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1.
城市交通、土地利用和城市空间结构的相互关系一直是城市地理学、城市规划学和交通地理学研究的核心问题。大容量公共交通、混合型土地开发、宜人的步行环境和高质量的公交服务是公交导向型开发(TOD)模式的主要特点。本文分析了TOD对城市土地利用和城市空间结构的作用机理发现:土地开发强度、土地利用结构以及土地价值是TOD影响城市土地利用的3 个主要方面,而TOD对路网结构、城市规模和城市空间布局的作用进一步影响城市空间结构及其演化。进一步研究发现:大容量公共交通的建设使得城市竞租曲线和开发密度具有多波峰的特点,遵循"随着时间的变化从城市中心向外围递减"的规律。基于中外城市发展背景差异,本文从宏观、中观和微观3 个层面提出建立以大容量公共交通为主轴、以TOD站点为枢纽的轴辐网络状城市空间结构,并提出了TOD站点开发的距离、级差密度、多样性和设计的4Ds原则。 相似文献
2.
Lauren M. Scott 《The Professional geographer》1994,46(3):378-386
Exploratory data analysis (EDA), a data-centered, inductive approach to statistical analysis, provides effective tools for assessing the quality and integrity of GIS attribute data. This research presents selected examples demonstrating EDA distribution analyses, correlational statistics, and proximity analysis. An integrated modular software prototype to operationalize these techniques combines the mapping and display capabilities of ArcView with the statistical functionality of STATA in a MS-Windows multi-tasking, multiple-windowed environment. 相似文献
3.
轨道交通周边土地开发和溢价归公有助于缓解城市财政压力,推动公交都市建设。结合国外实施溢价归公的政策和实践模式,以东莞市为例,在资料收集、政策分析、文本和案例解读的基础上,探讨了中国城市政府在规划和建设轨道交通中,以土地溢价归公反哺轨道交通融资的政策安排和实施效果。结果表明:1)溢价归公的本质是以特定方式实现正外部效应的内部化,由于土地制度和税收体系的差异,欧美地区溢价归公主要依赖多样化的土地税收体系,而中国城市的实践主要借鉴了“轨道+物业”的联合开发模式;2)东莞市溢价归公策略的形成是综合开发规划编制和审批、沿线土地控制和储备、土地发展权转移、土地增值分配等核心环节有效协调的结果;3)东莞轨道交通沿线土地开发能形成可观的财政收益,潜在土地收益占轨道资金总需求的比例超过20%,但在实施过程中仍面临较大困难。东莞市案例能为其他城市轨道交通融资、土地开发和溢价归公的政策体系编制和有效实施提供一定的参考。 相似文献
4.
Summary. The polarizations of shear waves recorded by networks of digital three-component seismometers immediately above small earthquakes near the North Anatolian Fault in Turkey display shear-wave splitting on almost all shear-wave seismograms recorded within the shear-wave window. This splitting is incompatible with source radiation-patterns propagating through simple isotropic structures but is compatible with effective anisotropy of the internal structure of the rock along the ray paths. This paper interprets the phenomena in terms of widespread crack-induced anisotropy. Distributions of stress-induced cracks model many features of the observations, and synthetic polarization diagrams calculated for propagation through simulated cracked rock are similar to the observed patterns. This evidence for widespread crack-induced anisotropy lends strong support to the hypothesis of extensive-dilatancy anisotropy (EDA) suggested by laboratory experiments in subcritical crack-growth. The crucial evidence confirming some form of EDA would be observations of temporal changes in shear-wave splitting as the stress field alters the crack density and crack geometry. There is some weak evidence for such temporal changes at one site, but further analysis of suitable digital three-component seismometer networks in seismic areas is required to confirm EDA. 相似文献
5.
