Virtual RTCP: A Case Study of Monitoring and Repair for UDP-based IPTV Systems

IPTV systems have seen widespread deployment, but often lack robust mechanisms for monitoring the quality of experience. This makes it difficult for network operators to ensure that their services match the quality of traditional broadcast TV systems, leading to consumer dissatisfaction. We present a case study of virtual RTCP, a new framework for reception quality monitoring and reporting for UDP-encapsulated MPEG video delivered over IP multicast. We show that this allows incremental deployment of reporting infrastructure, coupled with effective retransmission-based packet loss repair

Efectividad biológica de carbamatos para el control de (Meloidogyne sp.) en tomate y zanahoria en Morelos

El jitomate y la zanahoria son dos hortalizas muy susceptibles a nematodos agalladores como Meloidogyne spp. En zanahoria ocasionan serias reducciones en los rendimientos y pueden incluso llegar a la pérdida total del cultivo, cuando se presenta en zanahoria hay una deformación de las raíces adventicias y por tanto una deformación en la raíz principal, esto hace que se pierda la presentación y calidad de fruto. En tomate el comportamiento es similar, con la formación de agallas en las raíces impidiendo una buen absorción de agua y nutrientes. En este experimento se evaluaron dos productos del grupo químico de los carbamatos, más utilizados para el control de nematodo agallador para visualizar posibles efectos de resistencia a este grupo químico. Los resultados en zanahoria muestran que carbofuran en dosis de 2500 g. ha-1 es quien mejor eficacia tiene para el control de Meloidogyne, mientras que la dosis baja es la que menos control tiene. En el caso del tomate el Oaxamil en su dosis de 4.7 L.ha-1 es la que mejor controla la población de nematodos agalladores y por lo tanto aumenta el rendimiento en la producción

Adición de aceite de atún en dietas para pollos de engorda

El   objetivo   del   presente   estudio   fue   evaluar   el   comportamiento   productivo,   características fisicoquímicas y sensoriales de la carne de pollo de engorde, alimentados con la inclusión de aceite de atún en la dieta. Los tratamientos fueron; T1: dieta testigo, T2: 2.5 % de aceite de atún y T3: 3.5 % de aceite de atún. Se utilizaron 90 pollos de la línea Roos, distribuidos en un diseño completamente al azar, con 30 repeticiones cada tratamiento, las variables evaluadas en comportamiento productivo en las etapas de iniciación y finalización fueron; consumo de alimento, ganancia de peso, conversión alimenticia; respecto a características de la carne fueron: pH, rendimiento de la canal, capacidad de retención de agua y análisis sensorial. Los resultados mostraron diferencias (p<0.05) únicamente en ganancia de peso durante la etapa de finalización y sensorial de la carne. Se concluye que el 2.5% de inclusión de aceite de atún mejoró la ganancia de peso y sensorial de la carne, sin afectar las características fisicoquímicas y rendimiento de la carne

Rare three-body decay t -> c h gamma in the standard model and the two-Higgs doublet model

A complete calculation of the rare three-body decay t --> c h gamma is presented in the framework of the standard model. In the unitary gauge, such a calculation involves about 20 Feynman diagrams. We also calculate this decay in the general two-Higgs doublet model (model III), in which it arises at the tree-level. While in the standard model the decay t --> c h gamma is extremely suppressed, with a branching fraction of the order of $10^{-15}$ for a Higgs boson mass of the order of 115 GeV, in the model III it may have a branching ratio up to $10^{-5}$. We also discuss the crossed decay h --> b \bar{s} gamma.Comment: Updated to match published versio

Search for squarks and gluinos in events with isolated leptons, jets and missing transverse momentum at s√=8 TeV with the ATLAS detector

The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. The search is based on proton-proton collision data at a centre-of-mass energy s√=8 TeV collected in 2012, corresponding to an integrated luminosity of 20 fb−1. No significant excess above the Standard Model expectation is observed. Limits are set on supersymmetric particle masses for various supersymmetric models. Depending on the model, the search excludes gluino masses up to 1.32 TeV and squark masses up to 840 GeV. Limits are also set on the parameters of a minimal universal extra dimension model, excluding a compactification radius of 1/R c = 950 GeV for a cut-off scale times radius (ΛR c) of approximately 30

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector

Results of a search for H → τ τ decays are presented, based on the full set of proton-proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data correspond to integrated luminosities of 4.5 fb−1 and 20.3 fb−1 at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV respectively. All combinations of leptonic (τ → `νν¯ with ` = e, µ) and hadronic (τ → hadrons ν) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standard deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalised to the Standard Model expectation, of µ = 1.43 +0.43 −0.37 is consistent with the predicted Yukawa coupling strength in the Standard Model

Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at s√=8 TeV with ATLAS

Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of s√=8 TeV. The analysis is performed in the H → γγ decay channel using 20.3 fb−1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp → H → γγ fiducial cross section is measured to be 43.2 ±9.4(stat.) − 2.9 + 3.2 (syst.) ±1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured

Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry