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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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This report gives a summary of the work done in Russia from 1911 to 1914, by Professor Joukowski and his pupils. This summary will show that these men were the true originators of the theory, which combines the theory of the wing element and of the slipstream.
An analysis is given of the causes of the increase in the creep of a material under dynamic loads. A theory of dynamic creep is proposed based on the after-effect theory of Becker.
The requirement of general covariance imparts to metric theories of gravity, such as general relativity, important structural features. A precise mathematical form results, ensuring that computation of observable physical effects in the theory gives the same answers independently of the chosen system of coordinates. This coordinate independence property, in turn, can lead to an equivalence of apparently different physical effects.
Kinetic theory of transport properties of dilute gases, relating it to flames processes, noting assumptions of chapman-enksog theory, discussing real and dusty gases as well as rocket exhausts
Gorkov factorization as basis of self-consistent- field theory /SCF/ formulation of Bardeen- Cooper-Schrieffer theory of superconductivity
System theory - matrices, feedback control system, network synthesis, set theory, stability, shift registers, coding, theorem proving, polynomial roots, channels, and signal flow graphs
Numerical lunar theory to obtain rectangular coordinates for satellite moving in highly inclined orbital plane - Hansen lunar theory
Equations for estimating orbit prediction accuracy theory, with partial derivatives calculated from two-body elliptical orbit theory
Bayesian estimation, decision theory, least squares method, maximum likelihood, and other mathematical techniques of statistical inference theory
Eckert-Brouwer orbit correction formula in general perturbations theory, expressed in rectangular coordinates and variation of astronomical elements, applied to planetary theory
Book on statistical decision theory and sensory processes in signal detection theory and psychophysics
The requirement of general covariance imparts to metric theories of gravity, such as general relavity, important structural features. A precise mathematical form results, ensuring that computation of observable physical effects in the theory gives the same answers independently of the chosen system of coordinates.
Graph theory is used to investigate three different problems arising in air traffic management. First, using a polynomial reduction from a graph partitioning problem, it is shown that both the airspace sectorization problem and its incremental counterpart, the sector combination problem are NP-hard, in general, under several simple workload models. Second, using a polynomial time reduction from maximum independent set in graphs, it is shown that for any fixed e, the problem of finding a solution to the minimum delay scheduling problem in traffic flow management that is guaranteed to be within n1-e of the optimal, where n is the number of aircraft in the problem instance, is NP-hard. Finally, a problem arising in precision arrival scheduling is formulated and solved using graph reachability. These results demonstrate that graph theory provides a powerful framework for modeling, reasoning about, and devising algorithmic solutions to diverse problems arising in air traffic management.
Graph theory is used to investigate three different problems arising in air traffic management. First, using a polynomial reduction from a graph partitioning problem, it isshown that both the airspace sectorization problem and its incremental counterpart, the sector combination problem are NP-hard, in general, under several simple workload models. Second, using a polynomial time reduction from maximum independent set in graphs, it is shown that for any fixed e, the problem of finding a solution to the minimum delay scheduling problem in traffic flow management that is guaranteed to be within n1-e of the optimal, where n is the number of aircraft in the problem instance, is NP-hard. Finally, a problem arising in precision arrival scheduling is formulated and solved using graph reachability. These results demonstrate that graph theory provides a powerful framework for modeling, reasoning about, and devising algorithmic solutions to diverse problems arising in air traffic management.
Points treated in this report are: homogeneous flows, the general study of conical flows with infinitesimal cone angles, the numerical or analogous methods for the study of flows flattened in one direction, and a certain number of results. A thorough consideration of the applications on conical flows and demonstration of how one may solve within the scope of linear theory, by combinations of conical flows, the general problems of the supersonic wing, taking into account dihedral and sweepback, and also fuselage and control surface effects.
This paper contains progress reports of NASA-sponsored studies in the areas of space flight theory and guidance theory. The studies are carried on by several universities and industrial companies. This progress report covers the period from June 15, 1962 to December 20, 1962. The technical supervisor of the contracts is W.E. Miner, Deputy Chief of the Future Projects Branch of Aeroballistics Division, George C. Marshall Space Flight Center.
The progress reports of NASA-sponsored studies in the areas of space flight and guidance theory are presented. The studies are carried on by several universities and industrial companies. This progress report covers the period from July 23, 1964 to April 1, 1965. The contracts are technically supervised by personnel of the Astrodynamics and Guidance Theory Division, Aero-Astrodynamics Laboratory, Marshall Space Flight Center.
Plastic strain and energy density data for cracked plates compared with elastic theory, establishing ductile fracture theory