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On March 11, 1989, twenty-four governments called for the development, within the framework of the United Nations, of
new institutional authority, either by strengthening existing institutions or by creating a new institution which, in the context of the preservation of the earth's atmosphere, shall be responsible for combating any further global warming of the atmosphere. (Declaration of The Hague, 1989. p. 1308)  相似文献   
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In this paper, we first develop a measure of total factor productivity (TFP) growth and summarize a source-of-growth analysis for the manufacturing sector of 48 states. As have others, we find little association between TFP growth differentials and output growth differentials for census regions. At the staterather than the regional level, however, we find a positive association between TFP growth and output growth. We use cross-sectional data to estimate the determinants of the variation in TFP growth. Two results emerge that are important for regional policy and for understanding national productivity trends. First, state investments in education and in transportation infrastructure may affect TFP growth. Second, energy price increases in the early 1970s had no differential effects on productivity growth across states. We also explore the determinants of manufacturing output growth and find that TFP growth, demand growth, wage growth, wage levels, and state corporate income tax rates are significant.  相似文献   
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Compared to the geographic wasteland south of your border, geography appears to have fared well in Canada, both as a formal discipline extending our understanding by illuminating the human and physical worlds, and as a subject taught at all levels to create informed and aware citizens. I known you think much remains to be done, and perhaps things always look a bit greener on the other side of the hill, but I hope you will not mind my somewhat envious gaze. In fact, when I received the five volumes of the 'curriculum guideline' for geography, issued by the Ontario Ministry of Education for the intermediate and senior divisions of your high schools (ome 1988), my feelings were not so much envy as panic, a panic that rapidly induced something close to intellectual paralysis. Because in a moment I can only describe now as utterly weak and foolish, I started to read them, only to learn that your senior students 'analyze, interpret … explain … design and develop networks, systems and simulations that involve six or more variables' (ome 1988, A12).
In retrospect, I still think my panic was justified. After 30 years of hard post-doctoral work I have reached the point where I can think about the interactions of maybe three variables, but hardly the combinatorial possibilities of six. Such ineptness would mean that I might just squeeze into your tenth grade and from there slowly work my way over the next two years towards those Olympian heights of analytical thought where dwell Ontario's high school graduates.  相似文献   
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地理学家的演讲与他们运用文字、图象所作的交流同样值得重视.美国的地理学可以通过下述途径得到加强,即围绕地点、地区和全球联系发展实质性演讲,促进自然地理的发展,恢复地理生态的传统.地理信息系统(geographic information systems)对于完成上述任务,对于改进地理学科以满足不断出现的需要,将是一个非常有用的工具.如果我们能够避免自己拆自己的台,避免不现实的空想,避免玩弄语言技巧,而是坚持在大学里进行高质量的教学,并在教师和从事地理实践工作的人员之间开展学术交流,那么地理学将会变得更加有效.我们有一个前所未有的机会来帮助改进美国的中小学地理教育.  相似文献   
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This article explores the articulation—in different forms, at different periods, and by different actors—of ‘national self‐determination’ in Somalia and across the Somali‐speaking regions of the Horn of Africa. It explores how this concept can be understood in the context of protracted political fragmentation in Somalia—considering unresolved debates over the ideological foundations of state reconstruction, disagreements about the suitability of federalism, aspirations for the recognition of an independent Republic of Somaliland, and the distinctive trajectory of the Somali Regional State in Ethiopia. Taking a comparative, cross‐border and wide‐angled historical approach, the article argues that ideas of an ethno‐linguistically, culturally and religiously defined Somali ‘nation’ continue to coexist (and be reproduced, updated and used) within an environment of extreme political fragmentation and across multiple ‘state’ boundaries. This argument is made through comparative analysis of contemporary examples of the performance of Somali state and nationalist identities within and beyond the region and the distinctive transnational Somali‐language media environment within which these ideas circulate and compete.  相似文献   
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Recent research in central Europe is changing our understanding of the role of centers in economic and social systems of late prehistoric times. Increased attention to smaller, more typical settlements shows that they engaged in economic activities similar to those at the large, fortified complexes. Abundant new evidence pertaining to ritual activity indicates that ritual was often integrated into daily life at settlements. The evidence from the exceptionally rich data on late prehistoric central Europe can be of substantial value for developing models applicable to contexts in other parts of the world.  相似文献   
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