Search results for "variant"

showing 10 items of 1267 documents

Conjugate unstable manifolds and their underlying geometrized Markov partitions

2000

Abstract Conjugate unstable manifolds of saturated hyperbolic sets of Smale diffeomorphisms are characterized in terms of the combinatorics of their geometrized Markov partitions. As a consequence, the relationship between the local and the global point of view is also made explicit.

Discrete mathematicsSmale diffeomorphismsMathematics::Dynamical SystemsMarkov chainInvariant manifoldsGeometrized Markov partitionsPoint (geometry)Geometry and TopologyMathematics::Symplectic GeometryMathematics::Geometric TopologyConjugateMathematicsTopology and its Applications
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Discrete Derivatives for Atom-Pairs as a Novel Graph-Theoretical Invariant for Generating New Molecular Descriptors: Orthogonality, Interpretation an…

2013

This report presents a new mathematical method based on the concept of the derivative of a molecular graph (G) with respect to a given event (S) to codify chemical structure information. The derivate over each pair of atoms in the molecule is defined as ∂G/∂S(vi  , vj )=(fi -2fij +fj )/fij , where fi (or fj ) and fij are the individual frequency of atom i (or j) and the reciprocal frequency of the atoms i and j, respectively. These frequencies characterize the participation intensity of atom pairs in S. Here, the event space is composed of molecular sub-graphs which participate in the formation of the G skeleton that could be complete (representing all possible connected sub-graphs) or comp…

Discrete mathematicsSteric effectsQuantitative structure–activity relationshipOrganic ChemistryComputer Science Applicationschemistry.chemical_compoundchemistryStructural BiologyComputational chemistryMolecular descriptorDrug DiscoveryPrincipal component analysisMolecular MedicineMolecular graphLinear independenceInvariant (mathematics)Linear combinationMolecular informatics
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Periodic and quasi-periodic orbits of the dissipative standard map

2011

We present analytical and numerical investigations of the dynamics of the dissipative standard map. We first study the existence of periodic orbits by using a constructive version of the implicit function theorem; then, we introduce a parametric representation, which provides the interval of the drift parameter ensuring the existence of a periodic orbit with a given period. The determination of quasi--periodic attractors is efficiently obtained using the parametric representation combined with a Newton's procedure, aimed to reduce the error of the approximate solution provided by the parametric representation. These methods allow us to relate the drift parameter of the periodic orbits to th…

Dissipative standard mapApplied MathematicsMathematical analysisArnold's tonguesPeriodic sequenceStandard mapParameter spaceImplicit function theoremAttractorDissipative systemDiscrete Mathematics and CombinatoricsPeriodic orbitsArnold's tongues; Dissipative standard map; Periodic orbits; Discrete Mathematics and Combinatorics; Applied MathematicsInvariant (mathematics)Dissipative standard map; Periodic orbits; Arnold's tonguesSettore MAT/07 - Fisica MatematicaParametric statisticsMathematics
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Control of Production-Distribution Systems under Discrete Disturbances and Control Actions

2011

This paper deals with the robust control and optimization of production-distribution systems. The model used in our problem formulation is a general network flow model that describes production, logistics, and transportation applications. The novelty in our formulation is in the discrete nature of the control and disturbance inputs. We highlight three main contributions: First, we derive a necessary and sufficient condition for the existence of robustly control invariant hyperboxes. Second, we show that a stricter version of the same condition is sufficient for global convergence to an invariant set. Third, for the scalar case, we show that these results parallel existing results in the set…

Distribution systemMathematical optimizationSettore ING-INF/04 - AutomaticaControl theoryNoveltyHypercubealphapet control production-distribution systemsInvariant (physics)Robust controlSettore MAT/09 - Ricerca OperativaFlow networkMathematics
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An overview of statin-induced myopathy and perspectives for the future

