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    Spectrum Trading: An Abstracted Bibliography

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    This document contains a bibliographic list of major papers on spectrum trading and their abstracts. The aim of the list is to offer researchers entering this field a fast panorama of the current literature. The list is continually updated on the webpage \url{http://www.disp.uniroma2.it/users/naldi/Ricspt.html}. Omissions and papers suggested for inclusion may be pointed out to the authors through e-mail (\textit{[email protected]})

    E³DOAS: balancing QoE and energy-saving for multi-device adaptation in future mobile wireless video delivery

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    Smart devices (e.g. smartphones, tablets, smart-home devices, etc.) have become important companions to most people in their daily activities, and are very much used for multimedia content exchange (i.e. video sharing, real-time/non-real-time multimedia streaming), contributing to the exponential increase in mobile traffic over the current wireless networks. While the next generation mobile networks will provide higher capacity than the current 4G systems, the network operators will face important challenges associated with the outstanding increase of both video traffic and user expectations in terms of their levels of perceived quality or Quality of Experience (QoE). Furthermore, the heterogeneity of mobile devices (e.g. screen resolution, battery life, hardware performance) also impacts severely the end-user QoE. In this context, this paper proposes an Evolved QoE-aware Energy-saving Device-Oriented Adaptive Scheme (E3DOAS ) for mobile multimedia delivery over future wireless networks. E3DOAS makes use of a coalition game-based rate allocation strategy within the multi-device heterogeneous environment, and optimizes the trade-off between the end-user perceived quality of the multimedia delivery and the mobile device energy-saving. Testing has involved a prototype of E3DOAS, a crowd-sourcing-based QoE assessment method to model non-reference perceptual video quality, and an energy measurement testbed introduced to collect power consumption parameters of the mobile devices. Simulation-based performance evaluation showed how E3DOAS outperformed other state of the art multimedia adaptive solutions in terms of energy saving, end-to-end Quality of Service (QoS) metrics and end-user perceived quality

    Modeling Context-Adaptive Energy-Aware Security in Mobile Devices

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    As increasing functionality in mobile devices leads to rapid battery drain, energy management has gained increasing importance. However, differences in user’s usage contexts and patterns can be leveraged for saving energy. On the other hand, the increasing sensitivity of users’ data, coupled with the need to ensure security in an energy-aware manner, demands careful analyses of trade-offs between energy and security. The research described in this thesis addresses this challenge by 1)modeling the problem of context-adaptive energy-aware security as a combinatorial optimization problem (Context-Sec); 2) proving that the decision version of this problem is NP-Complete, via a reduction from a variant of the well-known Knapsack problem; 3) developing three different algorithms to solve a related offline version of Context-Sec; and 4) implementing tests and compares the performance of the above three algorithms with data-sets derived from real-world smart-phones on wireless networks. The first algorithm presented is a pseudo-polynomial dynamic programming (DP)algorithm that computes an allocation with optimal user benefit using recurrence of the relations; the second algorithm is a greedy heuristic for allocation of security levels based on user benefit per unit of power consumption for each level; and the third algorithm is a Fully Polynomial Time Approximation Scheme (FPTAS) which has a polynomial time execution complexity as opposed to the pseudo-polynomialDP based approach. To the best of the researcher’s knowledge, this is the first work focused on modeling, design, implementation and experimental performance
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