12,062 research outputs found

    Thermocouple installation

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    A thermocouple assembly which includes a plug having a pair of small diameter holes near one end thereof which are spaced a small distance apart to leave a thin quantity of plug material between the holes is presented. There are a pair of thermocouple wires extending through the different holes and with the outer ends of the wires joined to the thin quantity of plug material which lies between the holes to form a thermocouple junction

    Electoral Margins and American Foreign Policy 1

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/100173/1/isqu12040.pd

    Radial honeycomb core

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    Core alleviates many limitations of conventional nacelle construction methods. Radical core, made of metals or nonmetals, is fabricated either by joining nodes and then expanding, or by performing each layer and then joining nodes. Core may also be produced from ribbons or strips with joined nodes or ribbons oriented in longitudinal planes

    Confidence Level and Sensitivity Limits in High Contrast Imaging

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    In long adaptive optics corrected exposures, exoplanet detections are currently limited by speckle noise originating from the telescope and instrument optics, and it is expected that such noise will also limit future high-contrast imaging instruments for both ground and space-based telescopes. Previous theoretical analysis have shown that the time intensity variations of a single speckle follows a modified Rician. It is first demonstrated here that for a circular pupil this temporal intensity distribution also represents the speckle spatial intensity distribution at a fix separation from the point spread function center; this fact is demonstrated using numerical simulations for coronagraphic and non-coronagraphic data. The real statistical distribution of the noise needs to be taken into account explicitly when selecting a detection threshold appropriate for some desired confidence level. In this paper, a technique is described to obtain the pixel intensity distribution of an image and its corresponding confidence level as a function of the detection threshold. Using numerical simulations, it is shown that in the presence of speckles noise, a detection threshold up to three times higher is required to obtain a confidence level equivalent to that at 5sigma for Gaussian noise. The technique is then tested using TRIDENT CFHT and angular differential imaging NIRI Gemini adaptive optics data. It is found that the angular differential imaging technique produces quasi-Gaussian residuals, a remarkable result compared to classical adaptive optic imaging. A power-law is finally derived to predict the 1-3*10^-7 confidence level detection threshold when averaging a partially correlated non-Gaussian noise.Comment: 29 pages, 13 figures, accepted to Ap

    In democracies an effective media and opposition are both needed to sanction leaders’ foreign policy missteps

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    Common wisdom in international affairs is that when democratically elected leaders and governments make threats towards other states, these are credible; voters will punish leaders who do not follow through on their words. New research by Philip B. K. Potter and Matthew A. Baum argues however, that not all democracies are equal in the credibility of their threats of military action. By analyzing data on international military disputes over a 35-year period, they find that both an effective and widespread media, and a robust opposition are needed in order for voters to become aware of foreign policy blunders. Without either of these, leaders can avoid following through on their threats with little fear of being punished by voters

    Prevalence of and risk factors for acute laminitis in horses treated with corticosteroids

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    A retrospective treated versus untreated study (study 1) and multicentre prospective cohort study (study 2) were undertaken to determine the prevalence of, and risk factors associated with, acute laminitis in horses treated with corticosteroids. All old treated with corticosteroids January–December 2014 (study 1) and January 2015–February 2017 (study 2) by two first opinion and referral hospitals in UK were included. Additionally, an untreated animal was identified for each treated animal (study one). Signalment, body condition (study 2 only), relevant medical history, primary condition, corticosteroid therapy prescribed and occurrence of acute laminitis during or within 14 days of cessation of corticosteroid treatment were recorded. For study 1, 205 cases and 205 controls were identified; two animals within each group (1 per cent) developed laminitis. In total, 1565 animals were included in study 2; laminitis period prevalence was 0.6 per cent (95 per cent CI 0.4 per cent to 1.2 per cent), with 10 cases in 1565 treated animals. There were significant associations between laminitis and breed (pony vs horse; p=0.01; univariable analysis only), the presence of a laminitis risk factor (history of laminitis or an underlying endocrinopathy; p<0.001; OR (95 per cent CI) 18.23 (5.05 to 65.87)) and body condition (overweight/obese vs not; p=0.04; OR (95 per cent CI) 4.0 (1.09 to 14.75))

    The effect of two-temperature post-shock accretion flow on the linear polarization pulse in magnetic cataclysmic variables

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    The temperatures of electrons and ions in the post-shock accretion region of a magnetic cataclysmic variable (mCV) will be equal at sufficiently high mass flow rates or for sufficiently weak magnetic fields. At lower mass flow rates or in stronger magnetic fields, efficient cyclotron cooling will cool the electrons faster than the electrons can cool the ions and a two-temperature flow will result. Here we investigate the differences in polarized radiation expected from mCV post-shock accretion columns modeled with one- and two-temperature hydrodynamics. In an mCV model with one accretion region, a magnetic field >~30 MG and a specific mass flow rate of ~0.5 g/cm/cm/s, along with a relatively generic geometric orientation of the system, we find that in the ultraviolet either a single linear polarization pulse per binary orbit or two pulses per binary orbit can be expected, depending on the accretion column hydrodynamic structure (one- or two-temperature) modeled. Under conditions where the physical flow is two-temperature, one pulse per orbit is predicted from a single accretion region where a one-temperature model predicts two pulses. The intensity light curves show similar pulse behavior but there is very little difference between the circular polarization predictions of one- and two-temperature models. Such discrepancies indicate that it is important to model some aspect of two-temperature flow in indirect imaging procedures, like Stokes imaging, especially at the edges of extended accretion regions, were the specific mass flow is low, and especially for ultraviolet data.Comment: Accepted for publication in Astrophysics & Space Scienc

    Proton Losses Upstream of IP8 in LHC

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    In this report we analyse possible distant sources of proton losses in the long straight section around IP8. These sources can be collisions of the beam protons with nuclei of residual gas in the arcs, betatron cleaning inefficiency and proton-proton collisions in IR1

    Imaging Polarimetric Observations of a New Circumstellar Disk System

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    Few circumstellar disks have been directly observed. Here we use sensitive differential polarimetric techniques to overcome atmospheric speckle noise in order to image the circumstellar material around HD 169142. The detected envelope or disk is considerably smaller than expectations based on the measured strength of the far-IR excess from this system
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