420 research outputs found

    Automated data acquisition and reduction system for torsional braid analyzer

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    Automated Data Acquisition and Reduction System (ADAR) evaluates damping coefficient and relative rigidity by storing four successive peaks of waveform and time period between two successive peaks. Damping coefficient and relative rigidity are then calculated and plotted against temperature or time in real time

    Wide area detection system: Conceptual design study

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    An integrated sensor for traffic surveillance on mainline sections of urban freeways is described. Applicable imaging and processor technology is surveyed and the functional requirements for the sensors and the conceptual design of the breadboard sensors are given. Parameters measured by the sensors include lane density, speed, and volume. The freeway image is also used for incident diagnosis

    Resource Adequacy: Should Regulators Worry?

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    Regulators have proposed various institutional alternatives to secure network resource adequacy and reasonably priced electric power for consumers. These alternatives prompt many difficult questions: Does the development of Demand Response reduce the need for new capacity? How effectively can a government-mandated Capacity Market foster efficient investment? How does centralized generator commitment (with revenue guarantees) compare to a system in which Generators voluntarily commit themselves with no revenue guarantees? If exclusive distribution contracts were replaced by unregulated retail competition, what would be the effects on investment and market prices? We use laboratory experiments to address these questions

    Endopolyploidy Changes with Age-Related Polyethism in the Honey Bee, Apis mellifera

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    Honey bees (Apis mellifera) exhibit age polyethism, whereby female workers assume increasingly complex colony tasks as they age. While changes in DNA methylation accompany age polyethism, other DNA modifications accompanying age polyethism are less known. Changes in endopolyploidy (DNA amplification in the absence of cell division) with increased larval age are typical in many insect cells and are essential in adults for creating larger cells, more copies of essential loci, or greater storage capacity in secretory cells. However, changes in endopolyploidy with increased adult worker age and polyethism are unstudied. In this study, we examined endopolyploidy in honey bee workers ranging in age from newly emerged up to 55 days old. We found a nonsignificant increase in ploidy levels with age (P < 0.1) in the most highly endopolyploid secretory cells, the Malpighian tubules. All other cell types decreased ploidy levels with age. Endopolyploidy decreased the least amount (nonsignificant) in neural (brain) cells and the stinger (P < 0.1). There was a significant reduction of endopolyploidy with age in leg (P < 0.05) and thoracic (P < 0.001) muscles. Ploidy in thoracic muscle dropped from an average of 0.5 rounds of replication in newly emerged workers to essentially no rounds of replication (0.125) in the oldest workers. Ploidy reduction in flight muscle cells is likely due to the production of G1 (2C) nuclei by amitotic division in the multinucleate striated flight muscles that are essential to foragers, the oldest workers. We suggest that ploidy is constrained by the shape, size and makeup of the multinucleate striated muscle cells. Furthermore, the presence of multiple 2C nuclei might be optimal for cell function, while higher ploidy levels might be a dead-end strategy of some aging adult tissues, likely used to increase cell size and storage capacity in secretory cells.The open access fee for this work was funded through the Texas A&M University Open Access to Knowledge (OAK) Fund

    Induction heating coupler and annealer

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    An induction heating device includes a handle having a hollow interior and two opposite ends, a wrist connected to one end of the handle, a U-shaped pole piece having- two spaced apart ends, a tank circuit including an induction coil wrapped around the pole piece and a capacitor connected to the induction coil, a head connected to the wrist and including a housing for receiving the U-shaped pole piece, the two spaced apart ends of the pole piece extending outwardly beyond the housing, and a power source connected to the tank circuit. When the tank circuit is energized and a susceptor is placed in juxtaposition to the ends of the U-shaped pole piece, the susceptor is heated by induction heating due to a magnetic flux passing between the two ends of the pole piece

    Induction heating coupler

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    An induction heating device includes a handle having a hollow interior and two opposite ends, a wrist connected to one end of the handle, a U-shaped pole piece having two spaced apart ends, a tank circuit including an induction coil wrapped around the pole piece and a capacitor connected to the induction coil, a head connected to the wrist and including a housing for receiving the U-shaped pole piece, the two spaced apart ends of the pole piece extending outwardely beyond the housing, and a power source connected to the tank circuit. When the tank circuit is energized and a susceptor is placed in juxtaposition to the ends of the U-shaped pole piece, the susceptor is heated by induction heating due to magnetic flux passing between the two ends of the pole piece

    LSST Cadence Optimization White Paper in Support of Observations of Unresolved Tidal Stellar Streams in Galaxies beyond the Local Group

