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51.
分析了摆渡木马的工作原理和特点,提出了控制数据从计算机流向移动存储介质的解决方法。根据BLP模型的基本思想,提出了基于BLP模型的摆渡木马防御方案。在该方案中,根据内网或计算机中文件的重要程度,将文件分成不同等级;将用户对文件的访问权限也分成相应的不同等级;当用户对文件进行访问时,通过比较权限等级和文件等级来决定是否能读或写,读或写采用"下读上写"的策略。由于把移动存储介质的级别设为最低,所以该方案能有效的防止摆渡木马。  相似文献   
52.
Social media provide an online platform for enterprises to engage existing customers and attract new customers. Although social media can be easily set up at no cost, however, due to limited human and financial resources, many small businesses find it challenging to compete against large enterprises in social media use. While more and more small businesses have jumped on the bandwagon of social media in recent years, few studies investigated the social media strategies that can help small businesses to survive and even thrive against large competitors in the social media arena. Therefore, we studied 32 small pizzerias in a mid-size U.S. city in terms of their social media use for business. Our study found that small pizzerias emphasizing social media use on community relations and social responsibility tend to be more successful in attracting and engaging local customers. This study also sheds light on both effective strategies and successful practices of social media use by small pizzerias. The insights and recommendations identified from this study can help small businesses to enhance their social media competitiveness against large enterprises.  相似文献   
53.
Yelp, a social media site, undeniably has an influence on consumers' food choice in spite of its ability to reflect consumers' real voice being criticized. Since unhealthy food choices contribute to health problems, such as obesity and malnourishment, we attempted to examine these problems by better understanding consumers through health-related cues to action—a construct from the Health Belief Model (HBM)— on Yelp Honolulu's restaurant reviews. Our research revealed 13 main categories: Ingredient, Type of food, Taste, Lifestyle, Cooking, Option, Price, Portion, Well-being, Nutrition, Hygiene, Emotional attachment and indulgence, and Feeling. We argue that these categories may ultimately lead consumers to make healthier food choices. In search of the most appealing way to communicate with the target group, underlying concepts that derived from these categories can be tested. Marketers in food industry (or public health policy-makers) can craft their strategies for healthy food brands/products (or healthy eating scheme) based on the concept test research. Moreover, Yelp can apply these insights in the development of their algorithm and filter system in order to help consumers find healthy food if they wish to do so. Restaurants can also improve their strategy, menu, and communication execution to meet the growing demands of health conscious consumers.  相似文献   
54.
This paper outlines the major motivating factors concerning a novel collaborative project between Edinburgh College of Art and Edinburgh Virtual Environment Centre. The Tacitus project will investigate the use of multi-modal virtual environments, specifically, the haptic (touch) modality, with regards to the creative processes employed by designers working within the field of applied arts. The salient areas of research are described, and the methods by which information regarding these areas will be obtained are considered. Initial investigations have revealed a strong need to mimic the traditional applied artists' workspaces, with co-location of visual and haptic cues a priority.  相似文献   
55.
This essay begins with discussion of four relatively recent works which are representative of major themes and preoccupations in Artificial Life Art: ‘Propagaciones’ by Leo Nuñez; ‘Sniff’ by Karolina Sobecka and Jim George; ‘Universal Whistling Machine’ by Marc Boehlen; and ‘Performative Ecologies’ by Ruari Glynn. This essay is an attempt to contextualise these works by providing an overview of the history and forms of Artificial Life Art as it has developed over two decades, along with some background in the ideas of the Artificial Life movement of the late 1980s and 1990s.1 A more extensive study of the theoretical history of Artificial Life can be found in my paper ‘Artificial Life Art—A Primer’, in the Proceedings of DAC09 and also at http://www.ace.uci.edu/Penny. Excerpts from that essay are included here.   相似文献   
56.
纳微米聚合物作为一种新型的逐级调驱剂,可在油层深部发生物理和化学变化,实现液流改向。根据纳微米聚合物调驱渗流特点,此文建立了三维三相三组分纳微米聚合物调驱数学模型,考虑了对流扩散和调驱渗流特性,采用隐压、显饱、隐浓的差分方法求解数学模型,并编制了相应的数值模拟软件。对纳微米聚合物调驱矿场试验区进行了数值模拟研究,分析了纳微米聚合物浓度、段塞长度、段塞组合对开发指标的影响,并制定合理的注入方案,实施后达到了增油降水和提高采收率的目的,与数值模拟预测指标基本符合。  相似文献   
57.
分析和比较了几种典型的P2P流媒体模型,介绍了P2P流媒体不同模型常用的数据调度算法,并指出了基于应用层多播的树模型和基于Gossip协议的网状模型的区别,最后指出了P2P流媒体的研究方向。  相似文献   
58.
在这个越来越依赖计算机的时代,数据的重要性可想而知,对于存储计算机中的这些重要数据,它们是否万无一失呢?答案是否定的,由于种种原因导致数据丢失的现象时有发生。而对于每个曾有过数据丢失经历的人来说,这都算是一场噩梦。本文主要是基于WINDOWS下的数据恢复,通过数据恢复工具对存储介质中的数据进行恢复。  相似文献   
59.
ASF文件的特性使得用户可以通过编辑ASF文件来实现媒体流间的同步.  相似文献   
60.
The number of organizations using teamwork is increasing. In this context, group potency has emerged as a key construct in group research. Moreover, in the last decades, information and communication technologies (ICT) have allowed organizations to form virtual teams. Consequently, a considerable amount of research has analysed the functioning of virtual teams. We focus on intragroup conflict as a relevant antecedent of potency in computer-mediated communication groups. Specifically, the aim of this research is to examine the role of ICT in the relationship between intragroup conflict and group potency in a longitudinal study. A laboratory experiment was carried out comparing 44 groups working in two communication media (face-to-face and computer-mediated communication). The groups developed a project over a one-month period. The results show that communication media play a moderator role between intragroup conflict (relationship and task conflict) and group potency. Implications of these results are discussed.  相似文献   
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