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151.
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   
152.
Central Asian countries are located in the heartland of the Eurasian Continent. Their geographic location puts their energy flows under tremendous geopolitical pressure from the countries along their limited number of pipelines. With energy trade data from the United Nations Comtrade Statistics Database in the period from 2005 to 2016, this paper evaluates energy security of Kazakhstan and Turkmenistan (exporter) and Kyrgyzstan (importer) using three standards: correlativeness, diversity, and the impact of international relations. It concludes that Kazakhstan and Turkmenistan’s oil markets are balanced in terms of correlation and diversification, and thus less subject to geopolitical pressure. Turkmenistan’s gas markets, on the other hand, still have tremendous exposure to geopolitical risks for lack of diversification. Kyrgyzstan, as an energy importer, could rely on a few neighboring countries for energy supply. We found out that the three Central Asian countries’ energy security is largely determined by four political factors: the relationship with Russia, the new “great game” in Eurasia, the rise of China, and Central Asian regional geopolitical configuration.  相似文献   
153.
利用2003—2013年中国典型资源型城市的面板数据,在考虑潜在内生性的条件下,使用动态面板系统广义矩估计方法,开展"资源诅咒"假说的再检验,进一步讨论资源型城市的人力资本能否有效缓解"资源诅咒"。结果表明:中国资源型城市普遍存在"资源诅咒"现象;人力资本对经济增长的正向作用虽在一定程度上可以弥补资源产业依赖对增长的负向作用,但却不能明显抑制"资源诅咒";资源型城市普遍存在资源产业依赖对人力资本投资的"挤出"。  相似文献   
154.
在旅游场景中,旅游交往与凝视无处不在。国际游客来华旅行,接触普通的中国游客、百姓,在最生活化的凝视中强化对中国社会、生活、文明各个方面的认知。本研究以中国最知名的山水实景演出——"印象·刘三姐",为研究场景,以国际游客的自由评论为数据来源,利用Leximancer分析国际游客的"印象·刘三姐"观看体验。研究表明,东道主与在场观众的互动是国际游客体验的重要部分。进一步分析发现,国际游客对演出感到满意,对东道主(当地农民、渔民)的表演大加赞赏。可是,不少国际游客对在场的部分中国游客行为,特别是观演礼仪,感到不满。本研究对旅游资源开发、游客教育、塑造公民文明旅游行为起一定的借鉴意义。  相似文献   
155.
In recent years urban geographers have devoted considerable attention to the dynamics of policy mobility. After reviewing the progress achieved in this literature, in this article I offer two distinctive contributions. First, I draw on the “argumentative turn” in policy studies and related fields in order to develop an alternative conceptualization of urban policy mobility that pays greater attention to its discursive and argumentative aspects. I thus reassert the significance of democratic processes in the negotiation of urban policy. Second, I outline an alternative methodology for the study of urban policy mobility, focusing on the analysis of argumentation. I apply this methodology to historical instances of urban policy mobilities arising from a recent research project that aimed to historicize the phenomenon of the “model city,” defined as the local deployment of another city’s experience as an argumentative resource supporting particular policy claims.  相似文献   
156.
The association between spatial patterns of retail activity and the spatial configuration of street networks was examined by means of the space syntax methodology in eight Israeli cities that represent two city types, characterized by different planning approaches and urban growth: (i) new towns, which were established according to a comprehensive city plan and modern planning concepts of “tree-like” hierarchical street networks and “neighborhood units”; (ii) older cities, where street networks and the spatial patterns of retail activity were formed incrementally during their growth. Unlike in older cities, retail activity in new towns concentrates in relatively less-accessible and intermediate locations. This is indicated by a weak correlation between retail activity and the street network’s Integration and Choice centrality measures. The comparison between Israeli cities illustrates the influence of urban growth and planning approaches on the formation of retail activity and its interaction with the structure of the street network.  相似文献   
157.
The smart city encompasses a broad range of technological innovations which might be applied to any city for a wide variety of reasons. In this article, I make a distinction between local efforts to reshape the urban landscape, and a global smart city imaginary which those efforts draw upon and help sustain. While attention has been given to the malleability of the smart city concept at this global scale, there remains little effort to interrogate the way that the future is used to sanction specific solutions. Through a critical engagement with smart city marketing materials, industry documents, and consultancy reports, I explore how the future is recruited, rearranged, and represented as a rationalization for technological intervention in the present. This is performed amidst three recurring crises: massive demographic shifts and subsequent resource pressures, global climate change, and the conflicting demands of fiscal austerity that motivate the desire of so many cities to attract foreign direct investment and highly skilled workers. In revealing how crises are pre-empted, precautioned, and prepared for, I argue that the smart city imaginary normalizes a style and scale of response deemed appropriate under liberal capitalism.  相似文献   
158.
基于制造业企业网络视角的城市网络核心—边缘结构的研究将加深对城市网络演化规律的理解。利用2020年中国制造业500强企业网络数据和隶属联系模型构建城市网络,研究了中国城市网络核心—边缘结构的演化特征,定量测度了核心—边缘结构的影响因素,并根据国际生产折衷理论解析了城市网络地位分异的动力机制。研究发现: 2005—2020年,核心区块的城市数量逐渐增加,主要由直辖市、经济特区以及东、中部地区的省会城市组成,这些城市通过互惠性的链接关系形成了凝聚子群,网络权力较为集中;边缘区块的城市则主要位于中、西部地区,城市间经济联系相对稀疏,整体网络结构并不稳定,城市的发展受到了网络资本的约束。关键资源、基础设施和区位优势是影响中国城市网络地位的决定性因素,择优选择、网络邻近和路径依赖构成了中国城市网络核心—边缘结构演化的动力机制,这将进一步增强核心城市的网络地位。在网络环境下,城市间的差距趋于扩大,城市网络地位的提升取决于城市在网络中的影响力,中国城市化政策需要做出相应调整。  相似文献   
159.
南极海豹类生态学   总被引:1,自引:0,他引:1       下载免费PDF全文
描述了南极海豹的种类组成、资源量和种类状况等一般性生态学问题,着重讲述了这些海豹在研究全球变化中所起的作用等科学前沿问题;同时,就海豹研究在各国际组织中的地位阐述了意见。  相似文献   
160.
The developing countries at present have a high urban growth rate that is likely to continue for at least another quarter-century. In addition, many of these urban centres are located in the Neogene plate boundary zones and are subject to multiple earthquake and volcanic hazards. Slope failures and accelerated surface and channel erosion are particularly severe in cities near active plate margins, and in areas affected also by tropical cyclones. We discuss two extreme cases: Singapore and Kingston (Jamaica). Singapore is located in a stable environment and the urbanization related problems of flood and slope instability have been reduced by proper building and drainage practices at a considerable cost. In Kingston, the external disturbances are repetitive, large-scale, and very difficult to control. The fast-growing cities in the tropics need to be carefully monitored, especially when located in an unstable physical environment. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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