38 research outputs found

    Integrated System Health Management (ISHM) Technology Demonstration Project Final Report

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    Integrated System Health Management (ISHM) is an essential capability that will be required to enable upcoming explorations mission systems such as the Crew Exploration Vehicle (CEV) and Crew Launch Vehicle (CLV), as well as NASA aeronautics missions. However, the lack of flight experience and available test platforms have held back the infusion by NASA Ames Research Center (ARC) and the Jet Propulsion Laboratory (JPL) of ISHM technologies into future space and aeronautical missions. To address this problem, a pioneer project was conceived to use a high-performance aircraft as a low-cost proxy to develop, mature, and verify the effectiveness of candidate ISHM technologies. Given the similarities between spacecraft and aircraft, an F/A-18 currently stationed at Dryden Flight Research Center (DFRC) was chosen as a suitable host platform for the test bed. This report describes how the test bed was conceived, how the technologies were integrated on to the aircraft, and how these technologies were matured during the project. It also describes the lessons learned during the project and a forward path for continued work

    Young children's interpersonal trust consistency as a predictor of future school adjustment

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    Young children’s interpersonal trust consistency was examined as a predictor of future school adjustment. One hundred and ninety two (95 male and 97 female, M age = 6 years 2 months, SD age = 6 months) children from school years 1 and 2 in the United Kingdom were tested twice over one-year. Children completed measures of peer trust and school adjustment and teachers completed the Short-Form Teacher Rating Scale of School Adjustment. Longitudinal quadratic relationships emerged between consistency of children’s peer trust beliefs and peer-reported trustworthiness and school adjustment and these varied according to social group, facet of trust, and indictor of school adjustment. The findings support the conclusion that interpersonal trust consistency, especially for secret-keeping, predicts aspects of young children’s school adjustment

    The WAIS Divide deep ice core WD2014 chronology - Part 2: Annual-layer counting (0-31 ka BP)

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    International audienceWe present the WD2014 chronology for the upper part (0–2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposi-tion of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cos-mogenic isotope records of 10 Be from WAIS Divide and 14 C for IntCal13 demonstrated that WD2014 was consistently accurate to better than 0.5 % of the age. For the glacial period, comparisons to the Hulu Cave chronology demonstrated that WD2014 had an accuracy of better than 1 % of the age at three abrupt climate change events between 27 and 31 ka. WD2014 has consistently younger ages than Green-land ice core chronologies during most of the Holocene. For Published by Copernicus Publications on behalf of the European Geosciences Union. 770 M. Sigl et al.: The WAIS Divide deep ice core WD2014 chronology the Younger Dryas–Preboreal transition (11.595 ka; 24 years younger) and the Bþlling–Allerþd Warming (14.621 ka; 7 years younger), WD2014 ages are within the combined uncertainties of the timescales. Given its high accuracy, WD2014 can become a reference chronology for the Southern Hemisphere, with synchronization to other chronologies feasible using high-quality proxies of volcanism, solar activity , atmospheric mineral dust, and atmospheric methane concentrations

    The SPARC Toroidal Field Model Coil Program

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    The SPARC Toroidal Field Model Coil (TFMC) Program was a three-year effort between 2018 and 2021 that developed novel Rare Earth Yttrium Barium Copper Oxide (REBCO) superconductor technologies and then successfully utilized these technologies to design, build, and test a first-in-class, high-field (~20 T), representative-scale (~3 m) superconducting toroidal field coil. With the principal objective of demonstrating mature, large-scale, REBCO magnets, the project was executed jointly by the MIT Plasma Science and Fusion Center (PSFC) and Commonwealth Fusion Systems (CFS). The TFMC achieved its programmatic goal of experimentally demonstrating a large-scale high-field REBCO magnet, achieving 20.1 T peak field-on-conductor with 40.5 kA of terminal current, 815 kN/m of Lorentz loading on the REBCO stacks, and almost 1 GPa of mechanical stress accommodated by the structural case. Fifteen internal demountable pancake-to-pancake joints operated in the 0.5 to 2.0 nOhm range at 20 K and in magnetic fields up to 12 T. The DC and AC electromagnetic performance of the magnet, predicted by new advances in high-fidelity computational models, was confirmed in two test campaigns while the massively parallel, single-pass, pressure-vessel style coolant scheme capable of large heat removal was validated. The REBCO current lead and feeder system was experimentally qualified up to 50 kA, and the crycooler based cryogenic system provided 600 W of cooling power at 20 K with mass flow rates up to 70 g/s at a maximum design pressure of 20 bar-a for the test campaigns. Finally, the feasibility of using passive, self-protection against a quench in a fusion-scale NI TF coil was experimentally assessed with an intentional open-circuit quench at 31.5 kA terminal current.Comment: 17 pages 9 figures, overview paper and the first of a six-part series of papers covering the TFMC Progra

    The SPARC Toroidal Field Model Coil Program

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    Prosodic structure and suprasegmental features:Short-vowel stĂžd in Danish

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    This paper presents a phonological analysis of a glottalization phenomenon in dialects of Danish known as ‘short-vowel stþd’. It is argued that both short-vowel stþd and common Danish stþd involve the attachment of a laryngeal feature to a prosodic node—specifically the mora. In the case of short-vowel stþd that mora lacks segmental content, as it is projected top-down due to local prosodic requirements, not bottom-up by segmental material. I show that this device provides an account of the distribution of short-vowel stþd as arising from the interplay of constraints on metrical structure (both lexically stored and computed by the grammar) and the requirement for morae to be featurally licensed. The analysis provides further evidence for the analysis of ‘tonal accents’ and related phenomena in terms of metrical structure rather than lexical tone or laryngeal features, and contributes to our understanding of the relationship between segmental and suprasegmental phonology in Germanic languages

    Observing children\u27s playground activity levels at 13 Illawarra primary schools using CAST2

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    Declining levels of children’s physical activity may contribute to Australia’s increasing childhood obesity epidemic. School recess is an underutilized opportunity to increase children’s physical activity. Methods: Thirteen regional Australian public primary schools participated in the study (2946 children). The Children’s Activity Scanning Tool 2 (CAST2) collected observational playground physical activity data. The research also addressed: length of break, socioeconomic status (SES), gender, number of scanning days, and instrument calibration. Results: The proportions of Moderate or Vigorous Physically Activity (MVPA) children at the observed schools ranged from 0.4 to 0.7. The odds ratio of boys being MVPA relative to girls ranged from 0.8581 to 2.137. There were significant differences between the mean proportions of 3 days of activity (range P = .001 to P = .015) and no association between SES school groupings (deviance ratio: 0.48; P = .503). Interrater reliability for instrument calibration using Spearman correlations coefficients ranged from r = .71 to r = .99. Conclusions: There were significant differences between proportions of MVPA children at the 13 schools and between male and female populations. There was no association between playground physical activity and SES. The monitoring period for CAST2 should be at least 3 days. Interrater reliability indicates that correlations between observers were consistently high

    Parts of arrays-an introduction

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    From a functional point of view: a framework for extensions to APL

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