Search results for "Arrow"

showing 10 items of 953 documents

Quantification and automatized adaptive detection of in vivo and in vitro neuronal bursts based on signal complexity.

2015

In this paper, we propose employing entropy values to quantify action potential bursts in electrophysiological measurements from the brain and neuronal cultures. Conventionally in the electrophysiological signal analysis, bursts are quantified by means of conventional measures such as their durations, and number of spikes in bursts. Here our main aim is to device metrics for burst quantification to provide for enhanced burst characterization. Entropy is a widely employed measure to quantify regularity/complexity of time series. Specifically, we investigate the applicability and differences of spectral entropy and sample entropy in the quantification of bursts in in vivo rat hippocampal meas…

Computer scienceQuantitative Biology::Tissues and OrgansAstrophysics::High Energy Astrophysical PhenomenaEntropyCell Culture TechniquesElectrophysiological PhenomenaAction Potentialsta3112HippocampusEntropy (classical thermodynamics)In vivoEntropy (information theory)AnimalsEntropy (energy dispersal)Rats WistarEntropy (arrow of time)ta217NeuronsSignal processingQuantitative Biology::Neurons and Cognitionta213Entropy (statistical thermodynamics)Signal Processing Computer-Assistedadaptive detectionelectrophysiological signal analysisquantificationneuronal burstsElectrophysiological PhenomenaSample entropyElectrophysiologyElectrophysiologyMicroelectrodeBiological systemNeuroscienceMicroelectrodesEntropy (order and disorder)Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
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Modeling, analysis, and simulation of MIMO mobile-to-mobile fading channels

2008

This paper' deals with the modeling, analysis, and simulation of multiple-input multiple-output (MIMO) narrowband fading channels for mobile-to-mobile communications. A stochastic MIMO mobile-to-mobile reference channel model is derived from the geometrical two-ring scattering model under the assumption that both the transmitter and the receiver are surrounded by an infinite number of local scatterers. Using a wave propagation model, the complex channel gains are derived and their statistical properties are studied. General analytical solutions are provided for the three-dimensional (3-D) space-time cross-correlation function (CCF). We show that this function can be expressed as the product…

Computer scienceScatteringEstimation theorybusiness.industryApplied MathematicsMIMOTransmitterTopologyComputer Science ApplicationsNarrowbandAngle of arrivalFadingElectrical and Electronic EngineeringTelecommunicationsbusinessComputer Science::Information TheoryCommunication channelIEEE Transactions on Wireless Communications
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ErrorSense: Characterizing WiFi Error Patterns for Detecting ZigBee Interference

2014

Recent years have witnessed the increasing adoption of heterogeneous wireless networks working in unlicensed ISM bands, thus creating serious problems of spectrum overcrowding. Although ZigBee, Bluetooth and WiFi networks have been natively designed for working in presence of interference, it has been observed that several performance impairments may occur because of heterogeneous sensitivity to detect or react to the presence of other technologies. In this paper we focus on the WiFi capability to detect interfering ZigBee links. Despite of the narrowband transmissions performed by ZigBee, in emerging scenarios ZigBee interference can have a significant impact on WiFi performance. Therefore…

Computer scienceWireless networkbusiness.industrySettore ING-INF/03 - TelecomunicazioniComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSwlan 802.11 802.15.4 frame error detection wireless coexistenceInterference (wave propagation)law.inventionBluetoothNarrowbandlawSensitivity (control systems)businessHeterogeneous networkComputer networkNeuRFon
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Performance evaluation of sum-of-cisoids Rice/Rayleigh fading channel simulators with respect to the bit error probability

2014

Sum-of-cisoids (SOC) processes provide an important framework for the modeling and simulation of multipath fading channels. In this paper, we analyze the performance of SOC Rice/Rayleigh narrowband fading channel simulators with respect to the bit error probability (BEP) of quadrature phase shift keying (QPSK) and differential phase shift keying (DPSK) systems with both coherent and noncoherent demodulation. For the BEP of coherent QPSK and DPSK, exact analytical expressions are derived, which provide insight into the influence of the number of propagation paths and the path gains on the system performance. It will be shown that at least 10 multipath components are required to guarantee tha…

Computer sciencebusiness.industryKeyingCondensed Matter PhysicsComputer Science::PerformanceNarrowbandGeneral Earth and Planetary SciencesDemodulationFadingElectrical and Electronic EngineeringTelecommunicationsbusinessAlgorithmMultipath propagationComputer Science::Information TheoryCommunication channelPhase-shift keyingRayleigh fadingRadio Science
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Advanced imaging of the gastrointestinal tract: research vs. clinical tools?

