199 research outputs found
Sleep Period Optimization Model For Layered Video Service Delivery Over eMBMS Networks
Long Term Evolution-Advanced (LTE-A) and the evolved Multimedia Broadcast
Multicast System (eMBMS) are the most promising technologies for the delivery
of highly bandwidth demanding applications. In this paper we propose a green
resource allocation strategy for the delivery of layered video streams to users
with different propagation conditions. The goal of the proposed model is to
minimize the user energy consumption. That goal is achieved by minimizing the
time required by each user to receive the broadcast data via an efficient power
transmission allocation model. A key point in our system model is that the
reliability of layered video communications is ensured by means of the Random
Linear Network Coding (RLNC) approach. Analytical results show that the
proposed resource allocation model ensures the desired quality of service
constraints, while the user energy footprint is significantly reduced.Comment: Proc. of IEEE ICC 2015, Selected Areas in Communications Symposium -
Green Communications Track, to appea
A Hierarchical Communication Architecture for Oceanic Survelliance Applications
The interest in monitoring applications using underwater sensor networks has been growing in recent years. The severe communication restrictions imposed by underwater channels make that efficient monitoring be a challenging task. Though a lot of research has been conducted on underwater sensor networks, there are only few concrete applications to a real-world case study. In this work, hence, we propose a general three tier architecture leveraging low cost wireless technologies for acoustic communications between underwater sensors and standard technologies, Zigbee and Wireless Fidelity (WiFi), for water surface communications. We have selected a suitable Medium Access Control (MAC) layer, after making a comparison with some common MAC protocols. Thus the performance of the overall system in terms of Signals Discarding Rate (SDR), signalling delay at the surface gateway as well as the percentage of true detection have been evaluated by simulation, pointing out good results which give evidence in applicability’s favour
Bounds for the relative n-th nilpotency degree in compact groups
The line of investigation of the present paper goes back to a classical work
of W. H. Gustafson of the 1973, in which it is described the probability that
two randomly chosen group elements commute. In the same work, he gave some
bounds for this kind of probability, providing information on the group
structure. We have recently obtained some generalizations of his results for
finite groups. Here we improve them in the context of the compact groups.Comment: 9 pages; to appear in Asian-European Journal of Mathematics with
several improvement
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