Search results for "Codes"

showing 10 items of 201 documents

On the influence of the physico-chemical properties of aerosols on the life cycle of radiation fogs

1991

A one-dimensional model of radiation fog with detailed microphysics is presented. Aerosols and cloud droplets are treated in a joint two-dimensional size distribution. Radiative fluxes are calculated as functions of the radiative properties of the time-dependent particle spectra. The droplet growth equation is solved by considering radiative effects. Turbulence is treated by means of a higher order closure model. The interaction between the atmosphere and the earth's surface is explicitly simulated. Three numerical sensitivity studies are performed to investigate the impact of the different physico-chemical properties of urban, rural and maritime aerosols on fog formation. Numerical results…

Fluid Flow and Transfer ProcessesAtmospheric ScienceEnvironmental EngineeringMaterials scienceMeteorologyMicrophysicsTurbulencePlanetary boundary layerMechanical EngineeringMechanicsRadiationAtmospheric sciencesPollutionAerosolAtmosphereFogAtmospheric radiative transfer codesLiquid water contentRadiative transferEnvironmental scienceParticlePhysics::Atmospheric and Oceanic PhysicsBoundary-Layer Meteorology
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Exploring the spatial relationship between airborne-derived red and far-red sun-induced fluorescence and process-based GPP estimates in a forest ecos…

2019

International audience; Terrestrial gross primary productivity (GPP) plays an essential role in the global carbon cycle, but the quantification of the spatial and temporal variations in photosynthesis is still largely uncertain. Our work aimed to investigate the potential of remote sensing to provide new insights into plant photosynthesis at a fine spatial resolution. This goal was achieved by exploiting high-resolution images acquired with the FLuorescence EXplorer (FLEX) airborne demonstrator HyPlant. The sensor was flown over a mixed forest, and the images collected were elaborated to obtain two independent indicators of plant photosynthesis. First, maps of sun-induced chlorophyll fluore…

Forest ecosystems[SDV.SA]Life Sciences [q-bio]/Agricultural sciences010504 meteorology & atmospheric sciencesFIS/06 - FISICA PER IL SISTEMA TERRA E PER IL MEZZO CIRCUMTERRESTRE0208 environmental biotechnologyGEO/04 - GEOGRAFIA FISICA E GEOMORFOLOGIASpectral fitting methodSoil Science02 engineering and technology01 natural sciencesArticleCarbon cycleGEO/11 - GEOFISICA APPLICATAAtmospheric radiative transfer codesAirborne spectroscopyForest ecologySun-induced chlorophyll fluorescenceddc:550LUEEcosystemAPARSun-induced chlorophyll fluorescenceSpectral fitting methodPlant traitsINFORMGPPAPARLUEBESSForest ecosystemsHyPlantAirborne spectroscopyComputers in Earth SciencesChlorophyll fluorescenceBESS0105 earth and related environmental sciencesRemote sensingPlant traitsINFORMGEO/12 - OCEANOGRAFIA E FISICA DELL'ATMOSFERAGeology15. Life on land020801 environmental engineeringSpatial heterogeneityGEO/10 - GEOFISICA DELLA TERRA SOLIDA13. Climate actionHyPlantEnvironmental scienceSpatial variabilityGPPScale (map)
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Detection of Signals in MC–CDMA Using a Novel Iterative Block Decision Feedback Equalizer

2022

This paper presents a technique to mitigate multiple access interference (MAI) in multicarrier code division multiple access (MC-CDMA) wireless communications systems. Although under normal circumstances the MC-CDMA system can achieve high spectral efficiency and resistance towards inter symbol interference (ISI) however when exposed to substantial nonlinear distortion the issue of MAI manifests. Such distortion results when the power amplifiers are driven into saturation or when the transmit signal experiences extreme adverse channel conditions. The proposed technique uses a modified iterative block decision feedback equalizer (IB-DFE) that uses a minimal mean square error (MMSE) receiver …

