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11.
Arguments about the “positive” influence of growing transnational linkages have typically focused on their role in diffusing environmentally superior innovations which help to raise countries’ environment-efficiency. The present article empirically tests these claims by examining whether developing countries’ linkages with more CO2- and SO2-efficient economies contribute to domestic improvements in CO2- and SO2-efficiency. Our large-N, statistical findings caution against some of the efficiency-oriented optimism voiced by supporters of globalization. Although imports ties with more pollution-efficient countries are found to spillover into improved domestic CO2- and SO2-efficiency, neither transnational linkages via exports, inward foreign direct investment (FDI) nor telephone calls appear to have any influence on domestic pollution-efficiency.  相似文献   
12.
吕海萍  池仁勇  化祥雨 《地理科学》2017,37(11):1649-1658
以中国31个省域为空间样本,运用趋势面、引力模型和探索性空间数据分析法研究中国创新资源协同空间联系的动态变化特征,通过构建创新资源协同势能与区域经济增长空间面板计量模型,实证探讨创新资源协同空间联系与区域经济增长关系。研究结果表明:2003~2014年中国各省域创新资源协同状况整体呈现“东南高,西北低”的空间分布特征;创新资源协同空间联系呈现显著的区域不平衡性,空间网络结构分布格局变化显著:从简单雏形逐渐发育为“鸡爪型”、多核心复杂化的“网络型”空间结构;创新资源协同势能呈现显著的空间正相关,主要向东部沿海地区集聚;实证结果显示中国区域经济增长存在显著的空间溢出效应,创新资源协同空间联系对区域经济增长表现出显著的促进效应,可以通过直接效应、间接效应和总效应空间溢出促进区域经济增长。  相似文献   
13.
粤港澳区域联动发展的关键科学问题与重点议题   总被引:2,自引:1,他引:1  
在新时期新背景下,实现粤港澳区域联动发展具有紧迫性、必要性和重大现实意义。本文认为研究粤港澳区域联动发展需要以区域一体化理论体系、“全球—地方”尺度理论、区域空间相互作用理论体系为主要的理论基础。其关键科学问题是研究“一国两制”下粤港澳尺度的区域联动理论,探索粤港澳区域联动的机制、关键因素、模式与路径;提出了粤港澳区域联动发展关注的4个重点议题:①粤港澳区域一体化/协同理论的研究与探索;②粤港澳地位与作用研究;③粤港澳联动的多尺度、多主体影响机制与模式研究;④粤港澳联动发展的实施路径研究。  相似文献   
14.
Financial services are undergoing a major period of internationalization. National markets are interlinked by telecommunications, a process induced through deregulation and new communications technologies. This paper reviews the recent, intertwined trends in the finance and telecommunications industries in light of urban and regional restructuring theory, cites several company-specific examples, explores the impacts on the international urban hierarchy and the labor process (e.g., back offices), and assesses the role of teleports. Finally, it offers an agenda for further research.  相似文献   
15.
冯亿年  李亚刚 《探矿工程》2012,39(5):22-24,27
在河南周口市淮阳县地热井施工中,发生了粘性土粘附卡钻、砂桥卡钻等事故,首先采用提拔、碱泡、爆破等措施进行处理,仍有较长钻具遗留在孔内,然后采用套铣方法进行处理,成功将遗留钻具从孔内提出,完成了孔内事故的处理。总结了该孔处理经验,可供类似工程参考借鉴。  相似文献   
16.
罗晓斌  罗凯 《探矿工程》2012,39(10):23-25,31
偏心楔是定向钻进技术的一种方法和手段,偏心楔钻进技术的关键工序是孔底架桥和在硬岩地层过楔面钻进技术。通过生产、科研相结合,对液压金属孔底塞和金刚石钻头进行了改进研究,经过几年的生产应用和3个钻孔应用效果对比,取得了较好的效果。  相似文献   
17.
跨国公司对区域经济发展影响的理论研究   总被引:9,自引:0,他引:9  
李小建 《地理研究》1997,16(3):101-111
(1)根据相邻学科的理论并基于前人研究成果,提出跨国公司对区域经济影响、跨国公司与区域关系以及两者关系的决定因素三层次研究思路;(2)以生产链、组织链和所有权关系三个关联系统和区域等级关系作为跨国投资的理论背景,导出跨国公司──区域综合分析方法;(3)跨国投资对区域发展影响具广泛性、层次性、区域性、多面性、差异性和时间性特点,跨国公司与投资地关系具互补性、竞争性和变化性特点,影响两者关系的主要因素为社会政治背景、结构状况和相对地位。  相似文献   
18.
