29935552
Optimal design of checksum-based checkers for fault detection in linear analog circuits
Traditionally, built-in self-test (BIST) techniques have assumed access to only the input and output nodes of the circuit under test (CUT). It has been shown earlier, that checksum-based checkers can be designed to perform on-line fault detection in linear analog circuits using access to certain internal nodes of CUT. In this paper, we address the problem of optimizing the checker circuitry to maximize the detectability of faults in CUT. The above optimization problem is solved as a linear programming problem. The resulting checker can be used to perform both BIST of CUT and on-line error detection as well. Faults in the checker hardware are taken into account during the checker optimization process.
40448216
Multiple fault detection using single fault test sets
A simulation study of the 74LS181 4-b ALU (arithmetic logic unit) using 16 complete single stuck-at fault test sets demonstrated significantly higher multiple stuck-at fault coverage than predicted by previous theoretical studies. Analysis of the undetected multiple faults shows the effect of circuit and test set characteristics on fault coverage. A fault masking property, defined as self-masking, is observed for the undetected faults in the simulation study. A heuristic is described for evaluating the multiple fault coverage of single stuck-at fault test sets. A second heuristic generates augmented test sets, providing improved multiple stuck-at fault coverage with a minimal increase in test set development cost. >
27941486
Distributed probabilistic diagnosis of MCMs on large area substrates
This paper addresses the issue of testing MCMs on large-area substrates. The cost of testing each MCM may be as high as 40% of the total manufacturing cost. It is critical that the test process be parallelized in order that multiple MCMs may be tested for the cost of testing one MCM. With this objective in mind, we propose a distributed probabilistic diagnosis algorithm for MCMs on large-area substrates. Our algorithm performs better than the existing diagnosis algorithms and can correctly identify almost all MCMs even when the yield is very low (35%). Further it provides upto an order of magnitude reduction in test application time as opposed to serial MCM probe test.
218895568
How to give a good research talk
Giving a good research talk is not easy. We try to identify some things which we have found helpful, in the hope that they may be useful to you.
247123
Defocus video matting
Video matting is the process of pulling a high-quality alpha matte and foreground from a video sequence. Current techniques require either a known background (e.g., a blue screen) or extensive user interaction (e.g., to specify known foreground and background elements). The matting problem is generally under-constrained, since not enough information has been collected at capture time. We propose a novel, fully autonomous method for pulling a matte using multiple synchronized video streams that share a point of view but differ in their plane of focus. The solution is obtained by directly minimizing the error in filter-based image formation equations, which are over-constrained by our rich data stream. Our system solves the fully dynamic video matting problem without user assistance: both the foreground and background may be high frequency and have dynamic content, the foreground may resemble the background, and the scene is lit by natural (as opposed to polarized or collimated) illumination.
18079654
Nonpolygonal isosurface rendering for large volume datasets
Surface-based rendering techniques, particularly those that extract a polygonal approximation of an isosurface, are widely used in volume visualization. As dataset size increases though, the computational demands of these methods can overwhelm typically available computing resources. Recent work on accelerating such techniques has focused on preprocessing the volume data or postprocessing the extracted polygonization. The algorithm presented, concentrates instead on streamlining the surface extraction process itself so as to accelerate the rendering of large volumes. The technique shortens the conventional isosurface visualization pipeline by eliminating the intermediate polygonization. We compute the contribution of the isosurface within a volume cell to the resulting image directly from a simplified numerical description of the cell/surface intersection. The approach also reduces the work in the remaining stages of the visualization process. By quantizing the volume data, we exploit precomputed and cached data at key processing steps to improve rendering efficiency. The resulting implementation provides comparatively fast renderings with reasonable image quality.<<ETX>>
15620342
Autocalibration for virtual environments tracking hardware
We describe two instances in which precise mechanical calibration of virtual environments equipment has been replaced by automated algorithmic calibration through software that encapsulates the hardware design and uses a goal-based approach to adjust calibration parameters. We describe a back-projection system for adjusting the assumed locations of beacons in a head-mounted display tracking system; the calculated errors in the navigation system are used to compute adjustments to the beacon positions to reduce such errors. In a second application, a piggyback headtracking/hand-tracking system is calibrated by a similar reduction of computed errors.
7017581
Multi-finger cursor techniques
The mouse cursor acts as a digital proxy for a finger on graphical displays. Our hands, however, have ten fingers and many degrees of freedom that we use to interact with the world. We posit that by creating graphical cursors that reflect more of the hand's physical properties, we can allow for richer and more fluid interaction. We demonstrate this idea with three new cursors that are controlled by the user's fingers using a multi-point touchpad. The first two techniques allow for simultaneous control of several properties of graphical objects, while the third technique makes several enhancements to object selection.