Search results for "Planar"

showing 10 items of 412 documents

On the number of limit cycles which appear by perturbation of separatrix loop of planar vector fields

1986

Consider a fami ly of vector fCelds x~ on the plane. This fami ly depends on a parameter ~ ~ /R A, for some A ~ /~, and is supposed to be 0 ~ in (m,~) 6 /i~ 2X /~A. Suppose that for ~ = O, the vector f i e l d X o has a separatrix loop. This means that X o has an hyperbol ic saddle point s o and that one of the stable separatr ix of 8 o coincides with one of the unstable one. The union of th is curve and s o is the loop ?. A return map is defined on one side of r .

SeparatrixGeneral MathematicsSaddle pointMathematical analysisPerturbation (astronomy)Planar vector fieldsAtomic physicsMathematicsBoletim da Sociedade Brasileira de Matemática
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On Automaton Recognizability of Abnormal Extremals

2002

For a generic single-input planar control system $\dot x=F(x)+ u G(x),$ $x\in\mathbb{R}^2,$ $u\in [-1,1]$, $F(0)=0$, we analyze the properties of abnormal extremals for the minimum time stabilization to the origin. We prove that abnormal extremals are finite concatenations of bang arcs with switchings occurring on the set in which the vector fields F and G are collinear. Moreover, all the generic singularities of one parametric family of extremal trajectories near to abnormal extremals are studied. In particular, we prove that all possible sequences of these singularities, and hence all generic abnormal extremals, can be classified by a set of words recognizable by an automaton.

Set (abstract data type)Discrete mathematicsControl and OptimizationPlanarApplied MathematicsControl systemVector fieldGravitational singularityParametric familyOptimal controlAutomatonMathematicsSIAM Journal on Control and Optimization
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Which measures are projections of purely unrectifiable one-dimensional Hausdorff measures

2008

We give a necessary and sufficient condition for a measure p, on the real line to be an orthogonal projection of XAl for some purely 1-unrectifiable planar set A.

Set (abstract data type)PlanarApplied MathematicsGeneral MathematicsOrthographic projectionMathematical analysisHausdorff spaceMathematics::Metric GeometryOuter measureHausdorff measureReal lineMeasure (mathematics)MathematicsProceedings of the American Mathematical Society
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MIXING TIME IN UNBAFFLED STIRRED TANKS

2012

Unbaffled stirred tanks, despite their poorer mixing performance with respect to baffled vessels, are gaining a growing industrial interest as they provide significant advantages in selected applications, including a number of biochemical, food and pharmaceutical processes. There still is however a general lack of information on their mixing performance, that needs to be addressed in order to fully exploit their application potential. The present work is aimed at providing experimental information on mixing rates in an unbaffled vessel operated without top-cover (Uncovered Unbaffled Stirred Tank, UUST). The planar laser induced fluorescence (PLIF) technique was adopted for measuring the dis…

Settore ING-IND/25 - Impianti ChimiciMixing time unbaffled stirred tanks planar laser induced fluorescence PLIF
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Investigation of PCB-based Inductive Sensors Orientation for Corona Partial Discharge Detection

2022

This paper presents an experimental investigation of two different printed circuit board (PCB) inductive sensors, with meander and non-spiral shapes, to assess their capabilities and best orientation for corona partial discharge (PD) detection. First, simulations with the Ansys HFSS software are performed in order to evaluate the equivalent electrical circuit of the two sensors and their 2d radiation patterns. The meander sensors presented a resonant frequency of 600 MHz, while it was around 1.1 GHz for the non-spiral. The 2d radiation pattern showed that better sensitivity is achieved when the inductive sensor is oriented 90 degrees with respect to the PD source. Experimental tests showed …

Settore ING-IND/31 - ElettrotecnicaInductive looppartial discharge detectionplanar inductorsPCB-based sensorInductive loop; PCB-based sensor; Planar inductors; Partial discharge detection
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Sign-preserving solutions for a class of asymptotically linear systems of second-order ordinary differential equations

2022

We study multiplicity of solutions to an asymptotically linear Dirichlet problem associated with a planar system of second order ordinary differential equations. The existence of two sign-preserving component-wise solutions is guaranteed when the Morse indexes of the linearizations at zero and at infinity do not coincide, and one of the asymptotic problems has zero-index. The proof is developed in the framework of topological and shooting methods and it is based on a detailed analysis and characterization of the phase angles in a two-dimensional setting.

Settore MAT/05 - Analisi MatematicaApplied MathematicsAnalysisAsymptotically Linear Planar Systems Sign-preserving Solutions Morse Index Phase Angles
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"Table 126" of "Studies of QCD at e+ e- centre-of-mass energies between 91-GeV and 209-GeV."

2004

Planarity distribution at c.m. energy 133.00 GeV.

Single Differential Cross Section133.0Astrophysics::High Energy Astrophysical PhenomenaE+ E- --> HADRONSE+ E- ScatteringExclusiveHigh Energy Physics::ExperimentComputer Science::Computational GeometryNuclear ExperimentDSIG/DPLANARITY
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"Table 119" of "Studies of QCD at e+ e- centre-of-mass energies between 91-GeV and 209-GeV."

2004

Aplanarity distribution at c.m. energy 133.00 GeV.

Single Differential Cross Section133.0Astrophysics::High Energy Astrophysical PhenomenaE+ E- --> HADRONSE+ E- ScatteringExclusiveHigh Energy Physics::ExperimentDSIG/DAPLANARITYNuclear Experiment
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"Table 130" of "Studies of QCD at e+ e- centre-of-mass energies between 91-GeV and 209-GeV."

2004

Planarity distribution at c.m. energy 189.00 GeV.

Single Differential Cross Section189.0Astrophysics::High Energy Astrophysical PhenomenaE+ E- --> HADRONSE+ E- ScatteringExclusiveHigh Energy Physics::ExperimentComputer Science::Computational GeometryNuclear ExperimentDSIG/DPLANARITY
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"Table 123" of "Studies of QCD at e+ e- centre-of-mass energies between 91-GeV and 209-GeV."

2004

Aplanarity distribution at c.m. energy 189.00 GeV.

Single Differential Cross Section189.0Astrophysics::High Energy Astrophysical PhenomenaE+ E- --> HADRONSE+ E- ScatteringExclusiveHigh Energy Physics::ExperimentDSIG/DAPLANARITYNuclear Experiment
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