Search results for "Geometric analysis"

showing 10 items of 23 documents

Molecular correlation functions for uniaxial ellipsoids in the isotropic state

2006

We perform event-driven molecular dynamics simulations of a system composed by uniaxial hard ellipsoids for different values of the aspect-ratio and packing fraction . We compare the molecular orientational-dependent structure factors previously calculated within the Percus-Yevick approximation with the numerical results. The agreement between theoretical and numerical results is rather satisfactory. We also show that, for specific orientational quantities, the molecular structure factors are sensitive to the particle shape and can be used to distinguish prolate from oblate ellipsoids. A first-order theoretical expansion around the spherical shape and a geometrical analysis of the configura…

Physicshard ellipsoid; isotropic-nematic transition; structureGeometric analysisPHASE-DIAGRAMIsotropyStructure (category theory)General Physics and AstronomyFOS: Physical sciencesState (functional analysis)Condensed Matter - Soft Condensed MatterAtomic packing factorEllipsoidLINEAR-MOLECULESMolecular dynamicsClassical mechanicsNEMATIC TRANSITIONFLUIDSHARD ELLIPSOIDSParticleSoft Condensed Matter (cond-mat.soft)Physical and Theoretical Chemistry
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Assouad Type Dimensions in Geometric Analysis

2021

We consider applications of the dual pair of the (upper) Assouad dimension and the lower (Assouad) dimension in analysis. We relate these notions to other dimensional conditions such as a Hausdorff content density condition and an integrability condition for the distance function. The latter condition leads to a characterization of the Muckenhoupt Ap properties of distance functions in terms of the (upper) Assouad dimension. It is also possible to give natural formulations for the validity of Hardy–Sobolev inequalities using these dual Assouad dimensions, and this helps to understand the previously observed dual nature of certain cases of these inequalities. peerReviewed

osittaisdifferentiaaliyhtälötPure mathematicsLower dimensionGeometric analysisAssouad dimensionAikawa conditionHardy–Sobolev inequalityDimension (graph theory)Hausdorff spaceMuckenhoupt weightCharacterization (mathematics)Type (model theory)Dual (category theory)Content (measure theory)Mathematics::Metric GeometrymittateoriaepäyhtälötMathematicsDual pair
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The tree of life in the southern porch of the cathedral of Palermo: survey and geometric analysis

2016

This study focuses one of the most puzzling works of art made in Palermo at the end of the medieval age: the tree of life, a rich geometrical decoration with animal and human figures in the southern porch of the Cathedral of Palermo. Topographic and SfM photogrammetric methods produced a detailed orthophoto of the porch. Images collected during restoration have been rectified and superimposed to the orthophoto. The geometrical analysis of the decorative patterns reveals a complex design and meaningful links between the decoration and the general architectural layout of the porch.

Settore ICAR/17 - DisegnoMedieval patterns Tree of life Geometric analysis.
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Qualitative Theory of Differential Equations, Difference Equations, and Dynamic Equations on Time Scales

2016

We are pleased to present this special issue. This volume reflects an increasing interest in the analysis of qualitative behavior of solutions to differential equations, difference equations, and dynamic equations on time scales. Numerous applications arising in the engineering and natural sciences call for the development of new efficient methods and for the modification and refinement of known techniques that should be adjusted for the analysis of new classes of problems. The twofold goal of this special issue is to reflect both the state-of-the-art theoretical research and important recent advances in the solution of applied problems.

Mathematical optimizationGeometric analysisDynamical systems theoryArticle SubjectDifferential equationComputer sciencelcsh:Tlcsh:Rlcsh:MedicineGeneral MedicineDelay differential equationlcsh:TechnologyGeneral Biochemistry Genetics and Molecular Biology[0-Belirlenecek]Examples of differential equationsNonlinear systemMultigrid methodEditorialSimultaneous equationsApplied mathematicslcsh:Qlcsh:ScienceGeneral Environmental Science
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A geometric analysis of the effects of noise on Berry phase

2007

In this work we describe the effect of classical and quantum noise on the Berry phase. It is not a topical review article but rather an overview of our work in this field aiming at giving a simple pictorial intuition of our results.

PhysicsWork (thermodynamics)Physics and Astronomy (miscellaneous)Geometric analysisField (physics)General MathematicsQuantum noiseQUANTUM COMPUTATIONNoiseGeometric phaseSYSTEMSSimple (abstract algebra)Quantum error correctionQuantum mechanicsgeometric phases open quantum systems quantum information theoryStatistical physics
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The latent geometry of the human protein interaction network

2017

Abstract Motivation A series of recently introduced algorithms and models advocates for the existence of a hyperbolic geometry underlying the network representation of complex systems. Since the human protein interaction network (hPIN) has a complex architecture, we hypothesized that uncovering its latent geometry could ease challenging problems in systems biology, translating them into measuring distances between proteins. Results We embedded the hPIN to hyperbolic space and found that the inferred coordinates of nodes capture biologically relevant features, like protein age, function and cellular localization. This means that the representation of the hPIN in the two-dimensional hyperboli…

0301 basic medicineStatistics and ProbabilityGeometric analysisComputer scienceHyperbolic geometrySystems biologyComplex systemContext (language use)GeometryBiochemistryProtein–protein interaction03 medical and health sciencesInteraction networkHumansProtein Interaction MapsRepresentation (mathematics)Cluster analysisMolecular BiologySystems BiologyHyperbolic spaceProteinsFunction (mathematics)Original PapersComputer Science ApplicationsComputational Mathematics030104 developmental biologyComputational Theory and MathematicsEmbeddingSignal transductionAlgorithmsSignal Transduction
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Multiresolution Analysis for Meshes with Appearance Attributes

2005

International audience; We present a new multiresolution analysis framework for irregular meshes with attributes based on the lifting scheme. We introduce a surface prediction operator to compute the detail coefficients for the geometry and the attributes of the model. Attribute analysis gives appearance information to complete the geometrical analysis of the model. A set of experimental results are given to show the efficiency of our framework. We present two applications to adaptive visual-ization and denoising.

