Search results for "BAND"

showing 10 items of 2610 documents

Large-Scale Available Bandwidth Measurements: Interference in Current Techniques

2011

The end-to-end available bandwidth of an Internet path is a desirable information that can be exploited to optimize system performance. Several tools have been proposed in the past to estimate it. However, existing measurement techniques were not designed for large-scale deployments. In this paper we show that current tools do not properly work where multiple probing processes share a portion of a path. We provide experimental evidence to quantify the impact of mutual interference between measurements. We further analyze the characteristics of popular tools, quantifying (i) the impact of mutual interference, (ii) the total overhead imposed to the network and (iii) the intrusiveness of the m…

Settore ING-INF/03 - TelecomunicazioniComputer Networks and Communicationsbusiness.industryComputer scienceSystem of measurementReal-time computingAvailable BandwidthProcess (computing)Interference (wave propagation)ScalabilityBandwidth (computing)Overhead (computing)The InternetElectrical and Electronic EngineeringbusinessDimensioning
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Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

Settore ING-INF/03 - TelecomunicazioniFree Space Optics (FSO) technologies for satellite communications offer several advantages: wide bandwidth high rate capability immunity to electromagnetic interference and small equipment size. Thus they are suitable for inter-satellite links deep space communications and also for high data rate ground-to-satellite/satellite-to-ground communications. Nevertheless FSO links suffer impairments that cause power signal degradation at the receiver. Scattering and absorption cause power signal attenuations predictable by suitable deterministic models. Optical turbulence causes random irradiance fluctuations which can generate signal fading events and can thereby only be predicted by statistical models. Attenuation and fading events can corrupt FSO links and so it would be recommended to add mitigation error codes on the communication link. FSO channel can be described as an erasure channel: fading events can cause erasure errors. We have identified in rateless codes (RCs) a suitable solution to be employed in FSO links. RCs do not need feedback and they add a redundant coding on the source data that allows the receiver to recover the whole payload despite erasure errors. We implemented two different of rateless codes: Luby Transform (LT) and Raptor. We analyzed their performances on a simulated turbulent GEO FSO downlink (1 Gbps - OOK modulation) at a 106 μm wavelength and for different values of zenith angles. Assuming a plane-wave propagation and employing Hufnagel-Valley we modeled the downlink using: 1) a temporal correlated channel model based on Gamma-Gamma probability distribution and 2) an irradiance covariance function that we converted on a time function using Taylor frozen eddies hypothesis. Our new channel model is able to simulate irradiance fluctuations at different turbulence conditions as it will be shown in the full paper. We will also report performance results of LT and Raptor codes at overhead range varying between 0 and 50% and for different values of source packets.Settore ING-INF/01 - Elettronica
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A Fog-Based Application for Human Activity Recognition Using Personal Smart Devices

2019

The diffusion of heterogeneous smart devices capable of capturing and analysing data about users, and/or the environment, has encouraged the growth of novel sensing methodologies. One of the most attractive scenarios in which such devices, such as smartphones, tablet computers, or activity trackers, can be exploited to infer relevant information is human activity recognition (HAR). Even though some simple HAR techniques can be directly implemented on mobile devices, in some cases, such as when complex activities need to be analysed timely, users’ smart devices can operate as part of a more complex architecture. In this article, we propose a multi-device HAR framework that exploits the fog c…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniExploitComputer Networks and CommunicationsComputer sciencebusiness.industryBandwidth (signal processing)Activity tracker020206 networking & telecommunicationsCloud computing02 engineering and technologyActivity recognitionHuman–computer interactionHuman activity recognition mobile crowdsensing fog computing0202 electrical engineering electronic engineering information engineering020201 artificial intelligence & image processingSmart environmentbusinessMobile deviceWearable technologyACM Transactions on Internet Technology
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Bando di concorso: profili sostanziali e problemi di giurisdizione

2022

Il contributo fornisce una sintesi delle principali questioni che riguardano il bando di concorso nell’impiego pubblico privatizzato, mostrando attenzione alle clausole immediatamente lesive rappresentate dai requisiti discriminatori, in presenza dei quali si prospetta la possibilità di utilizzare lo strumento di tutela previsto dall’art. 28 del d.lgs. n. 150/2011, in alternativa al ricorso al giudice amministrativo. Con riguardo al riparto di giurisdizione vengono analizzati i principali nodi problematici in materia di progressioni verticali e di scorrimento delle graduatorie. The essay summarises most relevant issues on competition announcement in privatised public employment law, with a …

Settore IUS/07 - Diritto Del LavoroCompetition announcement discrimination art. 28 legislative decree no. 150/2011 vertical progressionsBando di concorso discriminazione art. 28 d.lgs. 150/2011 progressioni verticali
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I limiti di applicabilità del principio di eterointegrazione dei bandi.

