Search results for " basis"

showing 10 items of 224 documents

Radial Basis Function Interpolation for Referenceless Thermometry Enhancement

2015

MRgFUS (Magnetic Resonance guided Focused UltraSound) is a new and non-invasive technique to treat different diseases in the oncology field, that uses Focused Ultrasound (FUS) to induce necrosis in the lesion. Temperature change measurements during ultrasound thermo-therapies can be performed through magnetic resonance monitoring by using Proton Resonance Frequency (PRF) thermometry. It measures the phase variation resulting from the temperature-dependent changes in resonance frequency by subtracting one phase baseline image from actual phase. Referenceless thermometry aims to re-duce artefacts caused by tissue motion and frequency drift, fitting the back-ground phase outside the heated reg…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniProton resonance frequencyMaterials sciencemedicine.diagnostic_testbusiness.industryFrequency driftUltrasoundPhase (waves)Magnetic resonance imagingRadial Basis Function Interpolation Referenceless Thermometry Artificial Neural Network MRgFUS.Radial basis function interpolationmedicineRadial basis functionbusinessBiomedical engineeringInterpolation
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Sentence Induced Transformations in Conceptual Spaces

2008

The proposed work illustrates how "primitive concepts" can be automatically induced from a text corpus. The primitive concepts are identified by the orthonormal axis of a "conceptual" space induced by a methodology inspired to the latent semantic analysis approach. The methodology represents a natural language sentence by means of a set of rotations of an orthonormal basis in the "conceptual"space. The rotations, triggered by the sequence of words composing the sentence and realized by means of geometric algebra rotors, allow to highlight "conceptual" relations that can arise among the primitive concepts.

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniSequenceComputer sciencebusiness.industryLatent semantic analysisChatbots conceptual spaces LSA semantic computingWord processingData_MISCELLANEOUScomputer.software_genreGeometric algebraSemantic role labelingOrthonormal basisArtificial intelligencebusinesscomputerNatural languageNatural language processingSentence
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Difetto del nesso causale e manifesta insussistenza del fatto nel licenziamento per giustificato motivo oggettivo

2021

Con la sentenza n. 16253/2020 la Suprema Corte ha affermato che l’assenza di nesso causale tra la cessazione di un appalto e il licenziamento del lavoratore integra un’ipotesi di manifesta insussistenza del fatto posto alla base del licenziamento - con conseguente applicabilità della tutela reintegratoria attenuta di cui all’art. 18, comma 5, della legge n. 300/1970 - non riconducibile, pertanto, agli altri casi in cui il giudice dichiara risolto il rapporto concedendo la sola tutela indennitaria forte (da dodici a ventiquattro mensilità).

Settore IUS/07 - Diritto Del LavoroWith judgement no. 16253/2020 theSupremeCourt affirmed that the absence of causal linkbetween the termination of a contract and the dismissal of the worker integrates a hypothesis of manifest nonexistence of the fact at the basis of the dismissal with consequent applicability of the reinstatement protection afforded by art. 18 paragraph 5 of law no. 300/1970 and therefore does not fall within the other cases in which the judge declares the relationship terminated by granting an indemnity protection from twelve to twenty-four months salary.
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Polynomial mapped bases: theory and applications

2022

Abstract In this paper, we collect the basic theory and the most important applications of a novel technique that has shown to be suitable for scattered data interpolation, quadrature, bio-imaging reconstruction. The method relies on polynomial mapped bases allowing, for instance, to incorporate data or function discontinuities in a suitable mapping function. The new technique substantially mitigates the Runge’s and Gibbs effects.

Settore MAT/08 - Analisi Numericafake nodes Gibbs phenomenon mapped basis Runge's phenomenonmapped basisGibbs phenomenonRunge’s phenomenonfake nodesApplied MathematicsFOS: MathematicsMathematicsofComputing_NUMERICALANALYSISNumerical Analysis (math.NA)Mathematics - Numerical AnalysisIndustrial and Manufacturing Engineering
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Scritti in onore di Pellegrino Capaldo

2014

La qualità dei servizi è stata riconosciuta come un rilevante aspetto caratterizzante la performance dell’azienda pubblica, analogamente alla capacità di operare secondo criteri di efficienza e nel rispetto dei vincoli di bilancio. Sebbene sia possibile riscontrare alcuni significativi casi di adozione di politiche di customer satisfaction nelle amministrazioni pubbliche italiane, a tutt’oggi il tema presenta significative criticità, specialmente in ordine agli aspetti metodologici e agli strumenti operativi che consentano di integrare dette politiche nel sistema di programmazione e controllo delle aziende che erogano tali servizi. Il presente lavoro adotta una diversa prospettiva di analis…

