Search results for " interface"

showing 10 items of 1741 documents

Ellipsometric thickness and coverage of physisorbed layers of Xe, Kr, Ar and N2 on graphite

1990

Multilayer isotherms of Xe, Kr, Ar and N2 physisorbed on graphite (001) have been studied by ellipsometry. It is shown that the model of Dignam and Fedyk provides an excellent basis for the interpretation of the ellipsometric thickness in terms of the coverage and the polarizability of the admolecules. For N2 conclusions concerning the orientation of the molecule are drawn.

ArgonKryptonchemistry.chemical_elementMineralogyNoble gasSurfaces and InterfacesCondensed Matter PhysicsMolecular physicsSurfaces Coatings and FilmsXenonPhysisorptionchemistryEllipsometryPolarizabilityMaterials ChemistryGraphiteSurface Science
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Superficial defects induced by argon and oxygen bombardments on (110) TiO2 surfaces

1998

Abstract Compositional and chemical changes of titanium dioxide monocrystalline surfaces induced by bombardment with 4 keV argon and oxygen ions have been studied by AES, XPS and AFM. Argon ion bombardment induced strong changes in the composition and chemical state of the surface: loss of oxygen due to preferential sputtering occurred, and, related to this, Ti4+ species were reduced to Ti3+ and Ti2+. During oxygen bombardment, competition between preferential sputtering of oxygen ions of the oxide surface and oxygen implantation was observed. This phenomenon was found to be strongly dependent upon the incidence angle of the oxygen ions. Moreover, an oxygen bombardment with normal incidence…

ArgonOxidechemistry.chemical_elementSurfaces and InterfacesCondensed Matter PhysicsPhotochemistryOxygenSurfaces Coatings and FilmsMonocrystalline siliconCondensed Matter::Materials ScienceChemical statechemistry.chemical_compoundchemistryX-ray photoelectron spectroscopyPhysics::Plasma PhysicsSputteringTitanium dioxideMaterials Chemistrysense organsPhysics::Chemical PhysicsNuclear chemistrySurface Science
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FastEMD–CCA algorithm for unsupervised and fast removal of eyeblink artifacts from electroencephalogram

2020

Abstract Online detection and removal of eye blink (EB) artifacts from electroencephalogram (EEG) would be very useful in medical diagnosis and brain computer interface (BCI). In this work, approaches that combine unsupervised eyeblink artifact detection with empirical mode decomposition (EMD), and canonical correlation analysis (CCA), are proposed to automatically identify eyeblink artifacts and remove them in an online manner. First eyeblink artifact regions are automatically identified and an eyeblink artifact template is extracted via EMD, which incorporates an alternate interpolation technique, the Akima spline interpolation. The removal of eyeblink artifact components relies on the el…

Artifact (error)Cross-correlationmedicine.diagnostic_testComputer science0206 medical engineeringBiomedical EngineeringWord error rateHealth Informatics02 engineering and technologyElectroencephalography020601 biomedical engineeringHilbert–Huang transform[SPI]Engineering Sciences [physics]03 medical and health sciences0302 clinical medicineSignal ProcessingmedicineSpline interpolationAlgorithm030217 neurology & neurosurgeryInterpolationBrain–computer interfaceBiomedical Signal Processing and Control
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Online detection and removal of eye blink artifacts from electroencephalogram

2021

Abstract The most prominent type of artifact contaminating electroencephalogram (EEG) signals are the eye blink (EB) artifacts, which could potentially lead to misinterpretation of the EEG signal. Online identification and elimination of eye blink artifacts are crucial in applications such a Brain-Computer Interfaces (BCI), neurofeedback, and epilepsy diagnosis. In this paper, algorithms that combine unsupervised eye blink artifact detection (eADA) with modified Empirical Mode Decomposition (FastEMD) and Canonical Correlation Analysis (CCA) are proposed, i.e., FastEMD-CCA2 and FastCCA, to automatically identify eye blink artifacts and remove them in an online setting. The average accuracy, …

Artifact (error)medicine.diagnostic_testComputer sciencebusiness.industryBiomedical EngineeringWord error rateHealth InformaticsPattern recognitionElectroencephalographySignalHilbert–Huang transformSignal ProcessingmedicineArtificial intelligenceSensitivity (control systems)NeurofeedbackbusinessBrain–computer interfaceBiomedical Signal Processing and Control
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Automated and Online Eye Blink Artifact Removal from Electroencephalogram

2019

Eyeblink artifacts often contaminates electroencephalogram (EEG) signals, which could potentially confound EEG's interpretation. A lot offline methods are available to remove this artifact, but an online solution is required to remove eyeblink artifacts in near real time for EEG signal to be beneficial in applications such as brain computer interface, (BCI). In this work, approaches that combines unsupervised eyeblink artifact detection with Empirical Mode Decomposition (EMD) and Canonical Correlation Analysis (CCA) are proposed to automatically identify eyeblink artifacts and remove them in an online setting. The proposed approaches are analysed and evaluated in terms of artifact removal a…

Artifact (error)medicine.diagnostic_testComputer sciencebusiness.industryProcess (computing)Pattern recognition02 engineering and technologyElectroencephalography021001 nanoscience & nanotechnologySignalHilbert–Huang transform03 medical and health sciencesComputingMethodologies_PATTERNRECOGNITION0302 clinical medicinemedicineArtificial intelligence0210 nano-technologyCanonical correlationEye blinkbusiness030217 neurology & neurosurgeryBrain–computer interface2019 IEEE International Conference on Signal and Image Processing Applications (ICSIPA)
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Knowledge Acquisition in Conceptual Ontological Artificial Intelligence System

2009

The paper deals with active knowledge acquisition based on dialogue between AI system and its user. Presented method uses Conceptual Ontological Object Orientated System (COOS) to distinguish differences between concepts and to unequivocally process the input stream. In case of concepts, that do not exist in the system yet, adequate algorithms are being used to position them in ontological core. Separate concepts differ in attributes values or in sets of direct connections with other concepts. The communication aspect of the system deliver information that allow generating proper interpretation for userpsilas statement.

