3,932 research outputs found

    Four units in mythology for use in English classes in grades eight and nine

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    Thesis (Ed.M.)--Boston University, 1948. This item was digitized by the Internet Archive

    Factors Leading to Effectiveness and Satisfaction in Civil Engineer Information Systems

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    The Air Force Civil Engineer Support Agency (AFCESA) has developed information systems in support of civil engineer operations. Over the last decade, the number of systems has grown to support the breadth of civil engineer functions. At this time, numerous (900+) decentralized systems support civil engineer functions around the world. Due to budget constraints, AFCESA is transforming civil engineer business processes to leverage the workforce in an optimized fashion. In support of this transition, AFCESA is posturing to acquire new information systems in support of civil engineer business processes. To help AFCESA improve upon its suite of information systems development efforts it is important to evaluate the effectiveness of its current systems. This thesis develops a model based on cumulative research to assess information system effectiveness. The thesis evaluates 10 systems developed for the civil engineer community. Predictors of information system effectiveness are System Quality, Information Quality, and Service Quality. The study indicates that one system, GeoBase, is significantly better in all areas of information system effectiveness. It is recommended that future system development be fashioned after GeoBase

    Power systems research at MSFC

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    Power systems research reviews at Marshall Space Flight Cente

    Weak turbulence theory of the non-linear evolution of the ion ring distribution

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    The nonlinear evolution of an ion ring instability in a low-beta magnetospheric plasma is considered. The evolution of the two-dimensional ring distribution is essentially quasilinear. Ignoring nonlinear processes the time-scale for the quasilinear evolution is the same as for the linear instability 1/t_ql gamma_l. However, when nonlinear processes become important, a new time scale becomes relevant to the wave saturation mechanism. Induced nonlinear scattering of the lower-hybrid waves by plasma electrons is the dominant nonlinearity relevant for plasmas in the inner magnetosphere and typically occurs on the timescale 1/t_ql w(M/m)W/nT, where W is the wave energy density, nT is the thermal energy density of the background plasma, and M/m is the ion to electron mass ratio, which has the consequence that the wave amplitude saturates at a low level, and the timescale for quasilinear relaxation is extended by orders of magnitude

    Unexpected Magnetism of Small Silver Clusters

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    The ground-state electronic, structural, and magnetic properties of small silver clusters, Agn_n (2\len\le22), have been studied using a linear combination of atomic Gaussian-type orbitals within the density functional theory. The results show that the silver atoms, which are diamagnetic in bulk environment, can be magnetic when they are grouped together in clusters. The Ag13_{13} cluster with icosahedral symmetry has the highest magnetic moment per atom among the studied silver clusters. The cluster symmetry and the reduced coordination number specific of small clusters reveal as a fundamental factor for the onset of the magnetism.Comment: 4 pages, 4 figure
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