Experimental results for imaging the low-scattering tissue phantoms based on the derivative estimation through perturbation Monte-Carlo (pMC) method are presented. It is proven that pMC-based methods give superior reconstructions compared to diffusion-based reconstruction methods. An easy way to estimate the Jacobian using analytical expression obtained from perturbation Monte-Carlo method is employed. Simulation studies on the same objects, considered in the experiment, are performed and corresponding results are found to be in reasonable agreement with the experimental studies. It is shown that inter-parameter cross talk in diffusion based methods lead to false results for the low-scattering tissue, where as the pMC-based method gives accurate results.

Abstmct-High-speed evaluation of a large number of polynomial expressions has potential applications in the modeling and real-time display of objects in computer graphics. Using VLSI techniques, chips called pixel planes have been built by Fuchs and his group to evaluate linear expressions on frame buffers. Extending the linear evaluation to quadratic evaluation, however, has resulted in the loss of regularity of interconnection among the cells. In this paper, we present two types of organizations for frame buffers of m x m pixels: one, a single wavefront complex cell array requiring O(m2n) space and the other a simple cell multiple wavefront array with O ( m 2 ) area and O ( n 2 ) wavefronts. Both these organizations have two main advantages over the earlier proposed method. The cells and the interconnection among them are regular and hence are suitable for efficient VLSI implementation. The organization also permits evaluation of higher order polynomials.

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We describe a real-time system that supports design of optimal flight paths over terrains. These paths either maximize view coverage or minimize vehicle exposure to ground. A volume-rendered display of multi-viewpoint visibility and a haptic interface assists the user in selecting, assessing, and refining the computed flight path. We design a three-dimensional scalar field representing the visibility of a point above the terrain, describe an efficient algorithm to compute the visibility field, and develop visual and haptic schemes to interact with the visibility field. Given the origin and destination, the desired flight path is computed using an efficient simulation of an articulated rope under the influence of the visibility gradient. The simulation framework also accepts user input, via the haptic interface, thereby allowing manual refinement of the flight path.

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