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71.
互联网正在迅速地成为世界经济增长和社会进步的重要动力。本文首先分析了全球互联网技术扩散的地理格局,研究表明发达国家和发展中国家的数字鸿沟依然明显。接着分析了政治因素对互联网技术扩散的影响因素,并通过计量的手段探究了社会经济因素的效果,结果表明人均产出变量是互联网渗透率区域变差的决定因素。在此基础上探讨了互联网的这种地理格局对未来地区社会经济发展的潜在影响。最后提出了超越数字鸿沟的基本举措:加快经济发展、重视互联网基础设施和教育投资和增进国际间的合作。  相似文献   
72.
Undoubtedly watersheds and their limiting groundwater divides are not steady but change. Nevertheless the temporal and spatial scales of the changes are seldom explored and rarely can be quantified. The Lake Stechlin region offers the exceptional chance to study the transient dynamics of catchments, the movement of subsurface water divides and their disappearance and reappearance. Based on long‐term data of surface water and groundwater levels a computer model delivers illustrative pictures of the dynamics of natural water bodies. A simple analytically derived criterion for the occurrence of groundwater divides shows remarkable coincidence with observations and with the output from the numerical model. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
73.
Measuring Spatial Differences of Informatization in China   总被引:1,自引:1,他引:0  
As the wide application of new Information and Communication Technologies (ICTs) shows, the world is moving fast to- wards an information age. Since China was first connected to the Internet in 1994, the development of ICTs in China and around the world has been astonishingly fast, and yet there is a clear 'digital divide' among different regions in China. Although Chinese geogra- phers have paid attention to regional differences in informatization, they usually employ a limited number of indicators, mainly focusing on the Intemet. In fact, infi~rmatization is a much broader concept, covering not only the lntemet, but also mobile phones as well as user ability. In the light of these considerations, this study provides a comprehensive examination of the development of informatization and its spatial differences in China. First, based on a literature review, the paper identifies 29 preliminary indicators for measuring informa- tization, and employs prin,-ipal components analysis and the fuzzy analytic hierarchy process to streamline them into 12 indicators to form an ICTs Developmen: Index (ID1). Second, by using the data from provincial statistical yearbooks and the China Internet Network Information Center, the paper calculates the 1191 of each mega-region and each province in 2000-2010, and measures the changing spa- tial differences in the development of informatization in China. Lastly, the paper quantifies the relationship between informatization and economic growth. The empirical results show that the IDI of the western and central China has been increasing faster than that of the coastal region, indicating that the digital divide in China has been narrowing.  相似文献   
74.
开展1∶1万地质灾害易发区图编制工作,可为地质灾害防治规划、土地利用总体规划、地质灾害危险性评估、建设工程选址等提供可靠的资料,对做好地质灾害防治工作具有重要意义。本文以泰顺县为例,采用地质灾害综合危险性指数法划分地质灾害易发区,总结分析地质灾害易发程度分区评价的经验,为大比例尺易发区图编制作一些有益的探讨。  相似文献   
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