67 research outputs found

    In-Space Propulsion: Connectivity to In-Space Fabrication and Repair

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    The connectivity between new in-space propulsion technologies and the ultimate development of an in-space fabrication and repair infrastructure are described in this Technical Memorandum. A number of advanced in-space propulsion technologies are being developed by NASA, many of which are directly relevant to the establishment of such an in-space infrastructure. These include aerocapture, advanced solar-electric propulsion, solar-thermal propulsion, advanced chemical propulsion, tethers, and solar photon sails. Other, further-term technologies have also been studied to assess their utility to the development of such an infrastructure

    Ares I-X Flight Data Evaluation: Executive Overview

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    NASA's Constellation Program (CxP) successfully launched the Ares I-X flight test vehicle on October 28, 2009. The Ares I-X flight was a developmental flight test to demonstrate that this very large, long, and slender vehicle could be controlled successfully. The flight offered a unique opportunity for early engineering data to influence the design and development of the Ares I crew launch vehicle. As the primary customer for flight data from the Ares I-X mission, the Ares Projects Office (APO) established a set of 33 flight evaluation tasks to correlate flight results with prospective design assumptions and models. The flight evaluation tasks used Ares I-X data to partially validate tools and methodologies in technical disciplines that will ultimately influence the design and development of Ares I and future launch vehicles. Included within these tasks were direct comparisons of flight data with preflight predictions and post-flight assessments utilizing models and processes being applied to design and develop Ares I. The benefits of early development flight testing were made evident by results from these flight evaluation tasks. This overview provides summary information from assessment of the Ares I-X flight test data and represents a small subset of the detailed technical results. The Ares Projects Office published a 1,600-plus-page detailed technical report that documents the full set of results. This detailed report is subject to the International Traffic in Arms Regulations (ITAR) and is available in the Ares Projects Office archives files

    Young Children Learning Languages in a Multilingual Context

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    Luxembourg is a trilingual country where residents communicate in Luxembourgish, French and German concurrently. Children therefore study these languages at primary school. In this paper I explore how six eight-year-old Luxembourgish children use and learn German, French and English in formal and informal settings over a period of one year. Their eagerness to learn and use German and English contrasted with their cautious and formal approach to the learning of French. My findings demonstrate that second language learning in a multilingual country is not an 'automatic' or 'natural' process but, rather, children's language behaviour depends on their personal goals, interests, competence, confidence and understanding of what counts as appropriate language use. These factors are influenced by the formal approach to language learning at school
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