William A. Beard

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This paper considers the problem of reorienting a constellation of spacecraft such that the fuel distributed across the constellation is both conserved and expended uniformly. Results are derived for constellations with an arbitrary number of spacecraft, assuming that 1 the constellation is in free space, that the spacecraft mass is time-invariant, and that(More)
In this paper we use the recently introduced concept of satisscing decision theory to develop stabilizing state-feedback control strategies for nonlinear systems. The result is a pointwise \satisscing" set of control options from which a continuous feedback strategy can be selected. We show that the set of continuous \satis-cing" control strategies can be(More)
Although the primary function of DNA polymerase (pol) β is associated with gap-filling DNA synthesis as part of the DNA base excision repair pathway, translesion synthesis activity has also been described. To further understand the potential role of pol β-catalyzed translesion DNA synthesis (TLS) and the structure-function relationships of specific residues(More)
This paper considers the problem of reorienting a constellation of spacecraft such that the fuel distributed across the constellation is both conserved and expended uniformly. The spacecraft constellation is controlled to reorient while maintaining the relative positions of the spacecraft such that the constellation is held in formation throughout the(More)
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