5,078 research outputs found

    Digital curation and the cloud

    Get PDF
    Digital curation involves a wide range of activities, many of which could benefit from cloud deployment to a greater or lesser extent. These range from infrequent, resource-intensive tasks which benefit from the ability to rapidly provision resources to day-to-day collaborative activities which can be facilitated by networked cloud services. Associated benefits are offset by risks such as loss of data or service level, legal and governance incompatibilities and transfer bottlenecks. There is considerable variability across both risks and benefits according to the service and deployment models being adopted and the context in which activities are performed. Some risks, such as legal liabilities, are mitigated by the use of alternative, e.g., private cloud models, but this is typically at the expense of benefits such as resource elasticity and economies of scale. Infrastructure as a Service model may provide a basis on which more specialised software services may be provided. There is considerable work to be done in helping institutions understand the cloud and its associated costs, risks and benefits, and how these compare to their current working methods, in order that the most beneficial uses of cloud technologies may be identified. Specific proposals, echoing recent work coordinated by EPSRC and JISC are the development of advisory, costing and brokering services to facilitate appropriate cloud deployments, the exploration of opportunities for certifying or accrediting cloud preservation providers, and the targeted publicity of outputs from pilot studies to the full range of stakeholders within the curation lifecycle, including data creators and owners, repositories, institutional IT support professionals and senior manager

    Using an ontology for interoperability and browsing of museum, library and archive information

    No full text
    Ontologies play an important part in the development of the future ‘semantic web’; the CIDOC conceptual reference model (CRM) is an ontology aimed at the cultural heritage domain. This paper describes a Concept Browser, developed for the EU/IST-funded SCULPTEUR project (semantic and content-based multimedia exploitation for European benefit environment (programme IST-2001-no. 35372); May 2002 to May 2005), which is able to access different museum information systems through a common ontology, the CRM. The development of this Concept Browser has required mappings from the legacy museum database systems to the CRM. The crucial process of creating the mappings is described, using the C2RMF catalogue (EROS) and library databases as a case study

    A collaborative approach to embedding academic literacies in first year grant projects

    Full text link
    This paper describes the collaborative approach that Academic Language and Learning developers are using as part of a university’s First Year Experience project. This project draws on the idea of a third generation approach which utilises a bottom-up and top-down institutional framework. Intrinsic to this framework at UTS is a small grant scheme devised to support academics in designing curricula which facilitate first year students’ transition. However, smooth transition can be affected by the academic and linguistic capital of the increasingly diverse student population. This has provided the opportunity for ALL developers to become active participants in the small grant scheme and to work collaboratively with academics on the seamless integration of domain specific academic literacy. Two case studies of FYE grants illustrate the parameters and benefits of such an approach and how it may enable a discursive space to support sustainable practice

    High Resolution Millimeter-Wave Mapping of Linearly Polarized Dust Emission: Magnetic Field Structure in Orion

    Get PDF
    We present 1.3 and 3.3 mm polarization maps of Orion-KL obtained with the BIMA array at approximately 4 arcsec resolution. Thermal emission from magnetically aligned dust grains produces the polarization. Along the Orion ``ridge'' the polarization position angle varies smoothly from about 10 degrees to 40 degrees, in agreement with previous lower resolution maps. In a small region south of the Orion ``hot core,'' however, the position angle changes by 90 degrees. This abrupt change in polarization direction is not necessarily the signpost of a twisted magnetic field. Rather, in this localized region processes other than the usual Davis-Greenstein mechanism might align the dust grains with their long axes parallel with the field, orthogonal to their normal orientation.Comment: AAS preprint:14 pages, 2 figures (3mm.eps and 1mm.eps); requires aaspp4.sty To be published in Astrophysical Journal Letter

    The solid-state structures of cyclic NH carboximides

    Get PDF
    The patterns adopted in the solid state structures of over 300 cyclic NH carboximides as determined by X-ray diffraction are reviewed. While the analysis shows that the majority of these fit into just a few common patterns, a significant number exhibit more complex and interesting patterns involving the other functional groups present in addition to the cyclic imide.Publisher PDFPeer reviewe

    Impact ionization coefficients in strained InGaAs/InAlAs multiquantum wells

    Full text link
    We have measured electron and hole impact ionization coefficients in biaxially strained InxGa1−xAs/InyAl1−yAs (0.44≀x≀0.62, 0.44≀y≀0.62) multiquantum wells for the first time. It is seen that ÎČ/α is enhanced due to strain‐induced changes in band gap, band offsets, and bandstructure for tensile strain in the well and compressive strain in the barrier. The results have been interpreted by considering band‐to‐band impact ionization and band‐edge discontinuity impact ionization processes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70145/2/JAPIAU-73-10-5014-1.pd

    Measurement of Resonant Frequency and Quality Factor of Microwave Resonators: Comparison of Methods

    Full text link
    Precise microwave measurements of sample conductivity, dielectric, and magnetic properties are routinely performed with cavity perturbation measurements. These methods require the accurate determination of quality factor and resonant frequency of microwave resonators. Seven different methods to determine the resonant frequency and quality factor from complex transmission coefficient data are discussed and compared to find which is most accurate and precise when tested using identical data. We find that the nonlinear least-squares fit to the phase vs. frequency is the most accurate and precise when the signal-to-noise ratio is greater than 65. For noisier data, the nonlinear least squares fit to a Lorentzian curve is more accurate and precise. The results are general and can be applied to the analysis of many kinds of resonant phenomena.Comment: 29 pages, 11 figure

    Polarization of Thermal Emission from Aligned Dust Grains Under an Anisotropic Radiation Field

    Get PDF
    If aspherical dust grains are immersed in an anisotropic radiation field, their temperature depends on the cross-sections projected in the direction of the anisotropy.It was shown that the temperature difference produces polarized thermal emission even without alignment, if the observer looks at the grains from a direction different from the anisotropic radiation. When the dust grains are aligned, the anisotropy in the radiation makes various effects on the polarization of the thermal emission, depending on the relative angle between the anisotropy and alignment directions. If the both directions are parallel, the anisotropy produces a steep increase in the polarization degree at short wavelengths. If they are perpendicular, the polarization reversal occurs at a wavelength shorter than the emission peak. The effect of the anisotropic radiation will make a change of more than a few % in the polarization degree for short wavelengths and the effect must be taken into account in the interpretation of the polarization in the thermal emission. The anisotropy in the radiation field produces a strong spectral dependence of the polarization degree and position angle, which is not seen under isotropic radiation. The dependence changes with the grain shape to a detectable level and thus it will provide a new tool to investigate the shape of dust grains. This paper presents examples of numerical calculations of the effects and demonstrates the importance of anisotropic radiation field on the polarized thermal emission.Comment: 13pages, 7figure
    • 

    corecore