DESC field failure evaluation program-`a cradle to grave approach'

The Defense Electronics Supply Center's (DESC's) field failure evaluation program is described. The primary objective of the program is to take positive corrective action steps to assure that quality electronics parts are used in US Department of Defense (DoD) weapon systems. The process flow of field failures from their inception to final corrective action is discussed. To illustrate this, four case studies are presented in which lab testing and coordination with the supplier has resulted in positive corrective action, improving the quality and reliability of the electronic components in DoD weapon systems     

A comparison of total reaction cross section models used in particle and heavy ion transport codes

Understanding the interactions and propagations of high energy protons and heavy ions are essential when trying to estimate the biological effects of Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE) on personnel in space. To be able to calculate the shielding properties of different materials and radiation risks, particle and heavy ion transport codes are needed. In all particle and heavy ion transport codes, the probability function that a projectile particle will collide within a certain distance x in the matter depends on the total reaction cross sections, and the calculated partial fragmentation cross sections scale with the total reaction cross sections. It is therefore crucial that accurate total reaction cross section models are used in the transport calculations. In this paper, different models for calculating nucleon–nucleus and nucleus–nucleus total reaction cross sections are compared with each other and with measurements. The uncertainties in the calculations with the different models are discussed, as well as their overall performances with respect to the available experimental data. Finally, a new compilation of experimental data is briefly presented.