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161.
Paul Claval 《GeoJournal》2000,51(1-2):73-81
Capital cities reflect the nature and organization of the states they control. Their functional role is higher in centralized systems, societies where the state is the source of all legitimacy, and countries using Continental Law. It is lower in federal systems, pillarized societies and countries, which are ruled according to a Common Law. The symbolic status of capital cities is higher when the state is the source of all legitimacy, lower in consociationalist societies. Theses processes were responsible for the development of two types of political capital cities and one type of economic and cultural capital cities during the nineteenth century. A partial standardization of the functions and statuses of capital cities occurred later. The European Union is neither a state nor a super-state since its main responsibilities are still in the economic field, it lacks a huge administrative bureaucracy and does not have definitive territorial limits. The European Union has officially three capital cities, Strasbourg, Luxembourg and Brussels. The really important one is Brussels. Its functions are nevertheless quite different from those of national capital cities during the first half of the twentieth century. European capital cities are thriving because most of them managed to become economic metropolises. The result is that the European Union has a complex and rapidly evolving system of capital cities. 相似文献
162.
余维法 《广东海洋大学学报》2009,29(2)
汶川抗震救灾精神是以爱国主义为核心的民族精神的大弘扬;是以人为本的民本精神和以改革创新为核心的时代精神的大展示;弘扬汶川抗震救灾精神,全面建设小康社会:必须树立崇高理想,坚定必胜信念;自力更生,艰苦奋斗;解放思想,实事求是;团结协作,顾全大局;心系群众,患难与共。 相似文献
163.
季节性冻融对土壤水分的作用及其在农业生产中的意义 总被引:20,自引:1,他引:20
正冻土体冻结缘的水势梯度导致非冻结土中的水分向冻结土体迁移,使融解后的土壤水分含量显著提高。然而,土壤水分增加的数量决定于冻结前土壤水分的剖面分布状况。根据田间试验结果,利用土壤冻融作用对土壤剖面水分的再分布,储水灌溉时间可以提前至9月下旬至10月中旬,灌溉定额可以降低至60m3/亩,甚至40m3/亩。灌溉后及时地进行地面覆盖保墒措施,可以改善较早灌溉和低定额灌溉条件下在播种期的土壤墒情,显著提高作物的出苗率。 相似文献
164.
土壤无机氮素的损失主要是铵氮的挥发损失和硝氮的反硝化和淋失.土壤水分和氮素含量的增加,都将增加氮肥淋失的潜在威胁,如处置不当,获得高产可能需要以环境的污染为代价.节水条件下土壤无机氮素的损失量有所减少,但是氮素利用效率也同时受到了土壤水分状况的限制.探讨了作物产量、氮素损失和农业生产要素(水分、氮素)实际投入量之间的关系,建立了节水条件下土壤氮素损失和环境评价概念型模型,通过在北京水利科学研究所永乐店灌溉试验站3年的试验资料对模型进行了参数求解及校验. 相似文献
165.
会徽是一种行业标识、一段历史烙印、一个学术品牌,它作为一种信息载体,以简单、形象、易识别的图像表达了学术团体的学术宗旨和使命,同时彰显了学术团体的工作目标、学术精神等科学文化内涵。笔者等以中国地质学会会徽为分析案例,通过与东西方几个代表性国家地质学会的文化宗旨与会徽内涵的比较,探讨会徽在学会科学文化建设中的作用。 相似文献
166.
167.
《The Professional geographer》2013,65(3):267-271
Integration in human geography is achieved through multidimensional research or by the study of a variety of aspects of a whole. Giddens's structuration theory provides a new theoretical framework for integrative study in human geography in its attempt to connect individuals and societies, context and composition, time and space. Integrative studies in geography have focused on space (regional geography), time (historical geography) and society (time-geography). Structurationist analysis in geography can put society, space, or society and space at its focus. Thrift's spatial structurationist theory may lead to a new theoretically-based regionalism. On the other hand, integration at one level or between several elements may entail disintegration, at another level or element respectively. 相似文献
168.
《The Professional geographer》2013,65(3):233-236
The application of geographic concepts and techniques to solving human problems is gaining new strength as a dimension of American geography. The nature of this trend is being shaped by a concern for relevance and educational change. Adoption of this approach has many implications for the individual geographer, as well as for the discipline. Some possible negative and positive aspects of the trend are suggested. 相似文献
169.
《Urban geography》2013,34(7):683-704
Despite a major road construction program, the pace of traffic circulation in Moscow has slowed to less than half the average speed recorded for 1991. One problem is the rapid growth in the number of vehicles, but even more important, as shown in this study, are the cultural and political dimensions of driving and automobile ownership, or automobility. Currently, some specifically Russian driving practices exacerbate the situation. Yet there are many drivers who are eager to collaborate with City Hall in the effort to alleviate congestion. It is argued here that these driver-citizens are emerging publics, people who are creating a civil society without specifically meaning to do so. Mayor Luzhkov acknowledges public opinion, but persists in attempting to solve traffic and parking problems "from above" by constructing more facilities without inviting public participation in planning. These efforts appear unlikely to succeed as long as the public is excluded from mobility governance. 相似文献
170.
随着新一轮科技产业变革深入发展,全球专利转移活动日趋活跃。借助复杂网络分析和负二项式回归分析,探讨中国对外专利引进网络和专利输出网络的时空演化特征,研究发现(:1)中国与其他国家和地区之间的专利转移网络日益稠密,参与专利转移的国家或地区数量不断增加,且专利转移网络表现出明显的空间异质性。欧洲、北美和东亚形成的“三足鼎立”格局逐步取代了欧美长期主导中国对外技术交流的“两极”格局。(2)在对外技术转移网络中逐渐形成台湾省、香港特别行政区、中国内地三大核心枢纽。中国内地技术进步明显,逐渐成为网络最大的核心,其专利引进规模一直大于专利的输出规模,但专利输出的增长速度更快。台湾省一直以技术输出为主导;香港特别行政区则一直扮演着技术中介的作用,技术输出和引进较为均衡;而澳门特别行政区的作用并不明显。(3)从跨国专利转移规模的影响因素中发现,加大研发投入和高新技术产品出口可以缩小技术差距以促进专利转移,畅通的技术通道确保了专利转移的持续进行,国民经济水平也存在一定的积极影响,但地理邻近性的影响并不显著。 相似文献