Search results for "values."

showing 10 items of 1353 documents

Valence Topological Charge-Transfer Indices for Reflecting Polarity: Correction for Heteromolecules

2005

Valence topological charge-transfer (CT) indices are applied to the calculation of dipole moments mu. The mu calculated by algebraic and vector semisums of the CT indices are defined. The model is generalized for molecules with heteroatoms and corrected for sp(3)-heteromolecules. The ability of the indices for the description of the molecular charge distribution is established by comparing them with mu of the valence-isoelectronic series of cyclopentadiene, benzene and styrene. Two CT indices, mu(vec) (vector semisum of vertex-pair mu) and mu(vec)V (valence mu(vec)) are proposed. The mu(vec) behaviour is intermediate between mu(vec) and mu(experiment). The correction is produced in the corr…

Steric effectsHeteroatomBiophysicsPharmaceutical ScienceElectronsFluorescence PolarizationMolecular physicsArticleBiophysical PhenomenaAnalytical ChemistryValence topological charge-transfer indexElectronegativitylcsh:QD241-441Atomic orbitallcsh:Organic chemistryHeterocyclic CompoundsReference ValuesComputational chemistryDrug DiscoveryCharge distributionPhysical and Theoretical ChemistryTopological quantum numberDipole momentValence (chemistry)ChemistryOrganic ChemistryCharge densityBenzeneModels TheoreticalDipoleChemistry (miscellaneous)HeteroatomMolecular MedicineIsolelectroic seriesMolecules
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THE ROLE OF UNBOUNDED TIME-SCALES IN GENERATING LONG-RANGE MEMORY IN ADDITIVE MARKOVIAN PROCESSES

2013

Any additive stationary and continuous Markovian process described by a Fokker–Planck equation can also be described in terms of a Schrödinger equation with an appropriate quantum potential. By using such analogy, it has been proved that a power-law correlated stationary Markovian process can stem from a quantum potential that (i) shows an x-2 decay for large x values and (ii) whose eigenvalue spectrum admits a null eigenvalue and a continuum part of positive eigenvalues attached to it. In this paper we show that such two features are both necessary. Specifically, we show that a potential with tails decaying like x-μ with μ < 2 gives rise to a stationary Markovian process which is not p…

Stochastic processGeneral MathematicsAutocorrelationNull (mathematics)Mathematical analysisSpectrum (functional analysis)Quantum potentialstochastic processes survival probabilityGeneral Physics and AstronomyMarkov processStochastic processeSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Schrödinger equationsymbols.namesakelong range correlationsymbolsEigenvalues and eigenvectorsMathematicsFluctuation and Noise Letters
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Digital generation of multivariate wind field processes

2001

Abstract A very efficient procedure for the generation of multivariate wind velocity stochastic processes by wave superposition as well as autoregressive time series is proposed in this paper. The procedure starts by decomposing the wind velocity field into a summation of fully coherent independent vector processes using the frequency dependent eigenvectors of the Power Spectral Density matrix. It is shown that the application of the method allows to show some very interesting physical properties that allow to reduce drastically the computational effort. Moreover, using a standard finite element procedure for approximating the frequency dependent eigenvectors, the generation procedure requi…

Stochastic processMechanical EngineeringUnivariateAerospace EngineeringSpectral densityOcean EngineeringStatistical and Nonlinear PhysicsCondensed Matter PhysicsWind speedMatrix (mathematics)Superposition principleNuclear Energy and EngineeringAutoregressive modelCalculusApplied mathematicsSafety Risk Reliability and QualityEigenvalues and eigenvectorsCivil and Structural EngineeringMathematics
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Spectrochemical Rubidium-Strontium Method for Geological Age Determination

1960

The age values of lepidolites from South Africa and from Varutrask as well as that of a microcline from Varutrask have been determined and are discussed in connection with determination according to the potassium-argon method, applied to the same materials A method is suggested which allows the spectrochemical determination of Rb and Sr with sufficient accuracy. The isotopic composition is determined by means of a Fabry-Perot etalon and hollow-cathode excitation, investigating the hyper-fine structure of the Sr line at 4078 A.

