Search results for "Compact"

showing 10 items of 531 documents

Growth pattern of underlithified strata during thrust-related folding

2004

Abstract Asymmetric anticlines with overturned or steeply dipping forelimbs and gently dipping backlimbs are generally interpreted as thrust-related folds. Fold asymmetry occurs as a consequence of forelimb rotation. If deformation takes place in environments dominated by submarine sedimentation, the limbs coincide with the slope (depositional surface) and rotation reflects slope steepening. If folds are nucleated in poorly or unlithified deposits, growth geometry also depends on the properties of the media, such as cohesion and the angle of internal friction. For cohesionless deposits, the tilting of the slope influences the equilibrium of the soft sediments, resulting in gravity-driven fl…

Sedimentary depositional environmentBeddingCompactionAnticlineGeologyFold (geology)NeogenePetrologyLithificationGeomorphologyGeologySoft-sediment deformations Stratal pattern Fold growth Thrust tectonics Pliocene SicilyThrust tectonics
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Analysis of a parabolic cross-diffusion population model without self-diffusion

2006

Abstract The global existence of non-negative weak solutions to a strongly coupled parabolic system arising in population dynamics is shown. The cross-diffusion terms are allowed to be arbitrarily large, whereas the self-diffusion terms are assumed to disappear. The last assumption complicates the analysis since these terms usually provide H 1 estimates of the solutions. The existence proof is based on a positivity-preserving backward Euler–Galerkin approximation, discrete entropy estimates, and L 1 weak compactness arguments. Furthermore, employing the entropy–entropy production method, we show for special stationary solutions that the transient solution converges exponentially fast to its…

Self-diffusioneducation.field_of_studyKullback–Leibler divergenceRelative entropyStrong cross-diffusionApplied MathematicsMathematical analysisPopulationLong-time behavior of solutionsWeak competitionArbitrarily largeCompact spaceExponential growthPopulation modelEntropy (information theory)Global-in-time existence of weak solutionseducationPopulation equationsAnalysisMathematicsJournal of Differential Equations
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On Determinants of Integrable Operators with Shifts

2013

Integrable integral operator can be studied by means of a matrix Riemann--Hilbert problem. However, in the case of so-called integrable operators with shifts, the associated Riemann--Hilbert problem becomes operator valued and this complicates strongly the analysis. In this note, we show how to circumvent, in a very simple way, the use of such a setting while still being able to characterize the large-$x$ asymptotic behavior of the determinant associated with the operator.

Semi-elliptic operatorPure mathematicsOperator (computer programming)Multiplication operatorIntegrable systemGeneral MathematicsMathematical analysisFinite-rank operatorOperator theoryCompact operatorMathematicsQuasinormal operatorInternational Mathematics Research Notices
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Mapping soil compaction measuring cone penetrometer resistance

2003

The quickest way for monitoring soil compaction differences in a field is measuring cone penetrometer resistance. Soil compaction can be significantly spatially variable, depending on the amount and distribution of the traffic of agricultural machines in the field. Therefore, it could be useful to measure soil compaction on a localised basis, in order to produce maps of the damages caused by the traffic of agricultural machines and/or the action of tillage implements. Aim of this paper is to present a system developed by the Department I.T.A.F. for the geo-referenced measurement of cone penetrometer resistance and for mapping soil compaction. This system was built fitting a minitransporter …

Settore AGR/09 - Meccanica AgrariaSoil compaction cone penetrometer resistance agricultural machine traffic DGPS maps
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Systems for evaluating the correlation between soil cone penetrometer resistance and shear strength

2008

The aim of this research is to study possible correlations between soil compaction (and related soil cone penetrometer resistance measurements) and shear strength normal to the field plane, required to cut the soil with a subsoiler. A measurement system for sensing the soil cone penetrometer resistance was built mounting, on a frame fixed to the front part of a tractor, a rod and a penetration cone with a load cell. A load cell, mounted on the tractor drawbar, pulling a subsoiler, allowed to measure the shear strength normal to the field plane, required to cut the soil. Both load cells were connected, through a display, to a portable computer, where a software was used for acquiring the dat…

Settore AGR/09 - Meccanica Agrariasoil compaction shear strength cone penetrometer resistance
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Isolated non-compaction, stroke and trabecular meshwork fibrosis

2009

Settore BIO/17 - IstologiaNon compaction Stroke Fibrosis Recesses
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Role of Stress History on the Swelling-Shrinkage Behavior of Compacted Scaly Clay

2022

Compacted scaly clays are complex geomaterials widely used for the realization of dam cores and waste dump liners. This research aims to investigate the swelling/shrinkage behavior of these geomaterials subjected in an oedometric cell to complex hydromechanical stress paths, including different sequences of cyclic variations of suction and stress. Microstructure investigations, based on scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP) techniques, highlighted the microstructural characteristics of the material, which are the distinctive microfabric features (particles assemblages and scales) and the double-porosity networks, where micro- and macropores coexist. More…

Settore ICAR/07 - GeotecnicaSoil ScienceCompacted clay Loading/unloading paths Over-consolidation ratio Suction-controlled test Wetting/drying cycles
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The void ratio dependency of the retention behaviour for a compacted scaly clay

2010

Settore ICAR/07 - Geotecnicacompacted scaly clay retention curves void ratio
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Electron structure, ultra-dense hydrogen and low energy nuclear reactions

2019

In this paper, a simple Zitterbewegung electron model, proposed in a previous work, is presented from a different perspective based on the principle of mass- frequency equivalence. A geometric- electromagnetic interpretation of mass, relativistic mass, De Broglie wavelength, Proca, Klein- Gordon, Dirac and Aharonov- Bohm equations in agreement with the model is proposed. A non-relativistic, Zitterbewegung interpretation of the 3.7 keV deep hydrogen level found by J. Naudts is presented. According to this perspective, ultra-dense hydrogen can be conceived as a coherent chain of bosonic electrons with protons or deuterons located in the center of their Zitterbewegung orbits. This approach sug…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniSettore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciUltra-dense hydrogenAharonov-Bohm equationDe Broglie wavelengthJosephson constantZitterbewegungSettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciCompact structureElectron structureLENRNatural unitProca equationHeisenberg's uncertainty principlerelativistic maAneutronic and many-body low energy nuclear reactionKlein-Gordon equationDirac equationESR
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On compact Just-Non-Lie groups

2007

A compact group is called a compact Just-Non-Lie group or a compact JNL group if it is not a Lie group but all of its proper Hausdorff quotient groups are Lie groups. We show that a compact JNL group is profinite and a compact nilpotent JNL group is the additive group of p -adic integers for some prime. Examples show that this fails for compact pronilpotent and solvable groups.

Settore MAT/02 - AlgebraSettore MAT/03 - Geometriacompact Just-Non-Lie groups centerfree compact groups
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