2007

I limiti di applicabilità del principio di eterointegrazione dei bandi.

Settore IUS/10 - Diritto AmministrativoI limiti di applicabilità del principio di eterointegrazione dei bandi.
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Contatti culturali, identità e popolamento nel territorio imerese

2016

Il lavoro prende in considerazione il problema dei rapporti tra coloni greci e comunità indigene nel territorio di Himera, sulla base dei risultati della prospezione archeologica condotta per tre decenni nelle valli dei fiumi Imera settentrionale, Torto e S. Leonardo. Vengono esaminati gli elementi di cultura materiale che permettono di definire i modi dell'interazione culturale tra coloni e indigeni, nonché di ricostruire i paesaggi politici, socio-economici e il paesaggio del sacro nelle diverse aree indagate e nei diversi comprensori. La ricerca infatti permette di delineare, oltre alle usuali organizzazioni insediative e agricole della chora politiké e della éremos chora, anche articola…

Settore L-ANT/09 - Topografia AnticaSettore L-ANT/07 - Archeologia ClassicaThis work focuses on the problem of cultural contacts between Greek colonists and indigenous communities in the territory of Himera based on the results of the archaeological survey conducted for three decades in the valleys of the northern Imera Torto and S. Leonardo rivers. The elements of material culture that enable us to define the ways of cultural interaction between settlers and indigenous peoples as well as to reconstruct the political socio-economic and sacred landscapes in the various districts investigated are examined. In fact the research allows to outline in addition to the usual settlement and agricultural organizations of chora politiké and éremos chora articulated areas within the territory of Himera and to understand the landmarks of the rural settlement alongside the presence of highland settlements . Therefore the center-periphery approach is abandoned for a more articulated analysis demonstrating different forms of settlement and cultural contact in the three river valleys of the Himera hinterland.
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Filologia degli scarti: il caso dell'"Abandonnée"

This papaer shed light on the supposed composition of an alternative version, now lost, of the adagio "Anch'io dischiuso un giorno" of Abigaille's aria in the secondo act of Nabucco by Verdi. We can hypothesise that the piece in question was actually composed by Verdi for Giuseppina Strepponi, and that it was subsequently transformed by the composer into the French-language chamber song "L'abandonnée", published in 1849.

Settore L-ART/07 - Musicologia E Storia Della MusicaOpera Studies Verdi Nabucco Strepponi Chamber Music L'abandonnée
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Nomi d’arte e soprannomi di cantautori, rapper e band della scena musicale siciliana

2019

Nowadays the names and bynames of pop-groups and musicians are more and more characterized by multiple, differentiated onomaturgical solutions which allow us to explore and comprehend current linguistic and cultural trends as well as the metalinguistic awareness/competence of authors and «users» of the music industry. On the one hand, as far as the national and international scenario is concerned, many names are based on a sort of game of mirrors: from personal names to place names and street names, from sign names to brand names, a lot of linguistic material «rebounds” on the names of singers and bands. On the other hand, as far as the Sicilian dialect song context is concerned, most names…

Settore L-FIL-LET/12 - Linguistica ItalianaDialectal Songs Musicians’ and Bands’ Names Rappers’ Nicknames
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Autonomic Regulation In Autism Spectrum Disorders

2017

Introduction: The sinactive developmental model provides suggests a different way for the brain study by observing the children behavior. In all neurodevelopmental disorders, we can observe autonomic alteration comprising sleep disorders, meal behaviour alteration and self-regulatory impairment. These alterations/impairment are very frequent in autism spectrum disorders (ASD) (1-12). Aim of the present preliminary study is the assessment of metabolic rate in children affected by ASD. Material s and methods. 5 males affected by ASD aged 7-10 years (mean age 6.73±3:39), were recruited. The average score at the ADOS scale was 12.24 (SD± 3.29). The control group consisted of 5 males typically d…

Settore M-PSI/04 - Psicologia Dello Sviluppo E Psicologia Dell'EducazioneSenseWear ArmbandAutonomic regulationMedicine (all)Autism spectrum disorderAutism spectrum disorders; Autonomic regulation; SenseWear Armband; Medicine (all)Settore MED/39 - Neuropsichiatria Infantile
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Behavioral changes on severe obese persons after gastric banding. Preliminary hypothesis

2008

Behavioral changes, gastric banding

Settore MED/18 - Chirurgia GeneraleBehavioral changes gastric banding
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