Settore SECS-P/07 - Economia AziendaleQuality in delivering public services has been recognised as a major issue challenging performance in the public sector as well as the ability to operate effectively and within budget constraints. Empirical findings shown by the literature demonstrate that concrete efforts have been produced towards the evaluation and improvement of satisfaction levels of citizens and other Public Administration’s ‘customers’. However still today this issue portrays many unresolved criticalities particularly concerning the methodological approaches and operative tools to adopt in order to integrate ‘customer satisfaction’ programs with the wider organisational control system in each public administration. This paper adopts a non-conventional view of the ‘customer satisfaction’ concept. This is currently meant as a matter of social reporting or even statistical analysis based on the users’ perceptions on the level of provided services by a given (front office) unit in the public sector. Here an inter-institutional perspective is adopted with a view to map the overall value chain leading to the final product delivered to citizens or the community. Inside this chain tracking the underlying administrative products delivered by back-office units to their ‘internal clients’ in the public administration is recommended as a fundamental step to understand how to improve performance in satisfying citizens’ needs. This should also require a proper link between the administrative units’ goals and performance measures to the desired efficiency and effectiveness of processes leading to the attainment of administrative products providing the basis of the final services delivered to the private sector. Based on first empirical findings from field analysis in the Italian context the paper aims to outline an approach which could assist both politicians and managers to better assess and improve performance according to a customer satisfaction perspective.
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Spectrum cartography using adaptive radial basis functions: Experimental validation

2017

In this paper, we experimentally validate the functionality of a developed algorithm for spectrum cartography using adaptive Gaussian radial basis functions (RBF). The RBF are strategically centered around representative centroid locations in a machine learning context. We assume no prior knowledge about neither the power spectral densities (PSD) of the transmitters nor their locations. Instead, the received signal power at each location is estimated as a linear combination of different RBFs. The weights of the RBFs, their Gaussian decaying parameters and locations are jointly optimized using expectation maximization with a least squares loss function and a quadratic regularizer. The perfor…

Signal processingComputer scienceGaussianCentroid020206 networking & telecommunicationsContext (language use)02 engineering and technologyComputer Science::Computational GeometryLeast squaresComputer Science::Numerical Analysissymbols.namesakeExpectation–maximization algorithm0202 electrical engineering electronic engineering information engineeringsymbolsRadial basis functionLinear combinationCartography
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More wavelet-like orthonormal bases for the lowest Landau level: Some considerations

1994

In a previous work, Antoine and I (1994) have discussed a general procedure which 'projects' arbitrary orthonormal bases of L2(R) into orthonormal bases of the lowest Landau level. In this paper, we apply this procedure to a certain number of examples, with particular attention to the spline bases. We also discuss Haar, Littlewood-Paley and Journe bases.

Spline (mathematics)Pure mathematicsWaveletGeneral Physics and AstronomyHaarStatistical and Nonlinear PhysicsOrthonormal basisLandau quantizationSettore MAT/07 - Fisica MatematicaMathematical PhysicsMathematics
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Separatrix reconstruction to identify tipping points in an eco-epidemiological model

2018

Many ecological systems exhibit tipping points such that they suddenly shift from one state to another. These shifts can be devastating from an ecological point of view, and additionally have severe implications for the socio-economic system. They can be caused by overcritical perturbations of the state variables such as external shocks, disease emergence, or species removal. It is therefore important to be able to quantify the tipping points. Here we present a study of the tipping points by considering the basins of attraction of the stable equilibrium points. We address the question of finding the tipping points that lie on the separatrix surface, which partitions the space of system traj…

State variableMathematical optimizationRadial basis functionComputer scienceSeparatrixApplied MathematicsStable equilibriumComputational mathematics010103 numerical & computational mathematicsDynamical systemDynamical system01 natural sciences010101 applied mathematicsRegime shiftComputational MathematicsGroup huntingSettore MAT/08 - Analisi NumericaMoving Least Squares approximationAllee threshold; Dynamical system; Group hunting; Moving Least Squares approximation; Radial basis function; Regime shift; Computational Mathematics; Applied MathematicsRegime shiftPoint (geometry)Statistical physics0101 mathematicsMoving least squaresAllee threshold
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Block Based Deconvolution Algorithm Using Spline Wavelet Packets

2010

This paper presents robust algorithms to deconvolve discrete noised signals and images. The idea behind the algorithms is to solve the convolution equation separately in different frequency bands. This is achieved by using spline wavelet packets. The solutions are derived as linear combinations of the wavelet packets that minimize some parameterized quadratic functionals. Parameters choice, which is performed automatically, determines the trade-off between the solution regularity and the initial data approximation. This technique, which id called Spline Harmonic Analysis, provides a unified computational scheme for the design of orthonormal spline wavelet packets, fast implementation of the…

Statistics and ProbabilityApplied MathematicsSpline waveletCondensed Matter PhysicsDeconvolution · Wavelet packet · Spline · RegularityWavelet packet decompositionSpline (mathematics)Quadratic equationModeling and SimulationOrthonormal basisGeometry and TopologyComputer Vision and Pattern RecognitionDeconvolutionThin plate splineLinear combinationAlgorithmMathematics
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Generalized Riesz systems and orthonormal sequences in Krein spaces

2018

We analyze special classes of bi-orthogonal sets of vectors in Hilbert and in Krein spaces, and their relations with generalized Riesz systems. In this way, the notion of the first/second type sequences is introduced and studied. We also discuss their relevance in some concrete quantum mechanical system driven by manifestly non self-adjoint Hamiltonians.

Statistics and ProbabilityPure mathematics46N50 81Q12FOS: Physical sciencesGeneral Physics and AstronomyStatistical and Nonlinear PhysicsMathematical Physics (math-ph)Mathematics::Spectral TheoryRiesz basisBiorthogonal sequenceModeling and SimulationPT -symmetric HamiltonianKrein spaceOrthonormal basisSettore MAT/07 - Fisica MatematicaMathematical PhysicsMathematicsJournal of Physics A: Mathematical and Theoretical
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