Search results for "NETWORKS"
showing 10 items of 3260 documents
Is TCP Packet Reordering Always Harmful?
2004
IP networks do not provide any guarantee that packets belonging to the same flow are delivered in the correct order. Out-of-order reception of packets was commonly considered due to pathological network conditions (such as link failures, etc.). However, it has been shown that packet reordering is a phenomenon which occurs even in normal network operation, due to a number of link-level and/or router-level implementation features, such as local parallelism and load balancing. Packet reordering is intuitively considered as a negative phenomenon, which may severely affect TCP traffic performance since it is expected to cause inefficient usage of the available link bandwidth and is expected to i…
Using Discharge Abstracts to Evaluate a Regional Perinatal Network: Assessment of the Linkage Procedure of Anonymous Data
2008
To assess the Burgundy perinatal network (18 obstetrical units; 18 500 births per year), discharge abstracts and additional data were collected for all mothers and newborns. In accordance with French law, data were rendered anonymous before statistical analysis, and were linked to patients using a specific procedure. This procedure allowed data concerning each mother to be linked to those for her newborn(s). This study showed that all mothers and newborns were included in the regional database; the data for all mothers were linked to those for their infant(s) in all cases. Additional data (gestational age) were obtained for 99.9% of newborns.
Plasma PLTP (phospholipid-transfer protein): an emerging role in ‘reverse lipopolysaccharide transport’ and innate immunity
2011
Plasma PLTP (phospholipid-transfer protein) is a member of the lipid transfer/LBP [LPS (lipopolysaccharide)-binding protein] family, which constitutes a superfamily of genes together with the short and long PLUNC (palate, lung and nasal epithelium clone) proteins. Although PLTP was studied initially for its involvement in the metabolism of HDL (high-density lipoproteins) and reverse cholesterol transport (i.e. the metabolic pathway through which cholesterol excess can be transported from peripheral tissues back to the liver for excretion in the bile), it displays a number of additional biological properties. In particular, PLTP can modulate the lipoprotein association and metabolism of LPS …
La mesura de l'ús de les llengües en els mitjans telemàtics
2020
La consolidació de l'entorn digital i totes les seues modalitats de comunicació ha ampliat les possibilitats d'interacció i, per tant, els àmbits d'ús de les llengües. Com a adaptació a aquesta nova realitat, en aquesta aproximació metodològica plantegem la combinació de diferents tècniques no reactives: explotació de fonts secundàries, observació sistemàtica, i mystery shopping. Les fonts d'observació directa ens permeten mesurar de manera efectiva l'ús de les llengües en la comunicació telemàtica. Els autors ho han aplicat específicament en l'administració local i en empreses de serveis. En l'àmbit administratiu, a més, això ens ha servit per a desenvolupar un índex global de presència de…
Coarse-Grained Barrier Trees of Fitness Landscapes
2016
Recent literature suggests that local optima in fitness landscapes are clustered, which offers an explanation of why perturbation-based metaheuristics often fail to find the global optimum: they become trapped in a sub-optimal cluster. We introduce a method to extract and visualize the global organization of these clusters in form of a barrier tree. Barrier trees have been used to visualize the barriers between local optima basins in fitness landscapes. Our method computes a more coarsely grained tree to reveal the barriers between clusters of local optima. The core element is a new variant of the flooding algorithm, applicable to local optima networks, a compressed representation of fitnes…
Performance evaluation of different techniques to estimate subjective quality in live video streaming applications over LTE-Advance mobile networks
2018
Abstract Current mobile service providers are offering Gigabit Internet access over LTE-Advanced networks. Traditional services, such as live video streaming, over wired networks are feasible on these networks. However different aspects should be taken into account due to the fast changing network conditions as well as the constrained resources of the mobile phones, in order to provide a good subjective video quality in terms of Mean Opinion Score (MOS). Our goal is to estimate and predict this subjective metric without information or reference from the original video, known as Non Reference approach. This approach is important for the Service Provider from a practical point of view, becaus…
A Comparative Facebook Content Analysis between Romanian and Western European Airline Carriers
2014
This research aims to investigate the different social media strategies adopted by the airline companies from two European regions. In the attempt to land more customers on their social media runway, drive more sales from social media content, increase customer satisfaction through a high response rate or increase their brand awareness, the airlines combine creativity and high-quality ideas to better promote their products and services to customers all around the globe. The paper analyses the content (number of fans, posts, number of likes, the dynamics of comments, response rate) on the Facebook pages of Tarom, Blue Air, Wizz Air, Lufthansa, Austrian Airlines, KLM International and Air Eur…
Robust L1 fixed-order filtering for switched LPV systems with parameter-dependent delays
2015
Abstract This paper is concerned with the L1 fixed-order filtering problem for a class of switched linear parameter-varying (LPV) systems in which the system matrices and the time delays are dependent on the real-time measured parameters. The authors׳ attention is concentrated on designing the fixed-order filter that guarantees the filtering error system to be exponentially stable and to satisfy a prescribed L1 disturbance attenuation level with respect to all amplitude-bounded disturbances. Based on the switching logic with the minimum average dwell time (ADT), the delay-dependent L1 performance criterion for the switched LPV systems is first established. As there exists coupling between a…
On stability and stabilization of singular uncertain Takagi-Sugeno fuzzy systems
2014
This paper deals with the problem of robust stability and robust stabilization for a class of continuous-time singular Takagi-Sugeno fuzzy systems. Sufficient conditions on stability and stabilization are proposed in terms of strict LMI (Linear Matrix Inequality) for uncertain T-S fuzzy models. In order to reduce the conservatism of results developed using quadratic method, an approach based on non-quadratic Lyapunov functions and S-procedure is proposed. Illustrative examples are given to show the effectiveness of the given results Refereed/Peer-reviewed
Observer-based H∞ control on stochastic nonlinear systems with time-delay and actuator nonlinearity
2013
Abstract In this paper, an observer-based H ∞ controller is designed for a class of extended Markov jump systems subject to time-delay and actuator saturation nonlinearity. Gradient linearization procedure is employed to describe such nonlinear systems by several linear Markov jump systems. Next, a mode-dependent Lyapunov function is constructed for these linear systems, and a sufficient condition is derived to make them stochastically stable, and then, a continuous gain-scheduled approach is applied to design a continuous nonlinear observer-based controller on the entire extended nonlinear jump system. A simulation example is given to illustrate the effectiveness of developed techniques.