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    Deep observations of faint surface brightness stellar tidal streams in external galaxies with LSST are addressed in this White Paper contribution. We propose using the Wide--Fast--Deep survey that contains several nearby galaxies (at distances where the stars themselves are not resolved, i.e., beyond 20 Mpc). In the context of hierarchical galaxy formation, it is necessary to understand the prevalence and properties of tidal substructure around external galaxies based on integrated (i.e., unresolved) diffuse light. This requires collecting observations on much larger samples of galaxies than the Milky Way and M31. We will compare the observed structures to the predictions of cosmological models of galactic halo formation that inform us about the number and properties of streams around Milky Way-like galaxies. The insight gained from these comparisons will allow us to infer the properties of stream progenitors (masses, dynamics, metallicities, stellar populations). The changes in the host galaxies caused by the interactions with the dissolving companion galaxies will be another focus of our studies. We conclude by discussing synergies with WFIRST and Euclid, and also provide concrete suggestions for how the effects of scattered light could be minimized in LSST images to optimize the search for low surface brightness features, such as faint unresolved stellar tidal streams.Comment: 13 pages, 2 figures, submitted to Call for White Papers on LSST Cadence Optimizatio

    Exile Vol. XLII No. 1

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    40th Year Title Page by Sakura Yamamoto \u2797 i Epigraph by Ezra Pound ii Table of Contents iii / Untitled (artwork) by Gretchen Hambly \u2796 iv Breughel Again, Brussels by Adrienne Fair \u2796 1 for play with whitman by alex e blazer \u2797 4 Saeta Sunday by Carl Boon \u2796 5 An Abbreviated Life by Mike Westmoreland 6 Anthem of Governor\u27s Bay by Jamey Hein \u2796 7-10 Time is everywhere, yet nowhere (artwork) by Susanne Ducker \u2796 11 Crosses by Liz Bolyard \u2796 12 Raccoons at the Cats\u27 Food by Jennifer Rudgers \u2796 13-14 Father Federico by Trish Klei \u2797 15 Dream Poem I by Colin Bossen \u2798 16 Virgin Mary in Kentucky by Amy Ard \u2796 17 the jig is up by alex e blazer \u2797 18-20 Visiting Uncle Ernie by Liz Bolyard \u2796 21-22 A Capuchin Monk by Linda Fuller-Smith 23 Sunday, October 15, 1995 by Carl Boon \u2796 24 Old Man and the Marriage Party by Trish Klei \u2797 25 Untitled (artwork) by Gretchen Hambly \u2796 26 Cowboy Up by J. Murdoch Be Matheson \u2796 27-34 Fragments by Colin Bossen \u2798 35 meditation (artwork) by alex e blazer \u2797 36 Palazzo Rezzonico by Linda Fuller-Smith 37 A Poem About The Photographic Imprint I Would Leave If A Nuclear Bomb Hit Nearby As I Took Out The Trash One Night by Trish Klei \u2797 38 The Crazies I\u27ve Called by Julie Johnston \u2796 39-46 Contributors\u27 Notes 47-48 Editorial Board 49 Editorial decisions are shared equally among the Editorial Board. -49 Cover art by alex emmons -4

    Taking the Measure of the Universe: Precision Astrometry with SIM PlanetQuest

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    Precision astrometry at microarcsecond accuracy has application to a wide range of astrophysical problems. This paper is a study of the science questions that can be addressed using an instrument that delivers parallaxes at about 4 microarcsec on targets as faint as V = 20, differential accuracy of 0.6 microarcsec on bright targets, and with flexible scheduling. The science topics are drawn primarily from the Team Key Projects, selected in 2000, for the Space Interferometry Mission PlanetQuest (SIM PlanetQuest). We use the capabilities of this mission to illustrate the importance of the next level of astrometric precision in modern astrophysics. SIM PlanetQuest is currently in the detailed design phase, having completed all of the enabling technologies needed for the flight instrument in 2005. It will be the first space-based long baseline Michelson interferometer designed for precision astrometry. SIM will contribute strongly to many astronomical fields including stellar and galactic astrophysics, planetary systems around nearby stars, and the study of quasar and AGN nuclei. SIM will search for planets with masses as small as an Earth orbiting in the `habitable zone' around the nearest stars using differential astrometry, and could discover many dozen if Earth-like planets are common. It will be the most capable instrument for detecting planets around young stars, thereby providing insights into how planetary systems are born and how they evolve with time. SIM will observe significant numbers of very high- and low-mass stars, providing stellar masses to 1%, the accuracy needed to challenge physical models. Using precision proper motion measurements, SIM will probe the galactic mass distribution and the formation and evolution of the Galactic halo. (abridged)Comment: 54 pages, 28 figures, uses emulateapj. Submitted to PAS
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