Search results for "Computer Networks"

showing 10 items of 860 documents

Enforcing mobile security with location-aware role-based access control

2013

This paper describes how location-aware role-based access control RBAC can be implemented on top of the Geospatial eXtensible Access Control Markup Language GeoXACML. It furthermore sketches how spatial separation of duty constraints both static and dynamic can be implemented using GeoXACML on top of the XACML RBAC profile. The solution uses physical addressing of geographical locations, which facilitates easy deployment of authorisation profiles to the mobile device. Location-aware RBAC can be used to implement location-dependent access control and also other security enhancing solutions on mobile devices, such as location-dependent device locking, firewall, intrusion prevention or payment…

Markup languageGeospatial analysisComputer Networks and CommunicationsComputer scienceSeparation of dutiesbusiness.industryXACML020206 networking & telecommunicationsAccess control02 engineering and technologyComputer securitycomputer.software_genreFirewall (construction)020204 information systems0202 electrical engineering electronic engineering information engineeringRole-based access controlbusinessMobile devicecomputerInformation Systemscomputer.programming_languageComputer networkSecurity and Communication Networks
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Progress in Violet Light-Emitting Diodes Based on ZnO/GaN Heterojunction

2020

Progress in light-emitting diodes (LEDs) based on ZnO/GaN heterojunctions has run into several obstacles during the last twenty years. While both the energy bandgap and lattice parameter of the two semiconductors are favorable to the development of such devices, other features related to the electrical and structural properties of the GaN layer prevent an efficient radiative recombination. This work illustrates some advances made on ZnO/GaN-based LEDs, by using high-thickness GaN layers for the p-region of the device and an ad hoc device topology. Heterojunction LEDs consist of a quasicoalesced non-intentionally doped ZnO nanorod layer deposited by chemical bath deposition onto a metal&ndash

Materials scienceComputer Networks and CommunicationsBand gapgrowthlcsh:TK7800-836002 engineering and technologyfabricationElectroluminescence01 natural sciencesSettore ING-INF/01 - Elettronicaganlaw.inventionelectroluminescencelawleds0103 physical sciencesmorphologyzno/gan heterojunction ledsSpontaneous emissionElectrical and Electronic Engineeringepitaxial p-gan layers010302 applied physicsZnO nanorodbusiness.industryzno nanorodszno/gan heterostructurelcsh:Electronicsepitaxial p-GaN layerHeterojunctiondependence021001 nanoscience & nanotechnologyoptical-propertieschemical bath depositionSemiconductorHardware and ArchitectureControl and Systems EngineeringZnO/GaN heterojunction LEDSignal ProcessingznoOptoelectronicsNanorod0210 nano-technologybusinessnanorodsChemical bath depositionLight-emitting diode
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RFID epidermal sensor including hydrogel membranes for wound monitoring and healing

2015

This contribution experimentally demonstrates for the first time the feasibility of joint application of passive UHF RFID technology and hydrogel membranes to fabricate smart plasters able to gather and remotely transmit information on the conditions of human skin. In particular, this intelligent plaster is sensitive to temperature and fluid uptake/release and could open interesting scenarios in wound healing monitoring and drug delivery.

Materials scienceComputer Networks and CommunicationsRFID sensortechnology industry and agriculturesmart plasterSettore ING-INF/02 - Campi ElettromagneticiWound monitoringepidermal electronics; hydrogel; RFID sensor; smart plaster; would healing;epidermal electronicDrug deliveryHydrogel membraneepidermal electronicsElectrical and Electronic Engineeringhydrogelwould healingBiomedical engineering
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Performance Study of Split Ferrite Cores Designed for EMI Suppression on Cables

2020

The ideal procedure to start designing an electronic device is to consider the electromagnetic compatibility (EMC) from the beginning. Even so, EMC problems can appear afterward, especially when the designed system is interconnected with external devices. Thereby, electromagnetic interferences (EMIs) could be transmitted to our device from power cables that interconnect it with an external power source or are connected to another system to establish wired communication. The application of an EMI suppressor such as a sleeve core that encircles the cables is a widely used technique to attenuate EM disturbances. This contribution is focused on the characterization of a variation of this cable …

