Search results for "Probability Distribution"

showing 10 items of 263 documents

Radiomic analysis reveals DCE-MRI features for prediction of molecular subtypes of breast cancer.

2017

The purpose of this study was to investigate the role of features derived from breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and to incorporated clinical information to predict the molecular subtypes of breast cancer. In particular, 60 breast cancers with the following four molecular subtypes were analyzed: luminal A, luminal B, human epidermal growth factor receptor-2 (HER2)-over-expressing and basal-like. The breast region was segmented and the suspicious tumor was depicted on sequentially scanned MR images from each case. In total, 90 features were obtained, including 88 imaging features related to morphology and texture as well as dynamic features from tumor and …

OncologyCancer Treatmentlcsh:MedicineInvasive Ductal CarcinomaLogistic regression030218 nuclear medicine & medical imagingDiagnostic Radiology0302 clinical medicineMathematical and Statistical TechniquesBreast TumorsImage Processing Computer-AssistedMedicine and Health Scienceslcsh:ScienceMultidisciplinarymedicine.diagnostic_testHuman epidermal growth factorRadiology and ImagingMiddle AgedMagnetic Resonance ImagingOncology030220 oncology & carcinogenesisArea Under CurvePhysical SciencesFemaleAlgorithmsStatistics (Mathematics)Research ArticleAdultmedicine.medical_specialtyImaging TechniquesImage processingBreast NeoplasmsResearch and Analysis MethodsCarcinomasSkewness03 medical and health sciencesBreast cancerText miningDiagnostic MedicineInternal medicineImage Interpretation Computer-AssistedBreast CancermedicineBiomarkers TumorHumansStatistical MethodsDifferentiated TumorsAgedNeoplasm StagingReceiver operating characteristicbusiness.industrylcsh:RCancers and NeoplasmsMagnetic resonance imagingLuminal amedicine.diseaseImage EnhancementProbability TheoryProbability Distributionlcsh:QNeoplasm GradingbusinessMathematicsForecastingPloS one
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The Probability Law for Generic Density Operators

2020

In this chapter, the probability law of the non-null eigenstates of a generic density operator—studied in the previous chapter—is determined, by showing that given the composite system and the subsystem being considered, a mapping arises which associates a universal probability distribution to the non-null eigenstates of the generic density operator. We thus recover the Born statistical interpretation without having assumed it as a postulate.

Operator (computer programming)LawProbability distributionEigenvalues and eigenvectorsMathematicsInterpretation (model theory)
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Multicriteria Decision Analysis for Choosing the Remediation Method for a Landfill Based on Mixed Ordinal and Cardinal Information

2009

We describe a real-life application of a multicriteria method in the context of remediating a landfill in Finland. The landfill was used for dumping industrial waste during the years 1950 to 1965. During that time many harmful chemicals were stored in landfills among other waste. Therefore, this—and possibly several other—landfills have to be remediated. In this application, seven different remediation options were evaluated based on 13 criteria. For some criteria, cardinal measures with associated uncertainties were obtained. For other criteria, only ordinal (ranking) information was available. The problem was analyzed using the Stochastic Multicriteria Acceptability Analysis with Ordinal …

Ordinal dataMulticriteria decisionStochastic multicriteria acceptability analysisRankingOperations researchJoint probability distributionRank (computer programming)Context (language use)MathematicsVariety (cybernetics)
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Fitting random cash management models to data

2019

Abstract Organizations use cash management models to control balances to both avoid overdrafts and obtain a profit from short-term investments. Most management models are based on control bounds which are derived from the assumption of a particular cash flow probability distribution. In this paper, we relax this strong assumption to fit cash management models to data by means of stochastic and linear programming. We also introduce ensembles of random cash management models which are built by randomly selecting a subsequence of the original cash flow data set. We illustrate our approach by means of a real case study showing that a small random sample of data is enough to fit sufficiently goo…

Overdraft021103 operations researchGeneral Computer ScienceComputer science0211 other engineering and technologies02 engineering and technologyManagement Science and Operations ResearchComputer Science::Computers and SocietyProfit (economics)Modeling and Simulation0202 electrical engineering electronic engineering information engineeringEconometricsProbability distribution020201 artificial intelligence & image processingCash flowCash managementComputers & Operations Research
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A Unified Disk Scattering Model and Its Angle-of-Departure and Time-of-Arrival Statistics

2013

This paper proposes a novel probability density function (PDF) for the distribution of local scatterers inside a disk centered on the mobile station (MS). The new scattering model is introduced as the unified disk scattering model (UDSM), as it unifies a variety of typical circularly symmetric scattering models into one simple model. By adjusting a designated shape factor controlling the distribution of the scatterers, both the uniform circular and uniform ring scattering models can be obtained as special cases. Furthermore, the original Gaussian and uniform hollow-disk scattering models can be approximated with a high level of accuracy. In addition to these established scattering models, a…

PhysicsComputer Networks and CommunicationsScatteringGaussianMathematical analysisAerospace EngineeringProbability density functionsymbols.namesakeTime of arrivalDistribution (mathematics)Joint probability distributionAutomotive EngineeringsymbolsElectronic engineeringScattering theoryElectrical and Electronic EngineeringShape factorIEEE Transactions on Vehicular Technology
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Universal decay cascade model for dynamic quantum dot initialization.

