Search results for "solution"

showing 10 items of 5638 documents

A fully automatic approach for multimodal PET and MR image segmentation in gamma knife treatment planning

2017

The aim of this study is to combine Biological Target Volume (BTV) segmentation and Gross Target Volume (GTV) segmentation in stereotactic neurosurgery.Our goal is to enhance Clinical Target Volume (CTV) definition, including metabolic and morphologic information, for treatment planning and patient follow-up.We propose a fully automatic approach for multimodal PET and MR image segmentation. This method is based on the Random Walker (RW) and Fuzzy C-Means clustering (FCM) algorithms. A total of 19 brain metastatic tumors, undergone stereotactic neuro-radiosurgery, were retrospectively analyzed. A framework for the evaluation of multimodal PET/MRI segmentation is presented, considering volume…

Radiotherapy PlanningBrain tumorHealth Informatics02 engineering and technologyFuzzy C-means clusteringRadiosurgeryBrain tumorsMultimodal ImagingING-INF/05 - SISTEMI DI ELABORAZIONE DELLE INFORMAZIONI030218 nuclear medicine & medical imaging03 medical and health sciencesComputer-Assisted0302 clinical medicineRandom walker algorithm0202 electrical engineering electronic engineering information engineeringHumansMedicineSegmentationComputer visionRadiation treatment planningCluster analysisImage resolutionPET/MR imagingModality (human–computer interaction)Brain Neoplasmsbusiness.industryRadiotherapy Planning Computer-AssistedINF/01 - INFORMATICAMultimodal therapymedicine.diseaseRandom Walker algorithmMagnetic Resonance ImagingComputer Science ApplicationsBrain tumorGamma knife treatmentPositron-Emission Tomography020201 artificial intelligence & image processingMultimodal image segmentationBrain tumors; Fuzzy C-means clustering; Gamma knife treatments; Multimodal image segmentation; PET/MR imaging; Random Walker algorithm; Brain Neoplasms; Humans; Radiosurgery; Magnetic Resonance Imaging; Multimodal Imaging; Positron-Emission Tomography; Radiotherapy Planning Computer-AssistedArtificial intelligencebusinessGamma knife treatmentsSoftware
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Impact of rainfall data resolution in time and space on the urban flooding evaluation

2012

ABSTRACT Climate change and the modification of urban environment increase the frequency and the impact of flooding rising the interest of researchers and practitioners on this topic. Usually flooding frequency analysis in urban areas are indirectly carried out by adopting advanced hydraulic models to simulate long historical rainfall series or design storms. However their results are affected by a grade of uncertainty which has been much investigated in recent years. One of the most critical source of uncertainty inherent to hydraulic model results is linked to the imperfect knowledge of the rainfall input data both in time and space. Several studies show that hydrological modelling in urb…

Rainfall resolution rainfall-runoff transformation urban drainage modelling
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Water status modelling : impact of local rainfall variability in Burgundy (France)

2016

6 pages; International audience; Water status is a key factor in vine development and berry ripening. Water status is strongly affected byenvironmental parameters such as soil and climate. Whereas at local scale the soil variability is frequentlyaccounted for, little scientific reports are available concerning the impact of local rainfall variability ongrapevine water status. In order to accurately register the space and time variations of rainfall at local scale, adense rain-gauges network has been installed in Burgundy. It is composed of 45 rain-gauges over a 28 km² area.Rainfall data collected by each rain-gauge in 2014 and 2015 was used as input variables in the grapevine waterbalance m…

Rainfall[SDU.STU.CL] Sciences of the Universe [physics]/Earth Sciences/Climatology[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology[SDV.BV]Life Sciences [q-bio]/Vegetal BiologyComputingMethodologies_GENERAL[ SDU.STU.CL ] Sciences of the Universe [physics]/Earth Sciences/ClimatologyHigh ResolutionBurgundyComputingMilieux_MISCELLANEOUSWater statusModel
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Characterization of the 3D information of Calyptogena shells

2003

We propose in this paper an application of multiresolution analysis techniques to extract information contained in the growth increments of a bivalve mollusk called: Calyptogena . The first stage consists in extracting a range image of the mollusk’s shell using a 3-D scanner. Applying a multiresolution analysis enables us to localize precisely those growth increments by preserving relevant details. Moreover, interesting spatial and frequency properties of the multiresolution analysis underline information contained on the shell. Intra-individual variation and inter-individual variations are compared to assume some conclusions as for the ontogenetic evolution of the animal such as periodicit…

Range (mathematics)WaveletGeographyBivalve molluskbusiness.industryComputer graphics (images)Multiresolution analysisShell (structure)Image acquisition3D modelingbusinessBiological systemCharacterization (materials science)SPIE Proceedings
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A Universal and Sensitive Method for Gas Chromatographic Determination of Volatile Substrates and Metabolites

1978

The concentration of solutes from aqueous solutions in the μl range is still a problem in gas chromatographic trace analysis (e.g. J.S. Fritz, Acc. Chem. Res. 10, 67, 1977).

