325 research outputs found

    A simulator study of the supersonic transport in the air traffic control system

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    Real time environment and control simulation of supersonic transport in air traffic control syste

    Flight tests of a direct lift control system during approach and landing

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    Flight tests of modified aileron direct lift control system during approach and landing of F8-C aircraf

    Polygraphs in Employment: A State Survey

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    Two types of laws govern the use of polygraphs in the employment setting: those aimed at restricting employers\u27 use of such tests and those delineating the qualifications and conduct of polygraph examiners. This Article will survey and compare the present status of state laws relating to employer use of polygraph testing and the licensing of polygraph examiners. A brief background of the development of the polygraph is included, as well as a description of testing procedures, an assessment of test validity, and recommendations for a national uniform approach to polygraphs

    Dragonfly: Investigating the Surface Composition of Titan

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    Dragonfly is a rotorcraft lander mission, selected as a finalist in NASA's New Frontiers Program, that is designed to sample materials and determine the surface composition in different geologic settings on Titan. This revolutionary mission concept would explore diverse locations to characterize the habitability of Titan's environment, to investigate how far prebiotic chemistry has progressed, and to search for chemical signatures that could be indicative of water-based and/or hydrocarbon-based life. Here we describe Dragonfly's capabilities to determine the composition of a variety of surface units on Titan, from elemental components to complex organic molecules. The compositional investigation ncludes characterization of local surface environments and finely sampled materials. The Dragonfly flexible sampling approach can robustly accommodate materials from Titan's most intriguing surface environments

    After DART: Using the First Full-scale Test of a Kinetic Impactor to Inform a Future Planetary Defense Mission

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    NASA’s Double Asteroid Redirection Test (DART) is the first full-scale test of an asteroid deflection technology. Results from the hypervelocity kinetic impact and Earth-based observations, coupled with LICIACube and the later Hera mission, will result in measurement of the momentum transfer efficiency accurate to ∼10% and characterization of the Didymos binary system. But DART is a single experiment; how could these results be used in a future planetary defense necessity involving a different asteroid? We examine what aspects of Dimorphos’s response to kinetic impact will be constrained by DART results; how these constraints will help refine knowledge of the physical properties of asteroidal materials and predictive power of impact simulations; what information about a potential Earth impactor could be acquired before a deflection effort; and how design of a deflection mission should be informed by this understanding. We generalize the momentum enhancement factor β, showing that a particular direction-specific β will be directly determined by the DART results, and that a related direction-specific β is a figure of merit for a kinetic impact mission. The DART β determination constrains the ejecta momentum vector, which, with hydrodynamic simulations, constrains the physical properties of Dimorphos’s near-surface. In a hypothetical planetary defense exigency, extrapolating these constraints to a newly discovered asteroid will require Earth-based observations and benefit from in situ reconnaissance. We show representative predictions for momentum transfer based on different levels of reconnaissance and discuss strategic targeting to optimize the deflection and reduce the risk of a counterproductive deflection in the wrong direction
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