Search results for "Compact"

showing 10 items of 531 documents

Multilinear Fourier multipliers related to time–frequency localization

2013

We consider multilinear multipliers associated in a natural way with localization operators. Boundedness and compactness results are obtained. In particular, we get a geometric condition on a subset A⊂R2d which guarantees that, for a fixed synthesis window ψ∈L2(Rd), the family of localization operators Lφ,ψA obtained when the analysis window φ varies on the unit ball of L2(Rd) is a relatively compact set of compact operators.

Unit sphereMultilinear mapApplied MathematicsMathematical analysisCompact operatorCompact operator on Hilbert spaceTime–frequency analysissymbols.namesakeFourier transformCompact spaceRelatively compact subspacesymbolsAnalysisMathematicsJournal of Mathematical Analysis and Applications
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Optimal retraction problem for proper $k$-ball-contractive mappings in $C^m [0,1]$

2019

In this paper for any $\varepsilon >0$ we construct a new proper $k$-ball-contractive retraction of the closed unit ball of the Banach space $C^m [0,1]$ onto its boundary with $k < 1+ \varepsilon$, so that the Wośko constant $W_\gamma (C^m [0,1])$ is equal to $1$.

Unit spherePure mathematicsmeasure of noncompactneSettore MAT/05 - Analisi MatematicaApplied MathematicsBanach spaceRetraction ProblemBall (mathematics)proper mappingAnalysisRetractionMathematicsTopological Methods in Nonlinear Analysis
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VENTRICULAR DYSFUNCTION AND NUMBER OF NON COMPACTED SEGMENTS IN NON COMPACTION: NON-INDEPENDENT PREDICTORS

2009

VENTRICULAR DYSFUNCTION AND NUMBER OF NON COMPACTED SEGMENTS IN NON COMPACTION: NON-INDEPENDENT PREDICTORS BACKGROUND: Isolated ventricular noncompaction (IVNC) is characterized by multiple prominent trabeculations and deep intertrabecular recesses. Some reports prove that the chronic heart failure may occur in approximately half of the patients. In this report we investigate the correlation between the number of non compacted segments and entity of systolic dysfunction from the registry and subregistries of the SIEC. METHOD: To identify the correlation between ventricular dysfunction and number of segments involved in non compaction we evaluated a consecutive series of 238 patients affecte…

VENTRICULAR DYSFUNCTION AND NUMBER OF NON COMPACTED SEGMENTS IN NON COMPACTION: NON-INDEPENDENT PREDICTORS
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Conceptualisation et évaluation d'une typologie de lotissement vertical pour un aménagement urbain durable

2020

The current urban development process is the result of a paradoxical situation. On the one end, families prefer individual housing, which finds the favourable conditions to its spreading in the more or less distant from towns outskirts, while wishing to benefit from services (proximity to amenities, public transport offers, etc…) which are rather the corelate of dense urban centralization. On the other hand, in order to fight against environmental, social and economic costs of urban sprawl, and also aim towards a more sustainable city, the urban renovation and compact city projects lead to some density levels that only collective housing enables to reach. So, the equation - control of the u…

Ville durableTypologie d'habitat[SHS.GEO] Humanities and Social Sciences/GeographyUrban renewalLotissement vertical[SHS.GEO]Humanities and Social Sciences/GeographyForme urbaineUrban formVertical housing projectSustainable cityHousing typologyRenouvellement urbainCompact cityVille compacte
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Modelling the Water Retention Domain of a Compacted Scaly Clay

2012

A body of experimental data on the water retention behaviour of compacted samples of an Italian scaly clay is analysed. The mechanical and the hydraulic behaviour of compacted samples of this clay are governed by multi-scale arrangement of scales and aggregates, which characterises the compacted clay fabric. At least two different pore networks, namely intra-aggregate and inter-aggregate, may be identified, which interact one with the other along coupled hydro-mechanical paths. The retention behaviour is interpreted in the framework of a comprehensive multi-scale modelling approach recently proposed for compacted clays of low and medium activity, which proves to be able to account for the i…

Void ratioMaterials scienceSettore ICAR/07 - GeotecnicamedicineGeotechnical engineeringmedicine.symptomComposite materialretention behaviour compacted clay modellingDomain (software engineering)Water retention
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Innovative Compact Solar Air Conditioner based on Fixed and Cooled Adsorption Beds and Wet Heat Exchangers

