Search results for "Temporal"

showing 10 items of 1095 documents

Multi-spectral Reflection Photoplethysmography: Potential for Skin Microcirculation Assessment

2006

Technique for simultaneous recording of reflection photoplethysmography signals in broad spectral band (violet to NIR) has been developed, and its potential for assessment of blood microcirculation at various depths from the skin surface is discussed.

Materials scienceOpticsbusiness.industryTemporal resolutionPhotoplethysmogramSkin surfaceReflection (physics)Multi spectralSpectral bandsDiffuse reflectionequipment and suppliesbusinessMicrocirculationBiomedical Optics
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Scattering perspectives on nanostructural inhomogeneity in polymer network gels

2017

Abstract Scattering methods based on spatial and temporal contrast fluctuations in polymer-network gels, which originate from polymer-segmental density fluctuations, reveal rich insight into different types and levels of nanostructural inhomogeneity in these soft materials. Complementary contrasting as provided by light, neutron, and X-ray scattering allows such information to be obtained on nano- to micrometer length scales. On top of that, complementary use of static and dynamic scattering methods allows the interplay and effect of these inhomogeneities to be unraveled. This article interrelates a multitude of studies on the application of scattering techniques for analytical assessment o…

Materials sciencePolymers and PlasticsPolymer networkbusiness.industryScatteringOrganic ChemistryNanotechnology02 engineering and technologySurfaces and Interfaces010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesSoft materials0104 chemical sciencesMicrometreOpticsNano-Materials ChemistryCeramics and CompositesTemporal contrastNeutronBiological small-angle scattering0210 nano-technologybusinessProgress in Polymer Science
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Using the simplified falling head technique to detect temporal changes in field-saturated hydraulic conductivity at the surface of a sandy loam soil

2007

Abstract Determining temporal changes in field-saturated hydraulic conductivity ( K fs ) is important for understanding and modeling hydrological phenomena at the field scale. Little is known about temporal variability of K fs values measured at permanent sampling points. In this investigation, the simplified falling head (SFH) technique was used for an approximately 2-year period to determine temporal changes in K fs at 11 permanent sampling points established at the surface of a sandy loam soil. Additional K fs measurements were obtained by the single-ring pressure infiltrometer (PI) technique to also compare the SFH and PI techniques. The lowest mean values of K fs , M ( K fs ), were det…

Materials scienceRepeated samplingHydrostatic pressureAnalytical chemistrySoil ScienceMineralogyTemporal variabilitySaturated hydraulic conductivityHydraulic conductivityDry soilLoamMeasurement techniquesSoil waterSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliInfiltrometerAgronomy and Crop ScienceEarth-Surface Processes
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Dynamic control of the operation regimes of a mode-locked fiber laser based on intracavity polarizing fibers: experimental and theoretical validation.

2012

[EN] An intracavity polarizing fiber is proposed to control the emission regime of a passively mode-locked fiber laser. Stable operation in self-starting high and low dispersion soliton mode-locking and 100 GHz multiwavelength regimes is demonstrated through numerical simulations and experimental validation. Mode-locking stability is ensured by a saturable absorber in the ring cavity. The effective selection of operation regime is dynamically carried out by controlling the intracavity polarization state.

Materials scienceTime FactorsPhysics::OpticsPolarization-maintaining optical fiber02 engineering and technology01 natural sciencesMode-locked lasersPulse propagation and temporal solitonsLasers and laser optics010309 opticssymbols.namesake020210 optoelectronics & photonicsDouble-clad fiberOpticsFiber laserFiber optics and optical communications0103 physical sciences0202 electrical engineering electronic engineering information engineeringDispersion-shifted fiberOptical FibersMode volumebusiness.industryLasersReproducibility of ResultsSaturable absorptionModels TheoreticalPolarization (waves)Atomic and Molecular Physics and OpticssymbolsOptoelectronicsbusinessRaman scatteringOptics letters
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Passively mode-locked erbium-doped double-clad fiber laser operating at the 322nd harmonic

2009

International audience; We report passive mode locking of a soliton erbium-doped double-clad fiber laser operating at the 322nd harmonic of the fundamental cavity frequency. Repetition rates up to 3 GHz have been obtained with pulses of 1 ps duration and 18 pJ of energy. The supermode suppression at the 322nd harmonic is better than 25 dB. In addition, the transition dynamics from a bunched state of pulses to stable harmonic mode locking is presented, revealing a very long time scale.

Materials science[SDV]Life Sciences [q-bio]chemistry.chemical_elementPhysics::OpticsSoliton (optics)02 engineering and technology01 natural sciencesPulse propagation and temporal solitonslaw.invention010309 opticsErbiumDouble-clad fiberOpticslawFiber laser0103 physical sciencesUltrafast lasersbusiness.industryLasersDoping021001 nanoscience & nanotechnologyLaserAtomic and Molecular Physics and OpticschemistryMode-lockingHarmonic0210 nano-technologybusinessfiber
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Least-squares temporal difference learning based on an extreme learning machine

2014

Abstract Reinforcement learning (RL) is a general class of algorithms for solving decision-making problems, which are usually modeled using the Markov decision process (MDP) framework. RL can find exact solutions only when the MDP state space is discrete and small enough. Due to the fact that many real-world problems are described by continuous variables, approximation is essential in practical applications of RL. This paper is focused on learning the value function of a fixed policy in continuous MPDs. This is an important subproblem of several RL algorithms. We propose a least-squares temporal difference (LSTD) algorithm based on the extreme learning machine. LSTD is typically combined wi…

