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31.
作为社会化媒体的重要类型,微博已经成为继新闻网站、论坛、博客之后,网络舆论生成的主要载体,"微博问政"成为热点和趋势,政务微博也成为政府信息公开、发布权威信息、提供公共服务、加强政民互动、引导网络舆论的重要平台。随着政务微博的快速发展,一系列新问题、新挑战也逐步显现。本文结合国土资源部政务微博的现状,就如何使用政务微博为民服务,提高政务微博应用水平,促进政务微博的健康发展,提升政府公信力,提出了对策建议。  相似文献   
32.
In the United States, both scholars and practitioners have repeatedly emphasized the importance of “issue framing” for garnering public support for climate change policy. However, the debate frequently overlooks the importance of counter frames. For every framing attempt by advocates of climate policy, there will be a counter frame by the opponents of climate policy. How do counter frames influence the effectiveness of issue framing as a communication strategy? To answer this question, we report results from a survey experiment on a nationally representative sample of 1000 Americans on clean energy policy, a key policy issue in the public debate on climate change in the United States. Overall, we find that different combinations of positive and negative frames have remarkably little effect on support for clean energy policy. A follow-up on-line survey experiment with a convenience sample of 2000 Americans suggests that the counter frames are responsible for undermining the effects of the original frames.  相似文献   
33.
薛杭  赵烽帆  荣华 《中国地震》2022,38(3):425-431
2022年9月5日12时52分,四川省甘孜州泸定县发生 MS6.8地震,造成重大人员伤亡,引起社会公众的广泛关注。突发事件的信息发布和舆情引导越来越受到党和政府的高度重视,相关信息公开效率的影响甚至决定了事件处置的舆情发展。本研究以中国地震台网中心为舆情引导主体,对四川泸定 MS6.8地震舆情进行分析研究,总结舆情引导经验,探讨突发地震舆情引导对地震部门有效开展震后应急的促进作用,以期为今后的防震减灾新闻宣传工作带来启示和思考。  相似文献   
34.
Cardiovascular disease (CVD) is the number one cause of death in the state of Texas. In order to develop effective healthcare policies to combat CVD, it is essential to understand what types of communities are most affected. In this paper, we develop a classification scheme to segment high-prevalence communities based on selected social and demographic characteristics. We find that while many high-prevalence areas reflect traditional relationships between socioeconomic deprivation and poor health outcomes, a subset of more affluent communities in Texas are also affected. This suggests the importance of tailored approaches to prevention that account for this diversity among high-prevalence neighborhoods.  相似文献   
35.
Public policy frequently is utilised as a medium to facilitate or restrict access to public space, and to privilege economic priorities. In this context urban arts festivals are used as a means to generate dominant narratives of place and use of public space. Urban arts festivals generate spaces of spectacle and wonder, and are often used as marketing strategies to revitalise urban economies and differentiate cities one from another on the global stage, engendering a commodification of place. The present paper explores this tension through an examination of the role of urban arts festivals in spatial politics. White Night Melbourne is the first Australian iteration of the Nuit Blanche International, an international network of all-night arts festivals. It is used as a case study to explore the impact of an urban arts festival on the spatial politics of Melbourne. A theoretical basis is established using the frame of Guy Debord's ([1967] 1994) The Society of the Spectacle, as well as the concepts of ‘assemblage’ and ‘expressivity’.  相似文献   
36.
Accurate pesticide exposure estimation is integral to epidemiologic studies elucidating the role of pesticides in human health. Humans can be exposed to pesticides via residential proximity to agricultural pesticide applications (drift). We present an improved geographic information system (GIS) and remote sensing method, the Landsat method, to estimate agricultural pesticide exposure through matching pesticide applications to crops classified from temporally concurrent Landsat satellite remote sensing images in California. The image classification method utilizes Normalized Difference Vegetation Index (NDVI) values in a combined maximum likelihood classification and per-field (using segments) approach. Pesticide exposure is estimated according to pesticide-treated crop fields intersecting 500 m buffers around geocoded locations (e.g., residences) in a GIS. Study results demonstrate that the Landsat method can improve GIS-based pesticide exposure estimation by matching more pesticide applications to crops (especially temporary crops) classified using temporally concurrent Landsat images compared to the standard method that relies on infrequently updated land use survey (LUS) crop data. The Landsat method can be used in epidemiologic studies to reconstruct past individual-level exposure to specific pesticides according to where individuals are located.  相似文献   
37.
