Report discussing part of a study that aims to understand plasma stability and confinement in mirror geometries.

Summary. The analysis of the motion of a six-bar linkage is difficult because of the large number of variables involved and the large number of calculations that have to be made for each position of the linkage. If a digital computer is used to make the calculations required for a multi-position analysis of a mechanism, it is feasible to design by analyzing a large numbers of similar linkages and selecting the optimum configuration. In this paper expressions have been derived for the output angle as a function of the input angle and the transmission angle as a function of the input angle for any single-degree-of-freedom six-bar linkage for which the parameters are known An example showing the usefulness of a six-bar computer program as a mechanism design tool is discussed.

Abstract. The waveform or character of a refraction arrival has become internationally important because of its use in determining source parameters. An approximate theoretical machine calculation has been made to show the effect of layering above a refractor on the character of the refraction arrival. The method is illustrated with a geologic model taken from the Edwards Plateau area of West Texas. The effect of the Edwards limestone, Comanche, and Trinity formations on the refraction from the Pennsylvanian limestone is computed. The conversion of energy in theses upper layers from compressional to shear plays a significant role in forming the refraction character. An anticlinal structure is introduced into the Pennsylvanian limestone and it is argued that, in a first approximation, the wave in the Pennsylvanian limestone follow the structure, refracting off at the critical angle as before. Now, however, the angle of incidence on the base of the Trinity is a function of the angle of the structure. Since the amplitudes of converted waves depends n this angle, The character of the refraction arrival depends in a predictable way on the angle in the structure where the critical refraction has taken lace. These results are theoretical and only approximate, but …

The wide use of liquid oxygen as an oxidant in rocket engines has resulted in an increased interest in low-temperature heat transfer. Storage tanks for this type of application, being uninsulated, contain a boiling-liquid low-temperature sink, which is susceptible to environmental heat inputs and subsequent liquid loss by vaporization. Such losses are difficult to predict due to the complex combination of ambient conditions which exist, and the lack of knowledge concerning their combined effects. Heat transfer in this field is difficult to analyze primarily because of its transient nature. This is a result of such factors as: (1) the growth of an insulating frost layer on the outer surface of the container, with its accompanying energy transfer to the system; (2) the temperature dependent convective air pattern that surrounds the container, (3) the transfer of radiant energy to the system, and (4) the mechanical failure of the frost itself with subsequent sloughing from the container wall. A lack of knowledge regarding the coefficient of diffusion of water vapor through air and the thermal conductivity of frost in this depressed temperature range further complicates the predictions of heat transfer.

The problem of the reduction of an arbitrary truth function to the minimal union of basic cells is discussed. The solution to this problem has applications to pattern recognition and logical circuit design. An algorithm is presented that solves the problem and generates the class of minimal unions. It partitions an arbitrary truth function into a well-defined set of subfunctions (components) in such a way that the partition is invariant under all transformations that preserve the topology of the original truth function.

A variable-length vacuum-insulated liquid hydrogen transfer line is described. The vacuum system is semi-permanent, and segments of the line are assembled with only threaded vacuum fittings. Thermal stress calculations are presented for a statically indeterminate union coupling.

The problem of crystal structure of the martensitic B1 phase of the eutectic alloy in the Cu-Al system still requires a more accurate clarification (Hun ger and Dienst 1960, Tarora 1949). Martensitic phases in general are formed through small thrust (shear) deformations of the original lattice. On this basis the results of Hunger and Dienst (1960) are doubtful, since the lattice constants found by them have required a considerable reclassification. From the known lattice constants of the B1 phase (Tarora, 1949) and the orientation relationships of the B1 phase (Wassermann, 1934) one has expected a hexagonal lattice for the martensitic phase with [formula].