Range (particle radiation)Aqueous solutionChromatographyChemistryAnalytical chemistryTrace analysisAnticoagulant activity
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Heat Capacity and Dielectric Properties of the PNN-PT Ferroelectric Ceramics

2012

A study of dielectric permittivity and heat capacity of the (1-х)PbNi1/3Nb2/3O3 – хPbTiO3 solid solution system (x = 0.3, 0.4, 0.5) within the 290–700 K range is reported. Temperatures of phase transitions Tm determined from maximums of dielectric permittivity ϵ depends on the content of PbTiO3. A broad phase transition is shown to proceed in the 0.7PbNi1/3Nb2/3O3–0.3PbTiO3 composition around 312 K. Specific to phase transitions anomalous heat capacity is observed at Т ≈ 520 K in all compositions studied.

Range (particle radiation)Phase transitionMaterials scienceCondensed matter physicsFerroelectric ceramicsDielectric permittivityThermodynamicsRelative permittivityDielectricCondensed Matter PhysicsHeat capacityElectronic Optical and Magnetic MaterialsSolid solutionFerroelectrics
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Thermal properties of ferroelectric 0.7PbNi1/3Nb2/3O3–0.3PbTiO3ceramics

2013

A study of heat capacity as function of temperature of the 0.7PbNi1/3Nb2/3O3–0.3PbTiO3 solid solution within the 120–800 K range is reported. Broad anomalies on the curve of heat capacity are revealed in the 250–450 K and 450–650 K intervals peaking at 520 K and a λ-anomaly at T ≈ 225 K. Results are discussed with account for dielectric and structural data.

Range (particle radiation)Phase transitionMaterials scienceCondensed matter physicsThermodynamicsDielectricHeat capacityFerroelectricityvisual_artThermalvisual_art.visual_art_mediumGeneral Materials ScienceCeramicInstrumentationSolid solutionPhase Transitions
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Analysis of small-angle scattering patterns from a commercial Al-Li alloy by means of a model incorporating a repulsive step potential

1992

Abstract Small-angle X-ray scattering measurements are reported for a commercial Al-8·49%Li-51% Cu (atomic composition) alloy solution treated at 520°C and thermally aged for several times at several temperatures. Data have been analysed by means of a model of ellipsoidal precipitate particles previously proposed by some of us and by a modification of this model where, in the interparticle interference term, allowance is made for interactions between the precipitate particles at longer range than previously. This was achieved by the introduction, in addition to the hard-sphere interaction potential, of a potential step. Our fits indicate that the precipitate particles interact through a rep…

Range (particle radiation)ScatteringChemistryGeneral Chemical EngineeringAlloyGeneral Physics and AstronomyThermodynamicsActivation energyengineering.materialThermal diffusivitySolution of Schrödinger equation for a step potentialCrystallographyengineeringParticleSmall-angle scatteringPhilosophical Magazine B
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Rational Solutions to the KdV Equation in Terms of Particular Polynomials

2022

Here, we construct rational solutions to the KdV equation by particular polynomials. We get the solutions in terms of determinants of the order n for any positive integer n, and we call these solutions, solutions of the order n. Therefore, we obtain a very efficient method to get rational solutions to the KdV equation, and we can construct explicit solutions very easily. In the following, we present some solutions until order 10.

Rational solution[MATH] Mathematics [math]PolynomialBilinear differential operator
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Dry synthesis of B-MFI, MTN- and MTW-type materials

1997

Abstract B-MFI and MTN-type materials were synthesized via the fluoride route from dry powders in the complete absence of a solution phase. Amorphous precursors obtained by drying SiO 2 · Al 2 O 3 gels at 700°C were transformed into MTN-type material in the presence of dried NH 4 F and TMACl. Amorphous precursors obtained by drying SiO 2 gels at 700°C were transformed into B-MFI in the presence of dried NH 4 F, B 2 O 3 and TPABr. Water is formed as a reaction product. However, the water vapor pressure is appreciably below the water vapor saturation pressure under the given reaction conditions. In addition, syntheses using seed crystals were carried out successfully.

Reaction conditionsMaterials scienceChromatographyVapor pressureVapour pressure of waterGeneral EngineeringGeneral ChemistrySolution phaseAmorphous solidchemistry.chemical_compoundchemistryChemical engineeringGeneral Materials ScienceFluorideWater vaporSeed crystalMicroporous Materials
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