This document details activities of the Irradiation Processing Department during the month of August, 1958. A general summary is included at the start of the report, after which the report is divided into the following sections: Research and Engineering Operations; Production and Reactor Operations; Facilities Engineering Operation; Employee Relations Operation; and Financial Operation.

ABS>The Gauss-Jordan, Choleski, congruent transformation, and rank annihilation methods for inverting large symmetric positive definite matrices were compared. An attempt was made to consider the effects of both condition and order of the matrix to be inverted on the closeness of the computed inverse to the exact inverse. Each method was programmed in FORTRAN using only single precision arithmetic. Then the error indicators were computed using double precision arithmetic so that the latter calculation was not a limiting factor. It was found that any one of the methods is satisfactory for a well-conditioned least squares matrix of order 10-30. However, when the matrix becomes ill- conditioned then the Gauss-Jordan method appears to be clearly superior (at least for the matrices studied). Algorithms and FORTRAN subroutines for each method are presented. (auth)