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Kirk, D.

Publications and source records attributed to Kirk, D..

Effect of initial conditions on deduced atmosphere for Uranus and Jupiter entries

Atmosphere reconstruction based on the data from a probe is discussed in terms of the effect of errors in entry velocity and entry flight path angle on the determination of density, pressure, and temperature as functions of altitude. Emphasis is placed on Uranus and Jupiter entries, although Saturn entries are included.

Kirk, D.

Nonlinear parameter identification: Ballistic range experience applicable to flight testing

The parameter identification scheme being used is a differential correction least squares procedure (Gauss-Newton method). The position, orientation, and derivatives of these quantities with respect to the parameters of interest (i.e., sensitivity coefficients) are determined by digital integration of the equations of motion and the parametric differential equations. The application of this technique to three vastly different sets of data is used to illustrate the versatility of the method and to indicate some of the problems that still remain.

Chapman, G.