生态示范区建设是我国贯彻可持续发展的重要举措,生态理论、循环经济理论和可持续发展理论是生态示范区建设的基本理论。以甘肃省平凉市国家级生态示范区建设试点为例,从经济发展水平和环境状况方面比较分析、定性评价了平凉市可持续发展的现状水平。在此基础上,从实现可持续发展、发展生态产业和循环经济的可行性的角度,指出平凉市生态示范区建设具有外部支持、有限目标、在生态工业发展中把污染物的过程控制与末端治理结合起来、强化典型农业生态区示范等特殊性。生态示范区建设模式具有地域特色,只有关注地域特色,生态示范区建设才能取得更大成效。 相似文献
6.
自2001-2006年,中国科学院与英国鸟类研究中心联合对新疆准噶尔盆地和昆仑山、青海玉树地区、西藏那曲地区的猎隼(Falco cherrug)分布状况与繁殖生态进行深入调查。考察行程上万公里。卫星跟踪显示在俄罗斯、蒙古繁殖的猎隼迁往青藏高原越冬。但是,实地调查表明,在新-青-藏还有一些繁殖种群;繁殖区的海拔高度从600 m,上升至5 200 m。根据观察,猎隼喜欢沿用旧巢,多数巢属于"垃圾巢"。因为高原缺乏合适的巢材,那些人类遗弃的皮管、铁丝、皮带、破布、汽车零件、骨片、绳子等垃圾充斥于巢穴之中。考察期间,共找到100多只猎隼成鸟、约35个猎隼巢或巢区;分布地点涉及昆仑山脉、准噶尔盆地、卡拉麦里山脉、北塔山、可可西里、唐古拉山脉等,包括新疆奇台、且末、青河、塔城,青海楚玛尔河、五道梁、曲麻莱、雁石坪、玉树,西藏安多、那曲等。猎隼巢址多位于悬崖凹陷处(21个)、河岸砂土洞(5)、桥梁(2)等处;巢高于地面7~30 m。通常沿用渡鸦、大鵟、棕尾鵟、金雕的旧巢,有同步繁殖现象。附近有鼠兔、雪雀、地鸦、岩鸽、石鸡、沙鸡等活动。巢区沿着山脉或者丘陵连续分布,巢间距最近2.5 km,通常4~8 km或更远。在准噶尔盆地其繁殖密度1.1~1.6对/1 000 km2。通常4~5月产卵,窝卵数3~5枚;5月上旬和中旬已有部分幼鸟出壳。虽然在中国捕捉猎隼现象十分猖獗,但考察结果依然令人振奋。建议中国猎隼研究小组(CSRG)积极开展国际合作,通过卫星跟踪、GPS定位、电子微芯片标记(PIT)、DNA指纹图谱分析、人工猎隼栖架和巢穴招引技术等,不断完善监测手段和管理机制,为猎隼的保护与合理利用做出努力。 相似文献
7.
C.WEIHS Mathematical Applications Information Services R-.Z. CIBA-GEIGY Ltd. CH- Basel Switzerland 《地理学报(英文版)》1993,(5)
Exploratory data analysis(EDA)is a toolbox of data manipulation methods for looking at data to seewhat they seem to say,i.e.one tries to let the data speak for themselves.In this way there is hope thatthe data will lead to indications about'models'of relationships not expected a priori.In this respect EDAis a pre-step to confirmatory data analysis which delivers measures of how adequate a model is.In thistutorial the focus is on multivariate exploratory data analysis for quantitative data using linear methodsfor dimension reduction and prediction.Purely graphical multivariate tools such as 3D rotation andscatterplot matrices are discussed after having introduced the univariate and bivariate tools on which theyare based.The main tasks of multivariate exploratory data analysis are identified as'search for structure'by dimension reduction and'model selection'by comparing predictive power.Resampling is used tosupport validity,and variables selection to improve interpretability. 相似文献
8.
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
9.
