3,354 research outputs found

    Icing Characteristics and Anti-Icing Heat Requirements for Hollow and Ternally Modified Gas-Heated Inlet Guide Vanes

    Get PDF
    A two-dimensional inlet-guide-vane cascade was investigated to determine the effects of ice formations on the pressure losses across the guide vanes and to evaluate the heated gas flow and temperature required to prevent Icing at various conditions. A gas flow of approximately 0.4 percent of the inlet-air flow was necessary for anti-icing a hollow guide-vane stage at an inlet-gas temperature of 500 F under the following icing conditions: air velocity, 280 miles per hour; water content, 0.9 gram per cubic meter; and Inlet-air static temperature, 00 F. Also presented are the anti-icing gas flows required with modifications of the hollow Internal gas passage, which show heatinput savings greater than 50 percent

    Enhancing creative problem solving and creative self-efficacy: a preliminary study

    Get PDF
    The ability to improve creative problem solving (CPS) is considered to be an important resource in a variety of fields such as education (see Murdock, 2003) and business (see Thompson, 2003). Previous research suggests that interventions aimed at training people to improve their CPS skills can be effective, however it is not always clear what tools are being used and it is sometimes difficult to untangle the effect the different tools are having (see Vernon, Hocking, & Tyler, 2016, for a review). This study therefore aimed to utilise an empirically- based creativity toolkit in an 8 week training program aimed at enhancing students' CPS skills. The intervention group was comprised of 33 psychology students who signed up to undertake 8 weeks of CPS training and the control group (n = 9) were matched for contact time, undertaking 8 weeks of cognitive psychology lectures instead. In week 1 (Time 1) and week 8 (Time 2) all participants were assessed using two Unusual Uses Tasks (UUT) and a Creative Problem Solving (CPS) task and were also asked to fill out measures of creative self-efficacy. Analyses revealed that whilst the control group showed no improvement on any of the measures from Time 1 to Time 2, the intervention group showed a significant increase in both their creative self-efficacy and also their levels of creativity on both the UUT and CPS tasks. Whilst a follow- up study utilising a larger control group is ideally needed, these preliminary findings nonetheless support the use of this empirically based creativity toolkit for enhancing creativity problem solving skills

    Investigation of external refrigeration systems for long term cryogenic storage Final report

    Get PDF
    Data on external refrigeration systems for space storage of cryogens for long period

    Investigation of external refrigeration systems for long-term cryogenic storage

    Get PDF
    Evaluation of cryogenic refrigeration systems for space application

    SUSY dark matter and lepton flavor violation

    Full text link
    We study lepton flavor-violating (LFV) processes within a supersymmetric type-I seesaw framework with flavor-blind universal boundary conditions, properly accounting for the effect of the neutrino sector on the dark matter relic abundance. We consider several possibilities for the neutrino Yukawa coupling matrix and show that in regions of SUSY parameter space that yield the correct neutralino relic density, LFV rates can differ from naive estimates by up to two orders of magnitude. Contrary to common belief, we find that current LFV limits do not exclude neutrino Yukawa couplings larger than top Yukawa couplings. We introduce the ISAJET-M program that was used for the computations.Comment: 37 pages, 9 figures, 6 tables. Version to appear in PR

    Implications of a 125 GeV Higgs scalar for LHC SUSY and neutralino dark matter searches

    Full text link
    The ATLAS and CMS collaborations have reported an excess of events in the \gamma\gamma, ZZ^*\to 4\ell and WW^* search channels at an invariant mass m \simeq 125 GeV, which could be the first evidence for the long-awaited Higgs boson. We investigate the consequences of requiring m_h\simeq 125 GeV in both the mSUGRA and NUHM2 SUSY models. In mSUGRA, large values of trilinear soft breaking parameter |A_0| are required, and universal scalar m_0\agt 0.8 TeV is favored so that we expect squark and slepton masses typically in the multi-TeV range. This typically gives rise to an "effective SUSY" type of sparticle mass spectrum. In this case, we expect gluino pair production as the dominant sparticle creation reaction at LHC. For m_0< 5 TeV, the superpotential parameter \mu > 2 TeV and m_A> 0.8 TeV, greatly restricting neutralino annihilation mechanisms. These latter conclusions are softened if m_0\sim 10-20 TeV or if one proceeds to the NUHM2 model. The standard neutralino abundance tends to be far above WMAP-measured values unless the neutralino is higgsino-like. We remark upon possible non-standard (but perhaps more attractive) cosmological scenarios which can bring the predicted dark matter abundance into accord with the measured value, and discuss the implications for direct and indirect detection of neutralino cold dark matter.Comment: 24 pages including 23 .eps figures; updated version 3 contains also b-> tau+nu branching fractio

