Search results for " Matrix"

showing 10 items of 2053 documents

The mapping properties of the radiosity operator along an edge

2002

In this article we study the radiosity operator along an edge between two adjacent half-planes. First we show that the radiosity operator is invertible in a whole scale of anisotropic Sobolev spaces. In the absence of any shadows we are able to derive regularity properties of the solution, which depend only on the angle between the half-planes, the reflectivity coefficients and the right-hand side. This work can be considered as a supplement to the article of Rathsfeld (Mathematical Methods in the Applied Sciences 1999; 22: 217–241). Copyright © 2002 John Wiley & Sons, Ltd.

Scale (ratio)General MathematicsMathematical analysisGeneral EngineeringRadiosity (computer graphics)Edge (geometry)Integral equationlaw.inventionSobolev spaceOperator (computer programming)Invertible matrixlawAnisotropyMathematicsMathematical Methods in the Applied Sciences
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A Mlp-Based Digit And Uppercase Characters Recognition System

1997

A simple software solution for digit and uppercase handwritten characters recognition is presented. The proposed solution is based on a two-layer Multi Layer Perceptron (MLP) trained by a conjugate gradient descent (CGD) optimization algorithm. This neural network is embedded in a software tool for automatic processing of forms achieved using a scanner. The chosen solutions allow us to obtain good results both in terms of recognition rate and speed. In the paper are fully described design details and experimental results.

ScannerArtificial neural networkComputer sciencebusiness.industrySpeech recognitionNumerical digitComputingMethodologies_PATTERNRECOGNITIONSoftwareSimple (abstract algebra)Computer Science::Computer Vision and Pattern RecognitionMultilayer perceptronConjugate gradient methodLogical matrixbusiness
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Properties of a matrix group associated to a {K,s+1}-potent matrix

2012

In a previous paper, the authors introduced and characterized a new kind of matrices called {K,s+1}-potent. In this paper, an associated group to a {K, s+1}-potent matrix is explicitly constructed and its properties are studied. Moreover, it is shown that the group is a semidirect product of Z_2 acting on Z_{(s+1)^2-1}. For some values of s, more specifications on the group are derived. In addition, some illustrative examples are given.

Semidirect productAlgebra and Number TheoryGroup (mathematics)Involutory matrixMatrius (Matemàtica)CombinatoricsAlgebraMatrix (mathematics)Matrix groupGroupInvolutory matrixÀlgebra linealMATEMATICA APLICADAMathematics{K s + 1}-potent matrix
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Measurement of theB0→π−ℓ+νandB+→η(′)ℓ+νbranching fractions, theB0→π−ℓ+νandB+→ηℓ+νform-factor shapes, and determination of|Vub|

2011

We report the results of a study of the exclusive charmless semileptonic decays, B^+ → η^((′))l^+ν and B^0 → π^-l^+ν, undertaken with approximately 464 × 10^6 BB pairs collected at the Υ(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with a loose neutrino reconstruction technique. We obtain partial branching fractions for B^+ → ηl^+ν and B^0 → π^-l^+ν decays in three and 12 bins of q^2, respectively, from which we extract the f_+(q^2) form-factor shapes and the total branching fractions B(B^+ → ηl^+ν)=(0.36 ± 0.05_(stat) ± 0.04_(syst))× 10^(-4) and B(B^0 → π^-l^+ν)=(1.42 ± 0.05_(stat) ± 0.07_(syst)) × 10^(-4). We also measure B…

Semileptonic decayPhysicsNuclear and High Energy Physics010308 nuclear & particles physicsCabibbo–Kobayashi–Maskawa matrixBranching fractionElectron–positron annihilationAnalytical chemistryForm factor (quantum field theory)01 natural sciencesNuclear physicsParticle decay0103 physical sciences010306 general physicsLeptonDimensionless quantityPhysical Review D
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Properties of hyperons in chiral perturbation theory

2009

The development of chiral perturbation theory in hyperon phenomenology has been troubled due to power-counting subtleties and to a possible slow convergence. Furthermore, the presence of baryon-resonances, e.g. the lowest-lying decuplet, complicates the approach, and the inclusion of their effects may become necessary. Recently, we have shown that a fairly good convergence is possible using a renormalization prescription of the loop-divergencies which recovers the power counting, is covariant and consistent with analyticity. Moreover, we have systematically incorporated the decuplet resonances taking care of both power-counting and $consistency$ problems. A model-independent understanding o…

Semileptonic decayPhysicsNuclear and High Energy PhysicsParticle physicsChiral perturbation theoryMagnetic momentCabibbo–Kobayashi–Maskawa matrixNuclear TheoryHigh Energy Physics::PhenomenologyHyperonFOS: Physical sciencesFísicaHyperon phenomenologyRenormalizationHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Chiral perturbation theoryCovariant transformationHigh Energy Physics::ExperimentPhenomenology (particle physics)
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Study ofB¯→Xuℓν¯decays inBB¯events tagged by a fully reconstructedB-meson decay and determination of|Vub|

2012

We report measurements of partial branching fractions for inclusive charmless semileptonic B decays Bbar --> Xu l nubar, and the determination of the CKM matrix element |V_{ub}|. The analysis is based on a sample of 467 million Upsilon(4S) --> BBar decays recorded with the BaBar detector at the PEP-II e^+ e^- storage rings. We select events in which the decay of one of the B mesons is fully reconstructed and an electron or a muon signals the semileptonic decay of the other B meson. We measure partial branching fractions DeltaB in several restricted regions of phase space and determine the CKM element |V_{ub}| based on four different QCD predictions. For decays with a charged lepton momentum…

