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11.
城市医疗设施空间分布合理性评估   总被引:1,自引:0,他引:1  
随着经济发展和人民生活水平的不断提高,城市居民对健康的重视程度不断的增加,医疗设施作为城市中不可或缺的公共设施发挥着越来越重要的作用。城市的不断扩张导致医疗机构的分布已不能适应当前的城市规模,如何能够将有限的医疗资源进行合理的分配,并能在最大程度上满足居民的需求成为当下研究热点。本研究基于地理信息系统(GIS)空间分析技术,根据统计资料建立武汉市中心城区交通网络、医疗机构分布、人口等数据库,分别从可达性和公平性角度评价武汉市医疗设施的空间分布合理性,并利用地理空间可达性评估法和基于交通网络行进时间成本法分别对武汉市中心城区医疗设施可达性进行评价。就医可达性评估显示,武汉市居民就医便捷程度总体上较好,并以长江和汉江的交界地区为中心,呈四周放射状分布。通过引入需求指数、医疗机构规模、区域人口、人均可支配收入等指标,利用基尼系数、空间相关性和空间分层异质性评价医疗服务设施空间分布公平性。结果表明,武汉市医疗机构分布按人口分布合理,医疗机构主要集中分布在人口密集的主城区;地理分布上城郊地区医疗机构相对稀少。最后,依据可达性和公平性评价结果,对武汉市医疗设施布局提出合理化建议。在城市规划发展中,应更多考虑改善郊区等交通欠发达区域居民的就医条件,从而完善城市医疗设施分布。  相似文献   
12.
高鹏  何丹  宁越敏  韩明珑 《地理研究》2021,40(10):2760-2799
基于2003—2018年企业股权关联投资数据,融合社会网络分析、马尔可夫链分析和空间计量方法,从全球、全国和区域尺度探析长三角地区城市投资联系水平的时空动态特征及影响因素。研究发现:① 长三角地区各尺度的城际投资规模大幅提升,与关境外地区、关境内地区和长三角区域内的投资联系分别呈现服务业驱动型、制造业驱动型和行业均衡型特征。② 各尺度城市投资网络呈现区域指向性和多中心演化特征,上海、杭州、南京等在长三角地区逐渐发挥对外辐合全球和全国投资、对长三角地区内部辐射区域的作用。③ 与关境外、关境内和区域内的城市投资联系水平空间分布不均,以沪宁合杭甬发展廊道为支撑的空间结构逐渐凸显,并分别呈现低水平区集中连片分布、改善空间先沿海后内陆扩张、中低水平区广域化扩张的突出特征。④ 城市投资联系水平整体呈现向邻近较高水平方向转移态势,很难实现跨越式转移,存在显著的俱乐部趋同效应和马太效应。随着空间尺度的扩大,向较高水平方向转移的难度随之增大,俱乐部趋同效应和马太效应也随之增强。地理空间格局在各尺度的城市投资联系水平状态转移中发挥着重要作用,发展水平较高和较低的城市对周边城市分别产生正向和负向的空间溢出效应。⑤ 产业基础、劳动力成本、城市行政级别对各尺度的城市投资联系水平均有显著影响,创新能力对各尺度的城市投资联系水平均未产生显著影响,时间距离对全球和全国尺度的城市投资联系水平影响显著,经济全球化仅对全球尺度的城市投资联系水平产生显著影响。  相似文献   
13.
《Climate Policy》2013,13(3):298-316
The impacts of predicted climate change will not be distributed evenly around the world. As post-Kyoto negotiations unfold, relating the geographical distribution of projected impacts to responsibility for emissions among world regions is essential for achieving an equitable path forward. This article surveys the current knowledge of regional climate consequences, and delves into the regional predictions of economic assessment models to date, examining how the uncertainties, assumptions and ethical dimensions influence the portrayal of risk at this scale. The few studies that quantitatively compared regional risk and responsibility are reviewed, and the analytical framework from one such study is applied to the 2006 Stern Review's projections to give the first regional comparison to take purchasing power and welfare considerations into account. Synthesizing burden and blame in this way is informative for policy makers; the world's most vulnerable communities—in Africa, the Indian subcontinent, Latin America, and small island states—accounted for less than 33% of global greenhouse gas emissions over the period 1961–2000, but may experience more than 75% of the ensuing climate damages this century. This analysis reinforces the call for industrialized nations to lead mitigation efforts, and to do so decisively and swiftly.  相似文献   
14.
Abstract

