模等级具有显著相关性,多数属于生产性服务功能主导型,少数属于生活性服务功能主导型以及生产性和生活性服务功能并重型;核心城市服务业内部行业外向功能的空间集中性差异较大,生产性服务业空间集中性普遍高于生活性服务业;核心城市服务业综合发展水平的空间差异显著,与城市群的功能定位较为一致。 相似文献
11.
基于时空路径的城市公交时间可靠性研究 总被引：2，自引：0，他引：2
时间可靠性是公交重要的时空特性之一,提高公交时间可靠性有助于提高公共交通吸引力。基于时间地理学,从时空过程的角度对公交时间可靠性进行了研究。利用公交时空路径,提出一种城市公交时间可靠性的评价方法,该方法包括单程准时度、单程准时稳定度、站点准时度、站点准时稳定度4个指标。然后利用广州公交GPS数据对各指标进行计算。结果表明,公交时间可靠性随着线路长度增大和站点数增加而降低,随着用地类型的不同而变化,其中商业用地内的时间可靠性最大,并且时段不同,可靠性也有较大差异,其中早高峰的时间可靠性最低,从而验证了所提出评价方法的有效性。 相似文献
12.
推动京津冀产业协同发展,要立足于产业关联,推进产业对接协作,在更高层次上实现区域优势互补、联动发展。本文基于北京市、天津市、河北省2007年与2012年的投入产出表,运用MRIO模型,编制了京津冀区域间129部门投入产出表,进而从京津冀地区影响力系数、感应度系数方面分析了京津冀地区生产性服务业产业关联特征。结果表明：①北京市信息服务业、科技服务业,天津市道路运输业、水上运输业对区域经济推动作用较强,河北省生产性服务业对区域经济主要起拉动作用。②北京市科技服务业与天津市信息服务业主要服务于本市其他各行业,对外地经济的辐射作用较低。③京津两市生产性服务业产业趋同现象严重,不利于区域经济的发展。 相似文献
13.
采用城市化综合水平测度模型、生态系统服务价值评价模型及Pearson相关分析方法,在GIS技术支持下,以宁波市1991—2014年城市化相关数据和土地利用变更调查成果为基础数据,定量评价和分析区域城市化发展水平、生态系统服务价值以及二者之间的关系。结果表明:(1)宁波市各项城市化指数均呈逐渐递增趋势,城市化发展进程呈阶段化特征。快速城市化水平驱动区域经济高速发展,同时导致建设用地面积大幅度增加。(2)宁波市生态系统服务价值总体变化呈先增后减趋势,各县(市、区)生态系统服务价值空间分布差异显著,区域城市化水平越高其所贡献的生态系统服务价值越低。(3)当前城市化发展水平与生态系统服务价值演变之间呈显著负相关,经济城市化和土地城市化对生态系统服务功能产生的负面影响较为显著。快速城市化引起区域土地利用的剧烈变化,导致生态景观格局转变,城市人口集聚与工业化导致过度消耗资源与废物排放,对生态系统服务功能产生负面影响。建议提高宁波市城市化发展质量,注重与经济和社会的协同发展。 相似文献
14.
The concept of transit-rich neighborhoods (TRNs) has become a focus of more interest as it relates to rapidly growing and congested communities, and it has received national attention because of its contribution to smart growth in the United States. Although most investment in transit services has been concentrated in denser central cities, where most transit users, including those of low income, reside, the trend toward the decentralization of poverty has become evident in many metropolitan areas and underscored the need to improve suburban transit services. Many studies pertaining to transit ridership have focused on the physical characteristics of stations, their catchment areas, and equity issues for low-income riders, particularly in central cities, without accounting for the evolving socioeconomic characteristics of the neighborhoods being served. To address this issue, this paper categorizes TRNs based on changing socioeconomic and spatial characteristics and uses multiple regression to examine the relationship between types of TRNs and transit ridership in the Atlanta metropolitan area, focusing on the decentralization of poverty. The results show that suburban TRNs became more diverse in terms of income and race between 2000 and 2009, which suggests that investment in commuter rail transit is an important contribution to social and economic equality at the regional level. Furthermore, poverty rates in suburban areas, compared to those in their downtown and inner-city counterpart TRNs, positively influence the percentage of transit ridership. The increased use of suburban transit services suggests the potential presence of increased latent demand, which is further supported by the decentralization of poverty. 相似文献
15.
Producer Services Research in the United Kingdom 总被引：1，自引：0，他引：1
Peter W. Daniels 《The Professional geographer》1995,47(1):82-87
This paper reviews recent research in the United Kingdom on producer services and suggests directions for further research. A recurrent theme in UK-based geographic research into producer services is the role of service activities, establishments, and trade in uneven development of the UK space economy, a role manifested in uneven provision and quality of services in peripheral regions. During the 1980s, overall growth in demand for producer services and the rapid rise in metropolitan London real estate costs reduced London's dominance, but these trends moderated by the end of the decade. In the absence of adequate government statistics, regular and standardized surveys are needed to compile a time series of service change in the United Kingdom. Directions for continued empirical research include the role of producer services in innovation and technology transfer, the implications of information technology for the location of employment in the sector, and the impacts of productivity increases on employment and wages. 相似文献
16.
