Search results for "algorithm"

showing 10 items of 4887 documents

Periodic Orthogonal Wavelets and Wavelet Packets

2018

In this chapter, we discuss how to derive versatile families of periodic discrete-time orthogonal wavelets and wavelet packets from discrete and discrete-time splines outlined in Chap. 3. These wavelets and wavelet packets, although not having compact supports, are well localized in the time domain. They can have any number of discrete vanishing moments. Their DFT spectra tend to have a rectangular shape when the spline order grows and provide a collection of refined splits of the Nyquist frequency band. The wavelet and wavelet packet transforms are implemented in a fast way using the FFT.

Spline (mathematics)WaveletComputer scienceNetwork packetFast Fourier transformComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONMathematicsofComputing_NUMERICALANALYSISData_CODINGANDINFORMATIONTHEORYTime domainVanishing momentsNyquist frequencyAlgorithmWavelet packet decomposition
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Two-Dimensional Orthogonal Wavelets and Wavelet Packets

2018

This chapter extends the design of spline-based orthogonal discrete-time wavelets and wavelet packets to two-dimensional case. The corresponding transforms are implemented by using the 2D FFT.

Spline (mathematics)WaveletComputer sciencePhase spectrumFast Fourier transformMathematicsofComputing_NUMERICALANALYSISAlgorithmWavelet packet decomposition
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Discrete-Time Periodic Wavelet Packets

2014

Direct and inverse wavelet and wavelet packet transforms of a spline are implemented by filtering the spline’s coordinates by two-channel critically sampled p-filter banks. In this chapter, those p-filter banks are utilized for processing discrete-time signals. The p-filter banks generate discrete-time wavelets and wavelet packets in the spaces of 1D and 2D periodic signals.

Spline (mathematics)WaveletDiscrete time and continuous timeComputer scienceNetwork packetMathematicsofComputing_NUMERICALANALYSISInverseData_CODINGANDINFORMATIONTHEORYAlgorithmWavelet packet decomposition
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Some efficient algorithms for the solution of a single nonlinear equation

1981

High order methods for the numerical solution of nonlinear scalar equations are proposed which are more efficient than known procedures, and a unified approach to various methods suggested in literature is given.

Split-step methodNonlinear systemComputational Theory and MathematicsEfficient algorithmApplied MathematicsMathematical analysisScalar (mathematics)Order of accuracyHigh orderComputer Science ApplicationsNumerical stabilityLocal convergenceMathematicsInternational Journal of Computer Mathematics
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Strengthened splitting methods for computing resolvents

2021

In this work, we develop a systematic framework for computing the resolvent of the sum of two or more monotone operators which only activates each operator in the sum individually. The key tool in the development of this framework is the notion of the “strengthening” of a set-valued operator, which can be viewed as a type of regularisation that preserves computational tractability. After deriving a number of iterative schemes through this framework, we demonstrate their application to best approximation problems, image denoising and elliptic PDEs. FJAA and RC were partially supported by the Ministry of Science, Innovation and Universities of Spain and the European Regional Development Fund …

Splitting algorithmControl and Optimization0211 other engineering and technologies47H05 90C30 65K05Elliptic pdesMonotonic function02 engineering and technology01 natural sciencesMonotone operatorOperator (computer programming)Development (topology)Estadística e Investigación OperativaFOS: Mathematics0101 mathematicsImage denoisingResolventMathematics - Optimization and ControlMathematicsResolvent021103 operations researchApplied Mathematics010102 general mathematicsAlgebraComputational MathematicsMonotone polygonOptimization and Control (math.OC)StrengtheningKey (cryptography)Computational Optimization and Applications
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Treatment algorithm for spontaneous spinal infections: A review of the literature

2019

Background: Primary spinal infections are rare pathologies with an estimated incidence of 5% of all osteomyelitis. The diagnosis can be challenging and this might result in a late identification. The etiological diagnosis is the primary concern to determine the most appropriate treatment. The aim of this review article was to identify the importance of a methodological attitude toward accurate and prompt diagnosis using an algorithm to aid on spinal infection management. Methods: A search was done on spinal infection in some databases including PubMed, ISI Web of Knowledge, Google Scholar, Ebsco, Embasco, and Scopus. Results: Literature reveals that on the basis of a clinical suspicion, the…

