New pulsing technique may improve radar ranging systems

Mode of operation for radar ranging system based on ringing frequencies is described. Methods for measuring range and range rate are discussed. Mathematical model is included to describe ringing frequency. Application to acoustic sounding devices is proposed

Mission load dynamic tests of two undensified Space shuttle thermal protection system tiles

Two tests of undensified Space Shuttle thermal protection tiles under combined static and dynamic loads were conducted. The tiles had a density of approximately 144 Kg/cum (LI900 tiles) and were mounted on a strain isolation pad which was 0.41 cm (.160 inch) thick. A combined static and dynamic mission stress histogram representative of the W-3 area of the wing of the orbiter vehicle was applied. The stress histogram was provided by the space shuttle project. Results presented include: tabulation of measured peak and root-mean-square (RMS) accelerations in both compression and tension; peak SIP stress in compression and tension, peak and RMS amplitude response ratios; lateral to vertical response ratios; response time histories; peak stress distributions (histograms), and SIP extension measured both with and without static tension at various mission times

Notes on a Case of Quadruplets.

n/

A Statistical Analysis of Sunflower Growth

This study considers whether the date at which a maternal sunflower begins to flower has a significant impact on the sunflowers grown from its seeds. The data were collected by Professor Jenny Dechaine of the Department of Biology. She ran an experiment which began with one population of sunflowers. From there, seeds were taken from those flowers in the order in which they flowered. Seeds taken from the sunflowers that flowered first became seed group A. Seeds from the next flowering group became seed group B, and so on until seed group H. The purpose of the experiment was to test if there was any relationship between when a seed\u27s maternal plant flowered and a variety of measurements. Data on over 100 sunflowers were collected, recording such information as the number of leaves a plant had, the lengths of the leaves, and whether or not there was a presence of downy mildew. I performed the analysis of the dataset to find any significant differences in the groups of sunflowers. I provide descriptive statistics of each variable, as well as some combinations of seed groups, to better test if there was a significant difference between seeds with maternal plants that flowered early and those with maternal plants that flowered later