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91.
兰燕  刘珊红  戴晓爱 《四川测绘》2007,30(4):155-158
本文针对国内公共交通拥堵、效率低的现状,提出了基于移动通信/GPS/GIS技术的智能公交系统的解决方案,该系统能在很大程度上缓解目前公共交通拥堵的现状。本文主要介绍了智能公交系统的关键技术以及系统构成。  相似文献   
92.
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   
93.
Public perceptions of climate change are traditionally measured through surveys. The exploding popularity of social networks, however, presents a new opportunity to research the spatiotemporal pattern of public discourse in relation to natural and/or socio-economic events. Among the social networks, Twitter is one of the largest microblogging services. The architecture of Twitter makes the question “what's happening?” the cornerstone of information exchange. This inspired the notion of using Twitter users as distributed sensors, which has been successfully employed in both the natural and social sciences. In 2012 and 2013, we collected 1.8 million tweets on “climate change” and “global warming” in five major languages (English, German, Russian, Portuguese, and Spanish). We discuss the geography of tweeting, weekly and daily patterns, major news events that affected tweeting on climate change, changes in the central topics of discussion over time, the most authoritative traditional media, blogging, and the most authoritative organizational sources of information on climate change referenced by Twitter users in different countries. We anticipate that social network mining will become a major source of data in the public discourse on climate change.  相似文献   
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