11,058 research outputs found

    Distribution of the Timing, Trigger and Control Signals in the Endcap Cathode Strip Chamber System at CMS

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    This paper presents the implementation of the Timing, Trigger and Control (TTC) signal distribution tree in the Cathode Strip Chamber (CSC) sub-detector of the CMS Experiment at CERN. The key electronic component, the Clock and Control Board (CCB) is described in detail, as well as the transmission of TTC signals from the top of the system down to the front-end boards

    Random forests with random projections of the output space for high dimensional multi-label classification

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    We adapt the idea of random projections applied to the output space, so as to enhance tree-based ensemble methods in the context of multi-label classification. We show how learning time complexity can be reduced without affecting computational complexity and accuracy of predictions. We also show that random output space projections may be used in order to reach different bias-variance tradeoffs, over a broad panel of benchmark problems, and that this may lead to improved accuracy while reducing significantly the computational burden of the learning stage

    Huge decreases in the risk of breast cancer relapse over the last three decades

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    Introduction The aim of this study was to evaluate local and systemic breast cancer control by comparing the risk of relapse in breast cancer patients in 2003–2004 with that in 1972–1979 and in 1980–1986. Methods About 8,570 women diagnosed with invasive breast cancer in 2003–2004 were selected from the population-based Netherlands Cancer Registry and compared with 133 patients treated in 1972–1979 and 174 in 1980–1986. Five-year risk of relapse was calculated by the Kaplan–Meier method. Cox-proportional hazard models were applied to adjust for tumour size, nodal status and age at diagnosis. Results Patients diagnosed in 2003–2004 had smaller tumours and a less advanced nodal stage than patients diagnosed in 1972–1986. In 1972–1979, 1980–1986 and 2003–2004, treatment included mastectomy in 94%, 72% and 47%; postmastectomy radiotherapy in 75%, 70% and 30%; chemotherapy in 9%, 14% and 37% and hormonal therapy in 3%, 3% and 42% of patients, respectively. Five-year risk of locoregional and distant recurrence decreased from 37% and 34% to 15%, respectively. The 5-year risk of second primary breast cancer did not differ and was 1%, 4% and 2%, respectively. The improved relapse-free survival in patients diagnosed in 2003–2004 as compared with 1972–1979 hardly changed after adjustment (HR = 0.38, 95% CI = 0.28–0.52). Conclusion Over the last decades, local breast cancer therapies have become less rigorous, whereas systemic therapy use has increased. Simultaneously, the risk of breast cancer relapse has tremendously decreased. Future novel therapies may lead to such small additional decreases in relapse rates, while the long-term side effects in breast cancer survivors will increas

    Distributed utterances

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    I propose an apparatus for handling intrasentential change in context. The standard approach has problems with sentences with multiple occurrences of the same demonstrative or indexical. My proposal involves the idea that contexts can be complex. Complex contexts are built out of (“simple”) Kaplanian contexts by ordered n-tupling. With these we can revise the clauses of Kaplan’s Logic of Demonstratives so that each part of a sentence is taken in a different component of a complex context. I consider other applications of the framework: to agentially distributed utterances (ones made partly by one speaker and partly by another); to an account of scare-quoting; and to an account of a binding-like phenomenon that avoids what Kit Fine calls “the antinomy of the variable.

    Leray and LANS-α\alpha modeling of turbulent mixing

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    Mathematical regularisation of the nonlinear terms in the Navier-Stokes equations provides a systematic approach to deriving subgrid closures for numerical simulations of turbulent flow. By construction, these subgrid closures imply existence and uniqueness of strong solutions to the corresponding modelled system of equations. We will consider the large eddy interpretation of two such mathematical regularisation principles, i.e., Leray and LANSα-\alpha regularisation. The Leray principle introduces a {\bfi smoothed transport velocity} as part of the regularised convective nonlinearity. The LANSα-\alpha principle extends the Leray formulation in a natural way in which a {\bfi filtered Kelvin circulation theorem}, incorporating the smoothed transport velocity, is explicitly satisfied. These regularisation principles give rise to implied subgrid closures which will be applied in large eddy simulation of turbulent mixing. Comparison with filtered direct numerical simulation data, and with predictions obtained from popular dynamic eddy-viscosity modelling, shows that these mathematical regularisation models are considerably more accurate, at a lower computational cost.Comment: 42 pages, 12 figure

    Asymptomatic spinal cord lesions do not predict the time to disability in patients with early multiple sclerosis

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    BACKGROUND: The presence of asymptomatic spinal cord (SC) lesions in patients with clinically isolated syndrome (CIS) or relapsing-remitting multiple sclerosis (RRMS) predicts conversion to clinically definite multiple sclerosis (CDMS). The relation between asymptomatic SC abnormalities and disability progression warrants further investigation. OBJECTIVE: To determine the prognostic value of asymptomatic SC lesions in CIS and early RRMS with respect to the time to disability development. METHODS: Clinical and demographic data, brain and SC magnetic resonance imaging (MRI) were collected of CIS or early RRMS patients. Two main analyses were performed. For the first analysis, patients were divided into two groups: (1) patients with asymptomatic SC lesions and (2) patients without SC lesions and patients with symptomatic SC lesions. The second analysis excluded patients with symptomatic SC lesions. Incidence curves were used to analyse differences between these groups in time to the development of disability and time to a second relapse. RESULTS: A total of 178 patients were included, and 42 patients (23.6%) had asymptomatic SC lesions. No significant differences were found on the time to disability development or the time to a second event. CONCLUSION: Asymptomatic SC lesions early in the disease course do not predict the time to disability development in patients diagnosed with CIS or early RRMS

    Large Eddy Simulation of Turbulent Channel Flows by the Rational LES Model

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    The rational large eddy simulation (RLES) model is applied to turbulent channel flows. This approximate deconvolution model is based on a rational (subdiagonal Pade') approximation of the Fourier transform of the Gaussian filter and is proposed as an alternative to the gradient (also known as the nonlinear or tensor-diffusivity) model. We used a spectral element code to perform large eddy simulations of incompressible channel flows at Reynolds numbers based on the friction velocity and the channel half-width Re{sub tau} = 180 and Re{sub tau} = 395. We compared the RLES model with the gradient model. The RLES results showed a clear improvement over those corresponding to the gradient model, comparing well with the fine direct numerical simulation. For comparison, we also present results corresponding to a classical subgrid-scale eddy-viscosity model such as the standard Smagorinsky model.Comment: 31 pages including 15 figure
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