Environmental justice laws protect certain populations against discriminatory actions that may result from a myriad of enterprises, including transportation activities. Previous environmental equity studies examining the effects of transportation-engendered externalities have been criticized on several points, including (1) that the choice of a reference population for comparison to the criterion variable may influence the outcome of research results and (2) that the selection and use of inappropriate methodologies intended to identify and characterize populations may foreordain research outcomes. This article examines the potentially confounding effects of selected spatial scale and population assignment strategies as applied to a study of excessive noise levels at a large Midwestern airport, finding that reported outcomes can vary significantly as a function of methodological choices.  相似文献   
15.
Global climate negotiations have been characterized by a divide between developed and developing nations – a split which has served as a persistent barrier to international agreement within the United Nations Framework Convention on Climate Change process. Notable progress in bridging this division was achieved at the 21st Conference of the Parties meeting in Paris through the introduction of Intended Nationally Determined Contributions (INDCs). However, the collective ambition of submitted INDCs falls short of a global 2°C target, requiring an effective ratchet mechanism to review and increase national commitments. Inequitable distribution of additional responsibilities risks re-opening historic divisions between parties. This article presents a flexible ratchet framework which shares mitigation commitments on the basis of per capita equity in line with emerging requirements for a 2°C target. The framework has been designed through convergence between developed and developing nations; developed nation targets are based on an agreed standardized percentage reduction wherever emissions are above per capita equity; developing nations are required to peak emissions at or below per capita equity levels by an agreed convergence date. The proposed framework has the flexibility to be integrated with current INDCs and to evolve in line with shifting estimates of climate sensitivity.

Policy relevance

The outcome of the 21st Conference of the Parties (COP21) negotiations in Paris offered mixed results in terms of level of ambition and submitted national commitments. A global agreement to keep average global temperature rise below two degrees was maintained; however, current pledged Intended Nationally Determined Contributions (INDCs) are projected to result in an average warming of close to three degrees. The implementation of a global ratchet mechanism to scale-up national commitments will remain key to closing this ambition gap to reach this two degree target. How this upscaling of responsibility is shared between parties will be a defining discussion point within future negotiations. This study presents a standardized, equity-based framework for how this ratchet mechanism can be implemented – a framework designed to be flexible for evolution in line with better understanding of climate sensitivity, and adaptable for integrations with current INDC proposals.  相似文献   
16.
Over 40 studies that analyse future GHG emissions allowances or reduction targets for different regions based on a wide range of effort-sharing approaches and long-term concentration stabilization levels are compared. This updates previous work undertaken for the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Regional reduction targets differ significantly for each effort-sharing approach. For example, in the Organisation for Economic Co-operation and Development (OECD) 1990 region, new proposals that emphasize the equity principles of responsibility, capability, and need, and those based on equal cumulative per capita emissions (carbon budgets), lead to relatively stringent emissions reduction targets. In order to reach a low concentration stabilization level of 450?ppm CO2e, the allowances under all effort sharing approaches in OECD1990 for 2030 would be approximately half of the emissions of 2010 with a large range, roughly two-thirds in the Economies in Transition (EIT), roughly at the 2010 emissions level or slightly below in Asia, slightly above the 2010 level in the Middle East and Africa and well below the 2010 level in Latin America. For 2050, allowances in OECD1990 and EIT would be a fraction of today's emissions, approximately half of 2010 emission levels in Asia, and possibly less than half of the 2010 level in Latin America.

