2,546 research outputs found
Development of the ATLAS High-Level Trigger Steering and Inclusive Searches for Supersymmetry
The presented thesis is divided into two distinct parts. The subject of the first part is the ATLAS high-level trigger (HLT), in particular the development of the HLT Steering, and the trigger user-interface. The second part presents a study of inclusive supersymmetry searches, including a novel background estimation method for the relevant Standard Model (SM) processes. The trigger system of the ATLAS experiment at the Large Hadron Collider (LHC) performs the on-line physics selection in three stages: level-1 (LVL1), level-2 (LVL2), and the event filter (EF). LVL2 and EF together form the HLT. The HLT receives events containing detector data from high-energy proton (or heavy ion) collisions, which pass the LVL1 selection at a maximum rate of 75 kHz. It must reduce this rate to ~200 Hz, while retaining the most interesting physics. The HLT is a software trigger and runs on a large computing farm. At the heart of the HLT is the Steering software. The HLT Steering must reach a decision whether or not to accept an event within a time budget of less than 40 ms (LVL2) and under 4 s (EF), averaged over all events. Its decision is based on the results of customised trigger algorithms. These algorithms perform a specific data reconstruction task in a small geometrical detector region. The Steering controls the flow and execution of these algorithms, such that only interesting (typically high-pT) detector regions are exami ned in several steps. The principles and design of this HLT selection strategy are discussed in detail. The final implementation of the Steering, including all required features such as pre-scaling, is presented. Furthermore, commissioning results from technical and cosmic ray runs are described. Finally, the common interface to all trigger results for off-line analysis and debugging is presented. Supersymmetry (SUSY) is a theoretically attractive scenario for physics beyond the SM which may also provide a suitable dark matter candidate in models where R-parity (+1 for SM and -1 for SUSY particles) is conserved. If SUSY is realised at a mass scale of ~1 TeV, as favoured by several arguments, it will be accessible at the LHC at CERN within the first years of data-taking. The second part of this thesis presents the inclusive one-lepton search strategy for generic SUSY models with R-parity conservation with the ATLAS detector at the LHC. The signature of this search mode is based on large missing transverse momentum from undetected neutralinos, multiple high-pT jets and one lepton. The corresponding discovery reach is shown for the first fb^-1 of ATLAS data. Furthermore, background estimation techniques for inclusive SUSY searches are discussed. A novel background determination approach, denoted the Tiles Method, is proposed, which translates prior knowledge on the SM distributions of discriminating variables in a two or hi gher dimensional grid into an estimate of the abundances of SM and beyond-SM events. Depending on the grid granularity, the abundances are calculated by solving a system of linear equations or by minimising a log-likelihood function. The method does not rely on assumptions on background dominance for particular values of the variables, nor does it require iterations. Systematic effects due to uncertainties in the simulated prior distributions are investigated. Results for various mSUGRA scenarios are presented
Qualidade de cocção de grĂŁos de arroz translĂșcidos e gessados.
objetivou-se avaliar o comportamento de cocção dos grĂŁos de arroz translĂșcidos e gessados e seus aspectos de qualidade
Liquid-injection atomic layer deposition of TiOx and Pb-Ti-O films
Pb-Ti-O films were prepared by liquid-injection atomic layer deposition (ALD) using H2O as oxygen source after evaluating Ti precursors with different beta-diketonate type ligands, Ti(OC3H7)(2)(C11H19O2)(2) [Ti(Oi-Pr)(2)(DPM)(2)] and Ti(OC5H11)(2)(C10H17O2)(2) [Ti(Ot-Am)(2)(IBPM)(2)], dissolved in ethylcyclohexane. For both Ti precursors, the apparent thermal activation energy of the deposition rate of TiOx films increased at a deposition temperature of about 380 degrees C, and the deposition rate of TiOx films grown at 300 degrees C saturated against the volume of injected Ti precursors. Ti(Oi-Pr)(2)(DPM)(2) was selected for the subsequent Pb-Ti-O film deposition because of its high precursor efficiency and the low temperature dependence of the deposition rate. Pb-Ti-O films were prepared using Ti(Oi-Pr)(2)(DPM)(2) and Pb(C12H21O2)(2) [Pb(TMOD)(2)] at deposition temperatures of 240 and 300 degrees C. The deposition rates of Pb and Ti in the Pb-Ti-O process were higher than those in binary PbO and TiOx processes under the same deposition conditions. The deposition rate of Pb in the Pb-Ti-O process showed a linear increase in response to the injected Pb precursor volume, which was different from the saturated deposition rate of the PbO process. The interface chemistry between the precursors and predeposited cation layers has critical impact on the self-regulated growth mechanism in the multicomponent oxide ALD. (c) 2006 The Electrochemical Society
CaracterĂsticas fĂsicas dos grĂŁos de arroz translĂșcidos e gessados.
Objetivou-se neste trabalho avaliar as caracterĂsticas de transparĂȘncia, brancura e grau de polimento dos grĂŁos de arroz translĂșcidos e gessados
Efeito da percentagem de grĂŁos gessados sobre a viscosidade do arroz.
