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981.
战略耦合的研究脉络与问题   总被引:14,自引:9,他引:5  
刘逸 《地理研究》2018,37(7):1421-1434
在回顾经济地理学中较为前沿的战略耦合概念的起源、发展与研究现状的基础上,对战略耦合研究的优点与问题展开评述,认为当前研究在战略耦合模式的探讨中,主要基于经验总结而缺乏对影响变量,特别是空间变量的阐述,存在一定的模糊性。为理解该问题的根源,追溯了全球生产网络和全球价值链两个学派的争论和最新进展。在认可全球价值链理论解释力的同时,认为当前全球生产网络2.0版本的研究框架仍然没有解决模糊性的问题,而且全球生产网络的分析框架主要侧重于主导企业视角来构建战略耦合的发生机制,忽略了后发地区和企业的主动性。因此,借鉴传统经济地理学研究,充分考虑主导企业和后发地区的行为逻辑,提出经济活动的空间粘性和区域的区位优势这两个变量,重构了战略耦合的分析框架,并进行理论阐述。该项理论构建有助于更好地厘清战略耦合的发生机制,帮助发展中国家和地区判读发展机遇,确立产业发展与升级战略。  相似文献   
982.
梁育填  周政可  刘逸 《地理学报》2018,73(8):1449-1461
随着“走出去”战略的实施和“一带一路”倡议的提出,中国在全球化经济中逐渐成为国际投资的主要力量之一。海外华人华侨网络曾经积极促进外商对华的直接投资,是否在这个过程中再次扮演积极的作用,是当前经济地理领域尚未充分探究的问题。因此,本文从经典的区位选择问题切入,探究海外华人华侨网络与中国企业海外投资的区位选择的关系,利用2001-2016年中国企业投资东南亚国家的数据,通过混合逻辑模型回归分析海外华人华侨对中国企业投资区位的影响。结果表明:① 从整体上看,东南亚各国的华人华侨规模和中国企业对外直接投资的区位选择之间存在显著的正相关关系;② 从投资时间上看,海外华人华侨规模与中国企业对外直接投资区位选择之间的关系显著性呈现扩大趋势,说明华人华侨在促进中国企业对外投资方面存在较大潜力;③ 从投资的行业和环节上看,不同行业和不同职能部门的企业在东南亚投资中海外华人华侨在其投资区位选择中所起的作用不同。  相似文献   
983.
Bridging organizations facilitate a range of governance processes, including cooperation and social learning, and are theorized to be a key component of robust governance systems. In this article, we use node removal simulations to test structural hypotheses of robustness in a regional water governance network in Central America. We investigate the response of network measures supporting core governance processes to the targeted removal of bridging organizations and other actors, which we compare to random and centrality-based simulations. The results indicate removing bridging organizations has a greater impact on the network than any other type of actor, suggesting bridging organizations are critical to the robustness of the governance system. Furthermore, network structures supporting cooperation may be less robust than structures facilitating social learning. We conclude with policy implications of the research findings as they relate to the exit problem in governance systems with a large presence of international development actors.  相似文献   
984.
Participatory scenario planning (PSP) processes rely on accurate stakeholder identification to develop a key set of critical uncertainties. While many stakeholder analysis methods are able to identify stakeholders and describe their relationships, we found these efforts to have limited use in the fast-moving and in-depth approach of PSP research. We find that social network analysis (SNA) is an efficient, objective, and transparent approach to stakeholder identification in highly contested natural resource management issues. We present a case study of our research on Alaska’s Kenai Peninsula to describe how SNA’s ability to contextualize the relations between actors can benefit participatory research.  相似文献   
985.
粤港澳大湾区发展的理论框架与发展战略探究   总被引:5,自引:3,他引:2  
赵晓斌  强卫  黄伟豪  线实 《地理科学进展》2018,37(12):1597-1608
粤港澳大湾区是在“一带一路”倡议下,由珠三角经济圈的强化合作而产生的新地理概念。作为新兴的全球化港湾,粤港澳大湾区如何突破新自由主义框架理论,探索出符合社会主义市场经济体制的发展路径,是当前决策者和规划者需要思考的重要问题。本文简要梳理了现有的城市群、区域增长极理论,新经济地理集群理论,全球产业链网络理论并结合大湾区现状优势,对湾区发展战略定位与发展路径进行探究,认为可通过粤港澳三方通力合作,创造一个内生型的经济与产业本土增长模式为主要方向。具体表现为:首先,要以先进制造业为立足点、实现自我创新的产业升级,形成完善的制造业产业链,并成为全球生产网络的重要节点与区域性枢纽;其次,大湾区还应利用自身的科研与教育、金融与创新资源优势,推进“一国两制三关税区”、尤其是与香港在大湾区建设中的全方位参与联动,完善产权制度,加强合规和规则经济的市场经济体系建设,将大湾区打造为中国的科创中心及全球性金融中心。  相似文献   
986.
王菲  杨秋菊 《极地研究》2018,30(2):123-131
极光是由带电粒子经磁层—电离层碰撞大气而产生的。面对形态各异、演变过程复杂的极光图像,对其合理分类为进一步探究日地电磁活动和能量耦合等空间物理问题奠定了基础。针对该问题,引入深度学习的方法,通过卷积神经网络模型自主表征极光特征并实现极光图像分类。该方法对2003年北极黄河站越冬观测的38 044幅和8 001幅典型极光图像分类正确率达93.17%和91.5%;自动识别2004—2009年观测数据的极光形态,4类极光时间分布规律与三波段激发谱能量分布基本一致。实验结果表明,基于卷积神经网络的极光表征方法,能有效实现极光图像的自动分类。  相似文献   
987.
