Search results for "LOAD"

showing 10 items of 1967 documents

Load Flow Solution of radial distribution networks with ZI loads

2008

In this paper, a methodology to solve radial distribution networks, with constant current and/or impedance loads, is proposed. The techniques currently available to solve such systems are based either on iterative methods or on the bus impedance matrix. The method developed is the extension of a technique that is valid to solve networks made of impedances with one supply point. The methodology can be applied to directly and rapidly solve large distribution systems in which the loads are modeled as constant current/impedance. It is also able to solve meshed systems having voltage-dependent loads, inside an iterative backward/forward method.

Settore ING-IND/33 - Sistemi Elettrici Per L'EnergiaLoad FlowRadial distribution networks
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A HEURISTIC LOAD MANAGEMENT APPROACH FOR DOMESTIC APPLIANCES

2014

In this paper, an innovative heuristic for domestic loads management is proposed. The method is straightforward and easy to be implemented on embedded systems. The idea is to start from the mathematical modeling of loads and to perform a profile based scheduling, namely loads will try to fit a given schedule. The solution of the scheduling is based on a rolling horizon of 24 hours and is recomputed when an ON signal is provided to the considered appliance. Experimental results show the pertinence of the approach and how it may be profitably used to lower the energy costs for the end user.

Settore ING-IND/33 - Sistemi Elettrici Per L'EnergiaLoad shifting Smart grid Domestic loads optimization
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A Multi-Port Approach to Solve Distribution Networks with Meshes and PV Nodes

2007

A new methodology based on the backward/forward (b/f) technique for the load flow solution in distribution systems is here proposed. The methodology takes efficiently into account the fixed voltage nodes and uses a reduced bus impedance matrix. In this way, it is possible to attain, for the unknowns at the PV nodes, the same values that are attainable solving the network with the methods adopted for transmission systems. With the same methodology it is possible to take into account also the meshes. If the network contains only meshes, the relevant model is linear and it is the one including the compensation currents. The presence of PV nodes introduces non linearity in the model and an iter…

Settore ING-IND/33 - Sistemi Elettrici Per L'EnergiaMathematical optimizationRobustness (computer science)Computer scienceIterative methodConvergence (routing)LinearityPolygon meshBackward/forward method load flow distribution networks PV nodes.Power-flow studyTransmission systemVoltage2007 IEEE Lausanne Power Tech
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Experimental Set up of Advanced Lighting Systems for Load Shifting Strategies

2021

Shiftable and modulable loads are an essential part of smart grids in the effort for improving the efficiency of the power system and providing new ancillary services. Most of the researches considered shiftable loads and the impact on the power grid. Smart lighting systems are able to modulate their consumption while preserving the visual duty, therefore they can take part to this action. In this context, this paper presents an advanced experimental setup implemented in the SolarLab of the University of Palermo, with the aim of studying the impact on the end-user's energy consumption and on the power grid of smart lighting systems. In this light, different control strategies will be consid…

Settore ING-IND/33 - Sistemi Elettrici Per L'Energiashiftable loadBuilding Automationsmart lightingDaylight-Linked control systemCCT2021 IEEE International Conference on Environment and Electrical Engineering and 2021 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe)
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A SURVEY ON SMART GRIDS ACTIONS AND COMPONENTS FOR ENERGY CONSUMPTIONS OPTIMIZATION

2014

In the paper a survey on the features that a smart grid has to perform for energy consumptions optimization are presented and explained. By optimizing the loads usage with the grid priorities both end-users and the energy providers can save energy (and so CO2 emissions) and money. In the paper the conceive of an architecture in-home and at residential level is proposed to arrange a smart grid with its intelligent and connected load consumers. Qualitative results from the European research project “BeyWatch” are here mentioned in order to explain how the conceived main services in smart grid, like monitoring and control services, energy management services and load management services allow …

Settore ING-IND/33 - Sistemi Elettrici Per L'Energiasmart grid load management energy consumption optimization monitoring and controlSettore ING-IND/32 - Convertitori Macchine E Azionamenti Elettrici
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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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Offloading through Opportunistic Networks with Dynamic Content Requests

2014

Offloading is gaining momentum as a technique to overcome the cellular capacity crunch due to the surge of mobile data traffic demand. Multiple offloading techniques are currently under investigation, from modifications inside the cellular network architecture, to integration of multiple wireless broadband infrastructures, to exploiting direct communications between mobile devices. In this paper we focus on the latter type of offloading, and specifically on offloading through opportunistic networks. As opposed to most of the literature looking at this type of offloading, in this paper we consider the case where requests for content are non-synchronised, i.e. users request content at random …

Settore ING-INF/03 - TelecomunicazioniOpportunistic network Mobile Data Offloading Dynamic Contet Request WiFi-direct BluetoothOpportunistic Networks
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A Hybrid Framework for Soft Real-Time WSN Simulation

2009

The design of a wireless sensor network is a chal- lenging task due to its intrinsically application-specific nature. Although a typical choice for testing such kind of networks requires devising ad-hoc testbeds, this is often impractical as it depends on expensive, and hard to maintain deployment of nodes. On the other hand, simulation is a valuable option, as long as the actual functioning conditions are reliably modeled, and carefully replicated. The present work describes a framework for supporting the user in early design and testing of a wireless sensor network with an augmented version of TOSSIM, the de-facto standard for simulators, that allows merging actual and virtual nodes seaml…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniComputer scienceDistributed computingLoad modelingReal-time computingData modelingTask (computing)Key distribution in wireless sensor networksTelecommunication computingSoftware deploymentCode (cryptography)Soft-real timeWireless sensor networkWireless Sensor NetworkSimulation
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An Evaluation of HCI and CMC in Information Systems within Highly Crowded Large Events

2013

Pervasive systems are composed of a large variety of networked smart devices that supposedly enrich the environment they are deployed in. The access to services provided by a pervasive system should be as natural and “unconscious” as possible. In a large number of cases, the available interaction modality seems to be more oriented towards showing off technological wonders rather than to the actual usability of the interface. In this paper we evaluate and compare two different versions of an information provision system deployed in two editions of a large fair. In particular, we will focus on the Human-Computer Interaction (HCI) and Computer-Mediated-Communication (CMC) points of view. The a…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniInteractive systems engineeringUbiquitous computingbusiness.industryComputer sciencecognitive loadlarge eventsUsabilityComputer Mediated Communication (CMC)Human-centered computingHuman Computer Interaction (HCI)Social dynamicsHuman–computer interactionInformation systemComputer-mediated communicationbusinessCognitive ergonomics2013 Seventh International Conference on Complex, Intelligent, and Software Intensive Systems
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Composite laminates buckling optimization through Levy based Ant Colony Optimization

2010

In this paper, the authors propose the use of the Levy probability distribution as leading mechanism for solutions differentiation in an efficient and bio-inspired optimization algorithm, ant colony optimization in continuous domains, ACOR. In the classical ACOR, new solutions are constructed starting from one solution, selected from an archive, where Gaussian distribution is used for parameter diversification. In the proposed approach, the Levy probability distributions are properly introduced in the solution construction step, in order to couple the ACOR algorithm with the exploration properties of the Levy distribution. The proposed approach has been tested on mathematical test functions…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniMathematical optimizationComputer scienceGaussianAnt colony optimization algorithmsLévy distributionMaximizationFunction (mathematics)Composite laminatessymbols.namesakeDistribution (mathematics)symbolsProbability distributionSettore ICAR/08 - Scienza Delle CostruzioniLevy probability distribution Ant colony optimization composite laminates buckling load maximization
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