Radially-Distorted Conjugate Translations

This paper introduces the first minimal solvers that jointly solve for affine-rectification and radial lens distortion from coplanar repeated patterns. Even with imagery from moderately distorted lenses, plane rectification using the pinhole camera model is inaccurate or invalid. The proposed solvers incorporate lens distortion into the camera model and extend accurate rectification to wide-angle imagery, which is now common from consumer cameras. The solvers are derived from constraints induced by the conjugate translations of an imaged scene plane, which are integrated with the division model for radial lens distortion. The hidden-variable trick with ideal saturation is used to reformulate the constraints so that the solvers generated by the Grobner-basis method are stable, small and fast. Rectification and lens distortion are recovered from either one conjugately translated affine-covariant feature or two independently translated similarity-covariant features. The proposed solvers are used in a \RANSAC-based estimator, which gives accurate rectifications after few iterations. The proposed solvers are evaluated against the state-of-the-art and demonstrate significantly better rectifications on noisy measurements. Qualitative results on diverse imagery demonstrate high-accuracy undistortions and rectifications. The source code is publicly available at https://github.com/prittjam/repeats

Experimental Study Of Cmos Structures: Design For Reliability In Hostile Environments

Complementary Metal Oxide Silicon (CMOS) technology has been the fastest growing fabrication process for the Very Large Scale Integrated (VLSI) circuits in the last few years, and long term predictions confirm its future importance. The minimum CMOS feature size is presently about one micron and it is certain that feature dimensions will reach the submicron range in mid nineties.;Smaller dimensions yield advantages, namely greater speed, higher device complexity and performance, and disadvantages such as greater susceptibility to electrical damage. During the past few years, the reliability of CMOS integrated circuits has received much attention, matched by publications on the subject. Higher reliability hardened integrated circuits have been developed as a response to demands for simplified shielding and demands for more reliable systems operating in hostile environments. The key step in developing hardened integrated circuits is the study of the mechanisms that make them fail. By understanding the failure conditions one can design more reliable components, select more suitable materials, and improve in-process control and screening. Also, it allows to develop test patterns, or accelerated test strategies for the evaluation of the integrated circuits susceptibility to damage.;In this study, a series of measurements were performed on a variety of custom fabricated CMOS Charge-Coupled Devices (CCDs) and dedicated modular test structures to investigate the latent model of failure due to Electrostatic Discharge (ESD). Test devices were stressed using the current injection method and measurements of the quiescent current were used to detect the failure thresholds. The fault sites were further isolated and the failure mechanisms studied by measuring the electrical characteristics before and after thermal and optical interaction. The measurements of oxide trapped charge was performed using the capacitance-voltage profiles. A model was proposed to explain the observed phenomena, based on charge injection and trapping in the gate oxide. The experimental methods developed for locating, measuring and analysis of the failure sites have been found sufficiently robust to be generally useful

General specifications for the development of a USL/DBMS NASA/PC R and D distributed workstation

The general specifications for the development of a PC-based distributed workstation (PCDWS) for an information storage and retrieval systems environment are defined. This research proposes the development of a PCDWS prototype as part of the University of Southwestern Louisiana Data Base Management System (USL/DBMS) NASA/PC R and D project in the PC-based workstation environment