On the generation of satellite position (and velocity) by a mixed analytical-numerical procedure

The generation of accurate Earth-satellite ephemerides by numerical integration, over a period of perhaps weeks, can consume an inordinate amount of computer time. No satisfactory purely analytical procedure exists, but if short-period components of the standard elliptic elements are removed analytically, the resulting mean elements can be integrated with a step time that is longer than the satellite's orbital period.The definition of the mean elements depends on the particular perturbations included in the orbit generator and regarded as non-resonant. It is best if short-period perturbations are not applied to the orbital elements themselves but to the satellite's position (and velocity if required), expressed in a system of cylindrical polar coordinates, and the paper shows how mean elements can be recovered from position and velocity.A computer program has been written to test the proposed procedure for generating ephemerides, using a truncated potential field. Some results from this program are presented.     

Evaluation of three ATE test environments

It is often difficult to assess the positive and negative issues facing the use of a particular software test environment in a given application. Much of the literature is swayed by the use of each environment by a single application. This paper will provide detailed information on ARGO Systems evaluation of three popular ATE Test Environments: the Ada Based Environment for Testing (ABET), the TYX PAWS ATLAS test environment and the National Instruments LabVIEW graphical test environment. This evaluation was accomplished by comparing the same test program measurements in each environment using the same UUT, interface test adapter, and the same PC-based ATE. As such, the data represents a true apples-to-apples comparison of these environments     

VSI plug 'n pray

VXI has grown substantially in applications from testing in the lab to field support of weapon systems. While the hardware interfaces have been well defined for some time, the software is still struggling. Industry hype infers that integrating VXI resources is just a “plug and play” affair that anyone should be able to do. This paper explores some of the pitfalls of integrating VXI resources from different (and sometimes the same) suppliers that make this more challenging than you might think