591 research outputs found

    Vision inspection system and method

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    An optical vision inspection system (4) and method for multiplexed illuminating, viewing, analyzing and recording a range of characteristically different kinds of defects, depressions, and ridges in a selected material surface (7) with first and second alternating optical subsystems (20, 21) illuminating and sensing successive frames of the same material surface patch. To detect the different kinds of surface features including abrupt as well as gradual surface variations, correspondingly different kinds of lighting are applied in time-multiplexed fashion to the common surface area patches under observation

    Paper Session II-C - Optical Alignment Measurements of Space Shuttle Tiles

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    The Space Shuttles are serviced and maintained by the Lockheed Space Operations Company (LSOC) at the Kennedy Space Center in Florida. The tiles which act as a heat shield during Shuttle re-entry into the earth\u27s atmosphere, are a major part of the Shuttle servicing efforts. One very tedious and labor intensive task is the alignment measurement of these tiles. Alignment measurements include measuring the gaps, or separation between two adjacent tiles, and measuring the steps, or the height differences between adjacent tiles. Traditional methods of measurement required two mechanical tools to separately measure steps and gaps. Plastic feeler gauges were used for gap measurements and dial-indicator trammel tools were used to measure steps. The Lockheed Research And Development Division (R&DD) in Palo Alto, CA developed and built the hand-held optical tool, the Lockheed Laser Tool (LLT), that is currently being used to measure tile steps and gaps. The LLT measures both steps and gaps simultaneously, replacing both mechanical tools. Integration of the LLT into the Shuttle servicing environment and the formal certification and acceptance of its use was an important milestone for state-ofthe- art technology being utilized to improve and maintain Shuttle processing flow. This was an iterative process during a six month period in 1988. Direct feedback from Shuttle operations/engineering helped refine the user-interface and became a critical contribution to the success of the program

    Drug discovery: A jump-start for electroceuticals

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    Imagine a day when electrical impulses are a mainstay of medical treatment. Your clinician will administer electroceuticals that target individual nerve fibres or specific brain circuits to treat an array of conditions. These will modulate the neural impulses that control the body, repair lost function and reinstate a healthy balance. They could coax insulin from islet cells, regulate food intake, and control inflammation. They may treat pressing major ailments such as hypertension, diabetes, obesity, heart failure, pulmonary and vascular disease. All this is within reach, we argue, if researchers from disparate disciplines in academia and industry work together. We herewith outline what needs to be done to bring about electroceuticals, and unveil a public-private research initiative and award that aim to catalyse the field

    Variability Catalog of Stars Observed During the TESS Prime Mission

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    During its 2-year Prime Mission, TESS observed over 232,000 stars at a 2-min cadence across ~70% of the sky. These data provide a record of photometric variability across a range of astrophysically interesting time scales, probing stellar rotation, stellar binarity, and pulsations. We have analyzed the TESS 2-min light curves to identify periodic variability on timescales 0.01-13 days, and explored the results across various stellar properties. We have identified over 46,000 periodic variables with high confidence, and another 38,000 with moderate confidence. These light curves show differences in variability type across the HR diagram, with distinct groupings of rotational, eclipsing, and pulsational variables. We also see interesting patterns across period-luminosity space, with clear correlations between period and luminosity for high-mass pulsators, evolved stars, and contact binary systems, a discontinuity corresponding to the Kraft break, and a lower occurrence of periodic variability in main-sequence stars on timescales of 1.5 to 2 days. The variable stars identified in this work are cross-identified with several other variability catalogs, from which we find good agreement between the measured periods of variability. There are ~65,000 variable stars that are newly identified in this work, which includes rotation rates of low-mass stars, high-frequency pulsation periods for high-mass stars, and a variety of giant star variability.Comment: 29 pages, 17 figures, accepted to ApJS, catalog available: https://archive.stsci.edu/hlsp/tess-svc, data visualization tool: https://filtergraph.com/tessvariabilit

    Measuring the thermodynamic cost of timekeeping

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    All clocks, in some form or another, use the evolution of nature toward higher entropy states to quantify the passage of time. Because of the statistical nature of the second law and corresponding entropy flows, fluctuations fundamentally limit the performance of any clock. This suggests a deep relation between the increase in entropy and the quality of clock ticks. Indeed, minimal models for autonomous clocks in the quantum realm revealed that a linear relation can be derived, where for a limited regime every bit of entropy linearly increases the accuracy of quantum clocks. But can such a linear relation persist as we move toward a more classical system? We answer this in the affirmative by presenting the first experimental investigation of this thermodynamic relation in a nanoscale clock. We stochastically drive a nanometer-thick membrane and read out its displacement with a radio-frequency cavity, allowing us to identify the ticks of a clock. We show theoretically that the maximum possible accuracy for this classical clock is proportional to the entropy created per tick, similar to the known limit for a weakly coupled quantum clock but with a different proportionality constant. We measure both the accuracy and the entropy. Once nonthermal noise is accounted for, we find that there is a linear relation between accuracy and entropy and that the clock operates within an order of magnitude of the theoretical bound

