32,341 research outputs found

    Flightweight radiantly and actively cooled panel: Thermal and structural performance

    Get PDF
    A 2- by 4-ft flightweight panel was subjected to thermal/structural tests representative of design flight conditions for a Mach 6.7 transport and to off-design conditions simulating flight maneuvers and cooling system failures. The panel utilized Rene 41 heat shields backed by a thin layer of insulation to radiate away most of the 12 Btu/ft2-sec incident heating. A solution of ethylene glycol in water circulating through tubes in an aluminum-honeycomb-sandwich panel absorbed the remainder of the incident heating (0.8 Btu/sq ft-sec). The panel successfully withstood (1) 46.7 hr of radiant heating which included 53 thermal cycles and 5000 cycles of uniaxial inplane loading of + or - 1200 lfb/in; (2) simulated 2g-maneuver heating conditions and simulated cooling system failures without excessive temperatures on the structural panel; and (3) the extensive thermal/structural tests and the aerothermal tests reported in NASA TP-1595 without significant damage to the structural panel, coolant leaks, or hot-gas ingress to the structural panel

    The role of built environment energy efficiency in a sustainable UK energy economy

    Get PDF
    Energy efficiency in the built environment can make significant contributions to a sustainable energy economy. In order to achieve this, greater public awareness of the importance of energy efficiency is required. In the short term, new efficient domestic appliances, building technologies, legislation quantifying building plant performance, and improved building regulations to include installed plant will be required. Continuing these improvements in the longer term is likely to see the adoption of small-scale renewable technologies embedded in the building fabric. Internet-based energy services will see low-cost building energy management and control delivered to the mass market in order that plant can be operated and maintained at optimum performance levels and energy savings quantified. There are many technology options for improved energy performance of the building fabric and energy systems and it's not yet clear which will prove to be the most economic. Therefore, flexibility is needed in legislation and energy-efficiency initiatives

    Monetary costs of agitation in older adults with Alzheimer's disease in the UK: prospective cohort study

    Get PDF
    While nearly half of all people with Alzheimer's disease (AD) have agitation symptoms every month, little is known about the costs of agitation in AD. We calculated the monetary costs associated with agitation in older adults with AD in the UK from a National Health Service and personal social services perspective

    Nonequilibrium phase transition in a non integrable zero-range process

    Full text link
    The present work is an endeavour to determine analytically features of the stationary measure of a non-integrable zero-range process, and to investigate the possible existence of phase transitions for such a nonequilibrium model. The rates defining the model do not satisfy the constraints necessary for the stationary measure to be a product measure. Even in the absence of a drive, detailed balance with respect to this measure is violated. Analytical and numerical investigations on the complete graph demonstrate the existence of a first-order phase transition between a fluid phase and a condensed phase, where a single site has macroscopic occupation. The transition is sudden from an imbalanced fluid where both species have densities larger than the critical density, to a critical neutral fluid and an imbalanced condensate

    Annular Pancreatitis and Gastric Cancer

    Get PDF
    Annular pancreas can present in adult life, usually when inflammation of the pancreatic ring causes duodenal stenosis. Although peptic ulcer is often associated with annular pancreas, an association with gastric carcinoma has not been previously described. Here we report a patient with annular pancreas, chronic alcoholic pancreatitis and gastric carcinoma, who was successfully treated by radical proximal pancreatoduodenectomy

    The K(ππ)I=2K\to(\pi\pi)_{I=2} Decay Amplitude from Lattice QCD

    Full text link
    We report on the first realistic \emph{ab initio} calculation of a hadronic weak decay, that of the amplitude A2A_2 for a kaon to decay into two \pi-mesons with isospin 2. We find ReA2=(1.436±0.063stat±0.258syst)108GeVA_2=(1.436\pm 0.063_{\textrm{stat}}\pm 0.258_{\textrm{syst}})\,10^{-8}\,\textrm{GeV} in good agreement with the experimental result and for the hitherto unknown imaginary part we find {Im}A2=(6.83±0.51stat±1.30syst)1013GeV\,A_2=-(6.83 \pm 0.51_{\textrm{stat}} \pm 1.30_{\textrm{syst}})\,10^{-13}\,{\rm GeV}. Moreover combining our result for Im\,A2A_2 with experimental values of Re\,A2A_2, Re\,A0A_0 and ϵ/ϵ\epsilon^\prime/\epsilon, we obtain the following value for the unknown ratio Im\,A0A_0/Re\,A0A_0 within the Standard Model: ImA0/ReA0=1.63(19)stat(20)syst×104\mathrm{Im}\,A_0/\mathrm{Re}\,A_0=-1.63(19)_{\mathrm{stat}}(20)_{\mathrm{syst}}\times10^{-4}. One consequence of these results is that the contribution from Im\,A2A_2 to the direct CP violation parameter ϵ\epsilon^{\prime} (the so-called Electroweak Penguin, EWP, contribution) is Re(ϵ/ϵ)EWP=(6.52±0.49stat±1.24syst)×104(\epsilon^\prime/\epsilon)_{\mathrm{EWP}} = -(6.52 \pm 0.49_{\textrm{stat}} \pm 1.24_{\textrm{syst}}) \times 10^{-4}. We explain why this calculation of A2A_2 represents a major milestone for lattice QCD and discuss the exciting prospects for a full quantitative understanding of CP-violation in kaon decays.Comment: 5 pages, 1 figur

    Standard-model prediction for direct CP violation in KππK\to\pi\pi decay

    Get PDF
    We report the first lattice QCD calculation of the complex kaon decay amplitude A0A_0 with physical kinematics, using a 323×6432^3\times 64 lattice volume and a single lattice spacing aa, with 1/a=1.3784(68)1/a= 1.3784(68) GeV. We find Re(A0)=4.66(1.00)(1.26)×107(A_0) = 4.66(1.00)(1.26) \times 10^{-7} GeV and Im(A0)=1.90(1.23)(1.08)×1011(A_0) = -1.90(1.23)(1.08) \times 10^{-11} GeV, where the first error is statistical and the second systematic. The first value is in approximate agreement with the experimental result: Re(A0)=3.3201(18)×107(A_0) = 3.3201(18) \times 10^{-7} GeV while the second can be used to compute the direct CP violating ratio Re(ε/ε)=1.38(5.15)(4.59)×104(\varepsilon'/\varepsilon)=1.38(5.15)(4.59)\times 10^{-4}, which is 2.1σ2.1\sigma below the experimental value 16.6(2.3)×10416.6(2.3)\times 10^{-4}. The real part of A0A_0 is CP conserving and serves as a test of our method while the result for Re(ε/ε)(\varepsilon'/\varepsilon) provides a new test of the standard-model theory of CP violation, one which can be made more accurate with increasing computer capability.Comment: 9 pages, 3 figures. Updated to match published versio

    SYSTEMS-2: a randomised phase II study of radiotherapy dose escalation for pain control in malignant pleural mesothelioma

    Get PDF
    SYSTEMS-2 is a randomised study of radiotherapy dose escalation for pain control in 112 patients with malignant pleural mesothelioma (MPM). Standard palliative (20Gy/5#) or dose escalated treatment (36Gy/6#) will be delivered using advanced radiotherapy techniques and pain responses will be compared at week 5. Data will guide optimal palliative radiotherapy in MPM
    corecore