67 research outputs found

    Feasibility test for a V-slit star mapper for pioneer spacecraft terminal navigation

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    A laboratory demonstration of the feasibility of using a V-slit star mapper to meet the sensitivity and accuracy of on-board navigational requirements for future Pioneer Missions to the outer planets was conducted by the Control and Sensors Laboratory of TRW. The breadboard was extremely simple in configuration, consisting of an end-on photomultiplier tube and a V-slit reticle located at the focal plane of the objective lens. In addition, a plano-convex lens was used between the reticle and the PMT in a Fabry-Perot configuration. The analytical effort indicated that the sensor should easily meet the requirements. The Pioneer SRA test set was examined to determine its basic accuracy and modify it where necessary to bring its accuracy into the 1-3 arc second range. The test results show that it is feasible to use this type of star mapper in the 10 arc second accuracy range. The test equipment accuracy (approximately 5 arc Sec) was sufficient to bound the sensor errors at less than 10 arc seconds

    The Application of Archival Concepts to a Data-Intensive Environment: Working with Scientists to Understand Data Management and Preservation Needs

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    The collection, organization, and long-term preservation of resources are the raison d’ĂȘtre of archives and archivists. The archival community, however, has largely neglected science data, assuming they were outside the bounds of their professional concerns. Scientists, on the other hand, increasingly recognize that they lack the skills and expertise needed to meet the demands being placed on them with regard to data curation and are seeking the help of “data archivists” and “data curators.” This represents a significant opportunity for archivists and archival scholars but one that can only be realized if they better understand the scientific context.National Science Foundation under Grant No. 0724300Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86738/1/Akmonetal2011.pd

    Planetary magnetic fields

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    A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America, and the Biogeography of Neoceratopsia

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    Competing interests: Andrew A. Farke has read the journal's policy and the authors of this manuscript have the following competing interests: Andrew A. Farke is a volunteer section editor and academic editor for PLOS ONE. This does not alter the authors' adherence to PLOS ONE policies on sharing data and materials.Acknowledgments It is a pleasure to offer our most heartfelt thanks to Scott K. Madsen, who found OMNH 34557 and prepared it with consummate skill. We are grateful to James Taylor, Jack Owen, the Keebler family, and the Montana Bureau of Land Management for access to outcrops of the Cloverly Formation. We thank Xu Xing (IVPP) and Hai-Lu You (formerly CAGS-IG) for facilitating access to specimens, Mark Loewen, Joseph Frederickson, Darren Naish, and Leonardo Maiorino for productive discussion and comments, and Roger Burkhalter for assistance in photography. Gary Wisser, from the scientific visualization center at Western University of Health Sciences, is gratefully acknowledged for the high resolution scan of the cranium. Reviews by Peter Makovicky, Hai-Lu You, and editor Peter Wilf improved the manuscript.Author Contributions Conceived and designed the experiments: AAF WDM RLC. Performed the experiments: AAF WDM RLC. Analyzed the data: AAF WDM RLC MJW. Contributed reagents/materials/analysis tools: AAF WDM RLC MJW. Wrote the paper: AAF WDM RLC MJW.The fossil record for neoceratopsian (horned) dinosaurs in the Lower Cretaceous of North America primarily comprises isolated teeth and postcrania of limited taxonomic resolution, hampering previous efforts to reconstruct the early evolution of this group in North America. An associated cranium and lower jaw from the Cloverly Formation (?middle–late Albian, between 104 and 109 million years old) of southern Montana is designated as the holotype for Aquilops americanus gen. et sp. nov. Aquilops americanus is distinguished by several autapomorphies, including a strongly hooked rostral bone with a midline boss and an elongate and sharply pointed antorbital fossa. The skull in the only known specimen is comparatively small, measuring 84 mm between the tips of the rostral and jugal. The taxon is interpreted as a basal neoceratopsian closely related to Early Cretaceous Asian taxa, such as Liaoceratops and Auroraceratops. Biogeographically, A. americanus probably originated via a dispersal from Asia into North America; the exact route of this dispersal is ambiguous, although a Beringian rather than European route seems more likely in light of the absence of ceratopsians in the Early Cretaceous of Europe. Other amniote clades show similar biogeographic patterns, supporting an intercontinental migratory event between Asia and North America during the late Early Cretaceous. The temporal and geographic distribution of Upper Cretaceous neoceratopsians (leptoceratopsids and ceratopsoids) suggests at least intermittent connections between North America and Asia through the early Late Cretaceous, likely followed by an interval of isolation and finally reconnection during the latest Cretaceous.Funding was received from the National Science Foundation (DEB 9401094, 9870173, http://www.nsf.gov); National Geographic Society (5918-97, http://www.nationalgeographic.com/); and American Chemical Society (PRF #38572-AC8, http://www.acs.org). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Yeshttp://www.plosone.org/static/editorial#pee

    Supporting Biological Information Work: Research and Education for Digital Resources and Long-lived Data

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    New practices are emerging in all stages of biological research, from data collection through dissemination of results. In addition, libraries and museums are increasingly being called upon to become the long-term curators and stewards of the range of intellectual products and research data. Through a series of cooperative projects with biologists working in data-intensive and informatics-based domains, we have documented requirements for digital libraries, tool development, and data management techniques to support contemporary scientific practice. This research is now serving as the foundation for a new biological informatics master's program designed to train a new generation of Library and Information Science professionals to serve in scientific research environments. To respond to the qualitative changes in biological research and the specific workforce gaps identified in our research, we are developing this program as part of a campus-wide bioinformatics initiative at the University of Illinois at Urbana-Champaign. By providing access to experts from across the University who specialize in many areas of biology and information management, the program will train a new generation of Library and Information Science professionals to serve in scientific research environments.NSF-0222848NSF-IIS-0534567published or submitted for publicationnot peer reviewe

    Charles T. Cragin, ca. 1907

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    Black and white photograph (dated ca. 1907) of penman Charles T. Cragin. The back of the photograph shows Cragin's signature
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