Semileptonic decayPhysicsNuclear and High Energy PhysicsParticle physicsMuon010308 nuclear & particles physicsCabibbo–Kobayashi–Maskawa matrixHigh Energy Physics::PhenomenologyHadron01 natural sciencesNuclear physicsIsospin0103 physical sciencesHigh Energy Physics::ExperimentB mesonInvariant mass010306 general physicsLeptonPhysical Review D
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Study of dynamics ofD0→K−e+νeandD0→π−e+νedecays

2015

In an analysis of a 2.92 fb(-1) data sample taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions B(D-0 -> K(-)e(+)nu(e)) = (3.505 +/- 0.014 +/- 0.033)% and B(D-0 -> pi(-)e(+)nu(e)) = (0.295 +/- 0.004 +/- 0.003)%. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element f(+)(K)(0)vertical bar V-cs vertical bar = 0.7172 +/- 0.0025 +/- 0.0035 and f(+)(pi)(0)vertical bar V-cd vertical bar = 0.1435 +/- 0.0018 +/- 0.0009. Combining these products with the values of vertical bar V-cs(d)vertical bar from the SM constrain…

Semileptonic decayPhysicsNuclear and High Energy PhysicsQCD sum rulesParticle physics010308 nuclear & particles physicsCabibbo–Kobayashi–Maskawa matrixElectron–positron annihilationHadronAnalytical chemistryLattice QCD01 natural sciencesLight cone0103 physical sciencesSum rule in quantum mechanics010306 general physicsPhysical Review D
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Note on the slope parameter of the baryonic Λb→Λc Isgur–Wise function

2005

Abstract Using the framework of the Heavy Quark Effective Theory we have re-analyzed the Isgur–Wise function describing semileptonic Λ b → Λ c decays in the QCD sum rule approach. The slope parameter of the Isgur–Wise function is found to be ρ 2 = 1.35 ± 0.13 , which is consistent with an experimental measurement and a lattice calculation. To O ( 1 / m b , 1 / m c ) of the heavy quark expansion the integrated Λ b decay width is used to extract the CKM matrix element V c b for which we obtain a value of | V c b | = 0.041 ± 0.004 ± 0.001 in excellent agreement with the value of | V c b | determined from semileptonic B → D ∗ decays.

Semileptonic decayQuantum chromodynamicsPhysicsBaryonNuclear and High Energy PhysicsQCD sum rulesParticle physicsCabibbo–Kobayashi–Maskawa matrixB mesonSum rule in quantum mechanicsLambdaPhysics Letters B
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Compromised nuclear envelope integrity drives tumor cell invasion

2020

AbstractWhile mutations leading to a fragile envelope of the cell nucleus are well known to cause diseases such as muscular dystrophies or accelerated aging, the pathophysiological consequences of the recently discovered mechanically induced nuclear envelope ruptures in cells harboring no mutation are less known. Here we show that repeated loss of nuclear envelope integrity in nuclei experiencing mechanical constraints promotes senescence in nontransformed cells, and induces an invasive phenotype including increased collagen degradation in human breast cancer cells, both in vitro and in a mouse xenograft model of breast cancer progression. We show that these phenotypic changes are due to th…

SenescenceCell nucleusMutationmedicine.anatomical_structureCytoplasmChemistryDNA damageCancer cellmedicinemedicine.disease_causePhenotypeExtracellular Matrix DegradationCell biology
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Compromised nuclear envelope integrity drives TREX1-dependent DNA damage and tumor cell invasion

2021

Although mutations leading to a compromised nuclear envelope cause diseases such as muscular dystrophies or accelerated aging, the consequences of mechanically induced nuclear envelope ruptures are less known. Here, we show that nuclear envelope ruptures induce DNA damage that promotes senescence in non-transformed cells and induces an invasive phenotype in human breast cancer cells. We find that the endoplasmic reticulum (ER)-associated exonuclease TREX1 translocates into the nucleus after nuclear envelope rupture and is required to induce DNA damage. Inside the mammary duct, cellular crowding leads to nuclear envelope ruptures that generate TREX1-dependent DNA damage, thereby driving the …

SenescenceExonucleaseDNA damageNuclear Envelope[SDV]Life Sciences [q-bio]Breast NeoplasmsBiologySettore MED/08 - Anatomia PatologicaGeneral Biochemistry Genetics and Molecular BiologyCell LineMicemedicineSettore MED/05 - Patologia ClinicaAnimalsHumansNeoplasm InvasivenessEpithelial–mesenchymal transitionCellular SenescenceEndoplasmic reticulumPhosphoproteinsXenograft Model Antitumor AssaysCell biology[SDV] Life Sciences [q-bio]medicine.anatomical_structureExodeoxyribonucleasesCancer cellProteolysisbiology.proteinTREX1 nuclear envelope rupture DNA damage mammary duct carcinoma tumor invasion senescence breast cancer cGAS confinement epithelial to mesenchymal transition Animals Breast Neoplasms Cell Line Cellular Senescence Collagen Disease Progression Exodeoxyribonucleases Female Humans Mice Neoplasm InvasivenessNuclear Envelope PhosphoproteinsProteolysis Xenograft Model Antitumor Assays DNA DamageDisease ProgressionFemaleCollagenNucleusExtracellular Matrix DegradationDNA Damage
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