225 research outputs found

    Closing the Loop: Creating Deliverables That Add Value

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    As special collections librarians and liaison librarians work together to create in­novative experiences working with primary source material, it is important to remember students have much to offer in the collaborative design process. In this case study, Prudence Doherty, a special collections librarian, and Daniel DeSanto, an instruction librarian, describe a project they initiated and implemented with upper-level education majors at the University of Vermont (UVM). The students were pre-service teachers (student teachers working toward degree and licensure) enrolled in Social Education and Social Studies, a course that focuses on teaching methods, assessment alternatives, and resources used in the elementary (K–4) classroom. The project gave the pre-service teachers an opportunity to work with three digital collections in order to design lesson plans for elementary-aged stu­dents. The project closed the loop of learn, create, and teach by requiring students to learn evaluative approaches to working with historical material and then create lesson plans based on those approaches. By creating professional resources for other teachers, the students added value to the digital collections

    Statistical properties of spontaneous emission near a rough surface

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    We study the lifetime of the excited state of an atom or molecule near a plane surface with a given random surface roughness. In particular, we discuss the impact of the scattering of surface modes within the rough surface. Our study is completed by considering the lateral correlation length of the decay rate and the variance discussing its relation to the C0 correlation

    3-D Reconstructions and Numerical Simulations of Precarious Rocks in Southern California

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    Reliable estimates of seismic hazard are essential for the development of resilient communities; however, estimates of rare, yet high intensity earthquakes are highly uncertain due to a lack of observations and recordings. Lacking this data, seismic hazard analyses may be based on extrapolations from earthquakes with more moderate return periods, which can lead to physically unrealistic earthquake scenarios. However, the existence of certain precariously balanced rocks (PBRs) has been identified as an indicator of an upper bound ground motion, which precludes toppling of the balanced rock, over its lifetime. To this end, a survey of PBRs was conducted in proximity to the Elsinore fault east of San Diego, CA. Each identified PBR is modeled using point clouds derived from ground-based laser scanning and images from an unmanned aerial vehicle. The resultant geometric reconstructions are then used in a probabilistic overturning analysis and compared to the anticipated seismic hazard at the site. Accounting for an estimated age range and 50% probability of overturning for the PBRs, approximately half of the surveyed PBRs indicate a potential overestimation of seismic hazard at the site

    Discrimination between two mechanisms of surface-scattering in a single-mode waveguide

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    Transport properties of a single-mode waveguide with rough boundary are studied by discrimination between two mechanisms of surface scattering, the amplitude and square-gradient ones. Although these mechanisms are generically mixed, we show that for some profiles they can separately operate within non-overlapping intervals of wave numbers of scattering waves. This effect may be important in realistic situations due to inevitable long-range correlations in scattering profiles.Comment: 5 pages, 3 figure

    Features in the diffraction of a scalar plane wave from doubly-periodic Dirichlet and Neumann surfaces

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    The diffraction of a scalar plane wave from a doubly-periodic surface on which either the Dirichlet or Neumann boundary condition is imposed is studied by means of a rigorous numerical solution of the Rayleigh equation for the amplitudes of the diffracted Bragg beams. From the results of these calculations the diffraction efficiencies of several of the lowest order diffracted beams are calculated as functions of the polar and azimuthal angles of incidence. The angular dependencies of the diffraction efficiencies display features that can be identified as Rayleigh anomalies for both types of surfaces. In the case of a Neumann surface additional features are present that can be attributed to the existence of surface waves on such surfaces. Some of the results obtained through the use of the Rayleigh equation are validated by comparing them with results of a rigorous Green's function numerical calculation.Comment: 16 pages, 5 figure

    Explicit asymptotic modelling of transient Love waves propagated along a thin coating

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    The official published version can be obtained from the link below.An explicit asymptotic model for transient Love waves is derived from the exact equations of anti-plane elasticity. The perturbation procedure relies upon the slow decay of low-frequency Love waves to approximate the displacement field in the substrate by a power series in the depth coordinate. When appropriate decay conditions are imposed on the series, one obtains a model equation governing the displacement at the interface between the coating and the substrate. Unusually, the model equation contains a term with a pseudo-differential operator. This result is confirmed and interpreted by analysing the exact solution obtained by integral transforms. The performance of the derived model is illustrated by numerical examples.This work is sponsored by the grant from Higher Education of Pakistan and by the Brunel University’s “BRIEF” research award

