Search results for "Spectral"

showing 10 items of 3116 documents

Design and Simulation of Narrowband Indoor Radio Propagation Channels under LOS and NLOS Propagation Conditions

2010

Paper presented at the 2010 IEEE 71st Vehicular Technology Conference. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/VETECS.2010.5494116 This paper deals with the design and simulation of narrowband indoor propagation channels under line-of-sight (LOS) and non-LOS (NLOS) propagation conditions. We propose a reference cha…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Non-line-of-sight propagationNarrowbandComputer scienceAutocorrelationVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Electronic engineeringSpectral densityCommunication channel
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Modeling and Performance Analysis of Energy Efficiency Binary Power Control in MIMO-OFDM Wireless Communication Systems

2011

Published version of an article in the journal:International Journal of Distributed Sensor Networks. Also available from Hindawi Publishing: http://dx.doi.org/10.1155/2011/946258 The energy efficiency optimization of the binary power control scheme for MIMO-OFDM wireless communication systems is formulated, and then a global optimization solution of power allocation is derived. Furthermore, a new energy efficiency binary power control (EEBPC) algorithm is designed to improve the energy efficiency of MIMO-OFDM wireless communication systems. Simulation results show that the EEBPC algorithm has better energy efficiency and spectrum efficiency than the average power control algorithm in MIMO-O…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Scheme (programming language)Theoretical computer scienceArticle SubjectComputer Networks and CommunicationsComputer scienceBinary numberData_CODINGANDINFORMATIONTHEORY02 engineering and technologylcsh:QA75.5-76.950203 mechanical engineeringVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Computer Science::Networking and Internet Architecture0202 electrical engineering electronic engineering information engineeringElectronic engineeringGlobal optimizationComputer Science::Information Theorycomputer.programming_languageComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSGeneral Engineering020206 networking & telecommunications020302 automobile design & engineeringSpectral efficiencyMIMO-OFDMPower (physics)lcsh:Electronic computers. Computer sciencecomputerPower controlEfficient energy useInternational Journal of Distributed Sensor Networks
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Spectral adaptation of hyperspectral flight lines using VHR contextual information

2014

Abstract: Due to technological constraints, hyperspectral earth observation imagery are often a mosaic of overlapping flight lines collected in different passes over the area of interest. This causes variations in aqcuisition conditions such that the reflected spectrum can vary significantly between these flight lines. Partly, this problem is solved by atmospherical correction, but residual spectral differences often remain. A probabilistic domain adaptation framework based on graph matching using Hidden Markov Random Fields was recently proposed for transforming hyperspectral data from one image to better correspond to the other. This paper investigates the use of scale and angle invariant…

VHR imageryHyperspectral imaginggraph matchingComputer sciencebusiness.industrydomain adaptationPhysicsHyperspectral imagingPattern recognitionFilter (signal processing)Rendering (computer graphics)Computer Science::Computer Vision and Pattern RecognitionFull spectral imagingtextural featuresComputer visionArtificial intelligenceHidden Markov random fieldHidden Markov modelbusiness
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Simulation of the VUV spectral emission from the JT-60SA divertor

2021

A divertor survey dual-spectrometer is being designed by an EU-Japan team [1] to be installed on JT-60SA [2], the new fusion experiment expected to start operating in 2020. Positioned on an upper port, the primary role of the spectrometer is to analyse the radiation losses in the divertor region and to aid studying the physics of the divertor plasmas, including plasma detachment. Its spatial resolution capability is around 10 cm at the divertor and its two branches together cover the wavelength range from 10 to 130 nm, to satisfy the physics scope [3]. The spectrometer Lines Of Sight (LOS) are mapped onto a 2D SOLEDGE [4] simulations of the divertor region carried out for different density …

VUV spectrometerVUV spectral emissionJT-60SA divertorJT-60SA
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Specific UV and VUV spectra light sources

1997

The report contains information about laboratory made radiofrequency powered electrodeless discharge sources (lamps) of resonance atomic spectra radiation for various elements (e.g. Hg, Cd, Zn, O, S, Se, Te, As, Sb, Bi, J, Br, Kr, Xe, H) having main spectral lines in UV and VUV region. There are known, and can be found a lot of new specific applications of such sources in laboratory made or commercial optical devices.

Vacuum ultravioletChemistryKryptonAnalytical chemistryResonancechemistry.chemical_elementRadiationSpectroscopyUltraviolet radiationSpectral lineSPIE Proceedings
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X-ray absorption near edge spectroscopy at the Mn K-edge in highly homogeneous GaMnN diluted magnetic semiconductors

2006

We have studied by X-ray absorption spectroscopy the local environment of Mn in highly homogeneous Ga 1-x Mn x N (0.06 <x<0.14) thin epilayers grown by molecular beam epitaxy on [0001] SiC substrates. The measurements were performed in fluorescence mode around the Ga and Mn K-edges. In this report, we focus our attention to the X-ray absorption near edge spectroscopy (XANES) results. The comparison of the XANES spectra corresponding to the Ga and Mn edges indicates that Mn is substitutional to Ga in all samples studied. The XANES spectra measured at the Mn absorption edge shows in the near-edge region a double peak and a shoulder below the absorption edge and the main absorption peak after …