2014

Abstract In this work, a new all-in-one compact solar air conditioner concept is presented. The system is mainly based on a new DEC process which utilises fixed and cooled adsorption beds operating in a batch process and two wet heat exchangers. The proposed innovative adsorption bed is a fin and tube heat exchanger commonly used in the air conditioning sector, wherein the spaces between the fins are filled with silica gel grains. The main feature of this component is to allow simultaneous dehumidification and cooling of air. Furthermore, since the component hosts a considerable amount of adsorption material, solar energy can be efficiently stored in the desiccant media in terms of accumula…

Waste managementChemistrybusiness.industryPlate heat exchangerAdsorption fixed and cooled bedThermal energy storageSolar energySolar air conditioningEnergy(all)Air conditioningThermodynamic cycleHeat exchangerAll-in-one compact solar air conditionerbusinessProcess engineeringDECEvaporative coolerEnergy Procedia
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Testing Soil Encasing Materials for Measuring Hydraulic Conductivity of a Sandy-Loam Soil by the Cube Methods

2008

The Cube Method (CM) and the Modified Cube Method (MCM) were developed for measuring vertical (K v ) and horizontal (K h ) saturated hydraulic conductivity of a single soil sample. By these methods, a cube of soil is carved out in situ and a suitable material is applied to enclose the cube in a tightly fitting casing before moving the sample to the laboratory. Problems may be associated with the use of gypsum, originally used to encase soil. The suitability of molten wax and expandable polyurethane foam to encase a soil cube was tested for a sandy-loam soil. Wax-treated samples yielded lower conductivity results than untreated samples by a maximum factor of 3.7. The observed discrepancies w…

WaxMaterials scienceGypsumSoil testSoil ScienceMineralogyConductivityengineering.materialSoil compaction (agriculture)Hydraulic conductivityLoamvisual_artvisual_art.visual_art_mediumengineeringSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliSaturated soil hydraulic conductivity cube methods expandable polyurethane foamComposite materialCasingSoil Science Society of America Journal
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MR2376860 (2009e:28048) Khurana, Surjit Singh Weak compactness of vector measures on topological spaces. Publ. Math. Debrecen 72 (2008), no. 1-2, 69-…

2009

Weak compactness of vector measures on topological spaces.

Weak compactness vector measures.
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Categorical foundations of variety-based topology and topological systems

2012

The paper considers a new approach to fuzzy topology based on the concept of variety and developed in the framework of topological theories resembling those of Rodabaugh. As a result, a categorical generalization of the notion of topological system of Vickers is obtained, and its theory unfolded, which clarifies the relations between algebra and topology. We also justify the use of semi-quantales as the basic underlying structure for doing lattice-valued topology as well as provide a categorical framework incorporating the theory of bitopological spaces.

Weak topologyArtificial IntelligenceLogicMathematics::General TopologyCompact-open topologyProduct topologyInitial topologyGeneral topologyTopological groupTopological spaceParticular point topologyTopologyMathematicsFuzzy Sets and Systems
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Reclaimed asphalt test specimen preparation assisted by image analysis

2015

This paper presents a laboratory investigation aimed at establishing a protocol for the production of homogeneous asphalt mixtures test specimens, incorporating reclaimed asphalt by using a gyratory compactor with coring and trimming works. Stone mastic asphalt specimens were compacted at the previously identified target densities with the final aim of obtaining specimens with a fixed and homogeneous air void distribution. A microstructural study was conducted to characterize the homogeneity in the air void distribution using X-ray computed tomography (CT) combined with image analysis techniques. The study concluded that the gyratory compactor is suitable for producing homogeneous test spec…

X-ray computed tomography (CT)Materials scienceBuilding and ConstructionStrength of materialsCoringImage analysisHomogeneousAsphaltMechanics of MaterialsHomogeneity (physics)General Materials ScienceGeotechnical engineeringTrimmingSpecimen preparationImage analysiRe-RoadMaterials Science (all)Composite materialGyratory compactorStone mastic asphaltReclaimed asphaltCivil and Structural Engineering
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