Unimpeded trade is one of the cooperation priorities in the Belt and Road Initiative proposed by China. On 15 May 2017, the Joint Communique of the Leaders Roundtable of the Belt and Road Forum for International Cooperation reaffirmed the participants’ shared commitment to build an open economy and ensure free and inclusive trade. The Belt and Road Initiative (BRI) is not only China's new action to drive its open and global development, but also a platform for an increasing number of countries to explore free and inclusive trade and promote a universal, rule-based, open, non-discriminatory, and equitable multilateral trade system. It is therefore important to examine the topological relationship between the BRI and global trade networks. More specifically, this article first analyzes the community structure of trade networks using a community detection algorithm, and then estimates the topological relationship between different trade communities. The findings of this article are as follows. First, this research identified three trade communities and two sub-communities in the BRI trade network, in which China is the core, Russia is the sub-core of the biggest trade community, and India, United Arab Emirates, and Saudi Arabia are cores of the second trade community (South Asia-West Asia). Second, it identified five trade communities in the global trade network, centred on China, USA, Russia, India-United Arab Emirates, and Germany- Netherlands-France-Britain and other European developed countries. Third, the topological analysis indicated that in the global trade network, most BRI countries are attracted by the core nodes of the BRI regions, such as the China, Russia and India-United Arab Emirates core nodes, and have strong trade contacts with BRI countries. Most Central-East European countries are mainly attracted by Germany-Netherlands-France-Britain and other developed European countries with a low penetration of BRI trade. Although some Southeast Asian countries are incorporated into the Asia-Australia-South Africa community with China as the core, they still need to strengthen trade linkages with BRI countries.  相似文献   
988.
Maritime network dynamics before and after international events   总被引:1,自引:0,他引:1  
Investigating the influence of international events on global maritime networks is a challenging task that must comprehensively incorporate geographical, political, and maritime sciences. Understanding global maritime network dynamics is an initial and critical step in this investigation. This study proposes an automatic identification system (AIS)-based approach to understanding maritime network dynamics before and after international events. In this approach, a spatiotemporal modeling method is introduced to measure the similarity in shipping trends before and after international events. Then, a spatiotemporal analytic framework is proposed to understand the maritime network dynamics by grouping similar situation, and assessing possible indirect effects within a network. Finally, three case studies of international events, military conflict, lifted economic sanctions, and government elections, were used to investigate the observed network dynamics possibly affected by international events. The results indicate that container, tanker, and bulk shipping between India and its connected countries all declined more than 69% after military conflicts between India and Pakistan in August 2015. Tanker shipping between Iran and the United Arab Emirates increased 51% after economic sanctions on Iran were lifted. Container shipping between Sri Lanka and Singapore, Malaysia, and India increased more than 74% after the general election in Sri Lanka. These investigations demonstrate the feasibility of the proposed approach in assessing the possible effects of international events on maritime network dynamics.  相似文献   
989.
From the development of modern transportation to the current era of high-speed transportation networks, the Beijing-Tianjin-Hebei (BTH) region has always played a national leading role in land transportation development of China. In order to explore the long-term evolutionary characteristics of land transportation in the BTH region, this paper utilized a temporal scale of 100 years to systematically interpret the development process of the land transportation network. Taking 13 cities within the BTH region as research anchor cities, we took into account “leaping” mode of transportation in order to investigate the evolution of accessibility. Our research shows the following results: (1) The land transportation network in the BTH region has undergone five stages of development: the initial period of modernization (1881–1937); the period of stagnation of transportation development (1937–1949); the network expansion period (1949–1980); the period of trunk construction (1980–1995), and the period of high-speed transportation network development (1995–present). The network structure centered around Beijing has existed from the outset of modern transportation development. (2) The accessibility spatial pattern of land transportation in BTH region has evolved from expansion along traffic corridors to the formation of concentric circles. The stratified circular structure of transportation in anchor cities has gradually developed into a contiguous development pattern. (3) There are clear hierarchical differences in the transportation structures of anchor cities. Beijing has always been at the top of this hierarchy, while the hierarchical position of Zhangjiakou has fallen noticeably since 1949. The Beijing-Tianjin region was the first region to form a short-duration transportation circle structure, while the transportation advantages of the central part of Hebei Province, which is located in the center of the BTH transportation region, have yet to be realized.  相似文献   
990.
云雷达和微波辐射计联合反演大气湿度廓线的初步研究   总被引:1,自引:0,他引:1  
丁虹鑫  马舒庆  杨玲  车云飞 《气象》2018,44(12):1604-1611
利用中国气象局大气探测试验基地的微波辐射计亮温值、对应的云雷达测得的反射率因子和L波段探空数据,采用BP(back propagation)神经网络作为反演工具,反演得到大气垂直湿度廓线。将天气情况分为晴天、低云、中云和高云四种情况,对比不加入反射率因子的反演湿度廓线,分析两种反演方法在各高度层的均方根误差。对比结果表明,加入反射率因子的反演湿度廓线与探空廓线的相关系数平均值为0.862,均方根误差为14. 9%,而不添加反射率因子的相关系数平均值为0.763,均方根误差为19.2%。  相似文献   
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