SpondylodiscitisPercutaneouslcsh:Diseases of the musculoskeletal systemDiscitisEpidural abscessDiscitiReview Article03 medical and health sciences0302 clinical medicineprimary spinal infectionsDeformityMedicine030222 orthopedicsbusiness.industryOsteomyelitismedicine.diseaseReview articleEtiologyDiscitisSurgeryNeurology (clinical)spondylodiscitismedicine.symptomlcsh:RC925-935businessAlgorithm030217 neurology & neurosurgeryprimary spinal infectionJournal of Craniovertebral Junction & Spine
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Signal detection for spread spectrum communication systems with gradient algorithm

2012

Retrieval process of original symbols of a spread spectrum based communication system is tried to be improved by Gradient Algorithm (GA) and Blind Source Separation (BSS) principles. Two simple schemes, based on two energy functions are presented. Time correlation properties of the channel are used as advantages in developing the filter coefficients for the receiver. Direct Sequence - Code Division Multiple Access (DS-CDMA) technique based system setup is used for algorithm testing purposes. This is identified as one of the most stable spread spectrum communication technique where most of the technologies developed for that are highly compatible with High Speed Packet Access (HSPA) transmis…

Spread spectrumHigh Speed Packet AccessTransmission (telecommunications)Computer scienceCode division multiple accessDirect-sequence spread spectrumCommunications systemChipAlgorithmBlind signal separation2012 IEEE 8th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob)
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Interference excision algorithm for frequency hopping spread spectrum based on undecimated wavelet packet transform

2002

An algorithm for reducing narrowband interference effects in frequency hopping spread spectrum is presented. The method is based on the undecimated wavelet packet transform. It improves the performance obtained by other methods. Experimental results demonstrate the suitability of the algorithm.

Spread spectrumInterference excisionComputer scienceComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSComputer Science::Networking and Internet ArchitectureElectronic engineeringFrequency-hopping spread spectrumElectrical and Electronic EngineeringAlgorithmWavelet packet decompositionElectronics Letters
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Transitivity in coherence-based probability logic

2016

We study probabilistically informative (weak) versions of transitivity by using suitable definitions of defaults and negated defaults in the setting of coherence and imprecise probabilities. We represent p-consistent sequences of defaults and/or negated defaults by g-coherent imprecise probability assessments on the respective sequences of conditional events. Moreover, we prove the coherent probability propagation rules for Weak Transitivity and the validity of selected inference patterns by proving p-entailment of the associated knowledge bases. Finally, we apply our results to study selected probabilistic versions of classical categorical syllogisms and construct a new version of the squa…

Square of oppositionSettore MAT/06 - Probabilita' E Statistica MatematicaTheoretical computer scienceLogicInferenceSquare of oppositionProbability logicSettore M-FIL/02 - Logica E Filosofia Della Scienza02 engineering and technologyComputer Science::Artificial Intelligence0603 philosophy ethics and religion0202 electrical engineering electronic engineering information engineeringGeneralized coherenceCategorical variableMathematicsTransitivityTransitive relationApplied MathematicsDefaultProbabilistic logicSyllogism06 humanities and the artsCoherence (statistics)Settore MAT/01 - Logica MatematicaImprecise probabilityp-EntailmentSyllogism060302 philosophyImprecise probabilityp-Consistency020201 artificial intelligence & image processingCoherenceAlgorithmJournal of Applied Logic
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A branch-and-cut algorithm for the soft-clustered vehicle-routing problem

2021

Abstract The soft-clustered vehicle-routing problem is a variant of the classical capacitated vehicle-routing problem (CVRP) in which customers are partitioned into clusters and all customers of the same cluster must be served by the same vehicle. We introduce a novel symmetric formulation of the problem in which the clustering part is modeled with an asymmetric sub-model. We solve the new model with a branch-and-cut algorithm exploiting some known valid inequalities for the CVRP that can be adapted. In addition, we derive problem-specific cutting planes and new heuristic and exact separation procedures. For square grid instances in the Euclidean plane, we provide lower-bounding techniques …

Square tilingHeuristic (computer science)Applied Mathematics0211 other engineering and technologies021107 urban & regional planning0102 computer and information sciences02 engineering and technology01 natural sciencesTravelling salesman problemReduction (complexity)010201 computation theory & mathematicsVehicle routing problemBenchmark (computing)Discrete Mathematics and CombinatoricsCluster analysisBranch and cutAlgorithmMathematicsDiscrete Applied Mathematics
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