中国城乡基本公共服务均等化及其空间格局分析 总被引：10，自引：2，他引：8
以中国31个省级行政单位为研究对象,从教育服务、文化服务、医疗卫生服务、基础设施服务、社会保障服务和信息化服务6个方面构建指标体系,综合测度各省份城市和农村基本公共服务水平;利用信息熵原理构建基本公共服务均等化指数,测度各省份城乡基本公共服务均等化程度,并用探索性空间数据分析方法对城乡基本公共服务均等化指数的空间格局进行研究。研究表明：① 各省份城市和农村基本公共服务水平的差异均十分显著。城市基本公共服务水平的空间分布为“T”字型格局,并呈“东—中—西”阶梯状递减;农村基本公共服务水平的空间分布与城市存在很大的不一致性,呈“东—西—中”阶梯状递减的格局。② 31个省份的城乡基本公共服务均等化指数偏低,其空间分布存在着显著的全局空间自相关特征。③ 各省份农村基本公共服务水平对均等化指数的影响大于城市,城乡基本公共服务均等化指数与农村基本公共服务水平的关系类似马太效应。 相似文献
17.
北京市公共文化设施服务水平空间格局和特征 总被引：1，自引：1，他引：0
本文从设施数量、质量、空间分布和满意度4方面,构建设施服务水平综合评价指标体系,借助多指标综合评价法、GIS空间分析和三维模拟技术,探讨北京市中心城区公共文化设施服务水平的空间分布格局和差异特征。由公共文化设施服务水平评价结果得出,不同类型设施服务水平空间差异显著,文化服务中心(文化站)服务水平最高,艺术馆最低。由公共文化服务水平分区可知,54.96%的街道处于低水平。在此基础上总结出其空间特征如下：设施服务水平空间分布不均衡,服务水平整体上呈现明显的“核心—外围”空间结构,沿核心到外围递减,并且核心区较高,西北部和南部地区偏低;服务水平空间分异趋势明显,在东西和南北方向上均呈倒“U”型趋势,并且东西方向相对于南北方向变化较为平缓,由西到东微弱上升;文化设施服务水平空间分布与人口空间分布相关性较弱;文化设施等级与服务水平基本相匹配,高等级设施占比较多的城区设施服务水平也较高。 相似文献
18.
信息技术对服务业创新影响的空间计量分析 总被引：5，自引：2，他引：3
信息技术成为服务业创新的关键因素,并受到国内外学术界的普遍关注,但鲜有从省域及市域层面探索信息技术对服务业创新影响的研究成果。以广东省地级市(域) 为例,运用因子分析、探索性空间数据分析、空间计量模型等实证研究方法,深入分析信息技术和服务业创新的空间分布特征和两者之间的关系。结果表明,服务业创新和信息技术均存在空间正相关性,形成全域空间的核心—边缘模式和局域空间的"俱乐部"模式。高值簇集聚区(珠三角) 的扩散效应只局限在局域"俱乐部"里面,而低值簇亦形成集聚区(粤北、粤东和粤西),体现出珠三角同东西两翼与粤北山区之间巨大的差距。在空间差异和扩散效应的影响下,信息技术和服务业创新在空间上均出现"俱乐部"内趋同、"俱乐部"间趋异的现象。空间计量回归表明,服务业创新在市域空间上具有相互促进作用,信息技术对服务业创新具有明显的促进作用,当信息技术水平每提高1%,服务业创新水平就将提高0.7158%,证明了信息技术是影响服务业创新的重要因素。 相似文献
19.
中国沿海地区生产性服务业发展态势及驱动因素分析 总被引：2，自引：1，他引：1
基于核密度估计、锡尔指数方法,对2005~2015年中国沿海地区生产性服务业发展现状进行分析,运用分位数回归方法探究驱动因素。研究表明：① 2005~2015年沿海地区生产性服务业发展水平持续上升,呈“双峰”分布态势。② 生产性服务业总体差异逐年增大,区域内差异是导致总体差异增大的决定性原因。③ 整体来看,各驱动因素能有效地促进沿海地区生产性服务业发展。国有化程度与生产性服务业呈正相关关系;技术水平对生产性服务业的推动作用远高于其它驱动因素;制造业水平、信息水平及政府作用对生产性服务业的拉动效应相对较弱;人力资本对生产性服务业的作用有待提高;基础设施不能满足生产性服务业发展的需求。 相似文献
20.
Noga Collins-Kreiner 《The Professional geographer》2013,65(4):589-591
This article explores the conceptual and empirical relationships among connectivity, employment, and specialization in advanced business services (ABS) in major cities in the United States. Correlation and regression analysis produces three chief empirical conclusions: First, the distribution of employment predicts and explains the level of connectivity; second, specialization does not predict connectivity; and, closer examination shows that these results vary by sector, which might relate to the informational characteristics of different types of ABS agglomerations. These conclusions demonstrate the continued relevance of agglomerative dynamics as they influence the networks and hierarchies of the ABS and corporate spatial structures. 相似文献