Search results for "Modula"

showing 10 items of 1481 documents

Self-organized modularization in evolutionary algorithms.

2005

The principle of modularization has proven to be extremely successful in the field of technical applications and particularly for Software Engineering purposes. The question to be answered within the present article is whether mechanisms can also be identified within the framework of Evolutionary Computation that cause a modularization of solutions. We will concentrate on processes, where modularization results only from the typical evolutionary operators, i.e. selection and variation by recombination and mutation (and not, e.g., from special modularization operators). This is what we call Self-Organized Modularization. Based on a combination of two formalizations by Radcliffe and Altenber…

Modularity (networks)education.field_of_studyTheoretical computer scienceComputer sciencebusiness.industryPopulationEvolutionary algorithmVariation (game tree)Modular designModels TheoreticalBiological EvolutionEvolutionary computationField (computer science)Computational MathematicsRange (mathematics)MutationArtificial intelligencebusinesseducationAlgorithmsEvolutionary computation
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Il sistema vivente: unità e modularità organica

2013

Discussione: Il sistema vivente: unità e modularità organica

Modularity Kant morphology
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On Fourier integral operators with Hölder-continuous phase

2018

We study continuity properties in Lebesgue spaces for a class of Fourier integral operators arising in the study of the Boltzmann equation. The phase has a H\"older-type singularity at the origin. We prove boundedness in $L^1$ with a precise loss of decay depending on the H\"older exponent, and we show by counterexamples that a loss occurs even in the case of smooth phases. The results can be seen as a quantitative version of the Beurling-Helson theorem for changes of variables with a H\"older singularity at the origin. The continuity in $L^2$ is studied as well by providing sufficient conditions and relevant counterexamples. The proofs rely on techniques from Time-frequency Analysis.

Modulation spaceApplied Mathematics010102 general mathematicsMathematical analysisShort-time Fourier transformPhase (waves)Hölder conditionFourier integral operators; modulation spaces; short-time Fourier transform; Analysis; Applied Mathematics01 natural sciencesBoltzmann equationFourier integral operatorMathematics - Functional Analysis010101 applied mathematicsSingularityshort-time Fourier transformFourier integral operators0101 mathematicsLp spacemodulation spacesMathematical PhysicsAnalysisMathematics
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Compactness of Fourier integral operators on weighted modulation spaces

2019

Using the matrix representation of Fourier integral operators with respect to a Gabor frame, we study their compactness on weighted modulation spaces. As a consequence, we recover and improve some compactness results for pseudodifferential operators.

Modulation spacePure mathematicsPseudodifferential operatorsApplied MathematicsGeneral Mathematics010102 general mathematicsMatrix representationGabor frame01 natural sciencesFourier integral operatorFunctional Analysis (math.FA)Mathematics - Functional Analysis35S30 47G30 42C15Compact spaceFOS: Mathematics0101 mathematicsMathematicsTransactions of the American Mathematical Society
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Quasi‐digital front‐ends for current measurement in integrated circuits with giant magnetoresistance technology

2014

In this study, the authors report on two different electronic interfaces for low-power integrated circuits electric current monitoring through current-to-frequency (I-f) conversion schemes. This proposal displays the intrinsic advantages of the quasi-digital systems regarding direct interfacing and self-calibrating capabilities. In addition, as current-sensing devices, they have made use of the giant magnetoresistance (GMR) technology because of its high sensitivity and compatibility with standard complementary metal oxide semiconductor processes. Single elements and Wheatstone bridges based on spin-valves and magnetic tunnel junctions have been considered. In this sense, schematic-level si…

ModulationResistive sensorsEngineeringWheatstone bridgebusiness.industryElectrical engineeringControl and Systems Engineering; Electrical and Electronic EngineeringIntegrated circuitsGiant magnetoresistance:Enginyeria electrònica::Microelectrònica::Circuits integrats [Àrees temàtiques de la UPC]Integrated circuitInterfacelaw.inventionPrinted circuit boardCMOSControl and Systems EngineeringlawInterfacingLow-power electronicsLow-powerCircuits integratsElectrical and Electronic EngineeringElectric currentbusinessIET Circuits, Devices & Systems
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Recursive Selective Harmonic Elimination for Multilevel Inverters: Mathematical Formulation and Experimental Validation

2023

A recursive method that eliminates +1 harmonics and their respective multiples from the output voltage of a cascaded H-bridge multilevel inverters with = 2 dc sources ( = 1, 2, 3,...) is proposed. It solves 2×2 linear systems with not singular matrices and always gives an exact solution with very low computational effort. Simulated results in three-phase five, nine, seventeen and thirty three level CHB inverters, and experimental results in five-level inverter demonstrate the validity of the method.

