987 research outputs found

    Distress thermometer (SUDS). modified for use in participatory arts evaluations

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    Subjective Units of Distress Scale was designed in 1969 by Wolpe. It is frequently used in CBT treatments concerning distress and for research purposes. We have re-designed this scale with just three anchor points on the thermometer, encouraging subjective self-rating. The scale is designed to look non-medical, and to encourage engagement in arts and health settings through simple, sophisticated design and clear instructions which refrain from medical instructions and labelling

    Real Time Wake Computations using Lattice Boltzmann Method on Many Integrated Core Processors

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    This paper puts forward an efficient Lattice Boltzmann method for use as a wake simulator suitable for real-time environments. The method is limited to low speed incompressible flow but is very efficient and can be used to compute flows “on the fly”. In particular, many-core machines allow for the method to be used with the need of very expensive parallel clusters. Results are shown here for flows around cylinders and simple ship shapes

    Real Time Wake Computations using Lattice Boltzmann Method on Many Integrated Core Processors

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    This paper puts forward an efficient Lattice Boltzmann method for use as a wake simulator suitable for real-time environments. The method is limited to low speed incompressible flow but is very efficient and can be used to compute flows “on the fly”. In particular, many-core machines allow for the method to be used with the need of very expensive parallel clusters. Results are shown here for flows around cylinders and simple ship shapes

    Fast prediction of transonic aeroelasticity using computational fluid dynamics

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    The exploitation of computational fluid dynamics for non linear aeroelastic simulations is mainly based on time domain simulations of the Euler and Navier-Stokes equations coupled with structural models. Current industrial practice relies heavily on linear methods which can lead to conservative design and flight envelope restrictions. The significant aeroelastic effects caused by nonlinear aerodynamics include the transonic flutter dip and limit cycle oscillations. An intensive research effort is underway to account for aerodynamic nonlinearity at a practical computational cost.To achieve this a large reduction in the numbers of degrees of freedoms is required and leads to the construction of reduced order models which provide compared with CFD simulations an accurate description of the dynamical system at much lower cost. In this thesis we consider limit cycle oscillations as local bifurcations of equilibria which are associated with degenerate behaviour of a system of linearised aeroelastic equations. This extra information can be used to formulate a method for the augmented solve of the onset point of instability - the flutter point. This method contains all the fidelity of the original aeroelastic equations at much lower cost as the stability calculation has been reduced from multiple unsteady computations to a single steady state one. Once the flutter point has been found, the centre manifold theory is used to reduce the full order system to two degrees of freedom. The thesis describes three methods for finding stability boundaries, the calculation of a reduced order models for damping and for limit cycle oscillations predictions. Results are shown for aerofoils, and the AGARD, Goland, and a supercritical transport wing. It is shown that the methods presented allow results comparable to the full order system predictions to be obtained with CPU time reductions of between one and three orders of magnitude

    Parallel Performance for a Real Time Lattice Boltzmann Code

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    The paper will present the details of a Lattice Boltzmann solver running in real time for unsteady wake computations. In addition to algorithmic implementation, computational results, single core and parallel optimization of the methods are also discussed

    MobGeoSen: facilitating personal geosensor data collection and visualization using mobile phones

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    Mobile sensing and mapping applications are becoming more prevalent because sensing hardware is becoming more portable and more affordable. However, most of the hardware uses small numbers of fixed sensors that report and share multiple sets of environmental data which raises privacy concerns. Instead, these systems can be decentralized and managed by individuals in their public and private spaces. This paper describes a robust system called MobGeoSens which enables individuals to monitor their local environment (e.g. pollution and temperature) and their private spaces (e.g. activities and health) by using mobile phones in their day to day life

    An implicit hybrid method for the computation of rotorcraft flows

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    There is a wide variety of CFD grid types including Cartesian, structured, unstructured and hybrids, as well as, numerous methodologies of combining these to reduce the time required to generate high-quality grids around complex configurations. If the grid methodologies were implemented in different codes, they should be written in such a way as to obtain the maximum performance from the available computer resources. A common interface should also be required to allow for ease of use. However, it is very time consuming to develop, maintain and add extra functionally to different codes. This paper examines the possibility of taking an existing CFD solver, the Helicopter Multi-Block (HMB) CFD method, and implementing a new grid type while reusing as much as possible the original code base. The paper presents some of the challenges encountered in extending the code which was written for a single mesh type, to a more flexible solver that is still computationally efficient but can cope with a variety of grid types