Artificial Intelligence SystemNatural language user interfacebusiness.industryComputer scienceInterpretation (philosophy)computer.software_genreKnowledge acquisitionSemantic networkKnowledge baseHuman–computer interactionOntologyArtificial intelligencebusinesscomputerNatural languageNatural language processing
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Stepping on invisible land: on the importance of communicating the value of soils.

2022

Soils play fundamental roles in the functioning of the Earth's ecosystems. Despite numerous initiatives to protect soils, it continues to be generally perceived as dirt or, at best, the surface we walk on. To better understand soil perception by the public, we conducted a survey with 99 participants from Poland and Brazil. We applied opportunity sampling and conducted semi-structured interviews with 40 respondents from Poland and 30 from Brazil, and 29 unstructured interviews in Brazil. Most of the respondents (53%) of the semi-structured interviews associated soil with the surface where plants grow, while 27% said that it is the ground we step on. When asked about pro-environmental campaig…

ArtistsArtistasSoilServiços ecossistêmicos do soloMoviesDivulgaçãoEcosystem servicesDisseminationSoil ecosystem serviceScience-practice interfaceInterface ciência-práticaFilmes
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Interannual variability of Greenland winter precipitation sources: 2. Effects of North Atlantic Oscillation variability on stable isotopes in precipi…

2008

[1] A new Lagrangian moisture source diagnostic is applied to identify the atmospheric conditions relevant for the fractionation of stable water isotopes during evaporation over the ocean and subsequent transport to Greenland. Northern Hemisphere winter months with positive and negative North Atlantic Oscillation (NAO) index are studied on the basis of ERA-40 reanalysis data. Diagnosed moisture transport conditions are supplied to a Rayleigh-type isotope fractionation model to derive estimates for the isotopic composition of stable isotopes in winter precipitation on the Greenland plateau for the two NAO phases. Because of changes in atmospheric circulation, moisture source locations for pr…

Atmospheric Science010504 meteorology & atmospheric sciencesδ18O0207 environmental engineeringSoil ScienceGreenland ice sheet02 engineering and technologyAquatic ScienceOceanography01 natural sciencesIsotope fractionationIce coreGeochemistry and PetrologyEarth and Planetary Sciences (miscellaneous)020701 environmental engineering[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environmentComputingMilieux_MISCELLANEOUS0105 earth and related environmental sciencesEarth-Surface ProcessesWater Science and Technology[SDU.OCEAN]Sciences of the Universe [physics]/Ocean AtmosphereEcologyStable isotope ratioNorthern HemispherePaleontologyForestrySea surface temperatureGeophysics13. Climate actionSpace and Planetary ScienceNorth Atlantic oscillationClimatologyEnvironmental science
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Particle size distributions of currently used pesticides in a rural atmosphere of France

2013

This work presents first data on the particle size distributions of current-used pesticides in the atmosphere. Ambient air samples were collected using a cascade impactor distributed into four size fractions in a rural site of Centre Region (France). Most pesticides were accumulated in the fine (0.1-1 mu m) particle size fraction such as cyprodinil, pendimethalin, fenpropidin, fenpropimorph and spiroxamine. Other pesticides such as acetochlor and metolachlor presented a bimodal distribution with maximum concentrations in the ultrafine (0.03-0.1 mu m) coarse (1-10 mu m) and in the ultrafine fine size ranges, respectively. No pesticides were detected in the size fraction >10 mu m. (C) 2013 El…

Atmospheric ScienceFenpropimorphAtmospheric concentrations010504 meteorology & atmospheric sciencesFraction (chemistry)Size distribution010501 environmental sciencesPesticide01 natural sciencesAtmospherePesticidePendimethalinchemistry.chemical_compoundchemistryEnvironmental chemistryEnvironmental scienceParticle sizeAcetochlor[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environmentMetolachlor0105 earth and related environmental sciencesGeneral Environmental Science
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Vegetation fire emissions and their impact on air pollution and climate

2009

Gaseous and particulate emissions from vegetation fires substantially modify the atmospheric chemical composition, degrade air quality and can alter weather and climate. The impact of vegetation fire emissions on air pollution and climate has been recognised in the late 1970s. The application of satellite data for fire-related studies in the beginning of the 21th century represented a major break through in our understanding of the global importance of fires. Today the location and extent of vegetation fires, burned area and emissions released from fires are determined from satellite products even though many uncertainties persist. Numerous dedicated experimental and modeling studies contri…

Atmospheric SciencePeat010504 meteorology & atmospheric sciencesMeteorologyAir pollutionWeather and climate010501 environmental sciencesmedicine.disease_cause01 natural sciences/dk/atira/pure/sustainabledevelopmentgoals/climate_actionEnvironmental protection11. SustainabilitymedicineSDG 13 - Climate ActionEnvironmental impact assessment[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environmentAir quality indexComputingMilieux_MISCELLANEOUS0105 earth and related environmental sciencesGeneral Environmental Science[SDU.OCEAN]Sciences of the Universe [physics]/Ocean AtmosphereVegetation15. Life on landParticulatesSeasonalitymedicine.disease13. Climate actionEnvironmental scienceAtmospheric Environment
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