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121.
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123.
The lognormal approach to predicting local distributions of selective mining unit grades 总被引:1,自引:0,他引:1
A. G. Journel 《Mathematical Geology》1980,12(4):285-303
124.
新型城镇化的人地耦合异速增长分析方法 总被引:1,自引:0,他引:1
在新型城镇化背景下的城市人口规模与用地面积变化具有复杂性,研究两种要素城镇化水平的相对增长关系,有助于探索人地耦合发展的协同态势及变化动因。本文选取广州市2000—2015年的Landsat时序影像与2000、2010和2015年的人口普查与年鉴数据,在街道(乡镇)尺度上计算人口土地城镇化耦合指数识别4种耦合类型,并在此基础上提出年均增长率异速关系拟合方法。研究结果表明:① 2000—2015年广州市街道(乡镇)人口和土地城镇化呈现明显的圈层结构(核心、内、外圈层)特征,4种人地耦合类型的异速增长分别呈现正异速、负异速、负幂律3种形式,证明人地耦合分类的异速增长建模方法有助于分析人地城镇化的动态演化过程;② 基于人地耦合指数的异速标度分析表明,核心圈层—内圈层—外圈层结构上分别形成了高度集约—集约—相对粗放式扩张的发展格局,结合城市更新改造的空间分析,说明这一特色新型城镇化模式在广州具有一定成效,已初步形成了核心圈层与内圈层协同发展的态势,但需要注意防控外圈层的粗放型增长。研究结果可为新型城镇化理论内涵的认知探索和广州市案例的实证研究提供支持。 相似文献
125.
免疫进化算法是在现有进化算法的基础上发展起来的一种新的优化算法,其具有许多独特的性能.把该算法应用于排放口最优规划,结果表明:免疫进化算法不仅取得了良好的应用效果,而且成功地解决了此类问题中存在的非线性目标函数、约束条件过于复杂、"维数灾"等问题. 相似文献
126.
中国城市地理学近期进展 总被引:11,自引:0,他引:11
中国城市地理学的兴盛时期始于70年代中期,至80年代进入历史以来最旺盛的发展时期。城市地理学主要研究城市体系、城市化、城市地域结构与具体的大小城镇。其重要的实践领域则主要通过城市规划和区域规划、国土规划。特别是70年代中期借助于我国城市规划工作的复兴,为城市地理学的发展提供了广阔的实践基础。 相似文献
127.
《Marine Policy》2015
Transboundary cooperation is viewed as an essential element of Marine Spatial Planning (MSP). While much of the MSP literature focuses on the need for, and benefits of, transboundary MSP, this paper explores the political and institutional factors that may facilitate the effective transition to such an approach. Drawing on transboundary planning theory and practice, key contextual factors that are likely to expedite the transition to transboundary MSP are reviewed. These include: policy convergence in neighbouring jurisdictions; prior experience of transboundary planning; and good working relations amongst key actors. Based on this review, an assessment of the conditions for transboundary MSP in the adjoining waters of Northern Ireland and the Republic of Ireland is undertaken. A number of recommendations are then advanced for transboundary MSP on the island of Ireland, including, the need to address the role of formal transboundary institutions and the lack of an agreed legal maritime boundary. The paper concludes with some commentary on the political realities of implementing transboundary MSP. 相似文献
128.
《Marine Policy》2015
The adoption of UN Convention of the Law of the Sea in 1982 created optimism for indigenous peoples and marginalised coastal communities that they may (re)gain control of, or improve access to, marine resources. However concerns were also raised that opening the seas to industrial development might create threats for traditional users of the sea. Twenty-five years later the potential enclosure of large areas of coastal seas to marine renewable energy development is reigniting debates about marine governance, access and control over marine resources. Case studies in Scotland, Canada, New Zealand and Australia reveal a dynamic tension between: an economic development ‘blue growth’ agenda requiring the creation of private rights in the sea; and socio-political drivers which seek to address historic injustices and increase access to natural resources by indigenous and marginalised coastal communities. As yet there is little evidence of this tension being adequately addressed by emerging institutional frameworks for managing marine resources. 相似文献
129.
《Marine Policy》2015
This paper presents the Biogeographic Assessment Framework (BAF), a decision support process for marine spatial planning (MSP), developed through two decades of close collaborations between scientists and marine managers. Spatial planning is a considerable challenge for marine stewardship agencies because of the need to synthesize information on complex socio-ecological patterns across geographically broad spatial scales. This challenge is compounded by relatively short time-frames for implementation and limited financial and technological resources. To address this pragmatically, BAF provides a rapid, flexible and multi-disciplinary approach to integrate geospatial information into formats and visualization tools readily useable for spatial planning. Central to BAF is four sequential components: (1) Planning; (2) Data Evaluation; (3) Ecosystem Characterization; and (4) Management Applications. The framework has been applied to support the development of several marine spatial plans in the United States and Territories. This paper describes the structure of the BAF framework and the associated analytical techniques. Two management applications are provided to demonstrate the utility of BAF in supporting decision making in MSP. 相似文献
130.
《Marine Policy》2015
An important task of natural resource management is deciding amongst alternative policy options, including how interventions will affect the dynamics of resource exploitation. Yet predicting the behaviour of natural resource users in complex, changeable systems presents a significant challenge for managers. Scenario planning, which involves thinking creatively about how a socio-ecological system might develop under a set of possible futures, was used to explore uncertainties in the future of the Indian Ocean tuna purse seine fishery. This exercise stimulated thinking on how key social, economic and environmental conditions that influence fleet behaviour may change in the future, and how these changes might affect the dynamics of fishing effort. Three storylines were explored: an increase in marine protection, growing consumer preference for sustainable seafood, and depletion of tuna stocks. Comparing across several possible future scenarios, a number of critical aspects of fleet behaviour were identified that should be important considerations for fishery managers, but which are currently poorly understood. These included a switch in fishing practices, reallocation of effort in space, investment in new vessels and exit from the fishery. Recommendations for future management interventions in the Indian Ocean were offered, along with suggestions for research needed to reduce management uncertainty. 相似文献