2009

Dynamic quantum dots can be formed by time-dependent electrostatic potentials in nanoelectronic devices, such as gate- or surface-acoustic-wave-driven electron pumps. Ability to control the number of captured electrons with high precision is required for applications in fundamental metrology and quantum information processing. In this work we propose and quantify a scheme to initialize quantum dots with a controllable number of electrons. It is based on the stochastic decrease in the electron number of a shrinking dynamic quantum dot and is described by a nuclear decay cascade model with "isotopes" being different charge states of the dot. Unlike the natural nuclei, the artificial confineme…

PhysicsCondensed Matter - Mesoscale and Nanoscale PhysicsStrongly Correlated Electrons (cond-mat.str-el)FOS: Physical sciencesGeneral Physics and AstronomyInitializationCoulomb blockade02 engineering and technologyDecoupling (cosmology)Electron021001 nanoscience & nanotechnology01 natural sciencesComputational physicsCondensed Matter - Strongly Correlated ElectronsQuantum dotCascadeQuantum mechanicsMesoscale and Nanoscale Physics (cond-mat.mes-hall)0103 physical sciencesMaster equationProbability distribution010306 general physics0210 nano-technologyPhysical review letters
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Low-energy excitations from interacting tunneling units in the mean-field approximation

1991

Abstract The low-energy excitation spectrum of dilute concentrations of interacting tunneling quadrupoles randomly distributed in a non-polar medium was studied in the mean-field approximation. In particular the case of six-orientational tunneling quadrupoles (TQs) with a r−3 (elastic) interaction was considered. Because of the random position of the TQs, the internal field in a random variable and for relatively low concentrations has a Lorenzian probability distribution. The low-energy density of states is a constant and the low-energy excitations arise from the large internal fields, i.e. strongly interacting tunneling quadrupoles. The low-energy excitations were compared with those obta…

PhysicsCondensed matter physicsField (physics)Condensed Matter PhysicsElectronic Optical and Magnetic MaterialsMean field theoryMaterials ChemistryCeramics and CompositesDensity of statesVirial expansionProbability distributionAtomic physicsRandom variableQuantum tunnellingExcitationJournal of Non-Crystalline Solids
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Understanding and controlling N-dimensional quantum walks via dispersion relations: application to the two-dimensional and three-dimensional Grover w…

2013

The discrete quantum walk in N dimensions is analyzed from the perspective of its dispersion relations. This allows understanding known properties, as well as designing new ones when spatially extended initial conditions are considered. This is done by deriving wave equations in the continuum, which are generically of the Schrodinger type, and allows devising interesting behavior, such as ballistic propagation without deformation, or the generation of almost flat probability distributions, which is corroborated numerically. There are however special points where the energy surfaces display intersections and, near them, the dynamics is entirely different. Applications to the two- and three-d…

PhysicsContinuum (topology)General Physics and AstronomyFísicaSpaceType (model theory)Wave equationsymbols.namesakePerspective (geometry)Dispersion relationsymbolsProbability distributionQuantum walkStatistical physicsGrapheneSchrödinger's cat
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Experimental investigation of resonant activation

2000

We experimentally investigate the escape from a metastable state over a fluctuating barrier of a physical system. The system is switching between two states under electronic control of a dichotomous noise. We measure the escape time and its probability density function as a function of the correlation rate of the dichotomous noise in a frequency interval spanning more than 4 frequency decades. We observe resonant activation, namely a minimum of the average escape time as a function of the correlation rate. We detect two regimes in the study of the shape of the escape time probability distribution: (i) a regime of exponential and (ii) a regime of non-exponential probability distribution.

PhysicsHalf-normal distributionStatistical Mechanics (cond-mat.stat-mech)Physical systemFOS: Physical sciencesGeneral Physics and AstronomyProbability density functionSymmetric probability distributionNoise (electronics)Exponential functionProbability distributionStatistical physicsReciprocal distributionCondensed Matter - Statistical MechanicsPhysical review letters
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Studying the microlenses mass function from statistical analysis of the caustic concentration

2011

The statistical distribution of caustic crossings by the images of a lensed quasar depends on the properties of the distribution of microlenses in the lens galaxy. We use a procedure based in Inverse Polygon Mapping to easily identify the critical and caustic curves generated by a distribution of stars in the lens galaxy. We analyze the statistical distributions of the number of caustic crossings by a pixel size source for several projected mass densities and different mass distributions. We compare the results of simulations with theoretical binomial distributions. Finally we apply this method to the study of the stellar mass distribution in the lens galaxy of QSO 2237+0305.

PhysicsHistoryStellar massQuasarAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsGalaxyComputer Science ApplicationsEducationlaw.inventionLens (optics)StarslawPolygonProbability distributionAstrophysics::Earth and Planetary AstrophysicsCaustic (optics)Astrophysics::Galaxy AstrophysicsJournal of Physics: Conference Series
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