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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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Histogram method for combining random variables in predicting microbial burdens on spacecraft
Stochastic differential equations objectives, limitations and restrictive assumptions in physical problems, discussing electromagnetic wave propagation in random continuum or random dAlembertian operator
Nonlinear discrete time sampled systems optimal control by dynamic programming, with application to stochastic systems
Nonlinear Vlasov equation treatment by Fourier- Hermite expansion techniques for plasma problems
Magnetospheric convection models and effects on charged particle populations
Modeling soil mass as continuum using constitutive equations of continuum mechanics
Using FORMAC system to solve optimal control problem of behavior of higher space derivatives of optimal value function along optimal trajectory
Flow equation for representing ion beam current density profile from bombardment ion thrusters
Design and testing of document retrieval system based on development of Boolean file searching instructions and pattern recognition
COPTRAN program and users manual update for space communication system performance testing
LIFTING ROBOT minimum Hamiltonian-steepest ascent multistage lifting booster optimization program input and example problem for mission planning
Manned shuttle comprehensive optimization and targeting program (MASCOT)
Numerical analysis of thermodynamic properties of condenser used with SNAP-8 mjs snap 8 heat exchangers condensers (liquefiers) thermodynamic properties
Iterative solution of least squares programming problem for finite thrust rocket trajectory optimization
Wave equations for motion in stochastic medium, using linear random operator theory
Development of equations to determine communication capability of pulse or digital transmission link is discussed. Equation specifies probability detection error for one-way transmission. Analysis is conducted on IBM 360 computer using FORTRAN 4.
General expressions for the solar radiation force and torques are derived in the vectorial form for any given reflecting surface, provided that the reflecting characteristics of the surface, as well as the value of the solar constant, are known. An appropriate choice of a spacecraft-fixed frame of reference leads to relatively simple expressions for the solar radiation forces and torques in terms of the functions of the sun-spacecraft-earth angle.
The linearized integral equation for the Foucault test of a solid mirror was solved by various methods: power series, Fourier series, collocation, iteration, and inversion integral. The case of the Cassegrain mirror was solved by a particular power series method, collocation, and inversion integral. The inversion integral method appears to be the best overall method for both the solid and Cassegrain mirrors. Certain particular types of power series and Fourier series are satisfactory for the Cassegrain mirror. Numerical integration of the nonlinear equation for selected surface imperfections showed that results start to deviate from those given by the linearized equation at a surface deviation of about 3 percent of the wavelength of light. Several possible procedures for calibrating and scaling the input data for the integral equation are described.