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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Flow spoiler and aerodynamic balance effects on oscillating hinge moments for swept fin-rudder combination in transonic wind tunnel
Approximate solution for elastic equilibrium of hinge-supported shallow spherical shell
Differential equation system for elastic equilibrium of hinge-clamped shallow spherical shell bounded by ellipse and rectangle
A comparative evaluation was made for all-movable delta and flap-type controls on several wing plan forms. Comparison of these experimental results from various test facilities shows the effectiveness on various wing plan forms and an evaluation of hinge-moment characteristics of all-movable delta controls, swept trailing-edge flap, and straight trailing-edge flap-type controls.
This presentation describes the interface hinge moments loads collected during the ACTE flights.
The further development and modifications made towards the integration of the upper and lower hinge assemblies for the Exploration Upper Stage umbilical are presented. Investigative work is included to show the process of applying updated NASA Standards within component and assembly drawings for selected manufacturers. Component modifications with the addition of drawings are created to precisely display part geometries and geometric tolerances, along with proper methods of fabrication. Comparison of newly updated components with original Apollo era components is essential to correctly model the part characteristics and parameters, i.e. mass properties, material selection, weldments, and tolerances. 3-Dimensional modeling software is used to demonstrate the necessary improvements. In order to share and corroborate these changes, a document management system is used to store the various components and associated drawings. These efforts will contribute towards the Mobile Launcher for Exploration Mission 2 to provide proper rotation of the Exploration Upper Stage umbilical, necessary for providing cryogenic fill and drain capabilities.
Abstract Coronavirus spike glycoproteins presented on the virion surface mediate receptor binding, and membrane fusion during virus entry and constitute the primary target for vaccine and drug development. How the structure dynamics of the full-length spikes incorporated in viral lipid envelope correlates with the virus infectivity remains poorly understood. Here we present structures and distributions of native spike conformations on vitrified human coronavirus NL63 (HCoV-NL63) virions without chemical fixation by cryogenic electron tomography (cryoET) and subtomogram averaging, along with site-specific glycan composition and occupancy determined by mass spectrometry. The higher oligomannose glycan shield on HCoV-NL63 spikes than on SARS-CoV-2 spikes correlates with stronger immune evasion of HCoV-NL63. Incorporation of cryoET-derived native spike conformations into all-atom molecular dynamic simulations elucidate the conformational landscape of the glycosylated, full-length spike that reveals a role of hinge glycans in modulating spike bending. We show that glycosylation at N1242 at the upper portion of the stalk is responsible for the extensive orientational freedom of the spike crown. Subsequent infectivity assays implicated involvement of N1242-glyan in virus entry. Our results suggest a potential therapeutic target site for HCoV-NL63.
Passive membrane permeability of N-methylated macrocyclic peptides remains poorly understood because high-energy conformational intermediates are rarely sampled by conventional methods. Using the deep learning–driven rare-event sampling framework ES-CRUMPLE, we show that cyclosporine A accesses transient amphiphilic states via a localized conformational hinge at Ala7/d-Ala8, revealing a kinetic design handle that is invisible to population-based analyses.
In nature, proteins that switch between two conformations in response to environmental stimuli structurally transduce biochemical information in a manner analogous to how transistors control information flow in computing devices. Designing proteins with two distinct but fully structured conformations is a challenge for protein design as it requires sculpting an energy landscape with two distinct minima. Here, in this work, we describe the design of “hinge” proteins that populate one designed state in the absence of ligand and a second designed state in the presence of ligand. X-ray crystallography, electron microscopy, double electron-electron resonance spectroscopy, and binding measurements demonstrate that despite the significant structural differences the two states are designed with atomic level accuracy and that the conformational and binding equilibria are closely coupled.
Control trailing-edge thickness and aspect ratio effect on oscillating hinge-moment and flutter characteristics of flap-type controls
Supersonic wind tunnel determination of nozzle hinge-moment coefficients for saturn i with & without jet flow
High angular stresses in fluid-handling ducts are accommodated by a lightweight hinged bellows restraint. This device transmits angular stress to points close to the axis center and spreads it over a rigid configuration.
Metal knee hinge with an adjustable sleeve worn on the outside of a leg cast facilitates movement of the knee joint. This helps eliminate stiffness of the knee and eliminates bulkiness and adjustment difficulty.
Calculated and experimental hinge moments on trailing-edge flaps of swept delta wings at hypersonic speeds and positive deflection angles
Heat transfer and pressure distributions inside hinge line gap of wedge-flap combination at hypersonic speeds
Performance tests on dynamic jettison hinge loads of Centaur nose fairing
Auxiliary inlet ejector nozzle with fixed doors and single-hinge trailing-edge flaps
Performance of auxiliary inlet ejector nozzle with fixed inlet doors and triple-hinge trailing edge flap over subsonic and transonic free stream range for supersonic aircraft