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881.
无人机正处于技术快速突破与应用快速增长的重要时期,将成为低空经济发展的重要推手。低空智联网是无人机产业发展的基石,是在低空空域实现“人—机—物”三元融合万物智能互联的重要基础设施。低空智联网体系架构就是依托天空地海网络基础设施,实现传统互联网络向万物智能互联网络演进,形成适合低空业务数字化、智能化运营的实体网络空间,可为无人机产业发展提供一个网络化、数字化、智能化的运营环境,对促进低空经济发展具有重要意义。  相似文献   
882.
The appropriate delivery of primary care services, an important policy imperative in many developed nations, is contingent on defining appropriate geographies to which these services are delivered. Primary Care Service Area (PCSA) geographies have been created in some countries to facilitate primary care policy making and have been utilized in a large body of research. In spite of their extensive use across rural and urban settings, the usefulness of PCSAs has not been evaluated. In this study, for the first time we put PCSAs to the test by comparing them to another small area geography - Postal Areas, and by exploring their usefulness in measuring relationships between Primary Care Practitioner supply and use. We find while PCSAs are better than Postal Areas in measuring relationships between General Practitioner supply and visits by patients, this relationship shows some heterogeneity across areas.  相似文献   
883.
随着近年的经济高速增长,中国已成为仅次于美国、日本的第三大韩国人移居地。在此背景下,运用实地调查和访谈方法,以北京望京为例,分析在华韩国人居住区及其族裔经济的形成与发展演变过程。北京望京是迄今为止在华韩国人聚集规模最大的社区,其以1998 年、2003 年为节点,经历了从花家地北移到望京西园,进而以望京西园为中心向外扩张的发展扩散过程。伴随着韩国人居住范围的扩大,面向韩国人的族裔经济也应运而生。当地的韩国人族裔经济多为韩国人和中国朝鲜族共同经营,以自我服务为主,已形成覆盖生产生活各方面的经济体系。相比中国国内的其他族裔聚居区,望京韩国人聚居区由于中国朝鲜族的参与,形成了主动融入、隐性隔离的特征,而这也为北京的移民管理和国际化城市建设带来了新挑战。  相似文献   
884.
江苏省人口—经济耦合与经济发展阶段关联分析   总被引:2,自引:0,他引:2  
运用灰色关联法建立耦合系统评价指标体系,构建人口与经济耦合关联模型,以江苏省县域为研究单元,基于第五次及第六次人口普查数据,定量评判人口与经济发展的耦合类型及特征,并将其与经济发展阶段相联系,研究耦合类型与不同经济发展阶段的变化规律。结果表明:2000年江苏省处于工业化初期,各县域大致划分为低水平(14个)、拮抗型(29个)、磨合型(20个)3种类型耦合区;2010年全省处于工业化中期向后期过渡阶段,各县域分为拮抗型(40个)、磨合型(11个)和协调型(12个)3种类型耦合区;耦合类型空间分布以长江为界,苏南与苏北两极分化明显,长江以北耦合类型水平较低,长江两岸耦合类型中等,长江以南耦合类型水平较高。从人口与经济发展耦合类型和经济发展阶段变化间的关联来看,在市场开放的条件下,区域的耦合类型随着经济发展阶段的升级而依次升级,经济发展阶段越高,人口与经济耦合程度越高,其耦合类型与经济发展水平在空间上则越趋向于协调一致。  相似文献   
885.