General Computer ScienceIterative methodsMultiaccess communicationReceiversMMSENonlinear distortionCodesFeedbackCDMA[SPI]Engineering Sciences [physics]CDMA OFDM MAI MMSE IB-DFE Maximum Likelihood (ML)General Materials ScienceSpectral efficiencyMaximum likelihood (Ml)Electrical and Electronic EngineeringOFDMDecision feedback equalizers[PHYS]Physics [physics]TelecomunicacionesPower amplifiersGeneral EngineeringMAIMaximum Likelihood (ML)Multicarrier code division multiple accessAI and TechnologiesBit error rateIB-DFESignal detectionEngineering Research GroupIEEE Access
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Estimation of leaf area index using PROSAIL based LUT inversion, MLRA-GPR and empirical models: Case study of tropical deciduous forest plantation, N…

2020

Abstract Forests play a vital role in biological cycles and environmental regulation. To understand the key processes of forest canopies (e.g., photosynthesis, respiration and transpiration), reliable and accurate information on spatial variability of Leaf Area Index (LAI), and its seasonal dynamics is essential. In the present study, we assessed the performance of biophysical parameter (LAI) retrieval methods viz. Look-Up Table (LUT)-inversion, MLRA-GPR (Machine Learning Regression Algorithm- Gaussian Processes Regression) and empirical models, for estimating the LAI of tropical deciduous plantation using ARTMO (Automated Radiative Transfer Models Operator) tool and Sentinel-2 satellite im…

Global and Planetary Change010504 meteorology & atmospheric sciences0211 other engineering and technologiesEmpirical modellingRegression analysis02 engineering and technology15. Life on landManagement Monitoring Policy and LawAtmospheric sciences01 natural sciencesRegressionAtmospheric radiative transfer codesDeciduousSpatial variabilityComputers in Earth SciencesLeaf area index021101 geological & geomatics engineering0105 earth and related environmental sciencesEarth-Surface ProcessesMathematicsTranspirationInternational Journal of Applied Earth Observation and Geoinformation
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Estimating the phenological dynamics of irrigated rice leaf area index using the combination of PROSAIL and Gaussian Process Regression

2021

The growth of rice is a sequence of three different phenological phases. This sequence of change in rice phenology implies that the condition of the plant during the vegetative phase relates directly to the health of leaves functioning during the reproductive and ripening phases. As such, accurate monitoring is important towards understanding rice growth dynamics. Leaf Area Index (LAI) is an important indicator of rice yields and the availability of this information during key phenological phases can support more informed farming decisions. Satellite remote sensing has been adopted as a proxy to field measurements of LAI and with the launch of freely available high resolution Satellite imag…

Global and Planetary ChangePhenologyMultispectral imageManagement Monitoring Policy and LawAtmospheric radiative transfer codesKrigingGround-penetrating radarPaddy fieldSatelliteComputers in Earth SciencesLeaf area indexEarth-Surface ProcessesMathematicsRemote sensing
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Gray code for permutations with a fixed number of cycles

2007

AbstractWe give the first Gray code for the set of n-length permutations with a given number of cycles. In this code, each permutation is transformed into its successor by a product with a cycle of length three, which is optimal. If we represent each permutation by its transposition array then the obtained list still remains a Gray code and this allows us to construct a constant amortized time (CAT) algorithm for generating these codes. Also, Gray code and generating algorithm for n-length permutations with fixed number of left-to-right minima are discussed.

Golomb–Dickman constantPolynomial codeRestricted permutationsGenerating algorithms0102 computer and information sciences02 engineering and technology01 natural sciencesTheoretical Computer ScienceGray codeCombinatoricsPermutation[MATH.MATH-CO]Mathematics [math]/Combinatorics [math.CO]0202 electrical engineering electronic engineering information engineeringDiscrete Mathematics and CombinatoricsTransposition arrayComputingMilieux_MISCELLANEOUSMathematicsDiscrete mathematicsSelf-synchronizing codeAmortized analysisMathematics::CombinatoricsParity of a permutation020206 networking & telecommunicationsGray codes010201 computation theory & mathematicsConstant-weight codeMathematicsofComputing_DISCRETEMATHEMATICS
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Graphical THD minimization procedure for single phase five-level converters

2017

This paper proposes two graphycal procedure to mitigate h harmonics and to minimize the total harmonic distortion (THD), respectively. The paper considers a five-level inverter and fundamental frequency modulation: it computes the two switching angles able to reduce low order harmonics and able to minimize the THD. Simulation results are obtained and, in order to validate the proposed procedure, an experimental prototype is built and experimental results are carried out. The comparison between simulation and experimental results confirms the accuracy of the proposed graphycal procedure. It is shown that the switching angles to mitigate the third-fifth and the third-fifth-seventh harmonics e…

