DISPL is a software package for solving some second-order nonlinear systems of partial differential equations including parabolic, elliptic, hyperbolic, and some mixed types such as parabolic-elliptic equations. Fairly general nonlinear boundary conditions are allowed as well as interface conditions for problems in an inhomogeneous media. The spatial domain is one- or two-dimensional with Cartesian, cylindrical, or spherical (in one dimension only) geometry. The numerical method is based on the use of Galerkin's procedure combined with the use of B-splines in order to reduce the system of PDE's to a system of ODE's. The latter system is then solved with a sophisticated ODE software package. Software features include extensive dump/restart facilities, free format input, moderate printed output capability, dynamic storage allocation, and three graphics packages.

Statistical fluctuations of measured signals about their mean are related to physical processes in fuel-failure experiments. Signal variance, correlation, and spectral density are shown to be sensitive measures to instrument response characteristics, of flow-blockage formation, and of boiling phenomena. This sensitivity is demonstrated by a series of examples that use test data from the E6, E7, and L5 experiments. A mathematical model of the Mark-II loop is developed to predict both the mean and the fluctuation behavior of measured test parameters. The analysis is extended to include signal forecasting by the ARIMA time-series model. Techniques that are used to identify the model and to estimate the model parameters are discussed in detail. It is shown that departure of real-time data from the on-line forecasts is a powerful tool for the rapid detection of off-normal conditions. A description of the experiments and the data-reduction process is given in the Appendices.

Annual report discussing the research, development, and management activities of the programs on high-temperature batteries.

This report has been prepared to present a summary description of the Intense Pulsed Neutron System (IPNS). The principal purpose of the document is to assemble the relevant information in a concise and integrated format so that the scientific community and others interested can obtain an accurate impression of the IPNS facilities and their intended purpose. The background and technology for pulsed neutron sources are summarized.

The second mechanized ultrasonic inspection of evaporation EV-702, part of the EBR-II steam-generator system, was completed in March 1978. The 2 1/2 Cr-1 Mo duplex tubes were inspected from the bore (water) side for flaws and changes in wall thickness and for evaluating the condition of the braze between the tubes. An addition to this second inspection was the use of an ultrasonic probe to search for circumferential flaws. The inspection equipment was thoroughly checked and routinely calibrated, using a reference standard containing electrical-discharge-machined notches. Notches as small as 1.6 mm long by 0.25 mm deep were readily detected.