3,183 research outputs found

    Codes from incidence matrices and line graphs of Hamming graphs

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    AbstractWe examine the p-ary codes, for any prime p, that can be obtained from incidence matrices and line graphs of the Hamming graphs, H(n,m), obtaining the main parameters of these codes. We show that the codes from the incidence matrices of H(n,m) can be used for full permutation decoding for all m,n≥3

    Mid-Career Adult Learners in an Online Doctoral Program and the Drivers of Their Academic Self-Regulation: The Importance of Social Support and Parent Education Level

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    Adult professionals enroll in online graduate programs and rely on social support and on their ability to self-regulate to be successful. The literature on academic self-regulation among emerging adults (traditional college age) is ample, but we do not know how social support interacts with academic self- regulation among adult graduate students at mid-career, particularly among those students who are first generation college goers. This study addressed the following questions: (1) To what degree do parental education level and cohort progression predict academic self-regulation? and (2) What sources of social support – family, friends, loved one (significant other), and classmates – are predictive of academic self- regulation for adult students in an online doctoral program? Findings include evidence that the influence of parental educational level on academic self-regulation persists through midlife. Also, that perceived social support from family, friends, and peers predicts academic self-regulation. We conclude with implications for the design of online programs

    Color matches in diseased eyes with good acuity: detection of deficits in cone optical density and in chromatic discrimination

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    Reduced foveal cone optical density in diseased eyes with normal acuity can affect color matches. Using field diameters of 1 ± , 2 ± , 4 ± , and 8 ± , we measured mean color-match midpoints and match widths in patients who had good acuity and who exhibited three categories of eye disease: hereditary macular degeneration (n 12), retinitis pigmentosa (n 19), and glaucoma (n 18). Results were compared with those for normal observers of comparable ages. Mean color-match midpoints were abnormal only for the population with hereditary macular degeneration, indicating a reduction in cone optical density in the central 4 ± . Mean color-match widths were enlarged for both hereditary macular degeneration and retinitis pigmentosa, a result consistent with a reduction in the number of foveal cones

    Codes from adjacency matrices of uniform subset graphs

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    Studies of the p-ary codes from the adjacency matrices of uniform subset graphs Γ(n,k,r)Γ(n,k,r) and their reflexive associates have shown that a particular family of codes defined on the subsets are intimately related to the codes from these graphs. We describe these codes here and examine their relation to some particular classes of uniform subset graphs. In particular we include a complete analysis of the p-ary codes from Γ(n,3,r)Γ(n,3,r) for p≥5p≥5 , thus extending earlier results for p=2,3p=2,3

    VLBA Observations of G5.89–0.39: OH Masers and Magnetic Field Structure

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    We present VLBA observations of 1667 MHz OH maser emission from the massive star formation region G5.89-0.39. The observations were phase-referenced, allowing the absolute positions of the masers to be obtained. The 1667 MHz masers have radial velocities that span ~50 km s^(-1) but show little evidence of tracing the bipolar molecular outflow, as has been claimed in previous studies. We identify 23 Zeeman pairs through comparison of masers in left and right circular polarization. Magnetic field strengths range from -2 to +2 mG, and an ordered reversal in magnetic field direction is observed toward the southern region of the UC H II region. We suggest that the velocity and magnetic field structure of the 1667 MHz masers can be explained in the context of a model in which the masers arise in a neutral shell just outside a rapidly expanding ionized shell

    Graphs, designs and codes related to the n-cube

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    For integers n 1; k 0, and k n, the graph k n has vertices the 2n vectors of Fn 2 and adjacency defined by two vectors being adjacent if they differ in k coordinate positions. In particular 1 n is the n-cube, usually denoted by Qn. We examine the binary codes obtained from the adjacency matrices of these graphs when k D 1; 2; 3, following the results obtained for the binary codes of the n-cube in Fish [Washiela Fish, Codes from uniform subset graphs and cyclic products, Ph.D. Thesis, University of the Western Cape, 2007] and Key and Seneviratne [J.D. Key, P. Seneviratne, Permutation decoding for binary self-dual codes from the graph Qn where n is even, in: T. Shaska, W. C Huffman, D. Joyner, V. Ustimenko (Eds.), Advances in Coding Theory and Cryptology, in: Series on Coding Theory and Cryptology, vol. 2, World Scientific Publishing Co. Pte. Ltd., Hackensack, NJ, 2007, pp. 152 159 ]. We find the automorphism groups of the graphs and of their associated neighbourhood designs for k D 1; 2; 3, and the dimensions of the ternary codes for k D 1; 2. We also obtain 3-PD-sets for the self-dual binary codes from 2 n when n 0 .mod 4/, n 8

    Graphs, designs and codes related to the n-cube

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    For integers n 1; k 0, and k n, the graph k n has vertices the 2n vectors of Fn 2 and adjacency defined by two vectors being adjacent if they differ in k coordinate positions. In particular 1 n is the n-cube, usually denoted by Qn. We examine the binary codes obtained from the adjacency matrices of these graphs when k D 1; 2; 3, following the results obtained for the binary codes of the n-cube in Fish [Washiela Fish, Codes from uniform subset graphs and cyclic products, Ph.D. Thesis, University of the Western Cape, 2007] and Key and Seneviratne [J.D. Key, P. Seneviratne, Permutation decoding for binary self-dual codes from the graph Qn where n is even, in: T. Shaska, W. C Huffman, D. Joyner, V. Ustimenko (Eds.), Advances in Coding Theory and Cryptology, in: Series on Coding Theory and Cryptology, vol. 2, World Scientific Publishing Co. Pte. Ltd., Hackensack, NJ, 2007, pp. 152 159 ]. We find the automorphism groups of the graphs and of their associated neighbourhood designs for k D 1; 2; 3, and the dimensions of the ternary codes for k D 1; 2. We also obtain 3-PD-sets for the self-dual binary codes from 2 n when n 0 .mod 4/, n 8

    A Low Cost, Portable Fluorescence Correlation Spectrometer for Disease Diagnosis

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    People being treated for HIV need to periodically test to determine if their antiviral medication is effectively keeping their viral loads at a safe level. Individuals living in rural areas of developing countries would be more likely to get these viral load tests if an instrument existed which reduced costs and was small and rugged enough to be brought to the client rather than require the client to travel for hours to a clinic. The Diagnostics for Viral Disease team is developing such a device in cooperation with Dr. Edgar Simulundu and the Macha Research Trust in Zambia. Our design is based on advanced fluorescence spectroscopy utilizing a fluorescence protein probe, confocal optics, and low-cost, low-power electronics. This poster reviews work done in three subsystems of the overall instrument. First, we have optimized the program used during burst analysis spectroscopy for identification of individual viruses in dilute samples. Second, we have confirmed the operation of the amplifying and discriminating sections of the photon processing circuitry which converts light pulses into a digital signal ready to be processed in the signal analysis subsystem. Finally, we have completed the Field Programmable Gate Array (FPGA) and Raspberry Pi programming allowing successful transfer of the results of the signal processing in the FPGA to the Raspberry Pi for display to the end user. Going forward we will integrate these subsystems into a fully functional exploded prototype ready for the final stage of condensing the design into a portable prototype that can be tested and delivered to our client. Funding for this work provided by The Collaboratory for Strategic Partnerships and Applied Research.https://mosaic.messiah.edu/engr2022/1003/thumbnail.jp
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