2020

Introduction: Statins remain the most commonly prescribed lipid-lowering drug class for the treatment of atherosclerotic cardiovascular disease. Their well-recognized side effects are known as statin-associated muscle symptom (SAMS). Some advances in this field have been made in recent years, but the understanding of the mechanisms has lagged. Investigating the specific role of the anti-HMGCR autoantibody, pharmacokinetic genetic variants, characterization of the known phenotypes of statin toxicity, in relation to clinical markers of disease, is of high importance. Areas covered: We summarized currently available findings (on PubMed) related to SAMS and discussed the therapeutic approaches,…

DrugStatinUbiquinonemedicine.drug_classmedia_common.quotation_subjectHyperlipidemiasDiseasetherapeutic approaches030204 cardiovascular system & hematologyBioinformaticsPharmacogenomic Variants03 medical and health sciences0302 clinical medicineMuscular DiseasesRisk FactorsmedicineAnimalsHumansDrug InteractionsPharmacology (medical)Adverse effectHypolipidemic Agentsmedia_commondrug interactionbusiness.industryGeneral MedicineAtherosclerosisStatin induced myopathystatin-induced myopathyunderlying mechanismDrug classrisk factor030220 oncology & carcinogenesisCoenzyme Q10Hydroxymethylglutaryl-CoA Reductase Inhibitorsmyositis autoantibodieRisk assessmentbusinessstatin-associated muscle symptom
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Detecting tri‐stability of 3D models with complex attractors via meshfree reconstruction of invariant manifolds of saddle points

2018

In mathematical modeling it is often required the analysis of the vector field topology in order to predict the evolution of the variables involved. When a dynamical system is multi-stable the trajectories approach different stable states, depending on the initialmconditions. The aim of this work is the detection of the invariant manifolds of thesaddle points to analyze the boundaries of the basins of attraction. Once that a sufficient number of separatrix points is found a Moving Least Squares meshfree method is involved to reconstruct the separatrix manifolds. Numerical results are presented to assess the method referring to tri-stable models with complex attractors such as limit cycles o…

Dynamical systems Invariant manifolds Separatrix Meshfree method Moving Least Squares.Dynamical systems theorySeparatrixGeneral MathematicsMathematical analysisGeneral Engineering3d model010103 numerical & computational mathematics01 natural sciences010101 applied mathematicsSettore MAT/08 - Analisi NumericaSaddle pointAttractor0101 mathematicsMoving least squaresInvariant (mathematics)MathematicsMathematical Methods in the Applied Sciences
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"Table 3" of "Production of Lambda, Cascade and Omega Hyperons in ppbar Collisions at1.96 TeV Center of Mass Energy"

2011

The PT differential cross section for OMEGA- production in the |pseudorapidity| range < 1.

E*D3SIG/DP**32047761Inclusive2047761NPBAR P --> OMEGA- X1960.0PBAR P --> OMEGABAR+ XInvariant Cross Section
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"Table 2" of "Production of Lambda, Cascade and Omega Hyperons in ppbar Collisions at1.96 TeV Center of Mass Energy"

2011

The PT differential cross section for XI- production in the |pseudorapidity| range < 1.

E*D3SIG/DP**32047761InclusivePBAR P --> XIBAR+ X2047761NPBAR P --> XI- X1960.0Invariant Cross Section
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"Table 5" of "Production of Lambda, Cascade and Omega Hyperons in ppbar Collisions at1.96 TeV Center of Mass Energy"

2011

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E*D3SIG/DP**32047761InclusivePBAR P --> XIBAR+ X2047761NPBAR P --> XI- X1960.0Invariant Cross Section
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"Table 1" of "Neutral pion and $\eta$ meson production in proton-proton collisions at $\sqrt{s}=0.9$ TeV and $\sqrt{s}=7$ TeV"

2012

The measured invariant differential section for inclusive PI0 production at a centre-of-mass energy of 7 TeV.

E*D3SIG/DP**3InclusiveP P --> PI0 XProton-Proton ScatteringAstrophysics::High Energy Astrophysical Phenomena7000.0High Energy Physics::ExperimentNuclear ExperimentInvariant Cross Section
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