Surface (mathematics)Lifting schemeGeometric analysisNoise reductionMultiresolution analysis[INFO.INFO-GR] Computer Science [cs]/Graphics [cs.GR]02 engineering and technology[INFO.INFO-CG]Computer Science [cs]/Computational Geometry [cs.CG]01 natural sciences010309 opticsSet (abstract data type)Operator (computer programming)[INFO.INFO-CV] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]0103 physical sciences0202 electrical engineering electronic engineering information engineeringPolygon meshMathematicsComputingMethodologies_COMPUTERGRAPHICSbusiness.industry[INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]020207 software engineeringPattern recognition[INFO.INFO-GR]Computer Science [cs]/Graphics [cs.GR][INFO.INFO-CG] Computer Science [cs]/Computational Geometry [cs.CG]Artificial intelligencebusiness
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Geometric Analysis of Type B Aortic Dissections Shows Aortic Remodeling After Intervention Using Multilayer Stents

2020

Recently, multilayer stents for type B aortic dissections (TBAD) have been proposed to decrease false lumen flow, increase and streamline true lumen flow, and retain branch vessel patency. We aimed to provide a protocol with standardized techniques to investigate aortic remodeling of TBAD by multilayer flow modulators (MFM) in static geometric and hemodynamic analyses. Combining existing literature and new insights, a standardized protocol was designed. Using pre- and postoperative CT scans, geometric models were constructed, lumen dimensions were calculated, computational fluid dynamics (CFD) models were composed, and velocity and pressures were calculated. Sixteen TBAD cases treated with …

Materials scienceGeometric analysisHemodynamics3d modelcomputational fluid dynamics030204 cardiovascular system & hematologylcsh:TechnologyArticle03 medical and health sciences0302 clinical medicinemedicineMedical imagingGeneral Materials Scienceaortic dissectionlcsh:Microscopylcsh:QC120-168.85Aortic dissectionlcsh:QH201-278.5multilayer flow modulatorlcsh:Tmedicine.diseaseaortic remodelinggeometric analysisLumen DiameterFlow velocitylcsh:TA1-2040lcsh:Descriptive and experimental mechanicslcsh:Electrical engineering. Electronics. Nuclear engineeringlcsh:Engineering (General). Civil engineering (General)lcsh:TK1-9971030217 neurology & neurosurgeryBiomedical engineeringLumen (unit)Materials
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U.I.R.D.A. – Unbuilt Italian Rationalism Digital Archive

2018

For twenty years, the architecture of Italian rationalism through the digital modelling has been investigated. Very often, the production of a model and the consequent representation of tridimensional views, in many case studies, as outcome of the research on architecture have been considered. Actually, the digital model, intended as a critical tool, has to be conceived as a ‘starting point' for graphic analysis of architecture and not as the outcome. Indeed, it is associated to other graphics, sometimes not ‘deducted' from the model, useful for the understanding/translation of architecture. The construction of the model is not the construction of a simple image, operation, which is often c…

Engineeringbusiness.industryDiagoneo/i: Harmonic ratio. Rectangle which ratio between the two sides corresponds to the ratio between the side of a square and its diagonal. Diapente: Harmonic ratio. Rectangle with sides in ratio 2:3. Diatessaron: Harmonic ratio. Rectangle with sides in ratio 3:4. Digital Archive: Cataloging of drawings obtained through the implementation of digital modeling software within a database that collects graphic elaborations acquired from archive drawings. Golden Ratio: Indicates the ratio between the two dimensions of which the major is the mean proportional between the minor and the sum of the two. Graphic Reading: Reading and understanding operation of an architecture through its decomposition into volumetric and geometric parts graphically expressed through an additional language. Harmonic Ratios: Geometric ratios between pure shapes traceable also in music that enable us to understand the spatial logic of drawn architecture. Hermeneutic Analysis: Interpretive approach adopted in the graphic analysis of an architecture drawing leading to the seeking of further key interpretations of the work itself. Redrawing: Graphic restitution of one or more archive drawings obtained by an interpretative practice of the project and expressed through the codes of representation that provide new information on architecture. Volumetric Analysis: Graphic analysis related to spatial logics that exist between the tridimensional elements of architecture read through schemes orthogonal projections and geometric analysis.Settore ICAR/17 - DisegnobusinessClassicsRationalism (international relations)
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Dal rilievo alla ricostruzione del progetto: la torre Pisana nel Palazzo Reale di Palermo

2017

The paper focuses the survey and representation of the Pisana Tower in the Royal Palace of Palermo. The tower, which has recently been inserted in the UNESCO World Heritage List, was built in the XII century under the patronage of Norman kings. Along the centuries, the tower has undergone several transformations, to fit ever-changing uses. The coexistence of such heterogeneous elements, combined with the fragmentation of the passages connecting the levels of the tower, conceal the original unity and the typology of this historical building. Researches focusing the study of monuments deeply transformed along their history, even when based on the cooperation of multidisciplinary scholarships,…

Royal Palace of Palermo Torre Pisana Reconstruction Geometric analysisSettore ICAR/17 - Disegno
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