2009

Diagnostic endoscopy has moved forward considerably in the recent years. Still, three major needs have to be satisfied: endoscopy should be able to detect a lesion, characterize the lesion, and then its nature should be confirmed. These steps should ideally translate into an immediate therapeutic decision.High definition endoscopy has optimized our endoscopic view onto the mucosa and can be combined with digital surface enhancement modalities. Chromoendoscopy still holds a place to detect especially flat lesions in high-risk patients such as ulcerative colitis. Digital chromoendoscopy techniques such as narrow band imaging, i-scan, or Fuji intelligent chromo endoscopy offer new possibilitie…

Confocal laser endomicroscopymedicine.medical_specialtyGastrointestinal tractBiomedical ResearchNarrow-band imagingmedicine.diagnostic_testbusiness.industryHigh definition endoscopyGastroenterologyChromoendoscopyEndoscopyDiagnosis DifferentialLesionAutofluorescencemedicineHumansEndoscopy Digestive SystemRadiologymedicine.symptombusinessGastrointestinal NeoplasmsCurrent Opinion in Gastroenterology
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Conservation genetics of an endemic from the Mediterranean Basin: high genetic differentiation but no genetic diversity loss from the last population…

2013

The Mediterranean Basin is a biodiversity hotspot, housing > 11.000 narrowly endemic plant species, many of which are declining due to mass tourism and agricultural intensification. To investigate the genetic resource impacts of ongoing habitat loss and degradation, we characterized the genetic variation in the last known populations of Leopoldia gussonei, a self-compatible endangered Sicilian Grape Hyacinth numbering less than 3,000 remaining individuals, using AFLP. Results demonstrated significant genome-wide genetic differentiation among all extant populations (I broken vertical bar(ST) = 0.05-0.56), and genetic clustering according to geographic location. Gene diversity was fairly c…

Conservation geneticsGenetic diversityeducation.field_of_studyAFLPHabitat fragmentationEcologyPopulation sizeHabitat degradationPopulationBiodiversityHabitat lossBiologyAFLP; Asparagaceae; Habitat degradation; Habitat loss; Mediterranean Basin; Narrow endemicsGenetic driftGenetic variationGeneticsMediterranean BasinNarrow endemicseducationEcology Evolution Behavior and SystematicsAsparagaceaeConservation Genetics
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Exact controllability to trajectories for entropy solutions to scalar conservation laws in several space dimensions

2019

We describe a new method which allows us to obtain a result of exact controllability to trajectories of multidimensional conservation laws in the context of entropy solutions and under a mere non-degeneracy assumption on the flux and a natural geometric condition.

Conservation law010102 general mathematicsGeneral Medicine01 natural sciencesControllabilityMathematics - Analysis of PDEsOptimization and Control (math.OC)0103 physical sciencesFOS: MathematicsApplied mathematics[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]010307 mathematical physics[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC]0101 mathematicsEntropy (arrow of time)Mathematics - Optimization and ControlMathematicsAnalysis of PDEs (math.AP)
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A New Coupling Solution for G3-PLC Employment in MV Smart Grids

2019

This paper proposes a new coupling solution for transmitting narrowband multicarrier power line communication (PLC) signals over medium voltage (MV) power lines. The proposed system is based on an innovative PLC coupling principle, patented by the authors, which exploits the capacitive divider embedded in voltage detecting systems (VDS) already installed inside the MV switchboard. Thus, no dedicated couplers have to be installed and no switchboard modifications or energy interruptions are needed. This allows a significant cost reduction of MV PLC implementation. A first prototype of the proposed coupling system was presented in previous papers: it had a 15 kHz bandwidth useful to couple sin…

Control and Optimizationpower system measurementComputer scienceOrthogonal frequency-division multiplexingEnergy Engineering and Power Technologylcsh:Technologypower system communicationNarrowbandsmart gridsElectrical and Electronic EngineeringCenter frequencysmart gridEngineering (miscellaneous)Renewable Energy Sustainability and the Environmentbusiness.industrylcsh:TBandwidth (signal processing)Electrical engineeringpower system measurementsnarrow band power line communicationPower-line communicationElectric power transmissionSmart gridModulationcommunication system performanceICT infrastructure for smart gridbusinessSettore ING-INF/07 - Misure Elettriche E ElettronicheEnergy (miscellaneous)VoltageEnergies
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High-order modes in cavity-resonator-integrated guided-mode resonance filters (CRIGFs)

2015

International audience; Cavity-resonator-integrated guided-mode resonance filters (CRIGFs) are optical filters based on weak coupling by a grating between a free-space propagating optical mode and a guided mode, like guided-mode resonance filters (GMRFs). As compared to GMRFs they offer narrowband reflection with small aperture and high angular acceptance. We report experimental characterization and theoretical modeling of unexpected high-order reflected modes in such devices. Using coupled-mode modeling and moiré analysis we provide physical insight on key mechanisms ruling CRIGF properties. This model could serve as a simple and efficient framework to design new reflectors with tailored s…

CouplingPhysicsGuided-mode resonancebusiness.industryResonanceGratingCoupled mode theoryAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsResonatorNarrowbandOptics[SPI.OPTI]Engineering Sciences [physics]/Optics / PhotonicComputer Vision and Pattern Recognition[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/MicroelectronicsOptical filterbusiness
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"Table 3" of "Search for pairs of highly collimated photon-jets in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector"

2018

The observed upper limits on the production cross-section times the product of branching ratios for the benchmark signal scenario involving a scalar particle $X$ with narrow width decaying via $X\rightarrow aa\rightarrow 4\gamma$, $\sigma_X\times B(X\rightarrow aa)\times B(a\rightarrow\gamma\gamma)^2$. The limits for $m_{a}$ = 5 GeV and 10 GeV do not cover as large a range as the other mass points, since the region of interest is limited to $ m_{a} < 0.01 \times m_{X}$.

Cross-section$pp\rightarrow X \rightarrow aa \rightarrow 4\gamma$Observed limit13000Photon-jet
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