49,027 research outputs found

    A compact finite element method for elastic bodies

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    A nonconforming finite method is described for treating linear equilibrium problems, and a convergence proof showing second order accuracy is given. The close relationship to a related compact finite difference scheme due to Phillips and Rose is examined. A condensation technique is shown to preserve the compactness property and suggests an approach to a certain type of homogenization

    A finite difference treatment of Stokes-type flows: Preliminary report

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    The equations Laplacian operator omega = 0, (1.1a) and omega = Laplacian operator Chi, (1.1b) describe, in suitable units, 2-D Stokes flow of an incompressible fluid occupying a domain D in which omega is the vorticity and Chi is the stream function. The flow is uniquely determined by specifying the velocity on the boundary B of D, a condition which leads to specifying the stream function Chi and its normal derivative Chi sub n on B. A mathematically similar problem arises in describing the equilibrium of a flat plate in structural mechanics where a related 1-D problem by finite difference or finite element methods is to introduce effective methods for imposing the boundary conditions through which (1.1a) is coupled to (1.1b). These models thus provide a simple starting point for examining the general treatment of boundary conditions for more general time dependent Navier-Stokes incompressible flows. For the purpose of discussion it is assumed that D is a square domain. A standard finite difference method to solve (1.1) is to introduce a uniform grid and then use standard five point finite difference operators to express each equation in (1.1). At any point on the boundary B a value of Chi is specified by the boundary conditions but a value of omega at the same boundary mesh point will also be required to complete the computation. Methods are discussed which overcome the difficulty in solving these problems

    MacMahon's sum-of-divisors functions, Chebyshev polynomials, and Quasi-modular forms

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    We investigate a relationship between MacMahon's generalized sum-of-divisors functions and Chebyshev polynomials of the first kind. This determines a recurrence relation to compute these functions, as well as proving a conjecture of MacMahon about their general form by relating them to quasi-modular forms. These functions arise as solutions to a curve-counting problem on Abelian surfaces.Comment: 6 Page

    Asian American women\u27s resilience: An integrative review

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    Asian American women face unique stressors that threaten their overall health and well-being. However, resilience is a phenomenon that allows individuals to develop positive adaptation despite adversities and challenges. This integrative review is conducted in order to explore the current state of knowledge regarding the resilience of Asian American women. Twelve databases were used to identify related articles: Academic Search Premier, CINAHL, ERIC, Ethnic NewsWatch, GenderWatch, ProQuest Dissertations and Theses Global, ProQuest Sociological Abstracts, PsycINFO, PubMed, SAGE (Psychology and Sociology collections), Scopus, and Web of Science. Twenty-one research studies met the inclusion criteria of the integrative review. Five common themes emerged from the analysis of the studies: (a) resilience as conceptualized as a coping strategy, (b) resilience as related to social support and network, (c) resilience as an enduring phenomenon, (d) resilience as connected to bicultural identity, and (e) resilience as an emancipatory perspective and experience. These themes imply that resilience is a developmental process, culture has a significant influence on resilience, and Asian American women are a vulnerable and marginalized group. Further recommendations for nursing practice and research are discussed as related to these implications

    Deformations of colored sl(N) link homologies via foams

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    We generalize results of Lee, Gornik and Wu on the structure of deformed colored sl(N) link homologies to the case of non-generic deformations. To this end, we use foam technology to give a completely combinatorial construction of Wu's deformed colored sl(N) link homologies. By studying the underlying deformed higher representation theoretic structures and generalizing the Karoubi envelope approach of Bar-Natan and Morrison we explicitly compute the deformed invariants in terms of undeformed type A link homologies of lower rank and color.Comment: 64 pages, many figure

    Coal-rock interface detector

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    A coal-rock interface detector is presented which employs a radioactive source and radiation sensor. The source and sensor are separately and independently suspended and positioned against a mine surface of hydraulic pistons, which are biased from an air cushioned source of pressurized hydraulic fluid
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