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31.
This article describes the conditions for the development of four industrial clusters and the mechanisms of their integration in the regional economy. The case studies are the aerospace and apparel clusters in Montreal, and the agri‐food and marine science and technology clusters in the Lower St. Lawrence region. Clusters are defined as arrangements of businesses, government actors, public authorities, and local intermediary organizations in a local area. However, the study shows that clusters are based on actors and processes operating at different scales, from the local to the global. It also shows the importance of the sectoral leadership acknowledged by the different stakeholders.  相似文献   
32.
Concurrent to the surge of U.S. forces in Iraq between 2006 and 2008, Sunni tribesmen in the U.S. Marine‐controlled western Anbar province of Iraq experienced an “awakening” movement, which led them to side with U.S. and coalition forces. The Sunni Awakening demonstrates that individuals will often realign because of betrayal and opportunities for advancement. It also demonstrates that individual motives can have macrolevel social consequences. Complexity theory suggests that political factions will realign based on individual considerations that then develop into macrolevel movements. Complexity theory also combines both agency (in terms of microbehaviors) and structure (in terms of initial conditions). An important concept within the complexity literature is the idea of “critical mass.” Theories of self‐organization suggest that individual considerations aggregate to a point of critical mass to become macrolevel movements. In the case of Iraq, you had individuals who decided as individuals to align with the Americans, but the macrolevel Awakening movement did not gain momentum until enough individuals had joined the movement. This pattern suggests that complexity theory can be used as a framework for understanding how critical mass is achieved in realignment.  相似文献   
33.
Handwerker, W. Penn, ed. Births and Power: Social Change and the Politics of Reproduction. Boulder: Westview Press, 1990. 227 pp. including chapter references. $27.50 paper.

Landers, John, and Vernon Reynolds, ed. Fertility and Resources. Cambridge: Cambridge University Press, 1990. vii + 199 pp. including chapter references and index. $59.50 cloth.  相似文献   
34.
Genetics and African Cattle Domestication   总被引:1,自引:0,他引:1  
Whether cattle domestication occurred independently on the African continent is among the most controversial questions in the Holocene archaeology of northern Africa. One long-established scenario, based upon early archaeological evidence, suggested that Africa’s earliest cattle derived from several introductions from Southwest Asia through the Nile Valley, or via the Horn of Africa. Based upon archaeofaunal remains retrieved in the late twentieth century, other archaeologists argued that an independent domestication of the African aurochs gave rise to Africa’s earliest domestic cattle. Up to now, the genetic data have also been controversial. This paper reviews the archaeological evidence and the scope of debate, and then focuses on the recent contributions of genetic research to clarifying these issues.  相似文献   
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Few people inside or outside government have had a greater impact on public policy in Australia than Ross Garnaut. His report in 1990 provided a blueprint for Australia's economic ‘engagement’ with Asia, whether or not one agreed with its underlying logic and analysis. The reception of his report on climate change in 2011 could hardly have been more different. Why is it that some ideas enjoy wide support from influential actors and are enthusiastically taken up by policymakers, while others struggle to gain traction, even when backed by government? This paper provides some possible answers to this puzzle by identifying factors that facilitate or obstruct the influence and impact of ‘policy entrepreneurs’.

在澳大利亚政府内外,对公共政策影响最大的人士莫过于郜若素了。他发表于1990年的报告,你同意其逻辑分析也好,不同意也罢,反正它都为亚澳经济关系提供了蓝图。他于2011年发表的环境报却得到迥然不同的反应。何以一些观点能够得到重要社会主体的广泛支持以及政策制定者的积极采纳,而另一些观点哪怕是有政府做后盾,也难得推广呢?本文通过寻找有利或有碍“政策专业户”发挥影响的因素,对这个问题作了回答。  相似文献   
38.
Conventional wisdom before the Vietnam War held that public opinion exerted no influence on U.S. foreign policy decisions. Scholars working in Vietnam's aftermath found episodic influence of public opinion on foreign policy, but missing in our understanding were longitudinal examinations of public opinion's influence on foreign policy. A number of post-Vietnam scholars subsequently revealed a long-term relationship between public opinion and defense spending. This study extends that work by analyzing responsiveness to public opinion in different foreign policy arenas by different government institutions, and by accounting for a critical variable not relevant in most previous studies: the end of the cold war. We construct a model explaining the influences of public opinion and the cold war on spending proposals for defense and foreign economic aid by the presidency, the House of Representatives and the Senate. Both public opinion and the end of the cold war exert direct influence on defense spending proposals by the presidency, while the Senate and the House respond primarily to public opinion inputs and the partisan composition of the Senate. In the case of foreign economic aid, the cold war's end gives occasion for increasing spending proposals, contrary to the public's expectation that the end of the cold war minimized the need for the U.S. to provide foreign economic assistance.  相似文献   
39.
Four miscellaneous artefacts, which do not correspond to the other major small finds groups, are also included in the Sharm assemblage. Whilst the gastropod shell is positively identified as Tonna luteostoma, the materials and function of the remaining objects are conjectural.  相似文献   
40.
Between ca. 6000 BC and ca. 500 BC, barley cultivation spread across the continent of Europe from the extreme south to the extreme north. Carbon-dating would suggest that this spread, and indeed the spread of crop cultivation generally, varied in its pace, with ‘delays’ at certain points along its route. Such delays in the spread of agriculture have been explained as resulting from the slow assimilation of agricultural practices by existing indigenous human populations or as the time taken for the crops to adapt to novel climatic conditions, such as altered temperature regimes and day-lengths. A mutant form of the photoperiod response gene, Ppd-H1, causes barley to be non-responsive to long days, while the wild-type responsive form allows plants to flower in response to long days. We sequenced this gene in 65 ‘historic’ barley accessions, from the late 19th and early 20th centuries, in order to explore the potential role of environmental adaptation in the spread of agriculture. We chose to use ‘historic’ material, to complement the richer patterns in extant genetic lines, by spreading the data range in both time and space. Our ‘historic’ barley data shows a latitudinal divide in the Ppd-H1 gene similar to that found in extant lines, but with clearer geographical resolution, and extending northwards into the Arctic Circle. We discuss the implications of our results in relation to the dynamics of agricultural spread across Europe.  相似文献   
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