10,956 research outputs found

    Computer program VARI-QUIR 3 provides solution of steady-state, multigroup, two-dimensional neutron diffusion equations

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    Computer program VARI-QUIR 3 provides Gauss-Seidel type of solution with inner and outer iterations for steady-state, multigroup, two-dimensional neutron diffusion equations. The program has no restrictions on any of the input parameters such as the number of groups, regions, or materials

    A microprocessor-based one dimensional optical data processor for spatial frequency analysis

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    A high degree of accuracy was obtained in measuring the spatial frequency spectrum of known samples using an optical data processor based on a microprocessor, which reliably collected intensity versus angle data. Stray light control, system alignment, and angle measurement problems were addressed and solved. The capabilities of the instrument were extended by the addition of appropriate optics to allow the use of different wavelengths of laser radiation and by increasing the travel limits of the rotating arm to + or - 160 degrees. The acquisition, storage, and plotting of data by the computer permits the researcher a free hand in data manipulation such as subtracting background scattering from a diffraction pattern. Tests conducted to verify the operation of the processor using a 25 mm diameter pinhole, a 39.37 line pairs per mm series of multiple slits, and a microscope slide coated with 1.091 mm diameter polystyrene latex spheres are described

    Influence of human pressures on large river structure and function

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    A large river study was conducted as part of the Cross Departmental Research Pool (CDRP) ecological integrity project to (i) provide an overview of the macroinvertebrate faunas of large rivers, including those in deep-water habitats, and (ii) to elucidate links between these faunas, river function and anthropogenic stressors. Eleven sites on 6th-order or 7th-order rivers were sampled; four in the South Island and seven in the North Island. We measured (i) macroinvertebrate communities colonising wood, riffles (where present), littoral habitats (1.5 m deep) (ii) ecosystem metabolism using a single-station open-channel approach based on natural changes in dissolved oxygen concentration over a 24-hour period, and (iii) wood and cellulose breakdown. Relationships were investigated between these response variables and reach-scale assessments of habitat quality, underlying upstream and segment environmental variables provided in the Freshwater Environments of New Zealand (FWENZ) database, and anthropogenic pressure variables provided by the Waters of National Importance (WONI) database

    Computer subroutine ISUDS accurately solves large system of simultaneous linear algebraic equations

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    Computer program, an Iterative Scheme Using a Direct Solution, obtains double precision accuracy using a single-precision coefficient matrix. ISUDS solves a system of equations written in matrix form as AX equals B, where A is a square non-singular coefficient matrix, X is a vector, and B is a vector

    Rotationally Modulated X-ray Emission from T Tauri Stars

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    We have modelled the rotational modulation of X-ray emission from T Tauri stars assuming that they have isothermal, magnetically confined coronae. By extrapolating surface magnetograms we find that T Tauri coronae are compact and clumpy, such that rotational modulation arises from X-ray emitting regions being eclipsed as the star rotates. Emitting regions are close to the stellar surface and inhomogeneously distributed about the star. However some regions of the stellar surface, which contain wind bearing open field lines, are dark in X-rays. From simulated X-ray light curves, obtained using stellar parameters from the Chandra Orion Ultradeep Project, we calculate X-ray periods and make comparisons with optically determined rotation periods. We find that X-ray periods are typically equal to, or are half of, the optical periods. Further, we find that X-ray periods are dependent upon the stellar inclination, but that the ratio of X-ray to optical period is independent of stellar mass and radius.Comment: 10 pages, 8 figures, accepted for publication in MNRA

    Injection and acceleration with physics optics in LEP

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    Up to now injection into LEP has been done using a dedicated injection optics, with a vertical b*v = 21 cm. After accelerating to higher energies a progressive optics change is made with beam to the physics¹ optics, where b*v = 5 cm. The use of synchrotron injection as the normal means of accumulation in LEP has opened up the possibility of injecting directly into the physics¹ optics. This has many advantages ranging from an easier operation, including a faster turnaround from injection to physics conditions, to allowing more flexibility in the optics design and matching. Results from machine development sessions are presented showing that there is no fundamental reason for not implementing this scheme. Potential drawbacks and limitations, especially for the maximum accumulated beam current are, however, discussed

    The Hidden Pandemic: A Qualitative Study on How Middle-Aged Women Make Sense Of Managing Their Long Covid Symptoms

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    Long covid is a challenging and debilitating health condition because of its remitting and relapsing nature and a person living with long covid can feel like they are getting better and recovering only to relapse again. The aim of the research was to explore how non hospitalised middle-aged women who contracted covid in the first wave of the pandemic, from March 2020, are managing their long covid symptoms. A Qualitative research study with an Interpretative Phenomenological Analysis approach was utilised to explore how the women made sense of managing their condition and health seek behaviours. Participants were recruited from long covid Facebook groups and semi-structured Interviews were conducted remotely by Teams audio which were digitally recorded and transcribed by hand with prior informed consent. 9 women were interviewed and four themes and 8 sub themes emerged from the data. The four emerging themes were: Inequality and inconsistent medical treatment; Uncertainty and ambiguity of managing long covid symptoms; Managing other people’s expectations and perceptions of long covid and The changing identity. Overall, these results indicated a general mistrust in health care services to provide adequate support and individualised treatment plans leading women to self-advocacy and to seek alternative support and treatment. This article raised important questions about the nature of how women are still being unfairly treated when seeking medical attention
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