    Spectroscopic Measurements Of Temperature And Plasma Impurity Concentration During Magnetic Reconnection At The Swarthmore Spheromak Experiment

    Get PDF
    Electron temperature measurements during counterhelicity spheromak merging studies at the Swarthmore Spheromak Experiment (SSX) [M. R. Brown, Phys. Plasmas 6, 1717 (1999)] are presented. VUV monochromator measurements of impurity emission lines are compared with model spectra produced by the non-LTE excitation kinematics code PRISMSPECT [J. J. MacFarlane et al., in Proceedings of the Third Conference on Inertial Fusion Science and Applications (2004)] to yield the electron temperature in the plasma with 1 mu s time resolution. Average T(e) is seen to increase from 12 to 19 eV during spheromak merging. Average C III ion temperature, measured with a new ion Doppler spectrometer (IDS) [C. D. Cothran et al., Rev. Sci. Instrum. 77, 063504 (2006)], likewise rises during spheromak merging, peaking at similar to 22 eV, but a similar increase in T(i) is seen during single spheromak discharges with no merging. The VUV emission line measurements are also used to constrain the concentrations of various impurities in the SSX plasma, which are dominated by carbon, but include some oxygen and nitrogen. A burst of soft x-ray emission is seen during reconnection with a new four-channel detector (SXR). There is evidence for spectral changes in the soft x-ray emission as reconnection progresses, although our single-temperature equilibrium spectral models are not able to provide adequate fits to all the SXR data. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3099603

    Relationship between Intelligence and Criterion Task Set Performance1

    Get PDF
    ↵1 This research was sponsored in part by the Workload and Ergonomics Branch of the Armstrong Aerospace Medical Research Laboratory, United States Air Force, under Contract F33615-85-D-0514 through the Southeastern Center for Electrical Engineering Education (SCEEEHER/86-9). The United States Government is authorized to reproduce and distribute reprints for government purposes notwithstanding any copyright notation hereon. The authors wish to thank Gary Reid for his interest and support in the completion of this projectYeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

    Supersymmetry discovery potential of the LHC at s=\sqrt{s}=10 and 14 TeV without and with missing ETE_T

    Full text link
    We examine the supersymmetry (SUSY) reach of the CERN LHC operating at s=10\sqrt{s}=10 and 14 TeV within the framework of the minimal supergravity model. We improve upon previous reach projections by incorporating updated background calculations including a variety of 2→n2\to n Standard Model (SM) processes. We show that SUSY discovery is possible even before the detectors are understood well enough to utilize either ETmissE_T^{\rm miss} or electrons in the signal. We evaluate the early SUSY reach of the LHC at s=10\sqrt{s}=10 TeV by examining multi-muon plus ≥4\ge4 jets and also dijet events with {\it no} missing ETE_T cuts and show that the greatest reach in terms of m1/2m_{1/2} occurs in the dijet channel. The reach in multi-muons is slightly smaller in m1/2m_{1/2}, but extends to higher values of m0m_0. We find that an observable multi-muon signal will first appear in the opposite-sign dimuon channel, but as the integrated luminosity increases the relatively background-free but rate-limited same-sign dimuon, and ultimately the trimuon channel yield the highest reach. We show characteristic distributions in these channels that serve to distinguish the signal from the SM background, and also help to corroborate its SUSY origin. We then evaluate the LHC reach in various no-lepton and multi-lepton plus jets channels {\it including} missing ETE_T cuts for s=10\sqrt{s}=10 and 14 TeV, and plot the reach for integrated luminosities ranging up to 3000 fb−1^{-1} at the SLHC. For s=10\sqrt{s}=10 TeV, the LHC reach extends to mgluino=1.9,2.3,2.8m_{gluino}=1.9, 2.3, 2.8 and 2.9 TeV for msquark∼mgluinom_{squark}\sim m_{gluino} and integrated luminosities of 10, 100, 1000 and 3000 fb−1^{-1}, respectively. For s=14\sqrt{s}=14 TeV, the LHC reach for the same integrated luminosities is to m_{gluino}=2.4,\3.1, 3.7 and 4.0 TeV.Comment: 34 pages, 25 figures. Revised projections for the SUSY reach for ab^-1 integrated luminosities, with minor corrections of references and text. 2 figures added. To appear in JHE
    • …
    corecore