112 research outputs found

    Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser

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    We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ΔE/E=1.1⋅10−4\Delta E/E = 1.1\cdot 10^{-4} and wave-number resolution of Δk/k=3⋅10−3\Delta k/k = 3\cdot 10^{-3}, allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/5.2/\AA\ in 100 separate bins, with only 0.34\% wavenumber blurring. The dispersion of 0.418~eV/13.5 Ό13.5\,\mum agrees with predictions within 1.3\%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic HAPG spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1~eV and a significant range of wavenumbers must be covered in one exposure

    The First Brown Dwarf Discovered by the Backyard Worlds: Planet 9 Citizen Science Project

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    The Wide-field Infrared Survey Explorer (WISE) is a powerful tool for finding nearby brown dwarfs and searching for new planets in the outer solar system, especially with the incorporation of NEOWISE and NEOWISE-Reactivation data. So far, searches for brown dwarfs in WISE data have yet to take advantage of the full depth of the WISE images. To efficiently search this unexplored space via visual inspection, we have launched a new citizen science project, called "Backyard Worlds: Planet 9," which asks volunteers to examine short animations composed of difference images constructed from time-resolved WISE coadds. We report the discovery of the first new substellar object found by this project, WISEA J110125.95+540052.8, a T5.5 brown dwarf located approximately 34 pc from the Sun with a total proper motion of ∌\sim0.7 as yr−1^{-1}. WISEA J110125.95+540052.8 has a WISE W2W2 magnitude of W2=15.37±0.09W2=15.37 \pm 0.09, this discovery demonstrates the ability of citizen scientists to identify moving objects via visual inspection that are 0.9 magnitudes fainter than the W2W2 single-exposure sensitivity, a threshold that has limited prior motion-based brown dwarf searches with WISE.Comment: 9 pages, 4 figures, 1 table. Accepted for publication in the Astrophysical Journal Letter

    Modelling environment for holistic vehicle simulation

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    As the complexity of road vehicles increases with time, the importance of CAE tools to the product development cycle increases as well. A holistic vehicle simulation capability is necessary for front-loading component, subsystem, and controller design, for the early detection of component and subsystem design flaws, as well as for the model-based calibration of powertrain control modules. The current document explores the concept of holistic vehicle simulation by means of developing and testing a Simulink-based multidisciplinary modelling environment (MME), modular in nature and capable of connecting to subsystem models developed in different environments, thus supporting holistic vehicle simulation on a company-wide scale. The developed environment is tested via the integration of subsystem models built in different commercial software packages within the environment. The simulation results generated from equivalent vehicle models developed in three competing platforms are compared and the advantages and limitations of the different methods of model integration to the master holistic vehicle simulation are discussed

    Automated model based engine calibration procedure using co-simulation

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    The final validation and sign-off of a production powertrain control module (PCM) calibration is a time-consuming and expensive task and requires a high degree of expertise. There are two main reasons for this; firstly, the validation test is an iterative process due to the fact that calibration changes may affect the true operating point of the engine at the desired test point. Secondly, modifications to the calibration require expert knowledge of the complete control strategy so as to improve the correlation to validation data without potentially negatively impacting the correlated mapping points. This paper describes the implementation of an optimisation routine on a virtual platform in order to both reduce the requirement for experimental testing during the validation procedure, and for development of the optimisation routine itself prior to execution on the engine dynamometer. It is shown that in simulation, the optimisation routine is capable of producing an acceptable calibration within just 5 iterations, reducing the 11-week process down to just a few days. It is also concluded that there are also a number of further improvements that could be made to further improve the efficiency of this process

    Changing Student Attitudes Toward Interprofessional Learning and Collaboration: Partnering with Healthcare Mentors in the Academic Setting

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    Healthcare Mentor Project Individuals with one or more chronic health conditions Share their time with students Help students understand how to provide effective care Participation helps to make learning more authenti

    Developing the Enquiring Student and Enhancing the Research-Teaching Interface: Student-led Pedagogical Research and Educational Initiatives in Enquiry Based Learning

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    This paper describes the progress of a project running at the University of Glasgow to develop elements of Enquiry Based Learning (EBL) in undergraduate degree courses across a range of disciplines. It focuses on the second part of the project but an overview of the first part is also given. During phase 1 of the project, in the summer of 2007, seven undergraduate students spent four weeks working together exploring enquiry based learning (EBL) in the institution’s central, educational development unit. This phase was approached as an EBL exercise itself; the student groups were given full responsibility for the process with the proviso that by the end of this phase they would have developed a guide for staff and students about EBL. The second phase of the project continues throughout the academic year 07/08. Here, each student worked alongside a member of staff from their department of study to develop discipline specific EBL activities taking a research-informed approach to this development. All pairings were charged with introducing EBL such that no major course change procedures had to be followed; this hopefully ensured the sustainability of such adjustments. Staff and students involved in the project represent dentistry, chemistry, biology, theology, law and psychology and the courses under development range from large first year classes to small honours level courses. An overview of the range of enquiry-based learning developments within the courses will be described

    Developing the Enquiring Student and Enhancing the Research-Teaching Interface: Student-led Pedagogical Research and Educational Initiatives in Enquiry Based Learning

    Get PDF
    This paper describes the progress of a project running at the University of Glasgow to develop elements of Enquiry Based Learning (EBL) in undergraduate degree courses across a range of disciplines. It focuses on the second part of the project but an overview of the first part is also given. During phase 1 of the project, in the summer of 2007, seven undergraduate students spent four weeks working together exploring enquiry based learning (EBL) in the institution’s central, educational development unit. This phase was approached as an EBL exercise itself; the student groups were given full responsibility for the process with the proviso that by the end of this phase they would have developed a guide for staff and students about EBL. The second phase of the project continues throughout the academic year 07/08. Here, each student worked alongside a member of staff from their department of study to develop discipline specific EBL activities taking a research-informed approach to this development. All pairings were charged with introducing EBL such that no major course change procedures had to be followed; this hopefully ensured the sustainability of such adjustments. Staff and students involved in the project represent dentistry, chemistry, biology, theology, law and psychology and the courses under development range from large first year classes to small honours level courses. An overview of the range of enquiry-based learning developments within the courses will be described

    The Speed of Sound in Methane under Conditions of the Thermal Boundary Layer of Uranus

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    We present the first direct observations of acoustic waves in warm dense matter. We analyze wavenumber- and energy-resolved X-ray spectra taken from warm dense methane created by laser-heating a cryogenic liquid jet. X-ray diffraction and inelastic free electron scattering yield sample conditions of 0.3±\pm0.1 eV and 0.8±\pm0.1 g/cm3^3, corresponding to a pressure of ∌\sim13 GPa and matching the conditions predicted in the thermal boundary layer between the inner and outer envelope of Uranus. Inelastic X-ray scattering was used to observe the collective oscillations of the ions. With a highly improved energy resolution of ∌\sim50 meV, we could clearly distinguish the Brillouin peaks from the quasi-elastic Rayleigh feature. Data at different wavenumbers were used to obtain a sound speed of 5.9±\pm0.5 km/s, which enabled us to validate the use of Birch's law in this new parameter regime.Comment: 7 pages, 4 figures with supplementary informatio
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