    Method for calculating rotors with active gurney flaps

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    This paper builds on the Helicopter Multi-Block version 2 computational-fluid-dynamics solver of the University of Liverpool and demonstrates the implementation and use of Gurney flaps on wings and rotors. The idea is to flag any cell face within the computational mesh with a solid, no-slip boundary condition. Hence, the infinitely thin Gurney can be approximated by “blocking cells” in the mesh. Comparison between thick Gurney flaps and infinitely thin Gurneys showed no difference on the integrated loads; the same flow structure was captured and the same vortices were identified ahead and behind the Gurney. The results presented for various test cases suggest that the method is simple and efficient, and it can therefore be used for routine analysis of rotors with Gurney flaps. Moreover, the current method adds to the flexibility of the solver because no special grids are required, and Gurney flaps can be easily implemented. Simple two-dimensional aerofoil, three-dimensional wing, and rotors in hover and forward flight were tested with fixed, linearly actuated, and swinging Gurneys, and the ability of the code to deploy a Gurney flap within the multiblock mesh is highlighted. The need for experimental data suitable for validation of computational-fluid-dynamics methods for cases of rotors with Gurney flaps is also highlighted

    Assessment of the Harmonic Balance Method for Rotor Blade Performance Predictions

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    This paper presents an assessment of the harmonic balance method for rotor blade performance predictions. The harmonic balance method within the HMB3 solver of Glasgow University has been extended to the use with overset grids, and results are presented for the PSP and AH-64A rotor blades in hover and forward flight. The predictions are compared with results from steady-state and time marching simulations. In particular, the harmonic balance method is assessed for capturing key flow features, such as the strength of the advancing blade shockwave and retreating side blade dynamic stall. The limitations of the method are also discussed. The findings show that the harmonic balance method is a promising alternative to time-marching simulations due to a significant reduction in computational costs, leading to the potential use of high-fidelity Navier-Stokes methods in optimisation studies

    Debris Disk Structure and Morphology as Revealed by Aggressive STIS Multi-Roll Coronagraphy: A New Look at Some Old Friends

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    We present new imaging results from a well-selected sample of II circumstellar debris disks, all with HST pedigree, using STIS visible-light 6-roll PSF-template subtracted coronagraphy (PSFTSC). These new observations, pushing HST to its highest levels of coronagraphic performance, simultaneously probe both the interior regions of these debris systems, with inner working distances < app 8 AU for half the stars in this sample (corresponding to the giant planet and Kuiper belt regions within our own solar system), and the exterior regions far beyond. These new images enable direct inter-comparison of the architectures of these exoplanetary debris systems in the context of our own Solar System: These observations also permit us, for the first time, to characterize material in these regions at high spatial resolution and identify disk sub-structures that are signposts of planet formation and evolution; in particular, asymmetries and non-uniform debris structures that signal the presence of co-orbiting perturbing planets, and dynamical interactions (e.g., resulting in posited small grain stripping and disk "pollution") with the ISM. We focus here on recently acquired and reduced images of he circumstellar debris systems about: AU Mic (edge-on, and @ 10 pc the closest star in our sample), HD 61005, HD 32297 and HD 15115 (all with morphologies strongly suggestive of ISM wind interactions), HD 181327 & HDI07146 (close to face-on with respectively narrow and broad debris rings), and MP Mus (a "mature" proto-planetary disk hosted by a cTTS). All of our objects were previously observed in the near-IR with inferior spatial resolution and imaging efficacy, but with NICMOS r = 0.3" inner working angle (IWA) comparable to STIS multi-roll coronagraphy. The combination of new optical and existing near-IR imaging can strongly constrain the dust properties, thus enabling an assessment of grain processing and planetesimal populations. These results will directly inform upon the posited planet formation mechanisms that occur after the approximately 10 My epoch of gas depletion, a time in our solar system when giant planets were migrating and terrestrial planets were forming, and directly test theoretical models of these processes. These observations lmiquely probe both into the interior regions of these systems and are sensitive to and spatially resolve low surface-brightness (SB) material at large stellocentric distances with spatial resolution comparable to ACS and with augmenting NICMOS near-IR disk photometry in hand
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