Graphycal Procedure; Grid Codes; Harmonics Mitigation; Multilevel Inverters; Total Harmonic Distortion (THD); Electrical and Electronic Engineering; Control and Systems EngineeringGraphycal ProcedureTotal harmonic distortionEngineeringbusiness.industryTotal Harmonic Distortion (THD)020208 electrical & electronic engineeringModulation indexGrid Codes02 engineering and technologyFundamental frequencyElectronic mailHarmonic analysisHarmonics MitigationMultilevel InvertersControl and Systems EngineeringControl theoryHarmonics0202 electrical engineering electronic engineering information engineeringHarmonicElectronic engineeringInverterElectrical and Electronic Engineeringbusiness2017 IEEE 26th International Symposium on Industrial Electronics (ISIE)
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Acanthocephalans from Marine Fishes from Patagonia, Argentina

2019

In this study, 542 individual fish from 20 species from the Patagonian continental shelf of Argentina were examined for acanthocephalans. A total of 1,547 acanthocephalans belonging to 5 species were collected from 18 species of fish. Adult forms were represented by 2 species: Aspersentis johni (Baylis, 1929) (Heteracanthocephalidae) from longtail southern cod, Patagonotothen ramsayi (Regan) (new host record), and Breizacanthus aznari Herna´ndez-Orts, Alama-Bermejo, Crespo, Garcı´a, Raga and Montero, 2012 (Arhythmacanthidae) from raneya, Raneya brasiliensis (Kaup). Immature worms of B. aznari were also collected from the intestine of pink cusk-eel, Genypterus blacodes (Forster) (new host re…

HeteracanthocephalidaebiologyParalichthysHost (biology)Otras Ciencias BiológicasZoologyGenypterus blacodesPolymorphidaebiology.organism_classificationACANTHOCEPHALACorynosoma bullosumCiencias BiológicasPolymorphidaePATAGONIAHeteracanthocephalidaeBreizacanthus aznariParasitologyCORYNOSOMAAcanthocephalaMesenteriesMARINE FISHESCIENCIAS NATURALES Y EXACTASEcology Evolution Behavior and SystematicsJournal of Parasitology
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Temperature and emissivity separation from calibrated data of the Digital Airborne Imaging Spectrometer

2001

Abstract The Digital Airborne Imaging Spectrometer (DAIS), with six thermal infrared channels in the 8–14 μm window, was flown over the Barrax test site, Spain, in the framework of the DAIS Experiment in the summer of 1998. Atmospheric correction of the DAIS thermal channels was performed by means of local radiosonde measurements and a radiative transfer model. Ground measurements of temperature and emissivity for six selected spots (two bare soils, two water bodies, and two vegetated fields) were conducted with the objective of providing calibration and validation targets. Three targets were used for a linear ground calibration of the DAIS thermal channels. With the ground-calibrated image…

Imaging spectrometerAtmospheric correctionSoil ScienceGeologyDaislaw.inventionAtmospheric radiative transfer codeslawThermalRadiosondeCalibrationEmissivityEnvironmental scienceComputers in Earth SciencesRemote sensingRemote Sensing of Environment
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Who turns to entrepreneurship later in life? - Push and pull in Finnish rural and urban areas

2014

Age is an important factor in entrepreneurship. The paths into entrepreneurship at a later age may be varied. Self-employment in later life may be either a form of partial retirement or a career option. Older individuals may also be pushed into self-employment. The focus of this paper is on the career choices of older individuals and their background motivations in Finland. The purpose is to analyse the factors and motives in terms of the push and pull dichotomy that lead individuals to enter self-employment at older ages in different types of labour markets in Finland, viz., rural and urban areas. Although some studies have focused on transitions to self-employment among older workers, que…

J14J26M13yrityksen perustaminen [self-employment; third age; rural and urban regions; habitual and novice entrepreneurship; necessity vs. opportunity JEL-codes]J24motiivitthird ageyrittäjyysnecessity vs. opportunityR23habitual and novice entrepreneurshipself-employmentjel:J24jel:J14older workersjel:J26ddc:330jel:M13jel:R23rural and urban regions
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