Policy relevance

The concept of equity and the stringency of future national GHG reduction targets are at the heart of the current debate on the new international climate change agreement to be adopted in 2015. Policy insights gained from an analysis of over 40 studies, which have quantitatively analysed the proposed GHG reduction targets, are presented. It is found that the outcome of effort-sharing approaches is often largely determined by the way the equity principle is implemented and that the distributional impacts of such approaches can be significantly different depending on the criteria used, the stabilization level and shape of the global emissions pathway. However, the current literature only covers a small proportion of the possible allocation approaches. There should thus be an in-depth modelling comparison to ensure consistency and comparability of results and inform decision making regarding the reduction of GHG emissions.  相似文献   
17.
代内公平、国际贸易与可持续发展   总被引:5,自引:0,他引:5  
现阶段,不同国家或区域之间商品交流的种类与数量日益增大。由于发达国家与发展中国家在国际贸易中所扮演的角色不同,因此,在等经济价值交换规律的作用下,发展中国家的环境状况逐渐恶化。文章通过构建开放经济的物质流模型,探讨了物质交换行为对系统内部的自然环境的影响,并对1987年日本的物质流动状况进行了案例研究。分析表明,发达国家的经济发展水平在很大程度上依赖于其它国家内部自然资源与环境的支撑作用。  相似文献   
18.
田玲玲  张晋  王法辉  李响  郑文升  罗静 《地理科学》2019,39(9):1455-1463
公共服务资源的空间配置问题一直存在效率与公平价值导向的博弈,空间综合人文社科的兴起,使其演化成一个空间优化问题。医疗资源空间配置的规划注重决策连续性,据此提出改进空间可达性的两步优化法。在农村地区资源有限的情况下,以空间可达性为主要指标,建立公平与效率导向下的二次规划模型,通过重新选址和设定规模以保证居民获得就医机会的最大公平和效率,并以湖北省仙桃市为案例进行应用研究。结果表明,新选地址和规模优化结果能使仙桃市医疗资源空间配置的公平性和效率性得到显著提高,2个步骤相结合,使其成为真正的混合优化模型,达到效率和公平平衡的双重目标。  相似文献   
19.
This study examines the spatial distribution and impact of nonroutine accidental releases of hazardous materials relative to the demographic composition of residents in nearby communities. First, atmospheric dispersion modeling methods are used to delineate the impact zones of worst‐case accidents in two New York counties over the last ten years. Next, using accidental reports for 1997, GIS and statistical operations are used at the census tract level of the two counties to determine whether these incidents disproportionately affected disadvantaged neighborhoods. The results suggest that the areas of high‐impact from accidental releases of hazardous materials are best characterized by a large proportion of families below the poverty line, Hispanics, and other minorities.  相似文献   
20.
高雅妮  何丹  高鹏  孙志晶 《地理研究》2022,41(6):1577-1592
如何更为精准地刻画流空间视角下城市网络节点地位,是城市网络研究的关注重点之一。本文以长三角地区县级空间单元为研究区域,采用全行业500强上市公司的“母-子-孙”三层级股权关系数据,构建有向加权网络来刻画长三角地区城市间投资联系水平;通过转变中心性与转变控制力对节点城市的网络地位进行分类;最后采用空间计量模型对长三角城市网络节点地位的影响因素进行测算和分析。研究发现:① 长三角城市网络节点地位呈现出“等级+网络”的特征。城市在网络中依旧呈等级分布;然而部分中小城市在网络中地位具有了上升通道,往往可利用资源禀赋使得其获得更高的网络地位,网络结构具有扁平化特征。② 长三角城市网络节点地位特征并没有完全遵循转变中心性与转变控制力的“高-高”“中-中”和“低-低”的匹配关系,而存在“高-中(低)”“中-高(低)”或“低-高(中)”的非匹配关系。③ 城市经济发展水平、人力资本、创新活力、产业结构、城市经营环境和公共服务设施配套情况等会对城市网络地位产生显著的影响。  相似文献   
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