Search results for " Error."

showing 10 items of 1034 documents

Validation of a temperature emissivity separation hybrid method from airborne hyperspectral scanner data and ground measurements in the SEN2FLEX fiel…

2008

This paper presents an assessment of the performance of a hybrid method that allows a simultaneous retrieval of land-surface temperature (LST) and emissivity (LSE) from remotely-sensed data. The proposed method is based on a synergistic usage of the split-window (SW) algorithm and the two-temperature method (TTM) and combines the advantages of both procedures while mitigating their drawbacks. The method was implemented for thermal channels 76 (10.56 µm) and 78 (11.72 µm) of the Airborne Hyperspectral Scanner (AHS), which was flown over the Barrax test site (Albacete, Spain) in the second week of July 2005, within the framework of the Sentinel-2 and Fluorescence Experiment (SEN2FLEX) field c…

Set (abstract data type)ScannerMean squared errorThermalSeparation (aeronautics)EmissivityGeneral Earth and Planetary SciencesEnvironmental scienceHyperspectral imagingField campaignRemote sensingInternational Journal of Remote Sensing
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Rete Sismica Nazionale e sua performance di localizzazione: una valutazione tramite il metodo SNES

2010

Settore GEO/11 - Geofisica ApplicataSettore GEO/10 - Geofisica Della Terra Solidaottimizzazione rete sismica errori di localizzazione
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Numerical scheme influence on Pseudo Dynamic tests results

2008

Settore ICAR/09 - Tecnica Delle CostruzioniPseudo-dynamic tests errors numerical algorithms non-linear systems
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An intelligent way to predict the building thermal needs: ANNs and optimization

2022

The evaluation of the energy performance of existing or new buildings is a fundamental action to guarantee the feasibility of a project and the achievement of the minimum efficiency requirements. In general, the determination of the thermal loads of a building is carried out via software but their use requires adequate knowledge of physical phenomena and therefore the presence of an expert user. Furthermore, the resolution can be difficult to implement and can require high computational costs; all conditions that can influence the success of a project. Based on these considerations, this work proposes an alternative solution to traditional calculation tools, which in a simple and effective …

Settore ING-IND/11 - Fisica Tecnica AmbientaleArtificial IntelligenceGeneral EngineeringArtificial Neural Network Thermal energy demand Forecast method Sensitivity analysis Statistical error analysisComputer Science ApplicationsExpert Systems with Applications
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Assessment of indoor illuminance and study on best photosensors' position for design and commissioning of Daylight Linked Control Systems. A new meth…

2018

Abstract Artificial lighting systems have to ensure appropriate illuminance with high energy efficiency according to best design practice and technical standards. These aims can be tackled, by incorporating a Daylight linked control system. However, the system behaviour is strongly influenced by several factors and, in particular, by the sensors' position. Indeed, very often the illuminance on work-plane is not fully correlated with illuminance measured by the photo-sensor used to control the luminaires. This fact leads to wrong information for the Daylight linked control systems affecting its efficacy. The artificial intelligence of Neural Networks can be exploited to provide a method for …

Settore ING-IND/11 - Fisica Tecnica AmbientaleArtificial neural networkMean squared errorComputer science020209 energyMechanical Engineering0211 other engineering and technologiesProcess (computing)IlluminanceControl engineeringIndoor artificial lighting Energy efficient lighting Intelligent lighting control Artificial neural network lighting measures reliability02 engineering and technologyBuilding and ConstructionPollutionIndustrial and Manufacturing EngineeringGeneral EnergyPosition (vector)Control system021105 building & construction0202 electrical engineering electronic engineering information engineeringDaylightElectrical and Electronic EngineeringSet (psychology)Civil and Structural Engineering
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An improved five-parameter model for photovoltaic modules

2010

This paper presents a new five-parameter model capable of analytically describing the I–V characteristic of a photovoltaic module for each generic condition of operative temperature and solar irradiance. The parameters of the equivalent electrical circuit are extracted by solving a system of equations based on data commonly issued by manufacturers in standard rating conditions with a trial and error process. The procedure, which does not require any special equations solver, can be easily coded into a short software routine using simple languages and finds the solution of the system of equations with the desired accuracy without needing to be guided towards solutions starting from fitted in…

Settore ING-IND/11 - Fisica Tecnica AmbientaleOperating photovoltaic currentRenewable Energy Sustainability and the Environmentbusiness.industryComputer sciencePhotovoltaic systemVisual Basic for ApplicationsI–V characteristicSolverSystem of linear equationsTrial and errorOne-diode equivalent circuitSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialslaw.inventionSoftwareSolar energyPhotovoltaic modulelawElectrical networkEquivalent circuitbusinessFive-parameter modelSimulationSolar Energy Materials and Solar Cells
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Advances in Strain Gauge Measurement on Composite Materials

2010

This article gives an overview on the application of strain gauge techniques to the analysis of the strains in composite materials. The orthotropic behaviour of the composite influences the performance of strain gauges that are calibrated for use on isotropic materials. The article considers therefore the typical topics of the strain gauge technology applied to composites with particular reference to the compensation of thermal output, the measurement of the coefficients of thermal expansion, the determination of the strain and stress state, the influence of the misalignment error, the reinforcement effect, the determination of the stress intensification factor, the analysis of residual str…

Settore ING-IND/14 - Progettazione Meccanica E Costruzione Di Macchinecomposite materials electrical resistance strain gauges experimental mechanics misalignment errors thermal output compensation
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Analisi di sicurezza nella procedura di protonterapia oculare applicata presso i Laboratori del Sud dell’INFN di Catania

2017

A partire dal 2002, l’Azienda Ospedaliera Universitaria “Policlinico Vittorio Emanuele” di Catania ha effettuato il trattamento di circa 350 pazienti affetti da neoplasie oculari mediante fasci di protoni prodotti con il ciclotrone disponibile presso i Laboratori nazionali del Sud (LNS). Tale impianto viene utilizzato per attività di ricerca nell’ambito della fisica sperimentale, per cui è stato necessario modificare le caratteristiche del fascio, rendendolo idoneo alle applicazioni cliniche. Il lavoro di ricerca ha riguardato lo svolgimento della analisi del rischio volto ad individuare possibili fallimenti nelle procedure adottate per il trattamento del paziente sottoposto a cicli di prot…

Settore ING-IND/20 - Misure E Strumentazione Nucleariprotonterapia Analisi di sicurezza Hierarchical Task Analysis Cognitive Task Analysis Human Error Assessment and Reduction TechniqueSettore ING-IND/19 - Impianti Nucleari
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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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Simulated Annealing Technique for Fast Learning of SOM Networks

2011

The Self-Organizing Map (SOM) is a popular unsupervised neural network able to provide effective clustering and data visualization for multidimensional input datasets. In this paper, we present an application of the simulated annealing procedure to the SOM learning algorithm with the aim to obtain a fast learning and better performances in terms of quantization error. The proposed learning algorithm is called Fast Learning Self-Organized Map, and it does not affect the easiness of the basic learning algorithm of the standard SOM. The proposed learning algorithm also improves the quality of resulting maps by providing better clustering quality and topology preservation of input multi-dimensi…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniComputer Science::Machine LearningArtificial IntelligenceSOM Simulated annealing Clustering Fast learningArtificial neural networkWake-sleep algorithmbusiness.industryComputer scienceTopology (electrical circuits)computer.software_genreAdaptive simulated annealingGeneralization errorData visualizationComputingMethodologies_PATTERNRECOGNITIONArtificial IntelligenceSimulated annealingUnsupervised learningData miningbusinessCluster analysisSelf Organizing map simulated annealingcomputerSoftware
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