The movement of fluids in a fractured, porous medium has been the subject of considerable study. This paper presents a continuum model that may be used to evaluate the isothermal movement of water in an unsaturated, fractured, porous medium under slowly changing conditions. This continuum model was developed for use in evaluating the unsaturated zone at the Yucca Mountain site as a potential repository for high‐level nuclear waste. Thus its development has been influenced by the conditions thought to be present at Yucca Mountain. A macroscopic approach and a microscopic approach are used to develop a continuum model to evaluate water movement in a fractured rock mass. Both approaches assume that the pressure head in the fractures and the matrix are identical in a plane perpendicular to flow. Both approaches lead to a single‐flow equation for a fractured rock mass. The two approaches are used to calculate unsaturated hydrologic properties, i.e., relative permeability and saturation as a function of pressure head, for several types of tuff underlying Yucca Mountain, using the best available hydrologic data for the matrix and the fractures. Rock mass properties calculated by both approaches are similar.

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This paper presents an implemented algorithm that automatically designs fiztures and assembly pallets to hold three-dimensional parts. The designed fixtures rigidly constrain and locate the part, obey task constraints, are robust to part shape variations, are easy t o load, and are economical to produce. The algorithm is guaranteed t o find the global optimum solution that satisfies these and other pragmatic conditions. we present the results of the algorithm applied to several practical manufacturing problems. FOT these complei problems the algorithm typically returns initial high-quality fizture designs in less than two minutes, and identifies the global optimum design in just ,over an hour.

This paper presents an implemented algorithm that automatically designs fiztures and assembly pallets to hold three-dimensional parts. The designed fixtures rigidly constrain and locate the part, obey task constraints, are robust to part shape variations, are easy t o load, and are economical to produce. The algorithm is guaranteed t o find the global optimum solution that satisfies these and other pragmatic conditions. we present the results of the algorithm applied to several practical manufacturing problems. FOT these complei problems the algorithm typically returns initial high-quality fizture designs in less than two minutes, and identifies the global optimum design in just ,over an hour.

The data were gathered under WBS number 1.2.1.4,4; however, the report was completed under WBS n_ber 1.2.1.4.4.1.