O objetivo deste trabalho foi avaliar a viscosidade do arroz com diferentes porcentagens de grĂŁos gessados, sob efeito da temperatura e tempo
Qualidade industrial dos grĂŁos de arroz de populaçÔes promissoras quanto Ă resistĂȘncia ao estresse hĂdrico, cultivadas em Ă©pocas distintas.
O objetivo deste estudo, que ainda estĂĄ em fase de avaliação, foi de avaliar se hĂĄ diferença na renda e rendimento de inteiros de uma população de arroz de terras altas, selecionada por conter materiais genĂ©ticos promissores quanto Ă produção em perĂodos secos ou com ĂĄgua limitante
Cobalt-based Nanoreactors in Combined Fischer-Tropsch Synthesis and Hydroprocessing: Effects on Methane and CO Selectivity
Fischer-Tropsch synthesis: Four types of bi-functional catalysts with cobalt nanoparticles supported on meso- or microporous silicates or aluminosilicates are investigated regarding the obtained CO and CH selectivity under low-temperature Fischer-Tropsch reaction conditions. In situ x-ray absorption spectroscopy results under industrially relevant conditions reveal that strong cobalt-support interactions and oxidized cobalt species are the main factors determining the selectivity depending on the specific support material used.
The production of liquid hydrocarbons from syngas (CO and H) via the combined Fischer-Tropsch (FT) synthesis and hydroprocessing (HP) is a promising strategy to provide valuable chemicals and fuels based on renewable feedstocks. High yields of liquid products are essential for industrial implementation since short-chain side products like methane and CO reduce the overall carbon efficiency, which holds true especially for bi-functional Co/zeolite catalysts. In order to investigate the influence of the support material properties on the methane and CO selectivities in the combined FT and HP reaction, we synthesized four well-defined catalyst materials with similar cobalt particle sizes. The active material is supported on either meso- or microporous silicates or aluminosilicates. The catalytic properties are investigated in FT experiments at industrially relevant conditions (20â
bar, 200â260â°C) and correlated with inâ
situ x-ray absorption spectroscopy results to determine the chemical environment responsible for the selectivity observed. The origin of the high methane selectivity detected for crystalline and amorphous aluminosilicate was mainly traced back to the strong cobalt-support interactions. The high CO selectivity, observed only for crystalline zeolite materials, is driven by the presence of oxidized cobalt species, while the acidic support in combination with micropores and possible overcracking leads to the observed drop in the C selectivity
Treating treatment-resistant patients with panic disorder and agoraphobia: A randomized controlled switching trial
Background: Nonresponsiveness to therapy is generally acknowledged, but only a few studies have tested switching to psychotherapy. This study is one of the first to examine the malleability of treatment-resistant patients using acceptance and commitment therapy (ACT). Methods: This was a randomized controlled trial that included 43 patients diagnosed with primary panic disorder and/or agoraphobia (PD/A) with prior unsuccessful state-of-the-art treatment (mean number of previous sessions = 42.2). Patients were treated with an ACT manual administered by novice therapists and followed up for 6 months. They were randomized to immediate treatment (n = 33) or a 4-week waiting list (n = 10) with delayed treatment (n = 8). Treatment consisted of eight sessions, implemented twice weekly over 4 weeks. Primary outcomes were measured with the Panic and Agoraphobia Scale (PAS), the Clinical Global Impression (CGI), and the Mobility Inventory (MI). Results: At post-treatment, patients who received ACT reported significantly more improvements on the PAS and CGI (d = 0.72 and 0.89, respectively) than those who were on the waiting list, while improvement on the MI (d = 0.50) was nearly significant. Secondary outcomes were consistent with ACT theory. Follow-up assessments indicated a stable and continued improvement after treatment. The dropout rate was low (9%). Conclusions: Despite a clinically challenging sample and brief treatment administered by novice therapists, patients who received ACT reported significantly greater changes in functioning and symptomatology than those on the waiting list, with medium-to-large effect sizes that were maintained for at least 6 months. These proof-of-principle data suggest that ACT is a viable treatment option for treatment-resistant PD/A patients. Further work on switching to psychotherapy for nonresponders is clearly needed. © 2015 S. Karger AG, Basel
An analysis of innovation in textile companies: an efficiency approach
