1,779 research outputs found

    A hardware abstraction layer for the MicroTCA-based Global Trigger for the CMS experiment at CERN

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    Der Large Hadron Collider (LHC) am CERN bei Genf produziert mit einer Frequenz von 40 MHz Teilchenkollisionen. Jede dieser Kollisionen benötigt nachdem sie vom CMS Detektor aufgezeichnet worden ist etwa 1 MB an Speicher. Um diese enorme Menge an Daten zu reduzieren wurde ein komplexes Filter-System entwickelt. Die erste Stufe dieses Systems nimmt der Level-1 Trigger ein, der die Rate an aufgezeichneten Kollisionen auf 100 kHz reduziert. Diese Kollisionen können anschließend von einer großen Rechenfarm analysiert und weiter gefiltert werden. Der LHC wird in absehbarer Zukunft ausgebaut werden um Kollisionen mit noch mehr beteiligten Teilchen zu produzieren, was eine Verbesserung des Level-1 Triggers notwendig macht. Diese Arbeit beschäftigt sich mit den Plänen zu diesem Ausbau innerhalb des Global Trigger (GT) Projekts und führte schlussendlich zur Entwicklung einer hardware abstraction layer (HAL), die entfernten Zugriff auf Hardware-Register über Ethernet erlaubt wie auch abstrakte Elemente zur Verfügung stellt um die Information in den Registern zu repräsentieren. Abschließend wird eine Studie über die Effizienz des Global Muon Trigger präsentiert die zu Verbesserungen für die Datennahme ab dem Jahr 2011 geführt hat.The Large Hadron Collider (LHC) based at CERN near Geneva collides proton bunches at a rate of 40 MHz. Each collision produces approximately 1 MB of data in the Compact Muon Solenoid (CMS) detector. In order to reduce this event rate to a more manageable amount, a complex filter system was developed. The first stage of this filter is the so-called Level-1 trigger. This system reduces the incoming event rate to 100 kHz which can then be analyzed and filtered further in a massive computing farm. The LHC is scheduled to be upgraded to provide collisions with even more particles involved thus making an upgrade of the Level-1 trigger necessary. This thesis is concerned with the upgrade plans of the GlobalTrigger (GT) project and ultimately lead to the development ofa hardware abstraction layer (HAL) which can provide remote register-level access via Ethernet as well as abstract items to represent the information stored in the registers. Finally a study of the Global Muon Trigger (GMT) efficiency is presented

    Measurement of differential cross sections for top quark pair production using the lepton plus jets final state in proton-proton collisions at 13 TeV

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    National Science Foundation (U.S.

    Particle-flow reconstruction and global event description with the CMS detector

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    The CMS apparatus was identified, a few years before the start of the LHC operation at CERN, to feature properties well suited to particle-flow (PF) reconstruction: a highly-segmented tracker, a fine-grained electromagnetic calorimeter, a hermetic hadron calorimeter, a strong magnetic field, and an excellent muon spectrometer. A fully-fledged PF reconstruction algorithm tuned to the CMS detector was therefore developed and has been consistently used in physics analyses for the first time at a hadron collider. For each collision, the comprehensive list of final-state particles identified and reconstructed by the algorithm provides a global event description that leads to unprecedented CMS performance for jet and hadronic tau decay reconstruction, missing transverse momentum determination, and electron and muon identification. This approach also allows particles from pileup interactions to be identified and enables efficient pileup mitigation methods. The data collected by CMS at a centre-of-mass energy of 8 TeV show excellent agreement with the simulation and confirm the superior PF performance at least up to an average of 20 pileup interactions

    Search for heavy resonances decaying to a top quark and a bottom quark in the lepton+jets final state in proton–proton collisions at 13 TeV

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    info:eu-repo/semantics/publishe

    Pseudorapidity and transverse momentum dependence of flow harmonics in pPb and PbPb collisions

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    info:eu-repo/semantics/publishe

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good
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