6,517 research outputs found

    Visual exploratory activity in youth soccer players

    Get PDF

    An exploration of romantic adult attachment, marital satisfaction and parenting stress in couples participating in the Supporting Father Involvement Program

    Get PDF
    Over the years attachment theory and research have provided frameworks for understanding infant attachment and adult attachment. More recently, the phenomenon of romantic attachment between couples has been examined. The current mixed-methods study investigates the relationship between romantic adult attachment, marital satisfaction, and parenting stress in partners participating in the Supporting Father Involvement Program. Quantitative and qualitative results indicate that there is an association between adult attachment styles, marital satisfaction, and parenting stress. More specifically, fearful insecurities in mothers are associated with more parenting stress while secure attachments in mothers are connected to more satisfaction in the marital relationship. Fathers with a dismissive attachment have less parenting stress but are happier in their marriages in comparison to secure fathers. Current results shed light on the importance of attachment in reaching a deeper conceptualization of couple relationship dynamics. Future research with a larger and more diverse sample should be conducted in order to extend these initial findings

    Computational Topology Techniques for Characterizing Time-Series Data

    Full text link
    Topological data analysis (TDA), while abstract, allows a characterization of time-series data obtained from nonlinear and complex dynamical systems. Though it is surprising that such an abstract measure of structure - counting pieces and holes - could be useful for real-world data, TDA lets us compare different systems, and even do membership testing or change-point detection. However, TDA is computationally expensive and involves a number of free parameters. This complexity can be obviated by coarse-graining, using a construct called the witness complex. The parametric dependence gives rise to the concept of persistent homology: how shape changes with scale. Its results allow us to distinguish time-series data from different systems - e.g., the same note played on different musical instruments.Comment: 12 pages, 6 Figures, 1 Table, The Sixteenth International Symposium on Intelligent Data Analysis (IDA 2017

    What You Do in High School Matters: The Effects of High School GPA on Educational Attainment and Labor Market Earnings in Adulthood

    Get PDF
    Using abstracted grades and other data from Add Health, we investigate the effects of cumulative high school GPA on educational attainment and labor market earnings among a sample of young adults (ages 24-34). We estimate several models with an extensive list of control variables and high school fixed effects. Results consistently show that high school GPA is a positive and statistically significant predictor of educational attainment and earnings in adulthood. Moreover, the effects are large and economically important for each gender. Interesting and somewhat unexpected findings emerge for race. Various sensitivity tests support the stability of the core findings.High school grades; Educational attainment; Earnings; Panel data

    Experimental investigation of the mechanical stiffness of periodic framework-patterned elastomers

    Get PDF
    Recent advances in the cataloguing of three-dimensional nets mean a systematic search for framework structures with specific properties is now feasible. Theoretical arguments about the elastic deformation of frameworks suggest characteristics of mechanically isotropic networks. We explore these concepts on both isotropic and anisotropic networks by manufacturing porous elastomers with three different periodic net geometries. The blocks of patterned elastomers are subjected to a range of mechanical tests to determine the dependence of elastic moduli on geometric and topological parameters. We report results from axial compression experiments, three-dimensional X-ray computed tomography imaging and image-based finite-element simulations of elastic properties of framework-patterned elastomers

    Private Child Support: Current and Potential Impacts

    Get PDF
    This paper examines the effects of a number of methods for enhancing private child support collections: increasing the proportion of those children potentially eligible for child support who get child support awards; using a uniform standard for determining child support obligations; and collecting a greater percentage of current obligations. The paper also estimates the potential of all three methods used in combination to provide income to needy custodial families. The research demonstrates that the current private child support system falls far short of its potential to transfer income from noncustodial to custodial families. Although the use of a normative standard, improved collections, and extending child support to all those potentially eligible will greatly improve the economic circumstances of impoverished custodial families, private child support cannot be viewed as the sole answer for the economic plight of these families. Increased work opportunities and increased public support are also needed

    Optically trapped atom interferometry using the clock transition of large Rb-87 Bose-Einstein condensates

    Full text link
    We present a Ramsey-type atom interferometer operating with an optically trapped sample of 10^6 Bose-condensed Rb-87 atoms. The optical trap allows us to couple the |F =1, mF =0>\rightarrow |F =2, mF =0> clock states using a single photon 6.8GHz microwave transition, while state selective readout is achieved with absorption imaging. Interference fringes with contrast approaching 100% are observed for short evolution times. We analyse the process of absorption imaging and show that it is possible to observe atom number variance directly, with a signal-to-noise ratio ten times better than the atomic projection noise limit on 10^6 condensate atoms. We discuss the technical and fundamental noise sources that limit our current system, and outline the improvements that can be made. Our results indicate that, with further experimental refinements, it will be possible to produce and measure the output of a sub-shot-noise limited, large atom number BEC-based interferometer. In an addendum to the original paper, we attribute our inability to observe quantum projection noise to the stability of our microwave oscillator and background magnetic field. Numerical simulations of the Gross-Pitaevskii equations for our system show that dephasing due to spatial dynamics driven by interparticle interactions account for much of the observed decay in fringe visibility at long interrogation times. The simulations show good agreement with the experimental data when additional technical decoherence is accounted for, and suggest that the clock states are indeed immiscible. With smaller samples of 5 \times 10^4 atoms, we observe a coherence time of {\tau} = (1.0+0.5-0.3) s.Comment: 22 pages, 6 figures Addendum: 11 pages, 6 figure
    • …
    corecore