[EN] The elimination of trade contingency measures in 2005 triggered a process of renewal in the textile sector, requiring major investments. The divide between efficiency and innovation has become an issue of major importance for decision-making in the Spanish textile sector. This study provides quantitative data on the efficiency levels of innovative Spanish textile companies. The aim is to identify their distinguishing features and establish a possible pattern to follow. In addition, truncated regression is used to estimate the determinants of efficiency, in order to check the significance of innovation processes for firms.Puertas Medina, RM.; MartĂ Selva, ML.; Calafat Marzal, MC. (2020). An analysis of innovation in textile companies: an efficiency approach. Bulletin of Economic Research (Online). 72(1):63-76. https://doi.org/10.1111/boer.12210S6376721Banker, R. D., Charnes, A., & Cooper, W. W. (1984). Some Models for Estimating Technical and Scale Inefficiencies in Data Envelopment Analysis. Management Science, 30(9), 1078-1092. doi:10.1287/mnsc.30.9.1078Bastos F. &Nasir J.(2004).Productivity and the investment climate: What matters most?World Bank Policy Research Working Paper3335.Becker, S. O., & Egger, P. H. (2009). Endogenous product versus process innovation and a firmâs propensity to export. Empirical Economics, 44(1), 329-354. doi:10.1007/s00181-009-0322-6Beneito, P., CoscollĂĄ-Girona, P., Rochina-Barrachina, M. E., & Sanchis, A. (2015). Competitive Pressure and Innovation at the Firm Level. The Journal of Industrial Economics, 63(3), 422-457. doi:10.1111/joie.12079Bhandari, A. K., & Ray, S. C. (2011). TECHNICAL EFFICIENCY IN THE INDIAN TEXTILES INDUSTRY: A NON-PARAMETRIC ANALYSIS OF FIRM-LEVEL DATA. Bulletin of Economic Research, 64(1), 109-124. doi:10.1111/j.1467-8586.2010.00381.xCassiman, B., Golovko, E., & MartĂnez-Ros, E. (2010). Innovation, exports and productivity. International Journal of Industrial Organization, 28(4), 372-376. doi:10.1016/j.ijindorg.2010.03.005CrĂ©pon B. Duguet E. &Mairesse J.(1998).Research innovation and productivity an econometric analysis at the firm level. NBER Working Paper 6696.https://doi.org/10.1080/10438599800000031De Jorge-Moreno, J., & Rojas Carrasco, O. (2015). Technical efficiency and its determinants factors in Spanish textiles industry (2002-2009). Journal of Economic Studies, 42(3), 346-357. doi:10.1108/jes-06-2013-0085Diaz-Balteiro, L., Casimiro Herruzo, A., Martinez, M., & GonzĂĄlez-PachĂłn, J. (2006). An analysis of productive efficiency and innovation activity using DEA: An application to Spainâs wood-based industry. Forest Policy and Economics, 8(7), 762-773. doi:10.1016/j.forpol.2005.06.004Duch N.(2006).PosiciĂłn competitiva y estrategias de las empresas catalanas. AnĂĄlisis del Programa CrĂ©ixer (2003â2005). Documents de treball. CIDEM. Generalitat de Catalunya.Goedhuys, M., & Veugelers, R. (2012). Innovation strategies, process and product innovations and growth: Firm-level evidence from Brazil. Structural Change and Economic Dynamics, 23(4), 516-529. doi:10.1016/j.strueco.2011.01.004Harrison, R., Jaumandreu, J., Mairesse, J., & Peters, B. (2014). Does innovation stimulate employment? A firm-level analysis using comparable micro-data from four European countries. International Journal of Industrial Organization, 35, 29-43. doi:10.1016/j.ijindorg.2014.06.001Huergo, E., & Jaumandreu, J. (2004). Firmsâ age, process innovation and productivity growth. International Journal of Industrial Organization, 22(4), 541-559. doi:10.1016/j.ijindorg.2003.12.002Kouliavtsev, M., Christoffersen, S., & Russel, P. (2006). Productivity, Scale and Efficiency in the U.S. Textile Industry. Empirical Economics, 32(1), 1-18. doi:10.1007/s00181-006-0069-2Sanchez R. &Diaz A.(2013).Are large innovative firms more efficient?MRPA Paper n° 44592.Sellers R. Nicolau J. L. &Mas F. J.(2002).Eficiencia en la distribuciĂłn: Una aplicaciĂłn en el sector de agencias de viaje. Working paper serie ED N°17. Instituto Valenciano de Investigaciones EconĂłmicas. Retrieved fromhttp://hdl.handle.net/10045/23320Zheng J. Liu X. &Bigsten A.(2000).Efficiency Technical Progress and Best Practice in Chinese State Enterprises (1980â1994). Working Papers in Economics n 30 Department of Economics. Göteborg.https://doi.org/10.1016/S0147-5967(02)00010-
The ATLAS High Level Trigger Steering
The High Level Trigger (HLT) of the ATLAS experiment at the Large Hadron Collider receives events which pass the LVL1 trigger at ~75 kHz and has to reduce the rate to ~200 Hz while retaining the most interesting physics. It is a software trigger and performs the reduction in two stages: the LVL2 trigger and the Event Filter (EF). At the heart of the HLT is the Steering software. To minimise processing time and data transfers it implements the novel event selection strategies of seeded, step-wise reconstruction and early rejection. The HLT is seeded by regions of interest identified at LVL1. These and the static configuration determine which algorithms are run to reconstruct event data and test the validity of trigger signatures. The decision to reject the event or continue is based on the valid signatures, taking into account pre-scale and pass-through. After the EF, event classification tags are assigned for streaming purposes. Several powerful new features for commissioning and operation have been added: comprehensive monitoring is now built in to the framework; for validation and debugging, reconstructed data can be written out; the steering is integrated with the new configuration (presented separately), and topological and global triggers have been added. This paper will present details of the final design and its implementation, the principles behind it, and the requirements and constraints it is subject to. The experience gained from technical runs with realistic trigger menus will be described
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