ModulationTotal Harmonic Distortion (THD)Multilevel InverterSelective Harmonics EliminationEnergy Engineering and Power TechnologyEfficiencySettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciElectrical and Electronic EngineeringMultilevel Inverter Modulation Selective Harmonics Elimination Total Harmonic Distortion (THD) EfficiencyIEEE Journal of Emerging and Selected Topics in Power Electronics
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Novel Isolated Multiple-Input Buck-Boost DC-DC Converter for Renewable Energy Sources

2021

An isolated multiple input dc-dc converter (MIC) with unidirectional buck-boost characteristics and simultaneous power transfer is proposed for multi-sources in renewable energy systems in this paper. When compared to existing isolated MICs, the proposed MIC significantly reduces the component count and control complexity since it requires a fixed coupled inductor with only one primary and secondary winding each for any number of inputs and does not require any phase-shifted pulse-width modulation. The operation of the proposed converter for simultaneous power transfer from multiple sources with varying voltages is numerically verified in simulation and validated on OPAL-RT’s OP5700 hardwar…

Modulationbusiness.industryElectromagnetic coilControl theoryComputer scienceBuck–boost converterMaximum power transfer theorembusinessInductorPhase modulationRenewable energyVoltageIECON 2021 – 47th Annual Conference of the IEEE Industrial Electronics Society
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On the performance of a linearized dual parallel Mach Zehnder electro-optic modulator

2014

The performance of a dual parallel differential Mach-Zehnder modulator broadband linearization architecture is analysed. This study provides experimental and analytical results showing an enhancement up to 20 dB in the 3rd-order intermodulation distortion factor at 5 GHz using RF and optical asymmetrical feeding factors.

ModulatorFOS: Physical sciencesPhysics::OpticsMach–Zehnder interferometerOpticsLinearizationBroadbandTEORIA DE LA SEÑAL Y COMUNICACIONESLinearisation techniquesElectrical and Electronic EngineeringPhysical and Theoretical ChemistryComunicació i tecnologiaMicrowave photonicsOptical fibre communicationsPhysicsbusiness.industryElectro-optic modulatorÒpticaAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsDual (category theory)Microwave photonicsbusinessOptics (physics.optics)IntermodulationPhysics - OpticsFibre radio
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Controlling the molecular diffusion in MOFs with the acidity of monocarboxylate modulators.

2021

The catalytic performance of metal-organic frameworks (MOFs) is related to their physicochemical properties, such as particle size, defect-chemistry and porosity, which synthetic control can be potentially achieved by coordination modulation. By combining PXRD, 1HNMR, FT-IR, N2 uptake measurements we have found insights that the different types of defects (missing linker or missing clusters consequence of the spatial distribution of missing linkers, and the combination of both) could be controlled by the type of modulator employed. We show that the molar percent of defects, either as missing linkers or as part of missing cluster defects, is related to the modulator’s acidity and subse…

Molecular diffusionMetal-Organic Frameworks Defects Coordination modulation Heterogeneous Catalysis010405 organic chemistryChemistry010402 general chemistry01 natural sciences0104 chemical sciencesCatalysisInorganic ChemistryChemical engineeringCluster (physics)Particle sizePorosityMesoporous materialLinkerPowder diffractionDalton transactions (Cambridge, England : 2003)
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Molecular modeling studies on dopamine-amino acid conjugates as potential dopaminergic modulators

2015

Molecular modeling dopamine-amino acid conjugates dopaminergic modulatorsSettore CHIM/08 - Chimica Farmaceutica
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