EVALUACIÓN DE LA UNIFORMIDAD DE DISTRIBUCIÓN EN CAMPO EN RIEGO POR GOTEO CON AGUAS REGENERADAS: COMPARACIÓN Y PROPUESTA DE UN NUEVO MÉTODO

[EN] Flow distribution uniformity is a parameter used for micro-irrigation evaluation. Different methods describe how to collect data and to calculate the distribution uniformity, such as the procedures developed by Merriam and Keller (1978), ASAE (1998) and Burt (2004). The main difference between these methods is the number and location of the drip emitters used for calculating the distribution uniformity. Nowadays, with increasing use of precision technologies, an alternative method is proposed to estimate distribution uniformity in real time and without using the manpower required by this time-consuming task. This method consists in using flow and pressure data collected by the devices installed in the drip irrigation unit. The proposed procedure will also allow to evaluate subsurface drip irrigation systems, which distribution uniformity otherwise would be very difficult to determine frequently. The evolution of the results obtained by the proposed method according to the irrigation time is more similar with that obtained by Burt’s (2004) method than that obtained following Merriam and Keller’s (1978) method.[ES] La uniformidad de distribución de caudales es una medida de evaluación de los sistemas de riego por goteo. Existen distintos métodos de evaluación de campo descritos para su determinación, entre los cuales destacan los de Merriam y Keller (1978), ASAE (1998) y Burt (2004). La principal diferencia entre estos métodos está en la localización y cantidad de emisores que se utilizan para el cálculo de la uniformidad. En la situación actual de aumento de la utilización de tecnologías de precisión, se propone una alternativa a los métodos existentes consistente en la utilización de registros de caudal y presión proporcionados por distintos medidores instalados en la subunidad de riego, permitiendo estimar la uniformidad de distribución de caudales en tiempo real y sin necesidad de utilización de mano de obra para esta laboriosa tarea. La nueva metodología permitiría, además, evaluar instalaciones de goteo enterrado que de otra manera sería complicado de medir frecuentemente. La evolución de los resultados obtenidos en función de las horas de riego con el método presentado es más parecida a la que se consigue con el método de Burt (2004) que a la obtenida con el método de Merriam y Keller (1978).Duran-Ros, M.; Arbat, G.; Pujol, J.; Barragán, J.; Ramírez De Cartagena, F.; Puig-Bargués, J. (2015). EVALUACIÓN DE LA UNIFORMIDAD DE DISTRIBUCIÓN EN CAMPO EN RIEGO POR GOTEO CON AGUAS REGENERADAS: COMPARACIÓN Y PROPUESTA DE UN NUEVO MÉTODO. En XXXIII CONGRESO NACIONAL DE RIEGOS. Valencia 16-18 junio de 2015. Editorial Universitat Politècnica de València. https://doi.org/10.4995/CNRiegos.2015.1526OC

Diseño de una nueva crepina para reducir la caida de presión en filtros de arena

La filtración es necesaria para evitar la obturación de los emisores, que es el principal problema del riego por goteo. Sin embargo, los filtros necesitan presiones elevadas que están relacionadas con un mayor consumo energético. Estudios anteriores han mostrado que la caída de presión en los filtros de arena, considerados como los estándares en riego por goteo, se localiza principalmente en el drenaje. El principal objetivo del trabajo fue diseñar un nuevo modelo de crepina que redujera la caída de presión en el filtro. Esta nueva crepina tiene mayores pasajes a la salida del drenaje, está rodeada con un medio granular de mayor conductividad hidráulica y modifica la curvatura del flujo por encima de la crepina. La nueva crepina fue construida y ensayada en condiciones de filtrado y contralavado, con y sin medio filtrante, en un filtro de laboratorio escalado a partir de un filtro comercial. Esta nueva crepina redujo considerablemente la caída de presión con respecto el diseño comercial. Se desarrolló también un modelo CFD para analizar con detalle las zonas donde se consigue la reducción observada.Filtration is mandatory for preventing emitter clogging, which is the main drawback of microirrigation. However, microirrigation filters have high pressure requirements, which in turn are related to higher energy consumption. Previous studies have shown that pressure loss in sand media filters, which are usually considered the standard for microirrigation, are mainly located in the filter underdrain. The main objective was to design a new underdrain that could reduce sand media filter pressure drop. The new underdrain has wider passages to the underdrain outlet, is surrounded with a granular medium with higher hydraulic conductivity and it modifies the flow curvature above the underdrain. The new underdrain was built and tested under filtration and backwashing conditions and with and without filter bed using a laboratory filter which was scaled from a commercial filter. The new underdrain considerably reduced pressure loss compared with a commercial filter. A CFD model was developed for further study those filter areas where the underdrain achieved a higher reduction of pressure drop

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

Standalone vertex finding in the ATLAS muon spectrometer

A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson

Measurement of the top quark pair cross section with ATLAS in pp collisions at √s=7 TeV using final states with an electron or a muon and a hadronically decaying τ lepton

A measurement of the cross section of top quark pair production in proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 7 TeV is reported. The data sample used corresponds to an integrated luminosity of 2.05 fb -1. Events with an isolated electron or muon and a τ lepton decaying hadronically are used. In addition, a large missing transverse momentum and two or more energetic jets are required. At least one of the jets must be identified as originating from a b quark. The measured cross section, σtt-=186±13(stat.)±20(syst.)±7(lumi.) pb, is in good agreement with the Standard Model prediction

Measurement of the top quark-pair production cross section with ATLAS in pp collisions at \sqrt{s}=7\TeV

A measurement of the production cross-section for top quark pairs(\ttbar) in $pp$ collisions at \sqrt{s}=7 \TeV is presented using data recorded with the ATLAS detector at the Large Hadron Collider. Events are selected in two different topologies: single lepton (electron $e$ or muon $\mu$) with large missing transverse energy and at least four jets, and dilepton ($ee$, $\mu\mu$ or $e\mu$) with large missing transverse energy and at least two jets. In a data sample of 2.9 pb-1, 37 candidate events are observed in the single-lepton topology and 9 events in the dilepton topology. The corresponding expected backgrounds from non-\ttbar Standard Model processes are estimated using data-driven methods and determined to be $12.2 \pm 3.9$ events and $2.5 \pm 0.6$ events, respectively. The kinematic properties of the selected events are consistent with SM \ttbar production. The inclusive top quark pair production cross-section is measured to be \sigmattbar=145 \pm 31 ^{+42}_{-27} pb where the first uncertainty is statistical and the second systematic. The measurement agrees with perturbative QCD calculations.Comment: 30 pages plus author list (50 pages total), 9 figures, 11 tables, CERN-PH number and final journal adde

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

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