StrontiumMicrocline010401 analytical chemistryAnalytical chemistrychemistry.chemical_elementMineralogyengineering.material01 natural sciencesIsotopic composition0104 chemical sciencesRubidium010309 opticschemistryAge values0103 physical sciencesengineeringInstrumentationSpectroscopyFabry–Pérot interferometerApplied Spectroscopy
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Kollokationen in Leserbriefen der Wochenzeitschrift Die Zeit

2020

Im Rahmen der Phraseologieforschung haben Kollokationen traditionell nur wenig Beachtung gefunden. Im Gegensatz zu Idiomen sind sie in der Regel semantisch transparent und bereiten daher Fremdsprachenlernern selten rezeptive Schwierigkeiten. Bei der Textproduktion muss jedoch die Problematik der Kollokationen beachtet werden. Aus diesem Grund halten wir Kollokationen für einen wichtigen Bereich der Phraseologie. Im vorliegenden Beitrag wird die Aufmerksamkeit auf die syntaktische Struktur, den Gebrauch und die Funktion von Kollokationen in 243 Leserbriefen der Zeitschrift Die Zeit gerichtet. Nach Heranziehung zweier Kollokationswörterbücher sowie einiger anderer Quellen konnten 278 Kollokat…

Studier av enskilda språkcontentskollokaatiotInhaltcollocateBasisSpecific LanguagesfraseologiaWertungletter to the editorLeserbriefvaluessaksan kielisisältöKollokatorphraseologyaikakauslehdetPhraseologie
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Use of middle cerebral velocity and blood pressure for the analysis of cerebral autoregulation at various frequencies: The coherence index

1998

A common component in many protocols for the evaluation of cerebral autoregulation is the comparison of transcranial Doppler ultrasound (TCD) velocities with blood pressure recordings, in which correlations between these two signals correspond to impaired autoregulation. With long data sets and complicated paradigms, however, visual inspection alone cannot adequately distinguish random coincidence from consistent correlation in a statistically valid fashion. We suggest and illustrate the use of the coherence index for this purpose. To illustrate this technique, long-term recordings of TCD velocity and blood pressure were obtained from 6 normal subjects and using 23 data segments from 8 pati…

Subarachnoid hemorrhageUltrasonography Doppler TranscranialHemodynamicsBlood PressureCerebral autoregulationCorrelationNuclear magnetic resonanceReference ValuesmedicineTidal VolumeHomeostasisHumansAutoregulationTranscranial doppler cerebral autoregulationMathematicsFourier AnalysisSettore MED/27 - NeurochirurgiaGeneral MedicineCoherence (statistics)Cerebral ArteriesSubarachnoid Hemorrhagemedicine.diseaseTranscranial DopplerPlethysmographyBlood pressureNeurologyAnesthesiaNeurology (clinical)Blood Flow VelocitySoftware
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Values of love: two forms of infinity characteristic of human persons

2020

AbstractIn his late reflections on values and forms of life from the 1920s and 1930s, Husserl develops the concept of personal value and argues that these values open two kinds of infinities in our lives. On the one hand personal values disclose infinite emotive depths in human individuals while on the other hand they connect human individuals in continuous and progressive chains of care. In order to get at the core of the concept, I will explicate Husserl’s discussion of personal values of love by distinguishing between five related features. I demonstrate that values of love (1) are rooted in egoic depts and define who we are as persons, (2) differ from objective values in being absolute …

SubjectivityPhilosophy of mindCognitive Neurosciencepersoonaintersubjectivityarvot (käsitykset)rakkaustunteetvaluesintersubjektiivisuusdevelopmenttimeminäTransitive relationpersonfenomenologiasubjektiivisuusEpistemologyPhilosophyHusserl EdmundinfinityEmotivevalue of love (Liebeswert)LiebeswertvocationPsychologyPhenomenology (psychology)IntersubjectivitylovePhenomenology and the Cognitive Sciences
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Existence, nonexistence and uniqueness of positive solutions for nonlinear eigenvalue problems

2017

We study the existence of positive solutions for perturbations of the classical eigenvalue problem for the Dirichlet $p-$Laplacian. We consider three cases. In the first the perturbation is $(p-1)-$sublinear near $+\infty$, while in the second the perturbation is $(p-1)-$superlinear near $+\infty$ and in the third we do not require asymptotic condition at $+\infty$. Using variational methods together with truncation and comparison techniques, we show that for $\lambda\in (0, \widehat{\lambda}_1)$ -$\lambda>0$ is the parameter and $\widehat{\lambda}_1$ being the principal eigenvalue of $\left(-\Delta_p, W^{1, p}_0(\Omega)\right)$ -we have positive solutions, while for $\lambda\geq \widehat{\…

Sublinear functionMonotonic functionLambda01 natural sciencesOmegaDirichlet distributionsymbols.namesakeFirst eigenvalueP-LaplacianUniqueness0101 mathematicsEigenvalues and eigenvectorsMathematical physicsNonlinear regularityPhysicsApplied Mathematics010102 general mathematicsMathematical analysisVariational methodAnalysiFirst eigenvalue; Generalized picone's identity; Nonlinear maximum principle; Nonlinear regularity; P-Laplacian; Variational methods; Analysis; Applied MathematicsGeneral Medicine010101 applied mathematicsp-LaplaciansymbolsNonlinear maximum principleGeneralized picone's identityAnalysis
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Molecular Search of New Active Drugs AgainstToxoplasma Gondii

1999

Molecular connectivity has been applied to the search of new compounds with activity against the protozoan Toxoplasma gondii, using a stepwise linear discriminant analysis (SLDA) which is able to classify a compound according its activity either as active or as inactive. Among the selected compounds, andrographolide and dibenzotiophene sulfone stand out, both with IC50 values lower than 1 microgram/ml, which are comparable to these of drugs such as sulfamethoxazole, pyrimethamine and trimethoprim, with IC50 values equal to 1.1, 0.04 and 2.31 micrograms/ml, respectively. These results confirm the usefulness of our topological approach for the selection and design of new-lead drugs active aga…

SulfamethoxazoleAndrographolideAntiprotozoal AgentsToxoplasma gondiiBioengineeringGeneral MedicinePharmacologyBiologybiology.organism_classificationVirologyTrimethoprimSulfonechemistry.chemical_compoundPyrimethaminechemistryparasitic diseasesDrug DiscoveryIc50 valuesmedicineAnimalsMolecular MedicineToxoplasmamedicine.drugSAR and QSAR in Environmental Research
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Determination of the object surface function by structured light: application to the study of spinal deformities.

1999

The projection of structured light is a technique frequently used to determine the surface shape of an object. In this paper, a new procedure is described that efficiently resolves the correspondence between the knots of the projected grid and those obtained on the object when the projection is made. The method is based on the use of three images of the projected grid. In two of them the grid is projected over a flat surface placed, respectively, before and behind the object; both images are used for calibration. In the third image the grid is projected over the object. It is not reliant on accurate determination of the camera and projector pair relative to the grid and object. Once the met…

Surface (mathematics)LightComputer scienceClassification of discontinuitiesSpinal Curvatureslaw.inventionOpticslawReference ValuesPhotographyHumansRadiology Nuclear Medicine and imagingComputer visionProjection (set theory)Radiological and Ultrasound Technologybusiness.industryPhantoms ImagingObject (computer science)GridSpineProjectorScoliosisCalibrationArtificial intelligenceSymmetry (geometry)businessStructured lightPhysics in medicine and biology
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