6,623 research outputs found

    Comments on "Wall-plug (AC) power consumption of a very high energy e+/e- storage ring collider" by Marc Ross

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    The paper arXiv:1308.0735 questions some of the technical assumptions made by the TLEP Steering Group when estimating in arXiv:1305.6498 the power requirement for the very high energy e+e- storage ring collider TLEP. We show that our assumptions are based solidly on CERN experience with LEP and the LHC, as well accelerators elsewhere, and confirm our earlier baseline estimate of the TLEP power consumption.Comment: 6 page

    Local Complexity of Polygons

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    Many problems in Discrete and Computational Geometry deal with simple polygons or polygonal regions. Many algorithms and data-structures perform considerably faster, if the underlying polygonal region has low local complexity. One obstacle to make this intuition rigorous, is the lack of a formal definition of local complexity. Here, we give two possible definitions and show how they are related in a combinatorial sense. We say that a polygon PP has point visibility width w=pvww=pvw, if there is no point q∈Pq\in P that sees more than ww reflex vertices. We say that a polygon PP has chord visibility width w=cvww=cvw , if there is no chord c=seg(a,b)⊂Pc=\textrm{seg}(a,b)\subset P that sees more than w reflex vertices. We show that cvw≀pvwO(pvw), cvw \leq pvw ^{O( pvw )}, for any simple polygon. Furthermore, we show that there exists a simple polygon with cvw≄2Ω(pvw). cvw \geq 2^{\Omega( pvw )}.Comment: 7 pages, 5 figure

    Observation of coasting beam at the HERA Proton--Ring

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    We present data collected with the HERA-B wire target which prove the existence of coasting beam at the HERA proton storage ring. The coasting beam is inherently produced by the proton machine operation and is not dominated by target effects.Comment: 17 pages (Latex), 12 figures (Enc. Postscript

    Planning the Future of U.S. Particle Physics (Snowmass 2013): Chapter 6: Accelerator Capabilities

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    These reports present the results of the 2013 Community Summer Study of the APS Division of Particles and Fields ("Snowmass 2013") on the future program of particle physics in the U.S. Chapter 6, on Accelerator Capabilities, discusses the future progress of accelerator technology, including issues for high-energy hadron and lepton colliders, high-intensity beams, electron-ion colliders, and necessary R&D for future accelerator technologies.Comment: 26 page

    The Development of a Well-Being Program for Occupational Therapy Graduate Students

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    High levels of stress among occupational therapy graduate students have led to the adoption of unhealthy coping habits such as poor nutrition, little exercise, and disrupted sleep. In response, many institutions have explored programming and even curricular changes to support student well-being. However, very few are built upon a strong theoretical foundation to address holistic well-being. Therefore, this paper describes how logic modeling was used to develop a student well-being program based on Facilitating Learning and Occupational Well-Being Using Research-Based Initiatives for Student Health (FLOURISH), a theoretical approach rooted in the Person-Environment-Occupation Performance Model. A well-being program delivered via a virtual community of practice for entry-level students at a Midwestern occupational therapy program was created to decrease stress and enhance overall well-being for the performance of learning. The program consisted of eight 50-minute sessions that met once per week and included topics of physical, mental, sociocultural, environmental, and occupational well-being. The student well-being program is one viable option that shows promise to empower students with a theoretical approach to address personal and professional well-being, which has the potential to translate into professional practice. In this article, we describe the well-being program and the theoretical approach in detail and illustrate how it can be used to improve occupational therapy student well-being

    Three-Axis Distributed Fiber Optic Strain Measurement in 3D Woven Composite Structures

