AbstractWe describe new applications of the level set approach for following the evolution of complex interfaces. This approach is based on solving an initial value partial differential equation for a propagating level set function, using techniques borrowed from hyperbolic conservation laws. Topological changes, corner and cusp development, and accurate determination of geometric properties such as curvature and normal direction are naturally obtained in this setting. In this paper, we review some recent work, including fast level set methods, extensions to multiple fluid interfaces, generation of complex interior and exterior body-fitted grids, and applications to problems in shape and character recognition.
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AbstractWe describe new applications of the level set approach for following the evolution of complex interfaces. This approach is based on solving an initial value partial differential equation for a propagating level set function, using techniques borrowed from hyperbolic conservation laws. Topological changes, corner and cusp development, and accurate determination of geometric properties such as curvature and normal direction are naturally obtained in this setting. In this paper, we review some recent work, including fast level set methods, extensions to multiple fluid interfaces, generation of complex interior and exterior body-fitted grids, and applications to problems in combustion and material science.
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AbstractPreviously, Adalsteinsson and Sethian have applied the level set formulation to the problem of surface advancement in two and three-dimensional topography simulation of deposition, etching, and lithography processes in integrated circuit fabrication. The level set formulation is based on solving a Hamilton-Jacobi type equation for a propagating level set function, using techniques borrowed from hyperbolic conservation laws. Topological changes, corner and cusp development, and accurate determination of geometric properties such as curvature and normal direction are naturally obtained in this setting. Part I presented the basic equations and algorithms for two dimensional simulations, including the effects of isotropic and uni-directional deposition and etching, visibility, reflection, and material dependent etch/deposition rates. Part II focused on the extension to three dimensions. This paper completes the series, and add the effects of re-deposition, re-emission, and surface diffusion. This requires the solution of the transport equations for arbitrary geometries, and leads to simulations that contain multiple simultaneous competing effects of visibility, directional and source flux functions, complex sputter yield flux functions, wide ranges of sticking coefficients for the re-emission and re-deposition functions, multi-layered fronts and thin film layers.
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AbstractWe design and implement a general algorithm for following the evolution of multiple interfaces and multiple junctions in two and three space dimensions. The core of the technique rests on a level set algorithm for following an interfaces between two regions. This level set formulation is based on solving a Hamilton-Jacobi type equation for a propagating level set function, using techniques borrowed from hyperbolic conservation laws. Topological changes, corner and cusp development, and accurate determination of geometric properties such as curvature and normal direction are naturally obtained in this setting. In this paper, we extend these techniques to an arbitrary number of interfaces in two and three space dimensions, which may intersect in multiple junctions, such as triple points.
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