Geostatistics project of the National Uranium Resource Evaluation program

Additional work has been done to display radiometric data from the Lubbock quadrangle in pseudocolor maps. A digitized topographic map of the quadrangle was obtained from the U.S. Geological Survey and this is being incorporated into the study of the radiometric data. Single-record data from the Lake Mead calibration range and from the Slayton test line have been obtained from GeoMETRICS: Inc. and analysis of this data has begun. Principal component analyses have been used to investigate the relationship of geological formation to the location of points in a (Tl, Bi, K) coordinate system. LASL personnel attended a workshop in Grand Junction, Colorado, where some of the problems of calibrating aerial gamma-ray spectrometers were addressed

Technique for dynamic range reduction for Landsat ratio images

The LANDSAT ratio image, obtained by dividing one MSS band by another on a point-by-point basis, has become an established tool for geological applications over the past several years. Display of such images can be difficult since the dynamic range can extend from zero to infinity. A scheme for dynamic range reduction, based on a mathematical model of the multispectral image, is presented. It can be implemented on stand-alone digital image processing systems as well as general purpose computers. This technique also has potential application in machine classification of geological data. Digital image processing examples are presented in which this new scheme is compared with other commonly used techniques for dynamic range reduction

Fan to parallel beam conversion in CAT by rubber sheet transformation

A technique for converting fan-beam projections to parallel-beam projections for use in computed tomography is presented. The problem is approached by use of a rubber sheet transformation. Since the data is discretized, an interpolation step is necessary. For densely sampled data this approach appears satisfactory and a significant reduction in photon noise is observable in computer simulations

Rationale of the ratio image in multispectral remote sensing

A simple mathematical interpretation of the properties of ratio images derived from LANDSAT and other sources of multispectral imagery is presented. A spectral signature is defined which is well represented by ratios of pairs of spectral bands and can be related to the problem of clustering and unsupervised learning. Some practical problems arising in the generation of LANDSAT ratio images are considered, and an effective, simple method for reduction of the dynamic range of such images is presented along with digital image processing examples. 6 figures

Tomographic visualization of stress corrosion cracks in tubing

A feasibility study was conducted to determine the possibility of detecting and sizing cracks in reactor cooling water tubes using tomographic techniques. Due to time and financial constraints, only one tomographic reconstruction using the best technique available was made. The results indicate that tomographic reconstructions can, in fact, detect cracks in the tubing and might possibly be capable of measuring the depth of the cracks. Limits of detectability and sensitivity have not been determined but should be investigated in any future work

Applications of industrial computed tomography at Los Alamos Scientific Laboratory

A research and development program was begun three years ago at the Los Alamos Scientific Laboratory (LASL) to study nonmedical applications of computed tomography. This program had several goals. The first goal was to develop the necessary reconstruction algorithms to accurately reconstruct cross sections of nonmedical industrial objects. The second goal was to be able to perform extensive tomographic simulations to determine the efficacy of tomographic reconstruction with a variety of hardware configurations. The final goal was to construct an inexpensive industrial prototype scanner with a high degree of design flexibility. The implementation of these program goals is described

Industrial applications of computed tomography at Los Alamos Scientific Laboratory

A research and development program was begun two years ago at the Los Alamos Scientific Laboratory (LASL) to study nonmedical applications of computed tomography. This program had several goals. The first goal was to develop the necessary reconstruction algorithms to accurately reconstruct cross sections of nonmedical industrial objects. The second goal was to be able to perform extensive tomographic simulations to determine the efficacy of tomographic reconstruction with a variety of hardware configurations. The final goal was to construct an inexpensive industrial prototype scanner with a high degree of design flexibility. The implementation of these program goals is described

Geostatistics project of the national uranium resource evaluation program. Progress report, April 1981-September 1981

During the period covered by this report, we proposed a method of comparing aerial and ground data as a means of assessing the quality of aerial data. We also compared two methods of partitioning count rates among several isotopes. Time-series analysis and analysis of variance were considered as tools for using aerial radiometric data to aid in designing ground-based sampling experiments. Several methods of computing covariance matrices were compared for use with very large data sets. A study showed a potential for using aerial radiometric data to rank quadrangles according to the Department of Energy's estimated uranium inventories. A discriminant analysis code was transferred to Grand Junction, and several statistics short courses were presented there. Recommended cluster analysis procedures were developed and applied to aerial radiometric data. Reports and papers were prepared on topics such as outlier detection, percentile estimation, discriminant analysis, and statistical package comparison