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111.
文章从联通运营商WLAN业务发展的现状出发,对WLAN建设过程中存在的问题进行详细的分析和研究,根据原因提出有效的建设策略,并对3G网络的融合进行全面的阐述。 相似文献
112.
《Journal of computational science》2014,5(4):616-623
The major purpose of this paper is to transmit an existing video above a complete simulated video streaming architecture based on Network Simulator (NS2). Thanks to our architecture, the visual quality evaluation of the distributed streaming platform under various conditions is simplified. Indeed, the received video can be easily visualized using a classic video client or be compared using the Peak Signal-Noise Ratio (PSNR) value and the Structural SIMilarity (SSIM) value. In the case study, we compare adaptive video congestion strategies using a transcoder, Datagram Congestion Control Protocol (DCCP) and TCP-Friendly Rate Control (TFRC). 相似文献
113.
三网融合是下一代电信运营商网络发展趋势,本文分析研究了如何采用合波技术和GPON技术,实现在一张光纤到户网络上将语音、数据、广播电视网络的融合,使网络资源更加高效、合理的利用,降低运营成本,提高服务质量。 相似文献
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We consider the Robust Network Design problem, i.e. the problem of dimensioning the capacities on the edges of a graph to serve point-to-point traffic demands subject to uncertainty. The scope of the paper is to investigate when the cut condition is sufficient to guarantee the feasibility for such problem. 相似文献
118.
概述了SiP(系统封装)协调设计和PI解析:(1)协调工程(下);(2)电源供给电路;(3)SSD噪声;(4)旁路电容。 相似文献
119.
Infrastructure systems such as power and water supplies make up the cornerstone of modern society which is essential for the functioning of a society and its economy. They become more and more interconnected and interdependent with the development of scientific technology and social economy. Risk and vulnerability analysis of interdependent infrastructures for security considerations has become an important subject, and some achievements have been made in this area. Since different infrastructure systems have different structural and functional properties, there is no universal all-encompassing ‘silver bullet solution’ to the problem of analyzing the vulnerability associated with interdependent infrastructure systems. So a framework of analysis is required. This paper takes the power and water systems of a major city in China as an example and develops a framework for the analysis of the vulnerability of interdependent infrastructure systems. Four interface design strategies based on distance, betweenness, degree, and clustering coefficient are constructed. Then two types of vulnerability (long-term vulnerability and focused vulnerability) are illustrated and analyzed. Finally, a method for ranking critical components in interdependent infrastructures is given for protection purposes. It is concluded that the framework proposed here is useful for vulnerability analysis of interdependent systems and it will be helpful for the system owners to make better decisions on infrastructure design and protection. 相似文献
120.
Motivated by recent physics papers describing rules for natural network formation, we study an elliptic-parabolic system of partial differential equations proposed by Hu and Cai [13, 15]. The model describes the pressure field thanks to Darcy's type equation and the dynamics of the conductance network under pressure force effects with a diffusion rate D ≥ 0 representing randomness in the material structure. We prove the existence of global weak solutions and of local mild solutions and study their long term behavior. It turns out that, by energy dissipation, steady states play a central role to understand the network formation capacity of the system. We show that for a large diffusion coefficient D, the zero steady state is stable, while network formation occurs for small values of D due to the instability of the zero steady state, and the borderline case D = 0 exhibits a large class of dynamically stable (in the linearized sense) steady states. 相似文献