AUTOPLAN: A PC-based automated mission planning tool

A PC-based automated mission and resource planning tool, AUTOPLAN, is described, with application to small-scale planning and scheduling systems in the Space Station program. The input is a proposed mission profile, including mission duration, number of allowable slip periods, and requirement profiles for one or more resources as a function of time. A corresponding availability profile is also entered for each resource over the whole time interval under study. AUTOPLAN determines all integrated schedules which do not require more than the available resources

An annotated key to the nymphs of the families and subfamilies of mayflies

journal articleAttempts to provide keys to the families and subfamilies of Ephemeroptera nymphs in general entomology textbooks (i.e. Essig (1942), Chu (1949), and Brues, Melander and Carpenter (1954)) have been far from satisfactory. This difficulty exists largely because of the failure of specialists of the Ephemeroptera to provide keys of world-wide application that are sufficiently illustrated to be of value to non-specialists. In the last few decades, however, there have been many figures published that will aid any person attempting to construct such keys. Excellent figures of a variety of families are found in such works as those of Barnard (1932), Spieth (1933), Needham, Traver and Hsu (1935), Ulmer (1940), Crass (1947), Berner (1950), Tshernova (1952), and Burks (1953)

Topological structure of the space of composition operators on L∞L^\infty of an unbounded, locally finite metric space

We study properties of the topological space of composition operators on the Banach algebra of bounded functions on an unbounded, locally finite metric space in the operator norm topology and essential norm topology. Moreover, we characterize the compactness of differences of two such composition operators.Comment: in submissio

An Investigation of Combined Thermal Weakening and Mechanical Disintegration of Hard Rock

The research under modified Contract No. H0220068 has been devoted to experimental thermal-mechanical fragmentation of Missouri red granite in place, and to supporting theoretical analyses. The results of the previous year\u27s experimental work showed that thermal stresses are several times more effective in fragmenting hard rock when they are created within the rock rather than upon the surface. Also, large blocks {4-foot cubes) are not adequate to simulate the response of in situ rock. Based upon laboratory tests an experimental round was designed analogous to an explosive blasting round with coiled wire heating elements placed in drill holes. Three displacement relief faces were required for effective fracture at a 5 kw power level for a 10 inch burden. However, the heaters clogged and failed, and although the rock was effectively fractured, the fragments required considerable mechanical effort to remove them. Electric arcs at 12 kw, utilizing carbon electrodes were employed to create thermal inclusions, and in holes 14 inches in depth with equal burden. The rock was fractured and easily removed, as was also the case with 20 inches depth and overburden. Experiments are in progress to optimize round geometry and energy levels. Major problems are the brittleness of the carbon electrodes and maintaining of a stable arc as the heating is begun. Both of these problems are being solved. Theoretical analyses of temperature and thermal stress distribution are progressing well and procedures are being refined for use of more accurate boundary conditions, temperature-dependent rock properties, and other input parameters. Laboratory experiments are being conducted to determine stress and temperature distribution for a cylindrical geometry for basalt. Calculations of projected rates of advance and excavation costs indicate that for a slot type round the process is technically and economically feasible. --Summary, page 1a