An 8 m core from the central plain of the Petit Lac d'Annecy, France, two floodplain cores, river bedload sediments and several hundred soil samples from the catchment have been studied using magnetic techniques. The soils, mainly developed on limestones and local glacial tills, show widespread magnetic enhancement with higher ferrimagnetic concentrations and contents of SP grains than found in the lake sediments. Some soils show significant concentrations of canted antiferromagnetic minerals (mainly haematite). Using magnetic quotient parameters the surface soils are classified into four mineralogical types. The lake and floodplain sediment properties over the past 6000 yrs can largely be explained by the erosion and deposition of these sources, with a smaller superimposed biogenic (magnetosomes) signal. Derived sediment-source linkages allow the construction of several hypotheses about geomorphological changes in the catchment system: (i) the long-term erosion of high altitude unweathered substrates has gradually increased towards the present day; (ii) the erosion of high altitude soils has increased within the last 1000 yrs, possibly during the period of the 'Little Ice Age'; (iii) shifts towards an increased erosion of surface lowland soil occurred ~2000 and 1000 yrs ago and may be linked to an accelerated accretion of floodplain overbank deposits; (iv) there has been a significant storage of surface soil within floodplains, which leads to an underestimation of the importance of soil erosion in the lake sediment records; (v) the sediment transported by high magnitude, low frequency flood events has shifted in source from high altitude soils before ~1000 cal. yr BP to lowland and mid-altitude free draining soils after ~1000 cal. yr BP.  相似文献   
19.
The Bohai Strait Cross-Sea Channel (BSCC) is a mega-strategic project that connects the Shandong Peninsula and northeastern China. After half a century of research, this project has entered its preliminary planning phase. Based on the Chinese modern transportation system database, this paper applies Dijkstra's algorithm to study the impacts of the BSCC on the structure of Chinese transportation accessibility and discusses the spatial and temporal changes and the strength of economic linkages among the eight affected coastal urban agglomerations before and after the construction of the BSCC. This study concludes that: (1) the BSCC will open up a northeast–southwest traffic artery in coastal areas of China that will significantly improve the transportation accessibility of both these coastal areas and northeastern China as a whole, which cover an area of 2.18 million km2, and on average will reduce the travel time of nationwide prefecture-level cities by 16 min; (2) the BSCC will significantly improve the total economic linkages (TELs) of urban agglomerations of the Central South Liaoning, the Shandong Peninsula and the Harbin–Changchun transport link and will decrease the spatial differences in the strength of cities' economic linkages, which will benefit the integration of the Bohai Economic Circle; (3) the BSCC will eliminate the segregation between the two coastal economic groups brought about by the Bohai Strait. This will promote the revitalization of the old industrial base in northeastern China by expanding the radiation scope of the Yangtze River Delta and the Shandong Peninsula across the Bohai Strait into northeastern China. Additionally, the BSCC will enhance the economic linkages between urban agglomerations in northeastern China and the western shore of the southeastern coast, Pearl River Delta, and North Gulf of Guangxi on the southeastern coast. Finally, it will create northeast–southwest economic integration in these coastal areas. This research will assist decision-making for the BSCC project and other cross-sea tunnels in China.  相似文献   
20.
In 1983, Ghana embarked on a program of structural adjustment under the auspices of the World Bank and the International Monetary Fund, to resuscitate the economy and to foster development. This paper utilizes the Lagos Plan of Action, a comprehensive, continent‐wide effort and African‐led policy strategy for the economic development of the African continent, to examine the contribution of adjustment to the development of an integrated economy in Ghana. Adjustment is examined as a form of structural transformation, as evidenced by the emergent intranational (intra‐ and inter‐sectoral) and international linkages in the formal wood processing industry, a key sector with tremendous potential for such linkages. Intranationally, this study shows that, as in the pre‐adjustment years, inter‐sectoral linkages, although important, were not dynamic enough to play a significantly galvanizing role in the nation's economic development. However, intra‐sectorally, a dramatic expansion in lumber exports led to an unprecedented constriction in the traditional forward linkage between sawmills and downstream processors. This forced the latter to depend on the informal sector for inputs. Internationally, Ghanaian firms operated as subcontractors of convenience for firms overseas (particularly in Europe) via an expanded forward linkage, reflecting a new “colonial relationship” under the program.  相似文献   
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