4,216 research outputs found

    Is Quantitative Research Ethical? Tools for Ethically Practicing, Evaluating, and Using Quantitative Research

    Get PDF
    This editorial offers new ways to ethically practice, evaluate, and use quantitative research (QR). Our central claim is that ready-made formulas for QR, including 'best practices' and common notions of 'validity' or 'objectivity,' are often divorced from the ethical and practical implications of doing, evaluating, and using QR for specific purposes. To focus on these implications, we critique common theoretical foundations for QR and then recommend approaches to QR that are 'built for purpose,' by which we mean designed to ethically address specific problems or situations on terms that are contextually relevant. For this, we propose a new tool for evaluating the quality of QR, which we call 'relational validity.' Studies, including their methods and results, are relationally valid when they ethically connect researchers' purposes with the way that QR is oriented and the ways that it is done—including the concepts and units of analysis invoked, as well as what its 'methods' imply more generally. This new way of doing QR can provide the liberty required to address serious worldly problems on terms that are both practical and ethically informed in relation to the problems themselves rather than the confines of existing QR logics and practices.cited By

    Variable stiffness torsion springs

    Get PDF
    In a torsion spring the spring action is a result of the relationships between the torque applied in twisting the spring, the angle through which the torsion spring twists, and the modulus of elasticity of the spring material in shear. Torsion springs employed industrially have been strips, rods, or bars, generally termed shafts, capabable of being flexed by twisting their axes. They rely on the variations in shearing forces to furnish an internal restoring torque. In the torsion springs herein the restoring torque is external and therefore independent of the shearing modulus of elasticity of the torsion spring shaft. Also provided herein is a variable stiffness torsion spring. This torsion spring can be so adjusted as to have a given spring constant. Such variable stiffness torsion springs are extremely useful in gimballed payloads such as sensors, telescopes, and electronic devices on such platforms as a space shuttle or a space station

    Novel Distances for Dollo Data

    Full text link
    We investigate distances on binary (presence/absence) data in the context of a Dollo process, where a trait can only arise once on a phylogenetic tree but may be lost many times. We introduce a novel distance, the Additive Dollo Distance (ADD), which is consistent for data generated under a Dollo model, and show that it has some useful theoretical properties including an intriguing link to the LogDet distance. Simulations of Dollo data are used to compare a number of binary distances including ADD, LogDet, Nei Li and some simple, but to our knowledge previously unstudied, variations on common binary distances. The simulations suggest that ADD outperforms other distances on Dollo data. Interestingly, we found that the LogDet distance performs poorly in the context of a Dollo process, which may have implications for its use in connection with conditioned genome reconstruction. We apply the ADD to two Diversity Arrays Technology (DArT) datasets, one that broadly covers Eucalyptus species and one that focuses on the Eucalyptus series Adnataria. We also reanalyse gene family presence/absence data on bacteria from the COG database and compare the results to previous phylogenies estimated using the conditioned genome reconstruction approach

    Means for Positioning and Repositioning Scanning Instruments

    Get PDF
    A method is presented for positioning a scanning instrument to point toward the center of the desired scan wherein the scan is achieved by rotating unbalanced masses (RUMs) rotating about fixed axes of rotation relative to and associated with the instrument, the RUMs being supported on drive shafts spaced from the center of the mass of the instrument and rotating 180 degrees out-of-phase with each other and in planes parallel to each other to achieve the scan. The elevation and cross-elevation angles of the instrument are sensed to determine any offset and offset time rate-of-change, and the magnitude and direction are converted to a RUM cycle angular velocity component to be superimposed on the nominal velocity of the RUMs. This RUM angular velocity component modulates the RUM angular velocity to cause the speed of the RUMs to increase and decrease during each revolution to drive the instrument toward the desired center of the scan
    • …
    corecore