    A new application of reduced Rayleigh equations to electromagnetic wave scattering by two-dimensional randomly rough surfaces

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    The small perturbations method has been extensively used for waves scattering by rough surfaces. The standard method developped by Rice is difficult to apply when we consider second and third order of scattered fields as a function of the surface height. Calculations can be greatly simplified with the use of reduced Rayleigh equations, because one of the unknown fields can be eliminated. We derive a new set of four reduced equations for the scattering amplitudes, which are applied to the cases of a rough conducting surface, and to a slab where one of the boundary is a rough surface. As in the one-dimensional case, numerical simulations show the appearance of enhanced backscattering for these structures.Comment: RevTeX 4 style, 38 pages, 16 figures, added references and comments on the satellites peak

    (In)dependência funcional na dependente relação de homens tetraplégicos com seus (in)substituíveis pais/cuidadores

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    Objetivou-se identificar elementos da classificação internacional de funcionalidade, incapacidade e saúde, aplicáveis ao cuidado domiciliar de homens adultos tetraplégicos, com vistas à redução da dependência de ajuda de seus pais para as atividades da vida diária, e o autocuidado. Os dados foram coletados de junho de 2004 a março de 2005, a partir de entrevista semi-estruturada, realizada com 8 adultos acometidos de lesão medular alta, e com experiência de usuários do cuidado domiciliar. Optou-se pela análise de conteúdo, a partir das categorias de significados pautadas nos seguintes resultados: suporte familiar: segurança para as funções corporais do incapacitado; tecnologia assistiva: inventividades para promoção da qualidade do cuidado; medos, futuro incerto e perda dos pais: limiares e fragilidades humanas; e ganhos funcionais: respostas objetivas das funções corporais. Conclui-se que o apoio da família e, em especial, a presença dos pais, são fundamentais para enfrentar as limitações e reagir na busca de equilíbrio na deficiência, incapacidade, desvantagem e saúde dessa clientela, preparando-a para o alcance de gradativos ganhos funcionais e independência para atividades cotidianas e autocuidado.El estudio tuvo como objetivo identificar elementos de la clasificación internacional de funcionalidad, incapacidad y salud, aplicables al cuidado domiciliario de hombres adultos cuadripléjicos, con el fin de reducir la dependencia de la ayuda de sus padres en las actividades de la vida diaria y el autocuidado. Los datos fueron reunidos entre junio de 2004 y marzo de 2005, sobre la base de una entrevista semiestructurada efectuada a 8 adultos que sufrían de lesión medular alta y que recibían normalmente cuidado domiciliario. Se optó por el sistema de análisis de contenidos a partir de las categorías de significados pautados en los siguientes resultados: apoyo familiar: seguridad para las funciones corporales del discapacitado; tecnología de apoyo: soporte tecnológico para optimizar la calidad de los cuidados; miedos; futuro incierto y pérdida de los padres: los umbrales y las fragilidades humanas; y ganancias funcionales: respuestas objetivas de las funciones corporales. Se concluyó en que el apoyo familiar y, en particular, la presencia de los padres, son fundamentales para enfrentar las limitaciones y reaccionar en la búsqueda de equilibrios en la deficiencia, incapacidad, desventajas y salud de tales pacientes, preparándolos para alcanzar en forma gradual mejoras funcionales e independencia para realizar actividades diarias y ocuparse del autocuidado.The objective of this study was to identify elements of the international classification of functioning, disability and health, applicable to quadriplegic men's home care, to reduce the dependence on their parents' help for activities of daily living and self-care. Data were collected from June 2004 to March 2005. Semi-structured interviews were performed with eight adults with high spinal cord lesions who were being cared for at home . Content analysis was performed based on the categories of meaning extrapolated and the following themes were discovered : family support: safety for the corporal functions of the disabled; supporting technology: inventiveness to promote quality care; fears, uncertain future and parents' loss: thresholds and human fragilities; and functional gains: objective response of body functions. In conclusion, family support, and especially the presence of parents, is fundamental to facing limitations and to reacting in the search for balance with the deficiency, disability, disadvantage and health of that population, preparing them to achieve gradual functional gain and independence for daily activities and self-care
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