This paper attempts to overcome the dichotomy between the broadly different and largely separate fisheries science and management (FSM) and ecosystem science and management (ESM) knowledge systems that characterise the international literature and are found in fisheries management practice in different countries. The paper argues that the construction of a heuristic we term the fisheries problematic, around issues and contexts, reveals the breadth of international fisheries management concerns and the variety of contexts in which these concerns are being faced. Adopting a political economy informed nature-society approach the paper considers ecological and socio-economic processes in their institutional settings in an attempt to shift from the either/or arguments around fish or ecosystems found in the FSM or ESM literatures to investigation that is grounded in understandings of the historically and geographically specific trajectories of fisheries related interactions and understandings of how knowledge about the trajectories and their interactions is fashioned. Drawing on recent conceptual innovations in the field, the paper develops a matrix-centred approach to explore ecological, industry, community and policy domains in New Zealand’s Quota Management System (QMS) and Individual Transferable Quota (ITQ) fisheries management regime. The extended framework prioritises scrutiny of the interaction amongst the four domains, as a strategy to help develop institutional frameworks that facilitate behaviours that are societally inclusive. The paper offers three conclusions. First, the landscape of New Zealand fisheries issues is very much a product of the contingent interaction of the QMS, a management regime designed around the principles of a FSM approach and laid down in a neo-liberal political environment and Maori aspirations encompassing the fisheries sector. Second, the conceptual mapping of FSM and ESM perspectives over New Zealand’s fisheries management experience highlights that a number of management issues have been down played by the commitment to FSM, a situation that has led to on-going tensions between commercial, recreational and customary stakeholders regarding fisheries management. Put another way, there is more to running a sustainable fishery (as defined in the Fisheries Act 1996) than QMS and other tools and dialogue about the development of these should be a priority. Third and more generally, improved dialogue on fisheries questions is likely to be most expeditiously advanced by studies that explicitly conceptualise and contextualise ecological and socio-economic processes and their institutional arrangements.  相似文献   
886.
David Demeritt 《Geoforum》2008,(6):1811-1813
This essay contributes to the discussions initiated by Setten [Setten, 2008. Encyclopaedic vision: speculating on The Dictionary of Human Geography. Geoforum 39 (3), 1097–1104], about The Dictionary ofHuman Geography. Rather than focusing on the identity and relative exclusiveness of the contributors, I emphasize how successive editions of the Dictionary have helped reshape the discipline in two ways. First, the proliferation of texts, like the Dictionary, aimed squarely at a student market has gone hand in hand with a variety of changes to the political economy of publishing in geography. Second, human geography has increasingly come to be defined in terms of its concepts and theories. The paper ends by considering the implications of these changes for disciplinary unity and the future of geography given the increasing prominence of both of integrated environmental science and of GIS.  相似文献   
887.
随着我国枯竭矿山的不断增多,针对废弃矿山和中晚期矿山的生态环境恢复治理,提出建设国家级矿山公园。解决矿山废墟带来的环境恶化,体现了矿山公园的核心价值,是矿山复垦、复绿浩大工程的一部分。它具有循环经济模式的特点,即矿山生产的周期完结后,投入旅游产业经济循环中,为社会提供的新的旅游资源;矿山公园也为保护矿业遗迹和地质遗迹提供可能。  相似文献   
888.
The geographical detector model can be applied to either spatial or non-spatial data for discovering associations between a dependent variable and potential discrete controlling factors. It can also be applied to continuous factors after they are discretized. However, the power of determinant (PD), measuring data association based on the variance of the dependent variable within zones of a potential controlling factor, does not explicitly consider the spatial characteristics of the data and is also influenced by the number of levels into which each continuous factor is discretized. Here, we propose an improved spatial data association estimator (termed as SPatial Association DEtector, SPADE) to measure the spatial data association by the power of spatial and multilevel discretization determinant (PSMD), which explicitly considers the spatial variance by assigning the weight of the influence based on spatial distribution and also minimizes the influence of the number of levels on PD values by using the multilevel discretization and considering information loss due to discretization. We illustrate our new method by applying it to simulated data with known benchmark association and to dissection density data in the United States to assess its potential controlling factors. Our results show that PSMD is a better measure of association between spatially distributed data than the original PD.  相似文献   
889.
This article examines the role of so-called traditional stone waterspout technologies in struggles over urban modernization in Lalitpur, Nepal. In doing so, this article questions the status of tradition in urban theorizing and mobilizes the concept of sociotechnical imaginaries as a framework for understanding the contested spatial visions of urban development. In advancing this approach, this article analyses infrastructure as a visual discourse of materials, practices, and texts, including the label “tradition.” Findings indicate that stone spouts represent material and symbolic sites for residents to express discontent with hegemonic visions of modernization, legitimize certain cultural practices, and make claims on urban space. We argue that an alternate imaginary of urban development has emerged through the prism of traditional infrastructure. This article forwards sociotechnical imaginaries as a framework for situating the multiple and contested trajectories of urban modernization, particularly the ways in which past technologies come to shape desired urban futures.  相似文献   
890.
This contribution to a Debate on “The Nation-State and the city” foregrounds the recently adopted Urban Agenda for the European Union. It discusses the new role of cities in the European policy making process and its relevance for relations between State and City in the light of EU membership.  相似文献   
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