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    Recent advancements in composite materials technologies have broken further from traditional designs and require advanced instrumentation and analysis capabilities. Success or failure is highly dependent on design analysis and manufacturing processes. By monitoring smart structures throughout manufacturing and service life, residual and operational stresses can be assessed and structural integrity maintained. Composite smart structures can be manufactured by integrating fiber optic sensors into existing composite materials processes such as ply layup, filament winding and three-dimensional weaving. In this work optical fiber was integrated into 3D woven composite parts at a commercial woven products manufacturing facility. The fiber was then used to monitor the structures during a VARTM manufacturing process, and subsequent static and dynamic testing. Low cost telecommunications-grade optical fiber acts as the sensor using a high resolution commercial Optical Frequency Domain Reflectometer (OFDR) system providing distributed strain measurement at spatial resolutions as low as 2mm. Strain measurements using the optical fiber sensors are correlated to resistive strain gage measurements during static structural loading. Keywords: fiber optic, distributed strain sensing, Rayleigh scatter, optical frequency domain reflectometr

    The Development of a Well-Being Program for Occupational Therapy Graduate Students

    Get PDF
    High levels of stress among occupational therapy graduate students have led to the adoption of unhealthy coping habits such as poor nutrition, little exercise, and disrupted sleep. In response, many institutions have explored programming and even curricular changes to support student well-being. However, very few are built upon a strong theoretical foundation to address holistic well-being. Therefore, this paper describes how logic modeling was used to develop a student well-being program based on Facilitating Learning and Occupational Well-Being Using Research-Based Initiatives for Student Health (FLOURISH), a theoretical approach rooted in the Person-Environment-Occupation Performance Model. A well-being program delivered via a virtual community of practice for entry-level students at a Midwestern occupational therapy program was created to decrease stress and enhance overall well-being for the performance of learning. The program consisted of eight 50-minute sessions that met once per week and included topics of physical, mental, sociocultural, environmental, and occupational well-being. The student well-being program is one viable option that shows promise to empower students with a theoretical approach to address personal and professional well-being, which has the potential to translate into professional practice. In this article, we describe the well-being program and the theoretical approach in detail and illustrate how it can be used to improve occupational therapy student well-being

    Prospects for the Search for a Standard Model Higgs Boson in ATLAS using Vector Boson Fusion

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    The potential for the discovery of a Standard Model Higgs boson in the mass range m_H < 2 m_Z in the vector boson fusion mode has been studied for the ATLAS experiment at the LHC. The characteristic signatures of additional jets in the forward regions of the detector and of low jet activity in the central region allow for an efficient background rejection. Analyses for the H -> WW and H -> tau tau decay modes have been performed using a realistic simulation of the expected detector performance. The results obtained demonstrate the large discovery potential in the H -> WW decay channel and the sensitivity to Higgs boson decays into tau-pairs in the low-mass region around 120 GeV.Comment: 20 pages, 13 ps figures, uses EPJ style fil

    A High Luminosity e+e- Collider to study the Higgs Boson

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    A strong candidate for the Standard Model Scalar boson, H(126), has been discovered by the Large Hadron Collider (LHC) experiments. In order to study this fundamental particle with unprecedented precision, and to perform precision tests of the closure of the Standard Model, we investigate the possibilities offered by An e+e- storage ring collider. We use a design inspired by the B-factories, taking into account the performance achieved at LEP2, and imposing a synchrotron radiation power limit of 100 MW. At the most relevant centre-of-mass energy of 240 GeV, near-constant luminosities of 10^34 cm^{-2}s^{-1} are possible in up to four collision points for a ring of 27km circumference. The achievable luminosity increases with the bending radius, and for 80km circumference, a luminosity of 5 10^34 cm^{-2}s^{-1} in four collision points appears feasible. Beamstrahlung becomes relevant at these high luminosities, leading to a design requirement of large momentum acceptance both in the accelerating system and in the optics. The larger machine could reach the top quark threshold, would yield luminosities per interaction point of 10^36 cm^{-2}s^{-1} at the Z pole (91 GeV) and 2 10^35 cm^{-2}s^{-1} at the W pair production threshold (80 GeV per beam). The energy spread is reduced in the larger ring with respect to what is was at LEP, giving confidence that beam polarization for energy calibration purposes should be available up to the W pair threshold. The capabilities in term of physics performance are outlined.Comment: Submitted to the European Strategy Preparatory Group 01-04-2013 new version as re-submitted to PRSTA
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