Tong Zhang Yicong Li Hui Yang Chenrong Cui Jing Li Qinghua Qiao 《International journal of geographical information science》2020,34(6):1137-1161
ABSTRACTEffective public transit planning needs to address realistic travel demands, which can be illustrated by corridors across major residential areas and activity centers. It is vital to identify public transit corridors that contain the most significant transit travel demand patterns. We propose a two-stage approach to discover primary public transit corridors at high spatio-temporal resolutions using massive real-world smart card and bus trajectory data, which manifest rich transit demand patterns over space and time. The first stage was to reconstruct chained trips for individual passengers using multi-source massive public transit data. In the second stage, a shared-flow clustering algorithm was developed to identify public transit corridors based on reconstructed individual transit trips. The proposed approach was evaluated using transit data collected in Shenzhen, China. Experimental results demonstrated that the proposed approach is a practical tool for extracting time-varying corridors for many potential applications, such as transit planning and management. 相似文献
10.
地理综合思维是解决地理问题的基本思维,其概念的界定和结构的明晰关系到地理学领域综合思维应用的规范性,也影响着地理教育领域综合思维培养方向的正确性。论文基于地理综合思维主流的要素综合、时空综合、地方综合三维分类,尝试对细分小类进行组合,形成了6种地理综合思维认知结构模型假说。以高中学生为样本,运用地理综合思维测量量表获得学生的地理综合思维水平数据,采用探索性因子分析和验证性因子分析方法,对地理综合思维的认知结构假说进行检验。结果发现结构假说与数据拟合不够理想。讨论认为要素综合、时空综合、地方综合是地理综合思维外在的形式认知结构,它们表征了地理综合思维全面、系统、动态的思维特征,而体现心理发展本质的地理综合思维内在认知结构有待进一步研究和确立。 相似文献
11.
中国都市圈中运量型轻轨交通的发展问题研究 总被引：6，自引：0，他引：6
从都市圈的空间结构和交通需求的特点分析入手,讨论了中运量型轻轨交通在都市圈公共交通中的地位与作用。结合中国都市圈建设中有关轻轨公共交通发展的问题,指出发展以中运量型轻轨交通为骨干的城市公共交通是中国都市圈交通建设的重要方向,并对中国都市圈以中运量型轻轨交通为骨干的都市圈综合交通体系的规划建设提出了若干建议。 相似文献
12.
城市轨道交通及其沿线土地一体化发展是城市可持续发展的关键问题。提高城市轨道交通可持续性和土地资源配置合理性的关键需掌握轨道交通客流与土地功能之间的依赖关系,而回归分析是研究二者关系的主要方法。既有研究对于土地利用的描述多基于用地面积等概略数据,难以揭示各类属性的用地对客流的影响机理及其空间效应。采用百度地图POI数据以刻画用地信息,提出城市轨道交通车站吸引范围内用地功能的细粒度描述方法,基于全局常参数和局部变参数的回归模型研究车站早高峰出站客流与粗细粒度土地利用的相互依赖关系及其空间效应。针对北京地铁的案例研究表明：车站出站客流与不同功能用地及POI的依赖程度和空间特征存在显著差异。早高峰出站客流更多地受到与就业通勤相关的商业服务业设施用地、公共管理与公共服务用地的影响。在细粒度层面上,出站客流对写字楼和政府机构的依赖性更大,二者显著分布在就业岗位密集的中心城区功能分区和城市核心区。基于细粒度POI的局部变参数模型能较好地识别各类土地利用对车站客流的影响及其空间异质性,案例研究表明车站客流与土地利用的依赖关系是各类属性功能用地影响及其空间效应的叠加。 相似文献
13.
