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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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Planetary quarantine program studies involving mathematical models for predicting spacecraft contamination, and clean room design
Open-cycle fuel cell development - space radiator optimization, techniques, mathematical models and reliability
Studying the early events that occur after viral infection in humans is difficult unless one intentionally infects volunteers in a human challenge study. Here, we use data about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in such a study in combination with mathematical modeling to gain insights into the relationship between the amount of virus in the upper respiratory tract and the immune response it generates. We propose a set of dynamic models of increasing complexity to dissect the roles of target cell limitation, innate immunity, and adaptive immunity in determining the observed viral kinetics. We introduce an approach for modeling the effect of humoral immunity that describes a decline in infectious virus after immune activation. We fit our models to viral load and infectious titer data from all the untreated infected participants in the study simultaneously. We found that a power-law with a power h < 1 describes the relationship between infectious virus and viral load. Viral replication at the early stage of infection is rapid, with a doubling time of ~2 h for viral RNA and ~3 h for infectious virus. We estimate that adaptive immunity is initiated ~7 to 10 d postinfection and appears to contribute to a multiphasic viral decline experienced by some participants; the viral rebound experienced by other participants is consistent with a decline in the interferon response. Altogether, we quantified the kinetics of SARS-CoV-2 infection, shedding light on the early dynamics of the virus and the potential role of innate and adaptive immunity in promoting viral decline during infection.
Type-5 wind turbines are unique in their use of a permanent magnet synchronous generator, as well as their use of a hydraulic torque converter. This architecture presents an opportunity to provide steady and grid-ready energy without the need for a power converter. With infrastructure continuity and reliability being an important topic amongst renewable energies, researchers have been prompted to further investigate the benefits of type-5 turbines’ unique electromechanical configuration on stable electricity generation. Researchers involved in the WindSG project, SG standing for synchronous generator, are aiming to model a type-5 turbine using Real Time Digital Simulation (RTDS) to evaluate its efficacy in the grid. RSCAD, the software run on the RTDS, comes pre-loaded with electrical and electromechanical components to help simulate electrical generation and grid conditions. However, within this repertoire there is a lack of a component to represent a gearbox with high-fidelity. Within RSCAD’s case studies, the gearbox is often represented simply by a gear ratio value. This presented the task of developing a high-fidelity gearbox model in RSCAD for use in the larger RTDS type-5 wind turbine model. This presentation describes a method of developing a lumped parameter mathematical model to represent a planetary-parallel-parallel gearbox in RSCAD for use in RTDS.
Structural dynamics research on launch vehicles at Langley Research Center, examining analytical method limitations and need for improved mathematical models for vibrational characteristics
Failure to derive adequate mathematical model for neurophysiological processes
First-order nonlinear one-dimensional mathematical model of viscoelasticity using perturbation method
Mathematical models for predicting reliability of semiconductor diodes
Spatial perturbation model for electron behavior in metals with impurities
Stress analysis method of photoelasticity extended to viscoelastic materials by manufacturing mathematical model from transparent birefringent material properties
Structural dynamics research on launch vehicles at Langley Research Center, examining analytical method limitations and need for improved mathematical models for vibrational characteristics
Mathematical model for estimating seal leakage in space vehicle connectors
Nonparametric discrimination theory and mathematical model for electronic component screening
Mathematical models used for space vehicle flight adaptive control systems
Motion stability of earth-orbiting nonsymmetrical satellite with elastically-connected moving parts studied by Liapunov analysis on mathematical model
Lunar landing module Doppler radar system in guidance navigation and control system, studying mathematical model performance
Mathematical models of biological hazards from nuclear rocket engine flight failures
Mathematical model of human pituitary gland mechanism controlling secretions of serum growth hormone in response to glucose deficiency