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31.
Ghana was one of the first countries in sub-Saharan Africa to be connected to the Internet, yet has very low Internet usage (5.3 users per 100 inhabitants). A qualitative study including in-depth interviews with ISPs explored Internet diffusion in Ghana. Findings suggest that due to Ghana's inefficient and outdated fixed-line infrastructure, universal Internet access goals might not be achievable through fixed-line technologies. Rather, wireless technologies may be more efficient. However, high access costs continue to be a barrier. Policy options to encourage widespread deployment of wireless broadband and cost reduction are presented as suggestions for further research. These include using universal service funds to expand the national backbone with an open access high capacity wireless backbone to reach unserved and underserved areas, reducing license and regulatory fees for the wireless industry to encourage coverage and capacity expansion, and mandatory infrastructure sharing to reduce cost.  相似文献   
32.
The Internet of Things (IoT) is a novel paradigm that connects the pervasive presence around us of a variety of things or objects to the Internet by using wireless/wired technologies to reach desired goals. Since the concept of the IoT was introduced in 2005, we see the deployment of a new generation of networked smart objects with communication, sensory and action capabilities for numerous applications, mainly in global supply chain management, environment monitoring and other non-stress environments. This paper introduces the IoT technology for use in the emergency management community. Considering the information required for supporting three sequential and distinct rhythms in emergency response operations: mobilization rhythm, preliminary situation assessment rhythm, and intervention rhythm, the paper proposes a modified task-technology fit approach that is used to investigate how the IoT technology can be incorporated into the three rhythms and enhance emergency response operations. The findings from our research support our two hypotheses: H1: IoT technology fits the identified information requirements; and H2: IoT technology provides added value to emergency response operations in terms of obtaining efficient cooperation, accurate situational awareness, and complete visibility of resources.  相似文献   
33.
DDS是一种数字波形合成技术,具有频率转换速度快、频率分辨率高、相位噪声低等优良性能,因此利用DDS作为可变参考源是比较理想的。本文采用DDS作为参考源驱动PLL频率合成器,实现了一个用于S波段遥测接收机的DDS/PLL频率合成器,同时对DDS/PLL频率合成器的输出特性进行了理论分析,并给出了实验结果。  相似文献   
34.
The paper focuses on third generation wireless technologies and on alternative technologies for wireless local area networks. The authors present the evolutionary migration path from second to third generation systems. Technological, economic and behavioral factors related to decision-making towards the migration are proposed. As an example, the paper studies the case of the national incumbent operator of India. It analyzes qualitatively the migration problem from the perspective of the operator, the equipment manufacturer and the users. For the quantitative analysis, real options are used to value the investment decisions. The analysis suggests that the initial (sunk) investment cost, the average revenue per user, the growth of the subscriber base and the volatility of the markets are the key factors in the investment process.  相似文献   
35.
本文采用基于ZigBee网络协议无线传感器网络能够保证数据无线传输的可靠性、准确性弥补了传统的有线网络的不足与缺陷,提高了煤矿井下瓦斯监测的精确性,并随着矿井生产过程中新工作面的开采和旧巷道的废弃,只需要增加、减少或移动无线传感器节点,无线传感器网络的拓扑结构基本不受其影响。同时也提高了煤炭生产安全性,加快煤矿信息化、智能化进程。  相似文献   
36.
Despite making significant investments in enhancing the customer service experience, long-term customer loyalty remains an elusive dream for many service providers. Particularly in the telecommunications industry, switching providers even from within continuous contract relationships is easy and companies struggle to retain their customers. Trust and value are considered cornerstones of long-term relationships, so it is perhaps surprising that previous research on how relationship age and usage level actually affect value, trust and loyalty is inconclusive. The current research is set in the telecommunications services field and draws on a large-scale survey undertaken in Finland. The findings support the contention that perceived value relates positively to loyalty, and that trust mediates that relationship. Surprisingly, in the telecommunications industry, increasing relationship age and usage level strengthen neither value and loyalty nor the links between trust and loyalty. The results may be explained by the unique characteristics of the highly competitive mobile telecommunications sector, and confirm the view that loyalty does not pay without strategies that value long-term customers and thereby build trust with new customers.  相似文献   
37.
多接口多信道的无线Mesh网络容易受到其它相同频率信道的无线干扰,导致网络性能的下降。针对临时环境组网的特点,采用高通信量链路干扰最小的原则,提出新的信道分配模型及算法,经验证该算法对网络性能有一定程度的提升。  相似文献   
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39.
系统分析了从电子商务到移动商务的结构性变迁,并对移动商务--21世纪的机遇与挑战及其发展前景进行了研究﹑探讨及展望。  相似文献   
40.
《Telecommunications Policy》2014,38(11):1024-1034
This study examines if, in addition to increasing lobbying expenditure amounts, corporations in the broadcast and wireless industries are also attempting to change lobbying strategies in order to gain competitive advantage. This study examines possible changes in lobbying strategies though the lens of institutional isomorphism, a mechanism of institutional theory. Using institutional isomorphism, the study examines if the broadcast and wireless industries have altered lobbying strategies in the face of competition. This examination is conducted through the construction and analysis of an original data set of lobbying expenditures for the broadcast and wireless industries from 1998 to 2012.  相似文献   
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