中国与欧洲位于欧亚大陆的东西两端,中欧的贸易畅通是“一带一路”发展的重要内容。当前,中欧经贸联系仍主要通过海运完成,中欧港口航运网络的连通是贸易畅通的保障,因此,研究中欧港口航运网络的发展演变对于认识和保障中欧贸易的畅通具有重要意义。依据近20 a的3个时间断面(1995、2005、2015年）航运数据,构建中国与欧洲各港口航线联系网络,并通过刻画港口航运网络的复杂性特征,揭示不同港口节点可达性变化的空间分异,进而从中转港体系、网络组织结构两方面探讨中欧航运网络的演化特征。研究表明：① 1995年以来,中欧航线联系的港口节点显著增加,网络覆盖范围明显扩大。2005年和2015年网络均表现出明显的小世界特征和无标度特性;不同港口航线联系的广度、深度和可达性变化差异明显,其中84%的港口可达性增强,地中海和阿拉伯海沿岸少数港口可达性减小。② 中欧航运网络的中转港体系由“V”型转变为“U”型,核心中转港出现分化、中转节点逐渐体系化,中转路径趋于多元化,网络稳定性增强。③ 中欧航运网络的轴—辐组织结构不断优化,网络运行效率明显提升,航线联系更加多元化、复杂化。中欧港口航运网络的轴—辐空间结构经历了“三角型”“均衡哑铃型”和“非均衡哑铃型”3个阶段,最终形成以上海港和鹿特丹港为主枢纽的多层次轴—辐空间组织结构。 相似文献
14.
城市轨道交通是大城市缓解交通拥堵的重要公共交通方式,其对周边住宅的时空溢价效应一直是城市研究热点,但传统研究存在样本量少、数据时间跨度短、忽视预期效应等问题。该文利用网络爬虫获取住宅交易大数据,以天津市地铁6号线为例,采用直接比较法、特征价格模型测度城市轨道交通对沿线住宅价格的时空溢价效应,结果表明:1)空间尺度上,轨道交通对沿线住宅价格具有显著溢价效应,但溢价程度并非随着距轨道交通站点距离的增加而下降,而是呈现先上升后下降的“倒U形”趋势。其中,500~1000 m的影响区溢价幅度最大,溢价率高达17.2%。2)时间尺度上,轨道交通对住宅价格的影响具有超前效应,在施工期溢价就已显现,且在首个开通运营年达到峰值,说明住宅价格对开通运营这一“标志性”事件反应强烈。3)受心理预期效应的影响,轨道交通全线开通运营的溢价效应明显低于首个开通运营年的溢价效应。研究结论可为公共交通导向模式下城市综合开发和轨道交通的“溢价回收”策略提供决策支持。 相似文献
15.
The basis for earthquake prediction 总被引：3，自引：0，他引：3
Stuart Crampin 《Geophysical Journal International》1987,91(2):331-347
Summary. Recent advances in understanding the behaviour of shear waves propagating in the crust make the routine prediction of earthquakes seem practicable. Accumulating evidence suggests that most of the Earth's crust is pervaded by distributions of fluid-filled cracks and microcracks that are aligned by the contemporary stress-field so that the cracked rockmass is effectively anisotropic to seismic waves. This causes shear-waves to split, and shear-wave splitting is observed whenever shear-waves propagating along suitable raypaths in the crust are recorded by three-component instruments. These distributions of cracks are known as extensive-dilatancy anisotropy or EDA. Many characteristics of the crack- and stress-geometry can be monitored by analyzing shear-waves propagating through the cracked rockmass. Observations of temporal variations of the behaviour of shear-wave splitting in seismic gaps confirm these hypotheses, and suggest that stress changes before earthquakes may be monitored by analyzing shear-waves. In particular, monitoring earthquake preparation zones with three-component shear-wave vertical-seismic-profiles could lead to techniques for the routine prediction of earthquakes. 相似文献
16.