    Examining Configural, Metric, and Scalar Invariance of the Pain Catastrophizing Scale In Native American and Non-Hispanic White Adults In the Oklahoma Study of Native American Pain Risk (OK-SNAP)

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    Introduction: Native Americans (NAs) have a higher prevalence of chronic pain than other US racial/ethnic groups, but the mechanisms contributing to this pain disparity are under-researched. Pain catastrophizing is one of the most important psychosocial predictors of negative pain outcomes, and the Pain Catastrophizing Scale (PCS) has been established as a reliable and valid measure of the pain catastrophizing construct. However, before the PCS can be used to study pain risk in NAs, it is prudent to first determine whether the established 3-factor structure of the PCS also holds true for NAs. Methods: The current study examined the measurement (configural, metric, and scalar) invariance of the PCS in a healthy, pain-free sample of 138 NA and 144 non-Hispanic white (NHW) participants. Results: Results suggest that the previously established 3-factor solution fits for both groups (configural invariance) and that the factor loadings were equivalent across groups (metric invariance). Scalar invariance was also established, except for 1 minor scalar difference in a single threshold for item 3 (suggesting NHWs were more likely to respond with a 4 on that item than NAs). Discussion: Results provide additional evidence for the psychometric properties of the PCS and suggest it can be used to study pain catastrophizing in healthy, pain-free NA samples

    The Lantern Vol. 5, No. 1, December 1936

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    • All of Us • Public Dance • In Tibet, of All Places • Thoughts • Subterranean Conflict on the Campus • Out, Out Into Fragrance and Sweetness • My Soul Steals Out to Meet You In the Night • Bored Young Lady • Guay Shin\u27s Prayer • On Playing Ping-Pong • The Love-Life of One Cat and the Death of Another • My Lady • Danger! Germs Working! • The Wolves • Letters from India • With Apologies to Hamlet • The Dreamhttps://digitalcommons.ursinus.edu/lantern/1015/thumbnail.jp

    The Lantern Vol. 5, No. 3, May 1937

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    • Dedication • Dr. McClure: An Ursinus Man • Roar, O Wind! • To the Ladies! • The Futility of Dying • The Symbolism of the British Crown • Oh! • It Might Have Been • Treat Yourself? • Three Writers • Hawaii in June • On Being a Twin • Black Magic • Triangle • Who Longs? • A Son Passes • Sing an Old-Fashioned Song • Questioning • An Argument About a Fish • That Morning Eye-Opener • Scoop for the Sun • The Dead Do Not Die Once • Give Us Timehttps://digitalcommons.ursinus.edu/lantern/1010/thumbnail.jp

    The Lantern Vol. 6, No. 1, December 1937

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    • After Thinking Things Over • Ho! Ho! The Mistletoe! • Unrealized Dreams • Two Preeminent Victorians • The Thing • Progression • It Wasn\u27t in the Lines • He Was the Most Perfect Man • College (C)lasses • Robins and Roses • The Commuter • When the Rose is Dead • Truth in Print • Alias Mike Romanoff • Winslow Homer • When I Was Young • Maurice Evans, a Great Shakespearean • Among Our Contributors • Of Manx and Man • A Sanguinary Pirate • Conversation Has an Adventure • Ursinus\u27 Neediest Casehttps://digitalcommons.ursinus.edu/lantern/1016/thumbnail.jp

    Planetary Candidates Observed by Kepler. VIII. A Fully Automated Catalog With Measured Completeness and Reliability Based on Data Release 25

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    We present the Kepler Object of Interest (KOI) catalog of transiting exoplanets based on searching four years of Kepler time series photometry (Data Release 25, Q1-Q17). The catalog contains 8054 KOIs of which 4034 are planet candidates with periods between 0.25 and 632 days. Of these candidates, 219 are new and include two in multi-planet systems (KOI-82.06 and KOI-2926.05), and ten high-reliability, terrestrial-size, habitable zone candidates. This catalog was created using a tool called the Robovetter which automatically vets the DR25 Threshold Crossing Events (TCEs, Twicken et al. 2016). The Robovetter also vetted simulated data sets and measured how well it was able to separate TCEs caused by noise from those caused by low signal-to-noise transits. We discusses the Robovetter and the metrics it uses to sort TCEs. For orbital periods less than 100 days the Robovetter completeness (the fraction of simulated transits that are determined to be planet candidates) across all observed stars is greater than 85%. For the same period range, the catalog reliability (the fraction of candidates that are not due to instrumental or stellar noise) is greater than 98%. However, for low signal-to-noise candidates between 200 and 500 days around FGK dwarf stars, the Robovetter is 76.7% complete and the catalog is 50.5% reliable. The KOI catalog, the transit fits and all of the simulated data used to characterize this catalog are available at the NASA Exoplanet Archive.Comment: 61 pages, 23 Figures, 9 Tables, Accepted to The Astrophysical Journal Supplement Serie
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