As the reference frame the orbital system is adopted. This system has been shown by KOZAI and KINOSHITA.2) In this system the inclination and the argument of perigee are referred to the instantaneous equator of date, and the longitude of the node is measured from the mean equinox of 1950.0 along the mean equator of 1950.0 and then along the instantaneous equator of date. The earth is rotating uniformly in this system, thus giving a particularly simple expression for the sidereal angle.
The LAGRANGE's planetary equations in their usual form which hold for the orbital elements referred to the non-rotating axial system defined at 1950.0 are used. Then the equations are modified to include the effects of motion of the reference system and transformed into GAUSSIAN form. Because of this motion partial derivatives of orbital elements with respect to time are introduced in the equations.
The partial derivatives are derived from the expressions including the terms up to the third order of precession.
By the method of linear perturbations the equations are solved and the perturbations to satellite equatorial orbital elements by the motion of the equatorial plane are obtained.

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This paper describes the performance of the composite wick heat pipe, which has two kinds of wicks, namely, circumferential grooves as a pumping wick and sintered stainless metal felt as a transport wick.
The maximum heat transfer rate and evaporator heat transfer coefficient was obtained by changing the influential parameters; groove geometry, porosity of felt, evaporator length and inclination angle. And a theoretical model has been developed to predict the maximum heat transfer rate of this type of the composite wick heat pipe. In this model, a liquid recession into the bottom of the groove due to the increased heat transfer rate, so called "LEVERETT effect, " was taken into consideration.
It is concluded that the predicted maximum heat transfer rate agrees well with the experimental data.

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Numerical determination of the minimum drag profile in the STOKES flow was attempted in accordance with PIRONNEAU's algorithm. Finite element method was used in the numerical calculation for solving the flow field because it was easy to change the body shape. It is the purpose that the minimum drag profile in the two-dimensional finite region is numerically obtained by calculating the minimum energy-dissipationrate profile. If the operation of changing the body shape was begun from the circle as the initial body shape and the iteration was continued, a series of the body shapes that satisfied the PIRONNEAU's necessary condition was obtained. In the process of changing the body shape, the energy dissipation rate, the norm distribution, the pressure distribution along the body surface, the flow field around the body and the drag were calculated.

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This paper describes the experimental study on the relation between aerodynamic drag and vorticities in incompressible flow. Diffusion of vorticities of shedding vortices in three-dimensionalized wakes behind tapered cylinders and a thick plate with a serrated trailing edge was investigated and discussed in relation to the mechanism leading to the base drag reduction. These results are not contradictory to the analytical concept obtained by the energy integral of NAVIER-STOKES equation, which suggests to minimize the volume integral of the square of vorticities in order to reduce the total drag.

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The wing flutter phenomenon of the modern airplanes is mainly of torsion mode. The rotation dynamic absorber, which is attached to the elastic axis of the wing, can be considered to have a good effect for the suppression of the wing flutter. In this paper the problem is treated as three degree of freedom system, consisting of the bending of the wing and its torsion and the rotation of the dynamic absorber. The analysis shows the method to determine the following three values; the optimum natural frequency of the dynamic absorber, its optimum structural damping and the corresponding maximum flutter velocity. From these results, it is also explained that the increase of the flutter velocity due to the rotation dynamic absorber is approximately proportional to the square root the moment of inertia of the absorber.

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This paper is concerned with the direction control of a free jet issued from a circular nozzle into a still air. The direction control was done by tilting a pair of flat vanes set at the exit of nozzle, varying the vane angle and the gap between vanes. The distributions of velocity and static pressure, the spread of jet flow and the deflection of the line of maximum velocity were measured.

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