北京公交就业可达性及其地区和人群差异 总被引：2，自引：0，他引：2
运用经济普查、人口普查数据和基于百度地图的公交出行时间数据,分析北京都市区基于公共交通的就业可达性及其在城市不同人群和地区间的差异。结果表明：北京都市区的居民可在60分钟内通过公共交通到达18.3%的都市区工作岗位,这比美国100个最大的都市区的平均就业可达性水平要高,接近于美国纽约都市区的就业可达性水平。同时,由于就业郊区化程度有限和以中心—放射式布局的公交网络,北京都市区内的公交就业可达性存在着巨大的区域差异,中心城区的就业可达性远远高于郊区。此外,人口居住的郊区化程度远远高于就业的郊区化程度,导致北京都市区宏观层面的职住不平衡。随着人口居住郊区化程度的提高,公共交通如何服务居住日益分散的人口,提高就业可达性,是一项巨大的挑战。研究还发现,由于城市中心区的大部分就业为高技术的就业岗位,因此高受教育程度人口能更多地享受目前公共交通系统的便利,而受教育程度低的人口和外来人口公交就业可达性较低。为解决弱势群体所面临的就业可达性的不平等问题,需要更多的规划与政策干预。 相似文献
17.
The relationship between public transit and crime has been extensively investigated for decades. Compared to rail systems, limited research has been conducted on bus transit and its surrounding robbery influence. In particular, most of the studies have focused on either all types of robbery as a whole or street robbery only. Street and off-street robberies have distinct spatial characteristics, however: The former occurs on the street, whereas the latter occurs not on the street but at indoor places or in (semi)public areas. Therefore, they might have different proximity to bus transit. Furthermore, as bus transit is not operated twenty-four hours a day, it is questionable to connect bus transit with robbery when bus transit is not in service. This study uses exploratory spatial data analysis and statistical modeling to compare and contrast street and off-street robberies to discover how their relations with bus transit vary in space and time. Results reveal that both street and off-street robberies decrease as the distance from bus stops increases. Compared to off-street robbery, street robbery is inclined to occur on the street without bus routes and during nonservice hours, respectively. These findings suggest that the preference of street robbery is related to the excess of suitable targets over capable guardians away from bus routes and when bus transit is not in operation, whereas off-street robbery is connected with the residential and commercial attractions along bus routes and people's frequent activities at these places during transit service hours. 相似文献
18.
19.
Richard Le Heron 《New Zealand geographer》1985,41(2):64-66
This note urges great caution in the uncritical adoption of any 'standard method' in geographical research. Morrison's (Exploratory Data Analysis or EDA) strategy is reminiscent of the technique-driven studies of the 1960s in geography that were heavily criticised within a decade (Morrison 1985, 1983). A case is presented which demonstrates that early reliance on EDA is a risky venture if the objective is an explanatory one. 相似文献
20.
随着中国城市轨道交通的大力发展,城市轨道交通对沿线住宅价格的影响引起广泛关注,探索其时空效应有助于预测未来新建轨道交通的影响以及帮助政府制定合理的房价调控和城市土地利用政策。以福州地铁1号线为例,探讨城市轨道交通从建设前到建成运营的过程中,对站点周边2 km范围内住宅价格产生的时空效应。结果表明：① 城市轨道交通沿线住宅价格受到区位、邻里、建筑等多方面因素的综合作用,其中,城市轨道交通对沿线住宅价格有显著的增值效应,中高价位住宅市场受到城市轨道交通的影响最为明显。② 空间维度上,住宅价格随着与轨道交通距离的增大而呈现不同程度的递减,至轨道交通站点距离每减少1 km,住宅价格增加5.1 %。轨道交通对沿线住宅价格具有显著的分市场效应,中心城区市场的影响半径大于非中心城区市场,平均空间影响范围为1.5 km;而非中心城区市场的影响强度要远高于中心城区市场,在400 m范围内住宅价格受到轨道交通的影响最大。③ 时间维度上,城市轨道交通在建设期和运营期对沿线住宅价格均呈现出正向影响,且运营期对住宅价格的影响显著高于建设期,运营期相较于建设期平均涨幅达19.63 %;同时,轨道交通的开通给住宅价格带来的效应远大于调控政策以及宏观经济因素的影响。 相似文献