Mathematical optimizationArtificial neural networkArtificial IntelligenceCognitive NeuroscienceBellman equationReinforcement learningState spaceMarkov decision processTemporal difference learningComputer Science ApplicationsMathematicsExtreme learning machineCurse of dimensionalityNeurocomputing
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Using repeated ingestion to determine the effect of sweetness, viscosity and oiliness on temporal perception of soymilk astringency

1999

Abstract Astringency is a persistent sensation which increases upon repeated ingestion. To evaluate the effect of viscosity, sucrose and oil on perception of astringency during consumption of soymilk, a sequential sipping time–intensity (TI) procedure was utilized. For each soymilk, judges sipped the first of four ingestions and initiated the continuous recording of astringency intensity. Each sip was expectorated at 10 s after ingestion, and sipped 10 s after expectoration of the previous stimulus. After the fourth sample, judges rated astringency for 30 s. Traditional TI parameters, as well as rate of onset for each sip and increase in maximum intensity per sip were extracted from the TI …

Maximum intensity0303 health sciencesNutrition and DieteticsSucrose030309 nutrition & dieteticsChemistryOrganoleptic04 agricultural and veterinary sciences[SDV.IDA] Life Sciences [q-bio]/Food engineeringSweetness040401 food science03 medical and health scienceschemistry.chemical_compound0404 agricultural biotechnologySalivary lubrication[SDV.IDA]Life Sciences [q-bio]/Food engineeringIngestionContinuous recordingFood scienceTemporal perceptionComputingMilieux_MISCELLANEOUSFood Science
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Optimizing LUT-Based RTM Inversion for Semiautomatic Mapping of Crop Biophysical Parameters from Sentinel-2 and -3 Data: Role of Cost Functions

2014

Inversion of radiative transfer models (RTM) using a lookup-table (LUT) approach against satellite reflectance data can lead to concurrent retrievals of biophysical parameters such as leaf chlorophyll content (Chl) and leaf area index (LAI), but optimization strategies are not consolidated yet. ESA's upcoming satellites Sentinel-2 (S2) and Sentinel-3 (S3) aim to ensure continuity of old generation satellite sensors by providing superspectral images of high spatial and temporal resolution. This unprecedented data availability leads to an urgent need for developing robust, accurate, and operational retrieval methods. For three simulated Sentinel settings (S2-10 m: 4 bands, S2-20 m: 8 bands an…

Mean squared errorTemporal resolutionLookup tableRadiative transferGeneral Earth and Planetary SciencesSatelliteInversion (meteorology)Electrical and Electronic EngineeringLeaf area indexDivergence (statistics)Remote sensingMathematicsIEEE Transactions on Geoscience and Remote Sensing
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Quantifizierung von Atelektasen bei kontrollierter Beatmung: Spiral-CT versus dynamische Einzelschicht-CT

2004

Ziel: Dynamische CT-Untersuchungen (dCT) erlauben die Darstellung und Quantifizierung ventilierter Lungenflache und Atelektasenbildung wahrend kontinuierlicher Beatmung. Diese Studie ­vergleicht eine quantitative Auswertung einer infrakarinalen dCT-Einzelschicht mit der einer Spiral-CT der gesamten Lunge, um zu untersuchen, ob eine dynamisch gemessene Einzelschicht bezuglich der intrapulmonalen Atelektasenverteilung reprasentativ fur die Gesamtlunge ist. Material und Methoden: An 8 gesunden Schweinen erfolgte eine dCT (Schichtdicke 1 mm, zeitliches Inkrement 100 ms) wahrend kontinuierlicher Beatmung, gefolgt von einer Spiral-CT der gesamten Lunge (Schichtdicke 2 mm; Pitch 1,5; Inkrement 2 m…

Mechanical ventilationPathologymedicine.medical_specialtyLungbusiness.industrySlice thicknessSoftware toolmedicine.medical_treatmentAtelectasismedicine.diseasemedicine.anatomical_structureLung segmentationmedicineHigh temporal resolutionRadiology Nuclear Medicine and imagingDynamic ctNuclear medicinebusinessRöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren
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Spatial and Temporal Diversity During the Neolithic Spread in the Western Mediterranean: The First Pottery Productions

2017

Actual research into the neolithization process and the development of farming communities in the Western Mediterranean reveals a diverse and complex cultural landscape. Dispersal routes and rhythm of diffusion of the agro-pastoral economy, Mesolithic inheritance, regional interactions between communities, and functional adaptations all have to be explored to trace how Mediterranean societies were reshaped during this period. The different pottery traditions that accompany the Neolithic spread and its economic development are of course interconnected (the “impressed ware”), but they also show some degree of polymorphism. This variability has been variously interpreted, but rarely quantified…

Mediterranean climate010506 paleontology[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory060102 archaeologyEcologyCultural landscape06 humanities and the arts01 natural sciencesArchaeologyTemporal diversityGeographyPeriod (geology)Biological dispersal0601 history and archaeologyPotterySociocultural evolutionComputingMilieux_MISCELLANEOUSMesolithic0105 earth and related environmental sciences
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