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101.
This paper studies the socialised affordances of social media in the processes of collective action, exploring the role of technology in the under‐researched area of civil society. We examine the case of Free Lunch for Children (FL4C), a charitable programme in China based on the microblogging platform, Weibo. Adopting the perspective of affordances‐for‐practice, we draw upon the collective action model to better understand the sociomaterial practices and social processes involving social media, and seek to address the ‘when’ and ‘how’ questions of affordances. The study generates theoretical and practical implications for understanding the role of social media in social transformation.  相似文献   
102.
非自愿移民政策作为一个适用于各个国家世界银行开发项目的指导性政策,被广泛运用于世行支持的国际项目中。随着“一带一路”战略的推进,我国水电企业参与海外发展项目建设的步伐明显加快。分析了世行有关非自愿移民政策与我国水电工程移民政策的异同,从中学习其有益的经验,为我国企业在国际基础设施项目建设中做好移民安置工作、提高工程效益提供借鉴。  相似文献   
103.
基于"六五"至"十二五"期间有关区域地下水演化的国家和省部级重点科技项目主要成果,对近30年来我国地下水演化研究的主要进展进行了综述。我国区域地下水演化研究主要集中在北方地区,项目选题的起源和立项的时代背景具有鲜明的时代性和社会重大需求驱动,包括华北和西北地区流域尺度地下水演化的国家重点项目研究,都是围绕国家目标或区域经济发展重大需求,及时揭示了气候变化和人类活动影响下区域地下水演化的关键科技问题,突显了重大科学研究的时代性和必要性。  相似文献   
104.
采用中国洪水预报系统的应用平台建立贝江勾滩水文站降雨径流模型洪水预报方案,利用系统自动进行模型参数的率定,该方案在精度的评定及实际应用中取得较满意的效果,解决了勾滩站长期没有洪水预报方案指导防洪的迫切的问题,为中国洪水预报在柳江流域的应用积累了经验.  相似文献   
105.
Currently, China’s e-commerce market is growing at an unprecedented pace, however, it is faced with many challenges, among which the trust fraud problem is the biggest issue. In this article, we use Taobao as an example and conduct a thorough investigation of the trust fraud phenomenon in China’s e-commerce market. We present the development history of trust fraud, summarize its unique characteristics, and explore the reasons why so many sellers commit fraud. We further propose a dynamic time decay trust model that aims to deter trust fraud by raising its cost and promote the growth of small and medium-sized sellers. The model utilizes detailed seller ratings as the data source, and incorporates a transaction amount weight, a time decay coefficient, and three trust factors in the calculation of trust. We test the model on real transaction data from Taobao, and the experimental results verify its effectiveness. Our proposed trust model yields a practical approach to online trust management not only in the Taobao market but also for other e-commerce platforms.  相似文献   
106.
介绍了国际标准书号的相关知识,分析了10位及13位中国标准书号的组成结构及其校验码的生成方法,并利用Delphi实现校验码生成及不同位数中国标准书号之间相互转换的程序。  相似文献   
107.
乘法器复用技术在滑窗FIR滤波处理中的运用   总被引:1,自引:0,他引:1  
随着超大规模集成电路的飞速发展,FPGA集成的硬件乘法器越来越多,内核时钟越来越快,使得FPGA在实时信号处理中得到广泛应用。介绍了FIR滤波运算的原理与硬件处理结构,通过乘法器的复用技术,解决了实现滑窗FIR滤波处理时,FPGA内部乘法器的高速运算与外部慢速数据率之间的矛盾。  相似文献   
108.
The impact of misregistration on SRTM and DEM image differences   总被引:2,自引:0,他引:2  
Image differences between Shuttle Radar Topography Mission (SRTM) data and other Digital Elevation Models (DEMs) are often performed for either accuracy assessment or for estimating vegetation height across the landscape. It has been widely assumed that the effect of sub-pixel misregistration between the two models on resultant image differences is negligible, yet this has not previously been tested in detail. The aim of this study was to determine the impact that various levels of misregistration have on image differences between SRTM and DEMs. First, very accurate image co-registration was performed at two study sites between higher resolution DEMs and SRTM data, and then image differences (SRTM–DEM) were performed after various levels of misregistration were systematically introduced into the SRTM data. It was found that: (1) misregistration caused an erroneous and dominant correlation between elevation difference and aspect across the landscape; (2) the direction of the misregistration defined the direction of this erroneous and systematic elevation difference; (3) for sub-pixel misregistration the error due solely to misregistration was greater than, or equal to the true difference between the two models for substantial proportions of the landscape (e.g., greater than 33% of the area for a half-pixel misregistration); and (4) the strength of the erroneous relationship with aspect was enhanced by steeper terrain. Spatial comparisons of DEMs were found to be sensitive to even sub-pixel misregistration between the two models, which resulted in a strong erroneous correlation with aspect. This misregistration induced correlation with aspect is not likely specific to SRTM data only; we expect it to be a generic relationship present in any DEM image difference analysis.  相似文献   
109.
Data services via wireless networks and mobile devices have experienced rapid growth worldwide. We investigated the factors influencing adoption of wireless mobile data services (WMDS) in China and tested our model for explaining adoption intentions there. We argued that individuals form their intention to adopt WMDS under the influence of wireless mobile technology, the social environment, personal innovativeness of IT, trust awareness, and the facilitating conditions. We examined the simultaneous effects of these five influences on beliefs in the context of wireless Internet data services via mobile phones. Survey data were collected from 1432 participants in several metro cities across China. The findings suggest that WMDS adoption intention in China is determined by consumers’ perceived usefulness and perceived ease of use of WMDS. Theoretical and practical implications are included in our paper.  相似文献   
110.
一种基于信息检索技术的网络新闻影响力分析方法   总被引:2,自引:0,他引:2  
杨伟杰  戴汝为  崔霞 《软件学报》2009,20(9):2397-2406
利用信息检索领域中的相关算法,分析研究通过信息检索相关技术得到的相关信息,建立了一个网络新闻影响力模型来定量地计算一则新闻的影响力,从而估计它对社会安全产生影响的程度.在对大量实验结果的统计分析中发现,此方法可以有效地对新闻文章进行排序,发现不同新闻类型中最值得关注的新闻,其结果与人的定性判断结果具有较高的一致性.  相似文献   
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