Abstract

A series of meetings of two ‘Citizen Panels’ were held to explore public perceptions of off-shore carbon dioxide (CO2) capture and storage (CCS). In addition, a face-to-face survey of 212 randomly selected individuals was conducted. We found that, on first hearing about CCS in the absence of any information on its purpose, the majority of people either do not have an opinion at all or have a somewhat negative perspective. However, when (even limited) information is provided on the role of CO2 storage in reducing CO2 emissions to the atmosphere, opinion shifts towards expressing slight support for the concept.

Support depends, however, upon concern about human-caused climate change, plus recognition of the need for major reductions in CO2 emissions. It also depends upon CCS being seen as just one part of a wider strategy for achieving significant cuts in CO2 emissions. A portfolio including renewable energy technologies, energy efficiency, and lifestyle change to reduce demand was generally favoured. CCS can be part of such a portfolio, but wind, wave, tidal, solar and energy efficiency were preferred. It was felt that uncertainties concerning the potential risks of CCS had to be better addressed and reduced; in particular the risks of accidents and leakage (including the potential environmental, ecosystem and human health impacts which might result from leakage).  相似文献   
38.
PKI安全认证模型的分析与研究   总被引:2,自引:0,他引:2  
在开放式网络环境中,实现诸多安全服务,最重要的问题之一就是要解决网络中各实体之间的安全认证问题.安全认证模型作为网络安全技术的重要前提和基础,正日益成为网络信息安全领域研究的焦点.在对传统PKI认证模型分析的基础上,提出了一种全新的PKI安全认证模型,着重研究了PKI安全认证模型的体系结构,提出了适合于国家级的PKI安全认证模型.这为构建国家级PKI安全认证模型的研究提供了一个有价值的新思路.  相似文献   
39.
信任对市场、经济和社会的繁荣与发展具有重要作用。信任作为经济社会发展的内生变量,与区域经济发展、市场化进程之间存在着相互影响、互为因果的关系。中国新兴加转轨的双重制度环境加剧了区域信任度的差异,这种差异更多是区域经济发展和市场化进程的结果而不是原因。通过对中国大陆省际不均衡的区域经济发展、市场化进程和信任水平进行比较分析,发现较高的区域经济发展水平和与之协调的市场化进程导致较高的区域信任度,较低的区域经济发展水平和超前的市场化进程导致较低的区域信任度。  相似文献   
40.
马海涛  周春山  刘逸 《地理研究》2012,31(6):1057-1065
网络演化是演化经济地理学研究的重要内容和新近热点之一。在当前的理论探讨中主要强调路径依赖和惯例对网络演化的强化作用,对于信任这个关键要素缺乏深入探讨。本文通过深度访谈和问卷调查相结合的方法,对比金融危机前后广东省纺织服装行业生产网络的空间结构,揭示信任与生产网络演化之间的互动机制。研究发现:信任是维系生产网络稳定性的基本要素之一,信任的强弱程度主要受合作类型(市场关系)、地理接近(空间关系)和社会文化接近根植性(社会关系)等因素影响。金融危机作为一种负面外部冲击,重构了广东省服装行业的生产网络。在这个过程中,较强信任关系的网络连结(潮汕地区)得以保留,并在危机过后进一步强化;而部分较弱信任关系的网络连结(珠三角地区)发生断裂,且在经济回暖之后被潮汕地区的网络所取代。  相似文献   
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