8,626 research outputs found

    A NASTRAN model of a large flexible swing-wing bomber. Volume 3: NASTRAN model development-wing structure

    Get PDF
    The NASTRAN model plan for the wing structure was expanded in detail to generate the NASTRAN model for this substructure. The grid point coordinates were coded for each element. The material properties and sizing data for each element were specified. The wing substructure model was thoroughly checked out for continuity, connectivity, and constraints. This substructure was processed for structural influence coefficients (SIC) point loadings and the deflections were compared to those computed for the aircraft detail model. Finally, a demonstration and validation processing of this substructure was accomplished using the NASTRAN finite element program. The bulk data deck, stiffness matrices, and SIC output data were delivered

    A NASTRAN model of a large flexible swing-wing bomber. Volume 5: NASTRAN model development-fairing structure

    Get PDF
    The NASTRAN model plan for the fairing structure was expanded in detail to generate the NASTRAN model of this substructure. The grid point coordinates, element definitions, material properties, and sizing data for each element were specified. The fairing model was thoroughly checked out for continuity, connectivity, and constraints. The substructure was processed for structural influence coefficients (SIC) point loadings to determine the deflection characteristics of the fairing model. Finally, a demonstration and validation processing of this substructure was accomplished using the NASTRAN finite element program. The bulk data deck, stiffness matrices, and SIC output data were delivered

    Qualitative methods III: On different ways of describing our work

    Get PDF
    In two previous reviews, we examined how human geographers currently report on projects involving their preferred qualitative methods – interviews and ethnographic observation. This final review steps back from specific techniques to evaluate some of the broader presentational conventions that typify this work. What can be inferred from where these geographers discuss data collection in their papers? Why do they develop new methods and what do they say about fieldwork failures? How often do they reflect on the provisional status of their findings? And what are the implications of how they define their purpose in working with qualitative material

    On lenses and blind spots in qualitative exercise and environment research: A Response to Stephanie Coen

    Get PDF
    Qualitative research focused on how people experience the social and material environments in which they exercise has the potential to inform public health agendas in all sorts of ways. This commentary takes up the claim made by Stephanie Coen that such research should begin with an ‘equity lens’ and place a greater emphasis on ‘critique’ than we did in the ‘Exercise and Environment’ special issue to which she responds. At its best qualitative research reveals new ways of thinking about the social and material contexts at hand. As such, it has the potential to highlight important dimensions of the lived experience of popular fitness practices that may have hitherto been relatively overlooked. Always starting with the overt aim of applying an ‘equity lens’ truncates the possibility of discovering such dimensions. Furthermore, being too wedded to an overtly critical stance may end up hindering, rather than encouraging, the most positive dialogue between those studying the cotemporary exercise experience and those involved in public health

    Qualitative methods II: On the presentation of ‘geographical ethnography’

    Get PDF
    This review examines how ethnographic methods currently feature in the work of human geographers. The ethnographic approach continues to be a popular choice amongst those hoping to learn from how social life unfolds in particular places and settings. But what visions of ethnography do geographers draw on to attain authorial authority? What are the implications of how they present their field experiences? How, linking back to our last review, is their ethnographic work connected to the interview? And what are some of the downsides to how the term is deployed in the discipline

    Line Broadening in Field Metal-poor Red Giant and Red Horizontal Branch Stars

    Get PDF
    We report 349 radial velocities for 45 metal-poor field red giant and red horizontal branch stars. We have have identified one new spectroscopic binary, HD 4306, and one possible such system, HD 184711. We also report 57 radial velocities for 11 of the 91 stars reported on previously by Carney et al. (2003). As was found in the previous study, radial velocity "jitter" is present in many of the most luminous stars. Excluding stars showing spectroscopic binary orbital motion, all 7 of the red giants with M(V) <= -2.0 display jitter, as well as 3 of the 14 stars with -2.0 <= M(V) <= -1.4. We have also measured line broadening in all of the new spectra, using synthetic spectra as templates. The most luminous red giants show significant line broadening, as do many of the red horizontal branch stars, and we discuss briefly possible causes.Comment: To appear in the Astronomical Journa

    Remote sensing of vigor loss in conifers due to dwarf mistletoe

    Get PDF
    The initial operation of a multiband/multidate tower-tramway test site in northeastern Minnesota for the development of specifications for subsequent multiband aerial photography of more extensive study areas was completed. Multiband/multidate configurations suggested by the tower-tramway studies were and will be flown with local equipment over the Togo test site. This site was photographed by the NASA RB57F aircraft in August and September 1971. It appears that, of all the film/filter combinations attempted to date (including optical recombining of several spectral band images via photo enhancement techniques), Ektachrome infrared film with a Wratten 12 filter is the best for detecting dwarf mistletoe, and other tree diseases as well. Using this film/filter combination, infection centers are easily detectable even on the smallest photo scale (1:100,000) obtained on the Togo site

    Particle Dark Energy

    Full text link
    We explore the physics of a gas of particles interacting with a condensate that spontaneously breaks Lorentz invariance. The equation of state of this gas varies from 1/3 to less than -1 and can lead to the observed cosmic acceleration. The particles are always stable. In our particular class of models these particles are fermions with a chiral coupling to the condensate. They may behave as relativistic matter at early times, produce a brief period where they dominate the expansion with w<0 today, and behave as matter at late time. There are no small parameters in our models, which generically lead to dark energy clustering and, depending on the choice of parameters, smoothing of small scale power.Comment: 8 pages, 5 figures; minor update with added refs; version appearing in Phys. Rev.

    Heat capacity mapping mission project HCM-051

    Get PDF
    There are no author-identified significant results in this report
    • …
    corecore