Materials scienceComputer Networks and Communicationsgaplcsh:TK7800-8360Mechanical engineeringsplit-core02 engineering and technologynanocrystalline (NC)01 natural sciencescable filteringEMI0103 physical sciences0202 electrical engineering electronic engineering information engineeringElectrical and Electronic EngineeringWired communicationElectrical impedance010302 applied physicsInterconnectionEnginyeria elèctricalcsh:ElectronicsElectromagnetic compatibilityrelative permeabilityelectromagnetic interference (EMI) suppressors020206 networking & telecommunicationsFerrite coreFinite element methodPower (physics)snap ferritesleeve ferrite coresHardware and ArchitectureControl and Systems EngineeringimpedanceSignal ProcessingDC currents
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Performance Enhancement of Alkaline Water Electrolyzer Using Nanostructured Electrodes Synthetized by Template Electrosynthesis

2018

The increase of power generation by renewable sources is causing problems in the management of the electricity grid. In order to favor the transition from the current energy production towards renewable energy sources, it is necessary to plan strategy to develop suitable energy storage systems. Certainly, the electrochemical hydrogen production can be considered as one of the most promising storage technologies. In this work, an innovative alkaline electrolyzer is presented from its design based on the use of nanostructured electrodes up to its implementation suggested by the results of tests simulating real operation. The nanostructured electrodes were fabricated by template electrosynthes…

Materials scienceEnergy storagehydrogen productionnanowires nichel cobalt alloy 3D printed cell water splitting hydrogen alkaline electrolysiEnergy Engineering and Power TechnologyNanotechnologyElectrochemistryElectrosynthesisEnergy storageIndustrial and Manufacturing Engineeringlaw.inventionlawArtificial IntelligenceInstrumentationHydrogen productionElectrolysisbusiness.industryRenewable Energy Sustainability and the Environmentnanostructured materialAlkaline water electrolysisComputer Science Applications1707 Computer Vision and Pattern RecognitionRenewable energyElectricity generationComputer Networks and CommunicationSettore ING-IND/23 - Chimica Fisica Applicatabusiness
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Fabrication and Characterisation of Perovskite Thin Films for Photovoltaic Application

2018

This paper presents an alternative way to obtain perovskite thin films for photovoltaic application. This technique results more competitive, scalable, low-cost, reproducible and is different from other most common methods of fabrication.

Materials scienceFabricationthin filmRenewable Energy Sustainability and the EnvironmentPhotovoltaic systemPerovskite solar cellEnergy Engineering and Power TechnologyNanotechnologyComputer Science Applications1707 Computer Vision and Pattern RecognitionPerovskite solar cellIndustrial and Manufacturing EngineeringComputer Networks and CommunicationSettore ING-IND/23 - Chimica Fisica ApplicataArtificial Intelligenceperovskite thin films electrodeposition lead oxide solar cellThin filmInstrumentationPerovskite (structure)electrochemical deposition
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Photonic processing of microwave signals

2005

In this paper, recent advances in the implementation of photonic tuneable transversal filters for RF signal processing developed by the Optical Communications Group are described. After a brief introduction to the field and the basic concepts, limiting factors and application of these filters are described in the field. This is based on a distinction between filters based on wavelength tuneable optical taps and others based on the tuneability of the dispersive elements that provide the time delay between samples. Recently developed approaches have also been discussed.

