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41.
孟茹 《山西气象》2006,(3):31-32
2006年5月27日,全国第一个新一代气象数据卫星接收站在山西省气象信息中心投入业务试运行,该系统采用的是D V B传输协议。DVB-S(Digital Video Broadcastby Satellite)气象数据接收站在山西省的成功安装,标志着我国新一代气象数据卫星广播系统建设工作拉开了序幕。该系统的业务化运行将大大增加气象信息的数据量,提供高质量的流媒体广播,为提高天气预报准确率和气象服务时效奠定坚实的基础。目前新系统运行一切正常。  相似文献   
42.
A filed experiment was conducted continuously for three days, and the velocity variation was measured using coda wave interferometry. The measurement error is estimated to be around 10^-4, which coincides well with the theoretical error. The velocity variation during this period is up to 10^-3. The relationship between velocity variation and changes in air temperature, barometric pressure and solid earth tide was analyzed with linear least square fitting. The velocity has no dependence on air temperature, but displayed change of the order of 10^-6 - 10^-7 when the barometer or earth tide changed one Pa.  相似文献   
43.
高密度电法探测地下空洞   总被引:1,自引:0,他引:1  
简要介绍了高密度电法的基本原理及其特点,结合探查地下空洞实例,说明高密度电法寻找地下空洞的利弊。  相似文献   
44.
With its longstanding history and interest in issues of landscape and representation, geographers are ideally positioned to analyze the relationship between media, identity and place in media. What is missing, however, is a grounded understanding of the dynamics of the locally produced politics of representation and, in particular, how these representations are perceived by different members of the audience. This paper briefly explores the nexus of race, news production and news consumption through an analysis of interviews with racialized journalists (journalists who identified as members of minority racial groups) and a focus group conducted with self-identified Iranian Canadians. The paper looks specifically at two themes that emerged in the empirical material: the contamination of memory and the creation of colonized memory media-spaces for some participants in the focus group, and the nature of racialized silences in the newsroom. I suggest that geographies of news might well be understood as a complex, interactive process of the production of meaning between both producer and consumer, where news content, ethics, roles and values are negotiated through multiple social contexts.  相似文献   
45.
Sarah F. Ives 《GeoJournal》2009,74(3):245-255
Using a discussion of South African soap operas, I will place the idea of visuality in a discourse analysis that incorporates a feminist epistemological lens, or an epistemology that integrates reflexivity and an acknowledgment of the dialogic nature of visual media. Through this discussion, I will examine the possibilities that dialogism provides for unpacking and exploring the politics of imperfect translation between the visual and the textual. These methodological interventions, I argue, will help enrich discussions of the visual’s role in the contested realm of geographic imaginations and move beyond the distanced position of the masculine gaze.
Sarah F. IvesEmail:
  相似文献   
46.
Wilkinson microwave anisotropy probe (WMAP) has provided us with the highest resolution all-sky maps of the cosmic microwave background (CMB). As a result of thermal Sunyaev–Zel’dovich effect, clusters of galaxies are imprinted as tiny, poorly resolved dips on top of primary CMB anisotropies in these maps. Here, I describe different efforts to extract the physics of intracluster medium (ICM) from the sea of primary CMB, through combining WMAP with low-redshift galaxy or X-ray cluster surveys. This finally culminates at a mean (universal) ICM pressure profile, which is for the first time directly constrained from WMAP 3 year maps, and leads to interesting constraints on the ICM baryonic budget.  相似文献   
47.
Predictions that work in fields such as computer programming, architecture, and graphic design will be globally sourced have raised the specter of job losses among skilled workers in high wage economies. One of the most interesting cases tied to this controversy is that of so-called “runaway” motion picture and television production from the traditional center of entertainment media production in Los Angeles to non-US satellite production centers. Although runaway production is an old complaint in the entertainment media industries, the production location decisions of media entertainment firms since the mid-1990s look considerably different than those in the 1980s when a similar alarm was raised. Among the critical differences are: (1) the location of an expanded range of production activities in regions outside the “headquarters” location of Los Angeles; (2) the ability of transnational firms to access multiple, self-organized and networked pools of skilled labor in production locations outside Los Angeles; and (3) the expanded role of the sub-national state in reducing the overall production costs of transnational firms, including those attendant to their use of skilled labor pools. The current controversy provides an opportunity to consider how transnational firms use international out-sourcing to address their need for high-skilled and specialized labor in the production process. It also contributes to the on-going theoretical debate over how transnational firms are combining the advantages to be derived from territorial agglomeration with those of substitutability of labor skills in multiple locations.  相似文献   
48.
利用北京昌平南口地区的地震活动性、震源参数与介质特性等对南口山前断裂进行断层分段,结果表明该断层各段的地震学特征差异明显,与地质学手段所得到的部分结果是一致的  相似文献   
49.
China's social media platform, Sina Weibo, like Twitter, hosts a considerable amount of big data: messages, comments, pictures. Collecting and analyzing information from this treasury of human behavior data is a challenge, although the message exchange on the network is readable by everyone through the web or app interface. The official Application Programming Interface (API) is the gateway to access and download public content from Sina Weibo and is used to collect messages for all mainland China. The nearby_timeline() request is used to harvest only messages with associated location information. This technical note serves as a reference for researchers who do not speak Mandarin but want to collect data from this rich source of information. Ways of data visualization are presented as a point cloud, density per areal unit, or clustered using Density‐Based Spatial Clustering of Applications with Noise (DBSCAN). The relation of messages to census information is also given.  相似文献   
50.
People’s behavior on online social networks, which store geo-tagged information showing where people were or are at the moment, can provide information about their offline life as well. In this paper we present one possible research direction that can be taken using Flickr dataset of publicly available geo-tagged media objects (e.g., photographs, videos). Namely, our focus is on investigating attractiveness of countries or smaller large-scale composite regions (e.g., US states) for foreign visitors where attractiveness is defined as the absolute number of media objects taken in a certain state or country by its foreign visitors compared to its population size. We also consider it together with attractiveness of the destination for the international migration, measured through publicly available dataset provided by United Nations. By having those two datasets, we are able to look at attractiveness from two different perspectives: short-term and long-term one. As our previous study showed that city attractiveness for Spanish cities follows a superlinear trend, here we want to see if the same law is also applicable to country/state (i.e., composite regions) attractiveness. Finally, we provide one possible explanation for the obtained results.  相似文献   
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