Valence (chemistry)Absorption edgeAbsorption spectroscopyK-edgeCondensed matter physicsChemistryAnalytical chemistryMagnetic semiconductorCondensed Matter PhysicsSpectroscopyXANESSpectral lineElectronic Optical and Magnetic Materialsphysica status solidi (b)
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Theoretical study of the electronic spectrum of p-benzoquinone

1999

The electronic excited states of p-benzoquinone have been studied using multiconfigurational second-order perturbation theory (CASPT2) and extended atomic natural orbital (ANO) basis sets. The calculation of the singlet–singlet and singlet–triplet transition energies comprises 19 valence singlet excited states, 4 valence triplet states, and the singlet 3s,3p, and 3d members of the Rydberg series converging to the first four ionization limits. The computed vertical excitation energies are found to be in agreement with the available experimental data. Conclusive assignments to both valence and Rydberg states have been performed. The main features of the electronic spectrum correspond to the π…

Valence (chemistry)ChemistryExcited statesGeneral Physics and AstronomyPerturbation theoryTriplet stateRydberg statesSpectral lineUNESCO::FÍSICA::Química físicaOrbital calculationssymbols.namesakeOrganic compounds Spectra ; Excited states ; Perturbation theory ; Triplet state ; Rydberg states ; Orbital calculationsOrganic compounds SpectraExcited stateIonizationRydberg formulasymbolsSinglet statePhysical and Theoretical ChemistryAtomic physicsTriplet state:FÍSICA::Química física [UNESCO]Excitation
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Valence electronic structure of C60: Theoretical analysis of photoemission data

1993

Abstract We present a theoretical investigation of the valence band photoemission spectra of C 60 using the nonempirical valence effective Hamiltonian (VEH) method. The VEH-DOVS curves calculated for the C 60 molecule are found to be in excellent agreement with synchrotron-radiation photoemission spectra reported for C 60 films. A detailed interpretation of all the photoemission bands is performed in the light of the VEH results.

Valence (chemistry)ChemistryMechanical EngineeringInverse photoemission spectroscopyMetals and AlloysAngle-resolved photoemission spectroscopyElectronic structureCondensed Matter PhysicsSpectral lineElectronic Optical and Magnetic MaterialsCondensed Matter::Materials Sciencesymbols.namesakeMechanics of MaterialsCondensed Matter::SuperconductivityMaterials ChemistrysymbolsValence bandMoleculeCondensed Matter::Strongly Correlated ElectronsAtomic physicsHamiltonian (quantum mechanics)Synthetic Metals
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A theoretical study of the electronic spectrum of bithiophene

1995

The electronic spectrum of bithiophene in the energy range up to 6.0 eV has been studied using multiconfigurational second order perturbation theory (CASPT2) and a basis set of ANO type, with split valence quality and including polarization functions on all heavy atoms. Calculations were performed at a planar (trans) and twisted geometry. The calculated ordering of the excited singlet states is 1Bu, 1Bu, 1Ag, 1Ag, and 1Bu with 0–0 transition energies: 3.88, 4.15, 4.40, 4.71, and 5.53 eV, respectively. The first Rydberg transition (3s) has been found at 5.27 eV. The results have been used in aiding the interpretation of the experimental spectra, and in cases where a direct comparison is poss…

Valence (chemistry)Electron spectraChemistryGeneral Physics and AstronomyGeometryExcited StatesSpectral lineUNESCO::FÍSICA::Química físicasymbols.namesakePlanarElectron SpectraThiopheneRydberg StatesExcited stateRydberg formulasymbolsPerturbation TheoryThiophene ; Electron Spectra ; Perturbation Theory ; Geometry ; Excited States ; Rydberg StatesPhysical and Theoretical ChemistryAtomic physics:FÍSICA::Química física [UNESCO]Excited singletBasis set
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Slow magnetic relaxation and water oxidation activity of dinuclear CoIICoIII and unique triangular CoIICoIICoIII mixed-valence complexes

2020

Construction of efficient multifunctional materials is one of the greatest challenges of our time. We herein report the magnetic and catalytic characterization of dinuclear [CoIIICoII(HL1)2(EtOH)(H2O)]Cl·2H2O (1) and trinuclear [CoIIICoII2(HL2)2(L2)Cl2]·3H2O (2) mixed valence complexes. Relevant structural features of the complexes have been mentioned to correlate with their magnetic and catalytic properties. Unique structural features, especially in terms of significant distortions around the CoII centre(s), prompted us to test both spin–orbit coupling (SOC) and zero field splitting (ZFS) methodologies for the systems. The positive sign of D values has been established from X-band EPR spec…

Valence (chemistry)Materials sciencechemistry.chemical_elementAtmospheric temperature rangeZero field splittingSpectral lineCatalysislaw.inventionInorganic ChemistryMagnetizationCrystallographychemistrylawElectron paramagnetic resonanceCobaltDalton Transactions
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