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Average Delay (average + delay)

Distribution by Scientific Domains

Engineering	50%
Mathematics and Statistics	33%

Selected Abstracts

Minimisation of end-to-end delay in reconfigurable WDM networks using genetic algorithms

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 8 2009
Ramón J. Durán Barroso
A new genetic algorithm (GA) is proposed to design logical topologies for wavelength-routed optical networks (WRONs) with the objective of minimising the end-to-end delay. Two versions of the algorithm, called D-GALD (Delay-optimised Genetic Algorithm for Logical topology Design), have been developed. The first one minimises the average end-to-end delay of the packets transported by the network, while the second one minimises the average delay of the most delayed traffic flow. By means of a simulation study, we show that the logical topologies designed by D-GALD support more than 50 per cent higher traffic load,without causing network instability,than those ones designed by other heuristics. Moreover, the utilisation of D-GALD leads to reductions of up to 15 per cent in the average end-to-end delay and around 30 per cent in the average end-to-end delay of the most delayed traffic flow. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Increasing the throughput of HomePNA

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 7 2008
Aurelio Amodei Jr
Abstract In this paper we propose a new medium access mechanism for HomePNAv2 and HomePNAv3 standards. This mechanism uses a priority aggregation mechanism to avoid collisions, increasing these protocols throughput. Furthermore, this mechanism does not require modifying standards, since it can be implemented over their actual MAC sublayers. Simulation results show that the proposed mechanism is able to increase the throughput up to 44% for HomePNAv2 and 36% for HomePNAv3. Moreover, we also show how this mechanism affects network delay, analyzing average delay and jitter for all protocols presented. Copyright © 2008 John Wiley & Sons, Ltd. [source]

An energy-efficient multipath routing protocol for wireless sensor networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 7 2007
Ye Ming Lu
Abstract The energy consumption is a key design criterion for the routing protocols in wireless sensor networks. Some of the conventional single path routing schemes may not be optimal to maximize the network lifetime and connectivity. In this paper, we propose a distributed, scalable and localized multipath search protocol to discover multiple node-disjoint paths between the sink and source nodes. We also propose a load balancing algorithm to distribute the traffic over the multiple paths discovered. We compare our proposed scheme with the directed diffusion, directed transmission, N -to-1 multipath routing, and the energy-aware routing protocols. Simulation results show that our proposed scheme has a higher node energy efficiency, lower average delay and control overhead than those protocols. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Analysis of a finite-buffer bulk-service queue with discrete-Markovian arrival process: D-MAP/Ga,b/1/N

NAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 4 2003
M.L. Chaudhry
Abstract Discrete-time queues with D-MAP arrival process are more useful in modeling and performance analysis of telecommunication networks based on the ATM environment. This paper analyzes a finite-buffer discrete-time queue with general bulk-service rule, wherein the arrival process is D-MAP and service times are arbitrarily and independently distributed. The distributions of buffer contents at various epochs (departure, random, and prearrival) have been obtained using imbedded Markov chain and supplementary variable methods. Finally, some performance measures such as loss probability and average delay are discussed. Numerical results are also presented in some cases. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 345,363, 2003. [source]

k -Splittable delay constrained routing problem: A branch-and-price approach

NETWORKS: AN INTERNATIONAL JOURNAL, Issue 1 2010
Jérôme Truffot
Abstract Routing problems, which include a QoS-based path control, play a key role in broadband communication networks. We analyze here an algorithmic procedure based on branch-and-price algorithm and on the flow deviation method to solve a nonlinear k -splittable flow problem. The model can support end-to-end delay bounds on each path and we compare the behavior of the algorithm with and without these constraints. The trade-off between QoS guarantees and CPU time is clearly established and we show that minimizing the average delay on all arcs will yield solutions close to the optimal one at a significant computational saving. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010 [source]

Juvenile Myoclonic Epilepsy , an experience from north western India

ACTA NEUROLOGICA SCANDINAVICA, Issue 1 2001
A. Panagariya
Objectives, The clinical data on cases of Juvenile Myoclonic Epilepsy (JME) were analysed. Response to initial small dosages (lower than usual) of sodium valproate and further lower maintenance dosages in patients who were seizure free for 2 years on drug were assessed. Material and methods, Seventy-six patients who were diagnosed to have Juvenile Myoclonic Epilepsy on definite criteria were studied. All patients were put on sodium valproate in dosages (lower than usual) for initial control and further lower maintenance dosage and response evaluated. Results, The clinical profile was found to be similar as in other parts of India. There was a female preponderance and average delay of 4.9 years in final diagnosis. Forty-eight (63.1%) patients showed good control on 15 mg/kg/day dosages of sodium valproate. After a seizure free interval of 2 years, 58% of patients could be maintained on small dosages ranging from 3,5 mg/kg/day to 6,8 mg/kg/day. Conclusion, The majority of JME patients responded well not only to sodium valproate in dosages lower than usually prescribed but required very small dosages for maintenance after a seizure free period of 2 years. [source]