The design and application of an antenna positioner mechanism for Intelsat-5 series communication satellite

In opertion, the East/West spot beam reflectors on the Intelsat-5 series communication satellite are required to satisfy initial precise-pointing to particular Earth locations; and repositioning and pointing to different Earth locations as traffic changes dictate during the seven year mission. Two 2 axis antenna positioner mechanisms (APM) are utilized in fulfilling these requirements. Each APM is comprised of three components which consist of one center pivot and two linear actuators rather than an integral two axis gimbal design. The step resolution of the APM can be adjusted as required with the present design, at a step resolution of 0.002865 degrees. The design philosophy and considerations, test program, and test results are discussed as well as some major problems encountered during the course of testing and their resolution

An Econometric Analysis of a Production Function for New Zealand

Using the capital stock series recently released by Statistics New Zealand, two approaches have been employed to estimate a production function. The first approach is based on the estimation of a constant elasticity of substitution (CES) production function with a value added form. The second approach is based on a nested CES function. Using the nested structure, we allow imports as an intermediate input in the production block. The estimated results reveal that the data rejects the Cobb-Douglas specification and the use of the value added form is not justifiable.CES production function, Cobb-Douglas specification

Equilibrium shapes of a pair of equal uniform vortices

The shapes and properties of two equal corotating uniform vortices, rotating steadily about each other, are calculated. An integrodifferential equation for the bounding contour is solved numerically, using Newton's method. The results compare well with those obtained from a simple model. It is shown that steady solutions do not exist if the vortices are too close. The stability to two-dimensional disturbances is discussed qualitatively and the critical separation at which the system becomes unstable is calculated. Some comments are made on the stability of a vortex pair of equal counter rotating uniform vortices