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41.
本文以历年《中国体育事业统计年鉴》中的积累数据为研究对象,通过对各类统计数据表的分析,运用数据库技术和软件工程方法,确定表的结构,建立年鉴数据库;研究运用c#语言设计开发基于网络的c/s模式前端客户端,对数据库进行添加、删除、修改、查询、导出等相关操作,实现对《中国体育事业统计年鉴》数据的网络化管理。 相似文献
42.
Eric C. Chi Liuyi Hu Arvind K. Saibaba Arvind U. K. Rao 《Journal of computational and graphical statistics》2019,28(1):36-47
We consider the problem of performing matrix completion with side information on row-by-row and column-by-column similarities. We build upon recent proposals for matrix estimation with smoothness constraints with respect to row and column graphs. We present a novel iterative procedure for directly minimizing an information criterion to select an appropriate amount of row and column smoothing, namely, to perform model selection. We also discuss how to exploit the special structure of the problem to scale up the estimation and model selection procedure via the Hutchinson estimator, combined with a stochastic Quasi-Newton approach. Supplementary material for this article is available online. 相似文献
43.
Although many brands develop mobile applications (apps) to build relationships with consumers, most branded apps fail to retain consumers’ loyalty. This study examines the facilitation of consumer loyalty toward branded apps (continuance intention, in-app purchase intention, and word-of-mouth intention) from the dual-route perspective. One route is the affective (relationship) route, where brand benefits (functional benefits, experiential benefits, symbolic benefits, and monetary benefits) drive parasocial interactions between consumers and the brand, which, in turn, influences branded app loyalty. The other route is the utility route, where system characteristics (system quality and information quality) affect perceived usefulness, which, in turn, facilitates branded app loyalty. An online survey was conducted, and the research model was empirically tested using partial least squares structural equation modeling. The findings support the dual-route perspective according to which both affective and utilitarian paths facilitate branded app loyalty. The key theoretical contribution of this study is that it moves beyond the utilitarian path and finds the affective (relationship) path to give a more complete picture of the facilitation of consumer loyalty in the branded app context. A strategy is provided to suggest to practitioners how to design branded apps to facilitate consumer loyalty. 相似文献
44.
45.
In this sequel to our previous study of the entropic and energetic costs of information erasure [N.G. Anderson, Phys. Lett. A 372 (2008) 5552], we consider direct overwriting of classical information encoded in a quantum-mechanical memory system interacting with a heat bath. Lower bounds on physical costs of overwriting – in both “single-shot” and “sequential” overwriting scenarios – are obtained from globally unitary quantum dynamics and entropic inequalities alone, all within a referential approach that grounds information content in correlations between physical system states. A heterogeneous environment model, required for consistent treatment of sequential overwriting, is introduced and used to establish and relate bounds for various cases. 相似文献
46.
我国正迈入快速城市化建设过程中,运用GIS技术手段来解决城市规划过程中的城市化建设进程信息整合管理,对于提高城市规划信息整合效率、避免重复建设、重叠规划、一库多建等城市规划问题有着积极意义。 相似文献
47.
近年来,无线传感网以其特殊的军事、商业前景而广泛受到关注,与传统有线网络相比,无线传感网有着自己的优势和特性,而在信息社会,信息安全无疑是研究的一个重要方向。至此,国内外学者对无线传感网的安全性进行了大量研究,尤其是在密钥分配这一方面,首先对密钥分配的概念进行阐述,针对无线传感网自身特点,选取了较为合适的分布式密钥分配方案,分析了几种方案的基本原理,并分别从安全性、通信计算开销和效率等角度分析了其优势和不足,最后,在此基础上进行总结与展望。 相似文献
48.
Maria Elizabeth Grabe Ozen Bas Irene Ingeborg van Driel 《The Journal of communication》2015,65(2):300-319
Education‐based knowledge gaps are well‐documented across countries, media platforms, and content. Without exception, knowledge is measured through words not images. Given the centrality of sight in the natural history of Homo sapiens, the extraordinary visual acuity of humans, and the proliferation of screen‐based visual media environments in contemporary life, an experiment was conducted to test the knowledge gap visually. Participants watched 8 audiovisual news stories. Simple recognition of story details and comprehension of that information were tested in verbal and visual modalities. Results offered the first confirmation of the knowledge gap in visual terms. Yet, gaps were significantly smaller employing visual than verbal measures, pointing to the need for continued efforts to develop visual measures for future memory studies. 相似文献
49.
夜视战场环境视觉传感信息的实时获取是跟踪夜视战场图像处理分析的前提,针对夜视战场环境的复杂特征,设计了夜视战场环境视觉传感信息采集系统,分析了系统的总体结构,系统硬件主要包括视觉传感器、传感器控制卡和扩展卡、图像采集与存储以及信号调理电路,给出了系统采集节点的程序设计流程以及传感信息采集的具体程序代码实现过程。实验结果说明,所设计系统可有效采集到夜间军事战场中的传感信息,并且具有较高的采集精度。 相似文献
50.