Search results for "Overhead"
showing 10 items of 101 documents
ARQ parameters for VoIP in IEEE 802.16 networks
2009
IEEE 802.16 standard defines two data retransmission mechanisms. HARQ provides fast retransmissions in cost of slightly increased overhead. On the contrary, ARQ has less overhead in cost of bit longer delays. It is therefore often used with BE connections. In addition to delay tolerant applications, BE can also be used for real-time services. Therefore, in this paper we analyze the ARQ mechanism and provide guidelines on how to set the ARQ parameters to achieve a good balance between the VoIP delay and packet loss.
Neighbor discovery and resource allocation for device-to-device communication
2014
Masteroppgave i Informasjons- og kommunikasjonsteknologi IKT590 Universitetet i Agder 2014 Device-to-Device (D2D) communication has attracted lots of attention as one of the most advanced wirelesscommunication technologies which allows access to services offered by nearby devices bypassing the BaseStation (BS). The potential advantages of this direct communication paradigm include high data rate, networkoffloading and range extension, as well as commercial proximity services and social networking. From the UserEquipments (UEs) and BS perspective, additional protocol overhead and discovery resource are required forD2D links. In such a context, neighbor discovery and resource allocation appro…
A Survey on Privacy in Decentralized Online Social Networks
2018
Decentralized Online Social Networks (DOSNs) have recently captured the interest of users because of the more control given to them over their shared contents. Indeed, most of the user privacy issues related to the centralized Online Social Network (OSN) services (such as Facebook or Google+) do not apply in the case of DOSNs because of the absence of the centralized service provider. However, these new architectures have motivated researchers to investigate new privacy solutions that allow DOSN’s users to protect their contents by taking into account the decentralized nature of the DOSNs platform. In this survey, we provide a comprehensive overview of the privacy solutions adopted by…
A study on the use of bare buried conductors in an extended interconnection of earthing systems inside a MV network
2005
In the field of electrical safety an important topic is the transmission of voltages, during an earth fault, inside an extended interconnection of local earthing systems. The paper presents a study, with reference to the MV networks, about those systems where the interconnection between the earth electrodes of the electrical installations is carried out using bare buried conductors. Starting from the description of the circuital model of a bare buried conductor interconnecting together the earth electrodes of two MV/lv substations, the mathematical model of the whole interconnected earthing system is found. Finally, the results of some simulations, giving the distribution of the fault curre…
Multithreaded Translation of Ptolemy II Designs on Multicore Platforms
2008
Ptolemy II is an open source environment for system design and test based on component data flow. This paradigm tries to make parallel systems more deterministic and understandable. In this work we propose a technique to translate designs developed with Ptolemy II, into multithreaded Java implementations on multicore platforms. We have chosen Java mainly because Ptolemy II is implemented in Java and then we get direct code reuse. The counterpart is a certain amount of overhead that we expect to be less relevant as Java runtime environment will evolve. The main goals are to produce efficient parallel simulators and software devices with competitive performance level. We show by means of an e…
Fault-Tolerant Application Mapping on to ZMesh topology based Network-on-Chip Design
2020
This paper proposes Particle Swarm Optimization (PSO) based fault-tolerant application mapping on to ZMesh topology based Network-on-Chip (NoC) design. Permanent faults in application cores has been considered and performed application mapping using PSO. The major contribution of this paper is to find out the best position for the spare core to be placed in the network using PSO. Experimentations have been carried out by scaling the ZMesh network size and percentage of network faults. The results show that the proposed approach leads to minimum overhead in communication cost over fault-free result.
Cooperative communication design with distributed code allocation in a clustered network
2011
A major challenge for cooperative communication in distributed networks is to coordinate relay transmissions without introducing too much overhead. Targeting a clustered network, we propose a novel cooperative communication scheme including channel quality based relay selection and distributed space-time code allocation in this paper. Both analysis and simulations are carried out to investigate the performance of the proposed cooperative scheme, in terms of packet delivery rate, throughput and energy efficiency, under different channel conditions and network density.
Optimal Integration of Hybrid Supercapacitor and IPT System for a Free-Catenary Tramway
2019
The aim of the paper is the study of an optimal integration of a supercapacitor-based storage system and inductive power transfer system for the free-catenary operation of a tramway. Starting from the definition of the topology of inductive power transfer system, we propose and analyze a design procedure for the pads of the inductive power system. In the second part of the paper, an optimal integration strategy for the correct size of on-board supercapacitors and the power of the inductive energy transfer are proposed. The results obtained by means of numerical simulations are discussed. © 2018 IEEE.
High-Voltage Injuries by Contact With Overhead Lines: Case Reports of Two Young Girls
2021
Abstract High-voltage burn injuries are rare in the pediatric age group, but can lead to devastating, severe sequelae. We present the cases of two young girls who suffered high-voltage burn injuries due to direct contact with overhead power lines. Both patients came from difficult psychosocial backgrounds. The injuries resulted in severe long-term consequences and functional deficits.
Link adaptation with combined optimal frame size and rate selection in error-prone 802.11n networks
2008
In error-prone channel with low SNRs, the network throughput may drop significantly if the packet length becomes too large. On the other hand, too much protocol overhead will be introduced if the packet length is too small. In this paper, we study this tradeoff and propose an adaptive frame size algorithm for A-MPDU in 802.11n networks, which can maximize the throughput by selecting the optimized frame length under different channel conditions. When used together with rate selection, the network throughput can be further improved. Both analytical model and simulation results are presented, demonstrating that our algorithm outperforms the fixed length transmission scheme in 802.11n networks …