Materials scienceField (physics)Computer Networks and Communicationsbusiness.industryMicrowave signalsOptical communicationLimitingÒpticaAtomic and Molecular Physics and OpticsWavelengthElectronic engineeringRadio frequencyElectrical and Electronic EngineeringPhotonicsbusinessComputer Science::Databases
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Donor/Acceptor Heterojunction Organic Solar Cells

2020

The operation and the design of organic solar cells with donor/acceptor heterojunction structure and exciton blocking layer is outlined and results of their initial development and assessment are reported. Under halogen lamp illumination with 100 mW/cm2 incident optical power density, the devices exhibits an open circuit voltage VOC = 0.45 V, a short circuit current density JSC between 2 and 2.5 mA/cm2 with a fill factor FF &asymp

Materials scienceOrganic solar cellComputer Networks and Communicationslcsh:TK7800-836002 engineering and technology010402 general chemistrySettore ING-INF/01 - Elettronica01 natural scienceslaw.inventionorganic photovoltaicexciton blocking layerdonor/acceptor heterojuntionlawElectrical and Electronic Engineeringbusiness.industryOpen-circuit voltagelcsh:ElectronicsEnergy conversion efficiencyorganic solar cellsHeterojunction021001 nanoscience & nanotechnologyAcceptor0104 chemical sciencesHalogen lampHardware and ArchitectureControl and Systems EngineeringOrganic solar celllifetime and degradationSignal ProcessingOptoelectronicsQuantum efficiencyorganic photovoltaics0210 nano-technologybusinessShort circuitElectronics
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Partial Discharges Diagnostics Along Medium Voltage Cables

2018

In the last years different partial discharge (PD) measuring techniques have been developed because PD diagnostic is the most widely tool to evaluate the insulation condition of a power cable. Recently non-conventional methods and sensors have been used in order to reach improved results in PD measurements. New sensors based on wireless technology were developed in order to simplify PD measurement especially for on-line, on-site diagnosis. The purpose of this work is to perform measurements that allow to study the variation of pulses when they travel along a medium voltage cable and characterize a new smart PD source detector and locator, named Wings sensor. For these purposes, internal PD …

Materials scienceRenewable Energy Sustainability and the Environmentbusiness.industryAcousticsPD MeasurementDetectordiagnosticEnergy Engineering and Power TechnologyComputer Science Applications1707 Computer Vision and Pattern RecognitionRotationSignalIndustrial and Manufacturing Engineeringantenna sensorpartial dischargeSettore ING-IND/31 - ElettrotecnicaComputer Networks and CommunicationIntelligent sensorArtificial IntelligencePartial dischargeWirelessPower cablebusinessInstrumentationVoltage2018 IEEE 4th International Forum on Research and Technology for Society and Industry (RTSI)
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Experimental Characterization of the Human Meniscal Tissue

2018

The meniscus plays a critical role in load transmission, stability and energy dissipation in the knee joint. Loss of the meniscus leads to joint degeneration and osteoarthritis. In a number of cases replacement of the resected meniscal tissue by a synthetic implant might avoid the articular cartilage degeneration. None of the available implants presents optimal biomechanics characteristic due to the fact the biomechanics functionality of the meniscus is not yet fully understood. Mimicking the native biomechanical characteristics of the menisci seems to be the key factor in meniscus replacement functioning. This is extremely challenging due to its complex inhomogeneous microstructure, the la…

Materials sciencemeniscal tissue0206 medical engineeringEnergy Engineering and Power TechnologyArticular cartilage02 engineering and technologyDegeneration (medical)OsteoarthritisKnee JointMeniscus (anatomy)fractional viscoelasticityIndustrial and Manufacturing Engineering0203 mechanical engineeringArtificial IntelligencemedicineInstrumentationMeniscal tissueRenewable Energy Sustainability and the EnvironmentBiomechanicsComputer Science Applications1707 Computer Vision and Pattern Recognitionmusculoskeletal systemmedicine.disease020601 biomedical engineeringCharacterization (materials science)Computer Networks and Communication020303 mechanical engineering & transportsmedicine.anatomical_structureBiaxial testSettore ICAR/08 - Scienza Delle CostruzioniBiomedical engineering2018 IEEE 4th International Forum on Research and Technology for Society and Industry (RTSI)
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